Efimia Souliou

Molecular Epidemiology of Carbapenem-Resistant Acinetobacter baumannii in a Newly Established Greek Hospital

One hundred and sixty-four Acinetobacter baumannii isolates, collected from patients hospitalized in a newly established hospital in Northern Greece during the 8-year period (2001-2008) of its operation, were tested for the presence of Ambler class A and D carbapenemases and typed by random amplified polymorphic DNA and pulsed-field gel electrophoresis. Isolates were clustered into five distinct clones. The majority of isolates were carrying the bla(OXA-58) gene, while a new clone emerged in 2008.

Correlation of the extent and duration of rhegmatogenous retinal detachment with the expression of matrix metalloproteinases in the vitreous.

Background: Investigation of the activity of matrix metalloproteinase (MMP)-2 and -9 and protein levels of MMP-1, -3, -8, and the tissue inhibitor of MMPs (TIMP)-1 in the vitreous of patients with rhegmatogenous retinal detachment (RRD) and establishment of potential correlations of MMPs with clinical parameters. Methods: Thirty-two vitreous samples from patients with RRD and 9 vitreous samples from human organ donors (controls) were assayed for MMP-1,-3, -8, and TIMP-1 levels using enzyme-linked immunosorbent assay and MMP-2 and -9 activity employing gelatin zymography. Results: MMP-1, MMP-3, proMMP-2, proMMP-9, MMP-9, and TIMP-1 were higher in vitreous from patients with RRD as compared to organ donors. Overall, MMPs and TIMPs were differentially expressed in vitreous from RRD with respect to the duration and extent of RRD. Regression analysis for all data indicated that a model consisting of MMP-2 and TIMP-1 could estimate the extent of RRD. Conclusion: Levels of MMPs and TIMP-1 studied are elevated in vitreous during RRD. MMP-2 and TIMP-1 may have a more prominent and persistent role than other MMPs in the wound healing process of the retina during RRD. A regression model consisting of MMP-2 and TIMP-1 may prove to be of potential use in providing information for the evaluation of the extent of RRD.

Expression of matrix metalloproteinases in the subretinal fluid correlates with the extent of rhegmatogenous retinal detachment

BackgroundWe investigated the activity of matrix metalloproteinase (MMP)−2 and −9 and the protein levels of MMP−1, −3, −8 and the tissue inhibitor of MMPs (TIMP)−1 in the subretinal fluid (SRF) of patients with rhegmatogenous retinal detachment (RRD) and establishment of potential correlations with clinical parameters.MethodsThirty-seven SRF from RRD patients and nine vitreous samples from the human eye of organ donors (controls) were collected and assayed for MMP−1,−3,−8 and TIMP−1 levels using ELISA and for MMP−2 and −9 activity employing gelatin zymography.ResultsMMP−1, MMP−3, MMP−8, proMMP−2, proMMP−9, MMP−9 and TIMP−1 levels were higher in SRF compared with vitreous fluid. Overall, MMPs and TIMPs were differentially expressed in SRF with respect to duration and extent of RRD, as well as to stage of proliferative vitreoretinopathy. Regression analysis for all data indicated that a model consisting of MMP−3, MMP−8 and proMMP−9 could estimate the extent of RRD.ConclusionsMMPs and TIMP−1 levels are elevated in SRF during RRD. A regression model consisting of MMP−3, MMP−8 and proMMP−9 may be proved to be of potential use in providing information for evaluation of the extent of RRD.

Correlation of matrix metalloproteinase levels with the grade of proliferative vitreoretinopathy in the subretinal fluid and vitreous during rhegmatogenous retinal detachment

Purpose:  We investigated the activity of matrix metalloproteinase (MMP)‐2 and ‐9 and their latent pro‐forms (proMMP‐2, ‐9), and protein levels of MMP‐1, ‐3, ‐8 and tissue inhibitor of MMPs (TIMP)‐1 in the subretinal fluid (SRF) and vitreous of patients with rhegmatogenous retinal detachment (RRD). Potential correlations with proliferative vitreoretinopathy (PVR) grade were determined.

Laboratory diagnosis of Mycoplasma pneumoniae respiratory tract infections in children

Mycoplasma pneumoniae is a common respiratory tractpathogen that causes up to 40% of cases of community-acquired pneumonia in children [1]. A specific diagnosis isessential because treatment of M. pneumoniae infection withβ-lactam antibiotics is ineffective. In routine laboratories,serology remains an important diagnostic tool [2, 3].However, it can only provide a retrospective diagnosis andpaired samples are required. Recently developed PCRtechniques show high levels of specificity and sensitivity forthe rapid detection of M. pneumoniae in clinical specimens[4, 5]; however, PCR alone is not always sufficient for adiagnosis [3]. In lieu of a gold-standard diagnostic method,we aimed to evaluate the laboratory methods currently usedto diagnose M. pneumoniae infection in order to find the onemost suitable for rapidly diagnosing the illness, especially inthe early phase of disease.During a 15-month period, a throat swab (viscose swab)andfirstserumspecimenweretakenonadmissionfromatotalof 75 children (42 males, 33 females; mean age 6.2 years;range 4 months–14 years) who were hospitalized fortreatment of a respiratory tract infection (RTI). According tothe guidelines of the British Thoracic Society, 53 of thesechildren had pneumonia, 16 pharyngitis and 6 tracheobron-chitis. A second serum specimen was obtained 9–24 dayslater.ThethroatspecimenswereexaminedforthepresenceofM. pneumoniae using culture in methylene blue–glucosediphasic medium (Oxoid, Basingstoke, UK), a sandwichenzyme-immunoassay for antigen detection (EIA-Ag Virion/Serion, Germany) and a PCR technique for DNA detection(extracted DNA was amplified by the primer pair P1-1 andP1-3 for the P1 adhesin gene [6]). Antibodies against M.pneumoniae were measured using the immunofluorescenceassay (IFA) for IgG and IgM (Vircell, Granada, Spain),enzyme-linked immunosorbent assay (ELISA) for IgG(Platelia BioRad, Marnes-la-Coquette, France) and IgA(Virotech, Russelsheim, Germany), and capture-ELISA forIgM (Platelia BioRad). Toconfirm thespecificityofIgMandIgAantibodydetection,theWesternblottechnique(Virotech)wasadditionallyperformed.Thismethodiscurrentlythemostspecific for detecting anti-M. pneumoniae antibodies [3]. ForIgM, a positive result requires ≥9 bands including P1protein; for IgA, >24 bands are required including P1protein. In the present study a current or recent infectionwas considered to have occurred definitely if at least two ofthe following criteria were met: (1) positive PCR and/orculture, (2) positive IgM antibodies (in the first and/or thesecond sample), (3) seroconversion or significant increase ofIgG antibodies (fourfold increase for IFA, twofold increasefor ELISA), or high IgG titers >40 AU/ml for ELISA.M. pneumoniae was detected by PCR in the throat-swabspecimens of 11 of 75 patients, by culture in three and bythe antigen detection test in only one. All culture-positivesamples were also positive by PCR. The complete resultsobtained using the various methods for the samples of eachof the 75 children studied are shown in Table 1.According to the diagnostic criteria, a definite diagnosisof current or recent M. pneumoniae infection was obtainedfor a total of 12 of the 75 pediatric patients (Table 1; patients1–12; ten with pneumonia and two with pharyngitis). Four

First detection of Rickettsia slovaca in Greece

Seven hundred and three ticks collected in November and June of 2004–2006 from domestic animals in four localities of Halkidiki prefecture, Northern Greece, were tested for the presence of ricketsial DNA. Rickettsia slovaca was detected in one pool of Rhipicephalus bursa ticks, representing the first report of detection of R. slovaca in Greece.

Serological survey of immunity to tetanus in adult population of Northern Halkidiki, Greece.

Background: Despite the implementation of the obligatory anti-tetanus vaccination, the tetanus cases in Greece are not eliminated. Because of the increased possibility of Clostridium tetani infection of the Northern Halkidiki population – like any other rural population – the evaluation of the immunity to tetanus in the area is considered necessary. Methods: The tetanus antitoxin levels were determined using the enzyme-linked immunosorbent assay (ELISA) in 405 healthy adult individuals attending the health center for routine laboratory tests. Results: 64.4% of the studied population was found protected (tetanus antitoxin levels ≥ 0.1 IU/ml). The percentage of protected people decreased as age increased from 83.3% in the 21–30 to 51.2% in the > 60 age group. 82.1% of the tested males and 52.6% of the tested females had tetanus antitoxin levels ≥ 0.1 IU/ml (p < 0.0001). The percentages of immune men (100–66.2% in various age groups) were found higher than those of women (80.8–35.5% in the respective age groups). The geometrical mean titres (GMTs) were 0.44 in all of 261 immune people, 0.53 in 133 immune men and 0.37 in 128 immune women (p = 0.0021). Conclusion: The proportion of protection among men over 60 and women over 30 years old is inadequate, the levels of tetanus antitoxin decline with age and a significant difference was found between the proportion of protection of males and females.

Chemokine CXCL-1 Expression in the Subretinal Fluid during Rhegmatogenous Retinal Detachment

Abstract Purpose: To investigate the expression of chemokine CXCL-1 in the subretinal fluid (SRF) during rhegmatogenous retinal detachment (RRD) and identify potential correlations with number of quadrants involved and duration of the detachment. Methods and Results: Inclusion criteria were patients aged 18 years or older and primary RRD possibly complicated by proliferative vitreoretinopathy (PVR). CXCL-1 levels were measured in 36 SRF samples from 36 RRD patients. Mean CXCL-1 levels (102 ± 37 pg/mL) were significantly higher (p = 0.050) compared to controls. CXCL-1 levels correlated significantly with age (p = 0.001) and RRD duration (p = 0.002). Maximum CXCL-1 levels coincided with total RRD, 29- to 60-day duration and PVR grade C. Conclusions: The findings of this study may contribute to increased understanding regarding the role of CXCL-1 during the onset and progression of the wound healing process in the context of RRD and PVR.

Chemokine CXCL-1: activity in the vitreous during proliferative vitreoretinopathy

The aim of this study was to investigate CXCL‐1 chemokine levels in the vitreous during rhegmatogenous retinal detachment (RRD) with and without proliferative vitreoretinopathy (PVR) and identify possible correlations with clinical parameters (extent and duration or RRD and PVR grade). Vitreous samples from patients with primary RRD with or without PVR were collected and assayed using a double antibody enzyme‐linked immunosorbent assay (ELISA). Eleven vitreous samples from organ donors were employed as a control group. CXCL‐1 levels were measured in 35 vitreous samples from 35 RRD patients. Mean CXCL‐1 levels (64·82 ± 6·47 pg/ml) were significantly higher (P = 0·048) compared to controls. There was a significant positive correlation between CXCL‐1 levels and the extent of the detachment (r = 0·794, P = 0·006). Peak CXCL‐1 levels coincided with 3+ quadrant RRD, an interim of 29–60 days’ duration and PVR grade B. Increased CXCL‐1 levels may be indicative of mild inflammation in the detached retina and the adjacent vitreous. The results of the present study may provide novel insight into the complex interactions taking place during the early and late stages of RRD complicated by PVR.