Review Article -The role of Toll-like receptors in innate immunity

M. Mavrouli, V. Kapsimali, A. Tsakris
Department of Microbiology, Medical School, University of Athens, Athens, Greece


The innate immune system constitutes the first line of defence against invading microbes, which
is based on the pattern recognition receptors (PRRs) that recognize molecular patterns associated
with pathogens (PAMPs). Toll-like receptors (TLRs), the most distinguished of PRRs, detect potential
pathogens and activate intracellular signaling pathways that culminate in the production of proinflammatory
mediators. In order to escape from the host inflammatory response, microbes have
evolved multiple evasion and subversion strategies. Besides exogenous PAMPs, TLRs can bind with
molecular patterns produced by tissue damage or cell apoptosis (DAMPs). Under certain circumstances,
this interaction drives to aberrant activation and unrestricted inflammatory responses,
contributing to the development of autoimmune diseases. Rare inherited defects of TLR and NF-
κB dependent responses and single nucleotide polymorphisms (SNPs) within TLR genes act upon
the capacity of the host to mount a proper immune response and are characterized by an increased
or altered susceptibility to infectious, inflammatory and allergic diseases. Novel immunotherapeutic
approaches are developed based on both activation and inhibition of TLR triggering, and TLR
agonists and antagonists have a strong potential for prevention and intervention in infectious diseases.
The challenge is to find a balance between the suppression of disease and the retention of
the beneficial host immune response.
Key words:Toll-like receptors, innate immunity

Utilization management in clinical laboratories

S. Diamantatou,1,3 G. Vrioni,2 C. Stoforos,1 A. Tsakris,2 T. Palaskas1
1Department of Economic and Regional Development, Panteion University of Social and Political Sciences,
Athens, Greece
2 Department of Microbiology, Medical School, National and Kapodistrian University of Athens, Athens,
3 University General Hospital “Attikon”, Athens, Greece

The changing environment of healthcare sector imposes, among others, the reexamination of its
management. In greek hospitals the need to improve their performance, in terms of efficiency and
effectiveness, is of paramount importance. To this extend, the paper takes the discussion from the
issue of crisis management to strategic management emphasizing the utilization management.
The crucial role of clinical laboratories will be strengthening further by adopting utilization management,
enabling them to improve their performance and the quality of their services to patients
and other users. The aim of the paper is, through an extensive review of the most recent relevant
literature, to provide -to the under reform Greek healthcare system- a new management approach
for clinical laboratories. The new approach of health management, adds value to both patients
and to units applied, leading to more efficient and effective performance conforming to the new
public management.

Key words:utilization management, clinical laboratories, efficiency, effectiveness, performance,
healthcare management

Original Article - Comparative epidemiological study of Pseudomonas aeruginosa isolates during two time periods in a tertiary care hospital

M. Koutsogiannou,1 E. Drougka,1 A. Liakopoulos,2 E. Jelastopulu,3 E. Petinaki,2 E. D. Anastassiou,1
I. Spiliopoulou,1 M. Christofidou1
1Department of Microbiology, School of Medicine, University of Patras, Patras, Greece
2Department of Microbiology, School of Medicine, University of Thessalia, Larissa, Greece
3Department of Public Health, School of Medicine, University of Patras, Patras, Greece

Pseudomonas aeruginosa is a nosocomial pathogen of clinical importance carrying virulence and
antibiotic resistance determinants. In the present study, phenotypic and genotypic characteristics
of P. aeruginosa isolates collected at the University General Hospital of Patras (UGHP) in two time
periods were investigated. Two groups of P. aeruginosa clinical isolates were compared collected with
one year interval, in theUGHP. Group A consisted of 120 isolates recovered during one year (2004),
whereas, group B included240 recovered during a two year period (2006-2007). P. aeruginosa isolates
were identified at the species level by standard methods (Oxiferm, BD, BBL). Antibiotic susceptibility
testing was performed for the group A by the Etest for piperacillin, aztreonam, imipenem, tobramycin and
ciprofloxacin, whereas, in group B by the agar disk diffusion method for piperacillin, carbenicillin,
azlocillin, ticarcillin-clavulanic acid, ceftazidime, aztreonam, imipenemamikacin, tobramycin,
netilmicin and ciprofloxacin, while MIC determination of colistin by the Etest (bioMerieux, Marcy
l’ Etoile, France), (CLSI 2008). The production of metallo-beta-lactamases (MBL) was investigated
by the double strip Etest-MBL (bioMerieux). Serotyping was performed by 16 monovalent antisera.
In group B, blaVIM, exoY, exoT, exoS and exoU genes were investigated by PCR and blaVIM genes were
identified by sequencing analysis. PFGE (SpeI) was performed in all isolates of bothgroups. The
main PFGE types of group B were characterized by MLST. Phenotypic and genotypic characteristics
of P. aeruginosa were compared between groups. According to our results, phenotypic and genotypic
analysis of isolates demonstrated the prevalence of multidrug-resistant P. aeruginosa (MDRPA)
mainly serotype O11 clones, especially in the Internal Medicine during 2004 (group A) and in the
ICU during 2006 and 2007 (group B). Fifty nine patients from group A (59/120), mainly hospitalized
in the Internal Medicine, and 152 from group B (152/240), mainly in the ICU, were colonized or infected
with MDRPA. High rate of MBL-positive isolates was observed in group A compared to group
B (45% vs 33%), mainly in the Internal Medicine. All MBL-positive isolates of group B carried blaVIM-
2 and blaVIM-1 genes. Among isolates of group B, exoU gene was detected mainly in isolates from
the ICU, whereas, exoS in isolates from other wards. In group A strains, four dominant PFGE types
were characterized: A, B, C and D. In group B five PFGE types, a, d, b, c and s, different from the
aforementioned pulsotypes, which were associated with ST235, ST111, ST253, ST309 and ST639.
Significant polyclonality was observed in group A as compared to group B.
In conclusion, this study describes two independent clonal outbreaks of MDRPA in the UGHP which
occurred primarily in the Internal Medicine Ward (group A) and after one year interval in the ICU
(group B).

Key words: P. aeruginosa, epidemiological study, clones, MLST, toxins

The contribution of the Chair of Microbiology of Athens Medical School in Greek School Hygiene (1900-1920)

C. Tsiamis, G. Vrioni, V. Kapsimali, G. Arsenis, A. Tsakris
Department of Microbiology, Medical School, National and Kapodistrian University of Athens,Greece

The aim of the study is the contribution of the Chair of Microbiology of Athens University Medical
School, in the organization and development of school health services during the period 1900-
1920. In the early 20th century child morbidity and mortality in Greece were extremely high. The
tragic hygienic conditions of the Greek primary and secondary schools, led Professor of Microbiology
Constantinos Savvas and his colleague, Emmanuel Lambadarios, to introduce the principles
of the School Hygiene in Greece. The School Health Service of the Ministry of Public Education established
the rules of schools’ construction and fought against infectious diseases such as smallpox,
measles, scarlet fever, diphtheritis, meningitis, etc. The contribution of Greek Microbiology in School
Hygiene is considered important and successful, based on the gradual reduction of child mortality
until the early 1920.

Key words: Greece, History of Microbiology, Public
Health, School Hygiene

ΕΝΔΙΑΦΕΡΟΥΣΑ ΠΕΡΙΠΤΩΣΗ Περίπτωση ξηράς γάγγραινας δεξιάς άκρας χειρός από Vibrio vulnificus μετά από δήγμα καβουριού

Α. Γερογιώκας1, Ο. Ζαρκωτού1, Κ. Αυγουλέα1, Β. Μάμαλη1, Π. Τσελιώτη2, Α. Πρεκατές2, Κ. Θέμελη-Διγαλάκη1

1Μικροβιολογικό Εργαστήριο και 2Μονάδα Εντατικής Θεραπείας Γενικό Νοσοκομείο Πειραιά «Τζάνειο»


Περιγράφεται περίπτωση ξηράς γάγγραινας δεξιάς άκρας χειρός από Vibrio vulnificus μετά από δήγμα καβουριού. Το V. vulnificus σχετίζεται με πρωτοπαθή σηψαιμία, μετά από κατανάλωση μολυσμένων θαλασσινών και με νεκρωτικές λοιμώξεις μαλακών μορίων, μετά από έκθεση πληγής σε μολυσμένο νερό. Οι λοιμώξεις είναι συνήθως ευκαιριακές και αφορούν άτομα ανοσοκατεσταλμένα ή με υποκείμενα νοσήματα.