12th Congress of the European Hematology ... - Haematologica

12 th Congress of the European Hematology Association
fold higher mean levels of aCaspase-3 (107 U/mL) in comparison to all
AMLs, while the levels of bcl-2 (744 U/mL) and ÒPARP (10.17 U/mL)
were relatively low: a profile similar to observed in RAEB. Interestingly,
the molecular analysis showed MLF1 mRNA expression in these cases.
This finding might provide some evidence that at least some of AMLs
result from the leukaemic transformation of a preceding undiagnosed
MDS. Conclusions. By dividing MDS according to IPSS, definite patterns
of key apoptosis related proteins can be identified. Intermediate and
high risk MDS groups are associated with the parallel activation of apoptotic
and anti-apoptotic mechanisms. The dysregulation of normal balance
of cell death and survival might be one of the mechanisms of disease
progression. Besides, although AML development is accompanied
by a fall in pro-apoptotic versus anti-apoptotic parameters, the heterogeneity
in the examined protein patterns indicates that additional factors
might play a role in leukaemic pathogenesis and warrants further
prospective studies. Acknowledgements: Study funded by the National
Fund, Bulgarian Ministry of Education and Science.
1268
ENGRAFTMENT OF FLUORESCENTLY-LABELED BONE MARROW STROMAL CELLS INTO
THE CEREBRAL CORTEX INJURY SITE IN THE RAT
M. Opydo-Chanek, Z. Dabrowski
Jagiellonian University, CRACOW, Poland
Backround. In recent years there has been an increasing interest in bone
marrow stromal cells (BMSCs, also termed mesenchymal stem cells)
due to their potential therapeutic function, also connected with the
repair of central nervous system injury. Initial preclinical studies demonstrated
the ability of BMSCs to migrate, engraft into the damaged tissue
and differentiate into residential-like cells. Aims. The present study
was undertaken to demonstrate the engraftment capacity and survival
of BMSCs administrated intralesionaly after cerebral cortex injury. Methods.
The experiment was carried out on female Wistar rats (all experimental
procedures have been approved by the Local Bioethical Committee).
Mechanical injury was induced with a drill in the left cerebral cortex.
BMSCs (2×106 /10 µL PBS)were administrated directly to the lesion
site immediately after injury. Control group received the same volume
of PBS. BMSCs were isolated from allogeneic bone marrow aspirate
obtained from rat femurs and cultured for 14 days in Dulbecco’s Modified
Eagle Medium (DMEM) containing 10% fetal calf serum and
120U/mL penicillin. 24 h prior to transplantation bis-benzimide (Hoechst
33342) was added to the medium in order to fluorescently label the
BMSCs nuclei. Brain tissue was processed for preparation of sections,
which were used for observation in fluorescence microscope. Cultured
cells were observed under fluorescence and light microscope with
Nomarsky contrast. Results. After 14 days of culture the cells approached
confluency and at least three morphologically different types of cells
could be seen: spindle-shaped cells, large flat cells and small round cells.
Bis-benzimide labeled nuclei of almost all BMSCs. After intralesional
administration large number of BMSCs was observed in the lumen of
injury and also in the surrounding parenchyma 2 days post injury and
were still visible after 30 days. Some BMSCs were found in contact with
vessel walls. Engrafted cells were preferentially localized to the glial scar
on day 30. BMSCs were not seen in the contrlateral hemisphere. Conclusion.
Transplanted BMSCs engraft in the parenchyma of the injured
brain and survive in the microenvironment of the injured tissue at least
30 days after intralesional administration. Long-term survival of these
cells in the area of injury and their presence in the site of glial scar suggest
that BMSCs are actively involved in the healing processes of the
damaged brain.
This work was supported by the grant no. BW/IZ/11/2005
1269
RISK FACTORS FOR BACTERAEMIA CAUSED BY EXTENDED-SPECTRUM
β-LACTAMASE PRODUCING-ESCHERICHIA COLI IN HOSPITALIZED
HAEMATOLOGICAL PATIENTS
E. Gil Espárraga, C. Martín Aguilera, P. Cerezuela Martinez,
F. De la Cruz Vicente, M. Aguilar, M. Ruiz, M. Herreros, I. Espigado,
J.M. Cisneros
HHUU Virgen del Rocio, SEVILLE, Spain
Introduction. Bacteraemia caused by extended-spectrum β-lactamase
(ESBL) producing-E. coli has growing incidence and limited therapeutic
options. The study of the risk factors for its development has not been
patient-population stratified. The aim of this study is to describe the risk
factors for the onset of bacteraemia by ESBL producing-E. coli (ESBL-
460 | haematologica/the hematology journal | 2007; 92(s1)
EC) in the adult hospitalized haematological setting. Material and methods.
Design: prospective study of cases and controls with two control
groups between February 2005 to May 2006. Case definition: haematological
inpatient with ESBL-EC bacteraemia. Control definition: group A:
haematological inpatient with bacteraemia by E. coli not producting ESBL
(1:3); group B: haematological inpatient without bacteraemia immediately
hospitalized after one case (1:4). The following variables were analyzed:
age, sex, type (urgent/programmed) of hospitalization, haematological
disease, chemotherapy, central venous catheter, antibacterial prophylaxis,
GCS-F administration, antibiotic treatment and neutropenia.
Clonal relationship of the isolates was done using REP-PCR. Univariate
and multivariate analysis of the risk factors were performed. Results. One
hundred and twelve episodes of bacteraemia occurred: isolates were E.
coli in 29 (26%) cases and ESBL-EC in 9 (31%) cases. There were not difference
in the basal characteristics of cases (n=9) and controls of the
groups A (n=20) and B (n=36), regarding to age, sex, and type hospitalization.
ESBL-EC strains were polyclonal. The univariate analysis showed
the following variables to be more frequent in the cases than in the group
A of controls: diagnosis of acute leukemia (89% vs. 50%, p