مجال التميز
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تميز دراسي و بحثي
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البحوث المنشورة
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البحث (1):
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عنوان البحث:
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Anti-hepatitis E virus seropositivity
in a group of male blood donors in Makkah, Saudi Arabia
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رابط البحث:
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Link1
Link2
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تاريخ النشر:
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28/02/2013
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موجز عن البحث:
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OBJECTIVES: To determine the seropositivity of
Immunoglobulin-G and Immunoglobulin-M to hepatitis E virus in male blood
donors in Makkah, Saudi Arabia.
METHODS: The study was carried out from March to
August 2009, in which 900 blood samples were collected from 4 different
hospital blood banks in Makkah City: AL-Noor Hospital, Central Blood Bank,
Maternity and Children Hospital, and Herra Hospital. All the samples were
tested for Immunoglobulin-G and Immunoglobulin-M antibodies specific to
hepatitis E virus using the enzyme-linked immunosorbent assay test.
RESULTS: Hepatitis E virus-specific
Immunoglobulin-G antibodies were detected in 168/900 (18.7%), and IgM in
39/900 (4.3%) samples. Prevalence of the former was found to be higher in
non-Saudi donors. In addition, its prevalence increased with age. Moreover,
its prevalence was found to be higher in uneducated donors and in donors who
drank well-water.
CONCLUSION: Exposure to hepatitis E virus among blood
donors in Makkah City was high in comparison to the neighbouring areas in the
region. Further studies are warranted to determine the true seroprevalence of
the virus in the society at large.
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البحث (2):
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عنوان البحث:
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Multiple myeloma: the bone marrow
microenvironment and its relation to treatment
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رابط البحث:
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Link
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تاريخ النشر:
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30/09/2013
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موجز عن البحث:
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Multiple myeloma
is the most common haematological malignancy yet currently it remains
incurable. For decades the mainstay in therapy has been non-targeted
approaches including genotoxic agents and immunosuppressants. With myeloma
predominantly affecting an elderly population, who are vulnerable to
aggressive therapy, these non-specific approaches have resulted in poor
survival. However, in recent years an explosion of collaborative research
into myeloma has identified molecular interactions between myeloma cells and
the bone marrow microenvironment as promoting myeloma development and
associated complications such as bone lesions due to osteolysis. At the same
time, a better understanding of the adhesion molecules, cytokines and
signalling pathways involved in myeloma has led to the development of new
targeted therapies, which are improving the quality of life for patients and
significantly extending median patient survival. This review explores the
current understanding of molecular pathways that promote myeloma progression
and lead to bone destruction, with particular reference to the influence of
interactions with the bone marrow microenvironment. It describes molecular
targets for therapy with reference to the new therapeutics and their improved
efficacy. While the outlook for myeloma patients has improved in recent years
as a result of these new approaches, drug resistance remains a problem and
future therapies will also need to address the molecular mechanisms of
resistance in order to improve further the outcome for patients with this
disease.
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المؤتمرات العلمية:
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المؤتمر (1):
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عنوان المؤتمر:
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Centre
for research in Biosciences annual meeting
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تاريخ الإنعقاد:
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Jan
2014
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مكان
الإنعقاد:
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Bristol,
UK
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طبيعة المشاركة:
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Poster presentation
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عنوان المشاركة:
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Development
of an in vitro 3D bone marrow model
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ملخص المشاركة:
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The
function of the bone marrow is known to be affected by both haemopoietic
malignancies as well as chemotherapy used to treat it. In order to
appropriately evaluate the role of disease versus treatment, this study aims
to develop a novel three-dimensional in vitro culture system of the bone
marrow microenvironment using mesenchymal stem cells (MSCs) and commercially
available novel matrices.
Initially
culture conditions and manipulation of the matrices required optimisation;
MSC growth and proliferation was evaluated in three different culture medium
(low glucose-DMEM, DMEM/f12 and α-MEM), utilising four different
concentrations of foetal bovine serum (0, 5, 11, and 17%), and also comparing
supplementation with L-glutamine or GlutaMax. Two different commercially
available matrices (Nanofiber and BioMerix scaffolds) have been employed in
this study to evaluate the seeding and growth of the MSCs. A limited volume
of cells resuspended in culture medium was required to ensure cells adhered
to the scaffold and not the culture well, the following volumes and adherence
times were evaluated: (5, 10, 15, and 20μl for BioMerix, and 12.5, 25, 50 and
100 μl for Nanofiber for 30, 60, 90 and 120 minutes). In addition, seeding
cells on the top of scaffolds was compared in stable and rotatory movement.
Due to the thickness and the density of the matrices, visualizing MSCs is
difficult and several protocols including (trypan blue and neutral red) have
been developed to ensure clear visualization of the cells. Retrieving MSCs
from these scaffolds is essential to perform further analysis and evaluate
functionality; trypsin and versin were used to maximize the final yield with
minimum cell damage. To assess the cellular shape changes, localization and
the cell-cell interactions, MSCs were stained using Oregon green 488-cell
tracker. This cell tracer enabled the visualisation of cells using the
fluorescent, confocal and 500-LumaScope microscopes. Furthermore, this stains
the live cells and enables tracking of cellular proliferation in the
scaffolds. Cell tracker optimisation was carried out to determine the
appropriate concentration to give a suitable signal for visualizing cells,
even after two weeks of experimentation.
Medium
evaluation showed that MSCs grow better in DMEM/F12 compared to other types
and the growth rate is directly proportion with the serum concentration.
Furthermore, medium supplemented with L-glutamin showed better growth
compared to those in GlutaMax. Additionally, using Biomerix scaffold required
to resuspend of the cell number in 5 μl compared to 25 μl for the Nanofiber
matrices. In addition, MSCs need up to 120 minutes to adhere to the NanoFiber
that is more than the time needed in the BioMerix (90minutes).
In
conclusion, establishing this model can help in the investigation of MSCs
proliferation, differentiation, gene expression, protein level and
expression, and cell behaviour in normal and diseased conditions. In
addition, this model will be evaluated and compared with the traditional 2D
culture technique to assess the suitability of studying MSCs in vitro and
mimicking the in vivo situation by comparison with bone marrow from leukaemia
patients in future studies.
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المؤتمر (2):
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عنوان المؤتمر:
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Centre
for research in Biosciences annual meeting
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تاريخ الإنعقاد:
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16/01/2015
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مكان
الإنعقاد:
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Bristol,
UK
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طبيعة المشاركة:
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Poster
presentation
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عنوان المشاركة:
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Evaluating
the behaviour of stromal cell line (HS-5) in 3D culture
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ملخص المشاركة:
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Immortalized
stromal cells from human marrow (HS-5) were used in this study and their
behaviour was recorded in a novel three-dimensional in vitro culture system
using commercially available novel matrices (Biomerix, Nanofiber and
Alvetex).
Initially,
primary human Bone Marrow Mesenchymal Stem Cells (BM-MSCs) were used to
develop this 3D culture model, however, these cells were difficult in aspects
of cultivation and maintenance when used in this model. This was probably
because of the low proliferation rates and due to the challenge in retrieving
BM-MSC from these scaffolds. Nevertheless, BM-MSCs showed different
morphology when they were seeded in the nanofiber compared to those seeded in
the biomerix scaffolds. In addition, it was difficult to maintain cells
homogeneity and there was variation between each experiment. For these reasons, using the HS-5 BM
stromal cell line was an alternative to establish the model and evaluate cell
functionality differences between the 2D and the 3D cultures. In this study,
cell morphology and proliferation in the 3D scaffolds were evaluated and
compared to determine the difference between the primary BM-MSCs and the cell
line. In addition, HS-5 growth was
compared between the 2D and the 3D cultures over seven days. Also cellular
viability and size were assessed.
The
results indicate that there was no difference between the primary BM-MSC and
the cell line in morphology, they both presented as fibroblastic cell
structure in 2D culture while presenting as rounded cells in the 3D culture.
BM-MSCs were not able to penetrate into the nanofiber matrices, however HS-5
cells were able to grow inside the nanofiber and had similar structure to
those cultivated in the other scaffolds.
In addition, there were statistical differences in cell numbers when
those in the 3D culture were compared to the 2D. Moreover, there were
differences in cell size between the techniques as well as cell
viability. Some of the cells grown
into 3D culture were found floating in the medium during the culture period
and some cells adhered to the well forming a monolayer.
In
conclusion, establishing this model using HS-5 can help in the investigation
of MSCs proliferation, differentiation, gene expression, protein expression,
and cell behaviour in normal and diseased conditions. In addition, this model
will be evaluated and compared with the traditional 2D culture technique to
assess the suitability of studying MSCs in vitro and mimicking the in vivo
situation by comparison with bone marrow from leukaemia patients in future
studies.
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المؤتمر (3):
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عنوان المؤتمر:
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The 2015 Stem Cells: From
Basic Research to Bioprocessing
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تاريخ الإنعقاد:
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09-11/06/2015
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مكان
الإنعقاد:
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London, UK
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طبيعة المشاركة:
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Poster presentation
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عنوان المشاركة:
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Mesenchymal Stem Cells
presented difference in behaviour between 3D scaffolds and in 2D culture
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ملخص المشاركة:
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Developing a novel
three-dimensional (3D) in vitro model of the bone marrow microenvironment
using bone marrow mesenchymal stem cells (BM-MSCs) in commercial matrices
involves a series of distinct processes. This starts with selecting an
appropriate cell source and growth environment. Then choosing the appropriate
scaffold that mimic the in vivo situation of the bone marrow. Primary cells
isolated from healthy donors have low proliferation rate and lack homogeneity
that can result in experimental variation. This study evaluated the
immortalized stromal cell line HS-5 as an alternative cell source and
evaluated their behaviour in the three different 3D cultures (Biomerix,
Nanofiber and Alvetex). Cell morphology and proliferation in the 3D scaffolds
were evaluated and compared to determine the difference between the normal
BM-MSCs and cell line. In addition,
Cell viability and CD markers expression were compared between the 2D and the
3D cultures in seven days. Also cellular size were assessed and 12 reference
genes expression was compared between these cultures.
The results indicate that
there was no difference between the normal and cell line in morphology, they
both presented fibroblastic cell structure in 2D culture while presenting
rounded cells in the 3D culture. BM-MSCs were not able to penetrate into the
nonofiber matrices; however, HS-5 cells were able to grow inside the
nanofiber and has different structure to those cultivated into the other scaffolds.
In addition, there were significant difference in cell number between the 3D
cultures and the 2D. Moreover, there were differences in cell size between
the techniques as well as cell viability. Some of the cells grown into 3D
culture was found floating in the medium during the culture period and some
cells adhered to the well forming a monolayer. In addition, the expression
level of the 12 reference genes was different between the 2D and the 3D
culture, but also they have different expression level between the 3D
cultures.
In conclusion, BM-MSCs
behaviour is different in 2D compared to 3D cultures. Also the difference
between 3D scaffolds lead to variation in cellular behaviour.
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المؤتمر (4):
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عنوان المؤتمر:
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The 38th Annual Meeting of
the United Kingdom Environmental Mutagenesis Society
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تاريخ الإنعقاد:
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12-15/07/2015
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مكان
الإنعقاد:
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Plymouth, UK
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طبيعة المشاركة:
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Poster Presentation
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عنوان المشاركة:
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The stromal cell line HS-5
is an alternative mesenchymal stem cell source for the development of a 3D
bone marrow model
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ملخص المشاركة:
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Developing a novel three-dimensional
(3D) in vitro model of the bone
marrow microenvironment using bone marrow mesenchymal stem cells (BM-MSCs) in
commercial matrices involves a series of distinct processes. This starts with
selecting an appropriate cell source and growth environment. Primary cells
isolated from healthy donors have low proliferation rate and lack homogeneity
that can result in experimental variation. This study evaluated the
immortalized stromal cell line HS-5 as an alternative cell source and evaluated
their behaviour in the 3D culture.
This study compared cell morphology,
plastic adherence and expression of surface markers of HS-5 vs. primary cells.
Also it evaluated culture medium to improve cell growth and preserve cell
characteristics to as close as possible to the in vivo conditions. Inoculation techniques into the matrix (Biomerix,
Nanofiber and Alvetex) was evaluated, as well as cell retrieval from the 3D
system for further investigation.
The results indicate that both HS-5 and
primary cells meet the criteria for MSC demonstrating plastic adherence,
correct cluster of differentiation marker (CD) expression and fibroblastic
morphology, however cells are rounded in 3D culture.
BM-MSCs were not able to penetrate into
the nanofiber, however, HS-5 cells penetrated and grew inside the nanofiber but
with different morphology to cells in other scaffolds. HS-5 grows best in
high glucose DMEM medium supplemented with 11% heat inactivated FBS and 2mM
L-glutamine. Under these conditions HS-5 adhere well to the scaffolds at room
temperature and are easily retrieved using trypsin solution whereas primary
cells need up to 120 and 90 minutes to adhere to Nanofiber and Biomerix
respectively. HS-5 proliferation rate, size and CD expression decreased in
the 3D compared to the 2D. It was noted that some cells escaped the scaffolds
and formed a 2D monolayer. The data confirms HS-5 as a suitable alternative
cell source for 3D culture.
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المؤتمر (5):
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عنوان المؤتمر:
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The 38th Annual Meeting of
the United Kingdom Environmental Mutagenesis Society
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تاريخ الإنعقاد:
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12-15/07/2015
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مكان
الإنعقاد:
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Plymouth, UK
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طبيعة المشاركة:
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Oral Presentation
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عنوان المشاركة:
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Determination of the
appropriate reference gene for real-time PCR analysis of the immortalized
stromal cell line HS-5 in 2D and 3D culture following melphalan exposure
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ملخص المشاركة:
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Although gene expression analysis using
real-time quantitative reverse transcription-polymerase chain reaction
(RT-qPCR) is an accurate method to evaluate cell activities and phenotypes,
the reliability of the analysis depends on the selection of appropriate
reference gene(s) that are highly expressed and stable in experiments. Cell
behaviour and gene expression depend on the culture environment where three
dimensional (3D) cultures have significant impact on cells compared to the
traditional two dimensional (2D).
In this study, expression and stability
of 12 common reference genes were evaluated in the immortalized stromal cell
line HS-5 in 2D and 3D (Biomerix, Nanofiber and Alvetex) cultures. In
addition, gene stability was evaluated in cultures with and without exposure
to 32.8µM Melphalan, for one hour. The stability of the candidate genes were
determined by RT-qPCR with analysis by geNorm and NormFinder.
The most highly expressed genes in
normal culture were: 2D (EIF4A2, 35.3±0.2), Biomerix (EIF4A2, 32.1±0.9),
Nanofiber (ATP5B, 37.05±0.0), and Alvetex (ACTB, 36.641±0.5). However,
melphalan exposed culture was: 2D (CYC1, 38.4±0.7), Biomerix (SDHA,
38.7±0.4), Nanofiber (UBC, 36.9±0.0), and Alvetex (β2M, 36.2±0.09). According
to the stability value determined by Normfinder the highest stability value
without drug was 2D (EIF4A2, 0.01), Biomerix (CYC1/EIF4A2), Nanofiber (YWHAI,
0.055), and Alvetex (YWHAI/18s, 0.206), for the melphalan exposed culture was
2D (YWHAZ, 0.078), Biomerix (YWHAZ/β2M, 0.01), Nanofiber (18s/UBS, 0.123),
and Alvetex (18s/UBS/β2M, 0.213).
In conclusion, culture technique and
treatment have a significant impact on reference gene expression. Thus it is
essential to analyse the housekeeping genes for each experimental condition
to determine the most suitable reference gene to be used within the comparative
analysis of toxicity responses.
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جوائز التكريم:
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الجائزة (1):
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مسمى الجائزة:
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PrimerDesign
Silver Sponsorship packages
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الجهة المانحة:
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PrimerDesign
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تاريخ الجائزة:
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28/02/2014
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مجال التكريم:
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Development
of a 3D model of the human bone marrow for toxicity testing
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