Theo Bijma

Mr. Theo Bijma

orcid

Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 November 2004 in Bioinformatics
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Journal Article
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Patrick KemmerenPatrick Kemmeren
Patrick Kemmeren
TKThessa T. J. P. Kockelkorn
Thessa T. J. P. Kockelkorn
TBTheo Bijma
Theo Bijma
RDRogier Donders
Rogier Donders
FHFrank C. P. Holstege
Frank C. P. Holstege
Motivation: Determining gene function is an important challenge arising from the availability of whole genome sequences. Until recently, approaches based on sequence homology were the only high-throughput method for predicting gene function. Use of high-throughput generated experimental data sets for determining gene function has been limited for several reasons. Results: Here a new approach is presented for integration of high-throughput data sets, leading to prediction of function based on relationships supported by multiple types and sources of data. This is achieved with a database containing 125 different high-throughput data sets describing phenotypes, cellular localizations, protein interactions and mRNA expression levels from Saccharomyces cerevisiae, using a bit-vector representation and information content-based ranking. The approach takes characteristic and qualitative differences between the data sets into account, is highly flexible, efficient and scalable. Database queries result in predictions for 543 uncharacterized genes, based on multiple functional relationships each supported by at least three types of experimental data. Some of these are experimentally verified, further demonstrating their reliability. The results also generate insights into the relative merits of different data types and provide a coherent framework for functional genomic datamining. Availability: Free availability over the Internet. Contact:f.c.p.holstege@med.uu.nl Supplementary information:http://www.genomics.med.uu.nl/pub/pk/comb_gen_network

6 February 2025 in Diagnostics
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Journal Article
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EBEddy de Boer
Eddy de Boer
NCNicole Corsten-Janssen
Nicole Corsten-Janssen
EWElles Wierenga
Elles Wierenga
TBTheo Bijma
Theo Bijma
JKJurjen Knapper
Jurjen Knapper
CDCleo C. van diemen
Cleo C. van diemen
Background: In prenatal genetic diagnostics, the detection of single-gene defects relies on chorionic villus sampling (CVS) and amniocentesis, which carry a miscarriage risk of 0.2–0.3%. To mitigate this risk, fetal trophoblasts have been isolated from a Papanicolaou smear using Trophoblast Retrieval and Isolation from the Cervix (TRIC). However, this method is labor-intensive and has been shown to be challenging to implement in clinical practice. Here, we describe our experiences in using semi-automated immunomagnetic cell sorting for isolating trophoblasts from clinically obtained Papanicolaou smears during ongoing pregnancies. Methods: Using HLA-G-positive Jeg-3 and HLA-G-negative HeLa cell lines in 10%, 1%, and 0.1% dilutions, we tested and optimized the isolation of HLA-G-positive cells using FACS and semi-automated immunomagnetic cell sorting. We used the latter technique for isolation of HLA-G-positive cells from Papanicolaou smears collected from 26 pregnant women, gestational age between 6 and 20 weeks, who underwent CVS. Results: In four independent dilution series, the mean percentages of Jeg-3 cells went from 7.1% to 53.5%, 0.9% to 32.6%, and 0.4% to 2.6% (7.5, 36, and 6.5-fold enrichment, respectively) using immunomagnetic cell sorting. After sorting of the Papanicolaou smears, HLA-G-positive cells were moderately increased in the positive (14.61 vs. 11.63%) and decreased in the negative fraction (7.87 vs. 11.63%) compared to baseline pre-sorting. However, we could not identify fetal cells using XY-chromosomal FISH in a male sample. Conclusions: Our study supports previous findings that careful sampling of fetal cells from Papanicolaou smears in a clinical context poses significant challenges to cell retrieval.

3 August 2026 in Journal of Translational Autoimmunity
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Journal Article
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ASAnne-Lise Strandmoe
Anne-Lise Strandmoe
CBCarlo Bonasia
Carlo Bonasia
NINanthicha Inrueangsri
Nanthicha Inrueangsri
WAWayel H. Abdulahad
Wayel H. Abdulahad
ISInge M. Strating
Inge M. Strating
PHPeter Heeringa
Peter Heeringa