Biomedical subjects

S Badaoui

Publications and source records attributed to S Badaoui.

7 recordsLinked to original sources

PubMed1999

Relationships between proteasomes and viral gene products.

The interrelationships between proteasomes and viral gene products are very complex. 20S proteasomes associate with a number of viral mRNAs which are cleaved by proteasome's associated endonuclease activity. In addition proteasome's endopeptidase activities are involved in the presentation of viral antigens. Viral proteins of different origin associate with the 20S and 26S complexes and interfere with their enzymatic activities. A major part of this review deals with the interactions between 20S proteasomes and the gene products of the human immunodeficiency virus (HIV) which has been studied in detail by our group.

Adenosine Triphosphatases↗

PubMed1995

Relationships between proteasomes and RNA.

The 20S proteasome (prosome) is a highly organized multi-protein complex with approximate molecular weight of about 700 kDa. Whilst the role of the proteasome in the processing and turnover of cellular proteins is becoming clearer, its relationship with RNA remains obscure. Over the last decade the possibility of association of proteasomes with specific RNAs or mRNPs have been particularly controversial. Proteasomes were reported to inhibit translation of viral mRNAs and to be tightly associated with RNase activity. It is possible that proteasomes are also involved in cellular RNA breakdown and RNA processing like prokaryotic RNase E.

Animals↗

PubMed1994

Expression of lactic dehydrogenase isoenzymes in rabbit muscle during development.

1. Rabbit cDNA probes for H and M lactic dehydrogenase subunits were used to monitor mRNA levels in different muscle types during growth. 2. At the same time, lactic dehydrogenase activity and relative quantities of H and M protein subunits were measured. 3. The main results are that mRNA abundance depends on muscle type and age, and mRNA abundance is not correlated with enzymatic activity.

Age Factors↗

PubMed1993

Glycosylation and deglycosylation of proteasomes (prosomes) from calf-liver cells: high abundance of neuraminic acid.

Proteasomes (prosomes) of calf-liver cells were probed with three different biotinylated lectins: Limulus polyphemus agglutinin (LPA), specific for neuraminic acid; Solanum tuberosum agglutinin (STA), specific for GlcNac; and concanavalin A (Con A), specific for Man/Glc. While only one proteasomal protein reacted with STA, most of the proteasomal proteins reacted with LPA and several with Con A. Deglycosylation with N-glycosidase F showed that the detected glycan residues were asparagine-linked. Finally we demonstrate an alternative method for the isolation of proteasomes based on the affinity of certain proteasomal proteins to Con A.

Animals↗

PubMedDate not supplied

Fractures of the medial condyle of the humerus in children.

Twenty-seven cases of fractures of the medial condyle of the humerus in children were grouped into one of three types, based on displacement of the medial condyle on initial roentgenograms. Results after an average follow-up of 2.2 years showed that children less than 5 years old tended to have undisplaced fractures giving rise to good results. Older children tended to have more severely displaced fractures. Good results were obtained in patients who were seen early after injury and who had adequate reduction of their fractures. In cases seen late, proper reduction and immobilization are necessary to achieve satisfactory results.

Age Factors↗

PubMedDate not supplied

Design and implementation of a biomedical image database (BDIM).

We developed a biomedical image database (BDIM) which proposes a standardized representation of value arrays such as images and curves, and of their associated parameters, independently of their acquisition mode to make their transmission and processing easier. It includes three kinds of interactions, oriented to the users. The network concept was kept as a constraint to incorporate the BDIM in a distributed structure and we maintained compatibility with the ACR/NEMA communication protocol. The management of arrays and their associated parameters includes two distinct bases of objects, linked together via a gateway. The first one manages arrays according to their storage mode: long term storage on optionally on-line mass storage devices, and, for consultations, partial copies of long term stored arrays on hard disk. The second one manages the associated parameters and the gateway by means of the relational DBMS ORACLE. Parameters are grouped into relations. Some of them are in agreement with groups defined by the ACR/NEMA. The other relations describe objects resulting from processed initial objects. These new objects are not described by the ACR/NEMA but they can be inserted as shadow groups of ACR/NEMA description. The relations describing the storage and their pathname constitute the gateway. ORACLE distributed tools and the two-level storage technique will allow the integration of the BDIM into a distributed structure, Queries and array (alone or in sequences) retrieval module has access to the relations via a level in which a dictionary managed by ORACLE is included. This dictionary translates ACR/NEMA objects into objects that can be handled by the DBMS.(ABSTRACT TRUNCATED AT 250 WORDS)

Database Management Systems↗

PubMedDate not supplied

A database manager of biomedical images.

In order to allow an efficient archiving and retrieval of biomedical images, PACS would include an image DBMS. As biomedical images have complex structures we developed a specific DBMS over a relational one. The medical image database manager ensures a data description that takes into account data semantics so that consistency or existential constraints may be verified. It provides a unique language to retrieve images no matter what their storage format. It encompasses the queries of the user which constitute a filter over associated data. The manager can handle changes in the environment of the image. We implemented a manager prototype to show the validity of logical access possibilities. The user need no longer know the structure of the image database to access data. The logical access allows retrieval of images, whatever the architecture of the base. An automatic query construction consists of three functional levels including the interfaces towards the external environment which ensure a logical independence from the database, a query generator which creates the correspondence between the user's query and physical access queries, a dictionary which contains the structure of the image data and consistency constraints.

Computer Systems↗