[Technology transfer between academic laboratories and industrial laboratories: licensing]. / Transfert de technologie entre laboratoires académiques et laboratoires industriels: licences de brevets.

SUMMARY: The time when academic and industrial research were operating in two separate worlds is now over. Technology transfer from one to the other is now frequent and organized. It starts by filing a patent. Of course, provided the amounts at stake for developing a product, especially in the healthcare field, a non patent-protected invention has virtually no chance of eventually reaching the community. But this is only the first step of a long process which starts by licensing deals of which we will examine the main common clauses.

Choice of vehicle for three-month continuous intravenous toxicology studies in the rat: 0.9% saline versus 5% glucose.

A study to assess the toxic potential of a candidate-drug administered to unrestrained rats as 1-h infusions thrice daily for 3 months, using 5% glucose as vehicle, had to be aborted on day 34 because of poor physical status and mortalities in all groups, including controls receiving the vehicle alone. Investigation demonstrated an opportunistic infection, probably secondary to the glucose present in the intravenous formulation. A second study using 0.9% saline solution as a vehicle, was successfully completed.

Lymphoproliferative response to mitogen (ConA) after treatment of rats with gentamicin and doxycyclin: relevance to human therapeutics.

Interaction of xenobiotics with the immune system may result in undesirable effects such as immunosuppression. In the future, it is probable that immunological screening tests may be required for safety evaluation of new drug candidates as an adjunct to more traditional toxicity testing. The lymphoproliferative response to mitogens has been proposed as a screening test. This test has been set up and validated in mice, but will probably have to be done in rats, the species of choice for drug safety studies. This test has been adapted to rats, using both in vivo and in vitro treatments, and used to validate drugs, including doxycyclin and gentamicin (with cyclosporin A and hydroxycortisone as controls) at the dose levels used in toxicology studies. Discrepant results obtained with doxycyclin and hydroxycortisone (effect in vitro but not in vivo) suggest that further validation studies are necessary in order to assess the reliability of this test.

Transcriptional mapping of the promoter of the aminoglycoside acetyltransferase gene (aacC9) of neomycin-producing Micromonospora chalcea.

We have studied the promoter of the gene encoding aminoglycoside acetyltransferase (aacC9) in neomycin-producing Micromonospora chalcea. S1 nuclease mapping showed that the transcription initiation point of this gene is at the translation start point, with no evidence of a conventional ribosome-binding site. The aac of paromycin-producing Streptomyces rimosus forma paromomycinus shows the same characteristic; there is no homology in the promoter regions of the two genes, whereas the coding sequences are very similar.

Isolation and characterisation of an aminoglycoside phosphotransferase from neomycin-producing Micromonospora chalcea; comparison with that of Streptomyces fradiae and other producers of 4,6-disubstituted 2-deoxystreptamine antibiotics.

The gene (aphA-5c) encoding for aminoglycoside-O-phosphoryl-transferase (APH(3')-Vc) from Micromonospora chalcea 69-683 was cloned by expression in Streptomyces lividans; it showed strong nucleic and amino acid similarities with previously described streptomycetes aph genes. S1 mapping of the 5' region indicated that, as with several streptomycete genes, transcription apparently initiates at the translation start codon, with no extragenic ribosome binding site. Comparison of the flanking sequences of the actinomycete aph genes indicates considerable divergence, which is not consistent with the notion that clustered biosynthetic genes for structurally related (or identical) antibiotics are disseminated in their entirety between microbial species.

Characterisation of aminoglycoside acetyltransferase-encoding genes of neomycin-producing Micromonospora chalcea and Streptomyces fradiae.

Two genes (aac) encoding aminoglycoside-N-acetyltransferase from Streptomyces fradiae and Micromonospora chalcea were cloned: the former identified by hybridization with a homologous gene from Streptomyces rimosus forma paromomycinus, the second by direct expression in Streptomyces lividans using pIJ702 as a vector. These two genes showed pronounced nucleotide and amino acid sequence similarities between themselves and also between previously described streptomycetes aac genes. Comparison of the flanking sequence of actinomycetes aac genes indicates considerable divergence, contrary to the notion that clustered biosynthetic genes for structurally related antibiotics were disseminated in their entirety between microbial species.

Aminoglycoside acetyltransferase 3-IV (aacC4) and hygromycin B 4-I phosphotransferase (hphB) in bacteria isolated from human and animal sources.

Members of the family Enterobacteriaceae harboring an enzyme of the aminoglycoside acetyltransferase 3 class (AAC-3-IV) (apramycin and gentamicin resistance) and hygromycin B phosphotransferase 4 (HPH-4-I) (hygromycin B resistance) have been isolated from human clinical sources in Europe. A cluster of genes containing IS140, aacC4, and hphB was found in these strains. We demonstrate by Southern hybridization that this cluster is identical to the operon found in animals that also contains insertion sequences belonging to the ISO family. This provides another example of presumptive transfer of antibiotic resistance genes between bacteria of animal and human origin.

[Manual method of assaying plasma hemoglobin by tetramethylbenzidine and deferoxamine]. / Méthode manuelle de dosage de l'hémoglobine plasmatique par la tétraméthylbenzidine et la déferoxamine.

We describe a manual method to determine very low concentrations of hemoglobin in plasma (0,25 to 37,3 mumol/l). We use peroxidase properties of hemoglobin which decomposes hydrogen peroxide releasing oxygen. This released oxygen will oxidize tetramethylbenzidine. The original feature of the proposed method lies in the stabilization of the obtained colour by a complexing agent, the deferoxamine. The technique is quick, reliable, cheap and does not need specialized equipment. It is possible to use the method for urines.