[Contribution of the laboratory to the evaluation of brain-dead patients for obtaining organs from dead individuals].

The removal organ in order to transplantation is realized often for patient deceased. It was regulation activity that passes in urgency context where laboratory play an important role. The biochemistry, immunology, haematology, toxicology and microbiology analysis allows the validation of the donors, the supervision of the functional quality of organ and the definition of the best couple donor-recipient.

[Direct determination or estimated value of plasma ionized calcium : indications and limits].

Calcium plays a fundamental role in many essential for life functions. Ionized calcium (Ca(++) ) represents free fraction and 50% of the total calcium in the plasma is accepted as its physiologically active form. On almost all laboratories, only total calcium is routinely measured, and ionized calcium concentration is calculated based on calcium, protein or albumin concentrations for many plasma sample or with others parameters like pH.

Physico-chemical and pharmacological comparison of pyridoxylated hemoglobin bound to polyoxyethylene or polymerized by glutaraldehyde.

Two modified hemoglobin solutions were assessed using the same physico-chemical and pharmacological techniques. The first was prepared by covalent binding of monomethoxypolyoxyethylene (MPOE) 1.9 kDa to pyridoxylated hemoglobin (PLP-Hb).

Pyridoxylated polymerized hemoglobin solution processing. Interest of a membrane molecular fractionation step.

Glutaraldehyde hemoglobin polymerization gives too many high polymers, resulting in a too viscous solution. We describe here an alternate method leading to superior results, as compared to the classical one. This method includes a molecular fractionation step using a tangential flow ultrafiltration that secondarily lowers the unpolymerized tetramer's content of a mildly polymerized, pyridoxylated hemoglobin solution (Pyr-Poly Hb).

[Platelet preservation in a new type of plastic material. Functional in vitro study].

We report the comparison of the fonctionnal platelet criteria's evolution studied in vitro by aggregation with different agents, by osmotic stress, ATP total amount and platelet volume distribution for six days of storage in two different PVC bags. The results indicate that: platelet's evolution appears more appreciable when tested by aggregation with an important amount of collagen, by hypotonic stress and volume distribution. The difference between the two different bags is shown as early as the thirs day of storage; for quality control, we can choose some criteria despite the absence of their clear correlation with transfusion efficiency.

[Rift valley fever and Zinga virus: a pathogenic arbovirus in man and animal new for Madagascar].

Virus Zinga strains have been isolated from several pools of mosquitoes collected in Perinet area, 130 km far from Tananarive, at the Institut Pasteur of Madagascar in 1980. Although this virus is pathogenic for man, it seemed to give only a mild illness and did not appear to constitute a problem of Public Health. But today it is seen in quite a different way; since the WHO Center for Arbovirus Reference and Research of New Haven has shown the serologic identity between virus Zinga and an another arbovirus, Rift Valley Fever virus.

Arboviruses and lemurs in Madagascar: a preliminary note.

The epidemiological role played by lemurs in the circulation of arboviruses in Madagascar has been studied. From serological (HAI) tests, exposure of lemurs to alphaviruses and flaviviruses appears to vary considerably with location and species of lemur; positive tests varied from 0 to 32%. Finally, the data concerning the lemurophilic part of the mosquito fauna suggests that some lemur species and man are infected by the same arboviruses, especially West Nile virus.