Search PubMed⌕ Search

Biomedical subjects

J Tamalet

Publications and source records attributed to J Tamalet.

At least 19 recordsLinked to original sources

Rapid diagnosis of cytomegalovirus by indirect immunofluorescence assay with monoclonal antibody F6b in a commercially available kit.

Anti-human cytomegalovirus (CMV) monoclonal antibody (MAb) F6b produced by clone 95/12 was used for the rapid diagnosis (16 to 24 h) of CMV isolates in 308 clinical specimens and compared with classic isolation. MAb F6b gave 100% correlation with isolation. When this MAb was used for direct diagnosis with 212 urine and bronchoalveolar specimens, detection of CMV varied from 50 to 75% compared with viral isolation.

Antibodies, Monoclonal↗

In vitro evaluation of josamycin, spiramycin, and erythromycin against Rickettsia rickettsii and R. conorii.

The antimicrobial activities of josamycin, erythromycin, and spiramycin against Rickettsia conorii and R. rickettsii were evaluated in two tests: a dye-uptake assay and a plaque assay. The MIC of josamycin was 1 microgram/ml for both species; the MICs of erythromycin and spiramycin were 4 to 8 and 16 to 32 micrograms/ml, respectively, for both species. Only josamycin may be of clinical use in treating spotted fever rickettsiosis. It may be useful in treating pregnant women and young children.

Animals↗

Susceptibility of Rickettsia conorii and R. rickettsii to pefloxacin, in vitro and in ovo.

The activity of pefloxacin against Rickettsia conorii and R. rickettsii was determined by several methods. The mean survival time of embryonated eggs infected with R. conorii was increased by pefloxacin 50 micrograms/egg; plaque formation in Vero cells was inhibited by 1 mg/l. In a microplate assay, the MIC of pefloxacin was 0.5 mg/l for R. conorii and 1 mg/l for R. rickettsii. The results support the use of pefloxacin in treating spotted fever rickettsioses.

Animals↗

[Role of phagocytes in experimental scrapie in hamsters].

We studied the interactions between scrapie agent and hamster's phagocytic cells. Macrophages which have been in contact with the scrapie agent are able to carry the infectivity of this agent. We induced variations of different parameters involved on fixation and phagocytosis and we did not observe any modification. A depletion of phagocytic cells induced in hamster at the entry of scrapie increase the incubation time of the illness. Furthermore phagocytic cells cocultured with glial cells seem to be able to transfer infectivity to glial cells. So scrapie agent and hamster's reticulo-endothelial system probably interact at three levels: first at the entry, then during haematogenous diffusion of scrapie agent and finally nearly the central nervous system.

Animals↗

In vitro susceptibility of Rickettsia conorii to ciprofloxacin as determined by suppressing lethality in chicken embryos and by plaque assay.

We tested the susceptibility of Rickettsia conorii to ciprofloxacin, a new quinolone antibiotic. A final concentration of 1 microgram/g of egg was effective in suppressing chicken embryo lethality, and a concentration of 0.25 micrograms/ml inhibited plaque formation in a plaque assay; however, a concentration of 0.5 microgram/ml was necessary to obtain rickettsiacidal activity. These results support the idea that ciprofloxacin could be of clinical use in treating Mediterranean spotted fever.

Animals↗

[Chlamydia trachomatis cervicitis].

Cervicitis due to Chlamydia trachomatis is common in certain groups of women examined by the authors. It is clinically discrete, having no special characteristics and often not even showing clinical manifestations. However, it is the stage of infection of the genital apparatus which it is desirable to detect in order to prevent the serious tubal complications to which a too large number of young women is subject. Clinical medicine permits diagnosis and prescribes treatment for patients and, if possible, their partners. The principal difficulty is to know when to invoke them.

Adolescent↗

Changes in the nigrostriatal system following microinjection of an unconventional agent.

The effect of apomorphine, a direct dopamine receptor agonist, was studied in golden hamsters after unilateral injection of scrapie agent (strain 263K) into the nigrostriatal system. Twenty-five received an injection into the left striatum and 24 into the left substantia nigra. Varying volumes (5, 1 and 0.5 microliterss) and dilutions of the homogenate (10(-2), 10(-3), 10(-4)) were used. The duration of the incubation period (delay of appearance of clinical signs of the disease) was dependent on the dose of the agent used: it varied within a range of 72 +/- 5 days (5 microliter 10(-4) and 123 +/- 8 days (0.5 microliter 10(-4)). Apomorphine-induced circling behavior appeared after an average of 84 +/- 15 days post-injection and this delay was closely related to the dose of agent. The direction of the rotation dependent on the site of injection: most of the animals circled towards the inoculated side after striatal injection and away from it after inoculation in the substantia nigra. In the group of animals inoculated in the substantia nigra with 0.5 X 10(-4) microliters, 6 presented the clinical phase of the disease and showed circling behavior but no clinical signs when they were killed 200 days post-injection. However, neuropathological studies revealed characteristic foci of vacuolation in the brain stem. Apomorphine-induced circling behavior can only be contained by replication of scrapie agent into the nigrostriatal neurons and the subsequent imbalance between the two sides which it reveals. Circling behavior and clinical signs of the disease can be temporally dissociated: low doses of agent slightly extended the circling behavior latency, whereas the incubation period was considerably increased. Circling behavior and neuropathological lesions in nigrostriatal system were not closely related.

Animals↗

Apomorphine-induced circling behaviour in hamsters following unilateral injection of scrapie gent in the striatum.

Twenty golden hamsters received a microinjection of scrapie agent into the left striatum. At different times after inoculation animals were injected intraperitoneally with apomorphine, a direct dopamine receptor agonist. Two types of effects developed simultaneously, starting at about 80 days after infection. First, apomorphine induced a rotational behaviour which showed a progressive destruction of the striatal neurones at the site of injection. This suggest a local spread of scrapie agent by cell to cell transfer in the striatum. Secondly, the clinical signs of scrapie developed, indicating a more widespread distribution of agent throughout the brain.

Animals↗

Experimental kuru in the rhesus monkey. A clinical study.

Serial neurologic examinations of six rhesus monkeys inoculated with a strain of kuru revealed complex clinical signs falling into two distinct syndromes. Experimental kuru in the rhesus monkey is different from the disease in man and to a lesser extent in the chimpanzee. Two factors are proposed to account for these observations: modification of the strain, and specific host characteristics.

Animals↗