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F Marcenac

Publications and source records attributed to F Marcenac.

10 recordsLinked to original sources

[The impact of HIV infection on the incidence of syphilis and gonorrhea at a university hospital (1985-1994)].

Syphilis and gonorrhea are two sexually transmitted diseases (STD) which still persist in spite of the existence of effective treatment. In this paper the incidence of these two diseases was evaluated between 1985-1994, a decade during which the problem of HIV infection arose. Every patient who attended the STD Program at the Hospital and was suspected of having syphilis and/or gonorrhea was clinically evaluated and was subjected to the following tests: a) search for Neisseria gonorrhoeae (Ng) and penicinilase producers (PPNG) identification, b) search for Treponema pallidum (Tp) by darkfield microscopy, c) serological studies for syphilis. From 1985 to 1991 the average of positive cases for Ng was 14.8% while from 1992 to 1994 it was 4.0% (p < 0.0001) showing a dramatic decrease between 1991 and 1992. PPNG increased from 8.7% in 1985 to 44.6% in 1988 and then slowly decreased down to 26.9% in 1994. From 1985 to 1990 the average of positive darkfield examinations was 20.7% while from 1991 to 1994 it was 12.2% (p < 0.0001). Between 1985 to 1988 syphilis serological studies showed 45.7% positive cases dropping to 34.3% between 1989 and 1994 (p < 0.0001). HIV infection appearance had a wide repercussion throughout the world generating behavioral and sexual habit changes which have probably helped to prevent these two STD. Gonorrhea incidence was also influenced by the appearance of new effective treatments, even against PPNG, such as fluorated quinolones and third generation cephalosporines. The population studied belongs to the most crowded area in Argentina, so that these observations should not be extrapolated to the rest of the country.

Adolescent↗

[Ceftizoxime: in vitro evaluation].

The effect of ceftizoxime, a new aminothiazolil-syn-methoxy-iminocephalosporin has been evaluated on 169 strains of Gram negative bacilli isolated from hospitalized patients and compared with that of cefotaxime and of ceftriaxone. The effect of these 3 cephalosporins and of cefalotin was also evaluated on 50 strains of staphylococcus. CIM50 of ceftizoximel was as follows: K. pneumoniae less than .032, aureus and S. epidermidis less than .2 CIM90 for the same species was: K. pneumoniae less than .25, E. coli less than .63, E. Cloacae and S. marcescens less than 8, S. aureus less than 32, S. epidermidis less than 16. The values obtained with cefotaxime and ceftriaxone were similar. Cefalotin was clearly more active on staphylococcus strains with CIM50 and CIM90 for both species of less than .25 and less than .2 respectively.

Cefotaxime↗

Effect of l-tetrahydropalmatine on dopamine release and metabolism in the rat striatum.

In vivo voltammetric measurements of striatal extracellular DOPAC concentrations and of striatal DA release in combination with post-mortem analysis of striatal catechols were performed in the rat to study the effects on the nigro-striatal neurons of a Chinese neuroleptic, l-tetrahydropalmatine (l-THP), which is known to block post-synaptic dopaminergic receptors. l-THP injected at doses that cause sedation in rats and mice (5-10 mg/kg) induced a marked increase in post-mortem DOPAC levels (+250%), while no significant effect was observed on postmortem DA levels. The extracellular DOPAC concentration was increased to 155 +/- 9% of the control value after l-THP administration (1 mg/kg, IP). Further, an injection of l-THP (1 mg/kg, IP) induced an increase in extracellular DA concentration (220% of the basal value), reversed the decrease in extracellular DA concentration induced by apomorphine (0.05 mg/kg, SC) and enhanced the effects of the electrical stimulation of the nigro-striatal pathway. These results confirm that l-THP acts on the nigro-striatal neurons as a dopaminergic antagonist that can block both post- and presynaptic receptors.

3,4-Dihydroxyphenylacetic Acid↗

Endogenous platelet serotonin release monitored during aggregation by means of a new electrochemical technique.

Differential pulse voltammetry combined with electrochemically treated carbon fibre microelectrodes was used to monitor endogenous serotonin release occurring during platelet aggregation. After platelet stimulation by thrombin, an oxidation peak was recorded at +280 mV. HPLC analyses performed with fluorimetric detection have shown that this released electroactive compound was essentially serotonin. Moreover, serotonin measurements in the same samples by the technique reported here and by fluorimetry were found to be very similar (1.15 +/- 0.30 microM and 1.17 +/- 0.15 (mean +/- S.D., n = 6), respectively). Extracellular serotonin concentrations could be estimated either directly during aggregation or in supernatants obtained from stimulated or lysed platelets. Maximal serotonin concentrations have been found to be 6.93 +/- 0.37 and 3.28 +/- 0.39 nmol/10(9) platelets from rat and human, respectively. Using the reported procedure, we have observed that no serotonin was released from thrombin-stimulated platelets prepared from rats treated with reserpine. Our new technique represents a selective and performant tool for rapid determination of endogenous serotonin platelet secretion.

Animals↗

[Presence of resistance factors to antibiotics in multiresistant enterobacteria].

The present study was carried out with 111 multiresistant pathogenic strains of enterobacterias isolated from different sources with increased resistance to three or more antibiotics. Among the identified species are included E. coli, Shigella sp., Salmonella oranienburg, Klebsiella pneumoniae and Citrobacter freundii. In general, the minimal inhibitory concentration of antibiotics was above 100 microgram/ml and in some cases it was superior to 1000 microgram/ml. Resistance transfer factors were detected in 72% of the strains; 33% movilized the complete pattern of resistance and 67% did it partially because some of the determinants were not transfered. The Citrobacter strains show a high frequency of transference (10(-1)), while for the others species it was in the order of 10(-2)--10(-3). The use of a multi-inoculator allows to perform in a simple way the preliminar evaluation about the presence or absence of R transfer factors in multiresistant strains. This technique has shown good correlation with the data obtained by the usual dilution and plating method.

Animals↗

[Enteral nutrition: reduction in the contamination risk].

Enteral nutrition is used as a routine therapy in patients with caloric-protein malnutrition, severe dysphagia, major burns, intestinal resection, and enterocutaneous fistulae, as long as a portion of the digestive tract still has an active absorptive function. The administration takes place by means of surgical (ostomies) or non-surgical (nasogastric) tubes. In our country, a significant number of hospitalized patients with various diseases receive this type of nutrition. Given that the colonization of the digestive tract by hospital flora is the first step towards developing intra-hospital infections, the contamination implies serious risks. The objective of this study was to study the most appropriate conditions for the manufacturing, storage and administration of the mixture of nutrients of enteral nutrition, to guarantee nutrition with a lower contamination risk. This study was conducted by the Unit of Nutritional Assistance of the Mater Dei Clinic, by means of bacteriological controls, from January 1991 to December 1992, and in 1993 in which the work systematics were reviewed. The study was prospective, and those solutions whose bacteriological counts were lower than 100.000 colony forming units (CFU), and which showed an absence of enteropathological micro-organisms, were considered acceptable, and those solutions which had a bacteriological count greater than or equal to 100.000 CFU and or the presence of enteropathological micro-organisms, were considered unacceptable. During the first period, "usual working conditions", we analyzed the infra-structure, the personnel, the constituents, and the apparatus used in the manufacturing, for which 36 samples were studied at t0 (moment of preparation). Afterwards, in the second period "special working conditions", we analyzed the manufacturing procedures, the storage and the administration of 103 solutions, corresponding to 36 patients, taking samples at t0 and t24 (after 24 hours of preparing). In the first phase, we found a 53% contamination. In the second phase, 99.03% of the solutions were within the limits of acceptability, and only 0.07% were unacceptable. We conclude that it is necessary to have access to a working area which meets the biosecurity norms, to use sterile technique in the preparation, to prefer pharmacologically sterile products for the preparation, to store the prepared mixture between 4 and 8 degrees C, and to keep it cooled during the administration. Lastly, we saw the need to continuously capacitate the nursing, dietary (ABSTRACT TRUNCATED)

Argentina↗