196,061 research outputs found
Pharmacokinetics of Fluconazole in Normal Volunteers
No full textThe pharmacokinetic profile of fluconazole, after 100 mg i.v. infusion or oral administration of a single 50 mg or 150 mg dose, was investigated in 18 healthy volunteers. At a dose of 100 mg i.v., the half-life (t( 1/2 β)) was 29.73 ± 8.05h. The mean residence time in the plasma was 27.56 ± 5.98 h. The post-distributive volume V(β) = 52.16 ± 9.83 l, approximating that of total bodywater. Renal excretion accounted for 61.64 ± 8.80% of the drug elimination after 48 h, with renal clearance Cl(r) = 12.91 ± 2.83 ml/min. Plasma clearance (Cl(r)) was 21.03 ± 5.07 ml/min. At oral doses of 50 and 150 mg the distribution and elimination of fluconazole resembled that following i.v. infusion. The peak levels in plasma at 2.5 h were 0.93 ± 0.13 and 2.69 ± 0.43 μg/ml, respectively. The large distribution volume, the long half-life and mean residence times, combined with a rapid absorption after oral administration, suggest that fluconazole will be effective at a wide range of body sites
A linear model for the pharmacokinetics of azithromycin in healthy volunteers
No full textThe pharmacokinetic profile of azithromycin, after oral ingestion of 500 mg, was determined in 10 healthy volunteers. Statistical and biochemical reason seemed to indicate a zero-order absorption of the drug. The disposition of azithromycin was described by a two-compartment model (plasma compartment and extravascular compartment) with elimination from the plasma compartment. The absorption process ends abruptly after a time T = 2.3 ± 0.49 h, from the administration. The transfer rate constant from the plasma compartment to the extravascular compartment (k12 = 0.12 ± 0.04 h-1) and the mean residence time of the drug in the extravascular compartment (MRT2 = 43.53 ± 13.80 h) indicate a rapid and extensive distribution of azithromycin from the serum into the extravascular fluids. The results confirmed the efficacy of a single daily dose of 500 mg per os for clinical use
Pharmacokinetics of Sulbactam/Ampicillin in Humans after Intravenous and Intramuscular Injection
No full textWe investigated the pharmacokinetic properties of sulbactam/ampicillin (S/A), after intravenous (0.5/1.0 and 1.0/2.0 g) and intramuscular (0.5/1.0 g) coadministration in 10 male subjects. After 1.0/2.0 g intravenous doses of S/A the half-lives (t( 1/2 β)) were 1.14 ± 0.14/1.09 ± 0.16 h. The values for plasma clearance (Cl(p)) were 198.83 ± 26.27/250.33 ± 39.28 ml/min and the renal clearance (Cl(r)) 173.50 ± 19.66/208.80 ± 26.43 ml/min. The post distributive volumes (V(β)) were 19.67 ± 3.24/23.56 ± 5.76 liters. Similar values were obtained after 0.5/1.0 g of S/A intravenous coinjection. After 0.5/1.0 g intramuscular coadministration the t( 1/2 β) values were 1.26 ± 0.18/1.20 ± 0.15 h. The values for Cl(p) were 208.00 ± 28.73/243.17 ± 33.24 ml/min, for Cl(r) 179.50 ± 20.26/202.67 ± 27.61 ml/min and for V(β) 22.27 ± 4.12/25.30 ± 4.87 liters. The renal clearance of sulbactam is comparable to that of ampicillin and both clearances are greater than the glomerular filtration rate, suggesting active renal tubular secretion of the two drugs. The large volumes of distribution, and the ratio K12/K21 = 0.5 show the extensive distribution of the two drugs into extracellular fluids. The very similar values of the pharmacokinetic parameters of sulbactam and ampicillin confirm that the kinetics of the two drugs closely resemble one another
In vitro extracellular and intracellular activity of two newer and two earlier fluoroquinolones against Listeria monocytogenes
No full textTwo new fluoroquinolones (trovafloxacin and sparfloxacin) with enhanced activity against gram-positive pathogens and two earlier compounds (ciprofloxacin and ofloxacin) were tested for their in vitro inhibitory and bactericidal activity against 80 strains of Listeria monocytogenes. All strains were uniformly highly susceptible to trovafloxacin, the MIC90 being 0.25 mg/l. Resistance to sparfloxacin was not detected, however the MIC90 of sparfloxacin was eight times that of trovafloxacin. A few strains were resistant to ciprofloxacin and ofloxacin (MIC90 4 mg/l for both drugs). MBCs usually exceeded MICs by 2 to 4 times. The MBC90 of trovafloxacin (1 mg/l) was lower than that of the other three drugs (8 mg/l). After checking their ability to enter and grow within human enterocyte-like Caco-2 cells, four strains were used to study the intracellular activity and eradicating power of the four quinolones. Trovafloxacin was more active than sparfloxacin and the earlier fluoroquinolones in terms of both intracellular killing and inhibition of a cytopathogenic effect. The uniform high-level activity of trovafloxacin against Listeria monocytogenes isolates in conventional in vitro assays and its extracellular and intracellular killing of invasive strains suggest that this and maybe other new fluoroquinolones should be further investigated as possible anti-listerial agents
Antibodies anti-HTLV III and lymphocyte subsets of high risk subjects.
No full text208 assay for the research into anti-HTLV III antibodies and lymphocytes subsets were carried out on the same number of patients at risk. 11 homosexual man, 143 intravenous drug users (i.d.u.) and 3 children of drug addicts from hospitals in the Marche and Abruzzo and 51 haemophiliacs from hospital in Florence were examined. 3 determination of anti-HTLV III antibodies were taken from each subject using 3 different commercial Kits. The results concur with and confirm similar epidemiological studies that have been done. The haemophiliac group had the highest positive percentage (39.2%), then came i.d.u. (11.9%) and the homosexuals (10.0%). Furthermore, of the 38 positive totals, there were 22 with only one kit, 18 with two, and 15 with all three. The evaluation of the lymphocyte subsets did not strictly correlate with the presence of the antiretrovirus antibodies
Activity of ceftibuten, cefaclor, azithromycin, clarithromycin, erythromycin and telithromycin against Streptococcus pyogenes clinical isolates with different genotypes and phenotypes
No full textBackground: The growing number of macrolide-resistant strains of Streptococcus pyogenes represents an increasing worldwide problem. Macrolide resistance in S. pyogenes is mediated by several different genes, which determine different levels of resistance to macrolides, lincosamides and streptogramin B (MLS). Methods:This study compared the in vitro antimicrobial activity of azithromycin, clarithromycin, erythromycin, ceftibuten, cefaclor, and telithromycin against 287 strains of S. pyogenes by the broth microdilution method. All strains were characterized both phenotypically and genotypically for erythromycin resistance and most of them have been M-typed by means of PCR. Results: Ceftibuten and cefaclor showed the best antimicrobial activity, while MIC values for telithromycin were higher against constitutively MLS (cMLS)-resistant strains rather than against the other phenotypes. Conclusion: Oral cephalosporins retain the best activity against S. pyogenes; showing good activity except for cMLS-resistant strains, telithromycin is a valid alternative to these antimicrobials
Distribution of mef(A)-containing genetic elements in erythromycin-resistant isolates of Streptococcus pyogenes from Italy.
No full textIn total, 124 Streptococcus pyogenes isolates were obtained from throat cultures of different symptomatic patients. All isolates showed M-phenotype macrolide resistance and contained the macrolide efflux gene mef(A). The isolates were screened for the presence and insertion site of mef(A)-containing genetic elements. In 25.8% of the isolates, mef(A) was found to be carried by elements belonging to the Tn1207.3/Phi10394.4 family inserted in the comEC gene, while 74.2% contained chimeric elements with a different genetic structure and chromosomal location, probably associated with the recently described 60-kb tet(O)-mef(A) element
Body and didactic mediation: experimental use of a Sense Wear Armband in a university context
No full textThe aims of this study was to understand whether instruments used for motion analysis can detect significant information about the processes of learning and teaching. Moving from Enactivism and the awareness of the embeddedness of the brain in the body and world during cognition, we tested a tool that provide data related to caloric and energetic expenditure of subject (Sense Wear Armband) in a non specialistic school setting, to understand if it is possible to detect the effective bodily participation during cognitive processes (in our experiment, during didactic mediation). For starting the experiment within using a Sense Wear Armand we monitored the activity of didactic mediation done by the professor to detect the energetic expenditure, compared with the other kinds of activities during the day; we also monitored two volunteers students that followed the lectures. Data of every lecture were then elaborated by the specific Sense Wear Software and shown through graphs that we analyzed. Graphs showed that didactic mediation developed as a succession of dynamic and static moments, with different levels of energetic expenditure; what we found interesting is that a minimal but not negligible component of metabolic activity seem to be involved even in essentially intellectual activities. This paper describes only the first step with the first results of our work. The analysis performed here has only an exploratory value and we think it might be useful to the development of the experiment; we don’t believe we have obtained definitive results, but only useful information for the development of the survey. We hope to move forward as soon as possible
- …
