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The phannacokinetic profile of teicoplanin was studied in 12 elderly patients with a moderate degree of renal impairment (mean creatinine clearance, 51·3 ml/h/kg before treatment), after a single 6 mg/kg iv dose. Pharmacokinetic parameters were estimated both by a three-compartment open pharmacokinetic model and by non-compartmental analysis; peak plasma levels, 15 min after administration, averaged 45 mg/l. The half-lives of the two distributive phases were 0·39 and 7·3 h, respectively. The elimination half-life averaged 107 h, with similar estimates obtained from the three-compartment analysis and from urinary data. The volume of distribution from the central compartment was 009 l/kg while the volumes of distribution at steady state and during the elimination phase were 1·3 and 1·6 I/kg, respectively. The total teicoplanin clearance averaged 10·6 ml/h/kg, with renal clearance accounting for about 40% of the total. There was a linear correlation between teicoplanin total or renal clearance and endogenous creatinine clearance. The average total recovery of teicoplanin in urine over eight days was 28%. There were no local or systemic adverse reactions to teicoplanin. [ABSTRACT FROM PUBLISHER]

The pharmacokinetic profile of teicoplanin, a new glycopeptide antibiotic active against Gram-positive aerobic and anaerobic bacteria, is described in five patients with end-stage renal disease on continuous ambulatory peritoneal dialysis (CAPD). A single 3 mg kg-1 dose was given intraperitoneally in the dialysate during a 6 h dwell time. The drug appeared in the plasma within 15 min at 1.00-0.28 mg l-1 (mean +/- s.d. = 0.70 +/- 0.45) in all five subjects, and peak serum concentrations ranged from 5.53 to 2.80 mg l-1 (4.84 +/- 1.43) at 6 h. Approximately 70% (71 +/- 12) of teicoplanin was absorbed from the peritoneal dialysis fluid during a single 6 h dwell time. The rate constant for peritoneal transfer (lambda d) averaged 0.318 h-1 and the half-life (t1/2 lambda d) was 2.18 h. Further values were serum elimination half-life 114-173 h; total body clearance 263-532 ml h-1; steady-state volume of distribution 68-93 l. This drug profile closely agrees with data reported after intravenous injection in patients on CAPD and suggests that teicoplanin has bidirectional exchange characteristics through the peritoneal membrane, although transfer from the systemic circulation to peritoneal fluid is consistently low. Instillation of teicoplanin in CAPD fluid may be a useful route of administration for treatment of peritonitis and exit site infections in CAPD patients. [ABSTRACT FROM AUTHOR]

Liquid Marbles are liquid droplets encapsulated by hydrophobic powder particles; due to their non-wetting nature, they allow to manipulate liquids efficiently. Literature highlighted their potential to be employed as micro-reactors, micro-containers for growing micro-organisms and cells, micro-fluidics devices, and have also been used in the framework of unconventional computing. In this work, we discuss a theoretical implementation of all required components to define a multi-cycle datapath based on Liquid Marbles. Then, we consider issues related to scalability, by discussing how the circuits can be expanded with the growth of the inputs, and also how they can be modified to overcome the issues related to the growing time and space complexity., Competing Interests: NO authors have competing interests., (Copyright: © 2024 Erba et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Daily monitoring of peripheral blood CD34+ cells may not be necessary for all patients with hematologic malignancies for adequate peripheral blood progenitor cells (PBPC) mobilization and harvesting. We therefore designed a regimen for PBPC mobilization in patients with multiple myeloma or pre-treated Non-Hodgkin's lymphoma based on a combination of low-dose cyclophosphamide (Cy) plus granulocyte colony-stimulating factor (G-CSF) without daily monitoring of peripheral blood CD34+ cells., Study Design and Methods: A prospective study was performed on patients with multiple myeloma (n = 22) or pre-treated Non-Hodgkin's lymphoma (n = 17) whose PBPC were harvested according to the following regimen: 1.5 g/m(2) Cy at day 1, 12 microg/kg/day G-CSF from day +7 to +11 avoiding daily monitoring of peripheral blood CD34+ cells and two consecutive leukapheresis at days +12 and +13. The optimum threshold of 2x10(6) CD34+ cells per kg was established., Results: The proportion of patients with higher CD34+ cell yield after two leukapheresis was similar: multiple myeloma (16/22-72.7%) and Non-Hodgkin's lymphoma (12/17-70.6%). Exposure to radiotherapy and greater than two prior chemotherapy regimens were significantly associated with lower yield in multiple myeloma (p = 0.002) and Non-Hodgkin's lymphoma patients (p = 0.002), respectively., Conclusion: Our data suggested that adequate yields of CD34+ cells may be achieved in multiple myeloma or pre-treated Non-Hodgkin's lymphoma mobilized with low-dose Cy plus G-CSF regardless of the daily monitoring of peripheral blood CD34+ cells.

The use of cell culture models, based on human cell lines derived from the intestinal epithelium, is a promising new tool for the in vitro study of oral absorption of drugs. An assay has been developed using the Caco-2 cell line with the aim of studying the in vitro permeability of antibiotics. The reproducibility of the assay conditions have been assessed by means of the transport of two different marker molecules: 3H-mannitol and fluorescein, and transepithelial electrical resistance (TEER) value for cells monolayers. The results show that cells after 21 days of culture give significantly tighter monolayers than those after 15 days with higher reproducibility. Apparent permeability coefficients (Papp) have been measured for 13 antibiotics, known to be absorbed at different rates in humans. Papp values span from 0.18 x 10(-6) cm/s for cephaloridine to 5.79 x 10(-6) cm/s for rifampicin where the corresponding bioavailability values, known from literature, span from < 3 to 98%. A Caco-2 in vitro model appears to be suitable to investigate the transport of drugs across the intestinal epithelium. This model gives no information about the metabolic phase that follows the absorption of a drug but could provide information to investigate its pharmacokinetical behavior.

Teicoplanin, although more active than vancomycin [by minimum inhibitory concentration (MIC)], produces smaller inhibition zones in sensitivity testing with 30-microgram disks. Our data support the hypothesis that this is due to lower diffusion of teicoplanin in agar media. After 6 hr of incubation, approximately 70% of vancomycin, but only 20% of teicoplanin entered the agar from a paper disk charged with 30 micrograms of antibiotic. This is due to a difference between the diffusion coefficients: 0.47 mm2/hr for teicoplanin and 0.72 mm2/hr for vancomycin. With the methodology used in this work, it is possible to calculate the range of concentrations of the antibiotic occurring at times likely to include the critical time--the time when the inhibition zone is formed--of most strains at any given distance from the reservoir. One can thus estimate the breakpoint diameter for a given MIC breakpoint; for example, an MIC breakpoint of less than or equal to 4 micrograms/ml would correspond to a greater than or equal to 15-mm breakpoint diameter for vancomycin (30-microgram disk) and a greater than or equal to 13-mm breakpoint diameter for teicoplanin (30-microgram disk).

After the i.v. administration of a single 10 mg/Kg dose of [14C] teicoplanin to rats, no substantial differences were found between males and females as regards the hematic profile, the excretion pattern and tissue distribution. About 74% of the administered radioactivity was recovered in the 0-120 hours interval and more than 90% of this amount was found in the first 24 hours. In the 0-120 hour interval, 7% of the dose was excreted with the faeces, while the total 14C excreted (including the cage washing) was 82% of the dose. A high affinity of [14C] teicoplanin for the kidneys and especially for the cortex area was displayed in the distribution study. Similar findings were observed when 7 intravenous doses (10 mg/Kg each) were given to male rats at 24 hour intervals. The percentage of the total dose found in urine seven days after the last administration remained close to 70% and also the excretion data observed in each collection interval after the last treatment were comparable with those obtained in the single dose study. The distribution in tissues was very similar to that of the single dose experiment. The high 14C concentration level found in the kidneys of animals killed at 5 min after the last treatment was cleared with a disappearance rate comparable with that observed in the single dose experiment.

A solid phase enzyme receptor assay (SPERA) for teicoplanin has been developed and recently presented in a kit form. The assay relies on the competition between antibiotic present in the biological fluid and peroxidase labelled teicoplanin for albumin-epsilon-amino-caproyl-D-alanyl-D-alanine (BSA-epsilon-ACA-D-Ala-D-Ala), a synthetic analog of the biological receptor. The kit contains BSA-epsilon-ACA-D-Ala-D-Ala coated microplates together with all the necessary reagents. The limit of detection of the SPERA is 0.5 mg 1(-1). The microbiological assay for teicoplanin uses Bacillus subtilis ATCC 6633 as test organism and a high salt medium to ensure a low limit of detection of 0.05 mg 1(-1). The previously established correlation between the two methods has been confirmed using the kits on 280 serum and 216 urine samples with concentrations up to 500 mg 1(-1).