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Abstract

The preparation of CpRu(MeCN)3PF6 using an easily assembled continuous flow reactor is described. This scalable, reproducible method provides the title compound in excellent yield and purity, and eliminates the need for any purification steps. Under our optimized conditions, the residence time required for complete conversion was only 5 min at an initial substrate concentration of 0.06 M, as compared to a reaction time of 12–36 h for the batch process at 0.02 M. This threefold increase in concentration and significant decrease in reaction time increases the throughput and efficiency of the synthesis. Using the simple laboratory equipment described herein, ruthenium catalyst of >99% purity was produced with a throughput of 1.56 g/h (5 mL reactor), which is 10 times the highest reported throughput for the batch process.

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Pharmacokinetic variables of amikacin in cows were determined after administration of amikacin sulphate either intravenously (IV) or intramuscularly (IM) at a dose of 25 mg/kg per day for three days. Amikacin concentrations at time zero and maximum serum concentrations were 240.8 µg/mL and 122.53 µg/mL, respectively. The elimination half-life remained unchanged during the three days of administration (T½ß = 1.33 ± 0.029 h for the IV route and T½ß = 2.75 ± 0.38 h for the IM route). Apparent volumes of distribution suggest limited distribution out of the central compartment (VdAUC = 0.154 ± 0.005 L/kg; Vdc = 36.50 ± 2.35 L; Vdss = 0.092 ± 0.004 L/kg). Bioavailability after IM administration was 95%. Serum profiles of urea, creatinine, albumin, electrolytes and pH after 5-day treatment with amikacin at a dose of 25 mg/kg per day IM revealed no changes. Assessment of diffusion of amikacin to milk by a commercially available screening method to detect antibiotic residues revealed that amikacin could not be detected by the fifth milking period after the last treatment. These results suggest that it would be rational to use a large single-daily dose of amikacin for future clinical trials in cows.

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Abstract  

A great variety in retention properties occurs as a result of different methods of preparation of the sorbents. Specific surfaces and porosities, which are mostly connected with the sorption activities, may vary widely. The activation of Al2O3, SnO2 and silica gel, to produce highly active sorbents occurs only if the oxide is contacted with acid immediately after thermal treatment. The efficiency of the separation scheme has been tested using uranium and fission products under static conditions from strongly alkaline aqueous solutions.

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Excess molar enthalpies,H E , at atmospheric pressure and 303.15 K are reported for binary mixtures of 1-chlorohexane with diethyl oxalate, diethyl malonate, diethyl succinate, diethyl glutarate, diethyl adipate, diethyl pimelate and diethyl sebacate. These experimental results, together with those obtained previously on the excess enthalpies of aliphatic diester+n-hexane mixtures, are interpreted in terms of molecular surface interactions between aliphatic, chlorinated and carboxylate groups. Comparison of the enthalpy interchange parameters reveals a decrease of the intermolecular interactions with decreasing intramolecular COO-COO distance in the diester molecule.

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Summary This work shows the result of the study of the Pb(II) and Cr(VI) ions adsorption by means of a Calvet type calorimeter of heat conduction that can operate at 150şC. The calorimeter was electrically calibrated to establish its sensitivity and reproducibility, obtaining K=12.95±0.05 W V-1 and chemically it was examined with tris-(hydroxymethyl)-aminomethane (THAM)-HCl system, obtaining ΔH= -30.91±0.03 kJ mol-1. The activated carbon sample obtained from coffee husk and the calorimetric results obtained were related to other techniques used to perform this type of studies.

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Journal of Thermal Analysis and Calorimetry
Authors:
C. Pico
,
A. Jerez
,
M. L. Veiga
, and
E. Gutierrez-Rios

The processes involved in the isothermal dehydration of hexaoxytelluric acid, Te(OH)6, are studied and the kinetic equations and activation energies corresponding to these processes are determined. The results are in agreement with a previously proposed structural model.

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Journal of Thermal Analysis and Calorimetry
Authors:
C. González
,
J. I Gutiérrez
,
J. R. González-Velasco
,
A. Cid
,
A. Arranz
, and
J. F. Arranz

Thermal decomposition of various synthetic manganese oxides (MnO, Mn3O4, Mn2O3, MnOOH) and a natural manganese dioxide (MnO2) from Gabon was studied with the help of termogravimetry in inert, oxidizing and reducing atmospheres. The compounds were characterized by XRD and electrochemical activity was tested by cyclic voltammetry using a carbon paste electrode. The natural manganese dioxide showed the best oxidizing and reducing capacity, confirmed by the lower temperatures of the transitions, the extent of the reactions and electrochemical performance in cyclic voltammograms.

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Acta Biologica Hungarica
Authors:
C. Lizette Del-Toro-Sánchez
,
S. Villaseñor-Alvarado
,
Florentina Zurita-Martínez
,
O. Castellanos-Hernández
,
Araceli Rodríguez-Sahagún
,
M. Isabel Torres-Morán
,
D. Rojas-Bravo
, and
M. Gutiérrez-Lomelí

Anemopsis californica is a perennial herbaceous plant that has been utilized as a medicinal plant for the treatment of various diseases. The present work was carried out with the objective of optimizing a method of extraction of the genomic DNA of A. californica and a PCR protocol and later to evaluate the existing genetic diversity among the genotypes deriving from different origins. For DNA extraction, we tested four procedures: with the CTA B-2 protocol, we obtained the highest yield (61.5±2.2 μg DNA/g of leaf tissues) and the best quality (A260/280 1.83±0.022). To estimate genetic variability, we utilized the randomly amplified polymorphism DNA (RAPD) technique, employing 20 oligonucleotides, of which only 18 generated reproducible banding patterns, producing 123 polymorphic bands generated, thus obtaining a polymorphism rate of 93.93% among the genotypes analyzed. The Jaccard similarity coefficient generated a variation ranging from 0.325–0.921, indicating a high level of genetic variation among the studied genotypes. An Unweighted pair-group method with arithmetic mean (UPGMA) group analysis indicated six distinct groups. The present optimized method for DNA isolation and RAPD protocol may serve as an efficient tool for further molecular studies.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. Perera
,
C. Perez
,
M. Torres
,
A. Henandez
,
F. Heres
,
T. Moreira
,
A. Gutierrez
,
A. Gigato
,
I. Hernandez
,
L. Alberti
,
O. Marrero
,
L. Martinez
,
J. Sanfiz
,
E. Sanchez
,
J. Rodriguez
,
L. Marrero
, and
G. Parra

Abstract  

The aim of this work was to obtain a freeze-dried kit for direct99mTc-labeling of human polyclonal IgG. The labeling procedure was carried out by Schwarz's method. The best yields of99mTc-IgG were obtained by using sodium pyrophosphate decahydrate as a weak chelating agent. Performed tests showed the stability of the radiopharmaceutical up to 24 hours. Plasma clearance in rats was fitted to a biexponential curve withT 1/2α=(0.1 ±0.9) h andT 1/2β=(10±3) h. The organs with higher uptake of radiopharmaceutical were lung, kidneys and blood. In a rabbit model the abscess target/background ratio was 3–6 according to time of the scintigraphic images. Thirty patients with musculoskeletal infection were studied. Twenty-one lesions were detected and confirmed by culture/biopsy.

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