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PubMedDate not supplied

[Automation of parenteral nutrition elaboration: adaptation to in force legislation].

INTRODUCTION: Quality and efficiency criteria of allowances associated to technological procedures are developing in a setting that values quality, and from there the Real Decree RD175/2001 has been issued by which the rules of correct elaboration and quality control of formulations and pharmacy preparations. Parenteral nutrition (PN) is a formulation and, as such, its elaboration and control have to agree with the in force regulations. With this aim, at the Bellvitge University Hospital we have developed a project for automation of elaboration of PN mixtures with the MicroMacro Pump 23 Baxa Compounder. OBJECTIVES: To assess the impact of implementing an automated system of volumetric control in PN elaboration. MATERIAL AND METHODS: The project development may be divided into two differentiated aspects. The first one consisted in the implementation and optimization of the automated system of volumetric control (ASVC). The second aspect comprehends the comparative control performed between the new system and the previous one, and which consisted of a gravimetric system with visual control. For that, real weights were gathered and were compared to predicted weights, and the time of elaboration per bag before and at two times after the implementation of the automated system was registered; the first time just after implementation of the system, and the second time within one year. RESULTS: For the comparison study between both systems used, 141 preparations in total, corresponding to individualized PN, were analyzed: 47 elaborated by means of the gravimetric system (GS), 47 with the ASVC during the implementation period (PN ASVC period 1), 47 PN elaborated with the ASVC within one year of implementation (PN ASVC period 2). The average variation between real weight and predicted weight at the three periods (pre-ASVC, NP ASVC period 1, NP ASVC period 2) was 2.41%, 1.35% and 1.25% respectively (table I). This decrease was statistically significant (p = 0.014). When analyzing the percentage of preparations out of the 3% variation range, we observed a significant reduction (p = 0.00001) by comparing the three periods (Table II). The average elaboration time with the ASVC increased approximately in 4 minutes by bag (3 min 58 sec) during the first studied period, and 3 min 10 sec during the second period, as compared with the study period with the GS. CONCLUSIONS: The new bag-filling system by means of volumetric control represents an improvement in accuracy control and a decrease in the risk for surpassing the acceptable limits. The implementation of a new technological procedure is a difficult task that implies the change of many aspects of the daily practice and that requires a "cultural" change in the PN Unit with the aim of optimizing the process. However, these issues allow for an adaptation to legal requisites in force regarding the regulations of proper elaboration and quality control of formulations as well as an improvement in the integral quality of care.

Automation↗
PubMedDate not supplied

Verification of a method for microcoulometric determination of adsorbable organic halide pollutants in natural, drinking, waste, and treated waters.

A microcoulometric method is described for the determination of organic-halide pollutants at 2-2000 microg/L in natural, drinking, waste, and treated waters. The conditions for the adsorption of organic halides, using a microcolumn with activated charcoal-and for the desorption of inorganic halides-as well as for the pyrolysis process, were optimized for the successful determination of priority organic halide pollutants. An appropriate criterion was proposed to stop the desorption step. The mean recovery was 100.3%, and the mean relative standard deviation was 9.9%. The detection limit based on 3 times the standard deviation of the blank sample was 2 microg/L.

Adsorption↗
PubMed2006

[Effects of absorption on photo-reduction of Cr (VI) by UV/TiO2 process and its elimination].

Reduction of Cr(VI) in aqueous solution were studied by the UV/TiO2 photo-reduction process. The results show that the photo-reduction of Cr(VI) ion by UV/TiQ2 agrees with Langmuir-Hinshelwood equation well. In absence of organic matters, absorption of TiO2 is the key step for this process, and optimal condition is pH = 1.5-2.5. The initial reduction rate correlate with pH value within pH = 1.5-10. The ability to competitively absorb to the surface of TiO2 can be ordered by PO4(3-) > SO4(2-) > Cl- > NO3-. Photoreduction rate and efficiency can be enhanced greatly with synergia of formaldehyde or formic acid, meanwhile synergia eliminate the effect of absorption. But synergic effects were reduced with phosphate.

Absorption↗
PubMed2006

[Determination of lead in water samples by graphite furnace atomic absorption spectrometry after cloud point extraction with dithizone].

Cloud point extraction was used for the preconcentration of lead after the formation of a complex with dithizone in the presence of surfactant Triton X-114, and then the lead was determined by graphite furnace atomic absorption spectrometry. The conditions affecting the separation and detection process were optimized. Separation of the two phases was accomplished by centrifugation for 15 min at 4 000 rpm. Upon cooling in an ice-bath, the surfactant-rich phase became viscous. The aqueous phase could then be separated by inverting the tubes. Later, a solution of methanol containing 0.1 mol x L(-1) of HNO3 was added to the surfactant-rich phase up to 0.5 mL. The samples were determined by graphite furnace atomic absorption spectrometry with NH4H2PO4 and Mg(NO3)2 as a chemical modifier. At pH 8.0, the preconcentration of only 10 mL sample in the presence of 0.05% Triton X-114 and 20 micromol x L(-1) dithizone permitted the detection of 0.089 microg x L(-1) lead. The enhancement factors were 19.1 times for lead. The calibration graph using the preconcentration system for lead was linear with a correlation coefficient of 0.998 from levels near the detection limits up to at least 30 microg x L(-1). The regression equation was A = 0.026 1c (microg x L(-1)) + 0.010 6. The proposed method has been applied to the determination of lead in water samples.

Dithizone↗
PubMedDate not supplied

[Biophysical aspects of reconstruction of a single cell by the methods of cell engineering].

The problems of a low efficiency of mammalian cloning are discussed with emphasis on the necessity of the expertise of each step of single cell reconstruction, beginning with microsurgical manipulations. The fact of cell content leakage when the cell is held during microsurgery or microinjections with the help of the conventional method using negative pressure in the holding micropipette was demonstrated in experiments on murine embryos. It was shown that the rate of cell content efflux depends on the value of negative pressure generated in the holding micropipette, and is directly proportional to the dimensions of its orifice and the duration of micromanipulations. An alternative method of cell fixation using the capillary forces of the holding micropipette was proposed. The method optimizes the process of cell fixation, reducing the holding effort by two orders of magnitude. As a result, 92% of embryos remain viable after fixation of embryo, as compared with 39% in the conventional technique. In order to diminish the cell damage produced by the tip of a microinstrument, a new technique of fabricating micropipettes was proposed. The improved method of filling the micropipette with viscous liquids, including DNA, which is described in details in the paper, enabled constant (non-stop) microinjection of more than 1000 cells by hand, without any special automatic device.

Animals↗
PubMed2006

[Studies on characteristics of absorption and separation of traditional Chinese medicine compound prescription by macroporous resin].

OBJECTIVE: Study the characteristics of absorption and separation of traditional Chinese medicine compound prescription using macroporous resin. METHOD: Study the techniquecs and characteristics of absorption and separation of a sample by macroporous resin, which is composed of coptis root, rhubarb and common anemarrhena rhizome, containing alkaloid, anthraquinone and saponin. RESULT: It is proved by qualitative and quantitative researches studies that after absorbed and separated by optimized technics process, most prime effective components or section fractions in traditional Chinese medicine compound prescription can be reserved maintained. CONCLUSION: If the techniquecs of separation is properly designed, the same kind of macropore resin can absorbd and separate various effective components or section in traditional Chinese medicine compound prescription which have with different chemical structures efficiently.

Alkaloids↗
PubMedDate not supplied

[The stress response in the yeast Saccharomyces cerevisiae].

All living organisms are subject to changing environmental conditions, to which they must adapt in order to survive. Recently, there have been significant advances leading to the comprehension of the different mechanisms implicated in the responses to stressful situations in the yeast S. cerevisiae. In nature, as well as in laboratory conditions or industrial processes, this yeast is subjected to different adverse environmental situations, such as osmotic, thermal and oxidative stresses. A general stress response pathway, mediated by protein kinase A, allows S. cerevisiae to cope with these three stressful conditions. However, there are also specific response pathways that include the HOG kinase for osmotic stress, the Heat Shock Factor for thermal stress and Yap1p and Yap2p transcription factors that regulate the oxidative stress response, among other enzymatic and non-enzymatic mechanisms. In this review, we describe the perception and signal transduction pathways that regulate gene expression leading to the adaptation to most common types of stress in S. cerevisiae. We also include information regarding the interaction between the signal transduction pathways involved in the different responses that allow this organism to coordinate its various physiological processes for optimal adaptation to the changing environment.

Cyclic AMP↗
PubMed1990

Modeling, adaptive control, and optimal drug therapy.

Drug therapy, its clearly development, and the advent of pharmacokinetic models are described, from the original work of Teorell, through that of Augsberger and Kruger-Thiemer, to the present. Adaptive control of such models, long known in engineering, began in therapeutics with methods for linear and nonlinear least-squares regression, and has progressed to the Maximum Aposteriori Probability (MAP) Bayesian method. Strategies for optimal monitoring of serum concentrations are described and their clinical results briefly evaluated. Lastly, the new method of Approximate Optimal Closed-Loop (AOCL) control is described, in which the therapeutic regimen is used at the same time to probe (learn about) the patient's model approximately optimally. The new method considers the expected values of planned future serum concentrations (or other responses), in addition to the traditional measurement of past serum concentrations. This should optimize the process of learning about a patient's model while treating him at the same time.

Bayes Theorem↗
PubMed1990

[Various principles of the formation of toxic gaseous pesticide degradation products in the soil].

The intensity of gaseous products of pesticides degradation in soil depends on the natural and antropogenic factors: type of soil, hydrothermal conditions, dose of the pesticide, presence in soil of other agrochemicals which can inhibit and also potentiate this process. The optimal conditions for the formation of volatile products of decay of chlororganic pesticides are created in dark chestnut and gray soils, derivatives of carbamine acids--in dark grey soil at humidity of 60-80% from the complete moisture capacity. Mineral fertilizers--ammoniacal nitrate and ammoniacal water, herbicides ronite and betanol--potentiate the decay of chlororganic pesticides, which can be used in the development of measures on soil purification from persistent pesticides.

Air Pollutants↗
PubMedDate not supplied

[A universal slide with a chemically resistant coating for microbiological studies].

The aim of this investigation was to work out the design and technology for the universal slide plate with the chemical resistant coating, which allows to grind in the covering glass and create on that basis the set of hermetic micro-cuvettes for different types of microbiological investigations. Different methods of coating manufacture and the results of the tests in working reagents were considered. The optimal technological process was chosen.

Corrosion↗
PubMedDate not supplied

[Various features of peroxidase in human saliva].

Optimal conditions are determined for isolation and purification of peroxidase (EC 1.11.1.7) from the mixed human saliva by gel-filtration and ion chromatography. Such properties as pH and temperature optima, molecular weight, Km, amino acid composition, the effect of activators and inhibitors (purified saliva peroxidases and commercial preparation of horse-radish peroxidase "Reanal", Hungary) are studied with the use of different substrates. The data obtained are necessary to optimize production processes of isolation, storage and methods of the experimental and clinical application of peroxidases of different origin.

Amino Acids↗
PubMed1989

Computer-assisted shared care: the Aberdeen Blood Pressure Clinic.

A computer-assisted shared-care follow-up system, the patient record system, was used to follow up more than 3300 patients referred for assessment of hypertension. The patients are being followed up in collaboration with more than 250 general practitioners either in the hospital or in general practice, according to the assessment at each visit. The follow-up incorporates measures to control blood pressure below arbitrary target levels. Clinically important information is shared between doctors and between doctors and patients in order to highlight patients at risk, poor control of blood pressure, drug-host and drug-drug interactions and adverse reactions and to optimize the process and outcome of care.

Ambulatory Care Information Systems↗
PubMedDate not supplied

[Effect of 8-Br-cAMP on the formation of conditioned reflex behavior in the white rat].

The influence of cAMP analogue 8-Br-cAMP on conditioning was studied in white rats. Two models of learning were used with different kinds of reinforcement, i. e. conditioned active avoidance and instrumental alimentary reactions in a complex maze. Intraventricular 8-Br-cAMP injection 4 or 24 hours before the beginning of learning improved the process of defensive as well as alimentary conditioning. Characteristics of formation of complex behaviour of experimental rats in a maze showed that under the influence of 8-Br-cAMP, not only conditioning was accelerated, but the process of optimal decision making itself was changed. The data obtained permit to suppose that 8-Br-cAMP first of all affects initially poorly learning rats.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1985

The voltage-sensitive Na+/H+ exchange in sea urchin spermatozoa flagellar membrane vesicles studied with an entrapped pH probe.

Flagellar plasma membrane vesicles were isolated from sea urchin sperm using osmotic lysis. A membrane impermeant fluorescence pH indicator, pyranine, was incorporated into the vesicles as they resealed after lysis and was used to measure the intravesicular pH (pHi). Addition of Na+ rapidly alkalinized the pHi of vesicles prepared with an internal acidic pH gradient. The pHi increase showed ionic selectivity in the order of Na+ greater than Li+ much greater than K+ approximately equal to Cs+ approximately equal to O. Complete removal of monovalent anions such as Cl- and HCO3- did not affect the exchange, thus ruling out the participation of an anion carrier in the process. The optimal operation of the exchanger, however, required the presence of a transmembrane potential, which could be generated by the diffusion potential of either K+, a naturally permeant ion, or Cs+ which was artificially made permeant by the ionophore valinomycin. Depolarization inhibited the exchange in both the forward and the reverse directions, which is consistent with the voltage-gated electroneutral exchange mechanism proposed previously for this exchanger (Lee, H. C. J. Biol. Chem. (1984) 259, 15315-15319). The voltage sensitivity of the Na+/H+ exchanger was found to be modulated by the presence of Mg2+. A model involving the screening of the internal surface potential was proposed to account for the Mg2+ effect. The vesicle preparation used in this study allows complete control of the internal contents and represents a major simplification of the system as compared with the intact sperm and the isolated flagella used previously.

Animals↗
PubMedDate not supplied

[Creation of a polyenzyme composition of proteases from Streptomyces griseus and Acremonium chrysogenum].

Proteolytic enzymes of microorganisms have been studied for the possibility to create their polyenzymic composition in order to rise a degree of protein hydrolysis and to lower the process duration. Optimal action conditions are selected and a hydrolysis of a number of globular and fibrillar proteins is conducted by a polyenzymic system of Streptomyces griseus and Acremonium chrysogenum proteases.

Acremonium↗
PubMed1987

Development of a hepatitis B vaccine from transformed yeast cells.

The production in yeast cells of the recombinant DNA hepatitis B vaccine of SmithKline Biologicals involves an optimized fermentation process followed by cell disruption and extraction, together with other soluble yeast components of the surface antigen of the hepatitis B virus. The subsequent purification process includes precipitation steps, ion exchange and gel permeation chromatography, and caesium chloride ultracentrifugation. The yeast-derived antigen occurs as spherical particles containing the non-glycosylated HBsAg polypeptide, lipid, and Tween 20. The purity of the polypeptide is above 95% and confirmed by the absence of an immune response to yeast-derived contaminants in vaccinees. Yeast DNA levels were less than 10 pg/vaccine dose. Various biochemical analyses showed that the recombinant polypeptide was faithfully expressed and did not undergo unwanted processing or degradation during fermentation or purification. These results indicate that the recombinant HBsAg can be effectively produced in yeast and processed to a high degree of purity to yield HBsAg particles displaying most of the characteristic properties of plasma-derived HBsAg.

Amino Acid Sequence↗
PubMed1987

[Distributed automatic control system for experiments on the cultivation of microorganisms].

Hard- and software of a distributed system for computer control of experiments on cultivation of microorganisms is described. The system is based on microprocessor techniques and minicomputer CM-4(1420). It provides intensification of microbiological studies due to rational management of experiments, accumulation and long-term storage of experimental data and their processing with specific algorithms for providing additional information on biosynthetic processes and optimization of fermentation conditions.

Analog-Digital Conversion↗