Frailty, Falls and Osteoporosis: Learning in Elderly Patients Using a Theatrical Performance in the Classroom.

OBJECTIVE: To ascertain the usefulness of a simulated clinical scene with actors in the classroom (theatrical performance) as a teaching tool for the management of falls and their related injuries. DESIGN: Experimental design of two related groups. SETTING: Spain. PARTICIPANTS: A group of 12 students attended a seminar in which the approach to a clinical case was made using a simulated scene with actors in the classroom (scene group); a non-scene group of 34 students attended the seminar, without a theatrical performance (the same clinical case was read and presented in a traditional manner, oral presentation). MEASUREMENTS: Before and after the seminar, students answered a questionnaire [five questions on theoretical knowledge of falls and osteoporosis (score 0-10) and two on subjective learning perception (linear scale: 0-10) (score 0-20)]. In the scene group were two further questions included at the end on their opinion of the scene and on the seminar overall. RESULTS: Both groups significantly improved in all questionnaire scores after the seminar (p=0.001). The scene group had a greater rise in mean points of the questionnaire before and after the seminar than the non-scene group: theoretical knowledge [3.81±1.69 versus 2.75±1.33 (p=0.033)], subjective questions [6.08±4.10 versus 4.97±2.24 (p=0.247)], and the questionnaire overall [9.89±4.98 versus 7.72±2.66 (p=0.060)]. The scene group had a very good opinion of the usefulness of the scene and of the overall opinion of the seminar: 9.08±0.95 and 9.41±0.79. CONCLUSIONS: Theatrical performance in the classroom seems to promote better learning than classic oral presentation, providing qualitative value by adding creativity and different approaches to the teaching of medicine.

Vitamin B12 deficiency and clinical laboratory: Lessons revisited and clarified in seven questions.

The objective of this review article is to address the most frequently asked questions that pathologists and primary care physicians might face when dealing with a patient with suspicion of vitamin B12 deficiency. More specifically, the article mainly discusses the importance and prevalence of the deficit, how to recognize it, and the important role of a prompt diagnosis confirmation based on laboratory biomarkers for efficient replacement therapy.

[Quality assessment for preanalytical phase in clinical laboratory: a multicentric study]. / Evaluación de la calidad en el laboratorio en la fase preanalítica: un estudio multicéntrico.

PURPOSE: To show the number of preanalytical sample errors in seven laboratories attending seven health departments of Valencian Community (Spain). METHODS: Cross-sectional study of the number of preanlytical errors in samples obtained in primary care centers. An error is defined as a rejected specimen: any blood or urine sample, which cannot be successfully tested as it does not meet the acceptability criteria of the laboratory or if the sample is not received. We collected preanalytical errors from the tests requested for hematology, coagulation, chemistry, and urine samples. Registers were collected and indicators calculated automatically through a data warehouse and OLAP cubes software. RESULTS: Large differences in the results of preanalytical errors were observed between health departments. The highest percentage of errors occurred in coagulation samples, followed by urine, hematology and biochemistry. With regard to the type of error, the largest proportion of errors was due to failures of process. CONCLUSIONS: The high incidence of preanalytical errors and variability between health departments suggests that there is a need to standardize the drawing practice.

[Regional pilot study to evaluate the laboratory turnaround time according to the client source]. / Estudio piloto regional de evaluación del tiempo de respuesta de laboratorio según el tipo de cliente.

PURPOSE: To show turnaround time to client source in eight laboratories covering eight Health Areas (2,014,475 inhabitants) of the Valencian Community (Spain). MATERIAL AND METHODS: Internal Laboratory Information System (LIS) registers (test register and verification date and time), and daily LIS registers were used to design the indicators, These indicators showed the percentage of key tests requested (full blood count and serum glucose and thyrotropin) that were validated on the same day the blood was taken (inpatients and Primary Care and/or at 12 a.m. (inpatients). Urgent (stat) tests were also registered as key tests (serum troponin and potassium) and were recorded in minutes. Registers were collected and indicators calculated automatically through a Data Warehouse application and OLAP cube software. RESULTS: Long turnaround time differences were observed at 12 a.m. in inpatients, and in the day of sample extraction in primary care patients. The variability in turnaround of stat tests is related to hospital size, activity and validation by the laboratory physician. CONCLUSIONS: The study results show the large turnaround time disparity in eight Health Care Areas of Valencian Community. The various requesting sources covered by the laboratories create the need for continuous mapping processes redesign and benchmarking studies to achieve customer satisfaction.

Migration analysis of epoxidized soybean oil and other plasticizers in commercial lids for food packaging by gas chromatography-mass spectrometry.

A modification of the method of Castle et al. (J. Chromatogr. 1988: 437:274-280) for the analysis of epoxidized soybean oil (ESBO) is proposed to simplify the analysis and reduce the time and consumption of reagents. The proposed modifications, particularly the elimination of the internal standard, resulted in a simpler, faster and more economical method. A complete analytical validation, including evaluation of the main analytical parameters, such as detection and quantification limits, linearity, working range, precision, accuracy and selectivity, was carried out. The data demonstrated the suitability of the proposed method for the determination of ESBO in polymer matrices. A specific migration study for ESBO in different food simulants (fat and aqueous) was carried out by applying the method to poly(vinyl chloride) materials prepared with known amounts of ESBO, as well as some commercial lids. High levels of migration of ESBO into fat simulants were found. In the case of commercial lids, in addition to ESBO, some other plasticizers such as citrates, adipates and sebacates were found and quantified to establish their migration under different conditions of use.

Role of the yeast ABC transporter Yor1p in cadmium detoxification.

Growth of yeast strains, either deleted for the vacuolar ABC transporter Ycf1 or deleted for the plasma membrane ABC transporter Yor1p or overexpressing Yor1p, were compared for their sensitivity to cadmium. On solid medium cell death (or growth inhibition) was observed at cadmium concentrations higher than 100 microM when yeasts were grown at 30 degrees C for 24 h. However, for all tested strains cell death (or growth inhibition) was already observed at 40 microM cadmium when incubated at 23 degrees C for 60 h. Thus cadmium is more toxic to yeast at 23 degrees C than at 30 degrees C. At 23 degrees C, the Deltayor1 strain grew more slowly than the wild-type strain and the double Deltayor1, Deltaycf1 deleted strain was much more sensitive to cadmium than each single Deltayor1 or Deltaycf1 deletant. Overexpression of Yor1p in a Deltaycf1 strain restores full growth. Cadmium uptake measurements show that Deltaycf1 yeast strains expressing or overexpressing Yor1p store less cadmium than the corresponding Deltaycf1, Deltayor1 strain. The strains expressing Yor1p display an energy-dependent efflux of cadmium estimated for the yeast overexpressing Yor1p to be about 0.02 nmol 109Cd/mg protein/min. Yeast cells loaded with radiolabeled glutathione and then with radioactive cadmium displayed a twice-higher efflux of glutathione than that of cadmium suggesting that Yor1p transports both compounds as a bis-glutathionato-cadmium complex. All together, these results suggest that in addition to being accumulated in the yeast vacuole by Ycf1p, cadmium is also effluxed out of the cell by Yor1p.

Determination of residual styrene monomer in polystyrene granules by gas chromatography-mass spectrometry.

Polystyrene is widely used in formulations intended for children use. The main problem with this plastic is the residual styrene, which can migrate from the product, and therefore, be in contact with children. The acute toxicity of styrene is well known, raising the need of an efficient and fast method of analysis for this compound. Several extraction methods have been evaluated and compared for the determination of residual styrene monomer in polystyrene granules used in toys: supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), Soxhlet extraction, headspace emission and dissolution-precipitation. The analyte was subsequently detected by gas chromatography (GC) with MS detection. The results indicated that the most efficient method was dissolution-precipitation giving even higher extraction efficiency than SFE. For validating the method, PS samples spiked with known quantities of styrene at three concentration levels were prepared to calculate the extraction recovery. The founded validation data proved the suitability of the proposed method.

Determination of N-nitrosamines in latex by sequential supercritical fluid extraction and derivatization.

A new method to determine N-nitrosamines in latex products has been developed by combination of supercritical fluids and chemical derivatization. A new design for a liquid trap has been introduced. A factorial fractional design was used in order to evaluate the influence of the different factors affecting the process. Factors such as pressure, temperature, static and dynamic time, restrictor temperature and volume of an hydrobromic acid-acetic anhydride mixture (1:10, v/v) were included in the design. CO2 was used as the extraction fluid. Gas chromatography with nitrogen and phosphorus sensitive detection was employed to achieve good sensitivity attending to the molecular structure of these compounds (N-nitrosamines and their corresponding secondary amines). The obtained results have shown to be useful to increase selectivity and reduce sample handling.

Determination of aromatic amines formed from azo colorants in toy products.

A study for the determination of the aromatic amines formed after reduction of the azo colorants mostly used in toys was conducted. Sodium dithionite was used in the reductive cleavage of the azo group for the dyes, and the released amines were subsequently analysed by high-performance liquid chromatography with UV detection. The influence of different variables related to the reduction process was investigated by the use of a full-level factorial design, where most significant parameters as well as order interactions were studied. Reduction profiles for each colorant were obtained by studying the changes in the amount of amine obtained with different dithionite/colorant ratios. The expected aromatic amines forming azo colorants were detected, and in the presence of a nitro group a further reduction was observed. The yield of the total reduction process was determined by using standard addition of different quantities of amines to the colorants.

Optimization of parameters for the supercritical fluid extraction in the determination of N-nitrosamines in rubbers.

The study of the possibilities of supercritical fluid extraction (SFE) with N-nitrosamines in rubbers has been carried out. Home-made materials fortified with several N-nitrosamines were prepared in order to optimize the SFE parameters. A Plackett-Burman design was employed to evaluate the influence of those parameters to be controlled in SFE, such as pressure, temperature, static and dynamic time, restrictor temperature and volume of modifier while CO2 was used as the extraction fluid. An extra central composite design for the main factors (according to the previously obtained results) was also developed in order to refine the best supercritical conditions for the extraction of N-nitrosamines from rubbers. Gas chromatography with a nitrogen and phosphorus sensitive detector was used to achieve sensitivity and limits of detection for the concentrations expected in plastic materials. The proposed analytical method has shown to be useful in the determination of N-nitrosamines even for complex matrices.

Optimization of the extraction of azo colorants used in toy products.

Azo dyes are widely used in formulations intended for children use. But their potential toxicity raised the need of an efficient and fast method of analysis. A study for the optimization of the extraction of some azo colorants used in toys was conducted. Several extraction methods for the selected analytes were evaluated and compared, i.e., supercritical fluid extraction (SFE), microwave-assisted extraction (MAE) and Soxhlet extraction. Poly(vinyl chloride) samples spiked with known quantities of the studied dyes were prepared. The influence of critical variables on analyte recoveries in SFE and MAE was investigated by using a full-level factorial design, where most significant parameters as well as order interactions were studied in each case. The analytes were subsequently detected by high-performance liquid chromatography with UV detection. The three extraction techniques were compared in terms of reproducibility, selectivity and analyte recoveries. MAE showed higher recoveries (above 98%), except for the diazo dye (nearly 60%). Reproducibilities were generally good for the three methods (relative standard deviation lower than 2.0%).

Simultaneous supercritical fluid derivatization and extraction of formaldehyde by the Hantzsch reaction.

A study where the Hantzsch reaction is used to produce the chemical derivatization of formaldehyde in a supercritical medium is presented in this paper. Pressure, temperature and other parameters such as static and dynamic extraction time must be optimized to increase the yield of this kinetically controlled reaction. A 2(5-1) (resolution V) factorial design was used to study the significant parameters affecting the supercritical process in terms of resolution and sensitivity. A subsequent central composite design was employed to find the conditions of maximum response. Ultraviolet-visible spectrophotometry was used as the detection technique. The optimum conditions were used for the determination of formaldehyde in real finger-paints by means of the previous addition of known quantities of this analyte to the paint. Results were compared with those obtained with supercritical fluid extraction and subsequent chemical derivatization and an improvement of sensitivity as well as a reduction of time of analysis, solvent waste and reagents consumption were observed.

Optimization of parameters for the analysis of aromatic amines in finger-paints.

A study for the optimisation of the supercritical fluid extraction (SFE) of some aromatic amines (4-chloro-o-toluidine, 2-naphthylamine, 4-aminobiphenyl and benzidine) in finger-paints was conducted. The influence of different variables related to the technique on recoveries was investigated. The analytes were subsequently analysed by gas chromatography after SFE. The study allowed the estimation of four main factors (temperature, pressure, static time and volume of modifier) on recoveries by the use of a two-level factor design, where most significant parameters as well as second- and third-order interactions were identified. Other factors, such as type and volume of modifier and time of contact between the spiker solution and the sample prior to extraction, were also studied. The influence of matrix on extraction recovery was also evaluated by applying the method to different finger-paints, and recoveries were similar or even higher in some cases. The drying process of samples was also studied, while classical drying in an oven and microwaves were compared, with similar efficiencies in both methods. The method was validated by extracting the aromatic amines from some commercial finger-paints.

Multiple recognition of various amphiphilic molecules by the multidrug resistance P-glycoprotein: molecular mechanisms and pharmacological consequences coming from functional interactions between various drugs.

P-glycoprotein (P-gp) is an active, ATP-dependent plasma membrane transporter which is responsible for the expulsion of various cytotoxic drugs with different chemical structures out of resistant (MDR) cells. It is also capable of transporting a number of other amphiphilic molecules, the so-called MDR-reversing agents, which belong to a very broad variety of chemical families. Moreover, P-gp can also play a role in steroid secretion and cellular detoxification by transporting various other substrates. In this review, we address the problem of the multiple recognition by P-gp of such a large number of amphiphilic molecules. This is both (i) from a basic viewpoint in order to discuss the underlying molecular mechanisms explaining how the general rule of substrate-enzyme specificity can be violated, and (ii) from a more applied pharmacological viewpoint to show in detail how the interaction of various drugs with P-gp leads to important consequences in terms of the relative effects of these drugs in the anticancer chemotherapy context, as well as for their pharmacokinetic distributions in the whole organism, rationalizing possible adverse drug reactions. In particular, we will present evidence that, independently of the technique used, the mutual interactions between P-gp transport substrates cannot always be reduced to simple competitive effects.

Determination of some aromatic amines in finger-paints for children's use by supercritical fluid extraction combined with gas chromatography.

A test method based on supercritical fluid extraction (SFE) and gas chromatography has been developed for some aromatic amines, such as 4-chloro-o-toluidine, beta-naphthylamine and 4-aminobiphenyl. A two-level factor design was used as the optimization procedure. Four main variables were considered: CO2 pressure, extraction temperature, static extraction time and volume of modifier (methanol). Results obtained for 4-chloro-o-toluidine, indicated that the volume of modifier was the variable with the most important influence on extraction, CO2 pressure had a negative effect and temperature and time were less significant. For the other amines, static time was the most important variable in both cases, followed by CO2 pressure and volume of modifier, with no influence of temperature. SFE was compared with Soxhlet extraction, and was found to give higher recoveries in all cases. Other commercial finger-paints were tested for the presence of aromatic amines.