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OBJECTIVE: The aim of our study was to determine the self-reported prevalence of use of emergency contraception (EC), identify factors associated with EC use, and measure the prevalence in university students of pregnancy and abortion among users and non-users of EC. METHODS: A cross-sectional descriptive study of university students using a self-administered questionnaire was carried out in 2016. The main dependent variable was EC use at any time. Independent variables included sociodemographic factors and factors related to harmful habits and sexual behaviour. RESULTS: The study sample consisted of 1309 students (median age 20 years). Forty per cent of participants reported using EC; condom failure was given as the main reason. Variables associated with EC use in both men and women were illegal drug consumption and having had more than 10 sexual partners. In women, other factors associated with EC use were age at first coitus and non-centrist political views. The prevalence of pregnancy was 6.5% and the prevalence of voluntary abortion was 2.9%. This prevalence was similar for men and women and for EC users and non-users. CONCLUSION: EC use in university students was more likely in those who experienced contraceptive failure or used no contraception. There were differences between men and women. Those at higher risk of unplanned pregnancy were more likely to report EC use, which may explain why there was no difference in the rates of unwanted pregnancies between EC users and non-users.

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Multiphase and droplet microfluidic systems are growing in relevance in bioanalytical-related fields, especially due to the increased sensitivity, faster reaction times and lower sample/reagent consumption of many of its derived bioassays. Often applied to homogeneous (liquid/liquid) reactions, innovative strategies for the implementation of heterogeneous (typically solid/liquid) processes have recently been proposed. These involve, for example, the extraction and purification of target analytes from complex matrices or the implementation of multi-step protocols requiring efficient washing steps. To achieve this, solid supports such as functionalized particles (micro or nanometric) presenting different physical properties (e.g. magnetic, optical or others) are used for the binding of specific entities. The manipulation of such supports with different microfluidic principles has both led to the miniaturization of existing biomedical protocols and the development of completely new strategies for diagnostics and research. In this review, multiphase and droplet-based microfluidic systems using solid suspensions are presented and discussed with a particular focus on: i) working principles and technological developments of the manipulation strategies and ii) applications, critically discussing the level of maturity of these systems, which can range from initial proofs of concept to real clinical validations.

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The sealing of microfluidic devices remains a complex and time-consuming process requiring specific equipment and protocols: a universal method is thus highly desirable. We propose here the use of a commercially available sealing tape as a robust, versatile, reversible solution, compatible with cell and molecular biology protocols, and requiring only the application of manually achievable pressures. The performance of the seal was tested with regards to the most commonly used chip materials. For most materials, the bonding resisted 5 bars at room temperature and 1 bar at 95 °C. This method should find numerous uses, ranging from fast prototyping in the laboratory to implementation in low technology environments or industrial production.

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Nowadays there is a short-term need of investigating in orthopedic implants with a greater functionality, including an improved osseointegration and also antibacterial properties. The coating of metallic implants with hydroxyapatite (HA) remains to be the main proposal, but superior quality HA coatings with compositions closer to natural bone apatites, including carbonates, trace elements are required. Selenium is an essential nutrient in biological tissues and, at the same time, it also presents antibacterial properties. A pioneering study on the fabrication of selenium-doped carbonated hydroxyapatite (iHA:Se) coatings by Pulsed Laser Deposition (PLD) is presented. Different proportions of selenium were incorporated to obtain the iHA:Se coatings. Their physicochemical characterization, performed by SEM/EDS, FTIR, FT-Raman, Interferometric Profilometry and XPS, revealed typical columnar growth of HA in globular aggregates and the efficient incorporation of selenium into the HA coatings by the, most probably, substitution of SeO(3)(2-) groups in the CO(3)(2-) sites. Biological evaluation illustrated the absence of cytotoxicity when an amount of 0.6 at.% of Se was added to the iHA:Se coatings and excellent proliferation of the MC3T3-E1 preosteoblasts. Antibacterial properties were also proved with the inhibition of P. aeruginosa and S. aureus from establishing bacterial biofilms.

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Carbon scaffolds with a directional patterned surface were obtained by pyrolysis of the sea rush Juncus maritimus. The structure of the scaffolds was investigated using scanning electron microscopy, mercury porosimetry and interferometric profilometry. X-ray diffraction and x-ray fluorescence were the techniques used for their chemical characterization. The alignment and differentiation of pre-osteoblasts (MC3T3-E1 cell line) incubated on the patterned scaffolds were evaluated by scanning electron microscopy, confocal laser scanning microscopy and by the quantification of the phosphatase alkaline activity and the osteocalcin synthesis. It was found that pyrolysis at 500 °C preserved and even enhanced the natural macro- and micro-patterning of the plant. The results obtained for porosity and chemical composition validated these structures as viable scaffolds for tissue engineering applications. Finally, the patterned surface was confirmed to promote the oriented growth of the pre-osteoblasts MC3T3-E1, not only after short periods of incubation (hours) but also after longer ones (several weeks). The quantification of the cell differentiation markers together with the evaluation of the cell layer morphology up to 28 days of incubation confirmed the differentiation of MC3T3-E1 cells to osteoblasts.

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La gran mayoría de niños expuestos al tabaco no eligen esta exposición. Se estima que alrededor de la mitad de los niños se encuentran en un ambiente contaminado por el humo del tabaco, particularmente en su domicilio. Los resultados obtenidos en los estudios sobre tabaco y enfermedad invasora por Haemophilus influenzae tipo B y Streptococcus pneumoniae no son consistentes; se precisan nuevas investigaciones que aporten mayor evidencia con respecto a esta posible asociación, ya que determinados hallazgos biológicos apuntan hacia ella. La exposición al tabaco en los niños aumenta el riesgo de padecer enfermedad invasora por meningococo; así lo confirman varios estudios en los que existe una importante fuerza de asociación después de haber ajustado por posibles variables de confusión. Estos hallazgos aumentan la evidencia del efecto perjudicial del tabaco en la salud infantil. Toda estrategia encaminada a la reducción de esta exposición contribuirá a mejorar la salud infantil; en este sentido, hay que hacer hincapié en la conveniencia de no fumar en presencia del niño y, fundamentalmente, en el domicilio

The great majority of children who are exposed to tobacco smoke do not choose this exposure. It is estimated that about half of all children are subjected to environments contaminated by tobacco smoke, mainly at home. The results of studies of the association between exposure to tobacco smoke and risk for invasive Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae are not consistent and further studies providing greater evidence of a relationship will be necessary since there are certain biological findings that suggest that it exists. Exposure to tobacco smoke increases the risk of invasive meningococcal disease in children, as has been shown in a number of studies that have demonstrated a strong association after adjustment for different confounding variables. These findings increase the body of evidence of the harmful effect of tobacco smoke on children's health. Any strategy aimed at reducing the exposure of children to tobacco smoke will improve their health. It is important to educate parents and the importance of avoiding smoking in the household should be stressed

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A one-step extraction-purification method for the determination of polychlorinated biphenyls (CBs) in fat samples was developed. Matrix solid-phase dispersion using different combinations of normal phase sorbents and elution solvents was evaluated, in terms of extraction yield and lipids removal efficiency, for the isolation of CBs from butter, chicken and beef fat. Under optimal conditions, 0.5 g of sample was dried with anhydrous sodium sulphate, dispersed on 1.5 g of Florisil and transferred to the top of a polyethylene solid-phase extraction cartridge which already contain 5 g of Florisil. Non-coplanar CBs were quantitatively eluted with 15 ml of n-hexane. The lipid percentage in this extract remained below 0.06% of the sample mass. As coplanar congeners show a higher affinity for Florisil, 20 ml of hexane-dichloromethane (90:10) were necessary for the quantitative recovery of coplanar and non-coplanar CBs. The potential of the procedure to fractionate non-coplanar and coplanar congeners is discussed. After extract evaporation to 0.2 ml, quantification limits of 0.4 ng of each CB per g of fat were achieved, using gas chromatography with tandem MS or electron-capture detection (ECD).

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A procedure for the determination of the total content of polychlorinated biphenyls (PCBs) in industrial oil samples using gas chromatography coupled to atomic emission detection (GC-AED) is presented. Analytes were extracted from the samples using dimethylsulfoxide (DMSO), this extract was diluted with water, and PCBs were concentrated on a PDMS-DVB solid-phase microextraction (SPME) fibre using the headspace (HS) mode. Fibres were thermally desorbed for 3 min in the splitless injection port of the GC-AED system. Influence of liquid-liquid extraction conditions on the performance of the analytical procedure is presented and the need of a sample oxidation step, previous to the extraction of the PCBs with DMSO, discussed. Working under optimal conditions, quantification limits from 0.5 to 1 microg/g (total PCBs content) were obtained for several Aroclor mixtures in transformer oil samples. The repeatability of the whole sample preparation procedure (liquid-liquid partition followed by headspace SPME and GC-AED determination) ranged from 4 to 7%.

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BACKGROUND: Urinary tract infection (UTI) is a common health care problem. Recurrent UTI (RUTI) in healthy non-pregnant women is defined as three or more episodes of UTI during a twelve month period. Long-term antibiotics have been proposed as a prevention strategy for RUTI. OBJECTIVES: To determine the efficacy (during and after) and safety of prophylactic antibiotics used to prevent uncomplicated RUTI in adult non-pregnant women. SEARCH STRATEGY: We searched MEDLINE (1966-April 2004), EMBASE (1980-January 2003), Cochrane Central Register of Controlled Trials( in The Cochrane Library Issue 1, 2004) and reference lists of retrieved articles SELECTION CRITERIA: Any published randomised controlled trial where antibiotics were used as prophylactic therapy in RUTI. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. Statistical analyses were performed using the random effects model and the results expressed as relative risk (RR) with 95% confidence intervals (CI). MAIN RESULTS: Nineteen studies involving 1120 women were eligible for inclusion. Antibiotic versus antibiotic (10 trials, 430 women): During active prophylaxis the rate range of microbiological recurrence patient-year (MRPY) was 0 to 0.9 person-year in the antibiotic group against 0.8 to 3.6 with placebo. The RR of having one microbiological recurrence (MR) was 0.21 (95% CI 0.13 to 0.34), favouring antibiotic and the NNT was 1.85. For clinical recurrences (CRPY) the RR was 0.15 (95% CI 0.08 to 0.28). The NNT was 1.85. The RR of having one MR after prophylaxis was 0.82 (95% CI 0.44 to 1.53). The RR for severe side effects was 1.58 (95% CI 0.47 to 5.28) and for other side effects the RR was 1.78 (CI 1.06 to 3.00) favouring placebo. Side effects included vaginal and oral candidiasis and gastrointestinal symptoms. Antibiotic versus antibiotic (eight trials, 513 women): These trials were not pooled. Weekly pefloxacin was more effective than monthly. The RR for MR was 0.31(95% CI 0.19 to 0.52). There was no significant difference in MR between continuous daily and postcoital ciprofloxacin. REVIEWERS' CONCLUSIONS: Continuous antibiotic prophylaxis for 6-12 months reduced the rate of UTI during prophylaxis when compared to placebo. After prophylaxis two studies showed nodifference between groups. There were more adverse events in the antibiotic group. One RCT compared postcoital versus continuous daily ciprofloxacin and found no significant difference in rates of UTIs, suggesting that postcoital treatment could be offered to woman who have UTI associated with sexual intercourse.

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A procedure for the determination of 17 chlorophenolic compounds in ash samples obtained from the incineration of waste materials is described. Analytes were simultaneously derivatized with acetic anhydride in presence of triethylamine (TEA), and extracted from the sample in a mixture of n-hexane acetone using a microwave system equipped with closed extraction vessels. Influence of five experimental parameters (volume of TEA and acetic anhydride, extraction time and temperature, as well as the volume of n-hexane acetone) on the yield of the derivatization-extraction procedure was systematically studied using a uniform experimental design at four levels, followed by a conventional factorial design at two levels. Under optimal extraction conditions, recoveries from 72 to 94% were obtained for a spiked ash sample with a carbon content of 8.7%. Quantification limits of the proposed procedure ranged from 2 to 5 ng/g using GC-MS as detection technique. The proposed method was applied to the determination of chlorophenols in three ash samples obtained from different incineration plants. Total chlorophenol contents of 423 and 135 ng/g were found in two of these samples.

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A procedure for the determination of several coplanar and non coplanar PCBs in ash samples is described. Analytes were extracted from the samples using dimethylsulfoxide (DMSO) under the action of a microwave field, and then they were concentrated on a PDMS-DVB solid-phase microextraction (SPME) fibre using the headspace mode, after water dilution of the DMSO extract. Determinations were carried out using GC-ECD and GC-MS detection. Influences of microwave extraction (solvent volume, temperature and time) and SPME conditions (stirring, kind of SPME fibre, salt and water addition, sampling time and temperature) on the performance of the whole analytical procedure were systematically investigated. Working under optimal conditions quantification limits from 0.2 to 1.5ngg(-1) were obtained for all the compounds, except for PCB 209, which could not be consistently extracted from the sample using the proposed conditions.

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An alternative method for the extraction of polychlorinated biphenyls (PCBs) in ash samples, which is less time and solvent consuming than Soxhlet extraction, is presented. A study was carried out to evaluate the possibilities of microwave-assisted extraction (MAE) to determine exactly which parameters affect the efficiency of the process, since direct extrapolation of extraction conditions for PCBs in other solid matrices, failed when applied to coplanar congeners in ash samples. Influence of the organic solvent on the yield of the extraction was first evaluated using two ash samples with different percentages of carbon. Once the extraction solvent was fixed, the effects of solvent volume, extraction temperature and extraction time were investigated using an experimental design. It was found that the volume of organic solvent played a more important role in the extraction efficiency than the other factors. In the optimal conditions microwave extractions were performed at 110 degrees C. for 10 min and using 30 ml of toluene. Recoveries higher than 80% were obtained for all the highly chlorinated congeners. including coplanar species, in a spiked ash sample containing a relatively high concentration of carbon. The proposed method was also applied to the determination of PCBs in a reference material of urban dust. Recoveries were similar to those obtained for spiked ash samples.

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BACKGROUND: Streptococcus pneumoniae is a significant cause of meningitis and septicemia in early infancy, being associated to a high case-fatality rates and serious sequelae. OBJECTIVE: To investigate the burden of invasive disease caused by S. pneumoniae in Valencia, Spain, during a three-year period (1996-1998). METHODS: Hospital-based prospective active surveillance program for invasive bacterial diseases in children < or = 15 years of age in Valencia, from December 1, 1995 to January 1999. RESULTS: A total of 94 cases of invasive pneumococcal disease were detected in patients < or = 15 years of age. The overall annual incidence of invasive pneumococcal disease was 4.6/100,000 persons, < or = 15 years of age. The incidence of invasive disease and meningitis was higher among children younger than 2 years of age (16.8 and 3.8, respectively). Serotypes 19, 14 and 6 accounted for 83% of the isolates. CONCLUSIONS: The age distribution of invasive pneumococcal disease and meningitis shows a peak in the first two years of life and a decline thereafter. Serotypes 19, 14 and 6 are those primarily responsible for invasive pneumococcal disease in children of this region of Spain.

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A procedure for the rapid determination of mono-, di- and tributyltin in water samples is described. The analytes are simultaneously ethylated and concentrated on a solid-phase microextraction fibre placed in the headspace over the sample for 2 min. The ethylated species are then separated and selectively quantified in only 90 s using a multicapillary gas chromatography column combined with atomic emission detection. The influence of blank signals and sampling conditions on the sensitivity of the method is described. Detection limits of 1-5 ng/l and relative standard deviations of 6-10% at concentrations of 20 ng/l were obtained.

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A simple procedure for the determination of six non-coplanar polychlorinated biphenyls (PCBs) in medium volumes of indoor air is described. Samples are forced at 6 m3/h through a device consisting of a quartz filter connected to the end of a conventional solid-phase extraction cartridge containing 60 mg of functionalized styrene-divinylbenzene. PCBs retained on the sorbent are directly eluted with 2 ml of hexane. Those associated to airborne particulate matter are microwave extracted in 10 min using 15 ml hexane-acetone (1:1). The proposed procedure is favorably compared to the use of polyurethane cylinders for the concentration of PCBs in terms of solvent consumption and rapidity of the desorption step. Furthermore, the functionalized sorbent showed higher breakthrough volumes than Amberlite XAD-2 for PCBs in gas phase. Quantification limits between 2 and 40 pg/m3 were obtained for six PCBs (from di- to heptachlorobiphenyls) using GC-electron-capture detection.

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