Synthetic MRI in subarachnoid haemorrhage.

AIM: To evaluate the reliability of synthetic magnetic resonance imaging (SyMRI) for detecting complications associated with subarachnoid haemorrhage (SAH), such as ischaemic lesions, hydrocephalus, or bleeding complications. MATERIALS AND METHODS: Twenty patients with SAH, who underwent a conventional brain MRI and a SyMRI on a 3 T MRI machine. Comparable conventional and synthetic T2-weighted fluid attenuated inversion recovery (FLAIR) images were acquired. The presence of ischaemic lesions, hydrocephalus, extra-axial blood collections as well as the volumes of grey matter (GMv), white matter (WMv), and cerebrospinal (CSFv) were compared. The acquisition times of both sequences was also analysed. RESULTS: The concordance between the two techniques was excellent for the detection of ischaemic lesions and extra-axial collections (kappa = 0.80 and 0.88 respectively) and good for the detection of hydrocephalus (kappa = 0.69). No significant differences were detected in the number of ischaemic lesions (p=0.31) or in the Evans index (p=0.11). The WMv and CSFv measures were also similar (p=0.18 and p=0.94, respectively), as well as the volume of ischaemic lesions (p=0.79). Compared to conventional MRI, the SyMRI acquisition time was shorter regardless of the number of sections (32% and 6% time reduction for 4 or 3 mm section thickness, respectively). CONCLUSIONS: SyMRI allows the detection of potential complications of SAH in a similar way to conventional MRI with a shorter acquisition time.

A Signal Processing Approach to Pharmacokinetic Data Analysis.

The connection between pharmacokinetic models and system theory has been established for a long time. In this approach, the drug concentration is seen as the output of a system whose input is the drug administered at different times. In this article we further explore this connection. We show that system theory can be used to easily accommodate any therapeutic regime, no matter its complexity, allowing the identification of the pharmacokinetic parameters by means of a non-linear regression analysis. We illustrate how to exploit the properties of linear systems to identify non-linearities in the pharmacokinetic data. We also explore the use of bootstrapping as a way to compare populations of pharmacokinetic parameters and how to handle the common situation of using multiple hypothesis tests as a way to distinguish two different populations. Finally, we demonstrate how the bootstrap values can be used to estimate the distribution of derived parameters, as can be the allometric scale factors.

Encefalopatía transitoria por contraste tras la embolización de la arteria carótida interna previa a la cirugía de carcinoma nasofaríngeo / Transient contrast-induced encephalopathy after internal carotid artery embolisation prior to surgery for nasopharyngeal carcinoma

No disponible

La relevancia de la anhidrosis en el síndrome de Horner. A propósito de una imagen / The relevance of anhidrosis in Horner syndrome: Analysis of an image

No disponible

Trombosis basilar por disección vertebral secundaria a bloqueo del plexo braquial / Basilar artery thrombosis caused by vertebral dissection secondary to brachial plexus block

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Subjective memory complaints in elderly: relationship with health status, multimorbidity, medications, and use of services in a population-based study.

BACKGROUND: This study examines the associations between subjective memory complaints (SMC) and health variables: multimorbidity, presence of certain diseases, health perceived state, difficulties seeing and hearing, pain, and use of medications and health services. Furthermore, we aim to identify risk groups based on multimorbidity and calculate the effect size for each of these relationships. METHODS: Cross-sectional epidemiological study using a face-to-face interview with a structured questionnaire. SAMPLE SIZE: 1,342 people aged 65 years and older taken from a random sample of the census tracts. SMC were studied using questions regarding memory complaints. RESULTS: Multimorbidity and polypharmacy are associated with SMC, so are impaired vision and hearing. SMC are more frequently present in people who use health services more intensively and exhibit reduced functional activity as a result of diseases. With respect to specific diseases, only cerebrovascular accidents and chronic constipation were associated with SMC. In regression analysis, predictors of SMC were vision and hearing impairment, poor self-perceived health, pain, and general practitioner visits. However, the effect size of these factors is low. The variables that indicate risk groups are number of diseases, reduced functional activity, hearing impairment, and poor self-perceived health. CONCLUSIONS: Memory complaints are a heterogeneous phenomenon. Our results confirm that multimorbidity, polypharmacy, greater use of health services, pain, and poor self-perceived health are associated with SMC. We identified two risk groups with a high percentage of complaints and a healthy group with a low percentage. Detecting these factors and these risk and healthy groups is useful in achieving proper patients management.

Influence of input material and operational performance on the physical and chemical properties of MSW compost.

Certain controversy exists about the use of compost from MSW (municipal solid waste) and, specifically, from the organic fraction of MSW that has not been separated at the source. In this case, the final composition of MSW compost is related to the performance of the separation process in MBT (Mechanical and Biological Treatment) plants as well as the composition of raw materials and the particular features of composting systems. In an effort to investigate the quality of MSW compost, 30 samples of this product obtained from 10 different MBT plants were studied. The main physical and chemical properties were analyzed and were compared with the requirements of current legislation. The composting systems used to produce these compost samples were studied and the input materials were characterized. The results reveal that the heavy metal content in MSW compost was below the legal restrictions in all samples but one; however, in most of them the percentage of Pb was high. The fertilizing potential of MSW compost has been demonstrated by its high nutrient concentrations, particularly N, K, P, Ca and Mg. Nevertheless, here the percentage of inert impurities with a size larger than 2 mm, such as plastic or glass, was seen to be excessively high exceeding in some cases the legal limit. The source of such pollution lies in the composting inputs, OFMSW (organic fraction of MSW), which showed high percentages of improper materials such as plastic (9%) or glass (11%). Accordingly, the performance of the sorting stage for the collection of the raw material must be improved, as must the refining process, since this does not remove the necessary amounts of these impurities from the final compost.

Analysis of the presence of improper materials in the composting process performed in ten MBT plants.

Composting of the organic fraction of municipal solid waste (OFMSW) reduces the amount of biodegradable waste landfilled. However, the final product or compost used as organic soil amendment shows a large presence of improper materials and alarming concentrations of heavy metals. In this work, 30 samples of OFMSW before and after composting have been characterized to determine qualitatively and quantitatively this contamination and its origin. In addition, technical features of the equipment installed in 10 waste treatment plants have been assessed because of their influence on the streams involved in the composting process. Results show 78.2% of the samples stabilized by composting to be organic matter and the rest corresponds to improper materials, mainly paper, plastic and glass. Origin is due to the composting feedstocks, the OFMSW obtained by size separation in trommels which, due to non-source separation and poor selectivity, contains one third of impurities. In seven of the 30 samples household batteries were found.

Effective antiproliferative effect of meloxicam on prostate cancer cells: development of a new controlled release system.

Recent studies have shown that COX-2 inhibitors, such as meloxicam, have demonstrated promising results when used with chemotherapy. Based on these findings, this is the first study in which the antiproliferative effect of meloxicam is investigated on two prostate cancer cell lines (PC3 and DU-145). We have also evaluated if this antiproliferative effect is dose- and/or time-dependent. Meloxicam is assayed at a concentration range of 10-800 microM for 24, 48 and 72 h. Our results reveal that meloxicam has a selective dose- and time-dependent antiproliferative effect against PC3 but not against DU-145 cells. In PC3 cells the IC(50) decreased from 740 microM at 24 h to 515 microM at 72 h after meloxicam treatment. Chemoembolization based on microspheres has been emerged as a novel and promising way for antitumoural therapy; therefore, in our study we have developed and characterized a new controlled release system consisting of biodegradable PLGA/PEG-derivative meloxicam microspheres. The optimized formulation has a mean particle size of 13.06+/-0.09 microm, mean encapsulation efficiency of 58.44+/-4.53% and releases 0.45+/-0.05 microg meloxicam/day/mg microspheres between days 3 and 28 of the in vitro release assay. In conclusion, we should consider meloxicam as a possible adjuvant agent in the treatment of prostate cancer.

PLGA/PEG-derivative polymeric matrix for drug delivery system applications: Characterization and cell viability studies.

The incorporation of additives such as polyoxyethylated oleic acid glycerides (PEG-derivative) can modify the release of drugs from microparticles. PEG-derivative decreases the release rate of drugs that are dissolved in PLGA matrices but if un-dissolved the initial release rate slightly increases. To clarify this behaviour the influence of adding PEG-derivative in the preparation of microspheres was investigated by scanning electron microscopy, differential scanning calorimetry, gel permeation chromatography, nuclear magnetic resonance and infrared spectroscopy. Cytotoxicity of this resulting PLGA/PEG-derivative matrix was evaluated in cell lines (fibroblasts) which are more reproducible but less specific and in primary cell cultures (splenocytes and human leucocytes) which have the advantage of their specificity. Scanning electron microscopy revealed that PLGA/PEG-derivative microspheres exhibited small surface concavities with a highly porous polymeric matrix. The incorporation of PEG-derivative caused a slight reduction in the T(g) values of PLGA. In vitro degradation studies showed that PEG-derivative remains within the microspheres as long as the matrix does. This PLGA/PEG-derivative matrix was well tolerated exhibiting cell viabilities similar to PLGA microspheres and can be used to modulate the release of drugs from microparticulate systems destined for parenteral administration.