76 resultados para Multicenter Evaluation

em Instituto Politécnico do Porto, Portugal


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This study attempted to evaluate the influence of using an unstable shoe in muscle re-cruitment strategies and center of pressure (CoP) displacement after the application of an external perturba-tion. Fourteen healthy female subjects participated in this study. The electromyographic activity of medial ga-strocnemius, tibialis anterior, rectus femoris, biceps femoris, rectus abdominis and erector spinae muscles and the kinetic values to calculate the CoP were collected and analyzed after the application of an external pertur-bation with the subject in standing position, with no shoes and using unstable footwear. The results showed increased in medial gastrocnemius activity during the first compensatory postural adjustments and late com-pensatory postural adjustments when using an unstable shoe. There were no differences in standard deviation and maximum peak of anteroposterior displacement of CoP between measurements. From the experimental findings, one can conclude that the use of an unstable shoe leads to an increase in gastrocnemius activity with no increase in CoP displacement following an unexpected external perturbation.

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The Developmental Dysplasia of the Hip (DDH), also know as Congenital Dislocation of the Hip, is common in infants and children and may persist into adulthood. The radiographic interpretation is highly conditioned by appropriate patient positioning and image quality criteria. The main goal of this study is to demonstrate the value of radiographic evaluation of DDH. Through the retrospective analysis of 65 radiographs of the hips, only 2 (3.1%) female patients with 1-2 years of age presented radiographic findings of DDH. The inappropriate field size and the improper placement and size of the gonadal shields, were the most common errors observed.

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This paper starts with the analysis of the unusual inherence mechanism, from two aspects: accumulating and human error. We put forward twelve factors affected the decision of the emergency treatment plan in practice and summarized the evaluation index system combining with literature data. Then we screened out eighteen representative indicators by used the FDM expert questionnaire in the first phase. Hereafter, we calculated the weight of evaluation index and sorted them by the FAHP expert questionnaire, and came up with the frame of the evaluation rule by combined with the experience. In the end, the evaluation principles are concluded.

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In recent years Ionic Liquids (ILs) are being applied in life sciences. ILs are being produce with active pharmaceutical drugs (API) as they can reduce polymorphism and drug solubility problems [1] Also ILs are being applied as a drug delivery device in innovative therapies What is appealing in ILs is the ILs building up platform, the counter-ion can be carefully chosen in order to avoid undesirable side effects or to give innovative therapies in which two active ions are paired. This work shows ILs based on ampicillin (an anti-bacterial agent) and ILs based on Amphotericin B. Also we show studies that indicate that ILs based on Ampicillin could reverse resistance in some bacteria. The ILs produced in this work were synthetized by the neutralization method described in Ferraz et. al. [2] Ampicillin anion was combined with the following organic cations 1-ethyl-3-methylimidazolium, [EMIM]; 1-hydroxy-ethyl-3-methylimidazolium, [C2OHMIM]; choline, [cholin]; tetraethylammonium, [TEA]; cetylpyridinium, [C16pyr] and trihexyltetradecylphosphonium, [P6,6,6,14]. Amphotericin B was combined with [C16pyr], [cholin] and 1-metohyethyl-3-methylimidazolium, [C3OMIM]. The ILs-APIs based on ampicillin[2] were tested against sensitive Gram-negative bacteria Escherichia coli ATCC 25922 and Klebsiella pneumonia (clinical isolated), as well as on Gram positive Staphylococcus Aureus ATCC 25923, Staphylococcus epidermidis and Enterococcus faecalis. The arising resistance developed by bacteria to antibiotics is a serious public health threat and needs new and urgent measures. We study the bacterial activity of these compounds against a panel of resistant bacteria (clinical isolated strains): E. coli CTX M9, E. coli TEM CTX M9, E. coli TEM1, E. coli CTX M2, E. coli AmpC Mox2. In this work we demonstrate that is possible to produce ILs from anti-bacterial and anti-fungal compounds. We show here that the new ILs can reverse the bacteria resistance. With the careful choice of the organic cation, it is possible to create important biological and physic-chemical properties. This work also shows that the ion-pair is fundamental in ampicillin mechanism of action.

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In this paper, it was evaluated the total antioxidant capacity (TAC) of beverages using an electrochemical biosensor. The biosensor consisted on the purine base (guanine or adenine) electro-immobilization on a glassy carbon electrode surface (GCE). Purine base damage was induced by the hydroxyl radical generated by Fenton-type reaction. Five antioxidants were applied to counteract the deleterious effects of the hydroxyl radical. The antioxidants used were ascorbic acid, gallic acid, caffeic acid, coumaric acid and resveratrol. These antioxidants have the ability to scavenger the hydroxyl radical and protect the guanine and adenine immobilized on the GCE surface. The interaction carried out between the purinebase immobilized and the free radical in the absence and presence of antioxidants was evaluated by means of changes in the guanine and adenine anodic peak obtained by square wave voltammetry (SWV). The results demonstrated that the purine-biosensors are suitable for rapid assessment of TAC in beverages.

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Introduction: In the XXI Century ’s Society the scientific investigation process has been growing steadily , and the field of the pharmaceutical research is one of the most enthusiastic and relevant . Here, it is very important to correlate observed functional alterations with possibly modified drug bio distribution patterns . Cancer, inflammation and inf ection are processes that induce many molecular intermediates like cytokines, chemokines and other chemical complexes that can alter the pharmacokinetics of many drugs. One cause of such changes is thought to be the modulator action of these complexes in t he P - Glyco p rotein activity, because they can act like inducers/inhibitors of MDR - 1 expression. This protein results from the expression of MDR - 1 gene, and acts as an ATP energy - dependent efflux pump, with their substrates including many drugs , like antiretrovirals, anticancers, anti - infectives, immunosuppressants, steroids or opioids . Objectives: Because of the lack of methods to provide helpful information in the investigation of in vivo molecular changes in Pgp activity during infection/infl ammation processes, and its value in the explanation of the altered drug pharmacokinetic, this paper want to evaluate the potential utility of 99m Tc - Sestamibi scintigraphy during this kind of health sciences investigation. Although the a im is indeed to create a technique to the in vivo study of Pgp activity, this preliminary Project only reaches the in vitro study phase, assumed as the first step in a n evaluation period for a new tool development. Materials and Methods: For that reason , we are performing in vitro studies of influx and efflux of 99m Tc - Sestamibi ( that is a substrate of Pgp) in hepatocytes cell line (HepG2). We are interested in clarify the cellular behavior of this radiopharmaceutical in Lipopolysaccharide(LPS) stimulated cells ( well known in vitro model of inflammation) to possibly approve this methodology. To validate the results, the Pgp expression will be finally evaluated using Western Blot technique. Results: Up to this moment , we still don’t have the final results, but we have already enough data to let us believe that LPS stimulation induce a downregulation of MDR - 1, and consequently Pgp, which could conduce to a prolonged retention of 99m Tc - Sestamibi in the inflamed cells . Conclusions: If and when this methodology demonstrate the promising results we expect, one will be able to con clude that Nuclear Medicine is an important tool to help evidence based research also on this specific field .

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In order to overcome the problems associated with low water solubility, and consequently low bioavailability of active pharmaceutical ingredients (APIs), herein we explore a modular ionic liquid synthetic strategy for improved APIs. Ionic liquids containing l-ampicillin as active pharmaceutical ingredient anion were prepared using the methodology developed in our previous work, using organic cations selected from substituted ammonium, phosphonium, pyridinium and methylimidazolium salts, with the intent of enhancing the solubility and bioavailability of l-ampicillin forms. In order to evaluate important properties of the synthesized API-ILs, the water solubility at 25 °C and 37 °C (body temperature) as well as octanol–water partition coefficients (Kow's) and HDPC micelles partition at 25 °C were measured. Critical micelle concentrations (CMC's) in water at 25 °C and 37 °C of the pharmaceutical ionic liquids bearing cations with surfactant properties were also determined from ionic conductivity measurements.

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QuEChERS method was evaluated for extraction of 16 PAHs from fish samples. For a selective measurement of the compounds, extracts were analysed by LC with fluorescence detection. The overall analytical procedure was validated by systematic recovery experiments at three levels and by using the standard reference material SRM 2977 (mussel tissue). The targeted contaminants, except naphthalene and acenaphthene, were successfully extracted from SRM 2977 with recoveries ranging from 63.5–110.0% with variation coefficients not exceeding 8%. The optimum QuEChERS conditions were the following: 5 g of homogenised fish sample, 10 mL of ACN, agitation performed by vortex during 3 min. Quantification limits ranging from 0.12– 1.90 ng/g wet weight (0.30–4.70 µg/L) were obtained. The optimized methodology was applied to assess the safety concerning PAHs contents of horse mackerel (Trachurus trachurus), chub mackerel (Scomber japonicus), sardine (Sardina pilchardus) and farmed seabass (Dicentrarchus labrax). Although benzo(a)pyrene, the marker used for evaluating the carcinogenic risk of PAHs in food, was not detected in the analysed samples (89 individuals corresponding to 27 homogenized samples), the overall mean concentration ranged from 2.52 l 1.20 ng/g in horse mackerel to 14.6 ± 2.8 ng/ g in farmed seabass. Significant differences were found between the mean PAHs concentrations of the four groups.

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The industrial manufacturing of metallic objects results in a high level of foundry waste sands that may contain toxic compounds such as formaldehyde. The formaldehyde content of foundry waste sands was evaluated by liquid chromatography. Samples were collected during various steps of the industrial processes. Results showed that the phenolic alkaline process generated waste sands with higher formaldehyde content than the furanic process; the highest value was 7.6×10-3% (w/w). In this work, formaldehyde content decreased with time in all of the samples studied, revealing that most formaldehyde was released to the occupational environment.

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The evaluation of benzene in different environments such as indoor (with and without tobacco smoke), a city area, countryside, gas stations and near exhaust pipes from cars running on different types of fuels was performed. The samples were analyzed using gas chromatography (GC) with flame ionization detection (FID) and tandem mass spectrometric detection (MS/MS) (to confirm the identification of benzene in the air samples). Operating conditions for the GC-MS analysis were optimized as well as the sampling and sample preparation. The results obtained in this work indicate that i) the type of fuel directly influences the benzene concentration in the air. Gasoline with additives provided the highest amount of benzene followed by unleaded gasoline and diesel; ii) the benzene concentration in the gas station was always higher than the advisable limit established by law (5 μg m−3) and during the unloading of gasoline the achieved concentration was 8371 μg m−3; iii) the data from the countryside (Taliscas) and the urban city (Matosinhos) were below 5 μg m−3 except 5 days after a fire on a petroleum refinery plant located near the city; iv) it was proven that in coffee shops where smoking is allowed the benzene concentration is higher (6 μg m−3) than in coffee shops where this is forbidden (4 μg m−3). This method may also be helpful for environmental analytical chemists who use GC-MS/MS for the confirmation or/and quantification of benzene.

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A flow injection analysis (FIA) system comprising a cysteine selective electrode as detection system was developed for determination of this amino acid in pharmaceuticals. Several electrodes were constructed for this purpose, having PVC membranes with different ionic exchangers and mediator solvents. Better working characteristics were attained with membranes comprising o-nitrophenyl octyl ether as mediator solvent and a tetraphenylborate based ionic-sensor. Injection of 500 µL standard solutions into an ionic strength adjuster carrier (3x10-3 M) of barium chloride flowing at 2.4mL min-1, showed linearity ranges from 5.0x10-5 to 5.0x10-3 M, with slopes of 76.4±0.6mV decade-1 and R2>0.9935. Slope decreased significantly under the requirement of a pH adjustment, selected at 4.5. Interference of several compounds (sodium, potassium, magnesium, barium, glucose, fructose, and sucrose) was estimated by potentiometric selectivity coefficients and considered negligible. Analysis of real samples were performed and considered accurate, with a relative error to an independent method of +2.7%.

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In this paper, a biosensor based on a glassy carbon electrode (GCE) was used for the evaluation of the total antioxidant capacity (TAC) of flavours and flavoured waters. This biosensor was constructed by immobilising purine bases, guanine and adenine, on a GCE. Square wave voltammetry (SWV) was selected for the development of this methodology. Damage caused by the reactive oxygen species (ROS), superoxide radical (O2·−), generated by the xanthine/xanthine oxidase (XOD) system on the DNA-biosensor was evaluated. DNA-biosensor encountered with oxidative lesion when it was in contact with the O2·−. There was less oxidative damage when reactive antioxidants were added. The antioxidants used in this work were ascorbic acid, gallic acid, caffeic acid, coumaric acid and resveratrol. These antioxidants are capable of scavenging the superoxide radical and therefore protect the purine bases immobilized on the GCE surface. The results demonstrated that the DNA-based biosensor is suitable for the rapid assess of TAC in beverages.

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A flow injection analysis (FIA) system having a chlormequat selective electrode is proposed. Several electrodes with poly(vinyl chloride) based membranes were constructed for this purpose. Comparative characterization suggestedthe use of membrane with chlormequat tetraphenylborate and dibutylphthalate. On a single-line FIA set-up, operating with 1x10-2 mol L-1 ionic strength and 6.3 pH, calibration curves presented slopes of 53.6±0.4mV decade-1 within 5.0x10-6 and1.0x10-3 mol L-1, andsquaredcorrelation coefficients >0.9953. The detection limit was 2.2x10-6 mol L-1 and the repeatability equal to ±0.68mV (0.7%). A dual-channel FIA manifold was therefore constructed, enabling automatic attainment of previous ionic strength andpH conditions and thus eliminating sample preparation steps. Slopes of 45.5±0.2mV decade -1 along a concentration range of 8.0x10-6 to 1.0x10-3 mol L-1 with a repeatability ±0.4mV (0.69%) were obtained. Analyses of real samples were performed, and recovery gave results ranging from 96.6 to 101.1%.