Acute inactivation of the contralesional hemisphere for longer durations improves recovery after cortical injury

Au cours des dernières années, des méthodes non-invasives de stimulations permettant de moduler l’excitabilité des neurones suivant des lésions du système nerveux central ont été développées. Ces méthodes sont maintenant couramment utilisées pour étudier l’effet de l’inhibition du cortex contralésionnel sur la récupération motrice à la suite d’un accident vasculocérébral (AVC). Bien que plusieurs de ces études rapportent des résultats prometteurs, les paramètres permettant une récupération optimale demeurent encore inconnus. Chez les patients victimes d'un AVC, il est difficile de débuter les traitements rapidement et d'initier l’inhibition dans les heures suivant la lésion. L'impact de ce délai est toujours inconnu. De plus, aucune étude n’a jusqu’à maintenant évalué l’effet de la durée de l’inhibition sur la récupération du membre parétique. Dans le laboratoire du Dr Numa Dancause, nous avons utilisé un modèle bien établi de lésion ischémique chez le rat pour explorer ces questions. Nos objectifs étaient d’évaluer 1) si une inactivation de l’hémisphère contralésionnel initiée dans les heures qui suivent la lésion peut favoriser la récupération et 2) l’effet de la durée de l’inactivation sur la récupération du membre parétique. Suite à une lésion dans le cortex moteur induite par injections d’un vasoconstricteur, nous avons inactivé l’hémisphère contralésionnel à l’aide d’une pompe osmotique assurant l’infusion continue d’un agoniste du GABA (Muscimol). Dans différents groupes expérimentaux, nous avons inactivé l’hémisphère contralésionnel pour une durée de 3, 7 et 14 jours suivant la lésion. Dans un autre groupe, le Muscimol a été infusé pour 14 jours mais à un débit moindre de façon à pouvoir étudier le lien entre la fonction du membre non-parétique et la récupération du membre parétique. Les données comportementales de ces groupes ont été comparées à celles d’animaux ayant récupéré de façon spontanée d'une lésion similaire. Nos résultats indiquent que l’augmentation de la durée de l’inactivation (de 3 à 14 jours) accélère la récupération du membre parétique. De plus, les deux groupes ayant reçu une inactivation d'une durée de 14 jours ont montré une plus grande récupération fonctionnelle que le groupe n’ayant pas reçu d’inactivation de l’hémisphère contralésionnel, le groupe contrôle. Nos résultats suggèrent donc que l’inactivation de l’hémisphère contralésionnel initiée dans les heures suivant la lésion favorise la récupération du membre parétique. La durée d’inhibition la plus efficace (14 jours) dans notre modèle animal est beaucoup plus longues que celles utilisées jusqu’à maintenant chez l’homme. Bien qu’il soit difficile d’extrapoler la durée idéale à utiliser chez les patients à partir de nos données, nos résultats suggèrent que des traitements de plus longue durée pourraient être bénéfiques. Finalement, un message clair ressort de nos études sur la récupération fonctionnelle après un AVC: dans le développement de traitements basés sur l’inhibition de l’hémisphère contralésionnel, la durée de l’inactivation est un facteur clef à considérer.

Factores de riesgo asociados a mortalidad en postoperatorio de fractura de cadera en adulto mayor

Introducción: La fractura de cadera es un evento frecuente con una mortalidad alta a nivel mundial, sin embargo, poco énfasis se hace a los posibles factores de riesgo modificables. Materiales y métodos: Se realizó un estudio analítico de casos y controles con el objetivo de identificar factores de riesgo del postoperatorio de fractura de cadera asociados a mortalidad a 90 días. Se revisaron 122 historias clínicas desde enero del 2000 hasta diciembre del 2009 en la Fundación CardioInfantil, 91 historias cumplieron los criterios de inclusión. Se agruparon en casos y controles: en el primer grupo 18 pacientes que fallecen a los 90 días y, en el segundo grupo 77 pacientes que no fallecen. Se hizo un análisis estadístico mediante chi cuadrado, test de Fisher y regresión logística. Resultados: La mortalidad a 90 días fue del 19%. Las variables asociadas con mortalidad estadísticamente significativas fueron: número de comorbilidades (p=0,027), hemoglobina (p=0,031), delirium pre quirúrgico (OR 6,1 p=0,05). La deambulación al alta mostró ser factor protector (OR 0,15 p=0,003). Las complicaciones que mostraron asociación con mortalidad fueron: infección (OR 27 p=0,01), hemorragia (OR 14 p=0,05), y delirum post quirúrgico (OR 8,2 0,01). Conclusión: Se encontró que la hemoglobina pre quirúrgica, delirium, número de comorbilidades, la no deambulación al alta, la infección post operatoria y la hemorragia post quirúrgica son variables asociadas a mortalidad a los 90 días postoperatorio de fractura de cadera fueron. Es necesario realizar estudios donde se intervengan estas variables y evaluar posibles cambios en la mortalidad

Análisis de la depresión en el adulto mayor en la encuesta nacional de demografía y salud 2010

En Colombia como en otros países del mundo se está viviendo un proceso de transición epidemiológica y cada vez es más importante la población, aumentando el número de adultos mayores, en los que la depresión es una enfermedad que genera impacto en la morbililidad y mortalidad, y pocos estudios nacionales se han enfocado en analizar su comportamiento y sus factores asociados. Metodología: Estudio de corte transversal sobre los datos de la encuesta nacional de demografía y salud del año 2010 (ENDS 2010) que encuesto 50.000 hogares con 17.574 adultos mayores encuestados. Se realizó una regresión logística binaria y múltiple para establecer las variables asociadas a la depresión. Resultados: Se encontró una prevalencia global de 9,5%, siendo mayor para el sexo femenino (11,5%, OR =1,74), menor prevalencia de depresión a medida que aumenta la escolaridad (OR=0.14), mayor depresión en presencia de discapacidad (OR=14,21) y en las comorbilidades como enfermedades cerebrales (OR=2.09), cardiacas (OR=1.49), diabetes (OR=1.19), Alzheimer (OR=2,13) entre otras, no se encontró asociación con variables como edad, estado civil. Discusión: El comportamiento de la depresión en adultos mayores en la población estudiada es similar a la de otros países, se deben hacer estudios prospectivos y de intervención para establecer mejor las variables relacionadas.

Revision sistemática: Factores asociados a colonización e infección por bacterias gram negativas resistentes a carbapenemicos

INTRODUCCIÓN: Los carbapenémicos (CP) son una de las últimas líneas de tratamiento para infecciones por microorganismos multirresistentes (MDR), especialmente Gram-negativos productores de betalactamasas de espectro extendido. Es creciente la preocupación a nivel mundial por el aumento de aislamientos resistentes a CP, en EEUU hasta 60% de las infecciones nosocomiales son causadas por bacterias MDR. En la Unión Europea, cerca de 25.000 pacientes mueren anualmente por esta causa. En Latinoamérica hay una tendencia creciente en las tasas de resistencia.OBJETIVO: Identificar y describir factores protectores o de riesgo, relacionados con colonización o infección por Gram negativos resistentes a CP en pacientes adultos hospitalizados, mediante una revisión sistemática de la literatura.MÉTODOS: Revisión sistemática de literatura, búsqueda de estudios observacionales analíticos en las bases de datos PubMed, Embase, Scopus, BVS, Scielo y búsqueda de literatura gris, publicados desde el 01/01/2004 al 15/04/2015. Se evalúo la calidad de los estudios con escala Newcastle-Ottawa y FLC Osteba. RESULTADOS: Se seleccionaron 36 estudios de alta calidad, diseño de casos y controles. Los factores de riesgo estadísticamente significativos observados son estancia en UCI OR:36.46, insuficiencia renal aguda OR:6.23, diálisis OR:10.80 ventilación mecánica OR:17.5, cateterismo vesical OR:14.3, uso de carbapenémicos OR:18,52,quinolonas OR17.30, cefepime OR:28.05, glicopéptidos OR:19.1; metronidazol OR:4.17, p:0.03, colistina OR:12.1, linezolid OR:7 CONCLUSIÓN: Pese a que hay alta heterogeneidad en las variables incluidas en los estudios, se encontró que los factores de riesgo principales para adquirir GNR-CP en pacientes hospitalizados son: antecedente de insuficiencia renal aguda y diálisis, ventilación mecánica, cateterismo vesical, estancia en UCI y uso previo de antibióticos carbapenémicos, quinolonas, cefepime, glicopéptidos, metronidazol, linezolid y colistina. No se hallaron factores protectores. factores de riesgo

Risk factors for tick attachment to smallholder dairy cattle in Tanzania

A cross-sectional study was conducted in Tanga and Iringa regions of Tanzania, and a longitudinal study in Tanga, to investigate tick-control methods and other factors influencing tick attachment to the cattle of smallholder dairy farms. Most farmers reported applying acaricides at intervals of 1-2 weeks, most used acaricides that require on-farm dilution and most farmers incorrectly diluted the acaricides. Rhipicephalus appendiculatus and Boophilus spp. ticks were those most-frequently encountered on the cattle, but few cattle carried ticks of any species (only 13 and 4.6% of tick counts of the cattle yielded adult R. appendiculatus and Boophilus spp., respectively). Animals were more likely to carry one or more adult Boophilus spp. ticks if they also carried one or more R. appendiculatus adults (OR = 14.4, CI = 9.2, 22.5). The use of pour-on acaricides was associated with lower odds that animals carried a R. appendiculatus tick (OR = 0.29, CI = 0. 18, 0.49) but higher odds that they carried a Boophilus spp. tick (OR = 2.48, CI = 1.55, 3.97). Animals > 4 months old and those with a recent history of grazing had higher odds of carrying either a R. appendiculatus (ORs = 3.41 and 2.58, CIs = 2.34, 4.98 and 1.80, 3.71), or a Boophilus spp. tick (ORs = 5.70 and 2.18, CIs = 2.34, 4.98 and 1.49. 3.25), but zero-grazing management did not prevent ticks attaching to cattle even when combined with high-frequency acaricide treatments. The odds that animals carried ticks varied amongst the agro-ecological zones (AEZs) and administrative districts where the farms were situated-but there was still considerable residual variation in tick infestation at the farm level. (c) 2004 Elsevier B.V. All rights reserved.

Influence of birth weight on gene regulators of lipid metabolism and utilization in subcutaneous adipose tissue and skeletal muscle of neonatal pigs.

Epidemiological studies suggest that low-birth weight infants show poor neonatal growth and increased susceptibility to metabolic syndrome, in particular, obesity and diabetes. Adipose tissue development is regulated by many genes, including members of the peroxisome proliferator-activated receptor (PPAR) and the fatty acid-binding protein (FABP) families. The aim of this study was to determine the influence of birth weight on key adipose and skeletal muscle tissue regulating genes. Piglets from 11 litters were ranked according to birth weight and 3 from each litter assigned to small, normal, or large-birth weight groups. Tissue samples were collected on day 7 or 14. Plasma metabolite concentrations and the expression of PPARG2, PPARA, FABP3, and FABP4 genes were determined in subcutaneous adipose tissue and skeletal muscle. Adipocyte number and area were determined histologically. Expression of FABP3 and 4 was significantly reduced in small and large, compared with normal, piglets in adipose tissue on day 7 and in skeletal muscle on day 14. On day 7, PPARA and PPARG2 were significantly reduced in adipose tissue from small and large piglets. Adipose tissue from small piglets contained more adipocytes than normal or large piglets. Birth weight had no effect on adipose tissue and skeletal muscle lipid content. Low-birth weight is associated with tissue-specific and time-dependent effects on lipid-regulating genes as well as morphological changes in adipose tissue. It remains to be seen whether these developmental changes alter an individual's susceptibility to metabolic syndrome.

Temporal sensitivity of rice seed development from spikelet fertility to viable mature seed to extreme-temperature

Extreme temperature during reproductive development affects rice (Oryza sativa L.) yield and seed quality. A controlled-environment reciprocal-transfer experiment was designed where plants from two japonica cultivars were grown at 28/24 ⁰C and moved to 18/14 ⁰C and vice versa, or from 28/24 to 38/34 ⁰C and vice versa, for 7-d periods to determine the respective temporal pattern of sensitivity of spikelet fertility, yield, and seed viability to each temperature extreme. Spikelet fertility and seed yield per panicle were severely reduced by extreme temperature in the 14 d period prior to anthesis; and both cultivars were affected at 38/34 ⁰C while only cv. Gleva was affected at 18/14 ºC. The damage was greater the earlier the panicles were stressed within this period. Later-exserted panicles compensated only partly for yield loss. Seed viability was significantly reduced by 7-d exposure to 38/34 ⁰C or 18/14 ⁰C at 1 to 7 and 1 to 14 d after anthesis, respectively, in cv. Gleva. Cultivar Taipei 309 was not affected by 7 d exposure at 18/14 ⁰C; and no consistent temporal pattern of sensitivity was evident at 38/34 ⁰C. Hence, brief exposure to low or high temperature was most damaging to spikelet fertility and yield 14 to 7 d before anthesis, coinciding with microsporogenesis; and it was almost as damaging around anthesis. Seed viability was most vulnerable to low or high temperature in the 7 or 14 d after anthesis, when histodifferentiation occurs.

Thyroid hormones alter the adenine nucleotide hydrolysis in adult rat blood serum

The effects of ATP, ADP, and adenosine in the processes of platelet aggregation, vasodilatation, and coronary flow have been known for many years. The sequential hydrolysis of ATP to adenosine by soluble nucleotidases constitutes the main system for rapid inactivation of circulating adenine nucleotides. Thyroid disorders affect a number of biological factors including adenosine levels in different fractions. Then, we intend to investigate if the soluble nucleotidases responsible for the ATP, ADP, and AMP hydrolysis are affected by variations in the thyroid hormone levels in blood serum from adult rats. Hyperthyroidism was induced by daily intraperitoneal injections of L-thyroxine (T4) (2.5 and 10.0 mu g/100 g body weight, respectively) for 7 or 14 days. Hypothyroidism was induced by thyroidectomy and methimazole (0.05%) added to their drinking water during 7 or 14 days. The treatments efficacy was confirmed by determination of hemodynamic parameters and cardiac hypertrophy evaluation. T4 treatment predominantly inhibited, and hypothyroidism (14 days after thyroidectomy) predominantly increased the ATP, ADP, and AMP hydrolysis in rat blood serum. These results suggest that both excess and deficiency of thyroid hormones can modulate the ATP diphosphohydrolase and 5`-nucleotidase activities in rat blood serum and consequently modulate the effects mediated by these enzymes and their products in vascular system. (C) 2010 International Union of Biochemistry and Molecular Biology, Inc.

Maximal inflammatory response benefits syngeneic skin graft acceptance

Objective: We investigated the influence of acute inflammation in skin isograft acceptance. Methods: Two mouse lines selected for maximal (AIR(MAX)) or minimal inflammatory response (AIR(MIN)) were transplanted with syngeneic skin. Cellular infiltrates and cytokine production were measured 1, 3, 7 or 14 days post-transplantation. The percentage of CD4(+) CD25(+) Foxp3(+) cells in the lymph nodes was also evaluated. Results: Grafts were totally accepted in 100% of AIR(MAX) and in 26% of AIR(MIN) mice. In the latter, partial acceptance was observed in 74% of the animals. Emigrated cells were basically PMN and were enhanced in AIR(MAX) transplants. IL-10 production by graft infiltrating cells showed no interline differences. IFN-gamma was increased in AIR(MIN) grafts at day 14 and lower percentages of CD4(+)CD25(+)Foxp3(+) cells in the lymph nodes were observed in these mice. Conclusions: Our data suggest that differences in graft acceptance might be due to a lack of appropriate regulation of the inflammatory response in AIR(MIN) mice compromising the self/non-self recognition.

Correlation of the in vitro antifungal drug susceptibility with the in vivo activity of fluconazole in a murine model of cerebral infection caused by Cryptococcus gattii

Forty Cryptococcus gattii strains were submitted to antifungal susceptibility testing with fluconazole, itraconazole, amphotericin B and terbinafine. The minimum inhibitory concentration (MIC) ranges were 0.5-64.0 for fluconazole, < 0.015-0.25 for itraconazole, 0.015-0.5 for amphotericin B and 0.062-2.0 for terbinafine. A bioassay for the quantitation of fluconazole in murine brain tissue was developed. Swiss mice received daily injections of the antifungal, and their brains were withdrawn at different times over the 14-day study period. The drug concentrations varied from 12.98 to 44.60 mu g/mL. This assay was used to evaluate the therapy with fluconazole in a model of infection caused by C. gattii. Swiss mice were infected intracranially and treated with fluconazole for 7, 10 or 14 days. The treatment reduced the fungal burden, but an increase in fungal growth was observed on day 14. The MIC for fluconazole against sequential isolates was 16 mu g/mL, except for the isolates obtained from animals treated for 14 days (MIC = 64 mu g/mL). The quantitation of cytokines revealed a predominance of IFN-gamma and IL-12 in the non-treated group and elevation of IL-4 and IL-10 in the treated group. Our data revealed the possibility of acquired resistance during the antifungal drug therapy.

Discrepancies in solar irradiation data for Stockholm and Athens

The aim of this study is to evaluate the variation of solar radiation data between different data sources that will be free and available at the Solar Energy Research Center (SERC). The comparison between data sources will be carried out for two locations: Stockholm, Sweden and Athens, Greece. For the desired locations, data is gathered for different tilt angles: 0°, 30°, 45°, 60° facing south. The full dataset is available in two excel files: “Stockholm annual irradiation” and “Athens annual irradiation”. The World Radiation Data Center (WRDC) is defined as a reference for the comparison with other dtaasets, because it has the highest time span recorded for Stockholm (1964–2010) and Athens (1964–1986), in form of average monthly irradiation, expressed in kWh/m2. The indicator defined for the data comparison is the estimated standard deviation. The mean biased error (MBE) and the root mean square error (RMSE) were also used as statistical indicators for the horizontal solar irradiation data. The variation in solar irradiation data is categorized in two categories: natural or inter-annual variability, due to different data sources and lastly due to different calculation models. The inter-annual variation for Stockholm is 140.4kWh/m2 or 14.4% and 124.3kWh/m2 or 8.0% for Athens. The estimated deviation for horizontal solar irradiation is 3.7% for Stockholm and 4.4% Athens. This estimated deviation is respectively equal to 4.5% and 3.6% for Stockholm and Athens at 30° tilt, 5.2% and 4.5% at 45° tilt, 5.9% and 7.0% at 60°. NASA’s SSE, SAM and RETScreen (respectively Satel-light) exhibited the highest deviation from WRDC’s data for Stockholm (respectively Athens). The essential source for variation is notably the difference in horizontal solar irradiation. The variation increases by 1-2% per degree of tilt, using different calculation models, as used in PVSYST and Meteonorm. The location and altitude of the data source did not directly influence the variation with the WRDC data. Further examination is suggested in order to improve the methodology of selecting the location; Examining the functional dependence of ground reflected radiation with ambient temperature; variation of ambient temperature and its impact on different solar energy systems; Im pact of variation in solar irradiation and ambient temperature on system output.

Economic evaluation alongside a phase II, multi-centre, randomised controlled trial of very early rehabilitation after stroke (AVERT)

BACKGROUND/PURPOSE: The effectiveness and costs of very early rehabilitation after stroke are unknown. This study assessed the cost effectiveness of very early mobilisation in addition to standard care (VEM) compared with standard care alone (SC). METHODS: Cost-effectiveness analysis alongside a phase II, multi-centre, randomised controlled trial (RCT) with blinded outcome assessments. Less than 24 h after stroke, patients were recruited from two stroke units and randomised to receive VEM or SC. The intervention continued until discharge or 14 days, whichever was sooner. The efficacy measure was a dichotomised modified Rankin Scale (mRS) at 3 months with mRS < or =2 representing good outcome. Costs were determined from medical records and patient interviews at 3, 6 and 12 months. National average (where available) or local costs were applied for the reference year 2004. Differences in mean total costs at 3 and 12 months were tested using t test assuming unequal variances. An incremental cost-effectiveness ratio was calculated and probabilistic uncertainty analysis was undertaken. RESULTS: The sample consisted of 38 VEM and 33 SC patients. A trend for good outcome with VEM compared to SC was found (adjusted OR 4.10, 95% CI 0.99-16.88, p = 0.051). Patients receiving VEM incurred significantly less costs at 3 months (AUD 13,559) compared with SC (AUD 21,860; p = 0.02). This difference in mean per patient total cost persisted at the 12-month assessment (VEM: AUD 17,564; SC: AUD 29,750; p = 0.03). VEM was found to be a 'dominant' (more effective, less cost) intervention when compared to SC at 3 months. CONCLUSION: These findings provide preliminary evidence that VEM is likely to be cost-effective. A large RCT is currently underway to confirm the cost effectiveness of VEM.

Evaluation of nasopharyngeal oxygen, nasal prongs and facemask oxygen therapy devices in adult patients: a randomised crossover trial

Nasopharyngeal oxygen (NPO) therapy may overcome some of the difficulties associated with nasal prongs and facemask oxygen delivery devices. In response to a lack of published studies of NPO therapy in adults, we conducted a prospective randomised crossover trial to compare the effectiveness of NPO, nasal prongs (NP) and facemasks (FM) when used in an adult population (n=37) from the intensive care unit and general hospital wards. We measured oxygen saturation (Sp[O.sub.2]) using pulse oximetry, oxygen flow (litres per minute), respiration rate (per minute) and comfort using a horizontal visual analogue scale. All three devices were effective in maintaining a Sp[O.sub.2] of [greater than or equal to]95% (NP 97.0[+ or -]1.9, NPO 97.7[+ or -]1.7, FM 98.8[+ or -]1.3%). NPO therapy consumed less oxygen than NP and FM therapy (NP 2.6[+ or -]1.0, NPO 2.2[+ or -]0.9, FM 6.1[+ or -]0.4 l/min, P <0.001). There was no significant difference in patients' respiratory rates (NP 19.9[+ or -]3.2, NPO 19.9[+ or -]3.0, FM 19.8[+ or -]3.1 per minute, P=0.491). In terms of comfort, patients rated NP higher than NPO and FM using a horizontal visual analogue scale (100 mm=most comfortable) (NP 65.5[+ or -]14.3, NPO 62.8[+ or -]19.4, FM 49.4[+ or -]21.4 mm, P <0.001). We conclude that for adult patients, nasal prongs and nasopharyngeal oxygen therapy consume less oxygen and provide greater comfort than facemasks while still maintaining Sp[O.sub.2] [greater than or equal to]95%.

Behavior of magnesium in Hank's solution aimed to trabecular pattern of natural bone

An ideal artificial bone is expected to grow together with other natural bones with aid of osteoblast cells and to fade out into other natural bones at the same rate of restructuring natural bone. Magnesium is thought to be one of candidate materials, since it has a potential to enhance natural bone growth and to homogenize the implanted artificial bodies with natural bone. In the present study, we are concerned with the formation of trabecular pattern in the natural bone to consider how to reconstruct this pattan in the artificial bone made from magnesium. For that purpose, a series of experiments were perfonned to observe the chemical behavior of dipped magnesium plate and cellular magnesium in Hank's solution. A magnesium specimen is annealed at 773 - 803 K for various periods in an atmosphere to homogenize its microstructure. Mass change of magnesium is estimated by immersing it in Hank's solution. It is well known that magnesium is easily corroded by chlorine ion. Both x-ray diffraction and energy dispersed x-ray analyses were carried out in order to identify a reaction product and its chemical composition. Mass of a magnesium specimen, which was annealed at 803 K for 32.4 ks or 14.4 ks, increases after immersing it into Hank's solution for 4.5 18 Ms (1255 h). Furthermore, the cellular magnesium, which was annealed at 803 K for 1.8 ks, fanned a reacted layer with around 80 μ in thickness and it contained Mg, Ca, P, and a little bit of CI.

Immobilization of large, aliovalent cations in the small-pore zeolite K-natrolite by means of pressure

High-pressure ion exchange of small-pore zeolite K-natrolite allows immobilization of nominally non-exchangeable aliovalent cations such as trivalent europium. A sample exchanged at 3.0(1) GPa and 250 °C contains about 4.7 Eu^III ions per unit cell, which is equivalent to over 90 % of the K⁺ cations being exchanged.