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Parkinson's disease (PD) is a progressive neuropathology characterized by motor and non-motor alterations. β-sitosterol β-d-glucoside (BSSG) is a neurotoxin whose prolonged oral administration in rats has been proposed as a new PD model. Herein, we demonstrate that a single, unilateral, and intranigral administration of BSSG also elicits bilateral sensorimotor alterations in the rat. Six behavioral tests evaluated the effect of different concentrations of BSSG (3, 6, 9, and 12 μg/μL DMSO) from 15 to 120 days after administration. The first behavioral alterations, which appeared on day 15, were unbalanced and uncoordinated gaits and a decrease in the sensorimotor cortex activity, as evidenced by the beam-walking and the vibrissae tests, respectively. After 30 days, the corridor test revealed hyposmia and a decreased locomotor activity in the open field. The last alteration was a depressive-like behavior, as shown by the forced swim test on days 60 and 120. According to the cylinder test, no locomotor asymmetry was observed over time with any BSSG concentrations tested. Also, a mesencephalic TH(+) cell loss (p 0.05) was shown on day 30 when compared with the mock condition, and such a loss was even higher on day 120. At this time, the presence of pathological α-synuclein aggregates in the mesencephalon was documented. Our results show that the stereotaxic intranigral administration of BSSG reproduces some characteristics of oral administration, such as the progression of behavioral alterations, dopaminergic neurons loss, and the presence of Lewy body-like synuclein aggregations, in less time and resources.

First measurements of double-polarization observables in ω photoproduction off the proton are presented using transverse target polarization and data from the CEBAF Large Acceptance Spectrometer (CLAS) FROST experiment at Jefferson Lab. The beam-target asymmetry F has been measured using circularly polarized, tagged photons in the energy range 1200-2700 MeV, and the beam-target asymmetries H and P have been measured using linearly polarized, tagged photons in the energy range 1200-2000 MeV. These measurements significantly increase the database on polarization observables. The results are included in two partial-wave analyses and reveal significant contributions from several nucleon (N^{*}) resonances. In particular, contributions from new N^{*} resonances listed in the Review of Particle Properties are observed, which aid in reaching the goal of mapping out the nucleon resonance spectrum.

In the past two decades, deeply virtual Compton scattering of electrons has been successfully used to advance our knowledge of the partonic structure of the free proton and investigate correlations between the transverse position and the longitudinal momentum of quarks inside the nucleon. Meanwhile, the structure of bound nucleons in nuclei has been studied in inclusive deep-inelastic lepton scattering experiments off nuclear targets, showing a significant difference in longitudinal momentum distribution of quarks inside the bound nucleon, known as the EMC effect. In this work, we report the first beam spin asymmetry (BSA) measurement of exclusive deeply virtual Compton scattering (DVCS) off a proton bound in $^4$He. The data used here were accumulated using a $6$ GeV longitudinally polarized electron beam incident on a pressurized $^4$He gaseous target placed within the CLAS spectrometer in Hall-B at the Thomas Jefferson National Accelerator Facility. The azimuthal angle ($\phi$) dependence of the BSA was studied in a wide range of virtual photon and scattered proton kinematics. The $Q^2$, $x_B$, and t dependencies of the BSA on the bound proton are compared with those on the free proton. In the whole kinematical region of our measurements, the BSA on the bound proton is smaller by 20\% to 40\%, indicating possible medium modification of its partonic structure.

Resumen: Actualmente, el crecimiento continuo en la demanda de cemento genera preocupaciones ambientales y de sostenibilidad en la industria cementera. Por otra parte, la generación de grandes cantidades de residuos sólidos urbanos a nivel mundial provoca daños en la salud humana y en la calidad del medio ambiente. Por lo anterior, esta investigación propone evaluar la sustitución parcial del cemento Portland por un polvo residual obtenido de la descomposición química de residuos orgánicos de origen vegetal o animal, tales como restos de alimentos (carne, vegetales, frutas, cáscara de huevo), papel, madera, huesos y semillas. De esta forma, una contribución científica podría generar un cambio consciente en el desarrollo de un producto como material alternativo que contribuya con procesos más sostenibles en la industria de la construcción. Se estudiaron tres tipos de mezcla, variando el contenido de cemento, seleccionando las proporciones agregados/cemento (a/c) de 15, 10 y 6. Se prepararon hormigones sustituyendo el cemento por el polvo de residuo orgánico, en peso, en porcentajes de 5, 10, 15 y 20%. Se evaluaron sus propiedades físicas y mecánicas. Los resultados mostraron que el hormigón de referencia presentó mayor resistencia a la compresión que el hormigón con bajo contenido de cemento (proporción a/c de 15:1). Sin embargo, las mezclas preparadas con un 5% de polvo y razón a/c de 10:1 presentaron valores de al menos 2,1% superiores a la resistencia a la compresión del hormigón de referencia. Las mezclas ricas en cemento (razón a/c de 6:1) con reemplazo de polvo de hasta un 10% mostraron un mejor desempeño mecánico, 13% superior, en relación al hormigón padrón. En consecuencia, se puede usar el polvo orgánico como material de relleno (filler) en el hormigón para sustituir parte del cemento puesto que se obtienen hormigones más resistentes y densos y con menor absorción específica e índice de vacíos.

Alzheimer’s disease (AD) is the most common neurodegenerative disease worldwide. Histopathologically, AD presents with two hallmarks: neurofibrillary tangles (NFTs), and aggregates of amyloid β peptide (Aβ) both in the brain parenchyma as neuritic plaques, and around blood vessels as cerebral amyloid angiopathy (CAA). According to the vascular hypothesis of AD, vascular risk factors can result in dysregulation of the neurovascular unit (NVU) and hypoxia. Hypoxia may reduce Aβ clearance from the brain and increase its production, leading to both parenchymal and vascular accumulation of Aβ. An increase in Aβ amplifies neuronal dysfunction, NFT formation, and accelerates neurodegeneration, resulting in dementia. In recent decades, therapeutic approaches have attempted to decrease the levels of abnormal Aβ or tau levels in the AD brain. However, several of these approaches have either been associated with an inappropriate immune response triggering inflammation, or have failed to improve cognition. Here, we review the pathogenesis and potential therapeutic targets associated with dysfunction of the NVU in AD.

The COMASA S.A. power plant is located near Temuco and burns a high amount of residual biomass produced in the Araucanía region. However, the main problem associated with this plant is the transportation and disposal of fly ash (9 tons per week), a residue generated during the combustion of Boiler I. Currently, fly ashes from Boiler I are transported more than 200 km south, increasing transportation and final disposal costs. In this study, the development of a mortar based on fly ash from the combustion of biomass from COMASA S.A. was analysed at a pre-feasibility level. The experimental procedure consisted of (i) the physicochemical characterization of biomass fly ash, (ii) obtaining different test specimens (mortars) via the addition of different proportions of fly ash (10-35%) to cement, and (iii) obtaining the best specimen by analysing the requirements of mortars for construction purposes (Chilean Standard NCh 1037). The test specimens were subjected to determination of apparent density, compression resistance, water absorption capacity and moisture content. The laboratory results showed that the mortar obtained with the addition of 20% of fly ash has similar physical characteristics to mortars used for building blocks, proving capable of resisting up to 20 MPa. To analyse the viability of the production of construction blocks based on best specimen, market, technical and economic-financial studies were carried out, considering the reuse of at least 60% of the fly ash generated per year. The study concluded that the project was viable, evidencing the potential use of this residue for the manufacture of low-cost blocks, while minimizing the cost associated with residue handling.

The barrel calorimeter is part of the new spectrometer installed in Hall D at Jefferson Lab for the GlueX experiment. The calorimeter was installed in 2013, commissioned in 2014 and has been operating routinely since early 2015. The detector configuration, associated Monte Carlo simulations, calibration and operational performance are described herein. The calorimeter records the time and energy deposited by charged and neutral particles created by a multi-GeV photon beam. It is constructed as a lead and scintillating-fiber calorimeter and read out with 3840 large-area silicon photomultiplier arrays. Particles impinge on the detector over a wide range of angles, from normal incidence at 90 degrees down to 11.5 degrees, which defines a geometry that is fairly unique among calorimeters. The response of the calorimeter has been measured during a running experiment and performs as expected for electromagnetic showers below 2.5 GeV. We characterize the performance of the BCAL using the energy resolution integrated over typical angular distributions for $\pi^0$ and $\eta$ production of $\sigma_E/E$=5.2\%/$\sqrt{E(\rm{GeV})} \oplus$ 3.6\% and a timing resolution of $\sigma$\,=\,150\,ps at 1\,GeV., Comment: 46 pages, 33 figures

We report measurements of the photon beam asymmetry Σ for the reactions γ - p→pπ0 and γ - p→pη from the GlueX experiment using a 9 GeV linearly polarized, tagged photon beam incident on a liquid hydrogen target in Jefferson Lab's Hall D. The asymmetries, measured as a function of the proton momentum transfer, possess greater precision than previous π0 measurements and are the first η measurements in this energy regime. The results are compared with theoretical predictions based on t-channel, quasiparticle exchange and constrain the axial-vector component of the neutral meson production mechanism in these models.

The novel Hamamatsu Multi Pixel Photon Counter Array S12045(X) is an array of 16 individual MPPCs (3×3 mm2) (further in the paper MPPC array channel) each with 3600 G-APD (Geiger-mode Avalanche Photodiodes) pixels (50×50 [ μ m 2 ]). Each MPPC in the array works with its individual reverse bias voltage mode (around 70 V). The paper summarizes the characterization process of MPPC arrays used in GlueX experiment (Hall D, Jefferson Lab). We studied the main features of each MPPC array channel for 2800 MPPC arrays at different temperatures. Two measurement stations were built to extract gain, breakdown voltage, photo detection efficiency (PDE), optical crosstalk and dark rate for each MPPC array channel. The hardware and the data analysis are described, which includes new analytical expressions to obtain the mean number of photo-electrons and optical crosstalk. The dynamical behavior of characterization parameters is presented as well.

Studies on hexose consumption by Saccharomyces cerevisiae show that glucose is consumed faster than fructose when both are present (9:1 fructose to glucose) in the medium during the fermentation of Agave. The objective of this work was to select strains of S. cerevisiae that consume fructose equal to or faster than glucose at high fructose concentrations by analyzing the influence of different glucose concentrations on the fructose consumption rate. The optimal growth conditions were determined by a kinetics assay using high performance liquid chromatography (HPLC) using 50 g of glucose and 50 g of fructose per liter of synthetic medium containing peptone and yeast extract. Using the same substrate concentrations, strain ITD-00185 was shown to have a higher reaction rate for fructose over glucose. At 75 g of fructose and 25 g of glucose per liter, strain ITD-00185 had a productivity of 1.02 gL(-1) h(-1) after 40 h and a fructose rate constant of 0.071 h(-1). It was observed that glucose concentration positively influences fructose consumption when present in a 3:1 ratio of fructose to glucose. Therefore, adapted strains at high fructose concentrations could be used as an alternative to traditional fermentation processes.

Yeasts used in fermentation processes are subject to different stress conditions, including low pH, high initial substrate concentration, accumulation of toxic compounds (e.g. ethanol), and temperature fluctuations. The fermentation of mescal is conducted under variable environmental conditions throughout the year. One of the most important environmental factors is temperature, as autumn and winter fermentations occur at low temperatures, but fermentation temperatures are much higher in summertime. The aim of this work was to compare the response of Saccharomyces cerevisiae strains isolated from agave fermentations to different stress conditions and two different medium culture one mimicking mezcal production, using agave must and other synthetic must development for analysis in wine industry. The strains isolated from agave were compared with a commercial strain used in wine elaboration, which exhibits good tolerance to the different stresses found in industrial fermentations. All strains grew in the presence of glucose and fructose irrespective of the sugar concentration, and low pH did not affect the formation of colonies. Differences in growth were observed among the strains at low temperature and high concentrations of ethanol. Only 28% of the tested strains exhibited good tolerance to high ethanol concentrations, a desirable trait for avoiding stuck fermentations. The strain ITD00185 was able to grow in alcoholic stress condition, consuming sugar and producing ethanol in agave must. This strain shows tolerance to the different stress conditions and may be a useful starter culture for agave fermentation, the potential of the native strains to be used to improve other industrial fermentation processes that involve low temperatures and high ethanol yields. Key words: Ethanol, tolerance, Mescal, native strains.

EFECTO DE LAS HORMONAS OXITOCINA Y PROSTAGLANDINA F2a DURANTE LA INSEMINACIÓN ARTIFICIAL SOBRE LA EFICIENCIA REPRODUCTIVA EN CERDAS

Denitrification was studied in anoxic batch cultures of a simulated fish processing wastewater at 37 r C and pH 7.5, using a denitrifying enrichment culture from fishery wastewater. Different initial nitrate to biomass ratios (So/Xo) were used: nitrate and biomass varied from 7.5 to 94.7 mg NO3-N l−1, and from 20 to 4300 mg volatile suspended solids l−1, respectively. The specific maximum denitrification rate (r m) and the cell yield (Y X / S) depended on the So/Xo ratio under anoxic conditions: r m increased from 1.2 to 1584 mg NO3-N g−1 VSS h−1 and Y X / S decreased from 42 to 0.03 mg VSS mg−1 NO3-N when So/Xo varied from 5.5 ⋅ 10− 3 to 9.3 mg NO3-N/mg VSS. Nomenclature CNO3 − N nitrate concentration, mg NO3-N l−1 K S saturation constant, mg NO3-N l−1 r m specific maximum denitrification rate, mg NO3-N g−1 VSS h−1 So initial substrate concentration, mg l−1 t time, h TOC total organic carbon VSS volatile suspended solids x biomass concentration, g VSS l−1 Xo initial biomass concentration, g VSS l−1 Y X/S substrate to biomass cell yield, mg VSS/mg N Greek symbols: μm maximum specific growth rate of the anoxic microbial population, 1 h−1

Mexico has long based its strength on the exploitation of its offshore fields to become one of the largest oil producers in the world. Although still yielding most of its production today, those mature fields have entered a downward trend for the past few years, with a gradual decline of their hydrocarbon output. This trend coincided with an increase in work over operations, most of them involving matrix acidizing interventions in carbonate formations for damage removal and stimulation purposes. Matrix stimulation of offshore Mexico fields presents several challenges, starting with the very nature of the carbonate rocks composing the reservoirs, whose properties can greatly vary within a short distance. In addition, the well conditions are also at times not well understood, with perforated intervals heterogeneously producing, and the increasing occurrence of water production. Finally, due to the location offshore, time-efficiency and operational simplicity became important workover requirements that have a direct impact on the chosen stimulation procedure, often achieved using a simple bullheading sequence, which unfortunately leaves the much needed control of zonal coverage out of the equation. This paper presents a carbonate acidizing workflow and interpretation method that have been developed and successfully implemented in offshore Mexico over the past couple of years. This technique constitutes the cornerstone to assessing and controlling matrix acidizing treatment coverage while it is pumped, in real-time, to ensure optimum treatment performance and maximum return on costs. The workflow relies on the use of a fiber-optic line enclosed inside a coiled tubing (CT) string to acquire distributed temperature sensing data, which are analyzed and translated into a zonal coverage profile using a fast interpretation algorithm. This information then allows stimulation engineers to determine the best strategy for the subsequent well stimulation treatment, including fluid volumes and placement sequence. As the case studies presented in this study will show, there is a lot to gain from this improved methodology. In particular, they show that the long-standing blind bullheading practice results in some shortcomings that may be detrimental to truly unlocking the full potential of those offshore fields.

The novel Hamamatsu Multi-Pixel Photon Counter (MPPC) S12045(X) is an array of 16 individual 3×3 mm 2 MPPC devices each with 3600 Geiger-mode Avalanche Photodiode pixels of 50×50 μm 2 . Each MPPC in the array operates at a reverse bias of approximately 70 V. This paper summarizes our characterization of MPPC arrays used in the GlueX experiment in Hall D at Thomas Jefferson National Accelerator Facility (Jefferson Lab). We studied the main features of each of the 16 MPPC array channels for 2800 MPPC arrays at several different temperatures. Two measurement stations were built to extract gain, breakdown voltage, photon detection efficiency, optical crosstalk and dark rate for each of the 44 800 MPPC array channels at each temperature setting. The hardware and the data analysis are described, and new analytical expressions for the mean number of photoelectrons and optical crosstalk are presented, as well as systematic trends of the performance parameters.

A retrospective evaluation of the clinical and radiographic results of the Harris-Galante acetabular cups was performed in 112 patients with 127 total hip arthroplasties. Patients with 14 hips had died, and patients with 20 hips were lost to follow-up. A total of 82 patients with 93 hips was available for follow-up. There were 67 men and 45 women. The mean follow-up was 87 months (range, 48–113 months). There were a total of 9 revisions: 2 for recurrent dislocations, 1 for a loose cup, and 6 for wear and osteolysis. Radiographic evaluation demonstrated that 22 (24%) hips had periacetabular osteolysis, and 16 of these 22 (73%) were associated with the screws. Twenty-two hips (23%) demonstrated osteolytic lesions around the femoral stem. Mean femoral head displacement was of 1.00 mm (range, 0.40–4.5 mm) with a rate of 0.16 mm/yr (range, 0.05–0.44 mm/yr). The Harris-Galante socket has maintained a low implant failure rate at intermediate term, even in these young patients. As follow-up increases, wear of the polyethylene and periprosthetic osteolysis may become growing concerns.

To further assess the clinically active dose range of etoricoxib, a COX-2 selective inhibitor, in rheumatoid arthritis (RA).RA patients were randomized to etoricoxib 10, 30, 60, or 90 mg or placebo in a double-blind, 12-week study. DMARDs (methotrexate, biologics) or low-dose corticosteroids were allowed in stable doses. The primary endpoint was the proportion of patients completing the study and achieving an American College of Rheumatology 20% (ACR20) response. Secondary endpoints included individual components of the ACR index and Patient Global Assessment of Pain. Safety was assessed by physical exam and adverse experiences (AEs) occurrences.Etoricoxib 90 mg was the only dose to reach a statistically significant difference from placebo (p 0.001) on the primary endpoint; etoricoxib 60 mg approached significance (p = 0.057). Significant pain improvement vs. placebo was observed with etoricoxib 90 mg (p 0.001), 60 mg (p = 0.018), and 30 mg (p = 0.017). Despite the use of background biologics and corticosteroids, a dose response was still apparent. A higher proportion of etoricoxib 60 and 90 mg patients had renovascular AEs (i.e., edema and hypertension) compared with placebo, although discontinuations for renovascular AEs were rare. Etoricoxib 90 mg had a higher incidence of serious AEs (n = 5; 1 was considered drug-related) versus placebo (n = 0).The present study was not powered to detect differences in cardiovascular or gastrointestinal safety by dose. Additionally, further research is needed to clarify the role of doses less than the etoricoxib 90 mg dose for pain management in RA patients.Etoricoxib 90 mg demonstrated statistically superior efficacy (ACR20) compared with placebo and numerical superiority over the other doses of etoricoxib studied. Etoricoxib 30 and 60 mg demonstrated significant pain improvement versus placebo, suggesting utility for some patients.

El estudio estuvo dirigido a determinar el efecto de los cuentos infantiles para promover el desarrollo de conceptos matemáticos en los niños del primer grado de educación primaria del Colegio Nacional de Aplicación UNHEVAL. Para tal efecto, se seleccionaron 15 niños como muestra y, al inicio de la parte aplicativa del trabajo de investigación, se les aplicó un pretest consistente en una prueba sobre nociones de conceptos matemáticos como: Nociones espaciales, El tiempo, el espacio, cuantificadores y numerales; con el fin de determinar los conocimientos de estos conceptos y como se iniciaban los niños. A continuación se procedió a desarrollar las actividades, que tuvieron una duración de un mes, y al final del cual se les volvió a aplicar el postest, consistente en la misma prueba. Los resultados a los que arribamos nos demostraron que la aplicación de los cuentos infantiles mejora el desarrollo de los conceptos matemáticos en los niños del primer grado de educación primaria.

Con el propósito de aprovechar un recurso que en la actualidad es un desecho contaminante generado durante el aserre de la madera en Durango, México, se probaron los métodos de pretratamiento alcalino, ácido y explosión con vapor a temperatura de autoclave, para realizar la hidrólisis enzimática de aserrín de pino obtenido de tres aserraderos de la ciudad de Durango y recuperar los azúcares contenidos en él. Se encontró que el pretratamiento con NaOH a 120 ºC proporciona mejores resultados que los tratamientos con ácido sulfúrico diluido y por explosión con vapor a 121 ºC. Se optimizó el pretratamiento alcalino por el método de superficie de respuesta. Los resultados muestran que la concentración óptima de azúcares reductores, con un valor de 48 %, se obtuvo después de un pretratamiento con 8 % de NaOH durante 85 minutos a 120 ºC, a un pH de hidrólisis de 4.5, durante 240 h, con una carga enzimática de 25 UPF/g de carbohidratos totales. Por comparación con los resultados reportados en la literatura, se encuentra que el procedimiento obtenido es susceptible de ser utilizado para el aprovechamiento de este recurso.

The human evolutionary model is an intelligent global optimization method conceived to perform single and multiple objective optimization, this general method is still in development, especially the multi objective (MO) part is being improved. The single objective (SO) part has demonstrated that outperforms several algorithms that are in the state of the art, for example differential evolution (DE), particle swarm optimizer, and others, we called this part single objective intelligent evolutionary algorithm (SO-IEA). The SO-IEA uses mediative fuzzy logic (MFL) for handling doubtful and contradictory information from experts to calculate the appropriated amount of individuals to create and/or to eliminate. MFL is an extension of traditional fuzzy logic and includes intuitionistic fuzzy logic (IFL) in the Atanassov sense. In this work, we are presenting the algorithm's architecture, experimental results, and a graphical interface that will help to handle the required parameters to use the SO-IEA.

Heap leaching is an effective and widely used method of recovering metals from low-grade ores. However, the heap leaching technique has not yet been used in other biotechnological processes such as bioremediation. This work describes biostimulation of the native microbial consortium as a novel application of the heap leaching technique to bioremediate mining soils contaminated with hydrocarbons. Microorganisms present in the polluted soil were isolated in a liquid mineral solution using diesel fuel as the sole energy and carbon source. Biodegradation activity was evaluated and two genera, Flavobacterium and Aspergillus , were identified as the primary microorganisms that degraded hydrocarbons in the polluted soil. In order to simulate the heap leaching process on a laboratory scale, using both columns and piles, the contaminated soil was mixed with different sand concentrations and was agglomerated before it was used. Three flow rates, of the mineral solution, were evaluated. Of the rates tested, biodegradation was most efficient at a flow rate of 200 ml h −1 . The heap leaching technique demonstrated good efficiency in the column and pile, with a 2% soil–sand mixture lowering the TPH concentration from 61,000 to 1800 mg kg −1 (98.5%) in 15 d.

The neurovascular bundle anatomy in the upper arm displays changing relationships of nerve and vascular structures along short segments. Fibrous tissues segregate these elements into enclosed compartments allowing for specific patterns of injury. We report a patient with a iatrogenic brachial artery injury in this region who featured combined median and MAC neuropathies, which were consistent with complete axonotmesis on neurophysiological assessment. Increased intracompartmental pressure may have led to nerve injury either thorough an ischemic mechanism or to focal compression. Recognition of this unusual pattern of nerve damage is important, since injury can be accurately localized to the midportion of the neurovascular compartment in the upper arm.

Two design methodologies based on Incomplete-Gradient adjoint approaches for flow problems governed by the incompressible Navier-Stokes (NS) equations are presented. The main features of the algorithms is that they avoid solving the adjoint equations, saving an important amount of CPU time. Furthermore, the methodologies are general in the sense that they do not depend on the geometry representation, and all the gridpoints on the surface to be optimized can be chosen as design parameters. The partial derivatives of the flow equations with respect to the design parameters are computed by finite differences. In this way, this computation is independent of the numerical scheme employed to obtain the flow solution and the type of mesh. Once the sensitivities and the direction of movement have been computed, the new solid surface is obtained with a pseudo-shell approach in such a way that local singularities, which can degrade or inhibit the convergence to the optimal solution, are avoided. Furthermore, this surface parametrization allows to impose the problem geometrical restrictions in a very easy manner. The volume mesh is updated to fix the new boundary using an innovative level approach, which allows to compute the sensitivity contribution of the interior mesh points by using finite differences in a very fast manner. The methodologies can deal with multi-objective function problems, and flow restrictions such as constant lift, etc. Some 2D and 3D numerical examples are shown.

A retrospective evaluation of the clinical and radiographic results of the Harris-Galante acetabular cups was performed in 112 patients with 127 total hip arthroplasties. Patients with 14 hips had died, and patients with 20 hips were lost to follow-up. A total of 82 patients with 93 hips was available for follow-up. There were 67 men and 45 women. The mean follow-up was 87 months (range, 48-113 months). There were a total of 9 revisions: 2 for recurrent dislocations, 1 for a loose cup, and 6 for wear and osteolysis. Radiographic evaluation demonstrated that 22 (24%) hips had periacetabular osteolysis, and 16 of these 22 (73%) were associated with the screws. Twenty-two hips (23%) demonstrated osteolytic lesions around the femoral stem. Mean femoral head displacement was of 1.00 mm (range, 0.40-4.5 mm) with a rate of 0.16 mm/yr (range, 0.05-0.44 mm/yr). The Harris-Galante socket has maintained a low implant failure rate at intermediate term, even in these young patients. As follow-up increases, wear of the polyethylene and periprosthetic osteolysis may become growing concerns.

Objective: To evaluate the sensitivity of transcranial magnetic stimulation (TMS) to identify upper motor neuron involvement in patients with motor neuron disease. Background: Diagnosis of ALS depends on upper and lower motor neuron involvement. Lower motor neuron involvement may be documented with electromyography, whereas definite evidence of upper motor neuron involvement may be elusive. A sensitive, noninvasive test of upper motor neuron function would be useful. Methods: TMS and clinical assessment in 121 patients with motor neuron disease. Results: TMS revealed evidence of upper motor neuron dysfunction in 84 of 121 (69%) patients, including 30 of 40 (75%) patients with only probable upper motor neuron signs and unsuspected upper motor neuron involvement in 6 of 22 (27%) patients who had purely lower motor neuron syndromes clinically. In selected cases, upper motor neuron involvement identified with TMS was verified in postmortem examination. Increased motor evoked potential threshold was the abnormality observed most frequently and was only weakly related to peripheral compound muscle action potential amplitude. In a subset of 12 patients reexamined after 11 ± 6 months, TMS showed progression of abnormalities, including progressive inexcitability of central motor pathways and loss of the normal inhibitory cortical stimulation silent period. Conclusions: TMS provides a sensitive means for the assessment and monitoring of excitatory and inhibitory upper motor neuron function in motor neuron disease.

Four newborn patients with symptomatic Chiari II malformations were studied retrospectively. Clinical manifestations and surgical results are presented. All of these patients had hydrocephalus, which was symptomatic in two patients from the first day of life. Three of them had bradycardia and apnea spells. Two patients had lower cranial nerve palsies. Cranial sonography was the first neuroimaging procedure used and it played an important role during the follow-up period, especially for the study of the hydrocephalus. Two newborns could be studied with Magnetic Resonance Imaging (MRI). It defined the level of the decent of the fossa posterior structures and the associated malformations. All of the patients were treated with surgical repair of the spinal dysraphism, ventricular shunt and decompressive surgery. Two patients died before the age of three months. Two other patients showed better evolution after their two year and four year check-ups, respectively. Bradycardia and apnea spells are features that worsen the prognosis as compared with other manifestations.

Reports on supratentorial metastases of medulloblastoma are infrequent. Computed tomography has increased the possibilities of detecting then in a silent clinical phase. Five children with supratentorial metastasis of medulloblastoma were retrospectively reviewed. Diagnosis was established by cranial CT between three and sixty months following treatment of the tumor. Dissemination through the ventricular system was found in all the cases. Other lesions were found in the transition zone between the white and grey matter (2/5) and the left frontal lobe (1/5). The routes of dissemination are discussed. Early diagnosis of supratentorial metastasis of medulloblastoma require periodic cranial CT or magnetic resonance imaging (MRI), at least during the first years after diagnosis and treatment of the primary tumor.

Neuroleptic malignant syndrome (NMS) is an adverse reaction of an idiosyncratic nature to drugs having antidopaminergic activity. Pathogenesis is largely disputed. An NMS case is presented which was triggered by flupentixol and was associated with severe hyponatremia (116 mmol/l upon admission). Both clinically and analytically, the hyponatraemia fulfills criteria to be considered secondary to an inappropriate secretion of antidiuretic hormone (SIADH). Other possible causes of hyponatraemia were ruled out. After early treatment with dopaminergic agonists and water restriction, both conditions improved in parallel. The different pathogenetic possibilities which may explain the temporal coexistence of both syndromes in the same patient are discussed. The association of these two conditions is in favour of a probable central pathogenetic cause for NMS. On the other hand, it is suggested that hyponatraemia may mask the diagnosis of NMS.

Background: Motor preparation is associated with excitability changes along the corticospinal tract. In simple reaction time task (SRT), the motor-evoked potentials (MEP) to transcranial magnetic stimulation (TMS) are facilitated before onset of EMGactivity (EMGonset), and the short-latency intracortical inhibition (SICI) is reduced preceding the facilitatory changes.We examined the timing of those neural processes in choice reaction time task (CRT). Aim: To identify potential differences in SICI during SRT and CRT paradigms. Patients/Methods: Five subjects were requested to perform a hand pinch in response to a visual stimulus in the context of SRT/CRT paradigms. MEPs were recorded from the first dorsal interosseous. TMS was applied over the contralateral hand area at an intensity of 0.95 active motor threshold for conditioning stimuli and 1.2 resting motor threshold for test stimuli. We obtained sets of responses combining single and paired (interstimulus interval 2.5 ms) stimuli with control and movement trials. Test stimuli were applied at 100, 75, 50 and 25 ms with respect to EMGonset. We used ANOVA to determine the differences between control and test trials. Results: During SRT, significant reduction of SICI with respect to baseline values occurred at 50 ms before EMGonset, while MEP facilitation started 25 ms later. Reduction of SICI occurred significantly later during CRT than during SRT (p 0.05). Discussion: The time course of intracortical excitability changes before EMGonset is different in SRT and CRT. In SRT, with direct stimulus/response mapping, SICI reduction precedes MEP facilitation. In CRT, characterized by uncertain stimulus/response mapping, reduction of SICI and MEP facilitation occur in parallel. Conclusion: The timing of premovement modulation of SICI with respect to MEP facilitation before EMGonset depends on the behavioral context.