Use of liver grafts from cadaveric donors: Implementation impact of a local evaluation and procurement team in Mexico.

INTRODUCTION AND AIMS: Cadaveric donor liver graft retrieval is complex in Mexico. The aim of the present article was to present the experience in liver graft use during the first year of work of a local evaluation and procurement team. MATERIALS AND METHODS: We reviewed the organ donation report forms and allocation offer records covering the time frame of December 15, 2017 to December 15, 2018, and registered the donor characteristics, causes of organ discard, causes of declined offers, transport time, and graft and recipient survival at 30 days. RESULTS: There were 17 donations and we completed the evaluation of 14. Two donors were considered ideal (14.2%) and 12 were expanded criteria donors (ECDs) (85.7%). Two grafts with steatosis were not offered (14.2%). Twelve liver grafts were offered 88 times (mean 7.6 offers per graft). The acceptance rate was 6% for public hospitals and 23.6% for private hospitals (p = 0.016). One graft was discarded during the procurement process due to steatosis. The rate of use after evaluation was 78.5% (11/14). All the grafts were procured by the local team and 9 (81.8%) were transported by commercial airline (median 240 min, range 85 min). Graft and recipient survival at 30 days was 100%. CONCLUSIONS: The participation of a local evaluation and procurement team notably increased liver graft use with excellent results. Commercial airline transportation of the grafts to all active transplantation centers of the country resulted in cold ischemia times <6 h.

Training needs detected by nurses in an intensive care unit: a phenomenological study. / Necesidades de formación detectadas por enfermeras de una unidad de cuidados intensivos: un estudio fenomenológico.

INTRODUCTION: The competences of intensive care (ICU) nurses in their healthcare environment, have increased with the acquisition of new responsibilities associated with new care and devices for critical patients. Many studies suggest the need for specific training of nurses that work in these units. Based on this evidence, the European Federation of Critical Care Nurses Associations, recommends unifying the training of intensive care nurses. Therefore we set ourselves the following objective: to assess the training needs detected by ICU nurses through their experience and practical knowledge. METHOD: Descriptive qualitative study, with a phenomenological approach, through semi-structured interview where the four areas (clinical practice, professional, management and educational) covered by the European Federation of Critical Care Nurses Associations were studied. Fifteen nurses from an adult polyvalent ICU were interviewed. RESULTS: The interviewees acknowledged that the previous training was deficient for the care and support measures that they had to face. They considered that subsequent training and experience were decisive in order to carry out their work effectively. They also stated that support measures and care are topics to be developed continuously through targeted training. CONCLUSION: The nurses in this research study acknowledged that training is needed to achieve the competences required in ICU, and these are affected by the type of unit and patients.

Influence of averaging method on muscle deoxygenation interpretation during repeated-sprint exercise.

Near-infrared spectroscopy (NIRS) is a common tool used to study oxygen availability and utilization during repeated-sprint exercise. However, there are inconsistent methods of smoothing and determining peaks and nadirs from the NIRS signal, which make interpretation and comparisons between studies difficult. To examine the effects of averaging method on deoxyhaemoglobin concentration ([HHb]) trends, nine males performed ten 10-s sprints, with 30 seconds of recovery, and six analysis methods were used for determining peaks and nadirs in the [HHb] signal. First, means were calculated over predetermined windows in the last 5 and 2 seconds of each sprint and recovery period. Second, moving 5-seconds and 2-seconds averages were also applied, and peaks/nadirs were determined for each 40-seconds sprint/recovery cycle. Third, a Butterworth filter was used to smooth the signal, and the resulting signal output was used to determine peaks and nadirs from predetermined time points and a rolling approach. Correlation and residual analysis showed that the Butterworth filter attenuated the "noise" in the signal, while maintaining the integrity of the raw data (r = .9892; mean standardized residual -9.71 × 103  ± 3.80). Means derived from predetermined windows, irrespective of length and data smoothing, underestimated the magnitude of peak and nadir [HHb] compared to a rolling mean approach. Consequently, sprint-induced metabolic changes (inferred from Δ[HHb]) were underestimated. Based on these results, we suggest using a digital filter to smooth NIRS data, rather than an arithmetic mean, and a rolling approach to determine peaks and nadirs for accurate interpretation of muscle oxygenation trends.

Radiating subdispersive fractional optical solitons.

It was recently found [Fujioka et al., Phys. Lett. A 374, 1126 (2010)] that the propagation of solitary waves can be described by a fractional extension of the nonlinear Schrödinger (NLS) equation which involves a temporal fractional derivative (TFD) of order α > 2. In the present paper, we show that there is also another fractional extension of the NLS equation which contains a TFD with α < 2, and in this case, the new equation describes the propagation of radiating solitons. We show that the emission of the radiation (when α < 2) is explained by resonances at various frequencies between the pulses and the linear modes of the system. It is found that the new fractional NLS equation can be derived from a suitable Lagrangian density, and a fractional Noether's theorem can be applied to it, thus predicting the conservation of the Hamiltonian, momentum and energy.

Evaluación del estado psicobiotipológico en bomberos: parámetros de salud y recursos anti estrés / Assessment of biopsycho typological state of firefighters: health parameters and anti stress resources

La morfoestructura y características psicológicas de los bomberos cobran vital importancia, ya que deben poseer un rendimiento físico y psicológico de alto nivel, para afrontar los requerimientos propios de su labor. Es fundamental conocer el Biotipo, así como también, la personalidad resistente y el nivel de Síndrome Burnout presente en esta población, evaluando el perfil de voluntarios activos de las comunas de Valparaíso y Viña del Mar. Se estudiaron 101 voluntarios de sexo masculino, con edades entre los 20 y 50 años, de las compañías de Valparaíso y Viña del Mar. Se aplicó el método de somatotipo de Heath ­ Carter, personalidad resistente y el nivel de Síndrome Burnout guiados por la metodología de Moreno Jiménez. Los resultados indican un Somatotipo predominantemente como endomesomórfico, endomorfía 5,44±1,60; Mesomorfía 6,17±1,37; ectomorfía 0,90±1,23. La personalidad resistente se encuentra con una calificación alta, Compromiso 3,61±0,39; Reto 3,53±0,47; Control 3,41±0,42, presentando el control una categoría media según DE. El Síndrome Burnout presenta una calificación baja para Factores 15,38±4,17; Síndrome 18,79±4,10; Consecuencias 5,64±1,98. Se destaca un alto componente Endomórfico, lo que traería consigo un riesgo cardiovascular. El perímetro de pierna está relacionado inversamente con la dimensión Control de Personalidad resistente, lo que indica que a mayor perímetro menor puntuación en control, disminuyendo la resistencia al Síndrome Burnout. Esta población no deportista, voluntaria y altruista, sin una actividad física programada, constante y periodizada, se ve reflejada en sus características antropométricas.

The morphostructural analysis and psychological characteristics of firefighters are vital; specific physical and psychological levels are needed to meet the requirements of their work. It is essential to know biotype, personality resistance variables and level of burnout syndrome present in this population. We evaluated the profile of active volunteers in the cities of Valparaiso and Viña del Mar in Chile; 101 male volunteers, aged between 20 and 50 years were included in the study. Heath ­ Carter somatotype, Personality Resistance variables and level of Burnout Syndrome according to Jiménez Moreno methodology were applied. The results indicate a predominant somatotype as Endomesomorph, Endomorph 5.44±1.60; Mesomorph 6.17±1.37, Ectomorph 0.90±1.23. Personality resistance variable presented a high score, commitment 3.61±0.39, challenge 3.53±0.47, control 3.41±0.42. Burnout syndrome had a low factor rating 15.38±4.17, syndrome 18.79±4.10; consequences 5.64±1.98. There is a high endomorphic component increasing cardiovascular risk. Leg circumference is on the other hand, related to Personality resistance control, indicating that while perimeter is greater, the mark is lower for Burnout resistance syndrome. The lack of continuous and programmed physical activity in this population of volunteer firefighters is clearly reflected in their anthropometric characteristics.

Validación del segundo paso de la escalera analgésica de la OMS: ¿es necesario el uso de opioides débiles? / No disponible

Objetivo: Comparar la eficacia, seguridad y tiempo hasta el alivio del dolor por cancer con acetaminofen solo versus acetaminofen mas codeina con el fin de analizar si es necesario el segundo paso de la escalera analgesica de la OMS. Métodos: Se realizo un ensayo clinico controlado, aleatorizado, doble ciego en mayores de 18 anos, con dolor por cancer de intensidad moderada o severa y Karnofsky >= 50/100. Se excluyeron pacientes con antecedentes de drogadiccion, insuficiencia renal o hepatica y embarazo. Se dividieron en dos grupos, uno tratado con acetaminofen y otro con acetaminofen mas codeina. Se realizo una evaluacion inicial y controles diarios durante 7 dias, evaluando analgesia, tiempo hasta el alivio del dolor y efectos colaterales. Se utilizaron las pruebas Chi cuadrado y Fisher para comparar proporciones, T y ANOVA para promedios. La comparacion del tiempo en lograr alivio se realizo mediante una curva de Kaplan-Meier. Resultados: Se asignaron veinte pacientes al grupo de acetaminofen y 16 al de acetaminofen mas codeina. No se presentaron diferencias estadisticamente significativas en la eficacia de los dos tratamientos. El tiempo transcurrido entre la primera dosis y el alivio fue 41 minutos para acetaminofen y 34 minutos para codeina mas acetaminofen (p > 0,05). El grupo de codeina presento mas estrenimiento (p = 0,001). Conclusión: No se presentaron diferencias significativas en eficacia y tiempo hasta el alivio del dolor. El grupo de codeína presentó más estreñimiento que el de acetaminofén (AU)

Objective: Compare the analgesic efficacy and tolerability of acetaminophen versus acetaminophen plus codeine in the relief of cancer-related pain. Methods: This 7-day, prospective, double-blind, randomized, parallel-group study was conducted with 36 patients with cancer pain. Outpatients were eligible for the study if they were aged >= 18 years and had moderate to severe cancer-related pain. Eligible patients were randomly assigned to receive acetaminophen or acetaminophen plus codeine. The primary end point was the proportion of patients who achieved pain relief; the second end point was time to achieve relief pain. Results: Of the 36 patients who participated, 20 received acetaminophen and 16 acetaminophen plus codeine. At baseline there were not differences between the groups. None of the between-group differences in response rates were significant (p > 0,05). The most common adverse effect in codeine group was constipation (p = 0,001). Conclusion: Efficacy was comparable between acetaminophen and acetaminophen plus codeine over 7 days of treatment in this patients with moderate or severe cancer-related pain. Codeine was associated with significantly greater constipation (AU)

Fractional fluctuation effects on the light scattered by a viscoelastic suspension.

We generalize fluctuating hydrodynamics to study the effect of fractional time derivatives on the light-scattering spectrum of a suspension in a viscoelastic solvent under an external density gradient. Viscoelasticity introduces additional memory effects into the fluctuating hydrodynamic equations, causing the time scales associated with the mesoscopic variables and those of the microscopic events to be no longer well separated. This situation is taken into account by introducing Caputo's fractional time derivative into the description. The structure factor of the suspension is calculated, and we find that its nonequilibrium correction is an odd function of the frequency. It exhibits a shift towards negative frequencies proportional to the magnitude of the imposed gradient. We consider solvents that are described by Maxwell's or power-law rheological equations of state. The fractional structure factor is compared with the nonfractional one, and it is found that the ratio of the former to the latter may be positive and up to two orders of magnitude for both types of viscoelasticity. This prediction of our model calculation suggests that this relative change might be measurable.

Symmetry breaking in linearly coupled Korteweg-de Vries systems.

We consider solitons in a system of linearly coupled Korteweg-de Vries (KdV) equations, which model two-layer settings in various physical media. We demonstrate that traveling symmetric solitons with identical components are stable at velocities lower than a certain threshold value. Above the threshold, which is found exactly, the symmetric modes are unstable against spontaneous symmetry breaking, which gives rise to stable asymmetric solitons. The shape of the asymmetric solitons is found by means of a variational approximation and in the numerical form. Simulations of the evolution of an unstable symmetric soliton sometimes produce its breakup into two different asymmetric modes. Collisions between moving stable solitons, symmetric and asymmetric ones, are studied numerically, featuring noteworthy features. In particular, collisions between asymmetric solitons with identical polarities are always elastic, while in the case of opposite polarities the collision leads to a switch of the polarities of both solitons. Three-soliton collisions are studied too, featuring quite complex interaction scenarios.

Predicción de porcentaje de masa adiposa a través de impedancia bio-eléctrica y método antropométrico / Mass adipose prediction percentage through biolectrical impedance and anthropometric method

Este estudio fue desarrollado con la finalidad de formular una ecuación de predicción de % de masa adiposa en valores antropométricos, a partir, de los valores predeterminados a través del instrumento de bioimpedancia TANITA. Esto basado en la premisa de que cada día ha aumentado la importancia sobre la estimación de la masa adiposa a nivel clínico, por lo cual se evaluó una población de 28 sujetos cuyo rango de edad fluctúa entre los 20-28 años, pertenecientes a la Escuela de Caballería Blindada de la ciudad de Quillota. Se realizaron las mediciones pertinentes para la estimación de masa adiposa a través de la bioimpedancia y la antropometría, cuyos resultados arrojaron diferencias significativas entre ambos métodos, obteniendo un coeficiente de correlación de Pearson de 0,34. Esto nos indica que al evaluar los criterios de homocedasticidad, linealidad, para generar una ecuación de estimación, no sería posible...

This case was developed with the objective of makes a prediction equation of adipose mass percent in values anthropometric, to star off the predetermined slant of instruments of impedance bioelectric TANITA. This is based in the premise that every day the importance of estimation about the fat mass in a clinic level, it is getting bigger and bigger, for this reason a population of twenty eight people with age range fluctuate among twenty to twenty eight was evaluated, they were part of "Escuela de Caballería Blindada" in the city of Quillota. The Pertinent measurements for the estimation of fatty mass were realized through of impedance bioelectric and anthropometry, the results made big differences between both methods, obtaining an index of correlation coefficient a 0.13 and a person correlation of 0.34. This suggests that possible creation does not accomplish with the criteria homescedasticity, in brief, this is unsafe...

Chaotic solitons in the quadratic-cubic nonlinear Schrödinger equation under nonlinearity management.

We analyze the response of rational and regular (hyperbolic-secant) soliton solutions of an extended nonlinear Schrödinger equation (NLSE) which includes an additional self-defocusing quadratic term, to periodic modulations of the coefficient in front of this term. Using the variational approximation (VA) with rational and hyperbolic trial functions, we transform this NLSE into Hamiltonian dynamical systems which give rise to chaotic solutions. The presence of chaos in the variational solutions is corroborated by calculating their power spectra and the correlation dimension of the Poincaré maps. This chaotic behavior (predicted by the VA) is not observed in the direct numerical solutions of the NLSE when rational initial conditions are used. The solitary-wave solutions generated by these initial conditions gradually decay under the action of the nonlinearity management. On the contrary, the solutions of the NLSE with exponentially localized initial conditions are robust solitary-waves with oscillations consistent with a chaotic or a complex quasiperiodic behavior.

Comparación entre dos métodos utilizados para medir la curva lumbar / Comparison of two method for measuring the lumbar curve

Las alteraciones posturales tales como hiperlordosis, aumento de la cifosis, cifolordosis y escoliosis en columna, producen complicaciones a nivel músculo-esquelético y articular. Debido a esto, es que en el último tiempo ha aumentado el número de atenciones kinésicas por patologías de la columna lumbar, he aquí la importancia de un test clínico que cuente con la confiabilidad necesaria para determinar la curvatura lumbar. El objetivo de este estudio es determinar si existen diferencias en los resultados entre los dos métodos utilizados para medir la curva lumbar: el test clínico de las flechas sagitales y el ángulo de la columna lumbar mediante radiografías. En una muestra de 32 pacientes de edad promedio 44,93 (+/- 12,67 años) evaluados en el Servicio de Kinesiología del Centro Médico Megasalud de Viña del Mar entre los meses de Marzo y Agosto del 2008. El procedimiento utilizado fue el examen clínico, en el cual se usó una plomada que va desde C7, pasando por la línea ínterglútea. En el plano sagital se mide la curvatura lumbar a nivel de L3. Para la medición del ángulo de la curvatura lumbar se utilizó una radiografía proyección lateral en la cual se proyectan las mesetas superior de L1 e inferior de L5 para la conformación del ángulo lumbar y su posterior medición. El resultado obtenido por medio del examen clínico entre el test de las flechas sagitales y las radiografías del ángulo de la lordosis lumbar para un índice de concordancia de Kappa, fue mayor o igual a un 95 por ciento. De esta manera, se obtuvo que el test de las flechas sagitales es una herramienta válida para la pesquisa de patologías lumbares, al igual que la radiografía, con una marcada diferencia en el costo económico entre ambas.

The altered posture, such as hiperlordosis, increase in kyphosis, and scoliosis in cifolordosis column complications occur at the muscular, skeletal and articulate. Because of this, is that in recent times to increase the number of benefits for kinesics pathologies of the lumbar spine, and here the importance of a clinical test that has the confidence necessary to determine lumbar curvature. The objective of the study seeks to determine whether there are differences in outcomes between the two methods used to measure the lumbar curve, the test of the arrows sagitales and the angle of the lumbar spine using x-rays in patients greater than or equal to 21 years, as assessed the service kinesiology of Centro Médico Megasalud of Viña del Mar, between the months of March and August 2008. The procedure used was by means of physical examination, which uses a plumb line that runs from C7 through inter gluteal line in the sagittal plane was measured at the lumbar curvature of L3 and compared with the measurement of the angle curvature of the lumbar measured by radiographic position in bipedal in a side view in 32 adults, measures of kinesiology at the service of the Medical Center Megasalud of Viña del Mar, Chile. The result obtained by means of physical examination between the test of the arrows sagitales versus the angle of the lumbar lordosis measured by X-rays, reached a record of correlation between the two diagnostic tests greater than or equal to 95 percent. In conclusion we can say that the test of the arrows sagitales is a valid tool for the investigation of lumbar pathologies, like radiography, with a marked difference in cost between the two.

Hipertensión severa y taquicardia por bloqueo del ganglio estrellado: a propósito de un caso / Severe hypertension and tachycardia after a stellate blockage: a case report

El bloqueo de ganglio estrellado es un procedimiento frecuentemente utilizado para aliviar los dolores crónicos del miembro superior, cabeza y cuello. Las complicaciones de este procedimiento son poco frecuentes y de presentarse suelen ser leves y tener una corta duración; entre las más comunes están la ronquera temporal y hematomas. Debido a que el ganglio estrellado se encuentra anatómicamente cerca de estructuras importantes como los nervios frénicos, larínge o recurrente, vago y grandes arterias, la distribución del anestésico aplicado pueden afectar más de una estructura. A continuación se describe el caso clínico de una mujer de 39años con síndrome doloroso regional complejo (SDRC) en su extremidad superior derecha. Se le realizó un bloqueo de ganglio estrellado con 10 ml de procaína al 1 % sin epinefrina y minutos después presentó taquicardia e hipertensión severas, la presión arterial incrementó de 135/80 a 235/135 mmHg. Se han descrito en la literatura pocos casos de hipertensión severa y taquicardia después de un bloqueo de ganglio estrellado. El anestésico local utilizado pudo haberse diseminado hacia las estructuras del cuello cercanas al ganglio, las cuales juegan un papel importante en el mantenimiento de la presión arterial, tales como el seno carotideo, el nervio glosofaríngeo y el vago; el bloqueo pudo haber producido una actividad simpática sin oposición (AU)

Stellate Ganglion Block is a procedure frequently used toalleviate chronic pain from the upper limb, head and neck. Complications of this procedure are uncommon but when they occur generally have a mild severity and short duration. The most reported complications are: temporal dysphony and hematomas. Because the stellate ganglion is near important structures of the neck; such as the phrenic, laryngeal and vagusnerves and big arteries, the distribution of local anesthetic can affect one or more of these structures. We describe the clinical case of a 39 years old woman with complex regional pain syndrome in the left upper limb. A stellate ganglion block was perform with 10 ml of procaine 1% without epinephrine, some minutes later she develops a severe hypertension and tachycardia, the arterial pressure of the patient increased from135/80 to 235/135 mm Hg. Few cases of severe hypertension and tachycardia after stellate ganglion block have been reported in literature. The anesthetic may have disseminated to structures in the neck that play an important function in the maintenance of the arterial pressure, such as the carotid sinus and glossopharyngeal and vagus nerves. The blockage may have produced an unopposed sympathetic activity (AU)

Comparación de la eficacia analgésica de codeína más paracetamol vs tramadol en el tratamiento del dolor por cáncer / Comparison of the analgesic effectiveness of codeine plus paracetamol vs tramadol in the treatment of cáncer pain

Pain is the principal symptom in 70% of patients with severe cáncer. Analgesics therapy with a proper management controls pain in 80-90% of patients. Objective. Compare the analgesic efficacy and tolerability of codeine plus acetaminophen (CA) and tramadol clorhydrate (T) in the relief of cáncer pain. Method. A double blind, randomize controlled clinical trial was perform in patients with modérate to severe pain intensity. Randomly patients were assigned in a group for receiving codeine plus acetaminophen and in other group for receiving tramadol chlorhydrate for a three weeks period. Pain intensity was measure using a numeric scale from zero to ten in which modérate pain goes from 5-7, and severe pain goes from 8-10. Analgesic treatment was considered to be effective when pain disappear or become mild, 1-4 in the numeric scale. Results. One hundred fifteen patients participated, 59 receive CA and 56 T. In the group of patients that receive CA, 58% achieved pain relief with the initial dose of 150 mg/d and 8% responded to the double dose; 34% didn't experience pain relief. In the group patients treated with T pain relief occurred in 62% of patients with the initial dose of 200mg/d and 11% with the double dose; 27% didn't experienced pain relief. Differences between both groups were not significant in the analgesic efficacy. The tramadol group experienced in a significant way a higher incidence of adverse events of mild intensity: nausea (p: 0.05, RR: 0.62; IC95%: 0.38-1.01), dizziness (p: 0.04; RR: 0.58; IC95%: 0.33-1.01) and lost of appetite (p: 0.001; RR: 0.08; IC95%: 0.01-0.59). Conclusion. Efficacy of C and T during a treatment of 23 days was similar, no statistical differences were found. There were no differences in the analgesic effectiveness between CA and T in the management of cáncer pain. With the use of T a higher incidence of adverse events of mild intensity were reported (AU)

El dolor es el síntoma más importante en 70% de pacientes que padecen cáncer avanzado. La terapia con analgésicos utilizada en forma adecuada, controla el dolor en 80-90% de los pacientes. Objetivos. Comparar la eficacia analgésica y seguridad de la codeína más acetaminofén (CA) y Clorhidrato de Tramadol (T) en el alivio del dolor por cáncer. Método. Se realizó un ensayo clínico controlado doble ciego, en pacientes con dolor por cáncer de intensidad moderada o severa. En forma aleatoria se asignó un grupo de pacientes para ser tratados con la combinación de Codeína más paracetamol, mientras que el otro grupo recibió Clorhidrato de Tramadol por un periodo de tres semanas. La intensidad del dolor fue medida con una escala numérica de cero a diez, considerándose como dolor de intensidad moderada el marcado en la escala entre 5-7 y de intensidad severa de 8-10. El tratamiento analgésico se consideró eficaz cuando el dolor desapareció o disminuyó a una intensidad leve, comprendida entre 1-4. Resultados. Se incluyeron 115 pacientes: 59 recibieron CA y 56 recibieron T. En el grupo de pacientes que recibió CA 58% aliviaron con una dosis inicial de codeína de 150 mg/día y 8% con la dosis doblada; 34% no aliviaron. En el grupo de pacientes tratado con T el dolor alivió en 62% de los pacientes con la dosis inicial de 200mg/día y 11% con la dosis doblada, mientras que 27% no experimentó alivio. Las diferencias entre los dos grupos no fueron significativas en cuanto a su eficacia analgésica. El grupo que recibió Tramadol presentó en forma significativa, mayor incidencia de efectos colaterales de intensidad leve: náusea (p: 0.05, RR: 0.62; IC95%: 0.38-1.01), mareo (p: 0.04; RR: 0.58; IC95%: 0.33-1.01) y pérdida de apetito (p: 0.001; RR: 0.08; IC95%: 0.01-0.59). Conclusión. No existen diferencias en cuanto a la eficacia analgésica de CA y T en el tratamiento del dolor por cáncer. Con el uso de T se presentó una mayor incidencia de efectos colaterales de intensidad leve

Determinación de la eficacia analgésica de los bloqueos del ganglio estrellado en el síndrome doloroso regional complejo con dolor mediado por el sistema nervioso simpático: estudio preliminar / Study of the analgesic efficacy of stellate ganglion blockade in the management of the complex regional pain syndrome in patients with pain mediated by sympathetic nervous system: preliminary study

Objetivo: Este estudio fue realizado con el propósito de determinar la eficacia analgésica de los bloqueos del ganglio estrellado, en el alivio del dolor mediado por el sistema nervioso simpático, en pacientes con síndrome doloroso regional complejo. Pacientes y métodos: Se realizó un ensayo clínico controlado con asignación aleatoria y enmascaramiento simple. Treinta y nueve pacientes fueron tratados con una serie de bloqueos de ganglio estrellado, terapia física y tratamiento farmacológico, mientras que treinta y dos pacientes fueron tratados con fisioterapia y el mismo esquema farmacológico. Para determinar la asociación entre las variables se utilizó el riesgo relativo con sus respectivos intervalos de confianza. Resultados: En la evaluación clínica realizada un mes postratamiento se encontró alivio del dolor en 84,6% de los pacientes del grupo de intervención y en 78,1% de los controles (RR= 1,08; I.C. 95%=0,8-1,4; p=0.48), sin encontrarse diferencias estadísticamente significativas. No se encontró asociación entre la eficacia analgésica y tabaquismo, dominancia, género, tipo de SDRC, causa desencadenante y nivel educativo (AU)

Objective: The purpose of this study was to determine the analgesic efficacy of stellate ganglion blockade in pain mediated by the sympathetic nervous system in patients with Complex Regional Pain Syndrome (CRPS). Patients and methods: A randomized, simple-blinded controlled clinical trial was conducted. Thirty nine patients were randomly assigned to an intervention group which was treated with a series of stellate ganglion blockades, physical therapy and pharmacological treatment, and thirty two to a control group which was treated with physical therapy and the same pharmacological treatment. Risk ratio was used to evaluate outcome and determine association with predictor variables. Results: At the end of the first month post treatment, it was found that 84.6% of patients in the intervention group had alleviation of their pain while 78.1% of the control group had alleviation of their pain; there was not a statistically significant difference (RR=1.08; C.I. 95%=0.8-1.4; p=0.48). We found no association between analgesic efficacy, smoking, dominance, gender, and type of CRPS, unleashing cause or educational level (AU)

Moving embedded lattice solitons.

It was recently proved that solitons embedded in the spectrum of linear waves may exist in discrete systems, and explicit solutions for isolated unstable embedded lattice solitons (ELS) of a differential-difference version of a higher-order nonlinear Schrodinger equation were found [Gonzalez-Perez-Sandi, Fujioka, and Malomed, Physica D 197, 86 (2004)]. The discovery of these ELS gives rise to relevant questions such as the following: (1) Are there continuous families of ELS? (2) Can ELS be stable? (3) Is it possible for ELS to move along the lattice? (4) How do ELS interact? The present work addresses these questions by showing that a novel equation (a discrete version of a complex modified Korteweg-de Vries equation that includes next-nearest-neighbor couplings) has a two-parameter continuous family of exact ELS. These solitons can move with arbitrary velocities across the lattice, and the numerical simulations demonstrate that these ELS are completely stable. Moreover, the numerical tests show that these ELS are robust enough to withstand collisions, and the result of a collision is only a shift in the positions of the solitons. The model may apply to the description of a Bose-Einstein condensate with dipole-dipole interactions between the atoms, trapped in a deep optical-lattice potential.

Anisotropy and nonequilibrium effects on the light scattered from suspension in a nematic solvent.

We investigate the effects produced on the light scattering spectrum by the anisotropic diffusion of impurities in an incompressible nematic solvent. The spectrum is calculated by using a fluctuating hydrodynamic description when the system is both in a fully thermodynamic equilibrium state and in a nonequilibrium steady state induced by a dye-concentration gradient. In the former state, the isotropic pretransitional phase as well as the nematic phase of the solvent are considered. This spectrum is symmetric (Lorentzian) with respect to the frequency shifts, but anisotropic through its explicit dependence on the ratio of the diffusion coefficients of the dye parallel and normal to the mean molecular axis of the nematic. The values of these coefficients were taken from experimental measurements of diffusion of methylred and nitrosodimethylaniline in a N -( p -methoxybenzylidene)- p -butylaniline (MBBA) solvent. This anisotropy changes the height and the width at mid height with respect to the isotropic case in amounts which for MBBA vary up to 36% and 26%. We also calculate the spectrum in the presence of a concentration gradient of the dye and find that its presence gives rise to an asymmetry of the spectrum in its dependence on the frequency shift; its maximum increases and is displaced with respect to its equilibrium position. The size and direction of this shift are proportional to the magnitude of the dye-concentration gradient and depend on its relative orientation with respect to the scattering vector. For small dimensionless concentration gradients ( approximately 10(-2) ), this effect is maximum when these vectors are parallel and the scattering angle is low ( approximately 1 degrees ). The maximum degree of departure from equilibrium is significant and turns out to be approximately 55%. In view of the significant changes in the spectrum, our theoretical analysis suggests that these effects might be observable.

Absorption effects in liquid crystal waveguides.

An analytical and numerical study of the propagation of optical fields through a nematic hybrid slab is developed. We take into account explicitly the absorption of radiation by the liquid crystal by introducing a complex dielectric tensor. For a low intensity beam we first derive the eikonal equation and from it we calculate the ray trajectories in the optical limit. We show that in the presence of absorption, there are no caustics within the slab. Then we consider the WKB limit and calculate the field transverse magnetic modes, their number and their cutoff frequencies. We show that for both limits the agreement between our analytical and numerical results for the propagation constants is excellent, while there are larger differences in the analytically and numerically calculated field amplitudes. These differences show that absorption effects are important for this quantity and have their origin in the fact that the chosen parameter values in our exact numerical calculations, strictly speaking, do not lie within the limits of validity of the WKB approximation. Although a more precise comparison between these approaches requires the use of different sets of values of the relevant parameters, our analysis shows the effects and complications arising from the inclusion of absorption. Finally, we discuss the scope and limitations of our approach.

Standard and embedded solitons in nematic optical fibers.

A model for a non-Kerr cylindrical nematic fiber is presented. We use the multiple scales method to show the possibility of constructing different kinds of wave packets of transverse magnetic modes propagating through the fiber. This procedure allows us to generate different hierarchies of nonlinear partial differential equations which describe the propagation of optical pulses along the fiber. We go beyond the usual weakly nonlinear limit of a Kerr medium and derive a complex modified Korteweg-de Vries equation (CM KdV) which governs the dynamics for the amplitude of the wave packet. In this derivation the dispersion, self-focussing, and diffraction in the nematic fiber are taken into account. It is shown that this CM KdV equation has two-parameter families of bright and dark complex solitons. We show analytically that under certain conditions, the bright solitons are actually double-embedded solitons. We explain why these solitons do not radiate at all, even though their wave numbers are contained in the linear spectrum of the system. We study (numerically and analytically) the stability of these solitons. Our results show that these embedded solitons are stable solutions, which is an interesting property since in most systems the embedded solitons are weakly unstable solutions. Finally, we close the paper by making comments on the advantages as well as the limitations of our approach, and on further generalizations of the model and method presented.

[Electrophoresis of cerebrospinal fluid proteins in patients with ischemic cerebrovascular disease]. / Electroforesis de proteínas del líquido cefalorraquídeo en pacientes con enfermedad cerebrovascular isquémica.

INTRODUCTION: Cerebral infarction (CI) increases vascular permeability because of a torrent of molecular events that take place. It frequently leads to oedema, haemorrhage and neuronal death. Free radicals and proteases are also formed, which cause lesions in the blood vessels, and microvascular integrity is lost through degradation of the basal lamina and the extracellular matrix. As a result rupture of the blood brain barrier takes place. AIMS. To compare the electrophoretograms of patients with ischemic cerebrovascular disease (ICVD) with those of controls and to link the alterations in the proteinogram with the ICVD subtypes. PATIENTS AND METHODS: The CSF of 55 controls and 136 patients with ICVD was examined. The total protein (TP) concentration was determined and a polyacrylamide gel electrophoretogram was produced using Coomassie blue stain. Parallel to this, serum was prepared for haptoglobin staining. RESULTS: The TP in patients CSF rose to a significantly higher level than that of controls. Blood brain barrier damage (BBBD) was observed in 28.7% of the patients studied with CI and in 10.3% in transient ischemic attacks (TIA), while 16.2% presented oligoclonal bands. There was a difference between the two sexes: men were found to have higher TP levels, lower percentages of prealbumin 1 and more BBBD than women. CONCLUSIONS: BBBD is more frequent in infarctions than in TIA, and is predominant in men with thrombotic cerebral infarction.

Electroforesis de proteínas del líquido cefalorraquídeo en pacientes con enfermedad cerebrovascular isquémica / Electrophoresis of cerebrospinal fluid proteins in patients with ischemic cerebrovascular disease

Introducción. El infarto cerebral (IC) aumenta la permeabilidad vascular al ocurrir toda una cascada de eventos moleculares, y aparece con frecuencia edema, hemorragia y muerte neuronal. También ocurre la formación de radicales libres y proteasas que causan lesiones a los vasos sanguíneos, y se pierde la integridad microvascular por degradación de la lámina basal y la matriz extracelular; todo esto conduce a la ruptura de la barrera hematoencefálica. Objetivos. Comparar el electroforetograma de pacientes con enfermedad cerebrovascular isquémica (ECVI) con los controles y asociar las alteraciones del proteinograma con los subtipos de ECVI. Pacientes y métodos. Se estudió el LCR de 55 controles y 136 pacientes con ECVI. Se determinó la concentración de proteínas totales (PT) y el electroforetograma en geles de disco de poliacrilamida con tinción de Coomassie; el suero se procesó en paralelo para tinción de haptoglobinas. Resultados. Las PT en el LCR de los pacientes se elevaron significativamente más que en los controles. El daño de barrera hematoencefálica (DBHE) se observó en el 28,7 por ciento de los pacientes estudiados con IC y en el 10,3 por ciento en los ataques isquémicos transitorios, mientras que el 16,2 por ciento presentaron bandas oligoclonales. Hubo diferencia entre ambos sexos: los hombres tuvieron los niveles de PT elevados, menor porcentaje de prealbúmina-1 y más DBHE que las mujeres. Conclusión. El DBHE es más frecuente en los infartos que en los AIT, y predominan en los hombres con infarto cerebral trombótico (AU)