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La endometriosis es la presencia de tejido endometrial fuera del útero. La endometriosis intestinal y del tracto urinario son formas de endometriosis extragenital que se manifiestan con síntomas inespecíficos, pero su detección conlleva estrategias terapéuticas específicas. Las características de la enfermedad se han descrito con ecografía transvaginal y resonancia magnética en numerosas publicaciones, pero existen escasas referencias de ecografía abdominal.

Apenas conocemos cómo es la asistencia de los recién nacidos (RN) con encefalopatía hipóxico-isquémica (EHI) en hipotermia terapéutica (HT), especialmente si existen protocolos asistenciales, la neuromonitorización que se realiza o cómo es la aproximación al pronóstico neurológico. Este conocimiento permite detectar e implementar áreas de mejora asistencial.

Describir los hallazgos y el comportamiento de la ecografía con contraste en el estudio de los tumores uroteliales de vías superiores y evaluar su utilidad en el diagnóstico.

Los tumores de la vía biliar son lesiones benignas o malignas que pueden asociarse a factores de riesgo o a lesiones con potencial de malignización. Constituyen un grupo heterogéneo de entidades con diferente comportamiento biológico y pronóstico dependiendo de su localización y del tipo de crecimiento. En este artículo revisamos el papel del radiólogo para detectar, caracterizar y estadificar estos tumores y, sobre todo, la importancia de clasificarlos para planificar el manejo y el tratamiento.

La adolescencia es una etapa de la vida durante la cual se desarrolla la identidad sexual. En este período muchas ado- lescentes inician su actividad sexual. Por ello, es de vital im- portancia entregarles consejería, que debe considerar pre- vención de embarazo e infecciones de transmisión sexual, prevención de conductas de riesgo y favorecer la adquisición de conductas protectoras. El objetivo del presente artículo es entregar una propuesta de consejería integral enfocada en adolescentes. Está dirigido a los profesionales de la salud que tienen el enorme desafío y la responsabilidad de prevenir el embarazo no planificado y las infecciones de transmisión sexual; y apoyar a los adolescentes en el desarrollo de una sexualidad sana.

The concentrations of three toxic heavy metals, mercury (Hg), lead (Pb), and cadmium (Cd), were determined in preserved variegated scallops (Chlamys varia, Bivalvia, Mollusca), which are often consumed in Tenerife (Canary Islands, Spain). A total of 300 samples of seven commercial brands (A, B, D, H, J, L, and M) and one processed product (“scallop sauce”) were analyzed. Samples were collected weekly in a major shopping area in Santa Cruz de Tenerife during a 12-month period. The concentrations of lead and mercury were far below the maximum limit permitted for human consumption by the European Communities Commission regulation (EC) 466/2001 (1 and 0.5 mg kg−1wet weight for Pb and Hg, respectively). Concentrations of cadmium were close to the maximum limit permitted by regulation (EC) 466/2001 (1 mg kg−1wet weight).

We report a 4-year-old boy with two areas of woolly hair in the right parietotemporal region and a linear epidermal nevus in the areas of woolly hair as well as in the ipsilateral hemiface and chin. Evaluation by scanning electron microscopy showed woolly hair with oval transverse section and longitudinal groove. A complete examination ruled out associated anomalies.

Teledermatology is been currently introduced as a diagnostic tool in the daily practice of the dermatologist. Many published works regarding teleconsult show the high sensitivity and economic saving of this technique as a diagnostic method.

Summary: Coconut is one of the most recalcitrant species to regenerate in vitro. Although previous research efforts using plumule explants have resulted in reproducible somatic embryogenesis, efficiency is only 4 or 10 somatic embryos per plumule without or with a brassinolide treatment, respectively. In order to increase the efficiency of somatic embryogenesis in coconut, two different approaches were evaluated and reported here: secondary somatic embryogenesis and multiplication of embryogenic callus. Primary somatic embryos obtained from plumule explants were used as explants and formed both embryogenic callus and secondary somatic embryos. The embrogenic calluses obtained after three multiplication cycles were capable of producing somatic embryos. The efficiency of the system was evaluated in a stepwise process beginning with an initial step for inducing primary somatic embryogenesis followed by three steps for inducing secondary somatic embryogenesis followed by three steps for embryogenenis callus multiplication, and finally production of somatic embryos from callus. The total calculated yield from one plumule was 98 000 somatic embryos. Comparing this to the yield obtained from primary somatic embryogenesis results in about a 50 000-fold increase. When compared to the yield previously reported in the literature with the use of a brassinolide treatment, it is about a 10 000-fold increase in yield. The present protocol represents important progress in improvement in the efficiency of coconut somatic embryo production.

By using a semi-classical two-dimensional Monte Carlo simulation, simple devices (T-branch junctions (TBJs) and rectifying diodes) based on AlInAs/InGaAs ballistic channels are analysed. Initially, the model is validated by means of Hall-effect measurements of mobility and electron concentration in long (diffusive) channels. Then, quasi-ballistic transport at room temperature is confirmed in a 100 nm channel. Our simulations qualitatively reproduce the experimental results of electric potential measured in a TBJ appearing as a result of electron ballistic transport, and in close relation with the presence of space charge inside the structure. As examples of devices exploiting the ballistic transport of electrons, preliminary simulations of a multiplexor/demultiplexor and a rectifying diode are presented, demonstrating their capability for terahertz operation.

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In this paper, an ensemble 2D bipolar Monte Carlo simulator is employed for the study of static characteristics, high-frequency response and noise behaviour in a 0.3 µm gate-length n-MOSFET in common source configuration. Short-channel effects, such as velocity overshoot in the pinch-off region, together with the appearance of hot electrons at the drain end of the channel are observed in the static characteristics. Admittance parameters and the small-signal equivalent circuit have been calculated in order to characterize the dynamic response of the device. The use of a bipolar simulator allows one to study the dynamics of both types of carriers simultaneously. While the static results are dominated by the electron transport, the contribution of holes mainly affects the drain-substrate capacitive coupling. The noise behaviour of the simulated MOSFET is also studied (up to 40 GHz) by means of different parameters, such as the spectral densities of the current fluctuations at the drain and gate terminals (and their cross-correlation), normalized α, β and C parameters and NF_min . In the saturation regime, due to the presence of hot carriers, an increase in drain and gate noise with respect to the long-channel prediction has been found. Moreover, a stronger correlation between drain and gate noise is observed, especially at low drain current. Induced gate noise is found to play a crucial role in the determination of NF_min at high drain currents.

Bupivacaine‐induced cardiotoxicity increases in hypoxic and acidotic conditions. We have analysed the effects of R(+)bupivacaine on hKv1.5 channels stably expressed in Ltk−cells using the whole‐cell patch‐clamp technique, at three different extracellular pH (pHo), 6.5, 7.4 and 10.0.Acidification of the pHofrom 7.4 to 6.5 decreased 4 fold the potency of R(+)bupivacaine to block hKv1.5 channels. At pHo10.0, the potency of the drug increased ∼2.5 fold.Block induced by R(+)bupivacaine at pHo6.5, 7.4 and 10.0, was voltage‐ and time‐dependent in a manner consistent with an open state block of hKv1.5 channels.At pHo6.5, but not at pHo7.4 or 10.0, R(+)bupivacaine increased by 95±3 % (n=6; P<0.05) the hKv1.5 current recorded at −10 mV, likely due to a drug‐induced shift of the midpoint of activation (ΔV=−8.5±1.4 mV; n=7).R(+)bupivacaine development of block exhibited an ‘instantaneous’ component of block at the beginning of the depolarizing pulse, which averaged 12.5±1.8% (n=5) and 4.6±1.6% (n=6), at pHo6.5 and 7.4, respectively, and that was not observed at pHo10.0.It is concluded that: (a) alkalinization of the pHoincreases the potency of block of R(+)bupivacaine, and (b) at pHo6.5, R(+)bupivacaine induces an ‘agonist effect’ of hKv1.5 current when recorded at negative membrane potentials.

The N‐substituent of IQB‐9302 has the same number of carbons as bupivacaine, but it exhibits a different spatial localization (n‐butyl vscyclopropylmethyl). Thus, the study of the effects of IQB‐9302 enantiomers on hKv1.5 channels will lead to a better knowledge of the determinants of stereoselective block.The effects of the IQB‐9302 enantiomers were studied on hKv1.5 channels stably expressed in Ltk−cells using the whole‐cell configuration of the patch‐clamp technique. Drug molecular modelling was performed using Hyperchem software.Block induced by IQB‐9302 was stereoselective with the R(+) enantiomer being 3.2‐fold more potent than the S(−) one (KDof 17.8±0.5 μMvs58.6±4.0 μM).S(−)‐ and R(+)IQB‐9302 induced‐block was time‐ and voltage‐dependent consistent with an electrical distance from the cytoplasmic side of 0.173±0.022 (n=12) and 0.181±0.018 (n=10), respectively.Potency of block of pipecoloxylidide local anaesthetics was linearly related to the length between the cationic tertiary amine and the end of the substituent.Molecular modelling shows that only when S(−) and R(+) enantiomers are superimposed by their aromatic ring, their N‐substituents are in opposite directions, which can explain the stereospecific block induced by bupivacaine and IQB‐9302 with hKv1.5 channels.These results suggest that: (a) IQB‐9302 enantiomers block the open state of hKv1.5 channels, and (b) the length of the N‐substituent in these local anaesthetics and not its volume determines the potency and degree of their stereoselective hKv1.5 channel block.

Block of hKv1.5 channels by R‐bupivacaine has been attributed to the interaction of the charged form of the drug with an intracellular receptor. However, bupivacaine is present as a mixture of neutral and charged forms both extra‐ and intracellularly.We have studied the effects produced by the R(+) enantiomer of a quaternary bupivacaine derivative, N‐methyl‐bupivacaine, (RB+1C) on hKv1.5 channels stably expressed in Ltk−cells using the whole‐cell configuration of the patch‐clamp technique.When applied from the intracellular side of the membrane, RB+1C induced a time‐ and voltage‐dependent block similar to that induced by R‐bupivacaine. External application of 50 μMRB+1C reduced the current at +60 mV by 24±2% (n=10), but this block displayed neither time‐ nor voltage‐dependence.External RB+1C partially relieved block induced by R‐bupivacaine (61±2% vs56±3%, n=4, P<0.05), but it did not relieve block induced by internal RB+1C. In addition, it did not induce use‐dependent block, but when applied in combination with internal RB+1C a use‐dependent block that increased with pulse duration was observed.These results indicate that RB+1C induces different effects on hKv1.5 channels when applied from the intra or the extracellular side of the membrane, suggesting that the actions of bupivacaine are the resulting of those induced on the external and the internal side of hKv1.5 channels.

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A generalization of the classical Monte Carlo (MC) device simulation technique is proposed to simultaneously deal with quantum-mechanical phase-coherence effects and scattering interactions in tunneling devices. The proposed method restricts the quantum treatment of transport to the regions of the device where the potential profile significantly changes in distances of the order of the de Broglie wavelength of the carriers (the quantum window). Bohm trajectories associated to time-dependent Gaussian wavepackets are used to simulate the electron transport in the quantum window. Outside this window, the classical ensemble simulation technique is used. Classical and quantum trajectories are smoothly matched at the boundaries of the quantum window according to a criterium of total energy conservation. A simple one-dimensional simulator for resonant tunneling diodes is presented to demonstrate the feasibility of our proposal.

Clinical evaluation of nutritional status (NS) was performed in 75 rheumatoid arthritis patients. They were distributed according to functional class, radiological stage and other prognostic factors (rheumatoid factor, extraarticular disease, disease duration). Evaluation of the different anthropometrical measurements in this group of long-standing RA patients (average disease duration: 10 years) revealed a significant impairment of lean body mass (LBM), especially among those with greater disability (Functional Class III and IV). Patients in more severe radiological stages (Radiological Stage III and IV) or patients with extraarticular disease also presented a significant loss of LBM compared with a matched cohort of the general population and patients with a more benign-course disease. There was less impairment of the fat mass, according to our clinical evaluation. Serological parameters of undernutrition (albumin and transferrin) did not show significant differences among the groups of patients. Clinical evaluation of NS in RA patients is a useful procedure for recognising patients at high risk of related complications by means of their poor nutritional status.

We review recent results concerning the microscopic analysis of electronic noise in semiconductor unipolar structures in the frequency range where 1/f noise can be neglected. Calculations are based on a Monte Carlo simulator of the carrier motion self-consistently coupled with a Poisson solver. Both current- and voltage-noise operation modes are considered and their respective advantages illustrated. The analysis is applied to structures with increasing degree of complexity, that is: homogeneous materials, resistors, n+nn+diodes., Schottky-barrier diodes and GaAs MESFETs. The main sources of noise like diffusion, generation-recombination, coupling between velocity and local electric field fluctuations, etc. are treated in the presence of electric fields of arbitrary strength. Results should constitute the basis for a physical interpretation of electronic noise in most semiconductor materials and devices thus providing inputs for improving quality and reliability figures of merit.

The increasing number of multidrug-resistant Mycobacterium tuberculosis strains has stimulated the interest of investigators in finding a rapid method for susceptibility testing. We used commercially available rRNA DNA-bioluminescence-labelled probes (Accu-Probe, Gen Probe, Inc. San Diego, Calif.) for this purpose. The study was performed in three chronological steps. (i) We studied the correlation between the photometric light units (PLUs) given by the hybridization method, the numbers of CFU per milliliter, and turbidity as nephelometric units for six different inocula of an M. tuberculosis strain over 14 days. A good correlation (c > 0.9; P < 0.05) was found from the third day for all concentrations used. (ii) Over a period of 14 days we studied the evolution of the PLUs for 20 strains growing in medium with 0.2 microl of isoniazid (H) per ml and 18 strains in medium with 1 microl of rifampin (R) per ml to standardize the method. Susceptible and resistant strains were used according to the reference proportions method in Middlebrook 7H10, and the MICs were determined in solid and liquid media. The final inoculum of a 10(-2) dilution from a McFarland no. 1 standard and reading at 3 and 5 days provided the best results. A quotient was established to find a cutoff point between resistant and susceptible strains. (iii) We used the standardized parameters in 117 tests with H and R. On day 3, the sensitivity, specificity, positive predictive value, and negative predictive value for detecting resistant strains were 86.8, 100, 100, and 90.1%, respectively, and on day 5 they were 96.2, 100, 100, and 94%, respectively. We concluded that the method is readily available, is easy to perform, and could be useful for screening resistant M. tuberculosis strains.

El abdomen agudo es un motivo de consulta habitual en los servicios de urgencias. Sus causas son múltiples, y entre ellas se encuentran diversas enfermedades del tracto gastrointestinal. Si bien la tomografía computarizada es la técnica más aceptada, con frecuencia se lleva a cabo una ecografía abdominal inicialmente, mediante la cual es posible establecer la sospecha de patología intestinal. Este artículo describe las características ecográficas de diversos trastornos intestinales que cursan con abdomen agudo, como la diverticulitis aguda, la obstrucción intestinal, la perforación gastrointestinal, la isquemia intestinal, la necrosis aguda de la grasa intraabdominal y una miscelánea de procesos, como endometriosis, cuerpos extraños o vasculitis. Debemos conocer las diferentes apariencias ecográficas del intestino anormal, ya que pueden detectarse incidentalmente en pacientes en quienes no se sospecha clínicamente. La semiología ecográfica de la patología intestinal, así como la apendicitis aguda, la enfermedad inflamatoria intestinal o las enfermedades infecciosas, se tratan en otros artículos de la serie.

We present a microscopic analysis of shot-noise suppression due to long-range Coulomb interaction in semiconductor samples operating between ballistic and diffusive transport regimes. We find that the strong suppression observed under the ballistic regime persists under quasi-ballistic conditions, before being washed out when a complete diffusive regime is achieved.

We present a generalized transfer field method with the microscopic noise sources directly connected with the velocity and energy change during single scattering events. The advantages of this method are illustrated by hydrodynamic calculations of current and voltage noise spectra in several two-terminal submicron structures.

We review recent theoretical investigations of shot-noise suppression in nondegenerate semiconductor structures surrounded by two contacts acting as thermal reservoirs. Calculations make use of an ensemble Monte Carlo simulator self-consistently coupled with a one-dimensional Poisson solver. By taking the doping of the injecting contacts and the applied voltage as variable parameters, the influence of elastic and inelastic scattering as well as of tunneling between heterostructures in the active region is investigated. In the case of a homogeneous structure at T = 300 K the transition from ballistic to diffusive transport regimes under different contact injecting statistics is analysed and discussed. Provided significant space-charge effects take place inside the active region, long-range Coulomb interaction is found to play an essential role in suppressing shot noise at applied voltages much higher than the thermal value. In the elastic diffusive regime, momentum space dimensionality is found to modify the suppression factor γ, which within numerical uncertainty takes values respectively of about ⅓, ½ and 0·7 in the 3D, 2D and 1D cases. In the inelastic diffusive regime, shot noise is suppressed to the thermal value. In the case of single and multiple barrier non-resonant heterostructures made by GaAs/AlGaAs at 77 K, the mechanism of suppression is identified in the carrier inhibition to come back to the emitter contact after having been reflected from a barrier. This condition is realised in the presence of strong inelastic scattering associated with emission of optical phonons. At increasing applied voltages for a two-barrier structure, shot noise is suppressed up to about a factor of 0·50 in close analogy with the corresponding resonant barrier-diode. For an increasing number of barriers, shot noise is found to be systematically suppressed to a more significant level by following approximately a 1/(N + 1) behaviour, N being the number of barriers. This mechanism of suppression is expected to conveniently improve the signal-to-noise ratio of these devices.

Cephalopods are the sole invertebrates included in the list of regulated species following the Directive 2010/63/EU. According to the Directive, achieving competence through adequate training is a requisite for people having a role in the different functions (article 23) as such carrying out procedures on animals, designing procedures and projects, taking care of animals, killing animals. Cephalopod Biology and Care Training Program is specifically designed to comply with the requirements of the "working document on the development of a common education and training framework to fulfil the requirements under the Directive 2010/63/EU". The training event occurred at the ICM-CSIC in Barcelona (Spain) where people coming from Europe, America and Asia were instructed on how to cope with regulations for the use of cephalopod molluscs for scientific purposes. The training encompasses discussion on the guidelines for the use and care of animals and their welfare with particular reference to procedures that may be of interest for neuroscience. Intensive discussion has been carried out during the training sessions with focus on behavioural studies and paradigms, welfare assessment, levels of severity of scientific procedures, animal care, handling, transport, individual identification and marking, substance administration, anaesthesia, analgesia and humane killing.