Acute food deprivation-induced relapse to heroin seeking after short and long punishment-imposed abstinence in male rats.

RATIONAL: Stress is a major trigger for drug relapse in humans and animal models, even after prolonged abstinence. However, animal models for stress-induced relapse were criticized for the lack of predictive and face validity. OBJECTIVES: Here we investigated the effect of acute food deprivation stress in a novel stress-induced relapse model using voluntary, punishment-imposed abstinence from heroin. We also performed a detailed characterization of the development of punishment-imposed abstinence. METHODS: Male rats were trained to self-administered heroin (0.1 mg/kg/infusion) for 2 weeks, using the seeking-taking chained schedule. Pressing the 'seeking' lever led to the insertion of the 'taking' lever and pressing the take lever resulted in heroin infusion. Following self-administration training, rats were exposed to 8 or 21 days of heroin-seeking punishment. During punishment, 30% of the completed seek links resulted in a mild escalating footshock instead of take lever presentation. Next, rats were tested for heroin seeking under extinction conditions after 24 h of food deprivation and sated conditions. RESULTS: Probabilistic punishment of seeking lever responses resulted in gradual suppression of heroin seeking and taking. Exposure to food-deprivation stress induced a robust relapse to heroin seeking after short and long punishment-imposed abstinence periods, without significant effects of time, i.e., no incubation of heroin seeking. Individual differences were observed in the development of punishment-induced abstinence and stress-induced relapse. CONCLUSIONS: These results suggest that stress is a reliable trigger to relapse even after a prolonged period of punishment-induced, voluntary abstinence.

Ca2+ signaling driving pacemaker activity in submucosal interstitial cells of Cajal in the murine colon.

Interstitial cells of Cajal (ICC) generate pacemaker activity responsible for phasic contractions in colonic segmentation and peristalsis. ICC along the submucosal border (ICC-SM) contribute to mixing and more complex patterns of colonic motility. We show the complex patterns of Ca2+ signaling in ICC-SM and the relationship between ICC-SM Ca2+ transients and activation of smooth muscle cells (SMCs) using optogenetic tools. ICC-SM displayed rhythmic firing of Ca2+transients ~ 15 cpm and paced adjacent SMCs. The majority of spontaneous activity occurred in regular Ca2+ transients clusters (CTCs) that propagated through the network. CTCs were organized and dependent upon Ca2+ entry through voltage-dependent Ca2+ conductances, L- and T-type Ca2+ channels. Removal of Ca2+ from the external solution abolished CTCs. Ca2+ release mechanisms reduced the duration and amplitude of Ca2+ transients but did not block CTCs. These data reveal how colonic pacemaker ICC-SM exhibit complex Ca2+-firing patterns and drive smooth muscle activity and overall colonic contractions.

Antibody affinity maturation using yeast display with detergent-solubilized membrane proteins as antigen sources.

Antigen preparations in the form of detergent-solubilized cell lysates could, in principle, render membrane proteins (MPs) compatible with in vitro antibody engineering technologies. To this end, detergent-solubilized cell lysates were coupled with the yeast surface display platform to affinity mature an anti-transferrin receptor (TfR) single-chain antibody (scFv). Lysates were generated from TfR-expressing HEK293 cells by solubilization with detergent-containing buffer after undergoing plasma membrane-restricted biotinylation. Lysate-resident TfR was then combined with a mutagenic anti-TfR scFv library in a competitive, dissociation rate screen, and scFvs were identified with up to 4-fold improved dissociation rates on the surface of yeast. Importantly, although the lysates contained a complex mixture of biotinylated proteins, the engineered scFvs retained their TfR binding specificity. When secreted by yeast as soluble proteins, mutant scFvs bound to cell surface TfR with 3-7-fold improvements in equilibrium binding affinity. Although a known MP antigen was targeted for purposes of this study, employing biotin tagging as a means of antigen detection makes the lysate-based approach particularly flexible. We have previously shown that yeast display can be used to identify lead antibodies using cell lysate-resident MP antigens, and combined with this work showing that antibodies can also be quantitatively engineered using cell lysates, these approaches may provide a high-throughput platform for generation and optimization of antibodies against MPs.

Seudartrosis del escafoides del carpo. Consideraciones terapéuticas / No disponible

No disponible

Calcineurin-responsive zinc finger transcription factor CRZ1 of Botrytis cinerea is required for growth, development, and full virulence on bean plants.

Recently, we showed that the alpha subunit BCG1 of a heterotrimeric G protein is an upstream activator of the Ca(2+)/calmodulin-dependent phosphatase calcineurin in the gray mold fungus Botrytis cinerea. To identify the transcription factor acting downstream of BCG1 and calcineurin, we cloned the gene encoding the B. cinerea homologue of CRZ1 ("CRaZy," calcineurin-responsive zinc finger transcription factor), the mediator of calcineurin function in yeast. BcCRZ1 is able to partially complement the corresponding Saccharomyces cerevisiae mutant, and the subcellular localization of the green fluorescent protein-BcCRZ1 fusion product in yeast cells depends on the calcium level and calcineurin activity. Bccrz1 deletion mutants are not able to grow on minimal media and grow slowly on media containing plant extracts. Hyphal morphology, conidiation, and sclerotium formation are impaired. The cell wall and membrane integrity, stress response (extreme pH, H(2)O(2), Ca(2+), Li(+)), and ability of the hyphae to penetrate the intact plant surface are affected in the mutants. However, BcCRZ1 is almost dispensable for the conidium-derived infection of bean plants. The addition of Mg(2+) restores the growth rate, conidiation, and penetration and improves the cell wall integrity but has no impact on sclerotium formation or hypersensitivity to Ca(2+) and H(2)O(2). The expression of a set of recently identified BCG1- and calcineurin-dependent genes is also affected in DeltaBccrz1 mutants, confirming that this transcription factor acts downstream of calcineurin in B. cinerea. Since the Bccrz1 mutants still respond to calcineurin inhibitors, we conclude that BcCRZ1 is not the only target of calcineurin.

Valor práctico de las pruebas de electrodiagnóstico en el pronóstico del síndrome del túnel carpiano intervenido en una unidad de CMA / No disponible

Objetivo: El propósito del presente estudio fue establecer si existían relaciones entre los valores electrofisiográficos y la presentación de complicaciones en la evolución postquirúrgica en los pacientes intervenidos por síndrome del túnel carpiano. Material y métodos: Se realizó una revisión retrospectiva de 50 pacientes consecutivos intervenidos en una unidad de CMA mediante cirugía abierta del STC desde enero a diciembre de 2005. Se estudió la relación estadística entre el tiempo de latencia y la velocidad de conducción y la aparición de complicaciones o no abolición del problema tras la cirugía del síndrome del túnel carpiano. Resultados: Se encontró una inferencia estadística entre el tiempo de latencia y las complicaciones (p < 0,01), al igual que la velocidad (p < 0,01). También apareció una correlación estadísticamente significativa entre la velocidad de conducción y el tiempo de latencia (p < 0,01) (AU)

Objective: The purpose of the present study was to settle down if relationships existed between the values of electrodiagnosis and the presentation of complications in the evolution after surgery in the patients intervened by syndrome of the carpal tunnel. Material and methods: It was carried out a retrospective revision of 50 serial patients intervened in a unit of CMA by means of surgery open of the STC from January to December of 2005. The statistical relationship was studied between the time of latency and the conduction speed and the appearance of complications or non abolition of the problem after the surgery of the syndrome of the carpal tunnel. Results: It was a statistical inference between the time of latency and the complications (p < 0.01), the same as the speed (p < 0.01). Also appeared a correlation statistically significant between the conduction speed and the time of latency (p < 0.01) (AU)

Estudio del polietileno en artroplastia total de rodilla / No disponible

No disponible

Evaluación de calidad de la cirugía artroscópica en rodilla en CMA / Quality evaluation of knee artroscopy in ambulatory surgery

OBJETIVO: Evaluar la calidad de las intervenciones de artroscopia en nuestra unidad de cirugía mayor ambulatoria (UCMA) de nuestra hospital. MATERIAL Y MÉODO: Estudio retrospectivo de 218 procesos intervenidos entre abril de 1995 y junio de 2004. La edad media es de 41,4 años [15-71], con 148 (66,9%) varones y 73 (33,1%) mujeres. El 77% eran meniscopatías, el 11% condropatías, el 3,6% gonartrosis, el 1,3% síndromes del cíclope plastia LCA, el 1,3% cuerpos libres intra-articulares, y el 3,2% restante lo podemas etiquetar como “otros procesos”. Estudiamos el índice de sustitución, las complicaciones intraoperatorias y postoperatorias inmediatas, el porcentaje de suspensiones operatorias, el número de ingresos diferidos o reingresos en planta de traumatología y realizamos una encuesta de satisfacción telefónica. RESULTADOS: Índice de sustitución del 21,62% en el 2003. Sólo 3 pacientes presentaron complicaciones intraoperatorias y el 24.3% complicaciones postoperatorias inmediatas (el 17,4% dificultades micciones). Se suspendieron 5 intervenciones intervenciones (2,26%). Hubo 1 ingreso diferido (0,45%) y 5 reingresos (2,26%). En la encuesta un 85% de los pacientes se encuentran satisfechos y un 76% volvería a una UCMA (AU)

To evaluate the quality of arthroscopic knee operations in our ambulatory surgical units. Material and methods: A retrospective study of 218 procedures performed between April 1995 and June 2004. Mean age was 41.4 years [15-71], with 148 (66.9%)males and 73 (33.1%) women. 77% of the procedures were meniscal tears, 11% cartilage degenerations, 3,5% knee ostoarthritis, 1.3% anterior cruciate ligamente injury (ACL,) 1.3% cyclops syndrome after ACL reconstruction, 1.3% intra-articular free bodies, and the 3.2% remainder was classified as “other procedures”. We studied the replacement index, the early postoperative and intraoperative complications, the percentage of operations suspended, the number of postponed admissions or readmissions to the orthopaedics department and we carried out a satisfaction survey by phone (AU)

Modelo de interfaz cemento-vástago en artroplastias totales de cadera. Estudio de la superficie con elementos finitos / Cement-femoral stem interface model in total hip prosthesis: study of the surface with finite element

Introducción. La separación entre el cemento y el implante femoral se relaciona con los aflojamientos asépticos y con la supervivencia de los implantes. El objetivo del trabajo es el desarrollo de un modelo de daño que simule la degradación del cemento y el aflojamiento del implante, con dos acabados superficiales del vástago. Material y método. Aplicamos un modelo axisimétrico de elementos finitos de un vástago rodeado por una capa de cemento. La carga de compresión aplicada al vástago varía de 0 a 7 kN con frecuencia de 1 Hz durante 1,7 millones de ciclos. Una vez que se soltó la interfaz se incorporó rozamiento entre ambas superficies. Resultados. En los vástagos lisos el daño estimado en el cemento estaba más distribuido, siendo el daño global menor. En los rugosos hay mayor concentración del daño y mayor degradación del cemento en la zona distal, continuándose por la zona proximal. Conclusión. La simulación con elementos finitos permite predecir el comportamiento de los implantes relacionando macrogeometría y superficie. En nuestro modelo se demuestra la influencia del acabado superficial del vástago en la localización e intensidad del daño en el cemento y en la interfaz (AU)

Introduction. Debonding of the stem-cement interface is one of the most important causes aseptic loosening of the femoral stem, and it is related with the implant survival. The main goal of this study is the development of a damage model, in order to simulate the cement degradation and the debonding process of the stem-cement interface, respectively. We would consider two different surfaced finishing of the stem. Materials and methods. An axisymetric finite element model of a stem and the surrounding cement mantle was developed. The cement damage model was also implemented to simulate its degradation. The stem was gradually compressed in the cement by a dynamic, sinusoidal axial force, cycling between 0 and 7 kN for 1.7 million cycles at a frequency of 1 Hz. When the interface is completely debonded, contact friction is incorporated between both surfaces. Results. Subsidence is higher in the polished stems because the stem-cement interface is completely debonded. Cement damage in the polished stem is more distributed and quantitatively is lower than for the rough stems, where cement damage is more concentrated distally. Conclusion. Finite element models are able to predict the behaviour of implants relating the stem geometry with its surface finished. The influence of the surface finished on the cement damage and debonding process of the stem-cement interface have been demonstrated with the model proposed (AU)

Osteosíntesis de fracturas del fémur distal con placas LISS / Distal femoral fractures; treatment with less invasive stabilitation system (L. I. S. S.)

Las fracturas del fémur distal son complejas en su tratamiento y asocian múltiples complicaciones evolutivas com pseudoartrosis, callos viciosos, gonartrosis o infección secundaria a cirugía abierta agresiva, por lo que han surgido las osteosíntesis mínimamente invasivas dentro de las cuales se sitúa la placa LISS. Analizamos los resultados tras 10 meses de seguimiento de 14 pacientes con fractura del fémur distal tratados con placa LISS. Los tiempos de consolidación no fueron muy divergentes respecto a series mayores, la incidencia de retrasos de consolidación y callos viciosos, baja. No hubo pseudoartrosis, fracasos del material, aflojamientos, infecciones, tromboembolismos ni algodistrofias. Por ello, consideramos que los resultados obtenidos con este implante son satisfactorios

The treatment of the distal femoral fractures is difficult in order to the surgery and múltiple complications, like pseudoartrosis,c allus vicious, gonartrosis or infection because open surgery. So that it has arised the minimun invasive system of osteosynthesis like LISS plate. We have assessed outcomes in 14 patients with distal femoral fractures treated with that implant. The mean follow up was 10 months. The times of consolidation was similar than other bigger series of patients and low incidence of delayed consolidation and callus vicious. There has not been any case of pseudoartrosis, failure of implant, loosenin, infections, tromboembolism or algodystrophia, so that considered that we has obtained good results

Functional characterization of the Candida albicans CRZ1 gene encoding a calcineurin-regulated transcription factor.

Calcineurin is a phosphoprotein phosphatase devoted to the transduction of Ca(2+)-signals in eukaryotes. In the human pathogen Candida albicans, calcineurin function is required for cell morphogenesis, azole tolerance, membrane stress responses, survival in serum and virulence in mice. Molecular mechanisms as well as targets downstream C. albicans calcineurin involved in all these processes are still uncharacterized. Here we report the characterization of a C. albicans Crz1 calcineurin-regulated transcription factor using a Saccharomyces cerevisiae crz1Delta defective strain as heterologous host. CaCrz1p fulfils the function of its S. cerevisiae homolog protein to control the expression of several Ca(2+)/calcineurin-responsive genes acting on the CDRE sequence in promoters. In the model yeast, CaCrz1p activity and localization are regulated by calcineurin. Deletion of CRZ1 gene renders C. albicans hypersensitive to alkaline cations and membrane stress conditions, including that elicited by SDS and antifungal azoles. Our findings indicate that CaCrz1p is member of a calcium-regulated pathway required for the maintenance of membrane integrity.

Simulación en 3D con elementos finitos de un modelo de prótesis de rodilla / Three-dimensional finite-elements simulation of a model of knee prosthesis

El análisis mediante elementos finitos (AEF) viene aplicándose en la bibliografía al estudio biomecánico de las prótesis de rodilla. Material y método. En nuestro trabajo hemos realizado un modelo de articulación de rodilla y otro de artroplastia de rodilla mediante AEF, estudiando el efecto de las cargas sobre ambos modelos en la fase de soporte unilateral a 0º y 15º de flexión. Se han comparado los desplazamientos, las tensiones en dirección vertical para el tejido óseo y las tensiones de Von Mises para los implantes protésicos. Resultados. En extensión los desplazamientos obtenidos con la rodilla anatómica son mayores que con artroplastia. En la rodilla con artroplastia se produce una mayor concentración de tensiones a nivel de la cabeza femoral, mientras que en el modelo de rodilla anatómica la distribución es más uniforme. El componente tibial es el que más trabaja, sobre todo en la zona del vástago pero también en la bandeja metálica. Conclusiones. A pesar de las limitaciones del modelo, podemos afirmar que el AEF permite realizar un estudio biomecánico del comportamiento estructural de la articulación de la rodilla y la rodilla con artroplastia. (AU)

Nonunion of the patella as a late chance observation after reconstructive surgery of the anterior cruciate ligament.

The use of autologous bone-tendon-bone grafts for reconstructive surgery of the anterior cruciate tendon is a widely diffused technique. Fracture of the donor patella constitutes an uncommon complication. It is the purpose of this study to present the clinical case of a patient submitted to reconstructive surgery of the anterior cruciate ligament where the existence of asymptomatic nonunion of the patella was by chance observed.

Restoration of facial contour in Romberg's disease and hemifacial microsomia: experience with 118 cases.

The experience with free flaps and conventional reconstructive procedures for 118 patients with Rombergapos;s disease and hemifacial microsomia over a 10-year period is presented. The groin free flap was used most frequently for patients with Rombergapos;s disease, whereas the scapular free flap was used for patients with hemifacial microsomia. The rectus abdominis or the latissimus dorsi free flap was chosen only when additional volume was required. To achieve better contour, secondary procedures, such as defatting the flap, pedicled temporal fascial flaps, cartilage and bone grafts, orthognathic surgery, and bone distraction were performed in severe cases. For patients with Rombergapos;s disease, excellent results were achieved in 35% (n = 28) of mild cases, in 72% (n = 27) out of 38 moderately and in 41% (n = 5) out of 12 severely affected patients. In hemifacial microsomia group (n = 40) excellent results were obtained in 66% of cases.

Free flaps for head and neck reconstruction in non-oncological patients: experience of 200 cases.

Two hundred free flaps for reconstructing the head and neck regions in 192 patients with non-oncological pathology were studied. Pathological entities included Romberg's disease, hemifacial microsomia, acquired facial palsy, trauma, and burn sequelae. Indications for selecting a specific free flap for reconstructing each case, details of anastomoses, reexploration, flap success, operative time, length of hospitalization, and complications were studied. The long-term results of cosmetic and function were also obtained. Patient age ranged from 6 to 40 years. The most common diagnosis was Romberg's disease 39% (n = 75), followed by hemifacial microsomia 20% (n = 40). The free flap most frequently used was the scapular 32% (n = 64), followed by the groin free flap 21% (n = 42). A total of 190 flaps (95%) were successful, whereas only 10 (5%) were lost. The mean operative time was 5:30 h and the average hospital stay was only 6 days. There were no major complications and no deaths in the study group. The patients were followed for at least 1 year in all cases. It is concluded that free flaps are safe and reliable procedures for reconstructing complex head and neck non-oncological defects.

Carcinomatosis meníngea con celularidad y bioquímica normales en líquido cefalorraquídeo

No disponible

[Persistence of hypercoagulability state after hip and knee arthroplasty: what is the optimal duration of antithrombotic guidelines in this surgery?]. / Persistencia del estado de hipercoagulabilidad tras artroplastia de cadera y rodilla: cuál debe ser la duración óptima de las pautas antitrombóticas en esta cirugía?

Among 79 patients candidates to hip (53) and knee (26) replacement an evaluation was made of the influence of a two-week program with LMWH on the evolution of hypercoagulability markers: D-D, TAT, and F1 + 2. Measurements were performed by ELISA preoperatively and on days 1, 7 and about 45 postoperatively; in the latter, two extraction intervals were considered: < or = 45 days and > 45 days. With both surgical modalities, D-D and F1 + 2 peaked at 7th day postoperatively, whereas TAT peaked on day 1. Among D-D and F1 + 2 values quantitated on day 7th and the extraction interval < or = 45 days, no significant differences were obtained (Z < 2.64). The hypercoagulative chronicity exhibited by D-D and F1 + 2 during the first month and a half after this surgery, might require in some cases a more prolonged thromboprophylaxis.

Frontotemporal fasciocutaneous island flap for facial aesthetic subunit reconstruction.

The frontotemporal fasciocutaneous island flap is a useful source of tissue for correcting aesthetic units of the face. The quality of the tissue may be enhanced, and a successful color and texture match may be achieved. This flap is based on the temporal vessel system and its own fascia. Its provides excellent venous drainage and its pedicle length and arc of rotation may be increased. The donor scar is hidden under the hair-bearing area. The frontotemporal fasciocutaneous island flap was used in patients with inferior eyelid defects, for cheek reconstruction, for providing coverage of superior and inferior lip defects, for restoring the normal anatomy of columellar defects, and for reestablishing the contour of menton defects. The frontotemporal fasciocutaneous island flap was employed successfully in 9 patients at the Hospital Gea Gonzalez. The wide treatment possibilities for the reconstruction of aesthetic units in the face with the frontotemporal fasciocutaneous island flap are illustrated.