Posible superfetación en una coneja raza NZB (Oryctolagus cuniculus) concomitante a retraso del desarrollo intrauterino (RDIU)

Reproductive disorders among rabbits are complex and numerous, including such rare disorders as Superfetation (sf). A possible case of sf that was accidentally discovered is described, associated with dystocia in a female nzb breed rabbit, suffering from severe vaginal hemorrhaging, prostration, hypothermia and lack of reaction to stimuli. During palpation, numerous fetuses were detected in both uterine horns that did not respond to obstetric manipulation for extraction. An emergency cesarean section revealed six fetuses; the largest was dead in a caudal position, blocking the birth canal near the cervix, while another less-developed fetus was outside of the right uterine horn within a litter of seven young rabbits. The mother was euthanized in extremis using sodium pentothal. Morphologically, the developed fetuses weighed 65.8, 70.7, 61.3, 68.4, 53.7 and 65.3 grams, respectively; the underdeveloped fetus weighed 19.5 grams and had abundant meconium, which was not found among the others. The total body lengths analogically determined under the cephalocaudal criterion (cc) were 10.7, 11.2, 9.9, 10.9, 8.6 and 9.2 cm, respectively, and just 3.9 cm for the underdeveloped fetus, with no evidence of malformations or infection. Based on clinical-surgical observations, the primary diagnosis was obstructive dystocia, associated with fetal underdevelopment and secondary uterine inertia. Morphological comparison of the underdeveloped fetus was postulated as superfetation along with gestation/dystocia, with no information on fetal death or maceration. The records indicate that while already pregnant, the mother was re-mated. However, it is unclear how the female experienced a second implantation and a notable delay in the maturation of a single fetus.Los trastornos reproductivos del conejo son complejos y numerosos incluyendo rarezas como la superfetación (SF). Se describe un posible caso de SF descubierto accidentalmente, asociado a distocia en una coneja de la raza nzb, que sufre de severa hemorragia vaginal, postración, hipotermia y no reactiva al estímulo. Durante la palpación, numerosos fetos fueron detectados en ambos cuernos uterinos sin respuesta a la manipulación obstétrica para extracción. La cesárea urgente reveló seis productos a término; uno de talla superior muerto en posición caudal bloqueando el canal de parto cerca del cuello uterino, y uno más subdesarrollado retirado del cuerno uterino derecho entre una camada de siete gazapos. La madre se eutanizó in extremis mediante sobredosis de Pentotal Sódico. Morfológicamente, los fetos a término registraron pesos de 65,8, 70,7, 61,3, 68,4, 53,7 y 65,3 gramos, respectivamente; el crío subdesarrollado pesó 19,5 gramos y presentó meconio abundante ausente en el resto. Las longitudes corporales totales (lCT) realizadas análogamente bajo criterio céfalo-caudal (CC), reportaron 10,7, 11,2, 9,9, 10,9, 8,6 y 9,2 cm, respectivamente, y sólo 3,9 cm para el crío subdesarrollado, sin evidencia de malformaciones o infección. Basado en observaciones clínico-quirúrgicas el diagnóstico primario fue de distocia obstructiva, asociada a un sobredesarrollo fetal e inercia uterina secundaria. La comparación morfológica del crío subdesarrollado se postuló como superfetación concomitante a gestación/distocia, sin datos de muerte fetal o maceración. Los registros apuntan que estando gestante esta hembra fue re-apareada. Sin embargo, no está claro cómo la coneja experimentó una segunda implantación y notable retraso en la maduración de un solo feto

XIORT-MC: A real-time MC-based dose computation tool for low- energy X-rays intraoperative radiation therapy

El texto completo de este trabajo no se encuentra disponible por no haber sido facilitado aún por su autor, por restricciones de copyright, o por no existir una versión digitalPurpose The INTRABEAM system is a miniature accelerator for low-energy X-ray Intra-Operative Radiation Therapy (IORT), and it could benefit from a fast and accurate dose computation tool. With regards to accuracy, dose computed with Monte Carlo (MC) simulations are the gold standard, however, they require a large computational effort and consequently they are not suitable for real-time dose planning. This work presents a comparison of the implementation on Graphics Processing Unit (GPU) of two different dose calculation algorithms based on MC phase-space (PHSP) information to compute dose distributions for the INTRABEAM device within seconds and with the accuracy of realistic MC simulations. Methods The MC-based algorithms we present incorporate photoelectric, Compton and Rayleigh effects for the interaction of low-energy X-rays. XIORT-MC (X-ray Intra-Operative Radiation Therapy Monte Carlo) includes two dose calculation algorithms; a Woodcock-based MC algorithm (WC-MC) and a Hybrid MC algorithm (HMC), and it is implemented in CPU and in GPU. Detailed MC simulations have been generated to validate our tool in homogeneous and heterogeneous conditions with all INTRABEAM applicators, including three clinically realistic CT-based simulations. A performance study has been done to determine the acceleration reached with the code, in both CPU and GPU implementations. Results Dose distributions were obtained with the HMC and the WC-MC and compared to standard reference MC simulations with more than 95% voxels fulfilling a 7%-0.5 mm gamma evaluation in all the cases considered. The CPU-HMC is 100 times more efficient than the reference MC, and the CPU-WC-MC is about 50 times more efficient. With the GPU implementation, the particle tracking of the WC-MC is faster than the HMC, with the extraction of the particle's information from the PHSP file taking a major part of the time. However, thanks to the variance reduction techniques implemented in the HMC, up to 400 times less particles are needed in the HMC to reach the same level of noise than the WC-MC. Therefore, in our implementation for INTRABEAM energies, the HMC is about 1.3 times more efficient than the WC-MC in an NVIDIA GeForce GTX 1080 Ti card and about 5.5 times more efficient in an NVIDIA GeForce RTX 3090. Dose with noise below 5% has been obtained in realistic situations in less than 5 s with the WC-MC and in less than 0.5 s with the HMC. Conclusions The XIORT-MC is a dose computation tool designed to take full advantage of modern GPUs, making possible to obtain MC-grade accurate dose distributions within seconds. Its high speed allows a real-time dose calculation that includes the realistic effects of the beam in voxelized geometries of patients. It can be used as a dose-planning tool in the operating room during a XIORT treatment with any INTRABEAM device.Gobierno de EspañaComunidad de MadridUnión EuropeaUniversidad Complutense de MadridDepto. de Estructura de la Materia, Física Térmica y ElectrónicaFac. de Ciencias FísicasInstituto de Física de Partículas y del Cosmos (IPARCOS)TRUEpu