Artroplastia total no cementada en la coxartrosis secundaria a displasia y luxación congenita de cadera

Se revisan 13 prótesis no cementadas implantadas en 12 paciente s que presentaban una coxartrosis secundaria a una displasia congénita de cadera. Los paciente s han sido seguidos más de 2 años de evolución. En todos los casos se utilizó la via de abordaje postero-lateral. Se implantó siempre la prótesis tipo PCA procediéndose en 7 casos a la realización, a nivel acetabular, de un alo o autoinjerto complementario. A nivel femoral se utilizaron 7 vástagos estándar, 3 medianos y 3 largos para facilitar la restauración del centro rotatorio original de la cadera. En los pacientes que presentaban una luxación importante se llevaron a cabo osteotomías de acortamiento a nivel subtrocantérico. Los pacientes han sido evaluados pre y post-operatoriamente tanto desde el punto de vista radiográfico como clínico. Desde el punto de vista clínico, se obtuvieron 8 resultados excelentes, 3 buenos, 1 discreto y 1 malo. Todos los pacientes estaban plenamente satisfechos con el resultado de la operación habiendo aumentado drásticamente su nivel de actividad. Solamente en un caso fue necesario practicar una intervención de revisión a los 4 años de la artroplastia primitiva, a causa de una grave osificación periprotésica. Solamente se tuvo una complicación intraoperatoria consistente en una fractura de la diálisis femoral.Thirteen non-cemented hips prostheses implanted in 12 patients with an osteoartritis secundar y to congenita l dislocation and dysplasi a of the hip wer e reviewed . Patients had a more than 2 years follow-up. The postero-lateral surgical approach was employed in all cases. On the acetabular side, we always used the PCA socket type. On the femoral side we implanted a PCA standard stem in 7 cases, mid stem in 3 cases and a long stem in 3. Acetabular bone autograft was added in 7 patients. In order to restore the original center of rotacion of the hip, in patients with a severe dislocation we perfomed also a shortening sub-trochanteric osteotomy; all the patients wer e evaluated pre and post-operatively with two separate forms. The first regarding the clinical evaluation, the second for radiographic assessment. All the patients were fully satisfied with the operation increasing dramatically their activity level. We obtained 8 excellent results, 3 good, 1 fair and 1 poor. One case required a revision for a severe heterotopic bone formation about 4 years after the first implant. We had a diaphyseal femoral fracture as the sole inly an intraoperative complication

Building capacity in remote sensing for conservation: present and future challenges

Remote sensing (RS) has made significant contributions to conservation and ecology; however, direct use of RS-based information for conservation decision making is currently very limited. In this paper, we discuss the reasons and challenges associated with using RS technology by conservationists and suggest how training in RS for conservationists can be improved. We present the results from a survey organized by the Conservation Remote Sensing Network to understand the RS expertise and training needs of various categories of professionals involved in conservation research and implementation. The results of the survey highlight the main gaps and priorities in the current RS data and technology among conservation practitioners from academia, institutions, NGOs and industry. We suggest training to be focused around conservation questions that can be addressed using RS-derived information rather than training pure RS methods which are beyond the interest of conservation practitioners. We highlight the importance of developing essential biodiversity variables (EBVs) and how this can be achieved by increasing the RS capacity of the conservation community. Moreover, we suggest that open-source software is adopted more widely in the training modules to facilitate access to RS data and products in developing countries, and that online platforms providing mapping tools should also be more widely distributed. We believe that improved RS capacity among conservation scientists will be essential to improve conservation efforts on the ground and will make the conservation community a key player in the definition of future RS-based products that serve conservation and ecological needs

Link Adaptation for Mitigating Earth-To-Space Propagation Effects on the NASA SCaN Testbed

In Earth-to-Space communications, well-known propagation effects such as path loss and atmospheric loss can lead to fluctuations in the strength of the communications link between a satellite and its ground station. Additionally, the typically unconsidered effect of shadowing due to the geometry of the satellite and its solar panels can also lead to link degradation. As a result of these anticipated channel impairments, NASA's communication links have been traditionally designed to handle the worst-case impact of these effects through high link margins and static, lower rate, modulation formats. The work presented in this paper aims to relax these constraints by providing an improved trade-off between data rate and link margin through utilizing link adaptation. More specifically, this work provides a simulation study on the propagation effects impacting NASA's SCaN Testbed flight software-defined radio (SDR) as well as proposes a link adaptation algorithm that varies the modulation format of a communications link as its signal-to-noise ratio fluctuates. Ultimately, the models developed in this work will be utilized to conduct real-time flight experiments on-board the NASA SCaN Testbed

The effects of monocytes on tumor cell extravasation in a 3D vascularized microfluidic model

Metastasis is the leading cause of cancer-related deaths. Recent developments in cancer immunotherapy have shown exciting therapeutic promise for metastatic patients. While most therapies target T cells, other immune cells, such as monocytes, hold great promise for therapeutic intervention. In our study, we provide primary evidence of direct engagement between human monocytes and tumor cells in a 3D vascularized microfluidic model. We first characterize the novel application of our model to investigate and visualize at high resolution the evolution of monocytes as they migrate from the intravascular to the extravascular micro-environment. We also demonstrate their differentiation into macrophages in our all-human model. Our model replicates physiological differences between different monocyte subsets. In particular, we report that inflammatory, but not patrolling, monocytes rely on actomyosin based motility. Finally, we exploit this platform to study the effect of monocytes, at different stages of their life cycle, on cancer cell extravasation. Our data demonstrates that monocytes can directly reduce cancer cell extravasation in a non-contact dependent manner. In contrast, we see little effect of monocytes on cancer cell extravasation once monocytes transmigrate through the vasculature and are macrophage-like. Taken together, our study brings novel insight into the role of monocytes in cancer cell extravasation, which is an important step in the metastatic cascade. These findings establish our microfluidic platform as a powerful tool to investigate the characteristics and function of monocytes and monocyte-derived macrophages in normal and diseased states. We propose that monocyte-cancer cell interactions could be targeted to potentiate the anti-metastatic effect we observe in vitro, possibly expanding the milieu of immunotherapies available to tame metastasis

Subcutaneous Haemangiosarcoma in a Cockatiel ( Nymphicus hollandicus )

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74932/1/j.1439-0442.2006.00825.x.pd

Direct Observation of Martensitic Phase-Transformation Dynamics in Iron by 4D Single-Pulse Electron Microscopy

The in situ martensitic phase transformation of iron, a complex solid-state transition involving collective atomic displacement and interface movement, is studied in real time by means of four-dimensional (4D) electron microscopy. The iron nanofilm specimen is heated at a maximum rate of ∼10^(11) K/s by a single heating pulse, and the evolution of the phase transformation from body-centered cubic to face-centered cubic crystal structure is followed by means of single-pulse, selected-area diffraction and real-space imaging. Two distinct components are revealed in the evolution of the crystal structure. The first, on the nanosecond time scale, is a direct martensitic transformation, which proceeds in regions heated into the temperature range of stability of the fcc phase, 1185−1667 K. The second, on the microsecond time scale, represents an indirect process for the hottest central zone of laser heating, where the temperature is initially above 1667 K and cooling is the rate-determining step. The mechanism of the direct transformation involves two steps, that of (barrier-crossing) nucleation on the reported nanosecond time scale, followed by a rapid grain growth typically in ∼100 ps for 10 nm crystallites

A Preparative Method for the Isolation and Fractionation of Dissolved Organic Acids from Bitumen-influenced Waters

The surface mining of oil sands north of Fort McMurray, Alberta produces considerable tailings waste that is stored in large tailings ponds on industrial lease sites. Viable strategies for the detoxification of oil sands process affected water (OSPW) are under investigation. In order to assess the toxic potential of the suite of dissolved organics in OSPW, a method for their extraction and fractionation was developed using solid phase extraction. The method successfully isolated organic compounds from 180 L of an aged OSPW source. Using acidic- or alkaline-conditioned non-polar ENV+ resin and soxhlet extraction with ethyl acetate and methanol, three fractions (F1–F3) were generated. Chemical characterization of the generated fractions included infusion to electrospray ionization ultrahigh-resolution mass spectrometry (ESI-UHRMS), liquid chromatography quadrupole time-of-flight mass spectrometry, gas chromatography triple quadrupole time-of-flight mass spectrometry, and synchronous fluorescence spectroscopy (SFS). Additionally, ESI-UHRMS class distribution data and SFS identified an increased degree of oxygenation and aromaticity, associated with increased polarity. Method validation, which included method and matrix spikes with surrogate and labelled organic mono carboxylic acid standards, confirmed separation according to acidity and polarity with generally good recoveries (average 76%). Because this method is capable of extracting large sample volumes, it is amenable to thorough chemical characterization and toxicological assessments with a suite of bioassays. As such, this protocol will facilitate effects-directed analysis of toxic components within bitumen-influenced waters from a variety of sources

Neurogranin as a predictor of memory and executive function decline in MCI patients

Objective To determine whether high CSF levels of neurogranin (Ng) predict longitudinal decline in memory and executive function during early-stage Alzheimer disease (AD). Methods Baseline levels of CSF Ng were studied in relation to cross-sectional and longitudinal cognitive performance over 8 years. Data were obtained from the Alzheimer's Disease Neuroimaging Initiative database, and participants with normal cognition (n = 111) and mild cognitive impairment (MCI) (n = 193) were included. Results High levels of CSF Ng were associated with poor baseline memory scores (β = −0.21, p < 0.0001). CSF Ng predicted both memory and executive function decline over time (β = −0.0313, p = 0.0068 and β = −0.0346, p = 0.0169, respectively) independently of age, sex, education, and APOE ε4 status. When the rate of decline by tertiles was examined, CSF Ng was a level-dependent predictor of memory function, whereby the group with highest levels of Ng showed the fastest rates of decline in both memory and executive function. When examined separately, elevated Ng was associated with cognitive decline in participants with MCI but not in those with normal cognition. The levels of CSF Ng were not associated with cognitive measures when tau and amyloid 42 (Aβ42) were controlled for in these analyses. Conclusions High CSF Ng associates with poor memory scores in participants with MCI cross-sectionally and with poor memory and executive function longitudinally. The association of Ng with cognitive measures disappears when tau and Aβ42 are included in the statistical models. Our findings suggest that CSF Ng may serve as a biomarker of cognition. Synaptic dysfunction contributes to cognitive impairment in early-stage AD