Double Opposing-Rhomboid Flaps for Closure of a Circular Facial Defect in a Special Position

Various techniques are used to repair circular defects in special positions on the face. Simple closure will yield unsatisfactory results because of skin tension. As an ideal method of reconstruction, various flaps are used to provide a versatile and safe alternative. The authors applied double opposing-rhomboid flaps, which provided for closure of a circular skin defect without alteration to the original shapes of the vital structures and resulted in an imperceptible scar. With careful designing, 21 patients with circular defects caused by skin tumor excisions to special facial positions have attained effective functional and aesthetic results using this method since 2004

Comparative analysis of machine learning algorithms for multi-syndrome classification of neurodegenerative syndromes

Importance: The entry of artificial intelligence into medicine is pending. Several methods have been used for the predictions of structured neuroimaging data, yet nobody compared them in this context. Objective: Multi-class prediction is key for building computational aid systems for differential diagnosis. We compared support vector machine, random forest, gradient boosting, and deep feed-forward neural networks for the classification of different neurodegenerative syndromes based on structural magnetic resonance imaging. Design, setting, and participants: Atlas-based volumetry was performed on multi-centric T1-weighted MRI data from 940 subjects, i.e., 124 healthy controls and 816 patients with ten different neurodegenerative diseases, leading to a multi-diagnostic multi-class classification task with eleven different classes. Interventions: N.A. Main outcomes and measures: Cohen's kappa, accuracy, and F1-score to assess model performance. Results: Overall, the neural network produced both the best performance measures and the most robust results. The smaller classes however were better classified by either the ensemble learning methods or the support vector machine, while performance measures for small classes were comparatively low, as expected. Diseases with regionally specific and pronounced atrophy patterns were generally better classified than diseases with widespread and rather weak atrophy. Conclusions and relevance: Our study furthermore underlines the necessity of larger data sets but also calls for a careful consideration of different machine learning methods that can handle the type of data and the classification task best

The structure of spray-dried detergent powders

The complex multi-scale structure of spray-dried detergent granules has been characterized using a range of techniques including microscopy, wide-angle and small-angle X-ray scattering and X-ray microtomography. Four simple model formulations based on linear alkyl benzene sulphonate (NaLAS) and sodium sulphate were used to probe the influence of initial slurry water content and sodium silicate on the structure. The structure can be viewed as a porous matrix consisting of liquid crystalline NaLAS, sodium sulphate and binder in which large crystals of sodium sulphate are embedded. These large crystals were initially undissolved in the slurry and are consequently reduced in number in the product made from higher water content slurry. The both slurry water content and sodium silicate changed the polymorphs, and the d-spacing of the lamellae. The surface micro-structure and particle morphology can also be significantly affected with the high initial water content; particles having a distinct agglomerated and blistered structure

Photothermal treatment of glioma; an in vitro study of macrophage-mediated delivery of gold nanoshells

One of the major factors that limits the treatment effectiveness for gliomas is the presence of the blood–brain barrier (BBB) which protects infiltrating glioma cells from the effects of anti-cancer agents. Circulating monocytes/macrophages (Ma) have a natural ability to traverse the intact and compromised BBB and loaded with anti cancer agents could be used as vectors to target tumors and surrounding tumor infiltrated tissue. Nanoshells (NS) are composed of a dielectric core (silica) coated with an ultrathin gold layer which converts absorbed near-infrared light (NIR) to heat with an extremely high efficacy and stability. We have investigated the effects of exposure to laser NIR on multicell human glioma spheroids infiltrated with empty (containing no nanoshells) or nanoshell loaded macrophages. Our results demonstrated that; (1) macrophages could efficiently take up bare or coated (PEGylated) gold NS: (2) NS loaded macrophages infiltrated into glioma spheroids to the same or, in some cases, to a greater degree than empty Ma; (3) NIR laser irradiation of spheroids incorporating NS loaded macrophages resulted in complete growth inhibition in an irradiance dependent manner, and (4) spheroids infiltrated with empty macrophages had growth curves identical to untreated control cultures. The results of this study provide proof of concept for the use of macrophages as a delivery vector of NS into gliomas for photothermal ablation and open the possibility of developing such regimens for patient treatment

O ensino das ciências experimentais no liceu, em Portugal, na I República (1910-1926)

O ensino das ciências experimentais (ECE) em Portugal ficou, como pretendemos demonstrar, fortemente marcado pela instauração da República, que comemorou no ano transacto o seu centenário. A República de 1910 pretendeu reformar toda a mentalidade portuguesa, através do pilar base – a educação – pela qual seria capaz de sacudir a nossa maneira de ser, lançando desta forma o país para um progresso de nível europeu. O estudo a que nos propomos, uma investigação documental no domínio da História da Ciência1, visa aprofundar os conhecimentos existentes sobre esta época e perceber o impacto da reforma do ECE, principalmente nos Liceus, caracterizando as principais figuras, políticas e docentes responsáveis pela sua conceptualização e aplicação. Através desta investigação procuraremos lançar as primeiras bases para descobrir as origens deste pensamento, querendo ainda comparar os fundamentos psicopedagógicos, epistemológicos e sociológicos da época com as principais ideias actualmente presentes no ensino da Ciência. Com este trabalho pretendemos, num primeiro momento, apresentar e divulgar o desenho da investigação e os seus objectivos, na procura de estabelecer parcerias e receber contributos da comunidade académica interessada por esta problemática

In silico Experimentation of Glioma Microenvironment Development and Anti-tumor Therapy

Tumor cells do not develop in isolation, but co-evolve with stromal cells and tumor-associated immune cells in a tumor microenvironment mediated by an array of soluble factors, forming a complex intercellular signaling network. Herein, we report an unbiased, generic model to integrate prior biochemical data and the constructed brain tumor microenvironment in silico as characterized by an intercellular signaling network comprising 5 types of cells, 15 cytokines, and 69 signaling pathways. The results show that glioma develops through three distinct phases: pre-tumor, rapid expansion, and saturation. We designed a microglia depletion therapy and observed significant benefit for virtual patients treated at the early stages but strikingly no therapeutic efficacy at all when therapy was given at a slightly later stage. Cytokine combination therapy exhibits more focused and enhanced therapeutic response even when microglia depletion therapy already fails. It was further revealed that the optimal combination depends on the molecular profile of individual patients, suggesting the need for patient stratification and personalized treatment. These results, obtained solely by observing the in silico dynamics of the glioma microenvironment with no fitting to experimental/clinical data, reflect many characteristics of human glioma development and imply new venues for treating tumors via selective targeting of microenvironmental components

Dynamic Predictive Modeling Under Measured and Unmeasured Continuous-Time Stochastic Input Behavior

Many input variables of chemical processes have a continuous-time stochastic (CTS) behavior. The nature of these variables is a persistent, time-correlated variation that manifests as process variation as the variables deviate in time from their nominal levels. This work introduces methodologies in process identification for improving the modeling of process outputs by exploiting CTS input modeling under cases where the input is measured and unmeasured. In the measured input case, the output variable is measured offline, infrequently, and at a varying sampling rate. A method is proposed for estimating CTS parameters from the measured input by exploiting statistical properties of its CTS model. The proposed approach is evaluated based on both output accuracy and predictive ability several steps ahead of the current input measurement. Two parameter estimation techniques are proposed when the input is unmeasured. The first is a derivative-free approach that uses sample moments and analytical expressions for population moments to estimate the CTS model parameters. The second exploits the CTS input model and uses the analytical solution of the dynamic model to estimate these parameters. The predictive ability of the latter approach is evaluated in the same way as the measured input case. All of the data in this work were artificially generated under the probabilistic CTS model.Reprinted (adapted) with permission from Industrial and Engineering Chemistry Research 51 (2012): 5469, doi: 10.1021/ie201998b. Copyright 2012 American Chemical Society.</p

Diffuse glioma growth: a guerilla war

In contrast to almost all other brain tumors, diffuse gliomas infiltrate extensively in the neuropil. This growth pattern is a major factor in therapeutic failure. Diffuse infiltrative glioma cells show some similarities with guerilla warriors. Histopathologically, the tumor cells tend to invade individually or in small groups in between the dense network of neuronal and glial cell processes. Meanwhile, in large areas of diffuse gliomas the tumor cells abuse pre-existent “supply lines” for oxygen and nutrients rather than constructing their own. Radiological visualization of the invasive front of diffuse gliomas is difficult. Although the knowledge about migration of (tumor)cells is rapidly increasing, the exact molecular mechanisms underlying infiltration of glioma cells in the neuropil have not yet been elucidated. As the efficacy of conventional methods to fight diffuse infiltrative glioma cells is limited, a more targeted (“search & destroy”) tactic may be needed for these tumors. Hopefully, the study of original human glioma tissue and of genotypically and phenotypically relevant glioma models will soon provide information about the Achilles heel of diffuse infiltrative glioma cells that can be used for more effective therapeutic strategies

Under-vaccinated groups in Europe and their beliefs, attitudes and reasons for non-vaccination; two systematic reviews

BackgroundDespite effective national immunisation programmes in Europe, some groups remain incompletely or un-vaccinated ('under-vaccinated'), with underserved minorities and certain religious/ideological groups repeatedly being involved in outbreaks of vaccine preventable diseases (VPD). Gaining insight into factors regarding acceptance of vaccination of 'under-vaccinated groups' (UVGs) might give opportunities to communicate with them in a trusty and reliable manner that respects their belief system and that, maybe, increase vaccination uptake. We aimed to identify and describe UVGs in Europe and to describe beliefs, attitudes and reasons for non-vaccination in the identified UVGs.MethodsWe defined a UVG as a group of persons who share the same beliefs and/or live in socially close-knit communities in Europe and who have/had historically low vaccination coverage and/or experienced outbreaks of VPDs since 1950. We searched MEDLINE, EMBASE and PsycINFO databases using specific search term combinations. For the first systematic review, studies that described a group in Europe with an outbreak or low vaccination coverage for a VPD were selected and for the second systematic review, studies that described possible factors that are associated with non-vaccination in these groups were selected.ResultsWe selected 48 articles out of 606 and 13 articles out of 406 from the first and second search, respectively. Five UVGs were identified in the literature: Orthodox Protestant communities, Anthroposophists, Roma, Irish Travellers, and Orthodox Jewish communities. The main reported factors regarding vaccination were perceived non-severity of traditional "childhood" diseases, fear of vaccine side-effects, and need for more information about for example risk of vaccination.ConclusionsWithin each UVG identified, there are a variety of health beliefs and objections to vaccination. In addition, similar factors are shared by several of these groups. Communication strategies regarding these similar factors such as educating people about the risks associated with being vaccinated versus not being vaccinated, addressing their concerns, and countering vaccination myths present among members of a specific UVG through a trusted source, can establish a reliable relationship with these groups and increase their vaccination uptake. Furthermore, other interventions such as improving access to health care could certainly increase vaccination uptake in Roma and Irish travellers