Transplant arteriosclerosis: an enigmatic disease due to a misnomer

Solid organ transplantation across the allogeneic barrier, pioneered by Thomas Starzl, has by now become a common medical procedure. Unfortunately, the number of donor organs lost due to transplant arteriosclerosis (chronic rejection), remains significant and unchanged for decades. We argue that designation of transplant arteriosclerosis as chronic rejection, and its classification as a delayed long-lasting reaction of recipient immune effectors against donor alloantigens have given us a wrong impression that we have identified the necessary cause/pathogenesis of the tissue pathology. However, whatever treatment options we have in the anti-rejection toolbox, despite their success in treating classical rejection, do not work for the transplant arteriosclerosis. Yet, the scientific community has continued to conceptualize and approach the pathology within the alloimmunity model. Due to unproductive research from the alloimmunity and rejection perspective, the number of transplanted hearts lost due to this pathology today is almost the same as it was fifty years ago. We believe that this phenomenon falls under the rubric of linguistic relativity, and that language we chose to name the disease has restricted our cognitive ability to solve the problem. While the initial perception of the transplant arteriosclerosis as chronic rejection was logical and scientific, the subsequent experience revealed that such perception and approach have been fruitless, and likely are incorrect. Considering our tragic failure to prevent and treat the delayed arterial pathology of donor organs using all available knowledge on alloimmunity and rejection, we must finally disassociate the former from the latter. The only way to start this uncomfortable process is to change the words we are using; particularly, the words we chose to name the disease. We have to step out of the alloimmunity rejection box.Comment: 19 pages, 2 figure

Effect of liver transplantation on inflammatory bowel disease in patients with primary sclerosing cholangitis

This report investigates the influence of liver transplantation and concomitant immunosuppression on the course of progression of inflammatory bowel disease (IBD) and discusses statistical methodology appropriate for such settings. The data on 303 patients who underwent liver transplantation for primary sclerosing cholangitis (PSC) were analyzed using person-time analysis and Cox regression, with the duration of IBD as the time variable and transplantation as a segmented time-dependent covariate, to take into account both posttransplant and pretransplant history of IBD. The need for colectomy and appearance of colorectal cancer were taken as outcome measures. The only significant risk factor in the multivariate model for colectomy was transplantation itself, which increased the risk of colectomy due to intractable disease (Wald statistic; P =. 001). None of the variables available for analysis were found to influence the risk of colon cancer significantly. Graphs showing the dependence of the instantaneous risk of cancer on the time from onset of IBD and its independence from the latter in the case of colectomy are presented. The use of a unique statistical methodology described for the first time in this setting led us to the somewhat surprising conclusion that transplantation and concomitant use of immunosuppression accelerate the progression of IBD. At the same time, transplantation does not affect the incidence of colorectal cancer. These results confirm the findings of some recent studies and can potentially shed new light on the disease pathogenesis

Predicting Multiple ICD-10 Codes from Brazilian-Portuguese Clinical Notes

ICD coding from electronic clinical records is a manual, time-consuming and expensive process. Code assignment is, however, an important task for billing purposes and database organization. While many works have studied the problem of automated ICD coding from free text using machine learning techniques, most use records in the English language, especially from the MIMIC-III public dataset. This work presents results for a dataset with Brazilian Portuguese clinical notes. We develop and optimize a Logistic Regression model, a Convolutional Neural Network (CNN), a Gated Recurrent Unit Neural Network and a CNN with Attention (CNN-Att) for prediction of diagnosis ICD codes. We also report our results for the MIMIC-III dataset, which outperform previous work among models of the same families, as well as the state of the art. Compared to MIMIC-III, the Brazilian Portuguese dataset contains far fewer words per document, when only discharge summaries are used. We experiment concatenating additional documents available in this dataset, achieving a great boost in performance. The CNN-Att model achieves the best results on both datasets, with micro-averaged F1 score of 0.537 on MIMIC-III and 0.485 on our dataset with additional documents.Comment: Accepted at BRACIS 202

Заходи щодо забезпечення фізичної безпеки людей і об'єктів у разі загрози «вибухового тероризму»

Суботін, А. О. Заходи щодо забезпечення фізичної безпеки людей і об'єктів у разі загрози «вибухового тероризму» / А. О. Суботін, О. П. Мірошко, Є. А. Пальваль, М. В. Вус // Вісник Харківського національного університету внутрішніх справ. - 2008. - Вип. 41. - С. 169-173.В статті досліджена проблема найпоширеного прояву тероризму – «вибухового тероризму». Розглянуто питання забезпечення фізичної безпеки людей і об’єктів у разі загрози «вибухового терроризму». В статье исследована проблема наиболее распространенного проявления терроризма - «взрывного терроризма». Рассмотрены вопросы обеспечения физической безопасности людей и объектов в случае угрозы «взрывного терроризма». The article explores the problem of the most common manifestation of terrorism - "explosive terrorism". The issue of physical security of people and objects in case of threat of "explosive terrorism" is considered

Analysis of arterial intimal hyperplasia: review and hypothesis

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background: Despite a prodigious investment of funds, we cannot treat or prevent arteriosclerosis and restenosis, particularly its major pathology, arterial intimal hyperplasia. A cornerstone question lies behind all approaches to the disease: what causes the pathology? Hypothesis: I argue that the question itself is misplaced because it implies that intimal hyperplasia is a novel pathological phenomenon caused by new mechanisms. A simple inquiry into arterial morphology shows the opposite is true. The normal multi-layer cellular organization of the tunica intima is identical to that of diseased hyperplasia; it is the standard arterial system design in all placentals at least as large as rabbits, including humans. Formed initially as one-layer endothelium lining, this phenotype can either be maintained or differentiate into a normal multi-layer cellular lining, so striking in its resemblance to diseased hyperplasia that we have to name it "benign intimal hyperplasia". However, normal or "benign " intimal hyperplasia, although microscopically identical to pathology, is a controllable phenotype that rarely compromises blood supply. It is remarkable that each human heart has coronary arteries in which a single-layer endothelium differentiates earl

Performance of Multi-Layer Feedforward Neural Networks to Predict Liver Transplantation Outcome

AbstractA novel multisolutional clustering and quantization (MCO) algorithm has been developed that provides a flexible way to preprocess data. It was tested whether it would impact the neural network’s performance favorably and whether the employment of the proposed algorithm would enable neural networks to handle missing data. This was assessed by comparing the performance of neural networks using a well-documented data set to predict outcome following liver transplantation. This new approach to data preprocessing leads to a statistically significant improvement in network performance when compared to simple linear scaling. The obtained results also showed that coding missing data as zeroes in combination with the MCO algorithm, leads to a significant improvement in neural network performance on a data set containing missing values in 59.4% of cases when compared to replacement of missing values with either series means or medians.</jats:p

Effect of 3D Shape of Pump-Turbine Runner Blade on Flow Characteristics in Turbine Mode

The effect of blade spatial profiling with the help of tangential blade lean of Francis pump-turbine runner with heads up to 200 m on the flow structure and energy characteristics was numerically investigated. A flow part model of Francis pump-turbine of the Dniester pumped storage plant was adopted as original version. Two new blade systems were designed, which differed from the original version by mutual position of cross-sections in tangential direction: with positive and negative lean, while the shape of the cross-sections themselves remained unchanged. Modeling of the viscous incompressible flow in calculation domain, which contains one channel of the guide vane and the runner, for three variants of flow parts, was performed using the IPMFlow software based on numerical integration of the Reynolds equations with an additional term containing artificial compressibility. To take into account the turbulent effects, the SST differential two-parameter turbulence model of Menter is applied. Numerical integration of the equations is carried out using an implicit quasi-monotonic Godunov scheme of second order accuracy in space and time. The study was carried out for models with runner diameter of 350 mm in a wide range of guide vane openings at reduced rotation frequencies corresponding to the minimal, design and maximal heads of the station. A comparison of pressure fields and velocity vectors in the runners, pressure graphs on runner blades, distribution of velocity components at inlet to a draft tube, and efficiency of three variants of flow parts are presented. It was concluded that calculation domain with the new RK5217M2 runner with negative tangential lean has the best characteristics. An experimental study of three runners on a hydrodynamic stand are planned