Universal lung epithelium DNA methylation markers for detection of lung damage in liquid biopsies.

BACKGROUND: Circulating biomarkers for lung damage are lacking. Lung epithelium-specific DNA methylation patterns can potentially report the presence of lung-derived cell-free DNA (cfDNA) in blood, as an indication of lung cell death. METHODS: We sorted human lung alveolar and bronchial epithelial cells from surgical specimens, and obtained their methylomes using whole-genome bisulfite sequencing. We developed a PCR sequencing assay determining the methylation status of 17 loci with lung-specific methylation patterns, and used it to assess lung-derived cfDNA in the plasma of healthy volunteers and patients with lung disease. RESULTS: Loci that are uniquely unmethylated in alveolar or bronchial epithelial cells are enriched for enhancers controlling lung-specific genes. Methylation markers extracted from these methylomes revealed that normal lung cell turnover probably releases cfDNA into the air spaces, rather than to blood. People with advanced lung cancer show a massive elevation of lung cfDNA concentration in blood. Among individuals undergoing bronchoscopy, lung-derived cfDNA is observed in the plasma of those later diagnosed with lung cancer, and to a lesser extent in those diagnosed with other lung diseases. Lung cfDNA is also elevated in patients with acute exacerbation of COPD compared with patients with stable disease, and is associated with future exacerbation and mortality in these patients. CONCLUSIONS: Universal cfDNA methylation markers of normal lung epithelium allow for mutation-independent, sensitive and specific detection of lung-derived cfDNA, reporting on ongoing lung injury. Such markers can find broad utility in the study of normal and pathologic human lung dynamics.

ASSAF: Advanced and Slim StegAnalysis Detection Framework for JPEG images based on deep convolutional denoising autoencoder and Siamese networks.

Steganography is the art of embedding a confidential message within a host message. Modern steganography is focused on widely used multimedia file formats, such as images, video files, and Internet protocols. Recently, cyber attackers have begun to include steganography (for communication purposes) in their arsenal of tools for evading detection. Steganalysis is the counter-steganography domain which aims at detecting the existence of steganography within a host file. The presence of steganography in files raises suspicion regarding the file itself, as well as its origin and receiver, and might be an indication of a sophisticated attack. The JPEG file format is one of the most popular image file formats and thus is an attractive and commonly used carrier for steganography embedding. State-of-the-art JPEG steganalysis methods, which are mainly based on neural networks, are limited in their ability to detect sophisticated steganography use cases. In this paper, we propose ASSAF, a novel deep neural network architecture composed of a convolutional denoising autoencoder and a Siamese neural network, specially designed to detect steganography in JPEG images. We focus on detecting the J-UNIWARD method, which is one of the most sophisticated adaptive steganography methods used today. We evaluated our novel architecture using the BOSSBase dataset, which contains 10,000 JPEG images, in eight different use cases which combine different JPEG's quality factors and embedding rates (bpnzAC). Our results show that ASSAF can detect stenography with high accuracy rates, outperforming, in all eight use cases, the state-of-the-art steganalysis methods by 6% to 40%.

Spondylodiskitis and endocarditis due to Streptococcus gordonii.

BACKGROUND: Streptococcus gordonii is an infrequent cause of infective endocarditis (IE); associated spondylodiskitis has not yet been described in the literature. PURPOSE: We describe 2 patients who presented with new-onset, severe back pain; blood cultures revealed S. gordonii bacteremia, which led to the diagnosis of spondylodiskitis and IE. We review our 2-decade experience with S. gordonii bacteremia to describe the clinical and epidemiological characteristics of these patients. RESULTS: In our hospital over the last 20 years (1998-2017), a total of 15 patients with S. gordonii bacteremia were diagnosed, including 11 men and 4 women, and the mean age was 65 ± 22 (range 23-95). The most common diagnosis was IE (9 patients), spondylodiskitis (the presented 2 patients, who in addition were diagnosed with endocarditis), necrotizing fasciitis (1), sternitis (1), septic arthritis (1) and pneumonia (1). The 11 patients with IE were treated with penicillin ± gentamicin, or ceftriaxone for 6 weeks, 5 required valve surgery and 10/11 (91%) attained complete cure. The 2 patients with diskitis required 2-3 months of intravenous antibiotics to achieve complete cure. CONCLUSION: Spondylodiskitis was the presenting symptom of 2/11 (18%) patients with S. gordonii endocarditis. Spondylodiskitis should probably be looked for in patients diagnosed with S. gordonii endocarditis and back pain as duration of antibiotic treatment to achieve complete cure may be considerably longer.

Memory based active contour algorithm using pixel-level classified images for colon crypt segmentation.

In this paper, we introduce a novel method for detection and segmentation of crypts in colon biopsies. Most of the approaches proposed in the literature try to segment the crypts using only the biopsy image without understanding the meaning of each pixel. The proposed method differs in that we segment the crypts using an automatically generated pixel-level classification image of the original biopsy image and handle the artifacts due to the sectioning process and variance in color, shape and size of the crypts. The biopsy image pixels are classified to nuclei, immune system, lumen, cytoplasm, stroma and goblet cells. The crypts are then segmented using a novel active contour approach, where the external force is determined by the semantics of each pixel and the model of the crypt. The active contour is applied for every lumen candidate detected using the pixel-level classification. Finally, a false positive crypt elimination process is performed to remove segmentation errors. This is done by measuring their adherence to the crypt model using the pixel level classification results. The method was tested on 54 biopsy images containing 4944 healthy and 2236 cancerous crypts, resulting in 87% detection of the crypts with 9% of false positive segments (segments that do not represent a crypt). The segmentation accuracy of the true positive segments is 96%.

Collapsing aged culture of the cyanobacterium Synechococcus elongatus produces compound(s) toxic to photosynthetic organisms.

Phytoplankton mortality allows effective nutrient cycling, and thus plays a pivotal role in driving biogeochemical cycles. A growing body of literature demonstrates the involvement of regulated death programs in the abrupt collapse of phytoplankton populations, and particularly implicates processes that exhibit characteristics of metazoan programmed cell death. Here, we report that the cell-free, extracellular fluid (conditioned medium) of a collapsing aged culture of the cyanobacterium Synechococcus elongatus is toxic to exponentially growing cells of this cyanobacterium, as well as to a large variety of photosynthetic organisms, but not to eubacteria. The toxic effect, which is light-dependent, involves oxidative stress, as suggested by damage alleviation by antioxidants, and the very high sensitivity of a catalase-mutant to the conditioned medium. At relatively high cell densities, S. elongatus cells survived the deleterious effect of conditioned medium in a process that required de novo protein synthesis. Application of conditioned medium from a collapsing culture caused severe pigment bleaching not only in S. elongatus cells, but also resulted in bleaching of pigments in a cell free extract. The latter observation indicates that the elicited damage is a direct effect that does not require an intact cell, and therefore, is mechanistically different from the metazoan-like programmed cell death described for phytoplankton. We suggest that S. elongatus in aged cultures are triggered to produce a toxic compound, and thus, this process may be envisaged as a novel regulated death program.

PTSD, resilience and posttraumatic growth among ex-prisoners of war and combat veterans.

BACKGROUND: Past studies have shown that adversity may yield various salutogenic outcomes. two constructs that have been at the center of this scientific investigation are resilience and posttraumatic growth (PTG). the present study aims to clarify the relations between posttraumatic stress symptoms, resilience and PTG among israeli war veterans. METHOD: the sample includes former prisoners of war (ex-POWs) (n=103) and comparable veterans (n=106) of the 1973 Yom Kippur War. the veterans were assessed twice: 18 and 30 years after the war with self-report questionnaires. RESULTS: resilience, defined as the absence of posttraumatic symptoms, and PTG are negatively correlated. resilient ex- POWs and veterans reported the lowest levels of PTG when compared to participants diagnosed with clinical and sub-clinical posttraumatic stress disorder (PtSd). Furthermore, PTG dimensions were found to be the most differentiating factor between study groups, followed by war exposure measures and clinical reports of depression and anxiety symptoms. CONCLUSIONS: this study strengthens the understanding that combatants who report high-level PtSd symptoms also report higher levels of positive psychological changes in the face of severe adversity.

PTSD symptoms, forgiveness, and revenge among Israeli Palestinian and Jewish adolescents.

Exposure to political terror and its psychological toll were assessed in 276 Israeli Palestinian and 1,469 Jewish adolescents using self-report questionnaires. Israeli Palestinians displayed more posttraumatic symptoms, higher levels of objective exposure to terror, more negative life events, lower ability to forgive, and a higher need for vengeance than their Jewish counterparts. Although the two groups did not differ in fear levels, Israeli Palestinians expressed more favorable attitudes toward peace. Ethnicity played a major role in explaining the variance of posttraumatic symptomatology. Israeli Palestinians displayed increased vulnerability to mental distress when compared to their Jewish counterparts. The unique roles of subjective fear, attitudes towards peace, forgiveness, and revenge among Israeli Palestinians are discussed.