Forensic analysis of ephemeral messaging applications: Disappearing messages or evidential data?

Ephemeral messaging or ‘disappearing messages’ is the mobile-to-mobile transmission of multimedia messages that automatically disappear from the recipient's screen after the message has been viewed. This new feature can be enabled by users for more privacy when using instant messaging apps. A user can set messages to disappear within a certain timeframe: 24 hours, 7 days, or 90 days, after the time they are sent. While disappearing messages provide additional privacy to users, its anti-forensics capability creates challenges for investigators in the recovery of evidential artefacts that could be crucial to an investigation. In this paper, we conduct a comprehensive forensic analysis of ‘disappearing messages’ across different digital platforms (mobile, desktop, and cloud) and instant messaging apps (WhatsApp, Snapchat, and Telegram) to determine whether they can be recovered within a limited timeframe. The results from this study provide valuable information to investigators dealing with instant messaging apps that have this feature enabled and provides detailed understanding of how disappearing messages are stored, managed, and deleted compared to messages sent without this feature enabled

Resistance to Mucosal Lysozyme Compensates for the Fitness Deficit of Peptidoglycan Modifications by Streptococcus pneumoniae

The abundance of lysozyme on mucosal surfaces suggests that successful colonizers must be able to evade its antimicrobial effects. Lysozyme has a muramidase activity that hydrolyzes bacterial peptidoglycan and a non-muramidase activity attributable to its function as a cationic antimicrobial peptide. Two enzymes (PgdA, a N-acetylglucosamine deacetylase, and Adr, an O-acetyl transferase) that modify different sites on the peptidoglycan of Streptococcus pneumoniae have been implicated in its resistance to lysozyme in vitro. Here we show that the antimicrobial effect of human lysozyme is due to its muramidase activity and that both peptidoglycan modifications are required for full resistance by pneumococci. To examine the contribution of lysozyme and peptidoglycan modifications during colonization of the upper respiratory tract, competition experiments were performed with wild-type and pgdAadr mutant pneumococci in lysozyme M-sufficient (LysM+/+) and -deficient (LysM−/−) mice. The wild-type strain out-competed the double mutant in LysM+/+, but not LysM−/− mice, indicating the importance of resistance to the muramidase activity of lysozyme during mucosal colonization. In contrast, strains containing single mutations in either pgdA or adr prevailed over the wild-type strain in both LysM+/+ and LysM−/− mice. Our findings demonstrate that individual peptidoglycan modifications diminish fitness during colonization. The competitive advantage of wild-type pneumococci in LysM+/+ but not LysM−/− mice suggests that the combination of peptidoglycan modifications reduces overall fitness, but that this is outweighed by the benefits of resistance to the peptidoglycan degrading activity of lysozyme

Antimicrobial proteins and polypeptides in pulmonary innate defence

Inspired air contains a myriad of potential pathogens, pollutants and inflammatory stimuli. In the normal lung, these pathogens are rarely problematic. This is because the epithelial lining fluid in the lung is rich in many innate immunity proteins and peptides that provide a powerful anti-microbial screen. These defensive proteins have anti-bacterial, anti- viral and in some cases, even anti-fungal properties. Their antimicrobial effects are as diverse as inhibition of biofilm formation and prevention of viral replication. The innate immunity proteins and peptides also play key immunomodulatory roles. They are involved in many key processes such as opsonisation facilitating phagocytosis of bacteria and viruses by macrophages and monocytes. They act as important mediators in inflammatory pathways and are capable of binding bacterial endotoxins and CPG motifs. They can also influence expression of adhesion molecules as well as acting as powerful anti-oxidants and anti-proteases. Exciting new antimicrobial and immunomodulatory functions are being elucidated for existing proteins that were previously thought to be of lesser importance. The potential therapeutic applications of these proteins and peptides in combating infection and preventing inflammation are the subject of ongoing research that holds much promise for the future

Vitamin D nutrition in pregnancy: current opinion

Adekunle Dawodu,1 Henry Akinbi21Global Health Center, 2Neonatology and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USAAbstract: There is increasing interest in vitamin D nutrition during pregnancy because of widespread reports of a high prevalence of low vitamin D status in pregnant women. While vitamin D is important for calcium and phosphorus homeostasis and for bone health, it also plays important roles in many other physiologic functions in the body. Consistent with the expanded role of vitamin D, recent observational studies have demonstrated that low vitamin D status in pregnancy is associated with multiple potential adverse maternal, fetal, and infant outcomes and contributes to low vitamin D status in infants at birth. Therefore, an overview of the current understanding of vitamin D nutrition in pregnancy and a review of the results of studies to optimize vitamin D status during pregnancy and in the offspring is of public health importance and timely.Keywords: vitamin D, pregnancy, neonat

Disappearing Messages: Privacy or Piracy?

The Telegram instant messenger application is a rival and alternative to the popular messaging application WhatsApp, with both applications citing end-to-end encryption for both messages and calls as a key offering. While Telegram doesn't officially have a ‘disappearing message' feature like WhatsApp it still is possible to send disappearing messages using the secret chat functionality. In this paper we analyse and evaluate ‘disappearing messages' across Telegram and Snapchat to see whether they can be forensically preserved and/or recovered across iOS and Android operating systems. As these messages could be vital to investigations, with potential evidence and intelligence stored on them, not to mention the limited timeframe in which they are ‘viewable' to the user, it is a great opportunity for Digital Forensics to understand how they are stored, managed, and ‘deleted' compared to traditional messages on the same platforms/applications