In-situ PLL-g-PEG Functionalized Nanopore for Enhancing Protein Characterization

Single-molecule nanopore detection technology has revolutionized proteomics research by enabling highly sensitive and label-free detection of individual proteins. Herein, we designed a small, portable, and leak-free flowcell made of PMMA for nanopore experiments. In addition, we developed an in situ coating PLL-g-PEG approach to produce non-sticky nanopores for measuring the volume of diseases-relevant biomarker, such as the Alpha-1 antitrypsin (AAT) protein. The in situ coating method allows continuous monitoring, ensuring adequate coating, which can be directly used for translocation experiments. The coated nanopores exhibit improved characteristics, including an increased nanopore lifetime and enhanced translocation events of the AAT proteins. Furthermore, we demonstrated the reduction in the translocation event's dwell time, along with an increase in current blockade amplitudes and translocation numbers under different voltage stimuli. The study also successfully measures the single AAT protein volume (253 nm3 ), which closely aligns with the previously reported hydrodynamic volume. The real-time in situ PLL-g-PEG coating method and the developed nanopore flowcell hold great promise for various nanopores applications involving non-sticky single-molecule characterization

Psychosocial impact of undergoing prostate cancer screening for men with BRCA1 or BRCA2 mutations.

OBJECTIVES: To report the baseline results of a longitudinal psychosocial study that forms part of the IMPACT study, a multi-national investigation of targeted prostate cancer (PCa) screening among men with a known pathogenic germline mutation in the BRCA1 or BRCA2 genes. PARTICPANTS AND METHODS: Men enrolled in the IMPACT study were invited to complete a questionnaire at collaborating sites prior to each annual screening visit. The questionnaire included sociodemographic characteristics and the following measures: the Hospital Anxiety and Depression Scale (HADS), Impact of Event Scale (IES), 36-item short-form health survey (SF-36), Memorial Anxiety Scale for Prostate Cancer, Cancer Worry Scale-Revised, risk perception and knowledge. The results of the baseline questionnaire are presented. RESULTS: A total of 432 men completed questionnaires: 98 and 160 had mutations in BRCA1 and BRCA2 genes, respectively, and 174 were controls (familial mutation negative). Participants' perception of PCa risk was influenced by genetic status. Knowledge levels were high and unrelated to genetic status. Mean scores for the HADS and SF-36 were within reported general population norms and mean IES scores were within normal range. IES mean intrusion and avoidance scores were significantly higher in BRCA1/BRCA2 carriers than in controls and were higher in men with increased PCa risk perception. At the multivariate level, risk perception contributed more significantly to variance in IES scores than genetic status. CONCLUSION: This is the first study to report the psychosocial profile of men with BRCA1/BRCA2 mutations undergoing PCa screening. No clinically concerning levels of general or cancer-specific distress or poor quality of life were detected in the cohort as a whole. A small subset of participants reported higher levels of distress, suggesting the need for healthcare professionals offering PCa screening to identify these risk factors and offer additional information and support to men seeking PCa screening

Modelling the Optimal Link Length in Wireless Sensor Networks for Two Different Media Access Protocols

Conservation of energy is one of the main challenges in designing a wireless sensor network (WSN). The reason is that these large scaled networks cannot be arranged, configured, or maintained manually. Thus, automated deployment and configuration are required. One important factor determining the total energy consumption is the network topology. This article evaluates the relation between the maximum distance (link lengths) between the nodes in a WSN and the total energy consumed. The optimal topology for the two most commonly used medium access control (MAC) protocols were found. A WSN based on a Time Division Multiple Access (TDMA) protocol is limited by the maximum available or allowed emitted radio power. Thus, the criterion for optimal link lengths is related to the expected number of transmissions over the links. By including the retransmissions over the links we found an optimal internode distance. A Carrier Sense Multiple Access (CSMA) based WSN, on the other hand, is limited by the consumed energy of the overhearing nodes. In an analysis including only the overhearing nodes, the link lengths should be as short as possible and the connectivity of the network limits the link length used. However, we found that in a sparsely populated WSN, the total energy consumption increased for shorter link lengths as they were decreased from the optimal link length

Survey of Key Management in Ad Hoc Networks

The wireless and dynamic nature of mobile ad hoc networks (MANETs) leaves them more vulnerable to security attacks than their wired counterparts. The nodes act both as routers and as communication end points. This makes the network layer more prone to security attacks. A main challenge is to judge whether or not a routing message originates from a trustworthy node. The solution thus far is cryptographically signed messages. The general assumption is that nodes in possession of a valid secret key can be trusted. Consequently, a secure and efficient key-management scheme is crucial. Keys are also required for protection of application data. However, the focus here is on network-layer management information. Whereas keymanagement schemes for the upper layers can assume an already running network service, schemes for the protection of the network layer cannot. Keys are a prerequisite to bootstrap a protected network service. This article surveys the state of the art within key management for ad hoc networks, and analyzes their applicability for network-layer security. The analysis puts some emphasis on their applicability in scenarios such as emergency and rescue operations, as this work was initiated by a study of security in MANETs for emergency and rescue operations.acceptedVersio

Survey of Key Management in Ad Hoc Networks

The wireless and dynamic nature of mobile ad hoc networks (MANETs) leaves them more vulnerable to security attacks than their wired counterparts. The nodes act both as routers and as communication end points. This makes the network layer more prone to security attacks. A main challenge is to judge whether or not a routing message originates from a trustworthy node. The solution thus far is cryptographically signed messages. The general assumption is that nodes in possession of a valid secret key can be trusted. Consequently, a secure and efficient key-management scheme is crucial. Keys are also required for protection of application data. However, the focus here is on network-layer management information. Whereas keymanagement schemes for the upper layers can assume an already running network service, schemes for the protection of the network layer cannot. Keys are a prerequisite to bootstrap a protected network service. This article surveys the state of the art within key management for ad hoc networks, and analyzes their applicability for network-layer security. The analysis puts some emphasis on their applicability in scenarios such as emergency and rescue operations, as this work was initiated by a study of security in MANETs for emergency and rescue operations

Distribution of allele frequencies for genes associated with physical activity and/or physical capacity in a homogenous Norwegian cohort- a cross-sectional study

Background There are large individual differences in physical activity (PA) behavior as well as trainability of physical capacity. Heritability studies have shown that genes may have as much impact on exercise participation behavior as environmental factors. Genes that favor both trainability and participation may increase the levels of PA. The present study aimed to assess the allele frequencies in genes associated with PA and/or physical capacity, and to see if there is any association between these polymorphisms and self-reported PA levels in a cohort of middle-aged Norwegians of Scandinavian descent (n = 831; mean age mean age (± SD) 55.5 ± 3.8 years). Results The genotype distributions of the ACTN3 R577X, ACE I/D and MAOA uVNTR polymorphisms were similar to other populations of European descent. When comparing the genotype distribution between the low/medium level PA group (LMPA) and high level PA groups (HPA), a significant difference in ACTN3 577X allele distribution was found. The X allele frequency was 10% lower in the HPA level group (P = 0.006). There were no differences in the genotype distribution of the ACE I/D or MAOA uVNTR polymorphism. Education and previous participation in sports or outdoor activities was positively associated with the self-reported PA levels (P ≤ 0.001). Conclusions To the best of our knowledge, this is the first study to report association between ACTN3 R577X genotype and PA level in middle-aged Scandinavians. Nevertheless, the contribution of a single polymorphism to a complex trait, like PA level, is likely small. Socioeconomic variables, as education and previous participation in sports or outdoor activities, are positively associated with the self-reported PA levels