Multifrequency Nanomechanical Mass Spectrometer Prototype for Measuring Viral Particles Using Optomechanical Disk Resonators

Nanomechanical mass spectrometry allows characterization of analytes with broad mass range, from small proteins to bacterial cells, and with unprecedented mass sensitivity. In this work, we show a novel multifrequency nanomechanical mass spectrometer prototype designed for focusing, guiding and soft-landing of nanoparticles and viral particles...

VIRUSCAN: Identification and characterization of viruses from their nano-mechanical properties

Measuring the nano-mechanical properties of viruses opens a new route to identify viruses and to assess their infectiveness. Current targeted techniques, like PCR, are only suitable for confirmation and have a high false positive rate due to cross contamination and DNA strands presents in the blood sample after former infection. The...

Virus spread in networks

The influence of the network characteristics on the virus spread is analyzed in a new-the N-intertwined Markov chain-model, whose only approximation lies in the application of mean field theory. The mean field approximation is quantified in detail. The N-intertwined model has been compared with the exact 2N-state Markov model and with previously...

Suitability of PER.C6 cells to generate epidemic and pandemic influenza vaccine strains by reverse genetics

Reverse genetics, the generation of influenza viruses from cDNA, presents a rapid method for creating vaccine strains. The technique necessitates the use of cultured cells. Due to technical and regulatory requirements, the choice of cell lines for production of human influenza vaccines is limited. PER.C6® cells, among the most extensively...

Heterogeneous protection in regular and complete bi-partite networks

We examine the influence of heterogeneous curing rates for a SIS model, used for malware spreading on the Internet, information dissemination in unreliable networks, and propagation of failures in networks. The topology structures considered are the regular graph which represents the homogenous network structures and the complete bi-partite...

A new metric for robustness with respect to virus spread

The robustness of a network is depending on the type of attack we are considering. In this paper we focus on the spread of viruses on networks. It is common practice to use the epidemic threshold as a measure for robustness. Because the epidemic threshold is inversely proportional to the largest eigenvalue of the adjacency matrix, it seems easy...

The minimal spectral radius of graphs with a given diameter

The spectral radius of a graph (i.e., the largest eigenvalue of its corresponding adjacency matrix) plays an important role in modeling virus propagation in networks. In fact, the smaller the spectral radius, the larger the robustness of a network against the spread of viruses. Among all connected graphs on n nodes the path Pn has minimal...

Virus spread in complete bi-partite graphs

In this paper we study the spread of viruses on the complete bi-partite graph Km,n. Using mean field theory we first show that the epidemic threshold for this type of graph satifies Tc = 1/√MN, hence, confirming previous results from literature. Next, we find an expression for the average number of infected nodes in the steady state. In addition...

Robustness of networks against viruses: The role of the spectral radius

In this paper we study the spectral radius of a number of real-life networks. This study is motivated by the fact that the smaller the spectral radius, the higher the robustness of a network against the spread of viruses. First we study how wellknown upper bounds for the spectral radius of graphs match to the spectral radii of the social network...

Role of bacterial virulence proteins in Agrobacterium-mediated transformation of Aspergillus awamori

The Agrobacterium-mediated transformation of Aspergillus awamori was optimized using defined co-cultivation conditions, which resulted in a reproducible and efficient transformation system. Optimal co-cultivation conditions were used to study the role of Agrobacterium tumefaciens virulence proteins in T-DNA transfer. This study revealed that...

Accumulation of mitochondrial DNA mutations in human immunodeficiency virus-infected patients treated with nucleoside-analogue reverse-transcriptase inhibitors

Nucleoside reverse-transcriptase inhibitor (NRTI) therapy for human immunodeficiency virus (HIV) infection has been associated with mitochondrial DNA (mtDNA) polymerase-γ inhibition and subsequent mtDNA depletion. Effects on mtDNA mutation, although suggested by critical involvement of polymerase-γ in DNA-repair reactions, are unknown. In the...

Membrane-type matrix metalloproteinase-mediated angiogenesis in a fibrin-collagen matrix

Adult angiogenesis, associated with pathologic conditions, is often accompanied by the formation of a fibrinous exudate. This temporary matrix consists mainly of fibrin but is intermingled with plasma proteins and collagen fibers. The formation of capillary structures in a fibrinous matrix in vivo was mimicked by an in vitro model, in which...

Recombinant adenoviral vectors have adjuvant activity and stimulate T cell responses against tumor cells

The host-immune response against adenoviruses forms a major obstacle for their use as gene therapy vectors for treatment of genetic defects. None the less, they are the preferred vectors for in vivo gene transfer in experimental gene therapy protocols for cancer. In this article we demonstrate the antitumor efficacy of adenovirus-mediated...

Peptide mimics of a conformationally constrained protective epitopes of respiratory syncytial virus fusion protein

Aims: To identify peptides that mimic (mimotopes) conformational and protective epitopes of RSV fusion protein and to assess their efficacy as immunogens and potential vaccines. Material and methods: An 8-mer solid- phase (TG resin) library was screened with a neutralising and protective RSV fusion protein specific monoclonal antibodies (Mab-19)...

The potential of Lactobacillus as a carrier for oral immunization: Development and preliminary characterization of vector systems for targeted delivery of antigens

Oral administration of lactobacilli evokes mucosal and systemic immune responses against epitopes associated with these organisms (Gerritse et al., 1990, 1991). The adjuvant function of different Lactobacillus species was investigated under the conditions of intraperitoneal (i.p.) injection or oral administration. After i.p. injection of...

Mechanisms of inactivation of bacteriophage phiX174 and its DNA in aerosols by ozone and ozonized cyclohexene

The mechanisms of inactivation of aerosolized bacteriophage phiX174 in atmospheres containing ozone, cyclohexene, or ozonized cyclohexene were studied by using 32P-labelled phage. The inactivation of the aerosolized phage in clean air or in air containing cyclohexene is due to damage of the protein coat since the deoxyribonucleic acid (DNA)...

Survival of aerosolized bacteriophage phiX174 in air containing ozone olefin mixtures

The effects of ozone and ozonized olefins on aerosol survival of bacteriophage phiX174 were studied. The ozone concentrations used were between 0 and 110 parts/109, giving decay rates up to 0.03 min-1. The olefins used were trans 2 butene and cyclohexene in concentrations of 500 parts/109 and 2.4 parts/106, respectively. Olefins alone have no...

Radiosensitization of biologically active DNA in cellular extracts by oxygen. Evidence that the presence of SH compounds is not required

The radiosensitization by oxygen of biologically active bacteriophage DNA in bacterial extracts was studied. The oxygen effect in such a system appeared not to be due or only to a minor extent to the presence of endogenous sulphydryl compounds. The components in a cell extract which enable oxygen and other sensitizers to sensitize DNA could not...