Search results for "Sack"

Slow Infection due to Lowering the Amount of Intact versus Empty Particles Is a Characteristic Feature of Coxsackievirus B5 Dictated by the Structura…

2019

Enterovirus B species typically cause a rapid cytolytic infection leading to efficient release of progeny viruses. However, they are also capable of persistent infections in tissues, which are suggested to contribute to severe chronic states such as myocardial inflammation and type 1 diabetes. In order to understand the factors contributing to differential infection strategies, we constructed a chimera by combining the capsid proteins from fast-cytolysis-causing echovirus 1 (EV1) with nonstructural proteins from coxsackievirus B5 (CVB5), which shows persistent infection in RD cells. The results showed that the chimera behaved similarly to parental EV1, leading to efficient cytolysis in both…

Coxsackievirus A9 Infects Cells via Nonacidic Multivesicular Bodies

2014

ABSTRACT Coxsackievirus A9 (CVA9) is a member of the human enterovirus B species in the Enterovirus genus of the family Picornaviridae . According to earlier studies, CVA9 binds to αVβ3 and αVβ6 integrins on the cell surface and utilizes β2-microglobulin, dynamin, and Arf6 for internalization. However, the structures utilized by the virus for internalization and uncoating are less well understood. We show here, based on electron microscopy, that CVA9 is found in multivesicular structures 2 h postinfection (p.i.). A neutral red labeling assay revealed that uncoating occurs mainly around 2 h p.i., while double-stranded RNA is found in the cytoplasm after 3 h p.i. The biogenesis of multivesicu…

Hydrophobic pocket targeting probes for enteroviruses

2015

Visualization and tracking of viruses without compromising their functionality is crucial in order to understand virus targeting to cells and tissues, and to understand the subsequent subcellular steps leading to virus uncoating and replication. Enteroviruses are important human pathogens causing a vast number of acute infections, and are also suggested to contribute to the development of chronic diseases like type I diabetes. Here, we demonstrate a novel method to target site-specifically the hydrophobic pocket of enteroviruses. A probe, a derivative of Pleconaril, was developed and conjugated to various labels that enabled the visualization of enteroviruses under light and electron micros…

Early entry events in Echovirus 30 infection

2020

Echovirus 30 (E30), a member of the enterovirus B species, is a major cause of viral meningitis, targeting children and adults alike. While it is a frequently isolated enterovirus and the cause of several outbreaks all over the world, surprisingly little is known regarding its entry and replication strategy within cells. In this study, we used E30 strain Bastianni (E30B) generated from an infectious cDNA clone in order to study early entry events during infection in human RD cells. E30B required the newly discovered Fc echovirus receptor (FcRn) for successful infection, but not the coxsackievirus and adenovirus receptor (CAR) or decay-accelerating factor (DAF), although an interaction with …

2019

Abstract Type B Coxsackieviruses (CVBs) belong to the enterovirus genus, and they cause both acute and chronic diseases in humans. CVB infections usually lead to flu-like symptoms but can also result in more serious diseases such as myocarditis, aseptic meningitis and life-threatening multi-organ infections in young infants. Thus, CVBs have long been considered as important targets of future vaccines. We have previously observed CVB1 capsid disintegration and virus concentration decrease with 12-day long formalin inactivation protocol. Here a scalable ion exchange chromatography purification method was developed, and purified CVB1 was inactivated with UV-C or formalin. Virus morphology and …

Optimal selection of touristic packages based on user preferences during sports mega-events

2022

Sport mega-events, such as the Soccer World Cup or Olympic Games, attract many visitors from all over the world. Most of these visitors are also interested in, besides attending the sports events, visiting the host nation and the neighboring countries. In this paper, we focus on the upcoming FIFA World Cup Qatar 2022. As per the schedule of the tournament, a national team can play 7 matches at most. Therefore, a supporter will have six short breaks (of three to five days) between consecutive matches in addition to two longer ones, immediately before and after the tournament, during which they can plan some touris- tic trips. We study the problem faced by a touristic trip provider who wants …

Solving Stochastic Nonlinear Resource Allocation Problems Using a Hierarchy of Twofold Resource Allocation Automata

2010

In a multitude of real-world situations, resources must be allocated based on incomplete and noisy information. However, in many cases, incomplete and noisy information render traditional resource allocation techniques ineffective. The decentralized Learning Automata Knapsack Game (LAKG) was recently proposed for solving one such class of problems, namely the class of Stochastic Nonlinear Fractional Knapsack Problems. Empirically, the LAKG was shown to yield a superior performance when compared to methods which are based on traditional parameter estimation schemes. This paper presents a completely new online Learning Automata (LA) system, namely the Hierarchy of Twofold Resource Allocation …

GRASP with path relinking for the orienteering problem

2014

In this paper, we address an optimization problem resulting from the combination of the well-known travelling salesman and knapsack problems. In particular, we target the orienteering problem, originated in the context of sport, which consists of maximizing the total score associated with the vertices visited in a path within the available time. The problem, also known as the selective travelling salesman problem, is NP-hard and can be formulated as an integer linear program. Since the 1980s, several solution methods for this problem have been developed and applied to a variety of fields, particularly in routing and tourism. We propose a heuristic method—based on the Greedy Randomized Adapt…

A genetic algorithm for the minimum generating set problem

2016

Graphical abstractDisplay Omitted HighlightsWe propose a novel formulation for the MGS problem based on multiple knapsack.The so-conceived MGS problem is solved by a novel GA.The GA embeds an intelligent construction method and specialized crossover operators.We perform a thorough comparison with regards to state-of-the-art algorithms.The proposal proves to be very competitive, specially for large and hard instances. Given a set of positive integers S, the minimum generating set problem consists in finding a set of positive integers T with a minimum cardinality such that every element of S can be expressed as the sum of a subset of elements in T. It constitutes a natural problem in combinat…

The Multiple Multidimensional Knapsack with Family-Split Penalties

2021

Abstract The Multiple Multidimensional Knapsack Problem with Family-Split Penalties (MMdKFSP) is introduced as a new variant of both the more classical Multi-Knapsack and Multidimensional Knapsack Problems. It reckons with items categorized into families and where if an individual item is selected to maximize the profit, all the items of the same family must be selected as well. Items belonging to the same family can be assigned to different knapsacks; however, in this case, split penalties are incurred. This problem arises in resource management of distributed computing contexts and Service Oriented Architecture environments. An exact algorithm based on the exploitation of a specific combi…