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SummaryGrass carp reovirus (GCRV) is a member of the Aquareovirus genus of the family Reoviridae, a large family of dsRNA viruses infecting plants, insects, fishes and mammals. We report the first subnanometer-resolution three-dimensional (3D) structures of both GCRV core and virion by cryoelectron microscopy (cryoEM). These structures have allowed the delineation of interactions among the over 1000 molecules in this enormous macromolecular machine, and a detail comparison with other dsRNA viruses at the secondary structure level. The GCRV core structure shows that the inner proteins have strong structural similarities even at the level of secondary structure elements with those of orthoreoviruses, indicating that the structures involved in viral dsRNA interaction and transcription are highly conserved. In contrast, the level of similarity in structures decreases in the proteins situated in the outer layers of the virion. The proteins involved in host recognition and attachment exhibit the least similarities to other members of Reoviridae. Furthermore, in GCRV, the RNA-translocating turrets are in an open state and lack a counterpart for the σ1 protein situated on top of the close turrets observed in mammalian orthoreovirus (MRV). Interestingly, the distribution and organization of GCRV core proteins resembles those of the cytoplasmic polyhedrosis virus (CPV), a cypovirus and the structurally simplest member of the Reoviridae family. Our results suggest that GCRV occupies a unique structure niche between the simpler cypoviruses and the considerably more complex MRV, thus providing an important model for understanding the structural and functional conservation and diversity of this enormous family of dsRNA viruses.

We report the recording and reconstruction of x-ray diffraction patterns from single, unstained viruses, for the first time. By separating the diffraction pattern of the virus particles from that of their surroundings, we performed quantitative and high-contrast imaging of a single virion. The structure of the viral capsid inside a virion was visualized. This work opens the door for quantitative x-ray imaging of a broad range of specimens from protein machineries and viruses to cellular organelles. Moreover, our experiment is directly transferable to the use of x-ray free electron lasers, and represents an experimental milestone towards the x-ray imaging of large protein complexes.

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Background:Titanium has been the most popular material of choice for dental implantology over the past few decades. Its properties have been found to be most suitable for the success of implant treatment. But recently, zirconia is slowly emerging as one of the materials which might replace the gold standard of dental implant, i.e., titanium.Materials and Methods:Literature was searched to retrieve information about zirconia dental implant and studies were critically analyzed. PubMed database was searched for information about zirconia dental implant regarding mechanical properties, osseointegration, surface roughness, biocompatibility, and soft tissue health around it. The literature search was limited to English language articles published from 1975 to 2015.Results:A total of 45 papers met the inclusion criteria for this review, among the relevant search in the database.Conclusion:Literature search showed that some of the properties of zirconia seem to be suitable for making it an ideal dental implant, such as biocompatibility, osseointegration, favourable soft tissue response and aesthetics due to light transmission and its color. At the same time, some studies also point out its drawbacks. It was also found that most of the studies on zirconia dental implants are short-term studies and there is a need for more long-term clinical trials to prove that zirconia is worth enough to replace titanium as a biomaterial in dental implantology.

Human cytomegalovirus (HCMV) is the most genetically and structurally complex human herpesvirus and is composed of an envelope, a tegument, and a dsDNA-containing capsid. HCMV tegument plays essential roles in HCMV infection and assembly. Using cryo-electron tomography (cryoET), here we show that HCMV tegument compartment can be divided into two sub-compartments: an inner and an outer tegument. The inner tegument consists of densely-packed proteins surrounding the capsid. The outer tegument contains those components that are loosely packed in the space between the inner tegument and the pleomorphic glycoprotein-containing envelope. To systematically characterize the inner tegument proteins interacting with the capsid, we used chemical treatment to strip off the entire envelope and most tegument proteins to obtain a tegumented capsid with inner tegument proteins. SDS-polyacrylamide gel electrophoresis analyses show that only two tegument proteins, UL32-encoded pp150 and UL48-encoded high molecular weight protein (HMWP), remains unchanged in their abundance in the tegumented capsids as compared to their abundance in the intact particles. 3D reconstructions by single particle cryo-electron microscopy (cryoEM) reveal that the net-like layer of icosahedrally-ordered tegument densities are also the same in the tegumented capsid and in the intact particles. CryoET reconstruction of the tegumented capsid labeled with an anti-pp150 antibody is consistent with the biochemical and cryoEM data in localizing pp150 within the ordered tegument. Taken together, these results suggest that pp150, a betaherpesvirus-specific tegument protein, is a constituent of the net-like layer of icosahedrally-ordered capsid-bound tegument densities, a structure lacking similarities in alpha and gammaherpesviruses.

Grass carp reovirus (GCRV) is a relatively new virus first isolated in China and is a member of the Aquareovirus genus of the Reoviridae family. Recent report of genomic sequencing showed that GCRV shared high degree of homology with mammalian reovirus (MRV). As a step of our effort to understand the structural basis of GCRV pathogenesis, we determined the three-dimensional (3D) structure of GCRV capsid at 17 A resolution by electron cryomicroscopy. Each GCRV capsid has a multilayered organization, consisting of an RNA core, an inner, middle and outer protein layer. The outer layer is made up of 200 trimers that are arranged on an incomplete T=13 icosahedral lattice. A characteristic feature of this layer is the depression resulting from the absence of trimers around the peripentonal positions, revealing the underlying trimers on the middle layer. There are 120 subunits in the inner layer arranged with T=1 symmetry. These structural features are common to other members of the Reoviridae. Moreover, SDS-PAGE analysis showed that GCRV virions contain seven structural proteins (VP1-VP7). These structural proteins have a high degree of sequence homology to MRV, consistent with the structural similarities observed in our study. The high structural similarities of isolated GCRV and MRV suggest that future structural studies focusing on GCRV entering into and replicating within its host cell are necessary in order to fully understand the structural basis of GCRV pathogenesis.

A dvancements in technology and broadband have revolutionized the current practice of medicine. The field of pediatric cardiology is no exception given the need for prompt diagnosis and reliance on cardiac imaging to identify infants and children with potentially life-threatening cardiovascular disease. As the relationship between telemedicine and pediatric cardiology has advanced, it has created a need to develop a broad, comprehensive document reviewing all the various aspects of telemedicine in pediatric cardiology. For more than a decade, a significant body of literature has been published describing individual experiences and practices, yet there remains no comprehensive statement or document summarizing this rapidly advancing field. In an effort to describe the collective experience and to provide structure and guidance for pediatric cardiology practitioners and healthcare providers, we have developed a scientific statement on the use of telemedicine in pediatric cardiology.Specific areas explored in this document include both neonatal and fetal teleechocardiography, implications for training community sonographers, pulse oximetry programs, qualitative improvement and appropriate use criteria initiatives, and remote electrophysiological monitoring. This document also includes teleconsultation and teleausculation, direct-to-consumer and home monitoring programs, and a look into the use of telemedicine and pediatric cardiology in the intensive care setting. Furthermore, a detailed review of the legislative, public policy, and legal aspects of telemedicine is provided, along with financial and reimbursement information.Several terms are used in the literature interchangeably; a brief explanation is provided to help readers of this document. The term telehealth is defined as the use of technology to bridge distances in any aspect of medicine; telemedicine is the specific application of technology to conduct clinical medicine at a distance. The term telecardiology is defined as the broad application of telemedicine in the field of cardiology specifically, and tele-echocardiography is the most common application used within this field. ECHOCARDIOGRAPHY AND TELEMEDICINEEchocardiography is the most commonly used noninvasive cardiovascular imaging modality and is considered to be both safe and cost-effective. Tele-echocardiography can be described as a process in which a provider or a technician obtains cardiovascular ultrasound images from a given patient and these images are subsequently transmitted to an offsite location where a cardiologist can provide further analysis and interpretation. Thus, tele-echocardiography enables expert interpretation and consultation in a rapid and potentially geographically disparate fashion, enabling prompt and accurate decision making involving triage, transport, and therapeutic priorities. Tele-echocardiography is now routinely used across the age and subspecialty spectrum in pediatric cardiology.