Efficacy of dynamic enhancement effects on Gd-EOB-DTPA-enhanced MRI for estimation of liver function assessed by 13C- Methacetin breath test.

Purpose: Contrast enhanced magnetic resonance imaging (MRI) is able to assess liver function by characteristic changes of signal intensity (SI).The aim was to evaluate dynamic contrast-enhanced SI-indices of the abdominal aorta, portal vein and liver.

Methods: 72 patients underwent Gd-EOB-DTPA-enhanced MRI and a 13C-methacetin-based liver breath test (13C-MBT) for evaluation of liver function.

Cellular production of a counterfeit viral protein confers immunity to infection by a related virus.

DNA copies of many non-retroviral RNA virus genes or portions thereof (NIRVs) are present in the nuclear genomes of many eukaryotes. These have often been preserved for millions of years of evolution, suggesting that they play an important cellular function. One possible function is resistance to infection by related viruses.

Disparity, diversity, and duplications in the Caryophyllales.

The role played by whole genome duplication (WGD) in plant evolution is actively debated. WGDs have been associated with advantages such as superior colonization, various adaptations, and increased effective population size. However, the lack of a comprehensive mapping of WGDs within a major plant clade has led to uncertainty regarding the potential association of WGDs and higher diversification rates.

Comparison of computed tomography (CT) and contrast-enhanced ultrasound (CEUS) for the quantitative evaluation of an ablation defect following radiofrequency ablation of malignant liver lesions.

Objective: To compare contrast-enhanced computed tomography (CT) and contrast-enhanced ultrasound (CEUS) for the quantitative evaluation of an ablation defect following radiofrequency ablation of malignant liver lesions in a prospective study.

Materials And Methods: 22 radiofrequency ablations of malignant liver tumors were performed. The ablation defects were then measured and evaluated by two independent examiners via contrast-enhanced computed tomography (CT) and contrast-enhanced ultrasound (CEUS) using a 1-5 MHz multifrequency convex ultrasound transducer (LOGIQ E9, GE) with respect to the short-axis diameter, the long-axis diameter, and the area.

Phage-mediated horizontal gene transfer of both prophage and heterologous DNA by ϕBB-1, a bacteriophage of Borrelia burgdorferi.

Horizontal gene transfer (HGT) in Borrelia burgdorferi, the Lyme disease agent, is likely mediated by bacteriophage. Studies of the B. burgdorferi phage, ϕBB-1 and its role in HGT have been hindered by the lack of an assay for readily characterizing phage-mediated DNA movement (transduction).

Widespread mitovirus sequences in plant genomes.

The exploration of the evolution of RNA viruses has been aided recently by the discovery of copies of fragments or complete genomes of non-retroviral RNA viruses (Non-retroviral Endogenous RNA Viral Elements, or NERVEs) in many eukaryotic nuclear genomes. Among the most prominent NERVEs are partial copies of the RNA dependent RNA polymerase (RdRP) of the mitoviruses in plant mitochondrial genomes. Mitoviruses are in the family Narnaviridae, which are the simplest viruses, encoding only a single protein (the RdRP) in their unencapsidated viral plus strand.

Evidence that ebolaviruses and cuevaviruses have been diverging from marburgviruses since the Miocene.

An understanding of the timescale of evolution is critical for comparative virology but remains elusive for many RNA viruses. Age estimates based on mutation rates can severely underestimate divergences for ancient viral genes that are evolving under strong purifying selection. Paleoviral dating, however, can provide minimum age estimates for ancient divergence, but few orthologous paleoviruses are known within clades of extant viruses.

Discovery and evolution of bunyavirids in arctic phantom midges and ancient bunyavirid-like sequences in insect genomes.

Unlabelled: Bunyaviridae is a large family of RNA viruses chiefly comprised of vertebrate and plant pathogens. We discovered novel bunyavirids that are approximately equally divergent from each of the five known genera. We characterized novel genome sequences for two bunyavirids, namely, Kigluaik phantom virus (KIGV), from tundra-native phantom midges (Chaoborus), and Nome phantom virus (NOMV), from tundra-invading phantom midges, and demonstrated that these bunyavirid-like sequences belong to an infectious virus by passaging KIGV in mosquito cell culture, although the infection does not seem to be well sustained beyond a few passages.

Selectively maintained paleoviruses in Holarctic water fleas reveal an ancient origin for phleboviruses.

The ecological model, Daphnia pulex (Cladocera: Daphniidae), is broadly distributed in Holarctic freshwater habitats and has been the subject of multidisciplinary study for over half a century, but never has a natural RNA virus infection been reported in daphnids. Here we report on a group of paleoviruses related to RNA dependent RNA polymerase in the genome of D. pulex.

Virus-host co-evolution under a modified nuclear genetic code.

Among eukaryotes with modified nuclear genetic codes, viruses are unknown. However, here we provide evidence of an RNA virus that infects a fungal host (Scheffersomyces segobiensis) with a derived nuclear genetic code where CUG codes for serine. The genomic architecture and phylogeny are consistent with infection by a double-stranded RNA virus of the genus Totivirus.

Phylogeny, integration and expression of sigma virus-like genes in Drosophila.

The recent and surprising discovery of widespread NIRVs (non-retroviral integrated RNA viruses) has highlighted the importance of genomic interactions between non-retroviral RNA viruses and their eukaryotic hosts. Among the viruses with integrated representatives are the rhabdoviruses, a family of negative sense single-stranded RNA viruses. We identify sigma virus-like NIRVs of Drosophila spp.

Evolutionary maintenance of filovirus-like genes in bat genomes.

Background: Little is known of the biological significance and evolutionary maintenance of integrated non-retroviral RNA virus genes in eukaryotic host genomes. Here, we isolated novel filovirus-like genes from bat genomes and tested for evolutionary maintenance. We also estimated the age of filovirus VP35-like gene integrations and tested the phylogenetic hypotheses that there is a eutherian mammal clade and a marsupial/ebolavirus/Marburgvirus dichotomy for filoviruses.

Filoviruses are ancient and integrated into mammalian genomes.

Background: Hemorrhagic diseases from Ebolavirus and Marburgvirus (Filoviridae) infections can be dangerous to humans because of high fatality rates and a lack of effective treatments or vaccine. Although there is evidence that wild mammals are infected by filoviruses, the biology of host-filovirus systems is notoriously poorly understood. Specifically, identifying potential reservoir species with the expected long-term coevolutionary history of filovirus infections has been intractable.

The evolution of novel fungal genes from non-retroviral RNA viruses.

Background: Endogenous derivatives of non-retroviral RNA viruses are thought to be absent or rare in eukaryotic genomes because integration of RNA viruses in host genomes is impossible without reverse transcription. However, such derivatives have been proposed for animals, plants and fungi, often based on surrogate bioinformatic evidence. At present, there is little known of the evolution and function of integrated non-retroviral RNA virus genes.

Rational proteomics I. Fingerprint identification and cofactor specificity in the short-chain oxidoreductase (SCOR) enzyme family.

The short-chain oxidoreductase (SCOR) family of enzymes includes over 2000 members identified in sequenced genomes. Of these enzymes, approximately 200 have been characterized functionally, and the three-dimensional crystal structures of approximately 40 have been reported. Since some SCOR enzymes are involved in hypertension, diabetes, breast cancer, and polycystic kidney disease, it is important to characterize the other members of the family for which the biological functions are currently unknown.

A structural and primary sequence comparison of the viral RNA-dependent RNA polymerases.

A systematic bioinformatic approach to identifying the evolutionarily conserved regions of proteins has verified the universality of a newly described conserved motif in RNA-dependent RNA polymerases (motif F). In combination with structural comparisons, this approach has defined two regions that may be involved in unwinding double-stranded RNA (dsRNA) for transcription. One of these is the N-terminal portion of motif F and the second is a large insertion in motif F present in the RNA-dependent RNA polymerases of some dsRNA viruses.

KP4 fungal toxin inhibits growth in Ustilago maydis by blocking calcium uptake.

KP4 is a virally encoded fungal toxin secreted by the P4 killer strain of Ustilago maydis. From our previous structural studies, it seemed unlikely that KP4 acts by forming channels in the target cell membrane. Instead, KP4 was proposed to act by blocking fungal calcium channels, as KP4 was shown to inhibit voltage-gated calcium channels in rat neuronal cells, and its effects on fungal cells were abrogated by exogenously added calcium.

Isolation of rat dihydrofolate reductase gene and characterization of recombinant enzyme.

While assays of many antifolate inhibitors for dihydrofolate reductase (DHFR) have been performed using rat DHFR as a target, neither the sequence nor the structure of rat DHFR is known. Here, we report the isolation of the rat DHFR gene through screening of a rat liver cDNA library. The rat liver DHFR gene has an open reading frame of 561 bp encoding a protein of 187 amino acids.

The H1 double-stranded RNA genome of Ustilago maydis virus-H1 encodes a polyprotein that contains structural motifs for capsid polypeptide, papain-like protease, and RNA-dependent RNA polymerase.

The Ustilago maydis viral (UmV) genome consists of three distinct size groups of double-stranded RNA (dsRNA) segments: H (heavy), M (medium), and L (light). The H segments have been suggested to encode all essential viral proteins, but without any molecular evidences. As a preliminary step to understand viral genomic organization and the molecular mechanism governing gene expression in UmV, we determined the complete nucleotide sequence of the H1 dsRNA genome in P1 viral killer subtype.

Simulation of the spherically symmetric stellar core collapse, bounce, and postbounce evolution of a star of 13 solar masses with boltzmann neutrino transport, and its implications for the supernova mechanism.

With exact three-flavor Boltzmann neutrino transport, we simulate the stellar core collapse, bounce, and postbounce evolution of a 13M star in spherical symmetry, the Newtonian limit, without invoking convection. In the absence of convection, prior spherically symmetric models, which implemented approximations to Boltzmann transport, failed to produce explosions. We consider exact transport to determine if these failures were due to the transport approximations made and to answer remaining fundamental questions in supernova theory.

Salivary histatin 5 and human neutrophil defensin 1 kill Candida albicans via shared pathways.

Salivary histatins are a family of basic histidine-rich proteins in which therapeutic potential as drugs against oral candidiasis is apparent, considering their potent in vitro antifungal activity and lack of toxicity to humans. Histatin 5 (Hst 5) kills the fungal pathogen Candida albicans via a mechanism that involves binding to specific sites on the yeast cell membrane and subsequent release of cellular ATP in the absence of cytolysis. We explored the killing pathway activated by Hst 5 and compared it to those activated by other antifungal agents.

Liposomes as formulation excipients for protein pharmaceuticals: a model protein study.

Purpose: The advent of recombinant DNA technology has made possible the pharmaceutical use of a wide range of proteins and peptides. However, the complex structure of proteins renders them susceptible to physical instabilities such as denaturation, aggregation and precipitation. We tested the hypothesis that partial unfolding and exposure of hydrophobic domains leads to physical instability, and investigated approaches to stabilize protein formulations.

Kinetics of ribosomal pausing during programmed -1 translational frameshifting.

In the Saccharomyces cerevisiae double-stranded RNA virus, programmed -1 ribosomal frameshifting is responsible for translation of the second open reading frame of the essential viral RNA. A typical slippery site and downstream pseudoknot are necessary for this frameshifting event, and previous work has demonstrated that ribosomes pause over the slippery site. The translational intermediate associated with a ribosome paused at this position is detected, and, using in vitro translation and quantitative heelprinting, the rates of synthesis, the ribosomal pause time, the proportion of ribosomes paused at the slippery site, and the fraction of paused ribosomes that frameshift are estimated.