Nuclear export restricts Gdown1 to a mitotic function.

Approximately half of purified mammalian RNA polymerase II (Pol II) is associated with a tightly interacting sub-stoichiometric subunit, Gdown1. Previous studies have established that Gdown1 inhibits transcription initiation through competitive interactions with general transcription factors and blocks the Pol II termination activity of transcription termination factor 2 (TTF2). However, the biological functions of Gdown1 remain poorly understood. Here, we utilized genetic, microscopic, and multi-omics approaches to functionally characterize Gdown1 in three human cell lines. Acute depletion of Gdown1 caused minimal direct effects on transcription. We show that Gdown1 resides predominantly in the cytoplasm of interphase cells, shuttles between the cytoplasm and nucleus, and is regulated by nuclear export. Gdown1 enters the nucleus at the onset of mitosis. Consistently, genetic ablation of Gdown1 is associated with partial de-repression of mitotic transcription, and Gdown1 KO cells present with evidence of aberrant mitoses coupled to p53 pathway activation. Evidence is presented demonstrating that Gdown1 modulates the combined functions of purified productive elongation factors PAF1C, RTF1, SPT6, DSIF and P-TEFb in vitro. Collectively, our findings support a model wherein the Pol II-regulatory function of Gdown1 occurs during mitosis and is required for genome integrity.

Improved in vitro wound healing in response to a superoxidised solution.

OBJECTIVE: This study assessed wound healing in response to a superoxidised solution using an in vitro wound healing model. METHOD: Prewounded reconstructed full-thickness human skin models were treated with 10µl of either superoxidised solution (Hydrocyn aqua, Bactiguard South East Asia Sdn. Bhd., Malaysia) or Dulbecco's phosphate buffered saline (DPBS) and incubated at 37°C for up to seven days, with additional treatments added every 48 hours. On days 0, 1, 2, 5 and 7, triplicate samples were taken for specific immunostaining against cytokeratin 14 and vimentin. At each timepoint, horizontal and vertical wound diameters were measured to demonstrate wound closure. Maintenance media was taken at the same timepoints for the measurement of secreted proinflammatory cytokines interleukin (IL)-1ß, IL-6 and tumour necrosis factor (TNF)-ɑ. RESULTS: At day 1, the superoxidised solution induced significantly lower diameter measurements compared with baseline data at day 0. Both treatment groups demonstrated significantly lower diameter measurements by day 2 when compared with the baseline; however, the average wound size of samples treated with the superoxidised solution was significantly lower when compared to the DPBS-treated group (p<0.05). No significant difference in expression of any proinflammatory was identified at any timepoint. CONCLUSION: Application of the superoxidised solution resulted in significantly improved wound closure over the first 48 hours in comparison to DPBS-treatment. Furthermore, application of the superoxidised solution did not induce significant proinflammatory effects, despite the significantly reduced wound diameter.

Cytomegalovirus late transcription factor target sequence diversity orchestrates viral early to late transcription.

Beta- and gammaherpesviruses late transcription factors (LTFs) target viral promoters containing a TATT sequence to drive transcription after viral DNA replication has begun. Human cytomegalovirus (HCMV), a betaherpesvirus, uses the UL87 LTF to bind both TATT and host RNA polymerase II (Pol II), whereas the UL79 LTF has been suggested to drive productive elongation. Here we apply integrated functional genomics (dTag system, PRO-Seq, ChIP-Seq, and promoter function assays) to uncover the contribution of diversity in LTF target sequences in determining degree and scope to which LTFs drive viral transcription. We characterize the DNA sequence patterns in LTF-responsive and -unresponsive promoter populations, determine where and when Pol II initiates transcription, identify sites of LTF binding genome-wide, and quantify change in nascent transcripts from individual promoters in relation to core promoter sequences, LTF loss, stage of infection, and viral DNA replication. We find that HCMV UL79 and UL87 LTFs function concordantly to initiate transcription from over half of all active viral promoters in late infection, while not appreciably affecting host transcription. Both LTFs act on and bind to viral early-late and late kinetic-class promoters. Over one-third of these core promoters lack the TATT and instead have a TATAT, TGTT, or YRYT. The TATT and non-TATT motifs are part of a sequence block with a sequence code that correlates with promoter transcription level. LTF occupancy of a TATATA palindrome shared by back-to-back promoters is linked to bidirectional transcription. We conclude that diversity in LTF target sequences shapes the LTF-transformative program that drives the viral early-to-late transcription switch.

Human cytomegalovirus IE2 drives transcription initiation from a select subset of late infection viral promoters by host RNA polymerase II.

Herpesvirus late promoters activate gene expression after viral DNA synthesis has begun. Alphaherpesviruses utilize a viral immediate-early protein to do this, whereas beta- and gammaherpesviruses primarily use a 6-member set of viral late-acting transcription factors (LTF) that are drawn to a TATT sequence in the late promoter. The betaherpesvirus, human cytomegalovirus (HCMV), produces three immediate-early 2 protein isoforms, IE2-86, IE2-60, IE2-40, late in infection, but whether they activate late viral promoters is unknown. Here, we quickly degrade the IE2 proteins in late infection using dTag methodology and analyze effects on transcription using customized PRO-Seq and computational methods combined with multiple validation methods. We discover that the IE2 proteins selectively drive RNA Pol II transcription initiation at a subset of viral early-late and late promoters common to different HCMV strains, but do not substantially affect Pol II transcription of the 9,942 expressed host genes. Most of the IE2-activated viral late infection promoters lack the TATT sequence bound by the HCMV UL87-encoded LTF. The HCMV TATT-binding protein is not mechanistically involved in late RNA expression from the IE2-activated TATT-less UL83 (pp65) promoter, as it is for the TATT-containing UL82 (pp71) promoter. While antecedent viral DNA synthesis is necessary for transcription from the late infection viral promoters, continued viral DNA synthesis is unnecessary. We conclude that in late infection the IE2 proteins target a distinct subset of HCMV early-late and late promoters for transcription initiation by RNA Pol II. Commencement of viral DNA replication renders the HCMV genome late promoters susceptible to late-acting viral transcription factors.

Avian metapneumovirus subtype B vaccination in commercial broiler chicks: heterologous protection and selected host transcription responses to subtype A or B challenge.

Avian metapneumovirus (aMPV) causes respiratory disease and drops in egg production in chickens, and is routinely controlled by vaccination. However, the host's immune response to virulent challenge in vaccinated or unvaccinated broiler chickens is poorly characterized. We show that subtype B vaccination offers heterologous (subtype A challenge) and homologous (subtype B challenge) protection. Subtype B challenge caused significantly greater humoral antibody titres in vaccinated and unvaccinated chickens. In turbinate and lung tissues of unvaccinated-challenged chickens, IgA and IgY mRNA transcription was significantly up-regulated after subtype B challenge compared to subtype A. Cellular immunity (CD8-α and CD8-ß) gene transcripts were significantly up-regulated during early and later stages of infection from subtype B or subtype A, respectively. Immune gene transcriptional responses (IL-1ß, IL-6 and IL-18) were significantly up-regulated after challenge. Gene transcription results showed that mRNA expression levels of CD8-α, CD8-ß, TLR3 and IL-6, particularly in turbinate and trachea tissues, are useful parameters to include in future aMPV vaccination-challenge studies.

Post mortem computed tomography is highly sensitive for pyelonephritis. A radiologic-pathologic correlation series.

Pyelonephritis is a potentially lethal disease occasionally encountered in the forensic setting. Post mortem computed tomography (PMCT) is an important investigative tool for the forensic pathologist. In particular, it may be used to document and screen disease prior to traditional autopsy methods. While the sensitivity and specificity of computed tomography for pyelonephritis is well studied in the antemortem clinical setting, the test characteristics of PMCT are not yet described in the forensic pathology literature. A series of all cases of fatal pyelonephritis identified at the Ontario Forensic Pathology Service, over the course of 1 year was studied. Radiologic, clinical and pathologic findings were reviewed. A fulsome autopsy, including histopathologic examination, was considered the gold standard for sensitivity and specificity calculations. A control group consisting of 16 cases without pyelonephritis (ex: opiate toxicity) in which both PMCT and histologic data were available by way of comparison. Sixteen cases of pyelonephritis were identified. Post mortem computed tomographical signs of pyelonephritis included asymmetric renal enlargement, perinephric fat stranding, and ectopic renal air. The most (57%) individually sensitive of these findings was perinephric fat stranding but sensitivity increased to 100% if any of the three signs were present. The control group analysis revealed the specificity of air asymmetry (81%), asymmetric renal enlargement (81%), and fat stranding (69%). PMCT findings may rule in a diagnosis of pyelonephritis, and should prompt the pathologist to grossly and microscopically examine the kidneys.

COVID-19 Outbreaks in Correctional Facilities with Work-Release Programs - Idaho, July-November 2020.

As of April 16, 2021, U.S. correctional and detention facilities reported 399,631 cases of COVID-19 in incarcerated persons, resulting in 2,574 deaths (1). During July 14-November 30, 2020, COVID-19 was diagnosed in 382 persons incarcerated in Idaho correctional facilities with work-release programs. Work-release programs (which place incarcerated persons in community businesses) have social and economic benefits, but might put participants at increased risk for bidirectional transmission of SARS-CoV-2, the virus that causes COVID-19. The Idaho Department of Correction (IDOC) operates 13 state-run correctional facilities, including six low-security facilities dedicated to work-release programs. This report describes COVID-19 outbreaks in five IDOC facilities with work-release programs,* provides the mitigation strategies that IDOC implemented, and describes the collaborative public health response. As of November 30, 2020, 382 outbreak-related COVID-19 cases were identified among incarcerated persons in five Idaho correctional facilities with work-release programs; two outbreaks were linked to food processing plants. Mitigation strategies that helped to control outbreaks in IDOC facilities with work-release programs included isolation of persons with COVID-19, identification and quarantine of close contacts, mass testing of incarcerated persons and staff members, and temporary suspension of work-release programs. Implementation of public health recommendations for correctional and detention facilities with work-release programs, including mass testing and identification of high-risk work sites, can help mitigate SARS-CoV-2 outbreaks. Incarcerated persons participating in work-release should be included in COVID-19 vaccination plans.

Route of infectious bronchitis virus vaccination determines the type and magnitude of immune responses in table egg laying hens.

Chicken immune responses to infectious bronchitis virus (IBV) vaccination can depend on route of administration, vaccine strain and bird age. Typically for layer chickens, IBV vaccinations are administered by spray in the hatchery at day-old and boosted at intervals with live vaccines via drinking water (DW). Knowledge of live attenuated IBV vaccine virus kinetics and the immune response in egg-laying hens is exceptionally limited. Here, we demonstrated dissemination of vaccine viruses and differences in hen innate, mucosal, cellular and humoral immune responses following vaccination with Massachusetts or 793B strains, administered by DW or oculonasal (ON) routes. Detection of IBV in the Mass-vaccinated groups was greater during early time-points, however, 793B was detected more frequently at later timepoints. Viral RNA loads in the Harderian gland and turbinate tissues were significantly higher for ON-Mass compared to all other vaccinated groups. Lachrymal fluid IgY levels were significantly greater than the control at 14 days post-vaccination (dpv) for both vaccine serotypes, and IgA mRNA levels were significantly greater in ON-vaccinated groups compared to DW-vaccinated groups, demonstrating robust mucosal immune responses. Cell mediated immune gene transcripts (CD8-α and CD8-ß) were up-regulated in turbinate and trachea tissues. For both vaccines, dissemination and vaccine virus clearance was slower when given by DW compared to the ON route. For ON administration, both vaccines induced comparable levels of mucosal immunity. The Mass vaccine induced cellular immunity to similar levels regardless of vaccination method. When given either by ON or DW, 793B vaccination induced significantly higher levels of humoral immunity.

Tattoo visualization using cross-polarized lighting and infrared photography.

Identification of the deceased is a critical responsibility of the death investigation system. If visual identification is inconclusive, tattoos can provide secondary identification but may be difficult to visualize at various stages of decomposition. We describe the case of a 35-year-old male found submerged underwater by police after swimming at a pier. The decedent was last seen earlier that day. Signs of immersion including sodden hands, feet, and clothing, wet sand on the torso and legs, and heavy edematous legs were observed. The post-mortem blood alcohol concentration was 427 mg/100 mL; signs of recent traumatic injury were not present. The immediate cause of death was drowning as a consequence of ethanol intoxication. When pulled from the water, the decedent's shoulder tattoo was not visible. Cross-polarized lighting and infrared photography visualized the tattoo to help confirm identity. These photographic methods were compared to hydrogen peroxide and optical coherence tomography techniques and described in detail to assist with future cases.

Cascading Crises: Society in the Age of COVID-19.

The tsunami of change triggered by the COVID-19 pandemic has transformed society in a series of cascading crises. Unlike disasters that are more temporarily and spatially bounded, the pandemic has continued to expand across time and space for over a year, leaving an unusually broad range of second-order and third-order harms in its wake. Globally, the unusual conditions of the pandemic-unlike other crises-have impacted almost every facet of our lives. The pandemic has deepened existing inequalities and created new vulnerabilities related to social isolation, incarceration, involuntary exclusion from the labor market, diminished economic opportunity, life-and-death risk in the workplace, and a host of emergent digital, emotional, and economic divides. In tandem, many less advantaged individuals and groups have suffered disproportionate hardship related to the pandemic in the form of fear and anxiety, exposure to misinformation, and the effects of the politicization of the crisis. Many of these phenomena will have a long tail that we are only beginning to understand. Nonetheless, the research also offers evidence of resilience on several fronts including nimble organizational response, emergent communication practices, spontaneous solidarity, and the power of hope. While we do not know what the post COVID-19 world will look like, the scholarship here tells us that the virus has not exhausted society's adaptive potential.

Influences of swab types and storage temperatures on isolation and molecular detection of Mycoplasma gallisepticum and Mycoplasma synoviae.

Routine diagnosis of Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) is performed by collecting oropharyngeal swabs, followed by isolation and/or detection by molecular methods. The storage temperature, storage duration and the type of swab could be critical factors for successful isolation or molecular detection. The aim of this study was to compare the influence of different types of cotton-tipped swab stored at different temperatures, on the detection of MG and MS. To achieve this, combined use of traditional culture analysis (both agar and broth), with modern molecular detection methods was utilized. Performances of wooden and plastic shaft swabs, both without transport medium, were compared. Successful culture of M. gallisepticum was significantly more efficient from plastic swabs when compared to wooden, whereas no difference was seen for the re-isolation of M. synoviae. Storage at 4°C compared to room temperature also increased the efficiency of culture detection for both Mycoplasma species. When stored at room temperature, PCR detection limits of both MG and MS were significantly lower for wooden compared to plastic swabs. The qPCR data showed similar detection limits for both swab types when stored at both temperatures. The results suggest that swabs with a plastic shaft are preferred for MG and MS detection by both culture and PCR. While a lower storage temperature (4°C) is optimal for culture recovery, it seems that both temperatures investigated here are adequate for molecular detection and it is the swab type which carries a greater influence.

Use of the nuclear walk-on methodology to determine sites of RNA polymerase II initiation and pausing and quantify nascent RNAs in cells.

Transcription by RNA polymerase II (Pol II) is controlled during initiation, elongation, and termination by a large variety of transcription factors, the state of chromatin modifications, and environmental conditions. Herein we describe experimental approaches for the examination of Pol II transcription at semi-global and genome-wide scales through analysis of nascent Pol II transcripts. We begin with a description of the nuclear walk-on (NWO) assay, which involves rapid isolation of nuclei in the presence of EDTA, followed by extension of about a quarter of the nascent transcripts with 32P-CTP. Labeled nascent transcripts are then analyzed by denaturing PAGE and phosphorimaging followed by densitometry analysis to quantify the signal on the gel. A parallel reaction containing α-amanitin to inhibit Pol II reveals transcription due to Pol I and Pol III, which can be subtracted to yield a profile of Pol II transcription. We then describe how to use the NWO as a front end for PRO-Seq and PRO-Cap methods, which permit the genome-wide characterization of Pol II transcription at nucleotide resolution and provide precise information about sites of transcription initiation and pausing. We discuss strategies for optimizing sequencing methods that capture nascent Pol II transcripts, methods of bias reduction, and approaches for normalizing these and other sequencing datasets using spike-in controls.

In-Situ Screening of Soybean Quality with a Novel Handheld Near-Infrared Sensor.

This study evaluates a novel handheld sensor technology coupled with pattern recognition to provide real-time screening of several soybean traits for breeders and farmers, namely protein and fat quality. We developed predictive regression models that can quantify soybean quality traits based on near-infrared (NIR) spectra acquired by a handheld instrument. This system has been utilized to measure crude protein, essential amino acids (lysine, threonine, methionine, tryptophan, and cysteine) composition, total fat, the profile of major fatty acids, and moisture content in soybeans (n = 107), and soy products including soy isolates, soy concentrates, and soy supplement drink powders (n = 15). Reference quantification of crude protein content used the Dumas combustion method (AOAC 992.23), and individual amino acids were determined using traditional protein hydrolysis (AOAC 982.30). Fat and moisture content were determined by Soxhlet (AOAC 945.16) and Karl Fischer methods, respectively, and fatty acid composition via gas chromatography-fatty acid methyl esterification. Predictive models were built and validated using ground soybean and soy products. Robust partial least square regression (PLSR) models predicted all measured quality parameters with high integrity of fit (RPre ≥ 0.92), low root mean square error of prediction (0.02-3.07%), and high predictive performance (RPD range 2.4-8.8, RER range 7.5-29.2). Our study demonstrated that a handheld NIR sensor can supplant expensive laboratory testing that can take weeks to produce results and provide soybean breeders and growers with a rapid, accurate, and non-destructive tool that can be used in the field for real-time analysis of soybeans to facilitate faster decision-making.

Fatal secondary aortoduodenal fistula diagnosed with postmortem computed tomography angiography.

Secondary aortoduodenal fistula (AEF), although less rare than its primary form, is an uncommon and frequently lethal cause of gastrointestinal (GI) bleeding. We report a case of fatal GI hemorrhage in a woman with a remote history of endovascular graft repair of an abdominal aortic aneurysm. Postmortem examination included computed tomography (PMCT) and CT angiography (PMCTA), which revealed air in the aorta, loss of the fat plane between the aorta and duodenum, and direct extravasation of contrast from the aorta into the duodenum. To our knowledge, this is the first published report of secondary AEF diagnosed by PMCT and confirmed with PMCTA. We propose a set of imaging criteria by which PMCTA can be used to supplant traditional anatomical dissection in the medicolegal investigation of deaths due to AEF.

Impact of RNA structure on ZFP36L2 interaction with luteinizing hormone receptor mRNA.

ZFP36L2 (L2) destabilizes AU-rich element (ARE)-containing transcripts and has been implicated in female fertility. We have shown that only one of three putative AREs within the 3' UTR of murine luteinizing hormone receptor mRNA, ARE2197 (UAUUUAU), is capable of interacting with L2. To assess whether structural elements of ARE2197 could explain this unique binding ability, we performed whole-transcript SHAPE-MaP (selective 2' hydroxyl acylation by primer extension-mutational profiling) of the full-length mLHR mRNA. The data revealed that the functional ARE2197 is located in a hairpin loop structure and most nucleotides are highly reactive. In contrast, each of the nonbinding AREs, 2301 and 2444, contains only a pentamer AUUUA; and in ARE2301 much of the ARE sequence is poorly accessible. Because the functional mARE was also found to be conserved in humans at the sequence level (ARE 2223), we decided to investigate whether binding and structure are also preserved. Similar to mouse, only one ARE in hLHR mRNA is capable of binding to L2; and it is also located in a hairpin structure, based on our SHAPE-MaP data. To investigate the role of secondary structure in the binding, we mutated specific nucleotides in both functional AREs. Mutations in the flexible stem region proximal to the loop that enforce strong base-pairing, drastically reduced L2 binding affinity; this confirms that the structural context is critical for L2 recognition of hARE2223. Collectively, our results suggest that a combination of minimal ARE sequence, placement of the ARE in a hairpin loop, and stem flexibility mediate high-affinity L2 binding to hLHR mRNA.

Inducing circular RNA formation using the CRISPR endoribonuclease Csy4.

Circular RNAs (circRNAs) are highly stable, covalently closed RNAs that are regulated in a spatiotemporal manner and whose functions are largely unknown. These molecules have the potential to be incorporated into engineered systems with broad technological implications. Here we describe a switch for inducing back-splicing of an engineered circRNA that relies on the CRISPR endoribonuclease, Csy4, as an activator of circularization. The endoribonuclease activity and 3' end-stabilizing properties of Csy4 are particularly suited for this task. Coexpression of Csy4 and the circRNA switch allows for the removal of downstream competitive splice sites and stabilization of the 5' cleavage product. This subsequently results in back-splicing of the 5' cleavage product into a circRNA that can translate a reporter protein from an internal ribosomal entry site (IRES). Our platform outlines a straightforward approach toward regulating splicing and could find potential applications in synthetic biology as well as in studying the properties of different circRNAs.

Oxidative stress rapidly stabilizes promoter-proximal paused Pol II across the human genome.

Oxidative stress has pervasive effects on cells but how they respond transcriptionally upon the initial insult is incompletely understood. We developed a nuclear walk-on assay that semi-globally quantifies nascent transcripts in promoter-proximal paused RNA polymerase II (Pol II). Using this assay in conjunction with ChIP-Seq, in vitro transcription, and a chromatin retention assay, we show that within a minute, hydrogen peroxide causes accumulation of Pol II near promoters and enhancers that can best be explained by a rapid decrease in termination. Some of the accumulated polymerases slowly move or 'creep' downstream. This second effect is correlated with and probably results from loss of NELF association and function. Notably, both effects were independent of DNA damage and ADP-ribosylation. Our results demonstrate the unexpected speed at which a global transcriptional response can occur. The findings provide strong support for the residence time of paused Pol II elongation complexes being much shorter than estimated from previous studies.

Evaluation of full S1 gene sequencing of classical and variant infectious bronchitis viruses extracted from allantoic fluid and FTA cards.

Sequence variability in the S1 gene determines the genotype of infectious bronchitis virus (IBV) strains. A single RT-PCR assay was developed to amplify and sequence the full S1 gene for six classical and variant IBVs (M41, D274, 793B, IS/885/00, IS/1494/06 and Q1) enriched in allantoic fluid (AF) or the same AF inoculated onto Flinders Technology Association (FTA) cards. Representative strains from each genotype were grown in specific-pathogen-free eggs and RNA was extracted from AF. Full S1 gene amplification was achieved using primer A and primer 22.51. Products were sequenced using primers A, 1050+, 1380+ and SX3+ to obtain short sequences covering the full gene. Following serial dilutions of AF, detection limits of the partial assay were higher than those of the full S1 gene. Partial S1 sequences exhibited higher-than-average nucleotide similarity percentages (79%; 352 bp) compared to full S1 sequences (77%; 1756 bp), suggesting that full S1 analysis allows greater strain differentiation. For IBV detection from AF-inoculated FTA cards, four serotypes were incubated for up to 21 days at three temperatures, 4°C, room temperature (approximately 24°C) and 40°C. RNA was extracted and tested with partial and full S1 protocols. Through partial sequencing, all IBVs were successfully detected at all sampling points and storage temperatures. In contrast, using full S1 sequencing it was not possible to amplify the gene beyond 14 days or when stored at 40°C. Data presented show that for full S1 sequencing, a substantial amount of RNA is needed. Field samples collected onto FTA cards are unlikely to yield such quantity or quality. ABBREVIATIONS: AF: allantoic fluid; CD50: ciliostatic dose 50; FTA: Flinders Technology Association; IB: infectious bronchitis; IBV: infectious bronchitis virus.

Infectious bronchitis vaccine virus detection and part-S1 genetic variation following single or dual inoculation in broiler chicks.

An investigation was undertaken of the extent of genetic variation occurring within infectious bronchitis virus (IBV) vaccine strains following vaccination of day-old broiler chicks. Chicks were divided into seven groups, with two groups receiving single Massachusetts (Mass) vaccinations while the other four were inoculated with combinations of different IBV serotypes; Mass, 793B, D274 and Arkansas (Ark). The remaining group was maintained as an unvaccinated control. Following vaccination, swabs and tissues collected at intervals were pooled and RNA was extracted for detection of IBV by reverse transcription polymerase chain reaction. Positive amplicons were sequenced for the part-S1 gene and compared to the original vaccine strain sequences. Single nucleotide polymorphisms, amino acid variations and hydrophobicity changes were identified and recorded for each sampling point. A total of 106 single nucleotide polymorphisms were detected within 28 isolates. The average single nucleotide polymorphism counts of swab isolates were greater than those found in tissue samples. This translated into 64 amino acid changes; however only six resulted in a change to the hydrophobicity properties. All hydrophobic alterations occurred within swab isolates and the majority were recovered at 3 days post vaccination suggesting such changes to be detrimental to early virus survival. Nucleotide deletions were seen only in the group given the combination of Mass and Ark. Of the 16 sequenced samples in this group, 13 contained the same AAT deletion at position 1033 1035 in the Ark strains. Findings presented in this study demonstrate alteration in the S1 nucleotide sequence following co-administration of live IBV vaccines.

Tumor Enhancement and Heterogeneity Are Associated With Treatment Response to Drug-Eluting Bead Chemoembolization for Hepatocellular Carcinoma.

PURPOSE: Treatment response to drug-eluting bead chemoembolization (DEB-TACE) is well established for patients with hepatocellular carcinoma (HCC); however, few studies have evaluated tumor imaging characteristics associated with treatment responses. The aim of our study was to identify imaging characteristics associated with treatment responses and overall survival after DEB-TACE of HCC. METHODS: This is a retrospective cohort study of 33 tumors in 32 patients who underwent DEB-TACE for inoperable HCC in a single, large academic medical center. Arterial phase computed tomography data were reviewed to assess tumor size, edge characteristics, tumor enhancement on pixel density histogram, and heterogeneity using coefficient of variation. We assessed correlation between these markers of tumor morphology and response to DEB-TACE using mRECIST criteria, progression-free survival, and overall survival. RESULTS: Tumor heterogeneity (P = 0.01) and tumor enhancement greater than 50% (P = 0.05) were significantly associated with complete response to DEB-TACE in patients with HCC; however, neither was associated with overall or progression-free survival. Tumor size and edge characteristics were not associated with complete response to DEB-TACE, although tumor size greater than 6 cm was associated with worse overall survival (hazard ratio, 3.349; P = 0.02). CONCLUSIONS: Tumor heterogeneity and enhancement on arterial phase imaging may be predictive markers of treatment response to DEB-TACE among patients with HCC.