Altered behavior, brain structure, and neurometabolites in a rat model of autism-specific maternal autoantibody exposure.

Maternal immune dysregulation is a prenatal risk factor for autism spectrum disorder (ASD). Importantly, a clinically relevant connection exists between inflammation and metabolic stress that can result in aberrant cytokine signaling and autoimmunity. In this study we examined the potential for maternal autoantibodies (aAbs) to disrupt metabolic signaling and induce neuroanatomical changes in the brains of exposed offspring. To accomplish this, we developed a model of maternal aAb exposure in rats based on the clinical phenomenon of maternal autoantibody-related ASD (MAR-ASD). Following confirmation of aAb production in rat dams and antigen-specific immunoglobulin G (IgG) transfer to offspring, we assessed offspring behavior and brain structure longitudinally. MAR-ASD rat offspring displayed a reduction in pup ultrasonic vocalizations and a pronounced deficit in social play behavior when allowed to freely interact with a novel partner. Additionally, longitudinal in vivo structural magnetic resonance imaging (sMRI) at postnatal day 30 (PND30) and PND70, conducted in a separate cohort of animals, revealed sex-specific differences in total and regional brain volume. Treatment-specific effects by region appeared to converge on midbrain and cerebellar structures in MAR-ASD offspring. Simultaneously, in vivo 1H magnetic resonance spectroscopy (1H-MRS) data were collected to examine brain metabolite levels in the medial prefrontal cortex. Results showed that MAR-ASD offspring displayed decreased levels of choline-containing compounds and glutathione, accompanied by increased taurine compared to control animals. Overall, we found that rats exposed to MAR-ASD aAbs present with alterations in behavior, brain structure, and neurometabolites; reminiscent of findings observed in clinical ASD.

Association Between End-Stage Liver Disease and Incident Heart Failure in an Integrated Health System.

BACKGROUND: End-stage liver disease (ESLD) and heart failure (HF) often coexist and are associated with significant morbidity and mortality. However, the true incidence of HF among patients with ESLD remains understudied. OBJECTIVE: This study aims to evaluate the association between ESLD and incident HF in a real-world clinical cohort. DESIGN AND PARTICIPANTS: A retrospective electronic health records database analysis of individuals with ESLD and frequency-matched controls without ESLD in a large integrated health system. MAIN MEASURES: The primary outcome was incident HF, which was defined by the International Classification of Disease codes and manually adjudicated by physician reviewers. The Kaplan-Meier method was used to estimate the cumulative incidence of HF. Multivariate proportional hazards models adjusted for shared metabolic factors (diabetes, hypertension, chronic kidney disease, coronary heart disease, body mass index) were used to compare the risk of HF in patients with and without ESLD. KEY RESULTS: Of 5004 patients (2502 with ESLD and 2502 without ESLD), the median (Q1-Q3) age was 57.0 (55.0-65.0) years, 59% were male, and 18% had diabetes. Over a median (Q1-Q3) follow-up of 2.3 (0.6-6.0) years, 121 incident HF cases occurred. Risk for incident HF was significantly higher for patients with ESLD compared with the non-ESLD group (adjusted HR: 4.67; 95% CI: 2.82-7.75; p < 0.001), with the majority of the ESLD group (70.7%) having HF with preserved ejection fraction (ejection fraction ≥ 50%). CONCLUSION: ESLD was significantly associated with a higher risk of incident HF, independent of shared metabolic risk factors, with the predominant phenotype being HF with preserved ejection fraction.

Sexually dimorphic neuroanatomical differences relate to ASD-relevant behavioral outcomes in a maternal autoantibody mouse model.

Immunoglobulin G (IgG) autoantibodies reactive to fetal brain proteins in mothers of children with ASD have been described by several groups. To understand their pathologic significance, we developed a mouse model of maternal autoantibody related ASD (MAR-ASD) utilizing the peptide epitopes from human autoantibody reactivity patterns. Male and female offspring prenatally exposed to the salient maternal autoantibodies displayed robust deficits in social interactions and increased repetitive self-grooming behaviors as juveniles and adults. In the present study, neuroanatomical differences in adult MAR-ASD and control offspring were assessed via high-resolution ex vivo magnetic resonance imaging (MRI) at 6 months of age. Of interest, MAR-ASD mice displayed significantly larger total brain volume and of the 159 regions examined, 31 were found to differ significantly in absolute volume (mm3) at an FDR of <5%. Specifically, the absolute volumes of several white matter tracts, cortical regions, and basal nuclei structures were significantly increased in MAR-ASD animals. These phenomena were largely driven by female MAR-ASD offspring, as no significant differences were seen with either absolute or relative regional volume in male MAR-ASD mice. However, structural covariance analysis suggests network-level desynchronization in brain volume in both male and female MAR-ASD mice. Additionally, preliminary correlational analysis with behavioral data relates that volumetric increases in numerous brain regions of MAR-ASD mice were correlated with social interaction and repetitive self-grooming behaviors in a sex-specific manner. These results demonstrate significant sex-specific effects in brain size, regional relationships, and behavior for offspring prenatally exposed to MAR-ASD autoantibodies relative to controls.

Hepatitis delta genotype 5 is associated with favourable disease outcome and better response to treatment compared to genotype 1.

BACKGROUND & AIMS: Coinfection with HDV causes rapid progression to liver cirrhosis and hepatic decompensation in patients with chronic hepatitis B. Factors that are associated with disease progression are poorly understood. In this study we aim to identify risk factors associated with disease progression and better characterise clinical differences and treatment response between HDV genotype 1 and 5. METHODS: In this retrospective study, all patients under our care between 2005 and 2016 with HBV/HDV coinfection (HBsAg+, anti-HDV antibodies positive) were analysed. Patients were excluded if follow-up was less than 6 months, if they had HCV and/or HIV coinfection or an acute HDV infection. Demographic data, stage of liver disease, development of liver complications and treatment response were recorded. RESULTS: One-hundred seven patients (mean age 36.0 years, 57% male) were followed for a median period of 4.4 years (range 0.6-28.1 years); 64% were of African origin and 17% were of European origin, with 28% of patients being cirrhotic at first visit; 43% patients had actively replicating HDV virus (anti-HDV-IgG+, anti-HDV-IgM+ or HDV RNA+) and 57% of patients were HDV exposed (anti-HDV-IgG+, HDV RNA-). Patients with actively replicating HDV more often developed liver complications than HDV-exposed patients (p = 0.002), but no differences in baseline characteristics were observed. Patients with HDV genotype 5 less often developed cirrhosis or hepatic decompensation compared to patients with HDV genotype 1. Twenty-four patients were treated with peg-IFN and post-treatment response was significantly better in patients infected with genotype 5 (10% GT1 vs. 64% GT5, p = 0.013). CONCLUSION: Patients infected with HDV genotype 5 appear to have a better prognosis with fewer episodes of hepatic decompensation and better response to peg-IFN treatment than patients infected with HDV genotype 1. LAY SUMMARY: Hepatitis delta is a virus that affects the liver. The virus is known to have different subtypes, called genotypes. With this research we discovered that hepatitis delta virus genotype 1 behaves differently than genotype 5 and causes faster development of liver disease. This is important for education of our patients and to determine how often we need to check our patients.

Three-dimensional US for Quantification of Volumetric Blood Flow: Multisite Multisystem Results from within the Quantitative Imaging Biomarkers Alliance.

Background Quantitative blood flow (QBF) measurements that use pulsed-wave US rely on difficult-to-meet conditions. Imaging biomarkers need to be quantitative and user and machine independent. Surrogate markers (eg, resistive index) fail to quantify actual volumetric flow. Standardization is possible, but relies on collaboration between users, manufacturers, and the U.S. Food and Drug Administration. Purpose To evaluate a Quantitative Imaging Biomarkers Alliance-supported, user- and machine-independent US method for quantitatively measuring QBF. Materials and Methods In this prospective study (March 2017 to March 2019), three different clinical US scanners were used to benchmark QBF in a calibrated flow phantom at three different laboratories each. Testing conditions involved changes in flow rate (1-12 mL/sec), imaging depth (2.5-7 cm), color flow gain (0%-100%), and flow past a stenosis. Each condition was performed under constant and pulsatile flow at 60 beats per minute, thus yielding eight distinct testing conditions. QBF was computed from three-dimensional color flow velocity, power, and scan geometry by using Gauss theorem. Statistical analysis was performed between systems and between laboratories. Systems and laboratories were anonymized when reporting results. Results For systems 1, 2, and 3, flow rate for constant and pulsatile flow was measured, respectively, with biases of 3.5% and 24.9%, 3.0% and 2.1%, and -22.1% and -10.9%. Coefficients of variation were 6.9% and 7.7%, 3.3% and 8.2%, and 9.6% and 17.3%, respectively. For changes in imaging depth, biases were 3.7% and 27.2%, -2.0% and -0.9%, and -22.8% and -5.9%, respectively. Respective coefficients of variation were 10.0% and 9.2%, 4.6% and 6.9%, and 10.1% and 11.6%. For changes in color flow gain, biases after filling the lumen with color pixels were 6.3% and 18.5%, 8.5% and 9.0%, and 16.6% and 6.2%, respectively. Respective coefficients of variation were 10.8% and 4.3%, 7.3% and 6.7%, and 6.7% and 5.3%. Poststenotic flow biases were 1.8% and 31.2%, 5.7% and -3.1%, and -18.3% and -18.2%, respectively. Conclusion Interlaboratory bias and variation of US-derived quantitative blood flow indicated its potential to become a clinical biomarker for the blood supply to end organs. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Forsberg in this issue.

Transcutaneous contrast-enhanced ultrasound imaging of the posttraumatic spinal cord.

STUDY DESIGN: Experimental animal study. OBJECTIVE: The current study aims to test whether the blood flow within the contused spinal cord can be assessed in a rodent model via the acoustic window of the laminectomy utilizing transcutaneous ultrasound. SETTING: Department of Neurological Surgery, University of Washington, Seattle WA. METHODS: Long-Evans rats (n = 12) were subjected to a traumatic thoracic spinal cord injury (SCI). Three days and 10 weeks after injury, animals underwent imaging of the contused spinal cord using ultrafast contrast-enhanced ultrasound with a Vantage ultrasound research system in combination with a 15 MHz transducer. Lesion size and signal-to-noise ratios were estimated via transcutaneous, subcutaneous, or epidural ultrasound acquisition through the acoustic window created by the original laminectomy. RESULTS: Following laminectomy, transcutaneous and subcutaneous contrast-enhanced ultrasound imaging allowed for assessment of perfusion and vascular flow in the contused rodent spinal cord. An average loss of 7.2 dB from transcutaneous to subcutaneous and the loss of 5.1 dB from subcutaneous to epidural imaging in signal-to-noise ratio (SNR) was observed. The hypoperfused injury center was measured transcutaneously, subcutaneously and epidurally (5.78 ± 0.86, 5.91 ± 0.53, 5.65 ± 1.07 mm2) at 3 days post injury. The same animals were reimaged again at 10 weeks following SCI, and the area of hypoperfusion had decreased significantly compared with the 3-day measurements detected via transcutaneous, subcutaneous, and epidural imaging respectively (0.69 ± 0.05, 1.09 ± 0.11, 0.95 ± 0.11 mm2, p < 0.001). CONCLUSIONS: Transcutaneous ultrasound allows for measurements and longitudinal monitoring of local hemodynamic changes in a rodent SCI model.

Spontaneous Nucleation of Stable Perfluorocarbon Emulsions for Ultrasound Contrast Agents.

Phase-change contrast agents are rapidly developing as an alternative to microbubbles for ultrasound imaging and therapy. These agents are synthesized and delivered as liquid droplets and vaporized locally to produce image contrast. They can be used like conventional microbubbles but with the added benefit of reduced size and improved stability. Droplet-based agents can be synthesized with diameters on the order of 100 nm, making them an ideal candidate for extravascular imaging or therapy. However, their synthesis requires low boiling point perfluorocarbons (PFCs) to achieve activation (i.e., vaporization) thresholds within FDA approved limits. Minimizing spontaneous vaporization while producing liquid droplets using conventional methods with low boiling point PFCs can be challenging. In this study, a new method to produce PFC nanodroplets using spontaneous nucleation is demonstrated using PFCs with boiling points ranging from -37 to 56 °C. Sometimes referred to as the ouzo method, the process relies on saturating a cosolvent with the PFC before adding a poor solvent to reduce solvent quality, forcing droplets to spontaneously nucleate. This approach can produce droplets ranging from under 100 nm to over 1 µm in diameter. Ternary plots showing solvent and PFC concentrations leading to droplet nucleation are presented. Additionally, acoustic activation thresholds and size distributions with varying PFC and solvent conditions are measured and discussed. Finally, ultrasound contrast imaging is demonstrated using ouzo droplets in an animal model.

Psychologically informed practice (PIP) within the offender personality disorder pathway: Towards establishing an evidence base for approved premises.

The United Kingdom (UK) government has commissioned numerous interventions across all stages of the criminal justice pathway for managing offenders likely to have a personality disorder, with the intention to reduce reoffending, improve psychological wellbeing, and develop workforce capabilities. Psychologically Informed Practice (PIP) models underpin these. To evaluate a modified PIP model within the post-imprisonment community stage of the Offender Personality Disorder (OPD) pathway, specifically workforce development, within all London (UK) probation supervised hostels (approved premises), we used both non-equivalent control group and pre-post repeated measure designs to compare changes in staff and offender outcomes before and after introduction of a PIP model across all 12 London approved premises. Findings revealed statistically significant improvements in a number of workforce outcomes (measured using the Personality Disorder - Knowledge, Attitudes and Skills Questionnaire and Maslach Burnout Inventory) which were moderated by age and gender. Data did not support associated improvements in resident offender outcomes (progressive moves, rearrests/reoffences, or breaches leading to recalls). The modified PIP is an effective intervention model for improving some workforce outcomes among probation supervised hostel staff, particularly for women, but our findings suggest that intervention development may be required for significant improvements to be observed in resident offending outcomes. In addition, further research is necessary to determine the longer term effects of PIP on absenteeism, employee turnover, quality of resident-staff interactions, and overall culture change among staff working within the post-imprisonment community stage of the OPD pathway.

Acute peripheral immune activation alters cytokine expression and glial activation in the early postnatal rat brain.

BACKGROUND: Neuroinflammation can modulate brain development; however, the influence of an acute peripheral immune challenge on neuroinflammatory responses in the early postnatal brain is not well characterized. To address this gap in knowledge, we evaluated the peripheral and central nervous system (CNS) immune responses to a mixed immune challenge in early postnatal rats of varying strains and sex. METHODS: On postnatal day 10 (P10), male and female Lewis and Brown Norway rats were injected intramuscularly with either a mix of bacterial and viral components in adjuvant, adjuvant-only, or saline. Immune responses were evaluated at 2 and 5 days post-challenge. Cytokine and chemokine levels were evaluated in serum and in multiple brain regions using a Luminex multiplex assay. Multi-factor ANOVAs were used to compare analyte levels across treatment groups within strain, sex, and day of sample collection. Numbers and activation status of astrocytes and microglia were also analyzed in the cortex and hippocampus by quantifying immunoreactivity for GFAP, IBA-1, and CD68 in fixed brain slices. Immunohistochemical data were analyzed using a mixed-model regression analysis. RESULTS: Acute peripheral immune challenge differentially altered cytokine and chemokine levels in the serum versus the brain. Within the brain, the cytokine and chemokine response varied between strains, sexes, and days post-challenge. Main findings included differences in T helper (Th) type cytokine responses in various brain regions, particularly the cortex, with respect to IL-4, IL-10, and IL-17 levels. Additionally, peripheral immune challenge altered GFAP and IBA-1 immunoreactivity in the brain in a strain- and sex-dependent manner. CONCLUSIONS: These findings indicate that genetic background and sex influence the CNS response to an acute peripheral immune challenge during early postnatal development. Additionally, these data reinforce that the developmental time point during which the challenge occurs has a distinct effect on the activation of CNS-resident cells.

Can quantitative hepatitis B surface antigen levels predict the severity of liver disease in genotype E Patients?

The utility of quantitative Hepatitis B surface antigen (qHBsAg) level as a marker of chronic hepatitis B (CHB)-related liver damage is not fully delineated, but is becoming increasingly relevant. Quantitative HBsAg levels are linked with progression of liver disease in HBeAg-negative genotype B and C patients, but it is not clear whether this is consistent across all HBV genotypes. In this single-centre, cross-sectional observational study, we evaluated whether qHBsAg levels can predict the severity of liver disease in genotype E patients. Demographic characteristics, viral, biochemical markers and qHBsAg levels were assessed at time of liver biopsy [all HBV DNA>2000 IU/mL and/or abnormal alanine transaminase (ALT)]. Patients were divided into three groups according to the severity of fibrosis on biopsy: mild (F0-1), moderate (F2-4), severe (F5-6) liver disease and into two groups according to the NI grading, low (NI 0-3) and high inflammation (NI ≥4). A total of 259 HBeAg-negative CHB treatment-naive genotype E patients were studied. The median age of this cohort was 38 years, and 61% were males. Advanced (severe) fibrosis patients had higher ALT, HBV DNA, and lower HBsAg level and qHBsAg/DNA ratio. Patients with NI ≥4 had higher ALT, HBV DNA, but lower qHBsAg/DNA ratio. There was no correlation between HBsAg and HBV DNA levels. Quantitative HBsAg levels were lower in more advanced liver fibrosis. There was no correlation between qHBsAg and HBV DNA levels. This may reflect discordance between viral replication and transcriptional activity or differential HBsAg expression in HBeAg-negative genotype E patients with advanced liver disease.

A condition metric for Eucalyptus woodland derived from expert evaluations.

The evaluation of ecosystem quality is important for land-management and land-use planning. Evaluation is unavoidably subjective, and robust metrics must be based on consensus and the structured use of observations. We devised a transparent and repeatable process for building and testing ecosystem metrics based on expert data. We gathered quantitative evaluation data on the quality of hypothetical grassy woodland sites from experts. We used these data to train a model (an ensemble of 30 bagged regression trees) capable of predicting the perceived quality of similar hypothetical woodlands based on a set of 13 site variables as inputs (e.g., cover of shrubs, richness of native forbs). These variables can be measured at any site and the model implemented in a spreadsheet as a metric of woodland quality. We also investigated the number of experts required to produce an opinion data set sufficient for the construction of a metric. The model produced evaluations similar to those provided by experts, as shown by assessing the model's quality scores of expert-evaluated test sites not used to train the model. We applied the metric to 13 woodland conservation reserves and asked managers of these sites to independently evaluate their quality. To assess metric performance, we compared the model's evaluation of site quality with the managers' evaluations through multidimensional scaling. The metric performed relatively well, plotting close to the center of the space defined by the evaluators. Given the method provides data-driven consensus and repeatability, which no single human evaluator can provide, we suggest it is a valuable tool for evaluating ecosystem quality in real-world contexts. We believe our approach is applicable to any ecosystem.

Assessing fire impacts on the carbon stability of fire-tolerant forests.

The carbon stability of fire-tolerant forests is often assumed but less frequently assessed, limiting the potential to anticipate threats to forest carbon posed by predicted increases in forest fire activity. Assessing the carbon stability of fire-tolerant forests requires multi-indicator approaches that recognize the myriad ways that fires influence the carbon balance, including combustion, deposition of pyrogenic material, and tree death, post-fire decomposition, recruitment, and growth. Five years after a large-scale wildfire in southeastern Australia, we assessed the impacts of low- and high-severity wildfire, with and without prescribed fire (≤10 yr before), on carbon stocks in multiple pools, and on carbon stability indicators (carbon stock percentages in live trees and in small trees, and carbon stocks in char and fuels) in fire-tolerant eucalypt forests. Relative to unburned forest, high-severity wildfire decreased short-term (five-year) carbon stability by significantly decreasing live tree carbon stocks and percentage stocks in live standing trees (reflecting elevated tree mortality), by increasing the percentage of live tree carbon in small trees (those vulnerable to the next fire), and by potentially increasing the probability of another fire through increased elevated fine fuel loads. In contrast, low-severity wildfire enhanced carbon stability by having negligible effects on aboveground stocks and indicators, and by significantly increasing carbon stocks in char and, in particular, soils, indicating pyrogenic carbon accumulation. Overall, recent preceding prescribed fire did not markedly influence wildfire effects on short-term carbon stability at stand scales. Despite wide confidence intervals around mean stock differences, indicating uncertainty about the magnitude of fire effects in these natural forests, our assessment highlights the need for active management of carbon assets in fire-tolerant eucalypt forests under contemporary fire regimes. Decreased live tree carbon and increased reliance on younger cohorts for carbon recovery after high-severity wildfire could increase vulnerabilities to imminent fires, leading to decisions about interventions to maintain the productivity of some stands. Our multi-indicator assessment also highlights the importance of considering all carbon pools, particularly pyrogenic reservoirs like soils, when evaluating the potential for prescribed fire regimes to mitigate the carbon costs of wildfires in fire-prone landscapes.

Do multiple fires interact to affect vegetation structure in temperate eucalypt forests?

Fire plays an important role in structuring vegetation in fire-prone regions worldwide. Progress has been made towards documenting the effects of individual fire events and fire regimes on vegetation structure; less is known of how different fire history attributes (e.g., time since fire, fire frequency) interact to affect vegetation. Using the temperate eucalypt foothill forests of southeastern Australia as a case study system, we examine two hypotheses about such interactions: (1) post-fire vegetation succession (e.g., time-since-fire effects) is influenced by other fire regime attributes and (2) the severity of the most recent fire overrides the effect of preceding fires on vegetation structure. Empirical data on vegetation structure were collected from 540 sites distributed across central and eastern Victoria, Australia. Linear mixed models were used to examine these hypotheses and determine the relative influence of fire and environmental attributes on vegetation structure. Fire history measures, particularly time since fire, affected several vegetation attributes including ground and canopy strata; others such as low and sub-canopy vegetation were more strongly influenced by environmental characteristics like rainfall. There was little support for the hypothesis that post-fire succession is influenced by fire history attributes other than time since fire; only canopy regeneration was influenced by another variable (fire type, representing severity). Our capacity to detect an overriding effect of the severity of the most recent fire was limited by a consistently weak effect of preceding fires on vegetation structure. Overall, results suggest the primary way that fire affects vegetation structure in foothill forests is via attributes of the most recent fire, both its severity and time since its occurrence; other attributes of fire regimes (e.g., fire interval, frequency) have less influence. The strong effect of environmental drivers, such as rainfall and topography, on many structural features show that foothill forest vegetation is also influenced by factors outside human control. While fire is amenable to human management, results suggest that at broad scales, structural attributes of these forests are relatively resilient to the effects of current fire regimes. Nonetheless, the potential for more frequent severe fires at short intervals, associated with a changing climate and/or fire management, warrant further consideration.

Individual consistency and flexibility in human social information use.

Copying others appears to be a cost-effective way of obtaining adaptive information, particularly when flexibly employed. However, adult humans differ considerably in their propensity to use information from others, even when this 'social information' is beneficial, raising the possibility that stable individual differences constrain flexibility in social information use. We used two dissimilar decision-making computer games to investigate whether individuals flexibly adjusted their use of social information to current conditions or whether they valued social information similarly in both games. Participants also completed established personality questionnaires. We found that participants demonstrated considerable flexibility, adjusting social information use to current conditions. In particular, individuals employed a 'copy-when-uncertain' social learning strategy, supporting a core, but untested, assumption of influential theoretical models of cultural transmission. Moreover, participants adjusted the amount invested in their decision based on the perceived reliability of personally gathered information combined with the available social information. However, despite this strategic flexibility, participants also exhibited consistent individual differences in their propensities to use and value social information. Moreover, individuals who favoured social information self-reported as more collectivist than others. We discuss the implications of our results for social information use and cultural transmission.

CXCL10 levels identify individuals with rapid fibrosis at 12 months post-transplant for hepatitis C virus and predict treatment response.

BACKGROUNDS: Recurrent hepatitis C virus (HCV) infection is universal post-transplantation. Fibrosis (F) stage ≥2 at 12 months identifies patients with rapid fibrosis progression. Antiviral therapy (AVT) remains the only option to attenuate fibrosis progression. We hypothesized that CXCL10 levels can distinguish between slow and fast fibrosis progression at 12 months, development of F ≥ 4 post-transplantation, and help predict treatment response in patients undergoing AVT. METHODS: All patients that had undergone primary liver transplantation at King's College Hospital, London, between 2000 and 2011 were identified. Quantification of CXCL10 was performed using an ELISA-based assay on stored plasma at six months post-transplant and pre-treatment. Comparison was made with liver biopsies performed at 12 months and in the post-transplant period where available. RESULTS: One hundred and thirty-three patients were included. CXCL10 levels were lower in the slow fibrosis group compared to the rapid fibrosis group (p < 0.0001). CXCL10 correlated with F stage, necro-inflammatory score, and serum transaminases (<0.0001). CXCL10 was an independent predictor of F ≥ 2 at 12 months and F ≥ 4 (p < 0.05). Pre-treatment CXCL10 levels were an independent predictor of sustained virologic response (p = 0.04). CONCLUSIONS: CXCL10 levels help identify patients with rapid fibrosis progression in patients with recurrent HCV and those that are likely to respond to AVT.

Excess neonatal testosterone causes male-specific social and fear memory deficits in wild-type mice.

Neurodevelopmental disorders (ND) disproportionately affect males compared to females, and Autism Spectrum Disorder (ASD) in particular exhibits a 4:1 male bias. The biological mechanisms of this female protection or male susceptibility have not been identified. There is some evidence to suggest that fetal/neonatal gonadal hormones, which play pivotal roles in many aspects of development, may contribute. Here, we investigate the role of testosterone administration during a critical period of development, and its effects on social approach and fear learning in C57BL/6J wildtype mice. Male, but not female mice treated with testosterone on the day of birth (PN0) exhibited deficits in both social behavior and contextual fear conditioning, whereas mice treated with the same dose of testosterone on postnatal day 18 (PN18) did not display such impairments. Testosterone administration did not induce anxiogenic effects or lead to changes in body weight compared to the vehicle-treated group. These impairmeants are relevant to ND and may help identify novel treatment targets.

Contrast-enhanced ultrasound imaging detects anatomical and functional changes in rat cervical spine microvasculature with normal aging.

Normal aging is associated with significant deleterious cerebrovascular changes; these have been implicated in disease pathogenesis and increased susceptibility to ischemic injury. While these changes are well documented in the brain, few studies have been conducted in the spinal cord. Here, we utilize specialized contrast-enhanced ultrasound (CEUS) imaging to investigate age-related changes in cervical spinal vascular anatomy and hemodynamics in male Fisher 344 rats, a common strain in aging research. Aged rats (24-26 mo., N=6) exhibited significant tortuosity in the anterior spinal artery and elevated vascular resistance compared to adults (4-6 mo., N=6; tortuosity index 2.20±0.15 vs 4.74±0.45, p<0.05). Baseline blood volume was lower in both larger vessels and the microcirculation in the aged cohort, specifically in white matter (4.44e14±1.37e13 vs 3.66e14±2.64e13 CEUS bolus AUC, p<0.05). To elucidate functional differences, animals were exposed to a hypoxia challenge; whereas adult rats exhibited significant functional hyperemia in both gray and white matter (GM: 1.13±0.10-fold change from normoxia, p<0.05; WM: 1.16±0.13, p<0.05), aged rats showed no response. Immunohistochemistry revealed reduced pericyte coverage and activated microglia behavior in aged rats, which may partially explain the lack of vascular response. This study provides the first in vivo description of age-related hemodynamic differences in the cervical spinal cord.

Quantifying injury expansion in the cervical spinal cord with intravital ultrafast contrast-enhanced ultrasound imaging.

Spinal cord injury is characterized by hemodynamic disruption at the injury epicenter and hypoperfusion in the penumbra, resulting in progressive ischemia and cell death. This degenerative secondary injury process has been well-described, though mostly using ex vivo or depth-limited optical imaging techniques. Intravital contrast-enhanced ultrasound enables longitudinal, quantitative evaluation of anatomical and hemodynamic changes in vivo through the entire spinal parenchyma. Here, we used ultrasound imaging to visualize and quantify subacute injury expansion (through 72 h post-injury) in a rodent cervical contusion model. Significant intraparenchymal hematoma expansion was observed through 72 h post-injury (1.86 ± 0.17-fold change from acute, p < 0.05), while the volume of the ischemic deficit largely increased within 24 h post-injury (2.24 ± 0.27-fold, p < 0.05). Histology corroborated these findings; increased apoptosis, tissue and vessel loss, and sustained tissue hypoxia were observed at 72 h post-injury. Vascular resistance was significantly elevated in the remaining perfused tissue, likely due in part to deformation of the central sulcal artery nearest to the lesion site. In conjunction, substantial hyperemia was observed in all perilesional areas examined except the ipsilesional gray matter. This study demonstrates the utility of longitudinal ultrasound imaging as a quantitative tool for tracking injury progression in vivo.

Source and characterization of hepatic macrophages in acetaminophen-induced acute liver failure in humans.

UNLABELLED: Acetaminophen-induced acute liver failure (AALF) is associated with innate immunity activation, which contributes to the severity of hepatic injury and clinical outcome. A marked increase in hepatic macrophages (h-mφ) is observed in experimental models of AALF, but controversy exists regarding their role, implicating h-mφ in both aggravation and resolution of liver injury. The role of h-mφ in human AALF is virtually unexplored. We sought to investigate the role of chemokine (C-C motif) ligand 2 (CCL2) in the recruitment of circulating monocytes to the inflamed liver and to determine how the h-mφ infiltrate and liver microenvironment may contribute to tissue repair versus inflammation in AALF. We evaluated circulating monocytes, their chemokine (C-C motif) receptor 2 (CCR2) expression, and serum CCL2 levels in patients with AALF. Cell subsets and numbers of circulation-derived (MAC387+) or resident proliferating (CD68/Ki67+) h-mφ in hepatic immune infiltrates were determined by immunohistochemistry. Inflammatory cytokine levels were determined in whole and laser microdissected liver tissue by proteome array. In AALF, circulating monocytes were depleted, with the lowest levels observed in patients with adverse outcomes. CCL2 levels were high in AALF serum and hepatic tissue, and circulating monocyte subsets expressed CCR2, suggesting CCL2-dependent hepatic monocyte recruitment. Significant numbers of both MAC387+ and CD68+ h-mφ were found in AALF compared with control liver tissue with a high proportion expressing the proliferation marker Ki67. Levels of CCL2, CCL3, interleukin (IL)-6, IL-10, and transforming growth factor-ß1 were significantly elevated in AALF liver tissue relative to chronic liver disease controls. CONCLUSION: In AALF, the h-mφ population is expanded in areas of necrosis, both through proliferation of resident cells and CCL2-dependent recruitment of circulating monocytes. The presence of h-mφ within an anti-inflammatory/regenerative microenvironment indicates that they are implicated in resolution of inflammation/tissue repair processes during AALF.

A new method for producing transgenic birds via direct in vivo transfection of primordial germ cells.

Traditional methods of avian transgenesis involve complex manipulations involving either retroviral infection of blastoderms or the ex vivo manipulation of primordial germ cells (PGCs) followed by injection of the cells back into a recipient embryo. Unlike in mammalian systems, avian embryonic PGCs undergo a migration through the vasculature on their path to the gonad where they become the sperm or ova producing cells. In a development which simplifies the procedure of creating transgenic chickens we have shown that PGCs are directly transfectable in vivo using commonly available transfection reagents. We used Lipofectamine 2000 complexed with Tol2 transposon and transposase plasmids to stably transform PGCs in vivo generating transgenic offspring that express a reporter gene carried in the transposon. The process has been shown to be highly effective and as robust as the other methods used to create germ-line transgenic chickens while substantially reducing time, infrastructure and reagents required. The method described here defines a simple direct approach for transgenic chicken production, allowing researchers without extensive PGC culturing facilities or skills with retroviruses to produce transgenic chickens for wide-ranging applications in research, biotechnology and agriculture.