Prevalence of Cerebral Microhemorrhage following Chronic Blast-Related Mild Traumatic Brain Injury in Military Service Members Using Susceptibility-Weighted MRI

BACKGROUND AND PURPOSE

Cerebral microhemorrhages are a known marker of mild traumatic brain injury. Blast-related mild traumatic brain injury relates to a propagating pressure wave, and there is evidence that the mechanism of injury in blast-related mild traumatic brain injury may be different from that in blunt head trauma. Two recent reports in mixed cohorts of blunt and blast-related traumatic brain injury in military personnel suggest that the prevalence of cerebral microhemorrhages is lower than in civilian head injury. In this study, we aimed to characterize the prevalence of cerebral microhemorrhages in military service members specifically with chronic blast-related mild traumatic brain injury.

MATERIALS AND METHODS

Participants were prospectively recruited and underwent 3T MR imaging. Susceptibility-weighted images were assessed by 2 neuroradiologists independently for the presence of cerebral microhemorrhages.

RESULTS

Our cohort included 146 veterans (132 men) who experienced remote blast-related mild traumatic brain injury (mean, 9.4 years; median, 9 years after injury). Twenty-one (14.4%) reported loss of consciousness for <30 minutes. Seventy-seven subjects (52.7%) had 1 episode of blast-related mild traumatic brain injury; 41 (28.1%) had 2 episodes; and 28 (19.2%) had >2 episodes. No cerebral microhemorrhages were identified in any subject, as opposed to the frequency of SWI-detectable cerebral microhemorrhages following blunt-related mild traumatic brain injury in the civilian population, which has been reported to be as high as 28% in the acute and subacute stages.

CONCLUSIONS

Our results may reflect differences in pathophysiology and the mechanism of injury between blast- and blunt-related mild traumatic brain injury. Additionally, the chronicity of injury may play a role in the detection of cerebral microhemorrhages.

Anti-microbial stewardship: antibiotic use in well-appearing term neonates born to mothers with chorioamnionitis

OBJECTIVE

To determine if implementation of a protocol based on a neonatal early-onset sepsis (EOS) calculator developed by Kaiser Permanente would safely reduce antibiotic use in well-appearing term infants born to mothers with chorioamnionitis in the unique setting of an Observation Nursery.

STUDY DESIGN

Data obtained from a retrospective chart review of well-appearing term infants born between 2009 and 2016 were entered into the EOS calculator to obtain management recommendations.

RESULTS

Three hundred and sixty-two infants met the study criteria. Management according to the EOS calculator would reduce antibiotic use from 99% to 2.5% (P<0.0001) of patients. Average length of therapy would also decrease from 2.08 to 0.05 days (P<0.0001). One infant, who remained asymptomatic, had Enterococcus bacteremia and received a 7-day course of broad-spectrum antibiotics.

CONCLUSIONS

Culture-positive sepsis in asymptomatic neonates born to mothers with chorioamnionitis is rare. Management according to the EOS calculator would markedly reduce the potential complications of antibiotic use. These data should initiate re-examination of existing protocols for management of this cohort of patients.

Canine babesiosis and tick activity monitored using companion animal electronic health records in the UK

Recent publications highlighting autochthonous Babesia canis infection in dogs from Essex that have not travelled outside the UK are a powerful reminder of the potential for pathogen emergence in new populations. Here the authors use electronic health data collected from two diagnostic laboratories and a network of 392 veterinary premises to describe canine Babesia cases and levels of Babesia concern from January 2015 to March 2016, and the activity of ticks during December 2015–March 2016. In most areas of the UK, Babesia diagnosis in this population was rare and sporadic. In addition, there was a clear focus of Babesia cases in the affected area in Essex. Until February 2016, analysis of health records indicated only sporadic interest in Babesia largely in animals coming from overseas. Following media coverage in March 2016, there was a spike in owner concern that was geographically dispersed beyond the at-risk area. Tick activity (identified as ticks being removed from animals in veterinary consultations) was consistent but low during the period preceding the infections (<5 ticks/10,000 consultations), but increased in March. This highlights the use of electronic health data to describe rapidly evolving risk and concern that follows the emergence of a pathogen.

Understanding the controls on deposited fine sediment in the streams of agricultural catchments

Excessive sediment pressure on aquatic habitats is of global concern. A unique dataset, comprising instantaneous measurements of deposited fine sediment in 230 agricultural streams across England and Wales, was analysed in relation to 20 potential explanatory catchment and channel variables. The most effective explanatory variable for the amount of deposited sediment was found to be stream power, calculated for bankfull flow and used to index the capacity of the stream to transport sediment. Both stream power and velocity category were highly significant (p ≪ 0.001), explaining some 57% variation in total fine sediment mass. Modelled sediment pressure, predominantly from agriculture, was marginally significant (p<0.05) and explained a further 1% variation. The relationship was slightly stronger for erosional zones, providing 62% explanation overall. In the case of the deposited surface drape, stream power was again found to be the most effective explanatory variable (p<0.001) but velocity category, baseflow index and modelled sediment pressure were all significant (p<0.01); each provided an additional 2% explanation to an overall 50%. It is suggested that, in general, the study sites were transport-limited and the majority of stream beds were saturated by fine sediment. For sites below saturation, the upper envelope of measured fine sediment mass increased with modelled sediment pressure. The practical implications of these findings are that (i) targets for fine sediment loads need to take into account the ability of streams to transport/retain fine sediment, and (ii) where agricultural mitigation measures are implemented to reduce delivery of sediment, river management to mobilise/remove fines may also be needed in order to effect an improvement in ecological status in cases where streams are already saturated with fines and unlikely to self-cleanse.

Integrative review on the non-invasive management of lower urinary tract symptoms in men following treatments for pelvic malignancies

AIM

To develop a non-invasive management strategy for men with lower urinary tract symptoms (LUTS) after treatment for pelvic cancer, that is suitable for use in a primary healthcare context.

METHODS

PubMed literature searches of LUTS management in this patient group were carried out, together with obtaining a consensus of management strategies from a panel of authors for the management of LUTS from across the UK.

RESULTS

Data from 41 articles were investigated and collated. Clinical experience was sought from authors where there was no clinical evidence. The findings discussed in this paper confirm that LUTS after the cancer treatment can significantly impair men's quality of life. While many men recover from LUTS spontaneously over time, a significant proportion require long-term management. Despite the prevalence of LUTS, there is a lack of consensus on best management. This article offers a comprehensive treatment algorithm to manage patients with LUTS following pelvic cancer treatment.

CONCLUSION

Based on published research literature and clinical experience, recommendations are proposed for the standardisation of management strategies employed for men with LUTS after the pelvic cancer treatment. In addition to implementing the algorithm, understanding the rationale for the type and timing of LUTS management strategies is crucial for clinicians and patients.

Low-Cost, High-Throughput Sequencing of DNA Assemblies Using a Highly Multiplexed Nextera Process

In recent years, next-generation sequencing (NGS) technology has greatly reduced the cost of sequencing whole genomes, whereas the cost of sequence verification of plasmids via Sanger sequencing has remained high. Consequently, industrial-scale strain engineers either limit the number of designs or take short cuts in quality control. Here, we show that over 4000 plasmids can be completely sequenced in one Illumina MiSeq run for less than $3 each (15× coverage), which is a 20-fold reduction over using Sanger sequencing (2× coverage). We reduced the volume of the Nextera tagmentation reaction by 100-fold and developed an automated workflow to prepare thousands of samples for sequencing. We also developed software to track the samples and associated sequence data and to rapidly identify correctly assembled constructs having the fewest defects. As DNA synthesis and assembly become a centralized commodity, this NGS quality control (QC) process will be essential to groups operating high-throughput pipelines for DNA construction.

Removal of viral contaminants by monoclonal antibody purification of plasma proteins

The transmittance of pathogenic viruses by the widespread administration of protein fractions such as F VIII prepared on a large scale from pooled human plasma has been of growing concern. We have now demonstrated that significant amounts of pathogenic viruses including LAV/HTLVIII may be removed by a new large scale fractionation process for the preparation of human F VIII (Monoclate) which employs immunoaffinity chromatography. Model viruses representative of different virus families and the LAV strain of HIV were added to cryoprecipitate and then the mixture was processed as for Monoclate manufacturing. Virus titers were determined at each step of the fractionation procedures. An overall reduction of at least 6 logs was obtained for the model viruses and the HIV due to the purification process. An added heating step further increased the safety margin for the product resulting in at least an overall reduction of 7-9 logs for HIV. Clinical experience with Monoclate in virgin hemophiliacs has confirmed its viral safety. Our laboratories are exploiting a similar strategy of immunoaffinity chromatography to ensure the viral safety of FIX and protein C preparations derived from plasma.

The structure of the hexameric atrazine chlorohydrolase AtzA

The structure of atrazine chlorohydrolase (AtzA) is presented and is used to reinterpret data from genetic, biochemical and evolutionary studies, providing insight into why this recently evolved enzyme appears to be poorly adapted for its physiological substrate compared with the alternative metal-dependent atrazine dechlorinase TrzN.

Atrazine chlorohydrolase (AtzA) was discovered and purified in the early 1990s from soil that had been exposed to the widely used herbicide atrazine. It was subsequently found that this enzyme catalyzes the first and necessary step in the breakdown of atrazine by the soil organism Pseudomonas sp. strain ADP. Although it has taken 20 years, a crystal structure of the full hexameric form of AtzA has now been obtained. AtzA is less well adapted to its physiological role (i.e. atrazine dechlorination) than the alternative metal-dependent atrazine chlorohydrolase (TrzN), with a substrate-binding pocket that is under considerable strain and for which the substrate is a poor fit.