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Biofilms are microbial communities that represent a highly abundant form of microbial life on Earth. Inside biofilms, phenotypic and genotypic variations occur in three-dimensional space and time; microscopy and quantitative image analysis are therefore crucial for elucidating their functions. Here, we present BiofilmQ-a comprehensive image cytometry software tool for the automated and high-throughput quantification, analysis and visualization of numerous biofilm-internal and whole-biofilm properties in three-dimensional space and time.

ObjectiveCan oculomotor, vestibular, reaction time and cognitive eye-tracking tests (OVRT-C) assess mild traumatic brain injury?BackgroundOVRT-C tests using eye tracking technology have been employed in our previous studies for assessing mild traumatic brain injury (mTBI). Here we present a composite Concussion Assessment algorithm that incorporates these findings.Design/MethodsConcussion Assessment algorithm was based on a data analysis from 406 males and females 18–45 years old. The subjects included 106 patients diagnosed with mTBI and 300 healthy controls. Diagnosis of mTBI was made using accepted medical practice. The participants were tested with a battery of OVRT-C tests delivered on the I-Portal Neuro Otologic Test Center (Dx NOTC) device (Neurolign Technology). A logistic regression model was used to derive the algorithm using a random sample of 70% of the data-set and validated on the remaining 30% of the data-set. Device test-retest reliability and inter-rater variability were assessed in a separate study in healthy control volunteers, ages 19–43 (n = 30). Subjects were tested with OVRT-C tests using the Dx100 which is equivalent to the NOTC. Test-retest reliability was assessed using Intraclass Correlation Coefficient (ICC) and Cronbach's alpha; testers and devices influence were assessed using a random effect regression model.ResultsTest-retest reliability of OVRT-C tests using eye tracking technology was acceptable (ICC >0.6 for all variables). The Concussion assessment algorithm was based on six OVRT-C tests. In the validation data Concussion Assessment algorithm was able to separate concussed versus controls with a sensitivity of 78.6% and specificity of 72.3%.ConclusionsOVRT-C tests delivered on I-Portal devices are repeatable and reliable. The assessment can identify mTBI subjects within an acute time post-injury with high sensitivity and specificity. The results support the use of this eye tracking device as well as the assessment to aid in the diagnosis of mTBI for patients 18–45 year old.

Background Mild traumatic brain injury (TBI) is a common public health issue that may contribute to chronic degenerative disorders. Membrane lipids play a key role in tissue responses to injury, both as cell signals and as components of membrane structure and cell signaling. This study demonstrates the ability of high resolution mass spectrometry imaging (MSI) to assess sequences of responses of lipid species in a rat controlled cortical impact model for concussion. New method A matrix of implanted silver nanoparticles was implanted superficially in brain sections for matrix-assisted laser desorption (MALDI) imaging of 50 μm diameter microdomains across unfixed cryostat sections of rat brain. Ion-mobility time-of-flight MS was used to analyze and map changes over time in brain lipid composition in a rats after Controlled Cortical Impact (CCI) TBI. Results Brain MS images showed changes in sphingolipids near the CCI site, including increased ceramides and decreased sphingomyelins, accompanied by changes in glycerophospholipids and cholesterol derivatives. The kinetics differed for each lipid class; for example ceramides increased as early as 1 day after the injury whereas other lipids changes occurred between 3 and 7 days post injury. Comparison with existing method(s) Silver nanoparticles MALDI matrix is a sensitive new tool for revealing previously undetectable cellular injury response and remodeling in neural, glial and vascular structure of the brain. Conclusions Lipid biochemical and structural changes after TBI could help highlighting molecules that can be used to determine the severity of such injuries as well as to evaluate the efficacy of potential treatments.

Background Traumatic brain injury is an increasingly prevalent injury seen in both civilian and military populations. Regardless of the mechanisms of injury, the most common sub-type of injury continues to be mild traumatic brain injury. Within the last decade, there has been tremendous growth in the literature regarding this disease entity. Purpose To describe the obstacles necessary to overcome in performing a rigorous and sound clinical research study investigating mild traumatic brain injury. This examination begins by a consideration of changing standards for good faith open and total reporting of any and all conflicts of interest or commitment. This issue is particularly critical in mTBI research. We next examine obstacles that include but are not limited to diagnostic criteria, inclusion/exclusion criteria, source of injury, previous history of injury, presence of comorbid conditions and proper informed consent of participants. Frequently, multi-center studies are necessary for adequate subject accrual with the added challenges of site coordination, data core management and site specific study conduct. We propose a total reversal to the traditional translational research approach where clinical studies drive new concepts for future basic science studies. Conclusions There have been few mild traumatic brain injury clinical trials in the literature with treatments/interventions that have been able to overcome many of these described obstacles. We look forward to the results of current and ongoing clinical mild traumatic brain injury studies providing the tools necessary for the next generation of basic science projects.

Alcohol abuse is a chronic disease characterized by the consumption of alcohol at a level that interferes with physical and mental health and causes serious and persistent changes in the brain. Lipid metabolism is of particular interest due to its high concentration in the brain. Lipids are the main component of cell membranes, are involved in cell signaling, signal transduction, and energy storage. In this study, we analyzed lipid composition of chronically ethanol exposed mouse brains. Juvenile (JUV) and adult (ADU) mice were placed on a daily limited-access ethanol intake model for 52 days. After euthanasia, brains were harvested, and total lipids were extracted from brain homogenates. Samples were analyzed using high resolution mass spectrometry and processed by multivariate and univariate statistical analysis. Significant lipid changes were observed in different classes including sphingolipids, fatty acids, lysophosphatidylcholines, and other glycerophospholipids.

Objective: Patients with peripheral vestibular dysfunction because of gravitational receptor asymmetries display signs of cognitive dysfunction and are assumed to have neurobehavioral sequelae. This was tested with pre- and postoperatively quantitative measurements in three cohort groups with superior semicircular canal dehiscence syndrome (SSCDS) symptoms with: 1) superior canal dehiscence (SCD) repaired via a middle cranial fossa craniotomy and canal plugging only; 2) otic capsule defects not visualized with imaging (no-iOCD) repaired with round window reinforcement (RWR) only; or 3) both SCD plugging and subsequent development of no-iOCD followed by RWR. Study Design: Prospective patient series. Setting: Tertiary referral center. Patients: There were 13 adult and 4 pediatric patients with SSCDS who had completion of neuropsychology test batteries pre- and every 3 months postoperatively. Eight patients had no-iOCD and RWR exclusively, 5 had SCD and plugging exclusively, and 4 had both SCD plugging and then development of no-iOCD with RWR. These cohorts included SSCDS with 2 different dehiscence locations. Interventions: Completion of a neuropsychology test battery preoperatively and at 3, 6, 9, and 12 months postoperatively that included: Beck Depression Inventory-II (BDI); Wide Range Intelligence Test (WRIT FSIQ) including average verbal (crystallized intelligence) and visual (fluid intelligence); Wide Range Assessment of Memory and Learning (WRAML), including the four domains of verbal memory, visual memory, attention/concentration, and working memory; and Delis–Kaplan Executive Function System (D-KEFS). The Dizziness Handicap Inventory (DHI) and the Headache Impact Test (HIT-6) were also completed to assess the impact of their disease on activities pre- and postoperatively. Main Outcome Measures: Quantitative and statistical analysis of their cognitive and neurobehavioral function. Results: The pattern of differences between the SCD group and the no-iOCD group from WRAML verbal, visual, and attention test performance indicate different postoperative clinical trajectories. For the WRAML, there was a statistically significant improvement for visual memory and verbal memory for the no-iOCD only and both (SCD and subsequent no-iOCD) groups, but no mean improvement for the SCD only group. By contrast, the no-iOCD group had significantly lower scores on the WRAML attention test preoperatively, but they recovered postoperatively to match the other groups. The preoperative findings and postoperative outcomes did not differ significantly among patient groups on the WRAML working memory test, D-KEFS motor scores, D-KEFS number and letter scores, or Wide Range Intelligence Test scores. There was a significant decrease in the BDI for all groups. The IQ scores were unchanged. There was a statistically significant improvement in the DHI and HIT-6 scores postoperatively in all groups. Conclusions: There was a marked overall improvement in cognitive and neurobehavioral function postoperatively. Variability may result from duration of underlying disease before intervention. The initial decrement or delay in performance improvement measured in several patients may represent brain reorganization. Greater longitudinal data and greater subject numbers are necessary to better understand and optimize cognitive recovery.

We describe the selection of reduced chlorhexidine susceptibility during chlorhexidine use in a patient with two episodes of cutaneous USA300 methicillin-resistant Staphylococcus aureus abscess. The second clinical isolate harbors a novel plasmid that encodes the QacA efflux pump. Greater use of chlorhexidine for disease prevention warrants surveillance for resistance.

Microorganisms navigate and divide on surfaces to form multicellular structures called biofilms, the most widespread survival strategy found in the bacterial world. One common assumption is that cellular components guide the spatial architecture and arrangement of multiple species in a biofilm. However, bacteria must contend with mechanical forces generated through contact with surfaces and under fluid flow, whose contributions to colonization patterns are poorly understood. Here, we show how the balance between motility and flow promotes the emergence of morphological patterns in Caulobacter crescentus biofilms. By modeling transport of single cells by flow and Brownian-like swimming, we show that the emergence of these patterns is guided by an effective Péclet number. By analogy with transport phenomena we show that, counter-intuitively, fluid flow represses mixing of distinct clonal lineages, thereby affecting the interaction landscapes between biofilm-dwelling bacteria. This demonstrates that hydrodynamics influence species interaction and evolution within surface-associated communities., In the wild, bacteria grow into structures called biofilms. Here the authors demonstrate that their spatial organization and heterogeneity depends on the interplay between fluid flow and single cell motility; this highlights the role of hydrodynamics in biofilm formation.