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Introduction Repetitive exposure to blast overpressure waves can be a part of routine military and law enforcement training. However, our understanding of the effects of that repetitive exposure on human neurophysiology remains limited. To link an individual's cumulative exposure with their neurophysiological effects, overpressure dosimetry needs to be concurrently collected with relevant physiological signals. Eye tracking has shown promise for providing insight into neurophysiological change because of neural injury, but video-based technology limits usage to a laboratory or clinic. In the present work, we show capability for using electrooculography-based eye tracking to enable physiological assessment in the field during activities involved repetitive blast exposures. Materials and Methods Overpressure dosimetry was accomplished by using a body-worn measurement system that captures continuous sound pressure levels as well as pressure waveforms of blast event in the range of 135-185 dB peak (0.1-36 kPa). Electrooculography eye tracking was performed using a commercial Shimmer Sensing system, which captured horizontal eye movements of both the left and right eyes, as well as vertical eye movements of the right eye, from which blinks can also be extracted. Data were collected during breaching activities that included repetitive use of explosives. Participants in the study were U.S. Army Special Operators and Federal Bureau of Investigations special agents. Approval for research was received by the Massachucetts Institute of Technology Committee on the Use of Humans as Experimental Subjects, the Air Force Human Research Protections Office, and the Federal Bureau of Investigations Institutional Review Board. Results The energy from overpressure events was accumulated and summarized into an 8-hour equivalent of sound pressure level (i.e. LZeq8hr). The total exposure in a single day, i.e. the LZeq8hr, ranged from 110 to 160 dB. Oculomotor features, such as blink and saccade rate, as well as variance in blink waveforms, show changes across the period of overpressure exposure. However, the features that showed significant change across the population were not necessarily the ones that showed significant correlation with the levels of overpressure exposure. A regression model built to predict overpressure levels from oculomotor features alone showed a significant association (R  = 0.51, P  < .01). Investigation of the model indicates that changes in the saccade rate and blink waveforms are driving the relationship. Conclusions This study successfully demonstrated that eye tracking can be performed during training activities, such as explosive breaching, and that the modality may provide insight into neurophysiological change across periods of overpressure exposure. The results presented herein show that electrooculography-based eye tracking may be a useful method of assessing individualized physiological effects of overpressure exposure in the field. Future work is focused on time-dependent modeling to assess continuous changes in eye movements as this will enable building dose–response curves. [ABSTRACT FROM AUTHOR]

Background: Use of acid‐suppressive medications (ASMs), for example, proton pump inhibitors (PPIs) and histamine‐2 receptor antagonists (H2RAs), has been rising along with the incidence of pediatric immune‐mediated diseases (IMDs). We conducted a scoping review to characterize the literature about prenatal or pediatric exposure to ASMs in relation to incident pediatric IMDs. Methods: Electronic searches were conducted to identify studies from 2001 to 2023 on (a) prenatal or pediatric exposure to PPIs and/or H2RAs and (b) the risk of developing chronic IMDs during childhood. Eligible studies after title/abstract and full‐text screening underwent data abstraction. Results: Of 26 eligible studies, 11 focused on prenatal ASM exposure and 16 on pediatric exposure. Asthma was the most commonly investigated outcome (16 studies), followed by other allergic diseases (8), eosinophilic esophagitis (3), inflammatory bowel disease (2), and other autoimmune diseases (2). Positive associations between ASM exposure and pediatric IMD outcomes emerged in all but two recent studies, which reported null or negative associations with allergic diseases. The strength of associations was similar across exposure times (prenatal/pediatric), medications (PPIs/H2RAs), and outcomes. Dose–response relationships were often present (7/11 studies). Reported effects by trimester and age of exposure varied. Commonly reported limitations were residual confounding, exposure misclassification, and outcome misclassification. Conclusion: In summary, prenatal or pediatric exposure to PPIs and/or H2RAs has frequently, but not exclusively, been associated with the development of asthma, other allergic diseases, and chronic gastrointestinal IMDs. However, concerns remain about confounding and other sources of bias. Prescribers and families should be aware of these possible risks of ASMs. [ABSTRACT FROM AUTHOR]

Active components of psychological intervention for RAP remain unclear. This study involved completing interviews about parental experience of psychological intervention for RAP to ascertain how and why psychological intervention can be effective. Difficulty making sense of RAP and barriers to treatment were identified as struggles. Acceptance and containment were key overlapping mechanisms, which allowed families to develop a changed relationship with the pain and manage the impact of pain. To further develop interventions, the role of containment should be considered and acceptance-based interventions explored, given the growing evidence base in this area. Practical implications of this research are also discussed. [ABSTRACT FROM AUTHOR]

Microgravity and elevated levels of CO2 are two common environmental stressors in spaceflight that may affect cognitive performance of astronauts. In this randomized, double-blind, crossover trial (SPACECOT), 6 healthy males (mean ± SD age: 41 ± 5 yr) were exposed to 0.04% (ambient air) and 0.5% CO2 concentrations during 26.5-h periods of 12° head-down tilt (HDT) bed rest with a 1-wk washout period between exposures. Subjects performed the 10 tests of the Cognition Test Battery before and on average 0.1, 5.2, and 21.0 h after the initiation of HDT bed rest. HDT in ambient air induced a change in response strategy, with increased response speed (+0.19 SD; P = 0.0254) at the expense of accuracy (-0.19 SD; P = 0.2867), resulting in comparable cognitive efficiency. The observed effects were small and statistically significant for cognitive speed only. However, even small declines in accuracy can potentially cause errors during mission-critical tasks in spaceflight. Unexpectedly, exposure to 0.5% CO2 reversed the response strategy changes observed under HDT in ambient air. This was possibly related to hypercapnia-induced cerebrovascular reactivity that favors cortical regions in general and the frontal cortex in particular, or to the CNS arousing properties of mildly to moderately increased CO2 levels. There were no statistically significant time-in-CO2 effects for any cognitive outcome. The small sample size and the small effect sizes are major limitations of this study and its findings. The results should not be generalized beyond the group of investigated subjects until they are confirmed by adequately powered follow-up studies. NEW & NOTEWORTHY Simulating microgravity with exposure to 21 h of 12° head-down tilt bed rest caused a change in response strategy on a range of cognitive tests, with a statistically significant increase in response speed at the expense of accuracy. Cognitive efficiency was not affected. The observed speed-accuracy tradeoff was small but may nevertheless be important for mission-critical tasks in spaceflight. Importantly, the change in response strategy was reversed by increasing CO2 concentrations to 0.5%. [ABSTRACT FROM AUTHOR]

This report documents the first occurrence of the fungus Fusarium merismoides var. chlamydosporale (Tuberculariaceae; Ascomycota) in Mississippi. The presence of this fungus was first observed in a rural area of [...]

BACKGROUND: Neuropsychological changes that may occur due to the environmental and psychological stressors of prolonged spaceflight motivated the development of the Cognition Test Battery. The battery was designed to assess multiple domains of neurocognitive functions linked to specific brain systems.Tests included in Cognition have been validated, but not in high-performing samples comparable to astronauts, which is an essential step toward ensuring their usefulness in long-duration space missions. METHODS: We administered Cognition (on laptop and iPad) and the WinSCAT, counterbalanced for order and version, in a sample of 96 subjects (50% women; ages 25-56 yr) with at least a Master's degree in science, technology, engineering, or mathematics (STEM). We assessed the associations of age, sex, and administration device with neurocognitive performance, and compared the scores on the Cognition battery with those of WinSCAT. Confirmatory factor analysis compared the structure of the iPad and laptop administration methods using Wald tests. RESULTS: Age was associated with longer response times (mean β = 0.12) and less accurate (mean β = -0.12) performance, women had longer response times on psychomotor (β = 0.62), emotion recognition (β = 0.30), and visuo-spatial (β = 0.48) tasks, men outperformed women on matrix reasoning (β = -0.34), and performance on an iPad was generally faster (mean β = -0.55).The WinSCAT appeared heavily loaded with tasks requiring executive control, whereas Cognition assessed a larger variety of neurocognitive domains. DISCUSSION: Overall results supported the interpretation of Cognition scores as measuring their intended constructs in high performing astronaut analog samples. [ABSTRACT FROM AUTHOR]

Non-invasive imaging of gene expression can be used to track implanted cells in vivo but often requires the addition of an exogenous contrast agent that may have limited tissue access. We show that the urea transporter (UT-B) can be used as a gene reporter, where reporter expression is detected using 1H MRI measurements of UT-B-mediated increases in plasma membrane water exchange. HEK cells transfected with the reporter showed an increased apparent water exchange rate (AXR), which increased in line with UT-B expression. AXR values measured in vivo, in UT-B-expressing HEK cell xenografts, were significantly higher (about twofold, P < 0.0001), compared with non-expressing controls. Fluorescence imaging of a red fluorescent protein (mStrawberry), co-expressed with UT-B showed that UT-B expression correlated in a linear fashion with AXR. Transduction of rat brain cells in situ with a lentiviral vector expressing UT-B resulted in about a twofold increase in AXR at the site of virus injection. [ABSTRACT FROM AUTHOR]

Glycosylation is a ubiquitous post-translational modification, present in over 50 % of the proteins in the human genome, with important roles in cell-cell communication and migration. Interest in glycome profiling has increased with the realization that glycans can be used as biomarkers of many diseases, including cancer. We report here the first tomographic imaging of glycosylated tissues in live mice by using metabolic labeling and a gadolinium-based bioorthogonal MRI probe. Significant N-azidoacetylgalactosamine dependent T1 contrast was observed in vivo two hours after probe administration. Tumor, kidney, and liver showed significant contrast, and several other tissues, including the pancreas, spleen, heart, and intestines, showed a very high contrast (>10-fold). This approach has the potential to enable the rapid and non-invasive magnetic resonance imaging of glycosylated tissues in vivo in preclinical models of disease. [ABSTRACT FROM AUTHOR]

Purpose To assess the potential of a gene reporter system, based on a urea transporter (UTB) and hyperpolarized [13C]urea. Methods Mice were implanted subcutaneously with either unmodified control cells or otherwise identical cells expressing UTB. After injection of hyperpolarized [13C]urea, a spin echo sequence was used to measure urea concentration, T1, and diffusion in control and UTB-expressing tissue. Results The apparent diffusion coefficient of hyperpolarized urea was 21% lower in tissue expressing UTB, in comparison with control tissue ( P < 0.05, 1-tailed t-test, n = 6 in each group). No difference in water apparent diffusion coefficient or cellularity between these tissues was found, indicating that they were otherwise similar in composition. Conclusion Expression of UTB, by mediating cell uptake of urea, lowers the apparent diffusion coefficient of hyperpolarized 13C urea in tissue and thus the transporter has the potential to be used as a magnetic resonance-based gene reporter in vivo. Magn Reson Med 73:1401-1406, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

As my term as President of the Mississippi Academy of Sciences draws to a close, I would like to thank the Members of the Academy and the Board of Directors [...]

I am honored to serve as your President during the 2004-2005 academic year, the 75th anniversary of the Mississippi Academy of Sciences. The Academy has a rich history of supporting [...]

Dr. Johnnie-Marie Whitfield, beloved Millsaps professor and Membership Director of the Mississippi Academy of Sciences, died January 13, 2002. Dr. Whitfield leaves a legacy of dedication to science and science [...]

Purpose: The purpose of this study was to quantify the relationship of bone marrow response to radiation dose, using 3’-deoxy-3’-[18F]fluorothymidine ([18F]FLT)-labeled uptake quantified in positron-emission tomography (PET) scans. Methods and Materials: Pre- and post-Week 1 treatment [18F]FLT PET images were registered to the CT images used to create the radiation treatment plan. Changes in [18F]FLT uptake values were measured using profile data of standardized uptake values (SUVs) and doses along the vertebral bodies located at a field border where a range of radiation doses were present for 10 patients. Data from the profile measurements were grouped into 1 Gy dose bins from 1 to 9 Gy to compare SUV changes for all patients. Additionally, the maximum pretreatment, the post-Week 1 treatment, and the dose values located within the C6–T7 vertebrae that straddled the field edge were measured for all patients. Results: Both the profile and the individual vertebral data showed a strong correlation between SUV change and radiation dose. Relative differences in SUVs between bins >1 Gy and <7 Gy were statistically significant (p < 0.01, two-sample t test). The reduction in SUV was approximately linear until it reached a reduction threshold of 75%–80% in SUV for doses greater than 6 Gy/week for both the dose-binned data and the vertebral maximum SUVs. Conclusions: The change in SUV observed in head and neck cancer patients treated with chemoradiation shows the potential for using [18F]FLT PET images for identifying active bone marrow and monitoring changes due to radiation dose. Additionally, the change in [18F]FLT uptake observed in bone marrow for different weekly doses suggests potential dose thresholds for reducing bone marrow toxicity. [ABSTRACT FROM AUTHOR]

Background: Mitochondria contribute to the dynamics of cellular metabolism, the production of reactive oxygen species, and apoptotic pathways. Consequently, mitochondrial function has been hypothesized to influence functional decline and vulnerability to disease in later life. Mitochondrial genetic variation may contribute to altered susceptibility to the frailty syndrome in older adults. Methodology/Principal Findings: To assess potential mitochondrial genetic contributions to the likelihood of frailty, mitochondrial DNA (mtDNA) variation was compared in frail and non-frail older adults. Associations of selected SNPs with a muscle strength phenotype were also explored. Participants were selected from the Cardiovascular Health Study (CHS), a population-based observational study (1989-1990, 1992-1993). At baseline, frailty was identified as the presence of three or more of five indicators (weakness, slowness, shrinking, low physical activity, and exhaustion). mtDNA variation was assessed in a pilot study, including 315 individuals selected as extremes of the frailty phenotype, using an oligonucleotide sequencing microarray based on the Revised Cambridge Reference Sequence. Three mtDNA SNPs were statistically significantly associated with frailty across all pilot participants or in sex-stratified comparisons: mt146, mt204, and mt228. In addition to pilot participants, 4,459 additional men and women with frailty classifications, and an overlapping subset of 4,453 individuals with grip strength measurements, were included in the study population genotyped at mt204 and mt228. In the study population, the mt204 C allele was associated with greater likelihood of frailty (adjusted odds ratio = 2.04, 95% CI = 1.07-3.60, p = 0.020) and lower grip strength (adjusted coefficient =-2.04, 95% CI =-3.33- -0.74, p = 0.002). Conclusions: This study supports a role for mitochondrial genetic variation in the frailty syndrome and later life muscle strength, demonstrating the importance of the mitochondrial genome in complex geriatric phenotypes. [ABSTRACT FROM AUTHOR]

Purpose: Single photon emission computed tomography (SPECT) provides a map of the spatial distribution of lung perfusion. Thus, SPECT guidance can be used to divert dose away from higher-functioning lung, potentially reducing lung toxicity. We present a methodology for achieving this aim and test it in intensity-modulated radiotherapy (IMRT) treatment-planning. Methods and Materials: IMRT treatment plans were generated with and without SPECT guidance and compared for 5 patients. Healthy lung was segmented into four regions on the basis of SPECT intensity in the SPECT plan. Dose was sequentially allowed to the target via regions of increasing SPECT intensity. This process results in reduction of dose to functional lung, reflected in the dose–function histogram (DFH). The plans were compared using DFHs and F20/F30 values (Fx is the functional lung receiving dose above x Gy). Results: In all cases, the SPECT-guided plan produced a more favorable DFH compared with the non-SPECT-guided plan. Additionally, the F20 and F30 values were reduced for all patients by an average of 13.6% ± 5.2% and 10.5% ± 5.8%, respectively. In all patients, DFHs of the two highest-functioning SPECT regions were reduced, whereas DFHs of the two lower-functioning regions were increased, illustrating the dose “give-take” between SPECT regions during redistribution. Conclusions: SPECT-guided IMRT shows potential for reducing the dose delivered to highly functional lung regions. This dose reduction could reduce the number of high-grade pneumonitis cases that develop after radiation treatment and improve patient quality of life. [Copyright &y& Elsevier]

The mechanisms used by fungal cells to repair DNA damage have been subjects of intensive investigation for almost 50 years. As a result, the model yeasts Schizosaccharomyces pombe and Saccharomyces cerevisiae have led the way in yielding critical insights into the nature of the DNA damage response. At the same time, largely through the efforts of Etta Kafer, Hirokazu Inoue, and colleagues, a substantial collection of Aspergillus nidulans and Neurospora crassa DNA repair mutants has been identified and characterized in detail. As the analysis of these mutants continues and increasing amounts of annotated genome sequence become available, it is becoming readily apparent that the DNA damage response of filamentous fungi possesses several features that distinguish it from the model yeasts. These features are emphasized in this review, which describes the genes, regulatory networks, and processes that compose the fungal DNA damage response. Further characterization of this response will likely yield general insights that are applicable to animals and plants. Moreover, it may also become evident that theDNA damage response can be manipulated to control fungal growth. [Copyright &y& Elsevier]

Presents a study which developed a technique to quantify the distribution volume of color molecules in intratumoral infusion. Methodology; Results; Discussion.

Examines the effect of Aspergillus nidulans protein kinase mutation extragenic suppressors on nuclear division, septation and conidiation. Role of kinases in mitotic promotion; Problem in cell polarity maintenance; Identification of genes regulating protein kinase activity; Occurrence of septation and nuclear division changes in conidiophore development.

Focuses on the use of fungi to study genetics. Mitosis and meiosis; Demonstration of Mendel's law; Concepts of crossing-over, genetic linkage and mapping.