Publications by authors named "Barry Katz"
Article Synopsis
- The article outlines the second phase of the CARE Consortium study, which investigates the neuropsychiatric effects of concussions and repeated head impacts on collegiate athletes and military cadets.
- Participants were evaluated at three stages: undergraduate baseline, exit from school or academy, and up to 6 years post-graduation, using online brain health assessments.
- While there were some statistical differences in participant characteristics over time, the overall findings indicate that exit and postgrad groups largely resemble the baseline group, allowing for valuable insights into the long-term impacts of head injuries.
Article Synopsis
- Chancroid, a genital ulcer disease causing painful skin ulcers, is linked to a bacterium that uses a specific receptor, HgbA, to acquire heme from hosts, crucial for its disease progression.
- The study involved creating a mutant strain (35000HPΔΔ) that showed growth issues when using human hemoglobin for iron; however, trials with human volunteers showed both the mutant and the parent strain produced similar skin reactions, indicating that the YfeABCD transporter isn't essential for the bacteria's virulence.
- The research suggests that despite the deletion of the YfeABCD system, the bacteria can rely on alternative transport systems like HbpA and others to manage heme transport, highlighting the redundancy of vir
To assess the effectiveness of 38 percent silver diamine fluoride (SDF) in arresting cavitated caries lesions in young U.S. children.
View Article and Find Full Text PDFArticle Synopsis
- A pathogen causes skin ulcers in tropical children and chancroid in sexually active adults, utilizing anaerobic respiration and mixed acid fermentation to generate energy in these environments.
- The study investigated the role of specific genes related to formate production and transport in a specific strain of bacteria during human infection, creating single and double mutants to explore their effects on growth and virulence.
- Results showed that while formate production is present, the lack of certain genes did not significantly affect the ability of the bacteria to cause disease, indicating that these genes are not essential for virulence in humans.
Background And Objectives: Some athletes experience a slow recovery after sport-related concussion (SRC). There is little agreement on what constitutes slow recovery, however, and minimal data on the prevalence, predictors, or prognosis for this group. The objectives of this study were to apply an operationalized definition of slow recovery and characterize predictors and long-term prognosis of these individuals.
View Article and Find Full Text PDFCompared with wounded skin, ascorbic acid is enriched in pustules of humans experimentally infected with Haemophilus ducreyi. Compared with the broth-grown inocula, transcription of the H. ducreyi ulaABCD operon, which encodes genes for ascorbic acid uptake, is increased in pustules.
View Article and Find Full Text PDFThe hematopoietic system is highly sensitive to stress from both aging and radiation exposure, and the hematopoietic acute radiation syndrome (H-ARS) should be modeled in the geriatric context separately from young for development of age-appropriate medical countermeasures (MCMs). Here we developed aging murine H-ARS models, defining radiation dose response relationships (DRRs) in 12-month-old middle-aged and 24-month-old geriatric male and female C57BL/6J mice, and characterized diverse factors affecting geriatric MCM testing. Groups of approximately 20 mice were exposed to ∼10 different doses of radiation to establish radiation DRRs for estimation of the LD50/30.
View Article and Find Full Text PDFCpxRA is an envelope stress response system that is highly conserved in the . CpxA has kinase activity for CpxR and phosphatase activity for phospho-CpxR (CpxR-P), a transcription factor. In response to membrane stress, CpxR-P is produced and upregulates genes involved in membrane repair and downregulates genes that encode virulence factors that are trafficked across the cell membrane.
View Article and Find Full Text PDFThe purpose of this study was to assess the relationship between the number of teeth present at 12 months and decayed, missing, or filled surfaces (dmfs) at 30 and 48 months. Data are from a longitudinal, multisite study with clinical dental examinations conducted at 12, 30, and 48 months of age. Spearman correlation and chi-square tests assessed relationships between teeth present at 12 months and dmfs at 30 (n equals 1,062) and 48 months (n equals 985).
View Article and Find Full Text PDFBackground: Sport-related concussion is recognized as a significant injury with variable recovery rates.
Objective: This study defined the acute natural history of sport concussion in male and female collegiate athletes participating in a broad array of sports.
Methods: We conducted a prospective, longitudinal investigation among collegiate student athletes (n = 34,709) from 30 academic institutions.
Importance: Validation of protein biomarkers for concussion diagnosis and management in military combative training is important, as these injuries occur outside of traditional health care settings and are generally difficult to diagnose.
Objective: To investigate acute blood protein levels in military cadets after combative training-associated concussions.
Design, Setting, And Participants: This multicenter prospective case-control study was part of a larger cohort study conducted by the National Collegiate Athletic Association and the US Department of Defense Concussion Assessment Research and Education (CARE) Consortium from February 20, 2015, to May 31, 2018.
Medical countermeasures (MCMs) for hematopoietic acute radiation syndrome (H-ARS) should be evaluated in well-characterized animal models, with consideration of at-risk populations such as pediatrics. We have developed pediatric mouse models of H-ARS and delayed effects of acute radiation exposure (DEARE) for efficacy testing of MCMs against radiation. Male and female C57BL/6J mice aged 3, 4, 5, 6, 7 and 8 weeks old (±1 day) were characterized for baseline hematopoietic and gastrointestinal parameters, radiation response, efficacy of a known MCM, and DEARE at six and 12 months after total-body irradiation (TBI).
View Article and Find Full Text PDFThe accuracy of microbial community detection in 16S rRNA marker-gene and metagenomic studies suffers from contamination and sequencing errors that lead to either falsely identifying microbial taxa that were not in the sample or misclassifying the taxa of DNA fragment reads. Removing contaminants and filtering rare features are two common approaches to deal with this problem. While contaminant detection methods use auxiliary sequencing process information to identify known contaminants, filtering methods remove taxa that are present in a small number of samples and have small counts in the samples where they are observed.
View Article and Find Full Text PDFExudative cutaneous ulcers (CU) in yaws-endemic areas are associated with subsp. (TP) and (HD), but one-third of CU cases are idiopathic (IU). Using mass drug administration (MDA) of azithromycin, a yaws eradication campaign on Lihir Island in Papua New Guinea reduced but failed to eradicate yaws; IU rates remained constant throughout the campaign.
View Article and Find Full Text PDFObjectives: To examine sex differences in sport-related concussion (SRC) across comparable sports.
Methods: Prospective cohort of collegiate athletes enrolled between 2014 and 2017 in the Concussion Assessment, Research and Education Consortium study.
Results: Among 1071 concussions (females=615; 57.
Development of medical countermeasures against radiation relies on robust animal models for efficacy testing. Mouse models have advantages over larger species due to economics, ease of conducting aging studies, existence of historical databases, and research tools allowing for sophisticated mechanistic studies. However, the radiation dose-response relationship of inbred strains is inherently steep and sensitive to experimental variables, and inbred models have been criticized for lacking genetic diversity.
View Article and Find Full Text PDFImportance: There is potential scientific and clinical value in validation of objective biomarkers for sport-related concussion (SRC).
Objective: To investigate the association of acute-phase blood biomarker levels with SRC in collegiate athletes.
Design, Setting, And Participants: This multicenter, prospective, case-control study was conducted by the National Collegiate Athletic Association (NCAA) and the US Department of Defense Concussion Assessment, Research, and Education (CARE) Consortium from February 20, 2015, to May 31, 2018, at 6 CARE Advanced Research Core sites.
Objectives: (CT) and (MG) cause the majority of non-gonococcal urethritis (NGU). The role of (UU) in NGU is unclear. Prior case-control studies that examined the association of UU and NGU may have been confounded by mixed infections and less stringent criteria for controls.
View Article and Find Full Text PDFBackground: Numerous medical organizations recommend a multifaceted approach to the assessment of concussion occurring during sporting events. A number of tools are available to clinicians, with a wide breadth of sensitivity and specificity; however, little work has been done to evaluate the combined efficiency of these tools in concussed male and female athletes from a broad array of collegiate sports and with variable time from the pre-season baseline evaluation.
Objective: The aim of this study was to optimize the concussion assessment battery for application within the first 72 h of injury, and to identify the necessary baseline retesting frequency.
Article Synopsis
- - The study investigates the virulence of two strains of *Haemophilus ducreyi*, specifically comparing a class I strain (35000HP) and a derivative class II strain (FX548) to assess their potential for vaccine testing against chancroid and cutaneous ulcers in children.
- - Results showed that the rate of papule formation was significantly higher for 35000HP compared to FX548 (95.8% vs. 62.5%), indicating that FX548 is less virulent in humans.
- - Despite both strains expressing similar amounts of the hemoglobin receptor (HgbA) and showing comparable growth patterns, FX548's reduced pathogenicity suggests it may not be suitable for evaluating the efficacy of H
Objective: We compared data from the National Collegiate Athletic Association (NCAA) Concussion Study (1999-2001) and the NCAA-Department of Defense Concussion Assessment, Research and Education (CARE) Consortium (2014-2017) to examine how clinical management, return to play (RTP) and risk of repeat concussion in collegiate football players have changed over the past 15 years.
Methods: We analysed data on reported duration of symptoms, symptom-free waiting period (SFWP), RTP and occurrence of within-season repeat concussion in collegiate football players with diagnosed concussion from the NCAA Study (n=184) and CARE (n=701).
Results: CARE athletes had significantly longer symptom duration (CARE median=5.