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Genome degradation correlates with host adaptation and systemic disease in Salmonella. Most lineages of the S. enterica subspecies Typhimurium cause gastroenteritis in humans; however, the recently emerged ST313 lineage II pathovar commonly causes systemic bacteremia in sub-Saharan Africa. ST313 lineage II displays genome degradation compared to gastroenteritis-associated lineages; yet, the mechanisms and causal genetic differences mediating these infection phenotypes are largely unknown. We find that the ST313 isolate D23580 hyperdisseminates from the gut to systemic sites, such as the mesenteric lymph nodes (MLNs), via CD11b+ migratory dendritic cells (DCs). This hyperdissemination was facilitated by the loss of sseI, which encodes an effector that inhibits DC migration in gastroenteritis-associated isolates. Expressing functional SseI in D23580 reduced the number of infected migratory DCs and bacteria in the MLN. Our study reveals a mechanism linking pseudogenization of effectors with the evolution of niche adaptation in a bacterial pathogen.

Background and Aims This study aimed to identify microbial drivers of inflammatory bowel disease [IBD], by investigating mucosal-associated bacteria and their detrimental products in IBD patients. Methods We directly cultured bacterial communities from mucosal biopsies from paediatric gastrointestinal patients and examined for pathogenicity-associated traits. Upon identifying Clostridium perfringens as toxigenic bacteria present in mucosal biopsies, we isolated strains and further characterized toxicity and prevalence. Results Mucosal biopsy microbial composition differed from corresponding stool samples. C. perfringens was present in eight of nine patients' mucosal biopsies, correlating with haemolytic activity, but was not present in all corresponding stool samples. Large IBD datasets showed higher C. perfringens prevalence in stool samples of IBD adults [18.7–27.1%] versus healthy controls [5.1%]. In vitro , C. perfringens supernatants were toxic to cell types beneath the intestinal epithelial barrier, including endothelial cells, neuroblasts, and neutrophils, while the impact on epithelial cells was less pronounced, suggesting C. perfringens may be particularly damaging when barrier integrity is compromised. Further characterization using purified toxins and genetic insertion mutants confirmed perfringolysin O [PFO] toxin was sufficient for toxicity. Toxin RNA signatures were found in the original patient biopsies by PCR, suggesting intestinal production. C. perfringens supernatants also induced activation of neuroblast and dorsal root ganglion neurons in vitro , suggesting C. perfringens in inflamed mucosal tissue may directly contribute to abdominal pain, a frequent IBD symptom. Conclusions Gastrointestinal carriage of certain toxigenic C. perfringens may have an important pathogenic impact on IBD patients. These findings support routine monitoring of C. perfringens and PFO toxins and potential treatment in patients. [ABSTRACT FROM AUTHOR]

Objective: To compare intraocular pressure (IOP) measurements in dogs taken with the Reichert® Tono‐Vera® Vet rebound tonometer with and without the automatic positioning system. Animals Studied: Measurements were taken on 49 eyes from 26 Beagle‐derived dogs with variable genetics—four non‐glaucomatous and 22 ADAMTS10‐mutant dogs affected with different stages of open‐angle glaucoma. Seventeen of the 26 dogs were measured 2–4 times on different days with variable intervals since IOP‐lowering medications were administered. Procedures: In each dog, tonometry was performed with the Tono‐Vera® Vet using three different methods in a randomized order: (Method 1) Average of three readings with an automatic positioning system; (Method 2) one reading with an automatic positioning system; and (Method 3) average of three readings obtained without the automatic positioning system. Statistical analyses included one‐way ANOVA, Tukey pairwise comparisons, and Bland–Altman plots (MiniTab®). Results: With each of the three tonometry methods, 116 measurements were taken, resulting in 348 total IOP measurements with a range of 12.8–49.9 mmHg. The means and standard deviations for each method were 25.4 ± 6.9 mmHg (Method 1), 26.0 ± 7.2 mmHg (Method 2), and 26.9 ± 7.7 mmHg (Method 3), with no significant differences (p =.27). Mean IOP variances were also not significantly different between tonometry methods (p =.24 to.78). Conclusions: Because mean IOPs and their standard deviations were not statistically different between the three tonometry methods, we conclude that Tono‐Vera® Vet measurements conducted without the aid of the positioning system still provide reliable results. [ABSTRACT FROM AUTHOR]

Engaging in exercise and appropriate nutritional intake improves mental health by reducing anxiety, depression, and sleep disturbances. However, few researchers have examined energy availability (EA), mental health, and sleep patterns in athletic trainers (ATs). To examine ATs' EA, mental health risk (ie, depression, anxiety), and sleep disturbances by sex (male, female), job status (part time [PT AT], full time [FT AT]), and occupational setting (college or university, high school, or nontraditional). Cross-sectional study. Free living in occupational settings. A total of 47 ATs (male PT ATs = 12, male FT ATs = 12; female PT ATs = 11, female FT ATs = 12) in the southeastern United States. Anthropometric measurements consisted of age, height, weight, and body composition. Energy availability was measured through energy intake and exercise energy expenditure. We used surveys to assess the depression risk, anxiety (state or trait) risk, and sleep quality. Thirty-nine ATs engaged in exercise, and 8 did not exercise. Overall, 61.5% (n = 24/39) reported low EA (LEA); 14.9% (n = 7/47) displayed a risk for depression; 25.5% (n = 12/47) indicated a high risk for state anxiety; 25.5% (n = 12/47) were at high risk for trait anxiety, and 89.4% (n = 42/47) described sleep disturbances. No differences were found by sex and job status for LEA, depression risk, state or trait anxiety, or sleep disturbances. Those ATs not engaged in exercise had a greater risk for depression (risk ratio [RR] = 1.950), state anxiety (RR = 2.438), trait anxiety (RR = 1.625), and sleep disturbances (RR = 1.147), whereas ATs with LEA had an RR of 0.156 for depression, 0.375 for state anxiety, 0.500 for trait anxiety, and 1.146 for sleep disturbances. Although most ATs engaged in exercise, their dietary intake was inadequate, they were at increased risk for depression and anxiety, and they experienced sleep disturbances. Those who did not exercise were at an increased risk for depression and anxiety. Energy availability, mental health, and sleep affect overall quality of life and can affect ATs' ability to provide optimal health care. [ABSTRACT FROM AUTHOR]

Introduction: Numerous anatomic studies of the shoulder have quantified the size, shape, and variability of either the humerus or scapula individually. However, few have attempted to quantify the relationship of the humerus to the scapula to better understand the spatial variation of these bones in both male and female shoulders. Methods: Seventy-four cadaveric shoulder CT scans (37 males and 37 females with statistically equivalent age and BMI) were reconstructed using Mimics® to create 3D models of the humerus and scapula. After 3D reconstruction, each CT bone model was analyzed in Rapidform® to quantify the morphology of the humerus, scapula, and the spatial relationship between the two to better understand the role of gender on the morphological variability of the glenohumeral joint. Results: Spatial glenohumeral relationships of male shoulders were significantly larger than female shoulders in 13 of 16 measurements; morphology of male humeri were significantly larger than female humeri in 17 of 24 measurements, and scapula and glenoid morphology of male shoulders were significantly larger than female scapula and glenoids in 11 of 22 measurements. Discussion: Numerous significant gender differences in spatial relationships and morphology were identified in this anatomic study of the glenohumeral joint. An improved understanding of these observed binomial distributions has utility for shoulder arthroplasty prosthesis design, computer navigation, and may also be useful to the orthopaedic surgeon during surgical preoperative planning. [ABSTRACT FROM AUTHOR]

The usage of and indications for total shoulder arthroplasty have grown in recent years. Certain aspects of these arthroplasty procedures can be very complex, especially in revision and fracture cases, often leading to proximal humerus bone loss. For cases with significant bone loss, there is a need for improved devices with additional options to treat a wider range of deformities while also mitigating existing complications and rates, such as poor distal fixation, inadequate soft tissue reattachment options, and joint instability. To that end, a fatigue and torsional test was conducted on two different devices to assess the ability of each to survive an extreme fatigue and torsional load when assembled in worst-case configurations. Evaluation of the Equinoxe® humeral reconstruction prosthesis demonstrated superior fixation in both the fatigue loading scenario and also the torsional loading scenario as compared to the 8 mm x 215 mm cemented humeral long stem, where each had only 80 mm of cemented fixation. The results of the fatigue test demonstrated that despite the humeral reconstruction prosthesis being subjected to a 960 N force and 45 Nm bending moment (which was significantly more challenging than the 576 N force and 24.2 Nm bending moment subjected to the cemented humeral long stem), the humeral reconstruction prosthesis completed 1 M cycles without fracture or failure. Additionally, the Equinoxe® humeral reconstruction prosthesis was associated with a significantly greater torsional resistance in both the torque to initial slip (29.4 Nm versus 8.2 Nm; p = 0.0002) and also the maximum torque tofailure (44.3 Nm versus 12.1 Nm; p < 0.0001). These significant improvements in fixation are at least partially attributed to the application of a novel distal fixation ring, which is press fit around the diaphysis of the humerus to supplement the cemented fixation of the distal stem. These fatigue and torsional test results paired with several novel features offer the potential for the Equinoxe® humeral reconstruction prosthesis to be an improved treatment option for patients with proximal humeral bone loss, though clinical follow-up is necessary to confirm these positive biomechanical results. [ABSTRACT FROM AUTHOR]

Introduction: Numerous anatomic studies of the shoulder have quantified the size, shape, and variability of either the humerus or scapula individually. However, few have attempted to quantify the relationship of the humerus to the scapula to better understand the spatial variation of these bones in both male and female shoulders., Methods: Seventy-four cadaveric shoulder CT scans (37 males and 37 females with statistically equivalent age and BMI) were reconstructed using Mimics ® to create 3D models of the humerus and scapula. After 3D reconstruction, each CT bone model was analyzed in Rapidform® to quantify the morphology of the humerus, scapula, and the spatial relationship between the two to better understand the role of gender on the morphological variability of the glenohumeral joint., Results: Spatial glenohumeral relationships of male shoulders were significantly larger than female shoulders in 13 of 16 measurements; morphology of male humeri were significantly larger than female humeri in 17 of 24 measurements, and scapula and glenoid morphology of male shoulders were significantly larger than female scapula and glenoids in 11 of 22 measurements., Discussion: Numerous significant gender differences in spatial relationships and morphology were identified in this anatomic study of the glenohumeral joint. An improved understanding of these observed binomial distributions has utility for shoulder arthroplasty prosthesis design, computer navigation, and may also be useful to the orthopaedic surgeon during surgical preoperative planning.