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The impact of invasive species on the recipient ecosystem can be strongly influenced by the presence of associated symbionts. It is therefore important to evaluate the likelihood of co-introduced symbiont establishment, and this requires an understanding of their life history traits. Here, we investigate survival, reproduction and competition in two non-native branchiobdellidan ectosymbionts (Xironogiton victoriensis and Cambarincola aff. okadai) on invasive signal crayfish (Pacifastacus leniusculus). In vivo, X. victoriensis established viable infrapopulations within 10 weeks, whereas C. aff. okadai went extinct within 2 weeks. Both X. victoriensis and C. aff. okadai deposited cocoons in vivo that hatched in 10–27 and 10–11 days, respectively. In vitro, X. victoriensis and C. aff. okadai survived for over 13 and 15 weeks respectively, although both were negatively affected by increased temperature and nitrate, and were absent from kick samples taken in the field. Only C. aff. okadai deposited cocoons in vitro, and this larger species readily predated on X. victoriensis but not vice versa. Both branchiobdellidans possess traits associated with colonisation success, including a relatively fast reproductive rate and extended off-host survival. Given its survival in vivo and known detrimental effect on signal crayfish X. victoriensis is perhaps more likely to influence host invasion dynamics, although its persistence may be affected by the presence of co-occurring symbionts.

Purpose: The elements of impaired swallowing biomechanics are visually assessed and scored by clinicians using a standardized and validated tool for assessing type and severity of physiological impairments using the Modified Barium Swallow Impairment Profile (MBSImP). However, the functional anatomical correlates that underly noted impairments using MBSImP scoring have not been measured. The purpose of this study was to determine whether differences in MBSImP component scores represent differences in underlying swallowing mechanics as measured by computational analysis of swallowing mechanics (CASM) to better define underlying mechanisms of impairment. Method: A retrospective analysis of modified barium swallow studies from physician-referred adult patients with dysphagia was scored using the MBSImP for laryngeal elevation, anterior hyoid excursion, epiglottic movement, pharyngoesophageal segment opening, and tongue base retraction. A canonical variate analysis (CVA) was performed to determine the movement of anatomical landmarks associated with MBSImP component scores using the CASM method. Mahalanobis distances (D) were then used to detect differences among MBSImP scores for each component assessed. Results: CVA showed significant differences (p < 0.0001) in Mahalanobis distance (D > 1) between MBSImP component scores of 0-1, 0-2, 0-3, or 0-4, as applicable, depending on the component. Discriminant function analyses revealed concomitant increase/worsening in MBSImP score with changes in anatomical positioning of structures. Conclusions: Ratings of swallowing impairment and physiology using the MBSImP have distinct biomechanical correlates with anatomical movements of swallowing. These data further demonstrate how swallowing mechanics are highly interrelated. Understanding these linkages between anatomical and physiological movement within impaired swallowing biomechanics is essential in more specific characterization and treatment of dysphagia.

Purpose: The purpose of this study was to extend the assessment of the psychometric properties of the Modified Barium Swallow Impairment Profile (MBSImP). Here, we re-examined structural validity and internal consistency using a large clinical-registry data set and formally examined rater reliability in a smaller data set. Method: This study consists of a retrospective structural validity and internal consistency analysis of MBSImP using a large data set (N = 52,726) drawn from the MBSImP Swallowing Data Registry and a prospective study of the interrater and intrarater reliability of a subset of studies (N = 50) rated by four MBSImP-trained speech-language pathologists. Structural validity was assessed via exploratory factor analysis. Internal consistency was measured using Cronbach's alpha for each of the multicomponent MBSImP domains, namely, the oral and pharyngeal domains. Interrater reliability and intrarater reliability were measured using the intraclass correlation coefficient (ICC). Results: The exploratory factor analysis showed a two-factor solution with factors precisely corresponding to the scale's oral and pharyngeal domains, consistent with findings from the initial study. Component 17, that is, the esophageal domain, did not load onto either factor. Internal consistency was good for both the oral and pharyngeal domains ([alpha][subscript oral] = 0.81, [alpha][subscript pharyngeal] = 0.87). Interrater reliability was found to be good with ICC[subscript interrater] = 0.78 (95% confidence interval [CI; 0.76, 0.80]). Intrarater reliability was good for each rater, ICC[subscript Rater-1] = 0.82 (95% CI [0.77, 0.86]), ICC[subscript Rater-2] = 0.83 (95% CI [0.79, 0.87]), ICC[subscript Rater-3] = 0.87 (95% CI [0.83, 0.90]), and ICC[subscript Rater-4] = 0.87 (95% CI [0.83, 0.90]). Conclusions: This study leverages a large-scale, clinical data set to provide strong, generalizable evidence that the MBSImP assessment method has excellent structural validity and internal consistency. In addition, the results show that MBSImP-trained speech-language pathologists can demonstrate good interrater and intrarater reliability.

Purpose: The utilization of high-resolution pharyngeal manometry (HRPM) in the evaluation of pharyngeal dysphagia has been increasing; however, standardization of its use has lagged behind. Without standardization using normative values, it is difficult for clinicians to adopt this emerging technology into meaningful use. Our goal is to map and compare the published normative values for common HRPM metrics in order to help establish consensus reference values. Method: A systematic review was conducted on prospective and retrospective studies that included HRPM metrics, defined by an international working group consensus, in healthy adult populations. Data on the following variables were extracted when available: contractile integrals of the pharynx (PhCI), velopharynx, mesopharynx, and hypopharynx, as well as the upper esophageal sphincter (UES) integrated relaxation pressure (IRP), relaxation time (RT), maximum admittance, and hypopharyngeal intrabolus pressure. Results: Thirty studies were included. Significant variation existed in the technique and equipment used to perform procedures between the different studies. Lower PhCIs and UES IRPs were seen in younger compared to older individuals. Higher UES RTs were found in individuals in the upright position compared to the supine position and in those using larger boluses sizes or smaller catheters. Conclusions: Due to the wide variety of protocols, catheter configurations, manufacturers, and software used in the existing literature, it is difficult to formulate consensus on HPRM normative values using pooled data. Prospective studies adhering to standardized HRPM protocols for specific catheter configurations and manufacturers with larger cohorts of normal individuals are necessary to establish proper reference values for HRPM metrics. [ABSTRACT FROM AUTHOR]