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The primary purpose of this study was to assess the level of accuracy (bias) and degree of precision for a group of 24 normal subjects attempting to maintain a constant biting force at levels of 100 gm, 500 gm, 1000 gm and 2000 gm for a period of 10 s each. Accuracy is defined as the difference between subjects' actual level of biting force and the target value they were trying to achieve. Precision is the level or range of variability demonstrated by the subjects while attempting to bite with a constant level of force. Subjects' performance relative to accuracy and precision was also compared when using the central incisors vs. the first permanent molars. Assessment of bite force was measured using a specially designed strain gauge scale which permitted subjects to visually monitor when their biting force equalled a preset resistance. Each subject was instructed to bite on the end of a plastic sheathed steel beam with enough force to activate the indicator needle on the voltage meter to its central position and to try to maintain a constant level of biting force (by attempting to keep the indicator needle steady in its central position). No significant (P> 0.05) differences were found in mean accuracy in bite force for gender or specific teeth used in the biting task. However, a significant difference (P< 0.0001) in mean accuracy in bite force was found to exist between the target levels. At the lowest standard force (100 gm) there was a mean group bias of +17 gm while at the highest standard (2000 gm) the mean group bias was -103 gm. Analysis of subjects' precision in biting force revealed significant differences in performance relative to gender (P< 0.0001), teeth (P< 0.01) and target levels (P< 0.0001). [ABSTRACT FROM AUTHOR]

Livia Sura,1,2 Aarthi Madhavan,1,3 Giselle Carnaby,1,4 Michael A Crary1,31Swallowing Research Laboratory; 2Department of Epidemiology, College of Public Health and Health Professions; 3Department of Speech, Language, and Hearing Sciences, College of Public Health and Health Professions; 4Department of Behavioral Sciences and Community Health, College of Public Health and Health Professions, Gainesville, FL, USAAbstract: Dysphagia is a prevalent difficulty among aging adults. Though increasing age facilitates subtle physiologic changes in swallow function, age-related diseases are significant factors in the presence and severity of dysphagia. Among elderly diseases and health complications, stroke and dementia reflect high rates of dysphagia. In both conditions, dysphagia is associated with nutritional deficits and increased risk of pneumonia. Recent efforts have suggested that elderly community dwellers are also at risk for dysphagia and associated deficits in nutritional status and increased pneumonia risk. Swallowing rehabilitation is an effective approach to increase safe oral intake in these populations and recent research has demonstrated extended benefits related to improved nutritional status and reduced pneumonia rates. In this manuscript, we review data describing age related changes in swallowing and discuss the relationship of dysphagia in patients following stroke, those with dementia, and in community dwelling elderly. Subsequently, we review basic approaches to dysphagia intervention including both compensatory and rehabilitative approaches. We conclude with a discussion on the positive impact of swallowing rehabilitation on malnutrition and pneumonia in elderly who either present with dysphagia or are at risk for dysphagia.Keywords: dysphagia, aging, malnutrition, pneumonia, rehabilitation

Acanthamoeba keratitis is a severe ocular infection that poses treatment challenges and can lead to blindness. Despite its ubiquity and potential contamination of contact lenses after water exposure, the natural behavior of this pathogen remains elusive. Understanding Acanthamoeba's movement patterns can inform us about how it colonizes contact lenses and contaminates the patient's cornea. It is fortunate that Acanthamoeba spp. are visible via brightfield microscopy starting at 4x magnification. Previous techniques have been developed to quantify Acanthamoeba motility in regard to cytopathic effects or under-exposure to the electric field. Here, we describe a method to track and quantify Acanthamoeba spp. motility long-term (hours to days), which is a protocol applicable to multiple amoeba strains, surfaces, and nutritional status of amoeba. This procedure is germane to determining many core motility quantifications, such as distance, speed, confinement, and directionality, which are necessary to monitor different stages of infection, proliferation, or behavioral change.

Submental surface electromyography (sEMG) may provide information about the lingual-palatal pressure (LPP) during swallowing. However, the extent to which changes in age and LPP levels are reflected in different sEMG measures is unclear. This study aimed to understand the effects of age and different levels of submaximal LPPs on submental sEMG peak, average, and integrated values in healthy adults. Ninety community-dwelling healthy participants were categorized into three age groups (young: 20-39 years, middle age: 40-59 years, older: 60 ≥ years). sEMG and LPP measurements were collected concurrently. After placing the sEMG electrodes, the maximal isometric LPP was established using the Iowa oral performance instrument (IOPI) on the anterior tongue. sEMG recordings were conducted for three submaximal LPP levels, including 40%, 60%, and 80% of the maximum LPP. Two-way repeated measure ANOVAs were conducted to find the effects of age and varying LPP levels on mean sEMG peak, average, and integrated measures. A significant age by LPP level interaction was identified for sEMG peak [F (4, 172) = 4.116, p < 0.007, ηp2 = 0.087], sEMG average [F (4, 170) = 5.049, p < 0.001, ηp2 = 0.106], and sEMG integrated values [F (4, 170) = 4.179, p < 0.003, ηp2 = 0.090]. Post hoc testing demonstrated that, in general, sEMG values significantly increased with rising LPP levels, primarily for younger and middle-aged adults. Furthermore, at 80% of maximum LPP, older adults generated less sEMG average and integrated values than middle age (only significant for sEMG integrated value) and younger adults. Likewise, max LPP was lower in older adults compared with young and middle-aged groups. Submental sEMG has the potential to be incorporated into a skill-based lingual exercise paradigm to improve tongue function during swallowing. Moreover, submental sEMG can characterize some age-related subclinical changes in swallowing., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Pseudomonas aeruginosa is the most common causative agent associated with microbial keratitis. During contact lens wear, pathogens may be introduced into the ocular environment, which might cause adverse events. Lehfilcon A is a recently developed contact lens with a water gradient surface composed of polymeric 2-methacryloyloxyethyl phosphorylcholine (MPC). MPC is re-ported to impart anti-biofouling properties onto modified substrates. Therefore, in this in vitro experimental study, we tested the capability of lehfilcon A to resist adhesion by P. aeruginosa . Quantitative bacterial adhesion assays using five strains of P. aeruginosa were conducted to compare the adherence properties of lehfilcon A to five currently marketed silicone hydrogel (SiHy) contact lenses (comfilcon A, fanfilcon A, senofilcon A, senofilcon C, and samfilcon A). Compared to lehfilcon A, we observed 26.7 ± 8.8 times ( p = 0.0028) more P. aeruginosa binding to comfilcon A, 30.0 ± 10.8 times ( p = 0.0038) more binding to fanfilcon A, 18.2 ± 6.2 times ( p = 0.0034) more binding to senofilcon A, 13.6 ± 3.9 times ( p = 0.0019) more binding to senofilcon C, and 29.5 ± 11.8 times ( p = 0.0057) more binding to samfilcon A. These results demonstrate that, for various strains of P. aeruginosa , lehfilcon A reduces bacterial adhesion compared to other contact lens materials.

Acanthamoeba keratitis is a sight-threatening infection of the cornea which is extremely challenging to treat. Understanding this organism's responses during contact lens contact and disinfection could enhance our understanding of how Acanthamoebae colonize contact lens cases, better inform us on contact lens care solution (CLC) efficacy, and help us better understand the efficacy required of CLC products. To explore this gap in knowledge, we used Acanthamoeba ATCC 30461 and ATCC 50370 trophozoites to examine Acanthamoeba behavior during and after CLC disinfection. Amoebae were added to sterile aluminum flow cells and flow cell solutions were changed to Ringer's solution (control), or one of four CLCs based on biocides (PHMB, PAPB/Polyquad, Polyquad/Aldox, or Polyquad/Alexidine) for 6 h. Each flow cell solution was then changed to axenic culture media (AC6) for 12 h to determine the behavior of amoebae following disinfection. Distance, speed, and displacement were calculated for each organism. As compared to the control of one-quarter Ringer's solution, each CLC significantly impacted Acanthamoeba motility in both the CLC and AC6 conditions. However, the amoebae challenged with the PHMB CLC traveled a significantly greater total distance than with the other three CLCs, indicating differences in effectiveness between biocides. Furthermore, amoebae regaining motility post-disinfection by CLCs were observed to travel considerable distances and thus could be considered dangerous to ocular health. We determined that while all CLCs produced a substantial or complete cessation of movement vs. the control condition during disinfection, those which relied on the Polyquad biocides were the most effective, and that any amoebae which survived disinfection were able to recover motility. Future examinations of these findings should include direct correlations between motility and viability, and how infectivity and motility may be related.

Bacterial keratitis is a risk associated with the use of contact lenses for cosmetic purposes or vision correction. In this in vitro experimental study, we examined the ability of the ocular pathogen Serratia marcescens to adhere to monthly or biweekly replacement contact lenses. We performed quantitative adhesion assays to evaluate the adherence of S. marcescens to seven contact lens materials: comfilcon A, senofilcon A, omafilcon B, fanfilcon A, balafilcon A, senofilcon C, and lehfilcon A. Lehfilcon A is a newly marketed silicon hydrogel contact lens with a surface modification of poly-(2-methacryloyloxyethyl phosphorylcholine) (PMPC). PMPC has previously been demonstrated to be an effective anti-biofouling treatment for numerous surfaces. We observed low S. marcescens adherence to lehfilcon A compared to other materials. We demonstrate the use of the fluorescent dye 5(6)-Carboxytetramethylrhodamine succinimidyl ester to covalently stain live cells prior to material adhesion studies.

Introduction: Acanthamoeba keratitis is often caused when Acanthamoeba contaminate contact lenses and infect the cornea. Acanthamoeba is pervasive in the environment as a motile, foraging trophozoite or biocide-resistant and persistent cyst. As contact lens contamination is a potential first step in infection, we studied Acanthamoeba's behavior and interactions on different contact lens materials. We hypothesized that contact lenses may induce aggregation, which is a precursor to encystment, and that aggregated encystment would be more difficult to disinfect than motile trophozoites., Methods: Six clinically and/or scientifically relevant strains of Acanthamoeba (ATCC 30010, ATCC 30461, ATCC 50370, ATCC 50702, ATCC 50703, and ATCC PRA-115) were investigated on seven different common silicone hydrogel contact lenses, and a no-lens control, for aggregation and encystment for 72 h. Cell count and size were used to determine aggregation, and fluorescent staining was used to understand encystment. RNA seq was performed to describe the genome of Acanthamoeba which was individually motile or aggregated on different lens materials. Disinfection efficacy using three common multi-purpose solutions was calculated to describe the potential disinfection resistance of trophozoites, individual cysts, or spheroids., Results: Acanthamoeba trophozoites of all strains examined demonstrated significantly more aggregation on specific contact lens materials than others, or the no-lens control. Fluorescent staining demonstrated encystment in as little as 4 hours on contact lens materials, which is substantially faster than previously reported in natural or laboratory settings. Gene expression profiles corroborated encystment, with significantly differentially expressed pathways involving actin arrangement and membrane complexes. High disinfection resistance of cysts and spheroids with multi-purpose solutions was observed., Discussion: Aggregation/encystment is a protective mechanism which may enable Acanthamoeba to be more disinfection resistant than individual trophozoites. This study demonstrates that some contact lens materials promote Acanthamoeba aggregation and encystment, and Acanthamoeba spheroids obstruct multi-purpose solutions from disinfecting Acanthamoeba ., Competing Interests: The funder was not involved in the study design, collection, analysis, interpretation of data, or the writing of this article. The funder approved the decision to submit for publication. All authors except CR are employees of Alcon Research. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Campolo, Pifer, Walters, Thomas, Miller, Harris, King, Rice, Shannon, Patterson and Crary.)

Microbial keratitis (MK), the infection of the cornea, is a devastating disease and the fifth leading cause of blindness and visual impairment around the world. The overwhelming majority of MK cases are linked to contact lens wear combined with factors which promote infection such as corneal abrasion, an immunocompromised state, improper contact lens use, or failing to routinely disinfect lenses after wear. Contact lens-related MK involves the adherence of microorganisms to the contact lens. Therefore, this review discusses the information currently available regarding the disease pathophysiology, the common types of microorganisms causing MK, physical and organic mechanisms of adhesion, material properties which are involved in adhesion, and current antimicrobial strategies. This review also concludes that Pseudomonas aeruginosa is a model organism for the investigation of contact lens microbial adherence due to its prevalence in MK cases, its extremely robust adhesion, antimicrobial-resistant properties, and the severity of the disease it causes.

Objective: Sight-threatening infections can be caused by pathogenic micro-organisms colonising the cornea, leading to microbial keratitis (MK). These micro-organisms can be introduced to the eye via improper contact lens use and care. MK can also result from ineffective contact lens care solutions (CLCs), even if the patient is following best practice guidelines. Therefore, it is critical to understand the differences between the effectiveness of popular CLCs on the global market., Methods and Analysis: Following the International Standards Organisation standards 14 729 and 18259, bacteria ( Pseudomonas aeruginosa, Serratia marcescens, Staphylococcus aureus ), fungi ( Candida albicans, Fusarium strains) and Acanthamoeba strains were inoculated into each CLC with and without contact lenses, and held for the manufacturer's stated disinfection time. Plate counts were conducted to determine the number of surviving micro-organisms., Results: All CLCs examined met the primary log reduction criteria during stand-alone testing for Pseudomonas, Staphylococcus, Candida and Fusarium . renu Multiplus, All Clean Soft, and Kombilösung Super did not meet the primary criteria when challenged with Serratia . Only OPTI-FREE Express exceeded 4 log reduction for both strains of Acanthamoeba tested. We noted a substantial reduction in disinfection efficacy when CLCs were challenged with Fusarium in the presence of lenses and cases versus stand-alone testing. OPTI-FREE Express demonstrated significantly less net log reduction loss than the other four CLCs tested., Conclusion: Of the popular CLCs on the global market, the product which relies on dual biocides polyquaternium-1 and myristamidopropyl dimethylamine demonstrated the highest disinfection efficacy in microbial disinfection challenges in the absence and presence of contact lenses., Competing Interests: Competing interests: All authors are/were employees of Alcon Research., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: This study sought to evaluate the role and trajectory of spontaneous swallowing frequency (SFA) in patients with head and neck cancer (HNC) undergoing chemoradiotherapy (C/RT). Study Design . Prospective cohort., Setting: University comprehensive cancer center., Methods: A prospective cohort of 80 patients with HNC was followed from baseline to 3 months post-C/RT. Subjects were evaluated for performance on swallowing function, functional diet consumed, weight, swallowing frequency rate, perceived xerostomia, perceived pain, and mucositis. Relationships were evaluated using univariate correlations, t tests, and repeated-measures analysis of variance. The diagnostic accuracy of SFA to express dysphagia was calculated by area under the curve (AUROC) and displayed using receiver operator characteristic curves., Results: In general, patients with HNC demonstrated a parabolic decline in most measures over the C/RT trajectory. SFA and perceived xerostomia did not show improved recovery by 3 months. SFA was related to swallow function, xerostomia, and functional diet consumed posttreatment and pain at 3 months. The ability of SFA to correctly identify clinical dysphagia (Mann Assessment of Swallowing-Cancer version [MASA-C]) and reduced oral intake (Functional Oral Intake Scale [FOIS]) at posttreatment was strong (AUROC MASA-C: 0.824 [95% CI, 0.63-1.00], P < .0018; AUROC FOIS: 0.96 [95% CI, 0.87-0.96], P < .0001)., Conclusion: This exploratory study suggests SFA may provide a useful method to identify dysphagia after HNC treatment. Furthermore, SFA may offer a simple, objective measure of swallowing function change in HNC over the C/RT trajectory.

Microbial keratitis is a devastating disease that can cause eye damage and blindness and can be the result of infections by several common ocular pathogens. Importantly, some of these pathogens, such as Acanthamoeba , are particularly unsusceptible to biocides in common contact lens care solutions. Therefore, the disinfection efficacy of preservative-free (PF) disinfection systems against bacteria, fungi, and Acanthamoeba trophozoites and cysts should be assessed as products with the most potential to be efficacious against resistant organisms. PF disinfection systems were analyzed for antimicrobial efficacy. These were the one-step (hydrogen peroxide-based) Clear Care and Clear Care Plus systems and the two-step (povidone-iodine-based) Cleadew system. Stand-alone challenges using bacteria, fungi, and Acanthamoeba were prepared according to the International Standards Organization method 14729. These same challenges were also conducted in the presence of the following contact lenses: Boston RGP, Acuvue Oasys, Biofinity, Ultra, and 2-week PremiO. All challenges were performed at the manufacturer's recommended disinfection time. All preservative-free disinfection systems demonstrated similarly high rates of antimicrobial efficacy when challenged with bacteria or fungi, with or without lenses. However, both Clear Care and Clear Care Plus demonstrated significantly greater disinfection efficacy against Acanthamoeba trophozoites and cysts, with and without lenses ( P  < 0.05). Cleadew efficacy was impacted by the addition of contact lenses, whereas Clear Care/Clear Care Plus maintained similar efficacies in the absence or presence of lenses. While both hydrogen peroxide and povidone-iodine are highly effective against bacteria and fungi, hydrogen peroxide maintains significantly greater disinfection capabilities than povidone-iodine against all forms of Acanthamoeba . IMPORTANCE Understanding the most efficacious products will allow clinicians to best communicate to patients and consumers the safest products on the market to reduce adverse events, including microbial keratitis, during contact lens use.

Significance: This investigation examines the effectiveness of several common contact lens solutions in the disinfection of Acanthamoeba, which causes a serious eye infection most often resulting from dysfunctional or improper use of contact lens products., Purpose: Acanthamoeba keratitis is an eye infection caused by a free-living amoeba, which can lead to extensive corneal damage and frequently blindness. Acanthamoeba keratitis is linked with contact lens use combined with noncompliance with contact lens care cleaning regimens. The patient's choice and use of multipurpose solutions (MPSs) continue to be a risk factor for Acanthamoeba keratitis. Thus, it is critical that the Acanthamoeba disinfection efficacy of the popular MPSs be determined. Here we compare the efficacy of seven major MPSs on the global market., Methods: Using standard methods of Acanthamoeba disinfection and quantification, Acanthamoeba ATCC 30461, 30868, 50370, and 50676 trophozoites were inoculated into each MPS and held for the manufacturer's recommended disinfection time. Acanthamoeba recovery plates were incubated for 14 days, after which positive wells were identified and cell concentrations determined using the 50% endpoint method., Results: Members of the OPTI-FREE products (Express, Replenish, and Puremoist [Alcon, Fort Worth, TX]) demonstrated significantly higher percentages of antimicrobial activity compared with the renu Advanced Formula (Bausch + Lomb, Rochester, NY), Biotrue (Bausch + Lomb), Acuvue RevitaLens (Johnson & Johnson, Santa Ana, CA), and Lite products (Cooper Vision, Scottsville, NY) for four of the trophozoite strains tested., Conclusions: Many of the popular MPS biocides maintain little or no antimicrobial activity against Acanthamoeba trophozoites, and the number of biocides in an MPS does not necessarily indicate its antimicrobial activity., Competing Interests: Conflict of Interest Disclosure: All authors are employees of Alcon Research LLC. The authors have full access and control of the data reported in the study and take full responsibility for their presentation in this article. Alcon Research LLC funded the study., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Optometry.)

Microbial keratitis (MK) is an eye infection caused by opportunistic bacteria or fungi, which may lead to sight-threatening corneal ulcers. These microorganisms can be introduced to the eye via improper contact lens usage or hygiene, or ineffective multipurpose solutions (MPSs) to disinfect daily wear contact lenses. Thus, the patient's choice and use of these MPSs is a known risk factor for the development of MK. It is then critical to determine the efficacy of popular MPSs against ubiquitous ocular microorganisms. Therefore, we compare the efficacy of nine major MPSs on the global market against four different microorganism species, and with four different common contact lenses. In accordance with International Standards Organization protocol 14729 and 18259, the microorganisms were inoculated into each MPS with and without contact lenses, and held for the manufacturer's disinfection time, 24 h, and 7 days after challenge with Serratia marcescens or Fusarium spp. Plates were incubated for 2-7 days and plate counts were conducted to determine the number of surviving microorganisms. The majority of MPSs demonstrated significantly higher disinfection efficacies without contact lenses. Broadly, among the microorganisms tested, the OPTI-FREE products (Puremoist, Express, and Replenish) maintained the highest disinfection efficacies at the manufacturer's stated disinfection time when paired with any contact lens, compared with other MPSs. These were followed closely by RevitaLens and renu Advanced. MPSs containing dual biocides polyquaternium-1 and myristamidopropyl dimethylamine possessed the highest disinfection efficacy against multiple ocular pathogens.

Acanthamoeba keratitis is a serious ocular infection which is challenging to treat and can lead to blindness. While this pathogen is ubiquitous and can contaminate contact lenses after contact with water, its habits remain elusive. Understanding this organism's natural behavior will better inform us on how Acanthamoeba colonize contact lens care systems. Acanthamoeba trophozoites were allowed to adhere to either a glass coverslip or non-nutrient agar (NNA) within a flow cell with nutrients ( Escherichia coli or an axenic culture medium (AC6)) or without nutrients (Ringer's solution). Images were taken once every 24 s over 12 h and compiled, and videos were analyzed using ImageJ Trackmate software. Acanthamoeba maintained continuous movement for the entire 12 h period. ATCC 50370 had limited differences between conditions and surfaces throughout the experiment. Nutrient differences had a noticeable impact for ATCC 30461, where E. coli resulted in the highest total distance and speed during the early periods of the experiment but had the lowest total distance and speed by 12 h. The Ringer's and AC6 conditions were the most similar between strains, while Acanthamoeba in the E. coli and NNA conditions demonstrated significant differences between strains ( p < 0.05). These results indicate that quantifiable visual tracking of Acanthamoeba may be a novel and robust method for identifying the movement of Acanthamoeba in relation to contact lens care products. The present study indicates that Acanthamoeba can undertake sustained movement for at least 12 h with and without nutrients, on both rough and smooth surfaces, and that different strains have divergent behavior.

Acanthamoeba keratitis (AK) is a serious ocular infection caused by a ubiquitous free-living amoeba, Acanthamoeba . This infection often results in extensive corneal damage and blindness, and is notoriously difficult to cure. While Acanthamoeba is an abundant organism, AK is most associated with contact lens hygiene noncompliance and inadequate contact lens care (CLC) disinfection regimens. Thus, accurate and timely antimicrobial efficacy testing of CLC solutions is paramount. Published methods for antimicrobial efficacy testing of Acanthamoeba trophozoites requires 14 days for results. Presently, alternate and/or rapid methods for evaluating CLC products rarely demonstrate equivalent results compared to commonly-reported methods. Propidium iodide is a cellular stain that can only bind to cells with damaged outer membranes. We evaluated propidium iodide staining as an alternative method for determining the relative antimicrobial efficacy of 11 different CLC products against Acanthamoeba trophozoites. Following exposure to a CLC product, the fluorescence intensity of propidium iodide in an Acanthamoeba population demonstrated a strong correlation to the log reduction determined by established, growth-based Acanthamoeba testing used to evaluate the antimicrobial efficacy of CLC products. Thus, propidium iodide was found to be an effective rapid tool for determining cell death in Acanthamoeba trophozoites following exposure to CLC solutions.

Purpose This clinical focus article considers the roles of the clinical swallow examination (CSE) as a clinically meaningful assessment method used in both adult and pediatric populations. Method This clinical focus article explores the utility of the CSE across the life span. Specifically, components, reliability, standardized assessments, and limitations of the CSE within the adult and pediatric populations are highlighted. Conclusions The CSE remains a crucial assessment tool for the speech-language pathologist. The experienced clinician can make important judgments regarding patient safety and function. If the CSE is conducted mindfully and methodically, findings can help chart the course of care for individuals needing additional assessment and possibly intervention.

Transcutaneous electrical stimulation (TES) is a frequently used adjunctive modality in dysphagia rehabilitation. Stimulating deeper swallowing muscles requires higher TES amplitude. However, TES amplitude is limited by maximum amplitude tolerance (MAT). Previous studies have reported high interindividual variability regarding MAT and perceived discomfort. This variability might be one of the potential reasons of conflicting outcomes in TES-based swallowing studies. MAT and perceived discomfort are influenced by a variety of biopsychological factors. The influence of these factors related to swallow applications is poorly understood. This study explored the relation of biopsychological factors with MAT and perceived discomfort related to TES in the submental area. A convenience sample of thirty community-dwelling older adults between 60 and 70 years of age provided data for this study. Gender, submental adipose tissue thickness, perceptual pain sensitivity, and pain-coping strategies were evaluated for each subject. Subsequently, MAT and perceived discomfort level were determined using TES on the submental area. Relation of different biopsychological variables with MAT and discomfort level was examined using Pearson and Spearman correlation, and Mann-Whitney U test. Results indicated that neither gender nor adipose thickness was related to MAT and perceived discomfort. Among studied pain-coping strategies, catastrophizing was significantly related to MAT(r = - 0.552, p < .002). Distraction was significantly related to perceived discomfort level (r = - 0.561, p < 0.002). Given the negative impact of pain catastrophizing on MAT and the positive impact of distraction on perceiving discomfort, these coping strategies should be considered as amplitude-limiting and discomfort-moderating factors in TES-based dysphagia rehabilitation.

Background: Dysphagia following stroke is prevalent; however, dysphagia treatment is often applied haphazardly and outcomes unclear. Neuromuscular electrical stimulation (NMES) has received increased attention as a treatment for post-stroke dysphagia; but application data remain conflicted., Objective: This study investigated effectiveness and safety of an exercise-based swallowing therapy (McNeill Dysphagia Therapy: MDTP) +NMES for dysphagia rehabilitation following stroke., Methods: Stroke patients (n = 53, x̅ age: 66 [13.2], 47.2% male) with dysphagia admitted to sub-acute rehabilitation hospital were randomised to MDTP + NMES [NMES], MDTP + sham NMES [MDTP] or usual care [UC] swallowing therapy groups. Patients were treated for 1 hour per day for 3 weeks and monitored to 3 months by a blinded evaluator. Outcomes included clinical swallowing ability, oral intake, weight, patient perception of swallow and occurrence of dysphagia-related complications., Results: Post-treatment dysphagia severity and treatment response were significantly different between groups (P ≤ .0001). MDTP demonstrated greater positive change than either NMES or UC arms, including increase in oral intake (χ 2  = 5, P ≤ .022) and improved functional outcome by 3 months post-stroke (RR = 1.72, 1.04-2.84). Exploratory Cox regression revealed the MDTP group conferred the greatest benefit in time to "return to pre-stroke diet" of 4.317 [95% CI: 1.08- 17.2, P< .03]., Conclusion: Greater benefit (eg reduction in dysphagia severity, improved oral intake and earlier return to pre-stroke diet) resulted from a programme of MDTP alone vs NMES or UC., (© 2019 John Wiley & Sons Ltd.)

Limited research in swallowing physiology has suggested that the most common existing transcutaneous electrical stimulation (TES) protocol (VitalStim) may not penetrate to layers of tissue to affect deep swallowing muscles. TES amplitude is the primary parameter that determines the depth of electrical current penetration (DECP). Preliminary work suggests that replacing a long-pulse duration with a short-pulse duration can increase maximum amplitude tolerance (MAT) within subjects' comfort level. Increasing MAT may indicate a higher DECP. The current study evaluates this premise in reference to the effects of varying pulse duration on lingual-palatal pressure during swallowing. Thirty healthy older adults (60-70 years of age) participated in this study. Each subject swallowed three trials of 10 mL pudding under three TES conditions: no stimulation, short-pulse duration, and long-pulse duration. TES was delivered using two pairs of surface electrodes on the submental muscles. MAT and perceived discomfort levels were identified separately for short and long-pulse TES conditions. Lingual-palatal peak pressure, pressure integral, and pressure duration were measured under each condition. Two-way repeated measures ANOVAs were conducted to identify within subject effects of TES condition and tongue bulb location. Lingual-palatal pressure and pressure integral were significantly reduced in the short-pulse duration condition. MAT was significantly higher in the short-pulse duration versus the long-pulse duration condition. Furthermore, MAT was significantly correlated with lingual-palatal pressure. Changing pulse duration had no significant impact on tongue pressure duration. Results suggest that a short-pulse duration may penetrate deeper into muscles involved in swallowing. The specific impact is reflected in a reduced upward pressure of the tongue on the palate during swallowing. This 'restrictive' effect of TES on tongue pressure may have the potential to be used during a resistive exercise paradigm for tongue elevation during swallowing.

Objective: To expand the scope of prior spontaneous swallowing frequency analysis (SFA) studies, by evaluating the role of SFA in dysphagia-and stroke-related outcomes at acute stroke discharge., Design: Period prevalence study., Setting: Tertiary care university hospital., Participants: Patients with acute stroke (N=96)., Interventions: Subjects were screened for dysphagia using SFA. Mode of screening was 24 hours from identified stroke onset. All patients completed dysphagia- and stroke-related assessments. Patients were followed to discharge from acute care, and admission SFA was compared with status at discharge., Results: Lower SFA rates at admission were significantly associated with presence of dysphagia. Lower SFA rates were also associated with persistent dysphagia and restricted diet at discharge. The SFA rates were lower for patients with identified aspiration on fluoroscopic swallowing study. Negative stroke-related outcomes from acute care were associated with lower SFA rates including disability at admission, disability and handicap at discharge, and institutionalization at discharge. Regression analysis identified SFA as an independent predictor of the negative composite outcome of death-disability-institutionalization., Conclusions: Swallowing frequency analysis not only has a high accuracy of dysphagia identification in acute stroke and relates to dysphagia severity, but it is also associated with multiple dysphagia- and stoke-related outcomes from acute care. Early poststroke dysphagia identification with SFA may lead to earlier and more effective interventions targeted at identified negative stroke outcomes., (Copyright © 2019 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the antimicrobial effects of CLEAR CARE, a 3% hydrogen peroxide (H2O2) solution formulated for simultaneous cleaning, daily protein removal, disinfection, and storage of soft (hydrophilic) hydrogel, silicone hydrogel, and gas-permeable contact lenses, and CLEAR CARE PLUS, consisting of the 3% H2O2 solution plus a novel wetting agent, polyoxyethylene-polyoxybutylene (EOBO-21)., Methods: Three lots each of the 2 solutions were incubated with 5 compendial microorganisms required by the Food and Drug Administration (FDA) 510(k) and International Organization for Standardization (ISO) 14729 stand-alone procedures, 4 clinical isolates of Gram-positive and Gram-negative bacteria, and trophozoites and cysts of 2 Acanthamoeba strains that are associated with microbial keratitis. Microbial loads were evaluated after disinfection and neutralization., Results: Both solutions exceeded the FDA/ISO stand-alone primary criteria against Gram-positive and Gram-negative compendial bacteria, yeast, and mold after only 1.5-hr disinfection/neutralization. At the recommended minimum disinfection time, bacteria were reduced by 4.4 to 5.1 logs, yeast by 4.4 to 4.9 logs, and mold by 2.9 to 3.5 logs with and without organic soil. In addition, both solutions eliminated or effectively reduced populations of clinically relevant ocular bacterial isolates (4.5-5.0 logs), Acanthamoeba trophozoites (3.4-4.2 logs), and cysts (1.5-2.1 logs)., Conclusion: Both solutions eliminated or reduced populations of FDA/ISO compendial bacteria and fungi as well as clinically relevant microorganisms and Acanthamoeba trophozoites and cysts. The addition of EOBO-21 to the 3% H2O2 lens care solution had no impact on antimicrobial activity.

Maximum amplitude tolerance (MAT) has been known as a primary factor determining the depth of electrical current penetration. However, the effect of varying transcutaneous electrical stimulation (TES) parameters on MAT and discomfort level is poorly understood. Furthermore, limited information exists regarding the biopsychological factors that may impact MAT and discomfort. The primary aims of this study were to compare the effects TES protocol with varying levels of pulse duration (300 μs vs 700 μs) and frequency (30 Hz vs 80 Hz) on the MAT and discomfort in healthy older adults. The exploratory aim of this study was to examine relationships between submental adipose tissue thickness, pain sensitivity and gender with MAT and discomfort. Twenty-four healthy older adults participated in this study. Transcutaneous electrical stimulation was delivered to the submental region. Maximum amplitude tolerance and discomfort were measured for each condition. Furthermore, submental adipose tissue thickness and pain sensitivity were measured for each subject. Maximum amplitude tolerance was significantly increased for the TES protocols with short-pulse duration [F (3, 69) = 38.695, P < .0001]. Discomfort was similar across different TES protocols. Submental adipose tissue thickness (r = .30, P < .003) and pain sensitivity (r = -.43, P < .0001) were related to MAT. Pain sensitivity rating was also related to discomfort (r = .45, P < .0001). In conclusion, using TES protocols with short-pulse duration may increase the MAT. Higher amplitude stimulation may increase the impact on deep swallowing muscles. In addition, submental adipose tissue thickness and pain sensitivity are potential biopsychological factors that may affect MAT and discomfort., (© 2018 John Wiley & Sons Ltd.)

The aim of this study was to compare current application, practice patterns, clinical outcomes, and professional attitudes of dysphagia practitioners regarding electrical stimulation (e-stim) therapy with similar data obtained in 2005. A web-based survey was posted on the American Speech-Language-Hearing Association Special Interest Group 13 webpage for 1 month. A total of 271 survey responses were analyzed and descriptively compared with the archived responses from the 2005 survey. Results suggested that e-stim application increased by 47% among dysphagia practitioners over the last 10 years. The frequency of weekly e-stim therapy sessions decreased while the reported total number of treatment sessions increased between the two surveys. Advancement in oral diet was the most commonly reported improvement in both surveys. Overall, reported satisfaction levels of clinicians and patients regarding e-stim therapy decreased. Still, the majority of e-stim practitioners continue to recommend this treatment modality to other dysphagia practitioners. Results from the novel items in the current survey suggested that motor level e-stim (e.g. higher amplitude) is most commonly used during dysphagia therapy with no preferred electrode placement. Furthermore, the majority of clinicians reported high levels of self-confidence regarding their ability to perform e-stim. The results of this survey highlight ongoing changes in application, practice patterns, clinical outcomes, and professional attitudes associated with e-stim therapy among dysphagia practitioners.

Objectives: This study compared the effect of transcutaneous electrical stimulation (TES) amplitude on timing of lingual-palatal and pharyngeal peak pressures during swallowing in healthy younger and older adults., Background: Transcutaneous electrical stimulation amplitude is one parameter that may have different impacts on the neuromotor system and swallowing physiology. One aspect of swallowing physiology influenced by age is the timing of swallowing events. However, the effect of varying TES amplitudes on timing of swallowing physiology is poorly understood, especially in older adults., Materials and Methods: Thirty-four adults (20 younger and 14 older) swallowed 10 ml of nectar-thick liquid under three TES conditions: no stimulation, low-amplitude stimulation and high-amplitude stimulation. TES was delivered by surface electrodes on the anterior neck. Timing of pressure peaks for lingual-palatal contacts and pharyngeal pressures were measured under each condition., Results: A significant age × stimulation amplitude interaction was identified for the base of tongue (BOT) [F(2,62) = 5.087, p < 0.009] and the hypopharynx (HYPO) [F(2,62) = 3.277, p < 0.044]. At the BOT, low-amplitude TES resulted in slower swallows in the younger adults compared with no TES. In older adults, low-amplitude TES resulted in faster swallows compared with high-amplitude TES. At the HYPO, no significant differences were identified in pressure timing across the three TES amplitudes in both age groups. In each case, low-amplitude TES resulted in faster swallows in older adults compared with younger adults., Conclusions: Transcutaneous electrical stimulation influences pharyngeal pressure timing differently in young and old people, which questions the appropriateness of using a 'one-size-fits-all' TES amplitude for rehabilitating people with dysphagia., (© 2015 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.)

Objective/hypothesis: Patients with laryngeal disorders often exhibit changes to cough function contributing to aspiration episodes. Two primary cough variables (peak cough flow: PCF and compression phase duration: CPD) were examined within a biomechanical model to determine their impact on characteristics that impact airway compromise., Study Design: Computational study., Methods: A Computational Fluid Dynamics (CFD) technique was used to simulate fluid flow within an upper airway model reconstructed from patient CT images. The model utilized a finite-volume numerical scheme to simulate cough-induced airflow, allowing for turbulent particle interaction, collision, and break-up. Liquid penetrants at 8 anatomical release locations were tracked during the simulated cough. Cough flow velocity was computed for a base case and four simulated cases. Airway clearance was evaluated through assessment of the fate of particles in the airway following simulated cough., Results: Peak-expiratory phase resulted in very high airway velocities for all simulated cases modelled. The highest velocity predicted was 49.96 m/s, 88 m/s, and 117 m/s for Cases 1 and 3, Base case, and Cases 2 and 4 respectively. In the base case, 25% of the penetrants cleared the laryngeal airway. The highest percentage (50%) of penetrants clearing the laryngeal airway are observed in Case 2 (with -40% CPD, +40% PCF), while only 12.5% cleared in Case 3 (with +40% CPD, -40% PCF). The proportion that cleared in Cases 1 and 4 was 37.5%., Conclusion: Airway modelling may be beneficial to the study of aspiration in patients with impaired cough function including those with upper airway and neurological diseases. It can be used to enhance understanding of cough flow dynamics within the airway and to inform strategies for treatment with "cough-assist devices" or devices to improve cough strength., Level of Evidence: N/A.

Reduced movement velocity has been identified as a risk marker for movement impairment in older adults. Hyolaryngeal excursion is a key movement feature of normal swallowing function which is known to change with age and other extrinsic variables such as bolus volume. However, velocity of hyolaryngeal excursion has received limited attention in the literature on normal or abnormal swallowing. This study evaluated the effects of age and bolus volume on the velocity of hyoid and laryngeal excursion during swallowing in healthy adults. Forty-four healthy volunteers were grouped into three age bands (young: 20-35 years, middle age: 36-55 years, older: 56 ≥ years). All subjects swallowed 5 and 20 mL of thin liquid during fluoroscopic recording. Fluoroscopic images were extracted for each swallow representing the onset and maximum excursion positions of the hyoid and larynx. Superior and anterior excursion distance (excursion magnitude) and the time difference between rest and maximum excursion (excursion duration) were calculated. Velocity was calculated as a ratio of distance over time. Superior hyoid excursion magnitude was significantly increased for the 20 mL volume. Anterior laryngeal excursion magnitude was also significantly increased for the 20 mL volume. No kinematic duration measure demonstrated significant change across age or bolus conditions. Superior hyoid excursion velocity was significantly faster for the 20 mL volume. Superior and anterior laryngeal excursion velocity were significantly faster for the 20 mL volume only in the older group. Results of this study indicate that magnitude and velocity of hyoid and laryngeal excursion vary with age and volume. Comprising both excursion magnitude and duration, kinematic velocity may be a more complete metric to evaluate age-related swallowing performance.

Purpose: This article investigated the effects of increased oral lingual pressure on pharyngeal pressures during swallowing in patients who have undergone radiotherapy for head and neck cancer. It was hypothesized that increased oral lingual pressure would result in increased pharyngeal pressures., Method: A within-subject experimental design was used with 20 participants who were status post external beam radiotherapy for head and neck cancer. Participants completed typical swallows and swallows with increased lingual force during manofluoroscopic swallow studies. The swallow condition order was randomized across participants., Results: Manometric data revealed significant differences in swallow pressure by condition at the base of tongue and upper esophageal sphincter sensor locations without significant pressure differences in the lower pharynx. The effortful lingual swallows resulted in higher mean pressures at all locations., Conclusions: The results of this study suggest that use of a maneuver designed to increase oral tongue effort can also increase pharyngeal tongue base pressure. Therefore, therapeutic activities used to generate greater pressure of the oral tongue may also alter pharyngeal response. Further research is needed to determine the direct clinical effect on swallow function for individuals with head and neck cancer.

Species of Acanthamoeba were first described using morphological characters including cyst structure and cytology of nuclear division. More than 20 nominal species were proposed using these methods. Morphology, especially cyst shape and size, has proven to be plastic and dependent upon culture conditions. The DNA sequence of the nuclear small-subunit (18S) rRNA, the Rns gene, has become the most widely accepted method for rapid diagnosis and classification of Acanthamoeba. The Byers-Fuerst lab first proposed an Rns typing system in 1996. Subsequent refinements, with an increasing DNA database and analysis of diagnostic fragments within the gene, have become widely accepted by the Acanthamoeba research community. The development of the typing system, including its current state of implementation is illustrated by three cases: (i) the division between sequence types T13 and T16; (ii) the diversity within sequence supertype T2/T6, and (iii) verification of a new sequence type, designated T20. Molecular studies make clear the disconnection between phylogenetic relatedness and species names, as applied for the genus Acanthamoeba. Future reconciliation of genetic types with species names must become a priority, but the possible shortcomings of the use of a single gene when reconstructing the evolutionary history of the acanthamoebidae must also be resolved., (© 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.)

Ebola virus (EBOV) causes a lethal hemorrhagic fever for which there is no approved effective treatment or prevention strategy. EBOV VP35 is a virulence factor that blocks innate antiviral host responses, including the induction of and response to alpha/beta interferon. VP35 is also an RNA silencing suppressor (RSS). By inhibiting microRNA-directed silencing, mammalian virus RSSs have the capacity to alter the cellular environment to benefit replication. A reporter gene containing specific microRNA target sequences was used to demonstrate that prior expression of wild-type VP35 was able to block establishment of microRNA silencing in mammalian cells. In addition, wild-type VP35 C-terminal domain (CTD) protein fusions were shown to bind small interfering RNA (siRNA). Analysis of mutant proteins demonstrated that reporter activity in RSS assays did not correlate with their ability to antagonize double-stranded RNA (dsRNA)-activated protein kinase R (PKR) or bind siRNA. The results suggest that enhanced reporter activity in the presence of VP35 is a composite of nonspecific translational enhancement and silencing suppression. Moreover, most of the specific RSS activity in mammalian cells is RNA binding independent, consistent with VP35's proposed role in sequestering one or more silencing complex proteins. To examine RSS activity in a system without interferon, VP35 was tested in well-characterized plant silencing suppression assays. VP35 was shown to possess potent plant RSS activity, and the activities of mutant proteins correlated strongly, but not exclusively, with RNA binding ability. The results suggest the importance of VP35-protein interactions in blocking silencing in a system (mammalian) that cannot amplify dsRNA.

Members of the genus Acanthamoeba are usually free-living amoebae that are found in a variety of ecological niches including soil, fresh and brackish water, dust in the air, heating, ventilating, and air conditioning filters, swimming pools and hot tubs. Occasionally they are also known to cause central nervous system infections in humans and animals. We isolated into culture an amoeba from the liver of a Temminck's tragopan (horned pheasant) (Tragopan temminckii) that died of amoebic infection. We identified the infecting amoeba as Acanthamoeba sp. based on culture characteristics, cyst morphology and immunofluorescence assays. Additionally, we identified the amoeba as Acanthamoeba, genotype T4, by sequencing a diagnostic region of the nuclear small subunit ribosomal RNA gene., ((c) 2010 Elsevier B.V. All rights reserved.)

Background: Although many dysphagia screening protocols have been introduced in recent years, no validated, physician-administered dysphagia screening tool exists for acute stroke that can be performed at the bedside. Based on the psychometrically validated Mann Assessment of Swallowing Ability (MASA), we developed the Modified MASA (MMASA) as a physician-administered screening tool for dysphagia in acute stroke., Objective: The purpose of this study was to complete initial validation of this new screening tool for dysphagia in acute ischemic stroke., Methods: Two stroke neurologists independently performed the MMASA on 150 patients with ischemic stroke. Speech-language pathologists performed the standard MASA on all patients. All examiners were blinded to the results of the other assessments. Interjudge reliability was evaluated between the neurologists. Validity between the screening tool (MMASA) and the clinical evaluation (MASA) was assessed with sensitivity/specificity and predictive value assessment., Results: Interobserver agreement between the neurologists using the MMASA was good (k=0.76; SE=0.082). Based on the comprehensive clinical evaluation (MASA), 36.2% of patients demonstrated dysphagia. Screening results from the neurologists (N1 and N2) identified 38% and 36.7% prevalence of dysphagia, respectively. Sensitivity (N1: 92%, N2: 87%), specificity (N1: 86.3%, N2: 84.2%), positive predictive value (N1: 79.4%, N2: 75.8%), and negative predictive value (N1: 95.3%, N2: 92%) were high between the screen and the comprehensive clinical evaluation., Conclusions: This preliminary study suggests that the MMASA is a potentially valid and reliable physician-administered screening tool for dysphagia in acute ischemic stroke. Use of this tool may facilitate earlier identification of dysphagia in patients with stroke prompting more rapid comprehensive evaluation and intervention., ((c) 2010 National Stroke Association. Published by Elsevier Inc. All rights reserved.)