Decreased Maximal Tongue Protrusion Length May Predict the Presence of Dysphagia in Stroke Patients

Objective To investigate the relationship between maximal tongue protrusion length (MTPL) and dysphagia in post-stroke patients.Methods Free tongue length (FTL) was measured using the quick tongue-tie assessment tool and MTPL was measured using a transparent plastic ruler in 47 post-stroke patients. The MTPL-to-FTL (RMF) ratio was calculated. Swallowing function in all patients was evaluated via videofluoroscopic swallowing study (VFSS), PenetrationAspiration Scale (PAS), Functional Oral Intake Scale (FOIS), and Videofluoroscopic Dysphagia Scale (VDS).Results The MTPL and RMF values were significantly higher in the non-aspirator group than in the aspirator group (MTPL, p=0.0049; RMF, p<0.001). MTPL and RMF showed significant correlations with PAS, FOIS and VDS scores. The cut-off value in RMF for the prediction of aspiration was 1.56, with a sensitivity of 84% and a specificity of 86%.Conclusion There is a relationship between MTPL and dysphagia in post-stroke patients. MTPL and RMF can be useful for detecting aspiration in post-stroke patients.

Reduced Tongue Mobility: An Unrecognised Risk Factor of Childhood Obstructive Sleep Apnoea

Study Objectives Childhood obstructive sleep apnoea (OSA) is an important and prevalent disease. A short lingual frenulum is a risk factor for OSA, but whether tongue mobility also plays a role in OSA aetiology remains unknown. This study aimed to examine tongue mobility in children with and without OSA. We hypothesized that reduced tongue mobility was associated with OSA. We also evaluated the relationship between tongue mobility and craniofacial profile. Methods This was a cross-sectional case-control study. Prepubertal Chinese children aged 5-12 years, suspected to have OSA were recruited from our sleep disorder clinic. All subjects underwent overnight polysomnography (PSG). The lingual frenulum was evaluated based on tongue mobility and free tongue length. Craniofacial measurements were assessed by lateral cephalometry. Results Eighty-two subjects (mean age: 8.32 ± 1.70 years, 57 males) were recruited. The mean tongue mobility was 58.2 (±19)% and 67.4 (±15)% (p=0.019) in subjects with and without OSA, respectively. Tongue mobility was inversely correlated with OAHI (r=-0.218, p=0.049). In multivariate logistic regression, low tongue mobility was independently associated with a higher risk of OSA after adjustment for age, sex, BMI z-score, presence of large tonsils and turbinates and nocturnal oral breathing (odds ratio=3.65, 95% CI= 1.22-11.8). Tongue mobility was found to correlate with the cranial base angle (Ba-S-N) (r=0.262, p=0.018), which determines the relative position of the mandible. Conclusions In pre-pubertal children, reduced tongue mobility is associated with the occurrence and severity of OSA. Assessing tongue mobility is recommended in childhood OSA management.

Genome sequencing and morphometric analysis of alpine bumblebees experiencing climate change reveal ongoing phenotypic shifts and a lack of population structure

ABSTRACTPopulations of the bumblebees Bombus sylvicola and Bombus balteatus in Colorado have experienced decreases in tongue length, a trait important for plant-pollinator mutualisms, in the last six decades. It is hypothesized that this reflects selection exerted by changes in floral composition under climate change. Here we combine extensive morphometric and population genomic data to investigate population structure, whether morphological change is ongoing, and the genetic basis of morphological change. We generate highly-contiguous genome assemblies of both species using long-read sequencing. We then perform whole-genome sequencing and morphometric measurements of 580 samples of these species from seven high-altitude localities. Out of 281 samples originally identified as B. sylvicola, 67 formed a separate genetic cluster comprising the newly-discovered cryptic species B. incognitus. However, there is very little additional genetic substructure, suggesting that gene flow occurs readily between mountains. We find a significant decrease in tongue length between bees collected between 2008-2014 and in 2017, indicating that morphological shifts are ongoing. We did not discover any genetic associations with tongue length, but a SNP related to production of a proteolytic digestive enzyme is implicated in body size variation. We identify evidence of covariance between kinship and both tongue length and body size, which is suggestive of a genetic component of these traits, although it is not possible to rule out shared environmental effects between colonies. Our results provide evidence for ongoing evolution of a morphological trait important for pollination and indicate that this trait likely has a complex genetic and environmental basis.

The Effect of Frenotomy on the Tongue Length, Motion, and Speech According to Age

Background and Objectives Ankyloglossia often results in articulation disorders, which depends on age, articulation ability, and mobility of the tongue. A primary treatment strategy includes surgery and/or speech therapy. This study aimed to evaluate the changes of the tongue length, tongue mobility, and percentage of consonants correct (PCC) after frenotomy. We investigated the optimal surgery timing for ankyloglossia.Subjects and Method A total of 136 patients underwent frenotomy for the tongue tie between January 2016 and December 2019. There were 90 males and 46 females, with the mean age of 5.23, which ranged from 2 to 10 years. The length of the tongue was measured for all patients during the operation preoperatively and postoperatively. The mobility of the tongue and PCC were performed preoperatively and 1 month after surgery by two speech therapists. Patients were divided according to age into three groups: 2-3 years, 4-5 years, and over 6 years old.Results The mean tongue length of all age groups was significantly elongated after surgery (<i>p</i><0.05). After frenotomy, the mobility of tongue, including horizontal protrusion, protrusion with upward pointing, circumlocution, and lateral movement, was improved. Also, PCCs of all age groups were significantly improved after surgery (<i>p</i><0.05).Conclusion Frenotomy can be an effective procedure for children with ankyloglossia in all age groups. After frenotomy, length of the tongue, mobility of the tongue and PCC were significantly improved.

Measuring proboscis length in Lepidoptera: a review

Mouthpart morphologies relate to diet range. Differences among or within species may result in resource partitioning and speciation. In plant-pollinator interactions, mouthpart length has an important role in foraging efficiency, resource partitioning and pollination, hence measuring nectarivorous insect mouthparts’ morphological variation is important. Most adult lepidopterans feed on nectars and participate in pollination. Although a vast range of studies applied morphometric measurements on lepidopteran proboscis (tongue) length, general recommendations on methodologies are scarce. We review available proboscis length measurement methodologies for Lepidoptera. Focusing on how proboscides have been measured, how accurate the measurements were, and how were these constrained by sampling effort, we searched for research articles investigating lepidopteran proboscis length and extracted variables on the aims of measurements, preparation and measurement methodology, and descriptive statistics. Different methods were used both for preparation and measurements. Many of the 135 reviewed papers did not provide descriptions of the procedures applied. Research aims were different among studies. Forty-four percent of the studies measured dead specimens, 13% measured living specimens, and 43% were unclear. Fifteen percent of the studies used callipers, 9% rulers, 1% millimetre scales, 4% ocular micrometers, 3% drawings and 14% photographs; 55% were non-informative. We emphasise the importance to provide detailed descriptions on the methods applied. Providing guidelines for future sampling and measurements, we encourage fellow researchers planning measurements to take into account the effect of specimen preparation techniques on the results, define landmarks, consider resolution, accuracy, precision, choose an appropriate sample size and report details on methodology.

Unilateral lingual nerve transection alters jaw-tongue coordination during mastication in pigs

During chewing, movements and deformations of the tongue are coordinated with jaw movements to manage and manipulate the bolus and avoid injury. Individuals with injuries to the lingual nerve report both tongue injuries due to biting and difficulties in chewing, primarily because of impaired bolus management, suggesting that jaw-tongue coordination relies on intact lingual afferents. Here, we investigate how unilateral lingual nerve (LN) transection affects jaw-tongue coordination in an animal model (pig, Sus scrofa). Temporal coordination between jaw pitch (opening-closing) and 1) anteroposterior tongue position (i.e., protraction-retraction), 2) anteroposterior tongue length, and 3) mediolateral tongue width was compared between pre- and post-LN transection using cross-correlation analyses. Overall, following LN transection, the lag between jaw pitch and the majority of tongue kinematics decreased significantly, demonstrating that sensory loss from the tongue alters jaw-tongue coordination. In addition, decrease in jaw-tongue lag suggests that, following LN transection, tongue movements and deformations occur earlier in the gape cycle than when the lingual sensory afferents are intact. If the velocity of tongue movements and deformations remains constant, earlier occurrence can reflect less pronounced movements, possibly to avoid injuries. The results of this study demonstrate that lingual afferents participate in chewing by assisting with coordinating the timing of jaw and tongue movements. The observed changes may affect bolus management performance and/or may represent protective strategies because of altered somatosensory awareness of the tongue. NEW & NOTEWORTHY Chewing requires coordination between tongue and jaw movements. We compared the coordination of tongue movements and deformation relative to jaw opening-closing movements pre- and post-lingual nerve transection during chewing in pigs. These experiments reveal that the timing of jaw-tongue coordination is altered following unilateral disruption of sensory information from the tongue. Therefore, maintenance of jaw-tongue coordination requires bilateral sensory information from the tongue.