Postural balance and oculomotor control are influenced by neck kinaesthetic functions in elite ice hockey players

BackgroundResearch indicates that neck kinaesthetic awareness plays an important role in oculomotor and balance control, however the relationship has not been studied in athletes. As performance in ice hockey demands visual perception acuity during skating, while constantly shifting between unilateral and bilateral stances in sports specific posture more in-depth relationship should be studied.Research questionWhat is the relationship between neck kinaesthetic awareness, postural balance and eye movement control in professional ice hockey players and non-trained individuals?MethodsIn this observational study, centre-of-pressure was measured using force plate in twenty-eight hockey players and thirty non-trained participants during different stances in eyes-opened and eyes-closed conditions. Butterfly test and Head-to-Neutral Relocation test were performed to assess neck kinaesthesia. Horizontal smooth pursuit eye movements were measured using video-oculography. Linear regression was used to determine the relationship between neck kinaesthesia, body sway and oculomotor control.ResultsTime-on-target in Butterfly test was able to predict low to medium proportions of variance in amplitude and velocity parameters for single leg stances in hockey players (R² = .220–.698). Head-to-Neutral Relocation test was able to predict low to medium proportion of variance in average eye movement velocity during first 100 milliseconds of smooth pursuit initiation for both groups (R² = .262–.541).SignificanceFindings from our study suggest that cervical spine afferent input plays an important role in maintaining unilateral postural balance in hockey players, with less evidence presented in controls. Sports specific posture or upper body loading could lead to adaptations in neck proprioception, not frequently considered when searching for balance related injury risk factors or performance deficits. Our study suggests, that in addition to balance control, neck kinaesthesia can also affect oculomotor performance which was present in both groups. This is especially evident when initiating changes in eye movement direction.     

Exploring three levels of interoception in people with functional motor disorders

IntroductionA three-level model of interoception has recently been defined. We aim to study the interoceptive processing in individuals with functional motor disorder (FMD).MethodsTwenty-two patients with FMD were compared to 23 healthy controls. They underwent a protocol measuring different levels of interoception including: accuracy (a heart-beat tracking task), awareness (participant's confidence level) and sensibility (the Body Awareness Questionnaire-BAQ). Depression, anxiety and alexithymia were assessed by means of validated clinical scales.ResultsThe FMD group showed a lower cardiac interoceptive accuracy and sensibility than healthy controls but they did not differ in terms of awareness (p = 0.03 and 0.005 respectively). They were aware of their poor performance in the accuracy task. Cardiac interoceptive accuracy positively correlated with the BAQ sub-scales “Predict Body Reaction” (r = 0.49, p = 0.001) and “Sleep-Wake Cycle” (r = 0.52, p < 0.001). A mediation analysis showed a significant indirect effect of group on cardiac interoceptive accuracy through BAQ “Predict Body Reaction” (b = −2.95, 95% BCa CI[-7.2;-0.2]). The direct effect of group on “Predict Body Reaction” was still significant (b = − 6.95, p = 0.02, 95% CI[-13.18;-0.73]).ConclusionsPeople with FMD have impaired cardiac interoceptive accuracy and sensibility but no difference in metacognitive interoception compared to healthy controls.     

Research progress on the biomimetic remineralization of hard tooth tissues based on polyamide-amine dendrimer

聚酰胺—胺树枝状聚合物（PAMAM）作为一种新型超支化大分子聚合物,因其出色的化学和生物学特性,一直被众学者称之为“人工蛋白”。 PAMAM的特点是存在内部空腔,并含有大量的反应性末端基团,这些结构使得PAMAM可以被用作仿生大分子,模拟天然有机基质在牙体组织表面进行仿生矿化,即PAMAM作为有机模板调控矿物质成核以及晶体的生长,以此来建造比传统的异体材料更加理想的牙体修复材料。本文就 PAMAM 诱导牙体硬组织仿生矿化的研究进展作一综述。     

Resolving a 150-year-old paternity case in Mormon history using DTC autosomal DNA testing of distant relatives

Although autosomal DNA testing has been available for a number of years, its use to reconstruct genetic profiles of people that lived centuries in the past is relatively recent and there are no published cases where it was employed to verify a kinship relation, likely to be an alleged paternity, that occurred one and a half century ago.DNA testing has already been employed to study the ancestry and posterity of Joseph Smith Jr., founder of the Latter-day Saint (Mormon) movement. Thanks to information found on the paternally inherited Y chromosome, a number of alleged paternities have been disproved, but obviously this analysis is not effective for alleged daughters. Likewise, his reconstructed mitogenome sequence, reported here for the first time, provides information about his maternal ancestry, but is useless in any paternity questions due to the strict maternal inheritance. Among all the children attributed to Joseph Smith Jr., Josephine Lyon, born in 1844, is perhaps the most frequently mentioned.In the current study, 56 individuals, mostly direct descendants of Joseph Smith Jr. and Josephine Lyon, had their autosomal DNA tested to verify Josephine’s biological paternity. Nearly 600,000 autosomal SNPs from each subject were typed and detailed genealogical data were compiled. The absence of shared DNA between Josephine’s grandson and Joseph Smith Jr.’s five great-grandchildren together with various amounts of autosomal DNA shared by the same individual with four other relatives of Windsor Lyon is a clear indication that Josephine was not related to the Smith, but to the Lyon’s family. These inferences were also verified using kinship analyses and likelihood ratio calculations.