Differentiation of embryonic stem cells into a putative hair cell-progenitor cells via co-culture with HEI-OC1 cells

Several studies have shown how different cell lines can influence the differentiation of stem cells through co-culture systems. The House Ear Institute-Organ of Corti 1 (HEI-OC1) is considered an important cell line for in vitro auditory research. However, it is unknown if HEI-OC1 cells can promote the differentiation of embryonic stem cells (ESCs). In this study, we investigated whether co-culture of ESCs with HEI-OC1 cells promotes differentiation. To this end, we developed a co-culture system of mouse ESCs with HEI-OC1 cells. Dissociated or embryonic bodies (EBs) of ESCs were introduced to a conditioned and inactivated confluent layer of HEI-OC1 cells for 14 days. The dissociated ESCs coalesced into an EB-like form that was smaller than the co-cultured EBs. Contact co-culture generated cells expressing several otic progenitor markers as well as hair cell specific markers. ESCs and EBs were also cultured in non-contact setup but using conditioned medium from HEI-OC1 cells, indicating that soluble factors alone could have a similar effect. The ESCs did not form into aggregates but were still Myo7a-positive, while the EBs degenerated. However, in the fully differentiated EBs, evidence to prove mature differentiation of inner ear hair cell was still rudimentary. Nevertheless, these results suggest that cellular interactions between ESCs and HEI-OC1 cells may both stimulate ESC differentiation.

Bayesian Applications in Auditory Research

Purpose This article presents a basic exploration of Bayesian inference to inform researchers unfamiliar to this type of analysis of the many advantages this readily available approach provides. Method First, we demonstrate the development of Bayes' theorem, the cornerstone of Bayesian statistics, into an iterative process of updating priors. Working with a few assumptions, including normalcy and conjugacy of prior distribution, we express how one would calculate the posterior distribution using the prior distribution and the likelihood of the parameter. Next, we move to an example in auditory research by considering the effect of sound therapy for reducing the perceived loudness of tinnitus. In this case, as well as most real-world settings, we turn to Markov chain simulations because the assumptions allowing for easy calculations no longer hold. Using Markov chain Monte Carlo methods, we can illustrate several analysis solutions given by a straightforward Bayesian approach. Conclusion Bayesian methods are widely applicable and can help scientists overcome analysis problems, including how to include existing information, run interim analysis, achieve consensus through measurement, and, most importantly, interpret results correctly. Supplemental Material https://doi.org/10.23641/asha.7822592

Prosodical System of the Northern Aukštaitian dialect of Panevėžys of the Lithuanian Language

The Northern Aukštaitian dialect of Panevėžys of the Lithuanian Language is interesting in synchronic, diachronic, typological, and ethnogenetic aspects; its idioms bear some witness to contacts of Lithuanian and Semigalian languages (Kačiuškienė 2009). The secondary types of pitch accents of the Northern Aukštaitian dialect of Panevėžys were discussed in Dialectologia et Geolinguistica 24 (Kačiuškienė 2016). The auditory and instrumental research proved that two secondary types of pitch accents contrast in the pure and mixed diphthongs of the forms of some dialectal verbs and denominative words in the Northern Aukštaitian dialect of Panevėžys of the Lithuanian Language. This is a distinctive opposition. It is possible that the opposition relates to Proto-Baltic accentuation paradigms. The secondary types of pitch accents have different acoustic properties. The most distinct are the quantitative characteristics of diphthongs and characteristics of the fundamental pitch. The detailed analysis of the prosodic system of the Northern Panevėžys dialect in the present article is based on the data of the author’s native dialect and the instrumental and auditory research (see (Kačiuškienė 2006)). The results of the research of the Northern Aukštaitian dialect of Panevėžys are important to the comparative and historical dialectology of the Baltic languages; they can be used in typological research and in the classroom as teaching materials.