Respiratory internal kinematics of the tongue base and soft palate in obese minipigs with obstructive sleep apnea.

It is largely unknown how the tongue base and soft palate deform to alter the configuration of the oropharyngeal airway during respiration. This study is to address this important gap. After live sleep monitoring of five Yucatan and two Panepinto minipigs to verify obstructive sleep apnea (OSA), eight and four ultrasonic crystals were implanted into the tongue base and soft palate to circumscribe a cubic and square region, respectively. The 3D and 2D deformational changes of the circumscribed regions were measured simultaneously with electromyographic activity of the oropharyngeal muscles during spontaneous respiration under sedated sleep. The results indicated that both obese Yucatan and Panepinto minipigs presented spontaneous OSA, but not in three nonobese Yucatan minipigs. During inspiration, the tongue base showed elongation in both dorsal and ventral regions but thinning and thickening in the anterior and posterior regions, respectively. The widths showed opposite directions, widening in the dorsal but narrowing in the ventral regions. The soft palate expanded in both length and width. Compared to normal controls, obese/OSA ones showed similar directions of deformational changes, but the magnitude of change was two times larger in the tongue base and soft palate, and obese/OSA Panepinto minipigs presented 10 times larger changes in all dimensions of both the tongue base and the soft palate. The distance changes between the dorsal surface of tongue base and soft palate during inspiration increased in normal but decreased in obese OSA minipigs.

Respiratory internal kinematics of the tongue base and soft palate in obese minipigs with obstructive sleep apnea.

It is largely unknown how the tongue base and soft palate deform to alter the configuration of the oropharyngeal airway during respiration. This study is to address this important gap. After live sleep monitoring of 5 Yucatan and 2 Panepinto minipigs to verify obstructive sleep apnea (OSA), 8 and 4 ultrasonic crystals were implanted into the tongue base and soft palate to circumscribe a cubic and square region, respectively. The 3D and 2D dimensional changes of the circumscribed regions were measured simultaneously with electromyographic activity (EMG) of the oropharyngeal muscles during spontaneous respiration under sedated sleep. The results indicated that both obese Yucatan and Panepinto minipigs presented spontaneous OSA, but not in 3 non-obese Yucatan minipigs. During inspiration, the tongue base showed elongation in both dorsal and ventral regions but thinning and thickening in the anterior and posterior regions respectively. The widths showed opposite directions, widening in the dorsal but narrowing in the ventral regions. The soft palate expanded in both length and width. Compared to normal controls, obese/OSA ones showed similar directions of dimensional changes, but the magnitude of change was two times larger in the tongue base and soft palate, and obese/OSA Panepinto minipigs presented 10 times larger changes in all dimensions of both the tongue base and the soft palate. The opposite direction of the respiratory spatial relationship between these two structures was seen in obese/OSA as compared to normal minipigs.

Evaluation of the biocompatibility, antibacterial and anticancer effects of a novel nano-structured Fe-Mn-based biodegradable alloys in-vitro study.

Scientific backgrounds: Development of nanostructured biodegradable alloys has generated a great deal of interest in the recent years as they offer promising bioactive materials for reconstruction of bony defects following traumatic fractures or surgical excision of tumors. Objectives: The aim of the current study was to investigate the biocompatibility of Iron-Manganese -based alloys (Fe-Mn) with addition of copper (Cu), Tungsten (W) and cobalt (Co) to obtain 3 different alloys namely, Fe-Mn-Cu, Fe-Mn-W, and Fe-Mn-Co on normal oral epithelial cell line,and their possible anticancer effect on MG-63: osteosarcoma cell line. Materials and methods: The sulforhodamine B (SRB) assay was used to assess cell viability percentage of both cell lines after exposure to discs of the proposed experimental alloys. Moreover, the antibacterial effect of such alloys against Escherichia coli (E. coli) was tested using disc diffusion susceptibility (Kirby-Bauer method) and colony suspension method. Results: The cell viability percentage of oral epithelial cell line showed a significant increase in all the experimental groups in comparison to the control group. The highest percentage was observed in Fe-Mn-Co group, followed by Fe-Mn-W then Fe-Mn-Cu, at 24 and 72-h intervals, respectively. While the cell viability percentage of osteosarcoma cell line showed significant increase in all the experimental groups at 24-h intervals, it showed a significant drop in all the study groups at 72-h intervals. The lowest percentage was observed in Fe-Mn-Cu group, followed by Fe-Mn-W then Fe-Mn-Co. Moreover, all the examined study groups didn't show any inhibition zones against E. coli reference culture. Conclusions: The novel nanostructured biodegradable Fe-Mn-Cu, Fe-Mn-W, and Fe-Mn-Co metal alloys exhibit good biocompatibility on oral epithelial cell lines with the enhancement of cell proliferation in a time-dependent manner that favors bone regeneration. On the other hand, all the alloys manifested possible anticancer activity against MG-63: osteosarcoma cell line. Furthermore, our study sheds the light on the importance of Co, W and Cu as promising alloying elements. However, the antibacterial activity of the examined alloys is still questionable. Clinical relevance: The novel nanostructured biodegradable Fe-Mn-Cu, Fe-Mn-W, and Fe-Mn-Co metal alloys offer promising bioactive materials for reconstruction of bony defects following traumatic fractures or surgical excision of tumors, In addition, they could be excellent alternatives for undegradable or non-resorbable alloys that are commonly used. Moreover, they could be used as beneficial 3D printing materials to obtain patient-specific medical implants that favor bone regeneration in addition to manufacturing of plates and screws suitable for fracture fixation.