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Pancreatic in vitro research is of major importance to advance mechanistic understanding and development of treatment options for diseases such as diabetes mellitus. We present a thermoplastic-based microphysiological system aiming to model the complex microphysiological structure and function of the endocrine pancreas with concurrent real-time read-out capabilities. The specifically tailored platform enables self-guided trapping of single islets at defined locations: β-cells are assembled to pseudo-islets and injected into the tissue chamber using hydrostatic pressure-driven flow. The pseudo-islets can further be embedded in an ECM-like hydrogel mimicking the native microenvironment of pancreatic islets in vivo. Non-invasive real-time monitoring of the oxygen levels on-chip is realized by the integration of luminescence-based optical sensors to the platform. To monitor insulin secretion kinetics in response to glucose stimulation in a time-resolved manner, an automated cycling of different glucose conditions is implemented. The model's response to glucose stimulation can be monitored via offline analysis of insulin secretion and via specific changes in oxygen consumption due to higher metabolic activity of pseudo-islets at high glucose levels. To demonstrate applicability for drug testing, the effects of antidiabetic medications are assessed and changes in dynamic insulin secretion are observed in line with the respective mechanism of action. Finally, by integrating human pancreatic islet microtissues, we highlight the flexibility of the platform and demonstrate the preservation of long-term functionality of human endocrine pancreatic tissue. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to investigate the relationship between anatomical variations and the fungus ball (FB), and the association between odontogenic etiologies and the maxillary sinus FB. Methods: We analyzed the clinical records of 66 patients who underwent endoscopic sinus surgery for FB. The anatomical variations determined were nasal septal deviation (NSD) and direction, presence of Onodi and Haller cell, concha bullosa and lateral recess of the sphenoid sinus. Further, dental X-ray records were reviewed to detect any possible odontogenic etiologies in patients with maxillary sinus FBs. Results: There were 41 female and 25 male patients. Positive fungal culture was found in 60 patients (91%) and the causative fungus was Aspergillus species in all cases. The correlation between NSD and localization of the maxillary sinus FB was statistically significant (p=0.0409). Maxillary sinus FB was more common on the concave side of the NSD. Presence of dental pathologies was significantly associated with maxillary sinus FB compared to the healthy side (p=0.0011). For sphenoid sinus FB, NSD was detected in a similar number for both the affected and unaffected side and there were no significant correlations (p>0.05). However, the relationship between sphenoid sinus FB and presence of lateral recess was significant (p=0.0262). Conclusion: Our study revealed that the maxillary sinus FB was more common on the concave side of the deviated septum. Also, dental pathologies or a presence of dental treatment history were associated with maxillary sinus FB. [ABSTRACT FROM AUTHOR]