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Biophysical factors play a fundamental role in human embryonic development. Traditional in vitro models of organogenesis focused on the biochemical environment and did not consider the effects of mechanical forces on developing tissue. While most human tissue has a Young's modulus in the low kilopascal range, the standard cell culture substrate, plasma-treated polystyrene, has a Young's modulus of 3 gigapascals, making it 10,000–100,000 times stiffer than native tissues. Modern in vitro approaches attempt to recapitulate the biophysical niche of native organs and have yielded more clinically relevant models of human tissues. Since Clevers' conception of intestinal organoids in 2009, the field has expanded rapidly, generating stem-cell derived structures, which are transcriptionally similar to fetal tissues, for nearly every organ system in the human body. For this reason, we conjecture that organoids will make their first clinical impact in fetal regenerative medicine as the structures generated ex vivo will better match native fetal tissues. Moreover, autologously sourced transplanted tissues would be able to grow with the developing embryo in a dynamic, fetal environment. As organoid technologies evolve, the resultant tissues will approach the structure and function of adult human organs and may help bridge the gap between preclinical drug candidates and clinically approved therapeutics. In this review, we discuss roles of tissue stiffness, viscoelasticity, and shear forces in organ formation and disease development, suggesting that these physical parameters should be further integrated into organoid models to improve their physiological relevance and therapeutic applicability. It also points to the mechanotransductive Hippo-YAP/TAZ signaling pathway as a key player in the interplay between extracellular matrix stiffness, cellular mechanics, and biochemical pathways. We conclude by highlighting how frontiers in physics can be applied to biology, for example, how quantum entanglement may be applied to better predict spontaneous DNA mutations. In the future, contemporary physical theories may be leveraged to better understand seemingly stochastic events during organogenesis. [ABSTRACT FROM AUTHOR]

This article evaluates the availability of key information on independent rhinology/skull base surgery fellowship websites compared to the American Rhinologic Society (ARS) website. The study found that out of 37 identified programs, 34 had program-created fellowship websites. On average, program-created websites fulfilled 49.4% of the criteria, while the ARS website fulfilled 58.1%. Important information such as case volume, sample case logs, and graduate placements were inconsistently provided on both types of websites. The article suggests that including these criteria could help applicants make more informed decisions when applying for a fellowship in rhinology/skull base surgery. [Extracted from the article]

Objective: Investigate incidence and natural history of otologic and sinonasal disease associated with 22q11.2 deletion syndrome. Study Design: Case series. Setting: Tertiary care children's hospital. Methods: Charts from consecutive children born 2000 to 2018 with a diagnosis of 22q11.2 deletion, DiGeorge, or velocardiofacial syndrome based on the International Classification of Diseases (ICD)‐9 and ICD‐10 codes were reviewed. Otologic and rhinologic diagnoses and surgeries and immune and microbiologic laboratory findings were collected from the medical record. Results: After the exclusion of patients with no 22q11.2 deletion (n = 101), otologic care at an outside hospital (n = 59), and loss to follow‐up prior to 3 years of age (n = 22), 128 were included. Males comprised 80 (62.5%) patients, 115 (89.8%) were white, and the median age at genetic confirmation of 22q11.2 deletion was 119 days (range 0 days to 14.6 years). Recurrent acute otitis media (RAOM), chronic otitis media with effusion, chronic rhinosinusitis, and recurrent acute sinusitis were diagnosed in 54 (42.2%), 37 (28.9%), 10 (7.8%), and 8 (6.3%), respectively. Tympanostomy tubes were placed in 49 (38.3%). Adenoidectomy and sinus surgery were performed in 38 (29.7%) and 4 (3.1%), respectively. Neither immunoglobulin nor cluster of differentiation deficiency increased the odds of RAOM diagnosis, tympanostomy tube placement, or chronic/recurrent sinusitis. Methicillin‐resistant Staphylococcus aureus was the most common organism in sinus cultures (4/13, 30.8%). Streptococcus pneumonia dominated otorrhea cultures (11/21, 52.4%). Conclusion: Approximately half of children with 22q11.2 deletion may experience otologic disease that often requires surgical management. Future studies will utilize a larger cohort to examine the role of immunodeficiency in otologic and rhinologic disease in this population. [ABSTRACT FROM AUTHOR]

Extracellular signal-regulated kinase (ERK) is a member of the mitogen-activated protein kinase family of signaling molecules. ERK is predominantly found in two forms, ERK1 (p44) and ERK2 (p42), respectively. There are also several atypical forms of ERK, including ERK3, ERK4, ERK5 and ERK7. The ERK1/2 signaling pathway has been implicated in many and diverse cellular events, including proliferation, growth, differentiation, cell migration, cell survival, metabolism and transcription. ERK1/2 is activated (i.e., phosphorylated) in the cytosol and subsequently translocated to the nucleus, where it activates transcription factors including, but not limited to, ETS, c-Jun, and Fos. It is not surprising that the ERK1/2 signaling cascade has been implicated in many pathological conditions, namely, cancer, arthritis, chronic inflammation, and osteoporosis. This narrative review examines many of the cellular events in which the ERK1/2 signaling cascade plays a critical role. It is anticipated that agents designed to inhibit ERK1/2 activation or p-ERK1/2 activity will be developed for the treatment of those diseases characterized by dysregulated gene expression through ERK1/2 activation. [ABSTRACT FROM AUTHOR]