The nasal valves are not simple, 2-dimensional cross-sections but rather a complex, 3-dimensional, collapsible, and heterogeneous structure. Historically, the internal nasal valve (INV) is defined by the septum medially, the caudal margin of the upper lateral cartilage laterally, and the inferior turbinate inferiorly. Typically located 1.3 cm deep into the nasal cavity, the INV angle delineated by the upper lateral cartilage and septum typically measures 10° to 15° in the Caucasian population. As computational methods reveal new insights into nasal valve function, a new conceptual framework is needed to guide rhinoplasty surgical decision-making.
Understanding bacterial physiology in real-world environments requires noninvasive approaches and is a challenging yet necessary endeavor to effectively treat infectious disease. Bacteria evolve strategies to tolerate chemical gradients associated with infections. The DIVER (Deep Imaging Via Enhanced Recovery) microscope can image autofluorescence and fluorescence lifetime throughout samples with high optical scattering, enabling the study of naturally formed chemical gradients throughout intact biofilms. Using the DIVER, a long fluorescent lifetime signal associated with reduced pyocyanin, a molecule for electron cycling in low oxygen, was detected in low-oxygen conditions at the surface of Pseudomonas aeruginosa biofilms and in the presence of fermentation metabolites from Rothia mucilaginosa, which cocolonizes infected airways with P. aeruginosa. These findings underscore the utility of the DIVER microscope and fluorescent lifetime for noninvasive studies of bacterial physiology within complex environments, which could inform on more effective strategies for managing chronic infection.
Cerebral microhemorrhages (CMH) are the pathological substrate for MRI-demonstrable cerebral microbleeds, which are associated with cognitive impairment and stroke. Aging and hypertension are the main risk factors for CMH. In this study, we investigated the development of CMH in a mouse model of aging and hypertension. Hypertension was induced in aged (17-month-old) female and male C57BL/6J mice via angiotensin II (Ang II), a potent vasoconstrictor. We investigated the vascular origin of CMH using three-dimensional images of 1-mm thick brain sections. We examined Ang II-induced CMH formation with and without telmisartan, an Ang II type 1 receptor (AT1R) blocker. To evaluate the effect of microglia and perivascular macrophages on CMH formation, mice were treated with PLX3397, a selective colony-stimulating factor 1 receptor (CSF1R) inhibitor, to achieve microglial and macrophage depletion. Iba-1 and CD206 labeling were used to study the relative contributions of microglia and macrophages, respectively, on CMH formation. CMH quantification was performed with analysis of histological sections labeled with Prussian blue. Vessels surrounding CMH were primarily of capillary size range (< 10 μm in diameter). Ang II-infused mice exhibited elevated blood pressure (p < 0.0001) and CMH burden (p < 0.001). CMH burden was significantly correlated with mean arterial pressure in mice with and without Ang II (r = 0.52, p < 0.05). Ang II infusion significantly increased Iba-1 immunoreactivity (p < 0.0001), and CMH burden was significantly correlated with Iba-1 in mice with and without Ang II (r = 0.32, p < 0.05). Telmisartan prevented elevation of blood pressure due to Ang II infusion and blocked Ang II-induced CMH formation without affecting Iba-1 immunoreactivity. PLX3397 treatment reduced Iba-1 immunoreactivity in Ang II-infused mice (p < 0.001) and blocked Ang II-induced CMH (p < 0.0001). No significant association between CMH burden and CD206 reactivity was observed. Our findings demonstrate Ang II infusion increases CMH burden. CMH in this model appear to be capillary-derived and Ang II-induced CMH are largely mediated by blood pressure. In addition, microglial activation may represent an alternate pathway for CMH formation. These observations emphasize the continuing importance of blood pressure control and the role of microglia in hemorrhagic cerebral microvascular disease.
Background/Objectives: Cilia are hair-like organelles with various mechanosensory and chemosensory functions. In particular, motile cilia generate directional fluid flow important for multiple processes. Motile ciliopathies have serious clinical implications, including developmental and respiratory disorders. Evaluating the most suitable imaging methods for studying ciliary structure and function has great clinical significance. Methods: Here, we provide an overview of ciliary function, imaging modalities, and applications in ciliopathic diseases. Results: Optical imaging has become a crucial tool for studying ciliary structure and function, providing high-resolution, non-invasive imaging capabilities that are valuable for in vivo applications. Optical coherence tomography (OCT) is well suited for the visualization of ciliary anatomy and quantitative studies of microfluidic flow. Conclusions: A deeper understanding of ciliary biology can lead to novel approaches in diagnosing, treating, and monitoring ciliopathies, contributing to more effective and individualized care.
Confocal microscopy is an important bio-imaging technique that increases the resolution using a spatial pinhole to block out-of-focus light. In theory, the maximum resolution and optical sectioning are obtained when the detection pinhole is fully closed, but this is prevented by the dramatic decrease in the signal reaching the detector. In image scanning microscopy (ISM) this limitation is overcome by the use of an array of point detectors rather than a single detector. This, combined with pixel reassignment, increases the resolution of 2 over widefield imaging, with relatively little modification to the existing hardware of a laser-scanning microscope. Separation of photons by lifetime tuning (SPLIT) is a super-resolution technique, based on the phasor analysis of the fluorescent signal into an additional channel of the microscope. Here, we use SPLIT to analyze the information encoded within the array detectors distance for improving the resolution of ISM (SPLIT-ISM). We find that the lateral resolution can be increased of an additional 1.3 × with respect to the pixel-reassigned image with a concomitant increase in optical sectioning. We applied the SPLIT-ISM technique on biological images acquired by two currently available ISM systems: the Genoa Instruments PRISM and the Zeiss Airyscan. We evaluate the improvement provided by SPLIT-ISM through the QuICS algorithm, a quantitative tool based on image correlation spectroscopy. QuICS allows extracting three parameters related to the resolution, and contrast SNR of the image. We find that SPLIT-ISM provides an increase in spatial resolution for both the Genoa Instrument PRISM and the Zeiss Airyscan microscopes.
We introduce the feature issue of Optical Materials Express on Nonlinear Nanophotonics. This collection highlights recent advances in the design, fabrication, and application of nanophotonic systems that exploit nonlinear optical phenomena, spanning topics from high-harmonic generation and soliton microcombs to plasmon-enhanced emission and mid-infrared nonlinear optics.
Immunotherapy utilizing immune checkpoint inhibitors (ICIs) such as PD-1, PD-L1, and CTLA-4 inhibitors has revolutionized cancer therapy by enhancing T cell recognition and attack against cancer cells.1 Immune-related adverse events (irAEs) are a limitation of ICI therapy, encompassing various manifestations such as colitis and cutaneous adverse events such as dermatitis, alopecia, and vitiligo.2 Hair loss is a common concern of cancer patients as they embark on their therapeutic paths. The evidence on alopecia from isolated clinical trials with ICI therapies is limited and largely lacks diagnostic and prognostic details to help guide patients.3,4 In this systematic review, we examined the types of alopecia as part of the irAEs of ICI therapy, timing of onset, prognosis, and treatment approaches. Our analysis includes 19 studies describing new-onset non-scarring or scarring alopecia following ICI treatment. Alopecia was a rare adverse event in the setting of ICIs (n=26) with the onset of alopecia occurring within one year of initiating treatment. Slightly over half of the affected patients reported some degree of hair regrowth after attempted alopecia-directed treatments. We discuss available data to increase awareness of this rare but potentially permanent side effect of ICI therapy. Further research is warranted to enhance our understanding of alopecia as an irAE and to optimize patient management strategies. J Drugs Dermatol. 2025;24(3):255-260. doi:10.36849/JDD.7828.
