Evaluation of risk factors, clinico-radiographic presentations of COVID-associated mucormycosis in the maxillofacial region reporting to a tertiary care dental facility.

Purpose: To evaluate the prevalence of risk factors associated with COVID-associated mucormycosis (CAM) in the maxillofacial region with emphasis on clinical and radiological characteristics of the disease reporting to the dentists. Methods: Archival records of the patients diagnosed with rhino-cerebral mucormycosis through histopathology or culture, were screened and 266 records were included. These records were divided into three groups-previously diabetic (PD, n = 122), recently diagnosed diabetic (RD, n = 105) and non-diabetic (ND, n = 39). All the records were evaluated and compared among the three groups for the duration of presentation, history of co-existing medical conditions, the association of treatment given during COVID-19, and the clinical and radiographic presentations of the disease. Results: The results confirmed uncontrolled diabetes mellitus as the major risk factor for the disease. The prevalence of steroid administration was lower in our study in contrast to previous literature. The risk factors and treatment rendered during COVID-19 did not differ significantly among the three groups (p > 0.05). The findings indicate that the disease was milder and progressed more slowly in the ND group, both clinically and radiographically, and it had close resemblance to odontogenic infection. Conclusion: Patients with early CAM mimicked the odontogenic infection and were more likely to report in a dental setup. Hence, a multidisciplinary and holistic management approach is necessary.

Evolution of modular and pleiotropic enhancers.

Cis-regulatory elements (CREs), or enhancers, are segments of noncoding DNA that regulate the spatial and temporal expression of nearby genes. Sometimes, genes are expressed in more than one tissue, and this can be driven by two main types of CREs: tissue-specific "modular" CREs, where different CREs drive expression of the gene in the different tissues, or by "pleiotropic" CREs, where the same CRE drives expression in the different tissues. In this perspective, we will discuss some of the ways (i) modular and pleiotropic CREs might originate; (ii) propose that modular CREs might derive from pleiotropic CREs via a process of duplication, degeneration, and complementation (the CRE-DDC model); and (iii) propose that hotspot loci of evolution are associated with the origin of modular CREs belonging to any gene in a regulatory network.

Display of individuality in avoidance behavior and risk assessment of inbred mice.

Factors determining individuality are still poorly understood. Rodents are excellent model organisms to study individuality, due to a rich behavioral repertoire and the availability of well-characterized isogenic populations. However, most current behavioral assays for rodents have short test duration in novel test environments and require human interference, which introduce coercion, thereby limiting the assessment of naturally occurring individuality. Thus, we developed an automated behavior system to longitudinally monitor conditioned fear for assessing PTSD-like behavior in individual mice. The system consists of a safe home compartment connected to a risk-prone test compartment (TC). Entry and exploration of the TC is solely based on deliberate choice determined by individual fear responsiveness and fear extinction. In this novel ethological assay, C57BL/6J mice show homogeneous responses after shock exposure (innate fear), but striking variation in long-lasting fear responses based on avoidance and risk assessment (learned fear), including automated stretch-attend posture quantification. TC entry (retention) latencies after foot shock differed >24 h and the re-explored TC area differed >50% among inbred mice. Next, we compared two closely related C57BL/6 substrains. Despite substantial individual differences, previously observed higher fear of C57BL/6N vs. C57BL/6J mice was reconfirmed, whereas fear extinction was fast and did not differ. The observed variation in fear expression in isogenic mice suggests individual differences in coping style with PTSD-like avoidance. Investigating the assumed epigenetic mechanisms, with reduced interpretational ambiguity and enhanced translational value in this assay, may help improve understanding of personality type-dependent susceptibility and resilience to neuropsychiatric disorders such as PTSD.