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Classic polyarteritis nodosa (PAN) is an uncommon form of aggressive systemic vasculitis involving small-to-medium sized arteries usually of renal vasculature and other visceral organs but characteristically sparing the lung vasculature. Cutaneous PAN (c-PAN) is still a rare type of small-to-medium vessel vasculitis with involvement of skin without any systemic or visceral involvement. However, extracutaneous features such as arthritis, arthralgia, myopathy, and myositis can co-exist with the cutaneous features. c-PAN can be confirmed histopathologically by the presence of polymorphonuclear leukocytes around the medium-sized vessels with evidence of fibrinoid necrosis and luminal thrombi at the bifurcations. While c-PAN has a benign but chronic course and can be managed with low doses of short-course oral steroids or anti-inflammatory drugs, systemic involvement has an aggressive course and needs adequate and prompt immunosuppression with high dose oral steroids, cyclophosphamide, rituximab, or other immunosuppressive. We present a case of a 33-year-old male who landed in our OPD with features of c-PAN and on further investigative workup was found to have a renal infarct. [ABSTRACT FROM AUTHOR]

As artificial intelligence (AI) has been highly advancing in the last decade, machine learning (ML)-enabled medical devices are increasingly used in healthcare. In this study, we collected publicly available information on AI/ML-enabled medical devices approved by the FDA in the United States, as of the latest update on 19 October 2023. We performed comprehensive analysis of a total of 691 FDA-approved artificial intelligence and machine learning (AI/ML)-enabled medical devices and offer an in-depth analysis of clearance pathways, approval timeline, regulation type, medical specialty, decision type, recall history, etc. We found a significant surge in approvals since 2018, with clear dominance of the radiology specialty in the application of machine learning tools, attributed to the abundant data from routine clinical data. The study also reveals a reliance on the 510(k)-clearance pathway, emphasizing its basis on substantial equivalence and often bypassing the need for new clinical trials. Also, it notes an underrepresentation of pediatric-focused devices and trials, suggesting an opportunity for expansion in this demographic. Moreover, the geographical limitation of clinical trials, primarily within the United States, points to a need for more globally inclusive trials to encompass diverse patient demographics. This analysis not only maps the current landscape of AI/ML-enabled medical devices but also pinpoints trends, potential gaps, and areas for future exploration, clinical trial practices, and regulatory approaches. In conclusion, our analysis sheds light on the current state of FDA-approved AI/ML-enabled medical devices and prevailing trends, contributing to a wider comprehension. [ABSTRACT FROM AUTHOR]

Background: Melasma is a common acquired pigmentary disorder that is aesthetically displeasing. Kligman's and Modified Kligman's formula using topical steroids, hydroquinone and retinoids, and various other depigmenting agents is being widely used all over for melasma with varying results. Chemical peeling is newly added to the therapeutic armamentarium and is showing encouraging results worldwide in patients with melasma. However, comparative studies are lacking in abundance in our part of the world. Aims and Objectives: To determine if serial trichloroacetic acid peels provide additional benefits when combined with time-tested topical therapy with hydroquinone 4% in patients with melasma. Materials and Methods: Fifty melasma patients were divided into two groups of 25 each. One group received serial trichloroacetic acid peel combined with topical hydroquinone 4%. The other group only received topical hydroquinone 4% cream. The results were evaluated by a clinical investigator both subjectively and with photographs taken at baseline, 12 weeks, and 21 weeks. For clinical evaluation, the melasma area and severity index (MASI) was used. Results: A significant decrease in MASI score from baseline to 21 weeks was observed in both groups (P<0.001). The group receiving the trichloroacetic acid peel 20% showed a trend toward more rapid and greater improvement, with statistically significant results (P<0.001). Only a few side effects were observed in the peel group. Conclusion: This study demonstrates that serial trichloroacetic acid peels provide an additional effect to a topical regimen of 4% hydroquinone cream for treating melasma in Fitzpatrick skin types III and above if used judiciously and under supervision. It demonstrates that superficial chemical peels can be used as an adjunct with better efficacy to treat patients with melasma. [ABSTRACT FROM AUTHOR]

Background: Lichen planus(LP) is a unique common inflammatory disorder that is clinically characterized by violaceous pruritic flat polygonal papules or plaques. Recently, an association between LP and diabetes mellitus has been viewed with greater interest. Several studies done in assessing the association between these show conflicting results. Aims and Objectives: The aim of this study was to find an association between LP and diabetes mellitus. Materials and Methods: A cross-sectional comparative study was conducted in the Outpatient Department (OPD) of Dermatology, Bir Hospital. Any patient presenting at dermatology OPD above 16 years of age with LP were taken as cases. Age- and gendermatched patients with skin disease other than LP were taken as controls. The test was done by collecting 2ml of blood and serum HbA1c level was assessed allowing the blood to stand in a cuvette for 5 min inside the Erba Mannheim XL-300 analyzer to interact with DS5 reagent. The result was interpreted as per the calibration in the printed chromatogram. Results: Male preponderance with a male: female ratio of 1.08:1 was found in this study. The mean age of onset of LP was earlier in male 40.11 years than in female 44.66 years. Likewise, hypertrophic(30%) followed by eruptive(27.5%) wasthe most common variants of LP found in this study. Diabetes was more common in males(75%) with LP than in females(25%) with LP. Patients having longer duration of LP were more commonly associated with diabetes mellitus. Among clinical variants of LP, diabetes was associated more with eruptive variant followed by classic and hypertrophic variants. The prevalence of diabetes was higher in case(16%) than in control(4%),P=0.046. Conclusion: This study showed an association of LP with diabetes mellitus, the association being statistically significant(P=0.046). It, therefore, is desirable to do HbA1c level screening in patients with LP for timely detection of diabetes mellitus. [ABSTRACT FROM AUTHOR]

We study the effect of structured higher-order interactions on the collective behavior of coupled phase oscillators. By combining a hypergraph generative model with dimensionality reduction techniques, we obtain a reduced system of differential equations for the system's order parameters. We illustrate our framework with the example of a hypergraph with hyperedges of sizes 2 (links) and 3 (triangles). For this case, we obtain a set of two coupled nonlinear algebraic equations for the order parameters. For strong values of coupling via triangles, the system exhibits bistability and explosive synchronization transitions. We find conditions that lead to bistability in terms of hypergraph properties and validate our predictions with numerical simulations. Our results provide a general framework to study the synchronization of phase oscillators in hypergraphs, and they can be extended to hypergraphs with hyperedges of arbitrary sizes, dynamic-structural correlations, and other features.

We study synchronization dynamics in populations of coupled phase oscillators with higher-order interactions and community structure. We find that the combination of these two properties gives rise to a number of states unsupported by either higher-order interactions or community structure alone, including synchronized states with communities organized into clusters in-phase, anti-phase, and a novel skew-phase, as well as an incoherent-synchronized state. Moreover, the system displays strong multistability with many of these states stable at the same time. We demonstrate our findings by deriving the low dimensional dynamics of the system and examining the system's bifurcations using stability analysis and perturbation theory.