Bradykinesia and Its Progression Are Related to Interhemispheric Beta Coherence.

OBJECTIVE: Bradykinesia is the major cardinal motor sign of Parkinson disease (PD), but its neural underpinnings are unclear. The goal of this study was to examine whether changes in bradykinesia following long-term subthalamic nucleus (STN) deep brain stimulation (DBS) are linked to local STN beta (13-30 Hz) dynamics or a wider bilateral network dysfunction. METHODS: Twenty-one individuals with PD implanted with sensing neurostimulators (Activa® PC + S, Medtronic, PLC) in the STN participated in a longitudinal 'washout' therapy study every three to 6 months for an average of 3 years. At each visit, participants were withdrawn from medication (12/24/48 hours) and had DBS turned off (>60 minutes) before completing a repetitive wrist-flexion extension task, a validated quantitative assessment of bradykinesia, while local field potentials were recorded. Local STN beta dynamics were investigated via beta power and burst duration, while interhemispheric beta synchrony was assessed with STN-STN beta coherence. RESULTS: Higher interhemispheric STN beta coherence, but not contralateral beta power or burst duration, was significantly associated with worse bradykinesia. Bradykinesia worsened off therapy over time. Interhemispheric STN-STN beta coherence also increased over time, whereas beta power and burst duration remained stable. The observed change in bradykinesia was related to the change in interhemispheric beta coherence, with greater increases in synchrony associated with further worsening of bradykinesia. INTERPRETATION: Together, these findings implicate interhemispheric beta synchrony as a neural correlate of the progression of bradykinesia following chronic STN DBS. This could imply the existence of a pathological bilateral network contributing to bradykinesia in PD. ANN NEUROL 2023;93:1029-1039.

Ethical considerations for artificial intelligence in dermatology: a scoping review.

The field of dermatology is experiencing the rapid deployment of artificial intelligence (AI), from mobile applications (apps) for skin cancer detection to large language models like ChatGPT that can answer generalist or specialist questions about skin diagnoses. With these new applications, ethical concerns have emerged. In this scoping review, we aimed to identify the applications of AI to the field of dermatology and to understand their ethical implications. We used a multifaceted search approach, searching PubMed, MEDLINE, Cochrane Library and Google Scholar for primary literature, following the PRISMA Extension for Scoping Reviews guidance. Our advanced query included terms related to dermatology, AI and ethical considerations. Our search yielded 202 papers. After initial screening, 68 studies were included. Thirty-two were related to clinical image analysis and raised ethical concerns for misdiagnosis, data security, privacy violations and replacement of dermatologist jobs. Seventeen discussed limited skin of colour representation in datasets leading to potential misdiagnosis in the general population. Nine articles about teledermatology raised ethical concerns, including the exacerbation of health disparities, lack of standardized regulations, informed consent for AI use and privacy challenges. Seven addressed inaccuracies in the responses of large language models. Seven examined attitudes toward and trust in AI, with most patients requesting supplemental assessment by a physician to ensure reliability and accountability. Benefits of AI integration into clinical practice include increased patient access, improved clinical decision-making, efficiency and many others. However, safeguards must be put in place to ensure the ethical application of AI.

The use of artificial intelligence (AI) in dermatology is rapidly increasing, with applications in dermatopathology, medical dermatology, cutaneous surgery, microscopy/spectroscopy and the identification of prognostic biomarkers (characteristics that provide information on likely patient health outcomes). However, with the rise of AI in dermatology, ethical concerns have emerged. We reviewed the existing literature to identify applications of AI in the field of dermatology and understand the ethical implications. Our search initially identified 202 papers, and after we went through them (screening), 68 were included in our review. We found that ethical concerns are related to the use of AI in the areas of clinical image analysis, teledermatology, natural language processing models, privacy, skin of colour representation, and patient and provider attitudes toward AI. We identified nine ethical principles to facilitate the safe use of AI in dermatology. These ethical principles include fairness, inclusivity, transparency, accountability, security, privacy, reliability, informed consent and conflict of interest. Although there are many benefits of integrating AI into clinical practice, our findings highlight how safeguards must be put in place to reduce rising ethical concerns.

Part 1: Management of Antithrombotic Medications in Dermatologic Surgery.

Perioperative management of antithrombotic agents requires practical and medical considerations. Discontinuing antithrombotic therapies increases the risk of thrombotic adverse events including cerebrovascular accidents, myocardial infarction, pulmonary embolism, deep vein thrombosis, and retinal artery occlusion. Conversely, continuation of antithrombotic therapy during surgical procedures has associated bleeding risks. Currently, no guidelines exist regarding management of antithrombotic agents in the perioperative period for cutaneous surgeries and practice differs by surgeon. Here, we review the data on antithrombotic medications in patients undergoing cutaneous surgery including medication-specific surgical and postoperative bleeding risk if the medications are continued, and thromboembolic risk if the medications are interrupted. Specifically, we focus on vitamin K antagonist (VKA) (warfarin), direct-acting oral anticoagulants (DOAC) (rivaroxaban, apixaban, edoxaban, dabigatran), antiplatelet medications (aspirin, clopidogrel, prasugrel, ticagrelor, dipyridamole), unfractionated heparin, low molecular weight heparin (enoxaparin and dalteparin), fondaparinux, bruton tyrosine kinase inhibitors (BTKi) (ibrutinib, acalabrutinib), and dietary supplements (i.e., garlic, ginger, gingko).

Part 2: Management of Intraoperative and Perioperative Bleeding.

With an increase in number of patients on antithrombotic therapies, management of bleeding during dermatologic surgery is increasingly important. As described in Part 1, perioperative discontinuation of antithrombotic therapies may increase the risk of embolic events thus the risks and benefits must be weighed carefully when deciding whether to continue or suspend therapy. However, continuing oral anticoagulants may result in increased intraoperative and postoperative bleeding. Here we describe various methods to effectively achieve hemostasis which include: 1) mechanical methods to compress the vasculature 2) pharmacologic agents that induce vasoconstriction 3) physiologic agents that augment clot formation and 4) physical agents that promote platelet aggregation.

Genome-wide transcriptome analysis of the STAT6-regulated genes in advanced-stage cutaneous T-cell lymphoma.

The signal transducer and activator of transcription 6 (STAT6) is a critical up-stream mediator of interleukin-13 (IL-13) and IL-4 signaling and is constitutively activated in malignant lymphocytes from Sezary syndrome (SS) and mycosis fungoides (MF), the most common subtypes of cutaneous T-cell lymphomas. By combining genome-wide expression profiling with pharmacological STAT6 inhibition, we have identified the genes regulated by STAT6 in MF/SS tumors. We found that STAT6 regulates several common pathways in MF/SS malignant lymphocytes that are associated with control of cell-cycle progression and genomic stability as well as production of Th2 cytokines. Using ex vivo skin explants from cutaneous MF tumors as well as Sezary cells derived from the blood of SS patients, we demonstrated that inhibition of STAT6 activation downregulates cytokine production and induces cell-cycle arrest in MF/SS malignant lymphocytes, inhibiting their proliferation but not their survival. Furthermore, we show that STAT6 promotes the protumoral M2-like phenotype of tumor-associated macrophages in the tumor microenvironment of advanced stage MF by upregulating the expression of genes associated with immunosuppression, chemotaxis, and tumor matrix remodeling. Thus, we show STAT6 to be a major factor in the pathogenesis and progression of MF/SS, promoting proliferation and invasion of the malignant lymphocytes while inducing a progressive depression of the antitumor immune response. Together, our results provide new insights into disease pathogenesis and offer new prospective targets for therapeutic intervention.

Biomarkers in melanoma and non-melanoma skin cancer prevention and risk stratification.

The rates of melanoma and non-melanoma skin cancer (NMSC) have been increasing over the last twenty years in the United States, and this has been attributed to increased ultraviolet radiation exposure (UVR). Given these rising rates, preventative measures have become increasingly important to reduce the incidence and promote early detection of these cancers. Skin cancer prevention remains a challenging task to accomplish mainly due to the lack of reliable and sensitive methods to provide objective risk information that can educate and motivate individuals to avoid sunburn. Currently, minimal erythema dose (MED) is used as a marker of UVR. However, it is not an ideal marker because significant cancer-related molecular damage can occur after UVR exposure that cannot be detected by MED. Thus, over the recent years there has been significant interest in development of biomarkers indicative of exposure to UVR to improve early detection of cutaneous malignancies. Here, we will discuss emerging biomarkers for melanoma and NMSC that can help with risk stratification and targeted prevention and treatment.

UV biomarker genes for classification and risk stratification of cutaneous actinic keratoses and squamous cell carcinoma subtypes.

Currently, there is no sensitive molecular test for identifying transformation-prone actinic keratoses (AKs) and aggressive squamous cell carcinoma (SCC) subtypes. Biomarker-based molecular testing represents a promising tool for risk stratifying these lesions. We evaluated the utility of a panel of ultraviolet (UV) radiation-biomarker genes in distinguishing between benign and transformation-prone AKs and SCCs. The expression of the UV-biomarker genes in 31 SCC and normal skin (NS) pairs and 10 AK/NS pairs was quantified using the NanoString nCounter system. Biomarker testing models were built using logistic regression models with leave-one-out cross validation in the training set. The best model to classify AKs versus SCCs (area under curve (AUC) 0.814, precision score 0.833, recall 0.714) was constructed using a top-ranked set of 13 UV-biomarker genes. Another model based on a 15-gene panel was developed to differentiate histologically concerning from less concerning SCCs (AUC 1, precision score 1, recall 0.714). Finally, 12 of the UV-biomarker genes were differentially expressed between AKs and SCCs, while 10 genes were uniquely expressed in the more concerning SCCs. UV-biomarker gene subsets demonstrate dynamic utility as molecular tools to classify and risk stratify AK and SCC lesions, which will complement histopathologic diagnosis to guide treatment of high-risk patients.

CD8+ Lymphogranulomatous Dermatitis as a Manifestation of Malignancy-Associated Immunodeficiency: Rethinking Paraneoplastic Granulomas.

ABSTRACT: Paraneoplastic granulomatous disease occurs in approximately 7.3% of patients with non-Hodgkin lymphoma, most commonly among patients with chronic lymphocytic leukemia (CLL). These lesions are often reported to appear similar to sarcoidosis in clinical presentation and under light microscopy. However, comprehensive descriptions of the cytomorphologic characteristics of these paraneoplastic granulomas are lacking, and the mechanisms involved in their formation remain ill-defined. Noninfectious dermal granulomatous reactions have also been reported in many primary immunodeficiencies, including common variable immune deficiency and ataxia-telangiectasia. We present a case of noninfectious CD8+ predominant granulomatous dermatitis with ocular involvement occurring in the setting of CLL and marked hypogammaglobulinemia. Based on the analysis of shared factors in patients with primary immunodeficiencies and CLL, we conclude that the presence of pan-humoral immunodeficiency could itself be a risk factor for developing a CD8+ lymphogranulomatous reaction. This report and associated discussion evince that CD8+ predominant granulomatous reactions, distinct from sarcoidosis, may represent a previously unappreciated segment of the paraneoplastic granulomas observed in hematologic malignancies.

A Case Report of Papillary Digital Adenocarcinoma With BRAFV600E Mutation and Quantified Mutational Burden.

ABSTRACT: Papillary digital adenocarcinoma (PDA) is a rare eccrine tumor that is most often found on the digits. Few case reports have described PDAs located on atypical sites. It is now accepted that PDAs cannot be distinguished from benign adenomas based on histological features, and it is recommended to excise all of these lesions. Even with excision, recurrence and metastasis rates are high. Only limited genomic analyses have been performed to date, and no driver mutations have been identified. We report a case of a 63-year-old woman with a PDA on the right forearm. Biopsy showed moderate cytologic atypia and mitotic figures. Next-generation DNA sequencing of the tumor showed a BRAFV600E mutation and high tumor mutational burden (5.51 mutations/Mb). This mutation is known for its response to small molecular inhibitors of BRAF and Mitogen-activated protein kinase kinase. Such therapy may be a consideration should our patient develop recurrent unresectable disease.

Incidence estimates for lichen planopilaris and frontal fibrosing alopecia in a New York City health care system.

Lichen planopilaris (LPP) and frontal fibrosing alopecia (FFA) are scarring alopecias that cause significant distress and psychological morbidity. Limited studies have been performed examining the epidemiology of FFA and LPP. We performed a retrospective case cohort analysis by querying for patients with the ICD 10 code L66.1 (LPP, FFA) between 2015 and 2018 using the Clinical Data Warehouse (CDW) at NewYork-Presbyterian Hospital and Columbia Doctors. We calculated the one-year incidence of LPP/FFA between January 1, 2018 to December 31, 2018 by identifying all patients without a previously recorded ICD code for L66.1 who presented as a new hair loss patient based on chart review. A total of 170 patients were identified with a new diagnosis of LPP or FFA in 2018 among 1,187,583 patients. The standardized incidence per 100,000 was 12.75 for LPP and FFA combined, 7.35 for LPP alone, and 5.41 for FFA alone. The incidence peaked in the 51 to 60 age range (3.36). The incidence was highest in non-Hispanic White patients (17.27), White patients of unknown ethnicity (26.26), and non-Hispanic Asian patients (17.27). In New York City, LPP and FFA are uncommon diseases that are most common in middle-aged females and non-Hispanic White patients.

Biomarker function of HMGA2 in ultraviolet-induced skin cancer development.

The high mobility group AT-hook 2 (HMGA2) gene encodes a transcription factor that is expressed during embryonic development but down-regulated in adult tissues. Its re-expression in adult tissues is often associated with tumorigenesis. In this study, we found that HMGA2 is highly expressed in human cutaneous squamous cell carcinoma (SCC) cell lines and primary SCC tumors, but not in adjacent normal skin. In non-ultraviolet (UV)-irradiated mouse skin, baseline Hmga2 expression was detected in the epidermis but not in hair follicles. Following chronic UV exposure, we found activation of Hmga2 in hair follicles. UV-induced mouse skin SCC tumors displayed a ubiquitous increase in Hmga2 expression compared to non-tumor-bearing adjacent skin. In human SCC cells, decreased HMGA2 expression was linked with reduced cell proliferation following depletion of FOXM1 and TRIP13, two UV master regulator genes. Taken together, these findings highlight an important biomarker function of HMGA2 expression in UV-induced skin tumorigenesis and cell proliferation.

Oncolytic Viruses for the Treatment of Metastatic Melanoma.

OPINION STATEMENT: There is an unmet need for additional treatments for metastatic melanoma, besides anti-PD1 antibodies which are FDA approved for adjuvant therapy for stage III or resected stage IV melanoma. Talimogene laherparepvec (T-VEC) is the first and only FDA-approved oncolytic virus for the treatment of melanoma. New viral vectors including coxsackieviruses, HF-10, adenovirus, reovirus, echovirus, and newcastle disease virus are currently under active development and investigation with varying degrees of efficacy in targeting melanoma. The use of T-VEC as a neoadjuvant therapy is emerging, but more data is needed at this point. T-VEC has also shown promise for use in combination therapy with ipilimumab, as T-VEC plus ipilimumab has a significantly higher objective response compared to ipilimumab alone. Data comparing T-VEC in combination with PD-1 checkpoint inhibitors is awaited, and a phase III trial is underway. It is likely that oncolytic viruses will have long-term application in the treatment of melanoma and that T-VEC in particular will continue to have a role in the treatment of patients with readily accessible cutaneous lesions both for local control and synergistic induction of antitumor immunity as part of combination therapies.

Mogamulizumab-induced Mucocutaneous Lichenoid Reaction: A Case Report and Short Review.

is missing (Short communication).

Lupus Erythematosus Tumidus Mimicking Primary Cutaneous Marginal Zone B-cell Lymphoma.

is missing (Short communication).

Sixty-hertz stimulation improves bradykinesia and amplifies subthalamic low-frequency oscillations.

BACKGROUND: The objective of this study was to investigate the hypothesis that attenuation of subthalamic nucleus (STN) alpha-/beta-band oscillations is causal to improvement in bradykinesia. METHODS: STN local field potentials from a sensing neurostimulator (Activa® PC+S; Medtronic, Inc.) and kinematics from wearable sensors were recorded simultaneously during 60- and 140-Hz deep brain stimulation (DBS) in 9 freely moving PD subjects (15 STNs) performing repetitive wrist flexion-extension. Kinematics were recorded during 20-Hz DBS in a subgroup. RESULTS: Both 60- and 140-Hz DBS improved the angular velocity and frequency of movement (P = 0.002 and P = 0.029, respectively, for 60 Hz; P < 0.001 and P < 0.001, respectively, for 140 Hz), but 60-Hz DBS did not attenuate beta-band power (13-30 Hz). In fact, 60-Hz DBS amplified alpha/low-beta (11-15 Hz, P = 0.007) and attenuated high-beta power (19-27 Hz, P < 0.001), whereas 140-Hz DBS broadly attenuated beta power (15-30 Hz, P < 0.001). Only 60-Hz DBS improved the regularity of angular range (P = 0.046) and 20-Hz DBS did not worsen bradykinesia. There was no correlation between beta-power modulation and bradykinesia. CONCLUSIONS: These novel results obtained from freely moving PD subjects demonstrated that both 140- and 60-Hz DBS improved bradykinesia and attenuated high beta oscillations; however, 60-Hz DBS amplified a subband of alpha/low-beta oscillations, and DBS at a beta-band frequency did not worsen bradykinesia. Based on recent literature, we suggest that both 140- and 60-Hz DBS decouple the cortico-STN hyperdirect pathway, whereas 60-Hz DBS increases coupling within striato-STN circuitry. These results inform future algorithms for closed-loop DBS in PD. © 2016 International Parkinson and Movement Disorder Society.

Subthalamic beta oscillations are attenuated after withdrawal of chronic high frequency neurostimulation in Parkinson's disease.

Subthalamic nucleus (STN) local field potential (LFP) recordings demonstrate beta (13-30Hz) band oscillations in Parkinson's disease (PD) defined as elevations of spectral power. The amount of attenuation of beta band power on therapeutic levels of high frequency (HF) deep brain stimulation (DBS) and/or dopaminergic medication has been correlated with the degree of improvement in bradykinesia and rigidity from the therapy, which has led to the suggestion that elevated beta band power is a marker of PD motor disability. A fundamental question has not been answered: whether there is a prolonged attenuation of beta band power after withdrawal of chronic HF DBS and whether this is related to a lack of progression or even improvement in the underlying motor disability. Until now, in human PD subjects, STN LFP recordings were only attainable in the peri-operative period and after short periods of stimulation. For the first time, using an investigational, implanted sensing neurostimulator (Activa® PC+S, Medtronic, Inc.), STN LFPs and motor disability were recorded/assessed after withdrawal of chronic (6 and 12month) HF DBS in freely moving PD subjects. Beta band power was similar within 14s and 60min after stimulation was withdrawn, suggesting that "off therapy" experiments can be conducted almost immediately after stimulation is turned off. After withdrawal of 6 and 12months of STN DBS, beta band power was significantly lower (P<0.05 at 6 and 12months) and off therapy UPDRS scores were better (P<0.05 at 12months) compared to before DBS was started. The attenuation in beta band power was correlated with improvement in motor disability scores (P<0.05). These findings were supported by evidence of a gradual increase in beta band power in two unstimulated STNs after 24months and could not be explained by changes in lead impedance. This suggests that chronic HF DBS exerts long-term plasticity in the sensorimotor network, which may contribute to a lack of progression in underlying motor disability in PD.