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Subcallosal cingulate (SCC) deep brain stimulation (DBS) is an emerging therapy for refractory depression. Good clinical outcomes are associated with the activation of white matter adjacent to the SCC. This activation produces a signature cortical evoked potential (EP), but it is unclear which of the many pathways in the vicinity of SCC is responsible for driving this response. Individualized biophysical models were built to achieve selective engagement of two target bundles: either the forceps minor (FM) or cingulum bundle (CB). Unilateral 2 Hz stimulation was performed in seven patients with treatment-resistant depression who responded to SCC DBS, and EPs were recorded using 256-sensor scalp electroencephalography. Two distinct EPs were observed: a 120 ms symmetric response spanning both hemispheres and a 60 ms asymmetrical EP. Activation of FM correlated with the symmetrical EPs, while activation of CB was correlated with the asymmetrical EPs. These results support prior model predictions that these two pathways are predominantly activated by clinical SCC DBS and provide first evidence of a link between cortical EPs and selective fiber bundle activation. [ABSTRACT FROM AUTHOR]

This article, published in the Journal of Neurological Surgery, explores the use of machine learning and 3D MRI-based analysis to predict the pathologic grade of skull base meningiomas. The study analyzed preoperative MRIs from 38 patients and used a custom machine learning pipeline to predict the grade of the tumor. The results showed that the machine learning model had an area under the receiver operating characteristic curve (AUROC) of 0.75, indicating its potential for predicting the pathologic grade. However, further research with a larger sample size is needed to validate these findings and improve prognostication for patients with skull base meningiomas. [Extracted from the article]

This article discusses the development of a new technology called "TumorID" that uses machine learning and noncontact fluorescence spectroscopy to analyze meningioma tissue in real-time during surgery. The aim of this technology is to differentiate between Grade 1 and Grade 2 meningiomas, which have different prognostic and management implications. The study found that the multi-layer perceptron and logistic regression models performed the best in predicting the grade of meningiomas, with high accuracy. However, further research is needed to validate these findings on larger sample sizes. The authors hope that this technology will eventually improve the efficiency and accuracy of prognostication for patients with meningiomas. [Extracted from the article]

The article discusses the use of ChatGPT, a language model developed for rapid use by the lay audience, in providing accurate medical information for the treatment of lumbar disc herniation with radiculopathy. The study found that both ChatGPT-3.5 and ChatGPT-4.0 provided accurate responses to just over 50% of questions, with nearly half of the responses being overconclusive. The models also provided supplemental information but were noted to have provided incomplete responses to some questions. The article highlights the limitations of using a general language model like ChatGPT for patient care and suggests ways to mitigate the model's inaccuracies and biases. [Extracted from the article]

Despite more than six decades of extensive research, the etiology of moyamoya disease (MMD) remains unknown. Inflammatory or autoimmune (AI) processes have been suggested to instigate or exacerbate the condition, but the data remains mixed. The objective of the present systematic review was to summarize the available literature investigating the association of MMD and AI conditions as a means of highlighting potential treatment strategies for this subset of moyamoya patients. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the PubMed, Embase, Scopus, Web of Science, and Cochrane databases were queried to identify studies describing patients with concurrent diagnoses of MMD and AI disease. Data were extracted on patient demographics, clinical outcomes, and treatment. Stable or improved symptoms were considered favorable outcomes, while worsening symptoms and death were considered unfavorable. Quantitative pooled analysis was performed with individual patient-level data. Of 739 unique studies identified, 103 comprising 205 unique patients (80.2% female) were included in the pooled analysis. Most patients (75.8%) identified as Asian/Pacific Islanders, and the most commonly reported AI condition was Graves' disease (57.6%), with 55.9% of these patients presenting in a thyrotoxic state. Of the 148 patients who presented with stroke, 88.5% of cases (n = 131) were ischemic. Outcomes data was available in 152 cases. There were no significant baseline differences between patients treated with supportive therapy alone and those receiving targeted immunosuppressant therapy. Univariable logistic regression showed that surgery plus medical therapy was more likely than medical therapy alone to result in a favorable outcome. On subanalysis of operated patients, 94.1% of patients who underwent combined direct and indirect bypass reported favorable outcomes, relative to 76.2% of patients who underwent indirect bypass and 82% who underwent direct bypass (p < 0.05). On univariable analysis, the presence of multiple AI disorders was associated with worse outcomes relative to having a single AI disorder. Autoimmune diseases have been uncommonly reported in patients with MMD, but the presence of multiple AI comorbidities portends poorer prognosis. The addition of surgical intervention appears to improve outcomes and for patients deemed surgical candidates, combined direct and indirect bypass appears to offer better outcomes that direct or indirect bypass alone. [ABSTRACT FROM AUTHOR]

Femoropopliteal artery (FPA) mechanics play a paramount role in pathophysiology and the artery's response to therapeutic interventions, but data on FPA mechanical properties are scarce. Our goal was to characterize human FPAs over a wide population to derive a constitutive description of FPA aging to be used for computational modeling. Fresh human FPA specimens ( $$n=579$$ ) were obtained from $$n=351$$ predominantly male (80 %) donors 54±15 years old (range 13-82 years). Morphometric characteristics including radius, wall thickness, opening angle, and longitudinal pre-stretch were recorded. Arteries were subjected to multi-ratio planar biaxial extension to determine constitutive parameters for an invariant-based model accounting for the passive contributions of ground substance, elastin, collagen, and smooth muscle. Nonparametric bootstrapping was used to determine unique sets of material parameters that were used to derive age-group-specific characteristics. Physiologic stress-stretch state was calculated to capture changes with aging. Morphometric and constitutive parameters were derived for seven age groups. Vessel radius, wall thickness, and circumferential opening angle increased with aging, while longitudinal pre-stretch decreased ( $$p<0.01$$ ). Age-group-specific constitutive parameters portrayed orthotropic FPA stiffening, especially in the longitudinal direction. Structural changes in artery wall elastin were associated with reduction of physiologic longitudinal and circumferential stretches and stresses with age. These data and the constitutive description of FPA aging shed new light on our understanding of peripheral arterial disease pathophysiology and arterial aging. Application of this knowledge might improve patient selection for specific treatment modalities in personalized, precision medicine algorithms and could assist in device development for treatment of peripheral artery disease. [ABSTRACT FROM AUTHOR]

Background: Although the study of calcium (Ca2+) is classically associated with excitable cells such as myocytes or neurons, the ubiquity of this essential element in all cellular processes has led to interest in other cell types. The importance of Ca2+ to apoptosis, cell signaling, and immune activation is of special import in cancer. Main: Here we review the current understanding of Ca2+ in each of these processes vital to the initiation, spread, and drug resistance of malignancies. We describe the involvement of Ca2+, and Ca2+ related proteins in cell cycle checkpoints and Ca2+ dependent apoptosis and discuss their roles in cellular immortalization. The role of Ca2+ in inter-cellular communication is also discussed in relevance to tumor-stromal communication, angiogenesis, and tumor microinvasion. The role that Ca2+ plays in immune surveillance and evasion is also addressed. Finally, we discuss the possibility of targeting Ca2+ singling to address the most pressing topics of cancer treatment: metastatic disease and drug resistance. Conclusion: This review discusses the current understanding of Ca2+ in cancer. By addressing Ca2+ facilitated angiogenesis, immune evasion, metastasis, and drug resistance, we anticipate future avenues for development of Ca2+ as a nexus of therapy. [ABSTRACT FROM AUTHOR]