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Multimodal Imaging Directs Decision Making in Intraseptal L-AAOCA
No full textBackground: Congenital coronary artery abnormalities represent an uncommon class of congenital heart disease with an associated risk of sudden cardiac death. There is a paucity of data for the evaluation and management of affected patients with an intraseptal course.
Case summary: A 27-year-old woman was found to have a single coronary trunk arising from the right sinus with a 2.7 cm intraseptal course of the left main coronary artery. She underwent stress cardiac magnetic resonance and catheterization, to assess for inducible ischemia before surgical repair with transconal unroofing. Her recovery was uneventful, and she remains free of symptoms.
Discussion: Management of congenital coronary artery anomalies requires an exhaustive evaluation. Further studies are warranted to define the ideal work-up, indication, and timing of intervention and the efficacy of medical management in improving symptoms.
Take-home messages: Congenital coronary anomalies represent a rare but consequential cause of exertional chest pain. This diagnosis requires multimodal imaging to inform decision making
Utility of 3-Dimensional Echocardiography in Patients With Complex Intracardiac Connections and Ventricular Septal Defects
No full textThe surgical management of patients with complex intracardiac connections, ventricular septal defect (VSD), and 2 adequately sized ventricles is challenging. Understanding the VSD anatomy and its spatial relationships with the outflow tracts is critical to determining the suitability for biventricular repair. Transthoracic 2-dimensional echocardiography (2D-echo) is the primary cardiac imaging tool in congenital heart disease. Transthoracic 3-dimensional echocardiography (3D-echo) has an additive role over 2D-echo in the definition of the potential baffle pathway from the VSD to the semilunar valves, the anatomical characteristics of the VSD, and any substrate for systemic outflow tract obstruction postrepair. In this paper, we describe 4 cases where transthoracic 3D-echo provided crucial delineation of the intracardiac connections and the VSD anatomy for surgical planning. We also describe our transthoracic 3D-echo protocol to evaluate these complex heart defects
Nonexposed Endoscopic Full Thickness Resection of Residual Disease After Definitive Chemoradiation for Locally Advanced Gastric Cancer
No full textSalvage endoscopic resection of residual esophageal neoplasia for patients that prefer to avoid surgery or are poor surgical candidates has been reported. We report a case of gastric signet ring cell carcinoma with residual disease after definitive chemoradiotherapy, that was treated with nonexposed endoscopic full thickness resection. This endoscopic resection achieved negative margins, with postresection surveillance endoscopy and imaging showing no evidence of disease. This case highlights the potential use of salvage endoscopic resection as a therapy for residual gastric cancer after chemoradiation in patients where surgery is not an option
Unraveling the Hidden Complexity of Cancer Through Long-Read Sequencing
No full textCancer is fundamentally a disease of the genome, characterized by extensive genomic, transcriptomic, and epigenomic alterations. Most current studies predominantly use short-read sequencing, gene panels, or microarrays to explore these alterations; however, these technologies can systematically miss or misrepresent certain types of alterations, especially structural variants, complex rearrangements, and alterations within repetitive regions. Long-read sequencing is rapidly emerging as a transformative technology for cancer research by providing a comprehensive view across the genome, transcriptome, and epigenome, including the ability to detect alterations that previous technologies have overlooked. In this Perspective, we explore the current applications of long-read sequencing for both germline and somatic cancer analysis. We provide an overview of the computational methodologies tailored to long-read data and highlight key discoveries and resources within cancer genomics that were previously inaccessible with prior technologies. We also address future opportunities and persistent challenges, including the experimental and computational requirements needed to scale to larger sample sizes, the hurdles in sequencing and analyzing complex cancer genomes, and opportunities for leveraging machine learning and artificial intelligence technologies for cancer informatics. We further discuss how the telomere-to-telomere genome and the emerging human pangenome could enhance the resolution of cancer genome analysis, potentially revolutionizing early detection and disease monitoring in patients. Finally, we outline strategies for transitioning long-read sequencing from research applications to routine clinical practice
Deciphering the Dark Cancer Phosphoproteome Using Machine-Learned Co-Regulation of Phosphosites
No full textMass spectrometry-based phosphoproteomics offers a comprehensive view of protein phosphorylation, yet our limited knowledge about the regulation and function of most phosphosites hampers the extraction of meaningful biological insights. To address this challenge, we integrate machine learning with phosphoproteomic data from 1195 tumor specimens spanning 11 cancer types to construct CoPheeMap, a network that maps the co-regulation of 26,280 phosphosites. By incorporating network features from CoPheeMap into a second machine learning model, namely CoPheeKSA, we achieve superior performance in predicting kinase-substrate associations. CoPheeKSA uncovers 24,015 associations between 9399 phosphosites and 104 serine/threonine kinases, shedding light on many unannotated phosphosites and understudied kinases. We validate the accuracy of these predictions using experimentally determined kinase-substrate specificities. Through the application of CoPheeMap and CoPheeKSA to phosphosites with high computationally predicted functional significance and those associated with cancer, we demonstrate their effectiveness in systematically elucidating phosphosites of interest. These analyses unveil dysregulated signaling processes in human cancer and identify understudied kinases as potential therapeutic targets
Inhibition of ROS1 Activity With Lorlatinib Reversibly Suppresses Fertility in Male Mice
No full textBackground: Inhibition of sperm maturation in the epididymis is a promising post-testicular strategy for short-acting male contraceptives. It has been shown that ROS1, a receptor tyrosine kinase expressed in the epididymis, is essential for epididymal differentiation, sperm maturation, and male fertility in mice. However, it is unknown if inhibition of ROS1 suppresses male fertility reversibly.
Objectives: Our study aimed to investigate the effects of ROS1 inhibitor administration in male mice on sperm function and fertility.
Materials and methods: We used lorlatinib, an anti-cancer drug that inhibits ROS1. We treated 10-week-old sexually mature male mice with lorlatinib for 3 weeks and performed fertility tests, histological staining, in vitro fertilization, sperm motility analyses, and immunoblot analyses. We also performed the same analyses 3 weeks after discontinuing the lorlatinib treatment.
Results: Inhibition of ROS1 for 3 weeks suppressed male fertility. Lorlatinib-treated mice showed no overt abnormalities in testicular sections, but epithelium maintenance of the epididymal initial segment was impaired. Accordingly, the levels of OVCH2, RNASE10, and ADAM28, which are expressed in the epididymis, decreased. Spermatozoa from the lorlatinib-treated mice lost their ability to bind to the zona pellucida, and ADAM3 processing was abnormal. Sperm motility was also impaired in the lorlatinib-treated mice. These impairments were recovered 3 weeks after discontinuing the drug treatment.
Discussion and conclusion: Inhibition of ROS1 with lorlatinib suppressed sperm maturation and male fertility reversibly. Future exploration of molecules that specifically target ROS1 and the ROS1 pathway in the epididymis may lead to the development of safe and reversible male contraceptives
Deletion of Fibro-Adipogenic Progenitors-Specific Follistatin Impairs Muscle Function and Accelerates Skeletal Muscle Atrophy in Obese Mice
No full textBackground: Follistatin is a potent regulator of various TGF-β superfamily members, including myostatin (MSTN) and activin A. Previous studies have shown that follistatin is crucial in enhancing myogenesis during acute muscle injury. The mechanism by which fibro-adipogenic progenitors (FAPs)-specific follistatin influences muscle homeostasis in obese mice remains unknown. Therefore, we investigated the physiological role of follistatin in PDGFRα-positive FAPs in the regulation of muscle homeostasis and exercise in obese mice.
Methods: A PDGFRα-specific follistatin knockout (follistatin KO) mouse model was generated using PDGFRα-GFP-CreERT2 (PDGFRα-GCE) and follistatinflox/flox mice. These mice were fed a 60% high-fat diet (HFD) for 20 weeks, followed by a series of analyses, including exercise tolerance test, grip strength test, glucose and insulin tolerance assays, gene expression analysis, histology, western blotting, and immunohistochemistry.
Results: We showed that follistatin KO mice had reduced expression of Fst in skeletal muscle and white adipose tissue. We also showed that follistatin KO mice exhibited decreased exercise performance and altered skeletal homeostasis during obesity. Deletion of follistatin in FAPs activated the MSTN: Activin A/SMADs signaling pathways, which negatively impacted muscle homeostasis. Furthermore, follistatin KO mice showed reduced muscle mass, increased muscle degradation, and atrophic myofibers. Mitochondrial biogenesis, oxidative phosphorylation, and fatty acid oxidation were also altered in the skeletal muscles of follistatin KO mice.
Conclusion: Follistatin plays a protective role in mice by maintaining the metabolic health of skeletal muscles; it restores muscle function during HFD challenge, thereby reducing diet-induced obesity-related complications
Neonatal Seizures: Advances in Diagnosis and Management
No full textThe International League Against Epilepsy (ILAE) created the ILAE Neonatal Task Force that classified neonatal seizures, defined neonatal epilepsy syndromes, and specified treatment guidelines. These frameworks, in addition to improved access to genetic testing and other recent advances, have revolutionized the diagnosis and management of neonatal seizures. PLAIN LANGUAGE SUMMARY: Neonatal seizures, occurring within the first 4 weeks of life, present unique challenges due to the immature neonatal brain. The International League Against Epilepsy (ILAE) Neonatal Task Force revolutionized diagnosis and management through classification, syndrome definition, and treatment guidelines. Despite advancements, challenges persist, including accurate diagnosis and limited evidence-based treatment protocols, emphasizing the need for global efforts to standardize care
A Transdiagnostic, Multi-Modal Approach to Understanding Apathy: Methodological and Analytical Framework
No full textApathy is characterized by loss of motivation and manifests as a reduction of goal-directed behavior. Apathy is highly prevalent across neurodegenerative diseases, including Alzheimer\u27s Disease (AD) and Parkinson\u27s Disease (PD), and is an important contributor to the disability and reduce quality of life in these conditions. The treatment of apathy remains challenging due to a lack of specific therapies, largely attributed to an incomplete understanding of its cognitive and neuroanatomical underpinnings, crucial for developing targeted interventions. Apathy can be mechanistically studied through effort-based decision-making (EBDM) paradigms, where individuals choose between low- and high-effort tasks for varying reward magnitudes. Anatomically, apathy has been associated with alterations in brain regions previously implicated in EBDM. Using a novel transdiagnostic study design in individuals with AD and PD, we aim to: (1) evaluate the independent effects of reward and effort sensitivity as a mechanistic link between apathy and neurodegeneration of basal ganglia-frontal networks and, (2) in a subset of PD patients receiving deep brain stimulation (DBS) surgery, determine whether electrical manipulation of subthalamic nucleus and/or DBS connectivity, directly alter reward and effort information processing and, consequently, goal-directed behavior. Understanding how neurodegeneration-alone or in combination with neuromodulatory interventions-drives apathy, is essential for guiding clinical decision-making and therapeutic development. Given its prevalence across neurodegenerative disorders, apathy provides a unique framework for investigating shared and disease-specific neuroanatomical, functional, and behavioral mechanisms. In this protocol paper, we describe the rationale and methodology of our proposed multimodal approach, to investigate apathy in a transdiagnostic cohort of individuals with AD and PD
Multi-Ancestry Genome-Wide Meta-Analysis of 56,241 Individuals Identifies Known and Novel Cross-Population and Ancestry-Specific Associations as Novel Risk Loci for Alzheimer’s Disease
No full textBackground: Limited ancestral diversity has impaired our ability to detect risk variants more prevalent in ancestry groups of predominantly non-European ancestral background in genome-wide association studies (GWAS). We construct and analyze a multi-ancestry GWAS dataset in the Alzheimer\u27s Disease Genetics Consortium (ADGC) to test for novel shared and population-specific late-onset Alzheimer\u27s disease (LOAD) susceptibility loci and evaluate underlying genetic architecture in 37,382 non-Hispanic White (NHW), 6728 African American, 8899 Hispanic (HIS), and 3232 East Asian individuals, performing within ancestry fixed-effects meta-analysis followed by a cross-ancestry random-effects meta-analysis.
Results: We identify 13 loci with cross-population associations including known loci at/near CR1, BIN1, TREM2, CD2AP, PTK2B, CLU, SHARPIN, MS4A6A, PICALM, ABCA7, APOE, and two novel loci not previously reported at 11p12 (LRRC4C) and 12q24.13 (LHX5-AS1). We additionally identify three population-specific loci with genome-wide significance at/near PTPRK and GRB14 in HIS and KIAA0825 in NHW. Pathway analysis implicates multiple amyloid regulation pathways and the classical complement pathway. Genes at/near our novel loci have known roles in neuronal development (LRRC4C, LHX5-AS1, and PTPRK) and insulin receptor activity regulation (GRB14).
Conclusions: Using cross-population GWAS meta-analyses, we identify novel LOAD susceptibility loci in/near LRRC4C and LHX5-AS1, both with known roles in neuronal development, as well as several novel population-unique loci. Reflecting the power of diverse ancestry in GWAS, we detect the SHARPIN locus with only 13.7% of the sample size of the NHW GWAS study (n = 409,589) in which this locus was first observed. Continued expansion into larger multi-ancestry studies will provide even more power for further elucidating the genomics of late-onset Alzheimer\u27s disease