Publications by authors named "Bollen A"

Article Synopsis
  • Glioblastoma, despite treatment advancements, has a poor prognosis with less than 2 years median survival due to the unknown reasons for varied treatment responses.
  • A study analyzed glioblastoma samples from 106 patients, identifying early genetic changes like TERT promoter mutations, while later alterations varied between initial and recurrent tumors, along with diverse epigenetic changes impacting treatment outcomes.
  • Findings indicated that patients with somatic hypermutation post-treatment had better survival rates, and an epigenomic signature linked to DNA methylation changes could predict clinical results, emphasizing the complex evolution of this cancer.
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  • Metastatic Pituitary neuroendocrine tumors (PitNET) are rare and aggressive, making them difficult to treat; however, aggressive behavior is also observed in non-metastatic forms.
  • A study at UCSF analyzed samples from multiple patients with different types of aggressive PitNETs, categorizing them according to international neuroendocrine neoplasm criteria and identifying various tumor lineages.
  • High rates of disease progression and mortality were noted, along with concerning histopathological and molecular characteristics that could serve as indicators of tumor aggressiveness, suggesting a need for a new grading system.
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Introduction: This study used digital intraoral scans to evaluate how clear aligner treatment affects occlusal contacts and to determine the influence of sex and age on contact changes. Results were compared with contact changes that occur during fixed appliance therapy.

Methods: Patients included in this study were treated in a University setting and private practice.

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Article Synopsis
  • Glioblastoma is a diverse disease, and researchers found a rare subgroup (2%) with unique genetic traits that could help predict treatment responses.
  • These tumors have specific mutations linked to Lynch syndrome, appear at a younger median age (50 years), and differ significantly from conventional glioblastomas in genetic and histological characteristics.
  • Patients from this subgroup showed an impressive median overall survival of 36.8 months when treated with immune checkpoint inhibitors, highlighting the potential for targeted therapies.
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Introduction: Little is known about how precisely orthodontists in the United States (US) assess crowding or at what range of crowding they recommend extraction. This study aimed to assess the relationship between estimated crowding in patients with a Class I relationship and extraction recommendation by orthodontists in the US. The secondary aims were to evaluate the accuracy and precision of clinician estimations and determine if clinician background traits play a role in extraction decision-making.

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Background: Schwannomas are common peripheral nerve sheath tumors that can cause severe morbidity given their stereotypic intracranial and paraspinal locations. Similar to many solid tumors, schwannomas and other nerve sheath tumors are primarily thought to arise due to aberrant hyperactivation of the RAS growth factor signaling pathway. Here, we sought to further define the molecular pathogenesis of schwannomas.

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Article Synopsis
  • - A patient in California survived a rare and often fatal infection called Balamuthia mandrillaris granulomatous amebic encephalitis after receiving a new treatment approach.
  • - The treatment included nitroxoline, a drug originally developed for urinary tract infections, which was found to have effectiveness against the ameba.
  • - Researchers identified nitroxoline through a screening process aimed at finding drugs that can kill Balamuthia, showcasing the potential for repurposing existing medications.
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Upregulation of Notch signaling is associated with brain arteriovenous malformation (bAVM), a disease that lacks pharmacological treatments. Tetracycline (tet)-regulatable endothelial expression of constitutively active Notch4 (Notch4*tetEC) from birth induced bAVMs in 100% of mice by P16. To test whether targeting downstream signaling, while sustaining the causal Notch4*tetEC expression, induces AVM normalization, we deleted Rbpj, a mediator of Notch signaling, in endothelium from P16, by combining tet-repressible Notch4*tetEC with tamoxifen-inducible Rbpj deletion.

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Gliomas arising in the setting of neurofibromatosis type 1 (NF1) are heterogeneous, occurring from childhood through adulthood, can be histologically low-grade or high-grade, and follow an indolent or aggressive clinical course. Comprehensive profiling of genetic alterations beyond NF1 inactivation and epigenetic classification of these tumors remain limited. Through next-generation sequencing, copy number analysis, and DNA methylation profiling of gliomas from 47 NF1 patients, we identified 2 molecular subgroups of NF1-associated gliomas.

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An axillary mass was detected in a 6-year-old, neutered, male, domestic short-haired cat during a wellness exam. Gross examination following surgical removal revealed a discrete, deep subcutaneous, discoid mass that was between 0.5- and 0.

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Composite pleomorphic xanthoastrocytoma-ganglioglioma (PXA-GG) is an extremely rare central nervous system neoplasm with 2 distinct but intermingled components. Whether this tumor represents a "collision tumor" of separate neoplasms or a monoclonal neoplasm with divergent evolution is poorly understood. Clinicopathologic studies and capture-based next generation sequencing were performed on extracted DNA from all available PXA-GG at 2 medical centers.

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Purpose: The immunosuppressive tumor microenvironment present in the majority of diffuse glioma limits therapeutic response to immunotherapy. As the determinants of the glioma-associated immune response are relatively poorly understood, the study of glioma with more robust tumor-associated immune responses may be particularly useful to identify novel immunomodulatory factors that can promote T-cell effector function in glioma.

Experimental Design: We used multiplex immune-profiling, proteomic profiling, and gene expression analysis to define the tumor-associated immune response in two molecular subtypes of glioma and identify factors that may modulate this response.

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Background: Genomic profiling studies of diffuse gliomas have led to new improved classification schemes that better predict patient outcomes compared to conventional histomorphology alone. One example is the recognition that patients with IDH-wildtype diffuse astrocytic gliomas demonstrating lower-grade histologic features but genomic and/or epigenomic profile characteristic of glioblastoma typically have poor outcomes similar to patients with histologically diagnosed glioblastoma. Here we sought to determine the clinical impact of prospective genomic profiling for these IDH-wildtype diffuse astrocytic gliomas lacking high-grade histologic features but with molecular profile of glioblastoma.

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Rosai Dorfman disease is a rare histiocytic disorder of over-production of non-Langerhans histiocytes, which typically manifests with massive lymphadenopathy and sinonasal involvement. We report a rare case of systemic and disseminated craniospinal Rosai Dorfman disease with intraparenchymal and leptomeningeal involvement, but no sinus or dural-based disease. The diagnosis was established by biopsy of a hypothalamic mass.

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'Intracranial mesenchymal tumor, FET-CREB fusion-positive' occurs primarily in children and young adults and has previously been termed intracranial angiomatoid fibrous histiocytoma (AFH) or intracranial myxoid mesenchymal tumor (IMMT). Here we performed genome-wide DNA methylation array profiling of 20 primary intracranial mesenchymal tumors with FET-CREB fusion to further study their ontology. These tumors resolved into two distinct epigenetic subgroups that were both divergent from all other analyzed intracranial neoplasms and soft tissue sarcomas, including meningioma, clear cell sarcoma of soft tissue (CCS), and AFH of extracranial soft tissue.

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Background: "Diffuse midline glioma (DMG), H3 K27M-mutant" is a new tumor entity established in the 2016 WHO classification of Tumors of the Central Nervous System that comprises a set of diffuse gliomas arising in midline structures and is molecularly defined by a K27M mutation in genes encoding the histone 3 variants H3.3 or H3.1.

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Intracranial mesenchymal tumors with FET-CREB fusions are a recently described group of neoplasms in children and young adults characterized by fusion of a FET family gene (usually EWSR1, but rarely FUS) to a CREB family transcription factor (ATF1, CREB1, or CREM), and have been variously termed intracranial angiomatoid fibrous histiocytoma or intracranial myxoid mesenchymal tumor. The clinical outcomes, histologic features, and genomic landscape are not well defined. Here, we studied 20 patients with intracranial mesenchymal tumors proven to harbor FET-CREB fusion by next-generation sequencing (NGS).

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Food authenticity concerning the geographical origin becomes increasingly important for consumers, food industries, and food authorities. In this study, H NMR metabolomics combined with machine learning methodologies was applied to successfully distinguish the geographical origin of 237 samples of white asparagus from Germany, Poland, The Netherlands, Spain, Greece, and Peru. Support vector classification of the geographical origin achieved an accuracy of 91.

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Objectives: Birth season has been inconsistently associated with anthropometrics, bone fractures, and malocclusion. Our aim was to assess the association between birth season and anthropometrics (height, weight, birth weight), bone fractures and dental malocclusion in the United States.

Methods: US surveys conducted between 1963-1973 assessed 16 152 6-to-21-year-old participants.

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Paragangliomas are neuroendocrine tumors of the autonomic nervous system that are variably clinically functional and have a potential for metastasis. Up to 40% occur in the setting of a hereditary syndrome, most commonly due to germline mutations in succinate dehydrogenase (SDHx) genes. Immunohistochemically, paragangliomas are characteristically GATA3-positive and cytokeratin-negative, with loss of SDHB expression in most hereditary cases.

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The FGFR1 gene encoding fibroblast growth factor receptor 1 has emerged as a frequently altered oncogene in the pathogenesis of multiple low-grade neuroepithelial tumor (LGNET) subtypes including pilocytic astrocytoma, dysembryoplastic neuroepithelial tumor (DNT), rosette-forming glioneuronal tumor (RGNT), and extraventricular neurocytoma (EVN). These activating FGFR1 alterations in LGNET can include tandem duplication of the exons encoding the intracellular tyrosine kinase domain, in-frame gene fusions most often with TACC1 as the partner, or hotspot missense mutations within the tyrosine kinase domain (either at p.N546 or p.

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