331 research outputs found
Naphthalene-2,3-diol–imidazole (1/1)
In the title cocrystal, C10H8O2·C3H4N2, intermolecular O—H⋯O and N—H⋯O hydrogen bonds connect the naphthalene-2,3-diol and imidazole molecules into a two-dimensional supramolecular framework
Crystal structure of the yellow 1:2 molecular complex lumiflavin–bisnaphthalene-2,3-diol
In the first molecular complex of the physiologically active neutral form of isoalloxazine studied, lumiflavin–bisnaphthalene-2,3-diol, each flavin is sandwiched between two naphthalenediol molecules with extensive overlap but a moderately large (3·44 Å) spacing, indicating at most weak charge-transfer interaction and in agreement with the yellow colour of the complex, nearly the same as that of the parent lumiflavin
A study of Erlang ETS table implementations and performance
The viability of implementing an in-memory database, Erlang ETS, using a relatively-new data structure, called a Judy array, was studied by comparing the performance of ETS tables based on four data structures: AVL balanced binary trees, B-trees, resizable linear hash tables, and Judy arrays. The benchmarks used workloads of sequentially- and randomly-ordered keys at table populations from 700 keys to 54 million keys
N-(1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)acetamide–naphthalene-2,3-diol (1/1)
In the reaction of naphthalene-2,3-diol and 4-aminoantipyrine in the presence of acetic acid, the amine function is acetylated and the resulting acetamide co-crystallizes with the diol in the title compound, C13H15N3O2·C10H8O2, with 1:1 molar stoichiometry. The two components are linked by two O–H⋯O=C hydrogen bonds. One of the hydroxy groups interacts with the pyrazolone carbonyl O atom and the other hydroxy group interacts with the amide O atom of another component, generating a chain motif. Adjacent chains are linked into a layer motif via N—H⋯O interactions involving only the heterocyclic acetamide component
Diagnostic Utility of IDH1/2 Mutations to Distinguish Dedifferentiated Chondrosarcoma from Undifferentiated Pleomorphic Sarcoma of Bone
Histologically it is nearly impossible to distinguish the dedifferentiated component of dedifferentiated chondrosarcoma from undifferentiated pleomorphic sarcoma of bone when the low-grade cartilaginous component is absent. Previous studies have revealed that isocitrate dehydrogenase 1 (IDH1) and IDH2 mutations are present in a significant number of cartilaginous tumors including the majority of conventional chondrosarcoma and dedifferentiated chondrosarcomas. These mutations have not been studied in undifferentiated pleomorphic sarcomas of bone. We sought to investigate whether an IDH1 or IDH2 mutation signature could be used as a clinically diagnostic marker for the distinction of dedifferentiated component of chondrosarcoma from undifferentiated pleomorphic sarcoma of bone. Sixty-eight bone tumor cases, including 31 conventional chondrosarcomas, 23 dedifferentiated chondrosarcomas, and 14 undifferentiated pleomorphic sarcomas of bone, were collected for IDH1/2 mutation analysis either using the Qiagen IDH1/2 RGQ PCR Kit or using whole exome sequencing. IDH1/2 mutations were detected in 87% (20/23) of dedifferentiated chondrosarcomas and 30% (6/20) of conventional chondrosarcomas. No mutations were detected in the IDH1/2 codon 132 or codon 172 among 14 UPS of bone. Identification of IDH1 or IDH2 mutations supports the diagnosis of dedifferentiated chondrosarcoma rather than undifferentiated pleomorphic sarcoma of bone while also providing some insight into the pathogenesis of these two lesions
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The impact of histopathology and NAB2-STAT6 fusion subtype in classification and grading of meningeal solitary fibrous tumor/hemangiopericytoma.
Meningeal solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) is a rare tumor with propensity for recurrence and metastasis. Although multiple classification schemes have been proposed, optimal risk stratification remains unclear, and the prognostic impact of fusion status is uncertain. We compared the 2016 WHO CNS tumor grading scheme (CNS-G), a three-tier system based on histopathologic phenotype and mitotic count, to the 2013 WHO soft-tissue counterpart (ST-G), a two-tier system based on mitotic count alone, in a cohort of 133 patients [59 female, 74 male; mean age 54 years (range 20-87)] with meningeal SFT/HPC. Tumors were pathologically confirmed through review of the first tumor resection (n = 97), local recurrence (n = 35), or distant metastasis (n = 1). A STAT6 immunostain showed nuclear expression in 132 cases. NAB2-STAT6 fusion was detected in 99 of 111 successfully tested tumors (89%) including the single STAT6 immunonegative tumor. Tumors were classified by CNS-G as grade 1 (n = 43), 2 (n = 41), or 3 (n = 49), and by ST-G as SFT (n = 84) or malignant SFT (n = 49). Necrosis was present in 16 cases (12%). On follow-up, 42 patients had at least one subsequent recurrence or metastasis (7 metastasis only, 33 recurrence only, 2 patients had both). Twenty-nine patients died. On univariate analysis, necrosis (p = 0.002), CNS-G (p = 0.01), and ST-G (p = 0.004) were associated with recurrence-free (RFS) but not overall survival (OS). NAB2-STAT6 fusion type was not significantly associated with RFS or OS, but was associated with phenotype. A modified ST-G incorporating necrosis showed higher correlation with RFS (p = 0.0006) and remained significant (p = 0.02) when considering only the primary tumors. From our data, mitotic rate and necrosis appear to stratify this family of tumors most accurately and could be incorporated in a future grading scheme
Inflammatory Leiomyosarcoma and Histiocyte-rich Rhabdomyoblastic Tumor : a clinicopathological, immunohistochemical and genetic study of 13 cases, with a proposal for reclassification as Inflammatory Rhabdomyoblastic Tumor
Inflammatory leiomyosarcoma (ILMS), defined as a malignant neoplasm showing smooth muscle differentiation, a prominent inflammatory infiltrate, and near-haploidization , is a very rare soft tissue tumor with a generally favorable prognosis. The morphologic features of histiocyte-rich rhabdomyoblastic tumor (HRRMT) are similar to those of ILMS, although this lesion shows by definition a skeletal muscle phenotype. Recent gene expression profiling and immunohistochemical studies have also suggested that ILMS and HRRMT may be related. We studied the clinicopathologic, immunohistochemical and genetic features of four cases previously classified as ILMS and nine classified as HRRMT. Tumors from both groups tended to occur in the deep soft tissues of the extremities of young to middle-aged males and exhibited indolent behavior. Morphologically, all were well-circumscribed, often encapsulated, and showed a striking histiocyte-rich inflammatory infiltrate admixed with variably pleomorphic tumor cells showing spindled and epithelioid to rhabdoid morphology, eosinophilic cytoplasm, and prominent nucleoli, but few, if any, mitotic figures. Immunohistochemically, the tumor cells expressed desmin, alpha-smooth muscle actin, and the rhabdomyoblastic markers PAX7, MyoD1, and myogenin. H-caldesmon expression was absent in all cases, using the specific h-CD antibody. Karyotypic study (1 HRRMT) and genome-wide copy number analysis (7 HRRMT, OncoScan SNP assay), revealed near-haploidization in four cases, with subsequent genome doubling in one, an identical phenotype to that seen in ILMS. We propose reclassification of ILMS and HRRMT as inflammatory rhabdomyoblastic tumor , a name which accurately describes the salient morphologic and immunohistochemical features of this distinctive tumor, as well as its intermediate (rarely metastasizing) clinical behavior
Inter- and Intraobserver Reliability and Validation of a New Method for Determination of Eosinophil Counts in Patients with Esophageal Eosinophilia
Diagnosis of eosinophilic esophagitis (EoE) requires quantification of esophageal eosinophilia
Tryptase Staining of Mast Cells May Differentiate Eosinophilic Esophagitis from Gastroesophageal Reflux Disease
Mast cells may contribute to the pathogenesis of eosinophilic esophagitis (EoE), but their role in diagnosis is unknown. Our aim was to determine whether tryptase staining of esophageal mast cells differentiates EoE from GERD and has utility for diagnosis of EoE
Clinical, Endoscopic, and Histologic Findings Distinguish Eosinophilic Esophagitis From Gastroesophageal Reflux Disease
Features of eosinophilic esophagitis (EoE) and gastroesophageal reflux disease (GERD) overlap; because they cannot be differentiated based on eosinophil counts alone, it can be a challenge to distinguish between these disorders. We aimed to characterize the clinical, endoscopic, and histologic features of EoE and GERD and identify factors that might be used to differentiate them
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