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1.
Pathol Res Pract ; 252: 154922, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37984047

RESUMO

INTRODUCTION: Polymorphous low-grade neuroepithelial tumor of the young (PLNTY) is a recently described entity. The clinicopathological features and prognosis of the molecular subgroups of these rare tumors is poorly understood. In this study, we presented a small case series of three new cases and integrated the data with published cases in the literature to characterize the similarities and differences of molecular subgroups of PLNTY. METHODS: We searched our institutional archive for PLNTY cases and searched PubMed and Web of Science for relevant data. Demographic, clinical, radiologic, histopathological, molecular, and follow-up data of our four cases with published cases were integrated for final analyses. RESULTS: We identified three institutional cases of PLNTY. The median age of our patients was 17 years (range: 13-42). All patients had a prior history of chronic seizures and all had tumors affecting the temporal lobes. Histopathologically, all cases showed oligodendroglial-like morphology with intratumoral calcifications and at least partially infiltrative growth patterns. Tumor cells were immunoreactive with CD34 and GFAP. Genetically, all cases harbored BRAF V600E mutations. Integrated analyses, including a total of 67 cases, demonstrated that PLNTYs with FGFR2 mutation were significantly younger (median age 11.0 years) than those with BRAF V600E or FGFR3 fusions (median age 41.0 and 16.0 years, respectively). All BRAF V600E-positive PLNTYs were free of tumor recurrence, while four of PLNTYs in other molecular subgroups developed tumor recurrence by imaging. CONCLUSION: Our study suggests that PLNTYs have distinct clinicopathological features and are driven by genetic alterations in the MAPK pathway. The molecular subgroups of PLNTYs share similar findings, but also demonstrate distinct patient demographics.


Assuntos
Neoplasias Encefálicas , Neoplasias Neuroepiteliomatosas , Humanos , Adolescente , Adulto Jovem , Adulto , Criança , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Recidiva Local de Neoplasia , Proteínas Proto-Oncogênicas B-raf/genética , Relevância Clínica , Neoplasias Neuroepiteliomatosas/genética , Mutação
2.
Tomography ; 8(2): 789-797, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35314642

RESUMO

BACKGROUND AND PURPOSE: Gliomas have been found to alter iron metabolism and transport in ways that result in an expansion of their intracellular iron compartments to support aggressive tumor growth. This study used deep neural network trained quantitative susceptibility mapping to assess basal ganglia iron concentrations in glioma patients. MATERIALS AND METHODS: Ninety-two patients with brain lesions were initially enrolled in this study and fifty-nine met the inclusion criteria. Susceptibility-weighted images were collected at 3.0 T and used to construct quantitative susceptibility maps via a deep neural network-based method. The regions of interest were manually drawn within basal ganglia structures and the mean voxel intensities were extracted and averaged across multiple slices. One-way ANCOVA tests were conducted to compare the susceptibility values of groups of patients based on tumor grade while controlling for age, sex, and tumor type. RESULTS: The mean basal ganglia susceptibility for patients with grade IV tumors was higher than that for patients with grade II tumors (p = 0.00153) and was also higher for patients with grade III tumors compared to patients with grade II tumors (p = 0.020), after controlling for age, sex, and tumor type. Patient age influenced susceptibility values (p = 0.00356), while sex (p = 0.69) and tumor type (p = 0.11) did not. CONCLUSIONS: The basal ganglia iron content increased with glioma severity. Basal ganglia iron levels may thus be a useful biomarker in glioma prognosis and treatment, especially with regard to iron-based cancer therapies.


Assuntos
Glioma , Ferro , Gânglios da Base/diagnóstico por imagem , Gânglios da Base/metabolismo , Biomarcadores/metabolismo , Glioma/diagnóstico por imagem , Humanos , Ferro/metabolismo , Imageamento por Ressonância Magnética/métodos
3.
Cureus ; 11(12): e6522, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-32025441

RESUMO

Cancer of unknown primary is defined as a metastatic disease present in the absence of an identifiable primary site of origin. Squamous cell carcinoma (SCC) of unknown primary is a relatively uncommon subtype that usually involves metastases to the cervical or inguinal lymph nodes. We present a rare case of SCC of unknown primary metastasizing to the gallbladder fossa and creating a duodenal fistula. This case highlights the rarity of SCCs in the gallbladder region and the risks posed by chemotherapy in patients with gastrointestinal fistulas.

4.
J Org Chem ; 83(17): 10505-10509, 2018 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-30113839

RESUMO

Two N-substituted trinitroalkyl azoles, one triazole, and one tetrazole were synthesized and isolated via efficient cyclization reactions. Both materials were thoroughly characterized, and their structures were confirmed by X-ray diffraction. The formation of the N-trinitroethyl substituted triazole proceeds unexpectedly via nitrosation of an N-substituted diaminomaleonitrile initially with HNO3 and subsequently confirmed with HNO2. The N-trinitropropyl substituted tetrazole was prepared via a standard cyclization route from trinitropropylammonium chloride with orthoformate and azide.

5.
J Phys Chem A ; 122(12): 3287-3292, 2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29513983

RESUMO

Isocyanic acid, HNCO, the imide of carbon dioxide, was prepared by reaction of stearic acid and potassium cyanate (KOCN) at 60 °C in a sealed, thoroughly dried reactor. Interestingly, its crystal structure, solved by X-ray single crystal diffraction at 123(2) K, shows a group-subgroup relation for the NCO- anion to carbon dioxide: (for CO2, cP12, Pa3̅, a = 5.624(2) Å, 150 K, C-O 1.151(2) Å; for HNCO, oP16, Pca21, a = 5.6176(9), b = 5.6236(8), c = 5.6231(7) Å, 123(2) K). Precise positions of H, N, C, and O were determined by DFT calculations with WIEN2k leading to interatomic distances C-O 1.17, C-N 1.22, N-H 1.03, and -N-H···N 2.14 Å, and the interatomic angle N-C-O 171°.

6.
Cureus ; 10(12): e3681, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30761233

RESUMO

Burnout has reached rampant levels among United States (US) healthcare professionals, with over one-half of physicians and one-third of nurses experiencing symptoms. The burnout epidemic is detrimental to patient care and may exacerbate the impending physician shortage. This review gives a brief history of burnout and summarizes its main causes, effects, and prevalence among US healthcare workers. It also lists some strategies that physicians, organizations, and medical schools can employ to counter the epidemic.

7.
Inorg Chem ; 55(9): 4683-92, 2016 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-27070931

RESUMO

Four silanes based on the neo-pentane skeleton Me4-xSi(CH2R)x containing carbamate groups (x = 1-4, R = OC(O)NH2) have been prepared via the corresponding alcohols Me4-xSi(CH2OH)x, starting from the chlorosilanes Me4-xSiClx. Subsequent nitration leads to the corresponding primary nitrocarbamates (R = OC(O)NHNO2), examined for the purpose as potential energetic materials, including the silicon analogue of pentaerythritol tetranitrocarbamate (sila-PETNC) and a siloxane based nitrocarbamate side-product. All compounds were thoroughly characterized by spectroscopic methods including X-ray diffraction. Thermal stabilities and sensitivities toward impact and friction were examined, as well as detonation values by calculating energies of formation using the EXPLO5 V6.02 software.

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