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1.
Sci Rep ; 14(1): 15504, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969719

RESUMEN

Time-resolved X-ray magnetic circular dichroism under the effects of ferromagnetic resonance (FMR), known as X-ray ferromagnetic resonance (XFMR) measurements, enables direct detection of precession dynamics of magnetic moment. Here we demonstrated XFMR measurements and Bayesian analyses as a quantitative probe for the precession of spin and orbital magnetic moments under the FMR effect. Magnetization precessions in two different Pt/Ni-Fe thin film samples were directly detected. Furthermore, the ratio of dynamical spin and orbital magnetic moments was evaluated quantitatively by Bayesian analyses for XFMR energy spectra around the Ni L 2 , 3 absorption edges. Our study paves the way for a microscopic investigation of the contribution of the orbital magnetic moment to magnetization dynamics.

2.
Phys Chem Chem Phys ; 26(18): 13634-13638, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38685819

RESUMEN

The cononsolvency mechanism of poly(N-isopropylacrylamide) (PNIPAM), dissolving in pure methanol (MeOH) and water (H2O) but being insoluble in MeOH-H2O mixtures, was investigated by O K-edge X-ray absorption spectroscopy (XAS). The cononsolvency emerges from the aggregation of PNIPAM with MeOH clusters, leading to the collapse of the hydrophobic hydration of PNIPAM.

3.
J Neurooncol ; 166(2): 273-282, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38227143

RESUMEN

PURPOSE: Liquid biopsy of cyst fluid in brain tumors has not been extensively studied to date. The present study was performed to see whether diagnostic genetic alterations found in brain tumor tissue DNA could also be detected in cell-free DNA (cfDNA) of cyst fluid in cystic brain tumors. METHODS: Cyst fluid was obtained from 22 patients undergoing surgery for a cystic brain tumor with confirmed genetic alterations in tumor DNA. Pathological diagnoses based on WHO 2021 classification and diagnostic alterations in the tumor DNA, such as IDH1 R132H and TERT promoter mutation for oligodendrogliomas, were detected by Sanger sequencing. The same alterations were analyzed by both droplet digital PCR (ddPCR) and Sanger sequencing in cyst fluid cfDNA. Additionally, multiplex ligation-dependent probe amplification (MLPA) assays were performed to assess 1p/19q status, presence of CDKN2A loss, PTEN loss and EGFR amplification, to assess whether differentiating between astrocytomas and oligodendrogliomas and grading is possible from cyst fluid cfDNA. RESULTS: Twenty-five genetic alterations were found in 22 tumor samples. All (100%) alterations were detected in cyst fluid cfDNA by ddPCR. Twenty of the 25 (80%) alterations were also detected by Sanger sequencing of cyst fluid cfDNA. Variant allele frequency (VAF) in cyst fluid cfDNA was comparable to that of tumor DNA (R = 0.62, Pearson's correlation). MLPA was feasible in 11 out of 17 (65%) diffuse gliomas, with close correlation of results between tumor DNA and cyst fluid cfDNA. CONCLUSION: Cell-free DNA obtained from cyst fluid in cystic brain tumors is a reliable alternative to tumor DNA when diagnosing brain tumors.


Asunto(s)
Neoplasias Encefálicas , Ácidos Nucleicos Libres de Células , Oligodendroglioma , Humanos , Oligodendroglioma/diagnóstico , Oligodendroglioma/genética , Oligodendroglioma/patología , Líquido Quístico , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Mutación , Reacción en Cadena de la Polimerasa Multiplex , ADN
4.
J Phys Chem A ; 128(3): 611-617, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38227306

RESUMEN

Carbon (C) K-edge X-ray absorption spectra for firefly luciferin were measured and assigned using time-dependent density functional theoretical calculations for luciferin anion and dianion to elucidate the effect of hydroxy-group deprotonation. It was found that the C K-edge spectra for luciferin had four characteristic peaks. The effect of deprotonation of the hydroxy group appears in the energy difference of the first and second peaks of these spectra. This energy difference is 1.0 eV at pH 7 and 2.3 eV at pH 10. The deprotonation of the hydroxy group can be distinguished based on the soft X-ray absorption spectra.

5.
Neuropathology ; 44(2): 126-134, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37641451

RESUMEN

Neuropil-like islands (NIs) are a histologic hallmark of glioneuronal tumors with neuropil-like islands (GTNIs), but GTNIs are presently not considered a homogeneous entity. The essence of GTNI is likely its glial component, and NIs are now considered aberrant neuronal differentiation or metaplasia. The case we report herein is a 41-year-old woman who was synchronously affected by two brain tumors: one was a glioblastoma (glioblastoma multiforme, GBM), of isocitrate dehydrogenase (IDH)-wild type, with NIs in the left parietal lobe, and the other was histologically a composite gangliocytoma (GC)/anaplastic ganglioglioma (GG) with NIs in the right medial temporal lobe. While both tumors were genetically wild type for IDH, histone H3, and v-raf murine sarcoma viral oncogene homolog B1 (BRAF), the former tumor, but not the latter, was mutated for telomerase reverse transcriptase promoter gene (TERT). A recent systematic study using DNA methylation profiling and next-generation sequencing showed that anaplastic GG separate into other WHO tumor types, including IDH-wild-type GBM. It suggested a diagnostic scheme where an anaplastic GG is likely an IDH-wild-type GBM if it is a BRAF wild type, IDH wild type, and TERT promoter mutant tumor. The likely scenario in this patient is that the GBM results from the progression of GC/anaplastic GG due to the superimposed TERT promoter mutation and the propagation of newly generated GBM cells in the contralateral hemisphere. A systematic analysis using DNA methylation profiling and next-generation sequencing was not available in this study, but the common presence of NIs histologically noted in the two tumors could support this scenario. Although a sufficient volume of molecular and genetic testing is sine qua non for the accurate understanding of brain tumors, the importance of histologic observation cannot be overemphasized.


Asunto(s)
Neoplasias Encefálicas , Ganglioglioma , Ganglioneuroma , Glioblastoma , Telomerasa , Femenino , Ratones , Animales , Humanos , Adulto , Glioblastoma/complicaciones , Glioblastoma/genética , Glioblastoma/patología , Ganglioglioma/patología , Proteínas Proto-Oncogénicas B-raf/genética , Ganglioneuroma/patología , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neurópilo/patología , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Mutación , Telomerasa/genética
6.
Case Rep Oncol ; 16(1): 1054-1059, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900802

RESUMEN

Most elderly patients with tuberculosis (TB) have previously been infected with Mycobacterium tuberculosis, which remains dormant in the body for decades and may reactivate when their immunity declines due to underlying diseases. Elderly cancer patients are at a high risk for TB, and the treatment of TB reactivation in these patients is challenging. Among cancer patients, the incidence of TB reactivation is the highest in lymphoma patients. However, the impact of chemotherapy on TB reactivation in lymphoma patients is unknown. We report the case of an immunocompetent elderly patient with primary central nervous system lymphoma (PCNSL) having no prior history of TB, who developed miliary TB during multiagent chemotherapy consisting of rituximab, high-dose methotrexate, procarbazine, and vincristine (R-MPV therapy). Retrospectively, the chest computed tomography showed calcification of the pleura, suggesting that the patient had a latent tuberculosis infection (LTBI) and developed miliary TB from the reactivation of TB triggered by the R-MPV therapy. Our case emphasizes that when chemotherapy is administered to patients with PCNSL, interferon-gamma release assay (IGRA) should be performed if there are findings on chest examination suggestive of LTBI, such as pleural calcification, and if IGRA is positive, chemotherapy should be given concurrently with LTBI treatment.

7.
J Chem Phys ; 158(10): 104201, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36922146

RESUMEN

Operando time-resolved soft x-ray absorption spectroscopy (TR-SXAS) is an effective method to reveal the photochemical processes of metal complexes in solutions. In this study, we have developed the TR-SXAS measurement system for observing various photochemical reactions in solutions by the combination of laser pump pulses with soft x-ray probe pulses from the synchrotron radiation. For the evaluation of the developed TR-SXAS system, we have measured nitrogen K-edge x-ray absorption spectroscopy (XAS) spectra of aqueous iron phenanthroline solutions during a photoinduced spin transition process. The decay process of the high spin state to the low spin state in the iron complex has been obtained from the ligand side by N K-edge XAS, and the time constant is close to that obtained from the central metal side by time-resolved Fe K-edge XAS in the previous studies.

8.
Childs Nerv Syst ; 39(4): 901-907, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36745216

RESUMEN

PURPOSE: Measuring serum and cerebrospinal fluid human chorionic gonadotropin (hCG) is essential for the diagnosis of intracranial germ cell tumors. There are three types of hCG-related markers in clinical use: hCGß, intact hCG, and total hCG. The best marker for the diagnosis of intracranial germ cell tumors, especially germinoma, is currently unknown. This study aimed to evaluate the usefulness of these hCG-related markers. METHODS: We investigated 19 serum samples obtained from 6 patients with histologically diagnosed germinoma treated in our institute. Serum hCGß, intact hCG, and total hCG values were measured before, during, and after treatment. Samples with hCG values above the lower limits were considered positive. RESULTS: The positivity rates of serum hCGß, intact hCG, and total hCG were 6% (1/17), 47% (7/15), and 42% (8/19), respectively, with the latter two having significantly higher positivity rates than hCGß (p = 0.041). Both intact and total hCGs showed similar values. The median values of hCGß, intact hCG, and total hCG before treatment were 0.1 ng/mL, 4.6 mIU/mL, and 4.5 mIU/mL, respectively. CONCLUSION: Serum intact and total hCGs have higher detection rates than hCGß in patients with germinoma using available commercial measurement tools.


Asunto(s)
Neoplasias Encefálicas , Germinoma , Humanos , Biomarcadores de Tumor , Relevancia Clínica , Gonadotropina Coriónica/líquido cefalorraquídeo , Gonadotropina Coriónica Humana de Subunidad beta/líquido cefalorraquídeo , Germinoma/diagnóstico , Neoplasias Encefálicas/diagnóstico
9.
NMC Case Rep J ; 10: 343-348, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38249434

RESUMEN

A central nervous system (CNS) tumor with BCL-6 co-repressor (BCOR) internal tandem duplication (CNS tumor with BCOR ITD) is a rare tumor classified as an embryonal tumor by the World Health Organization classification (5th edition), and the prognosis is generally poor. A successfully treated case is reported, and its treatment is discussed. A five-year-old boy presented with a one-month history of headache and vomiting. Magnetic resonance imaging showed a well-demarcated, left-frontal tumor without perifocal edema. The patient underwent complete resection without a neurological deficit. Anti-BCOR antibody showed strong immunoreactivity in tumor nuclei, and the tumor was diagnosed as a CNS tumor with BCOR ITD. The patient received craniospinal irradiation (CSI) comprising 23.4 Gy, followed by a boost to the primary site to a total dose of 30.6 Gy in daily fractions of 1.8 Gy. The chemotherapy comprised four cycles of vincristine, cyclophosphamide, and cisplatin with peripheral blood stem cell rescue. The clinical course was uneventful throughout the treatment, the tumor has not recurred for four years, and no neurological impairment was reported. CSI and multiagent chemotherapy were effective for a CNS tumor with BCOR ITD.

10.
Br J Neurosurg ; : 1-7, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36469605

RESUMEN

Most pituitary adenoma/neuroendocrine tumours (PitNET) are histologically benign and grow slowly; however, a subset of these tumours exhibit a more aggressive clinical course characterized by local invasiveness and early recurrence. These high-risk PitNETs often require multiple surgeries and radiation over several years and may eventually acquire carcinomatous characteristics, such as metastasis in some cases. Herein, we report a rare case of PitNET causing oculomotor paresis with extremely rapid recurrence only 3 months after initial surgery, followed by lethal liver metastasis. Preoperative magnetic resonance imaging and intraoperative findings were consistent with typical PitNETs, other than moderate invasion of the cavernous sinus. Pathological examination of the specimen obtained from the initial transsphenoidal surgery revealed increased mitosis and elevated rates of cells positive for Ki-67 and p53. Based on the immunohistochemical assessment for transcription factors and pituitary hormones, the diagnosis was determined to be a silent sparsely granulated corticotroph PitNET with focal malignant transformation. Aggressive features represented by Ki-67 and p53 positivity were more robust in recurrent and metastatic specimens, but hormone immunostaining was decreased. Epigenetic analysis revealed methylation of the telomerase reverse transcriptase (TERT) promoter in the tumour, resulting in TERT upregulation. Despite extensive research, markers for distinguishing extremely aggressive PitNETs have not been determined. Although further analysis is needed, our case demonstrates the possible usefulness of assessing TERT promoter methylation status in the stratification of recurrence risk in extremely high-risk variants of PitNET.

11.
J Synchrotron Radiat ; 29(Pt 6): 1414-1419, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36345749

RESUMEN

A picosecond pump-probe resonant soft X-ray scattering measurement system has been developed at the Photon Factory storage ring for highly efficient data collection. A high-repetition-rate high-power compact laser system has been installed to improve efficiency via flexible data acquisition to a sub-MHz frequency in time-resolved experiments. Data are acquired by gating the signal of a channel electron multiplier with a pulse-counting mode capable of discriminating single-bunch soft X-ray pulses in the dark gap of the hybrid operation mode in the storage ring. The photoinduced dynamics of magnetic order for multiferroic manganite SmMn2O5 are clearly demonstrated by the detection of transient changes in the resonant soft X-ray scattering intensity around the Mn LIII- and O K-edges.

12.
J Neurosurg Case Lessons ; 3(12)2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36273864

RESUMEN

BACKGROUND: Primary intramedullary spinal cord (IMSC) pilocytic astrocytoma (PA) with anaplasia is extremely rare. OBSERVATIONS: A 50-year-old man presented to our hospital with numbness of the left posterior rib region, back, and bilateral lower limbs. Contrast-enhanced T1-weighted magnetic resonance imaging (MRI) revealed an intramedullary lesion at T2-T3 with no contrast enhancement. The patient opted for conservative treatment. Eighteen months after the first consultation, the patient presented with slowly progressive numbness of the bilateral upper limbs, paraparesis, and dysuria, with rapid deterioration over the following 3 months. T1- and T2-weighted MRI revealed expansion of the intramedullary lesion, which extended from C7 to T5, and syringomyelia at C5-C6. Contrast-enhanced T1-weighted MRI revealed an enhancing intramedullary lesion at C7-T5. Open biopsy and C5-T5 laminectomy were performed for diagnosis and decompression. PA with anaplasia was diagnosed based on pathological and immunohistochemical findings. The patient received postoperative radiotherapy and chemotherapy. LESSONS: Rapidly progressive IMSC PA with a change in contrast enhancement is extremely rare in adults. PA may undergo a spontaneous malignant transformation during its natural clinical course. In this case, the change in contrast enhancement may have been associated with the malignant transformation of the PA.

13.
J Neurosurg Case Lessons ; 4(3): CASE22146, 2022 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-36046704

RESUMEN

BACKGROUND: The revised fourth edition of the World Health Organization classification of central nervous system tumors was published in 2016. Based on this classification, one of the infiltrating glioma entities named "oligoastrocytoma/anaplastic oligoastrocytoma" is discouraged. It is proposed that these mixed gliomas should be classified as diffuse astrocytoma/anaplastic astrocytoma or oligodendroglioma/anaplastic oligodendroglioma when analyzing their genetic alteration. OBSERVATIONS: A 78-year-old female underwent brain computed tomography (CT) because of a traffic accident. Cranial CT revealed a brain tumor in the left temporoparietal lobe; therefore, she was hospitalized. She underwent awake craniotomy. After the operation, she was treated with only local radiotherapy; the authors could not prescribe temozolomide, because she had had levetiracetam-induced pancytopenia. The remaining tumor neuroradiologically disappeared, and she was alive 40 months after the operation without tumor recurrence. LESSONS: Histopathologically, this tumor was diagnosed as an anaplastic oligoastrocytoma with a distinct dual phenotype of astrocytoma and oligodendroglioma components. Genetically, these two components revealed astrocytoma and oligodendroglioma genotypes, respectively. Therefore, the authors considered the integrated diagnosis of the temporal tumor as a true anaplastic oligoastrocytoma with a dual genotype. Interestingly, this case also included an area composed of spindle to oval neoplastic cells that revealed intermediate genetic alterations between astrocytomas and oligodendrogliomas.

14.
Brain Tumor Pathol ; 39(3): 130-138, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35000018

RESUMEN

Pineal parenchymal tumors (PPTs) are clinically rare and a biopsy is often required for a definitive diagnosis. To improve the accuracy of histological assessment of PPTs, we examined the proliferative capacity of PPT cells and investigated DICER1 expression and KBTBD4 mutations. This study included 19 cases of PPTs [3 pineocytomas (PCs), 10 PPTs of intermediate differentiation (PPTID), and 6 pineoblastomas (PBs)]. Immunohistochemistry for Ki-67, PHH3, and DICER1, as well as Sanger sequencing analysis for KBTBD4 mutations, was performed using formalin-fixed paraffin-embedded tissue specimens that were resected during surgery. Tumor cell proliferation was quantified using an image analysis software. For the PHH3 and MIB-1 indices, a significant difference was observed between the PPTIDs and PBs (P < 0.05). Loss of DICER1 was not specific for PB; 0/3 PCs (0.0%), 2/9 PPTIDs (22.2%), and 2/4 PBs (50.0%). KBTBD4 mutations were detected in 1/3 PCs (33.3%), 6/9 PPTIDs (66.7%), and 0/4 PBs (0.0%). Thus, combined application of the proliferative marker index and KBTBD4 mutation analysis may be useful for the differential diagnosis of PPTs. Furthermore, detection of KBTBD4 mutations using Sanger sequencing analysis may support the diagnosis of PPTID.


Asunto(s)
Neoplasias Encefálicas , Proteínas Portadoras , ARN Helicasas DEAD-box , Mutación , Glándula Pineal , Ribonucleasa III , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Proteínas Portadoras/genética , Proliferación Celular/fisiología , ARN Helicasas DEAD-box/biosíntesis , ARN Helicasas DEAD-box/genética , Humanos , Inmunohistoquímica , Glándula Pineal/patología , Ribonucleasa III/biosíntesis , Ribonucleasa III/genética
15.
Cytopathology ; 33(1): 132-137, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34608699

RESUMEN

This report describes the cytological features of granular cell astrocytoma (GCA), to aid in the diagnosis of intraoperative frozen samples of brain lesions, and discuss cytological similarities and differences between GCA, two significant non-neoplastic central nervous system lesions (brain infarction and demyelinating disorder), and three central nervous system tumours (gemistocytic astrocytoma, pleomorphic xanthoastrocytoma, and subependymal giant cell astrocytoma).


Asunto(s)
Astrocitoma , Neoplasias Encefálicas , Astrocitoma/diagnóstico , Astrocitoma/patología , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patología , Humanos
16.
Brain Tumor Pathol ; 38(3): 201-209, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34128111

RESUMEN

Two hot spot mutations (C228T, C250T) in the telomerase reverse transcriptase (TERT) gene are frequently identified in glioblastoma and oligodendroglioma. TERT mutations predicts an aggressive clinical course in isocitrate dehydrogenase (IDH) wild-type astrocytic tumors. Therefore, it is important to accurately detect TERT promoter mutations in glioma. Sanger DNA sequencing is the currently standard method for analyzing TERT mutations. However, PCR amplification in the first step of the sequencing has proven technically difficult because of the high GC content around the TERT mutation. In this report, we described a novel droplet digital PCR (ddPCR) assay to evaluate TERT hot spot mutations in fresh frozen and formalin-fixed paraffin-embedded (FFPE) specimens of glioma and verified the difference in results from the Sanger DNA sequencing results. We obtained the mutant allele fraction for TERT mutations of in a single ddPCR run in all cases, including the micro-dissected FFPE sections. On the contrary, up to twice the DNA sequences were required from fresh frozen tissue to obtain the results, consistent with ddPCR assay. When FFPE specimens were used, more time was required to evaluate TERT mutations through DNA sequencing. DdPCR is an effective and sensitive assay compared to the conventional standard Sanger DNA sequencing.


Asunto(s)
Neoplasias Encefálicas/genética , Análisis Mutacional de ADN/métodos , Glioma/genética , Mutación , Reacción en Cadena de la Polimerasa/métodos , Regiones Promotoras Genéticas/genética , Telomerasa/genética , Humanos , Sensibilidad y Especificidad
17.
Clin Case Rep ; 9(1): 380-385, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33505691

RESUMEN

Pediatric supratentorial ependymomas often have a clear cell morphology and reveal a RELA fusion. When a clear cell neoplasm is intraoperatively diagnosed, intracytoplasmic dot-like inclusions by cytology are a useful cytopathological feature of ependymoma.

18.
Surg Neurol Int ; 12: 612, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34992928

RESUMEN

BACKGROUND: Diffuse midline glioma (DMG) is an invasive astrocytic tumor arisen from midline structures, such as the pons and thalamus. Five cases of DMG in the pineal region have been reported, but the clinical course was poor; there was no case of survival for more than 2 years. CASE DESCRIPTION: We report the case of a 12-year-old boy with DMG in the pineal region who is living a normal daily life for more than 6 years following multimodal treatment. He complained of a headache accompanied by vomiting that had gradually worsened 1 month previously, and initial magnetic resonance imaging revealed a pineal tumor. Germinoma was initially suspected; however, a combination of chemotherapy using carboplatin and etoposide was ineffective. The first surgery was performed through the left occipital transtentorial approach (OTA); the diagnosis was DMG. After 60 Gy radiotherapy concomitant with temozolomide (TMZ), the tumor enlarged. Second surgery was performed through bilateral OTAs, and 90% of the tumor was removed. In addition, stereotactic radiotherapy (30 Gy, six fractions) was administered, and the local equivalent dose in 2 Gy/fraction reached 97.5 Gy. Maintenance chemotherapy using TMZ and bevacizumab was continued for 2 years. After finishing chemotherapy, the enhancing lesion enlarged again, and bevacizumab monotherapy was effective. Now, at 6 years after diagnosis, the patient leads an ordinary life as a student. CONCLUSION: Maximum resection and high-dose radiotherapy followed by bevacizumab may have been effective in the present case.

19.
Brain Nerve ; 72(10): 1105-1111, 2020 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-33051400

RESUMEN

Meningioma and glioma represent two common primary intracranial tumors. However, the coexistence of these two lesions in the same patient at the same location is rare. Here, we present a case of a fibroblastic meningioma with a secondary glioblastoma occurring at the same location. A 67-year-old woman underwent surgery for a left frontal parasagittal meningioma, and the tumor was subtotally removed. Two years and 11 months after the surgery, the patient had a tumor at the same location with invasion into the adjacent brain, suggesting recurrent meningioma with malignant transformation. The resected tumor was confirmed histopathologically as a glioblastoma. Genetic analysis revealed that the isocitrate dehydrogenase 1 and 2 genes were wild type, and the TERT promoter mutation was detected. The gene analysis suggests that the tumor was a de novo glioblastoma, not a secondary glioblastoma from a lower-grade glioma. (Received April 9, 2020; Accepted May 27, 2020; Published October 1, 2020).


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Meníngeas , Meningioma , Anciano , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Femenino , Glioblastoma/diagnóstico por imagen , Glioblastoma/cirugía , Humanos , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/cirugía , Meningioma/diagnóstico por imagen , Meningioma/cirugía , Recurrencia Local de Neoplasia/cirugía
20.
J Chem Phys ; 152(12): 124301, 2020 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-32241139

RESUMEN

Multi-electron coincidence measurements have been performed at the photon energies for the core-to-valence (1s → π*) and core-to-Rydberg (1s → 3sσ and 3pπ) resonant excitations in N2 in order to investigate the dynamics of multiple Auger-electron emissions from these core-excited states in detail. Peaks due to slow electrons from superexcited atomic fragments are observed in the decay processes by emission of two or three Auger electrons, indicating stepwise (cascade) multiple Auger decays that involve faster dissociations than electronic relaxations. Energy partitions between the emitted electrons enable us to reveal the detailed decay mechanisms for these processes. Branching ratios among the decays by emission of one, two, or three Auger electrons and those between the simultaneous (direct) and stepwise (cascade) processes have been determined for each of the core-excited states. Branching ratios of decay channels resulting in molecular or fragment ions have also been substantiated.

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