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1.
Acta Neuropathol Commun ; 12(1): 93, 2024 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867333

RESUMO

Choroid plexus tumors (CPTs) are intraventricular tumors derived from the choroid plexus epithelium and occur frequently in children. The aim of this study was to investigate the genomic and epigenomic characteristics of CPT and identify the differences between choroid plexus papilloma (CPP) and choroid plexus carcinoma (CPC). We conducted multiomics analyses of 20 CPT patients including CPP and CPC. Multiomics analysis included whole-genome sequencing, whole-transcriptome sequencing, and methylation sequencing. Mutually exclusive TP53 and EPHA7 point mutations, coupled with the amplification of chromosome 1, were exclusively identified in CPC. In contrast, amplification of chromosome 9 was specific to CPP. Differential gene expression analysis uncovered a significant overexpression of genes related to cell cycle regulation and epithelial-mesenchymal transition pathways in CPC compared to CPP. Overexpression of genes associated with tumor metastasis and progression was observed in the CPC subgroup with leptomeningeal dissemination. Furthermore, methylation profiling unveiled hypomethylation in major repeat regions, including long interspersed nuclear elements, short interspersed nuclear elements, long terminal repeats, and retrotransposons in CPC compared to CPP, implying that the loss of epigenetic silencing of transposable elements may play a role in tumorigenesis of CPC. Finally, the differential expression of AK1, regulated by both genomic and epigenomic factors, emerged as a potential contributing factor to the histological difference of CPP against CPC. Our results suggest pronounced genomic and epigenomic disparities between CPP and CPC, providing insights into the pathogenesis of CPT at the molecular level.


Assuntos
Carcinoma , Neoplasias do Plexo Corióideo , Papiloma do Plexo Corióideo , Humanos , Neoplasias do Plexo Corióideo/genética , Neoplasias do Plexo Corióideo/patologia , Neoplasias do Plexo Corióideo/metabolismo , Feminino , Masculino , Papiloma do Plexo Corióideo/genética , Papiloma do Plexo Corióideo/patologia , Criança , Pré-Escolar , Carcinoma/genética , Carcinoma/patologia , Metilação de DNA , Lactente , Adolescente , Multiômica
2.
Brain ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916065

RESUMO

Somatic mosaicism in a fraction of brain cells causes neurodevelopmental disorders, including childhood intractable epilepsy. However, the threshold for somatic mosaicism leading to brain dysfunction is unknown. In this study, we induced various mosaic burdens in focal cortical dysplasia type II (FCD II) mice, featuring mTOR somatic mosaicism and spontaneous behavioral seizures. The mosaic burdens ranged from approximately 1,000 to 40,000 neurons expressing the mTOR mutant in the somatosensory (SSC) or medial prefrontal (PFC) cortex. Surprisingly, approximately 8,000 to 9,000 neurons expressing the MTOR mutant, which are extrapolated to constitute 0.08-0.09% of total cells or roughly 0.04% of variant allele frequency (VAF) in the mouse hemicortex, were sufficient to trigger epileptic seizures. The mutational burden was correlated with seizure frequency and onset, with a higher tendency for electrographic inter-ictal spikes and beta- and gamma-frequency oscillations in FCD II mice exceeding the threshold. Moreover, mutation-negative FCD II patients in deep sequencing of their bulky brain tissues revealed somatic mosaicism of the mTOR pathway genes as low as 0.07% in resected brain tissues through ultra-deep targeted sequencing (up to 20 million reads). Thus, our study suggests that extremely low levels of somatic mosaicism can contribute to brain dysfunction.

3.
Micromachines (Basel) ; 15(4)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38675307

RESUMO

We investigated the effects of gate bias regarding the degradation of electrical characteristics during gamma irradiation. Moreover, we observed the punch through failure of 1.2 kV rated commercial Silicon Carbide (SiC) Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) due to the influence of gate bias. In addition, the threshold voltage (VT) and on-resistance (Ron) of the SiC MOSFETs decreased significantly by the influence of gate bias during gamma irradiation. We extracted the concentration of carriers and fixed charge (QF) in oxide using N-type SiC MOS capacitors and Transmission Line Measurement (TLM) patterns to analyze the effects of gamma irradiation. The Total Ionizing Dose (TID) effect caused by high-energy gamma-ray irradiation resulted in an increase in the concentration of holes and QF in both SiC and oxide. To analyze the phenomenon for increment of hole concentration in the device under gate bias, we extracted the subthreshold swing of SiC MOSFETs and verified the origin of TID effects accelerated by the gate bias. The QF and doping concentration of p-well values extracted from the experiments were used in TCAD simulations (version 2022.03) of the planar SiC MOSFET. As a result of analyzing the energy band diagram at the channel region of 1.2 kV SiC MOSFETs, it was verified that punch-through can occur in 1.2 kV SiC MOSFETs when the gate bias is applied, as the TID effect is accelerated by the gate bias.

4.
Cancer Res Treat ; 56(2): 652-664, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38037318

RESUMO

PURPOSE: The Korean Society of Pediatric Neuro-Oncology (KSPNO) conducted treatment strategies for children with medulloblastoma (MB) by using alkylating agents for maintenance chemotherapy or tandem high-dose chemotherapy (HDC) with autologous stem cell rescue (ASCR) according to the risk stratification. The purpose of the study was to assess treatment outcomes and complications based on risk-adapted treatment and HDC. MATERIALS AND METHODS: Fifty-nine patients diagnosed with MB were enrolled in this study. Patients in the standard-risk (SR) group received radiotherapy (RT) after surgery and chemotherapy using the KSPNO M051 regimen. Patients in the high-risk (HR) group received two and four chemotherapy cycles according to the KSPNO S081 protocol before and after reduced RT for age following surgery and two cycles of tandem HDC with ASCR consolidation treatment. RESULTS: In the SR group, 24 patients showed 5-year event-free survival (EFS) and overall survival (OS) estimates of 86.7% (95% confidence interval [CI], 73.6 to 100) and 95.8% (95% CI, 88.2 to 100), respectively. In the HR group, more infectious complications and mortality occurred during the second HDC than during the first. In the HR group, the 5-year EFS and OS estimates were 65.5% (95% CI, 51.4 to 83.4) and 72.3% (95% CI, 58.4 to 89.6), respectively. CONCLUSION: High intensity of alkylating agents for SR resulted in similar outcomes but with a high incidence of hematologic toxicity. Tandem HDC with ASCR for HR induced favorable EFS and OS estimates compared to those reported previously. However, infectious complications and treatment-related mortalities suggest that a reduced chemotherapy dose is necessary, especially for the second HDC.


Assuntos
Neoplasias Cerebelares , Transplante de Células-Tronco Hematopoéticas , Meduloblastoma , Criança , Humanos , Meduloblastoma/terapia , Meduloblastoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Cerebelares/diagnóstico , Neoplasias Cerebelares/tratamento farmacológico , Alquilantes/uso terapêutico , Terapia Combinada
5.
Biomolecules ; 13(5)2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37238617

RESUMO

The immunomodulatory imide drug (IMiD) class, which includes the founding drug member thalidomide and later generation drugs, lenalidomide and pomalidomide, has dramatically improved the clinical treatment of specific cancers, such as multiple myeloma, and it combines potent anticancer and anti-inflammatory actions. These actions, in large part, are mediated by IMiD binding to the human protein cereblon that forms a critical component of the E3 ubiquitin ligase complex. This complex ubiquitinates and thereby regulates the levels of multiple endogenous proteins. However, IMiD-cereblon binding modifies cereblon's normal targeted protein degradation towards a new set of neosubstrates that underlies the favorable pharmacological action of classical IMiDs, but also their adverse actions-in particular, their teratogenicity. The ability of classical IMiDs to reduce the synthesis of key proinflammatory cytokines, especially TNF-α levels, makes them potentially valuable to reposition as drugs to mitigate inflammatory-associated conditions and, particularly, neurological disorders driven by an excessive neuroinflammatory element, as occurs in traumatic brain injury, Alzheimer's and Parkinson's diseases, and ischemic stroke. The teratogenic and anticancer actions of classical IMiDs are substantial liabilities for effective drugs in these disorders and can theoretically be dialed out of the drug class. We review a select series of novel IMiDs designed to avoid binding with human cereblon and/or evade degradation of downstream neosubstrates considered to underpin the adverse actions of thalidomide-like drugs. These novel non-classical IMiDs hold potential as new medications for erythema nodosum leprosum (ENL), a painful inflammatory skin condition associated with Hansen's disease for which thalidomide remains widely used, and, in particular, as a new treatment strategy for neurodegenerative disorders in which neuroinflammation is a key component.


Assuntos
Mieloma Múltiplo , Doenças Neurodegenerativas , Humanos , Talidomida/farmacologia , Talidomida/uso terapêutico , Agentes de Imunomodulação , Doenças Neuroinflamatórias , Mieloma Múltiplo/tratamento farmacológico , Ubiquitina-Proteína Ligases/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico
6.
Yonsei Med J ; 64(3): 191-196, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36825345

RESUMO

PURPOSE: This study aimed to analyze the effect of foramen magnum decompression with C1 laminectomy (C1L) for Chiari malformation type 1 (CM-1) in terms of improving clinical symptoms, expanding posterior fossa volume, and decreasing syrinx volume. MATERIALS AND METHODS: Between January 2007 and June 2019, 107 patients with CM-1 were included. The median patient age was 13±13 years (range: 9 months-60 years), female-to-male ratio was 1:1, and average length of tonsil herniation was 13±5 mm (range: 5-24 mm). Surgical techniques were divided into four groups based on duraplasty or C1L usage. Among the study subjects, 38 patients underwent duraplasty and had their syrinx volumes measured separately on serial magnetic resonance imaging. A three-dimensional visualization software was used to evaluate the syrinx-volume decrease rate. RESULTS: Bony decompression exhibited a mere 20% volume expansion of the lower-half posterior fossa. C1L offered a 3% additional volume expansion, which rose to 5% when duraplasty was added (p=0.029). There were no significant differences in complication rate when C1L was combined with duraplasty (p=0.526). Syrinx volumes were analyzed in 38 patients who had undergone duraplasty. Among them, 28 patients who had undergone duraplasty without C1L demonstrated a 5.9% monthly decrease in syrinx volume, which was 7.5% in the remaining 10 patients with C1L (p=0.040). CONCLUSION: C1L was effective in increasing posterior fossa volume expansion, both with and without duraplasty. A more rapid decrease in syrinx volume occurred when C1L was combined with duraplasty.


Assuntos
Malformação de Arnold-Chiari , Procedimentos de Cirurgia Plástica , Siringomielia , Humanos , Masculino , Feminino , Lactente , Laminectomia , Descompressão Cirúrgica/métodos , Dura-Máter/patologia , Dura-Máter/cirurgia , Malformação de Arnold-Chiari/diagnóstico por imagem , Malformação de Arnold-Chiari/cirurgia , Siringomielia/diagnóstico por imagem , Siringomielia/cirurgia , Siringomielia/patologia , Imageamento por Ressonância Magnética , Resultado do Tratamento , Estudos Retrospectivos
7.
Ann Neurol ; 93(6): 1082-1093, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36700525

RESUMO

OBJECTIVE: Brain somatic mutations in mTOR pathway genes are a major genetic etiology of focal cortical dysplasia type II (FCDII). Despite a greater ability to detect low-level somatic mutations in the brain by deep sequencing and analytics, about 40% of cases remain genetically unexplained. METHODS: We included 2 independent cohorts consisting of 21 patients with mutation-negative FCDII without apparent mutations on conventional deep sequencing of bulk brain. To find ultra-low level somatic variants or structural variants, we isolated cells exhibiting phosphorylation of the S6 ribosomal protein (p-S6) in frozen brain tissues using fluorescence-activated cell sorting (FACS). We then performed deep whole-genome sequencing (WGS; >90×) in p-S6+ cells in a cohort of 11 patients with mutation-negative. Then, we simplified the method to whole-genome amplification and target gene sequencing of p-S6+ cells in independent cohort of 10 patients with mutation-negative followed by low-read depth WGS (10×). RESULTS: We found that 28.6% (6 of 21) of mutation-negative FCDII carries ultra-low level somatic mutations (less than 0.2% of variant allele frequency [VAF]) in mTOR pathway genes. Our method showed ~34 times increase of the average mutational burden in FACS mediated enrichment of p-S6+ cells (average VAF = 5.84%) than in bulky brain tissues (average VAF = 0.17%). We found that 19% (4 of 21) carried germline structural variations in GATOR1 complex undetectable in whole exome or targeted gene sequencing. CONCLUSIONS: Our method facilitates the detection of ultra-low level somatic mutations, in specifically p-S6+ cells, and germline structural variations and increases the genetic diagnostic rate up to ~80% for the entire FCDII cohort. ANN NEUROL 2023;93:1082-1093.


Assuntos
Epilepsia , Displasia Cortical Focal , Humanos , Serina-Treonina Quinases TOR/genética , Epilepsia/genética , Mutação/genética
8.
PLoS Genet ; 18(9): e1010404, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36121845

RESUMO

Most somatic mutations that arise during normal development are present at low levels in single or multiple tissues depending on the developmental stage and affected organs. However, the effect of human developmental stages or mutations of different organs on the features of somatic mutations is still unclear. Here, we performed a systemic and comprehensive analysis of low-level somatic mutations using deep whole-exome sequencing (average read depth ~500×) of 498 multiple organ tissues with matched controls from 190 individuals. Our results showed that early clone-forming mutations shared between multiple organs were lower in number but showed higher allele frequencies than late clone-forming mutations [0.54 vs. 5.83 variants per individual; 6.17% vs. 1.5% variant allele frequency (VAF)] along with less nonsynonymous mutations and lower functional impacts. Additionally, early and late clone-forming mutations had unique mutational signatures that were distinct from mutations that originated from tumors. Compared with early clone-forming mutations that showed a clock-like signature across all organs or tissues studied, late clone-forming mutations showed organ, tissue, and cell-type specificity in the mutation counts, VAFs, and mutational signatures. In particular, analysis of brain somatic mutations showed a bimodal occurrence and temporal-lobe-specific signature. These findings provide new insights into the features of somatic mosaicism that are dependent on developmental stage and brain regions.


Assuntos
Mosaicismo , Neoplasias , Frequência do Gene , Humanos , Mutação , Neoplasias/genética , Sequenciamento do Exoma
9.
J Neurooncol ; 160(1): 41-53, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36045266

RESUMO

PURPOSE: Non-germinomatous germ cell tumors (NGGCTs) are rare pediatric conditions. This multicenter study using Asian multinational patient data investigated treatment outcomes and prognostic factors for NGGCTs. METHODS: Medical records of 251 patients with NGGCTs treated from 1995 to 2015 were retrospectively analyzed from participating centers in Asian countries (Korea, Taiwan, Singapore, and Japan). RESULTS: The median follow up was 8.5 years (95% CI 7.8-9.9). In the total cohort, 5-year event-free survival (EFS) and overall survival (OS) rates were 78.2% and 85.4%, respectively. In 17.9% of the patients, diagnosis was determined by tumor markers alone (alpha-fetoprotein ≥ 10 ng/mL (Korea) or > 25 ng/mL (Taiwan and Singapore), and/or ß-human chorionic gonadotropin (ß-hCG) ≥ 50 mIU/mL). Patients with immature teratomas and mature teratomas comprised 12.0% and 8.4%, respectively. The 5-year EFS rate was higher in patients with histologically confirmed germinoma with elevated ß-hCG (n = 28) than those in patients with malignant NGGCTs (n = 127). Among malignant NGGCTs, patients with choriocarcinoma showed the highest 5-year OS of 87.6%, while yolk sac tumors showed the lowest OS (68.8%). For malignant NGGCT subgroups, an increase in serum ß-hCG levels by 100 mIU/mL was identified as a significant prognostic factor associated with the EFS and OS. CONCLUSION: Our result shows excellent survival outcomes of overall CNS NGGCT. However, treatment outcome varied widely across the histopathologic subgroup of NGGCT. Hence, this study suggests the necessity for accurate diagnosis by surgical biopsy and further optimization of diagnosis and treatment according to the histopathology of NGGCTs. Future clinical trials should be designed for individualized treatments for different NGGCTs subsets.


Assuntos
Neoplasias Encefálicas , Germinoma , Neoplasias Embrionárias de Células Germinativas , Masculino , Humanos , Criança , Estudos Retrospectivos , Prognóstico , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/terapia , Germinoma/patologia , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/tratamento farmacológico , Gonadotropina Coriônica Humana Subunidade beta
10.
Pharmazie ; 77(6): 186-190, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35751164

RESUMO

The leucine-rich repeat LGI family member 3 (LGI3) has been reported to regulate various functions in epidermal keratinocytes. In this study, we investigated the effects of LGI3 on keratinocyte migration in environments with different glucose concentrations. Our results showed that cell migration is markedly impaired in high-glucose environments compared to in low-glucose environments (control). Nevertheless, the use of LGI3 in high-glucose environments restores cell migration to the normal level. Therefore, we performed LGI3 knockdown to identify the role of LGI3 in cell migration. It was observed that transfecting LGI3 siRNA into HaCaT cells reduces the expression of LGI3 and inhibits wound closure. These results indicate that LGI3 is deeply involved in wound healing in high-glucose environments. Western blot analysis showed that in high-glucose environments, LGI3 increases the phosphorylation of Akt, forkhead box protein O1, and focal adhesion kinase. However, no change was observed in the levels of glycogen synthase kinase 3ß, c-Jun N-terminal kinase, extracellular signal-regulated kinase, or p38 mitogen-activated protein kinase. Further results showed that LY294002, a specific inhibitor of phosphatidylinositol 3-kinase, reduced LGI3-induced cell migration. It is generally known that Akt activation leads to the accumulation of ß-catenin, an important mediator of keratinocyte migration. LGI3 greatly increased the expression of ß-catenin in high-glucose environments comparison to that in the low-glucose environments. Taken together, these data indicate that LGI3 induces keratinocyte migration in high-glucose environments as a result of ß-catenin accumulation via Akt phosphorylation. Therefore, LGI3 can be considered a new treatment option for diabetic wound healing.


Assuntos
Queratinócitos/metabolismo , Cicatrização , beta Catenina , Movimento Celular , Glucose/metabolismo , Humanos , Proteínas do Tecido Nervoso/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , beta Catenina/metabolismo
11.
Pharmaceutics ; 14(5)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35631536

RESUMO

(1) Background: An important concomitant of stroke is neuroinflammation. Pomalidomide, a clinically available immunomodulatory imide drug (IMiD) used in cancer therapy, lowers TNF-α generation and thus has potent anti-inflammatory actions. Well-tolerated analogs may provide a stroke treatment and allow evaluation of the role of neuroinflammation in the ischemic brain. (2) Methods: Two novel pomalidomide derivatives, 3,6'-dithiopomalidomide (3,6'-DP) and 1,6'-dithiopomalidomide (1,6'-DP), were evaluated alongside pomalidomide in a rat middle cerebral artery occlusion (MCAo) stroke model, and their anti-inflammatory actions were characterized. (3) Results: Post-MCAo administration of all drugs lowered pro-inflammatory TNF-α and IL1-ß levels, and reduced stroke-induced postural asymmetry and infarct size. Whereas 3,6'- and 1,6'-DP, like pomalidomide, potently bound to cereblon in cellular studies, 3,6'-DP did not lower Ikaros, Aiolos or SALL4 levels-critical intermediates mediating the anticancer/teratogenic actions of pomalidomide and IMiDs. 3,6'-DP and 1,6'-DP lacked activity in mammalian chromosome aberration, AMES and hERG channel assays -critical FDA regulatory tests. Finally, 3,6'- and 1,6'-DP mitigated inflammation across rat primary dopaminergic neuron and microglia mixed cultures challenged with α-synuclein and mouse LPS-challenged RAW 264.7 cells. (4) Conclusion: Neuroinflammation mediated via TNF-α plays a key role in stroke outcome, and 3,6'-DP and 1,6'-DP may prove valuable as stroke therapies and thus warrant further preclinical development.

12.
Alzheimers Dement ; 18(11): 2327-2340, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35234334

RESUMO

OBJECTIVE: Evaluating the efficacy of 3,6'-dithioPomalidomide in 5xFAD Alzheimer's disease (AD) mice to test the hypothesis that neuroinflammation is directly involved in the development of synaptic/neuronal loss and cognitive decline. BACKGROUND: Amyloid-ß (Aß) or tau-focused clinical trials have proved unsuccessful in mitigating AD-associated cognitive impairment. Identification of new drug targets is needed. Neuroinflammation is a therapeutic target in neurodegenerative disorders, and TNF-α a pivotal neuroinflammatory driver. NEW HYPOTHESIS: AD-associated chronic neuroinflammation directly drives progressive synaptic/neuronal loss and cognitive decline. Pharmacologically mitigating microglial/astrocyte activation without altering Aß generation will define the role of neuroinflammation in AD progression. MAJOR CHALLENGES: Difficulty of TNF-α-lowering compounds reaching brain, and identification of a therapeutic-time window to preserve the beneficial role of neuroinflammatory processes. LINKAGE TO OTHER MAJOR THEORIES: Microglia/astroglia are heavily implicated in maintenance of synaptic plasticity/function in healthy brain and are disrupted by Aß. Mitigation of chronic gliosis can restore synaptic homeostasis/cognitive function.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Animais , Camundongos , Peptídeos beta-Amiloides , Cognição , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia , Doenças Neuroinflamatórias , Plasticidade Neuronal , Fator de Necrose Tumoral alfa
13.
J Clin Neurol ; 18(1): 71-78, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35021279

RESUMO

BACKGROUND AND PURPOSE: A multifactorial antiepileptic mechanism underlies the ketogenic diet (KD), and one of the proposed mechanisms of action is that the KD inhibits the mammalian target of rapamycin (mTOR) pathway. To test this clinically, this study aimed to determine the efficacy of the KD in patients with pathologically confirmed focal cortical dysplasia (FCD) due to genetically identifiable mTOR pathway dysregulation. METHODS: A cohort of patients with pathologically confirmed FCD after epilepsy surgery and who were screened for the presence of germline and somatic mutations related to the mTOR pathway in peripheral blood and resected brain tissue was constructed prospectively. A retrospective review of the efficacy of the prior KD in these patients was performed. RESULTS: Twenty-five patients with pathologically confirmed FCD and who were screened for the presence of detectable somatic mTOR pathway mutations had received a sufficient KD. Twelve of these patients (48.0%) had germline or somatic detectable mTOR pathway mutations. A response was defined as a ≥50% reduction in seizure frequency. The efficacy of the KD after 3 months of dietary therapy was superior in patients with detectable mTOR pathway mutations than in patients without detectable mTOR pathway mutations, although the difference was not statistically significant (responder rates of 58.3% vs. 38.5%, p=0.434). CONCLUSIONS: A greater proportion of patients with mTOR pathway responded to the KD, but there was no statistically significant difference in efficacy of the KD between patients with and without detectable mTOR pathway mutations. Further study is warranted due to the smallness of the sample and the limited number of mTOR pathway genes tested in this study.

14.
Neuro Oncol ; 24(8): 1389-1399, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34935949

RESUMO

BACKGROUND: This multinational study was conducted to report clinical presentations and treatment strategies in patients with intracranial germinomas across selected Asian centers, including failure patterns, risk factors, and outcomes. METHODS: A retrospective data collection and analysis of these patients, treated between 1995 and 2015 from eight healthcare institutions across four countries was undertaken. RESULTS: From the results, 418 patients were analyzed, with a median follow-up of 8.9 years; 79.9% of the patients were M0, and 87.6% had ß-human chorionic gonadotropin values <50 mIU/mL. The 5/10-year overall survival (OS) and recurrence-free survival (RFS) rates were 97.2%/96.2% and 89.9%/86.9%, respectively. RFS was predicted by the radiotherapy (RT) field, with focal RT having the worst outcome, whereas chemotherapy usage had no impact on survival. Among patients who received chemotherapy, response to chemotherapy did not predict survival outcomes. In M0 patients, primary basal ganglia tumors predicted a worse RFS. In patients with bifocal tumors, an extended field RT was associated with better outcomes. In multivariable analysis, only RT fields were associated with RFS. In relapsed patients, salvage rates were high at 85.7%. Additionally, patients who received salvage RT had a better outcome (91.6% vs. 66.7%). CONCLUSIONS: Survival outcomes of patients with germinoma were excellent. Thus, the focus of treatment for intracranial germinoma should be on survivorship. Further studies are warranted to find the optimal intensity and volume of radiation, including the role of chemotherapy in the survival of patients with intracranial germinomas, considering age, primary tumor location, and extent of disease.


Assuntos
Neoplasias Encefálicas , Germinoma , Glândula Pineal , Neoplasias Encefálicas/patologia , Germinoma/tratamento farmacológico , Germinoma/patologia , Humanos , Glândula Pineal/patologia , Estudos Retrospectivos , Terapia de Salvação
15.
ACS Appl Mater Interfaces ; 13(49): 59440-59449, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34792331

RESUMO

While two-dimensional (2D) hexagonal boron nitride (h-BN) is emerging as an atomically thin and dangling bond-free insulating layer for next-generation electronics and optoelectronics, its practical implementation into miniaturized integrated circuits has been significantly limited due to difficulties in large-scale growth directly on epitaxial semiconductor wafers. Herein, the realization of a wafer-scale h-BN van der Waals heterostructure with a 2 in. AlGaN/GaN high-electron mobility transistor (HEMT) wafer using metal-organic chemical vapor deposition is presented. The combination of state-of-the-art microscopic and spectroscopic analyses and theoretical calculations reveals that the heterointerface between ∼2.5 nm-thick h-BN and AlGaN layers is atomically sharp and exhibits a very weak van der Waals interaction without formation of a ternary or quaternary alloy that can induce undesired degradation of device performance. The fabricated AlGaN/GaN HEMT with h-BN shows very promising performance including a cutoff frequency (fT) and maximum oscillation frequency (fMAX) as high as 28 and 88 GHz, respectively, enabled by an effective passivation of surface defects on the HEMT wafer to deliver accurate information with minimized power loss. These findings pave the way for practical implementation of 2D materials integrated with conventional microelectronic devices and the realization of future all-2D electronics.

16.
Sci Rep ; 11(1): 20118, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34635765

RESUMO

We investigate the magnetic properties in carbonyl iron (CI) particles before and after Ni[Formula: see text] and H[Formula: see text] ion beam irradiation. Upon increasing temperatures, the saturation magnetization ([Formula: see text]) in hysteresis loops exhibits an anomalous increase at a high temperature for the unirradiated and the Ni[Formula: see text]-beam-irradiated samples, unlike in H[Formula: see text]-beam-irradiated sample. Moreover, the magnetization values at low and high temperatures are more intense after Ni[Formula: see text] beam irradiation, whereas after H[Formula: see text] beam irradiation those are remarkably suppressed. Hematite ([Formula: see text]-Fe[Formula: see text]O[Formula: see text]) phase introduced on the surface of our CI particles undergoes the Morin transition that was observed in our magnetization-temperature curves. The Morin transition causing canted antiferromagnetism above the Morin temperature was found in the unirradiated and Ni[Formula: see text]-beam-irradiated samples, but not in H[Formula: see text]-beam-irradiated sample. It is thus revealed that the CI particles undergoing the Morin transition cause the anomalous increase in [Formula: see text]. We may suggest that Ni[Formula: see text] ion beam increases uncompensated surface spins on the CI particles resulting in a more steep Morin transition and the intensified [Formula: see text]. Ion-beam irradiation may thus be a good tool for controlling the magnetic properties of CI particles, tailoring our work for future applications.

17.
J Tradit Chin Med ; 41(3): 355-359, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34114391

RESUMO

OBJECTIVE: To investigate the efficacy of horse oil on lipopolysaccharide (LPS)-induced inflammation in human keratinocytes. METHODS: Western blot analysis was performed to measure the expression of cyclooxygenase-2 (COX-2) and IκBα. ELISA was used to analyze prostaglandin E2 (PGE2) levels. RESULTS: Horse oil decreased LPS-induced COX-2 and PGE2 levels in a dose-dependent manner. Nuclear factor-kappa B (NF-κB) plays a key role in the expression of inflammatory cytokines and mediators. Therefore, we investigated the influence of horse oil on the NF-κB signaling pathways. Horse oil inhibited translocation of NF-κB from the cytosol to the nucleus. Furthermore, LPS-induced degradation of IκBα was recovered by horse oil. The activation of p38 mitogen-activated protein kinase (MAPK) reportedly induces degradation of IκBα In agreement with this, LPS activated p38 MAPK and caused IκBα degradation. Conversely, horse oil inhibited LPS-induced p38 MAPK activation and IκBα degradation. In addition, a specific p38 MAPK inhibitor, SB203580, blocked IκBα degradation. CONCLUSION: Horse oil decreased COX-2 and PGE2 by inhibiting p38 MAPK activation, IκBα degradation, and the translocation of NF-κB.


Assuntos
Lipopolissacarídeos , NF-kappa B , Animais , Cavalos , Humanos , Inflamação/tratamento farmacológico , Inflamação/genética , Queratinócitos , NF-kappa B/genética , Óxido Nítrico , Proteínas Quinases p38 Ativadas por Mitógeno/genética
18.
Ann Neurol ; 90(2): 285-299, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34180075

RESUMO

OBJECTIVE: Low-level somatic mosaicism in the brain has been shown to be a major genetic cause of intractable focal epilepsy. However, how a relatively few mutation-carrying neurons are able to induce epileptogenesis at the local network level remains poorly understood. METHODS: To probe the origin of epileptogenesis, we measured the excitability of neurons with MTOR mutation and nearby nonmutated neurons recorded by whole-cell patch-clamp and array-based electrodes comparing the topographic distribution of mutation. Computational simulation is used to understand neural network-level changes based on electrophysiological properties. To examine the underlying mechanism, we measured inhibitory and excitatory synaptic inputs in mutated neurons and nearby neurons by electrophysiological and histological methods using the mouse model and postoperative human brain tissue for cortical dysplasia. To explain non-cell-autonomous hyperexcitability, an inhibitor of adenosine kinase was injected into mice to enhance adenosine signaling and to mitigate hyperactivity of nearby nonmutated neurons. RESULTS: We generated mice with a low-level somatic mutation in MTOR presenting spontaneous seizures. The seizure-triggering hyperexcitability originated from nonmutated neurons near mutation-carrying neurons, which proved to be less excitable than nonmutated neurons. Interestingly, the net balance between excitatory and inhibitory synaptic inputs onto mutated neurons remained unchanged. Additionally, we found that inhibition of adenosine kinase, which affects adenosine metabolism and neuronal excitability, reduced the hyperexcitability of nonmutated neurons. INTERPRETATION: This study shows that neurons carrying somatic mutations in MTOR lead to focal epileptogenesis via non-cell-autonomous hyperexcitability of nearby nonmutated neurons. ANN NEUROL 2021;90:285-299.


Assuntos
Epilepsias Parciais/genética , Epilepsias Parciais/fisiopatologia , Malformações do Desenvolvimento Cortical/genética , Malformações do Desenvolvimento Cortical/fisiopatologia , Serina-Treonina Quinases TOR/genética , Adolescente , Animais , Criança , Pré-Escolar , Eletroencefalografia/métodos , Epilepsias Parciais/diagnóstico por imagem , Feminino , Humanos , Masculino , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Gravidez
19.
Ann Neurol ; 89(6): 1248-1252, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33834539

RESUMO

Brain mosaic mutations are a major cause of refractory focal epilepsies with cortical malformations such as focal cortical dysplasia, hemimegalencephaly, malformation of cortical development with oligodendroglial hyperplasia in epilepsy, and ganglioglioma. Here, we collected cerebrospinal fluid (CSF) during epilepsy surgery to search for somatic variants in cell-free DNA (cfDNA) using targeted droplet digital polymerase chain reaction. In 3 of 12 epileptic patients with known somatic mutations previously identified in brain tissue, we here provide evidence that brain mosaicism can be detected in the CSF-derived cfDNA. These findings suggest future opportunities for detecting the mutant allele driving epilepsy in CSF. ANN NEUROL 2021;89:1248-1252.


Assuntos
Encéfalo , Ácidos Nucleicos Livres/líquido cefalorraquidiano , Epilepsia Resistente a Medicamentos/genética , Adolescente , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/líquido cefalorraquidiano , Feminino , Humanos , Lactente , Masculino , Mutação
20.
Childs Nerv Syst ; 37(7): 2233-2238, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33755793

RESUMO

OBJECTIVE: To investigate the feasibility and clinical effectiveness of performing multiple burr hole surgery in pediatric moyamoya patients as a response to failed modified encephaloduroarteriosynangiosis (mEDAS). METHODS: From January 2014 to May 2018, multiple burr hole surgery (MBS) was conducted on 16 hemispheres in 12 patients as a secondary treatment following mEDAS. The male-to-female ratio was 1:2 and the average age at the time of mEDAS was 6 years old. The average patient age was 9 ± 3 years olds (range 7-17) at the time of MBS which occurred an average of 46 months after mEDAS. An average of 10 ± 1 holes (range 8-13) were made. Time-to-peak (TTP) magnetic resonance images (MRI) were taken along 20 axial cuts. Of these cuts, two consecutive cuts on the lateral ventricle were selected to calculate the average value of the region of interest (ROI). The value of the cerebellum was subtracted from the average value of two consecutive cuts. The ROI value was analyzed using a paired t test by SPSS 20 (SPSS Inc., Chicago, IL, USA). RESULTS: All 16 cases presented improvement of clinical symptoms as determined by ROI analysis of the TTP MRI images. The average ROI value was 5.03 ± 6.36 before MBS and - 15.54 ± 9.42 after MBS. The average change in the ROI value was - 20.58 ± 12.59. The ROI value decreased in all cases after MBS. Magnetic resonance angiography (MRA) also showed a positive effect on vascularization. CONCLUSION: In pediatric moyamoya patients, MBS is recommended as secondary option as a response to failed mEDAS. Its clinical effectiveness was shown by analyzing TTP images and assisted by MRA and digital subtraction angiography.


Assuntos
Revascularização Cerebral , Doença de Moyamoya , Angiografia Digital , Criança , Estudos de Viabilidade , Feminino , Humanos , Lactente , Masculino , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Trepanação
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