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1.
Sci Rep ; 11(1): 6381, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33737656

RESUMO

Glioma is the most general primary and lethal intracranial malignant tumor. Pterostilbene (PTE), an analog of stilbene and resveratrol, has attracted attention in recent years due to its significant antitumor activity in multiple solid tumors; however, its effect on drug-resistant glioma cells and the underlying mechanism have not yet been reported. In this study, we found that pterostilbene inhibited proliferation, induced intrinsic mitochondria-mediated apoptosis and caused S phase arrest, inhibited migration and excessive invasion in glioma cells. Pretreatment with the pan-caspase-inhibitor Z-VAD-FMK attenuated the PTE-induced apoptosis of glioma cells. Moreover, PTE significantly increased the production of reactive oxygen species (ROS) and reduce the mitochondrial membrane potential (MMP). Inhibition of ROS with N-acetyl-L-cysteine not only rescued PTE-induced reduction of cellular viability but also prevented glioma cell apoptosis. We also discovered ERK 1/2 and JNK signaling pathways were activated by PTE and contributed to induce glioma cell apoptosis. In addition, specific inhibitors of ERK 1/2 and JNK attenuated PTE-induced apoptosis. Besides, PTE significantly reduced tumor volume and prolonged median survival of tumor-bearing rats in vivo. In summary, the results of this study indicate that the anti-tumor effect of PTE on glioma cells may provide a new treatment option for glioma patients.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glioma/tratamento farmacológico , Estilbenos/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/genética , Glioma/patologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Br J Neurosurg ; 34(2): 227-228, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29405778

RESUMO

We describe a rare case of syringomyelia with left knee Charcot arthropathy in a 35-year-old male, who presented with dissociative sensory disorder, muscle atrophy, painless knee joint swelling and limited joint mobility. Early diagnosis and appropriate treatment are essential in avoiding disease progression.


Assuntos
Artropatia Neurogênica , Siringomielia , Adulto , Malformação de Arnold-Chiari , Humanos , Joelho , Masculino
3.
World Neurosurg ; 130: 1-6, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31254713

RESUMO

BACKGROUND: Cases of multiple intracranial tumors are common; however, cases of multiple intraspinal tumors are rare. Except for cases of neurofibromatosis, it is very rare for tumors of different pathological types to exist concurrently at the same spinal level. Only 9 cases have been reported to date, with meningioma found with schwannoma in 7 cases and with neurofibroma in 2 cases. CASE DESCRIPTION: We have reported another rare case in which neurofibroma and meningioma were identified within a single dumbbell-shaped tumor at the same cervical level without neurofibromatosis. The preoperative magnetic resonance imaging findings indicated a single extra- and intradural extramedullary dumbbell-shaped neurogenic tumor on the left ventral side of the cervical spine. Intraoperatively, we found that the mass consisted of 2 pathologically different tumors. The results of surgical resection were mostly satisfactory. CONCLUSIONS: To the best of our knowledge, the present case is the first reported case of intradural neurofibroma (not meningioma) and extradural meningioma growing mixed together at the same spinal level without neurofibromatosis. The precise mechanism underlying the formation of the tumor is unknown, and multidirectional differentiation of a common progenitor cell is one possibility. Intra- and extradural exploration and component biopsies are useful for treatment planning, especially when the magnetic resonance imaging is not sufficiently sensitive for the diagnosis of coexisting tumor types.


Assuntos
Vértebras Cervicais/diagnóstico por imagem , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Neurofibroma/diagnóstico por imagem , Neurofibromatoses , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Feminino , Humanos , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/cirurgia , Meningioma/complicações , Meningioma/cirurgia , Pessoa de Meia-Idade , Neurofibroma/complicações , Neurofibroma/cirurgia , Neoplasias da Coluna Vertebral/complicações , Neoplasias da Coluna Vertebral/cirurgia
4.
J Exp Clin Cancer Res ; 37(1): 78, 2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29631594

RESUMO

BACKGROUND: Glioma is a heterogeneous, invasive primary brain tumor with a wide range of patient survival and a lack of reliable prognostic biomarkers. Human telomerase reverse transcriptase (hTERT) has been reported in the presence of multiple transcripts in various tumor systems. The biological function and precise regulatory mechanisms of hTERT transcripts remain uncertain. METHODS: Alternative splicing of hTERT and telomerase activity were examined in 96 glioma specimens, including 38 glioblastomas (GBMs), 23 oligodendrogliomas (ODMs), and 35 oligoastrocytomas (OAMs). The correlation between telomerase activity or hTERT transcripts and patient clinical characteristics was investigated. We examined the regulation of alternative splicing of hTERT and telomerase activity by G-quadruplex stabilizer CX-5461 in GBM cells. The biological effects of CX-5461 on GBM cell lines, including inhibition of cell proliferation, effects on cell cycle/apoptosis, and telomere DNA damage were further explored. RESULTS: The ß splicing was verified in human gliomas and hTERT+ß was significantly correlated with higher telomerase activity, higher KPS, larger tumor size, and higher tumor grades. Meanwhile, glioma patients lacking hTERT+ß expression or telomerase activity showed a significant survival benefit. Notably, CX-5461 altered hTERT splicing patterns, leading to an increase of hTERT-ß transcript and a decrease of hTERT+ß transcript expression, which inhibits telomerase activity. In addition, CX-5461 had cytotoxic effects on GBM cells and caused telomere DNA damage response, induced G2/M arrest and apoptosis. CONCLUSIONS: The hTERT+ß is verified to be correlated with clinical parameters in gliomas, and could serve as a prognostic marker or possibly therapeutic target for gliomas. CX-5461 can regulate the splicing pattern of hTERT, inhibit telomerase activity, and kill GBM cells.


Assuntos
Processamento Alternativo , Benzotiazóis/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/genética , Naftiridinas/farmacologia , Telomerase/genética , Adulto , Idoso , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Dano ao DNA , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Glioma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Carga Tumoral
5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(1 Pt 2): 016401, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19257142

RESUMO

The time dependence of the x-ray absorption of aluminum samples heated with intense radiation sources from a foam-buffered gold hohlraum has been studied in this work. Hydrodynamic simulations were used to illustrate the plasma conditions in the plastic-tamped aluminum foils contained in this type of hohlraum. Experiments were conducted to measure the K -shell x-ray absorption spectra of the aluminum sample. With densities taken from the hydrodynamic simulations, electron temperatures were then inferred by fitting the measured absorption spectra with detailed-term-accounting calculations. The inferred temperatures have a maximum of about 93eV and were found to agree within 25% with the simulated results at times after 1ns , indicating that the use of foam shields, together with a compact cavity, has created a clean and high-temperature radiation source preferable to opacity measurements.

6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 66(3 Pt 2B): 036410, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12366270

RESUMO

Eight beams of 0.35-microm laser with pulse duration of about 1.0 ns and energy of 260 J per beam were injected into a cylindrical cavity to generate intense x-ray radiation on the Shengguang II high power laser facility. Plastic foils with a thickness in the range of about 3.0-45 microm were attached on the diagnostic hole of the cavity and ablated by the intense x-ray radiation. The radiative energy transport through plastic foils with different thicknesses has been studied experimentally. The burn-through time of the plastic foils has been obtained. For comparison, we also simulated the experimental results with Planckian and non-Planckian x-ray spectrum source, respectively. It is shown that for thick plastic foil the simulation with non-Planckian x-ray spectrum source is in good agreement with the experiment.

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