Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
PLoS Pathog ; 19(4): e1011316, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37058447

RESUMO

The presence of human cytomegalovirus (HCMV) in glioblastoma (GBM) and improved outcomes of GBM patients receiving therapies targeting the virus have implicated HCMV in GBM progression. However, a unifying mechanism that accounts for the contribution of HCMV to the malignant phenotype of GBM remains incompletely defined. Here we have identified SOX2, a marker of glioma stem cells (GSCs), as a key determinant of HCMV gene expression in gliomas. Our studies demonstrated that SOX2 downregulated promyelocytic leukemia (PML) and Sp100 and consequently facilitated viral gene expression by decreasing the amount of PML nuclear bodies in HCMV-infected glioma cells. Conversely, the expression of PML antagonized the effects of SOX2 on HCMV gene expression. Furthermore, this regulation of SOX2 on HCMV infection was demonstrated in a neurosphere assay of GSCs and in a murine xenograft model utilizing xenografts from patient-derived glioma tissue. In both cases, SOX2 overexpression facilitated the growth of neurospheres and xenografts implanted in immunodeficient mice. Lastly, the expression of SOX2 and HCMV immediate early 1 (IE1) protein could be correlated in tissues from glioma patients, and interestingly, elevated levels of SOX2 and IE1 were predictive of a worse clinical outcome. These studies argue that HCMV gene expression in gliomas is regulated by SOX2 through its regulation of PML expression and that targeting molecules in this SOX2-PML pathway could identify therapies for glioma treatment.


Assuntos
Glioma , Proteínas Imediatamente Precoces , Animais , Humanos , Camundongos , Citomegalovirus/fisiologia , Regulação para Baixo , Expressão Gênica , Glioma/genética , Glioma/patologia , Proteínas Imediatamente Precoces/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Front Surg ; 9: 919276, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937594

RESUMO

Background: Frontal sinus exposure is a common consequence of frontal craniotomy. Cerebrospinal fluid leakage and infection are the major postoperative complications that may occur as a result of the open frontal sinus. The successful filling of the open frontal sinus provides an approach to prevent significant complications caused by frontal sinus exposure. Objective: This article describes a new technique to reconstruct the exposed frontal sinus cavity with the combined application of gelatin sponge and a vascularized pericranial flap. Methods: A total of 140 patients underwent frontal sinus reconstruction using gelfoam and vascularized pericranial flaps from 2016 to 2021. Gelatin sponge was used to fill the frontal sinus, and a vascularized pericranial flap was used to cover the frontal sinus when the bone flap was retracted. Results: Postoperative cerebrospinal fluid leakage and infection did not occur in any patient. Conclusion: Our results validated the effectiveness of our technique in the prevention of exposed frontal sinus-related postoperative complications.

4.
Front Cell Dev Biol ; 9: 736267, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35059394

RESUMO

As a primary cause of dementia and death in older people, Alzheimer's disease (AD) has become a common problem and challenge worldwide. Abnormal accumulation of tau proteins in the brain is a hallmark pathology of AD and is closely related to the clinical progression and severity of cognitive deficits. Here, we found that overexpression of phosphatase and tensin homolog (PTEN)-induced kinase 1 (PINK1) effectively promoted the degradation of tau, thereby rescuing neuron loss, synaptic damage, and cognitive impairments in a mouse model of tauopathy with AAV-full-length human Tau (hTau) injected into the hippocampal CA1 area (hTau mice). Overexpression of PINK1 activated autophagy, and chloroquine but not MG132 reversed the PINK1-induced decrease in human Tau levels and cognitive improvement in hTau mice. Furthermore, PINK1 also ameliorated mitochondrial dysfunction induced by hTau. Taken together, our data revealed that PINK1 overexpression promoted degradation of abnormal accumulated tau via the autophagy-lysosome pathway, indicating that PINK1 may be a potential target for AD treatment.

6.
J Zhejiang Univ Sci B ; 21(2): 122-136, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115910

RESUMO

Polypyrimidine tract-binding protein 1 (PTBP1) plays an essential role in splicing and is expressed in almost all cell types in humans, unlike the other proteins of the PTBP family. PTBP1 mediates several cellular processes in certain types of cells, including the growth and differentiation of neuronal cells and activation of immune cells. Its function is regulated by various molecules, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and RNA-binding proteins. PTBP1 plays roles in various diseases, particularly in some cancers, including colorectal cancer, renal cell cancer, breast cancer, and glioma. In cancers, it acts mainly as a regulator of glycolysis, apoptosis, proliferation, tumorigenesis, invasion, and migration. The role of PTBP1 in cancer has become a popular research topic in recent years, and this research has contributed greatly to the formulation of a useful therapeutic strategy for cancer. In this review, we summarize recent findings related to PTBP1 and discuss how it regulates the development of cancer cells.


Assuntos
Processamento Alternativo , Carcinogênese , Glicólise , Ribonucleoproteínas Nucleares Heterogêneas/fisiologia , Proteína de Ligação a Regiões Ricas em Polipirimidinas/fisiologia , Ribonucleoproteínas Nucleares Heterogêneas/química , Humanos , MicroRNAs/fisiologia , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Proteína de Ligação a Regiões Ricas em Polipirimidinas/química , RNA Longo não Codificante/fisiologia
8.
World Neurosurg ; 90: 454-468, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26970477

RESUMO

OBJECTIVE: To evaluate the outcomes of 177 cases of craniopharyngioma (CP) treated via a unilateral subfrontal approach. METHODS: A total of 177 continuous microscopic surgeries were performed by the senior author (Y.X.). The tumors were divided into 6 groups using the diaphragm sellae and the third ventricle floor as the anatomic references. The preoperative, postoperative, and long-term follow-up data were analyzed to evaluate the extent of tumor resection, recurrence, and functional status. RESULTS: The subfrontal-basal approach was used in 169 (91.4%) cases. Total resection was achieved in 167 (94.4%) cases. A total of 158 patients were followed from 6 to 130 months. There were 3 perioperative and 23 delayed deaths. Twenty-two patients had tumor recurrence (12.7%). The progression-free survival was 80% at 5 years and 72% at 10 years. The overall survival was 84.0% at 2.5 years and 83.2% at 10 years. There was a significant increase of pituitary dysfunction after total resection. Neurologic function was stable in most patients. Rate of hypothalamic dysfunction and mortality were higher in patients with intraventricular CPs. Of the surviving patients, 91.8% were living independently with acceptable morbidities at the end of the study. CONCLUSIONS: Most CPs extend along the intrasellar-suprasellar-third ventricle axis. A subfrontal-basal approach is a simple, safe, and effective approach to resecting CPs extending along the vertical axis. A translamina terminalis approach is an ideal corridor to resect intraventricular CP. The benefit of radical resection remains controversial, especially for CPs involving the infundibulotuberal region.


Assuntos
Craniofaringioma/cirurgia , Microcirurgia/métodos , Procedimentos Neurocirúrgicos/métodos , Neoplasias Hipofisárias/cirurgia , Adolescente , Adulto , Criança , Craniofaringioma/diagnóstico por imagem , Craniofaringioma/patologia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/patologia , Complicações Pós-Operatórias , Qualidade de Vida , Estudos Retrospectivos , Análise de Sobrevida , Terceiro Ventrículo/diagnóstico por imagem , Terceiro Ventrículo/cirurgia , Resultado do Tratamento , Carga Tumoral , Adulto Jovem
9.
Eur J Med Chem ; 99: 82-91, 2015 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-26057705

RESUMO

A series of new phenylpropenamide derivatives containing different substituents was synthesized, characterized and evaluated for their anti-hepatitis B virus (HBV) activities. The quantitative structure-activity relationships (QSAR) of phenylpropenamide compound have been studied. The 2D-QSAR models, based on DFT and multiple linear regression analysis methods, revealed that higher values of total energy (TE) and lower entropy (S(Ó©)) enhanced the anti-HBV activities of the phenylpropenamide molecules. Predictive 3D-QSAR models were established using SYBYL multifit molecular alignment rule. The optimum models were all statistically significant with cross-validated and conventional coefficients, indicating that they were reliable enough for activity prediction.


Assuntos
Amidas/síntese química , Amidas/farmacologia , Desenho de Fármacos , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/fisiologia , Relação Quantitativa Estrutura-Atividade , Replicação Viral/efeitos dos fármacos , Amidas/química , Antivirais/síntese química , Antivirais/química , Antivirais/farmacologia , Técnicas de Química Sintética , Modelos Moleculares , Conformação Molecular
10.
Oncol Rep ; 32(5): 2104-10, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25175832

RESUMO

A number of microRNAs have been identified to be important regulators of tumorigenesis. Previous research has shown that miR-124 is abundantly expressed in normal brain tissue; however, only a few reports have focused on the biological impact of miR-124 on glioma cells, and the underlying mechanisms need to be elucidated. Therefore, we investigated the effect of miR-124a on glioma cell proliferation and invasion; furthermore, the underlying molecular mechanism was examined. The present study demonstrated that miR-124a expression was downregulated in human glioma tissues, and its expression level was negatively correlated with the pathological grade of the glioma. Restoration of miR-124a inhibited glioma cell proliferation and invasion in vitro. Furthermore, we found that miR-124a directly targeted and suppressed IQ motif containing GTPase activating protein 1 (IQGAP1), a well-known regulator of actin dynamics and cell motility. RNA interference assay showed that IQGAP1 knockdown led to downregulation of ß-catenin and downstream cyclin D1. Taken together, our study revealed that miR-124a could inhibit glioma cell proliferation and invasion by blocking the expression of the IQGAP1 gene and downstream ß-catenin and cyclin D1. This research may provide a useful molecular therapy for gliomas.


Assuntos
Glioma/patologia , MicroRNAs/genética , Proteínas Ativadoras de ras GTPase/genética , Proteínas Ativadoras de ras GTPase/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glioma/genética , Glioma/metabolismo , Humanos , Invasividade Neoplásica , beta Catenina/genética , beta Catenina/metabolismo
11.
J Clin Neurosci ; 19(12): 1700-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23084350

RESUMO

Aldehyde dehydrogenase 1 (ALDH1), a detoxifying enzyme, is a stem-like cell marker, but its expression pattern and clinical significance in astrocytoma remain unclear. In this study, we used immunohistochemical analysis to systematically investigate the expression of ALDH1 in 76 astrocytomas of different pathological grade and seven samples of normal brain tissues. We found that ALDH1 was expressed in some of the astrocytomas but was not detected in normal brain tissues. The proportion of ALDH1-expressing cells was positively correlated with the pathological grade of the astrocytomas, but not with patient age, sex or tumor size. We also collected detailed follow-up data and analyzed the correlation of ALDH1 expression with overall survival (OS) and progression-free survival (PFS) using univariate and multivariate analysis. We found that the proportion of ALDH1-positive cells was an independent prognostic factor for PFS and OS. These results show that ALDH1 is expressed in astrocytoma, and that its expression is correlated with pathological grade and patient survival.


Assuntos
Astrocitoma/enzimologia , Astrocitoma/patologia , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia , Isoenzimas/biossíntese , Retinal Desidrogenase/biossíntese , Adolescente , Adulto , Família Aldeído Desidrogenase 1 , Astrocitoma/mortalidade , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Modelos de Riscos Proporcionais , Resultado do Tratamento , Adulto Jovem
12.
Chin Med J (Engl) ; 124(15): 2269-74, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21933555

RESUMO

BACKGROUND: Pituitary adenomas are common intracranial tumors, with a rising incidence in China. Excision is a mainstay therapy for this disease, and is often carried out via transfrontal, transsphenoidal or transpterional approaches. However, few studies have systematically addressed the regional anatomy involved in these microsurgical procedures. The present study attempted to establish some key anatomic measurements relevant to pituitary adenoma resection based on cadaver and computer tomography (CT) image studies. METHODS: Head specimens from 30 randomly selected formalin-fixed adult cadavers were used for anatomical analysis. Measurements were made on the base of the skull following removal of brain structures above the pituitary gland, and on the mid-sagittal plane of the cranium. Parameters were designed by considering the 3 above-mentioned common microsurgical approaches, and obtained on each head using a sliding caliper. Multi-level CT images from 30 individuals were also used for distance measurements between landmark structures that are relevant to these surgeries. All data were subjected to statistical analysis using the SPSS 11.5 software. RESULTS: There was statistically significant difference (P < 0.05) of distance measured on cadavers relative to CT images in 3 sets of measurements related to the transfrontal surgical approach, i.e., distances from the midpoint of superciliary arch superior border to the cranial entrance of internal carotid arteries (ICAs), the opposite side entrance of ICA and to the genu of ICA. While regional anatomical analyses were carried out according to the transpterional approach, statistically significant difference was also found in 3 sets of distance measurements between cadaver and CT image data, with regard to the distances between the pterion and some landmark structures around the pituitary. CONCLUSIONS: The present study provides key anatomical and CT image measurements involving the 3 conventionally used surgical approaches for pituitary tumor resection. The data implicate that while CT scan results can provide valuable guidelines for operations, cautions and adjustments are needed during surgery for sufficient tumor excision and protection of key blood vessels and nerves in the vicinity of the pituitary gland and around the surgical pathway.


Assuntos
Hipófise/anatomia & histologia , Neoplasias Hipofisárias/cirurgia , Adulto , Feminino , Humanos , Masculino , Hipófise/diagnóstico por imagem , Neoplasias Hipofisárias/diagnóstico por imagem , Radiografia
13.
Zhonghua Yi Xue Za Zhi ; 88(33): 2321-5, 2008 Aug 26.
Artigo em Chinês | MEDLINE | ID: mdl-19087691

RESUMO

OBJECTIVE: To provide pertinent anatomic data and details for the clinical application of the extended transsphenoidal approach; to probe the anatomic characteristic and method under endoscope; METHODS: 25 adult cadaver heads fixed in formalin were used to dissect, observe, measure and photograph the relationship between the neural and vascular structure and the important anatomic landmarks related to the extended transsphenoidal approach under endoscope. RESULTS: The posterior and lateral wall of sphenoidal sinus could be well exposed by bilateral approach under endoscope. The clinical application of endoscope could improve the illumination of the operative field, magnify the objects and provide two-dimensional images. The distortion of the images under endoscope depended upon the distance between the lens and the object as well as the angle of the lens. To establish the anatomic vertical compartment under the endoscope might be helpful to the operation. The midline vertical compartment consisted of the planum sphenoidale, tuberculum sella, sella and clival indentation. The paramedian vertical compartment was composed of the medial third of the optic canal and the carotid artery protuberance. The lateral vertical compartment contained four bony protuberances (optic, cavernous sinus apex, maxillary, and mandibular). Endoscopic surgical maneuvering was under non-midline direction. Precise surgical landmarks are essential for a successful operation. These landmarks allowed the surgeon to recognize and approach the surgical target without confusion. The nasopharynx, middle turbinate, and inferior turbinate were some of the landmarks in the nasal cavity. Once the sphenoidal sinus was entered, the anatomic structures of the sphenoidal sinus posterior wall, which were described above, were the unique landmarks that will guide the surgeon to the surgical target. CONCLUSION: The anatomic characteristics under endoscope were different from those under microscope. The application of the extended transsphenoidal approach under endoscope could provide more extensive vision and satisfied exposure to reach the area of the central skull base.


Assuntos
Endoscopia , Seio Esfenoidal/anatomia & histologia , Seio Esfenoidal/cirurgia , Adulto , Povo Asiático , Seio Cavernoso/anatomia & histologia , Fossa Craniana Posterior/anatomia & histologia , Humanos
14.
Acta Biochim Biophys Sin (Shanghai) ; 37(1): 68-73, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15645084

RESUMO

Human embryonic stem (hES) cells have the capability of unlimited undifferentiated proliferation, yet maintain the potential to form perhaps any cell type in the body. Based on the high efficiency of the Epstein-Barr virus-based episomal vector in introducing exogenous genes of interest into mammalian cells, we applied this system to hES cells, expecting that this would resolve the problem of poor transfection efficiency existing in current hES cell research. Therefore, the first step was to establish EBNA1-positive hES cells. Using the Fugene 6 transfection reagent, we transfected hES cells with the EBNA1 expression vector and subsequently generated hES cell clones that stably expressed EBNA1 under drug selection. These clones were confirmed to express EBNA1 mRNA by RT-PCR and to express EBNA1 protein by Western blotting. Furthermore, luciferase reporter gene analysis was performed on the EBNA1 clones and revealed that the expressed EBNA1 protein was functional. When the EBNA1-positive cells were injected into severe combined immunodeficient (SCID) mice, they formed teratoma tissues containing all three embryonic germ layers and EBNA1 protein was detected in these teratoma tissues by Western blotting. All the results show that we have successfully created stable EBNA1-hES cells, thus laying a good foundation for further research.


Assuntos
Embrião de Mamíferos/citologia , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Técnicas de Transferência de Genes , Herpesvirus Humano 4/metabolismo , Células-Tronco/citologia , Animais , Western Blotting , Diferenciação Celular , Linhagem Celular , Núcleo Celular/metabolismo , Colágeno/metabolismo , Citoplasma/metabolismo , DNA Complementar/metabolismo , Combinação de Medicamentos , Genes Reporter , Humanos , Laminina/metabolismo , Luciferases/metabolismo , Camundongos , Camundongos SCID , Plasmídeos/metabolismo , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Proteoglicanas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...