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1.
Molecules ; 21(11)2016 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-27869685

RESUMEN

The crystallized ligands in the Protein Data Bank (PDB) can be treated as the inverse shapes of the active sites of corresponding proteins. Therefore, the shape similarity between a molecule and PDB ligands indicated the possibility of the molecule to bind with the targets. In this paper, we proposed a shape similarity profile that can be used as a molecular descriptor for ligand-based virtual screening. First, through three-dimensional (3D) structural clustering, 300 diverse ligands were extracted from the druggable protein-ligand database, sc-PDB. Then, each of the molecules under scrutiny was flexibly superimposed onto the 300 ligands. Superimpositions were scored by shape overlap and property similarity, producing a 300 dimensional similarity array termed the "Three-Dimensional Biologically Relevant Spectrum (BRS-3D)". Finally, quantitative or discriminant models were developed with the 300 dimensional descriptor using machine learning methods (support vector machine). The effectiveness of this approach was evaluated using 42 benchmark data sets from the G protein-coupled receptor (GPCR) ligand library and the GPCR decoy database (GLL/GDD). We compared the performance of BRS-3D with other 2D and 3D state-of-the-art molecular descriptors. The results showed that models built with BRS-3D performed best for most GLL/GDD data sets. We also applied BRS-3D in histone deacetylase 1 inhibitors screening and GPCR subtype selectivity prediction. The advantages and disadvantages of this approach are discussed.


Asunto(s)
Bases de Datos de Proteínas , Simulación por Computador , Descubrimiento de Drogas , Humanos , Ligandos , Modelos Moleculares , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Receptores Acoplados a Proteínas G/química , Homología Estructural de Proteína , Máquina de Vectores de Soporte
2.
J Chem Inf Model ; 53(11): 2820-8, 2013 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-24125686

RESUMEN

Both recent studies and our calculation suggest that the physicochemical properties of launched drugs changed continuously over the past decades. Besides shifting of commonly used properties, the average biological relevance (BR) and similarity to natural products (NPs) of launched drugs decreased, reflecting the fact that current drug discovery deviated away from NPs. To change the current situation characterized by high investment but low productivity in drug discovery, efforts should be made to improve the BR of the screening library and hunt drugs more effectively in the biologically relevant chemical space. Additionally, a multiple dimensional molecular descriptor, named the biologically relevant spectrum (BRS) was proposed for quantitative structure-activity relationships (QSAR) study or screening library preparation. Prediction models for 43 biological activity categories were developed with BRS and support vector machine (SVM). In most cases, the overall prediction accuracies were around 95% and the Matthew's correlation coefficients (MCC) were over 0.8. Thirty-seven out of 48 drug-activity associations were successfully predicted for drugs that launched from 2006 to 2012, which were not included in the training data set. A web-server named BioRel ( http://ibi.hzau.edu.cn/biorel ) was developed to provide services including BR, BRS calculation, activity class, and pharmacokinetic property prediction.


Asunto(s)
Minería de Datos , Diseño de Fármacos , Descubrimiento de Drogas/estadística & datos numéricos , Programas Informáticos , Máquina de Vectores de Soporte , Productos Biológicos , Ensayos Clínicos como Asunto , Bases de Datos Factuales , Bases de Datos Farmacéuticas , Descubrimiento de Drogas/tendencias , Humanos , Modelos Moleculares , Relación Estructura-Actividad Cuantitativa
3.
Zhonghua Wai Ke Za Zhi ; 51(12): 1099-103, 2013 Dec.
Artículo en Zh | MEDLINE | ID: mdl-24499720

RESUMEN

OBJECTIVE: To investigate the techniques and effect of extradural approach for the resection of trigeminal schwannomas involving the cavernous sinus. METHODS: Twenty-three patients (range 26-63 years, mean age 46.2 years) with trigeminal schwannomas involving the cavernous sinus treated by middle fossa extradural approach were retrospectively analyzed. Frontotemporal orbitozygomatic extradural approach was performed in 2 patients. Frontotemporal zygomatic extradural approach was carried out in 21 patients. The first follow-up visit was on the 3rd month after surgery, and if residual was observed on enhanced MRI, then the patient was followed up every 6 months; otherwise, the patient was followed up every 8-12 months. RESULTS: The length of hospital stay after surgery was 7-13 days (mean 8.5 days). Two tumors originated from the ophthalmic branch, 2 from the maxillary branch, 5 from the mandibular branch and 14 from the gasserian ganglion. Total resection was achieved in 21 of the 23 patients (91.3%) and subtotal resection in the other 2 patients. All the patients were followed up from 3 months to 4 years. Median follow-up time was 19 months. The most common symptom was facial hypoesthesia, occurring in 18 patients. This symptom improved in 10 patients and worsened in 8 patients after surgery. New postoperative facial hypoesthesia was observed in 2 patients. Facial pain was observed in 3 patients and subsided after surgery. Two patients had loss of hearing, this symptom improved in 1 patient and worsened in 1 patient after surgery. Diplopia was observed in 6 patients. In 1 of these 6 patients, diplopia resulted from palsy of the oculomotor nerve. In the other 5 patients, diplopia resulted from palsy of the abducens nerve. This symptom improved postoperatively in all these 6 patients. New postoperative atrophy of the temporalis muscle was observed in 3 patients. There was no operation-related mortality. Tumor recurrence was only found in 1 patient after 24 months and was treated by Gamma knife. CONCLUSIONS: The middle fossa extradural approach may be an ideal option for the resection of trigeminal schwannomas involving the cavernous sinus. This approach produces no further impairment, less complication, and is less likely to injured the trigeminal nerve, abducens nerve, trochlear nerve and internal carotid artery.


Asunto(s)
Neoplasias de los Nervios Craneales/cirugía , Neurilemoma/cirugía , Procedimientos Neuroquirúrgicos/métodos , Enfermedades del Nervio Trigémino/cirugía , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
4.
Chem Asian J ; 17(2): e202101365, 2022 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-34904381

RESUMEN

The azepine- and oxepine-embedded polycyclic aromatic hydrocarbons (PAH) 1-3, as the hexa-peri-hexabenzocoronene (HBC)-based nanographenes (NG) were designed and synthesized by Diels-Alder reaction of cyclic alkene with tetrachlorothiophene-S,S-dioxide, followed by Suzuki-Miyaura cross-coupling and Scholl-type cyclodehydrogenation. Due to the strained seven-membered ring and the inherent structural pattern, heteroatom-doped NGs 1-3 show Cs symmetrical, double saddle-helix hybrid conformation, which represents a new shape for HBC based nanographenes. The calculation studies reveal the low aromaticity of the 8π heterocycles themselves and the heterocycles also decrease the electron delocalization of benzenes surrounding them. Dynamics-based calculation suggests the Cs symmetry would maintain druing the saddle-inversion process. Meanwhile, we show property perturbation by doping with different heteroatoms.


Asunto(s)
Electrones , Oxepinas , Azepinas , Reacción de Cicloadición , Conformación Molecular
5.
World J Stem Cells ; 12(12): 1439-1454, 2020 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-33505594

RESUMEN

Cancer stem-like cells (CSCs) with potential of self-renewal drive tumorigenesis. Brain tumor microenvironment (TME) has been identified as a critical regulator of malignancy progression. Many researchers are searching new ways to characterize tumors with the goal of predicting how they respond to treatment. Here, we describe the striking parallels between normal stem cells and CSCs. We review the microenvironmental aspects of brain tumors, in particular composition and vital roles of immune cells infiltrating glioma and medulloblastoma. By highlighting that CSCs cooperate with TME via various cellular communication approaches, we discuss the recent advances in therapeutic strategies targeting the components of TME. Identification of the complex and interconnected factors can facilitate the development of promising treatments for these deadly malignancies.

6.
Chin Med J (Engl) ; 133(20): 2437-2443, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-32925290

RESUMEN

BACKGROUND: Epithelial to mesenchymal transition (EMT) is strongly linked with tumor invasion and metastasis, which performs a vital role in carcinogenesis and cancer progression. Emerging evidence suggests that microRNAs (miRNAs) expression are closely associated to EMT by regulating targeted genes. MiR542 has been found to be involved in the EMT program and bound up with various cancers. However, the functions of miR542 and its underlying mechanism in glioblastoma multiforme (GBM) remain largely unknown. In the current study, we investigated the effect of astrocyte elevated gene-1 (AEG-1) on U251 cells aggressiveness, proliferation, apoptosis, and cell cycle. METHODS: The screening of targeted miRNAs was performed, as well as the functional roles and mechanisms of miR542 were explored. RESULTS: MiR542 was selected as the target because of the most significantly differential expression and this high level of expression negatively correlated with cell migration and proliferation, which suggested that miR542 could be a novel tumor suppressor. Moreover, we confirmed that AEG-1 was a direct targeted gene of miR542 by luciferase activity assay, reverse transcription-polymerase chain reaction, and immunoblotting analysis. Furthermore, miR542 suppressed the expression of AEG-1, which upgraded the level of E-cadherin and degraded Vimentin expression contributing to retraining EMT. CONCLUSION: The in vitro findings demonstrated that miR542 inhibited the migration and proliferation of U251 cells and suppressed EMT through targeting AEG-1, indicating that miR542 may be a potential anti-cancer target for GBM.


Asunto(s)
Glioblastoma , MicroARNs , Astrocitos , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Humanos , Proteínas de la Membrana , MicroARNs/genética , Invasividad Neoplásica/genética , Proteínas de Unión al ARN
7.
Neuro Oncol ; 22(12): 1797-1808, 2020 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-32492707

RESUMEN

BACKGROUND: Glioblastoma stem cells (GSCs) are a subpopulation of glioblastoma (GBM) cells that are critical for tumor invasion and treatment resistance. However, little is known about the function and mechanism of tripartite motif-containing 24 (TRIM24) in GSCs. METHODS: Immunofluorescence, flow cytometry, and western blot analyses were used to evaluate TRIM24 and cluster of differentiation (CD)133 expression profiles in GBM surgical specimens and GSC tumorspheres. Different TRIM24 expression levels in patients' tumors, as measured by both immunohistochemistry and western blot, were related to their corresponding MRI data. Wound healing, Matrigel invasion, and xenograft immunohistochemistry were conducted to determine GBM cell invasion. RESULTS: We identified that TRIM24 was coexpressed with CD133 and Nestin in GBM tissues and tumorsphere cells. Limiting dilution assays and xenotransplantation experiments illustrated that knockdown of TRIM24 expression reduced GSC self-renewal capacity and invasive growth. TRIM24 expression levels were positively associated with the volumes of peritumoral T2 weighted image abnormality. Rescue experiments indicated TRIM24 participation in GBM infiltrative dissemination. Chromatin immunoprecipitation, reporter gene assay, PCR, western blot, and immunohistochemistry demonstrated that TRIM24 activated the expression of the pluripotency transcription factor sex determining region Y-box 2 (Sox2) to regulate GBM stemness and invasion in vitro and in vivo. Finally, the close relationship between TRIM24 and Sox2 was validated by testing samples enrolled in our study and exploring external databases. CONCLUSIONS: Our findings uncover essential roles of the TRIM24-Sox2 axis in GBM stemness and invasiveness, suggesting TRIM24 as a potential target for effective GBM management.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/genética , Proteínas Portadoras , Diferenciación Celular , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Humanos , Células Madre Neoplásicas , Factores de Transcripción SOXB1/genética
8.
Zhongguo Yi Liao Qi Xie Za Zhi ; 33(3): 200-1, 2009 Mar.
Artículo en Zh | MEDLINE | ID: mdl-19771896

RESUMEN

This paper describes the principle of detector for pulse and fill-liquid in one body, which is used to detect the body pulse and the number of liquid-drop within one minute when filling liquid. The detector works exactly and rapidly. It makes doctors and nurses disentangle from the annoyed daily grinds.


Asunto(s)
Infusiones Parenterales/instrumentación , Pulso Arterial , Diseño de Equipo , Reología
9.
Medicine (Baltimore) ; 97(24): e10840, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29901576

RESUMEN

The aim of the study was to explore anterior interhemispheric approach microsurgery for removing large sellar region tumors.A total of 118 patients with large sellar region tumors were treated with the anterior interhemispheric approach microsurgery. There were 58 craniopharyngioma, 37 pituitary adenoma, 5 hypothalamic glioma, 7 meningioma, and 11 other tumors cases. The maximal tumor diameter ranged from 3.0 to 8.2 cm, with a mean diameter of 4.3 cm. Diabetes insipidus and fluid and electrolyte imbalance were timely controlled after surgery. Postoperative examination of endocrine and of magnetic resonance imaging (MRI) enhancement scanning of the head were performed.Total, subtotal, and partial removal of tumors was, respectively, achieved in 80, 23, and 15 cases. A total of 109 patients had improved vision after surgery. During the hospital stay, 81 had diabetes insipidus, 68 had fluid and electrolyte imbalance, and 9 had hemorrhage and tumidness in the right frontal lobe (3 had frontal lobe contusion, and 6 had frontal lobe hematoma). The postoperative follow-up visit lasted for 3 to 105 months. During the follow-up period, 14 patients had recurrence of tumors, 38 cases had their single or multiple pituitary axis treated with hormonal replacement therapy for a long time after surgery, and 23 cases had to orally take drugs for the purpose of controlling diabetes insipidus.The anterior interhemispheric approach microsurgery is feasible for removing large sellar region tumors without significant sequels. Active postoperative managements of diabetes insipidus and fluid and electrolyte imbalance may help patients with earlier recovery.


Asunto(s)
Microcirugia/métodos , Procedimientos Neuroquirúrgicos/métodos , Neoplasias Hipofisarias/cirugía , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Microcirugia/efectos adversos , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/efectos adversos , Hipófisis/patología , Hipófisis/cirugía , Neoplasias Hipofisarias/patología , Complicaciones Posoperatorias/epidemiología , Silla Turca/patología , Silla Turca/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven
10.
Medicine (Baltimore) ; 97(34): e11746, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30142761

RESUMEN

This study aimed to summarize the clinical experiences and postoperative effects of microsurgical approaches for craniopharyngioma.A total of 183 craniopharyngioma patients who underwent microsurgical treatment since March 2009 to March 2015 in our hospital were included in current research. Surgical approaches were selected based on preoperative evaluations, including tumor locations, sizes, and growth patterns. Active measurements to manage water-electrolyte disorder and insipidus were taken for postoperative treatments. During the follow-up, patients were monitored for residual or recurrent tumor by postoperative contrast MRI scans done 1 to 3 months after surgery.The used surgical approaches were as follows: frontopterional approach (76 cases), anterior interhemispheric approach (58 cases), transcallosal approach (10 cases), transsphenoidal approach (15 cases), unilateral subfrontal approach (15 cases), and combined approaches (9 cases). Around 124 cases (72.7%) received total tumor resection, 37 patients (20.2%) underwent subtotal resection, and 13 patients (7.1%) underwent partial removal. No significant difference was found on the postoperative complications among the different microsurgical approaches (all, P > .05). A total of 111 cases had an intact pituitary stalk preservation and 26 cases had partially preserved stalks during surgery. Visual improvement was achieved in 54 patients and visual deterioration occurred in 22 cases. Postoperative insipidus appeared in 114 cases and water-electrolyte disorder occurred in 99 cases. The postsurgical follow-up ranged from 3 to 69 months with a mean duration of 27.3 months and 23 patients suffered recurrence.Based on careful preoperative evaluation, microsurgical treatments may be safe and effective approach to improve postoperative outcomes of craniopharyngioma patients.


Asunto(s)
Craneofaringioma/cirugía , Procedimientos Neuroquirúrgicos/métodos , Neoplasias Hipofisarias/cirugía , Adolescente , Adulto , Anciano , Niño , Preescolar , Craneofaringioma/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Microcirugia , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/efectos adversos , Procedimientos Neuroquirúrgicos/clasificación , Neoplasias Hipofisarias/diagnóstico por imagen , Complicaciones Posoperatorias/clasificación , Complicaciones Posoperatorias/epidemiología , Resultado del Tratamiento , Adulto Joven
11.
Chem Biol Drug Des ; 88(6): 859-872, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27390270

RESUMEN

We applied a novel molecular descriptor, three-dimensional biologically relevant spectrum (BRS-3D), in subtype selectivity prediction of dopamine receptor (DR) ligands. BRS-3D is a shape similarity profile calculated by superimposing the objective compounds against 300 template ligands from sc-PDB. First, we constructed five subtype selectivity regression models between DR subtypes D1-D2, D1-D3, D2-D3, D2-D4, and D3-D4. The models' 10-fold cross-validation-squared correlation coefficient (Q2 , for training sets) and determination coefficient (R2 , for test sets) were in the range of 0.5-0.7 and 0.6-0.8, respectively. Then, four pair-wise (D1-D2, D2-D3, D2-D4, and D3-D4) and a multitype (D2, D3, and D4) classification models were developed with the prediction accuracies around or over 90% (for test sets). Lastly, we compared the performances of the models developed on BRS-3D and classical descriptors. The results showed that BRS-3D performed similarly to classical 2D descriptors and better than other 3D descriptors. Combining BRS-3D and 2D descriptors can further improve the prediction performance. These results confirmed the capacity of BRS-3D in the prediction of DR subtype-selective ligands.


Asunto(s)
Receptores Dopaminérgicos/metabolismo , Ligandos , Modelos Químicos , Relación Estructura-Actividad Cuantitativa , Receptores Dopaminérgicos/clasificación , Máquina de Vectores de Soporte
12.
Int J Clin Exp Med ; 8(1): 155-63, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25784984

RESUMEN

Despite the low incidence of brain abscesses in Western nations (1-2%), the incidence in developing countries is as high as 8%. We evaluate a minimally invasive image-guided keyhole aspiration of cerebral abscesses and compare it with a series of cases treated with surgical excision. 23 patients (20 male and 3 female, aged 7-67 years) underwent image-guided burr hole aspiration of single or multiple cerebral abscesses. Patient characteristics, perioperative, and postoperative data were analyzed and compared with a second group of 22 patients (14 male and 8 female, aged 12-72) treated for cerebral abscesses with open surgical excision. In all cases, the surgical procedure was performed successfully without complication. 8 of the 23 aspiration cases were performed with the aid of iMRI. A comparison of patient demographics, duration of hospital stay, duration of antibiotic therapy, postoperative neurological recovery time, intraoperative blood loss, operative duration, length of incision, postoperative fever, repeat surgery, and mortality was performed between the aspiration and excision groups. Intraoperative blood loss, operative duration, length of incision, and postoperative fever were all significantly reduced in the aspiration group. Though, duration of hospital stay and antibiotic therapy and postoperative neurological recovery time were all increased in the aspiration group, and statistical significance was observed in all except the duration of hospital stay. This technique is a feasible and comparable minimally invasive alternative to open surgical excision and may provide reduced intraoperative blood loss, shortened operative duration, improved cosmetic outcomes, and a lessened incidence of postoperative fever.

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