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1.
Chemistry ; : e202400153, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566460

RESUMEN

This paper presents a green and efficient aqueous-phase method for the synthesis of thiosulfonates, which has the benefits of no need for catalysts or redox reagents and a short reaction time, providing a method with great economic value for synthesizing thiosulfonates. Furthermore, 3-Sulfenylindoles can be easily synthesized using this method, which expands the potential applications of this reaction.

2.
Brain Behav ; 13(7): e3059, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37309087

RESUMEN

BACKGROUND AND PURPOSE: According to the classic cognitive behavioral theory proposes, dysfunctional goal-directed and habit control systems are considered central to the pathogenesis of dependent behavior and impair recovery from addictions. The functional connectivity (FC) of the brain circuits for goal-directed or habitual behavior has not been clearly reported in tobacco-dependent groups. Smoking is one of the factors in the formation of atherosclerosis. Studies have shown that the thickness of carotid intima-media (cIMT) is associated with attention-executive-psychomotor functioning. Therefore, we hypothesized whether cIMT in tobacco-dependent individuals is associated with changes in the FC of the dual-system network. METHODS: A total of 29 male tobacco-dependent subjects (tobacco-dependent group) (mean age: 64.20 years, standard deviation [SD]: 4.81 years) underwent resting-state functional magnetic resonance imaging (rs-fMRI). Exactly 28 male nonsmokers (control group) (mean age: 61.95 years, SD: 5.52 years) were also recruited to undergo rs-fMRI. We used the dorsolateral striatum (putamen) and dorsomedial striatum (caudate) as regions of interest for whole-brain resting-state connectivity to construct habitual and goal-directed brain networks, respectively. In addition, all participants were evaluated by carotid artery ultrasound to obtain the cIMT values. Then, we compared the dual-system brain networks between the tobacco dependence and control groups and the relationship between cIMT and imbalance of dual-system brain networks in tobacco dependence. RESULTS: The results showed a reduction in the connection between the caudate and precuneus and an increased connection between the putamen and prefrontal cortex; and supplementary motor area. The bilateral connectivity between the caudate and inferior frontal gyrus showed a significant negative correlation with the cIMT, and no positive correlation was observed with cIMT in the brain region that connects to the caudate. However, for the putamen, increased connectivity with the inferior temporal and medial frontal gyri was strongly associated with a high cIMT. CONCLUSIONS: The results indicate that the formation of tobacco dependence behavior is related to changes in the dual-system brain network. Carotid sclerosis is associated with the weakening of the goal-directed network and enhancement of the habit network in tobacco dependence. This finding suggests that tobacco dependence behavior and clinical vascular diseases are related to changes in brain functional networks.


Asunto(s)
Grosor Intima-Media Carotídeo , Tabaquismo , Humanos , Masculino , Persona de Mediana Edad , Imagen por Resonancia Magnética/métodos , Tabaquismo/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Mapeo Encefálico
3.
Thorac Cancer ; 12(23): 3130-3140, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34713592

RESUMEN

BACKGROUND: To develop and validate a risk prediction nomogram based on a deep learning convolutional neural networks (CNN) model and epidemiological characteristics for lung cancer screening in patients with small pulmonary nodules (SPN). METHODS: This study included three data sets. First, a CNN model was developed and tested on data set 1. Then, a hybrid prediction model was developed on data set 2 by multivariable binary logistic regression analysis. We combined the CNN model score and the selected epidemiological risk factors, and a risk prediction nomogram was presented. An independent multicenter cohort was used for model external validation. The performance of the nomogram was assessed with respect to its calibration and discrimination. RESULTS: The final hybrid model included the CNN model score and the screened risk factors included age, gender, smoking status and family history of cancer. The nomogram showed good discrimination and calibration with an area under the curve (AUC) of 91.6% (95% CI: 89.4%-93.5%), compare with the CNN model, the improvement was significance. The performance of the nomogram still showed good discrimination and good calibration in the multicenter validation cohort, with an AUC of 88.3% (95% CI: 83.1%-92.3%). CONCLUSIONS: Our study showed that epidemiological characteristics should be considered in lung cancer screening, which can significantly improve the efficiency of the artificial intelligence (AI) model alone. We combined the CNN model score with Asian lung cancer epidemiological characteristics to develop a new nomogram to facilitate and accurately perform individualized lung cancer screening, especially for Asians.


Asunto(s)
Inteligencia Artificial , Detección Precoz del Cáncer/normas , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiología , Nomogramas , Anciano , China/epidemiología , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Redes Neurales de la Computación , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X
4.
Biomed Res Int ; 2021: 5519144, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33884262

RESUMEN

OBJECTIVES: To explore the application of computed tomography (CT) texture analysis in differentiating lymphomas from other malignancies of the small bowel. METHODS: Arterial and venous CT images of 87 patients with small bowel malignancies were retrospectively analyzed. The subjective radiological features were evaluated by the two radiologists with a consensus agreement. The region of interest (ROI) was manually delineated along the edge of the lesion on the largest slice, and a total of 402 quantified features were extracted automatically from AK software. The inter- and intrareader reproducibility was evaluated to select highly reproductive features. The univariate analysis and minimum redundancy maximum relevance (mRMR) algorithm were applied to select the feature subsets with high correlation and low redundancy. The multivariate logistic regression analysis based on texture features and radiological features was employed to construct predictive models for identification of small bowel lymphoma. The diagnostic performance of multivariate models was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS: The clinical data (age, melena, and abdominal pain) and radiological features (location, shape, margin, dilated lumen, intussusception, enhancement level, adjacent peritoneum, and locoregional lymph node) differed significantly between the nonlymphoma group and lymphoma group (p < 0.05). The areas under the ROC curve of the clinical model, arterial texture model, and venous texture model were 0.93, 0.92, and 0.87, respectively. CONCLUSION: The arterial texture model showed a great diagnostic value and fitted performance in preoperatively discriminating lymphoma from nonlymphoma of the small bowel.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Neoplasias Intestinales/diagnóstico por imagen , Neoplasias Intestinales/cirugía , Intestino Delgado/diagnóstico por imagen , Intestino Delgado/patología , Linfoma/diagnóstico por imagen , Linfoma/cirugía , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Intestinales/patología , Modelos Logísticos , Linfoma/patología , Masculino , Persona de Mediana Edad , Modelos Biológicos , Análisis Multivariante , Cuidados Preoperatorios , Adulto Joven
6.
Neuropsychiatr Dis Treat ; 17: 3753-3768, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34984003

RESUMEN

INTRODUCTION: We studied the regulatory mechanism of the habitual brain network in tobacco dependence to provide a theoretical basis for the regulation and cessation of tobacco dependence. METHODS: We used resting-state functional magnetic resonance imaging (rs-fMRI) to explore the Fractional amplitude of low-frequency fluctuations (fALFF) and functional connectivity (FC) of the habitual brain network in tobacco-dependent subjects and to evaluate the relationship between the FC level and tobacco selection preference behavior. In total, 29 male tobacco-dependent participants and 28 male nonsmoking participants were recruited. rs-fMRI was used to collect blood oxygen level-dependent signals of the participants in the resting and awake states. After rs-fMRI, all subjects completed cigarette/coin selection tasks (task 1 and task 2). RESULTS: Compared with the control group, the tobacco dependence group showed increased fractional amplitude values of fALFF in the left posterior cingulate cortex and right parahippocampus. FC in the tobacco-dependent group was increased in the right inferior temporal gyrus, left middle frontal gyrus, left cingulated gyrus, and bilateral superior frontal gyrus, compared with that in the control group. Moreover, the preference selection behavior was associated with the enhancement of FC about parts of the brain regions in the habitual brain network of the tobacco-dependent participants. Thus, habitual network activity was significantly enhanced in tobacco-dependent participants in the resting state. Moreover, a positive correlation was found between the cigarette selection preference of the smokers and certain brain regions related to the habitual network. DISCUSSION: This suggests that increased activity of the habitual brain network may be essential in the development of tobacco-dependent behavior.

7.
BMC Med Imaging ; 20(1): 122, 2020 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-33138781

RESUMEN

BACKGROUND: To investigate the clinical value of CT-guided percutaneous fine-needle aspiration biopsy for peritoneal lesions of unknown nature. METHODS: A retrospective analysis was conducted of 84 patients with peritoneal thickening for unknown reasons. There were 26 males and 58 females who underwent CT-guided percutaneous fine-needle aspiration biopsy for peritoneal lesions. RESULT: Among these 84 patients, no definite pathologic diagnosis was made in 3 patients, who were lost to the follow-up. The accuracy rate of CT-guided percutaneous fine-needle aspiration biopsy was 95.1% (77/81). Sixty lesions were pathologically-diagnosed with malignancies (74.1%), including 55 with peritoneal metastases, 4 with malignant mesotheliomas, and 1 with a lymphoma. Twenty-four patients (33.8%) were diagnosed as benign lesions, including 11 with tuberculosis and 13 with inflammatory lesions. The complications of CT-guided percutaneous fine-needle aspiration biopsy included bleeding in 1 patient and ascites leakage in 2 patients. CONCLUSION: CT-guided percutaneous fine-needle aspiration biopsy is a safe and effective method for diagnosing peritoneal lesions.


Asunto(s)
Neoplasias Peritoneales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja Fina , Femenino , Humanos , Biopsia Guiada por Imagen , Perdida de Seguimiento , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/cirugía , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
8.
Carbohydr Polym ; 224: 115176, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31472871

RESUMEN

Weak mechanical properties, lack biocompatibility and relatively bioinert are formidable obstruct in application of bone repair materials. Multifunctional composite materials have been considered as a viable solution to this problem. Here, a new double network (DN) hydrogel was constructed by physical cross-linking of medical grade poly (vinyl alcohol) (PVA) and chitosan in KOH/urea dissolution system. The obtained hydrogel demonstrated excellent tensile strength (0.24 MPa), elongation at break (286%), and high compressive strength (0.11 MPa on the strain of 60%). Our studies showed that the prepared hydrogel had excellent biocompatibility in vitro and the introduction of hydroxyapatite (HAp) by surface mineralization imparted hydrogel the ability to induce rat bone marrow stem cells (rBMSCs) differentiation. The in vivo experiments revealed that the surface mineralized double network hydrogel significantly accelerated simultaneous regeneration of bone defects in a rabbit bone defect model. All the results indicated that this hydrogel has the potential as a bone repair material.


Asunto(s)
Huesos/efectos de los fármacos , Quitosano/química , Hidrogeles/química , Hidrogeles/farmacología , Minerales/química , Alcohol Polivinílico/química , Adsorción , Animales , Huesos/citología , Huesos/fisiología , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Fuerza Compresiva , Hidróxidos/química , Osteogénesis/efectos de los fármacos , Compuestos de Potasio/química , Conejos , Albúmina Sérica Bovina/química , Propiedades de Superficie , Resistencia a la Tracción , Ingeniería de Tejidos , Urea/química
9.
J Genet ; 982019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30945670

RESUMEN

Cupressus gigantea and C. torulosa are ecologically and economically important endemic species of the conifer family Cupressaceae on the Qinghai-Tibetan plateau. C. gigantea was previously classified as a subspecies of C. torulosa because of their similar morphological characteristics and close distribution. In this study, 401 individuals were sampled from 16 populations of the two Cupressus species. The specimens were genotyped using 10 polymorphic microsatellite loci through fluorescence polymerase chain reaction (PCR). The genetic diversity of C. gigantea and C. torulosa populations was generally low, with the highest genetic diversity detected in the population LLS of C. gigantea. Distance-based phylogenetic and principal co-ordinates analyses indicated a clear genetic structures for the 16 populations of the two Cupressus species. Moreover, Mantel test results showed indistinctive correlations between population-pairwise Fst values and geographic distances, as well as between genetic distances and geographic distances in C. gigantea and C. torulosa, respectively. AMOVA suggested that genetic variation mostly resided within populations. Sixteen naturalpopulations were evidently clustered into two major groups in the constructed neighbour-joining tree. The results demonstrated that C. gigantea and C. torulosa are different Cupressus species. The genetic information provided important theoretical references for conservation and management of the two endangered Cupressus species.


Asunto(s)
Cupressaceae/clasificación , Cupressaceae/genética , Variación Genética , Repeticiones de Microsatélite , Hojas de la Planta/genética , Filogenia , Análisis de Secuencia de ADN , Tibet
10.
Colloids Surf B Biointerfaces ; 173: 512-520, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30340179

RESUMEN

Cell adhesion was the first step of bone reconstruction. While hydroxyapatite (HA)/graphene composites had been utilized for improving the cell adhesion and bone osteogenesis, the impact of cell adhesion and HA/graphene composites, especially HA/hydrophilic graphene (HG) composites, on internal interaction force and external surface properties remained poorly understood. Here, higher stability HA/HG composites were synthesized without extra ion introduction with in situ self-assembling method. And with XRD, FT-IR, XPS and Raman analyses, the evidences of the formation of HA and the introduction of HG was clear. TEM and SEM images showed the net-like spatial structure due to the internal interaction force between HA and HG, which provided the strain stimulation for cell adhesion. Subsequently, the external surface properties of HA/HG composites demonstrated that the roughness and hydrophilic ability of HA/HG composites could be artificially regulated by increasing the content of HG. Besides, the cell proliferation rate of HA/HG composites had been investigated. Compared to the intrinsic HA, HA/5%HG possessed the higher cell proliferation rate (264.81%) and promoted the spreading and growth of MC3T3-E1 cells. Finally, the regulation mechanism between HA/HG and cell adhesion were illuminated in detail. The excellent regular behavior of HA/HG composites for cell adhesion made them promising candidates for bone reconstruction and repairing. The present work provided the reference for the design of modifiable biomaterials and offered much inspiration for the future research of bone reconstruction engineering.


Asunto(s)
Materiales Biocompatibles/farmacología , Sustitutos de Huesos/farmacología , Durapatita/farmacología , Grafito/farmacología , Osteoblastos/efectos de los fármacos , Andamios del Tejido , Animales , Materiales Biocompatibles/química , Sustitutos de Huesos/química , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Durapatita/química , Grafito/química , Interacciones Hidrofóbicas e Hidrofílicas , Ratones , Osteoblastos/citología , Osteoblastos/fisiología , Osteogénesis/efectos de los fármacos , Propiedades de Superficie , Ingeniería de Tejidos/métodos
11.
J Cancer Res Ther ; 14(7): 1509-1514, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30589031

RESUMEN

OBJECTIVE: The objective of the study is to evaluate the clinical efficacy and accuracy of coaxial biopsy puncture applied to make a diagnosis in 76 patients diagnosed with focal ground-glass density nodule (GGN). MATERIALS AND METHODS: In total, 76 patients were diagnosed with pure GGN (pGGN), 24 males and 52 females, aged (52 ± 1.2) years on average (range: 47-72 years). All patients underwent computed tomography (CT)-guided coaxial biopsy puncture to localize the position and measure the size of pGGN. The maximal diameter of the pGGN and the length of puncture needle into the lung were quantitatively measured. The diagnostic accuracy rate of CT-guided biopsy was subsequently validated by histological pathological examination. The incidence of postoperative complications was observed after biopsy. RESULTS: The pGGN diameter was measured from 5 to 45 mm, 21 mm on average. The pGGN depth ranged from 0 to 48 mm with a mean depth of 15 mm. Compared with the final diagnosis, the sensitivity, specificity, and accuracy rates of CT-guided needle aspiration biopsy in the diagnosis of pGGN were calculated as 97.3% (54/56), 85.0% (17/20), and 93.4% (71/76), respectively. Fourteen cases (18.4%) suffered from slight pneumothorax, 17 (22.4%) with mild errhysis surrounding the biopsy needle or lesions. CONCLUSION: CT-guided needle aspiration biopsy yields higher diagnostic accuracy and similar postoperative complications compared with the conventional histological diagnosis. For those undiagnosed by conventional CT scan and nontolerable of surgery, CT-guided needle aspiration biopsy serves as a safe and effective intervention.


Asunto(s)
Biopsia con Aguja , Biopsia Guiada por Imagen , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/patología , Tomografía Computarizada Espiral , Anciano , Biopsia con Aguja/métodos , Femenino , Humanos , Biopsia Guiada por Imagen/efectos adversos , Biopsia Guiada por Imagen/métodos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Nódulo Pulmonar Solitario/cirugía , Tomografía Computarizada Espiral/métodos , Carga Tumoral
12.
Exp Ther Med ; 16(6): 5305-5309, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30542487

RESUMEN

The aim of this study was to investigate the pathogenesis of lung ground-glass opacity (GGO) and the diagnostic value of computed tomography scan for lung GGO. Computed tomography (CT) images of 106 lung GGO cases were analyzed retrospectively, and the type, location, size, structure, boundaries and surrounding lung fields were evaluated. There were 12 cases of GGO with a diameter <1.0 cm, 36 cases with diameter of 1.0-1.5 cm, 25 cases with diameter of 1.6-2.0 cm, 19 cases with diameter of 2.0-2.5 cm and 14 cases with diameter of 2.5-3.0 cm. There were 20 lesions with a round shape and 68 lesions with an oval shape. There were 56 lesions with spinous processes, 18 lesions with air bronchograms and 37 lesions with surrounding pleural indentation. The diagnosis and differential diagnosis of GGO would be improved with combined CT scan and pathology results.

13.
PLoS One ; 10(1): e111054, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25559297

RESUMEN

Sophora moorcroftiana, a Leguminosae shrub species that is restricted to the arid and semi-arid regions of the Qinghai-Tibet Plateau, is an ecologically important foundation species and exhibits substantial drought tolerance in the Plateau. There are no functional genomics resources in public databases for understanding the molecular mechanism underlying the drought tolerance of S. moorcroftiana. Therefore, we performed a large-scale transcriptome sequencing of this species under drought stress using the Illumina sequencing technology. A total of 62,348,602 clean reads were obtained. The assembly of the clean reads resulted in 146,943 transcripts, including 66,026 unigenes. In the assembled sequences, 1534 transcription factors were identified and classified into 23 different common families, and 9040 SSR loci, from di- to hexa-nucleotides, whose repeat number is greater than five, were presented. In addition, we performed a gene expression profiling analysis upon dehydration treatment. The results indicated significant differences in the gene expression profiles among the control, mild stress and severe stress. In total, 4687, 5648 and 5735 genes were identified from the comparison of mild versus control, severe versus control and severe versus mild stress, respectively. Based on the differentially expressed genes, a Gene Ontology annotation analysis indicated many dehydration-relevant categories, including 'response to water 'stimulus' and 'response to water deprivation'. Meanwhile, the Kyoto Encyclopedia of Genes and Genomes pathway analysis uncovered some important pathways, such as 'metabolic pathways' and 'plant hormone signal transduction'. In addition, the expression patterns of 25 putative genes that are involved in drought tolerance resulting from quantitative real-time PCR were consistent with their transcript abundance changes as identified by RNA-seq. The globally sequenced genes covered a considerable proportion of the S. moorcroftiana transcriptome, and the expression results may be useful to further extend the knowledge on the drought tolerance of this plant species that survives under Plateau conditions.


Asunto(s)
Adaptación Fisiológica/genética , Sequías , Regulación de la Expresión Génica de las Plantas , Sophora/genética , Transcriptoma , Altitud , Análisis por Conglomerados , Ecosistema , Perfilación de la Expresión Génica/métodos , Ontología de Genes , Anotación de Secuencia Molecular , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN/métodos , Tibet
14.
Eur J Pharm Biopharm ; 82(1): 103-11, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22691417

RESUMEN

Novel biodegradable polymersomes containing an ionizable membrane were developed for efficient loading and rapid intracellular release of proteins. The polymersomes were prepared from poly(ethylene glycol)-b-poly(trimethylene carbonate) (PEG-PTMC) block copolymer derivatives containing acrylate, carboxylic acid, and amine groups along PTMC block, which are denoted as PEG-PTMC(AC), PEG-PTMC(COOH), and PEG-PTMC(NH(2)), respectively. Notably, nano-sized polymersomes (95.1-111.6nm) were formed by directly dispersing these copolymers in phosphate buffer at room temperature. Both FITC-labeled bovine serum albumin (FITC-BSA) and cytochrome C (FITC-CC) were readily loaded into PEG-PTMC(COOH) and PEG-PTMC(NH(2)) polymersomes with remarkably high loading levels. Interestingly, in vitro release studies showed that PEG-PTMC(COOH) and PEG-PTMC(NH(2)) polymersomes had pH-responsive protein release behaviors in which significantly faster protein release was observed at endosomal pH than at physiological pH. MTT assays indicated that these polymersomes had low cytotoxicity. Furthermore, confocal laser scanning microscope (CLSM) observations revealed that FITC-CC loaded polymersomes efficiently delivered proteins into MCF-7 cells following 24h incubation. Importantly, flow cytometry showed that CC-loaded polymersomes induced markedly enhanced apoptosis in MCF-7 cells as compared to free CC. These novel membrane ionizable biodegradable polymersomes have appeared as highly promising nanocarriers for efficient intracellular protein delivery.


Asunto(s)
Citocromos c/farmacología , Dioxanos/química , Sistemas de Liberación de Medicamentos , Polietilenglicoles/química , Polímeros/química , Apoptosis/efectos de los fármacos , Citocromos c/administración & dosificación , Dioxanos/toxicidad , Portadores de Fármacos/química , Portadores de Fármacos/toxicidad , Endosomas/metabolismo , Citometría de Flujo , Fluoresceína-5-Isotiocianato/química , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Células MCF-7 , Microscopía Confocal , Nanopartículas , Polietilenglicoles/toxicidad , Polímeros/toxicidad , Albúmina Sérica Bovina/administración & dosificación , Temperatura , Factores de Tiempo
16.
Biomaterials ; 31(29): 7575-85, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20599266

RESUMEN

Biodegradable chimaeric polymersomes based on asymmetric PEG-PCL-PDEA triblock copolymers were prepared and investigated for delivery of exogenous proteins into cells. PEG-PCL-PDEA copolymers with M(n)(PEG) = 5 kg/mol, M(n)(PCL) = 18.2 kg/mol, and short PDEA blocks ranging from 1.1, 2.7 to 4.1 kg/mol (denoted as copolymer 1, 2 and 3, respectively) were obtained by controlled reversible addition-fragmentation chain transfer (RAFT) polymerization. The direct hydration of copolymer thin films in MES buffer (pH 5.3) yielded uniform polymersomes with sizes of 130-175 nm. These polymersomes had close to neutral zeta potentials (-2 approximately +2.7 mV) at pH 7.4. The polymersomal structures were confirmed by confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM), and catalytic activity experiment on 3,3',3''-phosphinidyne(trisbenzenesulfonic acid)-loaded polymersomes. MTT assays showed that these polymersomes were non-toxic up to a concentration of 0.5mg/mL. These chimaeric polymersomes, in particular polymersome 2, showed remarkably high protein loading efficiencies and loading contents for bovine serum albumin (BSA), cytochrome C (CC), lysozyme (Lys), ovalbumin (OVA) and immunoglobulin G (IgG). The encapsulation of proteins did not significantly alter the polymersome size distributions and zeta potentials. The protein release studies showed that both BSA and CC were released in a controlled manner. Importantly, the released CC fully maintained its activity. Notably, CLSM studies showed that FITC-CC loaded polymersomes efficiently delivered and released proteins into the cytoplasm of RAW 264.7 cells. Moreover, these chimaeric polymersomes were able to simultaneously load and transport proteins and doxorubicin into the cytoplasm as well as the cell nucleus. We are convinced that these biodegradable chimaeric polymersomes have great potentials in protein therapy.


Asunto(s)
Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Polímeros/química , Proteínas/administración & dosificación , Proteínas/química , Acrilamidas/química , Animales , Línea Celular , Portadores de Fármacos/síntesis química , Células HeLa , Humanos , Espectroscopía de Resonancia Magnética , Ratones , Microscopía Confocal , Modelos Teóricos , Poliésteres/química , Polietilenglicoles/química , Polímeros/administración & dosificación , Polímeros/síntesis química
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 28(1): 105-9, 2006 Feb.
Artículo en Chino | MEDLINE | ID: mdl-16548202

RESUMEN

OBJECTIVE: To explore the radiological diagnosis of primary malignant fibrous histiocytoma (MFH) of bone. METHODS: Sixteen patients with biopsy-or surgery-confirmed MFH received both plain X-ray and CT examinations, among whom six patients simultaneously received MRI. The imaging features were analyzed and the differential diagnoses were assessed. RESULTS: (1) Plain X-ray findings: All these lesions showed irregularly osteolytic, accompanied by cortical destruction. Five patients had varied degrees of cortical expansion, 12 had large soft tissue masses adjacent to the lesions, and only 2 had periosteal reaction. (2) CT findings: All lesions were osteolytic areas but had no evidences that its internal architecture had been replaced by soft tissue mass, and the cortical adjacent to the lesions were permeative osteolysis. Four patients had internal or marginal crest within the lesions and marginal inconsecutive osteosclerosis. Twelve had large soft tissue masses but without any calcification and residual architecture adjacent to the lesions, among which 3 patients had solitary or multiple cystic attenuation areas within the masses. No clear periosteal reaction was observed on CT. (3) MRI findings: All of lesions in 6 patients who received MRI showed inhomogeneous long T1 and long T2 abnormal signal intensity with soft tissue masses adjacent to the osteo-destructions. CONCLUSIONS: The imaging manifestations of MFH were specific to some extent. Combined utilization of plain X-ray, CT, and MRI is helpful for the diagnosis and differential diagnosis of MFH.


Asunto(s)
Neoplasias Óseas/diagnóstico , Histiocitoma Fibroso Maligno/diagnóstico , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Adulto , Anciano , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/patología , Femenino , Histiocitoma Fibroso Maligno/diagnóstico por imagen , Histiocitoma Fibroso Maligno/patología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Película para Rayos X
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