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1.
J Neurol ; 271(3): 1256-1266, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37947856

RESUMO

OBJECTIVE: Few effective treatments improve upper extremity (UE) function after stroke. Immersive virtual reality (imVR) is a novel and promising strategy for stroke UE recovery. We assessed the extent to which imVR-based UE rehabilitation can augment conventional treatment and explored changes in brain functional connectivity (FC) that were related to the rehabilitation. METHODS: An assessor-blinded, parallel-group randomized controlled trial was performed with 40 subjects randomly assigned to either imVR or Control group (1:1 allocation), each receiving rehabilitation 5 times per week for 3 weeks. Subjects in the imVR received both imVR and conventional rehabilitation, while those in the Control received conventional rehabilitation only. Our primary and secondary outcomes were the Fugl-Meyer assessment's upper extremity subscale (FMA-UE) and the Barthel Index (BI), respectively. Both intention-to-treat (ITT) and per-protocol (PP) analyses were performed to assess the effectiveness of the trial. For both the FMA-UE/BI, a one-way analysis of covariance (ANCOVA) model was used, with the FMA-UE/BI at post-intervention or at follow-up, respectively, as the dependent variable, the two groups as the independent variable, baseline FMA-UE/BI, age, sex, site, time since onset, hypertension and diabetes as covariates. RESULTS: Both ITT and PP analyses demonstrated the effectiveness of imVR-based rehabilitation. The FMA-UE score was greater in the imVR compared with the Control at the post-intervention (mean difference: 9.1 (95% CI 1.6, 16.6); P = 0.019) and follow-up (mean difference:11.5 (95% CI 1.9, 21.0); P = 0.020). The results were consistent for BI scores. Moreover, brain FC analysis found that the motor function improvements were associated with a change in degree in ipsilesional premotor cortex and ipsilesional dorsolateral prefrontal cortex immediately following the intervention and in ipsilesional visual region and ipsilesional middle frontal gyrus after the 12-week follow-up. CONCLUSIONS: ImVR-based rehabilitation is an effective tool that can improve the recovery of UE functional capabilities of subacute stroke patients when added to standard care. These improvements were associated with distinctive brain changes at two post-stroke timepoints. The study results will benefit future patients with stroke and provide evidence for a promising new method of stroke rehabilitation. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03086889.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Realidade Virtual , Humanos , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Reabilitação do Acidente Vascular Cerebral/métodos , Encéfalo , Resultado do Tratamento , Extremidade Superior
2.
IEEE Trans Med Imaging ; PP2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38015692

RESUMO

The generation of synthetic data using physics-based modeling provides a solution to limited or lacking real-world training samples in deep learning methods for rapid quantitative magnetic resonance imaging (qMRI). However, synthetic data distribution differs from real-world data, especially under complex imaging conditions, resulting in gaps between domains and limited generalization performance in real scenarios. Recently, a single-shot qMRI method, multiple overlapping-echo detachment imaging (MOLED), was proposed, quantifying tissue transverse relaxation time (T2) in the order of milliseconds with the help of a trained network. Previous works leveraged a Bloch-based simulator to generate synthetic data for network training, which leaves the domain gap between synthetic and real-world scenarios and results in limited generalization. In this study, we proposed a T2 mapping method via MOLED from the perspective of domain adaptation, which obtained accurate mapping performance without real-label training and reduced the cost of sequence research at the same time. Experiments demonstrate that our method outshined in the restoration of MR anatomical structures.

3.
Front Neurol ; 13: 780966, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35309550

RESUMO

Stroke is a chief cause of sudden brain damage that severely disrupts the whole-brain network. However, the potential mechanisms of motor recovery after stroke are uncertain and the prognosis of poststroke upper extremity recovery is still a challenge. This study investigated the global and local topological properties of the brain functional connectome in patients with subacute ischemic stroke and their associations with the clinical measurements. A total of 57 patients, consisting of 29 left-sided and 28 right-sided stroke patients, and 32 age- and gender-matched healthy controls (HCs) were recruited to undergo a resting-state functional magnetic resonance imaging (rs-fMRI) study; patients were also clinically evaluated with the Upper Extremity Fugl-Meyer Assessment (FMA_UE). The assessment was repeated at 15 weeks to assess upper extremity functional recovery for the patient remaining in the study (12 left- 20 right-sided stroke patients). Global graph topological disruption indices of stroke patients were significantly decreased compared with HCs but these indices were not significantly associated with FMA_UE. In addition, local brain network structure of stroke patients was altered, and the altered regions were dependent on the stroke site. Significant associations between local degree and motor performance and its recovery were observed in the right lateral occipital cortex (R LOC) in the right-sided stroke patients. Our findings suggested that brain functional topologies alterations in R LOC are promising as prognostic biomarkers for right-sided subacute stroke. This cortical area might be a potential target to be further validated for non-invasive brain stimulation treatment to improve poststroke upper extremity recovery.

4.
Sci Rep ; 11(1): 11103, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045581

RESUMO

The heat shock protein 90 inhibitor, luminespib, has demonstrated potent preclinical activity against numerous cancers. However, clinical translation has been impeded by dose-limiting toxicities that have necessitated dosing schedules which have reduced therapeutic efficacy. As such, luminespib is a prime candidate for reformulation using advanced drug delivery strategies that improve tumor delivery efficiency and limit off-target side effects. Specifically, thermosensitive liposomes are proposed as a drug delivery strategy capable of delivering high concentrations of drug to the tumor in combination with other chemotherapeutic molecules. Indeed, this work establishes that luminespib exhibits synergistic activity in lung cancer in combination with standard of care drugs such as cisplatin and vinorelbine. While our research team has previously developed thermosensitive liposomes containing cisplatin or vinorelbine, this work presents the first liposomal formulation of luminespib. The physico-chemical properties and heat-triggered release of the formulation were characterized. Cytotoxicity assays were used to determine the optimal drug ratios for treatment of luminespib in combination with cisplatin or vinorelbine in non-small cell lung cancer cells. The formulation and drug combination work presented in this paper offer the potential for resuscitation of the clinical prospects of a promising anticancer agent.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Isoxazóis/administração & dosagem , Pulmão/efeitos dos fármacos , Nanomedicina , Resorcinóis/administração & dosagem , Linhagem Celular Tumoral , Temperatura Alta , Humanos , Lipossomos
5.
Pain Rep ; 6(1): e906, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33981932

RESUMO

Lumbar disc herniation (LDH) is a common back disorder that evokes back and/or leg pain. Percutaneous endoscopic lumbar discectomy (PELD) is a minimally invasive surgery for patients with LDH. However, there is little evidence of effectiveness of PELD compared with conservative treatments. OBJECTIVE: The goal of this study was to quantify the efficacy of PELD compared with conservative treatments. METHODS: Here, we conducted a prospective observational cohort study using momentary pain assessments via a smartphone app during 3 months following surgery. The trajectories of daily ecological momentary pain assessments were fitted with an exponential model containing two parameters: a pain reduction coefficient and the percentage of persistent pain. To control for selection bias between PELD and Conservative groups (N = 167 and 34), we used inverse probability (IP) of treatment weighting for statistical comparisons. RESULTS: Compared with conservative treatments, both momentary pain rating and the exponential model showed statistically significant pain recovery following PELD (p < 0.001). In addition, PELD had a faster pain recovery rate (hazard ratio (95% confidence interval): 1.75 (1.40, 2.20), p < 0.001), greater overall pain recovery rate (odds ratio (95%CI): 2.35 (2.01, 5.26), p < 0.001), faster pain reduction (t199 = 3.32, p = 0.001), and lower estimated persistent pain (Z = 2.53, p = 0.011). Greater pain intensity and lower anxiety before the surgery were predictors of faster pain reduction in the recovery subgroup following PELD. CONCLUSIONS: In conclusion, momentary pain rating and the model fitting revealed that PELD provided rapid pain recovery that lasted for at least three months. Greater pain intensity and lower anxiety before the surgery were predictors of faster pain reduction in the recovery subgroup following PELD. Daily momentary pain rating on a smartphone may be able to provide more informative data to evaluate effect of an intervention than pain assessment on hospital visits.

6.
Hum Brain Mapp ; 42(3): 713-723, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33079467

RESUMO

Head motion is a major confounding factor impairing the quality of functional magnetic resonance imaging (fMRI) data. In particular, head motion can reduce analytical efficiency, and its effects are still present even after preprocessing. To examine the validity of motion removal and to evaluate the remaining effects of motion on the quality of the preprocessed fMRI data, a new metric of group quality control (QC), dissimilarity of functional connectivity, is introduced. Here, we investigate the association between head motion, represented by mean framewise displacement, and dissimilarity of functional connectivity by applying four preprocessing methods in two independent resting-state fMRI datasets: one consisting of healthy participants (N = 167) scanned in a 3T GE-Discovery 750 with longer TR (2.5 s), and the other of chronic back pain patients (N = 143) in a 3T Siemens Magnetom Prisma scanner with shorter TR (0.555 s). We found that dissimilarity of functional connectivity uncovers the influence of participant's motion, and this relationship is independent of population, scanner, and preprocessing method. The association between motion and dissimilarity of functional connectivity, and how the removal of high-motion participants affects this association, is a new strategy for group-level QC following preprocessing.


Assuntos
Dor nas Costas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Dor Crônica/diagnóstico por imagem , Conectoma , Movimentos da Cabeça , Imageamento por Ressonância Magnética , Adulto , Dor nas Costas/fisiopatologia , Encéfalo/fisiologia , Dor Crônica/fisiopatologia , Conectoma/normas , Feminino , Humanos , Imageamento por Ressonância Magnética/normas , Masculino , Pessoa de Meia-Idade
7.
Sensors (Basel) ; 20(6)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32178235

RESUMO

Landslide susceptibility prediction (LSP) modeling is an important and challenging problem. Landslide features are generally uncorrelated or nonlinearly correlated, resulting in limited LSP performance when leveraging conventional machine learning models. In this study, a deep-learning-based model using the long short-term memory (LSTM) recurrent neural network and conditional random field (CRF) in cascade-parallel form was proposed for making LSPs based on remote sensing (RS) images and a geographic information system (GIS). The RS images are the main data sources of landslide-related environmental factors, and a GIS is used to analyze, store, and display spatial big data. The cascade-parallel LSTM-CRF consists of frequency ratio values of environmental factors in the input layers, cascade-parallel LSTM for feature extraction in the hidden layers, and cascade-parallel full connection for classification and CRF for landslide/non-landslide state modeling in the output layers. The cascade-parallel form of LSTM can extract features from different layers and merge them into concrete features. The CRF is used to calculate the energy relationship between two grid points, and the extracted features are further smoothed and optimized. As a case study, the cascade-parallel LSTM-CRF was applied to Shicheng County of Jiangxi Province in China. A total of 2709 landslide grid cells were recorded and 2709 non-landslide grid cells were randomly selected from the study area. The results show that, compared with existing main traditional machine learning algorithms, such as multilayer perception, logistic regression, and decision tree, the proposed cascade-parallel LSTM-CRF had a higher landslide prediction rate (positive predictive rate: 72.44%, negative predictive rate: 80%, total predictive rate: 75.67%). In conclusion, the proposed cascade-parallel LSTM-CRF is a novel data-driven deep learning model that overcomes the limitations of traditional machine learning algorithms and achieves promising results for making LSPs.

8.
Pain ; 160(12): 2829-2840, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408051

RESUMO

Brain functional network properties are globally disrupted in multiple musculoskeletal chronic pain conditions. Back pain with lumbar disk herniation (LDH) is highly prevalent and a major route for progression to chronic back pain. However, brain functional network properties remain unknown in such patients. Here, we examined resting-state functional magnetic resonance imaging-based functional connectivity networks in chronic back pain patients with clear evidence for LDH (LDH-chronic pain n = 146), in comparison to healthy controls (HCs, n = 165). The study was conducted in China, thus providing the opportunity to also examine the influence of culture on brain functional reorganization with chronic pain. The data were equally subdivided into discovery and validation subgroups (n = 68 LDH-chronic pain and n = 68 HC, for each subgroup), and contrasted to an off-site data set (n = 272, NITRC 1000). Graph disruption indices derived from 3 network topological measurements, degree, clustering coefficient, and efficiency, which respectively represent network hubness, segregation, and integration, were significantly decreased compared with HC, across all predefined link densities, in both discovery and validation groups. However, global mean clustering coefficient and betweenness centrality were decreased in the discovery group and showed trend in the validation group. The relationship between pain and graph disruption indices was limited to males with high education. These results deviate somewhat from recent similar analysis for other musculoskeletal chronic pain conditions, yet we cannot determine whether the differences are due to types of pain or also to cultural differences between patients studied in China and the United States.


Assuntos
Encéfalo/diagnóstico por imagem , Dor Crônica/diagnóstico por imagem , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Adulto , Dor Crônica/etiologia , Feminino , Humanos , Deslocamento do Disco Intervertebral/etiologia , Vértebras Lombares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
9.
Pain Res Manag ; 2019: 6924941, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30719201

RESUMO

Background: Both transforaminal percutaneous endoscopic lumbar discectomy with foraminoplasty (TF PELF) and transforaminal percutaneous endoscopic lumbar discectomy without foraminoplasty (TF PELD) were developed for lumbar disc herniation (LDH) patients. However, the safety and effectiveness between the TF PELF and TF PELD have not been investigated. Methods: Of the included 140 LDH patients, 62 patients received TF PELF (PELF group) and 78 patients received TF PELD (PELD group). The operation time, the duration of staying at the hospital, and complication incidences were recorded. All patients were followed up for 2 years, where low back and leg visual analogue scale (VAS) pain ratings and Oswestry Disability Index (ODI) were compared between the 2 groups before and after surgery. Modified Macnab criterion was estimated for all patients at postoperative 2 years. Results: There were no significant difference of the operation time, number of days staying at the hospital, and the incidence of complications between the 2 groups (P > 0.05). Two cases in the PELF group and 1 case in the PELD group received a second surgery due to unrelieved symptoms postoperatively. Low back and leg VAS and ODI scores decreased in both groups after operation (P < 0.01), respectively, but were not significant between the 2 groups over time (P > 0.05). Six patients in the PELF group and 3 patients in the PELD group did not continue the follow-up; thus, only 131 patients completed Macnab evaluation. The satisfactory rate was reported as 80.4% in the PELF group and 90.7% in the PELD group (P > 0.05). Conclusions: This study suggested that the safety and effectiveness of TF PELF are comparable to TF PELD for LDH patients.


Assuntos
Discotomia Percutânea/métodos , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
10.
BMC Cancer ; 8: 242, 2008 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-18706101

RESUMO

BACKGROUND: Honokiol is a major bioactive compound extracted from Magnolia. The present study was designed to determine whether liposomal honokiol has the antitumor activity against human lung cancer as well as potentiates the antitumor activity of cisplatin in A549 lung cancer xenograft model, if so, to examine the possible mechanism in the phenomenon. METHODS: human A549 lung cancer-bearing nude mice were treated with liposomal honokiol, liposomal honokiol plus DDP or with control groups. Apoptotic cells and vessels were evaluated by fluorescent in situ TUNEL assay and by immunohistochemistry with an antibody reactive to CD31 respectively. RESULTS: The present study showed that liposomal honokiol alone resulted in effective suppression of the tumor growth, and that the combined treatment with honokiol plus DDP had the enhanced inhibition of the tumor growth and resulted in a significant increase in life span. The more apparent apoptotic cells in the tumors treated with honokiol plus DDP was found in fluorescent in situ TUNEL assay, compared with the treatment with control groups. In addition, the combination of honokiol and DDP apparently reduced the number of vessels by immunolabeling of CD31 in the tissue sections, compared with control groups. CONCLUSION: In summary, our data suggest that honokiol alone had the antitumor activity against human lung cancer in A549 lung cancer xenograft model, and that the combination of honokiol with DDP can enhance the antitumor activity, and that the enhanced antitumor efficacy in vivo may in part result from the increased induction of the apoptosis and the enhanced inhibition of angiogenesis in the combined treatment. The present findings may be of importance to the further exploration of the potential application of the honokiol alone or the combined approach in the treatment of lung carcinoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Compostos de Bifenilo/farmacologia , Cisplatino/administração & dosagem , Lignanas/farmacologia , Lipossomos/química , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Animais , Apoptose , Compostos de Bifenilo/administração & dosagem , Linhagem Celular Tumoral , Humanos , Marcação In Situ das Extremidades Cortadas , Lignanas/administração & dosagem , Camundongos , Transplante de Neoplasias , Neovascularização Patológica , Extratos Vegetais/farmacologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/biossíntese
11.
Biotechnol Appl Biochem ; 48(Pt 2): 109-16, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17868025

RESUMO

CCL19 [chemokine (C-C motif) ligand 19; also known as MIP-3beta (macrophage inflammatory protein-3beta) or ELC (Epstein-Barr-virus-induced molecule 1 ligand chemokine)], one of the immunostimulatory cytokines, chemoattracts both DCs (dendritic cells) and T-lymphocytes. Adenoviral vector is one of the most used gene delivery vectors for cancer therapy because of its high gene-transfection efficiency. However, its wider application is limited, owing to immune responses that reduce transgene expression and decrease the efficacy of repeated administration. We constructed the recombinant replication deficient adenoviral vectors containing the CCL19 gene (Ad-CCL19) and combined them with PEG-PE [poly(ethylene glycol)-phosphatidylethanolamine]-modified cationic liposomes (Ad-CCL19/PEG-PE) for immunotherapy against murine fibrosarcoma. Although there were hardly any therapeutic differences between Ad-CCL19- and Ad-CCL19/PEG-PE-treated mice that were observed at the second administration, the final results demonstrated that Ad-CCL19/PEG-PE-treated mice survived much longer. The antitumour efficacy may be related to the high level of CCL19 after the final administration and lasting expression of IFN-gamma (interferon-gamma) and IL-12 (interleukin-12) in the Ad-CCL19/PEG-PE-treated group, which were measured by reverse-transcription PCR and ELISA. The results demonstrated that PEG-PE-cationic-liposome-conjugated adenovirus could prolong the expression of the therapeutic gene in vivo and may enhance the antitumour efficacy.


Assuntos
Adenoviridae/genética , Quimiocinas CC/genética , Quimiocinas CC/uso terapêutico , Marcação de Genes/métodos , Terapia Genética/métodos , Lipossomos/química , Neoplasias Pulmonares/terapia , Adenoviridae/química , Animais , Antineoplásicos/uso terapêutico , Cátions , Quimiocina CCL19 , Feminino , Vetores Genéticos/genética , Neoplasias Pulmonares/genética , Camundongos , Camundongos Endogâmicos BALB C , Transfecção/métodos , Resultado do Tratamento
12.
Anticancer Drugs ; 18(10): 1165-71, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17893517

RESUMO

Quercetin, a widely distributed bioflavonoid, inhibits the growth of various tumor cells. The present study was designed to investigate whether a novel quercetin derivative [phenylisocyanate of quercetin (PHICNQ)] exerts antitumor activity against K562 and CT26 tumor cell lines by inducing apoptosis, and to examine the possible mechanism in the phenomenon. The cell proliferation assay of K562 and CT26 tumor cells was determined by the trypan blue dye exclusion test. Apoptosis of PHICNQ-treated cells was determined by morphological analysis, agarose gel DNA electrophoresis and quantitated by flow cytometry after staining with propidium iodide. Cell cycle was evaluated by flow cytometry. The expression of heat shock protein 70 was checked by Western blot analysis. Our results showed that PHICNQ inhibited the proliferation of K562 and CT26 cells in a dose-dependent and time-dependent manner. PHICNQ was 308- and 73-fold more active on CT26 and K562 cells than quercetin, respectively. In addition to this cytostatic effect, treatment of K562 and CT26 tumor cells with PHICNQ induced apoptosis. PHICNQ treatment downregulated the expression of heat shock protein 70 more dramatically than quercetin treatment. These results suggest that PHICNQ is a more powerful antiproliferative derivative than quercetin, with cytostatic and apoptotic effects on K562 and CT26 tumor cells. PHICNQ may trigger apoptosis in tumor cells through inhibition of heat shock protein 70 synthesis and expression.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/biossíntese , Quercetina/análogos & derivados , Quercetina/farmacologia , Western Blotting , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Fatores de Tempo
13.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 24(4): 866-9, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17899762

RESUMO

A DNA fragment encoding human interleukin 4 was obtained by PCR from pORF-hIL4 plasmid. The amplified fragment was inserted into prokaryotic expression vector PQE60 and recombinant protein was expressed in E. Coli M15 by adding isopropyl-beta-D-thiogalactoside (IPTG). The hIL-4 protein was present as insoluble inclusion bodies in the bacterial extract. After denaturation of inclusion bodies with 5 mol/L guanidine hydrochloride, the supernate was diluted to get renaturized. Then dialysis and Ni chelating chromatography were used for purification. TF-1 proliferation assay of recombinant human interleukin 4 was performed, and then rhIL-4 was fit to be used for proliferation of human dendritic cells from monocyte in vitro.


Assuntos
Corpos de Inclusão , Interleucina-4/biossíntese , Proteínas Recombinantes/isolamento & purificação , Escherichia coli/genética , Escherichia coli/metabolismo , Vetores Genéticos , Humanos , Corpos de Inclusão/metabolismo , Interleucina-4/genética , Dobramento de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética
14.
J Mater Sci Mater Med ; 18(3): 449-55, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17334695

RESUMO

Hydrolytic degradable PBT/PEG copolymer was synthesized by macromolecular transesterification method from PBT and PEG macromonomers. The resultant copolymers were characterized by (1)H-NMR and GPC. The non-isothermal crystallization behavior of these copolymers was studied by differential scanning calorimetry (DSC). The water absorption and hydrolytic degradation behavior of PBT/PEG copolymers were also studied in detail.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Poliésteres/química , Poliésteres/síntese química , Polietilenoglicóis/química , Polietilenoglicóis/síntese química , Cristalização , Esterificação , Concentração de Íons de Hidrogênio , Hidrólise , Espectroscopia de Ressonância Magnética , Teste de Materiais , Peso Molecular , Termodinâmica
15.
J Chromatogr A ; 1142(2): 115-22, 2007 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-17222860

RESUMO

In this paper, a rapid separation approach has been developed using high-capacity high-speed counter-current chromatography (high-capacity HSCCC) to isolate and purify honokiol and magnolol, which are the main bioactive constituents from Houpu. The optimization of the solvent selection process, sample loading volume and flow rate is systematically studied using analytical high-capacity HSCCC. The optimized parameters obtained rapidly at analytical scale were used for a 1000 x scale-up preparative run using pilot scale high-capacity HSCCC in a MAXI-DE centrifuge. A crude sample of 43 g was successfully separated and the fractions were analysed by high-performance liquid chromatography (HPLC). This large scale preparative single step run yielded 16.9 and 19.4 g of honokiol and magnolol with purities of 98.6 and 99.9%, in only 20 min. This is the first time that high-performance counter-current chromatography has been used to purify multiple gram grade bioactive compounds in less than 1h and at such high concentrations of final products (10.8 g/l for magnolol and 7.0 g/l for honokiol).


Assuntos
Compostos de Bifenilo/isolamento & purificação , Distribuição Contracorrente/métodos , Lignanas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Projetos Piloto
16.
Gynecol Oncol ; 104(3): 540-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17112567

RESUMO

OBJECTIVE: Vesicular stomatitis virus (VSV) matrix protein (MP) has been reported to be capable of inducing apoptosis in vitro in the absence of other viral components. In the present study, the antitumor effect of a recombinant plasmid encoding VSVMP on human ovarian cancer and its apoptosis-inducing efficacy in vivo were further investigated. METHODS: The recombinant plasmid DNA carrying VSVMP-cDNA (VSVMP-p) was constructed. SKOV3 ovarian cancer cells were transfected with VSVMP-p and examined for apoptosis by Hoechst 33258 staining and flow cytometric analysis. For in vivo study, intraperitoneal ovarian carcinomatosis models in nude mice were established and randomly assigned into four groups to receive six twice-weekly i.p. administrations of VSVMP-p/liposome complexes, empty plasmid/liposome complexes, liposome alone or 0.9% NaCl solution, respectively. The weight of intraperitoneal carcinomatosis and the survival were monitored. Tumor tissues were inspected for apoptosis by TUNEL and Hoechst-33258 assay. RESULTS: Plentiful apoptosis were observed in SKOV3 cells transfected with VSVMP-p. VSVMP-p reduced intraperitoneal tumor weight by about approximately 90% compared with control agents (p<0.01) and significantly prolonged the survival of tumor-bearing mice (p<0.05), with in vivo apoptosis index of 12.6+/-2.7% which was much higher than that of control groups (<4%) (p<0.05). Interestingly, this antitumor effect was accompanied by a noticeable NK cell accumulation. The treatment with VSVMP-p was devoid of any conspicuous toxicity. CONCLUSIONS: These observations suggest that VSVMP-p have strong antitumor effects by inducing apoptosis and possibly NK cell-mediated tumor resistance mechanisms, and it may be a potentially effective novel therapy against human ovarian cancer.


Assuntos
Cistadenocarcinoma Seroso/terapia , Terapia Genética/métodos , Neoplasias Ovarianas/terapia , Vírus da Estomatite Vesicular Indiana/genética , Proteínas da Matriz Viral/genética , Animais , Apoptose/genética , Processos de Crescimento Celular/genética , Linhagem Celular Tumoral , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/imunologia , Cistadenocarcinoma Seroso/patologia , DNA Complementar/administração & dosagem , DNA Complementar/genética , Feminino , Técnicas de Transferência de Genes , Humanos , Linfócitos/imunologia , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Distribuição Aleatória , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Ai Zheng ; 25(8): 941-5, 2006 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16965672

RESUMO

BACKGROUND & OBJECTIVE: Quercetin is a potential chemotherapeutic drug with many biological activities. However, the insolubility of quercetin seriously limits its clinical use. This study was to investigate the biodistribution of quercetin encapsulated by pegylated nanoliposomes and its therapeutic efficacy on the formation of carcinomatous ascites of hepatocellular carcinoma in mice. METHODS: Nanoliposomal quercetin was prepared with conventional rotary evaporation method. BALB/c mice inoculated with hepatocellular carcinoma cells (H22) at the anterior right subaxilla for twelve days were given intravascular injection with nanoliposomal quercetin at 1.5 mg/body (based on quercetin) at different time points. Then the levels of quercetin in the plasma, tumor tissues and normal organs were tested by high pressure liquid chromatography (HPLC). Various dosages of nanoliposomal quercetin were peritoneally given to tumor-bearing mice to determine the optimal dose. The tumor-bearing mice were treated intraperitoneally with 100 mg/kg nanoliposomal quercetin once a day for 14 days. The formation of malignant ascites, increase of body weight, survival time and peritoneal capillary permeability were assessed. Apoptotic cells in ascites were detected by flow cytometry. RESULTS: Nanoliposomal quercetin was a spherical particle with 25% drug content (W/W) and 130+/-20 nm in diameter. Nanoliposomal quercetin effectively aggregated in tumor tissues and its half-life period was 4 h. Nanoliposome quercetin inhibited the formation of malignant ascites of hepatocellular carcinoma model in a dose-dependent manner. Moreover, 100 mg/kg nanoliposomal quercetin significantly enhanced the apoptosis of cancer cells in ascites, inhibited the increase of body weight, reduced peritoneal capillary permeability and prolonged the survival time of tumor-bearing mice compared with PBS control. CONCLUSION: Nanoliposomal quercetin can effectively accumulate in tumor tissues and inhibit the formation of malignant ascites, thus it might be used as a potential antitumor drug which deserves future study.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Ascite/prevenção & controle , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Quercetina/farmacologia , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Ascite/etiologia , Ascite/patologia , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Feminino , Lipossomos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas , Transplante de Neoplasias , Polietilenoglicóis , Quercetina/administração & dosagem , Quercetina/farmacocinética , Distribuição Tecidual
18.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 37(3): 357-60, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16761407

RESUMO

OBJECTIVE: To test the anti-cancer effect of mannan-modified targeted nanoliposome on mice. METHODS: The 3beta[N-(N',N'-dimethylaminoethane) -carbamoyl] cholesterol (DC-chol) was synthesized by the chemical reaction of cholesteryl chloroformate and N, N-dimethylethylendiamine. The DC-chol was then mixed with dioleoylphosphatidylethanolamine (DOPE) and chol-AECM-mannan to produce the sonicated mannan-modified targeted nanoliposome. The size of the nanoliposome was measured by zetasizer. Nanoliposome or purified EGFR (as control) was injected to the C57 mice with implanted lung cancers intravenously. The growth of tumors was observed, followed by ELISA and Western tests of serum antibodies. RESULTS: The liposome nanoparticle had a size of 132 nm. The experimental groups had significant higher levels of blood serum antibodies than the controls. The experimental groups also had less volumes of tumors than the controls (P<0.05). CONCLUSION: The growth of tumor has been inhibited by mannan-modified targeted nanoliposome. The mannan-modified targeted nanoliposome has anti-cancer effect on mice.


Assuntos
Antineoplásicos/administração & dosagem , Colesterol/análogos & derivados , Receptores ErbB/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Mananas/administração & dosagem , Mananas/farmacologia , Animais , Antineoplásicos/farmacologia , Colesterol/administração & dosagem , Colesterol/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Feminino , Lipossomos/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas , Transplante de Neoplasias , Distribuição Aleatória
19.
Clin Cancer Res ; 12(10): 3193-9, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16707620

RESUMO

PURPOSE: Quercetin is a potent chemotherapeutic drug. Clinical trials exploring different schedules of administration of quercetin have been hampered by its extreme water insolubility. To overcome this limitation, this study is aimed to develop liposomal quercetin and investigate its distribution in vivo and antitumor efficacy in vivo and in vitro. EXPERIMENTAL DESIGN: Quercetin was encapsulated in polyethylene glycol 4000 liposomes. Biodistribution of liposomal quercetin i.v. at 50 mg/kg in tumor-bearing mice was detected by high-performance liquid chromatography. Induction of apoptosis by liposomal quercetin in vitro was tested. The antitumor activity of liposomal quercetin was evaluated in the immunocompetent C57BL/6N mice bearing LL/2 Lewis lung cancer and in BALB/c mice bearing CT26 colon adenocarcinoma and H22 hepatoma. Tumor volume and survival time were observed. The mechanisms underlying the antitumor effect of quercetin in vivo was investigated by detecting the microvessel density, apoptosis, and heat shock protein 70 expression in tumor tissues. RESULTS: Liposomal quercetin could be dissolved in i.v. injection and effectively accumulate in tumor tissues. The half-time of liposomal quercetin was 2 hours in plasma. The liposomal quercetin induced apoptosis in vitro and significantly inhibited tumor growth in vivo in a dose-dependent manner. The optimal dose of liposomal quercetin resulted in a 40-day survival rate of 40%. Quantitative real-time PCR showed that liposomal quercetin down-regulated the expression of heat shock protein 70 in tumor tissues. Immunohistochemistry analysis showed that liposomal quercetin inhibited tumor angiogenesis as assessed by CD31 and induced tumor cell apoptosis. CONCLUSIONS: Our data indicated that pegylated liposomal quercetin can significantly improve the solubility and bioavailability of quercetin and can be a potential application in the treatment of tumor.


Assuntos
Adenocarcinoma/tratamento farmacológico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Quercetina/administração & dosagem , Quercetina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Regulação para Baixo , Portadores de Fármacos , Proteínas de Choque Térmico HSP70/biossíntese , Injeções Intravenosas , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Polietilenoglicóis , Quercetina/farmacocinética , Solubilidade , Distribuição Tecidual , Células Tumorais Cultivadas
20.
J Biomed Mater Res A ; 75(2): 465-71, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16094664

RESUMO

In this article, a new kind of biodegradable polyetheresteramide-based polyurethane (PEEA-U) copolymers were prepared by the melt polycondensation method from epsilon-caprolactone, 6-aminocaproic acid, poly(ethylene glycol), and toluene diisocyanate. The water absorption of PEEA-U was affected strongly by the reaction time and the content of chain extender; and the hydrolytic degradation behavior of the copolymers was mainly determined by the reaction time, chain extender content, and the pH value of the degradation medium. Also, DSC, (1)H-NMR, and inherent viscosity were used to characterize the degradation behavior of the copolymers.


Assuntos
Amidas , Materiais Biocompatíveis , Polímeros , Poliuretanos , Implantes Absorvíveis , Amidas/química , Amidas/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Hidrólise , Espectroscopia de Ressonância Magnética , Teste de Materiais , Estrutura Molecular , Polímeros/química , Polímeros/metabolismo , Poliuretanos/química , Poliuretanos/metabolismo , Água/metabolismo
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