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1.
Technol Cancer Res Treat ; 22: 15330338231170495, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37186800

RESUMO

BACKGROUND: The incorporation of noncoplanar beam arrangements has been proposed in liver radiotherapy modalities, which can reduce the dose in normal tissues compared to coplanar techniques. Noncoplanar radiotherapy techniques for hepatocellular carcinoma treatment based on the Linac design have a limited effective arc angle to avoid collisions. PURPOSE: To propose a novel noncoplanar volumetric modulated arc therapy technique based on a cage-like radiotherapy system and investigate its performance in hepatocellular carcinoma patients. METHODS: The computed tomography was deflected 90° to meet the structure of a cage-like radiotherapy system and design the noncoplanar volumetric modulated arc therapy technique based on a cage-like radiotherapy system plan in the Pinnacle3 planning system. An noncoplanar volumetric modulated arc therapy technique based on a cage-like radiotherapy system plan was customized for each of 10 included hepatocellular carcinoma patients, with 6 dual arcs ranging from -30° to 30°. Six couch angles were set with an interval of 36° and distributed along with the longest diameter of planning target volume. The dosimetric parameters of noncoplanar volumetric modulated arc therapy technique based on a cage-like radiotherapy system plan were compared with the noncoplanar volumetric modulated arc therapy and volumetric modulated arc therapy plan. RESULTS: The 3 radiotherapy techniques regarding planning target volume were statistically different for D98%, D2%, conformity index, and homogeneity index with χ2 = 9.692, 14.600, 8.600, and 12.600, and P = .008, .001, .014, and .002, respectively. Further multiple comparisons revealed that noncoplanar volumetric modulated arc therapy technique based on a cage-like radiotherapy system significantly reduced the mean dose (P = .005) and V5 (P = .005) of the normal liver, the mean dose (P = .005) of the stomach, and V30 (P = .028) of the lung compared to noncoplanar volumetric modulated arc therapy. Noncoplanar volumetric modulated arc therapy technique based on a cage-like radiotherapy system significantly reduced the mean dose (P = .005) and V5 (P = .005) of the normal liver, the mean dose (P = .017) of the spinal cord, V50 (P = .043) of the duodenum, the maximum dose (P = .007) of the esophagus, and V30 (P = .047) of the whole lung compared to volumetric modulated arc therapy. The results indicate that noncoplanar volumetric modulated arc therapy technique based on a cage-like radiotherapy system protects the normal liver, stomach, and lung better than noncoplanar volumetric modulated arc therapy and protects the normal liver, spinal cord, duodenum, esophagus, and lung better than volumetric modulated arc therapy. CONCLUSIONS: The noncoplanar volumetric modulated arc therapy technique based on a cage-like radiotherapy system technique with the arrangement of noncoplanar arcs provided optimal dosimetric gains compared with noncoplanar volumetric modulated arc therapy and volumetric modulated arc therapy, except for the heart. Noncoplanar volumetric modulated arc therapy technique based on a cage-like radiotherapy system should be considered in more clinically challenging cases.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Radioterapia de Intensidade Modulada/métodos , Carcinoma Hepatocelular/radioterapia , Dosagem Radioterapêutica , Órgãos em Risco , Planejamento da Radioterapia Assistida por Computador/métodos , Radiocirurgia/métodos , Neoplasias Hepáticas/radioterapia
2.
Heliyon ; 9(3): e14171, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36938470

RESUMO

Aim: Diabetic nephropathy (DN) is the primary cause of end-stage renal disease worldwide. Although etiology for DN is complex and still needs to be fully understood, lipid metabolism disorder is found to play a role in it. Previously, we found Yishen Huashi (YSHS) granule could inhibit diabetic damage and reduce level of microalbuminuria (mALB) in DN animals. To explore its role and mechanism in lipid metabolism under DN settings, this study was designed. Materials and methods: DN rats were induced by streptozotocin (STZ), HepG2 and CaCO2 cells were applied for in vitro study. Hematoxylin-Eosin (HE), periodic acid-Schiff (PAS) staining, and Transmission Electron Microscopy (TEM) were applied for histological observation; 16s Sequencing was used for intestinal microbiota composition analysis; western blotting (WB) and immunofluorescence were carried out for molecular biological study, and enzyme-linked immunosorbent assay (ELISA) was used for lipid determination. Results: YSHS administration significantly reduced levels of total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL-C), while increased level of high-density lipoprotein (HDL-C); meanwhile, histological changes and steatosis of the liver was ameliorated, integrity of the intestinal barrier was enhanced, and dysbacteriosis within intestinal lumen was ameliorated. Mechanism study found that YSHS modulated mitophagy within hepatocytes and inhibited mTOR/AMPK/PI3K/AKT signaling pathway. Conclusion: In conclusion, we found in the present study that YSHS administration could ameliorate lipid metabolism disorder in DN animals, and its modulation on intestinal-liver axis played a significant role in it.

3.
Front Oncol ; 13: 1041769, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36925918

RESUMO

Purpose: Deep-learning effectively predicts dose distributions in knowledge-based radiotherapy planning. Using anatomical information that includes a structure map and computed tomography (CT) data as input has been proven to work well. The minimum distance from each voxel in normal structures to planning target volume (DPTV) closely affects each voxel's dose. In this study, we combined DPTV and anatomical information as input for a deep-learning-based dose-prediction network to improve performance. Materials and methods: One hundred patients who underwent volumetric-modulated arc therapy for nasopharyngeal cancer were selected in this study. The prediction model based on a residual network had DPTV maps, structure maps, and CT as inputs and the corresponding dose distribution maps as outputs. The performances of the combined distance and anatomical information (COM) model and the traditional anatomical (ANAT) model with two-channel inputs (structure maps and CT) were compared. A 10-fold cross validation was performed to separately train and test the COM and ANAT models. The voxel-based mean error (ME), mean absolute error (MAE), dosimetric parameters, and dice similarity coefficient (DSC) of isodose volumes were used for modeling evaluation. Results: The mean MAE of the body volume of the COM model were 4.89 ± 1.35%, highly significantly lower than those for the ANAT model of 5.07 ± 1.37% (p<0.001). The ME values of the body for the 2-type models were similar (p >0.05). The mean DSC values of the isodose volumes in the range of 60 Gy were all better in the COM model (p<0.05), and there were highly significant differences between 10 Gy and 55 Gy (p<0.001). For most organs at risk, the ME, MAE, and dosimetric parameters predicted by both models were concurrent with the ground truth values except the MAE values of the pituitary and optic chiasm in the ANAT model and the average mean dose of the right parotid in the ANAT model. Conclusions: The COM model outperformed the ANAT model and could improve automated planning with statistically highly significant differences.

4.
Curr Mol Pharmacol ; 16(7): 751-758, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36200156

RESUMO

BACKGROUNDS: Hypertensive nephropathy (HN) is a kind of renal disease caused by essential hypertension that eventually worsens into end-stage renal disease (ESRD). HN could damage the renal tubules, induce kidney damage and renal failure, and increase the risk of stroke, heart disease or death, but there are few ideal drugs for HN treatment. METHODS: In this study, we explored the therapeutic effect of bajijiasu (a compound from Morinda officinalis how and a common traditional Chinese medicine for tonifying the kidney) on the HN rat model. Biochemical analysis, HE staining, and PAS staining were used to assess the effects of bajijiasu on HN rat model. Western blotting was used to analyze the potential mechanisms. RESULTS: The results of HE staining and PAS staining showed that bajijiasu could alleviate the pathological changes in HN rat models; biochemical analysis found that the concentration of Malondialdehyde (MDA), total protein (TP), albumin (ALB), microalbuminuria (MALB), blood urea nitrogen (BUN), creatinine (Cr), triglyceride (TG), and low-density lipoprotein-cholesterol (LDL-C) were significantly decreased compared with the model group after bajijiasu treatment; and bajijiasu could regulate the expression of TNF-α, IL-6, MDA, SOD1 and AGEs in HN rats; the result of western blotting demonstrated that bajijiasu could down-regulate the expression of TGFß1, NOX4, JNK, p- JNK and up-regulate the expression PPARγ and SOD 1 in HN rats. CONCLUSION: Those results demonstrated that bajijiasu could alleviate the pathological changes and physiological and biochemical symptoms of HN rat models by regulating the expression of TGFß1, PPARγ, JNK, p-JNK, NOX4 and SOD1 but could not lower the blood pressure of HN rats. Those pieces of evidence may provide a new therapeutic method for HN treatment.


Assuntos
Hipertensão Renal , PPAR gama , Ratos , Animais , Superóxido Dismutase-1 , Rim/patologia , Hipertensão Renal/tratamento farmacológico , Hipertensão Renal/patologia
5.
Front Pharmacol ; 13: 872940, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935814

RESUMO

Background: Diabetic nephropathy (DN) is one of the most common complications of diabetes and the primary cause of end-stage renal disease. At present, renin-angiotensin-aldosterone system (RAAS) blockers have been applied as first-class drugs to restrain development of DN; however, its long-term effect is limited. Recent evidence has shown definite effects of Chinese medicine on DN. Yishen Huashi (YSHS) granule is a traditional Chinese Medicine prescription that has been used in the clinic to treat DN, but its mechanism is not understood. Methods: In the present study, both in vitro and in vivo studies were carried out. The DN model was induced by STZ in Wistar rats, and GEnC and HPC cell lines were applied in the in vitro study. Quality of YSHS was evaluated by LC-MS/MS. A metabolomic study of urine was carried out by LC-MS; influence of YSHS on composition of DN was analyzed by network pharmacology. Mechanism of the YSHS on DN was analyzed by Q-PCR, Western Blot, and multi-immunological methods. Results: We found YSHS administration significantly reduced levels of HbA1c and mALB. Histopathological analysis found that YSHS preserved integrity of glomerular filtration barrier by preserving viability of glomerular endothelial cells and podocytes, inhibiting glomerular fibrosis, reducing oxidative stress damage, and enhancing cross-talk among glomerular endothelial cells and podocytes. Network pharmacology, differential metabolite analysis, as well as intracellular pathway experimental study demonstrated that the PI3K/AKT/mTOR signaling pathway played a pivotal role in it. Conclusion: Our present findings supplied new understanding toward the mechanism of YSHS on inhibiting DN.

6.
Phys Med Biol ; 66(22)2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34700300

RESUMO

Objective:Megavoltage computed tomography (MV-CT) is used for setup verification and adaptive radiotherapy in tomotherapy. However, its low contrast and high noise lead to poor image quality. This study aimed to develop a deep-learning-based method to generate synthetic kilovoltage CT (skV-CT) and then evaluate its ability to improve image quality and tumor segmentation.Approach:The planning kV-CT and MV-CT images of 270 patients with nasopharyngeal carcinoma (NPC) treated on an Accuray TomoHD system were used. An improved cycle-consistent adversarial network which used residual blocks as its generator was adopted to learn the mapping between MV-CT and kV-CT and then generate skV-CT from MV-CT. A Catphan 700 phantom and 30 patients with NPC were used to evaluate image quality. The quantitative indices included contrast-to-noise ratio (CNR), uniformity and signal-to-noise ratio (SNR) for the phantom and the structural similarity index measure (SSIM), mean absolute error (MAE), and peak signal-to-noise ratio (PSNR) for patients. Next, we trained three models for segmentation of the clinical target volume (CTV): MV-CT, skV-CT, and MV-CT combined with skV-CT. The segmentation accuracy was compared with indices of the dice similarity coefficient (DSC) and mean distance agreement (MDA).Mainresults:Compared with MV-CT, skV-CT showed significant improvement in CNR (184.0%), image uniformity (34.7%), and SNR (199.0%) in the phantom study and improved SSIM (1.7%), MAE (24.7%), and PSNR (7.5%) in the patient study. For CTV segmentation with only MV-CT, only skV-CT, and MV-CT combined with skV-CT, the DSCs were 0.75 ± 0.04, 0.78 ± 0.04, and 0.79 ± 0.03, respectively, and the MDAs (in mm) were 3.69 ± 0.81, 3.14 ± 0.80, and 2.90 ± 0.62, respectively.Significance:The proposed method improved the image quality of MV-CT and thus tumor segmentation in helical tomotherapy. The method potentially can benefit adaptive radiotherapy.


Assuntos
Aprendizado Profundo , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Humanos , Processamento de Imagem Assistida por Computador/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/radioterapia , Tomografia Computadorizada por Raios X
7.
J Appl Clin Med Phys ; 22(5): 15-23, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33829650

RESUMO

BACKGROUND: Hippocampal-avoidance prophylactic cranial irradiation (HA-PCI) offers potential neurocognitive benefits but raises technical challenges to treatment planning. This study aims to improve the conventional planning method using volumetric modulated arc therapy (VMAT) technique and investigate a better patient's head positioning to achieve a high quality of HA-PCI treatment plans. METHODS: The improved planning method set a wide expansion of hippocampus as a special region for dose decline. The whole brain target was divided into two parts according to whether the slice included hippocampus and their optimization objectives were set separately. Four coplanar full arcs with partial field sizes were employed to deliver radiation dose to different parts of the target. The collimator angle for all arcs was 90°. Tilting patient's head was achieved by rotating CT images. The improved planning method and tilted head positioning were verified using datasets from 16 patients previously treated with HA-PCI using helical tomotherapy (HT). RESULTS: For the improved VMAT plans, the max and mean doses to hippocampus were 7.88 Gy and 6.32 Gy, respectively, significantly lower than those for the conventional VMAT plans (P < 0.001). Meanwhile, the improved planning method significantly improved the plan quality. Compared to the HT plans, the improved VMAT plans result in similar mean dose to hippocampus (P > 0.1) but lower max dose (P < 0.02). Besides, the target coverage was the highest for the improved VMAT plans. The tilted head positioning further reduced the max and mean doses to hippocampus (P < 0.05), significantly decreased the max dose to lens (P < 0.001) and resulted in higher plan quality as compared to nontilted head positioning. CONCLUSIONS: The improved planning method enables the VMAT plans to meet the clinical requirements of HA-PCI treatment with high plan quality and convenience. The tilted head positioning provides superior dosimetric advantages over the nontilted head positioning, which is recommended for clinical application.


Assuntos
Intervenção Coronária Percutânea , Radioterapia de Intensidade Modulada , Irradiação Craniana , Hipocampo , Humanos , Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
8.
Front Oncol ; 10: 571644, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33344231

RESUMO

PURPOSE: The aim of this work is to introduce the 2019 International Planning Competition and to analyze its results. METHODS AND MATERIALS: A locally advanced non-small cell lung cancer (LA-NSCLC) case using the simultaneous integrated boost approach was selected. The plan quality was evaluated by using a ranking system in accordance with practice guidelines. Planners used their clinical Treatment Planning System (TPS) to generate the best possible plan along with a survey, designed to obtain medical physics aspects information. We investigated the quality of the large population of plans designed by worldwide planners using different planning and delivery systems. The correlations of plan quality with relevant planner characteristics (work experience, department scale, and competition experience) and with technological parameters (TPS and modality) were examined. RESULTS: The number of the qualified plans was 287 with a wide range of scores (38.61-97.99). The scores showed statistically significant differences by the following factors: 1) department scale: the mean score (89.76 ± 8.36) for planners from the departments treating >2,000 patients annually was the highest of all; 2) competition experience: the mean score for the 107 planners with previous competition experience was 88.92 ± 9.59, statistically significantly from first-time participants (p = .001); 3) techniques: the mean scores for planners using VMAT (89.18 ± 6.43) and TOMO (90.62 ± 7.60) were higher than those using IMRT (82.28 ± 12.47), with statistical differences (p <.001). The plan scores were negligibly correlated with the planner's years of work experience or the type of TPS used. Regression analysis demonstrated that plan score was associated with dosimetric objectives that were difficult to achieve, which is generally consistent with a clinical practice evaluation. However, 51.2% of the planners abandoned the difficult component of total lung receiving a dose of 5 Gy in their plan design to achieve the optimal plan. CONCLUSION: The 2019 international planning competition was carried out successfully, and its results were analyzed. Plan quality was not correlated with work experiences or the TPS used, but it was correlated with department scale, modality, and competition experience. These findings differed from those reported in previous studies.

9.
Clin Exp Pharmacol Physiol ; 47(8): 1382-1392, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32155673

RESUMO

In this study, we investigated the lipid metabolism regulatory activity of a novel metformin derivative (MD568) and its potential mechanism of action in obese rats with type 2 diabetes mellitus (T2 DM). Previous gene chip analysis of 3T3-L1 cells have shown that MD568 regulates the transcription of genes involved in the peroxisome proliferator-activated receptor (PPAR) signalling pathway, fatty acid metabolism, and glycerolipid metabolism. In this study, obese T2 DM rats were treated with MD568 (200 mg/kg) for 8 weeks. Results showed that MD568 significantly reduced the body weight gain, plasma glucose, insulin, total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels. MD568 treatment also improved the insulin resistance of obese T2 DM model rats. In particular, in white adipose tissue, MD568 inhibited the excessive volume increment of adipose cells by down-regulating the protein levels of CCAAT/enhancer-binding protein-α (C/EBP-α) and PPAR-γ, as well as the transcription of their target lipid metabolism-related genes. In the liver, MD568 inhibited hepatic fatty lesions and interfered with hepatic gluconeogenesis by regulating the expression of lipid metabolism-related genes and glycogen-related kinases. In conclusion, our results suggest that the newly synthesized MD568 affects the maintenance of lipid homeostasis in obese type 2 diabetic rats.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metformina/química , Metformina/farmacologia , Obesidade/complicações , Animais , Masculino , Ratos
10.
Chem Biodivers ; 17(4): e1900684, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32064755

RESUMO

Anemarrhena asphodeloides Bunge is a traditional Chinese medicine. The timosaponin BII is one of the most abundant and widely studied active ingredients in Anemarrhena asphodeloides Bunge. Related studies have shown that timosaponin BII has potential value for development and further utilization. The protective effect of timosaponin BII on islet ß cells under type 2 diabetes was investigated in the glycolipid toxic INS-1 cell model and possible biomarkers were explored by lipidomics analysis. Timosaponin BII was isolated from Anemarrhena asphodeloides Bunge by polyamide resin and Sephadex LH-20. Then, the glycolipid toxicity INS-1 cell model was established to investigate the protective effect of timosaponin BII. The results showed that timosaponin BII could significantly influence the levels of malondialdehyde (MDA) and glutathione (GSH), thereby restoring the insulin secretion ability and cell viability of model cells. Lipidomics analysis was combined with multivariate statistical analysis for marker selection. The four most common pathological and pharmacological lipid markers were phosphatidylserine (PS), suggesting that timosaponin BII had protective effects on model cells related to the reduction oxidative stress and macrophage inflammation. RAW264.7 macrophages were stimulated by LPS to establish a model of inflammation and study the effect of timosaponin BII on the nodes of NOD-like receptor P3 (NLRP3) inflammasome pathway in the model cells. In conclusion, timosaponin BII may have the effect of protecting INS-1 pancreatic ß cells through reducing IL-1ß (interleukin-1ß) production by inhibiting the NLRP3 inflammasome in macrophage and restoring the insulin secretion ability and cell viability by reducing oxidative stress.


Assuntos
Anemarrhena/química , Glicolipídeos/toxicidade , Substâncias Protetoras/química , Saponinas/química , Esteroides/química , Anemarrhena/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Análise Discriminante , Glutationa/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Inflamação/prevenção & controle , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Interleucina-1beta/metabolismo , Lipidômica/métodos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Malondialdeído/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Análise de Componente Principal , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Células RAW 264.7 , Saponinas/isolamento & purificação , Saponinas/farmacologia , Saponinas/uso terapêutico , Esteroides/isolamento & purificação , Esteroides/farmacologia , Esteroides/uso terapêutico
11.
Sensors (Basel) ; 19(10)2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31096714

RESUMO

: Urban road intersections play an important role in deciding the total travel time and the overall travel efficiency. In this paper, an innovative traffic grid model has been proposed, which evaluates and diagnoses the traffic status and the time delay at intersections across whole urban road networks. This method is grounded on a massive amount of floating car data sampled at a rate of 3 s, and it is composed of three major parts. (1) A grid model is built to transform intersections into discrete cells, and the floating car data are matched to the grids through a simple assignment process. (2) Based on the grid model, a set of key traffic parameters (e.g., the total time delay of all the directions of the intersection and the average speed of each direction) is derived. (3) Using these parameters, intersections are evaluated and the ones with the longest traffic delays are identified. The obtained intersections are further examined in terms of the traffic flow ratio and the green time ratio as well as the difference between these two variables. Using the central area of Beijing as the case study, the potential and feasibility of the proposed method are demonstrated and the unreasonable signal timing phases are detected. The developed method can be easily transferred to other cities, making it a useful and practical tool for traffic managers to evaluate and diagnose urban signal intersections as well as to design optimal measures for reducing traffic delay and increase operation efficiency at the intersections.

12.
Phys Chem Chem Phys ; 20(15): 10038-10047, 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-29620132

RESUMO

Gadolinium oxide-based core-shelled nanoparticles have recently emerged as novel magnetic resonance imaging contrast agents for high relaxivity and tumor targeting. However, their relaxivity enhancement mechanism has not yet been clearly understood. We prepared highly dispersible and uniform core-shell structured nanoparticles by encapsulating silica spheres (90 nm in diameter) with gadolinium oxide shells of different thicknesses (from 1.5 nm to 20 nm), and proved experimentally that the shell thickness has an inverse effect on relaxivity. The core-shelled nanoparticles are of a larger relaxivity than the commercial contrast agent Gd-DTPA, with an enhancement from 1.8 to 7.3 times. Based on the Solomon-Bloembergen-Morgan theory which is usually adopted for interpreting the relaxation changes of water protons in Gd3+ chelates, we introduced a shielding ansatz of nanoshells and derived a concise formula specifically to correlate the relaxivity of this sort of core-shelled nanoparticles with the shell thickness directly. The formula calculation is well consistent with the experimental results, and the formula can be generally applied to evaluate the relaxation enhancement underlying the high relaxivity of any core-shelled nanoparticle. Furthermore, the core-shelled nanoparticles possess a negligible nanotoxicity according to the in vitro cytotoxicity and in vivo histopathology and hematology assays. The enhanced signals of in vivo tumor-targeted magnetic resonance imaging indicate that the ultrathin gadolinium oxide nanoshells may function as a potential candidate for advanced positive contrast agents in further clinical applications.

13.
Nanoscale ; 9(43): 16661-16673, 2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-28809413

RESUMO

Multifunctional nanoprobes, due to their unique nanocomposite structures, have prominent advantages that combine multimodal imaging of a tumor with photothermal therapy. However, they remain a challenge for constructing nanostructures via conventional approaches due to the peculiar environmental sensitivity of each component. Here, we report the design and synthesis of Gd-based nanoparticle-tailored gold nanorods with distinctive core-shell and dumbbell nanoarchitectures (NAs) by a specific synthesis technology. The prepared NAs possess a tunable particle size of 80-120 nm in length and 50-90 nm in diameter, which are suitable for cellular uptake and passive targeting of a tumor. The formation of two distinct heterostructures and their underlying mechanism were studied through systematic investigations on the controllable synthesis process. The as-prepared nanoprobes possess an ultrahigh longitudinal relaxivity (r1) of 22.69 s-1 mM-1 and thus a significant magnetic resonance imaging signal enhancement has been observed in mice tumors. The NAs, especially the dumbbell type, show a vivid two-photon cell imaging and a remarkable photothermal conversion efficiency owing to their superior longitudinal surface plasmon resonance. Both in vitro cytotoxicity and in vivo immunotoxicity assays give substantial evidence of excellent biocompatibility attained in the NAs. The development of multifunctional targeting nanoprobes in this study could provide guidance for tailored design and controllable synthesis of heterostructured nanocomposites utilized for multimodal imaging and photothermal therapy of cancer.

14.
Phys Chem Chem Phys ; 19(7): 5366-5376, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28155924

RESUMO

We report a class of multi-functional core-shell nanoarchitectures, consisting of silica nanospheres as the core and Gd2O3:Dy3+ nanocrystals as the ultra-thin shell, that enable unique multi-color living cell imaging and remarkable in vivo magnetic resonance imaging. These types of targeted cell imaging nanoarchitectures can be used as a variety of fluorescence nanoprobes due to the multi-color emissions of the Gd2O3:Dy3+ nanophosphor. We also proposed a strategy of modulating core-shell structure design to achieve an enhanced magnetic resonance contrast ability of Gd2O3 nanoagents, and the classical Solomon-Bloembergen-Morgan theory was applied to explicate the mechanism underlying the enhancement. The as-synthesized ligand-free nanomaterial possesses a suitable particle size for cellular uptake as well as avoiding penetrating the blood-brain barrier with good water-solubility, stability, dispersibility and uniformity. The extremely low cytotoxicity and favorable biocompatibility obtained from in vitro and in vivo bioassays of the as-designed nanoparticles indicate their excellent potential as a candidate for functioning as a targeted nanoprobe.


Assuntos
Disprósio/química , Corantes Fluorescentes/química , Corantes Fluorescentes/toxicidade , Gadolínio/química , Imageamento por Ressonância Magnética , Nanopartículas/química , Imagem Óptica , Animais , Sobrevivência Celular/efeitos dos fármacos , Gadolínio/toxicidade , Células HEK293 , Células HeLa , Humanos , Camundongos , Nanopartículas/toxicidade
15.
Water Sci Technol ; 70(7): 1285-91, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25325555

RESUMO

Aimed at cost saving and pollution reduction, a novel desulfurization wastewater evaporation treatment system (DWETS) for handling wet flue gas desulfurization (WFGD) wastewater of a coal-fired power plant was studied. The system's advantages include simple process, and less investment and space. The feasibility of this system has been proven and the appropriate position and number of nozzles, the spray droplet size and flue gas temperature limitation have been obtained by computational fluid dynamics (CFD) simulation. The simulation results show that a longer duct, smaller diameter and higher flue gas temperature could help to increase the evaporation rate. The optimal DWETS design of Shangdu plant is 100 µm droplet sprayed by two nozzles located at the long duct when the flue gas temperature is 130 °C. Field tests were carried out based on the simulation results. The effects of running DWETS on the downstream devices have been studied. The results show that DWETS has a positive impact on ash removal efficiency and does not have any negative impact on the electrostatic precipitator (ESP), flue gas heat exchanger and WFGD. The pH values of the slurry of WFGD slightly increase when the DWETS is running. The simulation and field test of the DWETS show that it is a feasible future technology for desulfurization wastewater treatment.

17.
Curr Opin Drug Discov Devel ; 5(3): 414-21, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12058617

RESUMO

With the influx of targets generated by genomics and proteomics initiatives, a new drug discovery paradigm is emerging. Many companies are setting up target family platforms that tackle multiple targets and therapeutic areas simultaneously. Virtual screening (VS) techniques are a fundamental component of such platforms for in silico filtering of compound collections and prioritization of chemistry and screening efforts. At the heart of these, structure-based docking and scoring methods are especially effective in identifying bioactive molecules if the structure of a target is available. As structural genomics maps the structural space of the proteome, these techniques are expected to become commonplace. In light of this, an overview of the latest developments in VS methodology is given here. In particular, emphasis is placed on those techniques adaptable to high-throughput VS in parallel drug discovery platforms. The first examples of docking across multiple targets have already appeared in the literature and will be reviewed here.


Assuntos
Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Animais , Sítios de Ligação/efeitos dos fármacos , Técnicas de Química Combinatória/métodos , Técnicas de Química Combinatória/tendências , Humanos , Relação Estrutura-Atividade
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