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1.
ACS Appl Mater Interfaces ; 13(33): 39957-39966, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34376049

RESUMO

Microbial inoculants can enhance soil quality, promote plant nutrient acquisition, and alleviate problems caused by the excessive use of chemical fertilizers. However, susceptibility to harsh conditions during transport and storage, as well as the short shelf-life of plant growth-promoting rhizobacteria (PGPR), limit industrial application. Herein, a novel strategy to form nanocoating on bacterial surfaces to enhance viability was proposed. The nanocoating was composed of N-hydroxysuccinimide (NHS)-modified poly (γ-glutamic acid) (γ-PGA) and calcium ions, which could adhere to the surface of bacteria by forming covalent bonds and ionic bonds with the bacteria. The bacteria encapsulated in the coating had better resistance against harsh conditions than bare bacteria. The viability of coated bacteria was also increased by 2.38 times compared with bare bacteria after 4 weeks of storage. The pot experiment showed that coated Pseudomonas stutzeri NRCB010 had better growth-promoting properties compared with free P. stutzeri NRCB010. These results indicate that cell surface engineering is an effective method to enhance the resistance of bacteria against harsh conditions and is expected to promote the widespread use of PGPR.


Assuntos
Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/metabolismo , Nanoestruturas/química , Ácido Poliglutâmico/análogos & derivados , Pseudomonas stutzeri/metabolismo , Biotecnologia , Proliferação de Células/efeitos dos fármacos , Fertilizantes/microbiologia , Temperatura Alta , Engenharia Metabólica , Viabilidade Microbiana/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Ácido Poliglutâmico/química , Ácido Poliglutâmico/metabolismo , Pseudomonas stutzeri/efeitos dos fármacos , Exposição à Radiação , Solo , Estresse Mecânico
2.
Biomater Sci ; 9(17): 5977-5987, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34338256

RESUMO

Nanodrug delivery systems have been used extensively to improve the tumor-targeting ability and reduce the side effects of anticancer drugs. In this study, nanomicelles responsive to dual stimuli were designed and developed as drug carriers for delivering doxorubicin (DOX). The hydrophobic group of the nanomicelles was composed of the photosensitizer protoporphyrin IX (PpIX) and the disulfide bond-containing alpha-lipoic acid (LA); the hydrophilic group was made up of the nuclear localization signal (NLS, CGGGPKKKRKVGG) peptide with a lysine linker. Furthermore, anionic cyclo-γ-polyglutamic acid (cyclo-γ-PGA) was coated on the surface of the cationic micelles to construct a multifunctional drug delivery system (NLS-LA-PpIX-DOX@cyclo-γ-PGA). Cyclo-γ-PGA, as a biological coating material, notably improved the stability of the cationic micelles by reducing nonspecific reactions with anionic groups. Additionally, the cyclo-γ-PGA coating mediated active tumor targeting and enhanced the cellular uptake of micelles via the γ-glutamyl transpeptidase (GGT) pathway. The integrated micelles not only achieved photochemical internalization (PCI) and photodynamic therapy (PDT) via light-activated reactive oxygen species (ROS) but also realized controlled intracellular drug release via the glutathione (GSH)-responsive disulfide-bond cleavage. As a result, NLS-LA-PpIX-DOX@cyclo-γ-PGA exhibited excellent synergistic chemo-photodynamic antitumor activity and fewer side effects than other therapies both in vitro and in vivo. In conclusion, this new dual-responsive drug delivery system (NLS-LA-PpIX-DOX@cyclo-γ-PGA) with improved stability and enhanced tumor-targeting ability may facilitate the development of high-efficiency and low-toxicity nanotherapeutic approaches.


Assuntos
Fotoquimioterapia , Ácido Poliglutâmico , Doxorrubicina/farmacologia , Portadores de Fármacos , Liberação Controlada de Fármacos , Micelas , Ácido Poliglutâmico/análogos & derivados
3.
Int J Nanomedicine ; 16: 4239-4250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194227

RESUMO

Purpose: Pore-forming toxins (PFTs) perform important functions during bacterial infections. Among various virulence-targeting therapies, nanosponges (NSs) have excellent neutralization effects on multiple PFTs. To enhance treatment efficacy, NSs tend to be incorporated into other biomaterials, such as hydrogels. Methods: In the present work, red blood cell (RBC) vesicles were harvested to wrap polymer nanoparticles, leading to the formation of NSs, and the optimal Pluronic F127 hydrogel concentration was determined for gelation. Then, a novel detoxification system was constructed by incorporating NSs into an optimized Pluronic F127 hydrogel (NS-pGel). Next, the system was characterized by rheological and sustained release behavior as well as micromorphology. Then, the in vitro neutralization effect of NS-pGel on various PFTs was examined by a hemolysis protocol. Finally, therapeutic and prophylactic detoxification efficiency was evaluated in a mouse subcutaneous infection model in vivo. Results: A thermosensitive, injectable detoxification system was successfully constructed by loading NSs into a 30% Pluronic F127 hydrogel. Characterization results demonstrated that the NS-pGel hybrid system sustained an ideal fluidity and viscosity at lower temperatures but exhibited a quick sol-gel transition capacity near body temperature. In addition, this hybrid system had a sustained release behavior accompanied by good biocompatibility and biodegradability. Finally, the NS-pGel system showed neutralization effects similar to those of NSs both in vitro and in vivo, indicating a good preservation of NS functionality. Conclusion: In conclusion, we constructed a novel temperature-sensitive detoxification system with good biocompatibility and biodegradability, which may be applied to the clinical treatment of PFT-induced local lesions and infections.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/química , Hidrogéis/administração & dosagem , Hidrogéis/química , Poloxâmero/química , Animais , Proteínas de Bactérias , Materiais Biocompatíveis , Eritrócitos/química , Proteínas Hemolisinas , Hemólise/efeitos dos fármacos , Masculino , Teste de Materiais , Camundongos Endogâmicos ICR , Nanopartículas/química , Testes de Neutralização , Reologia , Staphylococcus aureus/patogenicidade , Temperatura , Vibrio vulnificus/patogenicidade , Viscosidade
4.
Toxicon ; 187: 35-46, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32871160

RESUMO

We characterized and compared the venom protein profiles of Hydrophis curtus (synonyms: Lapemis hardwickii, Lapemis curtus and Hydrophis hardwickii) and Hydrophis cyanocinctus, the two representatives of medically important venomous sea snakes in Chinese waters using proteomic approaches. A total of 47 and 38 putative toxins were identified in H. curtus venom (HcuV) and H. cyanocinctus venom (HcyV), respectively, and these toxins could be grouped into 15 functional categories, mainly proteinases, phospholipases, three-finger toxins (3FTxs), lectins, protease inhibitors, ion channel inhibitors, cysteine-rich venom proteins (CRVPs) and snake venom metalloproteases (SVMPs). The constituent ratio of each toxin category varied between HcuV and HcyV with 3FTx (54% in HcuV/69% in HcyV) and PLA2 (38% in HcuV/22% in HcyV) unanimously ranked as the top two most abundant families. Both HcuV and HcyV exhibited relatively high lethality (LD50 values in mice of 0.34 µg/g and 0.24 µg/g, respectively), specific PLA2 activity and hemolytic activity. On the basis of several previous reports of HcuV and HcyV collected from other areas, these findings greatly expand our understanding of geographical variation and interspecies diversity of the two sea snake venoms and can provide a scientific basis for the development of specific sea snake antivenom in the future.


Assuntos
Venenos Elapídicos , Hydrophiidae , Proteoma/metabolismo , Animais , Toxinas Biológicas
5.
J Med Internet Res ; 22(8): e20108, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32716901

RESUMO

BACKGROUND: The number of deaths worldwide caused by coronavirus disease (COVID-19) is increasing rapidly. Information about the clinical characteristics of patients with COVID-19 who were not admitted to hospital is limited. Some risk factors of mortality associated with COVID-19 are controversial (eg, smoking). Moreover, the impact of city closure on mortality and admission rates is unknown. OBJECTIVE: The aim of this study was to explore the risk factors of mortality associated with COVID-19 infection among a sample of patients in Wuhan whose conditions were reported on social media. METHODS: We enrolled 599 patients with COVID-19 from 67 hospitals in Wuhan in the study; 117 of the participants (19.5%) were not admitted to hospital. The demographic, epidemiological, clinical, and radiological features of the patients were extracted from their social media posts and coded. Telephone follow-up was conducted 1 month later (between March 15 and 23, 2020) to check the clinical outcomes of the patients and acquire other relevant information. RESULTS: The median age of patients with COVID-19 who died (72 years, IQR 66.5-82.0) was significantly higher than that of patients who recovered (61 years, IQR 53-69, P<.001). We found that lack of admission to hospital (odds ratio [OR] 5.82, 95% CI 3.36-10.1; P<.001), older age (OR 1.08, 95% CI 1.06-1.1; P<.001), diffuse distribution (OR 11.09, 95% CI 0.93-132.9; P=.058), and hypoxemia (odds ratio 2.94, 95% CI 1.32-6.6; P=.009) were associated with increasing odds of death. Smoking was not significantly associated with mortality risk (OR 0.9, 95% CI 0.44-1.85; P=.78). CONCLUSIONS: Older age, diffuse distribution, and hypoxemia are factors that can help clinicians identify patients with COVID-19 who have poor prognosis. Our study suggests that aggregated data from social media can also be comprehensive, immediate, and informative in disease prognosis.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Criança , Pré-Escolar , China , Feminino , Hospitalização , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prognóstico , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Mídias Sociais , Adulto Jovem
6.
PLoS One ; 15(2): e0229559, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32109942

RESUMO

Gap-graded soils from mountain areas are often used as subgrade filling materials, but problems associated with the gap-graded soils such as large permeability, poor uniformity, and poor seepage stability have to be solved. This article proposes a new terminology "void filling ratio" to study the seepage internal stability of gap-graded soils as subgrade filling materials. Laboratory seepage tests were performed to investigate the effects of compaction degrees of coarse grains, void filling ratios, and clay contents on the internal stability. Laboratory model tests were also performed to verify the findings from the laboratory seepage tests. It was found that the internal stability increased with increase of the void filling ratios, confirmed by both laboratory seepage tests and slope model tests. The increases of both void filling ratio and the clay content were able to change the type of internal instability from piping to the transitional type of internal instability. In laboratory model tests, surface areas lost more fine particles than the deeper area did in the models, but when the void filling ratio was increased, the amount of lost fine particles was significantly reduced. Finally, it was confirmed that void filling ratio was able to effectively describe the internal stability of gap-graded soils subject to different levels of hydraulic gradient.


Assuntos
Solo , Movimentos da Água , Permeabilidade
7.
Arch Environ Contam Toxicol ; 78(3): 392-400, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31932858

RESUMO

Volatile organic compounds (VOCs) are involved in the formation of ozone formation, which plays a significant role in regional air contamination and poses a great threat to human health. The VOCs were collected from the urban area of Hefei city via an off-line sampling method (SUMMA canister) and determined by gas chromatography-mass spectrometer. The average concentrations of VOCs were 17.65 ± 28.36 ppbv, which were mainly contributed by aromatics (10.02 ± 13.37 ppbv), haloalkane (5.37 ± 8.90 ppbv), ally halide (1.25 ± 3.36 ppbv), and aryl halid (1.02 ± 2.73 ppbv). According to the principal component analysis, three major sources were identified, including solvent use, vehicle exhaust, and industrial release, accounting for 70.6% of the total variance of the data. Health risk assessment was utilized to evaluate the potential adverse health effects of the individual VOC. The total hazard ratio in the selected area was higher than 1, where could pose health threat to exposed population. The cancer risk for benzene, carbon tetrachloride, trichloromethane, and 1, 2-dichloroethane were 4.8 × 10-5, 4.5 × 10-5, 3.3 × 10-5, and 2.5 × 10-5, respectively, indicating definite health risks.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Ozônio/análise , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise , China , Cidades , Humanos , Indústrias , Análise de Componente Principal , Medição de Risco
8.
Nanoscale Res Lett ; 14(1): 96, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30874973

RESUMO

Anaplastic thyroid cancer (ATC) comprises approximately 2% of all thyroid cancers, and its median survival rate remains poor because of its resistance to conventional therapy. Vascular endothelial growth factor receptor (VEGFR)-targeted therapeutics-loaded mesoporous silica nanoparticles represent a major advance for angiogenesis imaging and inhibition in lethal cancers. In the present study, we aimed to assess whether 131I-labeled anti-VEGFR2 targeted mesoporous silica nanoparticles would have antitumor efficacy in an ATC tumor-bearing nude mouse model. Using in vitro and in vivo studies, we investigated the increased targeting ability and retention time in the anti-VEGFR2 targeted group using confocal microscopy and a γ counter. The tumor tissue radioactivity of the anti-VEGFR2 targeted group at 24 and 72 h after intratumoral injection was significantly higher than that of the non-targeted groups (all P < 0.05). Moreover, we found that radioactive accumulation was obvious even at 3 week post-injection in the anti-VEGFR2 targeted group via single-photon emission computed tomography/computed tomography, which was not seen at 3 day post-injection in the Na131I group. Meanwhile, compared with the non-targeted group, tumor growth in the targeted group was significantly inhibited, without causing apparent systemic toxic effects. Additionally, the median survival time in the targeted group (41 days) was significantly prolonged compared with that in the non-targeted (34 days) or Na131I (25 days) groups (both P < 0.01). Our data support the view that the as-developed 131I-labeled anti-VEGFR2 targeted mesoporous silica nanoparticles showed promising results in ATC tumor-bearing mouse model and such an approach might represent a novel therapeutic option for ATC.

9.
Artigo em Inglês | MEDLINE | ID: mdl-30029535

RESUMO

Polybrominated diphenyl ethers (PBDEs) were extensively investigated in water, sediment, and biota samples collected from Chaohu Lake basin in China. The total concentrations of eight PBDEs (Σ8PBDEs) were in the ranges of 0.11⁻4.48 ng/L, 0.06⁻5.41 ng/g, and 0.02⁻1.50 ng/g dry weight (dw) in the water, sediment, and biota samples, respectively. The concentrations showed wide variations in the monitoring area, while the congener profiles in all the water, sediment, and biota samples were generally characterized by only a few compounds, such as BDE-47, BDE-99, and/or BDE-209. The spatial analysis depicted a decreasing trend of PBDEs from west to east Chaohu Lake, consistent with regional industrialization degree. The distributions of PBDE congeners in the biota samples were similar to the compositional profiles in the water, which were dominated by BDE-47 and/or BDE-99. Nevertheless, BDE-47 and BDE-153 in the brain tissue showed a higher accumulative potential than PBDEs in other tissues as well as the whole body, with 96% relative contribution of Σ8PBDEs. The noncarcinogenic risk values estimated for BDE-47, BDE-99, and BDE-153 indicated that the specific risk associated with the studied water and foodstuffs is limited. However, there is a potential mixture ecotoxicity at three trophic levels at some sampling points in the water, which should draw considerable attention.


Assuntos
Poluição Ambiental/análise , Água Doce/análise , Sedimentos Geológicos/análise , Éteres Difenil Halogenados/análise , Lagos/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental/métodos , Medição de Risco
10.
Int J Med Robot ; 14(6): e1942, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30058772

RESUMO

BACKGROUND: Unlike a manual surgical instrument, a surgical instrument used in robot-assisted minimally invasive surgery (MIS) is configured with a wrist to improve flexibility in surgical operation. However, this configuration has a shortcoming that leads to coupled motion between the wrist and end-effector. METHODS: Three methods are presented to eliminate the coupled motion between the wrist and end-effector. The three methods are compared via the decoupled motion characteristic, and the third method is applied to design four surgical instruments. Several experiments are done to validate the effectiveness of these surgical instruments. RESULTS: These improved surgical instruments create decoupled motion. The results of experiments on the removal of gall bladder and kidney are excellent, which validates the effectiveness of decoupled surgical instruments. CONCLUSIONS: Improved surgical instruments without coupled motion are developed and have a promising clinical application in MIS.


Assuntos
Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Movimento (Física) , Robótica/instrumentação , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/métodos , Instrumentos Cirúrgicos , Animais , Desenho de Equipamento , Vesícula Biliar/cirurgia , Humanos , Rim/cirurgia , Reprodutibilidade dos Testes , Suínos
11.
Int J Med Robot ; 13(1)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27291158

RESUMO

BACKGROUND: It is difficult for surgeons to exert appropriate forces during delicate operations due to lack of force feedback in robot-assisted minimally invasive surgery (RMIS). A 4-DOF surgical grasper with a modular wrist and 6-axis force sensing capability is developed. METHODS: A grasper integrated with a miniature force and torque sensor based on the Stewart platform is designed, and a cable tension decomposition mechanism is designed to alleviate influence of the cable tension to the sensor. A modularized wrist consisting of four joint units is designed to facilitate integration of the sensor and eliminate coupled motion of the wrist. RESULTS: Sensing ranges of this instrument are ±10 N and ±160 N mm, and resolutions are 1.2% in radial directions, 5% in axial direction, and 4.2% in rotational directions. An ex vivo experiment shows that this instrument prototype successfully measures the interaction forces. CONCLUSIONS: A 4-DOF surgical instrument with modular joints and 6-axis force sensing capability is developed. This instrument can be used for force feedback in RMIS. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Robótica/instrumentação , Instrumentos Cirúrgicos , Animais , Materiais Biocompatíveis , Fenômenos Biomecânicos , Calibragem , Desenho de Equipamento , Retroalimentação , Humanos , Rim/cirurgia , Movimento (Física) , Pressão , Reprodutibilidade dos Testes , Estresse Mecânico , Suínos , Torque , Punho
12.
Biomed Mater Eng ; 26 Suppl 1: S665-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26406062

RESUMO

Aiming at the hand rehabilitation of stroke patients, a wearable hand exoskeleton with circuitous joint is proposed. The circuitous joint adopts the symmetric pinion and rack mechanism (SPRM) with the parallel mechanism. The exoskeleton finger is a serial mechanism composed of three closed-chain SPRM joints in series. The kinematic equations of the open chain of the finger and the closed chains of the SPRM joints were built to analyze the kinematics of the hand rehabilitation exoskeleton. The experimental setup of the hand rehabilitation exoskeleton was built and the continuous passive motion (CPM) rehabilitation experiment and the test of human-robot interaction force measurement were conducted. Experiment results show that the mechanical design of the hand rehabilitation robot is reasonable and that the kinematic analysis is correct, thus the exoskeleton can be used for the hand rehabilitation of stroke patients.


Assuntos
Exoesqueleto Energizado , Mãos/fisiopatologia , Modelos Biológicos , Terapia Passiva Contínua de Movimento/instrumentação , Amplitude de Movimento Articular , Robótica/instrumentação , Fenômenos Biomecânicos , Simulação por Computador , Desenho Assistido por Computador , Análise de Falha de Equipamento , Humanos , Sistemas Homem-Máquina , Terapia Passiva Contínua de Movimento/métodos , Desenho de Prótese , Estresse Mecânico , Terapia Assistida por Computador/instrumentação , Terapia Assistida por Computador/métodos
13.
Ecotoxicol Environ Saf ; 108: 16-22, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25038267

RESUMO

Polybrominated diphenyl ethers (PBDEs) are of great environmental concern due to bioaccumulation and biomagnification in different food chains. However, significant biotransformation of some congeners via reductive debromination has been observed during in vivo and in vitro laboratory exposures. Little is known about the fate of 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153) in fish. In the present study, crucian carp (Carassius auratus) were exposed to BDE-153 at a concentration of 10µg/g in food for 28 days. BDE-153 and its metabolites in different tissues were identified and quantified using gas chromatography coupled with tandem mass spectrometry and ultra-high performance liquid chromatography coupled with tandem mass spectrometry. In addition to eight debrominated metabolites, four oxidative metabolites were detected 4'-hydroxy-2,2',4,5'-tetra-BDE, 6-hydroxy-2,2',4,4'-tetra-BDE, 2,4-dibromophenol and 2,4,6-tribromophenol. With regard to the concentrations of BDE-153 and the major metabolites, the contribution order of different tissues was bile>brain>liver>gill>muscle. The highest concentrations of BDE-153 and metabolite 2,2',4,4'-tetrabromodiphenyl ether were detected in bile at 808ng/g and 157ng/g, respectively. Our results suggested that three possible metabolic pathways of BDE-153 occurred in crucian carp via dietary exposure: debromination, hydroxylation and cleavage of the diphenyl ether bond. These findings indicated evidence of the bioavailability of BDE-153 from food in the form of debrominated metabolites and oxidative metabolites in freshwater fish, which is critical to understanding the complete risks associated with PBDE bioaccumulation and metabolism in humans and wildlife.


Assuntos
Carpa Dourada/metabolismo , Éteres Difenil Halogenados/metabolismo , Bifenil Polibromatos/metabolismo , Animais , Biotransformação , Dieta , Água Doce , Éteres Difenil Halogenados/farmacocinética , Hidroxilação , Fígado/metabolismo , Bifenil Polibromatos/farmacocinética , Espectrometria de Massas em Tandem , Distribuição Tecidual
14.
Chem Commun (Camb) ; 49(41): 4697-9, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23589825

RESUMO

An efficient and diastereoselective Pd-catalyzed method of allylation of aldehydes with 3-bromomethyl-5H-furan-2-one is described. The proposed method allows the synthesis of ß-(hydroxymethylaryl/alkyl)-α-methylene-γ-butyrolactones with a syn relative configuration for the first time.


Assuntos
4-Butirolactona/análogos & derivados , Aldeídos/química , Furanos/química , Paládio/química , 4-Butirolactona/síntese química , 4-Butirolactona/química , Catálise , Estereoisomerismo
15.
Oncol Lett ; 5(2): 669-674, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23420532

RESUMO

Radioiodine is a routine therapy for differentiated thyroid cancers. Non-thyroid cancers may be treated with radio-iodine following transfection with the human sodium/iodide symporter (hNIS) gene. The glial fibrillary acidic protein (GFAP) promoter is an effective tumor-specific promoter for gene expression and thus may be useful in targeted gene therapy of malignant glioma. The present study used GFAP promoter-modulated expression of the hNIS gene in an experimental model of radioiodine-based treatment for malignant glioma. Cells were transfected using a recombination adeno-virus and evaluated in cells by studying the transfected transgene expression through western blot analysis, (125)I uptake and efflux, clonogenicity following (131)I treatment and radioiodine therapy using a U87 xenograft nude mouse model. Following transfection with the hNIS gene, the cells showed 95-70-fold higher (125)I uptake compared with the control cells transfected with Ad-cytomegalovirus (CMV)-enhanced green fluorescent protein (EGFP). The western blotting revealed bands of ∼70, 49 and 43 kDa, consistent with the hNIS, GFAP and ß-actin proteins. The clonogenic assay indicated that, following exposure to 500 µCi of (131)I-iodide for 12 h, >90% of cells transfected with the hNIS gene were killed. Ad-GFAP-hNIS-transfected and 2 mCi (131)I-injected U87 xenograft nude mice survived the longest of the three groups. The hNIS-expressing tumor tissue accumulated (99m)TcO(4) rapidly within 30 min of it being intraperitoneally injected. The experiments demonstrated that effective (131)I therapy was achieved in the malignant glioma cell lines following the induction of tumor-specific iodide uptake activity by GFAP promoter-directed hNIS gene expression in vitro and in vivo. (131)I therapy retarded Ad-GFAP-hNIS transfected-tumor growth following injection with (131)I in U87 xenograft-bearing nude mice.

16.
Nucl Med Commun ; 31(5): 398-404, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20084038

RESUMO

OBJECTIVES: Target-to-background ratio (T/B) is a commonly used semiquantitative index in F-FDG dual-head coincidence single-photon emission computed tomography (c-SPECT) imaging. However, because of different methods of measurement, T/B varies. This study used F-FDG c-SPECT/CT imaging of mediastinal lesions to analyze the impact of different backgrounds for determining T/Bs. METHODS: Thirty-five patients with mediastinal lesions underwent thoracic F-FDG c-SPECT/CT with 1-inch crystals. According to integrated CT, five types of backgrounds were precisely positioned as airway, fat, mediastinal space, vascular blood, and heart areas. Corresponding T/Bs (T/BA, T/BF, T/BM, T/BV, and T/BH) of benign and malignant lesions were calculated. Two-way analysis of variance, receiver-operating characteristic curves, and coefficient of variation were performed for statistical analyses. RESULTS: Seventeen benign lesions and 23 malignant lesions were identified in patients with histological confirmation. Only T/BA was significantly different from other T/Bs in both the benign and malignant groups; yet, there were no significant differences in the remaining T/Bs (P<0.01). On the basis of receiver-operating characteristic curves, cutoff values, sensitivity, specificity, positive predictive value and negative predictive value, the accuracy of diagnosis followed the order of T/BV>T/BM> T/BA>T/BF>T/BH, and T/BV showed optimal sensitivity (87.0%), specificity (76.5%), and accuracy (82.5%) of diagnosis. Vascular blood and mediastinal space areas, which were in the same homogeneous subset, possessed the significantly lowest coefficient of variation, indicating good homogeneity in the regions. CONCLUSION: Choosing different backgrounds has a great impact on the diagnostic accuracies of F-FDG c-SPECT/CT imaging of mediastinal lesions. The large blood vessel area is the best background choice for optimization of T/B calculation.


Assuntos
Fluordesoxiglucose F18 , Neoplasias do Mediastino/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
Hell J Nucl Med ; 12(3): 276-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19936344

RESUMO

Urine bladder diverticula are usually asymptomatic, therefore they are incidentally diagnosed during examinations for other purposes. A Chinese patient, with a history of pulmonary adenocarcinoma first underwent a technetium-99m methylene diphosphonate whole-body bone scan. In addition to multiple skeletal metastases, abnormal shape of the urine bladder was also noted, which overlapped the superior ramus of the right pubic bone. In order to: a) better delineate the shape and structure of the urine bladder; b) visualize the pubic bone and c) detect the exact location and structural changes of skeletal lesions in the lumbosacral region, single photon emission tomography/computerized tomography (SPET/CT) scan of this region was performed immediately, and demonstrated: a) a big urine bladder diverticulum in the right hemipelvis; b) structural changes of skeletal metastases while metastases in the pubic bone were ruled out. An overview of the etiology, histopathology, complications, management and imaging of urine bladder diverticulum is also presented. We consider our case the first to be diagnosed by SPET/CT and differentiated from metastases of the overlapping bone in a 69 years old female.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/secundário , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/secundário , Divertículo/diagnóstico , Neoplasias Pulmonares/diagnóstico , Doenças da Bexiga Urinária/diagnóstico , Adenocarcinoma/complicações , Idoso , Neoplasias Ósseas/complicações , Diagnóstico Diferencial , Divertículo/congênito , Feminino , Humanos , Achados Incidentais , Neoplasias Pulmonares/complicações , Compostos Radiofarmacêuticos , Técnica de Subtração , Medronato de Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Doenças da Bexiga Urinária/congênito
18.
Clin Nucl Med ; 34(9): 615-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19692828

RESUMO

We present a case of functioning metastatic follicular thyroid carcinoma (FTC) causing severe thyrotoxicosis despite four years 12 iodine-131 therapies (1.461 Ci cumulatively). Initially, the patient had ostalgia and fracture in the right femur. Surgery-confirmed metastatic bone FTC and thyroidectomy-confirmed FTC. One month later, iodine-131 treatment commenced. During the follow-up, different metastatic sites showed different outcomes. Lung metastases disappeared, a thigh metastasis persisted, a new metastasis in the head occurred and pelvic metastases deteriorated into a huge mass elevating thyroglobulin and causing thyrotoxicosis within 3 months. Presurgical PET/CT also demonstrated the massiveness of the pelvic metastases. Thyrotoxicosis disappeared after surgical removal of the pelvic lesion.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/radioterapia , Tireotoxicose/etiologia , Adulto , Feminino , Humanos , Metástase Neoplásica , Tomografia por Emissão de Pósitrons , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Tomografia Computadorizada por Raios X
20.
Ann Nucl Med ; 23(3): 317-20, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19340525

RESUMO

Parathyroid lipoadenoma is an unusual cause of primary hyperparathyroidism. Only a few earlier reports have documented parathyroid imaging in diagnostic studies of parathyroid lipoadenoma. Our case was a 27-year-old man, who was originally diagnosed with primary hyperparathyroidism. He underwent a Tc-99m sestamibi dual-phase parathyroid imaging study, which revealed a right-inferior parathyroid hyperfunctional lesion. The first operation removed a lesion of 1.5 cm in diameter in the area, and parathyroid lipoadenoma was diagnosed by pathology. However, hypercalcemia persisted. One week later, a Tc-99m sestamibi whole-body scan and another dual-phase imagining were performed, which demonstrated a residual lesion in the inferior part of the right thyroid region, while no ectopic lesion was found. A second surgery was performed and pathological diagnosis was confirmed as parathyroid lipoadenoma again. Our case demonstrated that although hyperfunctional parathyroid lipoadenoma is rare, Tc-99m sestamibi parathyroid imaging is reliable in locating the lesion for surgical purposes. And Tc-99m sestamibi imaging is useful in reoperative and persistent hyperparathyroidism situations as well.


Assuntos
Adenoma/diagnóstico por imagem , Neoplasias das Paratireoides/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Adenoma/patologia , Adenoma/cirurgia , Adulto , Humanos , Masculino , Neoplasias das Paratireoides/patologia , Neoplasias das Paratireoides/cirurgia , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
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