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1.
Clin Nucl Med ; 45(2): 148-150, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31876825

RESUMO

A 43-year-old woman presented with progressive muscle weakness and myalgia for 1 month. Laboratory tests revealed the elevation of myogenic enzymes. MRI of the thighs demonstrated a pattern of edema for inflammatory myopathy. Electromyography showed diffuse myopathic disorder, and muscle biopsy indicated polymyositis. F-FDG PET/CT was performed to investigate the potential paraneoplastic syndrome and revealed a soft tissue lesion with F-FDG avidity in the right anterior mediastinum, as well as diffusely increased activity throughout the body muscles. The patient's symptoms and biochemical abnormalities were gradually relieved after the tumor resection, and the histopathology indicated a type AB thymoma.


Assuntos
Polimiosite/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Timoma/diagnóstico por imagem , Neoplasias do Timo/diagnóstico por imagem , Adulto , Feminino , Fluordesoxiglucose F18 , Humanos , Polimiosite/complicações , Compostos Radiofarmacêuticos , Timoma/complicações , Neoplasias do Timo/complicações
2.
Sci Rep ; 9(1): 19363, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852947

RESUMO

The objective of this study was to illustrate our specific findings for intrahepatic cholangiocarcinoma (ICC) lesions on contrast-enhanced ultrasound (CEUS). In this study, 21 patients at our hospitals with pathologically proven ICC and CEUS data were retrospectively enrolled. General clinical data of the patients, and features of lesions on conventional and contrast-enhanced ultrasound were recorded. Two experienced radiologists retrospectively reviewed all images by consensus. On gray-scale sonography, hypoechoic, isoechoic and hyperechoic lesions accounted for 85.7%, 9.5% and 4.8%, respectively, of all lesions. Hypovascular patterns were found for 95.2% of the lesions on color Doppler flow imaging. During the arterial phase of CEUS, heterogeneous hyperenhancement, homogeneous hyperenhancement, rim-like hyperenhancement, isoenhancement and hypoenhancement were observed for 61.9%, 19.0%, 9.5%, 4.8%, 4.8% of the lesions, respectively. During the portal venous and late phases, 85.7% and 95.2% of the lesions, respectively, exhibited hypoenhancement. In addition, 66.7% of the ICC lesions exhibited washed-out interiors but little decrease in enhancement at the periphery during the portal venous phase, resulting in the formation of a hyperenhanced peripheral rim. In conclusion, the rim sign in the portal venous phase of CEUS could help diagnose ICC. This trait could be related to the infiltrating growth pattern of ICC.

3.
Clin Nucl Med ; 44(9): 748-749, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31107752

RESUMO

Bilateral adrenal masses were found by ultrasound on a 55-year-old man with sudden onset of chest distress and palpitation after drinking alcohol. After the negative laboratory tests of plasma catecholamine and urinary vanillylmandelic acid, the F-FDG PET/CT revealed extremely intense metabolic activity in the bilateral adrenal lesions, and the subsequent I-meta-iodobenzylguanidine scintigraphy also showed increased radioactivity in the lesions. The pathology of surgery confirmed the diagnosis of bilateral pheochromocytomas.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/metabolismo , Fluordesoxiglucose F18 , Feocromocitoma/diagnóstico por imagem , Feocromocitoma/metabolismo , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Neoplasias das Glândulas Suprarrenais/patologia , Glândulas Suprarrenais/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Feocromocitoma/patologia
4.
Neuroimage Clin ; 22: 101795, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30991617

RESUMO

While the ApoE ε4 allele is a known risk factor for mild cognitive impairment (MCI) and Alzheimer's disease, brain region specific effects remain elusive. In this study, we investigate whether the ApoE ε4 allele exhibits brain region specific effects in longitudinal glucose uptake among patients with MCI from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Preprocessed FDG PET images, MRIs, and demographic information were downloaded from the ADNI database. An iterative reblurred Van Cittertiteration method was used for partial volume correction (PVC) on all PET images. Structural MRIs were used for PET spatial normalization and region of interest (ROI) definition in standard space. Longitudinal changes in ROI FDG standardized uptake value ratio (SUVR) relative to cerebellum in 24 ApoE ε4 carriers and 24 age-matched ApoE ε4 non-carriers were measured for up to 84-months (median 72 months, SD = 11.2 months) and compared using a generalized linear mixed effects model controlling for gender, education, baseline age, and follow-up period. Additionally, voxelwise analysis was performed by implementing a paired t-test comparing matched baseline and 72 month FDG SUVR images in ApoE carriers and non-carriers separately. Results with PVC were compared with ones from non-PVC based analysis. After applying PVC, the superior fontal, parietal, lateral temporal, medial temporal, caudate, thalamus, and post-cingulate, and amygdala regions had greater longitudinal decreases in FDG uptake in ApoE ε4 carriers with MCI compared to non-carriers with MCI. Similar forebrain and limbic clusters were found through voxelwise analysis. Compared to the PVC based analysis, fewer significant ApoE-associated regions and clusters were found in the non-PVC based PET analysis. Our findings suggest that the ApoE ε4 genotype is associated with a longitudinal decline in glucose uptake in 8 forebrain and limbic brain regions in the context of MCI. In conclusion, this 84-months longitudinal FDG PET study demonstrates a novel ApoE ε4-associated brain-region specific glucose metabolism pattern in patients with MCI. Partial volume correction improved FDG PET quantification.


Assuntos
Apolipoproteína E4/genética , Apolipoproteínas E/genética , Encéfalo/metabolismo , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Glucose/metabolismo , Neuroimagem/métodos , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18 , Humanos , Estudos Longitudinais , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons
5.
Clin Nucl Med ; 44(6): 489-490, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30829860

RESUMO

F-FDG PET/CT was performed on a 70-year-old man to stage the newly diagnosed multiple myeloma. A hypermetabolic lesion in the gallbladder fundus was revealed incidentally and suspected for gallbladder carcinoma, but was finally proven to be a cholesterol granuloma by the pathology of cholecystectomy.


Assuntos
Carcinoma/diagnóstico por imagem , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Granuloma/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Idoso , Diagnóstico Diferencial , Fluordesoxiglucose F18 , Humanos , Masculino , Compostos Radiofarmacêuticos
6.
Clin Nucl Med ; 44(4): 332-333, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30688732

RESUMO

A 41-year-old woman presented with irregular vaginal bleeding, and a vaginal tumor was found and proved to be a clear cell carcinoma by biopsy. An F-FDG PET/CT was performed to exclude its metastatic possibility, which showed the vaginal tumor was the only lesion with F-FDG avidity. The vaginectomy and hysterectomy were performed to resect the lesion, and primary clear cell carcinoma of the vagina was finally diagnosed.


Assuntos
Fluordesoxiglucose F18 , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Neoplasias Vaginais/diagnóstico por imagem , Adulto , Feminino , Humanos , Metástase Neoplásica , Neoplasias Vaginais/patologia , Neoplasias Vaginais/cirurgia
7.
Mol Imaging Biol ; 21(2): 286-296, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29916116

RESUMO

PURPOSE: Tc-99m- and I-131-labeled arginine-arginine-leucine (RRL) peptides have shown the feasibility of tumor imaging in our previous studies. However, there have been no reports using RRL peptide for positron emission tomography (PET) imaging. In this study, RRL was radiolabeled with Ga-68 under optimized reaction conditions to develop a better specific and effective tumor imaging agent. PROCEDURES: RRL was synthesized and conjugated to a bifunctional chelating agent (DOTA-NHS), then radiolabeled with Ga-68. Labeling yield was optimized by varying pH, temperature, and reaction time and the stability was evaluated in human fresh serum. Cellular uptakes of [68Ga]DOTA-RRL and FITC-conjugated RRL in HepG2 cells were evaluated using a gamma counter, confocal microscopy, and flow cytometry. PET images and biodistribution were performed in HepG2 tumor-bearing mice after injection of [68Ga]DOTA-RRL or [68Ga]GaCl3 at different time points. Further, blocking study was investigated using cold RRL. RESULTS: The labeling yield of [68Ga]DOTA-RRL was 80.6 ± 3.9 % with a pH of 3.5-4.5 at 100 °C for 15 min. The cellular uptake of [68Ga]DOTA-RRL in HepG2 cells was significantly higher than that of [68Ga]GaCl3 (P < 0.05). Moreover, the high fluorescent affinity of FITC-conjugated RRL in HepG2 cells was shown using confocal microscopy and flow cytometry. After injection of [68Ga]DOTA-RRL in HepG2 tumor-bearing mice, tumor regions exhibited high radioactive accumulation over 120 min and the highest uptake at 30 min. After blocked with cold RRL, HepG2 tumors could not be visualized. [68Ga]GaCl3 was unable to show tumor images at any time point. The biodistribution results confirmed the PET imaging and blocking results. CONCLUSIONS: Our study successfully prepared [68Ga]DOTA-RRL with a high labeling yield under the optimized reaction conditions and demonstrated its potential role as a PET imaging agent for tumor-targeted diagnosis.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Radioisótopos de Gálio/química , Neoplasias Hepáticas/diagnóstico por imagem , Peptídeos/química , Tomografia por Emissão de Pósitrons , Animais , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Camundongos , Peptídeos/sangue , Distribuição Tecidual
8.
Clin Nucl Med ; 44(2): 169-170, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30516669

RESUMO

An F-FDG PET/CT was performed on a 47-year-old man diagnosed as multiple myeloma with diffuse bone marrow infiltration on pathology. PET/CT findings presented as a pattern of skeletal "superscan," including diffuse and prominent hypermetabolism throughout the axial and proximal appendicular skeleton, which all alleviated after 5 cycles of chemotherapy.


Assuntos
Osso e Ossos/diagnóstico por imagem , Fluordesoxiglucose F18 , Mieloma Múltiplo/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Medula Óssea/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia
9.
Clin Nucl Med ; 43(12): 941-942, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30300198

RESUMO

An F-FDG PET/CT was performed on a 74-year-old woman with pancreatic carcinoma and liver metastases. Occult giant cell arteritis, involving the aorta, truncus brachiocephalicus, subclavian arteries, axillaries, external carotid arteries, vertebral arteries, and superficial temporal arteries, was accidentally revealed.


Assuntos
Arterite de Células Gigantes/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Idoso , Feminino , Fluordesoxiglucose F18 , Arterite de Células Gigantes/complicações , Humanos , Achados Incidentais , Neoplasias Pancreáticas/complicações , Compostos Radiofarmacêuticos
10.
Clin Nucl Med ; 43(9): 697-698, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30080186

RESUMO

A 46-year-old woman suffering from lower extremity weakness, dysarthria, dysphagia, dyspnea, and dry mouth was suspected of having Lambert-Eaton myasthenic syndrome based on the characteristic electromyographic abnormalities of right ulnar nerve, which demonstrated reduced resting compound muscle action potential amplitude and greater than 100% incremental change in high-frequency repetitive nerve stimulation. An F-FDG PET/CT was performed to detect the underlying neoplasm and revealed a retroperitoneal soft tissue mass with high F-FDG avidity in the left iliac fossa. The patient's symptoms were prominently relieved after the tumor resection, and the histopathology indicated a small cell carcinoma.


Assuntos
Carcinoma de Células Pequenas/diagnóstico por imagem , Síndrome Miastênica de Lambert-Eaton/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Neoplasias Retroperitoneais/diagnóstico por imagem , Carcinoma de Células Pequenas/complicações , Feminino , Fluordesoxiglucose F18 , Humanos , Síndrome Miastênica de Lambert-Eaton/complicações , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Neoplasias Retroperitoneais/complicações
11.
Clin Nucl Med ; 43(8): 617-618, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29894336

RESUMO

An F-FDG PET/CT was performed on a 43-year-old woman with photosensitive skin rash, abnormal liver function, and pancytopenia, which demonstrated prominent hepatomegaly, splenomegaly, and diffuse liver F-FDG avidity. The liver biopsy revealed intrahepatic cholestasis with biliary fibrosis resulting from the deposition of protoporphyrin. X-linked erythroid-specific 5-aminolevulinate synthase gene analysis proved the diagnosis of X-linked protoporphyria.


Assuntos
Fluordesoxiglucose F18/metabolismo , Fígado/diagnóstico por imagem , Fígado/metabolismo , Porfirias Hepáticas/diagnóstico por imagem , Porfirias Hepáticas/genética , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Adulto , Feminino , Humanos , Porfirias Hepáticas/metabolismo
12.
R Soc Open Sci ; 5(4): 172002, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29765653

RESUMO

With the growing depletion of wood-based materials and concerns over emissions of formaldehyde from traditional wood fibre composites, there is a desire for environment-friendly binders. Herein, we report a green wood fibre composite with specific bonding strength and water resistance that is superior to a commercial system by using wood fibres and chitosan-based adhesives. When the mass ratio of solid content in the adhesive and absolute dry wood fibres was 3%, the bonding strength and water resistance of the wood fibre composite reached the optimal level, which was significantly improved over that of wood fibre composites without adhesive and completely met the requirements of the Chinese national standard GB/T 11718-2009. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) characterizations revealed that the excellent performance of the binder might partly be due to the amide linkages and hydrogen bonding between wood fibres and the chitosan-based adhesive. We believe that this strategy could open new insights into the design of environment-friendly wood fibre composites with high bonding strength and water resistance for multifunctional applications.

13.
Clin Nucl Med ; 43(6): 464-465, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29561527

RESUMO

A 36-year-old woman suffering from oral ulcerations, skin rash, and dyspnea was suspected of having paraneoplastic pemphigus. An F-FDG PET/CT was performed to detect the underlying neoplasms and revealed an F-FDG-avid mass in the lower right retroperitoneum. The mucocutaneous lesions and dyspnea were relieved after the tumor excision, and the pathology indicated Castleman disease.


Assuntos
Hiperplasia do Linfonodo Gigante/diagnóstico por imagem , Pênfigo/etiologia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Hiperplasia do Linfonodo Gigante/complicações , Feminino , Fluordesoxiglucose F18 , Humanos , Pessoa de Meia-Idade , Pênfigo/patologia , Compostos Radiofarmacêuticos
14.
Chin Med J (Engl) ; 130(22): 2686-2690, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29133756

RESUMO

BACKGROUND: Overexpression and constitutive activation of signal transducer and activator of transcription (STAT) 3 have been suggested in the tumorigenesis of many human cancers, including multiple carcinomas, melanoma, and lymphoma. The diagnosis of hepatocellular carcinoma (HCC) in lobectomy specimens is usually straightforward, but distinguishing cirrhosis from well-differentiated HCC can be challenging in core biopsies. Our aims were to investigate the expression level of STAT3 and phosphorylated STAT3 (pSTAT3) in HCC and cirrhosis, and the application of STAT3 in the differential diagnosis of HCC and cirrhosis. METHODS: Sixty cases were divided into three groups: patients with HCC only (Group 1), HCC and cirrhosis (Group 2), and cirrhosis only (Group 3). Formalin-fixed and paraffin-embedded tissue sections were stained immunohistochemically for STAT3, pSTAT3, and CD163. The values obtained from the tissue sections of each group were compared in statistical analysis. RESULTS: STAT3 showed a high level in HCC and was a significant marker for differentiating HCC from cirrhosis (P < 0.0001). The odds ratio between HCC and cirrhosis increased 34.4 times when the intensity of STAT3 increased by 1 level. Spearman's correlation and Chi-square tests also demonstrated that expression level of STAT3 did not correlate with age, gender, or the presence of a cirrhotic background. CONCLUSIONS: STAT3 staining differs significantly in HCC and cirrhosis. The findings reinforce the role of STAT3 in the tumorigenesis of HCC and provide a useful marker to differentiate HCC from cirrhosis in challenging liver biopsies.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fator de Transcrição STAT3/metabolismo , Adulto , Carcinoma Hepatocelular/patologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Feminino , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Fosforilação , Fator de Transcrição STAT3/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
15.
World J Gastroenterol ; 23(28): 5179-5186, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28811712

RESUMO

AIM: To determine the pathogenesis and potential single nucleotide polymorphisms (SNPs) as screening sites for colonic polyps, colon cancer and ulcerative colitis, and to analyze the possible association between these genetic polymorphisms and the three diseases. METHODS: We evaluated genetic polymorphisms in 144 newly diagnosed colonic polyp patients, 96 colon cancer patients and 44 ulcerative colitis patients. The four SNPs genotyped were rs4809957, rs6068816, rs6091822 and rs8124792. The control group consisted of 504 East Asians enrolled in the 1000 Genomes Project. Correlations between CYP24A1 SNPs and the diseases were analyzed by Fisher's exact probability test. RESULTS: CYP24A1 polymorphisms rs4809957 A/G and rs6068816 C/T showed a statistically significant association with risk of the three diseases, when both the genotypes and allele frequencies were considered. With regard to rs6091822 G/T, all three diseases were related to risk allele carriers (GT + TT) vs wild-type (GG), but the associations between the allele frequencies and the diseases were not significant. The risk of colonic polyps and colon cancer was related to the allele frequencies of rs8124792 G/A, and this association remained for genotype frequencies of this SNP. CONCLUSION: Four SNPs are related to the risk of colonic polyps and colon cancer. G allele in rs6091822 G/T may play an anti-cancer role only if it is homozygous. The A allele, which is a minor component of rs8124792, may be indicated in the diagnosis of colonic polyps or colon cancer rather than ulcerative colitis.


Assuntos
Colite Ulcerativa/genética , Neoplasias do Colo/genética , Pólipos do Colo/genética , Frequência do Gene/genética , Vitamina D3 24-Hidroxilase/genética , Adulto , Idoso , Grupo com Ancestrais do Continente Asiático/genética , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Detecção Precoce de Câncer/métodos , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
16.
Int J Cancer ; 141(6): 1240-1248, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28580707

RESUMO

Lung cancer is primarily caused by cigarette smoking and the leading cancer killer in the USA and across the world. Early detection of lung cancer by low-dose CT (LDCT) can reduce the mortality. However, LDCT dramatically increases the number of indeterminate pulmonary nodules (PNs), leading to overdiagnosis. Having a definitive preoperative diagnosis of malignant PNs is clinically important. Using microarray and droplet digital PCR to directly profile plasma miRNA expressions of 135 patients with PNs, we identified 11 plasma miRNAs that displayed a significant difference between patients with malignant versus benign PNs. Using multivariate logistic regression analysis of the molecular results and clinical/radiological characteristics, we developed an integrated classifier comprising two miRNA biomarkers and one radiological characteristic for distinguishing malignant from benign PNs. The classifier had 89.9% sensitivity and 90.9% specificity, being significantly higher compared with the biomarkers or clinical/radiological characteristics alone (all p < 0.05). The classifier was validated in two independent sets of patients. We have for the first time shown that the integration of plasma biomarkers and radiological characteristics could more accurately identify lung cancer among indeterminate PNs. Future use of the classifier could spare individuals with benign growths from the harmful diagnostic procedures, while allowing effective treatments to be immediately initiated for lung cancer, thereby reduces the mortality and cost. Nevertheless, further prospective validation of this classifier is warranted.


Assuntos
Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico por imagem , MicroRNAs/sangue , Nódulo Pulmonar Solitário/sangue , Nódulo Pulmonar Solitário/diagnóstico por imagem , Idoso , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/genética , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Pulmonares/genética , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Nódulo Pulmonar Solitário/genética
17.
Molecules ; 22(2)2017 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-28165399

RESUMO

(1) Background: The great potential of RNA interference (RNAi)-based gene therapy is premised on the effective delivery of small interfering RNAs (siRNAs) to target tissues and cells. Hence, we aimed at developing and examining a novel integrin αvß3-specific delivery carrier for targeted transfection of siRNA to malignant tumor cells; (2) Methods: Arginine-glycine-aspartate motif (RGD) was adopted as a tissue target for specific recognition of integrin αvß3. To enable siRNA binding, a chimeric peptide was synthesized by adding nonamer arginine residues (9R) at the carboxy terminus of cyclic-RGD dimer, designated as c(RGD)2-9R. The efficiency of 9R peptide transferring siRNA was biologically evaluated in vitro by flow cytometry, confocal microscopy, and Western blot; (3) Results: An optimal 10:1 molar ratio of c(RGD)2-9R to siRNA was confirmed by the electrophoresis on agarose gels. Both the flow cytometry and confocal microscopy results testified that transfection of c(RGD)2-9R as an siRNA delivery carrier was obviously higher than the naked-siRNA group. The results of Western blot demonstrated that these 9R peptides were able to transduce siRNA to HepG2 cells in vitro, resulting in efficient gene silencing; and (4) Conclusion: The chimeric peptide of c(RGD)2-9R can be developed as an effective siRNA delivery carrier and shows potential as a new strategy for RNAi-based gene therapy.


Assuntos
Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Integrina alfaVbeta3/química , RNA Interferente Pequeno/química , Linhagem Celular Tumoral , Células Cultivadas , Citometria de Fluxo , Expressão Gênica , Inativação Gênica , Humanos , Técnicas In Vitro , Estrutura Molecular , Peptídeos/química , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , Transfecção
18.
Brain Inform ; 3(1): 29-37, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27747597

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, causing changes in memory, thinking, and other dysfunction of brain functions. More and more people are suffering from the disease. Early neuroimaging techniques of AD are needed to develop. This review provides a preliminary summary of the various neuroimaging techniques that have been explored for in vivo imaging of AD. Recent advances in magnetic resonance (MR) techniques, such as functional MR imaging (fMRI) and diffusion MRI, give opportunities to display not only anatomy and atrophy of the medial temporal lobe, but also at microstructural alterations or perfusion disturbance within the AD lesions. Positron emission tomography (PET) imaging has become the subject of intense research for the diagnosis and facilitation of drug development of AD in both animal models and human trials due to its non-invasive and translational characteristic. Fluorodeoxyglucose (FDG) PET and amyloid PET are applied in clinics and research departments. Amyloid beta (Aß) imaging using PET has been recognized as one of the most important methods for the early diagnosis of AD, and numerous candidate compounds have been tested for Aß imaging. Besides in vivo imaging method, a lot of ex vivo modalities are being used in the AD researches. Multiphoton laser scanning microscopy, neuroimaging of metals, and several metal bioimaging methods are also mentioned here. More and more multimodality and multiparametric neuroimaging techniques should improve our understanding of brain function and open new insights into the pathophysiology of AD. We expect exciting results will emerge from new neuroimaging applications that will provide scientific and medical benefits.

19.
PLoS One ; 11(10): e0164762, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27764160

RESUMO

OBJECTIVE: Cerebrospinal fluid (CSF) biomarkers, such as α-synuclein (α-syn), amyloid beta peptide 1-42 (Aß1-42), phosphorylated tau (181P) (p-tau), and total tau (t-tau), have long been associated with the development of Parkinson disease (PD) and other neurodegenerative diseases. In this investigation, we reported the assessment of CSF biomarkers and their correlations with vesicular monoamine transporter 2 (VMAT2) bindings measured with 18F-9-fluoropropyl-(+)-dihydrotetrabenazine (18F-AV133) that is being developed as a biomarker for PD. We test the hypothesis that monoaminergic degeneration was correlated with CSF biomarker levels in untreated PD patients. METHODS: The available online data from the Parkinson's Progression Markers Initiative study (PPMI) project were collected and analyzed, which include demographic information, clinical evaluations, CSF biomarkers (α-syn, Aß1-42, p-tau, and t-tau), 18F-AV133 brain PET, and T1 weighted MRIs. Region of interest (ROI) and voxel-wise Pearson correlation between standardized uptake value ratio (SUVR) and CSF biomarkers were calculated. RESULTS: Our major findings are: 1) Compared with controls, CSF α-syn and tau levels decreased significantly in PD; 2) α-syn was closely correlated with Aß1-42 and tau in PD, especially in early-onset patients; and 3) hypothesis-driven ROI analysis found a significant negative correlation between CSF Aß1-42 levels and VMAT2 densities in post cingulate, left caudate, left anterior putamen, and left ventral striatum in PDs. CSF t-tau and p-tau levels were significantly negatively related to VMAT2 SUVRs in substantia nigra and left ventral striatum, respectively. Voxel-wise analysis showed that left caudate, parahippocampal gyrus, insula and temporal lobe were negatively correlated with Aß1-42. In addition, superior frontal gyrus and transverse temporal gyrus were negatively correlated with CSF p-tau levels. CONCLUSION: These results suggest that monoaminergic degeneration in PD is correlated with CSF biomarkers associated with cognitive impairment in neurodegenerative diseases including Alzheimer's disease. The association between loss of dopamine synaptic function and pathologic protein accumulations in PD indicates an important role of CSF biomarkers in PD development.


Assuntos
Biomarcadores/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Tetrabenazina/análogos & derivados , Proteínas Vesiculares de Transporte de Monoamina/metabolismo , Idoso , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Encéfalo/metabolismo , Feminino , Radioisótopos de Flúor/metabolismo , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/líquido cefalorraquidiano , Doença de Parkinson/metabolismo , Projetos Piloto , Tomografia por Emissão de Pósitrons , Tetrabenazina/metabolismo , alfa-Sinucleína/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano
20.
Neurology ; 87(5): 473-80, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27371485

RESUMO

OBJECTIVE: To evaluate differences in amyloid deposition in a community-based cohort without dementia by age, sex, race, education, and APOE ε4 allele status. METHODS: Recruited from the longitudinal Atherosclerosis Risk in Communities study, 329 participants without dementia, ages 67-88 years, were imaged using florbetapir PET at 3 US community sites (Washington County, Maryland; Forsyth County, North Carolina; and Jackson, Mississippi). Standardized uptake value ratios (SUVRs) were calculated; global cortical SUVR >1.2 was evaluated as the primary outcome. Age, race, sex, education level, and number of APOE ε4 alleles were evaluated in multivariable models including vascular risk factors, brain white matter hyperintensity and total intracranial volume, and cognitive status. RESULTS: A total of 141 of the participants (43%) were black. In multivariable models, odds of elevated SUVR was increased in participants with increasing age (odds ratio [OR] 1.63, 95% confidence interval [CI] 1.01-2.65 per 10 years of age) and black race (OR 2.08, 95% CI 1.23-3.51) but did not differ by educational level. Each ε4 allele was associated with increased odds of elevated SUVR (OR 2.65, 95% CI 1.61-4.39). CONCLUSIONS: In this community-based cohort without dementia, florbetapir uptake is associated with older age and APOE genotype. Black race was associated with higher SUVR, after adjusting for demographics, vascular risk factors, cognitive status, white matter hyperintensity volume, and APOE genotype, with effect sizes nearing those seen for APOE ε4. Replication of these findings is needed in other cohorts, and reasons for and consequences of these observed differences by race warrant further study.


Assuntos
Envelhecimento , Amiloide/metabolismo , Apolipoproteína E4/genética , Encéfalo/metabolismo , Grupos de Populações Continentais , Caracteres Sexuais , Afro-Americanos , Idoso , Idoso de 80 Anos ou mais , Alelos , Compostos de Anilina/metabolismo , Cognição , Escolaridade , Etilenoglicóis/metabolismo , Feminino , Neuroimagem Funcional , Humanos , Masculino , Tomografia por Emissão de Pósitrons , Substância Branca/patologia
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