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1.
Eur Radiol ; 32(12): 8485-8496, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35699767

RESUMO

OBJECTIVES: To explore the diagnostic performance of EFSUMB CEUS Pancreatic Applications guidelines (version 2017) before and after the addition of iso-enhancement and very fast/fast washout as supplementary diagnostic criteria for PDAC. METHODS: In this retrospective study, patients diagnosed with solid pancreatic lesions from January 2017 to December 2020 were evaluated. Pancreatic ductal adenocarcinoma (PDAC) is reported to show hypo-enhancement in all phases according to the EFSUMB guidelines. First, based on this definition, all lesions were categorized as PDAC and non-PDAC. Then, iso-enhancement and very fast/fast washout were added as supplementary diagnostic criteria, and all lesions were recategorized. The diagnostic performance was assessed in terms of the accuracy (ACC), sensitivity (SEN), specificity (SPE), positive predictive value (PPV), and negative predictive value (NPV). The reference standard consisted of histologic evaluation or composite imaging and clinical follow-up findings. RESULTS: A total of 455 nodules in 450 patients (median age, 58.37 years; 250 men) were included. The diagnostic performance using the EFSUMB CEUS guidelines for PDAC had an ACC of 69.5%, SEN of 65.4%, SPE of 84%, PPV of 93.5%, NPV of 40.6%, and ROC of 0.747. After recategorization according to the supplementary diagnostic criteria, the diagnostic performance for PDAC had an ACC of 95.8%, SEN of 99.2%, SPE of 84%, PPV of 95.7%, NPV of 96.6%, and ROC of 0.916. CONCLUSION: The EFSUMB guidelines and recommendations for pancreatic lesions can effectively identify PDAC via hypo-enhancement on CEUS. However, the diagnostic performance may be further improved by the reclassification of PDAC lesions after adding iso-enhancement and very fast/fast washout mode. KEY POINTS: • In the EFSUMB guidelines, the only diagnostic criterion for PDAC is hypo-enhancement, to which iso-enhancement and very fast/fast washout mode were added in our research. • Using hypo-enhancement/iso-enhancement with very fast/fast washout patterns as the diagnostic criteria for PDAC for solid pancreatic masses on CEUS has high diagnostic accuracy. • The blood supply pattern of PDAC can provide important information, and CEUS has unique advantages in this respect due to its real-time dynamic attenuation ability.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Masculino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Meios de Contraste/farmacologia , Ultrassonografia/métodos , Pâncreas , Neoplasias Pancreáticas/diagnóstico por imagem , Sensibilidade e Especificidade , Diagnóstico Diferencial , Neoplasias Pancreáticas
2.
Environ Res ; 214(Pt 3): 114048, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35961548

RESUMO

Although the contamination of microplastics (MPs) in groundwater has been anticipated, their occurrence, distribution, and composition require further understanding. In this study, the occurrence and distributions of MPs were investigated in shallow groundwater from an important water source district in Tianjin city of northern China. The abundance, the physical morphology, the chemical composition, and the potential correlations of the determined MPs with human activities were thoroughly characterized. MPs were determined from all ten sampling sites with the abundance ranged between 17.0 ± 2.16 to 44.0 ± 1.63 n/L, revealing the ubiquitous existed MPs contamination. Based on the physical categorization, fiber (44.74%) was the most abundant shape, while blue (31.02%) and transparent (26.09%) were the most prevalent colors. The dominant size of MPs was smaller than 200 µm which accounted for 73.10%. A total of seven types of MPs were determined with polyethylene, polyethylene terephthalate, and polystyrene as the main types, of which, polypropylene showed strong positive correlations with polystyrene, indicating the possible similar sources of them. Besides, the determined MPs in groundwater were greater in areas with the high population density and strong population activity, indicating their high correlation with human activity. The study highlighted the presence of MPs in groundwater of drinking water source in northern China and provided useful information for evaluating the potential ecological effects on water quality safety and human health brought by MPs.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , China , Monitoramento Ambiental , Humanos , Microplásticos , Plásticos , Poliestirenos , Poluentes Químicos da Água/análise
3.
J Labelled Comp Radiopharm ; 60(9): 385-393, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28423195

RESUMO

The purpose of our study was to develop and evaluate a novel integrin αv ß3 -specific delivery carrier for transfection of siRNA in malignant tumors. We adopted arginine-glycine-aspartate (RGD) motif as a tissue target for specific recognition of integrin αν ß3 . A chimaeric peptide was synthesized by adding nonamer arginine residues (9-arginine [9R]) at the carboxy terminus of cyclic-RGD dimer, designated as c(RGD)2 -9R, to enable small interfering RNA (siRNA) binding. To test the applicability of the delivery carrier in vivo, c(RGD)2 -9R was labeled with radionuclide of technetium-99m. Biodistribution and γ-camera imaging studies were performed in HepG2 xenograft-bearing nude mice. As results, an optimal 10:1 molar ratio of 99m Tc-c(RGD)2 -9R to siRNA was indicated by the electrophoresis on agarose gels. 99m Tc-c(RGD)2 -9R/siRNA remained stable under a set of conditions in vitro. For in vivo study, tumor radioactivity uptake of 99m Tc-c(RGD)2 -9R/siRNA in nude mice bearing HepG2 xenografts was significantly higher than that of control probe (P < .05). The xenografts were clearly visualized at 4 hours till 6 hours noninvasively after intravenous injection of 99m Tc-c(RGD)2 -9R/siRNA, while the xenografts were not visualized at any time after injection of control probe. It was concluded that c(RGD)2 -9R could be an effective siRNA delivery carrier. Technetium-99m radiolabeled-delivery carrier represents a potential imaging strategy for RNAi-based therapy.


Assuntos
Portadores de Fármacos/química , Neoplasias Hepáticas/patologia , Peptídeos Cíclicos/química , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Transfecção , Animais , Dimerização , Portadores de Fármacos/metabolismo , Portadores de Fármacos/farmacocinética , Feminino , Células Hep G2 , Humanos , Integrina alfaVbeta3/metabolismo , Marcação por Isótopo , Neoplasias Hepáticas/diagnóstico por imagem , Camundongos , Camundongos Nus , Cintilografia , Tecnécio/química , Distribuição Tecidual
4.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(5): 691-4, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-23905393

RESUMO

OBJECTIVE: To observe antisepsis, anti-swelling, and therapeutic effects of Fuxiye (FXY), a Chinese medical lotion for external wash in treating vaginitis model rats. METHODS: The cervicitis rat model was induced by agar plate diffusion, ear auricle swelling induced by dimethylbenzene, and chemical stimulus. The in vitro antibiotic actions of FXY were observed. Besides, its effects on the swelling and inflammation in model rats were also observed. RESULTS: FXY at 25 mg/mL could completely inhibit the growth of Pseudomonas aeruginosa, Escherichia coli, pyogenic Streptococcus, and Streptococcus agalactiae. FXY at 50 mg/mL could completely inhibit the growth of Staphylococcus aureus and Candida albicans. It obviously restrained dimethylbenzene induced ear auricle swelling. It significantly alleviated cervicitis induced by chemical stiumli. CONCLUSION: FXY showed better effects on antisepsis, anti-inflammation, and treating cervicitis.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Cervicite Uterina/tratamento farmacológico , Animais , Anti-Infecciosos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Formas de Dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Ratos , Ratos Sprague-Dawley , Vaginite/tratamento farmacológico
5.
Quant Imaging Med Surg ; 13(6): 3902-3914, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37284072

RESUMO

Background: Contrast-enhanced ultrasound (CEUS) has proven valuable in diagnosing benign and malignant pancreatic diseases, but its value in evaluating hepatic metastasis remains to be further explored. This study investigated the relationship between CEUS features of pancreatic ductal adenocarcinoma (PDAC) and concomitant or recurrent liver metastases after treatment. Methods: This retrospective study included 133 participants with PDAC who were diagnosed with pancreatic lesions with CEUS at Peking Union Medical College Hospital from January 2017 to November 2020. According to the CEUS classification methods in our center, all the pancreatic lesions were classified as either with rich or poor blood supply. Additionally, quantitative ultrasonographic parameters were measured in the center and periphery of all pancreatic lesions. CEUS modes and parameters of the different hepatic metastasis groups were compared. The diagnostic performance of CEUS was calculated for diagnosing synchronous and metachronous hepatic metastasis. Results: The proportions of rich blood supply and poor blood supply were 46% (32/69) and 54% (37/69), respectively, in the no hepatic metastasis group; 42% (14/33) and 58% (19/33), respectively, in the metachronous hepatic metastasis (MHM) group; and 19% (6/31) and 81% (25/31), respectively, in the synchronous hepatic metastasis (SHM) group. The wash-in slope ratio (WIS ratio) between the center of the lesion and around the lesion and peak intensity ratio (PI ratio) between the center of the lesion and around the lesion had higher values in the negative hepatic metastasis group (P<0.05). In predicting synchronous and metachronous hepatic metastasis, the WIS ratio had the best diagnostic performance. The sensitivity (SEN), specificity (SPE), accuracy (ACC), positive predictive value (PPV), and negative predictive value (NPV) were 81.8%, 95.7%, 91.2%, 90.0%, and 91.7%, respectively, for MHM; and 87.1%, 95.7%, 93.0%, 90.0%, and 94.3%, respectively, for SHM. Conclusions: CEUS would be helpful in image surveillance for synchronous or metachronous hepatic metastasis of PDAC.

6.
Curr Med Sci ; 42(5): 1022-1032, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36255661

RESUMO

OBJECTIVE: While the upregulation of cytochrome P450 family 24 subfamily A member 1 (CYP24A1) gene expression has been reported in colon cancer, its role in tumorigenesis remains largely unknown. In this study, we aimed to investigate the involvement of CYP24A1 in Wnt pathway regulation via the nuclear factor kappa B (NF-κB) pathway. METHODS: The human colon cancer cell lines HCT-116 and Caco-2 were subjected to stimulation with interleukin-6 (IL-6) as well as tumor necrosis factor alpha (TNF-α), with subsequent treatment using the NF-κB pathway-specific inhibitor ammonium pyrrolidinedithiocarbamate (PDTC). Furthermore, CYP24A1 expression was subjected to knockdown via the use of small interfering RNA (siRNA). Subsequently, NF-κB pathway activation was determined by an electrophoretic mobility shift assay, and the transcriptional activity of ß-catenin was determined by a dual-luciferase reporter assay. A mouse ulcerative colitis (UC)-associated carcinogenesis model was established, wherein TNF-α and the NF-κB pathway were blocked by anti-TNF-α monoclonal antibody and NF-κB antisense oligonucleotides, respectively. Then the tumor size and protein level of CYP24A1 were determined. RESULTS: IL-6 and TNF-α upregulated CYP24A1 expression and activated the NF-κB pathway in colon cancer cells. PDTC significantly inhibited this increase in CYP24A1 expression. Additionally, knockdown of CYP24A1 expression by siRNA could partially antagonize Wnt pathway activation. Upregulated CYP24A1 expression was observed in the colonic epithelial cells of UC-associated carcinoma mouse models. Anti-TNF-α monoclonal antibody and NF-κB antisense oligonucleotides decreased the tumor size and suppressed CYP24A1 expression. CONCLUSION: Taken together, this study suggests that inflammatory factors may increase CYP24A1 expression via NF-κB pathway activation, which in turn stimulates Wnt signaling.


Assuntos
Compostos de Amônio , Neoplasias do Colo , Camundongos , Animais , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Via de Sinalização Wnt , beta Catenina/genética , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/genética , Vitamina D3 24-Hidroxilase/metabolismo , RNA Interferente Pequeno , Células CACO-2 , Inibidores do Fator de Necrose Tumoral , Proteínas I-kappa B/metabolismo , Neoplasias do Colo/genética , Luciferases/metabolismo , Anticorpos Monoclonais , Oligonucleotídeos Antissenso
7.
Chemosphere ; 295: 133935, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35149011

RESUMO

The co-existence of volatile chlorinated hydrocarbons (VCHs) and nitrate pollution in groundwater is prominent, but how nitrate exposure affects weak-electrical stimulated bio-dechlorination activity of VCH is largely unknown. Here, by establishing weak-electrical stimulated trichloroethylene (TCE) dechlorination systems, the influence on TCE dechlorination by exposure to the different concentrations (25-100 mg L-1) of nitrate was investigated. The existence of nitrate in general decreased TCE dechlorination efficiency to varying degrees, and the higher nitrate concentration, the stronger the inhibitory effects, verified by the gradually decreased transcription levels of tceA. Although the TCE dechlorination kinetic rate constant decreased by 36% the most, under all nitrate concentration ranges, TCE could be completely removed within 32 h and no difference in generated metabolites was found, revealing the well-maintained dechlorination activity. This was due to the quickly enriched bio-denitrification activity, which removed nitrate completely within 9 h, and thus relieved the inhibition on TCE dechlorination. The obvious bacterial community structure succession was also observed, from dominating with dechlorination genera (e.g., Acetobacterium, Eubacterium) to dominating with both dechlorination and denitrification genera (e.g., Acidovorax and Brachymonas). The study proposed the great potential for the in situ simultaneous denitrification and dehalogenation in groundwater contaminated with both nitrate and VCHs.


Assuntos
Água Subterrânea , Hidrocarbonetos Clorados , Tricloroetileno , Biodegradação Ambiental , Estimulação Elétrica , Água Subterrânea/química , Nitratos , Tricloroetileno/química
8.
Nucl Med Commun ; 43(2): 186-192, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34783717

RESUMO

OBJECTIVE: T cell lymphomas are associated with an aggressive worse prognosis. This study is designed to assess T cell lymphomas using 18F-FDG PET/CT. METHODS: Sixty-four patients with newly diagnosed T cell lymphomas underwent PET/computed tomography (PET/CT) scans, 47 cases who were fully followed up were retrospectively reviewed and analyzed. Overall survival (OS) and progression-free survival (PFS) were recorded for prognosis. We measured the maximum standardized uptake value (SUVmax) in all cases, analyzed the correlation between SUVmax and survival and other clinicopathologic parameters. Kaplan-Meier log-rank tests were then used to compare the survival of high and low PET/CT parameter groups, and multivariate Cox proportional hazards regression analysis was carried out to identify predictors of OS and PFS. RESULTS: With a median follow-up of 26.5 (range 0.7-117.5) months, the 1-, 2- and 3-year OS were 75.6, 61.7 and 49.2%, and PFS were 49.3, 39.9 and 29.9%, respectively in 47 patients. Among them, 33 cases progressed with a median time of 9.5 (0.7-115.0) months, and 26 patients died with a median survival time of 26.5 (0.7-117.5) months. Multivariate analysis showed the following independent prognostic factors for OS: age >60 years (P = 0.002), SUVmax >9.7 (P = 0.009) and extranodal involvement of more than one site (P = 0.018). In addition, lactate dehydrogenase level (P = 0.003) and B symptoms (P = 0.018) were independent risk factors for PFS. CONCLUSION: Pretherapy SUVmax may serve as an independent predictor of outcome in patients with newly diagnosed T cell lymphomas.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
9.
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
10.
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 , Povo 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
11.
Int J Clin Exp Med ; 8(2): 1726-36, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25932101

RESUMO

BACKGROUND: To improve the detection of pulmonary metastases, experimental blood-borne pulmonary metastasis mouse models were established using three intravenously administered cell lines. In a previous study we demonstrated that (99m)Tc-radiolabeled arginine-arginine-leucine (RRL) could be used to non-invasively image malignant tumors. METHODS: (99m)Tc-RRL was prepared and injected intravenously in mice with pulmonary metastases that arose from the intravenous injection of HepG2, B16, and Hela cells. The bio-distribution and imaging of (99m)Tc-RRL were determined in different pulmonary metastases mouse models and in normal mice. RESULTS: (99m)Tc-RRL exhibited higher uptake values in the lungs of pulmonary metastatic mice compared to normal mice (P<0.05; 3.92±0.48% ID/g 2 h post-injection and 3.89±0.36% ID/g 4 h post-injection in metastatic hepatic carcinoma [HepG2]-bearing lungs; 5.49±0.84% ID/g 2 h post-injection and 5.11±0.75% ID/g 4 h post-injection in metastatic melanoma [B16]-bearing lungs; 3.72±0.52% ID/g 2 h post-injection and 3.51±0.35% ID/g 4 h post-injection in metastatic cervical carcinoma [Hela]-bearing lungs; 2.38±0.20% ID/g 2 h post-injection and 2.11±0.24% ID/g 4 h post-injection in normal lungs). The pulmonary metastatic lesions were clearly visualized using (99m)Tc-RRL. CONCLUSIONS: (99m)Tc-RRL exhibited favorable metastatic tumor targeting and imaging properties, thus highlighting its potential as an effective imaging probe for detection of pulmonary metastases. (99m)Tc-RRL can be used as a reasonable supplement to (18)F-FDG imaging in the non-invasive imaging of tumor angiogenesis.

12.
Mol Med Rep ; 7(4): 1355-60, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23440460

RESUMO

Tumor angiogenesis is important in the growth and metastasis of malignant tumors. In our previous study, we demonstrated that an arginine-arginine-leucine (RRL) peptide is a tumor endothelial cell-specific binding sequence that may be used as a molecular probe for the imaging of malignant tumors in vivo. The aim of the present study was to further explore the characteristics of 131I­RRL by biodistribution tests, and to estimate the radiation dosimetry of 131I­RRL for humans using mice data. The RRL peptide was radiolabeled with 131I by a chloramine-T (CH-T) method. The radiolabeling efficiency and radiochemical purity were then characterized in vitro. 131I­RRL was injected intravenously into B16 xenograft-bearing Kunming mice. Biodistribution analysis and in vivo imaging were performed periodically. The radiation dosimetry in humans was calculated according to the organ distribution and the standard medical internal radiation dose (MIRD) method in mice. All data were analyzed by statistical and MIRDOSE 3.1 software. The labeling efficiency of 131I­RRL reached 70.0±2.91% (n=5), and the radiochemical purity exceeded 95% following purification. In mice bearing B16 xenografts, 131I­RRL rapidly cleared from the blood and predominantly accumulated in the kidneys, the stomach and the tumor tissue. The specific uptake of 131I­RRL in the tumor increased over time and was significantly higher than that of the other organs, 24-72 h following injection (P<0.05). The ratio of tumor-to-skeletal muscle (T/SM) tissue exceeded 4.75, and the ratio of the tumor-to-blood (T/B) tissue peaked at 3.36. In the single-photon emission computed tomography (SPECT) imaging of Kunming mice bearing B16 xenografts, the tumors were clearly identifiable at 6 h, and significant uptake was evident 24-72 h following administration of 131I­RRL. The effective dose for the adult male dosimetric model was estimated to be 0.0293 mSv/MBq. Higher absorbed doses were estimated for the stomach (0.102 mGy/MBq), the small intestines (0.0699 mGy/MBq), the kidneys (0.0611 mGy/MBq) and the liver (0.055 mGy/MBq). These results highlight the potential of 131I­RRL as a ligand for the SPECT imaging of tumors. Administration of 131I­RRL led to a reasonable radiation dose burden and was safe for human use.


Assuntos
Melanoma Experimental/diagnóstico , Sondas Moleculares , Neovascularização Patológica/diagnóstico , Peptídeos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Animais , Arginina/química , Humanos , Leucina/química , Melanoma Experimental/patologia , Camundongos , Neovascularização Patológica/complicações , Neovascularização Patológica/patologia , Peptídeos/química , Doses de Radiação , Distribuição Tecidual
13.
PLoS One ; 8(7): e70188, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23936161

RESUMO

OBJECTIVE: The α7 nicotinic acetylcholine receptors (nAChRs) play a vital role in the pathophysiology of neuropsychiatric diseases such as Alzheimer's disease and depression. However, there is currently no suitable positron emission tomography (PET) or Single-Photon Emission Computed Tomography (SPECT) radioligands for imaging α7 nAChRs in brain. Here our aim is to radiosynthesize a novel SPECT radioligand (131)I-CHIBA-1001 for whole body biodistribution study and in vivo imaging of α7 nAChRs in brain. METHOD: (131)I-CHIBA-1001 was radiosynthesized by chloramine-T method. Different conditions of reaction time and temperature were tested to get a better radiolabeling yield. Radiolabeling yield and radiochemical purities of (131)I-CHIBA-1001 were analyzed by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) system. Whole body biodistribution study was performed at different time points post injection of (131)I-CHIBA-1001 in KM mice. Monkey subject was used for in vivo SPECT imaging in brain. RESULT: The radiolabeling yield of (131)I-CHIBA-1001 reached 96% within 1.5∼2.0 h at 90∼95°C. The radiochemical purity reached more than 99% after HPLC purification. (131)I-CHIBA-1001 was highly stable in saline and fresh human serum in room temperature and 37°C separately. The biodistribution data of brain at 15, 30, and 60 min were 11.05±1.04%ID/g, 8.8±0.04%ID/g and 6.28±1.13%ID/g, respectively. In experimental SPECT imaging, the distribution of radioactivity in the brain regions was paralleled with the distribution of α7 nAChRs in the monkey brain. Moreover, in the blocking SPECT imaging study, the selective α7 nAChR agonist SSR180711 blocked the radioactive uptake in the brain successfully. CONCLUSION: The CHIBA-1001 can be successfully radiolabeled with (131)I using the chloramine-T method. (131)I-CHIBA-1001 can successfully accumulate in the monkey brain and image the α7 acetylcholine receptors. (131)I-CHIBA-1001 can be a candidate for imagingα7 acetylcholine receptors, which will be of great value for the diagnosis and treatment of mental diseases.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/metabolismo , Radioisótopos do Iodo/química , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Haplorrinos , Humanos , Ligantes , Masculino , Camundongos , Tomografia por Emissão de Pósitrons , Ligação Proteica , Ratos , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único
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