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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Nanoanalysis
- نوع مقاله: Journal Article
- کلمات کلیدی: Cisplatin,Drug Delivery,Sustained release,Hollow mesoporous silica
- چکیده:
- چکیده انگلیسی: Cisplatin continues to be a first line chemotherapy agent alone or in combination with other cytotoxic agents or
radiotherapy. Dose-limiting side effects, intrinsic and acquired resistance are the main reasons for inventing and developing new ways of delivering cisplatin. Biocompatible hollow porous materials offer high void volume, shell porosity, low density and controllable size which make them promising platforms for efficient drug delivery systems. In this study, hollow mesoporous silica nanoparticles (HMSNs) were successfully synthesized by a hard-templating method. Further, the synthesized HMSNs were studied by characterizing their morphology, nanostructure, specific surface area, particle size distribution and chemical composition using FESEM, HRTEM, N2-Sorption and FTIR techniques, respectively. The high specific surface area (1201 m2g-1) of the prepared HMSNs resulted in relatively high loading capacity of cisplatin (35 wt.%). Furthermore, release test performed at pH value of 7.4 showed a sustained release pattern. The cytotoxicity of the formulated drug was also examined in c26 colon carcinoma cell lines by MTT assay. The drug loaded HMSNs showed a lower toxicity than free drug due to the sustained drug release.- انتشار مقاله: 10-03-1396
- نویسندگان: Zohreh Jomeh Farsangi,Seyed Mehdi Rezayat,Ali Beitollahi,Saeed Sarkar,Mahmoudreza Jaafari,Amir Amani
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: classification,early detection,Melanoma,Elastic Scattering Spectroscopy
- چکیده:
- چکیده انگلیسی: Introduction: There is a strong need for developing clinical technologies and instruments for prompt tissue assessment in a variety of oncological applications as smart methods. Elastic scattering spectroscopy (ESS) is a real-time, noninvasive, point-measurement, optical diagnostic technique for malignancy detection through changes at cellular and subcellular levels, especially important in early diagnosis of invasive skin cancer, melanoma. In fact, this preliminary study was conducted to provide a classification method for analyzing the ESS spectra. Elastic scattering spectra related to the normal skin and melanoma lesions, which were already confirmed pathologically, were provided as input from an ESS database.
Materials and Methods: A program was developed in MATLAB based on singular value decomposition and K-means algorithm for classification.
Results: Accuracy and sensitivity of the proposed classifying method for normal and melanoma spectra were 87.5% and 80%, respectively.
Conclusion: This method can be helpful for classification of melanoma and normal spectra. However, a large body of data and modifications are required to achieve better sensitivity for clinical applications.- انتشار مقاله: 26-10-1395
- نویسندگان: Afshan Shirkavand,Saeed Sarkar,Leila Ataie Fashtami,Hanieh Mohammadreza
- مشاهده
- جایگاه : پژوهشی
- مجله: Asia Oceania Journal of Nuclear Medicine and Biology
- نوع مقاله: Journal Article
- کلمات کلیدی: Image reconstruction,PERSPECT,MLEM,OSEM,ART
- چکیده:
- چکیده انگلیسی: Objective (s): Various iterative reconstruction algorithms in nuclear medicine have been introduced in the last three decades. For each new imaging system, it is wise to select appropriate image reconstruction algorithms and evaluate their performance. In this study, three approaches of image reconstruction were developed for a novel desktop open-gantry SPECT system, PERSPECT, to assess their performance in terms of the quality of the resultant reconstructed images.
Methods: In the present work, a proposed image reconstruction algorithm for the PERSPECT, referred to as quasi-simultaneous multiplicative algebraic reconstruction technique (qSMART), together with two popular image reconstruction methods, maximum-likelihood expectation-maximization (MLEM) and ordered-subsets EM (OSEM), were implemented and compared. Analytic and Monte Carlo simulations were applied for data acquisition of various phantoms including a micro-Derenzo phantom. All acquired data were reconstructed by the three algorithms using different number of iterations (1-40). A thorough set of figures-of-merit was utilized to quantitatively compare the generated images.
Results: OSEM depicted reconstructed images of higher (or matching) quality in comparison to qSMART. MLEM also reached nearly similar quality as OSEM but at higher number of iterations. The graph of data discrepancy revealed that the ranking of the three approaches in terms of convergence speed is as qSMART, OSEM, and MLEM. Furthermore, bias-versus-noise curves indicated that optimal bias-noise results were achieved using OSEM.
Conclusion: The results showed that although qSMART can be applied for image reconstruction if being halted in the early iterations (up to 5), the best achievable quality of images is obtained using the OSEM.- انتشار مقاله: 18-08-1395
- نویسندگان: Navid Zeraatkar,Arman Rahmim,Saeed Sarkar,Mohammad Reza Ay
- مشاهده