Publications by authors named "Mojtaba Hoseini-Ghahfarokhi"

13 Publications

  • Page 1 of 1

Applications of Graphene and Graphene Oxide in Smart Drug/Gene Delivery: Is the World Still Flat?

Int J Nanomedicine 2020 27;15:9469-9496. Epub 2020 Nov 27.

Iran Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran.

Graphene, a wonder material, has made far-reaching developments in many different fields such as materials science, electronics, condensed physics, quantum physics, energy systems, etc. Since its discovery in 2004, extensive studies have been done for understanding its physical and chemical properties. Owing to its unique characteristics, it has rapidly became a potential candidate for nano-bio researchers to explore its usage in biomedical applications. In the last decade, remarkable efforts have been devoted to investigating the biomedical utilization of graphene and graphene-based materials, especially in smart drug and gene delivery as well as cancer therapy. Inspired by a great number of successful graphene-based materials integrations into the biomedical area, here we summarize the most recent developments made about graphene applications in biomedicine. In this paper, we review the up-to-date advances of graphene-based materials in drug delivery applications, specifically targeted drug/ gene delivery, delivery of antitumor drugs, controlled and stimuli-responsive drug release, photodynamic therapy applications and optical imaging and theranostics, as well as investigating the future trends and succeeding challenges in this topic to provide an outlook for future researches.
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http://dx.doi.org/10.2147/IJN.S265876DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7710865PMC
December 2020

A Review on the Biodistribution, Pharmacokinetics and Toxicity of Bismuth-Based Nanomaterials.

Int J Nanomedicine 2020 25;15:7079-7096. Epub 2020 Sep 25.

Marquette University School of Dentistry, Milwaukee, WI 53233, USA.

Here, bismuth-based nanomaterials (Bi-based NMs) are introduced as promising theranostic agents to enhance image contrast as well as for the therapeutic gain for numerous diseases. However, understanding the interaction of such novel developed nanoparticles (NPs) within a biological environment is a requisite for the translation of any promising agent from the lab bench to the clinic. This interaction delineates the fate of NPs after circulation in the body. In an ideal setting, a nano-based therapeutic agent should be eliminated via the renal clearance pathway, meanwhile it should have specific targeting to a diseased organ to reach an effective dose and also to overcome off-targeting. Due to their clearance pathway, biodistribution patterns and pharmacokinetics (PK), Bi-based NMs have been found to play a determinative role to pass clinical approval and they have been investigated extensively in vivo to date. In this review, we expansively discuss the possible toxicity induced by Bi-based NMs on cells or organs, as well as biodistribution profiles, PK and the clearance pathways in animal models. A low cytotoxicity of Bi-based NMs has been found in vitro and in vivo, and along with their long-term biodistribution and proper renal clearance in animal models, the translation of Bi-based NMs to the clinic as a useful novel theranostic agent is promising to improve numerous medical applications.
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http://dx.doi.org/10.2147/IJN.S250001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7526011PMC
December 2020

Iron oxide/gold nanoparticles-decorated reduced graphene oxide nanohybrid as the thermo-radiotherapy agent.

IET Nanobiotechnol 2020 Jul;14(5):428-432

Department of Immunology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.

The main focus of the current study is the fabrication of a multifunctional nanohybrid based on graphene oxide (GO)/iron oxide/gold nanoparticles (NPs) as the combinatorial cancer treatment agent. Gold and iron oxide NPs formed on the GONPs via the in situ synthesis approach. The characterisations showed that gold and iron oxide NPs formed onto the GO. Cell toxicity assessment revealed that the fabricated nanohybrid exhibited negligible toxicity against MCF-7 cells in low doses (<50 ppm). Temperature measurement showed a time and dose-dependent heat elevation under the interaction of the nanohybrid with the radio frequency (RF) wave. The highest temperature was recorded using 200 ppm concentration nanohybrid during 40 min exposure. The combinatorial treatments demonstrated that the maximum cell death (average of 53%) was induced with the combination of the nanohybrid with RF waves and radiotherapy (RT). The mechanistic study using the flow cytometry technique illustrated that early apoptosis was the main underlying cell death. Moreover, the dose enhancement factor of 1.63 and 2.63 were obtained from RT and RF, respectively. To sum up, the authors' findings indicated that the prepared nanohybrid could be considered as multifunctional and combinatorial cancer therapy agents.
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http://dx.doi.org/10.1049/iet-nbt.2020.0106DOI Listing
July 2020

Targeting of cellular redox metabolism for mitigation of radiation injury.

Life Sci 2020 Jun 20;250:117570. Epub 2020 Mar 20.

Radiology and Nuclear Medicine Department, School of Paramedical Sciences, Kermanshah University of Medical Sciences, Kermanshah, Iran. Electronic address:

Accidental exposure to ionizing radiation is a serious concern to human life. Studies on the mitigation of side effects following exposure to accidental radiation events are ongoing. Recent studies have shown that radiation can activate several signaling pathways, leading to changes in the metabolism of free radicals including reactive oxygen species (ROS) and nitric oxide (NO). Cellular and molecular mechanisms show that radiation can cause disruption of normal reduction/oxidation (redox) system. Mitochondria malfunction following exposure to radiation and mutations in mitochondria DNA (mtDNA) have a key role in chronic oxidative stress. Furthermore, exposure to radiation leads to infiltration of inflammatory cells such as macrophages, lymphocytes and mast cells, which are important sources of ROS and NO. These cells generate free radicals via upregulation of some pro-oxidant enzymes such as NADPH oxidases, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Epigenetic changes also have a key role in a similar way. Other mediators such as mammalian target of rapamycin (mTOR) and peroxisome proliferator-activated receptor (PPAR), which are involved in the normal metabolism of cells have also been shown to regulate cell death following exposure to radiation. These mechanisms are tissue specific. Inhibition or activation of each of these targets can be suggested for mitigation of radiation injury in a specific tissue. In the current paper, we review the cellular and molecular changes in the metabolism of cells and ROS/NO following exposure to radiation. Furthermore, the possible strategies for mitigation of radiation injury through modulation of cellular metabolism in irradiated organs will be discussed.
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http://dx.doi.org/10.1016/j.lfs.2020.117570DOI Listing
June 2020

TGF-β in radiotherapy: Mechanisms of tumor resistance and normal tissues injury.

Pharmacol Res 2020 05 4;155:104745. Epub 2020 Mar 4.

Radiology and Nuclear Medicine Department, School of Paramedical Sciences, Kermanshah University of Medical Sciences, Kermanshah, Iran. Electronic address:

Emerging evidences show that changes in tumor stroma can adapt cancer cells to radiotherapy, thereby leading to a reduction in tumor response to treatment. On the other hand, radiotherapy is associated with severe reactions in normal tissues which limit the amount radiation dose received by tumor. These challenges open a window in radiobiology and radiation oncology to explore mechanisms for improving tumor response and also alleviate side effects of radiotherapy. Transforming growth factor beta (TGF-β) is a well-known and multitasking cytokine that regulates a wide range of reactions and interactions within tumor and normal tissues. Within tumor microenvironment (TME), TGF-β is the most potent suppressor of immune system activity against cancer cells. This effect is mediated through stimulation of CD4+ which differentiates to T regulatory cells (Tregs), infiltration of fibroblasts and differentiation into cancer associated fibroblasts (CAFs), and also polarization of macrophages to M2 cells. These changes lead to suppression of cytotoxic CD8 + T lymphocytes (CTLs) and natural killer (NK) cells to kill cancer cells. TGF-β also plays a key role in the angiogenesis, invasion and DNA damage responses (DDR) in cancer cells. In normal tissues, TGF-β triggers the expression of a wide range of pro-oxidant and pro-fibrosis genes, leading to fibrosis, genomic instability and some other side effects. These properties of TGF-β make it a potential target to preserve normal tissues and sensitize tumor via its inhibition. In the current review, we aim to explain the mechanisms of upregulation of TGF-β and its consequences in both tumor and normal tissues.
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http://dx.doi.org/10.1016/j.phrs.2020.104745DOI Listing
May 2020

Bismuth-Based Nanomaterials: Recent Advances in Tumor Targeting and Synergistic Cancer Therapy Techniques.

Adv Healthc Mater 2020 04 6;9(7):e1901695. Epub 2020 Mar 6.

School of Dentistry, Marquette University, Milwaukee, WI, 53233, USA.

Despite all of the efforts in the field of cancer therapy, the heterogeneous properties of tumor cells induce an insufficient therapeutic outcome when treated with conventional monotherapies, necessitating a shift in cancer treatment from monotherapy to combination therapy for complete cancer treatment. Multifunctional bismuth (Bi)-based nanomaterials (NMs) with therapeutic functions hold great promise for the fields of cancer diagnosis and therapy based on their low toxicity, X-ray sensitive capabilities, high atomic number, near-infrared driven semiconductor properties, and low cost. Herein, a comprehensive review of recent advances in various medicinal aspects of Bi-based NMs is presented including: evaluation of in-tumor site accumulation, tumor targeting, and therapeutic performance, as well as the characteristics, benefits, and shortcomings of Bi-based NM-mediated major monotherapies. In addition, the cooperative enhancement mechanisms between two or more of these monotherapies are described in detail to address common challenges in cancer therapy, such as multidrug resistance, hypoxia, and metastasis. Finally, this review opens new insights into the design of multimodal synergistic therapies for potential future clinical applications of Bi-based NMs.
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http://dx.doi.org/10.1002/adhm.201901695DOI Listing
April 2020

Targets for protection and mitigation of radiation injury.

Cell Mol Life Sci 2020 Aug 18;77(16):3129-3159. Epub 2020 Feb 18.

Department of Medical Physics and Radiology, Faculty of Paramedical Sciences, Kashan University of Medical Sciences, Kashan, Iran.

Protection of normal tissues against toxic effects of ionizing radiation is a critical issue in clinical and environmental radiobiology. Investigations in recent decades have suggested potential targets that are involved in the protection against radiation-induced damages to normal tissues and can be proposed for mitigation of radiation injury. Emerging evidences have been shown to be in contrast to an old dogma in radiation biology; a major amount of reactive oxygen species (ROS) production and cell toxicity occur during some hours to years after exposure to ionizing radiation. This can be attributed to upregulation of inflammatory and fibrosis mediators, epigenetic changes and disruption of the normal metabolism of oxygen. In the current review, we explain the cellular and molecular changes following exposure of normal tissues to ionizing radiation. Furthermore, we review potential targets that can be proposed for protection and mitigation of radiation toxicity.
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http://dx.doi.org/10.1007/s00018-020-03479-xDOI Listing
August 2020

Mapping 123 million neonatal, infant and child deaths between 2000 and 2017.

Authors:
Roy Burstein Nathaniel J Henry Michael L Collison Laurie B Marczak Amber Sligar Stefanie Watson Neal Marquez Mahdieh Abbasalizad-Farhangi Masoumeh Abbasi Foad Abd-Allah Amir Abdoli Mohammad Abdollahi Ibrahim Abdollahpour Rizwan Suliankatchi Abdulkader Michael R M Abrigo Dilaram Acharya Oladimeji M Adebayo Victor Adekanmbi Davoud Adham Mahdi Afshari Mohammad Aghaali Keivan Ahmadi Mehdi Ahmadi Ehsan Ahmadpour Rushdia Ahmed Chalachew Genet Akal Joshua O Akinyemi Fares Alahdab Noore Alam Genet Melak Alamene Kefyalew Addis Alene Mehran Alijanzadeh Cyrus Alinia Vahid Alipour Syed Mohamed Aljunid Mohammed J Almalki Hesham M Al-Mekhlafi Khalid Altirkawi Nelson Alvis-Guzman Adeladza Kofi Amegah Saeed Amini Arianna Maever Loreche Amit Zohreh Anbari Sofia Androudi Mina Anjomshoa Fereshteh Ansari Carl Abelardo T Antonio Jalal Arabloo Zohreh Arefi Olatunde Aremu Bahram Armoon Amit Arora Al Artaman Anvar Asadi Mehran Asadi-Aliabadi Amir Ashraf-Ganjouei Reza Assadi Bahar Ataeinia Sachin R Atre Beatriz Paulina Ayala Quintanilla Martin Amogre Ayanore Samad Azari Ebrahim Babaee Arefeh Babazadeh Alaa Badawi Soghra Bagheri Mojtaba Bagherzadeh Nafiseh Baheiraei Abbas Balouchi Aleksandra Barac Quique Bassat Bernhard T Baune Mohsen Bayati Neeraj Bedi Ettore Beghi Masoud Behzadifar Meysam Behzadifar Yared Belete Belay Brent Bell Michelle L Bell Dessalegn Ajema Berbada Robert S Bernstein Natalia V Bhattacharjee Suraj Bhattarai Zulfiqar A Bhutta Ali Bijani Somayeh Bohlouli Nicholas J K Breitborde Gabrielle Britton Annie J Browne Sharath Burugina Nagaraja Reinhard Busse Zahid A Butt Josip Car Rosario Cárdenas Carlos A Castañeda-Orjuela Ester Cerin Wagaye Fentahun Chanie Pranab Chatterjee Dinh-Toi Chu Cyrus Cooper Vera M Costa Koustuv Dalal Lalit Dandona Rakhi Dandona Farah Daoud Ahmad Daryani Rajat Das Gupta Ian Davis Nicole Davis Weaver Dragos Virgil Davitoiu Jan-Walter De Neve Feleke Mekonnen Demeke Gebre Teklemariam Demoz Kebede Deribe Rupak Desai Aniruddha Deshpande Hanna Demelash Desyibelew Sagnik Dey Samath Dhamminda Dharmaratne Meghnath Dhimal Daniel Diaz Leila Doshmangir Andre R Duraes Laura Dwyer-Lindgren Lucas Earl Roya Ebrahimi Soheil Ebrahimpour Andem Effiong Aziz Eftekhari Elham Ehsani-Chimeh Iman El Sayed Maysaa El Sayed Zaki Maha El Tantawi Ziad El-Khatib Mohammad Hassan Emamian Shymaa Enany Sharareh Eskandarieh Oghenowede Eyawo Maha Ezalarab Mahbobeh Faramarzi Mohammad Fareed Roghiyeh Faridnia Andre Faro Ali Akbar Fazaeli Mehdi Fazlzadeh Netsanet Fentahun Seyed-Mohammad Fereshtehnejad João C Fernandes Irina Filip Florian Fischer Nataliya A Foigt Masoud Foroutan Joel Msafiri Francis Takeshi Fukumoto Nancy Fullman Silvano Gallus Destallem Gebremedhin Gebre Tsegaye Tewelde Gebrehiwot Gebreamlak Gebremedhn Gebremeskel Bradford D Gessner Birhanu Geta Peter W Gething Reza Ghadimi Keyghobad Ghadiri Mahsa Ghajarzadeh Ahmad Ghashghaee Paramjit Singh Gill Tiffany K Gill Nick Golding Nelson G M Gomes Philimon N Gona Sameer Vali Gopalani Giuseppe Gorini Bárbara Niegia Garcia Goulart Nicholas Graetz Felix Greaves Manfred S Green Yuming Guo Arvin Haj-Mirzaian Arya Haj-Mirzaian Brian James Hall Samer Hamidi Hamidreza Haririan Josep Maria Haro Milad Hasankhani Edris Hasanpoor Amir Hasanzadeh Hadi Hassankhani Hamid Yimam Hassen Mohamed I Hegazy Delia Hendrie Fatemeh Heydarpour Thomas R Hird Chi Linh Hoang Gillian Hollerich Enayatollah Homaie Rad Mojtaba Hoseini-Ghahfarokhi Naznin Hossain Mostafa Hosseini Mehdi Hosseinzadeh Mihaela Hostiuc Sorin Hostiuc Mowafa Househ Mohamed Hsairi Olayinka Stephen Ilesanmi Mohammad Hasan Imani-Nasab Usman Iqbal Seyed Sina Naghibi Irvani Nazrul Islam Sheikh Mohammed Shariful Islam Mikk Jürisson Nader Jafari Balalami Amir Jalali Javad Javidnia Achala Upendra Jayatilleke Ensiyeh Jenabi John S Ji Yash B Jobanputra Kimberly Johnson Jost B Jonas Zahra Jorjoran Shushtari Jacek Jerzy Jozwiak Ali Kabir Amaha Kahsay Hamed Kalani Rohollah Kalhor Manoochehr Karami Surendra Karki Amir Kasaeian Nicholas J Kassebaum Peter Njenga Keiyoro Grant Rodgers Kemp Roghayeh Khabiri Yousef Saleh Khader Morteza Abdullatif Khafaie Ejaz Ahmad Khan Junaid Khan Muhammad Shahzeb Khan Young-Ho Khang Khaled Khatab Amir Khater Mona M Khater Alireza Khatony Mohammad Khazaei Salman Khazaei Maryam Khazaei-Pool Jagdish Khubchandani Neda Kianipour Yun Jin Kim Ruth W Kimokoti Damaris K Kinyoki Adnan Kisa Sezer Kisa Tufa Kolola Soewarta Kosen Parvaiz A Koul Ai Koyanagi Moritz U G Kraemer Kewal Krishan Kris J Krohn Nuworza Kugbey G Anil Kumar Manasi Kumar Pushpendra Kumar Desmond Kuupiel Ben Lacey Sheetal D Lad Faris Hasan Lami Anders O Larsson Paul H Lee Mostafa Leili Aubrey J Levine Shanshan Li Lee-Ling Lim Stefan Listl Joshua Longbottom Jaifred Christian F Lopez Stefan Lorkowski Sameh Magdeldin Hassan Magdy Abd El Razek Muhammed Magdy Abd El Razek Azeem Majeed Afshin Maleki Reza Malekzadeh Deborah Carvalho Malta Abdullah A Mamun Navid Manafi Ana-Laura Manda Morteza Mansourian Francisco Rogerlândio Martins-Melo Anthony Masaka Benjamin Ballard Massenburg Pallab K Maulik Benjamin K Mayala Mohsen Mazidi Martin McKee Ravi Mehrotra Kala M Mehta Gebrekiros Gebremichael Meles Walter Mendoza Ritesh G Menezes Atte Meretoja Tuomo J Meretoja Tomislav Mestrovic Ted R Miller Molly K Miller-Petrie Edward J Mills George J Milne G K Mini Seyed Mostafa Mir Hamed Mirjalali Erkin M Mirrakhimov Efat Mohamadi Dara K Mohammad Aso Mohammad Darwesh Naser Mohammad Gholi Mezerji Ammas Siraj Mohammed Shafiu Mohammed Ali H Mokdad Mariam Molokhia Lorenzo Monasta Yoshan Moodley Mahmood Moosazadeh Ghobad Moradi Masoud Moradi Yousef Moradi Maziar Moradi-Lakeh Mehdi Moradinazar Paula Moraga Lidia Morawska Abbas Mosapour Seyyed Meysam Mousavi Ulrich Otto Mueller Atalay Goshu Muluneh Ghulam Mustafa Behnam Nabavizadeh Mehdi Naderi Ahamarshan Jayaraman Nagarajan Azin Nahvijou Farid Najafi Vinay Nangia Duduzile Edith Ndwandwe Nahid Neamati Ionut Negoi Ruxandra Irina Negoi Josephine W Ngunjiri Huong Lan Thi Nguyen Long Hoang Nguyen Son Hoang Nguyen Katie R Nielsen Dina Nur Anggraini Ningrum Yirga Legesse Nirayo Molly R Nixon Chukwudi A Nnaji Marzieh Nojomi Mehdi Noroozi Shirin Nosratnejad Jean Jacques Noubiap Soraya Nouraei Motlagh Richard Ofori-Asenso Felix Akpojene Ogbo Kelechi E Oladimeji Andrew T Olagunju Meysam Olfatifar Solomon Olum Bolajoko Olubukunola Olusanya Mojisola Morenike Oluwasanu Obinna E Onwujekwe Eyal Oren Doris D V Ortega-Altamirano Alberto Ortiz Osayomwanbo Osarenotor Frank B Osei Aaron E Osgood-Zimmerman Stanislav S Otstavnov Mayowa Ojo Owolabi Mahesh P A Abdol Sattar Pagheh Smita Pakhale Songhomitra Panda-Jonas Animika Pandey Eun-Kee Park Hadi Parsian Tahereh Pashaei Sangram Kishor Patel Veincent Christian Filipino Pepito Alexandre Pereira Samantha Perkins Brandon V Pickering Thomas Pilgrim Majid Pirestani Bakhtiar Piroozi Meghdad Pirsaheb Oleguer Plana-Ripoll Hadi Pourjafar Parul Puri Mostafa Qorbani Hedley Quintana Mohammad Rabiee Navid Rabiee Amir Radfar Alireza Rafiei Fakher Rahim Zohreh Rahimi Vafa Rahimi-Movaghar Shadi Rahimzadeh Fatemeh Rajati Sree Bhushan Raju Azra Ramezankhani Chhabi Lal Ranabhat Davide Rasella Vahid Rashedi Lal Rawal Robert C Reiner Andre M N Renzaho Satar Rezaei Aziz Rezapour Seyed Mohammad Riahi Ana Isabel Ribeiro Leonardo Roever Elias Merdassa Roro Max Roser Gholamreza Roshandel Daem Roshani Ali Rostami Enrico Rubagotti Salvatore Rubino Siamak Sabour Nafis Sadat Ehsan Sadeghi Reza Saeedi Yahya Safari Roya Safari-Faramani Mahdi Safdarian Amirhossein Sahebkar Mohammad Reza Salahshoor Nasir Salam Payman Salamati Farkhonde Salehi Saleh Salehi Zahabi Yahya Salimi Hamideh Salimzadeh Joshua A Salomon Evanson Zondani Sambala Abdallah M Samy Milena M Santric Milicevic Bruno Piassi Sao Jose Sivan Yegnanarayana Iyer Saraswathy Rodrigo Sarmiento-Suárez Benn Sartorius Brijesh Sathian Sonia Saxena Alyssa N Sbarra Lauren E Schaeffer David C Schwebel Sadaf G Sepanlou Seyedmojtaba Seyedmousavi Faramarz Shaahmadi Masood Ali Shaikh Mehran Shams-Beyranvand Amir Shamshirian Morteza Shamsizadeh Kiomars Sharafi Mehdi Sharif Mahdi Sharif-Alhoseini Hamid Sharifi Jayendra Sharma Rajesh Sharma Aziz Sheikh Chloe Shields Mika Shigematsu Rahman Shiri Ivy Shiue Kerem Shuval Tariq J Siddiqi João Pedro Silva Jasvinder A Singh Dhirendra Narain Sinha Malede Mequanent Sisay Solomon Sisay Karen Sliwa David L Smith Ranjani Somayaji Moslem Soofi Joan B Soriano Chandrashekhar T Sreeramareddy Agus Sudaryanto Mu'awiyyah Babale Sufiyan Bryan L Sykes P N Sylaja Rafael Tabarés-Seisdedos Karen M Tabb Takahiro Tabuchi Nuno Taveira Mohamad-Hani Temsah Abdullah Sulieman Terkawi Zemenu Tadesse Tessema Kavumpurathu Raman Thankappan Sathish Thirunavukkarasu Quyen G To Marcos Roberto Tovani-Palone Bach Xuan Tran Khanh Bao Tran Irfan Ullah Muhammad Shariq Usman Olalekan A Uthman Amir Vahedian-Azimi Pascual R Valdez Job F M van Boven Tommi Juhani Vasankari Yasser Vasseghian Yousef Veisani Narayanaswamy Venketasubramanian Francesco S Violante Sergey Konstantinovitch Vladimirov Vasily Vlassov Theo Vos Giang Thu Vu Isidora S Vujcic Yasir Waheed Jon Wakefield Haidong Wang Yafeng Wang Yuan-Pang Wang Joseph L Ward Robert G Weintraub Kidu Gidey Weldegwergs Girmay Teklay Weldesamuel Ronny Westerman Charles Shey Wiysonge Dawit Zewdu Wondafrash Lauren Woyczynski Ai-Min Wu Gelin Xu Abbas Yadegar Tomohide Yamada Vahid Yazdi-Feyzabadi Christopher Sabo Yilgwan Paul Yip Naohiro Yonemoto Javad Yoosefi Lebni Mustafa Z Younis Mahmoud Yousefifard Hebat-Allah Salah A Yousof Chuanhua Yu Hasan Yusefzadeh Erfan Zabeh Telma Zahirian Moghadam Sojib Bin Zaman Mohammad Zamani Hamed Zandian Alireza Zangeneh Taddese Alemu Zerfu Yunquan Zhang Arash Ziapour Sanjay Zodpey Christopher J L Murray Simon I Hay

Nature 2019 10 16;574(7778):353-358. Epub 2019 Oct 16.

Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA.

Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2-to end preventable child deaths by 2030-we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000-2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations.
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http://dx.doi.org/10.1038/s41586-019-1545-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6800389PMC
October 2019

A new approach to automatic fetal brain extraction from MRI using a variational level set method.

Med Phys 2019 Nov 12;46(11):4983-4991. Epub 2019 Sep 12.

Department of Radiation Oncology and Radiology, University of Mississippi Medical Center (UMMC), Jackson, MS, USA.

Background And Purpose: Appropriate images extracted from the MRI of mothers' wombs can be of great help in the medical diagnosis of fetal abnormalities. As maternal tissue may appear in such images, affecting visualization of myelination of the fetal brain, it is not possible to use methods routinely used for extraction of adult brains for fetal brains. The aim of the present study was to use a variational level set approach to extract fetal brain from T2-weighted MR images of the womb.

Methods: Coronal T2-weighted images were acquired using fast MRI protocols (to avoid artifacts). The database includes 105 MR images from eight subjects. After correcting the inhomogeneity of the images, the fetal eyes were located, and from that information, the location of the fetus brain was automatically determined. Then, the variational level set was used for fetus brain extraction. The results were analyzed by a clinical specialist (radiologist) and the similarity (Dice and Jaccard coefficients), sensitivity and specificity were calculated.

Results And Conclusions: The means of the statistical analysis for the Dice and Jaccard coefficients, sensitivity and specificity, were 99.56%, 96.89%, 95.71%, and 97.96%, respectively. Thus, extraction of fetal brain from MR images was confirmed, both statistically and visually through cross-validation.
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http://dx.doi.org/10.1002/mp.13766DOI Listing
November 2019

Improvement of dose distribution in ocular brachytherapy with I seeds 20-mm COMS plaque followed to loading of choroidal tumor by gold nanoparticles.

J Cancer Res Ther 2019 Jul-Sep;15(3):504-511

Department of Radiology and Nuclear Medicine, School of Para Medical Sciences, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Aims And Objectives: Brachytherapy using removable ophthalmic plaques loaded with suitable small sealed radioactive seeds adjacent to the ocular's tumor has been widely used as an effective treatment. The aim of this study was to investigate the dose distribution in a modeled eyeball followed to loading of an ocular melanoma tumor with different concentrations of gold nanoparticles (GNPs) as dose enhancement agent by Monte Carlo (MC) calculations.

Materials And Methods: The MC code of MCNPX 2.6.0 was used to modeling of COMS standard eye plaque loaded with 24 I sources (6711 model) located on the sclera of modeled eyeball with detailed structures and materials. A choroidal melanoma tumor was simulated and loaded with different concentrations of spherical gold GNPs (50 nm in diameter). Dose enhancement factors (DEFs) of ocular components were calculated.

Results: The dosimetric properties of I source (6711 model) and dose distribution of COMS standard eye plaque were calculated successfully as recommended by TG-43U1; AAPM. Loading of tumor with GNPs increased dose to the tumor and decreased dose to the normal tissues; the DEF was increased up to 2.280 and 2.030 for tumor apex, while it was decreased to 0.760 and 0.892 for macula and for gold-tumor mixture and nanolattice distributions, respectively.

Conclusion: Loading the choroidal tumor volume with GNPs improves the dose distribution by increasing dose to the tumor and decreasing dose to the health components in ocular brachytherapy with I seeds 20-mm COMS plaque.
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http://dx.doi.org/10.4103/jcrt.JCRT_907_17DOI Listing
November 2019

Assessment of two hemispherical and hemispherical-conical miniature sources used in electronic brachytherapy using Monte Carlo Simulation.

Electron Physician 2017 Feb 25;9(2):3845-3856. Epub 2017 Feb 25.

Ph.D. of Medical Physics, Assistant Professor, Department of Para Medicine, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

Introduction: Since the heart of the electronic brachytherapy system is a tube of a miniature x-ray and due to the increasing use of electronic brachytherapy, there is an urgent need for acquiring knowledge about the X-ray spectrum produced, and distribution of x-ray dose. This study aimed to assess the optimal target thickness (TT), the X-ray source spectrum, and the absorbed dose of two miniature sources of hemispherical and hemispherical-conical used in electronic brachytherapy systems, through a Monte Carlo simulation.

Methods: Considering the advantages of MCNPX Code (2.6.0), two input files corresponding to the characteristics of the investigated miniature sources were prepared for this code and then were used for simulation. The optimal thickness (OT) of gold and tungsten targets was determined for the energy levels of 40, 45, and 50 kilo-electron-volts.

Results: In this study, the values of the size of the optimal thickness of 0.92, 1.01 and 1.06 μ for gold target and values of 0.99, 1.08 and 1.34 μ for tungsten target were obtained for energies 40, 45 and 50 keV that using these values, the optimum thickness of 0.92, X-ray spectrum within and outside targets, axial and radial doses for the used energy were calculated for two miniature sources.

Conclusion: It was found that the energy of incident electron, target shape, cross-sectional area of the produced bremsstrahlung, atomic number of materials constituting of the target and output window are the factors with the greatest impacts on the produced X-ray spectrum and the absorbed dose.
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http://dx.doi.org/10.19082/3845DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5410916PMC
February 2017

Dosimetric Characteristics of 6 MV Modified Beams by Physical Wedges of a Siemens Linear Accelerator.

Asian Pac J Cancer Prev 2016 ;17(4):1685-9

Department of Medical Physics, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran E-mail :

Physical wedges still can be used as missing tissue compensators or filters to alter the shape of isodose curves in a target volume to reach an optimal radiotherapy plan without creating a hotspot. The aim of this study was to investigate the dosimetric properties of physical wedges filters such as off-axis photon fluence, photon spectrum, output factor and half value layer. The photon beam quality of a 6 MV Primus Siemens modified by 150 and 450 physical wedges was studied with BEAMnrc Monte Carlo (MC) code. The calculated present depth dose and dose profile curves for open and wedged photon beam were in good agreement with the measurements. Increase of wedge angle increased the beam hardening and this effect was more pronounced at the heal region. Using such an accurate MC model to determine of wedge factors and implementation of it as a calculation algorithm in the future treatment planning systems is recommended.
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http://dx.doi.org/10.7314/apjcp.2016.17.4.1685DOI Listing
January 2017

Determination of Initial Beam Parameters of Varian 2100 CD Linac for Various Therapeutic Electrons Using PRIMO.

Asian Pac J Cancer Prev 2015 ;16(17):7795-801

Student Research Committee, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran E-mail :

The aim of the present research was to establish primary characteristics of electron beams for a Varian 2100C/D linear accelerator with recently developed PRIMO Monte Carlo software and to verify relations between electron energy and dose distribution. To maintain conformity of simulated and measured dose curves within 1%/1mm, mean energy, Full Width at Half Maximum (FWHM) of energy and focal spot FWHM of initial beam were changed iteratively. Mean and most probable energies were extracted from validated phase spaces and compared with related empirical equation results. To explain the importance of correct estimation of primary energy on a clinical case, computed tomography images of a thorax phantom were imported in PRIMO. Dose distributions and dose volume histogram (DVH) curves were compared between validated and artificial cases with overestimated energy. Initial mean energies were obtained of 6.68, 9.73, 13.2 and 16.4 MeV for 6, 9, 12 and 15 nominal energies, respectively. Energy FWHM reduced with increase in energy. Three mm focal spot FWHM for 9 MeV and 4 mm for other energies made proper matches of simulated and measured profiles. In addition, the maximum difference of calculated mean electrons energy at the phantom surface with empirical equation was 2.2 percent. Finally, clear differences in DVH curves of validated and artificial energy were observed as heterogeneity indexes were 0.15 for 7.21 MeV and 0.25 for 6.68 MeV. The Monte Carlo model presented in PRIMO for Varian 2100 CD was precisely validated. IAEA polynomial equations estimated mean energy more accurately than a known linear one. Small displacement of R50 changed DVH curves and homogeneity indexes. PRIMO is a user-friendly software which has suitable capabilities to calculate dose distribution in water phantoms or computerized tomographic volumes accurately.
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http://dx.doi.org/10.7314/apjcp.2015.16.17.7795DOI Listing
September 2016