How Should Governments Address High Levels of Natural Radiation and Radon--Lessons from the Chernobyl Nuclear Accident and Ramsar, Iran

The authors discuss the high levels of natural background radiation in Ramsar, Iran, and offer data indicating that this has had little effect on the health of Ramsar\u27s inhabitants. The authors then examine the implications their research could have for public health policy

Green synthesis of silver nanoparticles (AgNPs) by Lallemantia royleana leaf Extract: Their Bio-Pharmaceutical and catalytic properties

The study of the silver nanoparticles (AgNPs) synthesis based-green methods become more interesting recently due to their low-cost preparation, eco-friendly and non-toxic precursors. The present study approved the ability of the Lallemantia royleana (Benth. in Wall.) Benth. leaf extract for the synthesis of AgNPs for the first time. The synthesized AgNPs were physico-chemical characterized using ultraviolet–visible spectroscopy (UV–Vis), X-ray diffraction (XRD), Fourier Transform-Infrared Spectroscopy (FT-IR), zeta potential and transmission electron microscopy (TEM) analysis. The total phenols, flavonoids, anthocyanin, tannin contents, antioxidant, antimicrobial, anti-inflammatory, anti-arthritic and cytotoxic activities of L. royleana leaf extract and the synthesized AgNPs were investigated. The biocatalytic activity of prepared AgNPs was assessed on methylene blue as a pollutant organic dye. The TEM examination showed that the synthesized AgNPs were predominantly spherical with some mixed shapes and crystalline with average size 34.47 ± 1.6 nm, and showed a localized surface plasmon resonance (LSPR) peak at 425 nm. The zeta potential value was −24.1 mV indicating the stability of produced AgNPs. The new prepared AgNPs have lower total phenols, flavonoids, anthocyanin, tannin contents than L. royleana leaf extract. In addition, the new prepared AgNPs demonstrated the higher DPPH radical scavenging activity (87 %) and the ABTS radical scavenging activity (77 %) at the maximum prepared concentration of 250 μg mL−1 as compared to the L. royleana leaf extract (62 % and 58 %, respectively). The produced AgNPs also exhibited the higher antimicrobial activity against both the Gram-positive (Staphylococcus aureus and Bacillus cereus) and the Gram-negative (Escherichia coli and Shigella flexneri) bacteria and the Candida strains (Candida glabrata and Candida albicans) as compared to the L. royleana leaf extract. The resulting AgNPs indicated a dose-dependent anti-inflammatory effect on human red-blood cell (RBC) membrane stabilization assay and had more activity (72 %) compared to the L. royleana leaf extract (61 %) at 250 µg mL−1. The prepared AgNPs showed promising in vitro anti-arthritic activity evaluated by 73 % compared to 58 % in case of L. royleana leaf extract. The new produced AgNPs showed the higher cytotoxic effect against the human hepatoma (Hep-G2) and the human breast (MCF-7) cancer cells compared to the L. royleana leaf extract with 79.3 % and 77.2 % at 250 µg/mL, respectively. The obtained results revealed also that the green synthesized AgNPs were capable to catalyze MB dye. Therefore, the obtained results provide a promising route of the green synthesis of AgNPs using L. royleana leaf extract with considerable biopharmaceuticals and catalytic applications

Antioxidants: Positive or Negative Actors?

The term "antioxidant" is one of the most confusing definitions in biological/medical sciences. In chemistry, "antioxidant" is simply conceived "a compound that removes reactive species, mainly those oxygen-derived", while in a cell context, the conceptual definition of an antioxidant is poorly understood. Indeed, non-clinically recommended antioxidants are often consumed in large amounts by the global population, based on the belief that cancer, inflammation and degenerative diseases are triggered by high oxygen levels (or reactive oxygen species) and that through blocking reactive species production, organic unbalances/disorders can be prevented and/or even treated. The popularity of these chemicals arises in part from the widespread public mistrust of allopathic medicine. In fact, reactive oxygen species play a dual role in dealing with different disorders, since they may contribute to disease onset and/or progression but may also play a key role in disease prevention. Further, the ability of the most commonly used supplements, such as vitamins C, E, selenium, and herbal supplements to decrease pathologic reactive oxygen species is not clearly established. Hence, the present review aims to provide a nuanced understanding of where current knowledge is and where it should go.Antoni Sureda acknowledges the support of Institute of Health Carlos III (Project CIBEROBNCB12/03/30038). Natália Martins thank to Portuguese Foundation for Science and Technology (FCT–Portugal) for the Strategic project ref. UID/BIM/04293/2013 and “NORTE2020-Programa Operacional Regional do Norte” (NORTE-01-0145-FEDER-000012)

Federated Learning in Medical Imaging:Part I: Toward Multicentral Health Care Ecosystems

With recent developments in medical imaging facilities, extensive medical imaging data are produced every day. This increasing amount of data provides an opportunity for researchers to develop data-driven methods and deliver better health care. However, data-driven models require a large amount of data to be adequately trained. Furthermore, there is always a limited amount of data available in each data center. Hence, deep learning models trained on local data centers might not reach their total performance capacity. One solution could be to accumulate all data from different centers into one center. However, data privacy regulations do not allow medical institutions to easily combine their data, and this becomes increasingly difficult when institutions from multiple countries are involved. Another solution is to use privacy-preserving algorithms, which can make use of all the data available in multiple centers while keeping the sensitive data private. Federated learning (FL) is such a mechanism that enables deploying large-scale machine learning models trained on different data centers without sharing sensitive data. In FL, instead of transferring data, a general model is trained on local data sets and transferred between data centers. FL has been identified as a promising field of research, with extensive possible uses in medical research and practice. This article introduces FL, with a comprehensive look into its concepts and recent research trends in medical imaging

Federated Learning in Medical Imaging:Part II: Methods, Challenges, and Considerations

Federated learning is a machine learning method that allows decentralized training of deep neural networks among multiple clients while preserving the privacy of each client's data. Federated learning is instrumental in medical imaging due to the privacy considerations of medical data. Setting up federated networks in hospitals comes with unique challenges, primarily because medical imaging data and federated learning algorithms each have their own set of distinct characteristics. This article introduces federated learning algorithms in medical imaging and discusses technical challenges and considerations of real-world implementation of them

Age-associated changes on axonal regeneration and functional outcome after spinal cord injury in rats

This study was conducted to evaluate the association between aging and regenerative potential of spinal cord injury. Three groups of male Sprague�Dawley rats, including young (40 days), mature (5-6 months) and old (28-29 months) were spinally hemisected at the L1 level. The locomotor performance was assessed weekly for eight weeks after lesion using locomotors� rating scale developed by Basso, Bresnahan and Beattie (BBB). In the tracing study, retrograde labeled neuron was counted in the lateral vestibular nucleus for axonal regeneration. From 4-8 weeks, the functional recovery of the young and mature age rats was significantly increased in comparison to the old age group. At 8 weeks, young and mature animals achieved a plateau score of (mean ± SD), 17 ± 1.47 and 16.8 ± 0.70 respectively, and the old rats reached an average score of 13.8±1.63 (P<0.05). The mean number of labeled neurons in the vestibular nucleus in the young group (mean ± SD): 32.05 ± 1.03 increase significantly compared to the older age group 5.01 ± 1.31 (P<0.05). Current findings suggest that axonal repair and functional improvement decrease in aged animals after partial spinal cord injury. Thus, the aging process may affect the regenerative capacity of the injured central nervous system, and axonal regeneration is age dependent. © 2015 Tehran University of Medical Sciences. All rights reserved

Drug release, cytocompatibility, bioactivity, and antibacterial activity of doxycycline loaded Mg-Ca-TiO2 composite scaffold

Mg-Ca-TiO2 (MCT) composite scaffolds loaded with different concentrations of doxycycline (DC) with a network of interconnected pores with good compressive strength (5 ± 0.1 MPa) were fabricated via space holder method for the first time. The results showed that MCT-DC scaffolds possess a porosity and pore size in the range of 65–67% and 600–800 μm respectively. The bioactivity results exhibited the apatite formation on the MCT-DC scaffold surface, indicating that DC did not obstruct the bioactivity of MCT. The MCT-DC scaffolds drug release profiles show the initial burst and sustained drug release (55–75%) and the release rate could be adjusted via altering the DC concentration. The MCT loaded with 1 and 5% DC did not indicate cytotoxic behavior against MG63 cells while further DC loading resulted in some toxicity. Antimicrobial properties of MCT-DC scaffolds against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria were examined and the results reveal oblivious inhibition zone around each MCT-DC scaffold whereas no obvious inhibition is observed around the MCT scaffold. Therefore, MCT-DC composite scaffolds with low concentration of DC could be alternative candidates for infection prevention and bone tissue engineering

Design and Validation of Synchronous QCT Calibration Phantom: Practical Methodology

Introduction: Quantitative computed tomography (QCT) can supplement dual x-ray absorptiometry by enabling geometric and compartmental bone assessments. Whole-body spiral CT scanners are widely available and require a short scanning time of seconds, in contrast to peripheral QCT scanners, which require several minutes of scanning time. This study designed and evaluated the accuracy and precision of a homemade QCT calibration phantom using a whole-body spiral CT scanner. Materials and Methods: The QCT calibration phantom consisted of K 2 HPO 4 solutions as reference. The reference material with various concentrations of 0, 50, 100, 200, 400, 1000, and 1200 mg/cc of K 2 HPO 4 in water were used. For designing the phantom, we used the ABAQUS software. Results: The phantoms were used for performance assessment of QCT method through measurement of accuracy and precision errors, which were generally less than 5.1 for different concentrations. The correlation between CT numbers and concentration were close to one (R 2 = 0.99). Discussion: Because whole-body spiral CT scanners allow central bone densitometry, evaluating the accuracy and precision for the easy to use calibration phantom may improve the QCT bone densitometry test. Conclusion: This study provides practical directions for applying a homemade calibration phantom for bone mineral density quantification in QCT technique. © 201

The analysis of anticcp antibodies in the serum: a comparison between the patients with rheumatoid arthritis

Rheumatoid Arthritis (RA) is a chronic systemic autoimmune disease that causes inflammation, pain, stiffness and destructive changes in the joints. Although, Rheumatoid Factor (RF), has been the primary blood test used to detect RA, the anti-ccp antibodies detection test is a relatively new assay to detect the citrulline antibodies in blood. These autoantibodies are produced by immune system in response to a perceived threat of citrulline, an amino acid produced from arginine in the citrullination process. The objective of this study was to investigate the presence and prediction value of anti-ccp in RA patients and evaluate its sensitivity and specificity comparing to that of classic laboratory tests, CRP and RF. The serum of 84 patients with RA and 80 healthy control subjects were enrolled into the study. The anti-ccp, RF and CRP levels in the serums were assayed by ELISA and agglutination procedure, respectively. Our results provided evidence that anti-ccp level was significantly higher in patients with RA comparing to that of corresponding controls (p<0.0001). Anti-ccp was found to have the highest sensitivity and specificity (91%-91%) comparing to the other two tests (RF, CRP). The latter tests were found to have (97%- 92%) and (27%- 75%) sensitivity and specificity, respectively. The diagnostic value of anti-ccp is better than RF and CRP, individually. It can be detected early in the disease in unselected early arthritis patients. It is recommended to use RF test together with anti-ccp antibodies detection, in RA patients to ensure a higher diagnostic effectiveness