How efficient are metal-polymer and dual-metals-polymer non-lead radiation shields?

INTRODUCTION: Lead shields are often used to attenuate ionising radiations. However, to make lighter, recyclable and more efficient shields compared to lead, combinations of new metallic compounds together with polymer, for example, flexible polyvinyl chloride (PVC) have been developed recently. In this study, the capabilities of non-lead radiation shields made of one or two metallic compounds and polymer were evaluated. METHODS: Monte Carlo (MC)-based BEAMnrc code was used to build a functional model based on a Philips X-ray machine in the range of radiographic energies. The MC model was then verified by IPEM Report 78 as a standardised global reference. The MC model was then used to evaluate the efficiency of non-lead-based garments made of metallic compound and polymer (MCP) including BaSO4 -PVC, Bi2 O3 -PVC, Sn-PVC and W-PVC, as well as dual-metallic compounds and polymer (DMCP) including Bi2 O3 -BaSO4 -PVC, Bi2 O3 -Sn-PVC, W-Sn-PVC and W-BaSO4 -PVC. The absorbed doses were determined at the surface of a water phantom and compared directly with the doses obtained for 0.5 mm pure lead (Pb). RESULTS: Bi2 O3 -BaSO4 -PVC and W-BaSO4 -PVC were found to be efficient shields for most of the energies. In addition to the above radiation shields, Bi2 O3 -Sn-PVC was also found to be effective for the spectrum of 60 keV. Bi2 O3 -BaSO4 -PVC as a non-lead dual metals-PVC shield was shown to be more efficient than pure lead in diagnostic X-ray range. CONCLUSION: Combination of two metals-PVC, a low atomic number (Z) metal together with a high atomic number metal, and also single-metal-PVC shields were shown to be efficient enough to apply as radiation protection shields instead of lead-based garments.

Development of a scenario-based blood bank model to maximize reducing the blood wastage.

INTRODUCTION: Blood is a valuable as well as a perishable commodity that has a limited lifespan. So, keeping it in a blood bank requires careful attention and management. In this study, a management model has been designed for the blood bank that can cover all the requests sent through the hospital subunits in such a way that it has the least waste. MATERIALS AND METHODS: First, by examining the blood inventory system of a hospital, the number of inventories per month and the distribution of blood products in subunits of the hospital, and the amount of blood wastage every six months were estimated. Then, using ARENA simulation, all parts of the blood bank, including the request section, emergency blood section, donated blood section, and other sections were simulated. Finally, 10 scenarios were extracted by placing various parameters and the best scenarios were discussed and concluded. RESULTS AND DISCUSSION: The scenarios for the four blood groups included A, B, AB, and O were applied for six months in one year. The results showed that if the amount of blood injected into the blood bank is appropriate and at the right time, the amount of wastage can be reduced by up to 80% for most of the blood groups. CONCLUSION: The results of this study showed that if the system of receiving blood products built upon a precise management model is predetermined and placed with appropriate parameters, the amount of wastage will be reduced to the minimum possible number.

Ce/Eu redox couple functionalized HKUST-1 MOF insight to sono-photodegradation of malathion.

The Ce/Eu redox pair-functionalized HKUST-1 MOF, as an innovative environmentally friendly and recyclable sono-photocatalyst, was hydrothermally mixed and fully characterized by XRD, PL, EIS, FE-SEM, EDS, Mott-Schottky, chronoamperometry, and DRS techniques. The obtained chemical and optical characteristics of the n-type Ce/Eu-HKUST-1 MOF showed that the transfer of additional 4f orbital electrons in the Ce/Eu redox pair improves the sono-photocatalytic activity. The performance of Ce/Eu-HKUST-1 MOF for the sono-photodegradation of Malathion (MA) was evaluated in the aqueous media in the simultaneous presence of blue light and ultrasonic irradiation. The optimization of the process was cross-examined using the response surface methodology as a function of the MA concentration (15-35 mg·L-1), Ce/Eu-HKUST-1 mass (10-30 mg), pH (4-12), and ultrasonic wave irradiation duration (10-30 min). The maximum sono-photocatalytic degradation capacity was found to be 99.99% under the optimum conditions set as 25 mg·L-1, 20 mg, 8, and 25 min for the concentration of Malathion, photocatalyst mass, pH, and irradiation duration, respectively. These findings were attributed to the suppression of electron-hole pair recombination, increased life-time of charge carriers, enhanced visible light absorption, and prominent proportion of hydroxyl and peroxide radicals formed.

A study to assess the knowledge and practice of medical professionals on radiation protection in interventional radiology.

OBJECTIVE: Ionizing radiation has been extensively used in medical procedures throughout the world. Such interventional radiological procedures could result in occupational exposure that needs urgent control. Therefore, MPs (medical professionals) should receive education and appropriate training on occupational radiation protection. In this context, the present study is aimed to investigate the MPs' knowledge and practice regarding radiation protection principles during interventional radiological procedures. MATERIAL AND METHODS: A descriptive questionnaire-based study was carried out among 215 MPs involved in interventional fluoroscopy procedures. The practice of 31 MPs was studied using a checklist based on ALARA principles and ICRP guidelines. RESULTS: A total of 43.3% and 45.1% answered correctly for knowledge and practice. However, the difference between radiation protection knowledge and practice between the physicians and nurses was statistically significant. The knowledge and practice survey of MPs demonstrated that nurses rarely adhered to radiation-protection measures. CONCLUSION: The present study reflects the lack of knowledge and practice concerning radiation protection concepts among the nurses. This deficiency needs to be resolved by periodic practical radiation protection courses in the curriculum of medicine.

Circular RNAs in ß-cell function and type 2 diabetes-related complications: a potential diagnostic and therapeutic approach.

Recent investigations have indicated that altered expression of non-coding RNAs (ncRNAs) could be associated with human diseases such as type 2 diabetes (T2D). Circular RNAs (circRNAs) are a new discovered class of ncRNAs with unique structural characteristics that involved in several molecular and cellular functions. Exploring of the circulating circRNAs as a reliable non-invasive biomarker for monitoring and diagnosing of human diseases has grown significantly. However, the molecular functions and clinical relevance of circRNAs are not yet well clarified in T2D. Accordingly, in this review, the involvement of circRNAs in the ß-cell function and T2D-related complications is highlighted. The study also shed light on the possibility of using circRNAs as a biomarker for T2D diagnosis.

Co-expression profiling of plasma miRNAs and long noncoding RNAs in gastric cancer patients.

PURPOSE: The recent researches indicate that differential non-coding RNAs expression signatures could be associated with the pathogenesis of gastric cancer (GC). However, there are few studies focused on lncRNA-miRNAs co-expression profiling in GC patients. Therefore, in the present study the expression of H19 and MEG3 and their related miRNAs including miR-148a-3p, miR-181a-5p, miR-675-5p and miR-141-3p were determined in the plasma samples of GC patients and controls. MATERIALS AND METHODS: This case-control study included 62 GC patients and 40 age- sex matched controls. The non-coding RNA levels were assessed by real-time PCR. Further, using in silico analysis, we identified shared targets of studied miRNAs and performed GC-associated pathway enrichment analysis. RESULTS: Our results showed that the H19 level was significantly (P = 0.008) elevated and MEG3 expression was significantly (P = 0.002) down-regulated in GC patients compared to healthy participants. Furthermore, it was revealed that the miR-675-5p level was increased, while miR-141-3p plasma levels were significantly reduced in GC patients (P < 0.05). We did not observe a significant difference for miR-148a-3p (P = 0.682) and miR-181a-5p (P = 0.098) expression between groups. In addition, the expression levels of H19, MEG3 and miR-148a-3p were associated with some clinicopathological features of patients (P < 0.05). ROC analysis revealed that a combination of H19, MEG3 and miR-675-5p levels able to discriminate controls and GC subjects with 88.87% sensitivity and 85% specificity (AUC, 0.927; 0.85-0.96 CI, P < 0.0001). CONCLUSION: The results of current study demonstrated that combination of H19, MEG3 and miR-675-5p expression levels could provide a potential diagnostic panel for GC.