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In this study, 3D-printed reinforced concrete beams were tested for flexural performance and compared with the analytical model based on the material test results. Two cementitious mixes (PSU and GCT) were designed for concrete printing and were mechanically tested and compared. Anisotropies in the compressive strength and modulus of elasticity of printed concrete were observed, applied to the analytical prediction of flexural bending behavior, and validated by actual test results. Significant differences between analytical predictions and experimental tests of the bending behaviors of the printed concrete beams were observed. Furthermore, higher compressive strengths and moduli of elasticity were observed when the loading direction was perpendicular to the printed layers or with the PSU mix. The effect of anisotropic mechanical properties on a reinforced beam was compared to the flexural bending tests for both mixes. The analytical model based on the material test results was compared to the flexural bending test results. The significant errors in the prediction of printed concrete's structural performance, from 10% to 50%, suggest that factors other than reduced compressive strengths may influence the structural behaviors of printed concrete beams. [ABSTRACT FROM AUTHOR]

C-reactive protein (CRP) is a beneficial diagnostic test for the evaluation of inflammatory response. Extremely low levels of CRP can be detected using high-sensitivity CRP (hs-CRP) test. A considerable body of evidence has demonstrated that inflammatory response has an important role in the pathophysiology of autism. In this study, we evaluated and compared hs-CRP levels between autistic and intellectually normal individuals. Clinical data of 39 autistic and 30 age-matched intellectually normal individuals (control group) were recorded. Patients were divided into two groups (mild-to-moderate and severe) according to childhood autism rating scale. Then serum hs-CRP concentrations were measured and compared between two groups. Also, the correlation between hs-CRP concentration and the severity of autism was determined. The mean concentration of hs-CRP in children with autism (540.1 plus or minus 1125.5 ng/ml) was significantly (P less than 0.0001) higher than control group (1.3 plus or minus 1.0 ng/ml). In severe autism, the mean level of hs-CRP (985.1 plus or minus 1432.1 ng/ml) was significantly (P = 0.008) higher than the mean level of hs-CRP in patients with mild-to-moderate autism (147.1 plus or minus 60.4 ng/ml). There was a positive correlation between hs-CRP concentration and autism severity (r = 0.34; P = 0.039). These findings affirm the role of inflammation in autism. (Contains 1 table and 2 figures.)

Objective Transforming growth factor-beta (TGF-β), a group of multifunctional growth factors, plays an important role in the neuron survival and neurodevelopmental functions. Some studies have evaluated the correlation between TGF-β1 and TGF-β2 abnormalities and autism spectrum disorders. In this study, we compared the TGF-β1 and TGF-β2 levels between autistic and intellectually normal individuals. Materials & Methods The study population consisted of 39 autistic and 30 age-matched intellectually normal individuals (control group). Blood samples were taken from all individuals, and all patients were divided into 2 groups (mild-to-moderate and severe) according to the childhood autism rating scale. The cytokines levels were measured by Enzyme Linked Immunosorbent Assay (ELISA). Results The mean concentration of TGF-β1 was significantly lower (P < 0.0001) in children with autism compared to the control group (25.3 ± 6.5 versus 35.1 ± 9.4 ng/mL, respectively). Also, the mean concentration of TGF-β2 in children with autism (32.35± 7.75 ng/ mL) was higher compared to those in the control group (30.47± 4.36 ng/mL); however, this difference did not reach statistical significance (P = 0.21). A positive correlation was observed between TGF-β1 concentration and autism severity (r = 0.41; P = 0.02), whereas a negative correlation was found between TGF-β2 concentration and autism severity (r = -0.41; P = 0.02). Conclusion The results of the present investigation suggest that there is a decrease in the levels of TGF-β1 in the serum of patients with autism and this cytokine may be effective in the treatment of the pathophysiological aspects of autism. [ABSTRACT FROM AUTHOR]

Background and purpose: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major hospital and non-hospital pathogens in children. This meta-analysis and systematic review aimed at exploring the data on prevalence of MRSA in Iranian children. Materials and methods: Primary articles in English and Persian were searched using the following keywords: prevalence, children, methicillin-resistant staphylococcus aureus (MRSA), and Iran. Electronic databases, including Pubmed, Web of Science, Google Scholar and Iranian databases such as Magiran and SID were searched for articles published in 2007-2019. Qualitative assessment of studies was done using STROBE checklist and data analysis was done in STSTA V11. Results: A total of 55 articles were identified and 23 met the study inclusion criteria. The prevalence of MRSA in children with S. aureus infection was 22%. The prevalence of community acquired and nosocomial MRSA was 17% and 38%, respectively. Conclusion: The current meta-analysis showed considerable rates of nosocomial and community acquired MRSA infections among children in Iran. So, pediatricians should consider this issue in empirical treatment [ABSTRACT FROM AUTHOR]

Background: Autism is a pervasive disorder and its prevalence increased in recent surveys. An estimated 1 out of every 88 children is affected by autism. Autism disorder symptoms appear before the age of three. It is believed that serum levels of superoxide dismutase may play a role in etiology of autism. Materials and methods: Between October and November 2014, 27 Iranian children from Mashhad city were selected in this study. Given these assumptions, the amount of SOD serum in autistic patients and healthy individuals and correlation between the amount of SOD and autism severity were examined. Blood samples of 30 autistic children and 18 age-matched healthy children were collected between 9 to 11 am. Serum level of SOD in both groups was measured by ELISA method. Results: The mean SOD level in the treatment group (1.04 ±1.33 ng/ml) was significantly lower than the control group (p = 0.001). However, SOD level was not significantly associated with the autism severity (p = 0.667). Conclusions: Decreased serum levels of superoxide dismutase in the early diagnosis of autistic children can be considered as a diagnostic biomarker. [ABSTRACT FROM AUTHOR]