Effect of Blast Loading on Seismically Detailed RC Columns and Buildings

Explosions caused by standoff charges near buildings have drastic effects on the internal and external structural elements which can cause loss of life and fatal injuries in case of failure or collapse of the structural element. Providing structural elements with blast resistance is therefore gaining increasing importance. This paper presents numerical investigation of RC columns with different reinforcement detailing subjected to near-field explosions. Detailed finite element models are made using LS-DYNA software package for several columns having seismic and conventional reinforcement detailing which were previously tested under blast loads. The numerical results show agreement with the published experimental results regarding displacements and damage pattern. Seismic detailing of columns enhances the failure shape of the column and decrease the displacement values compared to columns with conventional reinforcement detailing. Further, the effect of several modeling parameters are studied such as mesh sensitivity analysis, inclusion of air medium and erosion values on the displacements and damage pattern. The results show that decreasing the mesh size, increasing erosion value and inclusion of air region provide results that are very close to experimental results. Additionally, application is made on a slab-column multistory building provided with protective walls having different connection details subjected to blast loads. The results of this study are presented and discussed. Use of a top and bottom floor slab connection of protective RC walls are better than using the full connection at the four sides to the adjacent columns and slabs. This leads to minimizing the distortion and failure of column, and therefore it increases the chance of saving the building from collapse and saving human lives. Doi: 10.28991/cej-2021-03091733 Full Text: PD

Methylene tetrahydrofolate reductase, transforming growth factor-β1 and lymphotoxin-α genes polymorphisms and susceptibility to rheumatoid arthritis

AbstractBackgroundRheumatoid arthritis is a widely prevalent autoimmune disorder with suggested genetic predisposition.ObjectivesThe aim of this study is to detect the pattern of genetic polymorphism of methylene tetrahydrofolate reductase (MTHFR C677 T and A1298 C), transforming growth factor-β1 (TGF-β1 T869 C) and lymphotoxin-α (LT-α A252G) in patients having rheumatoid arthritis and correlate these patterns to disease activity and serum levels of tumor necrosis factor-alpha (TNF-α), B-Cell Activating Factor (BAFF), and osteopontin.MethodsA total of 194 subjects, 90 controls and 104 patients with rheumatoid arthritis were genotyped for MTHFR C677 T and A1298 C, TGF-β1 T869 C and LT-α A252G polymorphisms using a methodology based on PCR-RFLP. Also serum levels of TNF-α, osteopontin and BAFF were measured by ELISA kits.ResultsThe CT genotype and T allele of MTHFR C677 T and GG genotype and G allele of LT-α A252G are associated with the risk of RA and with higher levels of the pro-inflammatory cytokine, TNF-α in patients with rheumatoid arthritis.ConclusionOur findings suggest that there is association between MTHFR C677 T and LT-α A252G genes polymorphisms and increased risk of RA in this sample of Egyptian population

Polimorfismos dos genes metilenotetrahidrofolato redutase, fator de crescimento transformador β1 e linfotoxina‐α e susceptibilidade à artrite reumatoide

ResumoAntecedentesA artrite reumatoide é uma doença autoimune amplamente prevalente com sugerida predisposição genética.ObjetivosDetectar o padrão de polimorfismo dos genes metilenotetrahidrofolato redutase (MTHFR C677T e A1298C), fator de crescimento transformador β1 (TGF‐β1 T869C) e linfotoxina‐α (LT‐α A252G) em pacientes com artrite reumatoide e correlacionar esses padrões com a atividade da doença e os níveis séricos de fator de necrose tumoral alfa (TNF‐α), fator ativador de linfócitos B (BAFF) e osteopontina.MétodosForam genotipados 194 indivíduos – 90 controles e 104 com artrite reumatoide – à procura de polimorfismos dos genes MTHFR C677T e A1298C, TGF‐β1 T869C e LT‐α A252G com uma metodologia baseada na PCR‐RFLP. Mensuraram‐se também os níveis séricos de TNF‐α, osteopontina e BAFF com kits de Elisa.ResultadosO genótipo CT e o alelo T do MTHFR C677T e o genótipo GG e alelo G do LT‐α A252G estão associados ao risco de AR e a níveis mais elevados da citocina pró‐inflamatória TNF‐α em pacientes com artrite reumatoide.ConclusãoOs achados do presente estudo sugerem que há associação entre os polimorfismos dos genes MTHFR C677T e LT‐α A252G e um risco aumentado de AR nessa amostra da população egípcia.AbstractBackgroundRheumatoid arthritis is a widely prevalent autoimmune disorder with suggested genetic predisposition.ObjectivesThe aim of this study is to detect the pattern of genetic polymorphism of methylene tetrahydrofolate reductase (MTHFR C677T and A1298C), transforming growth factor‐β1 (TGF‐β1 T869C) and lymphotoxin‐α (LT‐α A252G) in patients having rheumatoid arthritis and correlate these patterns to disease activity and serum levels of tumor necrosis factor‐alpha (TNF‐α), B‐Cell Activating Factor (BAFF), and osteopontin.MethodsA total of 194 subjects, 90 controls and 104 patients with rheumatoid arthritis were genotyped for MTHFR C677T and A1298C, TGF‐β1 T869C and LT‐α A252G polymorphisms using a methodology based on PCR‐RFLP. Also serum levels of TNF‐α, osteopontin and BAFF were measured by ELISA kits.ResultsThe CT genotype and T allele of MTHFR C677T and GG genotype and G allele of LT‐α A252G are associated with the risk of RA and with higher levels of the pro‐inflammatory cytokine, TNF‐α in patients with rheumatoid arthritis.ConclusionOur findings suggest that there is association between MTHFR C677T and LT‐α A252G genes polymorphisms and increased risk of RA in this sample of Egyptian population

Efficiency of coating layers used for thermal protection of FRP strengthened beams

This paper investigates the efficiency of coating layers used for thermal protection of Fiber-Reinforced Polymer (FRP) strengthened Reinforced Concrete (RC) beams. An experimental program was carried out on 36 RC beams protected by using different coating layers of Perlite, Vermiculite, Portland Cement (PC) mortar, clay and ceramic fiber. The tested beams were exposed to 100, 200, 300, 400, 500, and 600 °C for 2 h, left to cool gradually, then tested to failure. The obtained results demonstrated that exposure to elevated temperature without protection reduces the residual flexural strength of RC beams by 20–66%, depending on the degree of temperature. Protecting RC beams by a 30 mm-thick layer of the tested materials was demonstrated to be efficient in reducing heat transfer through 2-h exposure to 600 °C, and thus provide higher fire rating. Protection layers of cement mortar, Aswan clay, Vermiculite, Perlite and ceramic fiber blanket, showed residual flexural capacity equal to 61%, 68%, 72%, 73% and 74% that of the control beam, respectively. Moreover, using double coating layers of ceramic fiber followed by Perlite plaster, Vermiculite plaster, PC plaster or Aswan clay, with overall total thickness of 50 mm was demonstrated to give better protection, and maintain residual flexural capacity only 5% less than the flexural capacity of control beams

Association of interleukin-23 receptor (IL-23R) gene polymorphisms (rs11209026, rs2201841 and rs10889677) with Egyptian rheumatoid arthritis patients

AbstractAim of the workTo analyse interleukin 23 receptors (IL23R) single-nucleotide polymorphism (SNPs) (rs11209026, rs2201841, and rs10889677) and to detect their association with Egyptian rheumatoid arthritis (RA) patients.Patients and methodsThe study included 120 Egyptian RA patients and 120 healthy controls that were genotyped for the three SNPs by real time/polymerase chain reaction for the first SNP and restriction fragment length polymorphism/PCR (RFLP/PCR) in the last two SNPs. The disease activity score (DAS28) was assessed in the patients.ResultsThe studied patients had a mean age of 42.5±13.4years, a disease duration of 5.2±3.5years and consisted of 22 males and 98 females. Joint deformities were present in 35 and 66 patients had swollen joints. The rheumatoid factor (RF) was positive in 78.3% and the DAS28 was 3.2±1.2. Our data emphasize that the AA genotype of rs11209026 was significantly associated with RA patients compared to the controls (p=0.001). We did not find any significant association between either rs2201841 or rs10889677 and the development of RA (p=1, p=0.56 respectively). The AA allele in the 3 SNPs were remarkable frequent in those with deformities and positive RF.ConclusionOur results suggest that IL23 receptor AA genotype variant of rs11209026 contributes to the aetiology of RA and may be considered a genetic marker and shared the susceptibility gene. We need to address the subgroup of patients who will benefit from the selective suppression of the IL-23 signalling which would represent new perspectives towards a personalized therapy of RA patients by further studies

Haptoglobin phenotypes as a risk factor for coronary artery disease in type 2 diabetes mellitus: An Egyptian study

Objective: Diabetes has long been known to be an independent risk factor for cardiovascular disease. Recognition of diabetic individuals at greatest risk of developing coronary artery disease (CAD) would have important public health importance by allowing the distribution of limited resources to be directed on those who would most benefit from aggressive management. Several functional differences between haptoglobin (Hp) phenotypes have been demonstrated that appear to have important biological and clinical consequences in the development of CAD in patients with type 2 DM. The present study was conducted to demonstrate the relationship between the Hp phenotypes and the development of CAD among Egyptian patients with type 2 DM. To our knowledge this work had not been carried out in Egypt before. Subjects and methods: The study included 160 subjects divided into three groups. Group I: 72 type 2 DM patients without CAD, Group II: 48 type 2DM patients with developed CAD, Group III: 40 age and gender matched apparently healthy subjects to serve as controls. All patients and controls were subjected to full history taking, complete clinical examination, and routine laboratory investigations. Serum C-reactive protein (CRP) levels and serum haptoglobin levels were measured. Polymerase chain reaction (PCR) was used for Hp phenotypes’ determination. Results: Analysis revealed association between Hp2-2 phenotype and the presence of CAD in type 2 DM. Hp and CRP serum levels were significantly higher in patients with CAD. Although the levels of Hp did not reach significance among patients with different Hp phenotypes yet the individual with Hp2-2 phenotype had trend toward higher level. Conclusion: Hp2-2 phenotype is considered to be a major susceptibility gene for the development of CAD in type 2 DM. Awareness of this gene susceptibility should raise future research for proper treatment and prevention of CAD development in type 2 DM

Methylene tetrahydrofolate reductase, transforming growth factor-β1 and lymphotoxin-α genes polymorphisms and susceptibility to rheumatoid arthritis

ABSTRACT Background: Rheumatoid arthritis is a widely prevalent autoimmune disorder with suggested genetic predisposition. Objectives: The aim of this study is to detect the pattern of genetic polymorphism of methylene tetrahydrofolate reductase (MTHFR C677 T and A1298 C), transforming growth factor-β1 (TGF-β1 T869 C) and lymphotoxin-α (LT-α A252G) in patients having rheumatoid arthritis and correlate these patterns to disease activity and serum levels of tumor necrosis factor-alpha (TNF-α), B-Cell Activating Factor (BAFF), and osteopontin. Methods: A total of 194 subjects, 90 controls and 104 patients with rheumatoid arthritis were genotyped for MTHFR C677 T and A1298 C, TGF-β1 T869 C and LT-α A252G polymorphisms using a methodology based on PCR-RFLP. Also serum levels of TNF-α, osteopontin and BAFF were measured by ELISA kits. Results: The CT genotype and T allele of MTHFR C677 T and GG genotype and G allele of LT-α A252G are associated with the risk of RA and with higher levels of the pro-inflammatory cytokine, TNF-α in patients with rheumatoid arthritis. Conclusion: Our findings suggest that there is association between MTHFR C677 T and LT-α A252G genes polymorphisms and increased risk of RA in this sample of Egyptian population