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Hydrogen embrittlement behaviors of tubular steel API-P110 in the acid solution dissolved 50% H2S and 50% CO2 or 50% H2S only were investigated by immersion test, sulfide stress cracking corrosion (SSC) at the constant loading, and electrochemical hydrogen permeation test. Effects of CO2 on hydrogen embrittlement corrosion behavior are discussed. Compared to that of steels without being corroded, in H2S and CO2S or H2S only, the tensile strength(σb), yield strength (σs) and elongation rate at rupture(δc) of steel decline; comparing with in H2S only, the strength and elongation of steel in H2S and CO2 decline less, embrittlement rate is low, the SSC susceptibility of steel lightens, and hydrogen permeation rate(J) decreases. In various corrosive environment, hydrogen permeation density (JH) dramatically increases to peak value as time goes on, then descend slowly until the steady state appears. In high H2S, CO2 improves compactness of corrosion scale, and decreases the content of FexSy in scale. Therefore, the amount of hydrogen permeation in H2S and CO2 is more than in H2S only, as results in the susceptibility of hydrogen embrittlement of steel decreases. [ABSTRACT FROM AUTHOR]

Objective: To observe the status of iron deposition in patient with β thalassemia major, and to formulate appropriate treatment strategies., Method: The data of status of transfusion and chelation in 135 patients aged from 6 years and 4 months to 17 years and 11 months with β thalassemia major were collected and analyzed. Serum ferritin levels were determined and cardiac and hepatic iron deposition was determined using MRI T2(*) technology., Result: Of the 135 cases studied, 66 were male, and 69 were female, their average age was 12.1 years. Serum ferritin (SF) was determined for 111 cases, it varied from 1 086.8 µg/L to 15 011.5 µg/L. Among them, 16 cases had SF level <2 000 µg/L (14.5%) , in 41 cases SF were between 2 000 and 4 000 µg/L (36.0%) ;in 54 cases SF >4 000 µg/L (48.7%) . Liver MRI T2(*) results showed that in only 8 cases (5.9%) iron content in the liver was in normal range, 19 cases (14.9%) showed mild liver iron deposition;34 (25.2%) moderate and 74 (54.8%, the youngest one was only 6 years and 4 months of age) had severe iron deposition respectively. Cardiac MRI T2(*) showed that in 89 cases (65.9%) iron content in the heart was in normal range;19 cases (14.1%) had mild cardiac iron deposition and 27 (20.0%) presented severe iron deposition (the youngest one was only 9 years and 3 months of age) . SF level was obviously related to liver and cardiac iron deposition (MRI T2(*)) r and P value were -0.284, 0.003 and -0.374, 0.000 respectively. In 108 cases regular transfusion and chelation were delayed due to financial problem. The late and insufficient dosage administered and irregular chelation caused the higher SF level and the severe iron deposition., Conclusion: The survival status of β thalassemia major in China is worrisome. Majority of them had not received regular transfusion and chelation. Liver and cardiac iron deposition occur early and had a high incidence.

Objective: To assess the value of magnetic resonance imaging T2* tests in the detection of myocardial and liver iron overload in patients with β-thalassemia major (β-TM)., Methods: From 2010 to 2011, 28 β-TM patients over 10 years old under blood transfusion therapy and chelation care with serum ferritin (SF)>1000 µg/L underwent myocardial and liver MRI T2* tests on a voluntary basis. The results were analyzed in relation with age, SF, and left ventricular ejection fraction (LVEF)., Results: Fourteen out of the 28 cases (50%) were found to have myocardial iron overload, including 7 severe cases, 2 moderate cases, and 5 mild cases. All the 28 cases had liver iron overload, including 2 mild cases, 7 moderate cases, and 19 severe cases. Two out of the 28 cases had lowered LVEF (7.14%), and one of them had severe myocardial iron overload. There was a negative correlation between myocardial MRI T2* and SF (r=-0.479, P=0.01). Myocardial MRI T2* was positively correlated with liver MRI T2* (r=0.378, P=0.047). Age was not significantly correlated with SF, LVEF, or liver MRI T2*., Conclusion: Magnetic resonance imaging (T2*) detection is an effective and non-invasive means for detecting myocardial and liver iron overload in patients with β-thalassemia major receiving blood transfusion. T2* combined with SF is the main diagnostic indicator to assess iron overload in the vital organs.

Objective: To investigate the effect of human cytomegalovirus (HCMV) infection on T lymphocyte subsets in children with β-thalassemia major (TM) during the initial 6 months after allogeneic hematopoietic stem cell transplantation (Allo-HSCT)., Methods: From January, 2010 to January, 2011, 35 children with TM underwent Allo-HSCT. Peripheral blood samples were obtained from the children 6 month after the transplantation to examine the changes of T lymphocytes subsets in relation to HCMV seropositivity., Results: Thirteen children were found seropositive and 22 were seronegative for HCMV. The HCMV-seropositive children had a higher CD8⁺ cell percentage but a lower CD4⁺ cell percentage than those without HCMV infection. Compared with those seronegative for HCMV, the children with HCMV seropositivity showed increased percentages of CD8⁺ cells and CD8⁺CD28⁻ cells with a decreased percentage of CD8⁺CD28⁺ cells. A positive linear correlation was found between the percentages of CD8⁺CD28⁻ cells and CD8⁺ cells., Conclusion: HCMV infection can lead to the accumulation of CD8⁺CD28 cells to cause increased CD8⁺ T cells in the peripheral blood in TM children after Allo-HSCT. The percentages of CD8⁺CD28⁻ cells has a positive linear correlation to that of CD8⁺ cells.

Objective: To investigate the effects of different doses of antithymocyte globubin-fresenius (ATG-F) for allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with beta-thalassemia Major., Methods: Sixty-four children with beta-thalassemia major undergoing allo-HSCT were divided into two equal groups to receive ATG-F pretreatments at high (30 mg/kg) or low (15 mg/kg) doses as part of the conditioning regimen including mainly cyclophosphamide, busulfan, fludarabine, and thiotepa. The outcomes of the patients were compared between the two groups., Results: No obvious difference were noted in the time to leukocyte and platelet engraftment between the two groups. The incidence of grade II-IV acute graft-versus-host disease (aGVHD) appeared to be higher in the low-dose group than in the high-dose group (12.5% vs 9.4%). The incidence of grade III-IV aGVHD was also higher in the low dose group (12.5% vs 6.3%), but the difference was not statistically significant. Application of high-dose ATG-F was associated with a higher rate of probable and possible fungal infection (P<0.05)., Conclusion: The two doses of ATG-F is feasible as a part of the conditioning regimen for allo-HSCT in children with beta-thalassemia major.