The efficacy and safety of maternal tenofovir disoproxil fumarate (TDF) in reducing mother‐to‐infant hepatitis B virus (HBV) transmissions is not clearly understood. We conducted a prospective, ...multicenter trial and enrolled 118 hepatitis B surface antigen (HBsAg)– and hepatitis B e antigen–positive pregnant women with HBV DNA ≥7.5 log10 IU/mL. The mothers received no medication (control group, n = 56, HBV DNA 8.22 ± 0.39 log10 IU/mL) or TDF 300 mg daily (TDF group, n = 62, HBV DNA 8.18 ± 0.47 log10 IU/mL) from 30‐32 weeks of gestation until 1 month postpartum. Primary outcome was infant HBsAg at 6 months old. At delivery, the TDF group had lower maternal HBV DNA levels (4.29 ± 0.93 versus 8.10 ± 0.56 log10 IU/mL, P < 0.0001). Of the 121/123 newborns, the TDF group had lower rates of HBV DNA positivity at birth (6.15% versus 31.48%, P = 0.0003) and HBsAg positivity at 6 months old (1.54% versus 10.71%, P = 0.0481). Multivariate analysis revealed that the TDF group had lower risk (odds ratio = 0.10, P = 0.0434) and amniocentesis was associated with higher risk (odds ratio 6.82, P = 0.0220) of infant HBsAg positivity. The TDF group had less incidence of maternal alanine aminotransferase (ALT) levels above two times the upper limit of normal for ≥3 months (3.23% versus 14.29%, P = 0.0455), a lesser extent of postpartum elevations of ALT (P = 0.007), and a lower rate of ALT over five times the upper limit of normal (1.64% versus 14.29%, P = 0.0135) at 2 months postpartum. Maternal creatinine and creatinine kinase levels, rates of congenital anomaly, premature birth, and growth parameters in infants were comparable in both groups. At 12 months, one TDF‐group child newly developed HBsAg positivity, presumably due to postnatal infection and inefficient humoral responses to vaccines. Conclusions: Treatment with TDF for highly viremic mothers decreased infant HBV DNA at birth and infant HBsAg positivity at 6 months and ameliorated maternal ALT elevations. (Hepatology 2015;62:375–386
Summary
Background
Maternal anti‐viral treatment prevents mother‐to‐infant transmission of hepatitis B virus (HBV), but the role of neonatal viremia on subsequent HBV infection is not clear.
Aims
To ...investigate the effect of maternal anti‐viral treatment on neonatal serum HBV DNA and hepatitis B surface antigen (HBsAg) in infants born to highly viremic mothers and the roles of neonatal markers in predicting chronic HBV infection in children.
Methods
Serum HBV DNA and HBsAg were tested in children. Of the 201 pregnant mothers, 110 received tenofovir during the third trimester. Chronic infection in children was defined by HBsAg seropositivity at 6 or 12 months lasting more than 6 months.
Results
The maternal HBV viral loads from baseline to delivery were 8.25 ± 0.48 to 4.29 ± 0.98 log10 IU/mL; and 8.29 ± 0.49 to 8.12 ± 0.68 log10 IU/mL in the tenofovir and control group respectively. Of the 208 children, those in the tenofovir group had a lower rate of neonatal HBV DNA seropositivity at birth (5.22% vs 30.11%, P < 0.0001) and HBsAg seropositivity at 6 months (1.74% vs 11.83%, P = 0.003) and 12 months (1.74% vs 10.75%, P = 0.007). In a first multivariate analysis, maternal HBV DNA level at delivery (odds ratio = 1.70, P = 0.0172) and neonatal HBsAg positivity (odds ratio = 19.37, P < 0.0001) were significantly associated with children's chronic HBV infection. In a second model, neonatal HBV DNA positivity was a strong independent influence variable (odds ratio = 61.89, P = 0.0002).
Conclusions
Maternal tenofovir therapy decreased maternal viral load and neonatal viremia. Positive neonatal HBV DNA was highly correlated with chronic HBV infection in children. Clinical Trial Identifier: NCT01312012.
The softening and melting behavior of sinter, pellet and mixed burden was researched through high temperature reaction tests under load simulating traditional blast furnace (T-BF) and oxygen blast ...furnace (OBF) conditions. The results indicated that compared with T-BF, the softening zone of sinter and pellet became wide, but the melting zone became narrow in OBF. The permeabilities of both sinter and pellet were improved in OBF. Under the condition of OBF, the temperature of softening zone of mixed burden was increased by 63 K, but the temperature of melting zone was decreased by 76 K. Therefore, the permeability of material layer was significantly improved. This was mainly caused by the change of the melting behavior of pellet. In addition, the quality of dripping iron in OBF was much better than that of T-BF.
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