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Objective To study the rate of mother-to-child transmission (MTCT) on HIV-1. Methods All local residents from 8 townships in a region were screened for mothers who had a history of only one blood transfusion and 63 were found HIV-1 positive. A further study on these HIV-1 positive mothers and their children was conducted with the emphasis on the date of receiving blood transfusion, date and type of nationality, history regarding breastfeeding and so on. Sera specimens from 84 children born from 63 HIV-1 positive mothers were screened, using ELISA for HIV-1 antibody, and positive specimens were confirmed by Western-blot. Results The rate of MTCT was 32.1% (27/84) for children with all risk factors related to MTCT. Another 36.8% (7/19) were related to factors on intrauterine, intrapartum and breastfeeding, 35.7% (5/14) to intrapartum and breastfeeding factors, 14.3% (2/14) to intrauterine and intrapartum factors, 37.9% (11/29) to breastfeeding factor alone. By group combination analysis, the MTCT rate was 36.9% (24/65) with breastfeeding, 11.8% (2/17) with artificial feeding, and the former was significantly higher than the latter. Conclusion HIV-1 MTCT rate among mothers caused by a single blood transfusion varied with different risk factors. Breastfeeding played an important role in MTCT, appeared in our study.
RESUMO
OBJECTIVE: To evaluate in vitro microleakage of class V restorations using two self-etching primers with a flowable resin or hybrid resins. METHODS: Forty human molars were divided into 3 groups according to axial surfaces. Each group was randomly assigned to 2 subgroups (n=20) with either butt-joint or the beveled preparations. Class V preparations were cut in cemento-enamel junction. Groups A, B, C were respectively restored with CLB2/Clearfil AP-X, APMB/FHC-Merz or APMB/Liquicoat. Half specimens of each subgroup were thermocycled 2 500 times. After staining, dye penetration was evaluated in the ordinal scale at 40Xmagnifications for occlusal and the gingival margins. The wall adaptation of the randomly selected specimens was analyzed with a SEM on replicas of the sectioned teeth. RESULTS: None of bond systems in this study prevented the microleakge. The restorations with the bur-beveled preparations leaked the same as those with the butt joint preparations (P>0.05). The thermocycled specimens and the non-thermocycled specimens leaked similarly (P>0.05). The flowable resin-liqucoat leaked significantly more than hybrid resin in dentinal margins (P<0.05). CONCLUSION: The self-etching primers can not reduce the microleakge in the dentin-restoration interfaces. The flowable resin leak more than the hybrid resin in dentin-restoration interfaces. The bur- beveled preparations do not significantly reduce the microleakage in class V resin restorations bonded with self-etching primers.