A 1H NMR comparative study of human adult and fetal hemoglobins

AbstractThe affinities of the individual subunits in human adult and fetal hemoglobins to azide ion have been determined from the combined analysis of NMR and optical titration data. Structural and functional non-equivalence of the constituent subunits, i.e. α and β subunits in human adult hemoglobin and α and γ subunits in human fetal hemoglobin, has been confirmed. The function of the α subunits, which are common to both hemoglobins, is essentially identical in these hemoglobins and, in spite of the substitutions of 39 amino acid residues between β and γ subunits, they exhibit similar azide ion affinities. The present study also demonstrates that the NMR spectral comparison between the two proteins provides signal assignments to the individual subunits in intact tetramer

Perinatal outcome in singletons after modified natural cycle IVF and standard IVF with ovarian stimulation

Objective: Singletons born after IVF treatment are at risk for adverse pregnancy outcome, the cause of which is unknown. The aim of the present study was to investigate the influence of ovarian stimulation on perinatal outcome. Study design: In this single-centre retrospective study, perinatal outcome of singleton pregnancies resulting from IVF treatment with (n = 106) and without ovarian stimulation (n = 84) were compared. For IVF without ovarian stimulation, a modified natural cycle protocol was used. Results: No differences were found in pregnancy duration, proportion of prematurity and proportion of low birth weight. Mean birth weight of modified natural cycle vs standard IVF singletons was 3485 (+/-527) vs 3218 (+/-670) g; P = 0.003. After adjustment for prognostic factors by linear regression analysis, the difference in birth weight remaining was 134 g; P = 0.045. Conclusions: Birth weights of modified natural cycle IVF singletons found in this study are higher than standard IVF singletons, suggesting that ovarian stimulation may be a causative factor in the occurrence of low birth weight in standard IVF. (C) 2009 Elsevier Ireland Ltd. All rights reserved

Early enteral tube feeding in optimizing treatment of hyperemesis gravidarum:the Maternal and Offspring outcomes after Treatment of HyperEmesis by Refeeding (MOTHER) randomized controlled trial

Background: Hyperemesis gravidarum (HG) leads to dehydration, poor nutritional intake, and weight loss. HG has been associated with adverse pregnancy outcomes such as low birth weight. Information about the potential effectiveness of treatments for HG is limited.Objective: We hypothesized that in women with HG, early enteral tube feeding in addition to standard care improves birth weight.Design: We performed a multicenter, open-label randomized controlled trial [Maternal and Offspring outcomes after Treatment of HyperEmesis by Refeeding (MOTHER)] in 19 hospitals in the Netherlands. A total of 116 women hospitalized for HG between 5 and 20 wk of gestation were randomly allocated to enteral tube feeding for ≥7 d in addition to standard care with intravenous rehydration and antiemetic treatment or to standard care alone. Women were encouraged to continue tube feeding at home. On the basis of our power calculation, a sample size of 120 women was anticipated. Analyses were performed according to the intention-to-treat principle.Results: Between October 2014 and March 2016 we randomly allocated 59 women to enteral tube feeding and 57 women to standard care. The mean ± SD birth weight was 3160 ± 770 g in the enteral tube feeding group compared with 3200 ± 680 g in the standard care group (mean difference: -40 g, 95% CI: -230, 310 g). Secondary outcomes, including maternal weight gain, duration of hospital stay, readmission rate, nausea and vomiting symptoms, decrease in quality of life, psychological distress, prematurity, and small-for-gestational-age, also were comparable. Of the women allocated to enteral tube feeding, 28 (47%) were treated according to protocol. Enteral tube feeding was discontinued within 7 d of placement in the remaining women, primarily because of its adverse effects (34%).Conclusions: In women with HG, early enteral tube feeding does not improve birth weight or secondary outcomes. Many women discontinued tube feeding because of discomfort, suggesting that it is poorly tolerated as an early routine treatment of HG. This trial was registered at www.trialregister.nl as NTR419