Obstetrical correlates and perinatal consequences of neonatal hypoglycemia in term infants.

OBJECTIVE: To determine independent perinatal and intrapartum factors associated with neonatal hypoglycemia. METHOD: Of singleton pregnancies delivered at term in 2013; 318 (3.8%) neonates diagnosed with hypoglycemia were compared to 7955 (96.2%) neonate controls with regression analysis. RESULTS: Regression analysis showed that independent prenatal factors were multiparity (odds-ratio [OR] = 1.61), gestational age (OR = 0.68), gestational diabetes (OR = 0.22), macrosomia (OR = 4.87), small for gestational age neonate [SGA] (OR = 6.83) and admission cervical dilation (OR = 0.79). For intrapartum factors, only cesarean section (OR = 1.57) and last cervical dilation (OR = 0.92) were independently significantly associated with neonatal hypoglycemia. For biologically plausible risk factors, independent factors were cesarean section (OR = 4.18), gentamycin/clindamycin in labor (OR = 5.35), gestational age (OR = 0.59) and macrosomia (OR = 5.62). Mothers of babies with neonatal hypoglycemia had more blood loss and longer hospital stays, while neonates with hypoglycemia had worse umbilical cord gases, more neonatal hypoxic conditions, neonatal morbidities and NICU admissions. CONCLUSION: Diabetes was protective of neonatal hypoglycemia, which may be explained by optimum maternal glucose management; nevertheless macrosomia was independently predictive of neonatal hypoglycemia. Cesarean section and decreasing gestational age were the most consistent independent risk factors followed by treatment for chorioamnionitis and SGA. Further studies to evaluate these observations and develop preventive strategies are warranted.

Phase measurement for accurate mapping of chemical bonds in acentric space groups.

Although the electron density is fundamental to the study of chemical bonding and density-functional theory, it cannot be accurately mapped experimentally for the important class of crystals lacking inversion symmetry, since structure factor phase information is normally inaccessible. We report the combination of x-ray and electron diffraction experiments for the determination of the electron density in acentric AlN, using multiple-scattering effects in convergent-beam electron diffraction to obtain sensitivity to structure factor phases, and describe a new error metric and weighting scheme for multipole refinement using combined measurements of structure factor magnitudes and phases.

Altered major histocompatibility complex class II peptide loading in H2-O-deficient mice.

The biosynthesis of MHC class II/peptide complexes involves classical, cell surface MHC products as well as the intracellular component H2-M, required for the removal of invariant chain-derived CLIP and for peptide loading. The function of another intracellular class II heterodimer, H2-O, is the matter of some controversy. The physical association of H2-O with H2-M and co-localization in class II+ vesicles suggest a related function in peptide exchange. Furthermore, the distinctive thymic distribution of H2-O raises the possibility of a specialized role in T cell thymic selection. To investigate the role of H2-O in vivo we generated mice carrying a targeted disruption in the H2-Oa gene. No evidence was obtained for a defect in removal of CLIP. However, the array of endogenous peptides bound by class II was altered and a defect in antigen presentation through H2-A to T cells was seen on the 129/Sv/ C57BL/6 mixed strain background but not in 129/Sv pure strain mice. Furthermore, H2-O-null mice showed enhanced selection of CD4+ single positive thymocytes. The findings indicate that H2-O interacts with H2-M in peptide editing but that the genetic background in which H2-O deficiency is manifest is also important. Overall, the experiments indicate that H2-O/HLA-DO should be regarded as neither up-regulating nor down-regulating the DM-dependent release of CLIP, but as a modulator of peptide editing, determining the presenting cell type specific peptide profile able to retain stability in the class II groove.

Diet and feeding behaviour of kloss gibbons on Siberut Island, Indonesia.

Kloss gibbons are the same size and live in the same type of habitat as several other gibbon species, and consequently its diet would be expected to be similar to its closely related congeners. The diet is described in terms of the weight of food items, faecal remains, and time devoted to different foods. Aspects of feeding behaviour are then examined, such as changes in food choice through the day, the relationship between fruit size to feeding bouts and feeding rates, and the effect of forest type quality on ranging. A comparison is made between gibbon species. The diet of Kloss gibbons appears to differ from that of other gibbons in that it contained no tree leaves, and arthropods were a major part of the diet. Possible reasons for this are discussed.