Breastfeeding Progression in Preterm Infants Is Influenced by Factors in Infants,Mothers and Clinical Practice: The Results of a National Cohort Study with High Breastfeeding Initiation Rates

Background and Aim

Many preterm infants are not capable of exclusive breastfeeding from birth. To guide mothers in breastfeeding, it is important to know when preterm infants can initiate breastfeeding and progress. The aim was to analyse postmenstrual age (PMA) at breastfeeding milestones in different preterm gestational age (GA) groups, to describe rates of breastfeeding duration at pre-defined times, as well as analyse factors associated with PMA at the establishment of exclusive breastfeeding.

Methods

The study was part of a prospective survey of a national Danish cohort of preterm infants based on questionnaires and structured telephone interviews, including 1,221 mothers and their 1,488 preterm infants with GA of 24–36 weeks.

Results

Of the preterm infants, 99% initiated breastfeeding and 68% were discharged exclusively breastfed. Breastfeeding milestones were generally reached at different PMAs for different GA groups, but preterm infants were able to initiate breastfeeding at early times, with some delay in infants less than GA 32 weeks. Very preterm infants had lowest mean PMA (35.5 weeks) at first complete breastfeed, and moderate preterm infants had lowest mean PMA at the establishment of exclusive breastfeeding (36.4 weeks). Admitting mothers to the NICU together with the infant and minimising the use of a pacifier during breastfeeding transition were associated with 1.6 (95% CI 0.4–2.8) and 1.2 days (95% CI 0.1–2.3) earlier establishment of exclusive breastfeeding respectively. Infants that were small for gestational age were associated with 5.6 days (95% CI 4.1–7.0) later establishment of exclusive breastfeeding.

Conclusion

Breastfeeding competence is not developed at a fixed PMA, but is influenced by multiple factors in infants, mothers and clinical practice. Admitting mothers together with their infants to the NICU and minimising the use of pacifiers may contribute to earlier establishment of exclusive breastfeeding.     

PRC1 and PRC2 are not required for targeting of H2A.Z to developmental genes in embryonic stem cells

The essential histone variant H2A.Z localises to both active and silent chromatin sites. In embryonic stem cells (ESCs), H2A.Z is also reported to co-localise with polycomb repressive complex 2 (PRC2) at developmentally silenced genes. The mechanism of H2A.Z targeting is not clear, but a role for the PRC2 component Suz12 has been suggested. Given this association, we wished to determine if polycomb functionally directs H2A.Z incorporation in ESCs. We demonstrate that the PRC1 component Ring1B interacts with multiple complexes in ESCs. Moreover, we show that although the genomic distribution of H2A.Z co-localises with PRC2, Ring1B and with the presence of CpG islands, H2A.Z still blankets polycomb target loci in the absence of Suz12, Eed (PRC2) or Ring1B (PRC1). Therefore we conclude that H2A.Z accumulates at developmentally silenced genes in ESCs in a polycomb independent manner.     

Consistent Condom Use Increases the Regression Rate of Cervical Intraepithelial Neoplasia 2–3

Objective

Cervical intraepithelial neoplasia grades 2-3 (CIN2-3) are usually treated by cone excision, although only 30% progress to cancer and 6–50% regress spontaneously. The aim of this study was to examine the influence of clinical factors like smoking habits, number of lifetime sexual partners, age at first sexual intercourse, sexual activity span and hormonal versus non-hormonal contraception type on the regression rate of CIN2-3.

Methods

In this prospective population-based cohort study 170 women aged 25–40 with abnormal cytology and colposcopy-directed biopsies showing first time onset CIN2-3 were consecutively included. The interval between biopsy and cone excision was standardized to minimum 12 weeks. Regression was defined as ≤CIN1 in the cone biopsy.

Results

The regression rate was 22%. Consistent condom use, defined as those women whose partners used condoms for all instances of sexual intercourse, was infrequent (n = 20, 12%). In univariate analysis consistent condom use, hormonal contraception and age at first sexual intercourse significantly predicted regression. In a multivariate analysis only consistent condom use remained as an independent predictor of regression (regression rate 55%, p = 0.001, hazard ratio = 4.4).

Conclusion

Consistent condom use between punch biopsy and cone excision in first-time onset CIN2-3 patients significantly increases the regression rate.     

High-glycemic index carbohydrates abrogate the antiobesity effect of fish oil in mice

Fish oil rich in n-3 polyunsaturated fatty acids is known to attenuate diet-induced obesity and adipose tissue inflammation in rodents. Here we aimed to investigate whether different carbohydrate sources modulated the antiobesity effects of fish oil. By feeding C57BL/6J mice isocaloric high-fat diets enriched with fish oil for 6 wk, we show that increasing amounts of sucrose in the diets dose-dependently increased energy efficiency and white adipose tissue (WAT) mass. Mice receiving fructose had about 50% less WAT mass than mice fed a high fish oil diet supplemented with either glucose or sucrose, indicating that the glucose moiety of sucrose was responsible for the obesity-promoting effect of sucrose. To investigate whether the obesogenic effect of sucrose and glucose was related to stimulation of insulin secretion, we combined fish oil with high and low glycemic index (GI) starches. Mice receiving the fish oil diet containing the low-GI starch had significantly less WAT than mice fed high-GI starch. Moreover, inhibition of insulin secretion by administration of nifedipine significantly reduced WAT mass in mice fed a high-fish oil diet in combination with sucrose. Our data show that the macronutrient composition of the diet modulates the effects of fish oil. Fish oil combined with sucrose, glucose, or high-GI starch promotes obesity, and the reported anti-inflammatory actions of fish oil are abrogated. In conclusion, our data indicate that glycemic control of insulin secretion modulates metabolic effects of fish oil by demonstrating that high-GI carbohydrates attenuate the antiobesity effects of fish oil.     

Phytoplankton chemotaxonomy in waters around the Svalbard archipelago reveals high amounts of Chl b and presence of gyroxanthin-diester

Phytoplankton pigment signatures from a cruise in 2005 are herein presented and used as a chemotaxonomic tool for phytoplankton diversity in the Svalbard marine archipelago. Studies from these waters have until recently reported only a few groups of phytoplankton, and while this paper is the first to show that the diversity around Svalbard includes all major phytoplankton pigment groups, the results are seen in relation to other similar studies from the Arctic. We present two potentially important marker pigments: prasinoxanthin, originating from prasinophytes, and gyroxanthin-diester, possibly originating from the temperate- and bloom-forming coccolithophore Emiliania huxleyi. Pigment identification by HPLC revealed a significant amount of Chlorophyll b-containing chlorophyceae, euglenophyceae and prasinophyceae. Prasinoxanthin was present at 50% of the examined stations, typically at Chl a maximum (15–25 m depth), in both Atlantic and Arctic water masses. Gyroxanthin-diester, in contrast to prasinoxanthin, was found only in Atlantic water masses and at low concentrations. Our data may be important for the identification and verification of remotely sensed images of different pigment groups of phytoplankton and their corresponding biomass, typically estimated from Chl a. Remotely sensed presence of coccoliths, indicating E. huxleyi at sea surface, is discussed in relation to water masses and pigment signatures at sea surface and Chl a maximum depths.     

Embryo-specific Proteins in <Emphasis Type="Italic">Cyclamen persicum</Emphasis> Analyzed with 2-D DIGE

Somatic embryogenesis can be used to produce artificial seeds of Cyclamen persicum, one of the most important ornamental plants for the European market, both as a potted plant in northern Europe and a bedding plant in the cool winters in southern Europe. The aim of this study was to obtain new insights into the molecular biology of somatic embryogenesis, which in turn can be useful for the improvement of tissue culture methodology. Total proteins were characterized from two isogenic cell lines of Cyclamen persicum, one that was embryogenic and one that never has shown any embryogenic capacity. The extracted proteins were separated by two-dimensional differential gel electrophoresis (2-D DIGE) and selected proteins were treated using the ETTAN Dalt Spot Handling Workstation. Protein identification was performed using MALDI-TOF-MS. More than 1200 Cyclamen proteins were detected; 943 proteins were common to both lines. The different protein patterns of the embryogenic and non-embryogenic cell lines were obvious: One hundred eight proteins were more abundant in the embryogenic cells, and 97 proteins in the non-embryogenic cells. Among the differentially expressed proteins, 128 were identified. MALDI-TOF-MS analysis enabled 27 spots to be proposed as candidates for embryo-specific proteins, as they were unique to the embryogenic cell line. The proteins identified are involved in a variety of cellular processes, including cell proliferation, protein processing, signal transduction, stress response, metabolism, and energy state, but the majority are involved in protein processing and metabolism. The main functions of the putative embryo-specific proteins have been discussed in proportion to their role in the somatic embryogenesis process. Electronic Supplementary Material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. R. Lyngved and J. Renaut contributed equally to this work.     

Direct and indirect mate choice on leks

Indirect mate choice is any behavior that restricts the individual's set of potential mates without discrimination of mate attributes directly, for example, by having preferences about where to mate. We analyzed a 14-year data set from great snipe (Gallinago media) leks for evidence of indirect mate choice based on relative and absolute position of lek territories. We found little or no effect of the centrality of territories on mating and no between-year consistency in the spatial distribution of matings within leks. Instead, the probability of matings occurring at a particular site increased if the current territory owner had mated the previous year. Furthermore, individual females returned in later seasons to mate with the same male as previously rather than at the same site. Previous work found that male interactions and dominance do not control matings and that females are very choosy about which territory they mate in. Here we show that this is because of the male occupying the territory rather than its position. We therefore conclude that direct female mate choice is the main behavioral process affecting variation in mating success among great snipe males, unlike in some lekking mammals where male competition and/or indirect mate choice appears more important.