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Very preterm infants are vulnerable to deficiency in DHA. In a longitudinal study, 10 mothers who delivered ≤29 wk gestation and planned to breast-feed received DHA (1200 mg/d) until 36 wk after conception. The plasma DHA status was assessed in their 12 infants (including 2 pairs of twins) from birth to d 49. Fatty acid profiles were measured weekly in breast milk, and in plasma of mothers and infants at baseline and at d15 and 49. Plasma and breast milk fatty acid concentrations in the DHA-supplemented group at d 49 were compared with a reference group of very preterm infants (n = 24, including triplets) whose mothers (n = 22) did not receive DHA during lactation. The infants' plasma DHA concentration tended to be greater in the DHA group than in the reference group (P = 0.10) and was greater when expressed as a percentage of total fatty acids (P = 0.009). At d 49, maternal milk DHA in the DHA group (1.92 ± 1.10 mmol/L) was ~12 times higher than in the reference group (0.15 ± 0.27 mmol/L) (P < 0.001). The amount of DHA provided to the infants increased from wk 1 through wk 7 in the DHA group (P < 0.001). Although enteral intake at wk 7 did not differ between the DHA group [119 ± 51 mL/(kg·d)] and the reference group [113 ± 66 mL/(kg·d)], DHA group infants received 55 ± 38 mg/(kg·d) of DHA, and the reference group infants received 7 ± 11 mg/(kg·d) (P < 0.001). Early supplementation with DHA to lactating mothers with low dietary DHA intake successfully increased the plasma DHA status in very preterm infants.

This paper describes the preparation, characterization and permeation properties of polyimide BTDA-AAPTMI (Matrimid 5218) and co-polyimide BTDA-TDI/MDI (P84) dense polymer films containing aliphatic hyperbranched polyesters, Boltorn (H40). The H40 are dispersed in the polymers at various concentrations. For Matrimid–H40 1.0 wt% membrane the nitrogen permeability increases but with significant loss in selectivity, while at higher H40 concentrations (5.0 and 10.0 wt%) the permeability becomes lower than of the pure polymer and the selectivity generally stays constant. The dispersion of various concentrations of H40 (1.0, 5.0 and 10.0 wt%) in P84 membranes decreases gas permeability in comparison to pure P84, while the selectivity generally stays constant.

PPO (poly(2,6-dimethyl-1,4-phenylene oxide)) is a well-known membrane material showing good gas separation properties. The incorporation of nanoparticles can enhance or deteriorate the performance of composite membranes, sometimes depending only on the way of the composite preparation. We have modified the PPO polymer with C60 fullerenes up to a content of 2 wt %. Previous investigations showed a strong dependence of permeability on whether the C60 is simply dispersed in the polymer or chemically bonded to the polymer chains. Free volume effects were suggested as an explanation but not experimentally confirmed. Here, we present free volume studies by positron annihilation lifetime spectroscopy. An additional long positron lifetime shows the increased free volume of composite samples, while the high electron affinity of C60 helps to indicate the homogeneity of the samples. Combining the presented results with permeability measurements refines the understanding of this promising membrane material.

This paper describes the preparation, characterization and the permeation properties of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) dense polymer films containing aliphatic hyperbranched polyesters, Boltorn (H20, H30, and H40). The Boltorn are dispersed in PPO at various concentrations. The gas permeability results were very different between low and high concentration of Boltorn. The gas permeability of PPO with 1.0 wt % of Boltorn is 2−3 times higher than the pure polymer, while at higher concentration (9.1 wt %) of Boltorn the permeability becomes almost 50% of the pure polymer. The gas pair selectivity, however, stays constant. The increase in permeability at low concentration of Boltorn is due to the increase of the free volume, probably due to hydrogen bonds between Boltorn and the oxygen of PPO backbone. The decreased permeability of PPO containing higher concentration of Boltorn (9.1 wt %) is due to two reasons: decrease in free volume as determined by PALS as well as phase separation. The hyperbranced polyesters form aggregates that migrate to the top surface of the membrane.

This paper describes the preparation, characterization, and the permeation properties of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) dense polymer films containing fullerenes (C60). The C60 are either dispersed or covalently bonded to PPO at various concentrations. The gas permeability results are very different between covalently bonded and dispersed PPO−C60. The gas permeability of PPO−C60 bonded increases up to 80% with increasing fullerene concentration. The gas pair selectivity, however, stays constant. This behavior is probably due to stiffening of the polymer structure and increase of free volume. The gas permeability through the PPO−C60 dispersed decreases in comparison to pure PPO. This reduction is due to C60 clustering in the polymer. The clusters seem to induce polymer crystallinity, and they are probably aligned along the film plane, creating an extra barrier for gas permeation.

Hemangiomas of infancy are benign vascular tumors frequently encountered in pediatrics. Medical treatment (corticosteroids, interferon, chemotherapy, embolization and radiation) in high-risk hemangioma cases could greatly benefit from the addition of new and safer therapies. The rapid growth of hemangiomas during the proliferative phase occurs secondary to a process of local uncontrolled angiogenesis, involving potent mediators such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). We hypothesize that omega-3 fatty acids, naturally occurring nutrients of proven health benefit to infants, could become an alternative or an adjuvant treatment for hemangiomas, by slowing down their rapid proliferation phase through anti-angiogenic and anti-tumoral effects. Suggested mechanisms of action of omega-3 fatty acids include the downregulation of VEGF and bFGF, and the suppression of pro-angiogenic eicosanoids such as cylooxygenase-2. In this article, we review recent animal and human studies using dietary omega-3 fatty acids supplements, alone or in conjunction with chemotherapy, for the treatment of a variety of tumors dependent on angiogenesis for growth. Available murine hemangioma models offer the opportunity to determine optimal omega-3 fatty acid dose, while taking in account related immunohistochemical markers, clinical outcome and secondary effects, before planning clinical trials. Lessons learned in hemangiomas of infancy may have a broad impact in understanding the phenomenon of dysregulated angiogenesis in cancer research.

In this work, we report superior mass transport properties of polymers prepared by the covalent coupling of supermolecular carbon cages (e.g., fullerenes, bucky balls) to a poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) polymer. Dispersing the bucky balls into the polymer reduces gas permeability, whereas covalent bonding enhances permeability up to 80% in comparison to the pure PPO. Gas pair selectivity, however, is not compromised and stays constant.

Im Rahmen von Untersuchungen zur Bromierung von Propiophenon wurde eine infrarotspektrophotometrische Methode zur Bestimmung von α-Brompropiophenon in Gegenwart von α-Dibrompropiophenon und Propiophenon entwickelt. Die Methode ist genau und schnell. α-Brompropiophenon und α-Dibrompropiophenon wurden erstmalig durch ihre Infrarotabsorptionsspektren chatakterisiert.

Bei der Synthese vonγ-Acetopropanol durch Hydrierung von Methylfuran in acetonischer Losung wurden unverandertes Methylfuran bromatometrisch und Aceton durch Oximierung bestimmt. Dabei ergab sich, das noch eine dritte Komponente vorhanden war, die als Methyltetrahydrofuran erkannt wurde. Mit Hilfe der Gas-Chromatographie konnten alle drei Verbindungen nebeneinander bestimmt werden.

The cerebral protein metabolism (32 P incorporation into cerebral proteins, total RNA and DNA, cerebral free aminoacid content) was investigated in 90 newborn rats of either sex, injected daily with Nialamide or saline, and killed 7, 14, 21 and 28 days after birth. The results revealed a significant decrease of 32 P-in-corporation into cerebral proteins, RNA and DNA, especially in 7 and 14-day-old rats. Cerebral free aminoacid content (glutamic acid, alpha-alanine, leuccine, valine and lysine) decrease significantly in 7 and 14-day-old rats. The modifications of protein metabolism and total nucleic acids in Nialamide - treated newborn rats might be attributed to the direct action of MAO inhibitors on the cerebral protein metabolism or to an indirect action via the adrenal cortex. The authors discuss the possible biochemical codification of behavior.

(1) In 1-day old rats, cerebral RNA and DNA synthesis exhibits a continuous increase with a peak between 7 and 14 days after birth. (2) Hydrocortisone induces a significant inhibition of cerebral RNA and DNA synthesis, noticeable in 7-day old rats. (3) In ACTH-treated newborn rats, RNA and DNA synthesis is greatly increased in 7- and 14-day old rats. (4) Aldosterone elicits an enhancement of brain nucleic acid synthesis, more marked in 7- and 14-day old rats. (5) Thyroxine administration induces a great stimulation of cerebral RNA and DNA synthesis, greatest at 7 and 14 days after birth. (6) The results confirm the important, even decisive, role of endocrine secretions during the early postnatal life, as far as subsequent individual development is concerned.