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Objective: Dysbiosis of the infant gut microbiota may have long-term health consequences. This study aimed to determine the impact of maternal intrapartum antibiotic prophylaxis (IAP) on infant gut microbiota, and to explore whether breastfeeding modifies these effects.Design: Prospective pregnancy cohort of Canadian infants born in 2010-2012: the Canadian Healthy Infant Longitudinal Development (CHILD) Study.Setting: General community.Sample: Representative sub-sample of 198 healthy term infants from the CHILD Study.Methods: Maternal IAP exposures and birth method were documented from hospital records and breastfeeding was reported by mothers. Infant gut microbiota was characterised by Illumina 16S rRNA sequencing of faecal samples at 3 and 12 months.Main Outcome Measures: Infant gut microbiota profiles.Results: In this cohort, 21% of mothers received IAP for Group B Streptococcus prophylaxis or pre-labour rupture of membranes; another 23% received IAP for elective or emergency caesarean section (CS). Infant gut microbiota community structures at 3 months differed significantly with all IAP exposures, and differences persisted to 12 months for infants delivered by emergency CS. Taxon-specific composition also differed, with the genera Bacteroides and Parabacteroides under-represented, and Enterococcus and Clostridium over-represented at 3 months following maternal IAP. Microbiota differences were especially evident following IAP with emergency CS, with some changes (increased Clostridiales and decreased Bacteroidaceae) persisting to 12 months, particularly among non-breastfed infants.Conclusions: Intrapartum antibiotics in caesarean and vaginal delivery are associated with infant gut microbiota dysbiosis, and breastfeeding modifies some of these effects. Further research is warranted to explore the health consequences of these associations.Tweetable Abstract: Maternal #antibiotics during childbirth alter the infant gut #microbiome. [ABSTRACT FROM AUTHOR]

Trans-11 vaccenic acid (VA) is the predominant trans isomer in ruminant fat and a major precursor to the endogenous synthesis of cis9,trans11-conjugated linoleic acid in humans and animals. We have previously shown that 3-wk VA supplementation has a triglyceride (TG)-lowering effect in a rat model of dyslipidemia, obesity, and metabolic syndrome (JCR:LA-cp rats). The objective of this study was to assess the chronic effect (16 wk) of VA on lipid homeostasis in both the liver and intestine in obese JCR:LA-cp rats. Plasma TG (P < 0.001), total cholesterol (P < 0.001), LDL cholesterol (P < 0.01), and nonesterified fatty acid concentrations, as well as the serum haptoglobin concentration, were all lower in obese rats fed the VA diet compared with obese controls (P < 0.05). In addition, there was a decrease in the postprandial plasma apolipoprotein (apo)B48 area under the curve (P < 0.05) for VA-treated obese rats compared with obese controls. The hepatic TG concentration and the relative abundance of fatty acid synthase and acetyl-CoA carboxylase proteins were all lower (P < 0.05) in the VA-treated group compared with obese controls. Following acute gastrointestinal infusion of a VA-triolein emulsion in obese rats that had been fed the control diet for 3 wk, the TG concentration was reduced by 40% (P < 0.05) and the number of chylomicron (CM) particles (apoB48) in nascent mesenteric lymph was reduced by 30% (P < 0.01) relative to rats infused with a triolein emulsion alone. In conclusion, chronic VA supplementation significantly improved dyslipidemia in both the food-deprived and postprandial state in JCR:LA-cp rats. The appreciable hypolipidemic benefits of VA may be attributed to a reduction in both intestinal CM and hepatic de novo lipogenesis pathways. [ABSTRACT FROM AUTHOR]

A study was conducted to determine the effect of Acticoattrade mark placed on an infected skin graft on parameters of immunity. Two partial thickness wounds (2cmx4cm) were created on the dorsal midline of Hartley guinea pigs (n=28). Wounds were covered with autologous skin graft and maintained either aseptically (Noninoculated, n=8), inoculated with Staphylococcus aureus (Surgery-Inoculated, n=8) with or without Acticoattrade mark bandage (Surgery-Inoculated-Acticoat, n=6). Five days later, splenocytes and blood were collected to estimate natural killer cell (NK) cytotoxicity, proliferative response to T and B cell mitogens and neutrophil oxidative burst. Animals that did not undergo surgery were included as a nonsurgery control group. [(3)H]-thymidine incorporation in response to a variety of T and B cell mitogens was significantly lower for all groups undergoing surgery compared to the nonsurgery control group (p<0.0001) and no additional effect was observed on this immune measure by applying the Acticoat bandage. The Surgery-Inoculated-Acticoat group exhibited greater NK cytotoxic activity (as assessed as the ability to lyse K562 tumor cells) compared to the Surgery-Inoculated group (p<0.006). The Surgery-Inoculated-Acticoat group had higher neutrophil oxidative burst at 5min post stimulation, but was not different from controls after 15min. In conclusion, the application of an Acticoattrade mark bandage to an inoculated surgery wound did not alter the low cell-mediated immune response that followed surgery, but appeared to increase parameters (NK cytotoxic activity and neutrophil function) of innate immunity. [ABSTRACT FROM AUTHOR]

This study evaluated preterm infants of less than 2.3 kg birth weight fed commercial formula (Preemie SMA[sup ®]) devoid of arachidonic acid (AA) and docosahexaenoic acid (DHA) and compared this control group with similar infant groups fed one of three formulas containing a range of 0.32-1.1% AA and 0.24-0.75% DHA in the fat component of the formula. An analogous group of infants fed on their mothers' breast milk and a breast milk fortifier was also studied. Individual lipoprotein fractions were isolated from blood samples collected at 12 d of age and after a further 4 wk of feeding. The fatty acid content of individual lipid components, isolated from each lipoprotein fraction was quantitatively determined in order to identify change in marker pools of essential fatty acid. The high density lipoproteins (HDL) and low density lipoproteins (LDL) phospholipid and cholesterol ester fractions contain most of the AA and DHA found in the lipoprotein fractions (total of 0.49% and 0.35%, respectively). Infants fed a formula without AA and DHA showed a reduction in AA level in the phospholipid fraction of all lipoproteins and in the HDL and LDL cholesterol ester fraction. A reduced level of DHA was also observed primarily in the lipoprotein phospholipid fraction in comparison with infants fed breast milk or infant formula containing AA and DHA. Supplementing infant formula with increasing levels of AA and DHA produced a clear dose response in the level of AA found in the HDL and LDL phospholipid fraction. From comparison of the fatty acid levels present in the lipoproteins it appears that a formula level of 0.49% AA and 0.35% DHA provides sufficient levels of these fatty acids to achieve a similar fatty acid content to that of infants fed breast milk for the major lipoprotein fractions examined. [ABSTRACT FROM AUTHOR]