Urinary Recovery of Dicyandiamide (DCD) Pulse-Dosed into the Rumen of Non-Lactating Dairy Cows, and the Effects of Applying Urine with DCD to Lysimeters on Nitrous Oxide and Nitrate Leaching in Ireland

Urine excreted by dairy cows is a source of nitrogen (N) to the sward. The N content of urine is high, up to 1000 kg N/ha and is usually in excess of sward requirements. Surplus N is usually lost through a number of pathways including nitrate (NO3-) leaching and nitrous oxide (N2O) emissions. Dicyandiamide (DCD), a nitrification inhibitor, has been shown to reduce NO3- leaching and N2O emissions when applied as a fine particle suspension (FPS) to grazed paddocks. The objectives of the study were to: (1) quantify the recovery of DCD in the urine when DCD was pulse-dosed DCD into the rumen of non-lactating dairy cows; and (2) to examine the effects of urine collected from dairy cows pulse-dosed with DCD on N2O emissions and NO3- leaching using lysimeters

Bovine milk oligosaccharides as anti-adhesives against the respiratory tract pathogen Streptococcus pneumoniae

peer-reviewedStreptococcus pneumoniae is a Gram-positive pathogen, which is regularly found in the upper respiratory tract of healthy individuals. Increased numbers of S. pneumoniae have been observed colonising the upper respiratory tract of children affected by respiratory tract infections. Galβ1-4GlcNAcβ1-3Gal has been previously identified as one of the receptors involved in the adherence and translocation of S. pneumoniae. As this structure is similar to the milk oligosaccharide lacto-N-neoTetraose, many studies have investigated if free milk oligosaccharides can inhibit the adhesion of S. pneumoniae to epithelial cells of the respiratory tract. Here, we demonstrate that bovine oligosaccharides, which were extracted from demineralised whey, using a combination of membrane filtration and chromatography, were capable of reducing S. pneumoniae adhesion to pharynx and lung cells in vitro when tested at physiological concentrations. This study strengthens the potential use of bovine derived milk oligosaccharides as functional ingredients to reduce the incidence of infectious diseases

Oligosaccharides Isolated from MGO™ Manuka Honey Inhibit the Adhesion of Pseudomonas aeruginosa, Escherichia Coli O157:H7 and Staphylococcus Aureus to Human HT-29 cells

peer-reviewedHistorically, honey is known for its anti-bacterial and anti-fungal activities and its use for treatment of wound infections. Although this practice has been in place for millennia, little information exists regarding which manuka honey components contribute to the protective nature of this product. Given that sugar accounts for over 80% of honey and up to 25% of this sugar is composed of oligosaccharides, we have investigated the anti-infective activity of manuka honey oligosaccharides against a range of pathogens. Initially, oligosaccharides were extracted from a commercially-available New Zealand manuka honey—MGO™ Manuka Honey (Manuka Health New Zealand Ltd.)—and characterized by High pH anion exchange chromatography coupled with pulsed amperiometric detection. The adhesion of specific pathogens to the human colonic adenocarcinoma cell line, HT-29, was then assessed in the presence and absence of these oligosaccharides. Manuka honey oligosaccharides significantly reduced the adhesion of Escherichia coli O157:H7 (by 40%), Staphylococcus aureus (by 30%), and Pseudomonas aeruginosa (by 52%) to HT-29 cells. This activity was then proven to be concentration dependent and independent of bacterial killing. This study identifies MGO™ Manuka Honey as a source of anti-infective oligosaccharides for applications in functional foods aimed at lowering the incidence of infectious diseases

Exposure of Bifidobacterium longum subsp. infantis to Milk Oligosaccharides Increases Adhesion to Epithelial Cells and Induces a Substantial Transcriptional Response

Devon Kavanaugh is in receipt of a Teagasc Walsh Fellowship. The authors would also like to acknowledge the support of Science Foundation Ireland under Grant No. 08/SRC/B1393 and the Alimentary Glycoscience Research Cluster (AGRC).peer-reviewedIn this study, we tested the hypothesis that milk oligosaccharides may contribute not only to selective growth of bifidobacteria, but also to their specific adhesive ability. Human milk oligosaccharides (3′sialyllactose and 6′sialyllactose) and a commercial prebiotic (Beneo Orafti P95; oligofructose) were assayed for their ability to promote adhesion of Bifidobacterium longum subsp. infantis ATCC 15697 to HT-29 and Caco-2 human intestinal cells. Treatment with the commercial prebiotic or 3′sialyllactose did not enhance adhesion. However, treatment with 6′sialyllactose resulted in increased adhesion (4.7 fold), while treatment with a mixture of 3′- and 6′-sialyllactose substantially increased adhesion (9.8 fold) to HT-29 intestinal cells. Microarray analyses were subsequently employed to investigate the transcriptional response of B. longum subsp. infantis to the different oligosaccharide treatments. This data correlated strongly with the observed changes in adhesion to HT-29 cells. The combination of 3′- and 6′-sialyllactose resulted in the greatest response at the genetic level (both in diversity and magnitude) followed by 6′sialyllactose, and 3′sialyllactose alone. The microarray data was further validated by means of real-time PCR. The current findings suggest that the increased adherence phenotype of Bifidobacterium longum subsp. infantis resulting from exposure to milk oligosaccharides is multi-faceted, involving transcription factors, chaperone proteins, adhesion-related proteins, and a glycoside hydrolase. This study gives additional insight into the role of milk oligosaccharides within the human intestine and the molecular mechanisms underpinning host-microbe interactions.Science Foundation IrelandTeagasc Walsh Fellowship Programm

Bifidobacterium longum subsp. infantis ATCC 15697 and Goat Milk Oligosaccharides Show Synergism In Vitro as Anti-Infectives against Campylobacter jejuni

peer-reviewedBifidobacteria are known to inhibit, compete with and displace the adhesion of pathogens to human intestinal cells. Previously, we demonstrated that goat milk oligosaccharides (GMO) increased the attachment of Bifidobacterium longum subsp. infantis ATCC 15697 to intestinal cells in vitro. In this study, we aimed to exploit this effect as a mechanism for inhibiting pathogen association with intestinal cells. We examined the synergistic effect of GMO-treated B. infantis on preventing the attachment of a highly invasive strain of Campylobacter jejuni to intestinal HT-29 cells. The combination decreased the adherence of C. jejuni to the HT-29 cells by an average of 42% compared to the control (non-GMO treated B. infantis). Increasing the incubation time of the GMO with the Bifidobacterium strain resulted in the strain metabolizing the GMO, correlating with a subsequent 104% increase in growth over a 24 h period when compared to the control. Metabolite analysis in the 24 h period also revealed increased production of acetate, lactate, formate and ethanol by GMO-treated B. infantis. Statistically significant changes in the GMO profile were also demonstrated over the 24 h period, indicating that the strain was digesting certain structures within the pool such as lactose, lacto-N-neotetraose, lacto-N-neohexaose 3′-sialyllactose, 6′-sialyllactose, sialyllacto-N-neotetraose c and disialyllactose. It may be that early exposure to GMO modulates the adhesion of B. infantis while carbohydrate utilisation becomes more important after the bacteria have transiently colonised the host cells in adequate numbers. This study builds a strong case for the use of synbiotics that incorporate oligosaccharides sourced from goat′s milk and probiotic bifidobacteria in functional foods, particularly considering the growing popularity of formulas based on goat milk

Mining Milk for Factors which Increase the Adherence of Bifidobacterium longum subsp. infantis to Intestinal Cells

peer-reviewedBifidobacteria play a vital role in human nutrition and health by shaping and maintaining the gut ecosystem. In order to exert a beneficial effect, a sufficient population of bifidobacteria must colonise the host. In this study, we developed a miniaturised high-throughput in vitro assay for assessing the colonising ability of bacterial strains in human cells. We also investigated a variety of components isolated from different milk sources for their ability to increase the adherence of Bifidobacterium longum subsp. infantis ATCC 15697, a common member of the gastrointestinal microbiota of breastfed infants, to HT-29 cells. Both conventional and miniaturised colonisation assays were employed to examine the effect of 13 different milk-derived powders on bacterial adherence, including positive controls which had previously resulted in increased bifidobacterial adherence (human milk oligosaccharides and a combination of 3′- and 6′-sialylactose) to intestinal cells. Immunoglobulin G enriched from bovine whey and goat milk oligosaccharides resulted in increased adhesion (3.3- and 8.3-fold, respectively) of B. infantis to the intestinal cells and the miniaturised and conventional assays were found to yield comparable and reproducible results. This study highlights the potential of certain milk components to favourably modulate adhesion of bifidobacteria to human intestinal cells

Is Endoscopic Band Ligation a Superior Treatment Modality for Gastric Antral Vascular Ectasia Compared to Argon Plasma Coagulation?

Background/Aims Gastric antral vascular ectasia (GAVE) is a rare acquired vascular lesion of the gastric antrum. The most frequent presentation of GAVE is iron deficiency anemia. Endoscopic therapy is the mainstay of treatment. However, there is no consensus regarding the optimal treatment modality. Methods A retrospective cohort study was performed on patients with GAVE, including patients receiving endoscopic therapy. Treatment was with either argon plasma coagulation (APC) or endoscopic band ligation (EBL). Basic demographic data, indication for index procedure, number of sessions, and pre- and post-hemoglobin levels were collected. The aim of the study was to compare outcomes across the two treatment modalities. Results One hundred and seventeen diagnoses of GAVE were made. Sixty-two patients (53%) required endoscopic treatment for symptomatic GAVE (female, n=38, 61%; mean age of 74.4 years). Two hundred and eighteen procedures were performed during the study period. APC was performed (n=161, 74%) more frequently than EBL (n=57, 26%). Patients treated with APC at index required a median 5 subsequent therapeutic interventions (APC or EBL), while those treated with EBL at index required a further 2.9 treatments (EBL only) (p<0.05). Conclusions APC was the most common treatment modality employed. We demonstrate an increasing incidence of EBL. Patients treated with EBL at index treatment required fewer subsequent treatment sessions and had a greater mean rise in hemoglobin. This suggests a more effective endoscopic response with EBL

Changes to the Oligosaccharide Profile of Bovine Milk at the Onset of Lactation

peer-reviewedNumerous bioactive components exist in human milk including free oligosaccharides, which represent some of the most important, and provide numerous health benefits to the neonate. Considering the demonstrated value of these compounds, much interest lies in characterising structurally similar oligosaccharides in the dairy industry. In this study, the impacts of days post-parturition and parity of the cows on the oligosaccharide and lactose profiles of their milk were evaluated. Colostrum and milk samples were obtained from 18 cows 1–5 days after parturition. Three distinct phases were identified using multivariate analysis: colostrum (day 0), transitional milk (days 1–2) and mature milk (days 3–5). LS-tetrasaccharide c, lacto-N-neotetraose, disialyllacto-N-tetraose, 3’-sial-N-acetyllactosamine, 3’-sialyllactose, lacto-N-neohexaose and disialyllactose were found to be highly affiliated with colostrum. Notably, levels of lactose were at their lowest concentration in the colostrum and substantially increased 1-day post-parturition. The cow’s parity was also shown to have a significant effect on the oligosaccharide profile, with first lactation cows containing more disialyllacto-N-tetraose, 6’-sialyllactose and LS-tetrasaccharide compared to cows in their second or third parity. Overall, this study identifies key changes in oligosaccharide and lactose content that clearly distinguish colostrum from transitional and mature milk and may facilitate the collection of specific streams with divergent biological functions

Understanding implementation of maternal acute illness management education by measuring capability, opportunity and motivation : a mixed methods study in a low-income country

A major cause of maternal death in low-income countries is a lack of adequate healthcare. The dominant approach to improving care involves continuing professional development but little is known about their impact on practice. Less still is known about the determinants of practice change and barriers to implementation. This study investigated the implementation of an acute illness management course on Ugandan health professionals’ practice and determinants of practice change. Before and after training, 51 nurses, midwives, doctors and clinical officers completed tests of knowledge. Immediately post-course and 1-month later, participants completed questions assessing intention to change practice, practice and determinants of change. Post course, participants took part in focus groups. Post-course, participants reported that they were capable and were motivated to use their knowledge and skills in practice and a lower belief in opportunity to change practice. Behavioural intention was very high and behaviour 1 month later was statistically significantly lower. Three themes emerged: 1) systematic approach changing clinical practice, 2) inter-professional communication, and 3) barriers and facilitators to implementation. Educators should consider behaviour change determinants as important assessments of outcome because they provide crucial implementation of training into practice

Respiratory and Urinary Tract Infections, Arthritis, and Asthma Associated with HTLV-I and HTLV-II Infection

Human T-lymphotropic virus types I and II (HTLV-I and -II) cause myelopathy; HTLV-I, but not HTLV-II, causes adult T-cell leukemia. Whether HTLV-II is associated with other diseases is unknown. Using survival analysis, we studied medical history data from a prospective cohort of HTLV-I– and HTLV-II–infected and –uninfected blood donors, all HIV seronegative. A total of 152 HTLV-I, 387 HTLV-II, and 799 uninfected donors were enrolled and followed for a median of 4.4, 4.3, and 4.4 years, respectively. HTLV-II participants had significantly increased incidences of acute bronchitis (incidence ratio [IR] = 1.68), bladder or kidney infection (IR = 1.55), arthritis (IR = 2.66), and asthma (IR = 3.28), and a borderline increase in pneumonia (IR = 1.82, 95% confidence interval [CI] 0.98 to 3.38). HTLV-I participants had significantly increased incidences of bladder or kidney infection (IR = 1.82), and arthritis (IR = 2.84). We conclude that HTLV-II infection may inhibit immunologic responses to respiratory infections and that both HTLV-I and -II may induce inflammatory or autoimmune reactions