Glycosylation of Human Milk Lactoferrin Exhibits Dynamic Changes During Early Lactation Enhancing Its Role in Pathogenic Bacteria-Host Interactions

In specific plant organs, namely the root nodules of alfalfa, fixed nitrogen (ammonia) produced by the symbiotic partner Sinorhizobium meliloti supports the growth of the host plant in nitrogen-depleted environment. Here, we report that a derivative of S. meliloti carrying a mutation in the chromosomal ntrR gene induced nodules with enhanced nitrogen fixation capacity, resulting in an increased dry weight and nitrogen content of alfalfa. The efficient nitrogen fixation is a result of the higher expression level of the nifH gene, encoding one of the subunits of the nitrogenase enzyme, and nifA, the transcriptional regulator of the nif operon. The ntrR gene, controlled negatively by its own product and positively by the symbiotic regulator syrM, is expressed in the same zone of nodules as the nif genes. As a result of the nitrogen-tolerant phenotype of the strain, the beneficial effect of the mutation on efficiency is not abolished in the presence of the exogenous nitrogen source. The ntrR mutant is highly competitive in nodule occupancy compared with the wild-type strain. Sequence analysis of the mutant region revealed a new cluster of genes, termed the “ntrPR operon,” which is highly homologous to a group of vap-related genes of various pathogenic bacteria that are presumably implicated in bacterium-host interactions. On the basis of its favorable properties, the strain is a good candidate for future agricultural utilization.

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Lutein concentration in human milk during early lactation and its relationship with dietary lutein intake

Public Health Nutrition ◽

10.1017/s1368980009004807 ◽

2009 ◽

Vol 12 (10) ◽

pp. 1878-1884 ◽

Cited By ~ 15

Author(s):

Hellas Cena ◽

Anna Maria Castellazzi ◽

Amedeo Pietri ◽

Carla Roggi ◽

Giovanna Turconi

Keyword(s):

Breast Milk ◽

Human Milk ◽

Maternal Plasma ◽

Cross Sectional Study ◽

Early Lactation ◽

Dietary Recommendations ◽

Mature Milk ◽

Cross Sectional ◽

Pregnancy And Lactation ◽

Age Range

AbstractObjectiveThe present study aimed to estimate the lutein concentration in human milk during early lactation and its relationship with dietary lutein intake measured through the administration of a short FFQ.DesignA cross-sectional study in which an FFQ was administered twice: on day 3 (T0) and day 30 (T1) postpartum; meanwhile two breast milk samples were collected. Maternal plasma samples were obtained at T0. The comparison of dietary lutein intakes and likewise lutein concentrations in breast milk at T0 and T1 were analysed with Student’sttest. Pearson’s correlation coefficient was used to determine the association between dietary lutein intake and lutein concentration in milk and plasma, respectively, as well as the correlation between breast milk and plasma lutein concentrations at T0.SettingPavia, northern Italy.SubjectsTwenty-one pregnant women, age range 24–42 years, were recruited during their last trimester on a voluntary basis.ResultsBoth breast milk and plasma lutein concentrations were significantly correlated with dietary lutein intake (r= 0·86,P= 0·0001 andr= 0·94,P= 0·0001, respectively). There was a clear significant correlation between milk and plasma lutein concentrations (r= 0·87,P= 0·0001). Mature milk lutein concentration, although significantly reduced at T1 (P< 0·01), maintained a fairly high correlation with dietary lutein intake (r= 0·82,P= 0·0001).ConclusionsEven though milk lutein concentration decreased during early lactation, it remained significantly correlated with daily lutein intake. Therefore, while awaiting further research, dietary recommendations advising intake of fresh fruit and vegetables rich in lutein, throughout the whole duration of pregnancy and lactation, are extremely useful.

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Microbial-Host Interactions at Mucosal Sites. Host Response to Pathogenic Bacteria at Mucosal Sites

Defense of Mucosal Surfaces: Pathogenesis, Immunity and Vaccines - Current Topics in Microbiology and Immunology ◽

10.1007/978-3-642-59951-4_9 ◽

1999 ◽

pp. 163-189 ◽

Cited By ~ 6

Author(s):

A. Phalipon ◽

P. J. Sansonetti

Keyword(s):

Host Response ◽

Pathogenic Bacteria ◽

Host Interactions ◽

Microbial Host

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Roles of flagella in pathogenic bacteria and bacterial–host interactions

Bacterial–Epithelial Cell Cross-Talk ◽

10.1017/cbo9780511541537.005 ◽

2009 ◽

pp. 131-157

Author(s):

Glenn M. Young

Keyword(s):

Pathogenic Bacteria ◽

Bacterial Host ◽

Host Interactions

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Some Properties of Cells Cultured From Early-Lactation Human Milk

JNCI Journal of the National Cancer Institute ◽

10.1093/jnci/58.6.1563 ◽

1977 ◽

Vol 58 (6) ◽

pp. 1563-1571 ◽

Cited By ~ 59

Author(s):

J. Taylor-Papadimitriou ◽

M. Shearer ◽

R. Tilly

Keyword(s):

Human Milk ◽

Early Lactation ◽

Cells Cultured

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Feasibility of Standardized Human Milk Collection in Neonatal Care Units

Scientific Reports ◽

10.1038/s41598-019-50560-y ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Laura Galante ◽

Mark H. Vickers ◽

Amber M. Milan ◽

Clare M. Reynolds ◽

Tanith Alexander ◽

...

Keyword(s):

Human Milk ◽

Preterm Infants ◽

Standard Protocol ◽

Early Lactation ◽

Milk Supply ◽

Sampling Protocol ◽

Late Preterm Infants ◽

Time Points ◽

Human Lactation ◽

Standardized Protocol

Abstract Research in human lactation is a growing field. However, difficulties in studying human milk originate from the dynamicity of its composition. Using standardized collection protocols is mandatory to minimize variation and warrant comparability of findings across different studies. Yet, information on the feasibility of collecting human milk with standardized procedures, especially in neonatal units, are lacking. The present study aims to report on the feasibility and difficulties to collect human milk according to a standardized protocol, during early lactation from women who gave birth to preterm infants. Human milk was collected from 129 mothers of moderate- to late-preterm infants according to two variations of a standard protocol which differed for number of collection time-points. Collection rates and adherence to the sampling protocol were evaluated together with reason for missed collection. Collection of ≥1 sample was successful for 80% of the mothers. However adherence to the standard protocol was overall low (36% and 27%). Collection rates were different between the two protocol variations (73% against 92%, p ≤ 0.001). Amongst the reason for missed collection, low milk supply was the most recurrent (40%). Our findings show that while collecting human milk in neonatal units is achievable, obtaining standard and comparable samples results challenging.

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Adapting a Phage to Combat Phage Resistance

Antibiotics ◽

10.3390/antibiotics9060291 ◽

2020 ◽

Vol 9 (6) ◽

pp. 291

Author(s):

Elina Laanto ◽

Kati Mäkelä ◽

Ville Hoikkala ◽

Janne J. Ravantti ◽

Lotta-Riina Sundberg

Keyword(s):

Pathogenic Bacteria ◽

Bacterial Resistance ◽

Resistance Mechanism ◽

Open Reading Frames ◽

Phage Resistance ◽

Flavobacterium Columnare ◽

Host Interactions ◽

Trade Offs ◽

Short Palindromic Repeat ◽

Experimental Adaptation

Phage therapy is becoming a widely recognized alternative for fighting pathogenic bacteria due to increasing antibiotic resistance problems. However, one of the common concerns related to the use of phages is the evolution of bacterial resistance against the phages, putatively disabling the treatment. Experimental adaptation of the phage (phage training) to infect a resistant host has been used to combat this problem. Yet, there is very little information on the trade-offs of phage infectivity and host range. Here we co-cultured a myophage FCV-1 with its host, the fish pathogen Flavobacterium columnare, in lake water and monitored the interaction for a one-month period. Phage resistance was detected within one day of co-culture in the majority of the bacterial isolates (16 out of the 18 co-evolved clones). The primary phage resistance mechanism suggests defense via surface modifications, as the phage numbers rose in the first two days of the experiment and remained stable thereafter. However, one bacterial isolate had acquired a spacer in its CRISPR (Clustered Regularly Interspaced Short Palindromic Repeat)-Cas locus, indicating that also CRISPR-Cas defense was employed in the phage-host interactions. After a week of co-culture, a phage isolate was obtained that was able to infect 18 out of the 32 otherwise resistant clones isolated during the experiment. Phage genome sequencing revealed several mutations in two open reading frames (ORFs) likely to be involved in the regained infectivity of the evolved phage. Their location in the genome suggests that they encode tail genes. Characterization of this evolved phage, however, showed a direct cost for the ability to infect several otherwise resistant clones—adsorption was significantly lower than in the ancestral phage. This work describes a method for adapting the phage to overcome phage resistance in a fish pathogenic system.

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