Analyzing Various Biological Fluids with a Single Automated Proteomic Workflow for Biomarker Discovery.

Protein biomarker discovery in human biological fluids has greatly developed over the past two decades thanks to technological advances allowing deeper proteome coverage and higher sample throughput, among others. While blood samples are most commonly investigated due to their moderate ease of collection and high information content, other biological fluids such as cerebrospinal fluid (CSF) and urine are highly relevant for specific pathologies, such as brain and urologic diseases, respectively. Independently of the biofluid of interest, platforms that can robustly handle a large number of samples are essential in the discovery phase of a clinical study.

Detection of gluten peptides in human duodenal fluids with immuno-liquid chromatography-mass spectrometry.

Gluten proteins are storage proteins in wheat that exhibit a certain resistance to gastrointestinal digestion. To explore solutions to cope with accidental ingestion of gluten in individuals suffering from gluten-related disorders, it is essential to monitor the fate of gluten peptides in biological samples, , gastrointestinal juices, blood plasma or urine. In this work, we aimed at developing a mass spectrometry (MS)-based method for measuring gluten peptides in human duodenal fluids.

Reduction of multiple reaction monitoring protein target list using correlation analysisa.

High mass resolution mass spectrometry provides hundreds to thousands of protein identifications per sample, and quantification is typically performed using label-free quantification. However, the gold standard of quantitative proteomics is multiple reaction monitoring (MRM) using triple quadrupole mass spectrometers and stable isotope reference peptides. This raises the question how to reduce a large data set to a small one without losing essential information.

Proteomics of human biological fluids for biomarker discoveries: technical advances and recent applications.

Introduction: Biological fluids are routine samples for diagnostic testing and monitoring. Blood samples are typically measured because of their moderate invasive collection and high information content on health and disease. Several body fluids, such as cerebrospinal fluid (CSF), are also studied and suited to specific pathologies.

Peptide Characterization and Functional Stability of a Partially Hydrolyzed Whey-Based Formula over Time.

Human clinical trials have shown that a specific partially hydrolyzed 100% whey-based infant formula (pHF-W) reduces AD risk in the first yeast of life. Meta-analyses with a specific pHF-W (pHF-W1) confirm a protective effect while other meta-analyses pooling different pHF-W show conflicting results. Here we investigated the molecular composition and functional properties of the specific pHF-W1 as well as the stability of its manufacturing process over time.

Proteomics of Human Milk: Definition of a Discovery Workflow for Clinical Research Studies.

Milk is a complex biological fluid composed mainly of water, carbohydrates, lipids, proteins, and diverse bioactive factors. Human milk represents a unique tailored source of nutrients that adapts during lactation to the specific needs of the developing infant. Proteins in milk have been studied for decades, and proteomics, peptidomics, and glycoproteomics are the main approaches previously deployed to decipher the proteome of human milk.

Protein levels and protease activity in milk from mothers of pre-term infants: A prospective longitudinal study of human milk macronutrient composition.

Background And Aims: The composition and enzymology of human milk changes throughout the lactation period, and differ for mothers who give birth prematurely compared to those who deliver at full-term. Understanding the composition of milk from mothers of very low birth weight premature infants is of great significance, and the objective of this study was to evaluate the composition, protein profile and plasmin activity of milk from mothers who delivered infants at different gestational ages.

Methods: Samples of human milk were donated by women (n = 74) in the Cork, Ireland, area who gave birth to full-term (>37 weeks gestation, FT), pre-term (32-37 weeks, PT) and very pre-term (≤32 weeks, VPT) infants.

Vitamins and carotenoids in human milk delivering preterm and term infants: Implications for preterm nutrient requirements and human milk fortification strategies.

Differences in vitamin and carotenoids content of human milk (HM) produced for infants born at term and preterm is poorly understood. In this study, HM was collected weekly for four and two months post-partum for preterm and term groups, respectively. Nutrients of interest, from single full breast expressions were measured by liquid chromatography coupled with mass spectrometry.

Exploration of human cerebrospinal fluid: A large proteome dataset revealed by trapped ion mobility time-of-flight mass spectrometry.

Cerebrospinal fluid (CSF) is a biofluid in direct contact with the brain and as such constitutes a sample of choice in neurological disorder research, including neurodegenerative diseases such as Alzheimer or Parkinson. Human CSF has still been less studied using proteomic technologies compared to other biological fluids such as blood plasma or serum. In this work, a pool of "normal" human CSF samples was analysed using a shotgun proteomic workflow that combined removal of highly abundant proteins by immunoaffinity depletion and isoelectric focussing fractionation of tryptic peptides to alleviate the complexity of the biofluid.

Nightside condensation of iron in an ultrahot giant exoplanet.

Ultrahot giant exoplanets receive thousands of times Earth's insolation. Their high-temperature atmospheres (greater than 2,000 kelvin) are ideal laboratories for studying extreme planetary climates and chemistry. Daysides are predicted to be cloud-free, dominated by atomic species and much hotter than nightsides.

Progress and pitfalls of using isobaric mass tags for proteome profiling.

: Quantitative proteomics using mass spectrometry is performed label-free or label-based approaches. Labeling strategies rely on the incorporation of stable heavy isotopes by metabolic, enzymatic, or chemical routes. Isobaric labeling uses chemical labels of identical masses but of different fragmentation behaviors to allow the relative quantitative comparison of peptide/protein abundances between biological samples.

Subclinical Mastitis in a European Multicenter Cohort: Prevalence, Impact on Human Milk (HM) Composition, and Association with Infant HM Intake and Growth.

Subclinical mastitis (SCM) is an inflammatory condition of the mammary gland. We examined the effects of SCM on human milk (HM) composition, infant growth, and HM intake in a mother-infant cohort from seven European countries. HM samples were obtained from 305 mothers at 2, 17, 30, 60, 90, and 120 days postpartum.

Longitudinal Changes of Mineral Concentrations in Preterm and Term Human Milk from Lactating Swiss Women.

An adequate mineral supply to preterm infants is essential for normal growth and development. This study aimed to compare the mineral contents of human milk (HM) from healthy mothers of preterm (28-32 weeks) and full term (>37 weeks) infants. Samples were collected weekly for eight weeks for the term group ( = 34) and, biweekly up to 16 weeks for the preterm group ( = 27).

Longitudinal Analysis of Macronutrient Composition in Preterm and Term Human Milk: A Prospective Cohort Study.

Background: Mother's own milk is the optimal source of nutrients and provides numerous health advantages for mothers and infants. As they have supplementary nutritional needs, very preterm infants may require fortification of human milk (HM). Addressing HM composition and variations is essential to optimize HM fortification strategies for these vulnerable infants.

Temporal Progression of Fatty Acids in Preterm and Term Human Milk of Mothers from Switzerland.

We longitudinally compared fatty acids (FA) from human milk (HM) of mothers delivering term and preterm infants. HM was collected for 4 months postpartum at 12 time points for preterm and for 2 months postpartum at 8 time points for term group. Samples were collected from the first feed of the morning, and single breast was fully expressed.

Analytical Method for Lactoferrin in Milk-Based Infant Formulas by Signature Peptide Quantification with Ultra-High Performance LC-Tandem Mass Spectrometry.

There is a need for a standardized method for quantification of lactoferrin in infant formulas, and manufacturers have started fortifying lactoferrin to mimic the higher levels found in human milk. A variety of current methods exist, but specificity and accuracy are challenging with the infant formula matrix. The use of signature peptides and MS is becoming more prevalent in the realm of analytical chemistry for quantification of proteins.

Comparison of macronutrient content in human milk measured by mid-infrared human milk analyzer and reference methods.

Objective: The study aims at evaluating mid-infrared human milk analyzer (HMA) accuracy and precision, in human milk (HM).

Study Design: Röse-Gottlieb, high-performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD), Kjeldahl and amino acid analysis (AA) were selected as references for total fat, lactose and total protein determination.

Results: No significant difference was observed in lactose content between HMA and HPAEC-PAD.

Temporal changes of major protein concentrations in preterm and term human milk. A prospective cohort study.

Background: Proteins are major contributors to the beneficial effects of human milk (HM) on preterm infant health and development. Alpha-lactalbumin, lactoferrin, serum albumin and caseins represent approximately 85% of the total HM protein. The temporal changes of these proteins in preterm (PT) HM and its comparison with term (T) HM is poorly characterized.

Amino Acid Composition of Breast Milk from Urban Chinese Mothers.

Human breast milk (BM) amino acid (AA) composition may be impacted by lactation stage or factors related to geographical location. The present cross-sectional study is aimed at assessing the temporal changes of BMAA over lactation stages in a large cohort of urban mothers in China. Four hundred fifty BM samples, collected in three Chinese cities covering eight months of lactation were analyzed for free (FAA) and total (TAA) AA by o-phthalaldehyde/ fluorenylmethylchloroformate (OPA/FMOC) derivatization.

Temporal Changes of Protein Composition in Breast Milk of Chinese Urban Mothers and Impact of Caesarean Section Delivery.

Human breast milk (BM) protein composition may be impacted by lactation stage or factors related to geographical location. The present study aimed at assessing the temporal changes of BM major proteins over lactation stages and the impact of mode of delivery on immune factors, in a large cohort of urban mothers in China. 450 BM samples, collected in three Chinese cities, covering 8 months of lactation were analyzed for α-lactalbumin, lactoferrin, serum albumin, total caseins, immunoglobulins (IgA, IgM and IgG) and transforming growth factor (TGF) β1 and β2 content by microfluidic chip- or ELISA-based quantitative methods.

In vitro activity of commercial probiotic Lactobacillus strains against uropathogenic Escherichia coli.

Urinary tract infection (UTI) is one of the most prevalent infections in humans. In ≥80% of cases, the etiologic agents are strains of uropathogenic Escherichia coli (UPEC), which commonly reside in the gastrointestinal tract. Lactobacilli have been shown to prevent UTI reoccurrence by restoring the urogenital microbiota when administered vaginally or orally.

Food peptidomics: large scale analysis of small bioactive peptides--a pilot study.

Unlabelled: Food peptidomics deals in part with the identification and quantification of nutritionally relevant peptides which are called bioactive peptides. This category of peptides comprises large, medium to small peptides. However, small peptides (2-6 amino acids) represent by far the largest category.

High accuracy alignment facility for the receiver and transmitter of the BepiColombo Laser Altimeter.

The accurate co-alignment of the transmitter to the receiver of the BepiColombo Laser Altimeter is a challenging task for which an original alignment concept had to be developed. We present here the design, construction and testing of a large collimator facility built to fulfill the tight alignment requirements. We describe in detail the solution found to attenuate the high energy of the instrument laser transmitter by an original beam splitting pentaprism group.

A nutrigenomics view of protein intake: macronutrient, bioactive peptides, and protein turnover.

Proteins are needed for the development and sustainability of life. They are the molecular machines and building blocks in the human body that drive or exert most biological functions and confer structure and function to cell and tissue architecture. Dietary proteins provide essential amino acids and complement lipid and carbohydrate as a major source of energy.