Optimized NMR-Based Metabolomic Protocol for Salivary Analysis in Clinical Practice.

Coexistence of obesity and asthma determines a distinct respiratory metabolic phenotype

Real-time in-situ measurement of hydrogel swelling by single sided NMR

In controlled drug delivery, the drug diffusion coefficient in a given matrix is a key factor for predicting its release rate. In this work, we compare 31P nuclear magnetic resonance (NMR) profiling for obtaining the mutual-diffusion coefficient () of a drug in hydrogel with results obtained from conventional source/sink experiments. Despite the fact that NMR profiling is a powerful approach for measuring transport properties, it is rarely used for characterizing drug diffusion in gel matrices in pharmaceutical sciences. This work provides an illustration of the applicability of this technique and highlights its advantages for studying drug release systems. The comparison with results obtained from the source/sink experiment clearly establishes the validity of the NMR profiling approach. Alendronate was used as a model drug while curdlan, a gel-forming bacterial polysaccharide, served as a model biomaterial. The determined value (5.6 ± 0.3 × 10−10 m2/s) agrees with the one obtained from a conventional source/sink experiment (5.4 ± 0.5 × 10−10 m2/s). In addition, the alendronate self-diffusion coefficients in solution () and in the hydrogel () were measured on the same system using pulse-field gradient (PFG) 31P NMR. These supplementary parameters provided a more detailed characterization of the drug transport properties in the gel matrix.

Paintings on canvas are complex structures created by superimposing layers of different composition. Investigations on the structure of these artworks can provide essential information on their state of conservation, pictorial technique, possible overpaintings, and in planning a proper conservation plan. Standard methods of investigation consist in sampling a limited number of fragments for stratigraphic analyses. Despite the recognized validity of these methods, they are affected by evident limitations. Nuclear magnetic resonance (NMR) profiling, often named NMR stratigraphy, is an NMR relaxometry technique applied by single-sided portable devices developed to overcome the disadvantages of microinvasive stratigraphic analyses. The potential of this approach on artworks, including wall paintings and a few examples of painted canvas, is described in the literature. In this study, NMR profiles of painting on canvas were examined by analyzing transverse relaxation time data by T2 quasi-continuous distributions and the results compared with standard stratigraphic cross-sections analysis. Combining signal intensity and T2 quasi-continuous distributions, the identification of textile, preparatory, and paint layers was enhanced. The diction "NMR stratigraphy" for these inhomogeneous layered artworks is also discussed. Indeed, unlike the stratigraphic cross-sections, NMR profiles provide information on a volume (flat slice), rather than on a surface, and the collected signal can derive from nonuniform and partially overlapping layers. This study paves the way for extensive investigations on relaxation time quasi-continuous distributions in various binder/pigment mixtures in order to improve the reliability of NMR profile as an innovative, non-invasive, and nondestructive method for analyzing paintings on canvas.

This study presents a new strategy to discriminate between opium samples obtained from different geographical regions. Nuclear magnetic resonance (NMR) profiling and chemometrics were applied to geographical classification of opium originating from Myanmar and Afghanistan, which are two major opium producing countries in the world. A total of 50 Myanmar and 46 Afghanistan authentic opium samples were analyzed by 1H-NMR, and the chemical profiles were characterized. Different sample preparation procedures, data processing methods, and chemometrics were compared to obtain the best classification effect. It was found that drying and the addition of buffer solutions were unnecessary for classification purposes; thus, the gum opium samples were extracted directly with CD3OD, which shortened sample preparation time. A full discrimination between the two geographical origins was achieved by 1H-NMR profiling and orthogonal partial least squares discriminant analysis. All 30 opium samples were classified correctly by the developed orthogonal partial least squares discriminant analysis model. Compared with traditional chromatography and mass spectrometry profiling methods, the 1H-NMR profiling method was faster (with instrument analysis time of less than 3min) and reproducible. This study provides new insights into the applying of NMR profiling and chemometrics to rapid drug profiling analysis.

Neonatal encephalopathy (NE) is a major cause of mortality and severe neurological disability in the neonatal period and beyond. We hypothesized that the degree of brain injury is reflected in the molecular composition of peripheral blood samples. A sub-cohort of 28 newborns included in the HYPOTOP trial was studied. Brain injury was assessed by magnetic resonance imaging (MRI) once per patient and neurodevelopment at 24 months of age was evaluated using the Bayley III Scales of Infant and Toddler Development. The nuclear magnetic resonance (NMR) profile of 60 plasma samples collected before, during, and after cooling was recorded. In total, 249 molecular features were quantitated in plasma samples from newborns and postnatal age showed to affect detected NMR profiles. Lactate, beta-hydroxybutyrate, pyruvate, and three triglyceride biomarkers showed the ability to discern between different degrees of brain injury according to MRI scores. The prediction performance of lactate was superior as compared to other clinical and biochemical parameters. This is the first longitudinal study of an ample compound panel recorded by NMR spectroscopy in plasma from NE infants. The serial determination of lactate confirms its solid position as reliable candidate biomarker for predicting the severity of brain injury. The use of nuclear magnetic resonance (NMR) spectroscopy enables the simultaneous quantitation of 249 compounds in a small volume (i.e., 100 μL) of plasma. Longitudinal perturbations of plasma NMR profiles were linked to magnetic resonance imaging (MRI) outcomes of infants with neonatal encephalopathy (NE). Lactate, beta-hydroxybutyrate, pyruvate, and three triglyceride biomarkers showed the ability to discern between different degrees of brain injury according to MRI scores. Lactate is a minimally invasive candidate biomarker for early staging of MRI brain injury in NE infants that might be readily implemented in clinical guidelines for NE outcome prediction.

Sample preparation for proteomics analysis is one of the most crucial processes that is often time consuming and laborious, which makes parallel handling of high‐throughput samples difficult. In proteomics studies, availability of reproducible and sensitive methods is a prerequisite for qualitative and quantitative analyses of high‐throughput data to identify potential biomarker candidates from biological samples. The greatest strength of any sample preparation protocol is the reproducibility of extraction, solubilization, and digestion of proteins. Therefore, the present study was planned to automate filter‐aided sample preparation (FASP) protocol that is widely used at present in proteomics analysis. We tested the efficiency of an automated sample preparation platform for handling 96 samples in parallel, which reduced the time and cost of analysis. Samples were added to a 96‐well filter plate, and proteins present in the samples were trapped, denatured, reduced, alkylated, and digested with trypsin. The eluted peptides were analyzed using mass spectrometry MS/MS. Buffer exchanges, which were previously performed using centrifugation, were performed by controlling the vacuum pressure. Different concentrations of bovine serum albumin (BSA) were used for optimizing the pressure and time required for the efficient elution and identification of peptides. The optimized conditions were evaluated using tissue samples with manual and automated FASP protocols and the eluted peptides were analyzed using liquid chromatography LC‐MS/MS. Results showed that the automated FASP (a‐FASP) protocol could efficiently handle large sample sets in a reproducible and quantifiable manner. Thus, inclusion of this automated protocol in proteomics analysis could help in handling high‐throughput data in less time and with minimal error.

Robust assessment of sample preparation protocols for proteomics of cells and tissues

A solid-phase extraction procedure coupled to 1H NMR, with chemometric analysis, to seek reliable markers of the botanical origin of honey

<p>Hydrous lattice point defects (OH defects) in quartz (SiO<sub>2</sub>) occur through coupled substitution of Si<sup>4+</sup> with a trivalent cation (most commonly Al<sup>3+</sup>) and a hydroxyl group (OH<sup>-</sup>). These impurities can be used to investigate its host rock’s crystallization history and may therefore also serve as a tracer for sediment provenance analyses, but are also economically relevant (e.g., high purity quartz sources).</p><p>Transmission infrared (IR) spectroscopy has proven to be a very effective method to analyze OH defects down to concentrations of a few weight parts per million water equivalent. This technique, however, requires thin (100 to 200 µm), polished quartz wafers that are cut perpendicular to the crystallographic c-axis. Preparation of a statistically significant number (i.e. > 100) of grains using this approach is very time consuming and requires a skilled operator. Furthermore, IR spectral analysis so far does not follow a standardized protocol, possibly introducing individual biases and hampering reproducibility of as well as comparability between datasets.</p><p>In this work, we present a new, standardized procedure for sample preparation, measurement, and data analysis of OH defects in quartz. Sample preparation and IR measurements are significantly sped up and simplified and require relatively little specialized laboratory equipment. Additionally, our data analysis is performed largely automated and based on spectral deconvolution and generation of synthetic spectra before quantification, ensuring quick generation of reproducible results. This new protocol may therefore be another step towards making OH defect analysis accessible to a wider range of geoscientific fields.</p>

In previous studies, 11 elements (Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se, and Zn) were determined in 30-minute aerosol samples collected with the University of Maryland Semicontinuous Elements in Aerosol Sampler (SEAS; Kidwell and Ondov, 2001, 2004; SEAS-II) in several locations in which air quality is influenced by emissions from coal- or oil-fired power plants. At this time resolution, plumes from stationary high temperature combustion sources are readily detected as large excursions in ambient concentrations of elements emitted by these sources (Pancras et al. ). Moreover, the time-series data contain intrinsic information on the lateral diffusion of the plume (e.g., {sigma}{sub y}), which Park et al. (2005 and 2006) have exploited in their Pseudo-Deterministic Receptor Model (PDRM), to calculate emission rates of SO{sub 2} and 11 elements (mentioned above) from four individual coal- and oil-fired power plants in the Tampa Bay area. In the current project, we proposed that the resolving power of source apportionment methods might be improved by expanding the set of maker species and that there exist some optimum set of marker species that could be used. The ultimate goal was to determine the utility of using additional elements to better identify and isolate contributions of individual power plants to ambient levels of PM and its constituents. And, having achieved better resolution, achieve, also, better emission rate estimates. In this study, we optimized sample preparation and instrumental protocols for simultaneous analysis of 28 elements in dilute slurry samples collected with the SEAS with a new state-of-the-art Thermo-Systems, Inc., X-series II, Inductively Coupled Plasma Mass Spectroscopy (ICP-MS), and reanalyzed the samples previously collected in Tampa during the modeling period studied by Park et al. (2005) in which emission rates from four coal- and oil-fired power plants affected air quality at the sampling site. In the original model, Park et al. (2005), included 6 sources. Herein, we reassessed the number of contributing sources in light of the new data. A comprehensive list of sources was prepared and both our Gaussian Plume model and PMF were used to identify and predict the relative strengths of source contributions at the receptor sites. Additionally, PDRM was modified to apply National Inventory Emissions, Toxic Release Inventory, and Chemical Mass Balance source profile data to further constrain solutions. Both the original Tampa data set (SO{sub 2} plus 11 elements) and the new expanded data set (SO{sub 2} plus 23 elements) were used to resolve the contributions of particle constituents and PM to sources using Positive Matrix Factorization (PMF) and PDRM.

Whole genome sequencing (WGS) via next-generation sequencing (NGS) platforms offers a powerful approach for investigating viral genetic diversity. Orbiviruses are an economically important group of arboviruses with a double-stranded RNA (dsRNA) genome consisting of 10 segments. Traditional approaches to virus sequencing relied primarily on processing with various treatments such as lithium chloride to enrich dsRNAs and then sequencing on Illumina platforms due to its lower error rate. To reduce the time and cost associated with orbivirus sequencing, we simplified the sample preparation, sequencing, and analysis protocols. Our optimized sample and library preparation protocols achieved comparable results to established methods while benefiting from simpler sample preparation. The optimized protocols for Illumina and Nanopore platforms (which produces longer reads) resulted in both platforms producing high quality whole genome sequences. To streamline the data analysis, we developed OrbiSeq, a reproducible Nextflow workflow for analysis and consensus sequence generation of orbivirus genomes from Illumina and Nanopore sequence data. While the OrbiSeq pipeline was optimized with orbivirus sequences, it can be used to recover consensus sequences for any segmented or non-segmented viral genome, provided that the sequence is sufficiently similar to existing reference sequences. The optimized protocols for producing viral sequences enhance opportunities for extensive genomic surveillance and in turn deeper evolutionary insights.

Evaluation of postnatal renal function in fetuses with bilateral obstructive uropathies by proton nuclear magnetic resonance spectroscopy

Optimization of analytical and pre-analytical conditions for MALDI-TOF-MS human urine protein profiles

Background:Grewia gum has received attention as a polymeric pharmaceutical excipient in the recent times, being employed as a suspending, film coating, mucoadhesive, and binding agent. The low aqueous solubility, however, has limited its characterization and application.Objective:The purpose of this study was to fractionate and evaluate some physicochemical properties of the gum.Materials and Methods:Aqueous dispersion of the gum was treated at 80°C for 30 min in the presence of sodium chloride and was subsequently fractionated by successively centrifuging it at 3445 rpm for 30 min. Skeletal density, solubility, particle size, and rheological as well as thermal characteristics of the fractions were evaluated. The 1H nuclear magnetic resonance (NMR) and near infrared (NIR) profiles of the fractions were also investigated. The solubility of the gum increased up to fourfold while the viscosity decreased from 244 to as low as70 cP at 40 rpm with some fractions.Results:Grewia gum and the fractions showed good thermal stability exhibiting no thermal events, but charred irreversibly at 297°C irrespective of the fraction. The molecular weight averages by weight and by number of the fractions were between 233,100 and 235,000. The 1H nuclear magnetic resonance (NMR) spectra showed broad peaks. The NMR and NIR spectra suggested the presence of –OH and –OCH3 functional groups in this gum.Conclusion:The fractionation improved solubility and facilitated further investigations on its characteristics that may have implication on its processing, application, and optimization as a potential pharmaceutical excipient.