Evaluation of the proteomic profile in patients with celiac disease and malabsorption syndrome

The malabsorption syndrome includes many clinical units that lead to chronic diarrhea and malnutrition. In celiac disease and small intestine bacterial overgrowth making the diagnosis is not always straightforward, and the diagnosis often requires combining blood antibody tests, intestinal biopsies, and specific genetic testing. The study aimed to assess patients' protein/peptide profiles with celiac disease (n=31), small intestinal bacterial overgrowth (n=28), and the control group (n=30). Attempts have also been made to identify potential new diagnostic markers. After appropriate preparation, a proteomic analysis of peptides was performed using the MALDI–TOF mass spectrometer. Identified proteins were fibrinogen alpha-chain, kininogen-1, mucin 3A, complement C3, complement C4A, and inter-alpha-trypsin inhibitor heavy chain H4. Performed analyses indicated some proteins that could be potentially involved in the presence of the disease in question and proved that proteomic profiling might serve as a powerful diagnostic tool. Due to the difficulties in celiac disease and small intestine bacterial overgrowth diagnosis, there is a clear need for further investigation of the biological role of proteins potentially involved in the course of the disease.

Mass spectrometry analysis of redox forms of High-Mobility Group Box-1 Protein in cerebrospinal fluid: initial experience

Introduction. High-mobility group box 1 (HMGB1) is an alarmin with proinflammatory potential determined by redox status of the cysteines at position 23 and 45. It may also play a role as a biomarker in biological fluids. The aim of this study was the identification of different HMGB1 redox forms in cerebrospinal fluid (CSF) obtained from subarachnoid hemorrhage patients. Material and Methods. 6 CSF samples were collected from aneurysmal subarachnoid haemorrhage patients. Commercially available HMGB1 isoforms served as a positive control. Immunoprecipitation and electrophoretic isolation of HMGB1 protein were performed, then both CSF and control were analyzed using mass spectrometry technique. To distinguish between fully reduced (thiol group at C23 and C45) and disulfide (disulfide bond connecting C23 and C45) HMGB1 forms, top-down sequencing of the spectra was performed. Results. Top-down sequencing analysis allowed to distinguish between HMGB1 isoforms only in commercially available standard without preceding immunoprecipitation and electrophoresis. MALDI spectra differ i.e. on the fully reduced HMGB1 spectrum fragmentation occurs before and beyond C22, which is not present on the disulfide HMGB1 spectrum. Analysis of HMGB1 isolated from CSF obtained from subarachnoid hemorrhage patients gave no results. Conclusions. Top-down sequencing enables to distinguish between redox forms of HMGB1. Electrophoresis and tryptic digestion cannot precede mass spectrometry analysis of redox forms of HMGB1 due to the reduction of disulfide bonds during these processes. Preferred method of isolation of HMGB1 for direct analysis using top-down sequencing mustn’t include protein digestion or degradation.

The influence of a 3-week body mass reduction program on the metabolic parameters and free amino acid profiles in adult Polish people with obesity

BACKGROUND

Previous studies have showed differences in the amino acid (AA) composition in the plasma of people with obesity when compared to lean individuals, but the perturbations of AA concentrations in obesity and the dynamics of AA changes after weight loss is not fully understood.

OBJECTIVES

The objective of the study was to evaluate the effect of a short-term weight reduction program on the metabolic status and plasma AA levels in individuals with obesity.

MATERIAL AND METHODS

A total of 24 adult Polish patients with a BMI between 34 and 49 kg/m2 were enrolled in a 3-week controlled body mass reduction program based on everyday physical activity and a hypocaloric diet (25-30% less than total daily energy requirements). At baseline and after the program, anthropometric measurements, biochemical parameters and free AA profiles were determined.

RESULTS

After the weight loss program, significant changes in body mass and metabolic parameters (e.g., low-density lipoprotein, triglyceride, fasting glucose, and insulin levels) were observed. Positive changes in a homeostatic model assessment of insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI) following the program were also found. The levels of 10 AAs (α-amino-n-butyric acid, alanine, citrulline, glutamine, glycine, hydroxyproline, isoleucine, proline, sarcosine, and threonine) had significantly increased following weight loss. Only aspartic acid was present at a significantly lower concentration after the program.

CONCLUSIONS

Using a 3-week controlled body mass reduction program based on physical activity and a hypocaloric diet, we were able to demonstrate significant changes in biochemical parameters and free AA profiles. To better understand these changes, future studies should involve a long-term program with more patients.

Amino Acids in Cerebrospinal Fluid of Patients with Aneurysmal Subarachnoid Haemorrhage: An Observational Study

Background

The authors are aware of only one article investigating amino acid concentrations in cerebrospinal fluid (CSF) in patients with ruptured intracranial aneurysms, and this was published 31 years ago. Since then, both management of subarachnoid haemorrhage (SAH) and amino acid assay techniques have seen radical alterations, yet the pathophysiology of SAH remains unclear.

Objective

To analyse the pattern of concentrations of amino acids and related compounds in patients with different outcomes following aneurysmal SAH.

Methods

49 CSF samples were collected from 23 patients on days 0–3, 5, and 10 post-SAH. Concentrations of 33 amino acids and related compounds were assayed by liquid chromatography tandem mass spectrometry in patients with good [Glasgow Outcome Scale (GOS) 1–3] and poor (GOS 4–5) outcome.

Results

Of the 33 compounds assayed, only hydroxyproline and 3-aminoisobutyric acid appeared not to increase significantly following SAH. In poor outcome patients, we found significantly higher concentrations of aspartic acid (p = 0.038), glutamic acid (p = 0.038), and seven other compounds on days 0–3 post-SAH; glutamic acid (p = 0.041) on day 5 post-SAH, and 2-aminoadipic acid (p = 0.033) on day 10 post-SAH. The most significant correlation with GOS at 3 months was found for aminoadipic acid on day 10 post-SAH (cc = −0.81).

Conclusion

Aneurysmal rupture leads to a generalised increase of amino acids and related compounds in CSF. The patterns differ between good and poor outcome cases. Increased excitatory amino acids are strongly indicative of poor outcome.

ANN and Bayesian classification models for virtual screening of endocrine-disrupting chemicals

The identification of endocrine-disrupting chemicals (EDCs) is one of the important goals of environmental chemical hazard screening. The adverse health effects of EDCs in humans have been demonstrated to involve the developmental, reproductive, neurological, cardiovascular, metabolic, and immune systems. The present study reports QSAR classification studies on a large database comprising 8,212 compounds collected from the Estrogenic Activity Database and National Center for Biotechnology Information Database. In this study, four classification models (Bayesian Categorization Model with molecular fingerprints or molecular descriptors as an input and Neural Classification Models with and without Bayesian regularization) were used. Evaluation of these binomial classification methods indicated that the Bayesian method (Bayesian QSAR) works as an excellent method for prediction with fingerprints used as input. In the case of the multilayer perceptron with molecular descriptors as inputs, changing the training mode by introducing a Bayesian regularization algorithm significantly improved ANNs' predictive power. Our goal was to test two popular classification methods suitable for processing large data sets. Such datasets were required to ensure the prediction performances and applicability of the models as a virtual screening tool for an extensive database.

Validation of electrochemical determination of zinc in selected pharmaceutical preparations

A procedure of voltammetric (DP) determination of zinc in two selected pharmaceutical preparations was validated. The source of zinc in the first of them (Bio-Cynk) was the organic salt-gluconate, while the second (Zincteral) contained zinc sulfate. In order to transform zinc into solution, the samples of powdered tablets of each preparation underwent the extraction or mineralisation procedure. The concentration of zinc in solution was determined by differential pulse voltammetry (DP). In the validation process, the selectivity, accuracy, precision and linearity of DP determination of zinc in both preparations were examined. Zinc was determined within the concentration range of 1-20 ppm: the mean recoveries approached 98% in the case of Bio-Cynk and 100% for Zincteral; the errors of determination (RDS) were 2.98-11.5% for Bio-Cynk and 3.06-5.32% for Zincteral, respectively.

Determination of amezinium in plasma by RP HPLC and its application to bioequivalence studies

A modified method is described for the determination of 4-amino-6-methoxy-l-phenylpyridazinium methyl sulfate (amezinium metisulfate) in plasma and in the dosage form. The method involves a sample preparation using SPE and liquid-liquid extraction and subsequent determination by high performance liquid chromatography. Retention time for amezinium was 3.2 min and there was no interference from plasma or amezinium metabolites. The method was applied for the drug determination during comparative studies of two different tablet formulation of amezinium.

Solubility and dissolution rate of ibuprofen in ionic and non-ionic micellar systems

Equilibrium solubility, the profile and the rate of ibuprofen dissolution in solutions of sodium dodecyl sulfate, Tween 60 and Brij 35 were studied. It was found that the solubility of ibuprofen was enhanced by the formed micellar system. The size and shape of formed micelles depended on the used particular surfactant. The mechanism of ibuprofen dissolution in micellar system was discussed.

Simultaneous determination of salicylic acid and acetylsalicylic acid in aspirin delayed-release tablet formulations by second-derivative UV spectrophotometry

A rapid, simple assay procedure was developed for simultaneous analysis of aspirin (ASA) and salicylic acid (SA) in aspirin delayed-release tablet formulation by 'zero crossing' second-derivative UV spectrophotometry. The zero-order absorption spectra and second derivative spectra of ASA and SA were recorded in diluting solution acetonitrile-formic acid (99:1). The accuracy of the method was demonstrated by the determination of ASA and SA in five tablets formulations (each 20 tablets of the same batch) by the described method and by high performance liquid chromatographic method, and the results were in good agreement.

Complexes of Fe(III) ions with mefenamic acid

Mononuclear and binuclear complexes of mefenamic acid with Fe(III) ions of formulae Na[Fe(C15H14O2N)4] and Fe2Cl(C15N14O2N)5 were obtained in the solid phase. Characterization of the complexes was performed by elemental analysis and visible, IR, 1H and 13C NMR spectroscopy and possible structures are proposed.

Studies of neutralizing properties of antacid preparations. Part 7. 27Al NMR studies of aluminum species formed during acid dissolution of some antacid preparations

Neutralization of some aluminum containing antacid preparations with hydrochloric acid were studied by 27Al NMR spectroscopy. It has been found that the nature and composition of aluminum species produced during the acid dissolution of preparations depends upon the substance used and on the pH at which the neutralization reaction proceeds. The results are consistent with the presence of both monomeric and polymeric species in solution containing aluminum in octahedral and tetrahedral environments.

Studies of neutralizing properties of antacid preparations. Part 5: Dissolution kinetics of dihydroxyaluminum aminoacetate

The acid dissolution process of dihydroxyaluminum aminoacetate (1) has been studied by pH-stat method. The neutralization reaction was examined by monitoring the appearance of aluminum ion and aminoacetic acid in the reaction medium. The Weibull distribution function was applied to the quantitative interpretation of neutralization rate data. The mechanism of acid neutralization of 1 is discussed.

Studies of neutralizing properties of antacid preparations. Part 4: Application of Weibull distribution function to neutralization of dihydroxyaluminum sodium carbonate

The rate of neutralization of hydrochlorid acid by dihydroxyaluminum sodium carbonate (DHASC) has been studied by pH-stat method. The neutralization process was examined by monitoring the appearance of aluminum and sodium ions in the reaction medium. The Weibull distribution function was applied to the quantitative interpretation of neutralization rate data. All mathematically meaningful parameters derived from this distribution function were useful for consideration of the mechanism according to which the neutralization of DHASC occurs.

Studies of neutralizing properties of antacid preparations. Part 3: Constant pH neutralization of hydrochloric acid by hydrotalcite

The neutralization reaction of hydrochloric acid by powdered hydrotalcite (HT) was studied by pH-stat method in the range of pH from 3.0 to 4.8. The neutralization process was examined by monitoring the appearance of aluminium and magnesium ions in the reaction medium, by determination of the chloride concentration in solution and by IR analysis of partially neutralized HT. The mechanism of acid neutralization of HT is discussed.

Effect of composition on the neutralizing properties of antacid preparations

11 antacid mixtures made up to simulate the preparations available on the market were prepared. These mixtures contain aluminium hydroxide gel, calcium carbonate, magnesium hydroxide and magnesium trisilicate. The antacid properties of the mixtures obtained were characterized by total acid consuming capacity, rate of neutralization and duration of action. It was indicated that the composition of the mixtures influenced their neutralizing properties; an interaction between constituents of these preparations was noted.

Preparation of drugs used in hyperacidity. Part IV. Effect of sulphate, chloride and nitrate ions and mannitol on neutralizing properties and changes of alumina gels

The stability of alumina gels precipitated from the appropriate aluminum salts with ammonia solution have been investigated. The effect of SO42-, Cl-, NO3-ions and mannitol on this stability was evaluated. SO42-ions, and to a lesser degree also Cl- and NO3-ions stabilize alumina gel due to the incorporation in its structure. The use of mannitol solution as a suspension medium results also in the complete stabilization of the gel.

Preparation of drugs used in hyperacidity. Part III. Stability of alumina gels

The effect of temperature on the stability of alumina gels heated in the solid state and in the suspension was investigated. The suspensions were made in water, 1,4-dioxane and their mixture. It was found that the ageing of gels occurs during heating them in the solid state, in water and water-dioxane mixture as a first order reaction. The neutralizing properties of gel heated in 100% dioxane were not changed. The phase analysis of the investigated preparations was based on X-ray measurements. The contribution of water in the mechanism of gel changes is discussed.

Preparation of drugs used in hyperacidity. Part I. Effects of pH of precipitation on the neutralizing properties of alumina gels

Alumina gels were obtained from sodium aluminate by addition of 3 N HNO3, HCl or H2SO4 solutions or by saturation with gaseous CO2. The effect of several physicochemical factors (pH of precipitation, kind and concentration of precipitating agent, temperature) on the neutralizing properties of the obtained forms of Al(OH)3 was investigated. The linear correlation between the pH of precipitation and the neutralizing properties was found. The effect of different precipitating anions on the acid-consuming capacity and the rate of neutralization of 0-1 N HCl was established.