Acids In Biological Fluids Research Articles

Diagnostic analysis of toxic damage due to a dose of zoledronic acid

Introduction: Comprehensive analysis is necessary to analyze the widespread use of bisphosphonate drugs in the treatment and prevention of various diseases of connective tissue structures. The relevance of the study depends on the impact they have on the patient’s somatic condition, given the number of early and late complications diagnosed by domestic and foreign clinicians.
 Materials and methods: The methodology used was developed on Stavropol Regional Clinical Hospital from 2010 to 2022. A randomized and observational study of the state of connective tissue structures was conducted in 186 patients who had a history of taking zoledronic acid and developed bisphosphonate osteonecrosis of the jawbone. At the diagnostic and treatment stages, patients were tested using laboratory methods to monitor amino acids in biological fluids (blood), as well as bone blocks extracted intraoperatively using highly effective gas-liquid chromatography on AAA 500.
 Results and discussion: Aminograms obtained in the pre-operative period indicate toxic effects of zoledronic acid on neuro, endocrine, and other human systems. The initiation and progression of aseptic inflammatory processes in tissue structures is correlated with the deteriorating general ocular status of patients when amino acids, such as alanine, serine, taurine, phenylalanine, tyrosine, proline, histidine, glycine, and valine, against a background of 90.4±2.1 mmol/L ammonia are reduced critically.
 Conclusion: Zoledronic acid initiates an aseptic chronic inflammatory process in the jaw bones, accompanied by toxic acidosis, which worsens osteoporotic symptoms.

Clinical significance of measuring fatty acids in biological fluids of dairy cows (in blood and milk) with a focus on heat stress

Fatty acids (FA) have a variety of functions in animal bodies. They can be used as metabolic biomarkers, including in pathological conditions. Heat stress (HS) is accompanied by a drop in productivity in dairy cows, resulting from a negative energy balance (NEB), impaired biochemical processes in the body and suppressed immune system. The paper describes the role of individual FAs, the changes in content and ratio of which in serum and milk can be used to assess the physiological state or to predict HS in dairy cows. The purpose of the review has been to show the prospects in the study of the fatty acid composition of biological fluids (blood and milk) to assess the clinical status of dairy cows under HS and the consequences of the possible impact of heat on dairy product quality. Dietary strategies to correct the body's clinical status through dietary FAs have also been mentioned in this literature review.

Antifouling lipid membrane coupled with silver nanoparticles for electrochemical detection of nucleic acids in biological fluids

Electrochemical method capable of detecting specific nucleic acids in complex fluid will undoubtedly advance the diagnosis of many kinds of diseases. Herein, by coupling lipid membrane with silver nanoparticles (AgNPs), we develop a new electrochemical method for sensitive and reliable detection of nucleic acids in biological fluids. The advantages of lipid membrane especially its excellent antifouling ability is employed to enhance the applicability of the method in complex environment; while the significant solid-state Ag/AgCl response of AgNPs is used to ensure the detection sensitivity of the method. The core of this method's workflow is the target-induced Y-shape structure formation, which results in the recruitment of AgNPs to the electrode surface, producing considerable electrochemical responses used for target nucleic acid detection. Taking highly upregulated in liver cancer (HULC), a liver cancer-related long non-coding RNA as a model target, the method exhibits high sensitivity, specificity, and reproducibility with a detection limit of 0.42 fM. Moreover, the method displays desirable usability in biological fluids such as serum, which will be of great potential in clinical diagnosis.

A Novel Luminescent Metal‐Organic Framework as a Remarkable Sensor for Detecting Aristolochic Acids in Biological Fluids

AbstractAbstract: Aristolochic acids (AAs) have caused widespread concern as highly nephrotoxic and carcinogenic substances. Therefore, it is essential to explore a simple and feasible method to detect AAs for disease prevention and clinical diagnosis. In this work, we designed and synthesized a novel luminescent metal organic framework (Zn‐MOF), which has excellent structural stability and fluorescence stability. Notably, the luminescent Zn‐MOF exhibits strong blue emission owing to ligand‐centered electronic transitions, while being capable as a selective sensor for the quantitative detection of AAs in biological fluids with low detection limit. The fluorescence analysis method, possessing the advantages of reliability and high accuracy, further demonstrated that Zn‐MOF has potential applications in monitoring the carcinogen biomarker AAs. Moreover, a paper‐based sensor has been devised by depositing Zn‐MOF on filter paper, which provides a novel strategy for visual, rapid, and on‐site AAs detection with the naked eye.

Abnormalities in subsets of B and T cells in Mexican patients with inborn errors of propionate metabolism: observations from a single-center case series.

Propionate inborn errors of metabolism (PIEM), including propionic (PA) and methylmalonic (MMA) acidemias, are inherited metabolic diseases characterized by toxic accumulation of propionic, 3-hydroxypropionic, methylcitric, and methylmalonic organic acids in biological fluids, causing recurrent acute metabolic acidosis events and encephalopathy, which can lead to fatal outcomes if managed inadequately. PIEM patients can develop hematological abnormalities and immunodeficiency, either as part of the initial clinical presentation or as chronic complications. The origin and characteristics of these abnormalities have been studied poorly. Thus, the aim of the present work was to evaluate and describe lymphoid, myeloid, and erythroid cell population profiles in a group of clinically stable PIEM patients. This was a retrospective study of 11 nonrelated Mexican PIEM patients. Clinical, biochemical, nutritional, hematological, and lymphocyte subsets were analyzed. Despite being considered clinically stable, 91% of patients had hematological or immunological abnormalities. The absolute lymphocyte subset counts were low in all patients but one, with CD4+ T-cell lymphopenia, being the most common one. Furthermore, of the 11 studied subjects, nine presented with a low CD4/CD8 ratio. Among the observed hematological alterations, bicytopenia was the most common (82%) one, followed by anemia (27%). Our results contribute to the landscape of immunological abnormalities observed previously in PIEM patients; these abnormalities can become a life-threatening chronic complications because of the increased risk of opportunistic diseases. These findings allow us to propose the inclusion of monitoring immune biomarkers, such as subsets of lymphocytes in the follow up of PIEM patients.

Amplification-free profiling of microRNA-122 biomarker in DILI patient serums, using the luminex MAGPIX system

Dynamic chemical labelling is a single-base specific method to enable detection and quantification of micro-Ribonucleic Acids in biological fluids without extraction and pre-amplification. In this study, dynamic chemical labelling was combined with the Luminex MAGPIX system to profile levels of microRNA-122 biomarker in serum from patients with Drug-Induced Liver Injury.

Two clinical cases of glutaric aciduria type I in the Republic of Bashkortostan

Glutaric aciduria type I is an autosomal recessive disease caused by mutations in the GCDH gene, which encodes the glutaryl-CoA-dehydrogenase enzyme. A lack of this enzyme leads to the accumulation of glutaric and 3-OH-glutaric (3-hydroxyglutaric) acids in biological fluids and tissues, which have a neurotoxic effect primarily on subcortical brain structures. We present two clinical cases of glutaric aciduria type I in children diagnosed after developing neurological symptoms. One patient had acute disease onset in the form of an encephalopathic crisis, which is typical for most clinical cases of the disease. The other patient developed subacute symptoms. Generalized dystonic hyperkinesia was a key sign of the disease in both patients. Information from the medical history and clinical presentation, together with the neuroimaging results, enabled us to suspect the right diagnosis and to confirm it using biochemical and then molecular genetic tests. In both cases, despite diet therapy using a specialized medicinal product, the patients continued to have motor disturbances.

Homocyclic o-dicarboxaldehydes: Derivatization reagents for sensitive analysis of amino acids and related compounds by capillary and microchip electrophoresis.

Amino acids are essential compounds for living organisms, and their determination in biological fluids is crucial for the clinical analysis and diagnosis of many diseases. However, the detection of most amino acids is hindered by the lack of a strong chromophore/fluorophore or electrochemically active group in their chemical structures. The highly sensitive determination of amino acids often requires derivatization. Capillary electrophoresis is a separation technique with excellent characteristics for the analysis of amino acids in biological fluids. Moreover, it offers the possibility of precapillary, on-capillary, or postcapillary derivatization. Each derivatization approach has specific demands in terms of the chemistry involved in the derivatization, which is discussed in this review. The family of homocyclic o-dicarboxaldehyde compounds, namely o-phthalaldehyde, naphthalene-2,3-dicarboxaldehyde, and anthracene-2,3-dicarboxaldehyde, are powerful derivatization reagents for the determination of amino acids and related compounds. In the presence of suitable nucleophiles they react with the primary amino group to form both fluorescent and electroactive derivatives. Moreover, the reaction rate enables all of the derivatization approaches mentioned above. This review focuses on articles that deal with using these reagents for the derivatization of amino acids and related compounds for ultraviolet-visible spectrometry, fluorescence, or electrochemical detection. Applications in capillary and microchip electrophoresis are summarized and discussed.

Developing a point-of-care System for Determination of Dopamine, Ascorbic and Uric Acids in Biological Fluids Using a Screen-Printed Electrode Modified by Three Dimensional Graphene/Carbon Nanotube Hybrid

Developing a point-of-care System for Determination of Dopamine, Ascorbic and Uric Acids in Biological Fluids Using a Screen-Printed Electrode Modified by Three Dimensional Graphene/Carbon Nanotube Hybrid

Chiral Capillary Electrophoresis-Mass Spectrometry.

Capillary electrophoresis (CE) is a well-established and one of the most powerful separation techniques in the field of chiral separations. Its hyphenation with mass spectrometry (MS) combines both the high separation efficiency and low sample consumption of CE and the high sensitivity and structural information of MS. Thus, the outstanding chiral resolution power of CE along with the MS advantages makes CE-MS a perfect combination to achieve sensitive enantioseparations. This chapter describes three representative examples of different approaches used in the chiral analysis of amino acids in biological fluids by CE-MS. The first methodology uses the partial filling technique to avoid the entry of cyclodextrins in the MS source. The second method shows the possibility to carry out the direct coupling EKC-MS even when a relative high concentration of a native cyclodextrin is used as chiral selector. The last example illustrates an alternative strategy based on the formation of stable diastereomers between an enantiomerically pure chiral reagent and the amino acids enantiomers which can be separated in an achiral environment.

Identification of novel bile acids as biomarkers for the early diagnosis of Niemann-Pick C disease.

This article describes a rapid UPLC‐MS/MS method to quantitate novel bile acids in biological fluids and the evaluation of their diagnostic potential in Niemann‐Pick C (NPC). Two new compounds, NPCBA1 (3β‐hydroxy,7β‐N‐acetylglucosaminyl‐5‐cholenoic acid) and NPCBA2 (probably 3β,5α,6β‐trihydroxycholanoyl‐glycine), were observed to accumulate preferentially in NPC patients: median plasma concentrations of NPCBA1 and NPCBA2 were 40‐ and 10‐fold higher in patients than in controls. However, NPCBA1 concentrations were normal in some patients because they carried a common mutation inactivating the GlcNAc transferase required for the synthesis of this bile acid. NPCBA2, not containing a GlcNAc moiety, is thus a better NPC biomarker.

Evidence that 3-hydroxy-3-methylglutaric and 3-methylglutaric acids induce DNA damage in rat striatum.

3-Hydroxy-3-methylglutaryl-CoA lyase (HL) deficiency is a rare autosomal recessive disorderaffecting the final step of leucine degradation and ketogenesis and biochemically characterized by the predominant accumulation of 3-hydroxy-3-methylglutaric (HMG) and 3-methylglutaric (MGA) acids in biological fluids and tissues of affected patients. Considering that previous studies reported that HMG and MGA have pro oxidant properties, the present study evaluated the ex vivo and in vitro effects of HMG and MGA on frequency and index of DNA damage in cerebral cortex and striatum of young rats. The ex vivo effects of both organic acids on 8-hydroxy-2'-deoxyguanosine (OHdG) levels and their in vitro effects on 2',7'-dichlorofluorescin (DCFH) oxidation and glutathione (GSH) concentrations in rat striatum were also determined. We also investigated the ex vivo effects of both organic acids on 8-hydroxy-2'-deoxyguanosine (OHdG) levels in rat striatum. In the ex vivo experiments, DNA damage was determined in striatum homogenates prepared 30min after a single intrastriatal administration of HMG or MGA. On the other hand, the in vitro evaluation was performed after an incubation of rat cerebral cortex or striatum homogenates or slices in the presence of HMG or MGA during 1h at 37°C. We observed that the intrastriatal administration of HMG and MGA increased the frequency and the index of DNA damage, as well as OHdG staining in rat striatum. We also verified that MGA, but not HMG, increased DNA damage frequency and index in vitro in striatum of rats. In contrast, no alterations were verified in vitro in cerebral cortex. Finally, we found that HMG and MGA increased DCFH oxidation and decreased GSH concentrations in rat striatum. Therefore, it may be presumed that DNA damage provoked by HMG and MGA possibly via reactive species generation is involved, at least in part, in the pathophysiology of brain injury, particularly in the striatum of HL-deficient patients.

Tailoring the surface of liquid crystal droplets with chitosan/surfactant complexes for the selective detection of bile acids in biological fluids

The surface of 5CB droplets dispersed in aqueous solution is tailored by the adsorption of CHI/SC14S complexes at the 5CB/aqueous interface. The CHI/SC14S complex-coated 5CB droplets can be used as an optical probe to detect CA in biological fluids without dilution.

Application of solid phase microextraction for quantitation of polyunsaturated fatty acids in biological fluids.

Development of a straightforward strategy for simultaneous quantitative analysis of nonesterified fatty acids (NEFA) species in biofluids is a challenging task because of the extreme complexity of fatty acid distribution in biological matrices. In this study, we present a direct immersion solid phase microextraction method coupled to a liquid chromatography-mass spectrometry platform (DI-SPME- HPLC-ESI -MS) for determination of unconjugated fatty acids (FA) in fish and human plasma. The proposed method was fully validated according to bioanalytical method validation guidelines. The LOD and LOQ were in the range of 0.5-2 and 5-12 ng/mL, respectively, with a linear dynamic range of 100 fold for each compound. Absolute and relative matrix effects were comprehensively evaluated and found to be in the acceptable range of 91-116%. The affinity constant (Ka) of individual FAs to protein albumin was determined to be 9.2 × 10(4) to 4.3 × 10(5) M(-1). The plasma protein binding (PPB%) was calculated and found to be in the range of 98.0-99.7% for different polyunsaturated fatty acids (PUFAs). The PUFAs under study were found at a high concentration range in fish plasma, whereas only a few were within quantification range in control human plasma. The method was successfully applied for monitoring PUFA changes during the operation in plasma samples obtained from patients undergoing cardiac surgery with the use of cardiopulmonary bypass (CPB). The most significant contribution induced by surgery was noticed in the concentration level of α-linolenic acid (18:3, ALA), arachidonic acid (20:4, AA), and docosahexanoic acid (22:6, DHA) soon after administration of CPB in all cases.

Circulating and stool nucleic acid analysis for colorectal cancer diagnosis.

In recent years, the need to identify molecular markers characterized by high sensitivity and specificity in detecting and monitoring early and colorectal cancer lesions has increased. Up to now, none of the markers or panels of markers analyzed have met the rigorous standards required of a screening program. The important discovery of circulating nucleic acids in biological fluids has aroused intense scientific interest because of their usefulness in malignant and non malignant diseases. Over time, their yield and stability have been identified and compared with other "standard" biomarkers. The analysis of circulating DNA from blood and stool is a relatively simple and non-invasive procedure, representing a very attractive marker to detect genetic and epigenetic mutations and to monitor disease progression. A correlation between blood and stool biomarkers could also help to enhance currently available diagnostic approaches. However, various processing and analytic problems need to be resolved before such an approach can be applied in clinical practice.

Direct Detection of Amino Acids Using Extractive Electrospray Ionization Tandem Mass Spectrometry

Abstract A novel method was developed for the direct detection of amino acids in biological fluids by extractive electrospray ionization (EESI) tandem mass spectrometry (MS) with minimal sample pretreatment. Based on our previous research, a novel EESI ion source was constructed to improve analytical performance and operation safety. The EESI-MS conditions were optimized using representative amino acid standards. The methanol-water reagent solvent (1:1, v/v) was electrosprayed at 5 μL min−1 at a high voltage (+4 kV, positive ion detection mode). The temperature of the heated capillary was optimized to be 150 °C. Collision induced dissociation (CID) experiments were performed by applying 17%−25% of the collision energy to the precursor ions isolated with a window width of 1.5 mass/charge (m/z) units. The limit of detection (LOD) for these amino acids was in the range of 0.14−26.2 μg L−1, and the linear dynamic range was larger than two orders of magnitude. The average time for a single amino acid analysis using a typical human urine sample was less than 0.5 min. The recovery rates for different concentrations of amino acids ranged from 82.6% to 105.6%, and the relative standard deviations (RSD) ranged from 2.2% to 11.4%. The results showed that EESI-MS is a powerful tool for the rapid, sensitive, and quantitative detection of amino acids in complex biological samples.

Rapid quantification of conjugated and unconjugated bile acids and C27 precursors in dried blood spots and small volumes of serum

The aim of the study was to develop a method for fast and reliable diagnosis of peroxisomal diseases and to facilitate differential diagnosis of cholestatic hepatopathy. For the quantification of bile acids and their conjugates as well as C(27) precursors di- and trihydroxycholestanoic acid (DHCA, THCA), in small pediatric blood samples we combined HPLC separation on a reverse-phase C18 column with ESI-MS/MS analysis in the negative ion mode. Analysis was done with good precision (CV 3,7%-11.1%) and sufficient sensitivity (LOQ: 11-91 nmol/L) without derivatization. Complete analysis of 17 free and conjugated bile acids from dried blood spots and 10 microL serum samples, respectively, was performed within 12 min. Measurement of conjugated primary bile acids plus DHCA and THCA as well as ursodeoxycholic acid was done in 4.5 min. In blood spots of healthy newborns, conjugated primary bile acids were found in the range of 0.01 to 2.01 micromol/L. Concentrations of C(27) precursors were below the detection limit in normal controls. DHCA and THCA were specifically elevated in cases of peroxysomal defects and one Zellweger patient.

Bile acids: analysis in biological fluids and tissues.

The formation of bile acids/bile alcohols is of major importance for the maintenance of cholesterol homeostasis. Besides their functions in lipid absorption, bile acids/bile alcohols are regulatory molecules for a number of metabolic processes. Their effects are structure-dependent, and numerous metabolic conversions result in a complex mixture of biologically active and inactive forms. Advanced methods are required to characterize and quantify individual bile acids in these mixtures. A combination of such analyses with analyses of the proteome will be required for a better understanding of mechanisms of action and nature of endogenous ligands. Mass spectrometry is the basic detection technique for effluents from chromatographic columns. Capillary liquid chromatography-mass spectrometry with electrospray ionization provides the highest sensitivity in metabolome analysis. Classical gas chromatography-mass spectrometry is less sensitive but offers extensive structure-dependent fragmentation increasing the specificity in analyses of isobaric isomers of unconjugated bile acids. Depending on the nature of the bile acid/bile alcohol mixture and the range of concentration of individuals, different sample preparation sequences, from simple extractions to group separations and derivatizations, are applicable. We review the methods currently available for the analysis of bile acids in biological fluids and tissues, with emphasis on the combination of liquid and gas phase chromatography with mass spectrometry.

Immune cell membrane fatty acids and inflammatory marker, C-reactive protein, in patients with multiple sclerosis

Measurement of fatty acids in biological fluids and cell membranes including leucocytes from multiple sclerosis patients is inconsistent. The objective of the present study was to investigate the fatty acid composition within the different membrane phospholipid fractions in peripheral blood mononuclear cells in multiple sclerosis patients, and correlate with severity of neurological outcome as measured by the Kurtzke Expanded Disability Status Scale and Functional System Scores. The fatty acid composition of phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, sphingomyelin and phosphatidylinositol phospholipids in the peripheral blood mononuclear cells of twenty-six multiple sclerosis and twenty-five control subjects were measured by GC, and C-reactive protein was measured in all subjects. The elongation product of 20 : 4n-6, 22 : 4n-6, was significantly decreased in membrane phosphatidylethanolamine and phosphatidylserine in multiple sclerosis patients (P = 0.01 and P = 0.03 respectively), and correlated inversely with severity of disease and C-reactive protein. Also an inverse correlation was observed between the C-reactive protein and membrane phosphatidylcholine and phosphatidylserine 20 : 4n-6. Cultural and ethnic differences, as well as dietary variability, especially in a diseased state have been implicated in the differences observed in the fatty acid composition in peripheral blood mononuclear cell membranes of patients with multiple sclerosis. The present results suggest that the disease state may in part explain the reported inconsistencies in fatty acid levels in multiple sclerosis patients.

Two Mass-Spectrometric Techniques for Quantifying Serine Enantiomers and Glycine in Cerebrospinal Fluid: Potential Confounders and Age-Dependent Ranges

The recent discovery and specific functions of D-amino acids in humans are bound to lead to the revelation of D-amino acid abnormalities in human disorders. Therefore, high-throughput analysis techniques are warranted to determine D-amino acids in biological fluids in a routine laboratory setting. We developed 2 chromatographic techniques, a nonchiral derivatization with chiral (chirasil-L-val column) separation in a GC-MS system and a chiral derivatization with Marfey's reagent and LC- MS analysis. We validated the techniques for D-serine, L-serine, and glycine determination in cerebrospinal fluid (CSF), evaluated several confounders, and determined age-dependent human concentration ranges. Quantification limits for D-serine, L-serine, and glycine in cerebrospinal fluid were 0.14, 0.44, and 0.14 micromol/L, respectively, for GC-MS and 0.20, 0.41, and 0.14 micromol/L for LC-MS. Within-run imprecision was <3% for both methods, and between-run imprecision was <13%. Comparison of both techniques with Deming regression yielded coefficients of 0.90 (D-serine), 0.92 (L-serine), and 0.96 (glycine). Sample collection, handling, and transport is uncomplicated-there is no rostrocaudal CSF gradient, no effect of storage at 4 degrees C for 1 week before storage at -80 degrees C, and no effect of up to 3 freeze/thaw cycles. Conversely, contamination with erythrocytes increased D-serine, L-serine, and glycine concentrations. CSF concentrations for 145 apparently healthy controls demonstrated markedly and specifically increased (5 to 9 times) D-serine concentrations during early central nervous system development. These 2 clinically applicable analysis techniques will help to unravel pathophysiologic, diagnostic, and therapeutic issues for disorders associated with central nervous system abnormalities, NMDA-receptor dysfunction, and other pathology associated with D-amino acids.