Pharmacokinetics, tissue distribution, bioavailability and excretion of the anti-virulence drug Fluorothiazinon in rats and rabbits.

Growing antimicrobial resistance has accelerated the development of anti-virulence drugs to suppress bacterial toxicity without affecting cell viability. Fluorothiazinon (FT), an anti-virulence, type three secretion system and flagella motility inhibitor which has shown promise to suppress drug-resistant pathogens having the potential to enhance the efficacy of commonly prescribed antibiotics when used in combination. In this study we characterized the pharmacokinetics, tissue distribution, bioavailability and excretion of FT in rats and rabbits. FT presented a dose-proportional linear increase in the blood of rats. Tissue distribution profiling confirmed that FT distributes to all organs being substantially higher than in the blood of rats. The bioavailability of FT was higher when administered with starch than with water implying FT should be ideally dosed with food. FT was primarily excreted in the feces in rats and rabbits while negligible amounts are recovered from the urine.

Chitosan derivatives as dynamic coatings for transferrin glycoform separation in capillary electrophoresis.

Chitosan and its derivatives are interesting biopolymers for different field of analytical chemistry, especially in separation techniques. The present study was aimed at testing chitosan water soluble derivatives as dynamic coating agents for application to capillary electrophoresis. In particular, chitosan was modified following three different chemical reactions (nucleophilic substitution, reductive amination, and condensation) to introduce differences in charge and steric hindrance, and to assess the effect of these physico-chemical properties in capillary electrophoresis. The effects were tested on the capillary electrophoretic separation of the glycoforms of human transferrin, an important iron-transporting serum protein, one of which, namely disialo-transferrin (CDT), is a biomarker of alcohol abuse. Chitosan derivatives were characterized by using NMR and 1H NMR, HP-SEC-TDA, DLS, and rheology. The use of these compounds as dynamic coatings in the electrolyte running buffer in capillary electrophoresis was tested assessing the peak resolution of the main glycoforms of human transferrin and particularly of disialo-transferrin. The results showed distinct changes of the peak resolution produced by the different derivatives. The best results in terms of peak resolution were achieved using polyethylene glycol (PEG)-modified chitosan, which, in comparison to a reference analytical approach, provided an almost baseline resolution of disialo-transferrin from the adjacent peaks.

Chitosan Film Sensor for Ammonia Detection in Microdiffusion Analytical Devices.

Chitosan films have attracted increased attention in the field of sensors because of chitosan's unique chemico-physical properties, including high adsorption capacity, filmability and transparency. A chitosan film sensor was developed through the dispersion of an ammonia specific reagent (Nessler's reagent) into a chitosan film matrix. The chitosan film sensor was characterized to assess the film's properties by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). A gas diffusion device was prepared with the chitosan film sensor, enabling the collection and detection of ammonia vapor from biological samples. The chitosan film sensor color change was correlated with the ammonia concentration in samples of human serum and artificial urine. This method enabled facile ammonia detection and concentration measurement, making the sensor useful not only in clinical laboratories, but also for point-of-care devices and wherever there is limited access to modern laboratory facilities.

Study of metabolism and potential toxicity of nine synthetic opioid analogs using the zebrafish larvae model.

The use of novel psychoactive substances (NPSs) has dramatically increased worldwide, and among them, synthetic opioids are one of the fastest growing groups, where cinnamylpiperazines and 2-benzylbenzimidazoles represent two of the most relevant subclasses. However, the data on their toxicity and metabolism are still limited. The aim of the present study was to evaluate the toxicity and metabolic pathways of some compounds belonging to these families, namely, AP-237, 2-methyl AP-237, isotonitazene, flunitazene, etodesnitazene, metonitazene, metodesnitazene, N-pyrrolidino etonitazene, and butonitazene. The study was performed using a zebrafish early life stages model. In fact, zebrafish (Danio rerio) embryos and larvae have recently been recognized as a suitable animal model in alternative to mammals, because they require less time and resources and do not need complex procedures for ethics approval. The cellular toxicity after a single administration was assessed at the fourth day post-fertilization with acridine orange staining. Possible morphological defects were evaluated with a light microscope after 24 h of exposure to 1 µmol/L concentration of each drug. Subsequently, the larvae were euthanized and underwent analysis of drug metabolites using UPLC coupled to an Orbitrap high-resolution mass spectrometer. High rates of morphological defects, as well as of cellular death, were detected, but no significant difference in mortality between treatment and control groups was observed. In addition, several metabolites, mainly produced through monohydroxylation, N-dealkylation, and O-dealkylation, were identified in the larvae extracts.

Pharmacokinetics, quorum-sensing signal molecules and tryptophan-related metabolomics of the novel anti-virulence drug Fluorothiazinon in a Pseudomonas aeruginosa-induced pneumonia murine model.

Pseudomonas aeruginosa (PA) infection is commonly associated with hospital-acquired infections in patients with immune deficiency and/or severe lung diseases. Managing this bacterium is complex due to drug resistance and high adaptability. Fluorothiazinon (FT) is an anti-virulence drug developed to suppress the virulence of bacteria as opposed to bacterial death increasing host's immune response to infection and improving treatment to inhibit drug resistant bacteria. We aimed to evaluate FT pharmacokinetics, quorum sensing signal molecules profiling and tryptophan-related metabolomics in blood, liver, kidneys, and lungs of mice. Study comprised three groups: a group infected with PA that was treated with 400 mg/kg FT ("infected treated group"); a non-infected group, but also treated with the same single drug dose ("non-infected treated group"); and an infected group that received a vehicle ("infected non-treated group"). PA-mediated infection blood pharmacokinetics profiling was indicative of increased drug concentrations as shown by increased Cmax and AUCs. Tissue distribution in liver, kidneys, and lungs, showed that liver presented the most consistently higher concentrations of FT in the infected versus non-infected mice. FT showed that HHQ levels were decreased at 1 h after dosing in lungs while PQS levels were lower across time in lungs of infected treated mice in comparison to infected non-treated mice. Metabolomics profiling performed in lungs and blood of infected treated versus infected non-treated mice revealed drug-associated metabolite alterations, especially in the kynurenic and indole pathways.

Application of Paper-Based Microfluidic Analytical Devices (µPAD) in Forensic and Clinical Toxicology: A Review.

The need for providing rapid and, possibly, on-the-spot analytical results in the case of intoxication has prompted researchers to develop rapid, sensitive, and cost-effective methods and analytical devices suitable for use in nonspecialized laboratories and at the point of need (PON). In recent years, the technology of paper-based microfluidic analytical devices (µPADs) has undergone rapid development and now provides a feasible, low-cost alternative to traditional rapid tests for detecting harmful compounds. In fact, µPADs have been developed to detect toxic molecules (arsenic, cyanide, ethanol, and nitrite), drugs, and drugs of abuse (benzodiazepines, cathinones, cocaine, fentanyl, ketamine, MDMA, morphine, synthetic cannabinoids, tetrahydrocannabinol, and xylazine), and also psychoactive substances used for drug-facilitated crimes (flunitrazepam, gamma-hydroxybutyric acid (GHB), ketamine, metamizole, midazolam, and scopolamine). The present report critically evaluates the recent developments in paper-based devices, particularly in detection methods, and how these new analytical tools have been tested in forensic and clinical toxicology, also including future perspectives on their application, such as multisensing paper-based devices, microfluidic paper-based separation, and wearable paper-based sensors.

PMI estimation through metabolomics and potassium analysis on animal vitreous humour.

INTRODUCTION: The estimation of post-mortem interval (PMI) remains a major challenge in forensic science. Most of the proposed approaches lack the reliability required to meet the rigorous forensic standards. OBJECTIVES: We applied 1H NMR metabolomics to estimate PMI on ovine vitreous humour comparing the results with the actual scientific gold standard, namely vitreous potassium concentrations. METHODS: Vitreous humour samples were collected in a time frame ranging from 6 to 86 h after death. Experiments were performed by using 1H NMR metabolomics and ion capillary analysis. Data were submitted to multivariate statistical data analysis. RESULTS: A multivariate calibration model was built to estimate PMI based on 47 vitreous humour samples. The model was validated with an independent test set of 24 samples, obtaining a prediction error on the entire range of 6.9 h for PMI < 24 h, 7.4 h for PMI between 24 and 48 h, and 10.3 h for PMI > 48 h. Time-related modifications of the 1H NMR vitreous metabolomic profile could predict PMI better than potassium up to 48 h after death, whilst a combination of the two is better than the single approach for higher PMI estimation. CONCLUSION: The present study, although in a proof-of-concept animal model, shows that vitreous metabolomics can be a powerful tool to predict PMI providing a more accurate estimation compared to the widely studied approach based on vitreous potassium concentrations.

Hair analysis as a new tool to monitor adherence to long-term therapy to statins.

Statins are cholesterol-lowering medications which are widely prescribed as first-line treatment for hyperlipidemia, against high blood cholesterol aimed at reducing the risk of atherosclerotic diseases. Notwithstanding their undoubted efficacy, the needed long-term treatment with these drugs is characterized by a high percentage of dropout. Consequently, an effective tool to verify the patients' compliance to statin therapy is needed. In this context, the analysis for drugs and drug metabolites in the hair may represent an almost ideal tool because, according to a sound body of forensic toxicological literature, concentrations in the hair matrix reflect the chronic intake of drugs and pharmaceuticals. In this light, in the present study, a novel, specific and sensitive ultra-performance liquid chromatography-tandem mass spectrometry method has been developed to determine six statins and their metabolites (namely atorvastatin, (p)α-OH-atorvastatin-lactone, (o)α-OH-atorvastatin-lactone, rosuvastatin, N-desmethyl rosuvastatin and pravastatin) in human hair. After optimization, the method was successfully validated in terms of selectivity, linearity, sensitivity, precision, accuracy, stability and matrix effect. Moreover, the practical applicability of this method for verifying adherence to statin therapy was assessed by testing samples of hair collected from subjects under long-term therapy with statins.

Validation of a New Salt-Assisted HS-GC-FID Method for the Determination of Ethanol in the Vitreous Humor.

Headspace gas chromatography with a flame ionization detector (HS-GC-FID) is a well-established approach for determining blood alcohol concentration, including in cadaveric specimens. Although the integrity of blood specimens can be adequately guaranteed after the sampling, the quantification of ethanol in cadaveric blood can be affected by postmortem fermentative phenomena occurring between the time since death and the sampling of biofluids. The vitreous humor is less affected by putrefactive phenomena allowing compound determination and its use as an alternative biological matrix. The present work aimed to develop and validate a method using the salting-out effect and based on HS-GC-FID for the determination of ethanol in the vitreous humor. The reported analytical method is based on a simple vitreous humor pre-treatment consisting of a dilution (1:9) with a solution of 2.5 mol/L K2CO3 and 0.0012 mol/L tert-butanol (internal standard). After 1 min of incubation, part of the specimen evaporated in the headspace (2,000 µL) is injected into the chromatographic system and analyzed in isothermal mode (40°C), with a chromatographic time of 1.6 min. The method was validated in terms of selectivity, the lowest limit of detection, intraday and total imprecision, and trueness (bias). The determination of ethanol in the vitreous humor and blood was carried out in 75 cases. The correlation between the two matrices was confirmed in 61 cases. However, 14 vitreous humor specimens showed lower ethanol concentrations, and in the related blood specimens, it was possible to identify the signal of n-propanol, a typical product of postmortem microbial fermentation, that justifies the excess of ethanol in the blood specimens.

Development and Validation of a Rapid Method for Identification of New Synthetic Cannabinoids in Hair Based on High-Performance Liquid Chromatography-Ion Trap Mass Spectrometry Using a Simplified User Interface.

The penetration of the new psychoactive substances (NPSs) into the market of clandestine drugs is highly dynamic, causing potentially false-negative results using the current analytical instrumentation, particularly in the screening phase. At present, the suggested approach to perform a comprehensive screening requires the use of high-resolution mass spectrometry (MS) with associated high costs of purchase and maintenance and need of skilled and dedicated personnel. Here we describe the development and validation of a simplified approach based on a high-performance liquid chromatography-ion trap MS system with a user-friendly interface dedicated to toxicological analysis. The system, originally intended for a broad toxicological screening, was tuned to identify new synthetic cannabinoids in hair. After a washing step with dichloromethane, hair (about 50 mg) was incubated for 3 h with 1.5 mL ethanol. One milliliter of this solution was then dried, reconstituted with mobile phase and injected. The peak identification was based on the chromatographic retention times and MS2/MS3 data using a database which included up to 158 NPSs. The method was validated according to international guidelines on a selected panel of NPSs, namely methyl 2-[[1-(5-fluoropentyl)indazole-3-carbonyl]amino]-3,3-dimethylbutanoate (5F-ADB), 1-Pentyfluoro-1H-indole-3-carboxylic acid 8-quinolinyl ester (5F-PB 22), N-[(2S)-1-amino-3-methyl-1-oxobutan-2-yl]-1-(5-chloropentyl)indazole-3-carboxamide (5Cl-AB-PINACA), (S)-N-(1-amino-1-oxo-3-phenylpropan-2-yl)-1-(5-fluoropentyl)-1H-indole-3-carboxamide [5F-APP-PICA (PX-1)],: (R)-N-(1-amino-1-oxo-3-phenylpropan-2-yl)-1-(5-fluoropentyl)-1H-indazole-3-carboxamide [5F-APP-PINACA (PX-2)], N-[(2S)-1-Amino-3-methyl-1-oxobutan-2-yl]-1-(cyclohexylmethyl)indazole-3-carboxamide (AB-CHMINACA), N-[(2S)-1-Amino-3-methyl-1-oxobutan-2-yl]-1-[(4-fluorophenyl)methyl] indazole-3-carboxamid (AB-FUBINACA), methyl (2S)-2-[[1-(cyclohexylmethyl)indole-3-carbonyl]amino]-3,3-dimethylbutanoate (MDMB-CHMICA), (S)-Methyl 2-(1-(5-fluoropentyl)-1H-indole-3-carboxamido)-3-methylbutanoate (MMB-2201) and (1-pentylindol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone (UR-144). The tested analytical method showed detection limits between 0.065 and 0.125 ng/mg. The intraday imprecision of the method showed average values within the range of 7.3-20%. The estimation of the trueness (bias) of method showed average values within the range of 1.5-12.3%. The analytical performance was also successfully assessed by four proficiency test samples containing NPS. No synthetic cannabinoids were detected in application to 82 hair samples from forensic cases previously analyzed with liquid chromatography-MS triple quadrupole.

Neutrophils inhibit γδ T cell functions in the imiquimod-induced mouse model of psoriasis.

Background: Psoriasis is a chronic skin disease associated with deregulated interplays between immune cells and keratinocytes. Neutrophil accumulation in the skin is a histological feature that characterizes psoriasis. However, the role of neutrophils in psoriasis onset and development remains poorly understood. Methods: In this study, we utilized the model of psoriasiform dermatitis, caused by the repeated topical application of an imiquimod containing cream, in neutrophil-depleted mice or in mice carrying impairment in neutrophil functions, including p47phox -/- mice (lacking a cytosolic subunit of the phagocyte nicotinamide adenine dinucleotide phosphate - NADPH - oxidase) and Sykfl/fl MRP8-cre+ mice (carrying the specific deletion of the Syk kinase in neutrophils only), to elucidate the specific contribution of neutrophils to psoriasis development. Results: By analyzing disease development/progression in neutrophil-depleted mice, we now report that neutrophils act as negative modulators of disease propagation and exacerbation by inhibiting gammadelta T cell effector functions via nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-mediated reactive oxygen species (ROS) production. We also report that Syk functions as a crucial molecule in determining the outcome of neutrophil and γδ T cell interactions. Accordingly, we uncover that a selective impairment of Syk-dependent signaling in neutrophils is sufficient to reproduce the enhancement of skin inflammation and γδ T cell infiltration observed in neutrophil-depleted mice. Conclusions: Overall, our findings add new insights into the specific contribution of neutrophils to disease progression in the IMQ-induced mouse model of psoriasis, namely as negative regulatory cells.

Contact Lens Wear Induces Alterations of Lactoferrin Functionality in Human Tears.

The tear film is a complex matrix composed of several molecular classes, from small metal ions to macromolecules. Contact lens (CL) wear can affect the protein homeostasis of the tear film, by accumulating deposits on the CL surface and/or altering their structural and functional properties. This work investigates the effect of CL wear on lactoferrin (Lf), one of the most abundant tear proteins, known as an unspecific biomarker of inflammation. Tears from eight volunteers were collected and analyzed after alternated periods of CL wear and without CL. The experimental approach is to probe Lf into unprocessed human tears by the peculiar fluorescence emission originating from complex formation of Lf with terbium (Tb3+) at the iron-binding sites. The experimental data indicate that CL wear does not significantly affect the total amount of Lf. On the other hand, Lf affinity for Tb3+ is reduced upon CL wear, suggesting relevant changes in Lf structure and possible alterations of protein functionality. Future studies based on this approach will help define CL features (material, lens-care solution, wearing time, etc.) with minimal effects on tear protein activity, in order to obtain more biocompatible and comfortable devices.

New evidence of high association between carbohydrate deficient transferrin (CDT) and alcohol-related road traffic accidents. A retrospective study on 929 injured drivers.

BACKGROUND: It is well known that traffic injuries still represent one of the main causes of death and that high blood alcohol concentrations while driving significantly increase the occurrence of accidents. However, only limited literature on the correlation between chronic alcohol abuse and accident risk is available. The aim of the present study was to investigate the hypothesis of an association between elevated concentrations of carbohydrate deficient transferrin (CDT) and the occurrence of alcohol-related traffic accidents. METHODS: The analytical determinations of BAC and CDT were performed following certified methods in HS-GC-FID and HPLC, respectively. For BAC, 0.50 g/L was used as cut-off, whereas 2.0% was used for CDT, according to the standardisation proposed by IFCC. A total of 929 drivers, tested for BAC at the time of hospital admission after a traffic accident, were classified into two groups: InjDr 1 (BAC ≤ 0.50 g/L) and InjDr 2 (BAC>0.50 g/L); all drivers were also tested for CDT. RESULTS: InjDr 1 included 674 individuals, only 2.5% showing a CDT above the cutoff, whereas InjDr 2 group consisted of 255 subjects, 28.6% testing positive for CDT (Odds Ratio 15.5). When subdividing the InjDr group into increasing classes of CDT, a steady increase in the percentage of BAC-positive drivers was appreciated. Moreover, average BAC was found to parallel each class of CDT. CONCLUSIONS: The reported data strongly support the use of CDT as a biomarker of increased risk of alcohol-related traffic accidents in the procedures of re-granting of the driving license upon confiscation for "drink driving".

Hair analysis for beta-blockers and calcium-channel blockers by using liquid chromatography-tandem mass spectrometry as a tool for monitoring adherence to antihypertensive therapy.

Adherence to therapy is the key to a successful therapeutic intervention, especially in cardiovascular diseases in which a lack of adherence may have serious consequences in terms morbidity and/or mortality. In this context, hair analysis can be an excellent tool to monitor adherence to therapy. Indeed, drugs present in blood are incorporated into the hair matrix, where drugs and metabolites can stay unaltered for a long time protected from metabolism and degradation. In the present study, a simple, specific, and sensitive ultra-high performance liquid-chromatography-tandem mass spectrometry (UHPLC-MS/MS) method set up to determine in human hair seven beta-blockers (viz., metoprolol, sotalol, labetalol, atenolol, nebivolol, bisoprolol, and nadolol) and two calcium-channel blockers (lercanidipine and amlodipine), which are widely prescribed to treat medium-to-severe hypertensive conditions. The optimized method was successfully validated in terms of accuracy, repeatability, reproducibility, matrix effect and extraction recovery. Moreover, the applicability of the method was evaluated by analyzing 34 real samples of hair obtained from patients under long-term therapy with calcium channel blockers and beta-blockers.

Utility of micro-CT for dating post-cranial fractures of known post-traumatic ages through 3D measurements of the trabecular inner morphology.

Fracture dating is an issue at the forefront of forensic sciences. While dating fracture is crucial to understanding and verifying the chronology of events in cases of abuse and violent death, its application is the subject of considerable discussion in the scientific community, filled with limitations and difficulties. Current methods for fracture dating are mainly based on a qualitative assessment through macroscopy, microscopy, and imaging and subject to variations depending on the experience of the observer. In this paper, we investigated the potential of quantifiable micro-CT analysis for fracture dating. Five histomorphometric parameters commonly used for the study of the 3D bone trabecular microarchitecture with micro-CT were calculated based on nine fractures of known post-traumatic ages, including the degree of anisotropy, connectivity density, bone volume fraction, trabecular thickness, and trabecular separation. As a result, trends in the evolution of the microarchitecture of the bone relative to age of the callus could be identified, in particular concerning anisotropy, trabecular separation and connectivity density, consistent with the healing bone process. The findings obtained in this pilot study encourage further research in quantifiable parameters of the bone microarchitecture as they could represent useful features for the construction of objective models for fracture dating.

Development of a new ultra-high-performance liquid chromatography-tandem mass spectrometry method for the determination of digoxin and digitoxin in plasma: Comparison with a clinical immunoassay.

Cardiac glycosides digoxin and digitoxin are used in therapy for the treatment of congestive heart failure. Moreover, these compounds can be responsible for intoxication cases caused by fortuitous ingestion of leaves of Digitalis. Due to the narrow therapeutic range of these drugs, therapeutic drug monitoring is recommended in the clinical practice. In this context, immunoassays-based methods are generally employed but digoxin- and digitoxin-like compounds can interfere with the analysis. The aim of this study was to develop and validate an original UPLC-MS/MS method for the determination of digoxin and digitoxin in plasma. The method shows adequate sensitivity and selectivity with acceptable matrix effects and very good linearity, accuracy, precision, and recovery. A simple liquid-liquid extraction procedure was used for sample clean-up. The method was applied for the analysis of n = 220 plasma samples collected in two different clinical chemistry laboratories and previously tested by the same immunoassay. The statistical comparison showed a relevant negative bias of the UPLC-MS/MS method versus the immunoassay. These results are consistent with an immunoassay overestimation of digoxin plasmatic levels due to cross-reaction events with endogenous digoxin-like substances.

CDT vs. GGT for the certification of the fitness to hold the driving license. A comparison based on the association of incremented values with the occurrence of alcohol-related road traffic accidents.

BACKGROUND: In the context of fitness certification to hold the driving license, GGT and CDT have been used, sometimes in combination (γ-CDT), to exclude chronic alcohol abuse. The present study was carried out with the aim of comparing the power of these biomarkers as tools for the objective screening of subjects at high risk of alcohol-associated traffic injuries. METHODS: 288 male drivers admitted to hospital after traffic accidents were examined by determination of GGT, CDT and BAC. The degree of association of GGT, CDT and γ-CDT with BAC was analysed using non-parametric statistics. RESULTS: Partitioning the cases using the cut-off concentrations of 0.5 g/L for BAC (the legal limit adopted in most European countries), 55 U/L for GGT and 1.9% for CDT, a highly significant difference was found between the frequency of elevated GGT or CDT in cases where BAC was within the legal limits and those with elevated BAC values (Fisher's exact test: p < 0.001). However, the calculation of the odds ratio showed a much higher increase for CDT (28 times) than for GGT (6 times) in those drivers with a BAC above the Italian legal limit in comparison with those showing a BAC within the cut-off; conversely, γ-CDT does not provide any significant advantage vs. CDT alone. CONCLUSIONS: Both GGT and CDT provide objective evidence of an association with the occurrence of alcohol-related severe traffic accidents, but CDT shows superior association with these events. Therefore, CDT, notwithstanding higher costs, should be preferred in a forensic/certification context.

The problem of dating fractures: A retrospective observational study of radiologic features of fracture healing in adults.

Accurate dating of bone fractures can be crucial in the context of forensic trauma analysis since it may provide essential information for the corroboration or contradiction of statements by victims or suspects in cases of domestic abuse or torture. The different stages of bone healing have been well described in the existing literature, and some previous studies attempted to define related timelines particularly in the paediatric population. However, the bone healing process can be very variable and despite the importance of the topic in the forensic field, so far little is known about the radiological appearance of bone fractures at different healing stages, and how this correlates with time, especially in an adult population. The aim of this retrospective observational study was to describe the temporal aspect of pre-defined healing stages as they appear on radiographs of tubular bone fractures in adults, and explore the effect of potential cofounding variables. A dynamic nomogram was developed as a user-friendly tool to be eventually applied in clinical or medico-legal settings. This study showed that the posttraumatic time interval (PTTI) increased progressively with the pre-defined healing stages. However, confounding factors, such as patients' age, sex, and location of the fracture need to be accounted for in the final estimation model. Further studies are needed to explore more potentially confounding variables to refine the presented outcomes. Better knowledge of the effect of different confounding variables in the dating of fracture healing will contribute to greater accuracy of PTTI estimation of bone fractures in adults.

A novel high-throughput liquid chromatography assay for Carbohydrate-Deficient transferrin (CDT) based on flow-modulated isocratic elution and terbium-induced fluorescence.

Transferrin is a glycoprotein containing two bi- or tri-antennary carbohydrate chains ending with sialic acid. Its glycosylation is reduced in chronic alcohol abuse and in inborn glycosylation pathologies, where the carbohydrate-deficient fraction of the protein (CDT) increases significantly. The current methods require a gradient chromatographic separation and time-consuming sample preparation. In comparison, the proposed approach uses a novel flow-modulated liquid chromatography technique (fmLC) and a highly selective and sensitive fluorescence derivatization reaction with terbium ion. A fmLC-FLD method using isocratic anion exchange separation was optimized and validated to resolve disialo-transferrin and trisialo-transferrin from other transferrin glycoforms. Detection took place by recording fluorescence at 550 nm wavelength (excitation at 298 nm). The chromatographic separation needed 5 min, allowing seriate injection every 7.5 min. The method was validated according to the current guidelines of analytical chemistry showing adequate accuracy and precision for the quantitative determination of CDT. The proposed method proved also to be suitable to analyse haemolyzed sera which, because of interference by haemoglobin, fail the standard HPLC-Vis analysis. The method was tested in parallel with HPLC-Vis on 131 sera showing an excellent correlation of results proved by a correlation coefficient of 0.995 (Pearson's r). The proposed approach proved much simpler than the current methods and cheaper in terms of instrumental costs offering a ground-breaking analytical tool that could likely make available the characterization of CDT outside specialized laboratories, such as in occupational medicine centres, doctor's offices, small laboratories, alcohol rehabilitation centres, and in developing countries.