Therapeutic potential to target sialylation and SIGLECs in neurodegenerative and psychiatric diseases.

Sialic acids, commonly found as the terminal carbohydrate on the glycocalyx of mammalian cells, are pivotal checkpoint inhibitors of the innate immune system, particularly within the central nervous system (CNS). Sialic acid-binding immunoglobulin-like lectins (SIGLECs) expressed on microglia are key players in maintaining microglial homeostasis by recognizing intact sialylation. The finely balanced sialic acid-SIGLEC system ensures the prevention of excessive and detrimental immune responses in the CNS. However, loss of sialylation and SIGLEC receptor dysfunctions contribute to several chronic CNS diseases. Genetic variants of SIGLEC3/CD33, SIGLEC11, and SIGLEC14 have been associated with neurodegenerative diseases such as Alzheimer's disease, while sialyltransferase ST8SIA2 and SIGLEC4/MAG have been linked to psychiatric diseases such as schizophrenia, bipolar disorders, and autism spectrum disorders. Consequently, immune-modulatory functions of polysialic acids and SIGLEC binding antibodies have been exploited experimentally in animal models of Alzheimer's disease and inflammation-induced CNS tissue damage, including retinal damage. While the potential of these therapeutic approaches is evident, only a few therapies to target either sialylation or SIGLEC receptors have been tested in patient clinical trials. Here, we provide an overview of the critical role played by the sialic acid-SIGLEC axis in shaping microglial activation and function within the context of neurodegeneration and synaptopathies and discuss the current landscape of therapies that target sialylation or SIGLECs.

Understanding the effect of spatial positioning of coated blade spray devices relative to the mass spectrometry inlet on different instrument platforms and its application to quantitative analysis of fentanyl and related analogs.

RATIONALE: We evaluated the effect that the spatial positioning of coated-blade spray (CBS) devices with respect to the mass spectrometry (MS) inlet has when coupling to diverse MS platforms (i.e., triple quadrupole, linear ion trap and time of flight). Furthermore, as a proof of concept, we evaluated CBS-MS as a tool for quantitation of fentanyl and four analogues on said instruments. METHODS: Custom-made MS interfaces were made to accurately position the blade in front of the MS inlet. CBS devices, coated with hydrophilic-lipophilic balanced particles, were used for both the optimization of the CBS position and the quantitation of fentanyl and analogues in urine and plasma samples on all instruments. RESULTS: The SCIEX triple quadrupole instrument was the most sensitive to the position of the blade due to the presence of a curtain gas flowing laminarly out of the MS inlet. After optimization, the analytical capabilities of CBS on each instrument were assessed and the results obtained on both SCIEX and Waters platforms matched the performance obtained using a more advanced instrument by ThermoFisher Scientific. Furthermore, excellent figures of merit were attained for the quantitation of fentanyl and analogues on both triple quadrupole and linear ion trap platforms. CONCLUSIONS: We demonstrated that optimization of MS parameters on different instrument vendors and front ends, such as the position of the CBS tip regarding the MS inlet, is vital to exploit the full quantitative potential of this technology. Application of the technology to screen and quantify fentanyl and analogues showed great potential when considering its coupling with portable mass spectrometers for therapeutic drug monitoring and point-of-care applications.

Differences in the baseline characteristics, management and outcomes of patients with hip fractures depending on their pre-fracture place of residence: the Spanish National Hip Fracture Registry (RNFC) cohort.

PURPOSE: One in four hip fracture patients comes from an aged care facility. This study aimed to compare the characteristics of these subjects with their community-dwelling counterparts at baseline, during hospitalization and 1-month post-fracture. METHODS: We analyzed data from a cohort of older adults admitted with hip fractures to 75 Spanish hospitals, collected prospectively in the Spanish National Hip Fracture Registry between 2016 and 2018. We classified participants according to pre-fracture residence: community dwellers vs. aged care facilities residents. We collected demographic records at baseline, along with variables relating to in-hospital evolution and discharge to geriatric rehabilitation units. Patients or relatives were interviewed at 1-month follow-up. RESULTS: Out of 18,262 patients, 4,422 (24.2%) lived in aged care facilities. Aged care facilities residents were older (median age: 89 vs. 86 years), less mobile (inability to walk independently: 20.8% vs. 9.4%) and had more cognitive impairment (Pfeiffer's SPMSQ > 3, 75.3% vs. 34.8%). They were more likely to receive conservative treatment (5.4% vs. 2.0%) and less likely to be mobilized early (58.2% vs. 63.0%). At discharge, they received less vitamin D supplements (68.5% vs. 72.4%), less anti-osteoporotic medication (29.3% vs. 44.3%), and were referred to geriatric rehabilitation units less frequently (5.4% vs. 27.5%). One-month post-fracture, 45% of aged care facilities residents compared to 28% of community dwellers experienced a severe gait decline. Aged care facilities residents had a higher one-month mortality (10.6% vs. 6.8%). CONCLUSION: Hip fracture patients from aged care facilities are more vulnerable than their community-dwelling peers and are managed differently both during hospitalization and at discharge. Gait decline is disproportionately higher among those admitted from aged care.

Solid phase microextraction chemical biopsy tool for monitoring of doxorubicin residue during in vivo lung chemo-perfusion.

Development of a novel in vivo lung perfusion (IVLP) procedure allows localized delivery of high-dose doxorubicin (DOX) for targeting residual micrometastatic disease in the lungs. However, DOX delivery via IVLP requires careful monitoring of drug level to ensure tissue concentrations of this agent remain in the therapeutic window. A small dimension nitinol wire coated with a sorbent of biocompatible morphology (Bio-SPME) has been clinically evaluated for in vivo lung tissue extraction and determination of DOX and its key metabolites. The in vivo Bio-SPME-IVLP experiments were performed on pig model over various (150 and 225 mg/m2) drug doses, and during human clinical trial. Two patients with metastatic osteosarcoma were treated with a single 5 and 7 µg/mL (respectively) dose of DOX during a 3-h IVLP. In both pig and human cases, DOX tissue levels presented similar trends during IVLP. Human lung tissue concentrations of drug ranged between 15 and 293 µg/g over the course of the IVLP procedure. In addition to DOX levels, Bio-SPME followed by liquid chromatography-mass spectrometry analysis generated 64 metabolic features during endogenous metabolite screening, providing information about lung status during drug administration. Real-time monitoring of DOX levels in the lungs can be performed effectively throughout the IVLP procedure by in vivo Bio-SPME chemical biopsy approach. Bio-SPME also extracted various endogenous molecules, thus providing a real-time snapshot of the physiology of the cells, which might assist in the tailoring of personalized treatment strategy.

Rapid determination of tacrolimus and sirolimus in whole human blood by direct coupling of solid-phase microextraction to mass spectrometry via microfluidic open interface.

Immunosuppressive drugs are administered to decrease immune system activity (e.g. of patients undergoing solid organ transplant). Concentrations of immunosuppressive drugs (ISDs) in circulating blood must be closely monitored during the period of immunosuppression therapy due to adverse effects that take place when concentration levels fall outside of the very narrow therapeutic concentration range of these drugs. This study presents the rapid determination of four relevant immunosuppressive drugs (tacrolimus, sirolimus, everolimus, and cyclosporine A) in whole human blood by directly coupling solid-phase microextraction to mass spectrometry via the microfluidic open interface (Bio-SPME-MOI-MS/MS). The BioSPME-MOI-MS/MS method offers ≤ 10% imprecision of in-house prepared quality controls over a 10-day period, ≤ 10% imprecision of ClinCal® Recipe calibrators over a three-day period, and single total turnaround time of ∼ 60 min (4.5 min for high throughput). The limits of quantification were determined to be 0.8 ng mL-1 for tacrolimus, 0.7 ng mL-1 sirolimus, 1.0 ng mL-1 for everolimus, and 0.8 ng mL-1 for cyclosporine. The limits of detection were determined to be 0.3 ng mL-1 for tacrolimus, 0.2 ng mL-1 for sirolimus, 0.3 ng mL-1 for everolimus, and 0.3 ng mL-1 for cyclosporine A. The R2 values for all analytes were above 0.9992 with linear dynamic range from 1.0 mL-1 to 50.0 ng mL-1 for tacrolimus, sirolimus, and everolimus while from 2.5 ng mL-1 to 500.0 ng mL-1 for cyclosporine A. To further evaluate the performance of the present method, 95 residual whole blood samples of tacrolimus and sirolimus from patients undergoing immunosuppression therapy were used to compare the Bio-SPME-MOI-MS/MS method against a clinically validated reference method based on chemiluminescent microparticle immunoassay, showing acceptable results. Our results demonstrated that Bio-SPME-MOI-MS/MS can be considered as a suitable alternative to existing methods for the determination of immunosuppressive drugs in whole blood providing faster analysis, better selectivity and sensitivity, and a wider dynamic range than current existing approaches.

Assessment of solid phase microextraction as a sample preparation tool for untargeted analysis of brain tissue using liquid chromatography-mass spectrometry.

This work presents an evaluation of solid-phase microextraction (SPME) SPME in combination with liquid chromatography-high resolution mass spectrometry (LC-HRMS) as an analytical approach for untargeted brain analysis. The study included a characterization of the metabolite coverage provided by C18, mixed-mode (MM, with benzene sulfonic acid and C18 functionalities), and hydrophilic lipophilic balanced (HLB) particles as sorbents in SPME coatings after extraction from cow brain homogenate at static conditions. The effects of desorption solvent, extraction time, and chromatographic modes on the metabolite features detected were investigated. Method precision and absolute matrix effects were also assessed. Among the main findings of this work, it was observed that all three tested coating chemistries were able to provide comparable brain tissue information. HLB provided higher responses for polar metabolites; however, as these fibers were prepared in-house, higher inter-fiber relative standard deviations were also observed. C18 and HLB coatings offered similar responses with respect to lipid-related features, whereas MM and C18 provided the best results in terms of method precision. Our results also showed that the use of methanol is essential for effective desorption of non-polar metabolites. Using a reversed-phase chromatographic method, an average of 800 and 1200 brain metabolite features detected in positive and negative modes, respectively, met inter-fibre RSD values below 30% (n=4) after removal of fibre and solvent artefacts from the associated datasets. For features detected using a lipidomics method, a total of 900 and 1800 features detected using C18 fibers in positive and negative mode, respectively, met the same criteria. In terms of absolute matrix effects, the majority of the model metabolites tested showed values between 80 and 120%, which are within the acceptable range. Overall, the findings of this work lay the foundation for further optimization of parameters for SPME-LC-HRMS methods suitable for in vivo and ex vivo brain (and other tissue) untargeted studies, and support the applicability of this approach for non-destructive tissue metabolomics.

Analysis of food samples made easy by microextraction technologies directly coupled to mass spectrometry.

Because of the complexity and diversity of food matrices, their chemical analysis often entails several analytical challenges to attain accurate and reliable results, especially for multiresidue analysis and ultratrace quantification. Nonetheless, microextraction technology, such as solid-phase microextraction (SPME), has revolutionized the concept of sample preparation for complex matrices because of its nonexhaustive, yet quantitative extraction approach and its amenability to coupling to multiple analytical platforms. In recent years, microextraction devices directly interfaced with mass spectrometry (MS) have redefined the analytical workflow by providing faster screening and quantitative methods for complex matrices. This review will discuss the latest developments in the field of food analysis by means of microextraction approaches directly coupled to MS. One key feature that differentiates SPME-MS approaches from other ambient MS techniques is the use of matrix compatible extraction phases that prevent biofouling, which could drastically affect the ionization process and are still capable of selective extraction of the targeted analytes from the food matrix. Furthermore, the review examines the most significant applications of SPME-MS for various ionization techniques such as direct analysis in real time, dielectric barrier desorption ionization, and some unique SPME geometries, for example, transmission mode SPME and coated blade spray, that facilitate the interface to MS instrumentation.

Solid phase microextraction chemical biopsy tool for monitoring of doxorubicin residue during in vivo lung chemo-perfusion / 药物分析学报

Development of a novel in vivo lung perfusion(IVLP)procedure allows localized delivery of high-dose doxorubicin(DOX)for targeting residual micrometastatic disease in the lungs.However,DOX delivery via IVLP requires careful monitoring of drug level to ensure tissue concentrations of this agent remain in the therapeutic window.A small dimension nitinol wire coated with a sorbent of biocompatible morphology(Bio-SPME)has been clinically evaluated for in vivo lung tissue extraction and determina-tion of DOX and its key metabolites.The in vivo Bio-SPME-IVLP experiments were performed on pig model over various(150 and 225 mg/m2)drug doses,and during human clinical trial.Two patients with metastatic osteosarcoma were treated with a single 5 and 7 μg/mL(respectively)dose of DOX during a 3-h IVLP.In both pig and human cases,DOX tissue levels presented similar trends during IVLP.Human lung tissue concentrations of drug ranged between 15 and 293 μg/g over the course of the IVLP procedure.In addition to DOX levels,Bio-SPME followed by liquid chromatography-mass spectrometry analysis generated 64 metabolic features during endogenous metabolite screening,providing information about lung status during drug administration.Real-time monitoring of DOX levels in the lungs can be per-formed effectively throughout the IVLP procedure by in vivo Bio-SPME chemical biopsy approach.Bio-SPME also extracted various endogenous molecules,thus providing a real-time snapshot of the physi-ology of the cells,which might assist in the tailoring of personalized treatment strategy.

Comprehensive Investigation of Metabolic Changes Occurring in the Rat Brain Hippocampus after Fluoxetine Administration Using Two Complementary In Vivo Techniques: Solid Phase Microextraction and Microdialysis.

Fluoxetine is among the most prescribed antidepressant drugs worldwide. Nevertheless, limited information is known about its definitive mechanism. Although in vivo examinations performed directly in related brain structures can provide more realistic, and therefore more insightful, knowledge regarding the mechanisms and efficacy of this drug, only a few techniques are applicable for in vivo monitoring of metabolic alterations in the brain following an inducement. Among them, solid phase microextraction (SPME) and microdialysis (MD) have emerged as ideal in vivo tools for extraction of information from biosystems. In this investigation, we scrutinized the capabilities of SPME and MD to detect ongoing changes in the brain following acute fluoxetine administration. Sequential in vivo samples were collected simultaneously from male rats' hippocampi using SPME and MD before drug administration in order to establish a baseline; then samples were collected again following fluoxetine administration for an investigation of small molecule alterations. Our results indicate that MD provides more comprehensive information for polar compounds, while SPME provides superior information with respect to lipids and other medium level polar molecules. Interestingly, in the lipidomic investigation, all dysregulated features were found to be membrane lipids and associated compounds. Moreover, in the metabolomic investigations, dysregulation of hippocampal metabolite levels associated with fatty acid transportation and purine metabolisms were among the most notable findings. Overall, our evaluation of the obtained data corroborates that, when used in tandem, SPME and MD are capable of providing comprehensive information regarding the effect of fluoxetine in targeted brain structures and further elucidating this drug's mechanisms of action in the brain.

Investigation of Early Death-Induced Changes in Rat Brain by Solid Phase Microextraction via Untargeted High Resolution Mass Spectrometry: In Vivo versus Postmortem Comparative Study.

Analysis of brain samples obtained postmortem remains a standard approach in neuroscience, despite often being suboptimal for inferring roles of small molecules in the pathophysiology of brain diseases. Sample collection and preservation further hinders conclusive interpretation of biomarker analysis in autopsy samples. We investigate purely death-induced changes affecting rat hippocampus in the first hour of postmortem interval (PMI) by means of untargeted liquid chromatography-mass spectrometry-based metabolomics. The unique possibility of sampling the same brain area of each animal both in vivo and postmortem was enabled by employing solid phase microextraction (SPME) probes. Four millimeter probes coated with mixed mode extraction phase were used to sample awake, freely roaming animals, with 2 more sampling events performed after death. Significant changes in brain neurochemistry were found to occur as soon as 30 min after death, further progressing with increasing PMI, evidenced by relative changes in levels of metabolites and lipids. These included species from several distinct groups, which can be classified as engaged in energy metabolism-related processes, signal transduction, neurotransmission, or inflammatory response. Additionally, we perform thorough analysis of interindividual variability in response to death, which provides insights into how this aspect can obscure conclusions drawn from an untargeted study at single metabolite and pathway level. The results suggest high demand for systematic studies examining the PMI time course with in vivo sampling as a starting point to eliminate artifacts in the form of neurochemical changes assumed to occur in vivo.

Unexpected Hair Regrowth in a Patient with Longstanding Alopecia Universalis During Treatment of Recalcitrant Dermatomyositis with the Janus Kinase Inhibitor Ruxolitinib.

is missing (Short communication).

Optimization of Coated Blade Spray for Rapid Screening and Quantitation of 105 Veterinary Drugs in Biological Tissue Samples.

Rapid and efficient determination of contaminants at trace levels in tissue samples has become an unmet need around the globe. Coated blade spray (CBS) extraction/ionization is a technology capable of performing, with a single device, enrichment of analytes present in complex matrices, as well as the direct interface and introduction of said analytes into the mass spectrometer via electrospray ionization. To facilitate the challenging rapid tissue screening, we describe for the first time the use of a very thin layer of biocompatible polyacrylonitrile as a CBS device undercoating to make metal surface biocompatible. This add-on is meant to protect the portion of the uncoated stainless-steel of the blade that is normally exposed to the matrix, consequently becoming susceptible to adhesion of matrix macromolecules, cells, and fat. In addition, we present for the first time the use of CBS in negative ionization mode for quantitative purposes. The optimized CBS workflow allows for rapid and high-throughput screening and quantitation of 105 veterinary drugs in homogenized bovine tissue in both negative and positive ionization mode in one single run using a single CBS device with analysis times as short as 1 min per sample when 96 extractions are simultaneously conducted. While only two internal standards were used for correction, one per ionization mode, excellent accuracy and precision were achieved, with more than 90% of analytes falling within the 70-120% range of their true concentrations and yielding RSD ≤ 25% at three validation levels. The majority of analytes achieved linear correlation coefficients >0.99, and all 105 analytes were able to meet both Canadian and U.S. regulatory levels.

Evolución clínica y funcional de los pacientes que ingresan en residencias tras una fractura de cadera. Implementación de un programa de intervención multinivel / Functional and clinical outcomes in patients admitted to nursing homes after hip fractures. Implementation of a multi-level intervention program

ANTECEDENTES Y OBJETIVO: Conocer la situación de los pacientes que ingresan en residencias de ancianos para recuperación tras una fractura de cadera y valorar su perfil de recuperación clínica y funcional. MATERIAL Y MÉTODOS: Se incluyó a los pacientes ingresados tras una fractura de cadera en los centros de un grupo residencial durante 2016. Se estandarizó un sistema de valoración y tratamiento y se les siguió durante 90 días. Se evaluó el estado nutricional (mediante el Mini-Nutritional Assessment y el índice de masa corporal), la presencia de dolor (mediante una escala analógica visual y la escala PAINAD) y la existencia de úlceras por presión, estudio analítico (vitamina D, hemoglobina y proteínas) y la situación funcional (mediante el índice de Barthel y la escala Functional Assessment Categories). RESULTADOS: En total 116 pacientes cumplieron los criterios de inclusión. La edad media fue 84,9 años (+/-6,7 DE) y 91 fueron mujeres (78,4%). Al ingreso, en las personas en las que pudo determinarse (56%), el 73,8% presentaron anemia, el 76,7% hipovitaminosis D, el 88% malnutrición o riesgo y el 15,3% úlceras por presión. Entre el ingreso y los 90 días, el estado funcional moderado-severo (IB < 60) se redujo del 90,4 al 39,6%, la dependencia para la deambulación del 97,3 al 36,1% y el dolor moderado-severo del 88,9 al 14,4% de los casos. Se resolvieron el 94,4% de las úlceras por presión. CONCLUSIONES: Los pacientes derivados a residencias tras una fractura de cadera se trasladan en mala situación clínica y funcional. A los 90 días, se obtienen buenos resultados en la recuperación funcional y de la marcha, en el control del dolor y en la cura de las úlceras por presión

BACKGROUND AND OBJECTIVE: The aim of this study was to determine the clinical and functional outcomes of patients discharged to nursing homes after a hip fracture. METHODS: The study included all patients admitted to a group of nursing homes after a hip fracture in 2016. A geriatric assessment protocol was applied, and patients were treated with a specific protocol for 90 days. They were assessed for nutritional status (Mini-Nutritional Assessment and Body Mass Index), pain (Visual Analogue Scale, and the PAINAD Scale), the presence of pressure ulcers, blood test (D vitamin, haemoglobin, proteins), and functional status (Barthel index and Functional Assessment Categories). RESULTS: Out of a total of 175 patients, 116 (75%) met the inclusion criteria. The mean age was 84.9 years old (+/-6.7 SD), and 91 (78.4%) were women. At admission, 73.8% of 65 residents had anaemia, 76.7% hypovitaminosis D, 88% malnutrition or «at risk of malnutrition», and 15.3% had pressure ulcers. After 90 days, the moderate-severe functional status (Barthel index < 60) was reduced from 90.4 to 39.6%, dependence due to gait from 97.3 to 36.1%, and moderate-severe pain from 88.9 to 14.4%. Most of the pressure ulcers healed (94.4%). CONCLUSIONS: Patients admitted to nursing homes after a hip fracture had poor clinical and functional status. This study shows that after 90 days from admission these patients had positive outcomes in terms of functionality, gait, pain control, and pressure ulcers healing

Evaluation of a coated blade spray-tandem mass spectrometry assay as a new tool for the determination of immunosuppressive drugs in whole blood.

Immunosuppressive drugs (ISDs) are primarily administered following solid organ transplant or for treatment of a variety of autoimmune conditions. Their principal function is to suppress the activity of the immune system; however, the levels must be carefully monitored due to adverse effects of over- or underadministration. A technology for rapid quantitative screening, named coated blade spray (CBS), was directly coupled to a triple quadrupole mass spectrometer (MS/MS) to measure the concentration of ISDs (i.e., cyclosporine A, tacrolimus, everolimus, sirolimus) in whole blood samples. We evaluated the stability of replicate measurements over a 10-day period (precision), assessed linearity and limit of quantification, and performed a method comparison against a validated clinical immunoassay (Abbott ARCHITECT). Total interday variation of less than 5% for all target compounds at three different concentrations was achieved. The sensitivity of the method was determined as 0.25, 1, 1, and 2.5 ng/mL for everolimus, sirolimus, tacrolimus, and cyclosporine A, respectively. The concentrations of three immunosuppressive drugs in 284 patient samples (i.e., ~ 95 samples of cyclosporine A, tacrolimus, or sirolimus) obtained using the CBS-MS/MS methodology were compared with concentrations previously quantified on an Abbott ARCHITECT immunoassay system. Our analysis demonstrated significant statistical similarities between both methods. The results demonstrate that CBS-MS/MS is a suitable alternative to conventional methodologies for monitoring of ISDs from whole blood in a clinical setting. Graphical abstract.

[Functional and clinical outcomes in patients admitted to nursing homes after hip fractures. Implementation of a multi-level intervention program]. / Evolución clínica y funcional de los pacientes que ingresan en residencias tras una fractura de cadera. Implementación de un programa de intervención multinivel.

BACKGROUND AND OBJECTIVE: The aim of this study was to determine the clinical and functional outcomes of patients discharged to nursing homes after a hip fracture. METHODS: The study included all patients admitted to a group of nursing homes after a hip fracture in 2016. A geriatric assessment protocol was applied, and patients were treated with a specific protocol for 90 days. They were assessed for nutritional status (Mini-Nutritional Assessment and Body Mass Index), pain (Visual Analogue Scale, and the PAINAD Scale), the presence of pressure ulcers, blood test (D vitamin, haemoglobin, proteins), and functional status (Barthel index and Functional Assessment Categories). RESULTS: Out of a total of 175 patients, 116 (75%) met the inclusion criteria. The mean age was 84.9 years old (±6.7 SD), and 91 (78.4%) were women. At admission, 73.8% of 65 residents had anaemia, 76.7% hypovitaminosis D, 88% malnutrition or «at risk of malnutrition¼, and 15.3% had pressure ulcers. After 90 days, the moderate-severe functional status (Barthel index < 60) was reduced from 90.4 to 39.6%, dependence due to gait from 97.3 to 36.1%, and moderate-severe pain from 88.9 to 14.4%. Most of the pressure ulcers healed (94.4%). CONCLUSIONS: Patients admitted to nursing homes after a hip fracture had poor clinical and functional status. This study shows that after 90 days from admission these patients had positive outcomes in terms of functionality, gait, pain control, and pressure ulcers healing.

In†Vivo Solid-Phase Microextraction for Sampling of Oxylipins in Brain of Awake, Moving Rats.

Oxylipins are key lipid mediators of important brain processes, including pain, sleep, oxidative stress, and inflammation. For the first time, an in-depth profile of up to 52 oxylipins can be obtained from the brains of awake moving animals using in vivo solid-phase microextraction (SPME) chemical biopsy tool in combination with liquid chromatography-high resolution mass spectrometry. Among these, 23 oxylipins are detectable in the majority of healthy wildtype samples. This new approach successfully eliminates the changes in oxylipin concentrations routinely observed during the analysis of post-mortem samples, allows time-course monitoring of their concentrations with high spatial resolution in specific brain regions of interest, and can be performed using the same experimental set-up as in vivo microdialysis (MD) thus providing a new and exciting tool in neuroscience and drug discovery.

Hepatopatía fatal por amoxicilina-clavulánico en paciente nonagenaria / Fatal liver disease due to amoxicillin-clavulanic acid in nonagenarian patient

No disponible

Analysis of endocannabinoids in plasma samples by biocompatible solid-phase microextraction devices coupled to mass spectrometry.

Anandamide (AEA) and 2-arachidonoyl glycerol (2-AG) represent two of the most important endocannabinoids (ECs) investigated in neurobiology as therapeutic targets for several mental disorders. However, the determination of these ECs in biological matrices remains a challenging task because of the low concentrations, low stability and high protein-bound (LogP ∼ 6). This work describes innovative analytical methods based on biocompatible SPME (Bio-SPME), SPME-UHPLC-MS/MS and Bio-SPME-Nano-ESI-MS/MS, to determine AEA and 2-AG in human plasma samples. The direct coupling of Bio-SPME with nano-ESI-MS/MS can be considered an alternative tool for faster analysis. Different Bio-SPME fibers based on silica and polymeric coating (i.e. C18, C30, and HLB) were evaluated. Different desorption solvents based on combinations of methanol, acetonitrile, and isopropanol were also evaluated for efficient elution with minimum carry-over. Given the high protein binding analytes and the fact that SPME extracts the free-concentration of the analytes, the plasma samples were modified with additives such as guanidine hydrochloride (Gu-HCl), trifluoroacetic acid, and acetonitrile. This study was carried out by experimental design to achieve complete protein denaturation and the release of target analytes. The maximum extraction efficiency was obtained under the following conditions: HLB coated fibers (10 mm length, 20 µm coating thickness), matrix modified (300 µL of plasma) with 50 µL of Gu-HCL 1 mol L-1, 75 µL of ACN and 75 µL of water, and desorption with methanol/isopropanol solution (50:50, v/v). Both methods were validated based on current international guidelines and can be applied for monitoring of concentrations of endocannabinoids in plasma samples. SPME-UHPLC-MS/MS method presented lower LOQ values than SPME-nanoESI-MS/MS. The additional separation (chromatographic column) favored the detectability of LC-MS/MS method. However, the SPME-nano-ESI-MS/MS decrease the total analysis time, due to significant reductions in desorption and detection times.

Breaching the 10 Second Barrier of Total Analysis Time for Complex Matrices via Automated Coated Blade Spray.

In the development of modern analytical workflows, parameters such as sample turnaround time, cost of analysis, and ease of use must be prioritized. Automation enables reductions in total analysis time, human intervention, and cost per sample. In this report, a suitable automated coated blade spray (CBS) workflow is proposed for the screening and quantitation of multiple substances (i.e., drugs of abuse and pesticides) in complex matrices. In an attempt to reduce the total sample analysis time, several parameters were investigated, including tandem mass spectrometry (MS) dwell time, CBS spray time, and extraction time. Solid-phase microextraction (SPME) method parameters are explored, such as reduction of extraction time for increased signal-to-noise. Model compounds with a moderately wide range of molecular weights (150-500 Da), polarities, and structural diversity were selected in order to monitor analytical figures of merit during method optimization. The resultant automated CBS method proved capable of analyzing the model compounds in human urine in under 10 s total analysis time with excellent accuracy (95-120%) and precision (RSD < 12%). As an application, an automated method for the screening and quantitation of more than 150 pesticides from apple juice was demonstrated on both triple quadrupole and orbitrap instruments in under 15 s total sample analysis time.