Relationship between plasma and salivary melatonin and cortisol investigated by LC-MS/MS

2017 ◽  
Vol 55 (9) ◽  
Author(s):  
Martijn van Faassen ◽  
Rainer Bischoff ◽  
Ido P. Kema
Keyword(s):  
Mass Spectrometry ◽  
Equilibrium Dialysis ◽  
Added Value ◽  
The Novel ◽  
Plasma Melatonin ◽  
Disease States ◽  
Validation Criteria ◽  
Significant Difference ◽  
Salivary Melatonin ◽  
Free Plasma

AbstractBackground:Disturbance of the circadian rhythm has been associated with disease states, such as metabolic disorders, depression and cancer. Quantification of the circadian markers such as melatonin and cortisol critically depend on reliable and reproducible analytical methods. Previously, melatonin and cortisol were primarily analyzed separately, mainly using immunoassays.Methods:Here we describe the validation and application of a high-throughput liquid chromatography in combination with mass spectrometry (LC-MS/MS) method for the combined analysis of melatonin and cortisol in plasma and saliva. The LC-MS/MS method was validated according to international validation guidelines. We used this method to analyze total plasma, free plasma (as obtained by equilibrium dialysis) and saliva melatonin and cortisol in healthy adults.Results:Validation results for plasma and saliva melatonin and cortisol were well within the international validation criteria. We observed no difference between saliva collected by passive drooling or Salivette. Moreover, we noted a significant difference in saliva vs. free plasma melatonin. We observed on average 36% (95% CI: 4%–60%) higher salivary melatonin levels in comparison to free plasma melatonin, suggestive of local production of melatonin in the salivary glands.Conclusions:The novel outcome of this study is probably due to the high precision of our LC-MS/MS assay. These outcomes illustrate the added value of accurate and sensitive mass spectrometry based methods for the quantification of neuroendocrine biomarkers.

scholarly journals Limited predictive value of illness perceptions for short-term poor recovery in musculoskeletal pain. A multi-center longitudinal study

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
E. J. de Raaij ◽  
H. Wittink ◽  
J. F. Maissan ◽  
P. Westers ◽  
R. W. J. G. Ostelo
Keyword(s):  
Prognostic Factors ◽  
Pain Intensity ◽  
Musculoskeletal Pain ◽  
Physical Functioning ◽  
Predictive Value ◽  
Illness Perceptions ◽  
Illness Perception ◽  
Added Value ◽  
Poor Recovery ◽  
Significant Difference

Abstract Background Musculoskeletal pain (MSP) is recognized worldwide as a major cause of increased years lived with disability. In addition to known generic prognostic factors, illness perceptions (IPs) may have predictive value for poor recovery in MSP. We were interested in the added predictive value of baseline IPs, over and above the known generic prognostic factors, on clinical recovery from MSP. Also, it is hypothesized there may be overlap between IPs and domains covered by the Four-Dimensional Symptom Questionnaire (4DSQ), measuring distress, depression, anxiety and somatization. The aim of this study is twofold; 1) to assess the added predictive value of IPs for poor recovery and 2) to assess differences in predictive value for poor recovery between the Brief Illness Perception Questionnaire - Dutch Language Version (Brief IPQ-DLV) and the 4DSQ. Methods An eligible sample of 251 patients with musculoskeletal pain attending outpatient physical therapy were included in a multi-center longitudinal cohort study. Pain intensity, physical functioning and Global Perceived Effect were the primary outcomes. Hierarchical logistic regression models were used to assess the added value of baseline IPs for predicting poor recovery. To investigate the performance of the models, the levels of calibration (Hosmer-Lemeshov test) and discrimination (Area under the Curve (AUC)) were assessed. Results Baseline ‘Treatment Control’ added little predictive value for poor recovery in pain intensity [Odds Ratio (OR) 0.80 (Confidence Interval (CI) 0.66–0.97), increase in AUC 2%] and global perceived effect [OR 0.78 (CI 0.65–0.93), increase in AUC 3%]. Baseline ‘Timeline’ added little predictive value for poor recovery in physical functioning [OR 1.16 (CI 1.03–1.30), increase in AUC 2%]. There was a non-significant difference between AUCs in predictive value for poor recovery between the Brief IPQ-DLV and the 4DSQ. Conclusions Based on the findings of this explorative study, assessing baseline IPs, over and above the known generic prognostic factors, does not result in a substantial improvement in the prediction of poor recovery. Also, no recommendations can be given for preferring either the 4DSQ or the Brief IPQ-DLV to assess psychological factors.

scholarly journals The Alterations in Methylene Blue/Light-Treated Frozen Plasma Proteins Revealed by Proteomics

2021 ◽  
pp. 1-8
Author(s):  
Tiange Wu ◽  
Xiaoning Wang ◽  
Kai Ren ◽  
Xiaochen Huang ◽  
Jiankai Liu
Keyword(s):  
Mass Spectrometry ◽  
Methylene Blue ◽  
Western Blot ◽  
Blue Light ◽  
Differentially Expressed ◽  
Enzyme Linked Immunosorbent Assay ◽  
Differentially Expressed Protein ◽  
Significant Difference ◽  
Modified Proteins ◽  
Frozen Plasma

Introduction: The aim of this study was to investigate the modified proteins in methylene blue/light-treated frozen plasma (MB-FP) compared with fresh frozen plasma (FFP) in order to gain a better application of MB/light-treated plasma in clinic transfusion. Methods: MB-FP and FFP were collected from Changchun central blood station, and a trichloroacetic acid/acetone precipitation method was used to remove albumin for the enrichment of lower abundance proteins. The plasma protein in MB-FP and FFP were separated using two-dimensional gel electrophoresis (2-DE) and the differentially expressed protein spots were analyzed using mass spectrometry. Finally, the differentially expressed proteins were tested using Western blot and enzyme-linked immunosorbent assay (ELISA). Results: Approximately 14 differentially expressed protein spots were detected in the MB-FP, and FFP was chosen as the control. After 2-DE comparison analysis and mass spectrometry, 8 significantly differentially expressed protein spots were identified, corresponding to 6 different proteins, including complement C1r subcomponent (C1R), inter-alpha-trypsin inhibitor heavy chain H4 (ITI-H4), keratin, type II cytoskeletal 1 (KRT1), hemopexin (HPX), fibrinogen gamma chain (FGG), and transthyretin (TTR). Western blot showed no significant difference in the expression level of KRT1 between MB-FP and FFP (p > 0.05). Both Western blot and ELISA indicated that the level of HPX was significantly higher in FFP than in MB-FP (p < 0.05). Conclusion: This comparative proteomics study revealed that some significantly modified proteins occur in MB-FP, such as C1R, ITI-H4, KRT1, HPX, FGG, and TTR. Our findings provide more theoretical data for using MB-FP in transfusion medicine. However, the relevance of the data for the transfusion of methylene blue/light-treated plasma remains unclear. The exact modification of these proteins and the effects of these modified proteins on their functions and their effects in clinical plasma infusion need to be further studied.

Computed tomography angiography and microsurgical flaps for traumatic wounds: What is the added value?

2021 ◽  
pp. 1-9
Author(s):  
Lucas Sousa Macedo ◽  
Renato Polese Rusig ◽  
Gustavo Bersani Silva ◽  
Alvaro Baik Cho ◽  
Teng Hsiang Wei ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Upper Limb ◽  
Computed Tomography Angiography ◽  
Lower Limb ◽  
High Energy ◽  
Lower Limbs ◽  
Added Value ◽  
Vascular Lesions ◽  
Limb Injuries ◽  
Significant Difference

BACKGROUND: Microsurgical flaps are widely used to treat complex traumatic wounds of upper and lower limbs. Few studies have evaluated whether the vascular changes in preoperative computed tomography angiography (CTA) influence the selection of recipient vessel and type of anastomosis and the microsurgical flaps outcomes including complications. OBJECTIVE: The aim of this study was to evaluate if preoperative CTA reduces the occurrence of major complications (revision of the anastomosis, partial or total flap failure, and amputation) of the flaps in upper and lower limb trauma, and to describe and analyze the vascular lesions of the group with CTA and its relationship with complications. METHODS: A retrospective cohort study was undertaken with all 121 consecutive patients submitted to microsurgical flaps for traumatic lower and upper limb, from 2014 to 2020. Patients were divided into two groups: patients with preoperative CTA (CTA+) and patients not submitted to CTA (CTA–). The presence of postoperative complications was assessed and, within CTA+, we also analyzed the number of patent arteries on CTA and described the arterial lesions. RESULTS: Of the 121 flaps evaluated (84 in the lower limb and 37 in the upper limb), 64 patients underwent preoperative CTA. In the CTA+ group, 56% of patients with free flaps for lower limb had complete occlusion of one artery. CTA+ patients had a higher rate of complications (p = 0.031), which may represent a selection bias as the most complex limb injuries and may have CTA indicated more frequently. The highest rate of complications was observed in chronic cases (p = 0.034). There was no statistically significant difference in complications in patients with preoperative vascular injury or the number of patent arteries. CONCLUSIONS: CTA should not be performed routinely, however, CTA may help in surgical planning, especially in complex cases of high-energy and chronic cases, since it provides information on the best recipient artery and the adequate level to perform the microanastomosis, outside the lesion area.

Comparative Study for the Assay of Plant Derived Chemicals in Pharmaceutical Formulation Using Methods Dependent on Factorized Spectra

2021 ◽  
Author(s):  
Nesma M Fahmy ◽  
Adel M Michael
Keyword(s):  
Pharmaceutical Formulations ◽  
Pharmaceutical Formulation ◽  
Ternary Mixtures ◽  
Ratio Method ◽  
The Novel ◽  
Naturally Occurring ◽  
Accuracy And Precision ◽  
Validation Parameters ◽  
Significant Difference

Abstract Background Modern built-in spectrophotometer software supporting mathematical processes provided a solution for increasing selectivity for multicomponent mixtures. Objective Simultaneous spectrophotometric determination of the three naturally occurring antioxidants—rutin(RUT), hesperidin(HES), and ascorbic acid(ASC)—in bulk forms and combined pharmaceutical formulation. Method This was achieved by factorized zero order method (FZM), factorized derivative method (FD1M), and factorized derivative ratio method (FDRM), coupled with spectrum subtraction(SS). Results Mathematical filtration techniques allowed each component to be obtained separately in either its zero, first, or derivative ratio form, allowing the resolution of spectra typical to the pure components present in Vitamin C Forte® tablets. The proposed methods were applied over a concentration range of 2–50, 2–30, and 10–100 µg/mL for RUT, HES, and ASC, respectively. Conclusions Recent methods for the analysis of binary mixtures, FZM and FD1M, were successfully applied for the analysis of ternary mixtures and compared to the novel FDRM. All were revealed to be specific and sensitive with successful application on pharmaceutical formulations. Validation parameters were evaluated in accordance with the International Conference on Harmonization guidelines. Statistical results were satisfactory, revealing no significant difference regarding accuracy and precision. Highlights Factorized methods enabled the resolution of spectra identical to those of pure drugs present in mixtures. Overlapped spectra of ternary mixtures could be resolved by spectrum subtraction coupled FDRM (SS-FDRM) or by successive application of FZM and FD1M.

scholarly journals PhenQE8, a Novel Ligand of the Human Telomeric Quadruplex

2021 ◽  
Vol 22 (2) ◽  
pp. 749
Author(s):  
Patricia B. Gratal ◽  
Julia G. Quero ◽  
Adrián Pérez-Redondo ◽  
Zoila Gándara ◽  
Lourdes Gude
Keyword(s):  
Equilibrium Dialysis ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
The Novel ◽  
X Ray Diffraction ◽  
Telomeric Dna ◽  
Healthy Human ◽  
Quadruplex Dna ◽  
Step Procedure ◽  
G Quadruplex

A novel quadruplex ligand based on 1,10-phenanthroline and incorporating two guanyl hydrazone functionalities, PhenQE8, is reported herein. Synthetic access was gained in a two-step procedure with an overall yield of 61%. X-ray diffraction studies revealed that PhenQE8 can adopt an extended conformation that may be optimal to favor recognition of quadruplex DNA. DNA interactions with polymorphic G-quadruplex telomeric structures were studied by different techniques, such as Fluorescence resonance energy transfer (FRET) DNA melting assays, circular dichroism and equilibrium dialysis. Our results reveal that the novel ligand PhenQE8 can efficiently recognize the hybrid quadruplex structures of the human telomeric DNA, with high binding affinity and quadruplex/duplex selectivity. Moreover, the compound shows significant cytotoxic activity against a selected panel of cultured tumor cells (PC-3, HeLa and MCF-7), whereas its cytotoxicity is considerably lower in healthy human cells (HFF-1 and RPWE-1).

scholarly journals Enantioenriched Positive Allosteric Modulators Display Distinct Pharmacology at the Dopamine D1 Receptor

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3799
Author(s):  
Tim J. Fyfe ◽  
Peter J. Scammells ◽  
J. Robert Lane ◽  
Ben Capuano
Keyword(s):  
Dopamine D1 Receptor ◽  
D1 Receptor ◽  
Intrinsic Activity ◽  
Optical Isomers ◽  
Allosteric Modulators ◽  
Disease States ◽  
Starting Point ◽  
Significant Difference ◽  
Optically Pure ◽  
Allosteric Properties

(1) Background: Two first-in-class racemic dopamine D1 receptor (D1R) positive allosteric modulator (PAM) chemotypes (1 and 2) were identified from a high-throughput screen. In particular, due to its selectivity for the D1R and reported lack of intrinsic activity, compound 2 shows promise as a starting point toward the development of small molecule allosteric modulators to ameliorate the cognitive deficits associated with some neuropsychiatric disease states; (2) Methods: Herein, we describe the enantioenrichment of optical isomers of 2 using chiral auxiliaries derived from (R)- and (S)-3-hydroxy-4,4-dimethyldihydrofuran-2(3H)-one (d- and l-pantolactone, respectively); (3) Results: We confirm both the racemate and enantiomers of 2 are active and selective for the D1R, but that the respective stereoisomers show a significant difference in their affinity and magnitude of positive allosteric cooperativity with dopamine; (4) Conclusions: These data warrant further investigation of asymmetric syntheses of optically pure analogues of 2 for the development of D1R PAMs with superior allosteric properties.

scholarly journals Metabolomics in nutrition research–a powerful window into nutritional metabolism

2016 ◽  
Vol 60 (5) ◽  
pp. 451-458 ◽  
Author(s):  
Lorraine Brennan
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Data Acquisition ◽  
Small Molecules ◽  
Biological Samples ◽  
Metabolic Pathways ◽  
Recent Trend ◽  
Disease States ◽  
Nutrition Research

Metabolomics is the study of small molecules present in biological samples. In recent years it has become evident that such small molecules, called metabolites, play a key role in the development of disease states. Furthermore, metabolomic applications can reveal information about alterations in certain metabolic pathways under different conditions. Data acquisition in metabolomics is usually performed using nuclear magnetic resonance (NMR)-based approaches or mass spectrometry (MS)-based approaches with a more recent trend including the application of multiple platforms in order to maximise the coverage in terms of metabolites measured. The application of metabolomics is rapidly increasing and the present review will highlight applications in nutrition research.

scholarly journals Measurement of Midregional Proadrenomedullin in Plasma with an Immunoluminometric Assay

2005 ◽  
Vol 51 (10) ◽  
pp. 1823-1829 ◽  
Author(s):  
Nils G Morgenthaler ◽  
Joachim Struck ◽  
Christine Alonso ◽  
Andreas Bergmann
Keyword(s):  
Cardiovascular Disease ◽  
Room Temperature ◽  
Polyclonal Antibodies ◽  
Reference Interval ◽  
Healthy Individuals ◽  
Disease States ◽  
Significant Difference ◽  
Edta Plasma ◽  
Technical Evaluation ◽  
Reliable Quantification

Abstract Background: Adrenomedullin (ADM) is a potent vasodilatory peptide, and circulating concentrations have been described for several disease states, including dysfunction of the cardiovascular system and sepsis. Reliable quantification has been hampered by the short half-life, the existence of a binding protein, and physical properties. Here we report the technical evaluation of an assay for midregional pro-ADM (MR-proADM) that does not have these problems. Methods: MR-proADM was measured in a sandwich immunoluminometric assay using 2 polyclonal antibodies to amino acids 45–92 of proADM. The reference interval was defined in EDTA plasma of 264 healthy individuals (117 male, 147 female), and increased MR-proADM concentrations were found in 95 patients with sepsis and 54 patients with cardiovascular disease. Results: The assay has an analytical detection limit of 0.08 nmol/L, and the interassay CV was &lt;20% for values &gt;0.12 nmol/L. The assay was linear on dilution with undisturbed recovery of the analyte. EDTA-, heparin-, and citrate-plasma samples were stable (&lt;20% loss of analyte) for at least 3 days at room temperature, 14 days at 4 °C, and 1 year at −20 °C. MR-proADM values followed a gaussian distribution in healthy individuals with a mean (SD) of 0.33 (0.07) nmol/L (range, 0.10–0.64 nmol/L), without significant difference between males or females. The correlation coefficient for MR-proADM vs age was 0.50 (P &lt;0.001). MR-proADM was significantly (P &lt;0.001) increased in patients with cardiovascular disease [median (range), 0.56 (0.08–3.9) nmol/L] and patients with sepsis [3.7 (0.72–25.4) nmol/L]. Conclusions: MR-proADM is stable in plasma of healthy individuals and patients. MR-proADM measurements may be useful for evaluating patients with sepsis, systemic inflammation, or heart failure.

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