14 research outputs found
La restauration d’une œuvre monumentale de Lucien Simon
This short account details the issues raised during the conservation of a monumental painting intended for a theme museum with inadequate exposition space
Development and Validation of an HPLC-FLD Method for the Determination of NDMA and NDEA Nitrosamines in Lisinopril Using Pre-Column Denitrosation and Derivatization Procedure
In order to meet the analytical requirements of the European Medicines Agency (EMA), a new HPLC-FLD method was successfully developed using dansyl chloride for the derivatization and determination of the genotoxic impurities N-Nitrosodimethylamine (NDMA) and N-Nitrosodiethylamine (NDEA) in Lisinopril API and its final product. Samples’ pretreatment includes liquid–liquid microextraction, denitrosation, and derivatization steps. To optimize the process, the parameters contributing to high sensitivity and yielding reliable results were thoroughly studied and optimized using one-factor-at-a-time and experimental design approaches. The analytes were pre-column derivatized with Dansyl-Cl and analyzed by HPLC-fluorescence (λem/λem = 340/530) using a C18 column and a mixture of phosphate buffer (pH = 2.8; 20 mM)/acetonitrile 55:45 v/v as the mobile phase. The six-level concentration calibration was shown to be linear, with R equal to 0.9995 for both analytes. The limit of detection (LOD) was satisfactory and equal to 4.7 and 0.04 ng/mL for NDMA and NDEA, respectively. Precision was less than 13.4% in all cases, and the average recoveries were equal to 109.2 and 98.1% for NDMA and NDEA, respectively. The proposed procedure is relatively easy, rapid, and suitable for the determination of the two nitrosamines in routine analysis tests
Development and Validation of an HPLC-FLD Method for the Determination of NDMA and NDEA Nitrosamines in Lisinopril Using Pre-Column Denitrosation and Derivatization Procedure
In order to meet the analytical requirements of the European Medicines Agency (EMA), a new HPLC-FLD method was successfully developed using dansyl chloride for the derivatization and determination of the genotoxic impurities N-Nitrosodimethylamine (NDMA) and N-Nitrosodiethylamine (NDEA) in Lisinopril API and its final product. Samples’ pretreatment includes liquid–liquid microextraction, denitrosation, and derivatization steps. To optimize the process, the parameters contributing to high sensitivity and yielding reliable results were thoroughly studied and optimized using one-factor-at-a-time and experimental design approaches. The analytes were pre-column derivatized with Dansyl-Cl and analyzed by HPLC-fluorescence (λem/λem = 340/530) using a C18 column and a mixture of phosphate buffer (pH = 2.8; 20 mM)/acetonitrile 55:45 v/v as the mobile phase. The six-level concentration calibration was shown to be linear, with R equal to 0.9995 for both analytes. The limit of detection (LOD) was satisfactory and equal to 4.7 and 0.04 ng/mL for NDMA and NDEA, respectively. Precision was less than 13.4% in all cases, and the average recoveries were equal to 109.2 and 98.1% for NDMA and NDEA, respectively. The proposed procedure is relatively easy, rapid, and suitable for the determination of the two nitrosamines in routine analysis tests
Association of Plasma Irisin Levels with Circulating Endothelial Microparticles (EMPs) and Endothelial Progenitor Cells (EPCs) in Children Born Prematurely
Prematurity has been linked with endothelial dysfunction in later life. The purpose of this study was to evaluate the association between plasma irisin, an adipomyokine reported to protect the functional integrity of vascular endothelium, and circulating endothelial microparticles (EMPs) and endothelial progenitor cells (EPCs), consisting early biomarkers of endothelial dysfunction, in preterm-born children. We studied 131 prepubertal children; 61 preterm and 70 born at term (controls). Plasma irisin was determined by ELISA. Circulating CD62E(+), CD144(+) and CD31(+)/CD42b(-) EMPs, and CD34(+)/VEGFR-2(+)/CD45(-) and CD34(+)/VEGFR-2(+)/CD45dim EPCs, were determined by flow cytometry. Body mass index, waist-to-hip ratio, neck circumference, systolic and diastolic blood pressure, and biochemical parameters (glucose, lipids, insulin, HOMA-IR) were also evaluated. Plasma irisin was significantly lower (p = 0.001), whereas circulating EMPs and EPCs were higher, in children born prematurely compared to controls. Irisin was recognized as independent predictor for CD144(+) and CD31(+)/CD42b(-) EMPs, CD34(+)/VEGFR-2(+)/CD45(-) and CD34(+)/VEGFR-2(+)/CD45dim EPCs in the total study population, and for CD31(+)/CD42b(-) EMPs in the preterm group. In conclusion, plasma irisin correlates independently with circulating EMP and EPC subpopulations in prepubertal children and in preterm-born ones. Further studies in children will potentially elucidate the link between irisin and the primary stages of prematurity-related endothelial dysfunction
Increased circulating endothelial progenitor cells (EPCs) in prepubertal children born prematurely: a possible link between prematurity and cardiovascular risk
BackgroundEndothelial progenitor cells (EPCs) ensure vascular integrity
and neovascularization. No studies have investigated EPCs in
preterm-born children beyond infancy.MethodsOne hundred and thirty-six
prepubertal children were enrolled: 63 preterm and 73 born at term
(controls). Circulating CD34(+)/VEGFR-2(+)/CD45(-) and
CD34(+)/VEGFR-2(+)/CD45dim EPCs were measured in preterm-born children
compared to controls. Body mass index (BMI), waist-to-hip ratio (WHR),
neck circumference, systolic and diastolic blood pressure (SBP and DBP,
respectively), fasting glucose, insulin, lipid profile, common carotid
and abdominal aortic intima-media thickness (cIMT and aIMT,
respectively), endothelium-dependent brachial artery flow-mediated
dilation (FMD), and echocardiographic parameters were also
assessed.ResultsCirculating CD34(+)/VEGFR-2(+)/CD45(-) and
CD34(+)/VEGFR-2(+)/CD45dim EPCs were significantly higher in
preterm-born children compared to controls (p<0.001 and p<0.001,
respectively). In total study population and in the preterm-born group,
EPCs were significantly lower in children born to mothers with
gestational diabetes compared to non-diabetic mothers. Prematurity was
associated with higher WHR, neck circumference, SBP, DBP, cIMT, aIMT,
mean pressure, and velocity of pulmonary artery; the peak velocity of
the brachial artery was significantly lower in children born
prematurely. In multiple regression analysis, preterm birth and maternal
gestational diabetes were recognized as independent predictors of
EPCs.ConclusionsCirculating EPCs were increased in prepubertal
preterm-born children in comparison with peers born full-term. Maternal
gestational diabetes was associated with a decrease in
EPCs.ImpactMounting evidence supports the adverse effect of prematurity
on cardiovascular health. However, the underlying mechanisms that could
lead to endothelial dysfunction in preterm-born individuals are not
fully understood.Endothelial progenitor cells (EPCs) ensure vascular
integrity, normal endothelial function and neovascularization.No studies
have investigated the EPCs counts in peripheral blood beyond infancy in
children born prematurely.Circulating EPCs were significantly higher in
preterm-born prepubertal children compared to controls, thus indicating
that prematurity is possibly associated with endothelial damage.In total
study population and in the preterm-born group, maternal gestational
diabetes was associated with decreased EPCs concentrations
Elevated circulating endothelial microparticles (EMPs) in prepubertal children born preterm
Background Endothelial microparticles (EMPs) act as early biomarkers of
endothelial activation and damage. No studies have investigated EMPs in
preterm-born individuals. Methods Sixty-three preterm-born children and
52 children born full-term (controls) were studied. Circulating
CD62E(+), CD144(+), and CD31(+)/CD42b(-) EMPs were measured in
preterm-born children compared to controls; possible associations with
cardiovascular risk factors and endothelial function parameters were
also assessed. Results Circulating CD62E(+), CD144(+), and
CD31(+)/CD42b(-) EMPs were significantly higher in preterm-born children
compared to controls (p = 0.003, p < 0.001, and p < 0.001,
respectively). Preterm birth was recognized as an independent predictor
of each EMP subpopulation studied; moreover, the mean pressure and
velocity of pulmonary artery were independently correlated with CD62E(+)
(beta = 0.20, p = 0.04) and CD144(+) EMPs (beta = 0.22, p = 0.02),
respectively, whereas age (beta = 0.21, p = 0.03) and being born SGA
(beta = 0.26, p = 0.01) correlated independently with CD31(+)/CD42b(-)
EMPs in the study population. Furthermore, diastolic blood pressure
(beta = 0.24, p = 0.04), being born SGA (beta = 0.24, p = 0.04) and the
hyperemic peak velocity of the brachial artery (beta = -0.65, p = 0.02)
were independently associated with CD31(+)/CD42b(-) EMPs in the
preterm-born group. Conclusion Circulating EMPs were higher in
preterm-born children compared to children born full-term. Whether EMPs
could act, in clinical practice, as a complementary tool for
non-invasive evaluation of endothelium in preterm-born children, remains
under investigation. Impact Circulating endothelial microparticles
(EMPs) are small membrane vesicles released from endothelial cells and
they act as novel biomarkers of endothelial activation and damage. No
studies have investigated circulating EMPs in preterm-born individuals.
Circulating EMPs were significantly higher in prepubertal preterm-born
children compared to children born at term. In the preterm-born group,
the hyperemic peak velocity of the brachial artery was independently
associated with CD31(+)/CD42b(-) EMPs. Whether assessment of circulating
EMPs could act, in clinical practice, as a complementary tool for
non-invasive evaluation of endothelium in preterm-born children, remains
to be defined in future investigations
mRNA Therapeutic Modalities Design, Formulation and Manufacturing under Pharma 4.0 Principles
In the quest for a formidable weapon against the SARS-CoV-2 pandemic, mRNA therapeutics have stolen the spotlight. mRNA vaccines are a prime example of the benefits of mRNA approaches towards a broad array of clinical entities and druggable targets. Amongst these benefits is the rapid cycle “from design to production” of an mRNA product compared to their peptide counterparts, the mutability of the production line should another target be chosen, the side-stepping of safety issues posed by DNA therapeutics being permanently integrated into the transfected cell’s genome and the controlled precision over the translated peptides. Furthermore, mRNA applications are versatile: apart from vaccines it can be used as a replacement therapy, even to create chimeric antigen receptor T-cells or reprogram somatic cells. Still, the sudden global demand for mRNA has highlighted the shortcomings in its industrial production as well as its formulation, efficacy and applicability. Continuous, smart mRNA manufacturing 4.0 technologies have been recently proposed to address such challenges. In this work, we examine the lab and upscaled production of mRNA therapeutics, the mRNA modifications proposed that increase its efficacy and lower its immunogenicity, the vectors available for delivery and the stability considerations concerning long-term storage
Response Surface and Freezing-Out Methodologies for the Extraction, Separation, and Validation of Seven Vitamins in a Novel Supplement with Determination by High-Performance Liquid Chromatography
A new multivitamin supplement containing fat (A and D3) and water soluble (C, B2, B3, B6 and B12) vitamins together with nutrients for young athletes was formulated and analyzed. Due to the complexity of the matrix (excipients: Aegina peanut butter, pomegranate juice, royal jelly and chocolate), a purification process was developed using a freezing and liquid extraction technique and optimized with central composite design (CCD) methodology. For the analysis of the samples, an efficient liquid chromatography (LC) gradient elution method was developed and validated, focusing on the stability of sensitive vitamins. After investigation, a diode array detector was chosen instead of electrospray ionization mass spectrometry (ESI-Q/MS) to determine the analytes. The most suitable chromatographic conditions were selected based on a D-optimal process where a mixture component (acetonitrile and phosphate buffer 20 mM) was cross-correlated with three factors: pH, flow rate, and column temperature. The analysis was performed on a cyano column (250 × 4.6 mm, 5 µm) and validated (recovery from 98.7 to 100.4; relative standard deviation −1; limits of quantitation from 0.06 to 0.30 µg mL−1) according to International Conference on Harmonization (ICH) guidelines. The robustness was characterized based upon a Box-Behnken design process. Stability experiments indicated that the vitamins were stable for at least 1 year (recovery >97.1%).</p