Clustered de novo start-loss variants in GLUL result in a developmental and epileptic encephalopathy via stabilization of glutamine synthetase.

Glutamine synthetase (GS), encoded by GLUL, catalyzes the conversion of glutamate to glutamine. GS is pivotal for the generation of the neurotransmitters glutamate and gamma-aminobutyric acid and is the primary mechanism of ammonia detoxification in the brain. GS levels are regulated post-translationally by an N-terminal degron that enables the ubiquitin-mediated degradation of GS in a glutamine-induced manner. GS deficiency in humans is known to lead to neurological defects and death in infancy, yet how dysregulation of the degron-mediated control of GS levels might affect neurodevelopment is unknown. We ascertained nine individuals with severe developmental delay, seizures, and white matter abnormalities but normal plasma and cerebrospinal fluid biochemistry with de novo variants in GLUL. Seven out of nine were start-loss variants and two out of nine disrupted 5' UTR splicing resulting in splice exclusion of the initiation codon. Using transfection-based expression systems and mass spectrometry, these variants were shown to lead to translation initiation of GS from methionine 18, downstream of the N-terminal degron motif, resulting in a protein that is stable and enzymatically competent but insensitive to negative feedback by glutamine. Analysis of human single-cell transcriptomes demonstrated that GLUL is widely expressed in neuro- and glial-progenitor cells and mature astrocytes but not in post-mitotic neurons. One individual with a start-loss GLUL variant demonstrated periventricular nodular heterotopia, a neuronal migration disorder, yet overexpression of stabilized GS in mice using in utero electroporation demonstrated no migratory deficits. These findings underline the importance of tight regulation of glutamine metabolism during neurodevelopment in humans.

Selection of Novel Reference Genes by RNA-Seq and Their Evaluation for Normalising Real-Time qPCR Expression Data of Anthocyanin-Related Genes in Lettuce and Wild Relatives.

Lettuce is a popular vegetable source of bioactive compounds, like anthocyanins, powerful antioxidants present in red and semi-red varieties. Selection of reliable reference genes (RGs) for the normalization of real-time quantitative PCR (qPCR) data is crucial to obtain accurate gene expression results. Among the genes with totally unrelated biological functions, six candidate RGs (ADF2, CYB5, iPGAM, SCL13, TRXL3-3, and VHA-H) with low variation in expression according to RNA-seq analyses, were selected for future expression studies of anthocyanin-related genes in three different experiments: leaf colour comparison (green vs. red) in commercial varieties; tissue comparison (leaf vs. stem) in a wild relative; and drought stress experiment in commercial and traditional varieties, and a wild relative. Expression profiles of the candidate RGs were obtained by qPCR and their stability was assessed by four different analytical tools, geNorm, NormFinder, BestKeeper, and Delta Ct method, all integrated in RefFinder. All results considered, we recommend CYB5 to be used as RG for the leaf colour experiment and TRXL3-3 for the tissue and drought stress ones, as they were the most stable genes in each case. RNA-seq is useful to preselect novel RGs although validation by qPCR is still advisable. These results provide helpful information for gene expression studies in Lactuca spp. under the described conditions.

Anti-myeloperoxidase and proteinase 3 antibodies for nephritis flare prediction in anti-neutrophil cytoplasmic antibody-associated vasculitis.

BACKGROUND: The value of myeloperoxidase (MPO) and proteinase 3 (PR3) antibody titres in the assessment of renal disease activity and flare prediction in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is not well known. METHODS: We performed a retrospective study including 113 AVV patients with renal biopsy-proven pauci-immune necrotizing glomerulonephritis from seven Spanish hospitals. The main inclusion criteria were assessment of MPO antibodies using multiplex flow immunoassay and PR3 antibody measurements using immunoassay chemiluminescence with an identical range of values for all participating centres. RESULTS: Serum MPO antibodies 3 ± 1.2 months before relapse were higher in patients who relapsed [19.2 ± 12.2 versus 3.2 ± 5.1 antibody index (AI); P < 0.001]. The discrimination value of MPO antibodies 3 months before renal relapse had an area under the receiver operating characteristics curve (AUC) of 0.82 [95% confidence interval (CI) 0.73-0.92; P < 0.001]. ΔMPO antibodies (change in antibodies titration 6 months before relapse) were higher in patients who relapsed (8.3 ± 12 versus 0.9 ± 3.1 AI; P = 0.001). The discrimination value of ΔMPO had an AUC of 0.76 (95% CI 0.63-0.88; P < 0.001). The positive predictive value of renal relapse in PR3 patients is 100% and the negative predictive value of renal relapse in patients with PR3-positive titres is 57.1%. Serum PR3 antibodies were higher in patients who relapsed 2.8 ± 1.4 months before relapse (58.6 ± 24.6 versus 2.0 ± 0.6 AI; P < 0.001). CONCLUSIONS: MPO level monitoring using multiplex flow immunoassay and PR3 measurements using immunoassay chemiluminescence are useful and sensitive tools for the prediction of renal relapse in the follow-up of AAV patients with renal disease and relevant surrogate markers of renal disease activity.

Carglumic acid in methylmalonic acidemia: Use of breast milk as an alternative vehicle to water.

WHAT IS KNOWN AND OBJECTIVE: Carbaglu® or N-carbamylglutamate (NCG) is not recommended for administration in a vehicle other than water. We aim to report the use of breast milk (BM) as an alternative vehicle in a neonate rejecting NCG diluted in water. CASE SUMMARY: A neonate diagnosed with methylmalonic acidemia presented symptomatology of acidemia and hyperammonemia. After the patient refused oral NCG administration, a dissolution test was conducted in BM showing correct dissolution. The NCG-BM solution was tolerated and plasma ammonium concentrations remained within range in subsequent analytical controls. WHAT IS NEW AND CONCLUSION: BM as a vehicle for NCG is a safe and effective option for patients who refuse suspension in water and could lead to better treatment compliance in paediatric patients.

Applications of Genomic Tools in Plant Breeding: Crop Biofortification.

Crop breeding has mainly been focused on increasing productivity, either directly or by decreasing the losses caused by biotic and abiotic stresses (that is, incorporating resistance to diseases and enhancing tolerance to adverse conditions, respectively). Quite the opposite, little attention has been paid to improve the nutritional value of crops. It has not been until recently that crop biofortification has become an objective within breeding programs, through either conventional methods or genetic engineering. There are many steps along this long path, from the initial evaluation of germplasm for the content of nutrients and health-promoting compounds to the development of biofortified varieties, with the available and future genomic tools assisting scientists and breeders in reaching their objectives as well as speeding up the process. This review offers a compendium of the genomic technologies used to explore and create biodiversity, to associate the traits of interest to the genome, and to transfer the genomic regions responsible for the desirable characteristics into potential new varieties. Finally, a glimpse of future perspectives and challenges in this emerging area is offered by taking the present scenario and the slow progress of the regulatory framework as the starting point.

Safety of tocilizumab in COVID-19 pregnant women and their newborn: A retrospective study.

WHAT IS KNOWN AND OBJECTIVE: Tocilizumab is an IL-6 receptor inhibitor agent which has been proposed as a candidate to stop the inflammatory phase of infection by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). However, safety data of tocilizumab in pregnant women and their newborn are scarce. We aimed to describe maternal and neonatal safety outcomes associated with tocilizumab treatment in pregnant women with severe COVID-19. METHODS: This is a retrospective study of severe COVID-19 pregnant women, treated with tocilizumab in two Spanish hospitals between 1 March and 31 April 2020. Demographics, medical history, clinical and radiologic findings, treatment information and laboratory data of mothers and their newborns were collected from electronic medical records. RESULTS AND DISCUSSION: A total of 12 pregnant women were identified to have received tocilizumab during pregnancy in the two hospitals. Median gestational age at admission was 27.7 weeks (interquartile range, 18.0-36.4). Most of them received lopinavir/ritonavir, azithromycin and hydroxychloroquine, two patients received corticosteroids and one received interferon beta 1B. All 12 pregnancies resulted in live births. Somatometric values were normal for all newborns, and evolution at 14 and 28 days was favourable for all of them. Hepatotoxicity was observed in 2 patients, which improved or resolved at discharge. Cytomegalovirus reactivation was detected in another patient who had also received corticosteroids for 15 days, causing a congenital infection in her newborn. Both hepatotoxicity and viral reactivation adverse events were classified as possibly related to tocilizumab administration according to Naranjo's causality algorithm. WHAT IS NEW AND CONCLUSIONS: It does not appear that tocilizumab has detrimental effects for the mother and newborn. Close monitoring of infections should be considered, especially if other immunosuppressive agents are used.

Impact of drought stress on vitamin C and anthocyanin content in cultivated lettuces (Lactuca sativa L.) and wild relatives (Lactuca spp.).

Introduction: Lettuce production and quality could be seriously affected by the increasingly limited water resources. Methods: The effect of drought on the content of two antioxidant compounds, vitamin C and anthocyanins, in five cultivated lettuces and two wild relatives was assessed for 2 years. Results and discusion: In leaf samples, Lactuca wild species generally had a higher content of total vitamin C than the cultivated lettuces. In contrast, the commercial varieties usually contained more total anthocyanins than the wild species. Total vitamin C decreased with the drought stress in all accessions, commercial varieties, and lettuce wild relatives, with this tendency being consistent and reproducible across the 2 years. These differences were significant in the case of the green commercial varieties 'Winter Crop' (in 2020/2021) and 'Dolomiti G12' (in 2021/2022) and very significant in the red commercial variety 'Red Sails' (in 2020/2021). However, the only group in which the effect of drought was either significant or very significant in both years was the wild species, Lactuca homblei and Lactuca dregeana, and in the latter also in both tissues (leaf and stem) analyzed. Water stress resulted in an increase of the total anthocyanin content in the leaves from all the accessions, both red commercial varieties and wild relatives, in both years. The most significant enrichment and the only one being either significant or very significant in both years was observed in one of the wild relatives assayed (L. homblei). Stems (L. dregeana) contained more anthocyanins than leaves under control conditions, and it was exactly the opposite under drought. Changes in anthocyanins in the two tissues in response to drought stress were in opposite directions, increasing in leaves and decreasing in stems. This could suggest a translocation of anthocyanins as a first quick mechanism to cope with a severe lack of water. In conclusion, anthocyanins (unlike vitamin C) could play a role in the mechanisms deployed by the plant to tolerate drought stress. The wild species with a robust significant enrichment in anthocyanins as a response to drought (L. homblei) is a promising plant material to breed more resilient lettuces.

Dynamic changes in mitochondrial localization in human neocortical basal radial glial cells during cell cycle.

Mitochondria play critical roles in neural stem/progenitor cell proliferation and fate decisions. The subcellular localization of mitochondria in neural stem/progenitor cells during mitosis potentially influences the distribution of mitochondria to the daughter cells and thus their fates. Therefore, understanding the spatial dynamics of mitochondria provides important knowledge about brain development. In this study, we analyzed the subcellular localization of mitochondria in the fetal human neocortex with a particular focus on the basal radial glial cells (bRGCs), a neural stem/progenitor cell subtype attributed to the evolutionary expansion of the human neocortex. During interphase, bRGCs exhibit a polarized localization of mitochondria that is localized at the base of the process or the proximal part of the process. Thereafter, mitochondria in bRGCs at metaphase show unpolarized distribution in which the mitochondria are randomly localized in the cytoplasm. During anaphase and telophase, mitochondria are still localized evenly, but mainly in the periphery of the cytoplasm. Mitochondria start to accumulate at the cleavage furrow during cytokinesis. These results suggest that the mitochondrial localization in bRGCs is tightly regulated during the cell cycle, which may ensure the proper distribution of mitochondria to the daughter cells and, thus in turn, influence their fates.

Drug Cost Avoidance Resulting from Participation in Clinical Trials: A 10-Year Retrospective Analysis of Cancer Patients with Solid Tumors.

The objective of this single-center retrospective study was to describe the clinical characteristics of adult patients with solid tumors enrolled in cancer clinical trials over a 10-year period (2010-2019) and to assess drug cost avoidance (DCA) associated with sponsors' contributions. The sponsors' contribution to pharmaceutical expenditure was calculated according to the actual price (for each year) of pharmaceutical specialties that the Vall d'Hebron University Hospital (HUVH) would have had to bear in the absence of sponsorship. A total of 2930 clinical trials were conducted with 10,488 participants. There were 140 trials in 2010 and 459 in 2019 (228% increase). Clinical trials of high complexity phase I and basket trials accounted for 34.3% of all trials. There has been a large variation in the pattern of clinical research over the study period, whereas, in 2010, targeted therapy accounted for 79.4% of expenditure and cytotoxic drugs for 20.6%; in 2019, immunotherapy accounted for 68.4%, targeted therapy for 24.4%, and cytotoxic drugs for only 7.1%. A total of four hundred twenty-one different antineoplastic agents were used, the variability of which increased from forty-seven agents in 2010, with only seven of them accounting for 92.8% of the overall pharmaceutical expenditure) to three hundred seventeen different antineoplastic agents in 2019, with thirty-three of them accounting for 90.6% of the overall expenditure. The overall expenditure on antineoplastic drugs in clinical care patients not included in clinical trials was EUR 120,396,096. The total cost of antineoplastic drugs supplied by sponsors in a clinical trial setting was EUR 107,306,084, with a potential DCA of EUR 92,662,609. Overall, clinical trials provide not only the best context for the progress of clinical research and healthcare but also create opportunities for reducing cancer care costs.

Inhaled aztreonam lysine in the management of Pseudomonas aeruginosa in patients with cystic fibrosis: real-life effectiveness.

BACKGROUND: Inhaled antibiotics have achieved or stabilised the clinical condition of patients with cystic fibrosis (CF) and chronic Pseudomonas aeruginosa infection. We aimed to determine the effectiveness of aztreonam lysine inhaled solution (AZLI) in patients with CF and chronic P. aeruginosa infection. METHODS: A retrospective observational study was conducted on patients with CF and chronic P. aeruginosa infection who received AZLI between July 2012 and September 2018 inclusive in three Spanish hospitals in a routine clinical practice setting. The primary endpoint was the absolute change in the percentage of predicted forced expiratory volume in 1 second (FEV1) compared with the previous 12 months, at the start of AZLI treatment and 12 months after starting the drug. Other variables analysed were exacerbations, hospitalisations, type and route of antibiotics prescribed, weight and body mass index (BMI) and adverse drug reactions. RESULTS: In a cohort of 52 patients, AZLI treatment led to stabilisation of FEV1, changing from a mean (SD) value of 55.60 (21.3)% at the start of treatment to 56.8 (20.4)% after 12 months of treatment (p=0.5296) in patients who had not previously received the drug. In addition, it significantly reduced exacerbations from a median (P25; P75) of 2.0 (1.0; 3.0) in the 12 months prior to AZLI to 1.0 (1.0; 2.0) in the 12 months after treatment initiation (p=0.0350). AZLI also reduced the need for other antibiotics and prevented a decrease in BMI, with an adequate safety profile. CONCLUSIONS: AZLI achieved stabilisation of lung function measured by FEV1 in patients with CF and chronic P. aeruginosa infection, along with an adequate safety profile.

Medication reconciliation on admission in paediatric chronic patients: A multicentre study.

INTRODUCTION: Medication reconciliation (MC) is one of the main strategies to reduce medication errors in care transitions. In Spain, several guidelines have been published with recommendations for the implementation and development of MC aimed at the adult population, although paediatric patients are not included. In 2018, a study was carried out that led to the subsequent publication of a document with criteria for selecting paediatric patients in whom CM should be prioritised. OBJECTIVES: To describe the characteristics of paediatric patients most likely to suffer from errors of reconciliation (EC), to confirm whether the results of a previous study can be extrapolated. METHODOLOGY: Prospective, multicentre study of paediatric inpatients. We analysed the CE detected during the performance of the CM on admission. The best possible pharmacotherapeutic history of the patient was obtained using different sources of information and confirmed by an interview with the patient/caregiver. RESULTS: 1043 discrepancies were detected, 544 were identified as CD, affecting 317 patients (43%). Omission of a drug was the most common error (51%). The majority of CD were associated with drugs in groups A (31%), N (23%) and R (11%) of the ATC classification. Polymedication and onco-haematological based disease were the risk factors associated with the presence of CD with statistical significance. CONCLUSIONS: The findings of this study allow prioritisation of CM in a specific group of paediatric patients, favouring the efficiency of the process. Onco-haematological patients and polymedication are confirmed as the main risk factors for the appearance of CD in the paediatric population.

Comprehensive physicochemical characterization of a peptide-based medicine: Teduglutide (Revestive®) structural description and stress testing.

Teduglutide (Revestive®) is a glucagon-like peptide-2 analogue used for the treatment of short bowel syndrome, a rare life-threatening condition in which the amount of functional gut is too short to enable proper absorption of nutrients and fluids. During handling prior to administration to the patient in hospital, it is possible that peptide-based medicines may be exposed to environmental stress conditions that could affect their quality. It is therefore essential to carry out stress testing studies to evaluate how such medicines respond to these stresses. For this reason, in this paper we present a strategy for a comprehensive analytical characterization of a peptide and a stress testing study in which it was subjected to various stress conditions: heating at 40 °C and 60 °C, light exposure and shaking. Several complementary analytical techniques were used throughout this study: Far UV circular dichroism, intrinsic protein fluorescence spectroscopy, dynamic light scattering, size-exclusion chromatography and intact and peptide mapping reverse-phase chromatography coupled to mass spectrometry. To the best of our knowledge, this is the first study to offer an in-depth description of the chemical structure of teduglutide peptide and its physicochemical characteristics after stress stimuli were applied to the reconstituted medicine Revestive®.

Simulated Y-site compatibility of atosiban acetate with selected intravenous drugs.

OBJECTIVE: The physical compatibility of atosiban and selected drugs during simulated Y-site administration was evaluated. We also searched for any compatibility predictions regarding its physicochemical properties. STUDY DESIGN: Test admixtures were prepared by mixing 5 mL of each study drug solution with 5 mL of atosiban solution in a 1:1 ratio to simulate Y-site infusion. Assessments were made immediately after mixing (baseline), and at 0.5, 1, and 3 h. Visual incompatibility was defined as a presence of haze or any visible particulate matter, gas formation, or colour change. Turbidity and pH variation of the admixtures were also assessed using instrumental methods. RESULTS: None of the admixtures used with atosiban exhibited visual changes and no incompatibility regarding instrumental methods were observed, because no admixture had an increase of 0.5 nephelometric turbidity units, and no pH change was above one unit when compared to baseline. However, the pH of ampicillin and omeprazole admixtures fell outside of the atosiban stability range. CONCLUSIONS: Our study showed no physical incompatibility between atosiban and the test drugs in terms of visual changes or nephelometric and pH measurements. However, we recommend against atosiban and ampicillin or omeprazole coadministration until complementary compatibility studies are performed.

Safety and effectiveness of ferric carboxymaltose intravenous therapy in pediatric patients with chronic kidney disease.

Iron-deficiency anemia is the most common reason for worsening of the anemia characteristically seen in chronic kidney disease (CKD). Ferric carboxymaltose (FCM) is a macromolecular hydroxide ferric carbohydrate complex that allows high-dose iron to be administered parenterally for gradual, controlled release. The aim of this study was to retrospectively evaluate the safety and effectiveness of FCM treatment in pediatric patients with CKD non-dependent of hemodialysis, seen at a tertiary hospital. Data were collected on demographics, dosage, infusion time, laboratory results, and tolerability of the medicinal product. A total of 79 patients (40.5% girls) were included; the median age [25th percentile (P25) to 75th percentile (P75)] was 9 years (5-13). Laboratory results at 15-45 days post-infusion revealed a median increase of 1.4 g/dL (0.9-1.9) in hemoglobin, 224 µg/L (136-378.5) in ferritin, 37 µg/dL (17.5-71) in serum iron, and 18% (9.3-27.8) in transferrin saturation. All patients tolerated FCM infusions well, and no serious hypersensitivity reactions or anaphylactic reactions were observed. Only one adverse event was identified: drug extravasation at the end of the infusion in a 16-year-old patient. These data provide further evidence for the use of FCM as a safe and effective therapeutic option in pediatric patients with CKD, based on the low incidence of adverse effects, minor intervention required, and anemia improvement based on laboratory results.

Method for identification and quantification of intact teduglutide peptide using (RP)UHPLC-UV-(HESI/ORBITRAP)MS.

Teduglutide (Revestive®, 10 mg mL-1) is a recombinant human glucagon-like peptide 2 analogue, used in the treatment of short bowel syndrome, a serious and highly disabling condition which results from either too small a length of intestine or loss of critical intestinal function. The determination of therapeutic compounds of protein-nature is always challenging due to their complex structure. In this work, we present a fast, straightforward reversed phase (RP)UHPLC-UV-(HESI/ORBITRAP)MS method for the identification and quantification of the intact teduglutide peptide. The method has been developed and validated in accordance with the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines; therefore, linearity, limits of detection and quantification, accuracy (precision and trueness), robustness, system suitability and specificity using the signal from the UV and MS, have been evaluated. The validation performance parameters obtained from the UV and MS signals were compared throughout the work, to select the most suitable. To study the specificity of the method and the impact of medicine mishandling under hospital conditions, force degradation studies were performed, i.e. thermal (40 °C and 60 °C), shaking (mechanical) and light (accelerated exposition) effects. Identification by the exact mass of teduglutide was achieved and it was confirmed that the peptide does not undergo any post-translational modifications (PTMs). To the best of our knowledge, the present work reports the first method developed for the simultaneous identification, structural characterization, and quantification of the therapeutic teduglutide peptide. Finally, the proposed method is able to indicate stability when quantifying the intact teduglutide since detects and characterises the exact mass of the degradation/modification products.

Tracking the physicochemical stability of teduglutide (Revestive®) clinical solutions over time in different storage containers.

Teduglutide, the active ingredient of the medicine Revestive® (5 mg), is a recombinant therapeutic peptide that mimics the effects of the endogenous glucagon-like peptide 2 (GLP-2). It stimulates intestinal growth, adaptation and function in patients with Short Bowel Syndrome who are dependent on parenteral nutrition. The Summary of Product Characteristics recommends immediate use of the reconstituted solutions and the discarding of any subsequent surplus. This study aims to carry out a long-term stability study that reproduces hospital conditions of use which provide sound evidence regarding the use of teduglutide surplus beyond the Summary Product Characteristics recommendations. We conducted a stability study of teduglutide solutions prepared from a 5 mg vial of Revestive®. Some of the solutions were stored in their original vial after reconstitution, while others were repackaged in plastic syringes to evaluate their physicochemical stability over time. For this purpose, we applied a set of previously validated analytical methodologies to evaluate the main critical quality attributes of teduglutide, i.e., primary (including post-tralational modifications), secondary and tertiary structures, aggregates, particulate, concentration and pH. The results indicate that the solutions maintain high physicochemical stability over time, regardless of the storage temperature (4ºC or -20ºC) or the storage container (vials or syringes). This research provides new data on the stability of Revestive® that will be of great value to hospital pharmacists. This comprehensive assessment of the physicochemical long-term stability of TGT has demonstrated that under the storage conditions and over the period studied here, the medicine maintains its quality, efficacy and safety profiles.

Nutritional value of commercial and traditional lettuce (Lactuca sativa L.) and wild relatives: Vitamin C and anthocyanin content.

Lettuce is the most consumed leafy vegetable though the most popular varieties have a low nutritional value. Our objective was to accurately quantify vitamin C and anthocyanins in wild relatives, and commercial and traditional varieties. Wild species and traditional varieties contained more total ascorbic acid (TAA) than commercial varieties (21% and 8%, respectively). In contrast, commercial varieties had significantly higher content of anthocyanins than traditional varieties and wild species (6 and 8 times more, respectively). TAA was significantly higher in green than in red lettuces (18%). TAA was also significantly higher in the leaves of two wild species than in stems. Cyanidin 3-O-(6'-O-malonylglucoside) was the most abundant anthocyanin (97%), present in most samples. The rankings of accessions by vitamin C and anthocyanin contents can be useful for consumers worried about the impacts of food on their wellbeing and for breeders aiming to improve lettuce by biofortification with health-promoting compounds.

Improved UPLC-UV Method for the Quantification of Vitamin C in Lettuce Varieties (Lactuca sativa L.) and Crop Wild Relatives (Lactuca spp.).

Vitamins, especially vitamin C, are important micronutrients found in fruits and vegetables. Vitamin C is also a major contributor to their antioxidant capacity. Lettuce is one of the most popular vegetables among consumers worldwide. An accurate protocol to measure vitamin C content in lettuce and other related species is crucial. We describe here a method using the ultra-high-performance liquid chromatography-ultraviolet (UPLC-UV) technique, in which sample preparation, vitamin extraction and chromatography conditions were optimized. Samples were collected to represent the entire plant, frozen at -80 °C and lyophilized to prevent undesirable oxidation and make their manipulation easier. The extraction of vitamin C was carried out in acidic media, which also contributed to its stability. As vitamin C can be present in two different interconvertible forms, ascorbic acid (AA) and dehydroascorbic acid (DHAA), both compounds should be measured for accurate quantification. The DHAA was quantified indirectly after its reduction to AA because AA shows a higher absorptivity than DHAA in the UV range of the spectrum. From the same extract, two measurements were carried out, one before and one after that reduction reaction. In the first case, we were quantifying the AA content, and in the second one, we quantified the sum of AA and DHAA (TAA: total ascorbic acid) in the form of AA. Then, DHAA quantity was indirectly obtained by subtracting AA coming from the first measurement from TAA. They were determined by UPLC-UV, using a commercial AA standard to build a calibration curve and optimizing the chromatographic procedure, to obtain AA peaks that were completely resolved in a short time. This protocol could be easily extrapolated to any other plant material with slight or no changes. Its accuracy revealed statistically significant differences otherwise unperceived. Other strengths and limitations are discussed more in depth in the manuscript.