Development and Validation of a Headspace GC-MS Method for Simultaneous Quantification of Antimicrobial Preservatives in Biopharmaceutical Peptide Formulations.

The four most used antimicrobial preservatives in biopharmaceutical parenteral formulations are phenol, meta-cresol, chlorobutanol, and benzyl alcohol. Preservatives are included in various combinations in biopharmaceuticals highlighting the importance of an analytical method to quantify the four preservatives simultaneously. A headspace GC-MS method was developed to quantify phenol, chlorobutanol, meta-cresol, and benzyl alcohol.

The role of disease modifying therapies in late-onset multiple sclerosis: A Portuguese multicentric characterization study.

Introduction: Knowledge about the effect of disease modifying treatment (DMT) in late-onset multiple sclerosis (LOMS, onset ≥50 years-old) is scarce. This study aims to evaluate the association between DMT use and multiple sclerosis (MS) evolution in a LOMS cohort.

Methods: This multicentre, retrospective and observational study included LOMS patients with ≥2 years of follow-up.

Nitrosamine mitigation: NDMA impurity formation and its inhibition in metformin hydrochloride tablets.

The mitigation of nitrosamine formation in drug products has been studied and approaches such as using formulations with pH modifiers and antioxidants have been shown to decrease the formation of nitrosamines. However, more studies are needed to explore the effectivness of mitigation strategies with different drug models and formulations. The primary objective of this work was to assess the role of different antioxidants and pH modifiers in tablet formulations to mitigate the formation of NDMA, prepared in-house, using metformin hydrochloride as a model drug.

Evaluation of the bioavailability of a Tamiflu taste-masking pediatric formulation using a juvenile pig model and LC-MS/MS.

To improve the palatability and increase compliance in pediatric patients, different taste-masking technologies have been evaluated to support the NIH Pediatric Formulation Initiative. This bioavailability approach combined a juvenile porcine model which represented the pediatric population, and an advanced UHPLCMS/MS method. Juvenile pigs were administered with either commercial Tamiflu or its taste-masking formulation and plasma samples were obtained from 0 to 48 h.

Analytical Procedure Development and Proposed Established Conditions: A Case Study of a Mass Spectrometry Based NDSRI Analytical Procedure.

With the finalization of the ICH Q14 Analytical Procedure Development guideline, how to apply enhanced approaches (such as analytical quality by design (AQbD)) to develop an analytical procedure, and to propose Established Conditions (ECs) and corresponding reporting categories, is increasingly being discussed. To gain practical experience in applying an enhanced approach for method development and identifying ECs, we developed, validated, and implemented an analytical procedure for a nitrosamine drug substance-related impurity (NDSRI). Here, as an example of the application of Q12 Lifecycle Management guideline principles in regards to analytical procedures, we briefly elaborate how: 1) the principles documented in the ICH Q14 guideline for analytical procedure development were applied, with the focus on identifying an Analytical Target Profile (ATP), knowledge management and risk assessment; 2) analytical procedure robustness according to the recommendations in ICH Q2(R2) Validation of Analytical Procedure guideline and Q14, were evaluated; and 3) mass spectrometry ECs and associated proposed reporting categories were proposed.

Gender Disparities in the Academic Performance of Neurology Residents in Portugal.

Implicit bias has been linked to gender disparities in medical careers, impacting not only access to leadership positions but also early career opportunities. We aimed to evaluate if there were differences in the assessment of Neurology residents according to gender. We collected publicly available grades and rankings of two major evaluations that residents are submitted to, one at the beginning and another at the end of the neurology residency program, the National Board Exam and neurology examination, respectively.

Analysis of Genes Involved in Oxidative Stress and Iron Metabolism in Heart Failure: A Step Forward in Risk Stratification.

Introduction: Heart failure (HF) is a clinical syndrome characterized by cardinal symptoms that may be accompanied by signs. It results from structural and/or functional abnormalities of the heart leading to elevated intracardiac pressures and/or inadequate cardiac output at rest and/or during exercise. The prevalence of iron deficiency and anemia justifies the current guidelines recommendation of screening.

Antioxidants had No Effects on the In-Vitro Permeability of BCS III Model Drug Substances.

Reformulation with addition of antioxidants is one potential mitigation strategy to prevent or reduce nitrosamine drug substance-related impurities (NDSRIs) in drug products. To explore whether there could be other approaches to demonstrate bioequivalence for a reformulated oral product, which typically needs in vivo bioequivalence studies to support the changes after approval, the effects of antioxidant on the in vitro permeability of BCS III model drug substances were investigated to see whether there could be any potential impact on drug absorption. Six antioxidants were screened and four (ascorbic acid, cysteine, α-tocopherol and propyl gallate) were selected based on their nitrosamine inhibition efficiencies.

Ancestry of the major long-range regulatory site of the α-globin genes in the Portuguese population with the common 3.7 kb α-thalassemia deletion.

Background: The α-Major Regulatory Element (α-MRE), also known as HS-40, is located upstream of the α-globin gene cluster and has a crucial role in the long-range regulation of the α-globin gene expression. This enhancer is polymorphic and several haplotypes were identified in different populations, with haplotype D almost exclusively found in African populations. The purpose of this research was to identify the HS-40 haplotype associated with the 3.

Fast but not furious: Rapid ocrelizumab infusion as a strategy to optimize multiple sclerosis patients' management.

Objectives: Multiple sclerosis clinicians are continuously challenged to be innovative in delivering therapies and there is ongoing pressure to maximize day-hospital vacancies. We describe our single-center experience with ocrelizumab (OCR) rapid infusion (OCR-RI) in patients with MS (pwMS).

Methods: For pwMS with prior exposure to OCR standard infusion (OCR-SI) for at least one year/two cycles, infusion time was reduced from 3.

From Stress to Sick(le) and Back Again-Oxidative/Antioxidant Mechanisms, Genetic Modulation, and Cerebrovascular Disease in Children with Sickle Cell Anemia.

Sickle cell anemia (SCA) is a genetic disease caused by the homozygosity of the :c.20A>T mutation, which results in the production of hemoglobin S (HbS). In hypoxic conditions, HbS suffers autoxidation and polymerizes inside red blood cells, altering their morphology into a sickle shape, with increased rigidity and fragility.

Hypophosphatemia as a possible biomarker for epileptic seizures at the emergency department.

Introduction: Hypophosphatemia seems to be temporally associated with seizures, despite not being considered a trigger. We aimed to evaluate hypophosphatemia as a biomarker for seizures.

Methods: Retrospective study, including all consecutive patients admitted at our central hospital's emergency department from 01/01-31/03/2021, screened as "altered consciousness/syncope" or "seizures", with available phosphate levels.

Asymmetrical Flow Field Flow Fractionation for Molar Mass Characterization of Polyethylene Oxide in Abuse-Deterrent Formulations.

High molar mass polyethylene oxide (HM-PEO) is commonly used to enhance the mechanical strength of solid oral opioid drug products to deter abuse. Because the properties of PEO depend on molar mass distribution, accurately determining the molar mass distribution is a necessary part of understanding PEO's role in abuse-deterrent formulations (ADF). In this study, an asymmetrical flow field-flow fractionation (AF4) analytical procedure was developed to characterize PEO polymers with nominal molar masses of 1, 4 or 7 MDa as well as those from in-house prepared placebo ADF.

Bumetanide as a Model NDSRI Substrate: N-nitrosobumetanide Impurity Formation and its Inhibition in Bumetanide Tablets.

Nitrosamine compounds are classified as potential human carcinogens, the origin of these impurities can be broadly classified in two categories, nitrosamine impurity found in drug products that are not associated with the Active Pharmaceutical Ingredient (API), such as N-nitrosodimethylamine (NDMA) or nitrosamine impurities associated with the API, such as nitrosamine drug substance-related impurities (NDSRIs). The mechanistic pathway for the formation of these two classes of impurities can be different and the approach to mitigate the risk should be tailored to address the specific concern. In the last couple of years number of NDSRIs have been reported for different drug products.

A Spike-Control Approach that Evaluates High Resolution Mass Spectrometry-Based Sequence Variant Analytical Method Performance for Therapeutic Proteins.

An amino acid sequence variant (SV) is defined as an unintended amino acid substitution in protein drug products. SVs contribute to product heterogeneity and can potentially impact product quality, safety, immunogenicity, and efficacy. The analysis of biotherapeutics for SVs is important throughout the product life cycle including clone selection, development of nutrient feed strategies, commercial manufacturing process, and post-approval changes to monitor product quality.

Prevalence Rate of Thalassemia Carriers among Individuals with Microcytosis or Hypochromia in Portugal.

Introduction: Microcytosis and hypochromia result from deficient hemoglobin synthesis in red blood cells and are easily detected in a complete blood count test. These conditions are mainly due to iron nutritional deficiency, but may also result from some genetic diseases, such as thalassemia. The aim of this study was to determine the contribution of β- and α-thalassemia to these abnormal hematological phenotypes in a representative sample of adult individuals living in Portugal who participated in the first Portuguese National Health Examination Survey (INSEF).

Neuropsychological Assessment in the Distinction Between Biomarker Defined Frontal-Variant of Alzheimer's Disease and Behavioral-Variant of Frontotemporal Dementia.

Background: Frontal-variant of Alzheimer's disease (fvAD) was purposed for patients with AD pathology that, despite the typical amnestic presentation, show early and progressive deterioration of behavior and executive functions, closely resembling the behavioral-variant of frontotemporal dementia (bvFTD). This leads to a challenging differential diagnosis where neuropsychological evaluation and in vivo pathological evidence are essential.

Objective: To evaluate the contribution of a comprehensive neuropsychological assessment (NP) battery in distinguishing between fvAD-dementia and bvFTD supported by cerebrospinal fluid (CSF) biomarkers.

Rapid Quantitation of Four Nitrosamine Impurities in Angiotensin Receptor Blocker Drug Substances.

Starting in July 2018, the FDA alerted patients and health care professionals to the recall of ARBs such as valsartan by several pharmaceutical companies because of their potential contamination with carcinogenic nitrosamine impurities, including: (1) N-nitrosodimethylamine (NDMA), (2) N-nitrosodiethylamine (NDEA), (3) N-nitrosoethylisopropylamine (NEIPA), (4) N-nitrosodiisopropylamine (NDIPA), (5) N-nitrosodibutylamine (NDBA) and (6) N-nitroso-N-methyl-4-aminobutyric acid (NMBA). The FDA initiated a laboratory investigation to develop analytical procedures to test multiple lots of marketed ARB drugs to determine the possible presence of carcinogenic impurities and, if present, quantitate the levels of these impurities. Here the FDA laboratory developed and validated an automated micro-solid phase extraction MS/MS method, where all the analytes are not separated prior to elution to the MS, to simultaneously quantify NEIPA, NDIPA, NDBA and NMBA in ARB drug substances with an instrument sample analysis time of 12 seconds.

Portuguese version of the CDR plus NACC FTLD: Validation studies.

Introduction: The CDR Dementia Staging Instrument PLUS National Alzheimer's Coordinating Center (CDR plus NACC FTLD) was developed by adding to the standard CDR two extra domains focused on the main features of frontotemporal lobar degeneration (FTLD): language and behavior/personality. We intended to perform the validation studies for the European-Portuguese population.

Methods: A total of 105 participants matched for age, education, and disease staging (35 bvFTD, 35 AD, and 35 controls) were included.