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RATIONALE: Since June 2018, globally large numbers of pharmaceuticals have been recalled due to the unexpected presence of nitrosamines. Beginning with the class of pharmaceuticals known as sartans, subsequent lines of inquiry included antidiabetic medicines, antihistamines, and antibiotics. A critical review of the U.S. Food and Drug Administration database reveals that the highest number of products recall due to the presence of unacceptable levels of nitrosamines were losartan potassium drug products and their coformulations with other drug substances. The problem can be mainly attributed to naively adopted approval revisions and the lack of sufficient current analytical technologies to detect those contaminants in time. In this work, we developed a specific, selective, accurate, precise, and robust ultra-performance liquid chromatography-triple quadrupole-mass spectrometry (UPLC-TQ-MS/MS) method for the estimation of eight genotoxic nitrosamine impurities in losartan and hydrochlorothiazide (HCTZ) tablets, which is the only fixed-dosage combination approved by the USFDA to treat hypertension. METHODS: All the nitrosamine impurities along with the drug substances were separated using an Agilent Pursuit XRs Ultra diphenyl column (150 × 2.0 mm, 2.8 µm) with mobile phase A (0.1% formic acid in water) and mobile phase B (0.1% formic acid in methanol) at a flow rate of 0.4 ml/min using the gradient elution program. The proposed method was validated per ICH (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use) Q2 (R1) guidelines to ensure the method is suitable for its intended purpose. RESULTS: Limit of detection and limit of quantification were obtained in the range of 0.25-0.5 ng/mL, which was very low compared to levels specified by the USFDA, European Medicines Agency (EMA), and other regulatory authorities that ensure the sensitivity of the method in its entire life cycle. CONCLUSIONS: The developed method can be incorporated into an official monograph and applied for routine quality control analysis of losartan and HCTZ fixed-dose combination tablets.
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Losartan , Nitrosaminas , Humanos , Losartan/análise , Losartan/química , Hidroclorotiazida/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , ComprimidosRESUMO
A novel stability-indicating, reversed-phase, high-performance liquid chromatography (RP-HPLC) method was developed and validated for the determination of favipiravir in an oral suspension. The effective separation of favipiravir and its degradation products was achieved on a Zorbax Eclipse Plus C18 column (5 µm particle size, 150 mm length × 4.6 mm diameter). The mobile phase was prepared by mixing 5 mM of phosphate buffer (pH 3.5) and methanol in a 75:25 v/v ratio delivered at a 1.0 mL/min flow rate. The eluents were monitored using a photodiode array detector at a wavelength of 322 nm. The stability-indicating nature of this method was evaluated by performing force degradation studies under various stress conditions, such as acidic, alkali, oxidative, thermal, and photolytic degradation. Significant degradation was observed during the alkali stress degradation condition. The degradation products generated during various stress conditions were well separated from the favipiravir peak. In addition, the major degradation product formed under alkali stress conditions was identified using UPLC-ESI-TQ-MS/MS and NMR. Method validation was performed according to the ICH Q2 (R1) guideline requirements. The developed method is simple, accurate, robust, and reliable for routine quality control analysis of favipiravir oral suspensions.
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Álcalis , Espectrometria de Massas em Tandem , Amidas , Cromatografia Líquida de Alta Pressão/métodos , Pirazinas , Suspensões , Espectrometria de Massas em Tandem/métodosRESUMO
OBJECTIVE: To compare the efficacy of low dose-short course intravenous paracetamol with a conventional dose regimen for early targeted closure of patent ductus arteriosus (PDA). DESIGN: Single-centre, double-blinded, active controlled, randomised non-inferiority trial. SETTING: Level III neonatal intensive care unit in Western India. PATIENTS: Preterm infants <30 weeks of gestation requiring mechanical ventilation, or continuous positive airway pressure with FiO2 ≥0.35 and diagnosed with a haemodynamically significant PDA (hsPDA) at 18-24 hours of postnatal age. INTERVENTIONS: Low dose (10 mg/kg/dose 6 hourly for 72 hours) versus conventional dose (15 mg/kg/dose 6 hourly for 120 hours) intravenous paracetamol treatment. MAIN OUTCOME MEASURES: Comparison of the rates of ductal closure at completion of sixth postnatal day, using a prespecified non-inferiority margin of 20%. RESULTS: A total of 102 infants were enrolled. The median gestational age and birth weight of the included infants were 26.4 weeks and 830 g. At completion of the sixth postnatal day, closure of PDA was achieved in 92% of infants in the low dose group as compared with 94% of those in the standard dose group (risk difference: -1.6%, 95% CI: -11.6% to 8.5%, p=0.38). The rates of rescue therapies, adverse effects and other neonatal morbidities were comparable in both groups. CONCLUSION: In very preterm infants on significant respiratory support, low dose-short course intravenous paracetamol treatment was non-inferior to a conventional dosing regime of paracetamol for closure of hsPDA in the first week of postnatal age. Larger studies with narrow margins of non-inferiority are required to confirm our findings. TRIAL REGISTRATION NUMBER: CTRI/2017/10/010012.
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Permeabilidade do Canal Arterial , Recém-Nascido Prematuro , Humanos , Recém-Nascido , Acetaminofen , Permeabilidade do Canal Arterial/tratamento farmacológico , Ibuprofeno/uso terapêutico , Recém-Nascido de muito Baixo Peso , Método Duplo-CegoRESUMO
INTRODUCTION: Our objective was to evaluate the temporal trend of systemic postnatal steroid (PNS) receipt in infants of 24-28 weeks' gestational age, identify characteristics associated with PNS receipt, and correlate PNS receipt with the incidence of bronchopulmonary dysplasia (BPD) and BPD/death from an international cohort included in the iNeo network. METHODS: We conducted a retrospective study using data from 2010 to 2018 from seven international networks participating in iNeo (Canada, Finland, Israel, Japan, Spain, Sweden, and Switzerland). Neonates of 24 and 28 weeks' gestational age who survived 7 days and who received PNS were included. We assessed temporal trend of rates of systemic PNS receipt and BPD/death. RESULTS: A total of 47,401 neonates were included. The mean (SD) gestational age was 26.4 (1.3) weeks and birth weight was 915 (238) g. The PNS receipt rate was 21% (12-28% across networks) and increased over the years (18% in 2010 to 26% in 2018; p < 0.01). The BPD rate was 39% (28-44% across networks) and remained unchanged over the years (35.2% in 2010 to 35.0% in 2018). Lower gestation, male sex, small for gestational age status, and presence of persistent ductus arteriosus (PDA) were associated with higher rates of PNS receipt, BPD, and BPD/death. CONCLUSION: The use of PNS in extremely preterm neonates increased, but there was no correlation between increased use and the BPD rate. Research is needed to determine the optimal timing, dose, and indication for PNS use in preterm neonates.
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Displasia Broncopulmonar , Recém-Nascido Prematuro , Lactente , Humanos , Recém-Nascido , Masculino , Estudos de Coortes , Estudos Retrospectivos , Países Desenvolvidos , Displasia Broncopulmonar/etiologia , Idade Gestacional , Corticosteroides/uso terapêuticoRESUMO
Functional measurements of the left atrium (LA) in atrial fibrillation (AF) patients is limited to a single CINE slice midway through the LA. Nonetheless, a full 3D characterization of atrial functional measurements would provide more insights into LA function. But this improved modeling capacity comes at a price of requiring LA segmentation of each 3D time point,a time-consuming and expensive task that requires anatomy-specific expertise.We propose an efficient pipeline which requires ground truth segmentation of a single (or limited) CINE time point to accurately propagate it throughout the sequence. This method significantly saves human effort and enable better characterization of LA anatomy. From a gated cardiac CINE MRI sequence we select a single CINE time point with ground truth segmentation, and assuming cyclic motion, we register other images corresponding to all time points using diffeomorphic registration in ANTs. The diffeomorphic registration fields allow us to map a given anatomical shape (segmentation) to each CINE time point, facilitating the construction of a 4D shape model.
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Abdominal aortic aneurysm (AAA) is a vascular disease characterized by the enlargement of the infrarenal segment of the aorta. A ruptured AAA can cause internal bleeding and carries a high mortality rate, which is why the clinical management of the disease is focused on preventing aneurysm rupture. AAA rupture risk is estimated by the change in maximum diameter over time (i.e., growth rate) or if the diameter reaches a prescribed threshold. The latter is typically 5.5 cm in most clinical centers, at which time surgical intervention is recommended. While a size-based criterion is suitable for most patients who are diagnosed at an early stage of the disease, it is well known that some small AAA rupture or patients become symptomatic prior to a maximum diameter of 5.5 cm. Consequently, the mechanical stress in the aortic wall can also be used as an integral component of a biomechanics-based rupture risk assessment strategy. In this work, we seek to identify geometric characteristics that correlate strongly with wall stress using a sample space of 100 asymptomatic, unruptured, electively repaired AAA models. The segmentation of the clinical images, volume meshing, and quantification of up to 45 geometric measures of each AAA were done using in-house Matlab scripts. Finite element analysis was performed to compute the first principal stress distributions from which three global biomechanical parameters were calculated: peak wall stress, 99th percentile wall stress and spatially averaged wall stress. Following a feature reduction approach consisting of Pearson's correlation matrices with Bonferroni correction and linear regressions, a multivariate stepwise regression analysis was conducted to find the geometric measures most highly correlated with each of the biomechanical parameters. Our findings indicate that wall stress can be predicted by geometric indices with an accuracy of up to 94% when AAA models are generated with uniform wall thickness and up to 67% for patient specific, non-uniform wall thickness AAA. These geometric predictors of wall stress could be used in lieu of complex finite element models as part of a geometry-based protocol for rupture risk assessment.
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Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/fisiopatologia , Modelos Cardiovasculares , Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Cirúrgicos Eletivos , Humanos , Estresse MecânicoRESUMO
This erratum is to correct the variable name on the left hand side of Eq. (2). The correct variable name is "Diameter" rather than the stated "Area."
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Abdominal aortic aneurysm (AAA) is an asymptomatic aortic disease with a survival rate of 20% after rupture. It is a vascular degenerative condition different from occlusive arterial diseases. The size of the aneurysm is the most important determining factor in its clinical management. However, other measures of the AAA geometry that are currently not used clinically may also influence its rupture risk. With this in mind, the objectives of this work are to develop an algorithm to calculate the AAA wall thickness and abdominal aortic diameter at planes orthogonal to the vessel centerline, and to quantify the effect of geometric indices derived from this algorithm on the overall classification accuracy of AAA based on whether they were electively or emergently repaired. Such quantification was performed based on a retrospective review of existing medical records of 150 AAA patients (75 electively repaired and 75 emergently repaired). Using an algorithm implemented within the MATLAB computing environment, 10 diameter- and wall thickness-related indices had a significant difference in their means when calculated relative to the AAA centerline compared to calculating them relative to the medial axis. Of these 10 indices, nine were wall thickness-related while the remaining one was the maximum diameter (Dmax). Dmax calculated with respect to the medial axis is over-estimated for both electively and emergently repaired AAA compared to its counterpart with respect to the centerline. C5.0 decision trees, a machine learning classification algorithm implemented in the R environment, were used to construct a statistical classifier. The decision trees were built by splitting the data into 70% for training and 30% for testing, and the properties of the classifier were estimated based on 1000 random combinations of the 70/30 data split. The ensuing model had average and maximum classification accuracies of 81.0 and 95.6%, respectively, and revealed that the three most significant indices in classifying AAA are, in order of importance: AAA centerline length, L2-norm of the Gaussian curvature, and AAA wall surface area. Therefore, we infer that the aforementioned three geometric indices could be used in a clinical setting to assess the risk of AAA rupture by means of a decision tree classifier. This work provides support for calculating cross-sectional diameters and wall thicknesses relative to the AAA centerline and using size and surface curvature based indices in classification studies of AAA.
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Aneurisma da Aorta Abdominal/classificação , Árvores de Decisões , Modelos Cardiovasculares , Algoritmos , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Humanos , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: A new, simple, selective, precise, and stability-indicating high-performance thin-layer chromatographic method has been established for analysis of itraconazole (ITZ) in the bulk drug and in pharmaceutical formulations. Separation was achieved on aluminium plate precoated with silica gel 60F254 using Toluene : Chloroform : Methanol [5: 5: 1.5(v/v)] as mobile phase. Densitometric analysis was performed at 260 nm. RESULT: Compact bands of ITZ were obtained at Rf 0.52 ± 0.02. Linearity (R(2) = 0.9978), limit of detection (180.29 ng/band), limit of quantification (546.34 ng/band), recovery (98-102%), and precision (≤0.51%) were satisfactory. Drug was not degraded under neutral and alkaline hydrolysis, UV and photolytic degradation, under-elevated temperature, and humidity. ITZ is degraded under acidic hydrolysis and oxidative condition; the degraded products were well resolved from individual bulk drug response. Developed method can effectively resolve drug from its excipients in capsule dosage form. The specificity of the method was confirmed by peak purity of resolved peak. CONCLUSION: The method can be applicable for routine analysis of ITZ in pharmaceutical formulation as stability-indicating. Because the method can effectively separate the drug from its degradation products as well as excipients, it can be used as a stability-indicating method.