Publications by authors named "Gabriel Marcelin Jimenez"

We recently reported the isolation and characterization of an anti-SARS-CoV-2 antibody, called IgG-A7, that protects transgenic mice expressing the human angiotensin-converting enzyme 2 (hACE-2) from an infection with SARS-CoV-2 Wuhan. We show here that IgG-A7 protected 100% of the transgenic mice infected with Delta (B.1.

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Aim: Cinitapride (CIN) is a benzamide-derived molecule used for the treatment of gastroesophageal reflux and dyspepsia. Its pharmacokinetics are controversial due to the use of supratherapeutic doses and the lack of sensitive methodology. Therefore, a sensitive and accurate micromethod was developed for its quantitation in human plasma.

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Background: Sildenafil is used for the treatment of pediatric pulmonary hypertension. A dried blood spot (DBS)-based LC-MS method for sildenafil quantitation was developed and applied to a group of patients.

Results: DBS showed high portability and stability of samples, and the method was selective and linear for quantitation of sildenafil (5-3,000 ng/ml) and N-desmethyl-sildenafil (3-1,500 ng/ml).

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Consensus practices and regulatory guidance for liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) assays of small molecules are more aligned globally than for any of the other bioanalytical techniques addressed by the Global Bioanalysis Consortium. The three Global Bioanalysis Consortium Harmonization Teams provide recommendations and best practices for areas not yet addressed fully by guidances and consensus for small molecule bioanalysis. Recommendations from all three teams are combined in this report for chromatographic run quality, validation, and sample analysis run acceptance.

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Background: Nitazoxanide (NTZ) is used for the treatment of gastrointestinal tract colonization by anaerobic bacteria, viruses and other pathogens that represent a major cause of morbidity in Latin America. The aim of the present work was to develop and validate a UPLC-MS/MS method for the selective quantification of tizoxanide (TZN, the major metabolite of NTZ) in human plasma using niclosamide as internal standard; and examine its pharmacokinetic application in healthy volunteers. Nine male subjects received a single oral dose of a NTZ 500-mg tablet under fasting conditions.

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Background: Sildenafil citrate (SIL) was the first oral drug registered in Mexico for the treatment of erectile dysfunction. However, succinct pharmacokinetic data are available in the Mexican population.

Objective: The goals of the present work were: (1) to design a specific method to quantify SIL plasma levels by using UPLC-MS/MS; (2) to compare oral SIL bioavailability in Mexican men with pharmacokinetic data in other populations; (3) to fulfill local regulatory requests; and (4) to describe the relative tolerability of a new 50-mg chewable tablet.

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Background: A growing number of boron-containing compounds exhibit many important biological activities; of particular interest are the α-amino acid borinic derivatives with activity in the CNS. A validated, sensitive and specific UPLC-MS/MS technique for quantification of the diphenylboroxazolidones of glycine (DBPX-gly), L-aspartate (DPBX-L-asp) and L-glutamate (DPBX-L-glu) in dried blood spots (DBSs) is presented.

Results: The most intense signal corresponds to compounds with (11)B.

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Background: Valproic acid has been associated with a highly variable intersubject absorptive phase; therefore, magnesium salt (magnesium valproate [MgV]) was developed to diminish variation during enteric absorption.

Objectives: The aims of this study were to assess the pharmacokinetics of single oral doses of MgV 500-mg solution, suspension, and enteric-coated tablets in a healthy Mexican population, and to compare formulation-related differences.

Methods: This was a randomized, single-dose, 3-period, 6-sequence crossover study in healthy Mexican volunteers aged 18 to 45 years.

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Background: The aim of the present work was to develop a chromatographic technique coupled with mass spectrometry for the measurement of lamotrigine in plasma. Lamotrigine and guanabenz (internal standard) were measured by selected reaction monitoring. The method was validated and applied in a bioequivalence trial on 26 female volunteers.

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Pharmacokinetics of diphenidol (DPN) is limited due to the lack of analytical methodology. Here, a micro-assay for DPN quantification was developed, by coupling ultra-performance liquid chromatography with tandem mass spectrometry. The procedure involved plasma precipitation and injection of supernatant into UPLC with an Acquitytrade mark C18 column.

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Objective: The aim was to develop a rapid, specific, sensitive and accurate chromatographic technique coupled with mass spectrometry for the measurement of tacrolimus (CAS 104987-11-3) in microsamples of whole blood, and its application on a pharmacokinetic pilot trial.

Methods: A fast gradient was designed in an ultra-performance liquid chromatography, and coupled with a mass spectrometer for the quantification of tacrolimus in 100 microl samples of EDTA whole blood. Multiple reaction monitoring was used for the measurement of tacrolimus (m/z(+1) 821.

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Background: and objective: In Mexico, urinary tract infections (UTIs) constitute the second most frequent type of infections treated at primary-care clinics. Ciprofloxacin has played a major role in the treatment of UTIs because it has a broad spectrum of antibacterial activity. In addition to antimicrobial agents, phenazopyridine has been used to alleviate symptoms that occur during episodes of UTI.

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