Alexander Lopez-Roblero

Prof. Alexander Lopez-Roblero

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 February 2021 in PLOS Neglected Tropical Diseases
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PBPablo F. Belaunzarán-Zamudio
Pablo F. Belaunzarán-Zamudio
AMAllyson Mateja
Allyson Mateja
PDPaola del Carmen Guerra- de-Blas
Paola del Carmen Guerra- de-Blas
HRHéctor A. Rincón-León
Héctor A. Rincón-León
KNKarla Navarro-Fuentes
Karla Navarro-Fuentes
T(the Mexican Emerging Infectious Diseases Clinical Research Network (LaRed)
the Mexican Emerging Infectious Diseases Clinical Research Network (LaRed)
Background: Our purpose was to provide a detailed clinical description, of symptoms and laboratory abnormalities, and temporality in patients with confirmed Zika and dengue infections, and other acute illnesses of unidentified origin (AIUO). Methods/ Principal findings: This was a two-year, multicenter, observational, prospective, cohort study. We collected data from patients meeting the Pan American Health Organization’s modified case-definition criteria for probable Zika infection. We identified Zika, dengue chikungunya by RT-PCR in serum and urine. We compared characteristics between patients with confirmed Zika and dengue infections, Zika and AIUO, and Dengue and AIUO at baseline, Days 3,7,28 and 180 of follow-up. Most episodes (67%) consistent with the PAHO definition of probable Zika could not be confirmed as due to any flavivirus and classified as Acute Illnesses of Unidentified Origin (AIUO). Infections by Zika and dengue accounted for 8.4% and 16% of episodes. Dengue patients presented with fever, generalized non-macular rash, arthralgia, and petechiae more frequently than patients with Zika during the first 10 days of symptoms. Dengue patients presented with more laboratory abnormalities (lower neutrophils, lymphocytosis, thrombocytopenia and abnormal liver function tests), with thrombocytopenia lasting for 28 days. Zika patients had conjunctivitis, photophobia and localized macular rash more frequently than others. Few differences persisted longer than 10 days after symptoms initiation: conjunctivitis in Zika infections, and self-reported rash and petechia in dengue infections. Conclusions: Our study helps characterize the variety and duration of clinical features in patients with Zika, dengue and AIUO. The lack of diagnosis in most patients points to need for better diagnostics to assist clinicians in making specific etiologic diagnoses.

1 July 2019 in Disease Markers
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LCLuis Miguel Canseco-Avila
Luis Miguel Canseco-Avila
ALAlexander Lopez-Roblero
Alexander Lopez-Roblero
ESEleazar Serrano-Guzman
Eleazar Serrano-Guzman
JAJavier Aguilar-Fuentes
Javier Aguilar-Fuentes
CJCarlos Jerjes-Sanchez
Carlos Jerjes-Sanchez
RORocio Ortiz-Lopez
Rocio Ortiz-Lopez
Some polymorphisms in genes codifying for fibrinogen have been correlated with plasma levels of this protein, and several studies reported their associations with acute cardiovascular events. In the present study, 118 subjects with unstable and stable coronary diseases were enrolled to determinate the associations among fibrinogen gene polymorphisms, plasma fibrinogen levels, and major cardiovascular adverse events in a sample of southwestern Mexico. The groups, including 81 control subjects, were matched for age, sex, body mass index, and sedentarism. Plasma fibrinogen levels and the polymorphisms 455G/A, -148C/T, +1689T/G, andBclI of the gene of fibrinogen were compared in all groups. Plasma fibrinogen levels (>465 mg/dl) were significant in patients with coronary disease.Fibrinogen plasma values>450 mg/dlwere associated with cardiovascular mortality during the follow-up analysis of the unstable coronary disease group (p=0.04). The allelic loads of -455A and -148T were associated withplasma fibrinogen levels>450 mg/dl(p<0.003andp=0.03, respectively) and with coronary disease (p=0.016andp<0.006, respectively). The follow-up of posterior events after an acute coronary event showed that the genetic load of the -148T allele was associated with major adverse cardiovascular events (RR=1.8,95%CI=1.01‐3.35,p=0.04).Fibrinogen plasmatic levels>450 mg/dland the fibrinogen polymorphisms -455G/A and 148C/T had association with MACE and coronary disease. This study suggests that these gene polymorphisms are associated with cardiovascular risk.

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ARAdriana Galvez Ramirez
Adriana Galvez Ramirez
AGAbigail González-Valdez
Abigail González-Valdez
BHBeatriz Hernandez-Ochoa
Beatriz Hernandez-Ochoa
LCLuis Miguel Canseco-Avila
Luis Miguel Canseco-Avila
ALAlexander Lopez-Roblero
Alexander Lopez-Roblero
SGSaul Gomez-Manzo
Saul Gomez-Manzo
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an enzymopathy that affects approximately 500 million people worldwide. A great number of mutations in the G6PD gene have been described. However, three class A G6PD variants known as G6PD Tomah (C385R), G6PD Kangnam (C385G), and G6PD Madrid (C385W) have been reported to be clinically important due to their associations with severe clinical manifestations such as hemolytic anemia. Therefore, this work aimed to perform, for the first time, biochemical and functional characterizations of these variants. The G6PD variants were cloned and purified for this purpose, followed by analyses of their kinetic parameters and thermal stability, as well as in silico studies. The results showed that the mutations induced changes in the proteins. Regarding the kinetic parameters, it was observed that the three variants showed lower affinities for G6P and NADP+, as well as lower thermal stability compared to WT-G6PD. Molecular dynamics simulations showed that C385 mutations induced changes around neighboring amino acids. Metadynamics simulations showed that most remarkable changes account for the binding pocket volumes, particularly in the structural NADP+ binding site, with a concomitant loss of affinity for catalytic processes.