Roberto Lozano - Academia.edu (original) (raw)

Papers by Roberto Lozano

A case-control pharmaco-epidemiological study, aimed to identify the drug class and/or duration o... more A case-control pharmaco-epidemiological study, aimed to identify the drug class and/or duration of treatments causing hyposideremia, was carried out. For this, the prescription medicines of all patients addmited to a Internal Medicine service, for various indications, along a 1-year period (2019), were recorded and, ultimately, its association to hyposideremia analyzed. As a result, it was identified several drugs associated with alterations in serum iron levels: acetylcysteine, apixaban and edoxaban, which would increase the risk of hyposideremia. On the contrary, we found that allopurinol, duloxetine and simvastatin would protect against the appearance of hyposideremia. These drugs, alone or in combination with different pathologies, would be capable of inducing, and on dependence of the duration of treatment and/or of the concomitant pathology, hyposideremia, iron deficiency and, in certain cases, anemia constituting a major health problem.

Dear editor During recent years, statins have been used to reduce serum cholesterol levels, but w... more Dear editor During recent years, statins have been used to reduce serum cholesterol levels, but with conflicting results concerning the benefits obtained in women compared with men in the prevention of cardiovascular events.1 Some authors have suggested that the state of inflammation, assessed by the concentration of C-reactive protein (CRP), determines the protective vascular effects of statin therapy. It has been reported that statins might be more beneficial in people with elevated CRP levels, and may be inef-fective in people with low concentrations of both CRP and low-density lipoprotein cholesterol.2 Furthermore, other authors have reported higher levels of CRP in women than in men.3 Gutierrez et al1 observed lower preventive efficacy of statins in women, and Emberson et al2 concluded that the greatest benefit from taking statins is obtained when CRP levels are elevated, which is inconsistent with the fact that women have higher levels of CRP. At this point, we would like to j...

Which people should take aspirin for primary prevention of cardiovascular disease?

Journal of Advances in Medical and Pharmaceutical Sciences, 2020

Aim: To identify the drug class and/or duration of treatments causing hyposideremia. Study Design... more Aim: To identify the drug class and/or duration of treatments causing hyposideremia. Study Design: Retrospective case-control study. Place and Duration of Study: Departments of Internal Medicine and Pharmacy, Aragón Health Services Services Hospital Real de Nuestra Señora de Gracia, between January 2019 and December 2019. Methodology: The records of prescripted medicines of all patients admitted to Internal Medicine service, for various indications, along a 1-year period (2019), which were ultimately analized according to association with hyposideremia. Results: It was identified several drugs associated with low plasma iron levels: acetylcysteine and apixaban, which would increase the risk of hyposideremia. On the contrary, we found that allopurinol, duloxetine and simvastatin would protect against the appearance of hyposideremia. Conclusion: Acetylcysteine and apixaban, alone or in combination with different pathologies, would be capable of inducing, and on dependence of the dur...

Int. Journal of Clinical Pharmacology and Therapeutics, 2017

A frequency shift in a circularly polarized beam of light rotating with an angular velocity with ... more A frequency shift in a circularly polarized beam of light rotating with an angular velocity with respect to the observer can be induced by the lens moving in a circular path in a purely optical experiment. Based on this rotational Doppler effect, obtained when a polarized beam of light with angular momentum passes through a rotating optic object, a theoretical model is developed for the relationship between this frequency shift and the rotational velocity of the lenses. The obtained equation relates the generated coordinate acceleration to this rotational Doppler effect of a circularly polarized electromagnetic wave, caused by the transfer of spin angular momentum from a rotating object. That mathematical relation is resolved in the context of a four-dimensional Minkowski flat space and Cartesian coordinates. The mentioned rotational Doppler shift would generate a difference in coordinate acceleration in the counter-propagating direction in which the photons move, due to the differe...

Current Clinical Pharmacology, 2020

Background: Successful integration of in vitro into in vivo data on drug-drug interaction (DDI) i... more Background: Successful integration of in vitro into in vivo data on drug-drug interaction (DDI) is dependent on the inhibitory concentration used. Obtaining plasma concentration of a drug is only readily available for a small number of drugs in clinical practice, and so we propose the use of a therapeutic range as a substitute for inhibitory concentration. Objective: Because of this, we aimed to construct a linear-regression model based on the area-under-curve of the victim drugs and the therapeutic range, for a set of known inhibitors of the CYP2D6 of interest. Methods: Correlation analysis of linear log-log regression of two main variables: the area-under-curve ratio (AUCr) of the victim drugs and of the therapeutic range-to-inhibition constant ratio, with data obtained from literature. Results: Data were fitted to a linear log-log regression, between the average of the AUCr values and the mean value of the therapeutic range-to-inhibition constant ratio (TRm-to-Ki), of the inhibit...

Aripiprazole is a second generation atypical antipsychotic (AAP), with properties of partial dopa... more Aripiprazole is a second generation atypical antipsychotic (AAP), with properties of partial dopamine agonist, used in schizophrenia, bipolar disorder and depression, among others. On the other hand, the side effects associated with AAP treatment are drug-specific, with hyperprolactinemia and metabolic syndrome being some of the most important. Hyperprolactinemia is an adverse effect with consequences both in the short term, alterations in gonadal function and parkinsonism, and in the long term, osteopenia-osteoporosis, metabolic syndrome and / or increased thromboembolic risk. Therefore, normalization or reduction of prolactinemia is sufficient to avoid them. According to our results, aripiprazole would be the ideal component for the combined treatment with those other antipsychotics that cause hyperprolactinemia, such as risperidone, reducing it and alleviating or eliminating the adverse effects derived from chronic hyperprolactinemia.

Linear regression-based model between area-under-curve (AUCr) and thetherapeutic range-to-inhibit... more Linear regression-based model between area-under-curve (AUCr) and thetherapeutic range-to-inhibition constant ratio (TR-to-Ki). As result, a linear log-log regression model,between the averaged AUCr, calculated as the mean from the values of different DDIs between severalvictim-drugs with the same inhibitor (AUCr avg), and the mean TR-to-Ki ratio (TRm-to-Ki), calculated asthe mean value between the maximum and minimum TR of the inhibitor divided by its Ki, obtained thebest correlation (r2= 0.72; p=0.0116). Accordingly, a drug-drug interaction involving reversible inhibitorydrugs of CYP2D6 could be manage by adjusting dose of victim and/or inhibitory drug to the magnitudeof the desired change, by applying data of TR and Ki of inhibitor to the equation of regression linepresented here.

Indian Journal of Psychiatry, 2019

According to these results and consulted literature, we suggest that NO produced by the action of... more According to these results and consulted literature, we suggest that NO produced by the action of NOS on Arg alternatively could react with the nitrogen in the carbamoyl group of glutamine (Gln) to generate Glu (an excitatory neurotransmitter) and N 2 gas. Glu would undergo further decarboxylation to yield GABA (an inhibitory neurotransmitter), as favored by the gas laws since two volumes of NO gas are transformed into one volume of N 2. Thus, the production of Glu plus N 2 or the production of urea would be altered by antidepressant treatment, which would promote urea production by means of inhibiting citrulline/NO synthesis from Arg. This interpretation of results is by analogy with the known reaction of ammonia combustion to yield N 2 , with NO as an intermediate product. [5] Such a reaction, in eukaryotic cells, would consist in the oxidation, by enzymatic catalysis, of the amino and amido groups contained in organic compounds (e.g., Glu) to produce NO (as an intermediate product) and finally N 2. In brief, and following the previous scheme, treatment with antidepressants would modulate the urea cycle, coupled to Gln-Glu interconversion and decarboxylation of Glu to GABA, to yield urea instead of citrulline/NO plus N 2. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Adicciones, Jan 13, 2018

Letter to the editor.

JAMA Cardiology, 2016

In Reply We appreciate the interest McAlister took in our recent article in JAMA Cardiology1 rega... more In Reply We appreciate the interest McAlister took in our recent article in JAMA Cardiology1 regarding oral anticoagulation prescription in patients with atrial fibrillation (AF) across the spectrum of stroke risk in the American College of Cardiology National Cardiovascular Data Registry Practice Innovation and Clinical Excellence Registry. The author highlights some of our main findings, including that oral anticoagulant (OAC) prescription prevalence did not surpass 50%, even in high-risk patients with a CHADS2 score greater than 3 and a CHA2DS2-VASc score greater than 4. Much of the focus of our article was on the observed underuse and plateau of OAC prescription such that half of patients with AF at moderate to high risk for stroke did not receive guideline-adherent therapy. However, the author is correct to point out that almost 1 in 3 patients at the lowest risk of stroke, with CHADS2 and CHA2DS2VASc scores of 0, also received OAC prescription. We completely agree that the appropriate prescription of anticoagulation must take both underuse and overuse into account. In fact, in a recently published study2 also using the Practice Innovation and Clinical Excellence Registry, we observed practice patterns very consistent with those referenced by McAlister. Specifically, we assessed those patients with AF at the lowest risk of stroke. Despite a contemporary guideline class III indication against anticoagulant therapy (including those younger than 60 years) at that time, approximately 25% of young and otherwise healthy patients with AF with CHADS2 and CHA2DS2-VASc scores of 0 were prescribed OAC. Older age and higher body mass index were associated with more frequent OAC prescription after multivariable adjustment.2 Not everyone with AF should receive OAC, and stroke risk scores should be used to guide these decisions. Indiscriminate OAC use introduces more risks than benefits in these patients and violates the fundamental ethic of medicine, primum non nocere (ie, “first, do no harm”). We agree that pay-for-performance programs and even clinical research funding may not incentivize efforts to elucidate this behavior, but we think it is important to support further efforts to highlight overuse as an area of needed reform.

JAMA Internal Medicine, 2016

The Journal of Clinical Psychiatry, 2016

To the Editor: Lee et al 1 studied the impact of clozapine on the erythroid lineage in a sample o... more To the Editor: Lee et al 1 studied the impact of clozapine on the erythroid lineage in a sample of schizophrenic patients and found a high incidence of anemia in the first 2 years following clozapine initiation, with smoking and baseline hemoglobin level shown to be significant protective factors. They concluded that there was a need for further studies of the relationships between schizophrenia, clozapine, and anemia. Following their observations and conclusions, we would like to note the following 2 main points: First, regarding the known dose-related clozapine toxicity, the presence of a mean plasma clozapine level above the upper limit of the therapeutic range (360-690 ng/mL) 2 among anemic patients should be highlighted. In fact, the group of anemic patients 1 presented a mean value of 771.7 ± 287.1 ng/mL (n = 7), which suggests a potentially toxic outcome, compared with a lower mean value of 575.0 ± 262.8 ng/mL (n = 19) in non-anemic patients, although the difference was not significant because of a lack of sufficient statistical power. In this regard, we know that cytochrome P450 reductase (CYP) 1A2 is the most important route of clozapine metabolism, 2 the metabolic activity of which is mediated by smoking, as it is one of most important CYP1A2 inducers. Smoking, which has been shown to have different incidences among anemic and non-anemic patients (22% vs 65%, Z = 3.6; 95% CI, 0.1967-0.6653; P < .001) according to Lee and colleagues' study, 1 is crucial for the presence of toxicity associated with high plasma clozapine levels; further, there is a proven dose-response relation between plasma concentration and the risk of adverse events. 3,4 Thus, if Lee et al 1 had submitted data on plasma clozapine level and compared smokers with nonsmokers, we would have additional information about the influence of smoking on the plasma levels of clozapine and their toxicity. Second, regarding clozapine-related anemia that presents following treatment initiation within the first 2 years, the effect of clozapine on high-sensitivity C-reactive protein (hs-CRP), an acute-phase reactant and marker of inflammation, as a possible confounder for the typing of anemia and, therefore, the attribution of its pathogenesis, should be highlighted. For example, anemia of inflammation is most commonly described as normocyticnormochromic, but it can become microcytic-hypochromic (a typical pattern of iron-deficiency anemia) or resolved in accordance with the development of the inflammatory disorder. 5 In fact, we know that clozapine, especially at the beginning, leads to increased hs-CRP unrelated to age, race, or smoking status. 6-8 Moreover, hs-CRP level is inversely related to hemoglobin level, which could result in transient anemia through hs-CRP elevation. 9,10 In this regard, observations based on post hoc comparative data analysis (2010 vs 2013), from our own previous study, 11 showed a decrease in the mean value of hs-CRP (t = 2.1786; 95% CI, 0.183-4.217; P < .05) and anemia prevalence over time (Table 1). Thus, if Lee et al 1 had submitted data on hs-CRP among anemic compared with nonanemic patients, we would have additional information about the influence of inflammatory cytokines on clozapine-related anemia. In conclusion, these data, if supplied, would have provided additional insight into the pathogenesis, diagnosis, and treatment of clozapine-related anemia.

Seleccionado en la convocatoria: Proyectos de innovacion e investigacion educativa en centros doc... more Seleccionado en la convocatoria: Proyectos de innovacion e investigacion educativa en centros docentes sostenidos con fondos publicos de niveles no universitarios, Gobierno de Aragon 2012-2013.

Journal of Clinical Psychopharmacology, 2016

To the Editors: U pon reading the study of Meehan et al, who determined the prevalence of lithium... more To the Editors: U pon reading the study of Meehan et al, who determined the prevalence of lithium-associated hyperparathyroidism (LHPT) in the Swedish population and suggested the monitoring of serum calcium ([Ca]) and parathyroid hormone (PTH) for these patients, we would like to make 2 brief comments on the basis of our own data from a study of a small cohort. This cohort comprised patients treated with lithiumwho underwent continuousmonitoring

European Journal of Solid State and Inorganic Chemistry, 1988

In this work, we describe the application of a new method to study the kinetics analysis, by diff... more In this work, we describe the application of a new method to study the kinetics analysis, by differential scanning calorimetry, on the thermal decomposition in nitrogen atmosphere of several adducts with pyridine or substituted pyridines of VO (dbm) 2 , B, where dbm=dibenzoylmethane and B=pyridine (Py), 3-methylpyridine (3-MP), 4-methylpyridine (4-MP), 3-5-dimethylpyridine (3,5-DMP), 3-aminopyridine (3-AP) and 4-aminopyridine (4-AP)