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"Morales, A. J."
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Population genetic screening efficiently identifies carriers of autosomal dominant diseases
2020
Three inherited autosomal dominant conditions—
BRCA
-related hereditary breast and ovarian cancer (HBOC), Lynch syndrome (LS) and familial hypercholesterolemia (FH)—have been termed the Centers for Disease Control and Prevention Tier 1 (CDCT1) genetic conditions, for which early identification and intervention have a meaningful potential for clinical actionability and a positive impact on public health
1
. In typical medical practice, genetic testing for these conditions is based on personal or family history, ethnic background or other demographic characteristics
2
. In this study of a cohort of 26,906 participants in the Healthy Nevada Project (HNP), we first evaluated whether population screening could efficiently identify carriers of these genetic conditions and, second, we evaluated the impact of genetic risk on health outcomes for these participants. We found a 1.33% combined carrier rate for pathogenic and likely pathogenic (P/LP) genetic variants for HBOC, LS and FH. Of these carriers, 21.9% of participants had clinically relevant disease, among whom 70% had been diagnosed with relevant disease before age 65. Moreover, 90% of the risk carriers had not been previously identified, and less than 19.8% of these had documentation in their medical records of inherited genetic disease risk, including family history. In a direct follow-up survey with all carriers, only 25.2% of individuals reported a family history of relevant disease. Our experience with the HNP suggests that genetic screening in patients could identify at-risk carriers, who would not be otherwise identified in routine care.
Screening for a set of autosomal-dominant genetic conditions in a large, unselected cohort of individuals uncovers carriers who were missed by routine medical care, demonstrating the utility of broad genetic screening.
Journal Article
The importance of factorial design on the optimization of biosensor performance: immobilization of glucose oxidase as a case study
by
Escalona-Villalpando, Ricardo A
,
Huerta-Manzanilla, Eric L
,
Mendoza-Camargo, A. P
in
Biosensors
,
Data analysis
,
Design analysis
2024
Conventionally, the optimization of glucose biosensors is achieved by varying the concentrations of the individual reagents used to immobilize the enzyme. In this work, the effect and interaction between glucose oxidase enzyme (GOx), ferrocene methanol (Fc), and multi-walled carbon nanotubes (MWCNTs) at different concentrations were investigated by a design of experiments (DoE). For this analysis, a factorial design with three factors and two levels each was used with the software RStudio for statistical analysis. The data were obtained by electrochemical experiments on the immobilization of GOx-Fc/MWCNT at different concentrations. The results showed that the factorial DoE method was confirmed by the non-normality of the residuals and the outliers of the experiment. When examining the effects of the variables, analyzing the half-normal distribution and the effects and contrasts for GOx-Fc/MWCNT, the factors that showed the greatest influence on the electrochemical response were GOx, MWCNT, Fc, and MWCNT:Fc, and there is a high correlation between the factors GOx, MWCNT, Fc, and MWCNT:Fc, as shown by the analysis of homoscedasticity and multicollinearity. With these statistical analyses and experimental designs, it was possible to find the optimal conditions for different factors: 10 mM mL−1 GOx, 2 mg mL−1 Fc, and 15 mg mL−1 MWCNT show a greater amperometric response in the glucose oxidation. This work contributes to advancing enzyme immobilization strategies for glucose biosensor applications. Systematic investigation of DoE leads to optimized immobilization for GOx, enables better performance as a glucose biosensor, and allows the prediction of some outcomes.Schematic representation of the study of factors to optimize the performance of a glucose biosensor by design of experiments.
Journal Article
Thermal and Textural Properties of Organogels Developed by Candelilla Wax in Safflower Oil
by
Charó-Alonso, M
,
Alonzo-Macias, M
,
González-Chávez, M. M
in
alkanes
,
Biological and medical sciences
,
candelilla wax
2007
We investigated organogel formation in dispersions of CW in safflower oil (SFO). Candelilla wax (CW) has as its main component hentriacontane (78.9%), a n-alkane with self assembly properties in organic solvents (i.e., vegetable oils). Results showed that, independent of the cooling rate (i.e., 1 °C/min and 10 °C/min) and gel setting temperature (T set), the CW organogels observed a thermoreversible behavior. This was evaluated by the behavior of thermal parameters that characterized organogel formation (gelation temperature, T g; heat of gelation, ΔHg) and melting (melting temperature, T p; heat of melting, ΔHM) after two heating-cooling cycles. For a given CW concentration (i.e., 0.5, 1.0, and 3%), the magnitude of ΔHM and T p and the structural organization of the organogel, depended on the cooling rate, the thermodynamic drive force for gelation, and the annealing process occurring at high Tset (i.e., 25 °C). At T set of 25 °C the microplatelet units that formed the organogel aggregated as a function of storage time, a process that resulted in an increase in organogel hardness. In contrast, at T set of 5 °C annealing occurred in a limited extent, but gels had higher solid fat content and microplatelet units of a smaller size than the gels obtained at 25 °C. The result was a three-dimensional network with greater hardness than the one obtained at 25 °C. The 3% CW organogels showed no phase separation up to 3 months at room temperature, with textures of potential use by the food industry.
Journal Article
Global Situation of Bioremediation of Leachate-Contaminated Soils by Treatment with Microorganisms: A Systematic Review
by
Mendoza-Burguete, Yesenia
,
Ledesma-García, J.
,
Ramos-López, M. A.
in
Bacteria
,
Biodegradation
,
Bioremediation
2023
This systematic review presents the current state of research in the last five years on contaminants in soils, especially in leachates from solid waste landfills, with emphasis on biological remediation. In this work, the pollutants that can be treated by microorganisms and the results obtained worldwide were studied. All the data obtained were compiled, integrated, and analyzed by soil type, pollutant type, bacterial type, and the countries where these studies were carried out. This review provides reliable data on the contamination of soils worldwide, especially soils contaminated by leachate from municipal landfills. The extent of contamination, treatment objectives, site characteristics, cost, type of microorganisms to be used, and time must be considered when selecting a viable remediation strategy. The results of this study can help develop innovative and applicable methods for evaluating the overall contamination of soil with different contaminants and soil types. These findings can help develop innovative, applicable, and economically feasible methods for the sustainable management of contaminated soils, whether from landfill leachate or other soil types, to reduce or eliminate risk to the environment and human health, and to achieve greater greenery and functionality on the planet.
Journal Article
A preliminary study of cyclic voltammetry in glassy carbon electrode. Redox Behaviour of 2-Amino-4-phenylthiazoles
by
Rios-Acevedo, J. J.
,
Florez-Lopez, E.
,
Morales-Morales, J.A
in
Chemical reduction
,
Creasing
,
Electrochemical analysis
2018
In this work a voltammetric study of the reduction processes of five substituted 2-Amino-4-(4-X-phenyl) thiazoles (-X = -H, -OCH3, -CH3, -Cl, -NO2) in dimethylsulphoxido was performed. In the potential range considered (-2.0 to -2.9 V vs Ag+/AgCl), one signal (Ic) were detected, which was associated with the electrochemical reduction of the corresponding of the heterocycle compound. The voltammetric analysis at the reduction signal showed that when in-creasing the sweep speed (0.1 < v < 1.0 Vs-1), an oxidation signal associated with the Ic wave was not observed. The linear dependence of the peak current with respect to the root of the velocity of the Ic wave, showed that this was a process controlled by diffusion and showed an apparently irreversible behavior. Peak potential shifted to more negative values as the potential sweep speed was higher; this was indicative of irreversible behavior in this signal. The substitution changes influenced the electrochemical behavior, evidencing that a substituent, as in this case methoxy group compound -OCH3, causes a greater energetic demand for the reduction of the thiazole derivative it becomes evident in the most negative potential, with respect to the derivative without substituent -H. This was new evidence of the behavior electrochemical of 2-Amino-4-(4-X-phenyl) thiazoles derivates which had not been reported for these compounds.
Journal Article
Repeatability Assessment in Tunnel Fire Experiments
by
Morales Mere, J A
,
Madsen, D
,
Johansson, N
in
Boundary conditions
,
Reproducibility
,
Temperature profiles
2024
A medium-scale experimental setup located in Revinge, Sweden, is used to generate new repeated experimental datasets focussed on measuring a set of key variables, including time-temperature curves and temperature profiles. A total of 6 repeated fire tests were conducted and are here used to exemplify typical issues associated with repeatability, uncertainty and variability in tunnel fire experiments. A key aspect considered in this work is the smoke stratification among repeated experiments and how fire behaviour can be affected by boundary conditions. This work is important to facilitate future efforts to collect high-quality tunnel fire data including a quantitative assessment of the experimental uncertainty, data that will be useful for validation of tunnel fire models.
Journal Article
Electrochemical reduction processes on glassy carbon electrode of 2-Amino-4-phenylthiazoles
by
Salazar-Osorio, M
,
Florez López, E
,
Morales-Morales, J A
in
Chemical reduction
,
Electrochemical analysis
,
Electron transfer
2018
In this work the electrochemical reduction of the compounds 2-Amino-4-(4-R-phenyl)thiazoles (1a, R = -H and 1b, R = -NHCOCH3) was performed by cyclic voltammetry in dimethylsulfoxide (DMSO) + 0,1 M tetraethylammonium tetrafluoroborate (TEABF4) and tetrabutylammonium hexafluorophosphate (TBAPF6). Two reduction signal were observed, the Ic wave (EpIc = -2.52 V) and wave IIc (EpIIc = -2.77 V) due to an electron transfer of the electrogenerated product in the Ic wave. The change of substituent influences the electrochemical behaviour, showing that an electrodonating substituent causes a higher energy requirement for the reduction of 1b, which became evident in the more negative potential, with respect to 1a. Additionally, it was observed that the peak potential in the first reduction signal Ic wave shifted to more negative values as the potential sweep rate was higher and this was indicative of an irreversible behaviour. A larger salt such as TBAPF6 causes a decrease in the intensity of peak reduction currents, contrary to what was shown by a smaller salt such as TEABF4. Also for both compounds, the cathodic peak potential of wave Ic and IIc is influenced by the effect of the size of salt used. A smaller salt favoured the electrochemical reduction of both heterocyclic compounds.
Journal Article
Study of the electrochemical oxidation of 2-Thiazolamine and 2-Oxazolamine on a platinum wire as working electrode
by
Rios-Acevedo, J J
,
Villamarin, A F
,
Florez-López, E
in
Diffusion rate
,
Electrochemical oxidation
,
Electrodes
2018
The electrochemical oxidation of 2-aminothiazole (2AT) and 2-aminooxazole (2AO) was studied by means of the cyclic voltammetry technique (VC), on a Pt wire as working electrode. An anodic wide peak centred at 0.79V was observed and 0.98V (Ia wave) caused by the oxidation of the 2AT and 2AO compounds and the formation of cationic radicals on the clean surface of the electrode, respectively. During the studies of (VC) in a small range of exploration speeds, the oxidation signal increased with the increase in speed and moved to more positive potential values. This dependence of the potential with respect to the potential sweep speed indicated a controlled diffusion of the system of an irreversible nature. At T = 298K, from the electrochemical oxidation of 2 AT, a thin coating film with a light brown color was obtained on the surface of the Pt wire. However, in the electroxidation of 2 AO, that result was not evident. While the 2AT electroxidation product loses conductivity, in the case of the 2AO compound, the electrogenerated product on the surface of the platinum wire maintains the conductive properties.
Journal Article
Differences in moral reasoning among medical graduates, graduates with other degrees, and nonprofessional adults
by
Orozco-Morales, J. A.
,
Chapa-Koloffon, G.
,
Ávila-Hernández, A. V.
in
Academic degrees
,
Beliefs, opinions and attitudes
,
Cognitive Development
2022
Background
Reasoning and moral action are necessary to resolve day-to-day moral conflicts, and there are certain professions where a greater moral character is expected, e.g., medicine. Thus, it is desirable that medical students develop skills in this field. Some studies have evaluated the level of moral reasoning among medical students; however, there are no comparative studies involving other types of populations. Therefore, the objective of this study was to compare the moral reasoning among medical graduates with that of a group of young graduates with other degrees and of a group of nonprofessional adults.
Methods
An exploratory cross-sectional study was conducted. Pediatric residents and pediatric subspecialty residents at a pediatric hospital were invited to participate, forming the group of “medical graduates”. A group of young people from a social program and students with a master’s degree in a science from the same pediatric hospital were also invited to participate, comprising the group of “graduates with other degrees”. Finally, a group of beneficiaries of a family clinic was invited to participate, which we categorized as “nonprofessionals”. To evaluate the differences in moral reasoning between these 3 groups, we applied the Defining Issues Test (DIT), a moral reasoning questionnaire designed by James Rest using Kohlberg’s theory of moral development.
Results
The moral reasoning of 237 subjects—88 from the “medical graduates” group, 82 from the “graduates with other degrees” group and 67 from the “nonprofessionals” group— was evaluated. We found differences in the profiles of moral development of the groups. The profile of the “nonprofessionals” showed a very high predominance of subjects at the preconventional level, 70%, but only 4.5% at the postconventional level. Among the “medical graduates”, we observed 37.5% at the preconventional level and 34% at the postconventional level (X
2
p
< 0.001); this group had the highest percentage in this category. This large difference could be because the differences in the ages and socioeducational levels of nonprofessionals are much wider than those among medical graduates. However, significant differences were also found when the profiles of medical graduates were compared with those of graduates with other degrees, since the latter demonstrated 56% at the preconventional level and 18% at the postconventional level (X
2
test,
p
= 0.02).
Conclusions
Significant differences were found in moral reasoning among the groups that we evaluated. Among the group of medical graduates, there was a higher percentage of subjects at the postconventional level than among the group of graduates with other degrees and a much higher percentage than among the group of nonprofessionals. Our conclusions give the first evidence that studying medicine seems to influence the development of moral reasoning in its students. Therefore, we consider it relevant to develop educational strategies where the student is involved in simulated but realistic decision-making situations, where there are moral dilemmas to resolve from their early years of training.
Journal Article
Development of bioanode for versatile applications: microfuel cell system in the presence of alcohol and glucose
by
Escalona-Villalpando, R. A
,
Arriaga, L. G
,
Trejo-Arroyo, D. L
in
Adaptability
,
Alcohol
,
Alcohol dehydrogenase
2022
The purpose of this work is to develop a bioanode using the enzymes of glucose oxidase (GOx) and alcohol dehydrogenase (ADH) as catalysts to oxidised glucose and alcohol present in different beverages. The study was carried out using the covalent bonding method for both enzymes via the functionalization of carbon nanofibers for the formation of carboxyl groups that can form bonds with the amine groups of the enzyme, as well as using tetrabutylammonium bromide (TBAB) with Nafion. The optimum operation parameters of both enzymes (pH and temperature) were determined for the later evaluation in a microfluidic fuel cell. In addition, using the scanning electrochemical microscopy technique, a local study of enzymatic processes is used to demonstrate that the enzymes immobilized on the same electrode remain active. The evaluation of the microfluidic fuel cell was carried out using different solutions, 0.01 M glucose, 0.01 M ethanol and a mixture of 0.01 M glucose and 0.01 M ethanol, all in phosphate buffer solutions at pH 7, where it was possible to obtain a maximum performance of 5.07 ± 0.1 mW cm−2, and there was a significant increase in current density compared to non-composite solutions (glucose or ethanol). In addition, different alcoholic beverages were used to evaluate the versatility and adaptability of the bi-enzymatic anode electrode with the perspective use in Lab-on-a-Chip systems.
Journal Article