Universidad Veracruzana
  • Xalapa de Enríquez, Estado de Veracruz-Llave, Mexico
Recent publications
Objective Environmental enrichment is used to treat social, communication, and behavioral deficits and is known to modify the expression of synaptic receptors. We compared the effects of environmental enrichment in the expression of glutamate and endocannabinoid receptors, which are widely expressed in the cerebellar cortex. These two receptors interact to regulate neuronal function and their dysregulation is associated with behavioral changes. We used BTBR + Itpr3tf/J mice, a strain that models behavioral disorders, and C57BL/6 mice for comparison. We studied the effects of genetic background, sex, environmental conditions, and layer of the cerebellar cortex on the expression of each receptor. Results The influence of genetic background and environmental enrichment had the same pattern on glutamate and endocannabinoid receptors in males. In contrast, in females, the effect of environmental enrichment and genetic background were different than the ones obtained for males and were also different between the glutamate and endocannabinoid receptors. Furthermore, an analysis of both receptors from tissue obtained from the same animals show that their expression is correlated in males, but not in females. Our results suggest that environmental enrichment has a receptor dependent and sexual dimorphic effect on the molecular expression of different receptors in the cerebellar cortex.
The application of metal compounds in the medical field dates back to the XVI century with some isolated reports about the therapeutic importance of metals and their compounds in the treatment of various diseases, including cancer. Nowadays, the number of commonly prescribed metal-containing compounds is very broad and includes antimony (antiprotozoal), bismuth (antiulcer), iron (antimalarial), gold (antiarthritic), silver (antimicrobial), platinum (anticancer), and vanadium (antidiabetic), among others. Most biological molecules, such as DNA or proteins, are rich in electron density, while metal ions lack electrons. For that reason, we can observe a marked trend in which metal ions interact with various molecules of biological interest. Furthermore, metal ions also have a great affinity for various tiny molecules, such as molecular oxygen, which are essential to life. During the last sixty years, several classes of new metal derivatives, mainly organometallic and coordination compounds have been intensively investigated as possible anticancer and/or antitumour agents based on a great variety of metals, mainly from the d-block. Therefore, we previously reported a thorough bibliographic review of the cytotoxic and/or antiproliferative activity of the coordination compounds of the first transition series that contained benzimidazole ligands in their composition and structure https://doi.org/10.1016/j.ccr.2021.213930. In the same sense, in this work we expand our analysis to include the metals of the second and third transition series, hoping that this document will help in the choice of the appropriate ligands and metals for the design of new, more efficient, and selective metallodrugs. The main findings found in this review showed that the factors that we must consider in the design of coordination complexes with chemotherapeutic properties are: solubility, molecular structure and geometry, the global charge of the complex, the appropriate choice of the benzimidazole ligand considering the substituents or functional groups in its structure as well as the chirality conferred by its precursors; the appropriate choice of the metal centre considering its atomic radius, electronic configuration and oxidation state, it is even important to consider the use of co-ligands with guaranteed biological activity. These and other aspects related to the structure and activity of the compounds will be analysed below.
Environmental heterogeneity is expected to increase the richness and diversity of species. The aim of this study is to identify environmental elements that influence the richness and diversity of small, medium and large species of mammals. For the sampling of mammals, camera and Sherman traps were used at 18 sampling stations. For vegetation sampling, eight large-scale explanatory variables were selected in a 1000 m² plot at each station. The diversity (H’) of habitats (heterogeneity) and species were measured using the Shannon–Wiener diversity index. To relate the heterogeneity and environmental variables with species richness for small, medium and large mammals, a generalised linear model (GLM) was used while considering the Poisson probability distribution. A multiple linear regression model was used for data with normal distributions. The results suggested that environmental elements could favour rodent richness but may have a negative effect on community evenness and some environmental variables that are related to the diversity of rodent species and the species richness of medium and large mammals. It was concluded that the relationship between environmental heterogeneity and mammal richness is complex and that the response to the biotic elements of the landscape is diverse and different for each species.
Communicative complexity relates to social complexity, as individuals in more complex social systems either use more signals or more complex signals than individuals living in less complex ones. Taking the individual group member's perspective, here we examine communicative complexity in relation to social complexity, which arises from two components of social systems: social structure and social organization. We review the concepts of social relationships and social complexity and evaluate their implications for communicative and cognitive complexity using examples from primate species. We focus on spider monkeys ( Ateles geoffroyi ), as their social organization is characterized by flexibility in grouping dynamics and they use a variety of communicative signals. We conclude that no simple relationship exists among social complexity, communicative complexity and cognitive complexity, with social complexity not necessarily implying cognitive complexity, and communicative and cognitive complexity being independently linked to social complexity. To better understand the commonly implied link between social complexity and cognitive complexity it is crucial to recognize the complementary role of communicative complexity. A more elaborated communicative toolkit provides the needed flexibility to deal with dynamic and multifaceted social relationships and high variation in fission–fusion dynamics. This article is part of the theme issue ‘Cognition, communication and social bonds in primates’.
The ‘social complexity hypothesis' posits that complex social systems (which entail high uncertainty) require complex communicative systems (with high vocal flexibility). In species with fission–fusion dynamics, where the fluid composition of temporary subgroups increases the uncertainty with which group members must manage their social relationships, vocal communication must be particularly flexible. This study assessed whether contact call rates vary with caller and audience characteristics in free-living spider monkeys, as well as with fission and fusion events. Adult females and immature individuals called more when in small audience settings, while audience size did not influence adult males. Adults called more when in the presence of the opposite sex, whereas immatures vocalized more in subgroups composed only by females. Females also called more when with their mature sons. We found higher call rates in periods during which fission and fusion events took place than in periods with more stable compositions and when the composition after a fission or fusion event changed from one sex to two sexes. A flexible use of contact calls allows individuals to identify themselves when they join others, particularly if they are members of the opposite sex. This socio-spatial cohesion function reduces the uncertainty about subgroup composition. This article is part of the theme issue ‘Cognition, communication and social bonds in primates’.
The main objective of this work is to understand if a blind user has a good experience when using a support system when moving from point A to point B. To check this, the facilitators performed some User eXperience (UX) tests to analyze how the user interacts with the device. Specifically, tests were made with the modified methods “Thinking Aloud,” “Hedonic/Utility Scale” (HED/UT Scale) and “Positive and Negative Affect Scale.” The study sample included 5 blind participants, aged between 36 and 46 years old, of both genders, with a heterogeneous level of education and technology experience. The instruments used included the following: pretest, post-test, task evaluations, participant observation, and recording of both audio and video. Based on the results, users find the system challenging to use; therefore, applying the method allows developers and analysts to see how, where, and when the system fails to make the relevant improvements. Finally, we should mention that applying these modified methods allows for better target users’ feedback.
Most primate taxa are threatened by extinction and their populations are decreasing. The persistence of primates is thus conditional on conservation actions aimed at protecting them and their habitat. Here, we focus on the conservation of mantled howler monkeys (Alouatta palliata) in the Los Tuxtlas Biosphere Reserve, Mexico. Following the creation of the reserve in 1998, habitat availability and howler monkey abundance increased, suggesting that progress was being made in terms of the conservation of this species. Recent events, however, suggest otherwise, as mantled howler monkey habitat within the biosphere reserve is being disturbed by mining operations endorsed by the Mexican government. We report this case to raise awareness about the challenges for primate and habitat conservation in protected areas.
Abstract: In this work, electrochemical monitoring of stress corrosion cracking (SCC) behavior of a X70 steel in acidic synthetic soil solution during the slow strain rate test (SSRT) was performed by electrochemical noise (EN) using the conventional arrangement of symmetrical electrodes and electrochemical emission spectroscopy (EES) using the asymmetrical arrangement replacing the second working electrode for a platinum micro-cathode. The statistical method, fast Fourier transform, and discrete wavelet transform were used for analyzing the potential and current signals recorded by both arrangements. The results showed that EN arrangement was more effective to detect the crack initiation at a point close to yield strength despite stress-induced asymmetry in one of the electrodes. For the EES arrangement, the micro-cathode had a strong influence on the electrochemical noise of the current and potential under stress conditions. From the transient features, statistical parameters, and wavelet analysis, a discontinuous transgranular SCC mechanism was found. The resistance values obtained by EN measurements had better correlation with the electrochemical impedance spectroscopy results (EIS) than EES measurements.
Rhipicephalus ( Boophilus ) microplus tick infestation is a major problem for cattle industry in tropical and subtropical regions. Chemical products are commonly applied to control it; however, their indiscriminate use has resulted in the appearance of resistant lineages. Plants have been used as an alternative to conventional acaricidal drugs. Recently, we demonstrated the higher acaricidal activity of hidroethanolyc extract of Randia aculeata seed (EHRA) against R. microplus under laboratory conditions. The utility of EHRA seed as acaricidal need to be determined under field conditions. For this reason, the aim of this study was (a) evaluate the efficacy of the EHRA against R. microplus by sprayed on naturally infested calves under field conditions (b) determine the effect of the EHRA seed on AChE activity in larvae R. microplus and (c) evaluate the stability of total phenolic compounds in EHRA after exposure to heating, UV irradiation and storage. Fourty-five male calves were divided in three groups and doused by spray G1: water, G2: EHRA 20% and G3: coumaphos 0.3%. AChE activity on R. microplus larvae was determined by a colorimetric assay. Total phenolic content was determined using the Folin-Ciocalteau method after to exposure of EHRA to heat, UV light and storage under sunlight and dark. Significantly fewer number of ticks were observed after 24 h on the treated group compared to control group ( p < 0.001). EHRA significantly inhibited in vitro acetylcholinesterase activity in R. microplus larvae at all tested concentrations ( p < 0.01). Heat, UV light and storage time under sunlight resulted in a significant decrease ( p < 0.05) in total phenolic content. Our results contributed new data for the elucidation of the mechanisms of EHRA acaricide action and to further evaluate the use as a new alternative control agent against R. microplus under in vivo conditions
Depressive disorders are among the most disabling diseases experienced around the world, and their incidence has significantly increased over the last few decades due to multiple environmental, social, and biological factors. The search for new pharmacological alternatives to treat depression is a global priority. In preclinical research, molecules obtained from plants, such as flavonoids, have shown promising antidepressant-like properties through several mechanisms of action that have not been fully elucidated, including crossing of the blood brain barrier (BBB). This review will focus on discussing the main findings related to the participation of the serotonergic system and brain-derived neurotrophic factor (BDNF) on the antidepressant-like effect of some flavonoids reported by behavioral, neurochemical, and molecular studies. In this sense, evidence shows that depressive individuals have low levels of serotonin and BDNF, while flavonoids can reverse it. Finally, the elucidation of the mechanism used by flavonoids to modulate serotonin and BDNF will contribute to our understanding of the neurobiological bases underlying the antidepressant-like effects produced by these natural compounds.
Maintaining floristic diversity in recognized biodiversity hotspots is a priority for ecosystem conservation. However, different taxonomical treatments often lead to over or underestimation of floristic diversity in species-rich groups, in particular in Tropical regions as Mesoamerica where floristic surveys are less detailed. Also, understanding the effects of climate changes on species distribution is an emerging question of conservation biology and ecological studies. Here, we used the species-rich genus Piper (Piperaceae) in Veracruz, as a model system to compare reported and actual species richness and to model their occurrence under a climate change scenario. We compared morphological characters of specimens preserved in three of the main Mexican herbaria and then applied new taxonomical treatments. We also used environmental niche models (ENMs) as implemented in Maxent to detect the effects of climate changes on species with different levels of habitat specificity and with specialized biotic interactions. We found that from a total of 108 Piper species reported in Veracruz, 80 were consistent to the new taxonomical treatments due to synonymy or misidentification. ENMs showed that the main determinants of Piper distribution are linked to temperature and precipitations depending on the species. Therefore, different species are likely to respond differently to climate changes. As expected, species with higher habitat specificity and species exhibiting specialized mutualisms are more likely to experience niche contractions. This study shows the importance of reconsidering species richness and of modelling species distribution including specialized ecological interactions as prerequisite for establishing conservation criteria.
In the aeronautical industry, Al-Cu alloys are used as a structural material in the manufacturing of commercial aircraft due to their high mechanical properties and low density. One of the main issues with these Al-Cu alloy systems is their low corrosion resistance in aggressive substances; as a result, Al-Cu alloys are electrochemically treated by anodizing processes to increase their corrosion resistance. Hard anodizing realized on AA2024 was performed in citric and sulfuric acid solutions for 60 min with constant stirring using current densities 3 and 4.5 A/dm2. After anodizing, a 60 min sealing procedure in water at 95 °C was performed. Scanning electron microscopy (SEM) and Vickers microhardness (HV) measurements were used to characterize the microstructure and mechanical properties of the hard anodizing material. Electrochemical corrosion was carried out using cyclic potentiodynamic polarization curves (CPP) and electrochemical impedance spectroscopy (EIS) in a 3.5 wt. % NaCl solution. The results indicate that the corrosion resistance of Al-Cu alloys in citric acid solutions with a current density 4.5 A/dm2 was the best, with corrosion current densities of 2 × 10−8 and 2 × 10−9 A/cm2. Citric acid-anodized samples had a higher corrosion resistance than un-anodized materials, making citric acid a viable alternative for fabricating hard-anodized Al-Cu alloys.
Background Even though various studies recognize the importance of the oral cavity to have general health, in multidisciplinary professional practice it is almost always excluded and on an individual basis, very commonly neglected. Oral diseases are preventable, still, they are highly prevalent. Although some studies consider oral health within integral health, currently, there is no model in which the mouth is integrated within other levels for the achievement of well-being. The objective of this article was to review the importance of oral health and its connection with well-being and, based on these findings, propose a complex and comprehensive perspective for approach and care.Methods The databases MEDLINE, PubMed, and Google Scholar were revised for randomized controlled trials and reviews that included search terms related to oral health and its relationship with the general health in its different levels (physical, psychological, social and environmental).ResultsThe review shows that oral health is critical, as the teeth and mouth are not only an integral part of the body, but also, they also support and enable essential human functions. That is, oral health has a multidimensional nature, as it includes the physical, psychological, social, and environmental domains that are essential for overall health and well-being. Likewise, the mouth is the psychological seat of the first physiological needs and emotional gratifications, with it we take a taste of the world around us. Thus, the mouth plays an important role in the feeling of unity and in the constitution of the self. Based on these results we propose an integrative model in which the mouth is the first step for well-being and from this integrative model we build a multidisciplinary approach which could be used in the clinical practice for the promotion of oral care and general health.Conclusion The effort on the part of oral health professionals is essential for people's well-being and must be integrated as part of health promotion. Dental treatments alone cannot solve this problem, it requires a comprehensive and approach in which the bio-psychological, behavioral, and socio-environmental determinants are included to face this global oral health challenge. That is, without a comprehensive and multidisciplinary approach to medical science that includes dental and oral health, our public policies cannot provide the best answers to health promotion, disease prevention, early detection, and treatment.
The COVID-19 pandemic negatively affected the progress in accessing essential Tuberculosis (TB) services and reducing the burden of TB disease, resulting in a decreased detection of new cases and increased deaths. Generating molecular diagnostic tests with faster results without losing reliability is considered a priority.
Considering that an accurate detection of infected mosquitos may directly avoid the propagation of mosquito-borne disease; in this paper, we propose a detection system of infected mosquitos by Dengue virus type II, that uses seven spectral feature measures, which are applied to the spectrogram estimated from wingbeat signal emitted by mosquito’s flight. To evaluate the proposed system, we construct our own dataset with 20 infected Aedes aegypti by Dengue and 20 healthy ones. Seven spectral analysis methods, such as Spectral Rolloff, Spectral Centroide, etc., are applied to the spectrogram obtained by using the Short Time Fourier Transform (STFT) to generate feature vectors with 15 elements. These are feed into common machine learning techniques, such as Support Vector Machine (SVM), K-Nearest Neighbor (KNN) and Logistic Regression to detect the infected mosquitos differentiating form the healthy ones. Evaluation results show that, the best detection accuracy (84.32%) is provided by the KNN with K=3.
The Mexican fruit fy (Anastrepha ludens, Loew, Diptera: Tephritidae) and the Mediterranean fruit fy (Ceratitis capitata, Wiedemann, Diptera: Tephritidae) are among the world's most damaging pests affecting fruits and vegetables. The Sterile Insect Technique (SIT), which consists in the mass-production, irradiation, and release of insects in affected areas is currently used for their control. The appropriate time for irradiation, one to two days before adult emergence, is determined through the color of the eyes, which varies according to the physiological age of pupae. Age is checked visually, which is subjective and depends on the technician's skill. Here, image proc�essing and Machine Learning techniques were implemented as a method to determine pupal development using eye color. First, Multi Template Matching (MTM) was used to correctly crop the eye section of pupae for 96.2% of images from A. ludens and 97.5% of images for C. capitata. Then, supervised Machine Learning algorithms were applied to the cropped images to classify the physiological age according to the color of the eyes. Algorithms based on Inception v1, correctly identifed the physiological age of maturity at 2 d before emergence, with a 75.0% accuracy for A. ludens and 83.16% for C. capitata, respectively. Supervised Machine Learning algorithms based on Neural Networks could be used as support in determining the physiological age of pupae from images, thus reducing human error and uncertainty in decisions as when to irradiate. The development of a user interface and an automatization process could be further developed, based on the data obtained on this study.
During 2020, producers of Hass avocado (Persea americana Mill.) in the central region of Veracruz State detected atypical damage associated with infestation by thrips. Larvae and adults were feeding on developing fruits, causing wounds in the epidermis, producing necrotic spots, and reducing commercial value. Insects were collected from affected fruits, mounted, and identified using specialized keys. Images of damage were obtained, and numbers of affected trees and fruits were quantified. Thrips specimens were identified as Pseudophilothrips perseae (Thysanoptera: Phlaeothripidae) with an incidence of 1.6% in the orchard examined. Damage by P. perseae in this work differed from that usually caused by other thrips species that feed and oviposit on tender tissues of avocado trees. We reported for the first time, damage caused by P. perseae in developing avocado fruits. More study is necessary to determine distribution and potential to increase in abundance and affect crop production.
Although it is known that the first case of cancer was recorded in ancient Egypt around 1600 BC, it was not until 1917 during the First World War and the development of mustard gas that chemotherapy against cancer became relevant; however, its properties were recognised until 1946 to later be used in patients. In this sense, the use of metallopharmaceuticals in cancer therapy was extensively explored until the 1960s with the discovery of cisplatin and its anticancer activity. From that date to the present, the search for more effective, more selective metallodrugs with fewer side effects has been an area of continuous exploration. Efforts have led to consider a wide variety of metals from the periodic table, mainly from the d ‐block, as well as a wide variety of organic ligands, preferably with guaranteed biological activity. In this sense, various research groups have found an ideal binder in Schiff bases, since their raw materials are easily accessible, their synthesis conditions are friendly and their denticity can be manipulated. Therefore, in this review, we have explored the anticancer and antitumor activity reported in the literature for coordination complexes of d ‐block metals coordinated with tridentate Schiff bases (O^N^O and O^N^N) derived from salicylaldehyde. For this work, we have used the main scientific databases CCDC® and Scifinder®.
This research reflects on the environmental problems that we are currently experiencing as a society and discusses education as an opportunity to solve them. Several frameworks of university digital competencies are identified and environmental care is highlighted as an important part of them, so the objective is to know the perceptions of university students in Mexico on digital competency and environmental protection and verify the following hypothesis: “currently there a is little development of environmental awareness and the relationship between the use of Information Technology (IT) as well as its environmental impact among university students”. For this purpose, a quantitative, non-experimental approach was used, specifically, a descriptive cross-sectional design using a Likert-type questionnaire was applied on 22 and 23 November 2021 to 135 students from two public universities belonging to four undergraduate programs in Mexico. The results indicate that most students are aware that the use of electronic devices for educational purposes has an impact on the environment and that, therefore, it is necessary to adopt effective measures and habits for an adequate and optimal use of digital environments.
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8,607 members
Juan Carlos Noa-Carrazana
  • Instituto de Biotecnología y Ecología Aplicada (INBIOTECA)
Laura Teresa Hernandez
  • Instituto de Neuroetología
Juventino Garcia
  • Instituto de Investigaciones Forestales
María Cristina Mac Swiney González
  • Centro de Investigaciones Tropicales
Roberto Zenteno-Cuevas
  • Instituto de Salud Pública
Lomas del Estadio S/N. Zona Universitaria, 91000, Xalapa de Enríquez, Estado de Veracruz-Llave, Mexico
Head of institution
Dra. Sara Deifilia Ladrón de Guevara González