Ezequiel Viveros- Valdez

Autonomous University of Nuevo León | UANL · Facultad de Ciencias Biológicas

Tuberculosis (TB) remains a major health problem worldwide, and the emergence of multi-resistant strains to first-line drugs has become the biggest obstacle to its treatment. On the other hand, the incidence of non-tuberculous mycobacteria (NTM) in humans has increased remarkably in recent years. The search for new and better treatments against myc...

Breast cancer is one of the main causes of death worldwide. Lately, there is great interest in developing methods that assess individual sensitivity and/or resistance of tumors to antineoplastics to provide personalized therapy for patients. In this study we used organotypic culture of human breast tumor slices to predict the experimental effect of...

The fruit of the Mexican madroño (Arbutus arizonica) has been consumed since pre-Columbian times by North American tribes and native groups in Mexico. Despite this, reports on its chemical composition and biological activity are limited. This work aims to determine the antioxidant, antiproliferative, and digestive enzyme inhibition activities of th...

Background Despite advances in screening and therapy, breast cancer (BC) remains the predominant cancer in women globally. Dysregulation of microRNAs (miRNAs) is pivotal in carcinogenesis across various cancers, including BC. Evidence indicates that miR‐1307‐3p is upregulated in BC tumors, yet its target genes are not fully elucidated. This study a...

Background/Objectives: In this study, the efficacy of benzo[h]chromene derivatives as antiprotozoal and antimycobacterial agents was explored. Methods: A total of twenty compounds, including benzo[h]chromene alkyl diesters and benzo[h]chromene-triazole derivatives, were synthesized and tested against Trypanosoma cruzi, Leishmania braziliensis, L. i...

Formaldehyde (FA) is an oxidative stress inducer and a known carcinogen. Hedeoma drummondii has been shown to have potential as a chemopreventive agent. The aim of this study was to assess the protective effect of H. drummondii on FA-induced genotoxic damage, sperm quality parameters, and histological changes of the testis. The male Wistar rats use...

Among neglected tropical diseases, leishmaniasis is one of the leading causes, not only of deaths but also of disability-adjusted life years. This disease, caused by protozoan parasites of the genus Leishmania, triggers different clinical manifestations, with cutaneous, mucocutaneous, and visceral forms. As existing treatments for this parasitosis...

Helicobacter pylori es una bacteria Gram negativa, con alta prevalencia a nivel mundial, la infección causa úlceras gástricas, duodenales y cáncer, se considera uno de los principales problemas de salud pública en México. El trabajo evalúa in vitro la actividad antioxidante, tóxica, antibacteriana y la capacidad de inhibir la biopelícula formada po...

Plants have been used to treat diseases since ancient times, but their active principles are regularly degraded in physiological conditions, such as that which occurs in the gastrointestinal tract. Therefore, the pharmaceutical industry focuses on designing new phytopharmaceutical forms to ensure that the active principle reaches the site of action...

Ungurahui, or Patawa, fruits are a popular fruit and medicinal food used in the Amazon. Here, we have studied nine natural populations of ungurahui from the Peruvian Amazon regarding their nutritional and biological activities, including metal composition, proximal analyses, cytotoxic, antioxidant and cholinesterase inhibition activities. Twenty-fo...

Seven medicinal plants from Chiapas, Mexico, used by Native Americans were analyzed, aiming to improve the understanding of their medicinal properties through the evaluation of various biological activities, i.e., bactericidal, antioxidant, α-glucosidase inhibition, and toxicity, to provide a scientific basis for the management of infectious and hy...

Los productos naturales juegan un papel relevante como fuente de ingredientes biológicamente activos con importancia cosmética y dermatológica. En los últimos años, los cosméticos basados en productos naturales han ganado una gran cantidad de atención no solo por parte de los investigadores sino también del público debido a la creencia general de q...

Ehretia tinifolia Linnaeus (Boraginacea) and Sideroxylon lanuginosum Michaux (Sapotaceae) are wild fruits consumed in North America and are appreciated for their pleasant flavor and sweet taste. However, details regarding their composition and biological properties in the available literature are scarce. This study reports the phenolic composition,...

This book provides a broad, well-structured review of strawberries and their cultivation under current environmental conditions. Methods of strawberry cultivation have undergone many improvements, and this book covers aspects from plant propagation, architecture, genetic resources, breeding, abiotic stresses and climate change to evolving diseases...

Background Multidrug-resistant infections due to Mycobacterium abscessus often require complex and prolonged regimens for treatment. Here, we report the evaluation of a new ex vivo antimicrobial susceptibility testing model using organotypic cultures of murine precision-cut lung slices, an experimental model in which metabolic activity, and all the...

A new library of twenty triazole-lapachol and nor-lapachol derivatives was synthesized. The compounds were evaluated against the epimastigotes form of Trypanosoma cruzi and promastigotes of Leishmania braziliensis and L. infantum. The cytotoxicity of the compounds was determined on murine fibroblasts and used to assess the selectivity index. The in...

Marine environments represent a great opportunity for the discovery of compounds with a wide spectrum of bioactive properties. Due to their large variety and functions derived from natural selection, marine natural products may allow the identification of novel drugs based not only on newly discovered bioactive metabolites but also on already known...

Marine environments represent a great opportunity for the discovery of compounds with a wide spectrum of bioactive properties. Due to the privileged conditions of natural selection, marine natural products are subject to overcome the pressure put on identify novel drugs; not only in the case of newly discovered bioactive metabolites, but also in th...

Aromatic plants have been widely used in Latin America for therapeutic and culinary purposes; various studies have shown the beneficial effect they have in the treatment of re-spiratory diseases, for which reason this work analyzes the potential of some aromatic plants used in the region for the treatment of the new severe acute respiratory syndrom...

Objectives: Precision-cut tissue slices are considered an organotypic 3D model widely used in biomedical research. The comet assay is an important screening test for early genotoxicity risk assessment that is mainly applied on in vitro models. The aim of the present study was to provide a 3D organ system for determination of genotoxicity using a m...

Macroalgae represent an important source of bioactive compounds with a wide range of biotechnological applications. Overall, the discovery of effective cytotoxic compounds with pharmaceutical potential is a significant challenge, mostly because they are scarce in nature or their total synthesis is not efficient, while the bioprospecting models curr...

Focused on our interest to develop novel antiparasistic agents, the present study was aimed to evaluate the biological activity of an extract of Laurencia johnstonii collected in Baja California Sur, Mexico, against an Acantamoeba castellanii Neff strain. Bioassay-guided fractionation allowed us to identify the amoebicidal diastereoisomers α-bromoc...

Breast cancer is the most common cancer type diagnosed in women, it represents a critical public health problem worldwide, with 1,671,149 estimated new cases and nearly 571,000 related deaths. Research on breast cancer has mainly been conducted using two-dimensional (2D) cell cultures and animal models. The usefulness of these models is reflected i...

Background and Objective: Marine environment represents countless and diverse resource for new drugs to combat major diseases. Extracts from four Laurencia species (L. johnstonii, L. pacifica, L. gardneri and L. papillosa) from Baja California Sur, México were evaluated for their antioxidant, antibacterial and cytotoxic activity. Methodology: The a...

Background and Objective: Invertebrates comprises more than fifty percent of marine animals. Among them, sponges are the most prolific source of bioactive compounds. Suberites aurantiacus (S. aurantiacus) is an abundant sponge in Mexican Pacific, which has been scarcely studied, for this reason authors screened it for its bioactivities. The current...

We sought to evaluate the hypolipidemic activity of extracts of Bidens odorata and Brickellia eupatorioides using a model of hyperlipidemia induced in rats by Triton WR-1339 (300mg/kg intraperitoneally). The rats were divided into 5 groups of 3 rats each: normal control group, hyperlipidemic control group, hyperlipidemic with 20 mg/kg atorvastatin,...

Formaldehyde (FA) interacts with biological molecules such as DNA and it induces DNA-protein cross-links (DPCs), oxidative stress, reactive oxygen species (ROS), methylation, chromosomal damage, fragmentation, and adducts of DNA, which are considered the most important genotoxic effects caused by exposure to FA. The purpose of this study was to eva...

Photodynamic therapy is a promising alternative for cancer treatment of solid tumors through generation of reactive oxygen species mediated by light-activated photosensitizing agents. One of the most promising types of photosensitizers is tetrapyrrolic macrocyclic compounds, such as meso-substituted porphyrins. In the present study, the synthesis o...

This study describes the total phenolic and flavonoid content as well as cytotoxic, alpha-glucosidase inhibition and antiradical/antioxidant potential of extracts obtained from the edible fruits of Cordia boissieri, which is widely distributed throughout northeastern Mexico. Phenolic and flavonoid content were evaluated by means of the Folin-Ciocal...

Formaldehyde (FA) is an environmental xenobiotic, which is genotoxic and carcinogenic to humans and animals; it induces DNA damage, mutations, and clastogenicity during critical cytogenetic events. FA-mediated oxidative stress is an important mechanism that has been associated with the induction of cytotoxic and genotoxic damage. Therefore, the obj...

The aims of this research were to examine the antibacterial, cytotoxic and antiradical/antioxidant activities of the organic extracts obtained from the leaves of the medicinal plant Morus celtidifolia (Family: Moraceae). To evaluate its antimicrobial properties, M. celtidifolia was tested against the bacteria of medical importance: Bacillus subtili...

Breast cancer is the leading cause of death in women worldwide. The search for novel compounds with antitumor activity, with less adverse effects and higher efficacy, and the development of methods to evaluate their toxicity is an area of intense research. In this study we implemented the preparation and culture of breast tumor explants, which were...

The aerial parts of the Lamiaceae Hedeoma drummondii (Benth.) are used in Mexico to prepare a herbal tea and by North American Amerindians as a spice. The methanolic extract of the aerial parts exhibited a strong antioxidant effect measured by the scavenging of the free diphenyl picrylhydrazyl (DPPH) radical. Assay-guided fractionation of the crude...

The antimicrobial and cytotoxic activities of organic extracts obtained from roots of the medicinal plant Jatropha dioica (Euphorbiaceae) were investigated. In order to evaluate their antimicrobial activity, the organic extracts were tested against clinical isolates of the human pathogens Bacillus cereus, Escherichia coli, Salmonella typhi, Staphyl...

Traditional medicine has strong roots in the Mexican population, particularly in areas where the diversity of species of plants and ethnic groups is higher. Such is the case of the southern Mexican state of Chiapas, home to one of the largest indigenous populations in the country. The primary objective of this work is to summarize information regar...

High speed centrifugal countercurrent chromatography (HSCCC) was successfully applied to preparative isolation of the main polar phenolics from the Peruvian Caricaceae Vasconcellea quercifolia A. St.-Hil. High-performance liquid chromatography with diode array (HPLC-DAD) and electrospray ionisation mass spectrometric detection (ESI-MS) was used to...

Precision-cut liver slices (PCLS) are mainly used to evaluate hepatotoxicity and metabolism of chemicals, as well as to study mechanisms of liver damage and repair. However, recently they have been used as a system to study amoebic infections. The aim of this study was to validate this model as an alternative for experimental amoebic liver absess (...

Hexane, acetone and methanol extracts obtained from Psidium guajava leaves were studied for their antifungal properties against Trichophyton rubrum, Trichophyton tonsurans, Sporotrix schenckii, Microsporum canis, Cryptococcus neoformans, Candida parapsilosis,and Candida albicans by using the agar disk diffusion technique. Compared to control, hexan...

"Pichi" or "pichi romero" (Fabiana imbricata R. et. P., Solanaceae) is a Chilean plant used as a tea in the Andean regions of Chile and Argentina. A very simple and direct method was developed for the qualitative analysis of polyphenols in the tea by high-performance liquid chromatography (HPLC) with diode array detection and electrospray ionizatio...

Hedeoma drummondii is a medicinal plant with diverse properties; however, validations of its medicinal uses are scarce. To evaluate its antimicrobial properties H. drummondii, was tested against opportunistic pathogens of medical importance. Antimicrobial tests were performed by the microdilution method in order to determine the Minimal Inhibitory...

Hedeoma drummondii (poleo) has been used by Mexicans to prepare a tea for its pleasant taste. The methanolic extract, polar fractions, and major antioxidant compounds of the Mexican herbal tea obtained from aerial parts of H. drummondii ("poleo") showed antiproliferative effects against the cancer cell lines MCF-7 (human breast) and HeLa (human cer...

The antioxidant activity of methanol extract of Lophocereus schottii was determined with three different tests: 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging; trolox equivalent antioxidant capacity (TEAC); and ferric reducing antioxidant power (FRAP). The extract showed significant activities in all antioxidant assays, in DPPH radical sca...