Publications by authors named "Rafael Ortiz Alvarado"

Background: A family of 4-benzo[][1,3]oxazines were obtained from a group of -(2-alkynyl)aryl benzamides precursors via gold(I) catalysed chemoselective 6--dig C-O cyclization.

Method: The precursors and oxazines obtained were studied in breast cancer cell lines MCF-7, CAMA-1, HCC1954 and SKBR-3 with differential biological activity showing various degrees of inhibition with a notable effect for those that had an aryl substituted at C-2 of the molecules. 4-benzo[][1,3]oxazines showed an IC rating from 0.

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Mucormycosis is a lethal and difficult-to-treat fungal infection caused by fungi of the order Mucorales. Mucor lusitanicus, a member of Mucorales, is commonly used as a model to understand disease pathogenesis. However, transcriptional control of hyphal growth and virulence in Mucorales is poorly understood.

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Metformin is the most widely known anti-hyperglycemic, officially acquired by the USA government in 1995 and in 2001 it became the most prescribed treatment for type II diabetes. But how did it become the must-use drug for this disease in such a short period of time? it all started with traditional medicine, by using a plant known as "goat's rue" for the reduction of blood glucose levels. Its use arose in 1918 and evolved to the metformin synthesis in laboratories a couple of years later, using very rudimentary methods which involved melting and strong heating.

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Dimorphic species of , which are cosmopolitan fungi belonging to subphylum Mucoromycotina, are metabolically versatile. Some species of are sources of biotechnological products, such as biodiesel from and expression of heterologous proteins from . Furthermore, has been described as a model for understanding mucormycosis infections.

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Mucormycosis is a fungal infection caused by Mucorales, with a high mortality rate. However, only a few virulence factors have been described in these organisms. This study showed that deletion of rfs, which encodes the enzyme for the biosynthesis of rhizoferrin, a siderophore, in Mucor lusitanicus, led to a lower virulence in diabetic mice and nematodes.

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Iodine(III) reagents have attracted chemical relvance in organic synthesis by their use as safe, non-toxic, green and easy to handle reagents in different transformations. These characteristics make them important alternatives to procedures involving hazardous and harsh reaction conditions. Their versatility as oxidants has been exploited in the functionalization of different aromatic cores, which allow the introduction of several groups.

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The first gold(I)-catalyzed cycloisomerization procedure applied to the synthesis of substituted 4-benzo[][1,3]oxazines has been developed starting from -(2-alkynyl)aryl benzamides. The chemoselective oxygen cyclization via the 6--dig pathway yielded the observed heterocycles in modest to good chemical yields under very mild reaction conditions. The obtained oxazines were assayed on the breast cancer (BC)-derived cell lines MCF-7 and HCC1954 with differential biological activity.

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Zygomycetes are ubiquitous saprophytes in natural environments which transform organic matter. Some zygomycetes of gender Mucor have attracted interest in health sector. Due to its ability as opportunistic microorganisms infecting immuno-compromised people and to the few available pharmacological treatments, the mucormycosis is receiving worldwide attention.

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Unlabelled: is a fungus that produces diverse spores throughout its life cycle. The sporangiospores, which are the most well-studied spores in this fungus, are asexual spores produced during aerial mycelial development. has the potential to be used in diverse biotechnological applications.

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Abstract: This study investigated the presence of nontuberculous mycobacteria (NTM) for the first time in two types of unpasteurized fresh cheese produced in the state of Michoacan, Mexico. We tested for this pathogen, along with the others, to broaden the study of microbiological quality in 60 samples of cheese, 30 fresh and 30 Adobera, which were collected from six artisanal cheese factories (ACFs). The hygienic conditions of these establishments and the practices of cheese manufacture were generally poor.

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The chemoselective reaction of the - followed by the centered naphthyl radicals with the more electron-deficient hypervalent bond of the diaryliodonium(III) salts is described. This discovered reactivity constitutes a new activation mode of the diaryliodonium(III) salts which enabled a one-pot doubly arylation of naphthols through the sequential - /O- bond formation. The naphthyl radicals were generated in the reaction by the tetramethylpiperidinyl radical (TMP·) which resulted from the homolytic fragmentation of the precursor TMPO.

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Mucor circinelloides, a dimorphic opportunistic pathogen, expresses three heterotrimeric G-protein beta subunits (Gpb1, Gpb2 and Gpb3). The Gpb1-encoding gene is up-regulated during mycelial growth compared with that in the spore or yeast stage. gpb1 deletion mutation analysis revealed its relevance for an adequate development during the dimorphic transition and for hyphal growth under low oxygen concentrations.

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Mucor circinelloides is one of the causal agents of mucormycosis, an emerging and high mortality rate fungal infection produced by asexual spores (sporangiospores) of fungi that belong to the order Mucorales. M. circinelloides has served as a model genetic system to understand the virulence mechanism of this infection.

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The fungus undergoes yeast-mold dimorphism, a developmental process associated with its capability as a human opportunistic pathogen. Dimorphism is strongly influenced by carbon metabolism, and hence the type of metabolism likely affects fungus virulence. We investigated the role of ethanol metabolism in virulence.

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Mucor circinelloides is an opportunistic human pathogen that is used to study mucormycosis, a rare but lethal infection in susceptible immunosuppressed patients. However, the virulence characteristics of this pathogen have not been fully elucidated. In this study, sporangiospores (spores) produced on YPG medium supplemented with native blood serum increased the virulence of M.

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Objectives: This study investigated the presence of the crpP gene, which encodes an enzymatic mechanism of antibiotic phosphorylation that decreases ciprofloxacin susceptibility, in ESBL-producing clinical isolates and its effect in transconjugants.

Methods: A collection of 77 ESBL-producing clinical isolates of Enterobacteriaceae and 68 ESBL-producing transconjugants that had acquired plasmids from clinical isolates from hospitals in Mexico obtained from 1988 to 2012 was employed. The crpP homologue genes were identified by dot-blot and PCR assays; five of them were sequenced and an in silico analysis was conducted.

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A catalytic, practical and high-yielding procedure for the synthesis of indenes by direct Csp3-H activation under gold(i) catalysis was developed. The scope of the protocol was determined by synthesizing some electron-neutral, electron-poor as well as electron-rich derivatives including the dibenzofurane and carbazole heterocycles. The mechanism of this reaction was elucidated by theoretical calculations using a ONIOM(M08-HX/mixed-basis:PM6) hybrid scheme.

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A practical, concise and straightforward total synthesis of kealiiquinone 1, a naphtho[2,3-]imidazole alkaloid obtained from the Micronesian marine sponge sp. was accomplished. The squaric acid chemistry to construct the 1,4-quinoid ring and the regioselective -methylation through a benzo[][1,2,5]selenadiazolium heterocycle are the key features in this report.

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Mucor circinelloides is a dimorphic fungus used to study cell differentiation that has emerged as a model to characterize mucormycosis. In this work, we identified four ADP-ribosylation factor (Arf)-encoding genes (arf1-arf4) and study their role in the morphogenesis and virulence. Arfs are key regulators of the vesicular trafficking process and are associated with both growth and virulence in fungi.

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Gustatory papillae and associated taste buds receive and process chemical information from the environment. In mammals, their development takes place during the late phase of embryogenesis. However, the cellular factors that regulate the differentiation of taste papillae remain largely unknown.

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