Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Over the last few years, great breakthroughs have been made in the study of the structure and regulation of the bacterial flagellum. Despite their diversity, all flagellar systems share a basal body, a hook, and a filament. The flagellar assembly is tiered and tightly regulated. The final step in the flagellar biogenesis is the filament assembly composed by flagellin subunits, the most abundant flagellar protein. The filament synthesis is metabolically expensive hence, is tightly regulated. In this review, we present the most relevant advances in the understanding of the regulatory mechanisms of flagellin expression at the transcriptional, posttranscriptional, and posttranslational level across the most representative bacterial groups.

The COVID-19 pandemic is a global public health problem that has revealed deficiencies and challenges in health systems worldwide. To date, four waves (each one driven by different viral variants and showing different behaviors) have affected Mexico. Here we describe the COVID-19 pandemic behavior in the population of Sinaloa, Mexico after four epidemic waves. Epidemiological data were obtained from public federal databases from March 2020 to February 2022, and genomes of SARS-CoV-2 variants of interest (VOI) and concern (VOC) in Sinaloa were downloaded from the GISAID database from January 2021 to May 2022. The relative risk (RR) of SARS-CoV-2 infection was calculated from public data. Sinaloa presented four epidemic waves from March 2020 to February 2022, and each wave was driven by different variants with different degrees of transmissibility and severity. Interestingly, the delta variant (which dominated the third wave) was probably the most severe, producing a large number of cases per day and high mortality rates, while the omicron variant (which dominated the fourth wave) produced the largest number of cases per day but decreased mortality rates. Most of the COVID-19 cases in Sinaloa occurred among people between 30 and 45 years old, and the average age of the deceased was above 60 years old in all waves. Older people showed higher risk of infection than infants and younger people; however, the relative risk (RR) for people older than 60 years old decreased in the third and fourth waves. Men older than 60 years old showed higher RR than women of the same age group. The COVID-19 pandemic has shown changing behaviors in time, mostly derived from different emerging viral variants and the immunization of the population. Overall, these results show that SARS-CoV-2 infections appear in timely waves, each one driven by different variants (and subvariants or sublineages), with different degrees of transmissibility and severity. The population should continue with preventive measures to avoid infection.

The maize crop is affected by the “army worm” Spodoptera frugiperda and the severity of the damage it causes to the plants negatively affects both their growth and yield. The objective of this study was to evaluate the effect of using different probiotics and agrochemicals for its control. The experiment was carried out in a randomized block design in a split plot arrangement with three replications. The large plots were the chemical products: Chlorpyrifos (Ch) and Emamectin benzoate (Eb) in doses of 0.625 and 0.150 L ha-1, respectively, more the control, and the small plots were the probiotics Bacillus thuringiensis (Bt) and Beauveria bassiana (Bb) in doses of 0.512 kg ha-1 and 0.750 L ha-1, respectively, more the control. The treatment with Be was positive due to the result of a lower percentage of infested plants (PIP) and a reduced severity of damage (SD) produced by S. frugiperda, in addition to an increase in both plant vigor and crop yield grain, with values of 24.6%, 4.5 and 6.8 ton ha-1, respectively. There was no statistical difference between the Bt and Bb probiotics in grain yield, but it was higher than that obtained in each of the probiotics compared to the control. The decrease in PIP and SD, due to the pest, were more evident in the first 75 days after sowing (DAS), and from this number up to 90 days, the vigor and growth of the plant showed higher rates of increase.

Ruminant livestock is considered one of the largest anthropogenic sources of methane gas. Methanogenesis is part of the digestive process of these animals and is mediated by the microorganisms present in their rumen, responsible not only for the loss of energy in the animal, which directly impacts the productivity of cattle, but also for the production of methane that contributes to the increase of the greenhouse effect. The functional characteristics of the rumen microbiome have not been well described because most of the microorganisms present are not cultivable under laboratory conditions, but can be studied using molecular techniques, such as metagenomics and metatranscriptomics. The objectives of this review article, in addition to compiling and disseminating information on the environmental impact of the livestock industry, are to describe some of the experimental and bioinformatic strategies used in the analysis of the ruminal microbiome from metagenomics and metatranscriptomics, to reduce emissions of methane by cattle.

In Mexico, a wide variety of fermented beverages have been produced since pre-Hispanic times, which are currently considered traditional and although their content has been scarcely investigated, there are studies that report their beneficial effects on consumer health due not only to the presence and microbial/probiotic action, but also to that of multiple compounds of biological importance. The objective of this review is to highlight the information available on four selected beverages, the probiotics present in them, their mechanism of action and their possible applications in human health; therefore, scientific information on probiotics was compiled, available in databases such as: Pubmed, Science Direct, Web of Science, SciELO, Redalyc, Dialnet, Springer and Google Scholar. In conclusion, more studies and clinical trials in humans are necessary to support its biomedical application in some pathologies that affect public health.

The development of sophisticated artificial intelligence algorithms and the massive availability of biomedical data have driven accelerated research to discover novel treatments using drugs previously developed and approved for other uses. This process is known as drug repositioning (DR), and it can be addressed by a branch of artificial intelligence (AI) known as machine learning (ML). Machine learning is based on a set of algorithms that, combined with well-established computational techniques in the field of drug discovery, have been able to infer new previously unknown pharmacological properties and relationships with high efficiency. Thus, new targets and potential treatments against various diseases such as cancer and neurodegenerative and infectious diseases have been identified. The objective of this review is to contribute to the literature in Spanish on the use of Artificial Intelligence and machine learning in drug repositioning research.

Resistant starches are made up of two polymers, amylose and amylopectin that have the ability to resist digestion and remain intact in the intestine, they have been linked to the prevention and control of diseases including obesity, diabetes mellitus, cardiovascular disease and cancer. According to various investigations, it was determined that resistant starch meets the necessary characteristics to be catalogued a probiotic. The adequate consumption of these fibers that are found in cereals, legumes and tubers could help reduce the comorbidities caused by the diseases mentioned. The objective of this revision assignment is to identify information about the benefits of resistant starches and it relationship to health.

The Creole Mexican chickens present a wide variation of their morphometric characteristics that go from the shape of the bird to the shape, weight, and size of the eggs they lay, offering different biological-productive values. This research consisted of describing the morphometric parameters of their eggs, and their reproductive potential under artificial incubation. For this, 2,778 eggs were collected from an experimental population of the Colegio de Postgraduados, Campus Montecillo, of which the measures corresponding to the macrostructure were recorded and were studied through multivariate cluster analysis. 2,671 eggs were placed for artificial incubation, distributed in eight blocks, and their development was described by embryodiagnostic analysis. As a result of the cluster, a dendrogram with three groups was obtained, group 2 grouped most of the data and could be considered as the morphometric standard with average measurements of weight = 55.96 g, length = 5.72 cm, width = 4.18 cm, egg shape index = 73, volume = 51.09 cm3, area 67.48 cm2 and color on the Zinpro® scale = 5. A fertility percentage of 76.46% and a birth percentage of 21.61% were achieved through artificial incubation.

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease characterized by an aberrant and deregulated remodeling process, where the immune system plays an important role, with smoking being the main risk factor. Cigarette smoke extract (CSE) induces damage and synthesis of cytokines in the epithelium of the respiratory tract. The CCL2 chemokine is elevated in the bronchoalveolar lavage of patients with IPF. However, it is unknown whether CSE induces its profibrotic effect through CCL2. The objective of the study is to evaluate the role of CCL2 in the migration and expression of profibrotic molecules using an In vitro model of A549 lung epithelial cells transfected with the CCL2 gene and CSE-stimulated CCD25 fibroblasts. Our findings indicate that CSE increases the expression of CCL2 and modulates the migration and proliferation of A549 cells and the expression and synthesis of TGF-β1. The conditioned medium of A549 cells that overexpress CCL2 induces migration and overexpression of IL6 in fibroblasts. CCL2 overexpression in CSE-stimulated A549 cells induces a profibrotic effect in CCD25 fibroblasts, serving as an orchestrator in the development of IPF.

Litchi chinensis is a fruit tree known as litchi or lychee, of the Sapindaceae family and native to southern China. It is currently cultivated in more than 20 countries with tropical and subtropical areas. The fruit has a high nutritional and commercial value due to its pleasant flavor, juicy aril, and attractive deep red color. In ancient times, various cultures used it as a traditional medicine to treat different diseases, including coughs, ulcers, diabetes, obesity, and epigastric and neuralgic pains. In the literature, litchi and its different parts (leaves, flowers, pulp, seed, and pericarp) are reported to have a high amount of bioactive compounds, with strong biological activity as antioxidant, antimicrobial, antiviral, antidiabetic, anticancer, anti-obesity, anti-inflammatory, hepatoprotective and analgesic. This review describes its botanical characteristics, distribution, and chemical composition with emphasis on the bioactive compounds it contains and its biological activity, as well as its uses, applications, and perspectives of interest for the food, pharmaceutical, and cosmetic industries in order to develop novel products useful for humans.