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A raíz de la pandemia, una de las actividades económicas más afectadas fue la gastronomía, debido a las restricciones para mitigar los contagios. La presente investigación tiene como objetivo determinar los factores que influyen en la rentabilidad de las Pequeñas y Medianas Empresas chilenas del sector gastronómico, desde la perspectiva contingente y de recursos y capacidades. Para ello se realizó una investigación cuantitativa con una muestra de 59 empresas. Los resultados del análisis de regresión logística indican que, cuando las empresas despiden tres o menos trabajadores, la probabilidad de que su rendimiento aumente o se mantenga igual se incrementa en un 422%. Por otro lado, por cada decisión adicional que toma la empresa, la probabilidad de que su rendimiento se mantenga igual o aumente disminuye en un 51%. La tecnología y el tamaño no fueron relevantes para este tipo de empresas.

Toxic lead (Pb) in end-of-life silicon solar modules must be recovered to keep it out of the environment. Present literature on Pb recovery from solar waste is sparse and uses chemicals like nitric or hydrochloric acid. Previously, the authors reported Pb recovery from silicon modules by leaching and electrowinning in acetic acid. However, the Pb recovered from acetic solution contained a small amount of metallic Pb with the rest being lead oxides/acetates. These Pb compounds require further processing to obtain metallic Pb for reuse in solar panel solder, leading to additional cost and chemical waste. This paper reports recovery of metallic Pb using an electrochemical system with two half cells connected through a salt bridge. The salt bridge enables optimized recovery rates of Pb as high as 99.99 % for synthetic leachates. The first experiment to recover Pb from real silicon module waste shows 80 % recovery without optimization. The new method offers a low-cost, closed-loop, direct pathway to metallic Pb recovery from end-of-life silicon solar modules for reuse in new modules.

La presencia de Arsénico en agua de consumo humano se ha vuelto un problema se salud pública a nivel mundial. En México, se ha reportado la exposición a este contaminante en diferentes estados de la república, y se ha asociado con diversas afectaciones a la salud. Utilizando la base de datos científica PubMed, se introdujeron las palabras clave Arsénico, Agua y México a fin de recopilar los estudios existentes sobre las concentraciones de Arsénico en agua en diferentes sitios de la república, así como de los efectos en la salud de poblaciones mexicanas expuestas. Después del análisis se encontró asociación con enfermedades metabólicas y cardiopulmonares, así como la presencia de indicios de daño renal y al ADN. Todo esto muestra la necesidad de contar con estrategias de remoción y, sobre todo, políticas públicas más estrictas y aplicables que puedan ayudar a mejorar la salud pública en nuestro país.

Thirty years since the first report on the PilY1 protein in bacteria, only the C-terminal domain has been crystallized; there is no study in which the N-terminal domain, let alone the complete protein, has been crystallized. In our laboratory, we are interested in characterizing the Type IV Pili (T4P) of Acidithiobacillus thiooxidans. We performed an in silico characterization of PilY1 and other pilins of the T4P of this acidophilic bacterium. In silico characterization is crucial for understanding how proteins adapt and function under extreme conditions. By analyzing the primary and secondary structures of proteins through computational methods, researchers can gain valuable insights into protein stability, key structural features, and unique amino acid compositions that contribute to resilience in harsh environments. Here, it is presented a description of the particularities of At. thiooxidans PilY1 through predictor software and homology data. Our results suggest that PilY1 from At. thiooxidans may have the same role as has been described for other PilY1 associated with T4P in neutrophilic bacteria; also, its C-terminal interacts (interface interaction) with the minor pilins PilX, PilW and PilV. The N-terminal region comprises domains such as the vWA and the MIDAS, involved in signaling, ligand-binding, and protein-protein interaction. In fact, the vWA domain has intrinsically disordered regions that enable it to maintain its structure over a wide pH range, not only at extreme acidity to which At. thiooxidans is adapted. The results obtained helped us design the correct methodology for its heterologous expression. This allowed us partially experimentally characterize it by obtaining the N-terminal domain recombinantly and evaluating its acid stability through fluorescence spectroscopy. The data suggest that it remains stable across pH changes. This work thus provides guidance for the characterization of extracellular proteins from extremophilic organisms.

La obesidad se ha convertido en los últimos años en una pandemia alrededor del mundo, y se ha hecho acompañar de enfermedades fatales como el cáncer. De manera reciente se ha investigado la relación que juega la obesidad y el sobrepeso en la incidencia del cáncer. Se utilizaron las palabras clave como: citocinas inflamatorias, obesidad, cáncer e inflamación para realizar una búsqueda bibliográfica en las bases de datos científicas World Wide Science, Springer Link, PubMed y Google Scholar; para describir la relación entre la obesidad y el cáncer. Estudios reportados han podido establecer la conexión que existe entre la obesidad y el alza del riesgo de diferentes tipos de cáncer. Se ha reportado que un cambio en el estilo de vida y en la dieta puede prevenir del 30 al 50 % de las enfermedades. Es importante poder dar a conocer que la obesidad es la segunda causa prevenible de...

Background: MicroRNAs (miRNAs) are important regulators in a variety of biological processes, and their dysregulation is associated with multiple human diseases. Single nucleotide variants (SNVs) in genes involved in the processing of microRNAs may alter miRNA regulation and could present high allele heterogeneity in populations from different ethnic groups. Thus, the aim of this study was to genotype 15 SNVs in eight genes involved in the miRNA processing pathway in Mexican individuals and compare their frequencies across 21 populations from five continental groups.Methods: Genomic DNA was obtained from 399 healthy Mexican individuals. SNVs in AGO2 (rs2293939 and rs4961280), DGCR8 (rs720012), DICER (rs3742330 and rs13078), DROSHA (rs10719 and rs6877842), GEMIN3 (rs197388 and rs197414), GEMIN4 (rs7813, rs2740349, and rs4968104), TNRC6B (rs9611280), and XP05 (rs11077 and rs34324334) were genotyped using TaqMan probes. The minor allele frequency of each SNV was compared to those reported in the 1,000 Genomes database using chi-squared. Sankey plot was created in the SankeyMATIC package to visualize the frequency range of each variant in the different countries analyzed.Results: In Mexican individuals, all 15 SNVs were found in Hardy-Weinberg equilibrium, with frequencies ranging from 0.04 to 0.45. The SNVs rs4961280, rs2740349, rs34324334, and rs720012 in Mexican individuals had the highest minor allele frequencies worldwide, whereas the minor allele frequencies of rs197388, rs10719, rs197414, and rs1107 were among the lowest in Mexican individuals. The variants had high allele heterogeneity among the sub-continental populations, ranging from monomorphic, as was the case for rs9611280 and rs34324334 in African groups, to >0.50, which was the case for variants rs11077 and rs10719 in most of the populations. Importantly, the variants rs197388, rs720012, and rs197414 had FST values > 0.18, indicating a directional selective process. Finally, the SNVs rs13078 and rs10719 significantly correlated with both latitude and longitude.Conclusion: These data indicate the presence of high allelic heterogeneity in the worldwide distribution of the frequency of SNVs located in components of the miRNA processing pathway, which could modify the genetic susceptibility associated with human diseases in populations with different ancestry.

Los principales polinizadores de la flora silvestre son las abejas sin aguijón y los productos del nido como el polen recolectado, el propóleo y principalmente la miel; han sido empleados en la dieta diaria y aún mejor en la medicina tradicional. Empleando palabras clave como: actividad antimicrobiana, antioxidante, antibacteriana y anticancerígena se realizó una búsqueda bibliográfica en libros y artículos de investigación de los buscadores científicos PubMed, World Wide Science, Google Scholar y Springer Link, para describir aspectos generales y ejemplos de los beneficios en la salud de la miel. Estudios in vitro e in vivo han demostrado una relación positiva entre las características fisicoquímicas y la composición fitoquímica de la miel con el efecto benéfico en el tratamiento de afecciones leves como cicatrización de heridas, hasta procesos complejos de inflamación, estrés oxidativo, o infecciones microbianas. Así, la miel de abejas sin aguijón representa un producto con potencial terapéutico.

Pyrite bio-oxidation by chemolithotrophic acidophile bacteria has been applied in the mining industry to bioleach metals or to remove pyritic sulfur from coal. In this process, it is desirable to use autochthonous and already adapted bacteria isolated directly from the mining sites where biomining will be applied. Bacteria present in the remnant solution from a mining company were identified through cloning techniques. For that purpose, we extracted total RNA and performed reverse transcription using a novel pair of primers designed from a small region of the 16S gene (V1–V3) that contains the greatest intraspecies diversity. After cloning, a high proportion of individuals of the strains ATCC-23270 (NR_074193.1 and NR_041888.1) and DQ321746.1 of the well-known species Acidithiobacillus ferrooxidans were found, as well as two new wild strains of A. ferrooxidans. This result showed that the acidic remnant solution comprises a metapopulation. We assayed these strains to produce bioferric flocculant to enhance the subsequent pyrite bio-oxidation, applying two-stage chemical–bacterial oxidation. It was shown that the strains were already adapted to a high concentration of endogenous Fe2+ (up to 20 g·L−1), increasing the volumetric productivity of the bioferric flocculant. Thus, no preadaptation of the community was required. We detected Au and Ag particles originally occluded in the old pyritic flotation tailings assayed, but the extraction of Au and Ag by cyanidation resulted in ca. 30.5% Au and 57.9% Ag.

To document the epidemiology, clinical features, and outcomes of murine typhus patients in the Canary Islands (Spain), we analyzed data that were retrospectively collected for 16 years for 221 patients. Murine typhus in the Canary Islands is characterized by a high rate of complications (31.6%), mainly liver, lung, kidney or central nervous system involvement.

Introduction: the use of insulin in models of experimental diabetes is still controversial. Objective: to evaluate the effect of hyperglycemia for a long time at a systemic level in hyperglycemic subjects treated with insulin at non-normoglycemic doses. Methods: an experimental (analytical), longitudinal study conducted. Hyperglycemia (glucose levels ~ 500mg/dl) was induced in Wistar rats (hyperglycemic group, n=4); they were administered aloxan (intraperitoneal, 150mg/kg) and were protected, simultaneously, with insulin (0.25-0.5U/kg) for 42 days. Samples of liver, pancreas, kidney and retina were obtained and stained with the hematoxylin and eosin technique. Histological changes and cell count were identified when compared with normoglycemic rats (normoglycemic group, n=4) by Student’s t-test, p

Background. The clinical and epidemiological data of the recent outbreak of monkeypox (MPX) differ from previous reports. One difference is the epidemiological profile; the disease mainly affects a subgroup of MSM (men who have sex with men) with high-risk sexual behaviors, frequently persons living with human immunodeficiency virus (PLHIV). Methods. In this observational analysis, all patients with PCR (polymerase chain reaction)-confirmed MPX attending an Infectious Diseases and Tropical Medicine Unit in Gran Canaria (Spain) between May and July 2022 were considered. Results. In total, 42 men were included; 88% were identified as MSM, with a median age of 40 years. Only 43% were born in Spain. All the patients had systemic symptoms and skin lesions. The distribution of lesions was more frequent in the genital/anal region, and the involvement of hands and feet was less common. Fever and lymphadenopathies were less frequent than in other series. Other unusual manifestations were proctitis, pharyngitis and penile–scrotal edema. Half of the patients had other associated infections (mainly STIs, sexually transmitted infections), and 60% of the monkeypox patients had PLHIV (People Living with HIV). When comparing the clinical characteristics between HIV-positive and -negative patients, we found three main differences: (i) a higher frequency of perioral lesions, (ii) a higher frequency of pharyngitis and (iii) a higher number of sexually transmitted infections in HIV-positive patients. Conclusions. The clinical findings in this outbreak of MPX had great variability in presentation. Several clinical differences were found in PLHIV-coinfected patients.

Compared to companies that do not market products abroad, import export businesses face an additional risk: foreign exchange volatility. This work analyzes the features that distinguish the management strategies of highly profitable companies that conduct international businesses in Oaxaca and Mexico City in contingency environments—the 2014-2016 foreign exchange risk—from low-profit ones. According to the contingency theory, the former use different mechanisms to adapt to changes in the environment. Logistic Regression (LR) was used to classify companies with profits above 20 % based on their management features. To characterize the management style, 23 explanatory variables were employed; they dealt with aspects related to the administrator and the cover schemes. The results revealed that only 4, out of those 23, were statistically significant for companies to achieve high profit margins and the use of derivative instruments stood out as a decisive factor.

Acidithiobacillus thiooxidans is an acidophilic chemolithoautotrophic bacterium widely used in the mining industry due to its metabolic sulfur-oxidizing capability. The biooxidation of sulfide minerals is enhanced through the attachment of At. thiooxidans cells to the mineral surface. The Type IV pili (TfP) of At. thiooxidans may play an important role in the bacteria attachment since TfP play a key adhesive role in the attachment and colonization of different surfaces. In this work, we report for the first time the mRNA sequence of three TfP proteins from At. thiooxidans, the adhesin protein PilY1 and the TfP pilins PilW and PilV. The nucleotide sequences of these TfP proteins show changes in some nucleotide positions with respect to the corresponding annotated sequences. The bioinformatic analyses and 3D-modeling of protein structures sustain their classification as TfP proteins, as structural homologs of the corresponding proteins of Ps. aeruginosa, results that sustain the role of PilY1, PilW and PilV in pili assembly. Also, that PilY1 comprises the conserved Neisseria-PilC (superfamily) domain of the tip-associated adhesin, while PilW of the superfamily of putative TfP assembly proteins and PilV belongs to the superfamily of TfP assembly protein. In addition, the analyses suggested the presence of specific functional domains involved in adhesion, energy transduction and signaling functions. The phylogenetic analysis indicated that the PilY1 of Acidithiobacillus genus forms a cohesive group linked with iron- and/or sulfur-oxidizing microorganisms from acid mine drainage or mine tailings.

Diabetes mellitus is the most common chronic disease worldwide that causes numerous complications, including male infertility. The prevalence of DM is 451 million people and estimated that would increase to 693 million in 2045. Fluorosis caused by drinking water contaminated with inorganic fluoride is a public health problem in many areas around the world. Previous studies have shown that fluoride exposure damages the male reproductive function. This study aimed to evaluate the fluoride sub-chronic exposure on the spermatozoa function in streptozotocin (STZ)-induced diabetic mice. After confirming diabetes by measuring blood glucose levels, the male mice received 45.2 ppm of fluoride added or deionized water. We evaluated several parameters in diabetic mice exposed to fluoride: standard quality analysis, the mitochondrial transmembrane potential (ψm), the caspase activity in spermatozoa, urinary fluoride excretion, and histological evaluation in the testes. After 60 days of fluoride-exposure, diabetic mice, significantly decreased sperm quality (motility, viability, and concentration). Spermatozoa from fluoride-exposure in diabetic mice presented a significant decrease in ψm and a significant increase in activity caspase 3/7. Urinary fluoride excretion was decreased in diabetic mice exposed to fluoride. Subchronic fluoride exposure of mice with STZ-induced diabetes aggravated testicular damage and the spermatozoa function.