Controlling Painters' Exposure to Volatile Organic Solvents in the Automotive Sector of Southern Colombia

Belky P. Castaño,Vladimir Ramírez,Julio A. Cancelado 한국산업안전보건공단 산업안전보건연구원 2019 Safety and health at work Vol.10 No.3

Background: Painters in the automotive sector are routinely exposed to volatile organic solvents, and the levels vary depending on the occupational health and safety controls enforced at the companies. This study investigates the levels of exposure to organic vapors and the existence of controls in the formal economy sector in southern Colombia. Methods: This is an exploratory study of an observational and descriptive character. An analysis of solvents is conducted via the personal sampling of painters and the analysis of samples using the National Institute for Occupational Safety and Health 1501 method. The amount of solvents analyzed varied according to the budget allocated by the companies. The person in charge of the occupational safety and health management system was interviewed to learn about the exposure controls implemented at the companies. Results: A medium exposure risk for toluene was found in one company. Another presented medium risk for carbon tetrachloride, xylene, ethylbenzene, and n-butanol. The others showed low risk of exposure and that the controls implemented were not sufficient or efficient. Conclusion: These results shed light on the working conditions of these tradespeople. The permissible limits established by Colombian regulations for the evaluated chemical contaminants were not exceeded. However, there were contaminants that exceeded the limits of action. The analysis of findings made it possible to propose improvements in occupational safety and health management systems to allow the optimization of working conditions for painters, prevent the occurrence of occupational diseases, and reduce costs to the country’s health system.

Transcription Factors Tec1 and Tec2 Play Key Roles in the Hyphal Growth and Virulence of Mucor lusitanicus Through Increased Mitochondrial Oxidative Metabolism

Alejandre-Castañeda Viridiana,Patiño-Medina J. Alberto,Valle-Maldonado Marco I.,García Alexis,Ortiz-Alvarado Rafael,Ruíz-Herrera León F.,Castro-Cerritos Karla Viridiana,Ramírez-Emiliano Joel,Ramírez-D 한국미생물학회 2023 The journal of microbiology Vol.61 No.12

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. This study aimed to investigate the role of Tec proteins, which belong to the TEA/ATTS transcription factor family, in the hyphal development and virulence of M. lusitanicus. Unlike in the genome of Ascomycetes and Basidiomycetes, which have a single Tec homologue, in the genome of Mucorales, two Tec homologues, Tec1 and Tec2, were found, except in that of Phycomyces blakesleeanus, with only one Tec homologue. tec1 and tec2 overexpression in M. lusitanicus increased mycelial growth, mitochondrial content and activity, expression of the rhizoferrin synthetase-encoding gene rfs, and virulence in nematodes and wax moth larvae but decreased cAMP levels and protein kinase A (PKA) activity. Furthermore, tec1- and tec2-overexpressing strains required adequate mitochondrial metabolism to promote the virulent phenotype. The heterotrimeric G beta subunit 1-encoding gene deletant strain (Δgpb1) increased cAMP-PKA activity, downregulation of both tec genes, decreased both virulence and hyphal development, but tec1 and tec2 overexpression restored these defects. Overexpression of allele-mutated variants of Tec1(S332A) and Tec2(S168A) in the putative phosphorylation sites for PKA increased both virulence and hyphal growth of Δgpb1. These findings suggest that Tec homologues promote mycelial development and virulence by enhancing mitochondrial metabolism and rhizoferrin accumulation, providing new information for the rational control of the virulent phenotype of M. lusitanicus.

Pathogenic potential of non-typhoidal Salmonella serovars isolated from aquatic environments in Mexico

Areli Burgueño‑Roman,Gloria M. Castañeda‑Ruelas,Ramón Pacheco‑Arjona,Maribel Jimenez‑Edeza 한국유전학회 2019 Genes & Genomics Vol.41 No.7

Background River water has been implicated as a source of non-typhoidal Salmonella (NTS) serovars in Mexico. Objective To dissect the molecular pathogenesis and defense strategies of seven NTS strains isolated from river water in Mexico. Methods The genome of Salmonella serovars Give, Pomona, Kedougou, Stanley, Oranienburg, Sandiego, and Muenchen were sequenced using the whole-genome shotgun methodology in the Illumina Miseq platform. The genoma annotation and evolutionary analyses were conducted in the RAST and FigTree servers, respectively. The MLST was performed using the SRST2 tool and the comparisons between strains were clustered and visualized using the Gview server. Experimental virulence assay was included to evaluate the pathogenic potential of strains. Results We report seven high-quality draft genomes, ranging from ~ 4.61 to ~ 5.12 Mb, with a median G + C value, coding DNA sequence, and protein values of 52.1%, 4697 bp, and 4,589 bp, respectively. The NTS serovars presented with an open pan-genome, offering novel genetic content. Each NTS serovar had an indistinguishable virulotype with a core genome (352 virulence genes) closely associated with Salmonella pathogenicity; 13 genes were characterized as serotype specific, which could explain differences in pathogenicity. All strains maintained highly conserved genetic content regarding the Salmonella pathogenicity islands (1–5) (86.9–100%), fimbriae (84.6%), and hypermutation (100%) genes. Adherence and invasion capacity were confirmed among NTS strains in Caco-2 cells. Conclusion Our results demonstrated the arsenal of virulence and defense molecular factors harbored on NTS serovars and highlight that environmental NTS strains are waterborne pathogens worthy of attention.

Prediction of tenderness in bovine longissimus thoracis et lumborum muscles using Raman spectroscopy

Coria Maria Sumampa,Castaño Ledesma María Sofía,Gómez Rojas Jorge Raúl,Grigioni Gabriela,Palma Gustavo Adolfo,Borsarelli Claudio Darío 아세아·태평양축산학회 2023 Animal Bioscience Vol.36 No.9

Objective: This study was conducted to evaluate Raman spectroscopy technique as a noninvasive tool to predict meat quality traits on Braford longissimus thoracis et lumborum muscle. Methods: Thirty samples of muscle from Braford steers were analyzed by classical meat quality techniques and by Raman spectroscopy with 785 nm laser excitation. Water holding capacity (WHC), intramuscular fat content (IMF), cooking loss (CL), and texture profile analysis recording hardness, cohesiveness, and chewiness were determined, along with fiber diameter and sarcomere length by scanning electron microscopy. Warner-Bratzler shear force (WBSF) analysis was used to differentiate tender and tough meat groups. Results: Higher values of cohesiveness and CL, together with lower values of WHC, IMF, and shorter sarcomere were obtained for tender meat samples than for the tougher ones. Raman spectra analysis allows tender and tough sample differentiation. The correlation between the quality attributes predicted by Raman and the physical measurements resulted in values of R2 = 0.69 for hardness and 0,58 for WBSF. Pearson's correlation coefficient of hardness (r = 0.84) and WBSF (r = 0.79) parameters with the phenylalanine Raman signal at 1,003 cm–1, suggests that the content of this amino acid could explain the differences between samples. Conclusion: Raman spectroscopy with 785 nm laser excitation is a suitable and accurate technique to identify beef with different quality attributes.

A Mild Thermal Pre-treatment of the Organic Fraction of Municipal Wastes Allows High Ethanol Production by Direct Solid-state Fermentation

R. Estrada-Martínez,E. Favela-Torres,N. O. Soto-Cruz,H. B. Escalona-Buendía,G. Saucedo-Castañeda 한국생물공학회 2019 Biotechnology and Bioprocess Engineering Vol.24 No.2

A solid standard mixture (SSM) representing the annual composition of fresh fruits and vegetables residues generated at the Supply Center in Mexico City was used for bioethanol production. This type of residues allows bioethanol production with a single thermal pretreatment instead of hard thermochemical or enzymatic treatments. The release of fermentable carbohydrates from the SSM by a mild thermal pretreatment was firstly optimized. After that, mixed and single cultures of Saccharomyces cerevisiae, Scheffersomyces stipitis, and Schwanniomyces occidentalis were evaluated for bioethanol production. The maximum ethanol production, 282.61 ± 13.09 L ethanol per ton of dry matter (DM), was reached using a severity factor (SF) of 2.35 and a mixed culture composed of Saccharomyces cerevisiae, Scheffersomyces stipitis, and Schwanniomyces occidentalis. The improved lab scale conditions were evaluated in a pilot scale (18 Kg) stirred bioreactor with an SF of 2.35 and the mixed culture, obtaining 245.72 ± 17.76 L ethanol per ton DM. The obtained results demonstrate for the first time the use of fresh fruits and vegetables residues for bioethanol production under solid-state culture conditions without any thermochemical or enzymatic pre-treatment.

Reaction network of the chloromethane conversion into light olefins using a HZSM-5 zeolite catalyst

Monica Gamero,Beatriz Valle,Pedro Castaño,Andrés T. Aguayo,Javier Bilbao 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.61 No.-

The second step of chlorine-mediated methane valorization into hydrocarbons has been investigated using a HZSM-5 zeolite catalyst. A parametric study has enabled to set the reaction network, which is dominated by the dual cycle mechanism and secondary reactions of light olefins. This network explains the formation of methane, light olefins, C5+ aliphatics, paraffins, aromatics and coke. Under the optimal conditions, the light olefin selectivity is >70%, of which >40% corresponds to propylene. Coke is originated in the zeolite micropores and then grows within the matrix meso- and macropores.

Regions of the human renal artery: histomorphometric analysis

Blanca Mompeó-Corredera,Pablo Hernández-Morera,Irene Castaño-González,María del Pino Quintana-Montesdeoca,Natalia Mederos-Real 대한해부학회 2022 Anatomy & Cell Biology Vol.55 No.3

The renal artery is frequently involved in the pathogenesis of vasculorenal diseases, and it is a target in kidney surgery and therapeutic techniques for refractory hypertension. However, few detailed structural studies on the human renal artery have been conducted. Using histocytochemistry, immunohistochemistry, and quantitative image analysis, the wall thickness, structure, smooth muscle cells, extracellular matrix, and proportion of elastic tissue in the tunica media of main human renal arteries were used estimated. Ninety-six tissue samples were collected from sections of the right and left main renal arteries. The results showed that the renal artery changed from an elastic vessel in its proximal segment to a muscular artery in its distal part. A critical characteristic of the renal artery was the presence of longitudinal smooth muscle cell formations in the tunica adventitia of middle and distal segments but not in the proximal part of the artery. In addition, the tunica adventitia of the renal artery showed a rich vascularization and the presence of numerous nerves profiles. The artery's regional structural and morphometric features explain that a particular arterial pathology is more frequent in a specific vessel sector than in others. In addition, those characteristics could determine a different therapeutic response attending to the arterial sector.

Correlation of the Holes Quality with the Force Signals in a Microdrilling Process of a Sintered Tungsten-Copper Alloy

Gerardo Beruvides,Ramón Quiza,Raúl del Toro,Fernando Castaño,Rodolfo E. Haber 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

Holes quality errors are an undesired but unavoidable consequence in drilling operations. Due to the small dimensions involved inthe microdrilling processes, quality measurement and control must be carried out offline, by using microscopy or other high precisionmeasurement devices. This paper presents a study about the correlation between the holes quality and the force signals in themicrodilling process of 0.1 mm and 0.5 mm-diameter holes in a sintered tungsten-copper alloy. The surface of the obtained holes wasscanned by means of an interferometry microscope and the error of the holes was computed from the scanned data. The threecomponents of the forces were measured during all the drilling process. The behavior of these signals, in three different intervals (toolentrance, forward motion and backward motion) was described by wavelet package analysis. The features having higher correlationwith the holes quality error were the average power of the axial component of the forces in the frequency bands of 0~391 Hz and3906~4297 Hz, during the backward motion. With these features, a statistical regression model was fitted. The main outcomes of thisstudy are the basement for obtaining reliable models for monitoring systems in microdrilling operations.

Genotype–environment interaction for milk production of Gyr cattle in Brazil and Colombia

Alejandra Maria Toro‑Ospina,Ricardo Antonio Faria,Dominguez-Castaño Pablo,Santana Mario Luiz,Gonzalez Luis Gabriel,Espasandin Ana Carolina,Silva Josineudson Augusto II Vasconcelos 한국유전학회 2023 Genes & Genomics Vol.45 No.2

Background Genotype by environment interactions (G × E) can play an important role in cattle populations and should be included in breeding programs in order to select the best animals for different environments. Objective The aim of this study was to investigate the G × E for milk production of Gyr cattle in Brazil and Colombia by applying a reaction norm model used genomics information, and to identify genomic regions associated with milk production in the two countries. Methods The Brazilian and Colombian database included 464 animals (273 cows and 33 sires from Brazil and 158 cows from Colombia) and 27,505 SNPs. A two-trait animal model was used for milk yield adjusted to 305 days in Brazil and Colombia as a function of country of origin, which included genomic information obtained with a single-step genomic reaction norm model. The GIBBS3F90 and POSTGSf90 programs were used. Results The results obtained indicate G × E based on the reranking of bulls between Brazil and Colombia, demonstrating environmental differences between the two countries. The findings highlight the importance of considering the environment when choosing breeding animals in order to ensure the adequate performance of their progeny. Within this context, the reranking of bulls and the different SNPs associated with milk production in the two countries suggest that G × E is an important effect that should be included in the genetic evaluation of Dairy Gyr cattle in Brazil and Colombia. Conclusion The Gyr breeding program can be optimized by choosing a selection environment that will allow maximum genetic progress in milk production in different environments within and between countries.

The Combination of Naproxen and Citral Reduces Nociception and Gastric Damage in Rats

Mario I. Ortiz,Martha L. Ramírez-Montiel,Martha P. González-García,Héctor A. Ponce-Monter,Gilberto Castañeda-Hernández,Raquel Cariño-Cortés 대한약학회 2010 Archives of Pharmacal Research Vol.33 No.10

It has been shown that the association of non-steroidal anti-inflammatory drugs with plant extracts can increase their antinociceptive activity, allowing the use of lower doses and, thus, limiting side effects. Therefore, the aim of this study was to examine the effects of the interaction between naproxen and citral on nociception and gastric injury in rats. Naproxen, citral, or combinations of naproxen and citral produced an antinociceptive effect. The administration of naproxen produced significant gastric damage, but this effect was not obtained with either citral or the naproxen-citral combination. The ED50 value was estimated for the individual drugs and an isobologram was constructed. The derived theoretical ED50 for the antinociceptive effect (423.8 mg/kg) was not significantly different from the observed experimental value (359.0 mg/kg); hence, the interaction between naproxen and citral mediating the antinociceptive effect is additive. These data suggest that the naproxen-citral combination interacts at the systemic level, produces minor gastric damage, and potentially has therapeutic advantages for the clinical treatment of inflammatory pain.