A Study of Resistome in Mexican Chili Powder as a Public Health Risk Factor.

Chili powder is an important condiment around the world. However, according to various reports, the presence of pathogenic microorganisms could present a public health risk factor during its consumption. Therefore, microbiological quality assessment is required to understand key microbial functional traits, such as antibiotic resistance genes (ARGs). In this study, metagenomic next-generation sequencing (mNGS) and bioinformatics analysis were used to characterize the comprehensive profiles of the bacterial community and antibiotic resistance genes (ARGs) in 15 chili powder samples from different regions of Mexico. The initial bacterial load showed aerobic mesophilic bacteria (AMB) ranging between 6 × 103 and 7 × 108 CFU/g, sporulated mesophilic bacteria (SMB) from 4.3 × 103 to 2 × 109 CFU/g, and enterobacteria (En) from <100 to 2.3 × 106 CFU/g. The most representative families in the samples were Bacillaceae and Enterobacteriaceae, in which 18 potential pathogen-associated species were detected. In total, the resistome profile in the chili powder contained 68 unique genes, which conferred antibiotic resistance distributed in 13 different classes. Among the main classes of antibiotic resistance genes with a high abundance in almost all the samples were those related to multidrug, tetracycline, beta-lactam, aminoglycoside, and phenicol resistance. Our findings reveal the utility of mNGS in elucidating microbiological quality in chili powder to reduce the public health risks and the spread of potential pathogens with antibiotic resistance mechanisms.

Establishing a Disease-in-a-Dish Model to Study SARS-CoV-2 Infection During Prenatal Development.

Mother-to-fetus transmission of the SARS-CoV-2 virus via the placenta has been reported but cannot readily be studied in pregnant women. This protocol describes an in vitro method to investigate SARS-CoV-2 infection of human embryonic stem cells (hESCs), which are similar to epiblast cells in young postimplantation embryos. First, SARS-CoV-2 viral pseudoparticles, which contain the spike protein and a fluorescent reporter, are incorporated into a lentivirus backbone that is expanded in HEK 293T cells. Then, an infection assay based on hESCs is used with the viral pseudoparticles. An application of the infection assay in therapeutic drug screening is provided. This protocol allows infection of hESCs by SARS-CoV-2 pseudoparticles to be studied in vitro and can be used in conjunction with other assays to understand and potentially prevent infection. hESCs could also be differentiated to study infection in the three germ layers and their fetal cell derivatives. This disease-in-a-dish model could be readily applied to other hESC lines, and to other viral infections, that affect human prenatal development. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Preparing HEK 293T cells for lentiviral vector transfection Support Protocol 1: Visual inspection of transfected HEK 293T cells Basic Protocol 2: Generating viral pseudoparticles Support Protocol 2: Determining viral titer with HEK 293T-ACE2 cells Basic Protocol 3: Plating hESCs for the infection assay Support Protocol 3: Evaluating transduction efficiency.

Correction to: Evaluation of the presence of Paenibacillus larvae in commercial bee pollen using PCR amplification of the gene for tRNACys.

In the article mentioned above an author's name was misspelled.

Evaluation of the presence of Paenibacillus larvae in commercial bee pollen using PCR amplification of the gene for tRNACys.

American foulbrood (AFB) caused by Paenibacillus larvae is the most destructive honeybee bacterial disease and its dissemination via commercial bee pollen is an important mechanism for the spread of this bacterium. Because Mexico imports bee pollen from several countries, we developed a tRNACys-PCR strategy and complemented that strategy with MALDI-TOF MS and amplicon-16S rRNA gene analysis to evaluate the presence of P. larvae in pollen samples. P. larvae was not detected when the tRNACys-PCR approach was applied to spore-forming bacterial colonies obtained from three different locations and this result was validated by bacterial identification via MALDI-TOF MS. The genera identified in the latter analysis were Bacillus (fourteen species) and Paenibacillus (six) species. However, amplicon-16S rRNA gene analysis for taxonomic composition revealed a low presence of Paenibacillaceae with 0.3 to 16.2% of relative abundance in the commercial pollen samples analyzed. Within this family, P. larvae accounted for 0.01% of the bacterial species present in one sample. Our results indicate that the tRNACys-PCR, combined with other molecular tools, will be a useful approach for identifying P. larvae in pollen samples and will assist in controlling the spread of the pathogen.

Mercury concentrations in common carp (Cyprinus carpio) in Lake Chapala, Mexico: a lakewide survey.

Previous studies, based on limited data, found elevated levels of mercury in carp in Lake Chapala, Mexico. The extent of mercury contamination in carp throughout the Lake has not been determined. In order to obtain reliable information about total mercury concentration in carp (Cyprinus carpio), 262 fish from 27 sites (approximately 10 fish per site) throughout the lake were analyzed. Results were expressed as the mean and median of the results at each site. Only one of the samples exceeded Mexican National Standard (1.0 ppm) for mercury in fish flesh. We discuss these results in comparison to World Health Organization (WHO), US Food and Drug Administration (FDA) and US Environmental Protection Agency (US EPA) criteria; many of our samples exceed these criteria based on Tolerable Daily Intake (TDI) or Reference Dose (RfD). ANOVA of four groups of mercury results clustered by distance from the Lerma showed statistically significant differences (P = 0.0071) between the group closest to, versus farthest from, the Lerma River.

Prevalencia de diabetes mellitus e hiperlipidemias en indígenas otomíes / Prevalence of diabetes mellitus and hyperlipidemias in Otomi indians

Objetivo. Determinar prevalencia y factores de riesgo de la diabetes mellitus (DM) e hiperlipidemias en un grupo de indígenas otomíes de Querétaro. Material y métodos. Entre 1996 y 1997, en muestreo de conveniencia se trabajó con 91 indígenas, de 15 a 77 años de edad, de las comunidades de Yosphí y El Rincón, del estado de Querétaro, México. Se tomaron muestras sanguíneas en ayuno y se determinó la concentración de glucosa, colesterol y triglicéridos. Se realizó análisis estadístico para comparación entre sexos y grupos de edad. Resultados. La prevalencia de DM fue 4.4 por ciento, la de hipercolesterolemia 7.2 por ciento, y la de hipertrigliceridemia (HTG) 26 por ciento. Las concentracio-nes promedio de glucosa (81.0ñ24.4 mg/dl) y triglicéridos (157.4ñ88.9 mg/dl) se incrementaron significativamente con la edad (p=0.0279 y p<0.0001 respectivamente), de igual manera para la prevalencia de HTG (p<0.0001). Conclusiones. Los resultados sugieren que cambios drásticos en los patrones tradicionales de alimentación que conservan los indígenas otomíes pueden originar problemas de salud asociados a la elevación de lípidos en sangre. El texto completo en inglés de este artículo está disponible en: http://www.insp.mx/salud/index.html