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Time-temperature data for queso fresco (QF) cheese varieties stored in a residential refrigerator operating at 5°C and a predictive microbiology secondary model for Listeria monocytogenes in QF were used to estimate a refrigerator performance indicator (RPI) of microbial preservation. RPI values were used to assess how compressor technology (single [SS] and variable speed [VS]), ambient temperature (21.1°C [LT] and 32.2°C [HT]), and refrigerator load (22.5 kg regular load and 39 kg higher load) affected preservation performance. All deterministic and probabilistic RPI estimations slightly exceeded the desirable 1.0 value, i.e., the variable temperatures for the QF kept in the refrigerator were worse than keeping it constantly at the temperature recommended by food safety agencies for QF. Furthermore, the mean comparison of estimates of the time-temperature equivalent indicator previously developed by French researchers showed similar behavior to those observed for RPI. Finally, statistical analysis showed that Tambient was the factor with the highest impact on refrigerator performance because of its impact on the sample temperature increase during door openings and when exposed to ambient temperature during product use. This highlights the need to reduce the time for product temperature recovery by improving the compressor operation logic. Also important are consumer behavior changes such as a reduction in product exposure to ambient temperature and in the door opening duration and frequency. PRACTICAL APPLICATION: This study demonstrated how a quantitative tool (RPI) can assess refrigerator preservation performance. Although the findings presented can be applied to any cold chain segment, the data used was collected for its weakest link, the domestic refrigerator. Surveys show that 77% of them operate above the recommended 4°C. The RPI methodology is ready for use by refrigerator designers to assess performance improvements possible by modifications of the compressor operation logic. Moreover, it can be integrated into smart-hubs monitoring the frequency and duration of refrigerator door openings to inform consumers when their habits are compromising the preservation performance of the refrigerator.

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Rainbow trout is an important fish species for Peruvian artisanal aquaculture, comprising over 60 % of the total aquaculture production. However, their industry has been highly affected by several bacterial agents such as Yersinia ruckeri. This pathogen is the causative agent of Enteric Redmouth Disease, and causes high mortality in fingerlings and chronic infection in adult rainbow trout. To date, the immune response of rainbow trout against Y. ruckeri has been well studied in laboratory-controlled infection studies (i.e. intraperitoneal infection, bath immersion), however, the immune response during natural infection has not been explored. To address this, in this study, 35 clinically healthy O. mykiss without evidence of lesions or changes in behavior and 32 rainbow trout naturally infected by Y. ruckeri, were collected from semi-intensive fish farms located in the Central Highlands of Peru. To evaluate the effect on the immune response, RT-qPCR, western blotting, and ELISA were conducted using head kidney, spleen, and skin tissues to evaluate the relative gene expression and protein levels. Our results show a significant increase in the expression of the pro-inflammatory cytokines il1b, tnfa, and il6, as well as ifng in all three tissues, as well as increases in IL-1ß and IFN-γ protein levels. The endogenous pathway of antigen presentation showed to play a key role in defense against Y. ruckeri, due to the upregulation of mhc-I, tapasin, and b2m transcripts, and the significant increase of Tapasin protein levels in infected rainbow trout. None of the genes associated with the exogenous pathway of antigen presentation showed a significant increase in infected fish, suggesting that this pathway is not involved in the response against this intracellular pathogen. Finally, the transcripts of immunoglobulins IgM and IgT did not show a modulation, nor were the protein levels evaluated in this study.

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Uropathogenic Escherichia coli (UPEC) is the main cause of urinary tract infections (UTIs) and carries virulence and resistance factors often found in mobilizable genetic elements, such as plasmids or pathogenicity islands (PAIs). UPEC is part of the extraintestinal pathogenic E. coli (ExPEC), but hybrid strains possessing both diarrheagenic E. coli (DEC) and ExPEC traits, termed "hypervirulent", present a significant health threat. This study assessed the prevalence of UPEC PAIs, ExPEC sequence types (ST), DEC genes, carbapenemase and extended-spectrum ß-lactamase (ESBL) phenotypes, resistance genotypes, and plasmids in 40 clinical isolates of UPEC. Results showed that 72.5% of isolates had PAIs, mainly PAI IV536 (53%). ESBL phenotypes were found in 65% of ß-lactam-resistant isolates, with 100% of carbapenem-resistant isolates producing carbapenemase. The predominant ESBL gene was blaCTX-M-2 (60%), and the most common resistance gene in fluoroquinolone and aminoglycoside-resistant isolates was aac(6')Ib (93%). Plasmids were present in 57% of isolates, and 70% belonged to the ST131 clonal group. Molecular markers for DEC pathotypes were detected in 20 isolates, with 60% classified as hybrid pathotypes. These findings indicate significant pathogenic potential and the presence of hybrid pathotypes in E. coli UTI clinical isolates in the Mexican population.

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Interferon-gamma (IFN-γ) plays a dual role in cancer; it is both a pro- and an antitumorigenic cytokine, depending on the type of cancer. The deregulation of the IFN-γ canonic pathway is associated with several disorders, including vulnerability to viral infections, inflammation, and cancer progression. In particular, the interplay between lung adenocarcinoma (LUAD) and viral infections appears to exist in association with the deregulation of IFN-γ signaling. In this mini-review, we investigated the status of the IFN-γ signaling pathway and the expression level of its components in LUAD. Interestingly, a reduction in IFNGR1 expression seems to be associated with LUAD progression, affecting defenses against viruses such as severe acute respiratory syndrome coronavirus 2. In addition, alterations in the expression of IFNGR1 may inhibit the antiproliferative action of IFN-γ signaling in LUAD.

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Introduction: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. are microorganisms referred as the ESKAPE group pathogens. These microorganisms have generated great concern in health institutions around the world since most of them have resistance to multiple antibiotics and cause most infections associated with healthcare, as well as community infections. The aim of this study was the analysis of antibiotic resistance in microorganisms of the ESKAPE group, recovered from clinical samples in 11 health institutions from Hermosillo and Ciudad Obregón in the State of Sonora, México, during the period from 2019 to 2020. Methods: A cross-sectional, descriptive, observational, and temporality epidemiological study was carried out. A comparative and statistical analysis of antibiotic resistance was carried out using the chi-square test, and small values were analyzed using Fisher's exact test p ≤ 0.05. Results and discussion: All the ESKAPE group microorganisms showed significant differences in antibiotic resistance percentages between both cities. High resistance percentages for some antibiotics, like cephalosporins and ciprofloxacin were detected for Klebsiella pneumoniae and Acinetobacter baumannii.

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Brain physiology and morphology are vulnerable to chronic stress, impacting cognitive performance and behavior. However, functional compounds found in food may alleviate these alterations. White quinoa (Chenopodium quinoa, Wild) seeds contain a high content of n-3 fatty acids, including alpha-linolenic acid. This study aimed to evaluate the potential neuroprotective role of a quinoa-based functional food (QFF) in rats. Prepubertal male Sprague-Dawley rats were fed with rat chow or QFF (50% rat chow + 50% dehydrated quinoa seeds) and exposed or not to restraint stress protocol (2 h/day; 15 days). Four experimental groups were used: Non-stressed (rat chow), Non-stressed + QFF, Stressed (rat chow) and Stressed + QFF. Weight gain, locomotor activity (open field), anxiety (elevated plus maze, light-dark box), spatial memory (Y-maze), and dendritic length in the hippocampus were measured in all animals. QFF intake did not influence anxiety-like behaviors, while the memory of stressed rats fed with QFF improved compared to those fed with rat chow. Additionally, QFF intake mitigated the stress-induced dendritic atrophy in pyramidal neurons located in the CA3 area of the hippocampus. The results suggest that a quinoa-supplemented diet could play a protective role in the memory of chronically stressed rats.

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Biomass cookstove food preparation is linked to aero-digestive cancers, mediated by ingested and inhaled carcinogens (e.g., heterocyclic amines, and polycyclic aromatic hydrocarbons). We investigated the association between gastric adenocarcinoma, wood cookstove use, H. pylori CagA infection and risk modification by variants in genes that metabolize and affect the internal dose of carcinogens. We conducted a population-based, case-control study (814 incident cases, 1049 controls) in rural Honduras, a high-incidence region with a homogeneous diet and endemic H. pylori infection, primarily with the high-risk CagA genotype. We investigated factors including wood cookstove use, H. pylori CagA serostatus, and 15 variants from 7 metabolizing genes, and the interactions between wood stove use and the genetic variants. Male sex (OR 2.0, 1.6-2.6), age (OR 1.04, 1.03-1.05), wood cookstove use (OR 2.3, 1.6-3.3), and CagA serostatus (OR 3.5, 2.4-5.1) and two SNPs in CYP1B1 (rs1800440 and rs1056836) were independently associated with gastric cancer in multivariate analysis. In the final multivariate model, a highly significant interaction (OR 3.1, 1.2-7.8) was noted between wood cookstove use and the rs1800440 metabolizing genotype, highlighting an important gene-environment interaction. Lifetime wood cookstove use associates with gastric cancer risk in the high-incidence regions of Central America, and the association is dependent on the rs1800440 genotype in CYP1B1. H. pylori CagA infection, wood cookstove use and the rs1800440 genotype, all of which are highly prevalent, informs who is at greatest risk from biomass cookstove use.

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We analyzed the antimicrobial resistance (AMR) data of 6519 clinical isolates of Escherichia coli (n = 3985), Klebsiella pneumoniae (n = 775), Acinetobacter baumannii (n = 163), Pseudomonas aeruginosa (n = 781), Enterococcus faecium (n = 124), and Staphylococcus aureus (n = 691) from 43 centers in Mexico. AMR assays were performed using commercial microdilution systems (37/43) and the disk diffusion susceptibility method (6/43). The presence of carbapenemase-encoding genes was assessed using PCR. Data from centers regarding site of care, patient age, and clinical specimen were collected. According to the site of care, the highest AMR was observed in E. coli, K. pneumoniae, and P. aeruginosa isolates from ICU patients. In contrast, in A. baumannii, higher AMR was observed in isolates from hospitalized non-ICU patients. According to age group, the highest AMR was observed in the ≥60 years age group for E. coli, E. faecium, and S. aureus, and in the 19-59 years age group for A. baumannii and P. aeruginosa. According to clinical specimen type, a higher AMR was observed in E. coli, K. pneumoniae, and P. aeruginosa isolates from blood specimens. The most frequently detected carbapenemase-encoding gene in E. coli was blaNDM (84%).

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IL-9 is a pleiotropic cytokine associated with various processes, including antitumor immunity, induction of allergic pathologies, and the immune response against helminth infections, where it plays an important role in the expulsion of the parasite. In a murine model of Nippostrongylus brasiliensis infection, IL-9 is produced mainly by CD4+ T lymphocytes and innate lymphoid cells found in the lung, small intestine, and draining lymph nodes. Given the technical difficulties involved in the intracellular staining of IL-9, as well as the complexity of isolating hematopoietic cells from the small intestine upon infection, there is a pressing need for a comprehensive but straightforward protocol to analyze the expression of IL-9 in different lymphoid and non-lymphoid tissues in this model. The protocol described here outlines the kinetics of IL-9 produced by CD4+ T cells and innate lymphoid cells in the lung and small intestine, the main organs targeted by N. brasiliensis, as well as in the mediastinal and mesenteric lymph nodes, throughout the infection. In addition, it details the number of larvae needed for infection, depending on the cell type and organ of interest. This protocol aims to assist in the standardization of assays to save time and resources by offering the opportunity to focus on the specific cells, organs, and disease stages of interest in the N. brasiliensis infection model.

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BACKGROUND: Urinary tract infections (UTI) are one of the most common pathologies in Mexico and the majority are caused by uropathogenic Escherichia coli (UPEC). UPEC possesses virulence and resistance determinants that promote UTI development and affect diagnosis and treatment. This study aims to systematically review published reports of virulence genes, antibiotic resistance, and phylogenetic groups prevalent in clinical isolates of UPEC in the Mexican population. METHODS: Systematic review with meta-analysis was performed following PRISMA guidelines. Articles in both English and Spanish were included. Total prevalence with a 95% confidence interval of each characteristic was calculated. Heterogeneity between studies and geographical areas was assessed by the Cochran Q test (Q), I-square (I2), and H-square (H2). Egger's test was used for risk of bias in publications and asymmetry evaluations. RESULTS: Forty-two articles were analyzed. The most prevalent virulence genes were ecp (97.25%; n = 364) and fimH (82.34%; n = 1,422), which are associated with lower UTI, followed by papGII (40.98%; n = 810), fliC (38.87%; n = 319), hlyA (23.55%; n = 1,521), responsible for with upper UTI. More than 78.13% (n = 1,893) of the isolates were classified as multidrug-resistant, with a higher prevalence of resistance to those antibiotics that are implemented in the basic regimen in Mexico. The most frequently reported Extended Spectrum ß-Lactamase (ESBL) was CTX-M-1 (55.61%; n = 392), and the predominant phylogroup was B2 (35.94%; n = 1,725). CONCLUSION: UPEC strains are responsible for a large portion of both lower and upper UTI in Mexico, and their multi-drug resistance drastically reduces the number of therapeutic options available.

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