According to the World Health Organization (WHO), tuberculosis (TB) remains a significant global health challenge, with approximately 10 million new cases and 1.4 million deaths reported in 2020. TB disproportionately affects low- and middle-income countries, where factors such as migrant population, malnutrition, type 2 diabetes, human immunodeficiency virus (HIV) co-infection, and COVID-19 exacerbate its impact. TB also leads to substantial economic losses due to decreased productivity and high healthcare costs. Despite advances in treatments, TB remains a major public health issue, particularly in poorer regions. In Mexico, TB is considered a moderate-incidence disease, with higher prevalence in border states, mainly due to population displacements. Effective TB control requires collaboration between Mexico and the United States of America given the high cross-border human movement, like in the Baja California State that reported predominantly pulmonary TB cases. Effective management of TB involves rapid diagnosis and identification of antibiotic resistance. Techniques such as PCR, high-resolution computed tomography (HRCT), and/or Xpert MTB/RIF have enhanced diagnostic accuracy. Future perspectives about TB management focus on developing new drugs and vaccines to combat drug-resistant strains, and the comorbidities associated, which must be addressed to reinforce of health public programs.

Escherichia coli is an opportunistic pathogen and a leading cause of Community-Acquired Urinary Tract Infections (CA-UTIs). E. coli can harbor multiple genetic resistant determinants, such as Extended Spectrum Beta-lactamases (ESBL) and Plasmid-Mediated Quinolone Resistance (PMQR) genes, complicating the empirical treatment of UTIs with β-lactams and quinolones. The aim of his study was to characterize ESBL and PMQR genes among E. coli isolates from CA-UTI in Mexicali, Mexico Isolates were collected from January to December 2023. Identification was performed by MALDI-TOF, and ESBL-producing determination and antimicrobial susceptibility by Vitek 2. Detection of ESBL and PMQR, and phylotyping were performed by PCR. Genetic diversity was determined by Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC-PCR). Eighty-nine E. coli isolates were collected from CA-UTIs. All exhibited resistance to ciprofloxacin, ceftriaxone, and cefotaxime, while being susceptible to carbapenems and ceftazidime/avibactam. All isolates tested positive for an ESBL gene, with bla_CTX-M (98.9 %) being the most prevalent. Five isolates tested negative for PMQR genes; the remaining showed aac(6')-lb-cr present in 85.3 %. Coexistence between ESBL and PMQR genes was noted in 95.5 %. Most prevalent plylogenetic group was group B2 (74.2 %). This study provides valuable regional data, highlighting a public health problem due to the high prevalence of ESBL and PMQR genes in E. coli responsible for CA-UTI, which are linked to multidrug resistance. Genetic diversity was found, suggesting multiple sources of resistant strains in the community. These findings underline the need for surveillance and control to limit the spread of resistant E. coli, locally and globally. DATA SUMMARY: The authors confirm all supporting data, code, and protocols have been provided within the article or through supplementary data files.

The goal of this study was to determine the most common microorganisms present in COVID-19 patients with co-infections at the General Hospital of Mexicali. Bacterial co-infections have been reported in two previous global pandemics caused by viruses. In a retrospective observational study, we obtained information from 1979 patients. All had symptoms of respiratory disease, and we performed real-time Polymerase Chain Reaction tests on nasopharyngeal swab samples. Of the 1979 patients, 316 were negative; so, they were excluded. One thousand and sixty-three patients had positive results for COVID-19; one hundred and seventy-two (10.34%) had respiratory co-infections. These data were corroborated by positive growth results in culture media and identified using the MALDI-TOF MS System. Vitek 2^® Compact, an automated identification system, determined the antimicrobial susceptibility testing results. We analyzed and determined the microorganisms in co-infected patients. Different microorganisms were found, including bacteria and fungi. The most prevalent of all the organisms was Acinetobacter baumannii, which was present in 64 patients (37.2%). We recommend improving the diagnostic and surveillance protocols for possible cases of co-infections in patients with COVID-19. Unlike co-infections in pandemic influenza, the spectrum of microorganisms that cause COVID-19 is too broad and varied to recommend empiric antibiotic therapy.

The canonical Wnt signaling pathway is a master cell regulator involved in CD8⁺ T cell proliferation and differentiation. In human CD8⁺ T cells, this pathway induces differentiation into memory cells or a “stem cell memory like” population, which is preferentially present in cord blood. To better understand the role of canonical Wnt signals in neonatal or adult blood, we compared the proteins associated with β‐catenin, in nonstimulated and Wnt3a‐stimulated human neonatal and adult naive CD8⁺ T cells. Differentially recruited proteins established different complexes in adult and neonatal cells. In the former, β‐catenin‐associated proteins were linked to cell signaling and immunological functions, whereas those of neonates were linked to proliferation and metabolism. Wnt3a stimulation led to the recruitment and overexpression of Wnt11 in adult cells and Wnt5a in neonatal cells, suggesting a differential connexion with planar polarity and Wnt/Ca²⁺ noncanonical pathways, respectively. The chromatin immunoprecipitation polymerase chain reaction β‐catenin was recruited to a higher level on the promoters of cell renewal genes in neonatal cells and of differentiation genes in those of adults. We found a preferential association of β‐catenin with CBP in neonatal cells and with p300 in the adult samples, which could be involved in a higher self‐renewal capacity of the neonatal cells and memory commitment in those of adults. Altogether, our results show that different proteins associated with β‐catenin during Wnt3a activation mediate a differential response of neonatal and adult human CD8⁺ T cells.

Determinar la sensibilidad de la técnica de reacción en cadena de polimerasa: BIOFIRE® FILMARRAY® Pneumonia Panel plus (FA-pneumo) de BIOMÉRIEUX en comparación con los cultivos tradicionales en aislados de pacientes hospitalizados en la ciudad de Mexicali. Se colectaron muestras en 5 hospitales de Mexicali y fueron enviadas para su identificación al Laboratorio Dorado para su identificación. Fueron procesadas 105 muestras aisladas de pacientes con sospecha de neumonía mediante cultivos microbiológicos convencionales y el ensayo FA-pneumo. Se detectaron 19 bacterias simultáneamente en el cultivo y en el FA-pneumo. Se identificaron 31 bacterias exclusivamente con el FA-pneumo y no desarrollaron crecimiento en el cultivo. Únicamente 4 bacterias se desarrollaron en el cultivo, pero mediante el FA-pneumo no se detectó. El FA-Pneumo presentó mayor sensibilidad en comparación con el cultivo convencional, enfatizando que FA-Pneumo analiza la información genética de bacterias y virus, además de contar con la ventaja de generar un resultado cuantitativo, siendo de gran ayuda para correlacionar clínicamente si el paciente se encuentra colonizado o infectado. La principal ventaja de esta técnica y en especial para los médicos de cuidados intensivos es la rapidez del diagnóstico de esta técnica. En un tiempo promedio de 2 horas se logra la identificación de los agentes causales de la neumonía causadas por agentes infecciosos.

Pseudomonas aeruginosa is a Gram-negative bacillus capable of developing in humid environments and animal tissue. The interest in this bacterium lies in its ability to cause opportunistic diseases in patients with cystic fibrosis and healthcare-associated infections (HAIs). The objective of our study was to characterize the resistance profile of strains causing HAIs isolated in hospitals within our community, from January 2019 to December 2021. This descriptive, prospective, and cross-sectional study involved the isolation of strains from January 2019 to December 2021 at the Autonomous University of Baja California (UABC). The identification of the strains was carried out using Matrix-Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) mass spectrometry, and the detection of beta-lactam resistance was performed according to the criteria of the Clinical and Laboratory Standards Institute as stipulated in the CLSI M100-S27 document. A total of 649 samples were obtained from January 2019 to December 2021, including sputum (335 samples), urine (119 samples), and wounds (91 samples). Resistance to carbapenems was 38.94% for meropenem and 21.97% for imipenem. For cephalosporins, there was a 21.05% resistance rate for cefepime, 22.9% for ceftazidime, and 24.78% for ceftolozane-tazobactam. The prevalence of antimicrobial resistance has increased over time, which is attributable to both selective pressure and the evolution of the microorganisms themselves. (c) 2024 The Author(s). Published by Elsevier Espana, S.L.U. on behalf of Asociacion Argentina de Microbiolog& imath;a. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).