Urinary tract infections (UTIs) are mainly caused by uropathogenic
Escherichia coli
(UPEC), whose impact can be exacerbated by multidrug-resistant (MDR) strains. Effective control strategies are, ...therefore, urgently needed. Among them, phage therapy represents a suitable alternative. Here, we describe the isolation and characterization of novel phages from wastewater samples, as well as their lytic activity against biofilm and adherence of UPEC to HEp-2 cells. The results demonstrated that phage vB_EcoM-phiEc1 (ϕEc1) belongs to
Myoviridae
family, whereas vB_EcoS-phiEc3 (ϕEc3) and vB_EcoS-phiEc4 (ϕEc4) belong to
Siphoviridae
family. Phages showed lytic activity against UPEC and gut commensal strains. Phage ϕEc1 lysed UPEC serogroups, whereas phages ϕEc3 and ϕEc4 lysed only UTI strains with higher prevalence toward the O25 serogroup. Moreover, phages ϕEc1 and ϕEc3 decreased both biofilm formation and adherence, whereas ϕEc4 was able to decrease adherence but not biofilm formation. In conclusion, these novel phages showed the ability to decrease biofilm and bacterial adherence, making them promising candidates for effective adjuvant treatment against UTIs caused by MDR UPEC strains.
Key points
Phage with lytic activity against MDR UPEC strains were isolated and characterized under in vitro conditions.
A novel method was proposed to evaluate phage activity against bacterial adherence in HEp-2 cell.
.
Phages represent a suitable strategy to control infections caused by MDR bacteria
.
Among the diseases transmitted by vectors, there are those caused by viruses named arboviruses (arthropod-borne viruses). In past years, viruses transmitted by mosquitoes have been of relevance in ...global health, such as Chikungunya (CHIKV), Dengue (DENV), and Zika (ZIKV), which have
Aedes aegypti
as a common vector, thus raising the possibility of multi-infection. Previous reports have described the general structure of RNA-dependent RNA polymerases termed right-hand fold, which is conserved in positive single-stranded RNA viruses. Here, we report a comparison between sequences and the computational structure of RNA-dependent RNA polymerases from CHIKV, DENV, and ZIKV and the conserved sites to be considered for the design of an antiviral drug against the three viruses. We show that the sequential identity between consensus sequences from CHIKV and DENV is 8.1% and the similarity is 15.1%; the identity between CHIKV and ZIKV is 9.3%, and the similarity is 16.6%; and the identity between DENV and ZIKV is 68.6%, and the similarity is 79.2%. Nevertheless, the structural alignment shows that the root-mean-square deviation (RMSD) measurement value in general structure comparison between CHIKV RdRp and ZIKV RdRp was 1.248 Å, RMSD between CHIKV RdRp and DENV RdRp was 1.070 Å, and RMSD between ZIKV RdRp and DENV RdRp was 1.106 Å. Despite the low identity and similarity of CHIKV sequence with DENV and ZIKV, we show that A, B, C, and E motifs are structurally well conserved. These structural similarities offer a window into drug design against these arboviruses giving clues about critical target sites.
is a global public health problem, which is a primary cause of antibiotic-associated diarrhea in humans. The emergence of hypervirulent and antibiotic-resistant strains is associated with the ...increased incidence and severity of the disease. There are limited studies on genomic characterization of
in Latin America. We aimed to learn about the molecular epidemiology and antimicrobial resistance in
strains from adults and children in hospitals of México. We studied 94
isolates from seven hospitals in Mexico City from 2014 to 2018. Whole-genome sequencing (WGS) was used to determine the genotype and examine the toxigenic profiles. Susceptibility to antibiotics was determined by
-test. Multilocus sequence typing (MLST) was used to determine allelic profiles. Results identified 20 different sequence types (ST) in the 94 isolates, mostly clade 2 and clade 1. ST1 was predominant in isolates from adult and children. Toxigenic strains comprised 87.2% of the isolates that were combinations of
and
(
, followed by
,
-/
, and
/
). Toxin profiles were more diverse in isolates from children. All 94 isolates were susceptible to metronidazole and vancomycin, whereas a considerable number of isolates were resistant to clindamycin, fluroquinolones, rifampicin, meropenem, and linezolid. Multidrug-resistant isolates (≥3 antibiotics) comprised 65% of the isolates. The correlation between resistant genotypes and phenotypes was evaluated by the kappa test. Mutations in
and
showed moderate concordance with resistance to rifampicin and mutations in
substantial concordance with fusidic acid resistance.
, a gene recently described in one Mexican isolate, was present in 65% of strains linezolid resistant, all ST1 organisms. WGS is a powerful tool to genotype and characterize virulence and antibiotic susceptibility patterns.
Zika virus (ZIKV) is an emerging flavivirus that represents significant public health challenges, particularly in the Americas, and is a substantial risk to other parts of the world due to its rapid ...expansion and its established association with neurological disorders, including Guillain–Barré syndrome and an intrauterine fetal infection that can cause microcephaly, blindness, and other congenital neurological complications. To date, no vaccine to prevent ZIKV infections has been approved. Therefore, developing a safe and effective vaccine against this virus is a global health priority. This review analyzes the ZIKV outbreaks, as well as associated neurological complications, its genome, and immunological responses. The current vaccines in development have reported results from preclinical and clinical trials about novel approaches to obtain safer and more effective vaccines and the challenges faced by ZIKV vaccine development.
Tuberculosis is a disease caused by
, representing the second leading cause of death by an infectious agent worldwide. The available vaccine against this disease has insufficient coverage and ...variable efficacy, accounting for a high number of cases worldwide. In fact, an estimated third of the world's population has a latent infection. Therefore, developing new vaccines is crucial to preventing it. In this study, the highly antigenic PE_PGRS49 and PE_PGRS56 proteins were analyzed. These proteins were used for predicting T- and B-cell epitopes and for human leukocyte antigen (HLA) protein binding efficiency. Epitopes GGAGGNGSLSS, FAGAGGQGGLGG, GIGGGTQSATGLG (PE_PGRS49), and GTGWNGGKGDTG (PE_PGRS56) were selected based on their best physicochemical, antigenic, non-allergenic, and non-toxic properties and coupled to HLA I and HLA II structures for in silico assays. A construct with an adjuvant (RS09) plus each epitope joined by GPGPG linkers was designed, and the stability of the HLA-coupled construct was further evaluated by molecular dynamics simulations. Although experimental and in vivo studies are still necessary to ensure its protective effect against the disease, this study shows that the vaccine construct is dynamically stable and potentially effective against tuberculosis.
•Vascular endothelial growth factor.•Pediatric hematopoietic stem cell transplantation.•Real-time Polymerase Chain Reaction.
Vascular endothelial growth factors are proteins that participate in ...processes related to normal physiology, solid tumors and hematologic malignancies; however, their role in hematopoietic stem cell transplantation (HSCT) requires further investigation. To better define the role and changes in vascular endothelial growth factor-A (VEGF-A) in the context of HSCT, we conducted an observational prospective analysis of VEGF-A expression during the early period after HSCT in pediatric patients. Thirty-seven pediatric patients who underwent hematopoietic stem cell transplantation at the Federico Gómez Children's Hospital in Mexico between June 2016 and July 2018 were prospectively enrolled in this study. Ribonucleic acid was isolated from the venous blood of these patents on Days 0, +7, +14, +21, +28, and +35 after transplantation, and TaqMan reverse transcription-polymerase chain reaction was performed using specific primers and a probe for VEGF-A. The concentration of VEGF-A was determined using a complementary deoxyribonucleic acid control. Data were analyzed using one-way ANOVA and Dunnett post hoc tests. Statistical analysis was performed using SPSS version 25. There were significant differences in the concentrations of VEGF-A between Day 0 vs. Day +28 (p = 0.009 95% CI=0.02–0.24), Day 0 vs. Day +35 (p = 0.006; 95% CI=0.03–0.28) and Day 7 vs. Day + 35 (p = 0.006; 95% CI=0.03–0.24) after allogeneic HSCT. We observed significant increases in the VEGF-A concentration during the early period after stem cell transplantation in pediatric patients. Our results provide important insights that should be considered a basis for future clinical trials of pediatric HSCT, including the monitoring of VEGF-A concentrations, proteins and in vitro analysis.
Background. Urinary tract infections (UTIs) are a public health problem in Mexico, and uropathogenic Escherichia coli (UPEC) is one of the main etiological agents. Flagella, type I fimbriae, and ...curli promote the ability of these bacteria to successfully colonize its host. Aim. This study aimed to determine whether flagella-, type I fimbriae-, and curli-expressing UPEC induces the release of proinflammatory cytokines in an established coculture system. Methods. The fliC, fimH, and csgA genes by UPEC strain were disrupted by allelic replacement. Flagella, type I fimbriae, and curli were visualized by transmission electron microscopy (TEM). HTB-5 (upper chamber) and HMC-1 (lower chamber) cells cocultured in Transwell® plates were infected with these UPEC strains and purified proteins. There was adherence to HTB-5 cells treated with different UPEC strains and they were quantified as colony-forming units (CFU)/mL. Results. High concentrations of IL-6 and IL-8 were induced by the FimH and FliC proteins; however, these cytokines were detected in low concentrations in presence of CsgA. Compared with UPEC CFT073, CFT073ΔfimH, CFT073ΔfimHΔfliC, and CFT073ΔcsgAΔfimH strains significantly reduced the adherence to HTB-5 cells. Conclusion. The FimH and FliC proteins are involved in IL-6 and IL-8 release in a coculture model of HTB-5 and HMC-1 cells.
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•The main protease of SARS-CoV-2 has a highly flexible active site.•Drug repurposing is a treatment opportunity in the current COVID-19 pandemic.•Nine drugs merit testing as ...inhibitors of the SARS-CoV-2 main protease.
The global emergency caused by COVID-19 makes the discovery of drugs capable of inhibiting SARS-CoV-2 a priority, to reduce the mortality and morbidity of this disease. Repurposing approved drugs can provide therapeutic alternatives that promise rapid and ample coverage because they have a documented safety record, as well as infrastructure for large-scale production. The main protease of SARS-CoV-2 (Mpro) is an excellent therapeutic target because it is critical for viral replication; however, Mpro has a highly flexible active site that must be considered when performing computer-assisted drug discovery. In this work, potential inhibitors of the main protease (Mpro) of SARS-Cov-2 were identified through a docking-assisted virtual screening procedure. A total of 4384 drugs, all approved for human use, were screened against three conformers of Mpro. The ligands were further studied through molecular dynamics simulations and binding free energy analysis. A total of nine currently approved molecules are proposed as potential inhibitors of SARS-CoV-2. These molecules can be further tested to speed the development of therapeutics against COVID-19.
Relapse occurs in approximately 20% of Mexican patients with childhood acute lymphoblastic leukemia (ALL). In this group, chemoresistance may be one of the biggest challenges. An overview of complex ...cellular processes like drug tolerance can be achieved with proteomic studies.
The B-lineage pediatric ALL cell line CCRF-SB was gradually exposed to the chemotherapeutic vincristine until proliferation was observed at 6nM, control cells were cultured in the absence of vincristine. The proteome from each group was analyzed by nanoHPLC coupled to an ESI-ion trap mass spectrometer. The identified proteins were grouped into overrepresented functional categories with the PANTHER classification system.
We found 135 proteins exclusively expressed in the presence of vincristine. The most represented functional categories were: Toll receptor signaling pathway, Ras Pathway, B and T cell activation, CCKR signaling map, cytokine-mediated signaling pathway, and oxidative phosphorylation.
Our study indicates that signal transduction and mitochondrial ATP production are essential during adaptation of leukemic cells to vincristine, these processes represent potential therapeutic targets.
Aproximadamente el 20% de los pacientes mexicanos con leucemia linfoblástica aguda (LLA) infantil presentan recaídas. En este grupo, la quimiorresistencia es uno de los principales desafíos. Los estudios proteómicos pueden dar un panorama general de procesos celulares complejos como la tolerancia a fármacos.
La línea celular de LLA de linaje B, CCRF-SB, fue expuesta de manera gradual al fármaco quimioterapéutico vincristina hasta observar proliferación celular en presencia de 6nM, como control se cultivaron células en ausencia del fármaco. Se analizó el proteoma de cada grupo mediante nanoHPLC acoplado a un espectrómetro de masas de tipo trampa de iones. Las proteínas identificadas se agruparon en categorías funcionales sobre-representadas con el sistema de clasificación PANTHER.
Encontramos 135 proteínas expresadas exclusivamente en presencia de vincristina. Las categorías funcionales más representadas fueron la señalización asociada a los receptores tipo Toll, señalización dependiente de Ras, activación de células B y T, mapa de señalización CCKR, señalización mediada por citoquinas y la fosforilación oxidativa.
Nuestro estudio indica que la transducción de señales y la producción de ATP mitocondrial son procesos esenciales durante la adaptación de células leucémicas a vincristina por lo que estos procesos representan potenciales blancos terapéuticos.
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