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1.
Reprod Biol ; 22(1): 100604, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35033900

RESUMEN

Intrauterine infections caused by bacteria like group B streptococcus (GBS) and the subsequent activation of the maternal inflammatory response have been long suspected to be the underlying cause of preterm labor. The inflammatory network triggered by maternal decidua has been widely described and includes the secretion of pro- and anti-inflammatory cytokines as IL-1ß and IL-10; however, the mechanisms that regulate their secretion have not been completely elucidated. MicroRNAs (miRNAs) are critical modulators of the inflammatory response by regulating cytokine expression in several cell types. Here, we explored the role of miR-21 in the expression of IL-1ß and IL-10 in human decidual stromal cells (DSCs) exposed in vitro to GBS. We observed that IL1B and IL10 expression at the mRNA level was increased in DSCs after GBS infection. IL-10 but not IL-1ß secretion was detected in the culture supernatants. We found a higher miR-21 expression (22-fold) in infected DSCs as compared with non-infected cells. miR-21 functional analysis revealed that DSCs transfected with an antagomiR vs. miR-21 significantly increased the secretion of IL-1ß but decreased that of IL-10 in DSCs cells infected with GBS. Our results suggest that miR-21 participates in balancing the inflammatory response in infected decidua through at least IL-1ß and IL-10 regulation. This is the first study attributing a functional role of miR-21 in the regulation of key molecules involved in the inflammatory response in infected DSCs, providing new insights into the epigenetic control of human decidual inflammation.


Asunto(s)
Decidua/citología , Interleucina-10 , Interleucina-1beta , MicroARNs , Células Cultivadas , Decidua/metabolismo , Femenino , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Streptococcus , Células del Estroma/metabolismo
2.
J Oncol ; 2021: 5528378, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34567117

RESUMEN

NK cells represent a heterogeneous subpopulation of lymphocytes of the innate immune system, which possess powerful antitumor activity. NK cells exhibit their function through a complex collection of receptors that act synergistically to recognize, regulate, or amplify the immune response. TLRs allow cells to detect PAMPs, MAMPs, or DAMPs, which are essential for the initiation of the immune response. Studies on the different subpopulations of NK cells and their expression profile of innate immune receptors in hematological cancers are limited. In this study, the specific subpopulations of NK cells in pediatric patients with acute lymphoblastic leukemia (ALL) and the repertoire and level of expression of TLRs in cytotoxic NK cells were assessed. The results suggested that pediatric patients with ALL exhibited a significant decrease in NK cells in peripheral blood and bone marrow, in addition to alterations in the distribution of the subpopulations of cells. Regulatory and cytotoxic NK cells were diminished, whereas dysfunctional phenotype was considerably increased. Cytotoxic NK cells from children with ALL expressed all 10 TLRs, and expression of TLR1 and TLR9 was decreased compared with the controls. Interestingly, cytotoxic NK cells exhibited a higher expression of TLR1 in the bone marrow than in the peripheral blood of patients with ALL. The present study is the first to show that TLR10 was expressed in the cytotoxic NK cells and the first to assess the profile and levels of the 10 known TLRs in cytotoxic NK cells from patients with ALL. The alterations in expression levels and cellular distribution may be involved in the immune response.

3.
Front Microbiol ; 12: 611274, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33841344

RESUMEN

Nosocomial infections caused by multidrug-resistant (MDR) Klebsiella pneumoniae are a major health problem worldwide. The aim of this study was to describe NDM-1-producing K. pneumoniae strains causing bacteremia in a tertiary referral hospital in Mexico. MDR K. pneumoniae isolates were screened by polymerase chain reaction for the presence of resistance genes. In resistant isolates, plasmids were identified and conjugation assays were performed. Clonal diversity and the sequence types were determined by pulsed-field gel electrophoresis and multilocus sequence typing. A total of 80 K. pneumoniae isolates were collected from patients with bacteremia over a 1-year period. These isolates showed a level of resistance of 59% (47/80) to aztreonam, 56-60% (45-48/80) to cephalosporins, 54% (43/80) to colistin and 12.5% (10/80) to carbapenems. The carbapenem resistant isolates were bla NDM- 1 carriers and negative for bla KPC, bla NDM, bla IMP, bla VIM and bla OXA- 48 -like carbapenemases genes. Conjugative plasmids IncFIIA and IncF group with sizes of 82-195 kbp were carriers of bla NDM- 1, bla CTX-M- 15, bla TEM- 1, aac(6')-Ib and/or aac(3')-IIa. Clonal variability and nine different multilocus sequence types were detected (ST661, ST683, ST1395, ST2706, ST252, ST1198, ST690, ST1535, and ST3368) for the first time in the isolates carrying bla NDM- 1 in Mexico. This study demonstrates that bla NDM- 1 has remained within this hospital in recent years and suggests that it is currently the most prevalent carbapenemase among K. pneumoniae MDR strains causing bacteremia in Mexico. The horizontal transfer of bla NDM- 1 gene through IncF-like plasmids among different clones demonstrates the dissemination pathway of antimicrobial resistance and underscore the need for strong and urgent joint measures to control the spread of NDM-1 carbapenemase in the hospital.

4.
Parasitol Res ; 120(3): 1067-1076, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33515065

RESUMEN

Giardia intestinalis is a human parasite that causes a diarrheal disease in developing countries. G. intestinalis has a cytoskeleton (CSK) composed of microtubules and microfilaments, and the Giardia genome does not code for the canonical CSK-binding proteins described in other eukaryotic cells. To identify candidate actin and tubulin cross-linking proteins, we performed a BLAST analysis of the Giardia genome using a spectraplakins consensus sequence as a query. Based on the highest BLAST score, we selected a 259-kDa sequence designated as a cytoskeleton linker protein (CLP259). The sequence was cloned in three fragments and characterized by immunoprecipitation, confocal microscopy, and mass spectrometry (MS). CLP259 was located in the cytoplasm in the form of clusters of thick rods and colocalized with actin at numerous sites and with tubulin in the median body. Immunoprecipitation followed by mass spectrometry revealed that CLP259 interacts with structural proteins such as giardins, SALP-1, axonemal, and eight coiled-coils. The vesicular traffic proteins detected were Mu adaptin, Vacuolar ATP synthase subunit B, Bip, Sec61 alpha, NSF, AP complex subunit beta, and dynamin. These results indicate that CLP259 in trophozoites is a CSK linker protein for actin and tubulin and could act as a scaffold protein driving vesicular traffic.


Asunto(s)
Actinas/metabolismo , Giardia lamblia/metabolismo , Plaquinas/metabolismo , Tubulina (Proteína)/metabolismo , Actinas/química , Secuencia de Aminoácidos , Animales , Ancirinas/química , Secuencia de Bases , Western Blotting , Biología Computacional , Secuencia de Consenso , Citoplasma/química , Citoesqueleto/química , Citoesqueleto/fisiología , Citoesqueleto/ultraestructura , Dinaminas/análisis , Femenino , Técnica del Anticuerpo Fluorescente , Giardia lamblia/química , Giardia lamblia/ultraestructura , Humanos , Inmunoprecipitación , Ratones , Ratones Endogámicos BALB C , Microscopía Confocal , Plaquinas/química , Alineación de Secuencia , Tubulina (Proteína)/química
5.
Gac Med Mex ; 156(2): 171-178, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32285851

RESUMEN

The World Health Organization estimates that bacterial resistance will cause 10 million deaths by 2050. As part of the Global Action Plan on Antimicrobial Resistance, it proposed networks of specialized laboratories in order to preserve strains and optimize the use of antimicrobials. That is the case of the Latin American Surveillance Network of Antimicrobials Resistance. In a 2019 study, the main bacteria of the ESKAPE group (which are highly resistant to the most widely used antibiotics) that cause infections in Mexican Hospitals were identified to be multidrug-resistant (MDR) and extended-spectrum beta-lactamase (ESBL)-producing Klebsiella spp., ESBL-producing Enterobacter spp., Acinetobacter baumannii, MDR Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium. With information on drug resistance, regimens are recommended to treat infection caused by Helicobacter pylori, a pathogen related to the development of cancer and whose prevalence in the adult population of Latin America is estimated to range between 60 and 70 %.


La Organización Mundial de la Salud estima que en 2050 la resistencia bacteriana ocasionará 10 millones de muertes. Como parte del Plan de Acción Mundial sobre la Resistencia a los Antimicrobianos propuso redes de laboratorios especializados, para conservar cepas y optimizar el uso de los antimicrobianos. En un estudio de 2019 se identificó que las principales bacterias del grupo ESKAPE (con alta resistencia a los antibióticos más usados) que causan infecciones en hospitales de México son Klebsiella spp. resistentes a múltiples fármacos (MDR) y productoras de betalactamasa de espectro extendido (BLEE), Enterobacter spp. BLEE, Acinetobacter baumannii, Pseudomonas aeruginosa MDR, Staphylococcus aureus meticilinorresistente y Enterococcus faecium resistente a vancomicina. Con la información de resistencia a los fármacos se recomiendan esquemas para tratar la infección causada por Helicobacter pylori, relacionado con el desarrollo de cáncer y cuya prevalencia en la población adulta de Latinoamérica se estima es de entre 60 y 70 %.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/epidemiología , Resistencia a Múltiples Medicamentos , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/prevención & control , Humanos , América Latina/epidemiología
6.
Gac. méd. Méx ; 156(2): 172-180, mar.-abr. 2020.
Artículo en Inglés, Español | LILACS | ID: biblio-1249889

RESUMEN

Resumen La Organización Mundial de la Salud estima que en 2050 la resistencia bacteriana ocasionará 10 millones de muertes. Como parte del Plan de Acción Mundial sobre la Resistencia a los Antimicrobianos propuso redes de laboratorios especializados, para conservar cepas y optimizar el uso de los antimicrobianos. En un estudio de 2019 se identificó que las principales bacterias del grupo ESKAPE (con alta resistencia a los antibióticos más usados) que causan infecciones en hospitales de México son Klebsiella spp. resistentes a múltiples fármacos (MDR) y productoras de betalactamasa de espectro extendido (BLEE), Enterobacter spp. BLEE, Acinetobacter baumannii, Pseudomonas aeruginosa MDR, Staphylococcus aureus meticilinorresistente y Enterococcus faecium resistente a vancomicina. Con la información de resistencia a los fármacos se recomiendan esquemas para tratar la infección causada por Helicobacter pylori, relacionado con el desarrollo de cáncer y cuya prevalencia en la población adulta de Latinoamérica se estima es de entre 60 y 70 %.


Abstract The World Health Organization estimates that bacterial resistance will cause 10 million deaths by 2050. As part of the Global Action Plan on Antimicrobial Resistance, it proposed networks of specialized laboratories in order to preserve strains and optimize the use of antimicrobials. In a 2019 study, the main bacteria of the ESKAPE group (which are highly-resistant to the most widely used antibiotics) that cause infections in Mexican hospitals were identified to be multidrug-resistant (MDR) and extended spectrum beta-lactamase (ESBL)-producing Klebsiella spp., ESBL-producing Enterobacter spp., Acinetobacter baumannii, MDR Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium. With information on drug resistance, regimens are recommended to treat infection caused by Helicobacter pylori, a pathogen related to the development of cancer and whose prevalence in the adult population of Latin America is estimated to range between 60 and 70%.


Asunto(s)
Humanos , Infecciones Bacterianas/epidemiología , Resistencia a Múltiples Medicamentos , Antibacterianos/uso terapéutico , Infecciones Bacterianas/prevención & control , Infecciones Bacterianas/tratamiento farmacológico , América Latina/epidemiología
7.
Front Cell Infect Microbiol ; 10: 539115, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33643927

RESUMEN

Helicobacter pylori strains carry a range of mutations in genes that confer antimicrobial resistance and restrict the available options to treat the infection. Latin America is a region that conserve a large number of indigenous communities relatively isolated that practice a traditional medicine without consumption of drugs. We hypothesized that rates of antibiotic resistance are lower in these communities. Recent progress in whole-genome sequencing has allowed the study of drug susceptibility by searching for the known mutations associated with antibiotic resistance. The aim of this work was to study trends of antibiotic resistance over a 20-year period in Mexican H. pylori strains and to compare susceptibility between strains from Mexican mestizos and from indigenous population; we also aimed to learn the prevalence of mutational patterns in genes gyrA, gyrB, rdxA, frxA, rpsU, omp11, dppA, and 23S rRNA and its association with phenotypic tests. Resistance to clarithromycin, metronidazole, amoxicillin and levofloxacin was determined in167 H. pylori isolates by E-test, and the occurrence of mutational patterns in specific genes was determined by whole genome sequencing (WGS). The trend of resistance over 20 years in mestizo isolates showed significant resistant increase for clarithromycin and levofloxacin to frequencies that banned its clinical use. Resistance in H. pylori isolates of native communities was lower for all antibiotics tested. Phenotypic resistance showed good to moderate correlation with genotypic tests. Genetic methods for characterizing antibiotic resistance require further validation in each population.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Farmacorresistencia Microbiana , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/genética , Humanos , México , Pruebas de Sensibilidad Microbiana
8.
Front Microbiol ; 10: 2116, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31616391

RESUMEN

Acinetobacter baumannii is one of the most important nosocomial pathogens distributed worldwide. Due to its multidrug-resistance and the propensity for the epidemic spread, the World Health Organization includes this bacterium as a priority health issue for development of new antibiotics. The aims of this study were to investigate the antimicrobial resistance profile, the clonal relatedness, the virulence profiles, the innate host immune response and the clonal dissemination of A. baumannii in Hospital Civil de Guadalajara (HCG), Hospital Regional General Ignacio Zaragoza (HRGIZ) and Pediatric ward of the Hospital General de México Eduardo Liceaga (HGM-P). A total of 252 A. baumannii clinical isolates were collected from patients with nosocomial infections in these hospitals between 2015 and 2016. These isolates showed a multidrug-resistant profile and most of them only susceptible to colistin. Furthermore, 83.3 and 36.9% of the isolates carried the bla OXA- 24 and bla TEM- 1 genes for resistance to carbapenems and ß-lactam antibiotics, respectively. The clonal relatedness assessed by pulsed-field gel electrophoresis (PFGE) and by multi-locus sequence typing (MLST) demonstrated a genetic diversity. Remarkably, the ST136, ST208 and ST369 that belonged to the clonal complex CC92 and ST758 and ST1054 to the CC636 clonal complex were identified. The ST136 was a high-risk persistent clone involved in an outbreak at HCG and ST369 were related to the first carbapenem-resistant A. baumannii outbreak in HRGIZ. Up to 58% isolates were able to attach to A549 epithelial cells and 14.5% of them induced >50% of cytotoxicity. A549 cells infected with A. baumannii produced TNFα, IL-6 and IL-1ß and the oxygen and nitrogen reactive species that contributes to the development of an inflammatory immune response. Up to 91.3% of clinical isolates were resistant to normal human serum activity. Finally, 98.5% of the clinical isolates were able to form biofilm over polystyrene tubes. In summary, these results demonstrate the increasingly dissemination of multidrug-resistant A. baumannii clones in three hospitals in Mexico carrying diverse bacterial virulence factors that could contribute to establishment of the innate immune response associated to the fatality risks in seriously ill patients.

9.
Microb Drug Resist ; 25(6): 830-838, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30835632

RESUMEN

The emergence of New Delhi metallo-ß-lactamase 1 on carbapenemase-producing bacteria has raised a major worldwide public health concern. This study reports the dissemination of blaNDM-1 in carbapenem-resistant isolates that caused nosocomial infections in a tertiary hospital in Mexico City. Seven Enterobacter cloacae and three Klebsiella pneumoniae nosocomial isolates from the same time period harbored the blaNDM-1 gene. The resistance phenotype and the blaNDM-1 gene were transferred through conjugative plasmids belonging to the incompatibility group IncFIA of 85, 101, and 195 kb in E. cloacae and 95 and 101 kb in K. pneumoniae isolates. Restriction fragment length polymorphism analysis showed that blaNDM-1 was carried in similar plasmids with molecular sizes of 101 and 85 kb, each one in three isolates of E. cloacae and one of 101 kb on two isolates of K. pneumoniae. During a 9-month period, six of the seven isolates of E. cloacae analyzed harbored blaNDM-1 and belonged to clone E1. Similarly, over a 5-month period, two of the three K. pneumoniae isolates that harbored blaNDM-1 belonged to clone K1. These results demonstrate the horizontal transfer of blaNDM-1 between different bacterial species, dissemination of clones with high levels of resistance to carbapenems, and underscore the need for heightened measures to control their further spread.


Asunto(s)
Proteínas Bacterianas/genética , Enterobacter cloacae/genética , Enterobacter cloacae/aislamiento & purificación , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Plásmidos/genética , beta-Lactamasas/genética , Antibacterianos/farmacología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple/genética , Enterobacter cloacae/efectos de los fármacos , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Infecciones por Enterobacteriaceae/microbiología , Humanos , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , México , Pruebas de Sensibilidad Microbiana/métodos , Centros de Atención Terciaria
11.
BMC Cancer ; 17(1): 384, 2017 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-28558708

RESUMEN

BACKGROUND: Gastric adenocarcinoma is the third most common cause of cancer-associated death worldwide. Helicobacter pylori infection activates a signaling cascade that induces production of cytokines and chemokines involved in the chronic inflammatory response that drives carcinogenesis. We evaluated circulating cytokines and chemokines as potential diagnostic biomarkers for gastric cancer. METHODS: We included 201 healthy controls and 162 patients with distal gastric cancer who underwent primary surgical resection between 2009 and 2012 in Mexico City. The clinical and pathological data of patients were recorded by questionnaire, and the cancer subtype was classified as intestinal or diffuse. Pathological staging of cancer was based on the tumor-node-metastasis staging system of the International Union Against Cancer. Concentrations of IL-1ß, IL-6, TNF-α, IL-10, and MCP-1 in serum were measured using multiplex analyte profiling technology and concentrations of IL-8, IFN-γ, and TGF-ß in plasma were measured using enzyme-linked immunosorbent assay. RESULTS: Levels of IL-1ß, IL-6, IFN-γ, and IL-10 were significantly higher and that of MCP-1 was lower in gastric cancer patients compared with controls. No differences in IL-8 or TNF-α levels were observed between gastric cancer and controls. IFN-γ and IL-10 were significantly higher in both intestinal and diffuse gastric cancer, whereas IL-1ß and IL-6 were higher and TGF-ß lower only in intestinal gastric cancer; MCP-1 was lower only in diffuse gastric cancer. IFN-γ and IL-10 levels were significantly higher in early (I/II) and late stage (III/IV) gastric cancer; IL-1ß and IL-8 were higher and MCP-1 was lower only in late stage (IV) patients. Receiver-operating characteristic analysis showed that for diagnosis of GC, IL-6 had high specificity (0.97) and low sensitivity (0.39), IL-10 had moderate specificity (0.82) and low sensitivity (0.48), and IL-1ß and IFN-γ showed low specificity (0.43 and 0.53, respectively) and moderate sensitivity (0.76 and 0.71, respectively). CONCLUSIONS: Increased levels of IL-6, IFN-γ, and IL-10 might be useful as diagnostic biomarkers for GC; however, this needs to be confirmed with larger number of patients and with control groups other than blood donors, properly age paired. IL-1ß, IL-6, MCP-1, and TGF-ß differentiate intestinal from diffuse GC. IFN-γ and IL-10 might be useful for diagnosis of early stage GC, and IL-1ß, IL-8, and MCP-1 for late stages of the disease.


Asunto(s)
Biomarcadores de Tumor/sangre , Interferón gamma/sangre , Interleucina-10/sangre , Interleucina-6/sangre , Neoplasias Gástricas/sangre , Adulto , Quimiocina CCL2/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Infecciones por Helicobacter/sangre , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Helicobacter pylori/patogenicidad , Humanos , Inflamación/sangre , Inflamación/patología , Interleucina-1beta/sangre , Masculino , México , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología , Factor de Necrosis Tumoral alfa/sangre
12.
Gynecol Obstet Invest ; 82(6): 592-600, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28147379

RESUMEN

BACKGROUND: Decidual cells play a role in the modulation of the innate immune response to protect pregnancy against infection. Steroid hormones regulate the innate immune response in different tissues, and they are involved in several biological processes like decidualization. The aim of this study was to assess if steroid hormones modulate the innate immunity in endometrial stromal cells (ESCs) and decidual stromal cells (DSCs) in response to group B streptococcus (GBS) infection in vitro. METHODS: Primary cultures of ESC were differentiated into DSC using 36 nM estradiol + 300 nM progesterone, and both were infected with GBS overnight. Concentrations of pro- and anti-inflammatory mediators (interleukin [IL]-1ß, IL-6, tumor necrosis factor [TNF]-α, IL-10, and TGF-ß), chemokines (IL-8 and GCP-2), and human ß-defensins (HBD-1, HBD-2, and HBD-3) were measured in the culture supernatants. RESULTS: DSCs showed a significant increase in IL-6 (p < 0.05), TNF-α (p < 0.05), IL-10 (p < 0.01), and TGF-ß (p < 0.05) secretion after GBS infection, while these changes were not observed in infected ESCs. IL-8 and GCP-2 increased after GBS infection, regardless of decidualization. ß-Defensins 1-3 decreased (p < 0.05) in ESCs after GBS infection, and hormone decidualization preserved the secretion of these antimicrobial peptides. CONCLUSIONS: Decidualization mediated by steroid hormones balance the pro- and anti-inflammatory response at the maternal-fetal interface under infection conditions.


Asunto(s)
Estradiol/farmacología , Estrógenos/farmacología , Inmunidad Innata/efectos de los fármacos , Infecciones Estreptocócicas/prevención & control , Células del Estroma/efectos de los fármacos , Decidua/efectos de los fármacos , Implantación del Embrión , Células Epiteliales/efectos de los fármacos , Femenino , Humanos , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Embarazo , Infecciones Estreptocócicas/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
13.
Arch Microbiol ; 198(2): 199-204, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26537814

RESUMEN

The MAP-LC3 system regulates the intracellular formation of autophagy-associated vacuoles. These vacuoles contain the LC3 protein; thus it has been utilized as a marker to identify autophagosomes. The aim of our study was to investigate whether Haemophilus influenzae strains and their supernatants could activate autophagy in human larynx carcinoma cell line (HEp-2). We demonstrate that higher expression of the LC3B-II protein was induced, particularly by nontypeable Haemophilus influenzae (NTHi) 49766 and by supernatants, containing <50 kDa proteins, of both strains. Ultrastructural studies demonstrate vacuoles with a double membrane and/or membrane material inside, showing similar features to those of autophagic vacuoles. Together, our findings demonstrate that H. influenzae strains and their supernatants trigger an autophagic process.


Asunto(s)
Autofagia/fisiología , Infecciones por Haemophilus/fisiopatología , Haemophilus influenzae/fisiología , Línea Celular Tumoral , Humanos , Proteínas Asociadas a Microtúbulos/genética , Regulación hacia Arriba , Vacuolas/ultraestructura
14.
Front Microbiol ; 7: 2042, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28066364

RESUMEN

In recent years, an increase of uropathogenic Escherichia coli (UPEC) strains with Multidrug-resistant (MDR) and Extensively Drug-resistant (XDR) profiles that complicate therapy for urinary tract infections (UTIs) has been observed and has directly impacted costs and extended hospital stays. The aim of this study was to determine MDR- and XDR-UPEC clinical strains, their virulence genes, their phylogenetic groups and to ascertain their relationship with integrons and genetic diversity. From a collection of 500 UPEC strains, 103 were selected with MDR and XDR characteristics. MDR-UPEC strains were mainly associated with phylogenetic groups D (54.87%) and B2 (39.02%) with a high percentage (≥70%) of several fimbrial genes (ecpA, fimH, csgA, and papGII), an iron uptake gene (chuA), and a toxin gene (hlyA). In addition, a moderate frequency (40-70%) of other genes (iutD, tosA, and bcsA) was observed. XDR-UPEC strains were predominantly associated with phylogenetic groups B2 (47.61%) and D (42.85%), which grouped with ≥80 virulence genes, including ecpA, fimH, csgA, papGII, iutD, and chuA. A moderate frequency (40-70%) of the tosA and hlyA genes was observed. The class 1 and 2 integrons that were identified in the MDR- and XDR-UPEC strains were associated with phylogenetic groups D, B2, and A, while the XDR-UPEC strains that were associated with phylogenetic groups B2, D, and A showed an extended-spectrum beta-lactamase (ESBL) phenotype. The modifying enzymes (aadA1, aadB, aacC, ant1, dfrA1, dfrA17, and aadA4) that were identified in the variable region of class 1 and 2 integrons from the MDR strains showed resistance to gentamycin (56.25 and 66.66%, respectively) and trimethoprim-sulfamethoxazole (84.61 and 66.66%, respectively). The MDR- and XDR-UPEC strains were distributed into seven clusters and were closely related to phylogenic groups B2 and D. The diversity analysis by PFGE showed 42.68% of clones of MDR-UPEC and no clonal association in the XDR-UPEC strains. In conclusion, phylogenetic groups including virulence genes are widely associated with two integron classes (1 and 2) in MDR- and XDR-UPEC strains.

15.
Curr Microbiol ; 71(4): 501-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26202845

RESUMEN

Since a decade, Escherichia coli has been considered an important nosocomial pathogen due to the high number of isolates multiresistant to antimicrobials reported worldwide. In clinical and environmental strains, transposons, plasmids, and integrons are currently considered the principal genetic elements responsible for the acquisition of antibiotic resistance through horizontal transfer. The objective of this research was to correlate the resistance to antibiotics of E. coli clinical strains with the presence class I integrons. In the present study, one hundred E. coli strains were isolated and tested for susceptibility and resistance to antimicrobials. Class 1 integrons were detected by PCR, and the arrangement of gene cassettes was determined by sequencing. Twenty two strains were found to carry Class 1 integrons. Sequence analysis of the variable regions revealed the presence of several gene cassettes, such as dihydrofolate reductases (dfr2d, dfrA17, and dhfrXVb), adenylyl transferases (aadA2, addA5, and addA22), and chloramphenicol efflux pump (cmlA), and oxacillinase (bla OXA-1 ). The dfrA17-addA5 arrangement prevailed upon other integrons in the study. This is the first report of the presence of the dfr2d and dhfrXVb-aadA2 cassette arrangements in a Class 1 integrons from clinical strains of E. coli. In most of the strains, it was found a direct relationship between genetic arrangements and resistance phenotypes. Four integrons were detected in plasmids that might be involved in the resistance genes transfer to other bacteria of clinical importance. Our results confirm the presence of Class 1 integrons and their essential role in the dissemination of resistance cassettes among E. coli strains.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple , Infecciones por Escherichia coli/microbiología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Variación Genética , Integrones , Antiinfecciosos/farmacología , Ciudades , Análisis por Conglomerados , ADN Bacteriano/genética , Pruebas Antimicrobianas de Difusión por Disco , Escherichia coli/clasificación , Escherichia coli/aislamiento & purificación , Genotipo , Hospitales , Humanos , México , Tipificación Molecular , Fenotipo , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
16.
Arch Med Res ; 45(7): 553-60, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25450581

RESUMEN

BACKGROUND AND AIMS: Acinetobacter baumannii is an emerging pathogen worldwide that is most commonly associated with nosocomial infections and multi-drug resistance. In the present study we determined the mechanisms of carbapenem resistance and clonal diversity of A. baumannii nosocomial isolates in Hospital Civil de Guadalajara, Mexico. METHODS: A total of 303 clinical isolates of A. baumannii identified during a period expanding from 2004-2011 were analyzed for carbapenem resistance using several microbiological and molecular methods. Clonal relatedness of these isolates was determined using pulsed-field gel electrophoresis. RESULTS: Of the 303 isolates, 84% were resistant to meropenem, 71.3% to imipenem and 78.3% the resistant isolates were positive for metallo-ß-lactamases as determined by the phenotypic assay. In addition, 49.6% of carbapenem-intermediate or -resistant isolates carried the blaOXA-72 gene and 1.2% carried the blaVIM-1 gene. Efflux pump phenotype was responsible for reduced susceptibility to meropenem in 14.5% and to imipenem in 31.6% of the resistant isolates, respectively in the presence of the efflux pump inhibitor, carbonyl cyanide 3-chlorophenylhydrazone. Strains representing different carbapenem-resistant patterns exhibited reduced expression of 22, 29, 33, and 43 kDa OMPs. Among the bacterial collection studied, 48 different clones were identified, two of which were predominant and persistently transmitted. CONCLUSIONS: Carbapenemase production in combination with efflux pump expression, reduction in OMPs expression and the cross-transmission of clones appear to be major contributors to the high frequency of carbapenem-resistance observed in A. baumannii. To our knowledge, this is the first study to define the molecular mechanisms associated with carbapenem-resistance in A. baumannii in Mexico.


Asunto(s)
Infecciones por Acinetobacter/tratamiento farmacológico , Acinetobacter baumannii/efectos de los fármacos , Proteínas Bacterianas/metabolismo , Carbapenémicos/farmacología , Infección Hospitalaria/tratamiento farmacológico , Farmacorresistencia Bacteriana Múltiple , beta-Lactamasas/metabolismo , Acinetobacter baumannii/aislamiento & purificación , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Transporte Biológico/efectos de los fármacos , Carbapenémicos/metabolismo , Infección Hospitalaria/microbiología , Electroforesis en Gel de Campo Pulsado , Hospitales , Humanos , Hidrazonas/farmacología , Imipenem/farmacología , Meropenem , México , Pruebas de Sensibilidad Microbiana , Tienamicinas/farmacología , beta-Lactamasas/genética
17.
PLoS One ; 8(6): e64623, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23755130

RESUMEN

Helicobacter pylori contains a pathogenicity island, cagPAI, with genes homologous to components of the type IV secretion system (T4SS) of Agrobacterium tumefaciens. The T4SS components assemble a structure that transfers CagA protein and peptidoglycan into host epithelial cells, causing the increased release of interleukin 8 (IL8) from the cells. The Toll-like receptors on neutrophils recognize H. pylori, initiating signaling pathways that enhance the activation of NF-κB. However, the roles of cagPAI and T4SS in the inflammatory response of neutrophils are unknown. We evaluated the participation of cagPAI and T4SS in the response of human neutrophils to H. pylori infection. Neutrophils were isolated from the blood of healthy donors and infected with H. pylori cagPAI(+), cagPAI(-), and cagPAI mutant strains virB4 (-) and virD4 (-). Whereas cagPAI(+) strain 26695 induced the greatest IL8 production, a proinflammatory response, cagPAI(-) strain 8822 induced the greatest IL10 production, an anti-inflammatory response. In contrast, the virB4 (-) and virD4 (-) mutant strains produced significantly more of the two proinflammatory cytokines IL1ß and tumor necrosis factor αthan the cagPAI(+) strain 26695. We observed that H. pylori downregulated the expression of TLRs 2 and 5 but upregulated TLR9 expression in a cagPAI and T4SS-independent manner. These results show for the first time that the response of human neutrophils to H. pylori may vary from a pro-inflammatory to an anti-inflammatory response, depending on cagPAI and the integrity of T4SS.


Asunto(s)
Sistemas de Secreción Bacterianos/genética , Islas Genómicas/genética , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Inflamación/inmunología , Inflamación/microbiología , Neutrófilos/inmunología , Citocinas/metabolismo , Regulación hacia Abajo , Genotipo , Humanos , Mutación/genética , Receptores Toll-Like/metabolismo
18.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 31(3): 130-135, mar. 2013. ilus, tab
Artículo en Inglés | IBECS | ID: ibc-110859

RESUMEN

Introduction Helicobacter pylori adheres to various components of the human saliva. Therefore, the objective of this research was to simultaneously detect H. pylori in saliva and in gastric biopsy, and to determine the agreement between the vacA genotypes in both saliva and gastric biopsy. Materials and methods A total of 162 patients with chronic gastritis and 34 with gastric ulcer were studied, and saliva and biopsy samples were collected from each patient. H. pylori DNA was detected by conventional PCR and nested PCR was used for vacA genotyping. Result sIn 24% of the patients (47/196) H. pylori DNA was found in saliva and in biopsy; 52.5% (103/196) were salivanegative/biopsypositive and 6.6% (13/196) were salivapositive/biopsynegative. In either or both H. pylori vacAs1m1 or s1m2 genotypes were detected in saliva in 41.5% of the patients with chronic gastritis. Forty-seven percent had >1 genotype, and the s1m1/s1m2 combination was found in 36% of them. H. pylori vacAs1m1 and s1m2 were also found in the saliva and biopsy of patients with gastric ulcer. The genotypes found in saliva and biopsy of the same patient had 51.1% agreement. In 27.6% of the 47 patients salivapositive/biopsypositive two genotypes were found in saliva, and one or both in the stomach. Conclusions The s1m1/s1m2 genotypes, alone or together, are found simultaneously in saliva and gastric biopsy of the same patient. These results suggest that H. pylori reaches the oral cavity by various ways, and that saliva can be the transmitting and re-infecting vector (AU)


Introduccion Helicobacter pylori (H. pylori) se adhiere a diversos componentes de la saliva humana, por ello, el objetivo de esta investigación fue detectar H. pylori en saliva y biopsia gástrica y determinar la concordancia entre los genotipos vacA encontrados en saliva y estómago del mismo paciente. Material y métodos Se estudiaron 162 pacientes con gastritis crónica y 34 con úlcera gástrica. De cada paciente se obtuvo una muestra de saliva y biopsia gástrica. El ADN de H. pylori se detectó por PCR convencional y la genotipificación de vacA se hizo por PCR anidada. Resultados En el 24% (47/196) de los pacientes se encontró ADN de H. pylori en saliva y biopsia; el 52,5% (103/196) fueron salivanegativos/biopsiapositivos y el 6,6% (13/196) resultaron salivapositivos/biopsianegativos. En 41,5% de los pacientes con gastritis crónica, se encontró H. pylori vacA s1m1, s1m2 o ambos en saliva. El 47,2% tenían>1 genotipo y en 36% de esos se encontró la combinación s1m1/s1m2. H. pylori vacA s1m1 y s1m2 también se encontró en saliva y biopsia de pacientes con úlcera. El acuerdo entre los genotipos encontrados en saliva y biopsia de los mismos pacientes fue del 51,1%. En el 27,6% de los 47 pacientes salivapositivos/biopsiapositivos se encontraron 2 genotipos en saliva, y uno o los 2 también se encontraron en estómago. Conclusiones Los genotipos s1m1/s1m2 solos o coexistiendo se encuentran simultáneamente en saliva y biopsia de los mismos pacientes. Los resultados sugieren que H. pylori alcanza la cavidad oral por diversas vías y la saliva puede servir de vehículo para la transmisión y reinfección (AU)


Asunto(s)
Humanos , Helicobacter pylori/aislamiento & purificación , Infecciones por Helicobacter/microbiología , Boca/microbiología , Gastritis/microbiología , Úlcera Gástrica/microbiología , Estómago/microbiología , Saliva/microbiología , Genotipo
19.
Enferm Infecc Microbiol Clin ; 31(3): 130-5, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23084752

RESUMEN

INTRODUCTION: Helicobacter pylori adheres to various components of the human saliva. Therefore, the objective of this research was to simultaneously detect H. pylori in saliva and in gastric biopsy, and to determine the agreement between the vacA genotypes in both saliva and gastric biopsy. MATERIALS AND METHODS: A total of 162 patients with chronic gastritis and 34 with gastric ulcer were studied, and saliva and biopsy samples were collected from each patient. H. pylori DNA was detected by conventional PCR and nested PCR was used for vacA genotyping. RESULTS: In 24% of the patients (47/196) H. pylori DNA was found in saliva and in biopsy; 52.5% (103/196) were saliva(negative)/biopsy(positive) and 6.6% (13/196) were saliva(positive)/biopsy(negative). In either or both H. pylori vacAs1m1 or s1m2 genotypes were detected in saliva in 41.5% of the patients with chronic gastritis. Forty-seven percent had >1 genotype, and the s1m1/s1m2 combination was found in 36% of them. H. pylori vacAs1m1 and s1m2 were also found in the saliva and biopsy of patients with gastric ulcer. The genotypes found in saliva and biopsy of the same patient had 51.1% agreement. In 27.6% of the 47 patients saliva(positive)/biopsy(positive) two genotypes were found in saliva, and one or both in the stomach. CONCLUSIONS: The s1m1/s1m2 genotypes, alone or together, are found simultaneously in saliva and gastric biopsy of the same patient. These results suggest that H. pylori reaches the oral cavity by various ways, and that saliva can be the transmitting and re-infecting vector.


Asunto(s)
Proteínas Bacterianas/genética , Gastritis/microbiología , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Boca/microbiología , Úlcera Gástrica/microbiología , Estómago/microbiología , Enfermedad Crónica , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad
20.
Mem Inst Oswaldo Cruz ; 108(8): 1074-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24402145

RESUMEN

Haemophilus influenzae belongs to respiratory tract microbiota. We observed vacuoles formation in previous studies with H. influenzae culture supernatants, so in this work we characterised that cytotoxic effect. We observed an abundant production of acidic cytoplasmic vacuoles due to the presence of a "vacuolating factor" in H. influenzae supernatants which was characterised as thermolabile. Greatest vacuolating activity was observed when utilizing the fraction > 50 kDa. The presence of a large number of vacuoles in HEp-2 cells was verified by transmission electron microscopy and some vacuoles were identified with a double membrane and/or being surrounded by ribosomes. These results suggest similar behaviour to that of vacuolating effects described by autotransporter proteins an undescribed cytotoxic effect induced by H. influenzae.


Asunto(s)
Citotoxinas/toxicidad , Haemophilus influenzae/metabolismo , Vacuolas/microbiología , Células Cultivadas , Citotoxinas/biosíntesis , Haemophilus influenzae/ultraestructura , Microscopía Electrónica de Transmisión , Vacuolas/ultraestructura
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