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De la Rosa-Ramos M.A.,Laboratorio Of Microbiologia Veterinaria | De la Rosa-Ramos M.A.,Laboratorio Of Bacteriologia Medica | Rodriguez-Cruz M.,Laboratorio Of Microbiologia Veterinaria | Lopez-Villegas E.O.,National Polytechnic Institute of Mexico | And 3 more authors.
Avian Pathology | Year: 2015

Ornithobacterium rhinotracheale (ORT) is a Gram-negative bacillus that causes respiratory disease in birds, and directly affects the poultry industry. The mechanisms behind these infections are not completely known. Currently, its capacity to form biofilms on inert surfaces has been reported; however, the conditions for biofilm development have not been described yet. The present work was aimed at identifying the conditions that enhance in vitro biofilm formation and development by ORT. For this, serovars A-E were analysed to assess their ability to induce biofilm development on 96-well flat-bottom polystyrene microtitre plates under diverse conditions: temperature, incubation time, and CO2 concentration. The results obtained showed not only that all serovars have the ability to produce in vitro biofilms, but also that the optimal conditions for biofilm density were 40°C after 72 h at an elevated CO2 concentration. In conclusion, ORT biofilm formation depends on the environmental conditions and may contribute to the persistence of this microorganism. © 2015 Houghton Trust Ltd.


Martinez-Pena M.D.,Laboratorio Of Bacteriologia Medica | Castro-Escarpulli G.,Laboratorio Of Bacteriologia Medica | Aguilera-Arreola M.G.,Laboratorio Of Bacteriologia Medica
BMC Infectious Diseases | Year: 2013

Background: Lactobacillus jensenii, L. iners, L. crispatus and L. gasseri are the most frequently occurring lactobacilli in the vagina. However, the native species vary widely according to the studied population. The present study was performed to genetically determine the identity of Lactobacillus strains present in the vaginal discharge of healthy and bacterial vaginosis (BV) intermediate Mexican women.Methods: In a prospective study, 31 strains preliminarily identified as Lactobacillus species were isolated from 21 samples collected from 105 non-pregnant Mexican women. The samples were classified into groups according to the Nugent score criteria proposed for detection of BV: normal (N), intermediate (I) and bacterial vaginosis (BV). We examined the isolates using culture-based methods as well as molecular analysis of the V1-V3 regions of the 16S rRNA gene. Enterobacterial repetitive intergenic consensus (ERIC) sequence analysis was performed to reject clones.Results: Clinical isolates (25/31) were classified into four groups based on sequencing and analysis of the 16S rRNA gene: L. acidophilus (14/25), L. reuteri (6/25), L. casei (4/25) and L. buchneri (1/25). The remaining six isolates were presumptively identified as Enterococcus species. Within the L. acidophilus group, L. gasseri was the most frequently isolated species, followed by L. jensenii and L. crispatus. L. fermentum, L. rhamnosus and L. brevis were also isolated, and were placed in the L. reuteri, L. casei and L. buchneri groups, respectively. ERIC profile analysis showed intraspecific variability amongst the L. gasseri and L. fermentum species.Conclusions: These findings agree with previous studies showing that L. crispatus, L. gasseri and L. jensenii are consistently present in the healthy vaginal ecosystem. Additional species or phylotypes were detected in the vaginal microbiota of the non-pregnant Mexican (Hispanic-mestizo) population, and thus, these results further our understanding of vaginal lactobacilli colonisation and richness in this particular population. © 2013 Martínez-Peña et al.; licensee BioMed Central Ltd.


Trejo-De La O A.,La Salle University at Cuauhtémoc | Torres J.,Hospital Of Pediatria | Sanchez-Zauco N.,Hospital Of Pediatria | Sanchez-Zauco N.,Hospital Infantil Of Mexico Federico Gomez | And 5 more authors.
Innate Immunity | Year: 2015

Colonization of the gastric mucosa by Helicobacter pylori can lead to peptic ulcer and gastric adenocarcinoma. TLRs are signaling receptors involved in the recognition of microorganisms, and polymorphisms in their genes may influence the innate and adaptive immune response to H. pylori, affecting the clinical outcomes of the infection. We assessed the association between single nucleotide polymorphisms in TLR9 and TLR5 and gastroduodenal diseases. All patients were genotyped by allelic discrimination in regions 1174C->-T and 1775A->-G of TLR5 and -1237T->-C and 2848G->-A of TLR9. The 2848A allele of TLR9 was more frequent in duodenal ulcer and showed an association of risk with this pathology. Polymorphisms in TLR5 were not found to be associated with disease. Patients with polymorphisms in TLR9 and TLR5 expressed significantly lower levels of IL-1β and TNF-α, whereas polymorphisms in TLR5 also decreased the expression of IL-6 and IL-10. Our findings suggest that 2848G->-A polymorphism in TLR9 increases the risk for the development of duodenal ulcer probably by modifying the inflammatory response to H. pylori infection. This is the first study to show an association of 2848A allele of TLR9 with duodenal ulcer and with altered expression of inflammatory cytokines in the gastric mucosa. © SAGE Publications.


Dornelas-Ribeiro M.,Institute Biologia do Exercito | Dornelas-Ribeiro M.,Instituto Estadual Of Hematologia | Dornelas-Ribeiro M.,Hospital Adventista Silvestre | Dornelas-Ribeiro M.,Laboratorio Of Bacteriologia Medica | And 9 more authors.
Memorias do Instituto Oswaldo Cruz | Year: 2012

We assessed fluconazole susceptibility in 52 Candida tropicalis clinical strains using seven antifungal susceptibility methods, including broth microdilution (BMD) [standard M27 A3 (with neutral and acid pH), ATB Fungus 3, Vitek 2 system and flow cytometric analysis] and agar-based methods (disk diffusion and E-test). Trailing growth, detection of cell-associated secreted aspartic proteases (Saps) and morphological and ultrastructural traits of these clinical strains were also examined. The ranges of fluconazole 24 h-minimum inhibitory concentration (MIC) values were similar among all methods. The essential agreement among the methods used for MIC determinations was excellent and all methods categorised all strains as susceptible, except for one strain that showed a minor error. The presence of the trailing effect was assessed by six methods. Trailing positivity was observed for 86.5-100% of the strains. The exception was the BMD-Ac method where trailing growth was not observed. Morphological and ultrastructural alterations were detected in C. tropicalis trailing cells, including mitochondrial swelling and cell walls with irregular shapes. We tested the production of Saps in 13 C. tropicalis strains expressing trailing growth through flow cytometry. Our results showed that all of the C. tropicalis strains up-regulated surface Sap expression after 24 h or 48 h of exposure to fluconazole, which was not observed in untreated yeast strains. We concluded that C. tropicalis strains expressing trailing growth presented some particular features on both biological and ultrastructural levels.


Espinoza M.G.C.,Laboratorio Of Bacteriologia Medica | Vazquez R.G.,Laboratorio Of Bacteriologia Medica | Vazquez R.G.,Centro Medico Nacional La Raza IMSS | Mendez I.M.,Instituto Nacional Of Perinatologia Inper | And 2 more authors.
Journal of Clinical Microbiology | Year: 2011

A novel reverse primer (GLM MR1) was designed for detection of the glmM gene in Helicobacter pylori by PCR. The percentage of amplification in clinical isolates using GLM MR1 was 100% for detection of the glmM gene and 86.36% for the ureA gene. The primer designed is useful for the identification of H. pylori. Copyright © 2011, American Society for Microbiology.


Sanchez-Zauco N.A.,Hospital Infantil Of Mexico Federico Gomez | Sanchez-Zauco N.A.,Centro Medico Nacional Siglo XXI | Sanchez-Zauco N.A.,Laboratorio Of Bacteriologia Medica | Torres J.,Centro Medico Nacional Siglo XXI | And 7 more authors.
PLoS ONE | Year: 2013

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 IL1β 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. © 2013 Sánchez-Zauco et al.


Hernandez Cortez C.,Laboratorio Of Bacteriologia Medica | Aguilera Arreola Ma.G.,Laboratorio Of Bacteriologia Medica | Castro Escarpulli G.,Laboratorio Of Bacteriologia Medica
Enfermedades Infecciosas y Microbiologia | Year: 2011

Gastrointestinal diseases are one of the main public health problems in Mexico. They are transmitted through water and contaminated food as well as through the faecal-oral route. These diseases affect mainly the pediatric population, and their incidence and prevalence depend on the socioeconomic level of the patients. Viruses, parasites, and bacteria are the involved pathogenic agents. In clinical laboratories, search and identification focus mainly on classic pathogens, such as Salmonella, Shigella, Escherichia, Vibrio, Campylobacter, and Yersinia. It is important to consider other pathogens, like Aeromonas, which have been documented in other countries as pathogenic agent of gastrointestinal diseases and markers of fecal contamination in the water. The present text begins with some general aspects on the situation of gastrointestinal diseases, including diarrhea, which is one of the main syndromes affecting children under the age of 5, and its classification, and ends with the description of the main digestive tract diseases. It is important to know the situation of gastrointestinal diseases in our country; therefore, this review focuses, on one side, on some data related to the number of reported cases in the epidemiology bulletin of the Mexican Republic, covering mainly data from 2000 to 2008; as well as on data gathered from other studies performed in our country and other countries, to obtain a clear picture of the situation of these diseases, mainly those of infectious origin.


PubMed | Laboratorio Of Bacteriologia Medica
Type: | Journal: BMC infectious diseases | Year: 2013

Lactobacillus jensenii, L. iners, L. crispatus and L. gasseri are the most frequently occurring lactobacilli in the vagina. However, the native species vary widely according to the studied population. The present study was performed to genetically determine the identity of Lactobacillus strains present in the vaginal discharge of healthy and bacterial vaginosis (BV) intermediate Mexican women.In a prospective study, 31 strains preliminarily identified as Lactobacillus species were isolated from 21 samples collected from 105 non-pregnant Mexican women. The samples were classified into groups according to the Nugent score criteria proposed for detection of BV: normal (N), intermediate (I) and bacterial vaginosis (BV). We examined the isolates using culture-based methods as well as molecular analysis of the V1-V3 regions of the 16S rRNA gene. Enterobacterial repetitive intergenic consensus (ERIC) sequence analysis was performed to reject clones.Clinical isolates (25/31) were classified into four groups based on sequencing and analysis of the 16S rRNA gene: L. acidophilus (14/25), L. reuteri (6/25), L. casei (4/25) and L. buchneri (1/25). The remaining six isolates were presumptively identified as Enterococcus species. Within the L. acidophilus group, L. gasseri was the most frequently isolated species, followed by L. jensenii and L. crispatus. L. fermentum, L. rhamnosus and L. brevis were also isolated, and were placed in the L. reuteri, L. casei and L. buchneri groups, respectively. ERIC profile analysis showed intraspecific variability amongst the L. gasseri and L. fermentum species.These findings agree with previous studies showing that L. crispatus, L. gasseri and L. jensenii are consistently present in the healthy vaginal ecosystem. Additional species or phylotypes were detected in the vaginal microbiota of the non-pregnant Mexican (Hispanic-mestizo) population, and thus, these results further our understanding of vaginal lactobacilli colonisation and richness in this particular population.

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