Multiple surface interaction mechanisms direct the anchoring, co-aggregation and formation of dual-species biofilm between Candida albicans and Helicobacter pylori.

Introduction: Polymicrobial biofilms have a significant impact on pathogenesis of infectious microorganisms. Many human diseases are affected by colonization of multi-species communities affecting negatively the treatments and increase the risks for the health. In particular, in the epithelium of the stomach co-existence between C. albicans and H. pylori has been described, which has been associated to a synergistic effect on ulcer pathogenesis. Objective: The objective of this work was to advance in the understanding of surface interaction between H. pylori and C. albicans for the formation of polymicrobial biofilms. Methods: Studies of microbial surfaces both bacterium, yeast and co-cultures of them were carried out by infrared spectroscopy, deconvolution analysis, transmission and scanning electron microscopies, and optic microscopy. Additional methods were used to contrast the results as dynamic light scattering, contact angle, agarose gel electrophoresis and gene amplification. Results: Several surface interaction mechanisms promote the anchoring of H. pylori on C. albicans, cell co-aggregation, and polymicrobial biofilm formation, main identified interactions were: (i) hydrophobic interactions between non-polar peptide chains and lipid structures, characterized by θw among 84.9 ± 1.6 (γ = 22.78 mJ/m2 with 95.3 of dispersive contribution) and 76.6 ± 3.8 (γ = 17.34 mJ/m2, 40.2 of dispersive contribution) for C. albicans and H. pylori, respectively, (ii) hydrogen bonds between surface components of yeast and bacterium (e.g., -S-H⋅⋅⋅NH2- or -S-H⋅⋅⋅O[bond, double bond]CO-) and (iii) thiol-mediated surface interactions identified by displacements to lower wavenumbers (Δv = 5 cm-1). Evidence of internalization and electrostatic interactions were not evidenced. All observations were congruent with the biofilm formation, including the identification of small-size biostructures (i.e., 122-459 nm) associated with extracellular proteins, extracellular DNA, or outer membrane vesicles were observed characteristic of biofilm formation. Conclusion: It is concluded that biofilm is formed by co-aggregation after anchoring of H. pylori on C. albicans. Several surface interactions were associated with the prevalence of H. pylori, the possibility to find C. albicans in the stomach epithelium infected by H. pylori, but also, strength interactions could be interfering in experimental observations associated with bacterial-DNA detection in culture mixtures.

Characterization of the Bacterial Biofilm Communities Present in Reverse-Osmosis Water Systems for Haemodialysis.

Biofilm in reverse osmosis (RO) membranes is a common problem in water treatment at haemodialysis facilities. Bacteria adhere and proliferate on RO membranes, forming biofilms, obstructing and damaging the membranes and allowing the transfer of bacteria and/or cellular components potentially harmful to the health of haemodialysis patients. Our aim was to characterize the bacterial community associated to biofilm of RO membranes and to identify potentially pathogenic bacteria present in the haemodialysis systems of two dialysis centres in Chile. The diversity of the bacterial communities present on RO membranes and potable and osmosed water samples was evaluated using Illumina sequencing. Additionally, bacteria from potable water, osmosed water and RO membrane samples were isolated, characterized and identified by Sanger's sequencing. The molecular analyses of metagenomics showed that the phyla having a greater relative abundance in both dialysis centres were Proteobacteria and Planctomycetes. Pseudomonas, Stenotrophomonas, Agrobacterium, Pigmentiphaga, Ralstonia, Arthrobacter, Bacteroides and Staphylococcus were bacterial genera isolated from the different samples obtained at both haemodialysis centres. Pseudomonas spp. was a bacterial genus with greater frequency in all samples. Pseudomonas and Staphylococcus showed higher levels of resistance to the antibiotics tested. Results demonstrated the presence of potentially pathogenic bacteria, showing resistance to antimicrobials on RO membranes and in osmosed water in both dialysis centres studied.

Propolis polyphenolic compounds affect the viability and structure of Helicobacter pylori in vitro

ABSTRACT To evaluate the anti-Helicobacter pylori activity of the major polyphenol compounds of propolis and their cellular damage, both as single molecule or in combination. Honey bees propolis were fractionated by using CPC and preparative HPLC. Four major polyphenols (chrysin, pinocembrin, galangin and caffeic acid phenethyl ester) were identified by thin layer chromatography-mass spectroscopy and liquid chromatography-mass spectroscopy. These compounds inhibited both ATCC and clinical H. pylori strains, with caffeic acid phenethyl ester being the most active. The four compounds presented minimum inhibitory concentration in the range 256-1024 µg ml−1 and a fractional inhibitory concentration of 64-512 µg ml−1. In mixtures all compounds showed an indifference effect (FIC < 0.15) but chrysin + galangin which was synergistic (FIC = 2.0). Killing curves show a similar behavior as the antibiotic amoxycillin. On the other hand, analyses by transmission electron microscopy at sub inhibitory concentration show vesicle formation and cell lysis after exposition to both individual polyphenol compounds and in mixture. The major compounds of propolis show anti-H. pylori activity both as individual compounds and in mixture. When combined they present mainly indifference but exert a lytic activity upon H. pylori, suggesting a potential bactericidal activity of propolis.

Dinámica de la infección por Helicobacter pylori en lactantes durante los primeros 6 meses de vida / Dynamics of Helicobacter pylori infection in infants during the first six months of life

Introducción: Helicobacter pylori constituye un problema de salud mundial principalmente por el elevado porcentaje de infección y la ineficacia en los tratamientos. Para prevenir la infección resulta clave conocer la edad de adquisición. Pacientes: Participaron 67 madres y sus respectivos hijos. Para evaluar la presencia de H. pylori, las deposiciones de la madre y de su hijo fueron analizadas mediante el test HpSA. Resultados: El 71,6% (48/67) de las embarazadas a término fueron H. pylori positivas. En los recién nacidos, el 8,96% (6/67) de ellos presentaron colonización/infección persistente para H. pylori. Durante el primer mes de vida se observó una prevalencia e incidencia de infección del 23,9 y 13%, respectivamente. Conclusión: Los resultados, en conjunto, sugieren que durante el primer mes de vida existe un alto riesgo de infección por H. pylori, pudiendo ser esta incluso de tipo persistente

Introduction: Mainly due to the high percentage of infection and the ineffectiveness of treatments, Helicobacter pylori is a global health problem. Knowing the age at acquisition is key to preventing the infection. Patients: Sixty-seven mothers and their respective children participated. To evaluate the presence of H. pylori, the faeces of the mother and her child were analysed using the HpSA antigen test. Results: 71.6% (48/67) of pregnant mothers were positive for H. pylori at the term of their pregnancy. In newborns, 8.96% (6/67) of them showed H. pylori colonisation/persistent infection. During the first month of life, a prevalence and incidence of infection of 23.9% and 13%, respectively, was observed. Conclusion: Overall, the results suggest that there is a high risk of H. pylori infection during the first month of life, even of the persistent type

Dynamics of Helicobacter pylori infection in infants during the first six months of life. / Dinámica de la infección por Helicobacter pylori en lactantes durante los primeros 6 meses de vida.

INTRODUCTION: Mainly due to the high percentage of infection and the ineffectiveness of treatments, Helicobacter pylori is a global health problem. Knowing the age at acquisition is key to preventing the infection. PATIENTS: Sixty-seven mothers and their respective children participated. To evaluate the presence of H. pylori, the faeces of the mother and her child were analysed using the HpSA antigen test. RESULTS: 71.6% (48/67) of pregnant mothers were positive for H. pylori at the term of their pregnancy. In newborns, 8.96% (6/67) of them showed H. pylori colonisation/persistent infection. During the first month of life, a prevalence and incidence of infection of 23.9% and 13%, respectively, was observed. CONCLUSION: Overall, the results suggest that there is a high risk of H. pylori infection during the first month of life, even of the persistent type.

Detection of intracellular Helicobacter pylori in Candida. SPP from neonate oral swabs.

BACKGROUND: There is evidence of detection of Helicobacter pylori (H. pylori) in the stool of newborns and in the yeast that colonizes the oral cavity of this age group. However, there is a lack of research to confirm it. This study proposes to determine the existence of the bacteria at an early age, specifically in newborns. OBJECTIVE: To identify intracellular H. pylori in oral yeasts and to detect antigens of the bacteria in newborn stools. METHODOLOGY: Cross-sectional and descriptive study. Samples were obtained from infants (oral swab and meconium). Identification of yeast species was performed using the following techniques: CHROMagar Candida, Germinal Tube Test and API Candida Identification System, then the yeasts were observed by light microscopy and fluorescence. Detection of H. pylori antigen in meconium and PCR were performed to amplify specific genes of the bacterium (rRNA16S, cagA, vacA s1a, vacA s1b, vacA s2, vacA m1, vacA m2 and dupA). RESULTS: Intracellular H. pylori was detected in yeast of the species Candida glabrata (C. glabrata) isolated from an oral swab of a newborn. CONCLUSION: The results of this study evidenced the existence of intracellular H. pylori in newborns.

Detection of intracellular Helicobacter pylori in Candida. SPP from neonate oral swabs

SUMMARY BACKGROUND: There is evidence of detection of Helicobacter pylori (H. pylori) in the stool of newborns and in the yeast that colonizes the oral cavity of this age group. However, there is a lack of research to confirm it. This study proposes to determine the existence of the bacteria at an early age, specifically in newborns. OBJECTIVE: To identify intracellular H. pylori in oral yeasts and to detect antigens of the bacteria in newborn stools. METHODOLOGY: Cross-sectional and descriptive study. Samples were obtained from infants (oral swab and meconium). Identification of yeast species was performed using the following techniques: CHROMagar Candida, Germinal Tube Test and API Candida Identification System, then the yeasts were observed by light microscopy and fluorescence. Detection of H. pylori antigen in meconium and PCR were performed to amplify specific genes of the bacterium (rRNA16S, cagA, vacA s1a, vacA s1b, vacA s2, vacA m1, vacA m2 and dupA). RESULTS: Intracellular H. pylori was detected in yeast of the species Candida glabrata (C. glabrata) isolated from an oral swab of a newborn. CONCLUSION: The results of this study evidenced the existence of intracellular H. pylori in newborns.

RESUMO ANTECEDENTES: Há evidências de detecçâo de Helicobacter pylori (H. pylori) em fezes de recém-nascidos, como também dentro de leveduras que colonizam a cavidade oral dessa faixa etária. No entanto, faltam investigações que confirmem esses achados. OBJETIVO: Identificar H. pylori intracelular em leveduras de origem oral e detectar antígenos dessa bactéria em fezes neonatais. METODOLOGIA: Estudo transversal e descritivo. As amostras foram obtidas de bebês (zaragatoa oral e mecônio). As identificações das espécies de leveduras foram realizadas utilizando as seguintes técnicas: CHROMagar Candida, teste de tubo germinativo e sistema de identificação API Cândida. As leveduras foram observadas por microscopía óptica e fluorescência. Realizou-se a detecçâo de antígeno de H. pylori em mecônio e PCR para a amplificação de genes específicos desta bactéria (rRNA16S, cagA, vacA s1a, vacA s1b, vacA s2, vacA m1, vacA m2 e dupA). RESULTADOS: Foi detectado H. pylori intracelular em leveduras da espécie Candida glabrata (C. glabrata) isoladas a partir de zaragatoas oral de um recém-nascido. CONCLUSÃO: Os resultados deste estudo evidenciaram a existência interna de levedura de H. pylori em recém-nascidos.

Characterization of Lactobacillus fermentum UCO-979C, a probiotic strain with a potent anti-Helicobacter pylori activity

Background: Helicobacter pylori is considered as the main risk factor in the development of gastric cancer. In the present study, we performed a detailed characterization of the probiotic properties and the anti-H. pylori activity of a previously isolated lactobacillus strain ­ Lactobacillus fermentum UCO-979C ­ obtained from human gut. Results: The strain tolerated pH 3.0; grew in the presence of 2% bile salts; produced lactic acid and hydrogen peroxide; aggregated in saline solution; showed high hydrophobicity; showed high adherence to glass; Caco-2 and gastric adenocarcinoma human cells (AGS) cells; showed an efficient colonization in Mongolian Gerbils; and potently inhibited the growth and urease activity of H. pylori strains. L. fermentum UCO-979C significantly inhibited H. pylori-induced IL-8 production in AGS cells and reduced the viability of H. pylori. With regard to innocuousness, the strain UCO-979C was susceptible to several antibiotics and did not produce histamine or beta-haemolysis in blood agar containing red blood cells from various origins. Conclusion: The results demonstrated that L. fermentum UCO-979C is a very good candidate as a probiotic for the protection of humans against H. pylori infections.

Microbiota dysbiosis: a new piece in the understanding of the carcinogenesis puzzle.

Cancer is defined as an uncontrolled proliferation of malignant cells in a host and it is one of the main causes of death worldwide. Genetic and environmental factors play an important role in its development, and the involvement of microbial communities has also recently been recognized. The close relationship that characterizes the colonization by human commensal communities involves health risks, particularly when the homeostasis is disturbed. It has been hypothesized that this process may lead to cancer by modulating the inflammatory response of the host, by the production of carcinogenic metabolic products or by the production of toxins, which disrupt the cell cycle. The metabolic effects of the intestinal microbiota have been studied in greater detail in the gastrointestinal tract, and it has been recognized that microbial communities of other body surfaces can cause effects either locally or at a distance. In vitro and in vivo studies have allowed the characterization of the microbiota and the establishment of a cause and effect relationship with some types of cancer. Nevertheless, despite the results, representative studies are necessary to validate the findings and definitively establish the role of microbiota in cancer development in order to open the possibility of promising therapeutic and diagnostic applications. Thus, the aims of this review are to briefly examine the available evidence, and to analyse the mechanisms described for pancreatic, lung, colorectal cancer , oral squamous cell carcinoma and hepatocellular carcinoma and the impact of the current knowledge about the effects of the microbiota on carcinogenesis.

Biofilm Forming Lactobacillus: New Challenges for the Development of Probiotics.

Probiotics are live bacteria, generally administered in food, conferring beneficial effects to the host because they help to prevent or treat diseases, the majority of which are gastrointestinal. Numerous investigations have verified the beneficial effect of probiotic strains in biofilm form, including increased resistance to temperature, gastric pH and mechanical forces to that of their planktonic counterparts. In addition, the development of new encapsulation technologies, which have exploited the properties of biofilms in the creation of double coated capsules, has given origin to fourth generation probiotics. Up to now, reviews have focused on the detrimental effects of biofilms associated with pathogenic bacteria. Therefore, this work aims to amalgamate information describing the biofilms of Lactobacillus strains which are used as probiotics, particularly L. rhamnosus, L. plantarum, L. reuteri, and L. fermentum. Additionally, we have reviewed the development of probiotics using technology inspired by biofilms.

Isolation of lactic acid bacteria from swine milk and characterization of potential probiotic strains with antagonistic effects against swine-associated gastrointestinal pathogens.

Probiotics are usually isolated from the gastrointestinal tract of humans and animals. The search of probiotics in human milk is a recent field of research, as the existence of the human milk microbiome was discovered only about a decade ago. To our knowledge, no reports regarding the potential probiotic effect of bacteria from swine milk have been published. In this work, we isolated several lactic acid bacteria from swine milk and evaluated them for them potential as probiotics. Among the isolated strains, Lactobacillus curvatus TUCO-5E showed antagonistic effects against swine-associated gastrointestinal pathogens. TUCO-5E was able to reduce the growth of enterotoxigenic and enterohemorrhagic Escherichia coli strains as well as pathogenic salmonella. In vitro exclusion and displacement assays in intestinal epithelial cells showed a remarkable antagonistic effect for L. curvatus TUCO-5E against Salmonella sp. strain TUCO-I7 and Salmonella enterica ATCC 13096. Moreover, by using a mouse model of Salmonella infection, we were able to demonstrate that preventative administration of L. curvatus TUCO-5E for 5 consecutive days was capable of decreasing the number of Salmonella enterica serovar Typhimurium in the liver and spleen of treated mice, compared with the controls, and prevented dissemination of the pathogen to the blood stream. Therefore, we have demonstrated here that swine milk is an interesting source of beneficial bacteria. In addition, the results of this work suggest that L. curvatus TUCO-5E is a good candidate to study in vivo the protective effect of probiotics against intestinal infection and damage induced by Salmonella infection in the porcine host.

Draft Genome Sequence of a Probiotic Strain, Lactobacillus fermentum UCO-979C.

This report describes a draft genome sequence of Lactobacillus fermentum strain UCO-979C. The reads generated by a Ion Torrent PGM were assembled into contigs, with a total size of 2.01 Mb. The data were annotated using the NCBI GenBank and RAST servers. Specific features of the genome are highlighted.

Effect of pH in the survival of Lactobacillus salivarius strain UCO_979C wild type and the pH acid acclimated variant

Background Bacterial acclimation involves cellular changes permitting the survival of a microorganism to prolonged acid pH exposure. The general aim of this work is to support this idea by determining the effect of pH in the survival of the human gastric derived probiotic strain Lactobacillus salivarius UCO_979C-1 (wild type) and L. salivarius UCO_979C-2 (acclimation to pH 2.6), which possesses anti-Helicobacter pylori properties. Results To assess this aim, the exopolysaccharide production through the phenol-sulfuric acid method was evaluated. Moreover, morphological and structural changes by transmission and scanning electron microscopy were observed. The bacterial survival was measured by viable count. The results showed that the acclimated variant strain synthesized higher levels of exopolysaccharide (690 ± 0.03 mg/L) more than the wild type (450 ± 0.12 mg/L). In addition, the acclimated variant preserved the viable count at pH 2.6 for 48 h, whereas the wild type strain decreases after 6 h and was non-viable at 24 h. Conclusion The results suggest that the acid stress acclimation of the strain L. salivarius UCO_979C-1 modified some cellular properties making this strain potentially useful as a gastric probiotic.

Variations in periplasmic loop interactions determine the pH-dependent activity of the hexameric urea transporter UreI from Helicobacter pylori: a molecular dynamics study.

BACKGROUND: Helicobacter pylori is an important factor in the development of diseases such as ulcer and gastric cancer. This bacterium uses a periplasmic transporter, UreI, to deliver urea to the intracelullar space, where later it is transformed into ammonia by the cytoplasmic enzyme urease to survive the acidic condition of the human stomach. The UreI transporter presents a pH-dependent activity, where this pH-dependence remains unknown at a structural level. Althought the existance of several protonable residues in the periplasmic loops are related to the pH-dependent activity, we find interesting to have a clear view of the conformational changes involved in this phenomena through a molecular dynamic study. RESULTS: Molecular dynamic simulations of the UreI transporter at three different pH conditions were performed, revealing two main pH-dependent conformations, which we present as the open and close states. We find that salt bridges between the periplasmic loops are crucial interactions that stabilize these conformations. Besides, a cooperative behaviour exists between the six subunits of the system that is necessary to fulfill the activity of this transporter. CONCLUSIONS: We found different pH-dependent conformations of the urea transporter UreI from Helicobacter pylori, which are related to salt-bridge interactions in the periplasmic regions. The behaviour of every channel in the system is not independent, given the existance of a cooperative behaviour through the formation of salt-bridges between the subunits of the hexameric system. We believe that our results will be related to the generation of new eradication therapies using this transporter as an attractive target, denoting that the knowledge of the possible pH-dependent conformations adopted for this transporter are important for the development of rational drug design approximations.

Management of Helicobacter pylori infection in Latin America: a Delphi technique-based consensus.

AIM: To optimize diagnosis and treatment guidelines for this geographic region, a panel of gastroenterologists, epidemiologists, and basic scientists carried out a structured evaluation of available literature. METHODS: Relevant questions were distributed among the experts, who generated draft statements for consideration by the entire panel. A modified three-round Delphi technique method was used to reach consensus. Critical input was also obtained from representatives of the concerned medical community. The quality of the evidence and level of recommendation supporting each statement was graded according to United States Preventive Services Task Force criteria. RESULTS: A group of ten experts was established. The survey included 15 open-ended questions that were distributed among the experts, who assessed the articles associated with each question. The levels of agreement achieved by the panel were 50% in the first round, 73.3% in the second round and 100% in the third round. Main consensus recommendations included: (1) when available, urea breath and stool antigen test (HpSA) should be used for non-invasive diagnosis; (2) detect and eradicate Helicobacter pylori (H. pylori) in all gastroscopy patients to decrease risk of peptic ulcer disease, prevent o retard progression in patients with preneoplastic lesions, and to prevent recurrence in patients treated for gastric cancer; (3) further investigate implementation issues and health outcomes of H. pylori eradication for primary prevention of gastric cancer in high-risk populations; (4) prescribe standard 14-d triple therapy or sequential therapy for first-line treatment; (5) routinely assess eradication success post-treatment in clinical settings; and (6) select second- and third-line therapies according to antibiotic susceptibility testing. CONCLUSION: These achievable steps toward better region-specific management can be expected to improve clinical health outcomes.

Biofilm and Helicobacter pylori: from environment to human host.

Helicobacter pylori (H. pylori) is a Gram negative pathogen that selectively colonizes the human gastric epithelium. Over 50% of the world population is infected with H. pylori reaching up to 90% of infected individuals in developing countries. Nonetheless the increased impact upon public health care, its reservoir and the transmission pathway of the species has not been clearly established yet. Molecular studies allowed the detection of H. pylori in various aquatic environments, even forming biofilm in tap water distribution systems in several countries, suggesting a role of water as a possible reservoir of the pathogen. The persistence of human infection with H. pylori and the resistance of clinical isolates to commonly used antibiotics in eradication therapy have been related to the genetic variability of the species and its ability to develop biofilm, demonstrated both in vivo and in vitro experiments. Thus, during the last years, experimental work with this pathogen has been focused in the search for biofilm inhibitors and biofilm destabilizing agents. However, only two anti- H. pylori biofilm disrupting agents have been successfully used: Curcumin - a natural dye - and N-acetyl cysteine - a mucolytic agent used in respiratory diseases. The main goal of this review was to discuss the evidences available in the literature supporting the ability of H. pylori to form biofilm upon various surfaces in aquatic environments, both in vivo and in vitro. The results published and our own observations suggest that the ability of H. pylori to form biofilm may be important for surviving under stress conditions or in the spread of the infection among humans, mainly through natural water sources and water distribution systems.

Catechin-based procyanidins from Peumus boldus Mol. aqueous extract inhibit Helicobacter pylori urease and adherence to adenocarcinoma gastric cells.

In this work, the anti-Helicobacter pylori effect of an aqueous extract from dried leaves of Peumus boldus Mol. (Monimiaceae) was evaluated. This extract displayed high inhibitory activity against H. pylori urease. Therefore, in order to clarify the type of substances responsible for such effect, a bioassay-guided fractionation strategy was carried out. The active compounds in the fractions were characterized through different chromatographic methods (RP-HPLC; HILIC-HPLC). The fraction named F5 (mDP = 7.8) from aqueous extract was the most active against H. pylori urease with an IC50 = 15.9 µg gallic acid equivalents (GAE)/mL. HPLC analysis evidenced that F5 was composed mainly by catechin-derived proanthocyanidins (LC-MS and phloroglucinolysis). The anti-adherent effect of boldo was assessed by co-culture of H. pylori and AGS cells. Both the aqueous extract and F5 showed an anti-adherent effect in a concentration-dependent manner. An 89.3% of inhibition was reached at 2.0 mg GAE/mL of boldo extract. In conjunction, our results suggest that boldo extract has a potent anti-urease activity and anti-adherent effect against H. pylori, properties directly linked with the presence of catechin-derived proanthocyanidins.

The problem of Helicobacter pylori resistance to antibiotics: a systematic review in Latin America.

OBJECTIVES: Latin America has a high prevalence of Helicobacter pylori infection and associated diseases, including gastric cancer. Antibiotic therapy can eradicate the bacterial infection and decrease associated morbidity and mortality. To tailor recommendations for optimal treatments, we summarized published literature and calculated region- and country-specific prevalences of antibiotic resistance. METHODS: Searches of PubMed and regional databases for observational studies evaluating H. pylori antibiotic resistance yielded a total of 59 independent studies (56 in adults, 2 in children, and 1 in both groups) published up to October 2013 regarding H. pylori isolates collected between 1988 and 2011. Study-specific prevalences of primary resistance to commonly prescribed antibiotics were summarized using random-effects models. Between-study heterogeneity was assessed by meta-regression. As a sensitivity analysis, we extended our research to studies of patients with prior H. pylori-eradication therapy. RESULTS: Summary prevalences of antimicrobial primary resistance among adults varied by antibiotic, including 12% for clarithromycin (n=35 studies), 53% for metronidazole (n=34), 4% for amoxicillin (n=28), 6% for tetracycline (n=20), 3% for furazolidone (n=6), 15% for fluoroquinolones (n=5), and 8% for dual clarithromycin and metronidazole (n=10). Resistance prevalence varied significantly by country, but not by year of sample collection. Analyses including studies of patients with prior therapy yielded similar estimates. Pediatric reports were too few to be summarized by meta-analysis. CONCLUSIONS: Resistance to first-line anti-H. pylori antibiotics is high in Latin American populations. In some countries, the empirical use of clarithromycin without susceptibility testing may not be appropriate. These findings stress the need for appropriate surveillance programs, improved antimicrobial regulations, and increased public awareness.

Low co-existence rates of Lactobacillus spp. and Helicobacter pylori detected in gastric biopsies from patients with gastrointestinal symptoms.

BACKGROUND: bacterial diversity of the stomach includes various species. Among them, Helicobacter pylori, a microorganism which has been associated to gastric diseases, is frequently isolated in this habitat. In addition, Lactobacillus spp., a genus including probiotic strains, has also been documented in this habitat. The co-existence of these two species in the stomach of symptomatic patient needs to be elucidated. AIMS: our goal was to establish if Lactobacillus spp. and H. pylori co-exist in the stomach mucosa of symptomatic patients. METHODS: gastric biopsies (antrum and/or the body) from 427 Chilean patients with gastrointestinal discomfort were analyzed. The H. pylori infection and/or Lactobacillus spp. colonization status was determined for each patient by standard culture techniques, and statistical correlations between the presence of those species and the age, gender, or the severity of the gastric disease were also established. RESULTS: only 6.1% of the samples presented co-existence of Lactobacillus spp. and H. pylori. This former species was isolated in 42.6% of the patients as unique species, while Lactobacillus spp. was isolated as single species in 19.4% of the individuals. Chronic non-atrophic gastritis was prevalent in Lactobacillus spp. non colonized individuals, while chronic non-atrophic and chronic atrophic gastritis diagnosis was similar in Lactobacillus spp. harbouring individuals (p < 0.001). The presence of Lactobacillus spp. Significantly increased with age (p = 0.005), independently of gender. CONCLUSION: the negative Pearson correlation between Lactobacillus spp. and H. pylori (r = -0.112, p = 0.020) indicates that the co-existence of both species is low in human gastric mucosa of symptomatic patients.

Evidence for Kelp Gulls (Larus dominicanus) and Franklin's Gulls (Leucophaeus pipixcan) as carriers of Salmonella by real-time polymerase chain reaction.

Polymerase chain reaction confirmed that two gull species in Talcahuano, Chile, shed Salmonella. Fecal samples from resident Larus dominicanus had prevalences of 51.2% for Salmonella spp. and 26.3% for Salmonella Enteritidis. Prevalences in samples from migratory Leucophaeus pipixcan were 75% and 30% respectively. Risks to public health may exist.