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As part of a larger study on Epsilonproteobacteria carried by wild birds in the city of Valdivia (southern Chile), two curved rod-shaped Gram-stain-negative strains (A82T and WB-40) were recovered from faecal samples and subjected to a taxonomic study. Results of a genus-specific PCR showed that these isolates belonged to the genus Helicobacter. Further identification by 16S rRNA and hsp60 (60 kDa heat-shock protein) gene sequence analysis revealed that they formed a separate phylogenetic clade, different from other known Helicobacter species with ‘Helicobacter burdigaliensis’ CNRCH 2005/566HT and Helicobacter valdiviensis WBE14T being the most closely related species. This was confirmed by core-genome phylogeny as well as digital DNA–DNA hybridization and average nucleotide identity analyses between the genomes of strains A82T and WB-40 and all other Helicobacter species. The draft genome sequences of A82T and WB-40, obtained by Illumina NextSeq 2000 sequencing, consisted of 1.6 Mb with a G+C content of 31.9–32.0 mol%. The results obtained from the phylogenetic and genomic characteri-zation, together with their different morphological and biochemical features, revealed that these two strains represent a novel species, for which we propose the name Helicobacter ibis sp. nov. with A82T (=LMG 32718T=CCCT 22.04T) as the type strain.

Background: Despite the fact that Helicobacter spp. has been detected in equine gastric mucosa, no evidence exists about this infection in Colombian horses affected by equine ulcerative gastric syndrome (EGUS), nor in dental tartar. Objective: To detect Helicobacter spp. DNA in equine gastric mucosa and dental tartar and determine the relationship between the presence of Helicobacter spp. and gastric lesions. Methods: Samples of glandular gastric mucosa and dental tartar were collected from 30 equine slaughterhouses. Macroscopic lesions of the stomachs were classified and the total DNA in all samples was extracted using a commercial extraction kit. A final-point PCR was performed using primers for amplification of a segment of 251 bp of the gene encoding the 16s rRNA region; the amplified fragments were subjected to a second PCR to determine the presence of H. pylori, the VacA gene was typified. The resulting amplicons were sequenced. Results: It was possible to amplify 16s rRNA in several samples but there was no amplification of VacA. Fragments of the sequences were compatible with H. heilmannii. The 23.3 and 10% of gastric and tartar samples were positive for 16s rRNA of Helicobacter spp., respectively. Conclusion: Although genetic material of Helicobacter spp. was found in some animals, there was no relationship with gastric lesions. It is possible that helicobacteriosis has no bearing in EGUS etiology., Antecedentes: Apesar do Helicobacter spp. ter sido detectado na mucosa gástrica de equinos, não há evidências dessa infecção em cavalos crioulos colombianos afetados pela síndrome ulcerativa gástrica (SUGE), ou no sarro. Objetivo: Detectar ADN de Helicobacter spp. na mucosa gástrica e do sarro dental de equinos, e determinar a relação entre a presença de Helicobacter spp. e lesões gástricas. Métodos: Amostras de mucosa gástrica glandular e sarro dental foram coletadas de 30 equinos de abatedouro, as lesões macroscópicas dos estômagos foram classificadas. Se realizou extração de ADN total em todas as amostras através de kit comercial. Realizou-se PCR ponto final, amplificando o segmento de 251 pb do gene que codifica para a região 16s ARNr; os fragmentos amplificados foram sometidos novamente a PCR para determinar a presença de H. pylori, ao tipificar o gene VacA, e seguidamente foram sequenciados. Resultados: O houve amplificação do 16s ARNr em várias amostras, mas não amplificação de VacA. Fragmentos das sequencias foram compatíveis com H. heilmannii. O 23,3 e 10% das amostras gástricas e do sarro foram positivas para 16s ARNr de Helicobacter, respectivamente. Conclusão: Embora material genético de Helicobacter spp. encontrou-se em algumos animais não houve relação com lesões gástricas. Possivelmente a helicobacterioses não tem papel relevante na etiologia da SUGE., Antecedentes: A pesar de que se ha detectado Helicobacter spp. en mucosa gástrica equina, no existe evidencia de esta infección en caballos criollos colombianos afectados por síndrome ulcerativo gástrico (SUGE), ni tampoco reportes en sarro dental. Objetivo: Detectar ADN de Helicobacter spp. en sarro dental y mucosa gástrica de equinos, y determinar la relación entre la presencia de la bacteria y lesiones gástricas. Métodos: Las muestras de mucosa glandular gástrica y sarro dental fueron colectadas de 30 equinos que se encontraban en planta de beneficio. Las lesiones macroscópicas fueron clasificadas y el ADN total de las muestras fue extraído utilizando un kit comercial. Se desarrolló PCR convencional usando cebadores específicos para la amplificación de un segmento de 251 pb de un gen que codifica la región 16S del ARNr; los fragmentos amplificados fueron sometidos a una segunda PCR para determinar la presencia de H. pylori mediante la amplificación del gen VacA. Los amplificados resultantes fueron secuenciados. Resultados: Fue posible amplificar 16s ARNr en varias muestras, pero no hubo amplificación de VacA. Los fragmentos de las secuencias fueron compatibles con H. heilmannii. El 23,3 y 10% de las muestras gástricas y sarro fueron positivas para 16s ARNr de Helicobacter spp., respectivamente. Conclusión: Aunque el material genético de Helicobacter spp. se encontró en algunos animales, no hubo relación con las lesiones gástricas. Es posible que la helicobacteriosis no tenga incidencia en la etiología del EGUS.

Helicobacter pylori infection triggers inflammation that may lead to gastritis, stomach ulcers and cancer. Probiotic bacteria, such as Lactobacillus, have been of interest as treatment options, however, little is known about the molecular mechanisms of Lactobacillus-mediated inhibition of H. pylori pathogenesis. In this work, we investigated the effect of Lactobacillus culture supernatants, so-called conditioned medium (CM), from two gastric isolates, L. gasseri and L. oris, on the expression of transcriptional regulators in H. pylori. Among the four known two-component systems (TCSs), i.e., ArsRS, FlgRS, CheAY and CrdRS, the flagellar regulator gene flgR and the acid resistance associated arsS gene were down-regulated by L. gasseri CM, whereas expression of the other TCS-genes remained unaffected. L. gasseri CM also reduced the motility of H. pylori, which is in line with reduced flgR expression. Furthermore, among six transcription factors of H. pylori only the ferric uptake regulator gene fur was regulated by L. gasseri CM. Deletion of fur further led to dramatically increased sensitivity to the antimicrobial peptide LL-37. Taken together, the results highlight that released/secreted factors of some lactobacilli, but not all, downregulate transcriptional regulators involved in motility, acid tolerance and LL-37 sensitivity of H. pylori.

Many bacteria and archaea rely on chemotaxis signal transduction systems for optimal fitness. These complex, multiprotein signaling systems have core components found in all chemotactic microbes, as well as variable proteins found in only some species. We do not yet understand why these variations exist or whether there are specific niches that favor particular chemotaxis signaling organization. One variation is in the presence/absence of the chemotaxis methylation adaptation enzymes CheB and CheR. Genes for CheB and CheR are missing in the gastric pathogen Helicobacter pylori but present in related Helicobacter that colonize the liver or intestine. In this work, we asked whether there was a general pattern of CheB/CheR across multiple Helicobacter species. Helicobacter spp. all possess chemotactic behavior, based on the presence of genes for core signaling proteins CheA, CheW, and chemoreceptors. Genes for the CheB and CheR proteins, in contrast, were variably present. Niche mapping supported the idea that these genes were present in enterohepatic Helicobacter species and absent in gastric ones. We then analyzed whether there were differences between gastric and enterohepatic species in the CheB/CheR chemoreceptor target methylation sites. Indeed, these sites were less conserved in gastric species that lack CheB/CheR. Lastly, we determined that cheB and cheR could serve as markers to indicate whether an unknown Helicobacter species was of enterohepatic or gastric origin. Overall, these findings suggest the interesting idea that methylation-based adaptation is not required in specific environments, particularly the stomach. IMPORTANCE Chemotaxis signal transduction systems are common in the archaeal and bacterial world, but not all systems contain the same components. The rationale for this system variation remains unknown. In this report, comparative genomics analysis showed that the presence/absence of CheR and CheB is one main variation within the Helicobacter ge

Background: Despite the fact that Helicobacter spp. has been detected in equine gastric mucosa, no evidence exists about this infection in Colombian horses affected by equine ulcerative gastric syndrome (EGUS), nor in dental tartar. Objective: To detect Helicobacter spp. DNA in equine gastric mucosa and dental tartar and determine the relationship between the presence of Helicobacter spp. and gastric lesions. Methods: Samples of glandular gastric mucosa and dental tartar were collected from 30 equine slaughterhouses. Macroscopic lesions of the stomachs were classified and the total DNA in all samples was extracted using a commercial extraction kit. A final-point PCR was performed using primers for amplification of a segment of 251 bp of the gene encoding the 16s rRNA region; the amplified fragments were subjected to a second PCR to determine the presence of H. pylori, the VacA gene was typified. The resulting amplicons were sequenced. Results: It was possible to amplify 16s rRNA in several samples but there was no amplification of VacA. Fragments of the sequences were compatible with H. heilmannii. The 23.3 and 10% of gastric and tartar samples were positive for 16s rRNA of Helicobacter spp., respectively. Conclusion: Although genetic material of Helicobacter spp. was found in some animals, there was no relationship with gastric lesions. It is possible that helicobacteriosis has no bearing in EGUS etiology., Antecedentes: Apesar do Helicobacter spp. ter sido detectado na mucosa gástrica de equinos, não há evidências dessa infecção em cavalos crioulos colombianos afetados pela síndrome ulcerativa gástrica (SUGE), ou no sarro. Objetivo: Detectar ADN de Helicobacter spp. na mucosa gástrica e do sarro dental de equinos, e determinar a relação entre a presença de Helicobacter spp. e lesões gástricas. Métodos: Amostras de mucosa gástrica glandular e sarro dental foram coletadas de 30 equinos de abatedouro, as lesões macroscópicas dos estômagos foram classificadas. Se realizou extração de ADN total em todas as amostras através de kit comercial. Realizou-se PCR ponto final, amplificando o segmento de 251 pb do gene que codifica para a região 16s ARNr; os fragmentos amplificados foram sometidos novamente a PCR para determinar a presença de H. pylori, ao tipificar o gene VacA, e seguidamente foram sequenciados. Resultados: O houve amplificação do 16s ARNr em várias amostras, mas não amplificação de VacA. Fragmentos das sequencias foram compatíveis com H. heilmannii. O 23,3 e 10% das amostras gástricas e do sarro foram positivas para 16s ARNr de Helicobacter, respectivamente. Conclusão: Embora material genético de Helicobacter spp. encontrou-se em algumos animais não houve relação com lesões gástricas. Possivelmente a helicobacterioses não tem papel relevante na etiologia da SUGE., Antecedentes: A pesar de que se ha detectado Helicobacter spp. en mucosa gástrica equina, no existe evidencia de esta infección en caballos criollos colombianos afectados por síndrome ulcerativo gástrico (SUGE), ni tampoco reportes en sarro dental. Objetivo: Detectar ADN de Helicobacter spp. en sarro dental y mucosa gástrica de equinos, y determinar la relación entre la presencia de la bacteria y lesiones gástricas. Métodos: Las muestras de mucosa glandular gástrica y sarro dental fueron colectadas de 30 equinos que se encontraban en planta de beneficio. Las lesiones macroscópicas fueron clasificadas y el ADN total de las muestras fue extraído utilizando un kit comercial. Se desarrolló PCR convencional usando cebadores específicos para la amplificación de un segmento de 251 pb de un gen que codifica la región 16S del ARNr; los fragmentos amplificados fueron sometidos a una segunda PCR para determinar la presencia de H. pylori mediante la amplificación del gen VacA. Los amplificados resultantes fueron secuenciados. Resultados: Fue posible amplificar 16s ARNr en varias muestras, pero no hubo amplificación de VacA. Los fragmentos de las secuencias fueron compatibles con H. heilmannii. El 23,3 y 10% de las muestras gástricas y sarro fueron positivas para 16s ARNr de Helicobacter spp., respectivamente. Conclusión: Aunque el material genético de Helicobacter spp. se encontró en algunos animales, no hubo relación con las lesiones gástricas. Es posible que la helicobacteriosis no tenga incidencia en la etiología del EGUS.

This case documents a previously undescribed presentation of Helicobacter spp. gastritis. An 8-year-old female spayed golden retriever with chronic vomiting was found to have a cluster of multiple, round, well-defined, hypoechoic foci of varying sizes surrounded by gas within the lumen of the stomach on ultrasonographic examination. Further endoscopic examination revealed multiple raised mass-like lesions in the fundus on endoscopic examination. Histopathological findings were consistent with Helicobacter spp. infection. The dog was treated with both amoxicillin 400 mg and clarithromycin 180 mg BID for 21 days and omeprazole 20 mg SID for 34 days. After the treatment, the vomiting and fundic lesions were resolved on ultrasonographic examination. This case represents a novel gross morphologic presentation for Helicobacter spp. gastritis that responded to appropriate therapy and highlights how early intervention with advanced imaging can aid in diagnosis and treatment.

Helicobacter pylori (H. pylori) is widely recognised as one of the most prevalent human pathogens, which infects more than 50% of the population worldwide. Chronic inflammation of the gastric mucosa is one of the main consequences of this infection and is related to the risk of developing gastric cancer. Currently, due to the high association between H. pylori infection and the progression of gastric cancer, most therapeutic treatments aim to eradicate the bacteria using different antibiotics in combination with a proton pump inhibitor in triple or quadruple therapy. However, resistant strains have increased significantly, requiring new therapeutic tools. Blueberries are rich in different bioactive compounds with antibacterial and anti-inflammatory properties that could contribute to reducing the problems associated with H. pylori infection. The aim of this research was to analyse the antibacterial and anti-inflammatory properties of different blueberry extracts (from Bluejay, Berkley, and Bluecrop varieties) obtained by different drying methods (freeze-drying (FD), vacuum drying at 50 °C, 70 °C and 90 °C (VD), and spray drying (SD)) against H. pylori infection. The results showed that all blueberry extracts exhibited antibacterial effects against H. pylori, with some of these extracts being bactericidal, while the rest reduced bacterial growth by more than 5 log CFU/mL. The Bluecrop extracts were the most active because all the extracts obtained by the different drying methods were bactericidal. The extracts obtained by vacuum drying (VD) at 50ºC were the most effective since the extracts of the three varieties were bactericidal. Regarding anti-inflammatory activity, all blueberry extracts reduced IL-8 secretion in the H. pylori-infected gastric cells. The Bluecrop extracts obtained by VD at 70 °C and 90 °C reduced IL-8 production by 30% and 32%, respectively. These results suggest that the blueberry extracts used in the present work and obtained by different dryin

Introduction: the primary goal of this study was to com pare gastrointestinal symptom reduction in patients on bismuth-containing quadruple eradication therapy sup plemented with Lactobacillus reuteri strains (DSM 17938 and ATCC PTA 6475) or placebo. Materials and methods: this was a randomized, dou ble-blind, parallel-arm, placebo-controlled clinical trial. Patients received a first-line eradication regimen based on bismuth subcitrate potassium, metronidazole, tetracycline hydrochloride (three-in-one capsules) and omeprazole 40 mg twice a day for ten days, plus a probiotic or placebo tablet for 30 days. During follow-up, gastrointestinal symp toms were assessed using an evaluation scale (GSRS), and adverse events were collected at 0, 14, 28 and 56 days. Results: a total of 80 patients were included from Febru ary 2018 to May 2019 at a single site. Eradication thera py was effective in 85 % of patients, with no differences between treatment arms. In the group receiving the probi otic, abdominal pain decreased in 42 % of patients, com pared with 19 % in the control group (OR: 0.27; CI, 0.13-0.58; p < 0.001), and abdominal distension decreased in 25 % versus 17 % in the control group (OR: 0.24; IC, 0.19-0.84; p < 0.001); Conclusions: treatment with L. reuteri only reduced abdominal pain and distension. Further studies are needed to establish the role of probiotics as adjuvant therapy in H. pylori eradication.

[ES] En el contexto actual, en el que los alimentos ecológicos y la producción agraria sostenible es un asunto prioritario, urge aumentar nuestro conocimiento sobre la seguridad microbiológica de este tipo de alimentos, tratados con fertilizantes orgánicos y con menos plaguicidas. Se suele considerar que los alimentos orgánicos son sanos y respetuosos con el medio ambiente, ya que presentan menores niveles de metales pesados o compuestos fenólicos, y más minerales, vitaminas o polifenoles. No obstante, por su modo de producción, tanto frutas como vegetales orgánicos están más expuestos a microorganismos patógenos, algunos de ellos emergentes y de riesgo poco caracterizado o subestimado. Entre estos patógenos emergentes se encuentra H. pylori, uno de los agentes más prevalentes en todo el mundo, causa de enfermedades gastrointestinales y cancerosas. También Arcobacter supone potencial riesgo para la salud pública. Para ambas bacterias existe muy escasa información disponible sobre su potencial transmisión por alimentos vegetales. Las bacterias del género Arcobacter son bacilos Gram negativos curvos que pueden crecer entre 15 y 42 grados, en condiciones tanto aerobias como anaerobias, aunque su crecimiento óptimo se da en condiciones de microaerofilia (3-10 % O2). Actualmente, el género consta de unas 17 especies reconocidas entre las cuales figuran Arcobacter butzleri o A. cryaerophilus. Su transmisión, tanto por vía hídrica como a través de los alimentos, se ve favorecida por características propias de la bacteria que la hacen resistente a ambientes adversos, incluyendo su tolerancia a altas concentraciones de hipoclorito de sodio, a metales pesados o a su capacidad de crecer a bajas temperaturas. Helicobacter pylori es un microorganismo Gram negativo microaerófilo de difícil cultivo, que presenta morfología curvada en condiciones óptimas de cultivo. Se ha sugerido que la contaminación de verduras con H. pylori y la posterior introducción de estas verduras crudas en, [EN] In the current context, in which organic food and sustainable agricultural production is a priority issue, it is urgent to increase our knowledge about the microbiological safety of this type of food, treated with organic fertilizers and with fewer pesticides. Organic food is generally considered to be healthy and respectful with the environment, since it contains lower levels of heavy metals or phenolic compounds, and more minerals, vitamins or polyphenols. However, due to their mode of production, both organic fruits and vegetables are more exposed to pathogenic microorganisms, some of them emerging and with little characterized or underestimated risk. Among these emerging pathogens is H. pylori, one of the most prevalent agents worldwide, causing gastrointestinal and cancerous diseases. Arcobacter also poses a potential risk to public health. For both bacteria there is very little information available on their potential transmission by plant foods. Bacteria of the genus Arcobacter are curved Gram negative rods that can grow between 15 and 42 degrees, under both aerobic and anaerobic conditions, although their optimal growth occurs under microaerophilic conditions (3-10% O2). Currently, the genus consists of about 17 recognized species, including Arcobacter butzleri or A. cryaerophilus. Its transmission, both by water and through food, is favored by characteristics of the bacteria that make it resistant to adverse environments, including its tolerance to high concentrations of sodium hypochlorite, heavy metals or its ability to grow. at low temperatures. Helicobacter pylori is a difficult-to-culture, Gram-negative microaerophilic microorganism that presents curved morphology under optimal culture conditions. Contamination of vegetables with H. pylori and the subsequent introduction of these raw vegetables into the food chain has been suggested as one of the routes of transmission of the bacteria to humans, and different authors have found sample rates of lea

[ES] En el contexto actual, en el que los alimentos ecológicos y la producción agraria sostenible es un asunto prioritario, urge aumentar nuestro conocimiento sobre la seguridad microbiológica de este tipo de alimentos, tratados con fertilizantes orgánicos y con menos plaguicidas. Se suele considerar que los alimentos orgánicos son sanos y respetuosos con el medio ambiente, ya que presentan menores niveles de metales pesados o compuestos fenólicos, y más minerales, vitaminas o polifenoles. No obstante, por su modo de producción, tanto frutas como vegetales orgánicos están más expuestos a microorganismos patógenos, algunos de ellos emergentes y de riesgo poco caracterizado o subestimado. Entre estos patógenos emergentes se encuentra H. pylori, uno de los agentes más prevalentes en todo el mundo, causa de enfermedades gastrointestinales y cancerosas. También Arcobacter supone potencial riesgo para la salud pública. Para ambas bacterias existe muy escasa información disponible sobre su potencial transmisión por alimentos vegetales. Las bacterias del género Arcobacter son bacilos Gram negativos curvos que pueden crecer entre 15 y 42 grados, en condiciones tanto aerobias como anaerobias, aunque su crecimiento óptimo se da en condiciones de microaerofilia (3-10 % O2). Actualmente, el género consta de unas 17 especies reconocidas entre las cuales figuran Arcobacter butzleri o A. cryaerophilus. Su transmisión, tanto por vía hídrica como a través de los alimentos, se ve favorecida por características propias de la bacteria que la hacen resistente a ambientes adversos, incluyendo su tolerancia a altas concentraciones de hipoclorito de sodio, a metales pesados o a su capacidad de crecer a bajas temperaturas. Helicobacter pylori es un microorganismo Gram negativo microaerófilo de difícil cultivo, que presenta morfología curvada en condiciones óptimas de cultivo. Se ha sugerido que la contaminación de verduras con H. pylori y la posterior introducción de estas verduras crudas en, [EN] In the current context, in which organic food and sustainable agricultural production is a priority issue, it is urgent to increase our knowledge about the microbiological safety of this type of food, treated with organic fertilizers and with fewer pesticides. Organic food is generally considered to be healthy and respectful with the environment, since it contains lower levels of heavy metals or phenolic compounds, and more minerals, vitamins or polyphenols. However, due to their mode of production, both organic fruits and vegetables are more exposed to pathogenic microorganisms, some of them emerging and with little characterized or underestimated risk. Among these emerging pathogens is H. pylori, one of the most prevalent agents worldwide, causing gastrointestinal and cancerous diseases. Arcobacter also poses a potential risk to public health. For both bacteria there is very little information available on their potential transmission by plant foods. Bacteria of the genus Arcobacter are curved Gram negative rods that can grow between 15 and 42 degrees, under both aerobic and anaerobic conditions, although their optimal growth occurs under microaerophilic conditions (3-10% O2). Currently, the genus consists of about 17 recognized species, including Arcobacter butzleri or A. cryaerophilus. Its transmission, both by water and through food, is favored by characteristics of the bacteria that make it resistant to adverse environments, including its tolerance to high concentrations of sodium hypochlorite, heavy metals or its ability to grow. at low temperatures. Helicobacter pylori is a difficult-to-culture, Gram-negative microaerophilic microorganism that presents curved morphology under optimal culture conditions. Contamination of vegetables with H. pylori and the subsequent introduction of these raw vegetables into the food chain has been suggested as one of the routes of transmission of the bacteria to humans, and different authors have found sample rates of lea

[ES] En el contexto actual, en el que los alimentos ecológicos y la producción agraria sostenible es un asunto prioritario, urge aumentar nuestro conocimiento sobre la seguridad microbiológica de este tipo de alimentos, tratados con fertilizantes orgánicos y con menos plaguicidas. Se suele considerar que los alimentos orgánicos son sanos y respetuosos con el medio ambiente, ya que presentan menores niveles de metales pesados o compuestos fenólicos, y más minerales, vitaminas o polifenoles. No obstante, por su modo de producción, tanto frutas como vegetales orgánicos están más expuestos a microorganismos patógenos, algunos de ellos emergentes y de riesgo poco caracterizado o subestimado. Entre estos patógenos emergentes se encuentra H. pylori, uno de los agentes más prevalentes en todo el mundo, causa de enfermedades gastrointestinales y cancerosas. También Arcobacter supone potencial riesgo para la salud pública. Para ambas bacterias existe muy escasa información disponible sobre su potencial transmisión por alimentos vegetales. Las bacterias del género Arcobacter son bacilos Gram negativos curvos que pueden crecer entre 15 y 42 grados, en condiciones tanto aerobias como anaerobias, aunque su crecimiento óptimo se da en condiciones de microaerofilia (3-10 % O2). Actualmente, el género consta de unas 17 especies reconocidas entre las cuales figuran Arcobacter butzleri o A. cryaerophilus. Su transmisión, tanto por vía hídrica como a través de los alimentos, se ve favorecida por características propias de la bacteria que la hacen resistente a ambientes adversos, incluyendo su tolerancia a altas concentraciones de hipoclorito de sodio, a metales pesados o a su capacidad de crecer a bajas temperaturas. Helicobacter pylori es un microorganismo Gram negativo microaerófilo de difícil cultivo, que presenta morfología curvada en condiciones óptimas de cultivo. Se ha sugerido que la contaminación de verduras con H. pylori y la posterior introducción de estas verduras crudas en, [EN] In the current context, in which organic food and sustainable agricultural production is a priority issue, it is urgent to increase our knowledge about the microbiological safety of this type of food, treated with organic fertilizers and with fewer pesticides. Organic food is generally considered to be healthy and respectful with the environment, since it contains lower levels of heavy metals or phenolic compounds, and more minerals, vitamins or polyphenols. However, due to their mode of production, both organic fruits and vegetables are more exposed to pathogenic microorganisms, some of them emerging and with little characterized or underestimated risk. Among these emerging pathogens is H. pylori, one of the most prevalent agents worldwide, causing gastrointestinal and cancerous diseases. Arcobacter also poses a potential risk to public health. For both bacteria there is very little information available on their potential transmission by plant foods. Bacteria of the genus Arcobacter are curved Gram negative rods that can grow between 15 and 42 degrees, under both aerobic and anaerobic conditions, although their optimal growth occurs under microaerophilic conditions (3-10% O2). Currently, the genus consists of about 17 recognized species, including Arcobacter butzleri or A. cryaerophilus. Its transmission, both by water and through food, is favored by characteristics of the bacteria that make it resistant to adverse environments, including its tolerance to high concentrations of sodium hypochlorite, heavy metals or its ability to grow. at low temperatures. Helicobacter pylori is a difficult-to-culture, Gram-negative microaerophilic microorganism that presents curved morphology under optimal culture conditions. Contamination of vegetables with H. pylori and the subsequent introduction of these raw vegetables into the food chain has been suggested as one of the routes of transmission of the bacteria to humans, and different authors have found sample rates of lea

[ES] En el contexto actual, en el que los alimentos ecológicos y la producción agraria sostenible es un asunto prioritario, urge aumentar nuestro conocimiento sobre la seguridad microbiológica de este tipo de alimentos, tratados con fertilizantes orgánicos y con menos plaguicidas. Se suele considerar que los alimentos orgánicos son sanos y respetuosos con el medio ambiente, ya que presentan menores niveles de metales pesados o compuestos fenólicos, y más minerales, vitaminas o polifenoles. No obstante, por su modo de producción, tanto frutas como vegetales orgánicos están más expuestos a microorganismos patógenos, algunos de ellos emergentes y de riesgo poco caracterizado o subestimado. Entre estos patógenos emergentes se encuentra H. pylori, uno de los agentes más prevalentes en todo el mundo, causa de enfermedades gastrointestinales y cancerosas. También Arcobacter supone potencial riesgo para la salud pública. Para ambas bacterias existe muy escasa información disponible sobre su potencial transmisión por alimentos vegetales. Las bacterias del género Arcobacter son bacilos Gram negativos curvos que pueden crecer entre 15 y 42 grados, en condiciones tanto aerobias como anaerobias, aunque su crecimiento óptimo se da en condiciones de microaerofilia (3-10 % O2). Actualmente, el género consta de unas 17 especies reconocidas entre las cuales figuran Arcobacter butzleri o A. cryaerophilus. Su transmisión, tanto por vía hídrica como a través de los alimentos, se ve favorecida por características propias de la bacteria que la hacen resistente a ambientes adversos, incluyendo su tolerancia a altas concentraciones de hipoclorito de sodio, a metales pesados o a su capacidad de crecer a bajas temperaturas. Helicobacter pylori es un microorganismo Gram negativo microaerófilo de difícil cultivo, que presenta morfología curvada en condiciones óptimas de cultivo. Se ha sugerido que la contaminación de verduras con H. pylori y la posterior introducción de estas verduras crudas en, [EN] In the current context, in which organic food and sustainable agricultural production is a priority issue, it is urgent to increase our knowledge about the microbiological safety of this type of food, treated with organic fertilizers and with fewer pesticides. Organic food is generally considered to be healthy and respectful with the environment, since it contains lower levels of heavy metals or phenolic compounds, and more minerals, vitamins or polyphenols. However, due to their mode of production, both organic fruits and vegetables are more exposed to pathogenic microorganisms, some of them emerging and with little characterized or underestimated risk. Among these emerging pathogens is H. pylori, one of the most prevalent agents worldwide, causing gastrointestinal and cancerous diseases. Arcobacter also poses a potential risk to public health. For both bacteria there is very little information available on their potential transmission by plant foods. Bacteria of the genus Arcobacter are curved Gram negative rods that can grow between 15 and 42 degrees, under both aerobic and anaerobic conditions, although their optimal growth occurs under microaerophilic conditions (3-10% O2). Currently, the genus consists of about 17 recognized species, including Arcobacter butzleri or A. cryaerophilus. Its transmission, both by water and through food, is favored by characteristics of the bacteria that make it resistant to adverse environments, including its tolerance to high concentrations of sodium hypochlorite, heavy metals or its ability to grow. at low temperatures. Helicobacter pylori is a difficult-to-culture, Gram-negative microaerophilic microorganism that presents curved morphology under optimal culture conditions. Contamination of vegetables with H. pylori and the subsequent introduction of these raw vegetables into the food chain has been suggested as one of the routes of transmission of the bacteria to humans, and different authors have found sample rates of lea

Helicobacter pylori (H. pylori) infection is a major risk factor for the development of gastric cancer. The authors previously demonstrated that in mice deficient in myeloid differentiation primary response 88 (Myd88‑/‑), infection with Helicobacter felis (H. felis) a close relative of H. pylori, subsequently rapidly progressed to neoplasia. The present study examined circulating tumor cells (CTCs) by measuring the expression of cytokeratins, epithelial‑to‑mesenchymal transition (EMT)‑related markers and cancer stem cell (CSC) markers in bone marrow and peripheral blood from Myd88‑/‑ and wild‑type (WT) mice. Cytokeratins CK8/18 were detected as early as 4 months post‑infection in Myd88‑/‑ mice. By contrast, cytokeratins were not detected in WT mice even after 7 months post‑infection. The expression of Mucin‑1 (MUC1) was observed in both bone marrow and peripheral blood at different time points, suggesting its role in gastric cancer metastasis. Snail, Twist and ZEB were expressed at different levels in bone marrow and peripheral blood. The expression of these EMT‑related markers suggests the manifestation of cancer metastasis in the early stages of disease development. LGR5, CD44 and CD133 were the most prominent CSC markers detected. The detection of CSC and EMT markers along with cytokeratins does reinforce their use as biomarkers for gastric cancer metastasis. This early detection of markers suggests that CTCs leave primary site even before cancer is well established. Thus, cytokeratins, EMT, and CSCs could be used as biomarkers to detect aggressive forms of gastric cancers. This information may prove to be of significance in stratifying patients for treatment prior to the onset of severe disease‑related characteristics.

En el presente artículo, se hace una revisión sobre los aspectos básicos del tratamiento de Helicobacter pylori, destacando las causas de la falla del tratamiento y se dan estrategias para optimizar el tratamiento de acuerdo a la mejor evidencia publicada. Se destaca la resistencia a los antimicrobianos como la principal causa de fracaso terapéutico, así como también los diferentes compartimentos donde se aloja el microrganismo. Se muestran los principales esquemas actualmente disponibles y la forma de elegir las terapias de primera, segunda, tercera línea y terapias de rescate.

Antimicrobial resistant (AMR) bacteria constitute a global health concern. Helicobacter pylori is a Gram-negative bacterium that infects about half of the human population and is a major cause of peptic ulcer disease and gastric cancer. Increasing resistance to triple and quadruple H. pylori eradication therapies poses great challenges and urges the development of novel, ideally narrow spectrum, antimicrobials targeting H. pylori. Here, we describe the antimicrobial spectrum of a family of nitrobenzoxadiazol-based antimicrobials initially discovered as inhibitors of flavodoxin: an essential H. pylori protein. Two groups of inhibitors are described. One group is formed by narrow-spectrum compounds, highly specific for H. pylori, but ineffective against enterohepatic Helicobacter species and other Gram-negative or Gram-positive bacteria. The second group includes extended-spectrum antimicrobials additionally targeting Gram-positive bacteria, the Gram-negative Campylobacter jejuni, and most Helicobacter species, but not affecting other Gram-negative pathogens. To identify the binding site of the inhibitors in the flavodoxin structure, several H. pylori-flavodoxin variants have been engineered and tested using isothermal titration calorimetry. An initial study of the inhibitors capacity to generate resistances and of their synergism with antimicrobials commonly used in H. pylori eradication therapies is described. The narrow-spectrum inhibitors, which are expected to affect the microbiota less dramatically than current antimicrobial drugs, offer an opportunity to develop new and specific H. pylori eradication combinations to deal with AMR in H. pylori. On the other hand, the extended-spectrum inhibitors constitute a new family of promising antimicrobials, with a potential use against AMR Gram-positive bacterial pathogens.

Chronic Helicobacter pylori colonization in animal models often leads to downregulation of the type IV secretion system (T4SS), typically by recombination in cagY, which is an essential T4SS gene. However, 17 other cag pathogenicity island (cagPAI) genes, as well as some non-cagPAI genes, are also essential for T4SS function. To get a more complete picture of how H. pylori regulates the T4SS during animal colonization, we examined cagY in 534 mouse-passaged isolates that lost T4SS function, defined as a normalized interleukin-8 (IL-8) value of <0.3 relative to the input H. pylori strain PMSS1. In order to analyze the genetic changes in the strains with unchanged cagY, we sequenced the entire pathogenicity island of 60 such isolates using single-molecule, real-time (SMRT) sequencing technology (PacBio, Menlo Park, CA), and we compared the results to the PMSS1 wild type (WT). Of the 534 strains, 271 (51%) showed evidence of recombination in cagY, but we also found indels or nonsynonymous changes in 13 other essential cagPAI genes implicated in H. pylori T4SS function, most commonly cag5, cag10, and cagA While cagY recombination is the most common mechanism by which H. pylori downregulates T4SS function during murine infection, loss of function is also associated with changes in other essential cagPAI genes.

© 2020 Elsevier GmbH Two isolates, one recovered from a carrot and another one from urban wastewater, were characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that both isolates clustered together, and were most closely related to Aliarcobacter lanthieri. Multilocus phylogenetic analysis (MLPA) using the concatenated sequences of five housekeeping genes (atpA, gyrA, gyrB, hsp60 and rpoB) suggested that these isolates formed a distinct phylogenetic lineage among the genera derived from the former genus Arcobacter. Whole-genome sequence, in silico DNA-DNA hybridization (isDDH) and the average nucleotide identity (ANI) value between the genome of strain F199T and those of related species confirmed that these isolates represent a novel species. These strains can be differentiated from its phylogenetically closest species A. lanthieri by its inability to growth on 1% glycine and by their enzyme activity of esterase lipase (C8) and acid phosphatase. Our results, by the application of a polyphasic analysis, confirmed that these two isolates represent a novel species of the genus Aliarcobacter, for which the name Aliarcobacter vitoriensis sp. nov. is proposed. The type strain is F199T (=CECT 9230T=LMG 30050T).

Species of the Epsilonproteobacteria genera Arcobacter, Campylobacter, and Helicobacter are commonly associated with vertebrate hosts and some are considered significant pathogens. Vertebrate-associated Epsilonproteobacteria are often considered to be largely confined to endothermic mammals and birds. Recent studies have shown that ectothermic reptiles display a distinct and largely unique Epsilonproteobacteria community, including taxa which can cause disease in humans. Several Arcobacter taxa are widespread amongst reptiles and often show a broad host range. Reptiles carry a large diversity of unique and novel Helicobacter taxa, which apparently evolved in an ectothermic host. Some species, such as Campylobacter fetus, display a distinct intraspecies host dichotomy, with genetically divergent lineages occurring either in mammals or reptiles. These taxa can provide valuable insights in host adaptation and co-evolution between symbiont and host. Here, we present an overview of the biodiversity, ecology, epidemiology, and evolution of reptile-associated Epsilonproteobacteria from a broader vertebrate host perspective.

Species of the Epsilonproteobacteria genera Arcobacter, Campylobacter, and Helicobacter are commonly associated with vertebrate hosts and some are considered significant pathogens. Vertebrate-associated Epsilonproteobacteria are often considered to be largely confined to endothermic mammals and birds. Recent studies have shown that ectothermic reptiles display a distinct and largely unique Epsilonproteobacteria community, including taxa which can cause disease in humans. Several Arcobacter taxa are widespread amongst reptiles and often show a broad host range. Reptiles carry a large diversity of unique and novel Helicobacter taxa, which apparently evolved in an ectothermic host. Some species, such as Campylobacter fetus, display a distinct intraspecies host dichotomy, with genetically divergent lineages occurring either in mammals or reptiles. These taxa can provide valuable insights in host adaptation and co-evolution between symbiont and host. Here, we present an overview of the biodiversity, ecology, epidemiology, and evolution of reptile-associated Epsilonproteobacteria from a broader vertebrate host perspective.

While it is known that Helicobacter species in humans and ferrets can cause gastritis and gastric ulcers, it is unknown if the sea otter bacterium, ‘H. enhydrae’ sp. nov., causes similar gastric diseases. Southern sea otters (Enhydra lutris nereis) are marine mustelids that commonly have gastric ulcers as a significant contributing cause of death. Determining whether Helicobacter infection promotes gastric diseases might aid population recovery by recognizing disease presentation and facilitating treatments. As a first step, we investigated the prevalence of Helicobacter infections in southern sea otters using DNA. Helicobacter DNA was amplified using quantitative polymerase chain reaction from formalin-fixed and fresh-frozen gastric body and pyloric tissues from 46 sea otters using Helicobacter genus 16S rRNA primers. Postmortem examination data and histology were statistically analyzed to uncover associations between Helicobacter presence and gastric diseases. Enrolled sea otters had an 85% Helicobacter spp. prevalence, which is comparable to H. mustelae in ferrets. Fresh frozen tissues showed a higher amount of Helicobacter qPCR-positive samples than did formalin-fixed tissues. Gastric ulcers at the postmortem exam were significantly associated with Helicobacter positivity, while other analyzed factors such as sex, melena, and shark trauma were not correlated. Antibiotic sensitivity analysis show that ‘H. enhydrae’ was sensitive to tetracycline and clarithromycin in vitro. Our data suggest that Helicobacter infections are prevalent in southern sea otters and are associated with gastric ulcers. Our data represents a first step in the study of this potential pathogen, supporting that further work is warranted to assess whether ‘H. enhydrae’ causes or is simply associated with gastric ulcers.

Macrophages play an important role in the generation of host immune responses against H. pylori. In this study, we investigated the effect of a functionally uncharacterized H. pylori secreted protein HP1173 on macrophage responses. In a screen of eight H. pylori strains, similar expression levels of the HP1173 protein were observed in the whole-cell extracts, however; the amount of protein released into the culture medium varied significantly among strains. Recombinant purified HP1173 (rHP1173) was found to bind to THP-1 cells that were differentiated into macrophages via phorbol-12-myristate-13-acetate (PMA) treatment. The exposure of macrophages to rHP1173 led to the production of the proinflammatory cytokines TNF and IL-1 beta and the chemokine CXCL8 in a dose- and time-dependent manner. Under similar conditions, rHP1173 failed to induce apoptosis in macrophages. Furthermore, rHP1173-induced expression of TNF, IL-1 beta and CXCL8 was observed at the level of gene transcription. Incubation of macrophages in the conditioned medium from a mutant H. pylori strain 26695 lacking HP1173 protein expression resulted in the reduced induction of TNF, CXCL8 and IL-1 beta, confirming the role of the endogenous protein. Intracellular signaling involving MAPKs, NF-kappa B and the AP-1 family of transcription factors was required for rHP1173-induced TNF, CXCL8 and IL-1 beta release from macrophages. The blocking of MyD88, which is an adaptor for multiple toll-like receptors (TLRs), had no effect on rHP1173-induced TNF, CXCL8 and IL-1 beta release from macrophages, suggesting that Myd88-dependent TLR signaling was not involved in the recognition of and responses to rHP1173. These findings provide novel insights into the potential role of HP1173 in H. pylori infection-associated disease development.

While it is known that Helicobacter species in humans and ferrets can cause gastritis and gastric ulcers, it is unknown if the sea otter bacterium, ‘H. enhydrae’ sp. nov., causes similar gastric diseases. Southern sea otters (Enhydra lutris nereis) are marine mustelids that commonly have gastric ulcers as a significant contributing cause of death. Determining whether Helicobacter infection promotes gastric diseases might aid population recovery by recognizing disease presentation and facilitating treatments. As a first step, we investigated the prevalence of Helicobacter infections in southern sea otters using DNA. Helicobacter DNA was amplified using quantitative polymerase chain reaction from formalin-fixed and fresh-frozen gastric body and pyloric tissues from 46 sea otters using Helicobacter genus 16S rRNA primers. Postmortem examination data and histology were statistically analyzed to uncover associations between Helicobacter presence and gastric diseases. Enrolled sea otters had an 85% Helicobacter spp. prevalence, which is comparable to H. mustelae in ferrets. Fresh frozen tissues showed a higher amount of Helicobacter qPCR-positive samples than did formalin-fixed tissues. Gastric ulcers at the postmortem exam were significantly associated with Helicobacter positivity, while other analyzed factors such as sex, melena, and shark trauma were not correlated. Antibiotic sensitivity analysis show that ‘H. enhydrae’ was sensitive to tetracycline and clarithromycin in vitro. Our data suggest that Helicobacter infections are prevalent in southern sea otters and are associated with gastric ulcers. Our data represents a first step in the study of this potential pathogen, supporting that further work is warranted to assess whether ‘H. enhydrae’ causes or is simply associated with gastric ulcers.

Macrophages constitute a powerful line of defense against H. pylori. The final disease outcome is highly dependent on the bacterial ability to modulate the effector functions of activated macrophages. Here, we report that H. pylori secreted protein HP1286 is a novel regulator of macrophage responses. Differential expression and release of HP1286 homologues were observed among H. pylori strains. Recombinant purified HP1286 ( rHP1286) had the ability to bind to primary human monocyte-derived macrophages ( MDM) and macrophage cell lines. Exposure to rHP1286 induced apoptosis in macrophages in a dose-and time-dependent manner. Although interaction of rHP1286 was observed for several other cell types, such as human monocytes, differentiated neutrophil-like HL60 cells, and the T lymphocyte Jurkat cell line, rHP1286 failed to induce apoptosis under similar conditions, indicating a macrophage-specific effect of the protein. A mutant strain of H. pylori lacking HP1286 protein expression was significantly impaired in its ability to induce apoptosis inmacrophages. Significantly higher caspase 3 activity was detected in rHP1286-challenged macrophages. Furthermore, rHP1286-induced macrophages apoptosis was not inhibited in the presence of neutralizing antibodies against TNF. These observations indicate that rHP1286 induced a caspase-dependent and TNF-independent macrophage apoptosis. Pre-treatment of macrophages with U0126, an inhibitor of the ERK MAPK signaling pathway significantly reduced rHP1286-induced apoptosis. Furthermore, nuclear translocation of ERK and phosphorylation of c-Fos was detected in rHP1286-treated macrophages. These results provide functional insight into the potential role of HP1286 during H. pylori infection. Considering the ability of HP1286 to induce macrophage apoptosis, the protein could possibly help in the bacterial escape from the activated macrophages and persistence in the stomach.

BackgroundGastric cancer is one of the most common and lethal type of cancer worldwide. Infection with Helicobacter pylori (H. pylori) is recognized as the major cause of gastric cancer. However, it remains unclear the mechanism by which Helicobacter infection leads to gastric cancer. Furthermore, the underlying molecular events involved during the progression of Helicobacter infection to gastric malignancy are not well understood. In previous studies, we demonstrated that that H. felis-infected Myd88 -/- mice exhibited dramatic pathology and an accelerated progression to gastric dysplasia; however, the MyD88 downstream gene targets responsible for this pathology have not been described. This study was designed to identify MyD88-dependent genes involved in the progression towards gastric cancer during the course of Helicobacter infection.MethodsWild type (WT) and Myd88 deficient mice (Myd88 -/-) were infected with H. felis for 25 and 47 weeks and global transcriptome analysis performed on gastric tissue using MouseWG-6 v2 expression BeadChips microarrays. Function and pathway enrichment analyses of statistically significant, differential expressed genes (p < 0.05) were performed using the Database for Annotation, Visualization and Integrated Discovery (DAVID) online tools.ResultsHelicobacter infection affected the transcriptional profile of more genes in Myd88 -/- mice compared to WT mice. Infection of Myd88 -/- mice resulted in the differential expression of 1,989 genes at 25 weeks (1031 up and 958 downregulated). At 47 weeks post-H.felis infection, 2,162 (1140 up and 1022 downregulated) were differentially expressed. The most significant differentially upregulated gene during Helicobacter infection in Myd88 -/- mice was chitinase-like 4 (chil4), which is involved in tissue remodeling and wound healing. Other highly upregulated genes in H. felis-infected Myd88 -/- mice included, Indoleamine 2,3-Dioxygenase 1 (Ido1), Guanylate binding protein 2 (Gb

Mucispirillum schaedleri is an abundant inhabitant of the intestinal mucus layer of rodents and other animals and has been suggested to be a pathobiont, a commensal that plays a role in disease. In order to gain insights into its lifestyle, we analyzed the genome and transcriptome of M. schaedleri ASF 457 and performed physiological experiments to test traits predicted by its genome. Although described as a mucus inhabitant, M. schaedleri has limited capacity for degrading host-derived mucosal glycans and other complex polysaccharides. Additionally, M. schaedleri reduces nitrate and expresses systems for scavenging oxygen and reactive oxygen species in vivo, which may account for its localization close to the mucosal tissue and expansion during inflammation. Also of note, M. schaedleri harbors a type VI secretion system and putative effector proteins and can modify gene expression in mucosal tissue, suggesting intimate interactions with its host and a possible role in inflammation. The M. schaedleri genome has been shaped by extensive horizontal gene transfer, primarily from intestinal Epsilon- and Deltaproteobacteria, indicating that horizontal gene transfer has played a key role in defining its niche in the gut ecosystem.

Helicobacter pylori occupies a prominent position among emerging human pathogens, one of the most common causes of chronic bacterial infection in humanity and closely linked to peptic ulcers and gastric cancer. It has been suggested that H.pylori can be acquired by different routes of transmission, including water. The growing demand for water due to increasing world population and the concurrent expansion of the industry necessitates the use of treated wastewater. However, H. pylori resistance to water disinfection treatment constitutes a risk to health. Similarly, H.pylori has resilience to water purification treatments and at high concentrations of free chlorine in distribution systems by biofilm formation. The VBNC state of H.pylori in both matrices is the usual in stress conditions, necessitating the application of molecular techniques for detection and identification. In this thesis we have studied the presence and viability of this important pathogen in both wastewater and drinking water. A total of 60 wastewater samples, including samples of the biological reactor inlet, the outlet of this one and samples after tertiary ultraviolet disinfection treatment, were analyzed for the presence of H.pylori by PCR, q-PCR and FISH and the traditional cultivable technique. The FISH technique proved to be an effective and rapid method for the detection of H. pylori in waste and debugged water (61.2 %), without the need for a preliminary step enrichment of samples. The PCR and q-PCR techniques determined the presence of H. pylori in the samples, with detection rates of both 15 %. It was possible to quantify only in 3 direct samples belonging to the reactor inlet and outlet (1.8x10; 1.5x10 and 6.3x10 GU/mL), the other samples had the Ct above the threshold of reliability (> 35 cycles). Although the culture turned out to be a not fully resolutive method, the method of isolation by 0.65 µm membrane, tuned in this thesis, was effective in reducing the accompanying mi, Resumen Helicobacter pylori ocupa una posición destacada entre los patógenos humanos emergentes, siendo una de las causas más comunes de infección crónica bacteriana en la humanidad y estrechamente relacionada con la úlcera péptica y el cáncer gástrico. Se ha sugerido que H.pylori puede ser adquirido por diferentes vías de transmisión, entre ellas el agua. El aprovechamiento de las aguas residuales depuradas y la resistencia de H. pylori a los tratamientos de desinfección del agua constituye un riesgo para la salud. De igual forma, H.pylori presenta capacidad de resistencia a tratamientos de potabilización y a concentraciones elevadas de cloro libre en los sistemas de distribución gracias a la formación de biopelículas. El estado VNC de H.pylori, en ambas matrices, hace necesario la aplicación de técnicas moleculares para su detección e identificación. En esta tesis doctoral se ha estudiado la presencia y viabilidad de este importante patógeno tanto en agua residual como potable. Un total de 60 muestras de agua residual, incluyendo muestras de la entrada del reactor biológico, de la salida de éste y tras el tratamiento de desinfección con UV, se analizaron para detectar la presencia de H. pylori mediante las técnicas moleculares PCR, q-PCR y FISH y cultivo en placa. La técnica FISH resultó ser un método eficaz y rápido para la detección de H. pylori en las aguas residuales y depuradas (61.2 %), sin la necesidad de un paso previo de enriquecimiento de las muestras. Las técnicas PCR y q-PCR determinaron la presencia de H.pylori en las muestras, con porcentajes de detección de ambas del 15 %. Fue posible cuantificar únicamente en 3 muestras directas, pertenecientes a la entrada y salida del reactor (1.8x10; 1.5x10 y 6.3x10 GU/ mL). Aunque el cultivo resultó ser un método poco resolutivo, el método de aislamiento mediante membrana de 0.65 µm, puesto a punto en esta tesis doctoral, resultó eficaz para reducir la microbiota acompañante y poder obtener H.pylori cultivable, Resum Helicobacter pylori ocupa una posició destacada entre els patògens humans emergents, sent una de les causes més comuns d'infecció crònica bacteriana en la humanitat i estretament relacionada amb l'úlcera pèptica i el càncer gàstric. S'ha suggerit que H. pylori pot ser adquirit per diferents vies de transmissió, entre elles l'aigua. L'aprofitament de les aigües residuals depurades i la resistència d'H. pylori als tractaments de desinfecció de l'aigua constitueix un risc per a la salut.De la mateixa manera, H. pylori presenta capacitat de resistència a tractaments de potabilització i a concentracions elevades de clor lliure en els sistemes de distribució gràcies a la formació de biopel¿lícules. L'estat VNC de H. pylori, en ambdues matrius, fa necessari l'aplicació de tècniques moleculars per a la seva detecció i identificació. En aquesta tesi doctoral s'ha estudiat la presència i viabilitat d'aquest important patogen tant en aigua residual com potable. Un total de 60 mostres d'aigua residual, incloent mostres de l'entrada del reactor biològic, de la sortida d'aquest i després del tractament de desinfecció amb UV, es van analitzar per detectar la presència de H. pylori mitjançant les tècniques moleculars PCR, q-PCR i FISH i cultiu en placa. La tècnica FISH va resultar ser un mètode eficaç i ràpid per a la detecció de H. pylori en les aigües residuals i depurades (61.2 %), sense la necessitat d'un pas previ d'enriquiment de les mostres. Les tècniques PCR i q-PCR van determinar la presència de H. pylori en les mostres, amb percentatges de detecció de les dues del 15 %. Va ser possible quantificar únicament en 3 mostres directes, pertanyents a l'entrada i sortida del reactor (1.8x10; 1.5x10 i 6.3x10 GU/mL). Tot i que el cultiu va resultar ser un mètode poc resolutiu, el mètode d'aïllament mitjançant membrana de 0.65 µm, posat a punt en aquesta tesi doctoral, va resultar eficaç per reduir la microbiota acompanyant i poder obtenir H. pylori cultivable per primera vega

Bacteria of the Arcobacter genus are microorganisms belonging to the Campylobacteraceae family. Currently, the Arcobacter genus comprises 23 species, isolated from a variety of hosts and ecological niches. Although most of the pathogenic species are from fecal origin, seawater is considered to be the habitat for most of them. The transmission to humans seems to be associated to the consumption of raw food or not entirely-cooked. In this regard, the presence of pathogenic Arcobacter species in food of marine origin and vegetables has not been deeply studied. When the detection and identification of Arcobacter is performed exclusively using conventional culture-based methods, the process is slow, tedious and rarely effective many times, originating frequently false negatives. Molecular biology-based methods analyzing nucleic acids with the use of the Polymerase Chain Reaction (PCR), are alternative procedure characterized by being reliable, faster, more sensitive. In this thesis we have analysed the presence of Arcobacter spp in 100 samples from shellfish and another 100 samples from vegetables using both approaches, on one side through the isolation and characterization by plate culture in and on the other side by PCR. The results obtained by both methods confirm the presence of Arcobacter spp. in the samples. An enrichment period followed by PCR has proved to be more sensitive than culture for the detection of the microorganism in the samples. In this study, Arcobacter contamination has been detected in 71 % of the shellfish samples and 20 % of vegetable samples. The obtained Arcobacter isolates have been identified to the species level analyzing the 16 rRNA gene by PCR-RFLP. This technique has allowed the identification of the species A. butzleri, A. cryaerophilus and A. defluvii in the shellfish isolates, being the first time that A. defluvii is identified in clams. Additionally, it is also the first time that Arcobacter spp. is detected in cockles. A. butzleri an, Las bacterias del género Arcobacter son microorganismos pertenecientes a la familia Campylobacteraceae. Actualmente, el género Arcobacter comprende 23 especies, aisladas de una gran diversidad de hospedadores y nichos ecológicos. Las aguas de mar son consideradas el hábitat natural para muchas de ellas, aunque la mayor parte de las especies patógenas son de origen fecal. La transmisión al hombre parece estar asociada al consumo de alimentos crudos o poco cocidos. Sin embargo, la presencia de especies patógenas de Arcobacter en alimentos de origen marino y vegetales ha sido muy poco estudiada. Cuando la detección e identificación de Arcobacter, se establece exclusivamente en función de métodos convencionales de cultivo, el proceso resulta lento, tedioso y poco efectivo en muchas ocasiones, originando frecuentes falsos negativos. Los métodos de detección molecular basados en el análisis de ácidos nucleicos, como la Reacción en Cadena de la Polimerasa (PCR), pueden suponer una alternativa más rápida, sensible y fiable. Por todo ello, en este trabajo se ha realizado la detección de Arcobacter spp. mediante aislamiento por cultivo en placa y PCR, a partir de 100 muestras de moluscos y 100 de verduras. Los resultados obtenidos por ambos métodos confirman la existencia de Arcobacter en las muestras. La PCR, realizada tras un periodo de enriquecimiento, ha resultado ser más sensible que el cultivo para la detección del microorganismo en las muestras. En este trabajo se ha detectado contaminación por Arcobacter en el 71 % de las muestras de moluscos y el 20 % de las muestras de verduras. Los aislados de Arcobacter obtenidos han sido identificados a nivel de especie mediante un análisis PCR-RFLP del gen 16 ARNr. Esta técnica ha permitido identificar las especies A. butzleri, A. cryaerophilus y A. defluvii de los aislados de moluscos, siendo la primera vez que es identificada A. defluvii de muestras de almejas. También es la primera vez que se detecta Arcobacter spp. en berber, Els bacteris del gènere Arcobacter són microorganismes pertanyents a la família Campylobacteraceae. Actualment, el gènere Arcobacter comprèn 23 espècies, aïllades d'una gran diversitat d'hostes i nínxols ecològics. Les aigües de la mar són considerades l'hàbitat natural per a moltes d'aquestes espècies, encara que la major part de les patògenes són d'origen fecal. La transmissió a l'home sembla estar associada al consum d'aliments crus o poc cuits. No obstant això, la presència d'espècies patògenes d'Arcobacter en aliments d'origen marí i vegetals ha sigut molt poc estudiada. Quan la detecció i identificació d'Arcobacter s'estableix exclusivament en funció de mètodes convencionals de cultiu, el procés resulta lent, tediós i sovint poc efectiu, i origina amb freqüència falsos negatius. Els mètodes de detecció molecular basats en l'anàlisi d'àcids nucleics, com la reacció en cadena de la polimerasa (PCR), poden suposar una alternativa més ràpida, sensible i fiable. Per tot això, en aquest treball s'ha realitzat la detecció d'Arcobacter spp. mitjançant aïllament per cultiu en placa i PCR, a partir de 100 mostres de mol·luscos i 100 de verdures. Els resultats obtinguts pels dos mètodes confirmen l'existència d'Arcobacter en les mostres. La PCR, després d'un període d'enriquiment, ha resultat ser més sensible que el cultiu per a la detecció del microorganisme en mostres de mol·luscos. En aquest treball, s'ha detectat contaminació per Arcobacter en el 71 % de les mostres de mol·luscos i el 20 % de les mostres de verdures. Els aïllats d'Arcobacter obtinguts han sigut identificats a nivell d'espècie mitjançant una anàlisi PCR-RFLP del gen 16 ARNr. Aquesta tècnica ha permès identificar les espècies A. butzleri, A. cryaerophilus i A. defluvii en els aïllats de mol·luscos. Aquesta és la primera vegada que A. defluvii és identificada en mostres de cloïsses. També és la primera vegada que es detecta Arcobacter spp. en catxels. En el cas de les verdures, s'han aïllat A. butzleri

Helicobacter pylori occupies a prominent position among emerging human pathogens, one of the most common causes of chronic bacterial infection in humanity and closely linked to peptic ulcers and gastric cancer. It has been suggested that H.pylori can be acquired by different routes of transmission, including water. The growing demand for water due to increasing world population and the concurrent expansion of the industry necessitates the use of treated wastewater. However, H. pylori resistance to water disinfection treatment constitutes a risk to health. Similarly, H.pylori has resilience to water purification treatments and at high concentrations of free chlorine in distribution systems by biofilm formation. The VBNC state of H.pylori in both matrices is the usual in stress conditions, necessitating the application of molecular techniques for detection and identification. In this thesis we have studied the presence and viability of this important pathogen in both wastewater and drinking water. A total of 60 wastewater samples, including samples of the biological reactor inlet, the outlet of this one and samples after tertiary ultraviolet disinfection treatment, were analyzed for the presence of H.pylori by PCR, q-PCR and FISH and the traditional cultivable technique. The FISH technique proved to be an effective and rapid method for the detection of H. pylori in waste and debugged water (61.2 %), without the need for a preliminary step enrichment of samples. The PCR and q-PCR techniques determined the presence of H. pylori in the samples, with detection rates of both 15 %. It was possible to quantify only in 3 direct samples belonging to the reactor inlet and outlet (1.8x10; 1.5x10 and 6.3x10 GU/mL), the other samples had the Ct above the threshold of reliability (> 35 cycles). Although the culture turned out to be a not fully resolutive method, the method of isolation by 0.65 µm membrane, tuned in this thesis, was effective in reducing the accompanying mi, Resumen Helicobacter pylori ocupa una posición destacada entre los patógenos humanos emergentes, siendo una de las causas más comunes de infección crónica bacteriana en la humanidad y estrechamente relacionada con la úlcera péptica y el cáncer gástrico. Se ha sugerido que H.pylori puede ser adquirido por diferentes vías de transmisión, entre ellas el agua. El aprovechamiento de las aguas residuales depuradas y la resistencia de H. pylori a los tratamientos de desinfección del agua constituye un riesgo para la salud. De igual forma, H.pylori presenta capacidad de resistencia a tratamientos de potabilización y a concentraciones elevadas de cloro libre en los sistemas de distribución gracias a la formación de biopelículas. El estado VNC de H.pylori, en ambas matrices, hace necesario la aplicación de técnicas moleculares para su detección e identificación. En esta tesis doctoral se ha estudiado la presencia y viabilidad de este importante patógeno tanto en agua residual como potable. Un total de 60 muestras de agua residual, incluyendo muestras de la entrada del reactor biológico, de la salida de éste y tras el tratamiento de desinfección con UV, se analizaron para detectar la presencia de H. pylori mediante las técnicas moleculares PCR, q-PCR y FISH y cultivo en placa. La técnica FISH resultó ser un método eficaz y rápido para la detección de H. pylori en las aguas residuales y depuradas (61.2 %), sin la necesidad de un paso previo de enriquecimiento de las muestras. Las técnicas PCR y q-PCR determinaron la presencia de H.pylori en las muestras, con porcentajes de detección de ambas del 15 %. Fue posible cuantificar únicamente en 3 muestras directas, pertenecientes a la entrada y salida del reactor (1.8x10; 1.5x10 y 6.3x10 GU/ mL). Aunque el cultivo resultó ser un método poco resolutivo, el método de aislamiento mediante membrana de 0.65 µm, puesto a punto en esta tesis doctoral, resultó eficaz para reducir la microbiota acompañante y poder obtener H.pylori cultivable, Resum Helicobacter pylori ocupa una posició destacada entre els patògens humans emergents, sent una de les causes més comuns d'infecció crònica bacteriana en la humanitat i estretament relacionada amb l'úlcera pèptica i el càncer gàstric. S'ha suggerit que H. pylori pot ser adquirit per diferents vies de transmissió, entre elles l'aigua. L'aprofitament de les aigües residuals depurades i la resistència d'H. pylori als tractaments de desinfecció de l'aigua constitueix un risc per a la salut.De la mateixa manera, H. pylori presenta capacitat de resistència a tractaments de potabilització i a concentracions elevades de clor lliure en els sistemes de distribució gràcies a la formació de biopel¿lícules. L'estat VNC de H. pylori, en ambdues matrius, fa necessari l'aplicació de tècniques moleculars per a la seva detecció i identificació. En aquesta tesi doctoral s'ha estudiat la presència i viabilitat d'aquest important patogen tant en aigua residual com potable. Un total de 60 mostres d'aigua residual, incloent mostres de l'entrada del reactor biològic, de la sortida d'aquest i després del tractament de desinfecció amb UV, es van analitzar per detectar la presència de H. pylori mitjançant les tècniques moleculars PCR, q-PCR i FISH i cultiu en placa. La tècnica FISH va resultar ser un mètode eficaç i ràpid per a la detecció de H. pylori en les aigües residuals i depurades (61.2 %), sense la necessitat d'un pas previ d'enriquiment de les mostres. Les tècniques PCR i q-PCR van determinar la presència de H. pylori en les mostres, amb percentatges de detecció de les dues del 15 %. Va ser possible quantificar únicament en 3 mostres directes, pertanyents a l'entrada i sortida del reactor (1.8x10; 1.5x10 i 6.3x10 GU/mL). Tot i que el cultiu va resultar ser un mètode poc resolutiu, el mètode d'aïllament mitjançant membrana de 0.65 µm, posat a punt en aquesta tesi doctoral, va resultar eficaç per reduir la microbiota acompanyant i poder obtenir H. pylori cultivable per primera vega

Bacteria of the Arcobacter genus are microorganisms belonging to the Campylobacteraceae family. Currently, the Arcobacter genus comprises 23 species, isolated from a variety of hosts and ecological niches. Although most of the pathogenic species are from fecal origin, seawater is considered to be the habitat for most of them. The transmission to humans seems to be associated to the consumption of raw food or not entirely-cooked. In this regard, the presence of pathogenic Arcobacter species in food of marine origin and vegetables has not been deeply studied. When the detection and identification of Arcobacter is performed exclusively using conventional culture-based methods, the process is slow, tedious and rarely effective many times, originating frequently false negatives. Molecular biology-based methods analyzing nucleic acids with the use of the Polymerase Chain Reaction (PCR), are alternative procedure characterized by being reliable, faster, more sensitive. In this thesis we have analysed the presence of Arcobacter spp in 100 samples from shellfish and another 100 samples from vegetables using both approaches, on one side through the isolation and characterization by plate culture in and on the other side by PCR. The results obtained by both methods confirm the presence of Arcobacter spp. in the samples. An enrichment period followed by PCR has proved to be more sensitive than culture for the detection of the microorganism in the samples. In this study, Arcobacter contamination has been detected in 71 % of the shellfish samples and 20 % of vegetable samples. The obtained Arcobacter isolates have been identified to the species level analyzing the 16 rRNA gene by PCR-RFLP. This technique has allowed the identification of the species A. butzleri, A. cryaerophilus and A. defluvii in the shellfish isolates, being the first time that A. defluvii is identified in clams. Additionally, it is also the first time that Arcobacter spp. is detected in cockles. A. butzleri an, Las bacterias del género Arcobacter son microorganismos pertenecientes a la familia Campylobacteraceae. Actualmente, el género Arcobacter comprende 23 especies, aisladas de una gran diversidad de hospedadores y nichos ecológicos. Las aguas de mar son consideradas el hábitat natural para muchas de ellas, aunque la mayor parte de las especies patógenas son de origen fecal. La transmisión al hombre parece estar asociada al consumo de alimentos crudos o poco cocidos. Sin embargo, la presencia de especies patógenas de Arcobacter en alimentos de origen marino y vegetales ha sido muy poco estudiada. Cuando la detección e identificación de Arcobacter, se establece exclusivamente en función de métodos convencionales de cultivo, el proceso resulta lento, tedioso y poco efectivo en muchas ocasiones, originando frecuentes falsos negativos. Los métodos de detección molecular basados en el análisis de ácidos nucleicos, como la Reacción en Cadena de la Polimerasa (PCR), pueden suponer una alternativa más rápida, sensible y fiable. Por todo ello, en este trabajo se ha realizado la detección de Arcobacter spp. mediante aislamiento por cultivo en placa y PCR, a partir de 100 muestras de moluscos y 100 de verduras. Los resultados obtenidos por ambos métodos confirman la existencia de Arcobacter en las muestras. La PCR, realizada tras un periodo de enriquecimiento, ha resultado ser más sensible que el cultivo para la detección del microorganismo en las muestras. En este trabajo se ha detectado contaminación por Arcobacter en el 71 % de las muestras de moluscos y el 20 % de las muestras de verduras. Los aislados de Arcobacter obtenidos han sido identificados a nivel de especie mediante un análisis PCR-RFLP del gen 16 ARNr. Esta técnica ha permitido identificar las especies A. butzleri, A. cryaerophilus y A. defluvii de los aislados de moluscos, siendo la primera vez que es identificada A. defluvii de muestras de almejas. También es la primera vez que se detecta Arcobacter spp. en berber, Els bacteris del gènere Arcobacter són microorganismes pertanyents a la família Campylobacteraceae. Actualment, el gènere Arcobacter comprèn 23 espècies, aïllades d'una gran diversitat d'hostes i nínxols ecològics. Les aigües de la mar són considerades l'hàbitat natural per a moltes d'aquestes espècies, encara que la major part de les patògenes són d'origen fecal. La transmissió a l'home sembla estar associada al consum d'aliments crus o poc cuits. No obstant això, la presència d'espècies patògenes d'Arcobacter en aliments d'origen marí i vegetals ha sigut molt poc estudiada. Quan la detecció i identificació d'Arcobacter s'estableix exclusivament en funció de mètodes convencionals de cultiu, el procés resulta lent, tediós i sovint poc efectiu, i origina amb freqüència falsos negatius. Els mètodes de detecció molecular basats en l'anàlisi d'àcids nucleics, com la reacció en cadena de la polimerasa (PCR), poden suposar una alternativa més ràpida, sensible i fiable. Per tot això, en aquest treball s'ha realitzat la detecció d'Arcobacter spp. mitjançant aïllament per cultiu en placa i PCR, a partir de 100 mostres de mol·luscos i 100 de verdures. Els resultats obtinguts pels dos mètodes confirmen l'existència d'Arcobacter en les mostres. La PCR, després d'un període d'enriquiment, ha resultat ser més sensible que el cultiu per a la detecció del microorganisme en mostres de mol·luscos. En aquest treball, s'ha detectat contaminació per Arcobacter en el 71 % de les mostres de mol·luscos i el 20 % de les mostres de verdures. Els aïllats d'Arcobacter obtinguts han sigut identificats a nivell d'espècie mitjançant una anàlisi PCR-RFLP del gen 16 ARNr. Aquesta tècnica ha permès identificar les espècies A. butzleri, A. cryaerophilus i A. defluvii en els aïllats de mol·luscos. Aquesta és la primera vegada que A. defluvii és identificada en mostres de cloïsses. També és la primera vegada que es detecta Arcobacter spp. en catxels. En el cas de les verdures, s'han aïllat A. butzleri

OBJECTIVE: Despite a growing interest toward the interplay between H. pylori and gastric microbiota, few data are available about this correlation. The aim of this study was to explore the relationship between H. pylori infection and gas production during lactulose breath test. MATERIALS AND METHODS: Data of patients undergoing both 13C-urea breath test (UBT) and lactulose breath test (LBT) under standard conditions in our GI unit were retrospectively analyzed. GI symptoms, such as dyspepsia, bloating, abdominal pain/discomfort, and epigastric pain on an eleven-point scale were also analyzed and correlate with the results of those tests. H2 and CH4 were calculated using the trapezoidal rule; a considerable CH4 production was defined by AUCCH4 ≥1200 ppm*4h. Statistical analyses were performed with Fisher's exact test and independent samples Mann-Whitney test. RESULTS: Data of 136 patients during a period of time of 3 months were analyzed. 36 patients (26.5%) showed a positive UBT. We do not find any difference as regards age, sex, symptom complaints, and small intestinal bacterial overgrowth between HP negative and positive patients. A greater methane production was observed in infected rather than non-infected patients (47.2% vs. 26% respectively, p=0.02). Furthermore, 25% infected and 10% non-infected produced greater amounts of CH4 compared to H2, resulting in a AUCCH4/AUCH2 ratio >1 (p=0.046). CONCLUSIONS: This study shows for the first time, a significant association between H. pylori infection and methane production, suggesting that H. pylori might influence gut microbiota composition. Further studies are needed to clarify mechanisms underlying this phenomenon

Species of the Epsilonproteobacteria genera Campylobacter, Arcobacter, and Helicobacter are frequently isolated from endothermic mammals and birds. However, little information was available about the presence of Epsilonproteobacteria in ectothermic reptiles and no comprehensive studies had been performed in reptiles. Due to their distinct physiology, reptiles might display a unique microbiome which can provide insights in bacterial host association, adaptation, and speciation. In this thesis, Campylobacter, Arcobacter, and Helicobacter were detected by PCR in 69.3% of the reptiles; 82.5% of the chelonians, 63.8% of the lizards, and 58.0% of the snakes were positive for one or more of these genera. Epsilonproteobacteria were cultured from 22.1% of the reptiles; most frequently from chelonians (37.0%), followed by lizards (19.6%) and snakes (3.0%). The most commonly isolated taxa were Arcobacter butzleri, Arcobacter skirrowii, and two novel reptile-associated Campylobacter taxa; Campylobacter fetus subsp. testudinum and Campylobacter iguaniorum, which are officially described in this thesis. While pathogenicity of both Campylobacter taxa in reptiles is not entirely clear, the presence in many different reptilian hosts and the lack of a clear association with disease seem to preclude a role as primary pathogen. However, Campylobacter fetus subsp. testudinum can cause infections in humans, often with a systemic component. The epidemiological information for nine human cases was summarized. All cases were in men, most of whom were of Asian origin and which were >60 years of age or had immunocompromising conditions. Infection was most likely related to exposure to Asian foods or reptiles. Campylobacter fetus comprises three recognized subspecies, which display distinct host association. Both C. fetus subspecies fetus and venerealis are associated with endothermic mammals, whereas C. fetus subsp. testudinum is primarily associated with ectothermic reptiles. To study thi

Lymphoid tissue inducer (LTi) cells are activated by accessory cell IL-23, and promote lymphoid tissue genesis and antibacterial peptide production by the mucosal epithelium. We investigated the role of LTi cells in the gastric mucosa in the context of microbial infection. Mice deficient in IRAK-M, a negative regulator of TLR signaling, were investigated for increased LTi cell activity, and antibody mediated LTi cell depletion was used to analyze LTi cell dependent antimicrobial activity. H. pylori infected IRAK-M deficient mice developed increased gastric IL-17 and lymphoid follicles compared to wild type mice. LTi cells were present in naive and infected mice, with increased numbers in IRAK-M deficient mice by two weeks. Helicobacter and Candida infection of LTi cell depleted rag1(-/-) mice demonstrated LTi-dependent increases in calprotectin but not RegIII proteins. However, pathogen and commensal microbiota populations remained unchanged in the presence or absence of LTi cell function. These data demonstrate LTi cells are present in the stomach and promote lymphoid follicle formation in response to infection, but are limited by IRAK-M expression. Additionally, LTi cell mediated antimicrobial peptide production at the gastric epithelium is less efficacious at protecting against microbial pathogens than has been reported for other tissues.

Standard endoscopy has improved assessment of gastrointestinal disease in a relatively non-invasive manner. However gross endoscopic examination of the mucosa does not always correlate with histopathology. This has led to development of advanced endoscopic techniques allowing real-time histopathologically-equivalent examination that potentially circumvents the need for biopsy altogether. Confocal endomicroscopy (CEM) has not been established in dogs, but applications in gastroenterology may prove useful. Before abnormalities can be appropriately interpreted, protocols for implementation need to be investigated together with assessment and description of normal mucosal topologic morphology. One described application of CEM is in the identification of Helicobacter pylori and assessment of the severity of associated gastritis in people. Additionally, CEM aids identification of other mucosally associated and intracellular bacteria. In dogs, the role of non-Helicobacter pylori Helicobacters (NHPH) remains undetermined. Despite high infection prevalences, studies fail to demonstrate a significant impact on gastric function, nor a relationship with gastritis or neoplasia. The pathogenic potential of individual NHPH may differ, however discriminating between these can be challenging. Pathogenic potential could reflect differences in adherence or virulence factors between species, therefore distinguishing individual NHPH could be important. Pathogenicity may also relate to capability for invasion of the intracellular space, and this is frequently recognised in dogs. This thesis established the potential usefulness of CEM in dogs, through studies that evaluated the pharmacokinetics of intravenous fluorescein, and that assessed the topographic morphology of the small intestinal and gastric mucosa in clinically healthy dogs. This allowed establishment of fluorophore protocols, and an understanding of normal morphology. In addition change correlating with lymphocytic gastritis w

Lymphoid tissue inducer (LTi) cells are activated by accessory cell IL-23, and promote lymphoid tissue genesis and antibacterial peptide production by the mucosal epithelium. We investigated the role of LTi cells in the gastric mucosa in the context of microbial infection. Mice deficient in IRAK-M, a negative regulator of TLR signaling, were investigated for increased LTi cell activity, and antibody mediated LTi cell depletion was used to analyze LTi cell dependent antimicrobial activity. H. pylori infected IRAK-M deficient mice developed increased gastric IL-17 and lymphoid follicles compared to wild type mice. LTi cells were present in naive and infected mice, with increased numbers in IRAK-M deficient mice by two weeks. Helicobacter and Candida infection of LTi cell depleted rag1(-/-) mice demonstrated LTi-dependent increases in calprotectin but not RegIII proteins. However, pathogen and commensal microbiota populations remained unchanged in the presence or absence of LTi cell function. These data demonstrate LTi cells are present in the stomach and promote lymphoid follicle formation in response to infection, but are limited by IRAK-M expression. Additionally, LTi cell mediated antimicrobial peptide production at the gastric epithelium is less efficacious at protecting against microbial pathogens than has been reported for other tissues.

Helicobacter pylori infection is one of the most common human infections in the world. The bacteria cause peptic ulcer disease and their infection is an important factor for gastric cancer development. The bacteria are transmitted from person to person within families, with young children most often infected. The bacteria reside in the stomach for a lifetime if untreated by antimicrobial agents. Many virulence factors are known that contribute to the persistence of the bacteria in the stomach, and the bacteria harbors a pathogenicity island in its genome. The discovery of H. pylori as a cause of gastritis in the stomach led to the Nobel Prize in Physiology or Medicine 2005.

Helicobacter pylori infects more than half of the world's population, and is known to be involved in several diseases including gastric cancer. Its close interactions with the stomach and host immune system serves as a good model to study the co-adaptation and co-evolution of the organisms in the stomach micro-environment. In this project, we utilized RNA-seq and data analysis tools to investigate differentially expressed genes by H. pylori in patients at different stages of early gastric cancer development. We also investigated the abundance and diversity of bacterial genera other than H. pylori, and looked for correlations with H. pylori presence and number. For differential gene expression of H. pylori, one gene was differentially expressed between samples of corpus atrophy without metaplasia vs. samples of antrum gastritis, and eight genes were found to be differentially expressed between samples of corpus atrophy with metaplasia vs. samples with pan-gastritis. When samples were clustered into different groups based on the expression data, 52 genes (shared or unique to the specific comparison groups) were found to be differentially expressed, but no apparent patterns were observed that could be explained by medical or sample collection data. For bacterial diversity and abundances, we found several genera colonizing the stomach, of which some have been previously identified. While most of these bacteria colonize regardless of the presence of H. pylori, the abundance of three genera, Wolinella, Campylobacter, and Veillonella, seem to be correlated with the presence of H. pylori.

Helicobacter pylori infects more than half of the world's population, and is known to be involved in several diseases including gastric cancer. Its close interactions with the stomach and host immune system serves as a good model to study the co-adaptation and co-evolution of the organisms in the stomach micro-environment. In this project, we utilized RNA-seq and data analysis tools to investigate differentially expressed genes by H. pylori in patients at different stages of early gastric cancer development. We also investigated the abundance and diversity of bacterial genera other than H. pylori, and looked for correlations with H. pylori presence and number. For differential gene expression of H. pylori, one gene was differentially expressed between samples of corpus atrophy without metaplasia vs. samples of antrum gastritis, and eight genes were found to be differentially expressed between samples of corpus atrophy with metaplasia vs. samples with pan-gastritis. When samples were clustered into different groups based on the expression data, 52 genes (shared or unique to the specific comparison groups) were found to be differentially expressed, but no apparent patterns were observed that could be explained by medical or sample collection data. For bacterial diversity and abundances, we found several genera colonizing the stomach, of which some have been previously identified. While most of these bacteria colonize regardless of the presence of H. pylori, the abundance of three genera, Wolinella, Campylobacter, and Veillonella, seem to be correlated with the presence of H. pylori.

The discovery of Helicobacter pylori infection in the stomach could be considered as one of the most important events of modern gastroenterology. Understanding of the natural history of many disorders of the upper gastrointestinal tract, including chronic gastritis, peptic ulcer disease, gastric cancer and MALT lymphoma, was altered by this discovery. Interestingly, epidemiological studies have also revealed a correlation between H. pylori infection and some diseases localized outside the stomach, especially those characterized by persistent and low-grade systemic inflammation. Of note, H. pylori has an important role in iron deficiency anaemia, idiopathic thrombocytopenic purpura and vitamin B12 deficiency. Moreover, the association of this bacterial pathogen with many other diseases, including hepatobiliary, pancreatic, cardiovascular and neurodegenerative disorders is currently under investigation. In this Review, we summarize the results of the most important studies performed to date surrounding the association of H. pylori infection with extragastric diseases, as well as the strength of the evidence. We also provide information concerning bacterial-host interactions and the mechanisms implicated in the pathogenesis of each of these extragastric diseases.

Helicobacter pylori virulent strains have been shown to affect cardiovascular diseases through molecular mimicry mechanisms. Silent autoimmune myocarditis has been hypothesized to be the cause of idiopathic dysrhythmias (IA). The aim of this study is to assess the prevalence of virulent H. pylori strains in patients affected by IA. In this study,54 patients (40 men, mean age 44 ± 17 years) affected by IA and 50 healthy subjects (34 men, mean age 45 ± 9) were evaluated. IA, defined as dysrhythmias with no evidence of other cardiac pathology, were either supraventricular (SVA, 23 patients; mean age 45 ± 15 years) or ventricular (VA, 31 patients; mean age 42 ± 18 years). H. pylori infection and gastrointestinal (GI) symptoms were evaluated. H. pylori strains expressing the cytotoxin-associated gene A (cagA) and the vacuolating-cytotoxin A (vacA) were also assessed through western blot. The prevalence of H. pylori is similar in IA patients and in controls (42 vs. 44%; p > 0.05); H. pylori infection is observed in 48 and 39% of the patients are affected by SVA and VA, respectively. The prevalence of CagA-positive strains is increased in IA patients compared to controls (65 vs. 42%; p < 0.01); similarly, the prevalence of VacA-positive strains is also increased in IA patients (74 vs. 46%; p < 0.006). Excluding belching, infected patients did not show any difference in GI symptoms, when compared to non-infected subjects. From this study it is concluded that there is an epidemiological link between CagA and VacA-positive H. pylori strains in IA patients.

Background: Bacteria belonging to the Arcobacter genus are emerging enteropathogens and potential zoonotic agents. Their taxonomy has evolved very rapidly, and there are presently 18 recorded species. The prevalence of species belonging to Arcobacter is underestimated because of the limitations of currently available methods for species identification. The aim of this study was to compare the performance of five PCR based methods that target regions of 16S rRNA, 23S rRNA or gyrA genes to identify Arcobacter species, and to review previous results reported in the literature using these methods. Results: The five tested methods were found not to be reliable. They misidentified between 16.8% and 67.4% of the studied strains; this was dependent upon the target regions of the tested genes. The worst results obtained were for the identification of Arcobacter cryaerophilus and Arcobacter butzleri when the 23S rRNA gene was used as the target. These species were confused with many non-targeted species. Conclusion: Our results suggest that the known diversity of Arcobacter spp. in different environments could be expanded if reliable identification methods are applied in future studies.

Assessment of a single serum sample for Helicobacter pylori antibodies is frequently requested in routine diagnostic laboratories. Current enzyme linked immunosorbent assay (ELISA) kits are not ideal for testing small numbers of serum samples and some have low sensitivities, specificities or large grey zones.-A panel of 90 serum samples from patients who had presented for routine upper endoscopy was used to compare three kits for the detection of H pylori antibodies: (1) Pyloriset Dry, total antibody latex agglutination, Orion Diagnostica, Espoo, Finland; (2) Pyloriset enzyme immunoassay (EIA), IgG ELISA, Orion; and (3) Hel-p, IgG ELISA, Amrad, Kew, Victoria, Australia. Diagnosis of H pylori positivity was made if culture results and either rapid urease test or histopathology were positive. The sensitivity, specificity, positive, and negative predictive value for each test was as follows: Orion: latex 93.3%, 95.6%, 95.5%, 93.3%, respectively; Orion: EIA-G 84.4%, 97.8%, 97.4%, 84.4%, respectively; and Amrad: EIA-G 100%, 88.9%, 90%, 100%, respectively. The latex test performed better than the EIAs with respect to sensitivity and specificity.

Assessment of a single serum sample for Helicobacter pylori antibodies is frequently requested in routine diagnostic laboratories. Current enzyme linked immunosorbent assay (ELISA) kits are not ideal for testing small numbers of serum samples and some have low sensitivities, specificities or large grey zones.-A panel of 90 serum samples from patients who had presented for routine upper endoscopy was used to compare three kits for the detection of H pylori antibodies: (1) Pyloriset Dry, total antibody latex agglutination, Orion Diagnostica, Espoo, Finland; (2) Pyloriset enzyme immunoassay (EIA), IgG ELISA, Orion; and (3) Hel-p, IgG ELISA, Amrad, Kew, Victoria, Australia. Diagnosis of H pylori positivity was made if culture results and either rapid urease test or histopathology were positive. The sensitivity, specificity, positive, and negative predictive value for each test was as follows: Orion: latex 93.3%, 95.6%, 95.5%, 93.3%, respectively; Orion: EIA-G 84.4%, 97.8%, 97.4%, 84.4%, respectively; and Amrad: EIA-G 100%, 88.9%, 90%, 100%, respectively. The latex test performed better than the EIAs with respect to sensitivity and specificity.

Helicobacter pylori is a significant gastric pathogen in humans, with gastritis and gastric neoplasia frequently resulting from chronic colonisation. The organism is reliant on its antioxidant enzyme system for survival, and this thesis proposes that components of this system – namely, the antioxidant enzymes superoxide dismutase (HpSOD), catalase (HpKatA), and thiolperoxidase (HpTpx) - present a viable therapeutic target in H. pylori infection. Using a pET Escherichia coli expression system, recombinant forms of the three enzymes from H. pylori were created and then trialled as vaccine antigens administered with an appropriate adjuvant via systemic and mucosal routes. Moreover, in order to assess for synergistic action, the enzymes were assessed both individually and in combination. These trials demonstrated that superoxide dismutase and thiolperoxidase are protective antigens, but no additional protection was observed with the combination vaccine. The essential requirement for the antioxidant system in H. pylori further led to speculation that inhibition of enzyme function may be an alternative mode of therapy. Monoclonal antibodies directed against the three enzymes were generated via hybridomas derived from hyperimmunised mice. Antibodies were characterised by class and isotype, binding properties and ability to inhibit enzyme function, in order to determine the most promising candidates for therapeutic trials. After demonstrating the presence of systemic antibodies at the gastrointestinal mucosal surface in a mouse trial, the candidate antibodies were administered via intraperitoneal injection to mice infected with H. pylori. Although the antibody therapy did not impair colonisation, there was a significant increase in a number of pro-inflammatory cytokines within gastric tissue following administration of the anti-HpSOD antibody. Investigating further, it was found that incubation of macrophages in the presence of recombinant HpSOD attenuated the cytokine resp

Background: Arcobacter spp. (family Campylobacteraceae) are ubiquitous zoonotic bacteria that are being increasingly recognised as a threat to human health. A previously published 16S rRNA-RFLP Arcobacter spp. identification method produced specific RFLP patterns for the six species described at that time, using a single endonuclease (MseI). The number of characterised Arcobacter species has since risen to 17. The aim of the present study was to update the 16S rRNA-RFLP identification method to include all currently characterised species of Arcobacter. Results: Digestion of the 16S rRNA gene with the endonuclease MseI produced clear, distinctive patterns for 10 of the 17 species, while the remaining species shared a common or very similar RFLP pattern. Subsequent digestion of the 16S rRNA gene from these species with the endonucleases MnlI and/or BfaI generated species-specific RFLP patterns. Conclusions: 16S rRNA-RFLP analysis identified 17 Arcobacter spp. using either polyacrylamide or agarose gel electrophoresis. Microheterogeneities within the 16S rRNA gene, which interfered with the RFLP identification, were also documented for the first time in this genus, particularly in strains of Arcobacter cryaerophilus isolated from animal faeces and aborted foetuses.

Among the currently described eubacterial phyla, the Proteobacteria represent the largest and one of the most diverse groups of organisms (237). This phylum consists of over 200 genera and contains the majority of Gram-negative species (237). The group consists of five subdivisions: Alpha-, Beta-,Gamma-, Delta-, and Epsilonproteobacteria. Although the subdivisions evolved from a common ancestor, the estimated divergence dates indicate that individual proteobacterial subdivisions branched separately and in a particular order, with the delta subdivision having branched first, approximately 2.38 billion years ago, followed by the epsilon, alpha, beta, and gamma subdivisions (237, 536)., Published in Microbiology and Molecular Biology Reviews, v75 n1 p84-132, March 2011.

Cellular inhibitor of apoptosis protein 2 (cIAP2) is a member of the IAP family and is over-expressed in most cancer tissues. In this study, we investigated the role cIAP2 in Helicobacter pylori (HP) related gastric carcinogenesis. We measured the expression of cIAP2 at mRNA and protein levels in a panel of gastric cancer cell lines and human gastric cancer tissues by semi-quantitative reverse transcriptase PCR (RT-PCR), quantitative real time PCR (qPCR), immunoblotting, and immunohistochemistry. The effects of cIAP2 down-regulation on gastric cell proliferation and apoptosis were detected by standard WST-1 assay and flow cytometry, respectively. Infection of gastric mucosa by HP enhances the expression of cIAP2 in mouse gastric tissues. Over 70% of human gastric cancer tissues express higher amount of cIAP2. Well-differentiated gastric cancer cells express more cIAP2 than moderately- and poorly-differentiated gastric cancer cells. Knocking down of cIAP2 in SGC-7901 cells results in a 30% decrease in cell proliferation, a 20% increase in apoptosis and delayed migration. Thus, cIAP2 may play an important role in HP-induced gastric carcinogenesis, and it may serve as a potential target for gastric cancer therapy.

Cellular inhibitor of apoptosis protein 2 (cIAP2) is a member of the IAP family and is over-expressed in most cancer tissues. In this study, we investigated the role cIAP2 in Helicobacter pylori (HP) related gastric carcinogenesis. We measured the expression of cIAP2 at mRNA and protein levels in a panel of gastric cancer cell lines and human gastric cancer tissues by semi-quantitative reverse transcriptase PCR (RT-PCR), quantitative real time PCR (qPCR), immunoblotting, and immunohistochemistry. The effects of cIAP2 down-regulation on gastric cell proliferation and apoptosis were detected by standard WST-1 assay and flow cytometry, respectively. Infection of gastric mucosa by HP enhances the expression of cIAP2 in mouse gastric tissues. Over 70% of human gastric cancer tissues express higher amount of cIAP2. Well-differentiated gastric cancer cells express more cIAP2 than moderately- and poorly-differentiated gastric cancer cells. Knocking down of cIAP2 in SGC-7901 cells results in a 30% decrease in cell proliferation, a 20% increase in apoptosis and delayed migration. Thus, cIAP2 may play an important role in HP-induced gastric carcinogenesis, and it may serve as a potential target for gastric cancer therapy.

Cellular inhibitor of apoptosis protein 2 (cIAP2) is a member of the IAP family and is over-expressed in most cancer tissues. In this study, we investigated the role cIAP2 in Helicobacter pylori (HP) related gastric carcinogenesis. We measured the expression of cIAP2 at mRNA and protein levels in a panel of gastric cancer cell lines and human gastric cancer tissues by semi-quantitative reverse transcriptase PCR (RT-PCR), quantitative real time PCR (qPCR), immunoblotting, and immunohistochemistry. The effects of cIAP2 down-regulation on gastric cell proliferation and apoptosis were detected by standard WST-1 assay and flow cytometry, respectively. Infection of gastric mucosa by HP enhances the expression of cIAP2 in mouse gastric tissues. Over 70% of human gastric cancer tissues express higher amount of cIAP2. Well-differentiated gastric cancer cells express more cIAP2 than moderately- and poorly-differentiated gastric cancer cells. Knocking down of cIAP2 in SGC-7901 cells results in a 30% decrease in cell proliferation, a 20% increase in apoptosis and delayed migration. Thus, cIAP2 may play an important role in HP-induced gastric carcinogenesis, and it may serve as a potential target for gastric cancer therapy.