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Deep-amplicon sequencing (DAS) analysis to determine the presence of pathogenic Helicobacter species in wastewater reused for irrigation
2020
Hortelano, Irene | Moreno Koch, Yolanda | Moreno-Mesonero, Laura | Ferrús, María Antonia
Wastewater has become one of the most important and least expensive water for the agriculture sector, as well as an alternative to the overexploitation of water resources. However, inappropriate treatment before its reuse can result in a negative impact on the environment, such as the presence of pathogens. This poses an increased risk for environmental safety, which can subsequently lead to an increased risk for human health. Among all the emerging wastewater pathogens, bacteria of the genus Helicobacter are some of the most disturbing ones, since they are directly related to gastric illness and hepatobiliary and gastric cancer. Therefore, the aim of this study was to determine the presence of potentially pathogenic Helicobacter spp. in treated wastewater intended for irrigation. We used a next generation sequencing approach, based on Illumina sequencing in combination with culture and other molecular techniques (qPCR, FISH and DVC-FISH), to analyze 16 wastewater samples, with and without an enrichment step. By culture, one of the direct samples was positive for H. pylori. FISH and DVC-FISH techniques allowed for detecting viable Helicobacter spp., including H. pylori, in seven out of eight samples of wastewater from the tertiary effluents, while qPCR analysis yielded only three positive results. When wastewater microbiome was analyzed, Helicobacter genus was detected in 7 samples. The different molecular techniques used in the present study provided evidence, for the first time, of the presence of species belonging to the genus Helicobacter such as H. pylori, H. hepaticus, H. pullorum and H. suis in wastewater samples, even after disinfection treatment.
Afficher plus [+] Moins [-]Detection of Helicobacter pylori in the coastal waters of Georgia, Puerto Rico and Trinidad
2014
Holman, Chelsea B. | Bachoon, D.S. | Otero, Ernesto | Ramsubhag, Adesh
Fecal pollution in the coastal marine environments was assessed at eleven sampling locations along the Georgia coast and Trinidad, and nine sites from Puerto-Rico. Membrane filtration (EPA method 1604 and method 1600) was utilized for Escherichia coli and enterococci enumeration at each location. Quantitative polymerase chain reaction (qPCR) amplification of the 16S ribosomal RNA gene was used to determine the presence of the Helicobacter pylori in marine samples. There was no significant correlation between the levels of E. coli, enterococci and H. pylori in these water samples. H. pylori was detected at four of the 31 locations sampled; Oak Grove Island and Village Creek Landing in Georgia, Maracas river in Trinidad, and Ceiba Creek in Puerto Rico. The study confirms the potential public health risk to humans due to the widespread distribution of H. pylori in subtropical and tropical costal marine waters.
Afficher plus [+] Moins [-]Genotypic detection of metronidazole and clarithromycin resistance in dyspeptic patients with helicobacter pylori [Erratum: June 2022, v.29(27); p.41475]
2022
Nemr, Nader | Kishk, Rania M. | Salem, Ayman | Abdalla, Mohamed O. | Abd El-Fadeal, Noha M. | Soliman, Nashaat M.
In Egypt, antibiotic sensitivity analysis for Helicobacter pylori is not routinely performed. We aimed to identify the clarithromycin and metronidazole resistance directly from gastric biopsies for better guide treatment regimens. This cross-sectional descriptive study included 75 adult dyspeptic patients referred to the upper endoscopy unit in Suez Canal University Hospital, Ismailia, Egypt. Gastric biopsies were taken for rapid urease test (RUT) and cultured on brucella agar with antibiotic supplements. Genomic DNA was extracted directly from the specimen, and PCR was performed for direct detection of H. pylori. Also, to explore clarithromycin and metronidazole resistance, mutations in the 23S rRNA gene and the rdxA gene were investigated. We found that 60 samples were positive to RUT (80%), and only 4 samples were positive by culture. UreC gene was detected in 45 specimens. Meanwhile, 26 isolates were contained mutations at positions 2142 and 2143. Amplification of the metronidazole rdx gene was performed by conventional PCR. Out of 45 isolates, DNA sequence analysis of PCR product showed the wild type (ACA) in 9 isolates, while the mutant type (ATA) was detected in 28 isolates. We found a significant proportion of clarithromycin and metronidazole resistance among H. pylori infected patients in our region.
Afficher plus [+] Moins [-]Disinfection and removal of human pathogenic bacteria in arctic waste stabilization ponds
2018
Huang, Yannan | Truelstrup Hansen, Lisbeth | Ragush, Colin M. | Jamieson, Rob C.
Wastewater stabilization ponds (WSPs) are commonly used to treat municipal wastewater in Arctic Canada. The biological treatment in the WSPs is strongly influenced by climatic conditions. Currently, there is limited information about the removal of fecal and pathogenic bacteria during the short cool summer treatment season. With relevance to public health, the objectives of this paper were to determine if treatment in arctic WSPs resulted in the disinfection (i.e., removal of fecal indicator bacteria, Escherichia coli) and removal of selected human bacterial pathogens from the treated effluent. The treatment performance, with focus on microbial removal, was assessed for the one-cell WSP in Pond Inlet (Nunavut [NU]) and two-cell WSP in Clyde River (NU) over three consecutive (2012–2014) summer treatment seasons (late June-early September). The WSPs provided a primary disinfection treatment of the wastewater with a 2–3 Log removal of generic indicator E. coli. The bacterial pathogens Salmonella spp., pathogenic E. coli, and Listeria monocytogenes, but not Campylobacter spp. and Helicobacter pylori, were detected in the untreated and treated wastewater, indicating that human pathogens were not reliably removed. Seasonal and annual variations in temperature significantly (p < 0.05) affected the disinfection efficiency. Improved disinfection and pathogen removal was observed for the two-cell system in Clyde River as compared to the one-cell system in Pond Inlet. A quantitative microbial risk assessment should be performed to determine if the release of low levels of human pathogens into the arctic environment poses a human health risk.
Afficher plus [+] Moins [-]What is the possible therapeutic effect of Ginkgo biloba on gastric ulcer induced by ammonia in albino rats?
2020
El-Medany, Azza | Guemei, Aida Ahmed Said | Abdel Twab, Raeesa | Al-Matrafi, Tahani | El-Medany, Jamila
Gastric ulcer is a worldwide disease. Helicobacter pylori is one of the most common chronic bacterial infections that induce chronic inflammation in the gastric mucosa, mediated by an array of pro-and inflammatory cytokines. The aim of this study was to investigate the possible therapeutic effects of Ginkgo biloba extract on gastric ulcer induced by ammonium hydroxide in rats and the potential underlying mechanisms. The study was done on 32 adult male Wistar albino rats, divided equally into 4 groups: normal control, gastric ulcer–induced group using 1 ml of 1% NH₄OH orally, ulcer control group; rats received 1% carboxymethyl cellulose daily for 14 days after induction of ulcer and treated rats received orally 200 mg/kg Ginkgo biloba once daily for 14 days after induction of ulcer. The study revealed administration of ammonia showed multiple gastric lesions; edema, hyperemia, hemorrhage, and ulcers with a significant increase in ulcer score, myeloperoxidase (MPO), and interleukin-1β (IL-1β) and a significant decrease in reduced glutathione (GSH), mucus amount, and gastric pH. After the administration of Ginkgo biloba, there was an improvement in gastric lesions, with a significant reduction of ulcer score, MPO, and IL-1β and a significant increase in GSH, mucus content, and gastric pH. Moreover, collagen types I and IV were gradually increased in the treated group.
Afficher plus [+] Moins [-]Association of tobacco smoke–infused water (tuibur) use by Mizo people and risk of Helicobacter pylori infection
2020
Mukherjee, Subhajit | Madathil, Sreenath Arekurnnath | Ghatak, Souvik | Jahau, Lalrintluanga | Pautu, Jeremy L. | Zohmingthanga, John | Pachuau, Lalawmpuii | Nicolau, Belinda | Kumar, Nachimuthu Senthil
The study aims to understand the influence of environmental and lifestyle factors and more specifically the role of tobacco smoke–infused water (tuibur) on Helicobacter pylori infection. It was a cross-sectional study to measure the epidemiological risk factors associated with H. pylori infection among the tribal population in Northeast India. Endoscopic samples were collected from the antrum region of the stomach from 863 participants with gastritis. H. pylori infection was confirmed in 475 samples by the rapid urease test and PCR-based methods. Information on demographic and lifestyle factors was collected using a validated and standardized questionnaire. Logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (CI) for the association between the various factors and H. pylori. The use of tuibur was associated with an increased OR of H. pylori infection (OR = 3.32, 95% Cl = 1.95–5.83). Tobacco chewers (OR = 1.49, 95% Cl = 1.06–2.09), smokers (OR = 1.81, 95% Cl = 1.26–2.61), and alcohol consumers (OR = 1.81, 95% Cl = 1.19–2.76) were also infected with H. pylori. The results were not attenuated after adjusting for major well-known risk factors of H. pylori infection. The habit of tuibur consumption may be a contributing factor to the high prevalence of H. pylori infection and in turn, may contribute to the high prevalence of gastritis among the Mizo population.
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