DSpace Collection:
http://hdl.handle.net/10261/362
2024-03-29T12:01:26ZNitrate reduction capacity of the oral microbiota is impaired in periodontitis: potential implications for systemic nitric oxide availability
http://hdl.handle.net/10261/350046
Título: Nitrate reduction capacity of the oral microbiota is impaired in periodontitis: potential implications for systemic nitric oxide availability
Autor: Rosier, Bob T.; Johnston, William; Carda-Dieguez, Miguel; Simpson, Annabel; Cabello-Yeves, Elena; Piela, Krystyna; Reilly, Robert; Artacho, Alejandro; Easton, Chris; Burleigh, Mia; Culshaw, Shauna; Mira, Alex
Resumen: The reduction of nitrate to nitrite by the oral microbiota has been proposed to be important for oral health and results in nitric oxide formation that can improve cardiometabolic conditions. Studies of bacterial composition in subgingival plaque suggest that nitrate-reducing bacteria are associated with periodontal health, but the impact of periodontitis on nitrate-reducing capacity (NRC) and, therefore, nitric oxide availability has not been evaluated. The current study aimed to evaluate how periodontitis affects the NRC of the oral microbiota. First, 16S rRNA sequencing data from five different countries were analyzed, revealing that nitrate-reducing bacteria were significantly lower in subgingival plaque of periodontitis patients compared with healthy individuals (P < 0.05 in all five datasets with n = 20-82 samples per dataset). Secondly, subgingival plaque, saliva, and plasma samples were obtained from 42 periodontitis patients before and after periodontal treatment. The oral NRC was determined in vitro by incubating saliva with 8 mmol/L nitrate (a concentration found in saliva after nitrate-rich vegetable intake) and compared with the NRC of 15 healthy individuals. Salivary NRC was found to be diminished in periodontal patients before treatment (P < 0.05) but recovered to healthy levels 90 days post-treatment. Additionally, the subgingival levels of nitrate-reducing bacteria increased after treatment and correlated negatively with periodontitis-associated bacteria (P < 0.01). No significant effect of periodontal treatment on the baseline saliva and plasma nitrate and nitrite levels was found, indicating that differences in the NRC may only be revealed after nitrate intake. Our results suggest that an impaired NRC in periodontitis could limit dietary nitrate-derived nitric oxide levels, and the effect on systemic health should be explored in future studies.
Descripción: 10 páginas, 5 figuras2024-03-12T08:53:31ZA second update on mapping the human genetic architecture of COVID-19
http://hdl.handle.net/10261/349735
Título: A second update on mapping the human genetic architecture of COVID-19
Autor: Masahiro Kanai; Martin, Javier; Acosta-Herrera, Marialbert; Pérez-Tur, Jordi; Matthew Solomonson
Resumen: Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article.2024-03-08T09:40:05ZDispersal history of SARS-CoV-2 in Galicia, Spain
http://hdl.handle.net/10261/348967
Título: Dispersal history of SARS-CoV-2 in Galicia, Spain
Autor: Gallego-García, Pilar; Estévez-Gómez, Nuria; De Chiara, Loretta; Alvariño, Pilar; Juiz-González, Pedro M.; Torres-Beceiro, Isabel; Poza, Margarita; Vallejo, Juan A.; Rumbo-Feal, Soraya; Conde-Pérez, Kelly; Aja-Macaya, Pablo; Ladra, Susana; Moreno-Flores, Antonio; Gude-González, María J.; Coira, Amparo; Aguilera, Antonio; Costa-Alcalde, José J.; Trastoy, Rocío; Barbeito-Castiñeiras, Gema; García-Souto, Daniel; Tubio, José M. C.; Trigo-Daporta, Matilde; Camacho-Zamora, Pablo; García Costa, Juan; González-Domínguez, María; Luis Canoura-Fernández,; Glez-Peña, Daniel; Pérez-Castro, Sonia; Cabrera, Jorge J.; Daviña-Núñez, Carlos; Godoy-Diz, Montserrat; Treinta-Álvarez, Ana Belén; Veiga, Maria Isabel; Sousa, João Carlos; Osório, Nuno S.; Comas, Iñaki; González-Candelas, Fernando; Hong, Samuel L.; Bollen, Nena; Dellicour, Simon; Baele, Guy; Suchard, Marc A.; Lemey, Philippe; Andrés Agulla,; Bou, Germán; Alonso-García, Pilar; Pérez-del-Molino, María Luisa; García-Campello, Marta; Paz-Vidal, Isabel; Regueiro, Benito; Posada, David
Resumen: The dynamics of SARS-CoV-2 transmission are influenced by a variety of factors, including social restrictions and the emergence of distinct variants. In this study, we delve into the origins and dissemination of the Alpha, Delta, and Omicron variants of concern in Galicia, northwest Spain. For this, we leveraged genomic data collected by the EPICOVIGAL Consortium and from the GISAID database, along with mobility information from other Spanish regions and foreign countries. Our analysis indicates that initial introductions during the Alpha phase were predominantly from other Spanish regions and France. However, as the pandemic progressed, introductions from Portugal and the USA became increasingly significant. Notably, Galicia’s major coastal cities emerged as critical hubs for viral transmission, highlighting their role in sustaining and spreading the virus. This research emphasizes the critical role of regional connectivity in the spread of SARS-CoV-2 and offers essential insights for enhancing public health strategies and surveillance measures.2024-03-01T12:04:47ZThe Helicobacter pylori Genome Project: insights into H. pylori population structure from analysis of a worldwide collection of complete genomes
http://hdl.handle.net/10261/347116
Título: The Helicobacter pylori Genome Project: insights into H. pylori population structure from analysis of a worldwide collection of complete genomes
Autor: Thorell, Kaisa; Munoz-Ramirez, Zilia Y.; Wang, Difei; Sandoval-Motta, Santiago; Boscolo Agostini, Rajiv; Ghirotto, Silvia; Torres, Roberto C.; Comas, Iñaki; Falush, Daniel; Camargo, M. Constanza; Rabkin, Charles S.; HpGP Research Network
Resumen: Helicobacter pylori, a dominant member of the gastric microbiota, shares co-evolutionary history with humans. This has led to the development of genetically distinct H. pylori subpopulations associated with the geographic origin of the host and with differential gastric disease risk. Here, we provide insights into H. pylori population structure as a part of the Helicobacter pylori Genome Project (HpGP), a multi-disciplinary initiative aimed at elucidating H. pylori pathogenesis and identifying new therapeutic targets. We collected 1011 well-characterized clinical strains from 50 countries and generated high-quality genome sequences. We analysed core genome diversity and population structure of the HpGP dataset and 255 worldwide reference genomes to outline the ancestral contribution to Eurasian, African, and American populations. We found evidence of substantial contribution of population hpNorthAsia and subpopulation hspUral in Northern European H. pylori. The genomes of H. pylori isolated from northern and southern Indigenous Americans differed in that bacteria isolated in northern Indigenous communities were more similar to North Asian H. pylori while the southern had higher relatedness to hpEastAsia. Notably, we also found a highly clonal yet geographically dispersed North American subpopulation, which is negative for the cag pathogenicity island, and present in 7% of sequenced US genomes. We expect the HpGP dataset and the corresponding strains to become a major asset for H. pylori genomics.
Descripción: 16 páginas, 5 figuras, 1 tabla. Acompaña lista de autores del HpGP Research Network. La versión online contiene material suplementario.2024-02-14T14:02:37Z