Search results for "bacteria."
showing 10 items of 4757 documents
Propolis as a Cariostatic Agent in Lozenges and Impact of Storage Conditions on the Stability of Propolis
2023
Propolis is known as a source of compounds with strong antibacterial activity. Due to the antibacterial effect against streptococci of the oral cavity, it seems to be a useful agent in decreasing the accumulation of dental plaque. It is rich in polyphenols which are responsible for a beneficial impact on the oral microbiota and antibacterial effect. The aim of the study was to evaluate the antibacterial effect of Polish propolis against cariogenic bacteria. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined on cariogenic streptococci related to the occurrence of dental caries. Lozenges based on xylitol, glycerin, gelatin, water, and ethan…
Genome degeneration and adaptation in a nascent stage of symbiosis
2014
Symbiotic associations between animals and microbes are ubiquitous in nature, with an estimated 15% of all insect species harboring intracellular bacterial symbionts. Most bacterial symbionts share many genomic features including small genomes, nucleotide composition bias, high coding density, and a paucity of mobile DNA, consistent with long-term host association. In this study, we focus on the early stages of genome degeneration in a recently derived insect-bacterial mutualistic intracellular association. We present the complete genome sequence and annotation of Sitophilus oryzae primary endosymbiont (SOPE). We also present the finished genome sequence and annotation of strain HS, a close…
Fighting Antibiotic Resistance: New Pyrimidine-Clubbed Benzimidazole Derivatives as Potential DHFR Inhibitors
2023
The present work describes the design and development of seventeen pyrimidine-clubbed benzimidazole derivatives as potential dihydrofolate reductase (DHFR) inhibitors. These compounds were filtered by using ADMET, drug-likeness characteristics calculations, and molecular docking experiments. Compounds 27, 29, 30, 33, 37, 38, and 41 were chosen for the synthesis based on the results of the in silico screening. Each of the synthesized compounds was tested for its in vitro antibacterial and antifungal activities using a variety of strains. All the compounds showed antibacterial properties against Gram-positive bacteria (Staphylococcus aureus and Staphylococcus pyogenes) as well as Gram-negativ…
Activation of NF-kappaB and IL-8 by yersinia enterocolitica invasin protein is conferred by engagement of rac1 and MAP kinase cascades.
2003
International audience; Yersinia enterocolitica triggers activation of the nuclear factor (NF)-kappaB and production of the proinflammatory chemokine interleukin (IL)-8 in intestinal epithelial cells. This activation is due to adhesion of the bacteria via their outer membrane protein invasin to the host cells. Using Clostridium difficile toxins that specifically inactivate small GTPases, and transfection of inhibitory proteins of the Rho-GTPases, we demonstrate that Rac1, but not Cdc42 or Rho, is required for activation of NF-kappaB by invasin. Invasin activated the mitogen activated protein kinases (MAPK) p38 and c-Jun N-terminal protein kinase (JNK) but not extracellular signal regulated …
Questing abundance of adult taiga ticks Ixodes persulcatus and their Borrelia prevalence at the north-western part of their distribution
2020
Background Because ixodid ticks are vectors of zoonotic pathogens, including Borrelia, information of their abundance, seasonal variation in questing behaviour and pathogen prevalence is important for human health. As ticks are invading new areas northwards, information from these new areas are needed. Taiga tick (Ixodes persulcatus) populations have been recently found at Bothnian Bay, Finland. We assessed seasonal variation in questing abundance of ticks and their pathogen prevalence in coastal deciduous forests near the city of Oulu (latitudes 64–65°) in 2019. Methods We sampled ticks from May until September by cloth dragging 100 meters once a month at eight study sites. We calculated a…
Enterobacter cloacae administration induces hepatic damage and subcutaneous fat accumulation in high-fat diet fed mice.
2018
Accumulating evidence indicates that gut microbiota plays a significant role in obesity, insulin resistance and associated liver disorders. Family Enterobacteriaceae and especially Enterobacter cloacae strain B29 have been previously linked to obesity and hepatic damage. The underlying mechanisms, however, remain unclear. Therefore, we comprehensively examined the effects of E. cloacae subsp. cloacae (ATCC® 13047™) administration on host metabolism of mice fed with high-fat diet (HFD). C57BL/6N mice were randomly divided into HFD control, chow control, and E. cloacae treatment groups. The E. cloacae treatment group received live bacterial cells in PBS intragastrically twice a week, every ot…
The genome sequence of Blochmannia floridanus: Comparative analysis of reduced genomes
2003
Bacterial symbioses are widespread among insects, probably being one of the key factors of their evolutionary success. We present the complete genome sequence of Blochmannia floridanus , the primary endosymbiont of carpenter ants. Although these ants feed on a complex diet, this symbiosis very likely has a nutritional basis: Blochmannia is able to supply nitrogen and sulfur compounds to the host while it takes advantage of the host metabolic machinery. Remarkably, these bacteria lack all known genes involved in replication initiation ( dna A, pri A, and rec A). The phylogenetic analysis of a set of conserved protein-coding genes shows that Bl. floridanus is phylogenetically related to Buch…
Vigilancia de la susceptibilidad antibiótica y caracterización genotípica de aislados de Neisseria gonorrhoeae en la Comunidad Valenciana: proyecto m…
2020
Se calcula que cada año se producen más de 376 millones de nuevas infecciones transmitidas por vía sexual (ITS), representando las mismas un grave problema de salud pública a nivel mundial. Su incidencia se ha visto incrementada de forma alarmante durante las últimas dos décadas, causando perjuicios en la salud de aquellas personas que las padecen. Esta tendencia ascendente, similar en todos los países de Europa, responde a varias causas, muchas de ellas sociales. La gonorrea constituye, tras la infección producida por Chlamydia trachomatis, la segunda ITS más prevalente a nivel global. Tan solo en el año 2016, la Organización Mundial de la Salud (OMS) estimó en 86 millones los nuevos conta…
Ciclo del carbono y modelización biogeoquímica de un lago somero hipertrófico: la Albufera de Valencia
2015
Los lagos someros son uno de los ecosistemas acuáticos más numerosos a nivel global y hacen posible el desarrollo de multitud de actividades de interés económico y recreativo. En las últimas décadas, gran parte de estos lagos se han visto sujetos a un proceso de eutrofización cultural que a menudo conlleva una transición desde un estado "claro" caracterizado por una alta transparencia del agua y gran abundancia de macrófitos, a un estado "turbio" caracterizado por una baja transparencia del agua, dominancia de fitoplancton y macrófitos sumergidos prácticamente ausentes. El cambio que experimentó la Albufera de Valencia al estado turbio a principios de los años 1970 como resultado de un inte…
Rho GTPases Are Involved in the Regulation of NF-κB by Genotoxic Stress
2001
A common cellular response to genotoxic agents and inflammatory cytokines is the activation of NF-kappaB. Here, we addressed the question of whether small GTPases of the Rho family are involved in the stimulation of NF-kappaB signaling by genotoxic agents or TNFalpha in HeLa cells. Inhibition of isoprenylation of Rho proteins by use of the HMG-CoA reductase inhibitor lovastatin attenuated UV-, doxorubicin-, and TNFalpha-induced degradation of IkappaBalpha as well as drug-stimulated DNA binding activity of NF-kappaB. Furthermore, NF-kappaB-regulated gene expression stimulated by either UV irradiation or treatment with TNFalpha was abrogated by lovastatin pretreatment. This indicates that iso…