Search results for "Bacteria"
showing 10 items of 4919 documents
Stochastic model for a biological complex system: analysis of the bacterial growth in food products
2012
The Physics of Complex Systems has recently taken a more and more important role in the description of natural systems because of the interactions, both deterministic and noisy, between such systems and the environment. In particular the noise plays a relevant role in biological systems, whose dynamics is strongly influenced by environmental variables subject to random fluctuations. In this work a stochastic model is exploited to reproduce the growth of bacteria in food of animal origin. Specifically the dynamics of a bacterial species, Listeria monocytogenes, is analyzed in the presence of lactic acid bacteria (LAB) during the period of the fermentation of meat products. The model, based o…
Borrelia burgdorferi Outer Membrane Vesicles Contain Antigenic Proteins, but Do Not Induce Cell Death in Human Cells
2022
Like many bacterial species, Borrelia burgdorferi, the pleomorphic bacterium that causes Lyme borreliosis, produces outer membrane vesicles (OMVs). Borrelial OMVs (BbOMVs) have been identified as containing virulence factors, such as outer surface proteins (Osps) A, B, and C, as well as DNA. However, the pathogenicity of BbOMVs in disease development is still unclear. In this study, we characterized purified BbOMVs by analyzing their size and immunolabeling for known antigenic markers: OspA, OspC, p39, and peptidoglycan. In addition, BbOMVs were cocultured with human non-immune cells for cytotoxicity analysis. The results demonstrated that, on average, the vesicles were small, ranging betwe…
Ekstracelulārās vezikulās ietvertās mikrobiālās RNS atklāšana cilvēku asins un urīna paraugos
2020
Gandrīz visi cilvēka šūnu tipi sekretē ekstracelulārās vezikulas (EVs), un tām ir svarīga loma starpšūnu komunikācijā. Jaunākie pētījumi liecina, ka komunikācija notiek arī starp cilvēka mikrobiotu un saimniekorganisma šūnām. Šajā pētījumā mēs parādām, ka no cilvēka asinīm un urīna izdalītās EVs satur RNS fragmentus no dažādiem mikroorganismiem. Visbiežāk sastopami baktēriju tipi un supertipi asinīs un urīnā bija Proteobacteria, PVC grupa un Terrabacteria. Lai noteiktu vai šo mikrobiālo transkriptu galvenais avots ir zarnu mikrobioms, mēs izstrādājām EV izdalīšanas metodi no cilvēku fēču paraugiem. Tālāk mēs plānojām veikt RNS sekvencēšanas (RNA-seq) analīzi EV, kas izdalītas no plazmas, ur…
Bacterial and chemical indicator of coastal water pollution.
1993
This study has been carried out to compare the presence of some organic compounds of long environmental persistance (OCLEP) and heavy metals, in sea water samples, with faecal pollution indicators. Along the Sicily coast line three sites with different grade of pollution (urban, agricultural, industrial) were sampled. 69 samples were obtained from October 1987 to May 1990. Only indicators of faecal pollution were found linked to human settlements, while the other investigated anthropogenic activity related substances were found independently from sampling area.
Characterization of bacterial community in indoor environment
2006
We report the presence of bacterial colonization in library environment and on the books housed, performing morphological and bacterial molecular analyses. Isolated bacterial colonies were characterised by 16S rRNA locus and ITS (16S-23S rRNA Intergenic Transcribed Spacer) amplification and sequencing. The results of SEM observation and molecular analysis showed the prevalent presence of bacteria belonging to the family Micrococcaceae. We distinguished Kocuria rosea, Arthrobacter nicotianae, Micrococcus luteus and Curtobacterium flaccumfaciens which shows high cellulolytic activity.
Type IV pili and their role in virulence in Vibrio vulnificus
2021
Las bacterias del género Vibrio, compuesto por mas de 100 especies, están presentes en la gran mayoría de los ecosistemas acuáticos alrededor del mundo. Estas bacterias son gram-negativas, aeróbicas y anaeróbicas facultativas, y cuentan con al menos un flagelo polar. Se pueden encontrar tanto como un organismo de vida libre en el agua, como habitando superficies bióticas y abióticas en forma de agregaciones inmóviles llamadas biofilms. Una gran cantidad de especies pertenecientes a este género son patógenas para los humanos, dentro de las cuales, las tres más importantes son, V. cholerae, V. parahaemolyticus, y V. vulnificus, debido a su elevada tasa de incidencia y gravedad de las infeccio…
Dextranos de bacterias lácticas aisladas de productos cárnicos: caracterización y aplicaciones
2015
153 p.-46 fig.-9 tab.-2 anexos
Estudio de las resistencias a los antimicrobianos de bacterias zoonóticas y comensales aisladas en alimentos de la provincia de Valencia
2022
Las enfermedades transmitidas por los alimentos constituyen un problema de salud pública creciente en todo el mundo. Dentro de este amplio espectro de enfermedades que pueden ser causadas por la ingesta de alimentos contaminados, las toxiinfecciones alimentarias son aquellas enfermedades que, además de ser transmitidas por los alimentos, son causadas por agentes biológicos o sus toxinas, y suponen uno de los peligros más importantes asociados al consumo de alimentos. Los costes sociales y económicos de estas enfermedades son difíciles de evaluar, ya que implican no sólo costes médicos de tratamiento y hospitalización y jornadas de trabajo perdidas, sino también, en muchos casos, daños irrev…
Bakteriofāgu terapijas iespējas
2016
Pārmērīga antibakteriālu līdzekļu lietošana veicina epidēmijas mēroga bakteriālās rezistences pieaugumu attīstītajās un attīstības valstīs. Bakteriālās rezistences pieaugums atdzīvina interesi par alternatīvām antibakteriālām terapijām. Viena no tām iesaista bakteriofāgus – vīrusus, kuriem piemīt spējas inficēt un vairoties baktēriju saimniekšūnās veicinot to lizēšanu. Ir plaši dokumentēta fāgu veikta vairāku rezistentu baktēriju izskaušana, tomēr nav skaidrs, caur kādiem mehānismiem tā tiek panākta. Tas apgrūtina regulējošo iestāžu atļauju izsniegšanu, lai ieviestu bakteriofāgu terapiju klīniskajā praksē. Bakalaura darba mērķis bija noskaidrot veselības aprūpes speciālistu (ārstu) viedokli…
Cooperation between Different CRISPR-Cas Types Enables Adaptation in an RNA-Targeting System
2021
CRISPR-Cas systems are immune systems that protect bacteria and archaea against their viruses, bacteriophages. Immunity is achieved through the acquisition of short DNA fragments from the viral invader’s genome.