285 resultados para COMMENSAL


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Calodium hepaticum (syn. Capillaria hepatica) é um nematódeo trichurídeo parasito de parênquima hepático de roedores e outros mamíferos. As infecções em humanos são raras, mas são relatadas em diversas regiões do mundo. Numerosos fatores contribuem para a distribuição desta zoonose, particularmente, uma densa população de roedores associada com ambientes urbanos com carência de saneamento básico, tais como aqueles encontrados em algumas cidades da região Norte do Brasil, como a cidade de Belém, localizada na Amazônia Oriental. Este estudo quantifica e demonstra a infecção por Calodium em roedores comensais sinantrópicos, de três bairros da cidade de Belém, Estado do Pará, com carência de saneamento público e alta incidência de leptospirose humana. Um total de 50 roedores foram capturados para análise (26 Rattus rattus e 24 R. norvegicus) e destes, 23 (10 R. rattus e 13 R. norvegicus) apresentaram típicas lesões hepáticas, macroscópicas, causadas por C. hepaticum. A análise de amostras por microscopia de luz direta e histopatológica do fígado dos roedores permitiu a identificação de espécimes desse parasito em fase larvar e adulta, além de numerosos ovos apresentando dupla casca estriada e dois tampões operculares. Este é o primeiro registro da ocorrência de C. hepaticum in R. rattus and R. norvegicus na região Amazônica, alertando para um considerável risco de transmissão para a população humana.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Pós-graduação em Odontologia - FOAR

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Pós-graduação em Microbiologia Agropecuária - FCAV

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Pós-graduação em Odontologia Restauradora - ICT

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Brucellosis remains as a public health concern worldwide. In domestic animals, the disease is characterized by reproductive disorders in male and female. Besides extensive use of serological tests and recent development of molecular biology techniques, microbiological culture of Brucella species is yet considered a “gold standard” method for diagnosis. Here, semen of 335 bovine bulls was subjected simultaneously to microbiological culture in Brucella agar, Farrell media, and CITA media to evaluate comparatively the best selective media for isolation of Brucella sp. Among all 335 samples, B. abortus B19 strain was isolated from semen of five (1.49%) bulls using the three selective media. However, Farrell media was considered the best selective media for microbiological diagnosis, because of allowed isolation of B. abortus B19 strain from bull semen without bacterial commensal or fungal contamination of plates.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: The intestinal microbiome (IM) has extensively been studied in the search for a link of bacteria with the cause of Crohn`s disease (CD). The association might result from the action of a specific pathogen and/or an eventual imbalance in bacterial species composition of the gut. The innumerous virulence associated markers and strategies described for adherent and invasive Escherichia coli (AIEC) have made them putative candidate pathogens for CD. IM of CD patients shows dysbiosis, manifested by the proliferation of bacterial groups such as Enterobacteriaceae and reduction of others such as Lactobacillus and Bifidobacterium. The augmented bacterial population comprising of commensal and/or pathogenic organisms super stimulates the immune system, triggering the inflammatory reactions responsible for the clinical manifestations of the disease. Considering the role played by IM in CD and the multiple variables influencing its species composition, resulting in differences among populations, the objective of this study was to determine the bacterial biodiversity in the mucosa associated microbiome of CD patients from a population not previously subject to this analysis, living in the middle west region of Sao Paulo state. Methods: A total of 4 CD patients and 5 controls subjects attending the Botucatu Medical School of the Sao Paulo State University (UNESP) for routine colonoscopy and who signed an informed consent were included in the study. A number of 2 biopsies, one from the ileum and other from any part of the terminal colon, were taken from each subject and immediately frozen at -70[degrees]C until DNA purification. The bacterial biodiversity was assessed by next generation (ion torrent) sequencing of PCR amplicons of the ribosomal DNA 16S V6 region (16S V6 rDNA). The bacterial identification was performed at the genus level, by alignment of the generated DNA sequences with those available at the ribosomal database project (RDP) website. Results: The overall DNA sequence output was based on an average number of 526,427 reads per run, matching 50 bacterial genus 16SrDNA sequences available at the RDB website, and 22 non matching sequences. Over 95% of the sequences corresponded to taxa belonging to the major phyla: Firmicutes, Bacterioidetes, Proteobacteria and Actinobacteria. Irrespective of the intestinal site analyzed, no case-control differences could be observed in the prevalence of Actinobacteria and Firmicutes. The prevalence of Proteobacteria was higher (40%) in the biopsies of control subjects as compared to that of DC patients (16%). For Bacterioidetes, the higher prevalence was observed among DC patients (33% as opposed to 14,5% in controls). The significance for all comparisons considered a p value < 0,05 in a Chi2 test. No mucosal site specific differences could be observed in IM comparisons of CD and control subjects. Conclusions: The rise in the number of Bacterioidetes observed here among CD patients seems to be in agreement with most of studies published thus far. Yet, the reduction in the number of Proteobacteria along with an apparently unaltered population of Actinobacteria and Firmicutes, which include the so called "beneficial" organisms Bifidobacterium and Lactobacillus were rather surprising. These data suggest that the analyses on the role of IM in CD should consider the multiple variables that may influence its species composition.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Poison baits are extensively used for commensal rodent control; considerable folk lore exists regarding the use of additives to induce rodents to come to and eat poison baits. This paper describes a rational evaluation of attractants and the influence of different odours in inducing Rattus norvegicus to feed at given locations. The influence of certain repellents was also examined. Tests consisted of attempts to induce rats to feed at non-preferred sites or to repel them from preferred sites. Place preference was the dominant factor in feeding by rats, and odours failed to influence feeding activity significantly.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The National Pest Control Association, which I represent, accepts for membership those persons or firms which are actively engaged in the performance of structural pest control services for hire to the public at large and which are in sympathy with the purposes of the Association. The pest control operator in this context might be called a commercial pest control operator to distinguish him from those doing similar work but who are employed by governmental agencies or within large commercial organizations. Pest control is a growing industry with a gross annual income of 300-350 million dollars. It is estimated to contain more than 5,000 firms employing about 25,000 productive workers. Many of these servicemen, possibly 15,000, are doing vertebrate pest control every day as they combat commensal rodents. A much smaller number, usually specialists or persons normally doing super¬visory work, are also engaged in the control of pest birds and a variety of miscellaneous vertebrates. With approximately 15,000 servicemen making at least 10 contacts a day with the public, it is readily apparent that whatever opportunity the general public has to judge the success or failure of vertebrate pest control practice is largely influenced by the work of the pest control industry.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The present study reports on a survey of the gelatinous zooplankton fauna (Cnidaria, Ctenophora and Thaliacea) from the proposed Baia da Babitonga marine protected area (southern Brazil; similar to 26 degrees S), based on collections from multiple sites over different seasons and from published literature. In order to sample both small and large gelatinous animals, plankton hauls (n = 255) and fishing trawls (n = 126) were employed. More than 20,000 organisms were studied, which, including literature data, totaled 48 species: one cubomedusa, three scyphomedusae, four siphonophores, 36 hydromedusae, two ctenophores, and two thaliaceans. Among these, the hydromedusae Cnidostoma fallax Vanhoffen and Helgicirrha sp. are recorded for the first time from the southwestern Atlantic coast and Paulinum sp. and Protiara sp. are recorded for the first time from the South Atlantic. A description of young stages of the hydromedusa Gossea brachymera Bigelow is presented and shows that Octobulbacea montehermosensis Zamponi is a junior synonym of the former. Although comprehensive local assessment of diverse taxonomic groups is still lacking, the high diversity observed herein underscores the importance of Ba a da Babitonga as a high priority site for conservation of regional marine biodiversity.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: Antimicrobial peptides are present in animals, plants and microorganisms and play a fundamental role in the innate immune response. Gomesin is a cationic antimicrobial peptide purified from haemocytes of the spider Acanthoscurria gomesiana. It has a broad-spectrum of activity against bacteria, fungi, protozoa and tumour cells. Candida albicans is a commensal yeast that is part of the human microbiota. However, in immunocompromised patients, this fungus may cause skin, mucosal or systemic infections. The typical treatment for this mycosis comprises three major categories of antifungal drugs: polyenes, azoles and echinocandins; however cases of resistance to these drugs are frequently reported. With the emergence of microorganisms that are resistant to conventional antibiotics, the development of alternative treatments for candidiasis is important. In this study, we evaluate the efficacy of gomesin treatment on disseminated and vaginal candidiasis as well as its toxicity and biodistribution. Results: Treatment with gomesin effectively reduced Candida albicans in the kidneys, spleen, liver and vagina of infected mice. The biodistribution of gomesin labelled with technetium-99 m showed that the peptide is captured in the kidneys, spleen and liver. Enhanced production of TNF-alpha, IFN-gamma and IL-6 was detected in infected mice treated with gomesin, suggesting an immunomodulatory activity. Moreover, immunosuppressed and C. albicans-infected mice showed an increase in survival after treatment with gomesin and fluconazole. Systemic administration of gomesin was also not toxic to the mice Conclusions: Gomesin proved to be effective against experimental Candida albicans infection. It can be used as an alternative therapy for candidiasis, either alone or in combination with fluconazole. Gomesin's mechanism is not fully understood, but we hypothesise that the peptide acts through the permeabilisation of the yeast membrane leading to death and/or releasing the yeast antigens that trigger the host immune response against infection. Therefore, data presented in this study reinforces the potential of gomesin as a therapeutic antifungal agent in both humans and animals.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The new pathway nitrate-nitrite-nitric oxide (NO) has emerged as a physiological alternative to the classical enzymatic pathway for NO formation from L-arginine. Nitrate is converted to nitrite by commensal bacteria in the oral cavity and the nitrite formed is then swallowed and reduced to NO under the acidic conditions of the stomach. In this study, we tested the hypothesis that increases in gastric pH caused by omeprazole could decrease the hypotensive effect of oral sodium nitrite. We assessed the effects of omeprazole treatment on the acute hypotensive effects produced by sodium nitrite in normotensive and L-NAME-hypertensive free-moving rats. In addition, we assessed the changes in gastric pH and plasma levels of nitrite, NOx (nitrate+ nitrite), and S-nitrosothiols caused by treatments. We found that the increases in gastric pH induced by omeprazole significantly reduced the hypotensive effects of sodium nitrite in both normotensive and L-NAME-hypertensive rats. This effect of omeprazole was associated with no significant differences in plasma nitrite, NOx, or S-nitrosothiol levels. Our results suggest that part of the hypotensive effects of oral sodium nitrite may be due to its conversion to NO in the acidified environment of the stomach. The increase in gastric pH induced by treatment with omeprazole blunts part of the beneficial cardiovascular effects of dietary nitrate and nitrite. (c) 2012 Elsevier Inc. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Group B Streptococcus (GBS), in its transition from commensal to pathogen, will encounter diverse host environments and thus require coordinately controlling its transcriptional responses to these changes. This work was aimed at better understanding the role of two component signal transduction systems (TCS) in GBS pathophysiology through a systematic screening procedure. We first performed a complete inventory and sensory mechanism classification of all putative GBS TCS by genomic analysis. Five TCS were further investigated by the generation of knock-out strains, and in vitro transcriptome analysis identified genes regulated by these systems, ranging from 0.1-3% of the genome. Interestingly, two sugar phosphotransferase systems appeared differently regulated in the knock-out mutant of TCS-16, suggesting an involvement in monitoring carbon source availability. High throughput analysis of bacterial growth on different carbon sources showed that TCS-16 was necessary for growth of GBS on fructose-6-phosphate. Additional transcriptional analysis provided further evidence for a stimulus-response circuit where extracellular fructose-6-phosphate leads to autoinduction of TCS-16 with concomitant dramatic up-regulation of the adjacent operon encoding a phosphotransferase system. The TCS-16-deficient strain exhibited decreased persistence in a model of vaginal colonization and impaired growth/survival in the presence of vaginal mucoid components. All mutant strains were also characterized in a murine model of systemic infection, and inactivation of TCS-17 (also known as RgfAC) resulted in hypervirulence. Our data suggest a role for the previously unknown TCS-16, here named FspSR, in bacterial fitness and carbon metabolism during host colonization, and also provide experimental evidence for TCS-17/RgfAC involvement in virulence.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Dendritische Zellen (DCs) nehmen eine Schlüsselrolle in unserem Immunsystem ein, indem DCs sowohl Immunität, als auch Toleranz induzieren können. Im Falle der Immunität sind DCs in der Lage die Differenzierung der verschiedenen T-Helferzellen, wie Th1-, Th2- und Th17-Zellen zu steuern und tragen so zu der Qualität einer Immunantwort bei. Auf der anderen Seite können DCs in Gegenwart von TGF-β, IDO und Retinsäure die Differenzierung von regulatorischen T-Zellen induzieren und tragen somit zur Aufrechterhaltung der peripheren Toleranz bei. Insbesondere in den Darm-assoziierten lymphatischen Geweben (GALT) müssen DCs unverhältnismäßige Immunantworten gegen harmlose Antigene aus der Nahrung und kommensale Bakterien verhindern, während gegen Pathogene schützende Immunantworten induziert werden müssen. Auf Grund dieser entgegengesetzten Funktionen der DCs wollten wir die molekularen Mechanismen der DCs untersuchen, die der Regulation von Immunität und Toleranz zu Grunde liegen. Insbesondere der Wnt-Signalweg ist für die Aufrechterhaltung der peripheren Toleranz im GALT von Bedeutung. Da die Casein Kinase 2 in diesem Signalweg entscheidend beteiligt ist, haben wir die CK2-Funktion konditionell, unter der Kontrolle des CD11c-Promotors, deletiert. Hierfür haben wir CD11c-cre Mäuse mit Mäusen verpaart, welche ein von loxP-Signalsequenzen flankiertes Ck2β Gen (CK2β-fl/fl) tragen. Die konditionelle Deletion der CK2-Funktion in DCs, führte zu einer verstärkten Expression der kostimulatorischen Moleküle (wie CD40, CD80, CD86) und der Zytokine IL-6 und IL-12 unter „steady-state“ Bedingungen. Detaillierte Untersuchungen der T-Zellen in CD11c-cre x CK2β-fl/fl Mäusen zeigte eine deutlich reduzierte naive T-Zellpopulation, einhergehend mit einer erhöhten Th1- und Th17-Differenzierung. Speziell in den mesenterialen Lymphknoten konnte eine höhere Frequenz von T-bet+ und Rorγt+ CD4+ T-Zellen gefunden werden, welche große Mengen der Zytokine IFN-γ und IL-17 nach ex vivo Stimulation produzierten. Weiterführende in vivo Versuche, hier wurde das Modell der oralen Toleranz gewählt, zeigten das eine CK2-Deletion in DCs die Induktion einer oralen Toleranz verhindert. Unsere Daten zeigen eindeutig, dass die CK2 entscheidend in der Regulation der DC Homöostase und der Aufrechterhaltung der peripheren Toleranz beteiligt ist.