1,721,002 research outputs found
Characterization ofMycoplasma agalactiaemembrane proteome
Full text linkMycoplasma agalactiae is the etiological agent of contagious agalactia, a serious disease of small ruminants characterized by mastitis, polyarthritis, keratoconjunctivitis, and abortion.
Mycoplasmas totally lack the cell wall, so membrane proteins are directly exposed to environment. To date, a limited number of M. agalactiae antigens have been described. The combination of 2-D PAGE and mass spectrometry is a well-established method for proteome studies; however, it is reported that standard 2-D PAGE lacks in resolution of hydrophobic and basic proteins, which are abundant in mycoplasmas membrane. Indeed, membrane proteins are poorly represented in total extracts maps.
In this study, the membrane proteome of M. agalactiae PG2T was characterized. The Triton X-114 fractionation allowed the enrichment for M. agalactiae PG2T membrane proteins. Liposoluble proteins were subjected to 2-D PAGE-MS, leading to the identification of 40 unique proteins. The differential expression of liposoluble proteins, among PG2T strain and two field isolates, was revealed by 2D DIGE.
The use of GeLC-MS/MS allowed to increase the coverage of the liposoluble proteome. A total of 194 unique proteins were identified, (26% of M. agalactiae PG2T genes) and subjected to gene ontology analysis for localization and function. Interestingly, the 11.5% of identified proteins derived from putative horizontal gene transfer events.
This work paves the way for the development of diagnostic and prophylaxis tools
Eating the Enemy: Mycoplasma Strategies to Evade Neutrophil Extracellular Traps (NETs) Promoting Bacterial Nucleotides Uptake and Inflammatory Damage
Full text linkNeutrophils are effector cells involved in the innate immune response against infection; they kill infectious agents in the intracellular compartment (phagocytosis) or in the extracellular milieu (degranulation). Moreover, neutrophils release neutrophil extracellular traps (NETs), complex structures composed of a scaffold of decondensed DNA associated with histones and antimicrobial compounds; NETs entrap infectious agents, preventing their spread and promoting their clearance. NET formation is triggered by microbial compounds, but many microorganisms have evolved several strategies for NET evasion. In addition, the dysregulated production of NETs is associated with chronic inflammatory diseases. Mycoplasmas are reduced genome bacteria, able to induce chronic infections with recurrent inflammatory symptoms. Mycoplasmas’ parasitic lifestyle relies on metabolite uptake from the host. Mycoplasmas induce NET release, but their surface or secreted nucleases digest the NETs’ DNA scaffold, allowing them to escape from entrapment and providing essential nucleotide precursors, thus promoting the infection. The presence of Mycoplasma species has been associated with chronic inflammatory disorders, such as systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, Crohn’s disease, and cancer. The persistence of mycoplasma infection and prolonged NET release may contribute to the onset of chronic inflammatory diseases and needs further investigation and insights
Detection and characterization of an avipoxvirus in a common Buzzard (Buteo buteo) in Italy using a multiple gene approach
No full textPoxvirus infections have been reported in domestic, captive, and wild avian hosts including many raptor species. A wild Common Buzzard (Buteo buteo) admitted to a wildlife veterinary clinic in Sardinia, Italy, showed multiple, wart-like proliferative cutaneous lesions on both legs. Histologically, there was ballooning degeneration and large intracytoplasmic inclusion bodies consistent with avipoxvirus (APV) infection. Diagnosis was confirmed by PCR detecting APV genes: P4b (locus fpv167), P35 (locus fpv140), and partial DNA polymerase. Phylogenetic analyses were performed to compare the detected virus with a panel of selected APVs. Analyses of P4b and DNA polymerase assigned the virus to clade A (fowlpox virus), subclade A7, grouping with many other APVs previously isolated in birds of prey. Further research should highlight the diversity of avian pox viral strains circulating among Common Buzzards as well as the phylogenetic role of locus fpv140 (P35) in comparison with the more-conserved P4b and DNA polymerase genes
Molecular identification of neglected zoonotic pathogens on biopsies of Leishmania-like skin lesions
No full textOvine Papillomaviruses: diversity, pathogenicity, and evolution
Full text linkThe family Papillomaviridae includes a plethora of viral species infecting virtually all vertebrates excluding amphibians, with astonishing impact on human and animal health. Although more than 250 species have been described in humans, the total number of papillomaviruses (PVs) discovered in animals does not reach up to this number. In animals, PV infections are mostly asymptomatic or can cause variable clinical conditions ranging from self-limiting papillomas and other cutaneous and mucosal benign lesions to cancer. Most of animal PV types have been discovered in cattle, dogs, horses, and cats with other farm host species remaining overlooked. In particular, the number of PV types so far identified in sheep is limited. This paper comprehensively reviews ovine PVs features, including viral taxonomy and evolution; genome organization; viral tropism and pathogenesis; macroscopical features and histopathological patterns, as well as available diagnostics tools. Data are critically presented and discussed in terms of impact on veterinary and public health. The development of future dedicated research is also discussed
Experimental infection with streptococcus uberis in sarda sheep: histopatholocical examination and inflammation characterization
No full text"\"AIM OF THE STUDY:. Streptococcus uberis (Su) is the main environmental pathogen that causes mastitis in dairy animals, the infection produces predominantly subclinical mastitis. The topic has been recently studied by experimental infection in goats (1). Knowledge of mastitis caused by Su in sheep are poor; we have reproduced experimentally this type of mastitis in order to understand the pathogenic mechanism, the characteristics of the inflammation and to investigate the innate immune response mediators released in milk by mammary epithelial cells.. MATERIAL & METHODS:. The experimental infection was carried out in 5 Sarda sheep, first-time pregnancy, the second month of lactation and free of mastitis; evaluated through clinical examination and microbiological culture of milk, the serum negativity for Su was also evaluated. The inoculum was carried out using 2 x 107 cfu of Su via the teat canal on the left half-udder of 4 sheep, in the animal control was inoculated sterile PBS. Samples of blood and milk was collected daily and, 6 days after, we proceeded to the euthanasia and autopsy of the animals, with particular attention of the breasts and lymph nodes. Samples of organ was taken from different districts, fixed in 4% formalin for histological examination, and frozen at -80°C .. RESULTS:. The establishment of infection was confirmed both clinically and by molecular methods, including PCR and FISH on mammary tissues. Proteomic investigation of the milk enabled to detect an enrichment in proteins involved in inflammation, chemotaxis of immune cells, and antimicrobial defense in infected animals, suggesting the consistent involvement of mammary epithelial cells in the innate immune response to pathogens (2). All infected animals showed an increased volume of lymph nodes of the inoculated half-udder. Histopathological grading score of mammary tissues highlighted a clear difference between infected and uninfected udder halves. The control animal and uninfected halves showed no signs of inflammation and the epithelium was intact.. CONCLUSIONS:. The infection causes a significant reduction in milk production in sheep and, if the pathogen can replicate undisturbed, may cause clinical mastitis. On the other hand subclinical infection is dangerous because infected animals serve as reservoirs. Further studies are needed to better understand the pathogenesis, the response of the immune system and characterize the strains of Su inducing mastitis\"
Bat Ecology and Microbiome of the Gut: A Narrative Review of Associated Potentials in Emerging and Zoonotic Diseases
No full textIn this review, we tentatively tried to connect the most recent findings on the bat microbiome and to investigate on their microbial communities, that may vary even in conspecific hosts and are influenced by host physiology, feeding behavior and diet, social interactions, but also by habitat diversity and climate change. From a conservation perspective, understanding the potentially negative and indirect effects of habitat destruction on animal microbiota can also play a crucial role in the conservation and management of the host itself. According to the One Health concept, which recognizes an interdependence between humans, animals, and the environment, bat microbiota represents an indicator of host and environmental health, besides allowing for evaluation of the risk of emerging infectious diseases. We noticed that a growing number of studies suggest that animal microbiota may respond in various ways to changes in land use, particularly when such changes lead to altered or deficient food resources. We have highlighted that the current literature is strongly focused on the initial phase of investigating the microbial communities found in Chiroptera from various habitats. However, there are gaps in effectively assessing the impacts of pathogens and microbial communities in general in animal conservation, veterinary, and public health. A deeper understanding of bat microbiomes is paramount to the implementation of correct habitat and host management and to the development of effective surveillance protocols worldwide
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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