105 research outputs found
Brain and lung cryptococcoma and concurrent corynebacterium pseudotuberculosis infection in a goat: a case report
A four-year-old male goat with a history of neurological disorder was euthanized. It presented uncommon nodules in the brain and lungs associated with multiple abscesses, predominantly in the spleen and liver. Histological examination of brain and lung sections revealed yeast forms confirmed to be Cryptococcus gattii after a combination of isolation and polymerase chain reaction (PCR) procedures. Moreover, Corynebacterium pseudotuberculosis infection was diagnosed by PCR of samples from the lung, spleen and liver. The present report highlights the rare concurrent infection of C. gatti and C. pseudotuberculosis in an adult goat from São Paulo state, Brazil, and indicates the necessity of surveillance in the treatment of goats with atypical pulmonary infections associated with neurological disorders.São Paulo State University School of Veterinary Medicine Laboratory of Animal Pathology and MicrobiologyFederal University of Minas Gerais Laboratory of Cellular and Molecular GeneticsFederal University of São Paulo Department of MicrobiologyUNIFESP, Department of MicrobiologySciEL
Main features of DNA-based immunization vectors
DNA-based immunization has initiated a new era of vaccine research. One of the main goals of gene vaccine development is the control of the levels of expression in vivo for efficient immunization. Modifying the vector to modulate expression or immunogenicity is of critical importance for the improvement of DNA vaccines. The most frequently used vectors for genetic immunization are plasmids. In this article, we review some of the main elements relevant to their design such as strong promoter/enhancer region, introns, genes encoding antigens of interest from the pathogen (how to choose and modify them), polyadenylation termination sequence, origin of replication for plasmid production in Escherichia coli, antibiotic resistance gene as selectable marker, convenient cloning sites, and the presence of immunostimulatory sequences (ISS) that can be added to the plasmid to enhance adjuvanticity and to activate the immune system. In this review, the specific modifications that can increase overall expression as well as the potential of DNA-based vaccination are also discussed
Unveiling fungal community structure along different levels of anthropic disturbance in a South American subtropical lagoon
Studies of fungal communities through amplicon metagenomics in aquatic environments, particularly in freshwater ecosystems, are still relatively recent. Unfortunately, many of these water bodies are facing growing threats from human expansion, such as effluent discharge from various human activities. As a result, these effluents have the potential to significantly alter the characteristics of water bodies and, subsequently, impact the diversity of their resident microorganisms. In this context, our objective was to investigate whether the fungal community structure varies according to the presence of different anthropic disturbances. We expect (i) the diversity of fungi will be greater and (ii) more specific unique operational taxonomic units (OTUs) related to each ecotonal system will be found compared to other sites of a lagoon. The study was conducted in the Tramandaí Lagoon (subtropical southern Brazil) at four distinct sampling points (estuary, middle of the lagoon, crop field area, and near a residential area where the Tramandaí River flows into the lagoon). As expected, the estuary and residential zones, which are ecotones, exhibited greater fungal diversity and more specific OTUs compared to the middle of the lagoon and crop field area. Moreover, a substantial proportion of fungal taxa could not be identified at the genus level, with many only classified at the phylum level, indicating potential new lineages. These findings underscore our limited understanding of the subtropical freshwater mycobiota
The expression of plasmid mediated afimbrial adhesin genes in an avian septicemic Escherichia coli strain
An Escherichia coli strain (SEPT13) isolated from the liver of a hen presenting clinical signs of septicaemia had a LD50 of 4.0 × 105 CFU/ml in one-day-old chickens, expressed Ia, Ib, E1, E3, K and B colicins and aerobactin. The strain was ampicillin and streptomycin resistant, and found to have fimA, csgA and tsh DNA related sequences; it could adhere to and invade HEp-2 and tracheal epithelial cells, expressed fimbriae (observed by electron microscopy), and had five plasmids of 2.7, 4.7, 43, 56, and 88 MDa. Transposon mutagenesis of strain SEPT13, with transposon TnphoA, resulted in a mutant strain named ST16 that had a LD50 of 1.2 × 1012 CFU/ml. All other biological characteristics of strain ST16 were the same as those detected for strain SEPT13 except for the migration of an 88 MDa plasmid to the 93 MDa position indicating the insertion of the transposon into the 88 MDa plasmid. The 93 MDa plasmid of strain ST16 was transferred, by electroporation assay, to non-pathogenic receptor strains (E. coli strains K12 MS101 and HB101), resulting in transformant strains A and B, respectively. These strains exhibited adhesion properties to in vitro cultivated HEp-2 cells but did not have the capacity for invasion. The adherence occurred despite the absence of fimbriae; this finding suggests that the 88 MDa plasmid has afimbrial adhesin genes
A computational method for the identification of dengue, zika and chikungunya virus species and genotypes
In recent years, an increasing number of outbreaks of Dengue, Chikungunya and Zika viruses have been reported in Asia and the Americas. Monitoring virus genotype diversity is crucial to understand the emergence and spread of outbreaks, both aspects that are vital to develop effective prevention and treatment strategies. Hence, we developed an efficient method to classify virus sequences with respect to their species and sub-species (i.e. serotype and/or genotype). This tool provides an easy-to-use software implementation of this new method and was validated on a large dataset assessing the classification performance with respect to whole-genome sequences and partial-genome sequences.publishersversionpublishe
The Space-Exposed Kombucha Microbial Community Member Komagataeibacter oboediens Showed Only Minor Changes in Its Genome After Reactivation on Earth
Komagataeibacter is the dominant taxon and cellulose-producing bacteria in the Kombucha Microbial Community (KMC). This is the first study to isolate the K. oboediens genome from a reactivated space-exposed KMC sample and comprehensively characterize it. The space-exposed genome was compared with the Earth-based reference genome to understand the genome stability of K. oboediens under extraterrestrial conditions during a long time. Our results suggest that the genomes of K. oboediens IMBG180 (ground sample) and K. oboediens IMBG185 (spaceexposed) are remarkably similar in topology, genomic islands, transposases, prion-like proteins, and number of plasmids and CRISPR-Cas cassettes. Nonetheless, there was a difference in the length of plasmids and the location of cas genes. A small difference was observed in the number of protein coding genes. Despite these differences, they do not affect any genetic metabolic profile of the cellulose synthesis, nitrogen-fixation, hopanoid lipids biosynthesis, and stress-related pathways. Minor changes are only observed in central carbohydrate and energy metabolism pathways gene numbers or sequence completeness. Altogether, these findings suggest that K. oboediens maintains its genome stability and functionality in KMC exposed to the space environment most probably due to the protective role of the KMC biofilm. Furthermore, due to its unaffected metabolic pathways, this bacterial species may also retain some promising potential for space applications
Lipidomic Analysis Reveals Serum Alteration of Plasmalogens in Patients Infected With ZIKA Virus
Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the Flavivirus genus of the Flaviviridae family. Since the large outbreaks in French Polynesia in 2013–2014 and in Brazil in 2015, ZIKV has been considered a new public health threat. Similar to other related flavivirus, ZIKV is associated with mild and self-limiting symptoms such as rash, pruritus, prostration, headache, arthralgia, myalgia, conjunctivitis, lower back pain and, when present, a short-term low grade fever. In addition, ZIKV has been implicated in neurological complications such as neonatal microcephaly and Guillain–Barré syndrome in adults. Herein, serum lipidomic analysis was used to identify possible alterations in lipid metabolism triggered by ZIKV infection. Patients who presented virus-like symptoms such as fever, arthralgia, headache, exanthema, myalgia and pruritus were selected as the control group. Our study reveals increased levels of several phosphatidylethanolamine (PE) lipid species in the serum of ZIKV patients, the majority of them plasmenyl-phosphatidylethanolamine (pPE) (or plasmalogens) linked to polyunsaturated fatty acids. Constituting up to 20% of total phospholipids in humans, plasmalogens linked to polyunsaturated fatty acids are particularly enriched in neural membranes of the brain. The biosynthesis of plasmalogens requires functional peroxisomes, which are important sites for viral replication, including ZIKV. Thus, increased levels of plasmalogens in serum of ZIKV infected subjects suggest a link between ZIKV life cycle and peroxisomes. Our data provide important insights into specific host cellular lipids that are likely associated with ZIKV replication and may serve as platform for antiviral strategy against ZIKV
- …