Andreas Lazaros Chryssafidis

Toxoplasma gondii is an intracellular protozoan with worldwide distribution and is of significant importance for One Health due to its zoonotic potential. Although its presence in terrestrial environments is well documented, little is known about its circulation and genetic diversity in the marine ecosystem. This study investigated the occurrence of T. gondii in seabirds rescued from the southern coast of Brazil, focusing on bioassay and molecular characterization. Tissue samples (the heart, brain, liver, lung, and pectoral muscle) from 76 seabirds were received. Of these, 26 were from Larus dominicanus, one Macronectes giganteus, one Pachyptila vittata, five Phalacrocorax brasilianus, two Procellaria aequinoctialis, two Puffinus puffinus, 35 Spheniscus magellanicus, two Sterna hirundo, and two Sula leucogaster. The samples of each bird were processed in pool for peptic digestion. The product of each digestion was inoculated (1 mL/SC) into three mice per bioassay/bird. DNA was extracted for molecular characterization using the PCR-RFLP technique with markers SAG1, 5'-SAG2, 3'-SAG2, Alt. SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico. Brain cysts were detected in 16 bioassays. The ToxoDB #170 genotype was identified as an isolate of kelp gull (Larus dominicanus) while another bioassay from the same species did not match the database, suggesting a previously undescribed genotype. Infection occurred through ingestion of sporulated oocysts present in the environment or in fish, bivalves, and crustaceans, which have demonstrated parasitic bioaccumulation. This work highlights the dispersal and infection capacity of different classes of T. gondii hosts and the role of birds as environmental sentinels for marine contamination.

Leishmaniasis is a parasitic disease caused by Leishmania spp., transmitted to hosts through the bite of female phlebotomine sandflies, with domestic dogs serving as reservoirs for the disease. Understanding the entomofauna is crucial for effective control of vector-borne diseases, such as leishmaniasis, because various environmental and climatic factors can influence sandfly presence and distribution. This study aimed to conduct a quantitative and qualitative survey of the entomofauna in urban and peri-urban areas of Lages, Santa Catarina, Brazil, and to analyze documented cases of canine leishmaniasis in the city, in response to the rising number of non-autochthonous cases in dogs. The lack of prior studies on this fauna in the municipality raises concerns for public health services. Nine areas were monitored over the course of one year, and clinical and epidemiological records of canine leishmaniasis in the city were analyzed. A total of 10,638 insects were collected, with no phlebotomine sandflies identified. All evaluated cases of canine leishmaniasis were classified as non-autochthonous based on the movement history of these animals and the absence of the disease vector in the municipality. This information may guide further control and prevention measures for leishmaniasis in the region, aligned with a One Health perspective.

Acinetobacter baumannii emerged as one of the most important pathogens for the development of new antimicrobials due to the worldwide detection of isolates resistant to all commercial antibiotics, especially in nosocomial infections. Biofilm formation enhances A. baumannii survival by impairing antimicrobial action, being an important target for new antimicrobials. Fluopsin C (FlpC) is an organocupric secondary metabolite with broad-spectrum antimicrobial activity. This study aimed to evaluate the antibiofilm activity of FlpC in established biofilms of extensively drug-resistant A. baumannii (XDRAb) and the effects of its combination with polymyxin B (PolB) on planktonic cells. XDRAb susceptibility profiles were determined by Vitek 2 Compact, disk diffusion, and broth microdilution. FlpC and PolB interaction was assessed using the microdilution checkerboard method and time–kill kinetics. Biofilms of XDRAb characterization and removal by FlpC exposure were assessed by biomass staining with crystal violet. Confocal Laser Scanning Microscopy was used to determine the temporal removal of the biofilms using DAPI, and cell viability using live/dead staining. The minimum inhibitory concentration (MIC) of FlpC on XDRAb was 3.5 µg mL⁻¹. Combining FlpC + PolB culminated in an additive effect, increasing bacterial susceptibility to both antibiotics. FlpC-treated 24 h biofilms reached a major biomass removal of 92.40 ± 3.38% (isolate 230) using 7.0 µg mL⁻¹ FlpC. Biomass removal occurred significantly over time through the dispersion of the extracellular matrix and decreasing cell number and viability. This is the first report of FlpC’s activity on XDRAb and the compound showed a promissory response on planktonic and sessile cells, making it a candidate for the development of a new antimicrobial product.

The increasing need for sustainable agricultural practices, combined with the demand for enhanced crop productivity, has led to a growing interest in utilizing microorganisms for biocontrol of diseases and pests, as well as for growth promotion. In Brazilian agriculture, the use of plant growth-promoting rhizobacteria (PGPR) and plant growth-promoting fungi (PGPF) has become increasingly prevalent, with a corresponding rise in the number of registered microbial inoculants each year. PGPR and PGPF occupy diverse niches within the rhizosphere, playing a crucial role in soil nutrient cycling and influencing a wide range of plant physiological processes. This review examines the primary mechanisms employed by these microbial agents to promote growth, as well as the strategy of co-inoculation to enhance product efficacy. Furthermore, we provide a comprehensive analysis of the microbial inoculants currently available in Brazil, detailing the microorganisms accessible for major crops, and discuss the market’s prospects for the research and development of novel products in light of current challenges faced in the coming years.

Toxoplasma gondii and Neospora caninum are two species of protozoa that belong to the Apicomplexa phylum and are distributed worldwide. T. gondii is one of the most extensively studied parasites due to its significant health implications. In this study, an investigation on the occurrence of T. gondii and N. caninum antibodies in dogs from a municipality on the southern coast of Santa Catarina, Brazil, and its associated risk factors were conducted. Blood samples were collected from 238 dogs, and a questionnaire was used to gather relevant information about the dogs, including their age, gender, breed, housing and habits. The serum samples were then subjected to indirect fluorescent antibody test (IFAT) using a cutoff of 1:64 and 1:50 to detect antibodies against T. gondii and N. caninum, respectively. The study’s findings revealed that the frequency of T. gondii was 23.1% (55/238), and no factors associated with infection in these animals were identified. However, the frequency of N. caninum was 4.2% (10/238), and the study identified the type of housing and environment in which the dogs lived as the factors that were associated with the infection. Stray animals and those that lived exclusively outdoors had a greater frequency of N. caninum. These results indicate that dogs from Laguna, Santa Catarina, Brazil, are exposed to T. gondii and N. caninum. As such, further studies are necessary to enhance the understanding of the nature of these protozoan infections in the municipality.

The demand for a more sustainable agriculture, coupled with the need for optimized crop productivity, has driven the use of microorganisms for the biocontrol of diseases and pests, as well as for growth promotion. The use of plant growth-promoting rhizobacteria (PGPR) and plant growth-promoting fungi (PGPF) in Brazilian production systems has become increasingly common, with the number of microbial inoculant registrations in the country growing every year. PGPR and PGPF occupy various niches in the rhizosphere, playing a crucial role in soil nutrient cycling, as well as influencing various plant physiological processes. In this review, we address the main mechanisms used by these microbial agents in growth promotion and the use of strain co-inoculation as a strategy to enhance the efficacy of these products. Subsequently, we conduct an analysis of the available inoculants in Brazil, detailing the microorganisms available for the main Brazilian crops, and the prospects of this market regarding research and development of new products for the coming years based on the current challenges faced.