Publications by authors named "Rafaela G Ferrari"

8 Publications

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Virulence genes identification and characterization revealed the presence of the Yersinia High Pathogenicity Island (HPI) in Salmonella from Brazil.

Gene 2021 Jun 20;787:145646. Epub 2021 Apr 20.

Molecular & Analytical Laboratory Center, Faculty of Veterinary, Department of Food Technology, Universidade Federal Fluminense, Niterói, Brazil; Chemistry Institute, Food Science Program, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Center for Food Analysis (NAL-LADETEC), Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; National Institute of Health Quality Control, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.

Salmonella spp. is one of the major agents of foodborne disease worldwide, and its virulence genes are responsible for the main pathogenic mechanisms of this micro-organism. The whole-genome sequencing (WGS) of pathogens has become a lower-cost and more accessible genotyping tool providing many gene analysis possibilities. This study provided an in silico investigation of 129 virulence genes, including plasmidial and bacteriophage genes from Brazilian strains' public Salmonella genomes. The frequency analysis of the four most sequenced serovars and a temporal analysis over the past four decades was also performed. The NCBI sequence reads archive (SRA) database comprised 1077 Salmonella public whole-genome sequences of strains isolated in Brazil between 1968 and 2018. Among the 1077 genomes, 775 passed in Salmonella in silico Typing (SISTR) quality control, which also identified 41 different serovars in which the four most prevalent were S. Enteritidis, S. Typhimurium, S. Dublin, and S. Heidelberg. Among these, S. Heidelberg presented the most distinct virulence profile, besides presenting Yersinia High Pathogenicity Island (HPI), rare and first reported in Salmonella from Brazil. The genes mgtC, csgC, ssaI and ssaS were the most prevalent within the 775 genomes with more than 99% prevalence. On the other hand, the less frequent genes were astA, iucBCD, tptC and shdA, with less than 1% frequency. All of the plasmids and bacteriophages virulence genes presented a decreasing trend between the 2000 s and 2010 s decades, except for the phage gene grvA, which increased in this period. This study provides insights into Salmonella virulence genes distribution in Brazil using freely available bioinformatics tools. This approach could guide in vivo and in vitro studies besides being an interesting method for the investigation and surveillance of Salmonella virulence. Moreover, here we propose the genes mgtC, csgC, ssaI and ssaS as additional targets for PCR identification of Salmonella in Brazil due to their very high frequency in the studied genomes.
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http://dx.doi.org/10.1016/j.gene.2021.145646DOI Listing
June 2021

The COVID-19 pandemic in Brazil built on socioeconomic and political pillars.

Pathog Glob Health 2021 03 14;115(2):75-77. Epub 2021 Jan 14.

COVID-19 Research Group, Center for Food Analysis (NAL), Technological Development Support Laboratory (LADETEC), Cidade Universitária, Rio de Janeiro, Brazil.

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http://dx.doi.org/10.1080/20477724.2021.1874202DOI Listing
March 2021

The congenital toxoplasmosis burden in Brazil: Systematic review and meta-analysis.

Acta Trop 2020 Nov 29;211:105608. Epub 2020 Jun 29.

Pathology Laboratory, Department of Basic Health Sciences, State University of Maringá, Paraná, Brazil.

Congenital toxoplasmosis is a zoonosis caused by the intracellular Apicomplexa protozoan Toxoplasma gondii. This infection causes subclinical or clinical lesions, such as retinochoroiditis and central nervous system lesions. The severity of fetal infection is related to the stage of pregnancy and the efficacy of the gestational treatment on fetal infection, whether it is achieved, or if it starts early. South America is the region with the highest burden of congenital toxoplasmosis and the most pathogenic genotypes. Here, we present the results of a comprehensive systematic review and meta-analysis of the congenital toxoplasmosis in Brazil. PubMed, Web of Science, and CAPES databases were used to search for relevant studies that were published between 1 January 2007 and 31 December 2018. The final searching process yielded 21 papers. The studies accounted for 469 children with congenital toxoplasmosis. Of these, 269 (57%) had a diagnosis in the postnatal period. Concerning mothers, 209 (44.6%) underwent prenatal care, but 47 (22.5%) did not receive any drug for toxoplasmosis treatment. There were 226 (48.2%) children with retinochoroiditis; 83 (17.7%) with brain calcifications; 9 (1.9%) with neurosensory auditory dysfunction; and 2 (0.42%) with human immunodeficiency virus coinfection. A total of 460 (98%) children had a medical and multidisciplinary follow-up for at least one year and the most frequent genotype was #11(BRII), found in seven children. There was a statistical correlation between the mother's treatment and asymptomatic children. The gestational treatment seems to protects the fetus since children of mothers who received anti-T. gondii medications have a better prognosis. The retinochoroiditis was the main finding among children, followed by brain calcifications.
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http://dx.doi.org/10.1016/j.actatropica.2020.105608DOI Listing
November 2020

Type three secretion system in Salmonella Typhimurium: the key to infection.

Genes Genomics 2020 05 28;42(5):495-506. Epub 2020 Feb 28.

Molecular and Analytical Laboratory Center, Faculty of Veterinary, Department of Food Technology, Universidade Federal Fluminense, Niterói, Brazil.

Background: Type Three Secretion Systems (T3SS) are nanomachine complexes, which display the ability to inject effector proteins directly into host cells. This skill allows for gram-negative bacteria to modulate several host cell responses, such as cytoskeleton rearrangement, signal transduction, and cytokine production, which in turn increase the pathogenicity of these bacteria. The Salmonella enterica subsp. enterica serovar Typhimurium (ST) T3SS has been the most characterized so far. Among gram-negative bacterium, ST is one of enterica groups predicted to have two T3SSs activated during different phases of infection.

Objective: To comprise current information about ST T3SS structure and function as well as an overview of its assembly and hierarchical regulation.

Methods: With a brief and straightforward reading, this review summarized aspects of both ST T3SS, such as its structure and function. That was possible due to the development of novel techniques, such as X-ray crystallography, cryoelectron microscopy, and nano-gold labelling, which also elucidated the mechanisms behind T3SS assembly and regulation, which was addressed in this review.

Conclusion: This paper provided fundamental overview of ST T3SS assembly and regulation, besides summarized the structure and function of this complex. Due to T3SS relevance in ST pathogenicity, this complex could become a potential target in therapeutic studies as this nanomachine modulates the infection process.
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http://dx.doi.org/10.1007/s13258-020-00918-8DOI Listing
May 2020

Worldwide Epidemiology of Serovars in Animal-Based Foods: a Meta-analysis.

Appl Environ Microbiol 2019 07 1;85(14). Epub 2019 Jul 1.

Molecular and Analytical Laboratory Center, Department of Food Technology, Faculty of Veterinary, Federal Fluminense University, Niterói, Brazil

spp. are among the most important foodborne pathogens and the third leading cause of human death among diarrheal diseases worldwide. Animals are the primary source of this pathogen, and animal-based foods are the main transmission route to humans. Thus, understanding the global epidemiology of serovars is key to controlling and monitoring this bacterium. In this context, this study aimed to evaluate the prevalence and diversity of serovars in animal-based foods (beef, pork, poultry, and seafood) throughout the five continents (Africa, the Americas [North and Latin America], Asia, Europe, and Oceania). The meta-analysis consisted of a chemometric assessment (hierarchical cluster analysis and principal component analysis) to identify the main epidemiological findings, including the prevalence and diversity of the serovars in each matrix. Regarding the serovar distribution, Typhimurium presented a cosmopolitan distribution, reported in all four assessed matrices and continents; poultry continues to play a central role in the dissemination of the Enteritidis serovar to humans, and Anatum and Weltevreden were the most frequently found in beef and seafood, respectively. Additionally, we recommended careful monitoring of certain serovars, such as Derby, Agona, Infantis, and Kentucky. Finally, given the scientific data regarding the most frequently reported serovars and which matrices constitute the main vehicles for the transmission of this pathogen, control programs may be improved, and specific interventions may be implemented in an attempt to reduce the risk of this pathogen reaching humans. Salmonellosis is caused by spp. and is the third leading cause of death among food-transmitted diseases. This pathogen is commonly disseminated in domestic and wild animals, and the infection's symptoms are characterized by acute fever, nausea, abdominal pain, and diarrhea. The animals are the primary source of salmonellae, and animal-based foods are the main transmission route to humans. Therefore, data collected from these sources could contribute to future global interventions for effective control and surveillance of along the food chain. In light of this, the importance of our research is in identifying the prevalence of serovars in four animal-based food matrices (pork, poultry, beef, and seafood) and to evaluate the importance that each matrix has as the primary source of this pathogen to humans.
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http://dx.doi.org/10.1128/AEM.00591-19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6606869PMC
July 2019

Virulence Factors in Salmonella Typhimurium: The Sagacity of a Bacterium.

Curr Microbiol 2019 Jun 21;76(6):762-773. Epub 2018 May 21.

Department of Food Technology, Faculty of Veterinary, Molecular & Analytical Laboratory Center, Universidade Federal Fluminense, Niterói, Brazil.

Currently, Salmonella enterica Typhimurium (ST) is responsible for most cases of food poisoning in several countries. It is characterized as a non-specific zoonotic bacterium that can infect both humans and animals and although most of the infections caused by this microorganism cause only a self-limiting gastroenteritis, some ST strains have been shown to be invasive, crossing the intestinal wall and reaching the systemic circulation. This unusual pathogenicity ability is closely related to ST virulence factors. This review aims to portray the main virulence factors in Salmonella Typhimurium, in order to better understand the strategies that this pathogen uses to reach the systemic circulation and increase its infectivity in humans and animals. Thus, the most studied Salmonella pathogenicity islands in Salmonella Typhimurium were detailed as to the functions of their encoded virulence factors. In addition, available knowledge on virulence plasmid was also compiled, as well as the chromosome regions involved in the virulence of this bacterium.
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http://dx.doi.org/10.1007/s00284-018-1510-4DOI Listing
June 2019

Phenotypic and Genotypic Eligible Methods for Typhimurium Source Tracking.

Front Microbiol 2017 22;8:2587. Epub 2017 Dec 22.

Molecular and Analytical Laboratory Center, Department of Food Technology, Faculty of Veterinary, Universidade Federal Fluminense, Niterói, Brazil.

Salmonellosis is one of the most common causes of foodborne infection and a leading cause of human gastroenteritis. Throughout the last decade, serotype Typhimurium (ST) has shown an increase report with the simultaneous emergence of multidrug-resistant isolates, as phage type DT104. Therefore, to successfully control this microorganism, it is important to attribute salmonellosis to the exact source. Studies of source attribution have been performed to determine the main food/food-production animals involved, toward which, control efforts should be correctly directed. Hence, the election of a ST subtyping method depends on the particular problem that efforts must be directed, the resources and the data available. Generally, before choosing a molecular subtyping, phenotyping approaches such as serotyping, phage typing, and antimicrobial resistance profiling are implemented as a screening of an investigation, and the results are computed using frequency-matching models (i.e., Dutch, Hald and Asymmetric Island models). Actually, due to the advancement of molecular tools as PFGE, MLVA, MLST, CRISPR, and WGS more precise results have been obtained, but even with these technologies, there are still gaps to be elucidated. To address this issue, an important question needs to be answered: what are the currently suitable subtyping methods to source attribute ST. This review presents the most frequently applied subtyping methods used to characterize ST, analyses the major available microbial subtyping attribution models and ponders the use of conventional phenotyping methods, as well as, the most applied genotypic tools in the context of their potential applicability to investigates ST source tracking.
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http://dx.doi.org/10.3389/fmicb.2017.02587DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5744012PMC
December 2017

Ciprofloxacin susceptibility reduction of Salmonella strains isolated from outbreaks.

Braz J Microbiol 2010 Apr 1;41(2):497-500. Epub 2010 Jun 1.

Departamento de Ciência e Tecnologia, Centro de Ciências Agrárias , Universidade Estadual de Londrina, PR , Brasil.

The antimicrobial susceptibility of 212 Salmonella strains isolated from patients and foods was evaluated and 45% were found to be resistant to nalidixic acid. Nalidixic acid resistant strains showed a higher minimal inhibitory concentration for ciprofloxacin than sensitive strains. During the study an increase of strains with reduced susceptibility to ciprofloxacin was also observed.
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http://dx.doi.org/10.1590/S1517-838220100002000033DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3768671PMC
April 2010