Showing 3 results for Lopes
Hamid Staji, Alfreda Tonelli, Taghi Zahraei Salehi, Mariangela Iorio, Federica Lopes,
Volume 3, Issue 1 (1-2015)
Abstract
Introduction: In Iran, invasive nontyphoidal Salmonella (iNTS) disease causes severe bacteremic illness among children <5 years old. The global yearly incidence of iNTS disease in children was reported to be in the 3.4 (range 2.1-6.5) million cases, (overall incidence 49 cases (range 30-94) per 100,000 population), the iNTS case-fatality ratio (CFR) of 20% yielded 681,316 deaths annually. Methods: The microarray analysis enables identification of the strains that have the 90kb Salmonella typhimurium virulence plasmid, presence or absence of the Salmonella pathogenicity islands (SPIs), adherence factors and other virulence determinants. Twelve isolates of S. typhimurium obtained from faeces of children with gastroenteritis were analyzed by microarray technique. Results: The virulence plasmid was present in 83.33% of isolates and all the isolates contained the SPI-4 and SPI-5. None of the strains had the cytolethal distending toxin, cdtB. All strains were positive for rck and mig-14. The adherence genes were present in all the strains in the range of 51.55% to 73.20% of the adherence genes interrogated in the microarray. Two strains were the least pathogenic S. typhimurium. Conclusion: Microarray analysis proved to be a valuable tool in confirmation of serotyping results and genetic characterization of S. Typhimurium.
Luciano Rodrigo Lopes, Antonio Carlos da Silva Junior, Paulo Bandiera-Paiva, Jorge Casseb,
Volume 9, Issue 3 (9-2021)
Abstract
Introduction: HIV-1 gp120 V3 GPGR motif has an essential role in viral invasion, cell fusion, and pathogenesis but presents a significant variability that can implicate neutralizing antibodies and antiretroviral drug resistance. Methods: We performed a comprehensive analysis based on 259,288 HIV-1 gp120 amino acid sequences obtained from the Los Alamos National Laboratory (LANL) HIV Sequence Database to infer the global distribution of V3 tetrapeptide motifs. We calculated the frequencies and presented the main variants according to continents and countries. Furthermore, the clinical importance of the most distributed V3 motifs was detailed. Results: Our results showed GPGR and GPGQ as the most commonly found V3 motifs among more than five hundred V3 variant motifs. Motifs with clinical implications are widely distributed around the world. Within the most frequent V3 tetrapeptide motifs set, some variants enable the escape from fusion inhibitor drugs and neutralizing antibodies. Conclusion: Considering that an effective vaccine candidate should elicit broadly neutralizing antibodies while fusion inhibitor drug interaction requires conserved amino acids, the diversity of V3 motifs implicates a great challenge in developing an effective HIV-1 vaccine.
Luciano Rodrigo Lopes, Natália Carvalho de Lucca Pina, Antonio Carlos da Silva Junior, Paulo Bandiera-Paiva,
Volume 10, Issue 1 (3-2022)
Abstract
Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spilled over to humans via wild mammals, entering the host cell using angiotensin-converting enzyme 2 (ACE2) as receptor through Spike (S) protein binding. While SARS-CoV-2 became fully adapted to humans and globally spread, some mammal species were infected back. The present study evaluated the potential risk of mammals becoming hosts for SARS-CoV-2 through bioinformatics prediction based on ACE2 receptors. Methods: We used evolutionary bioinformatic approaches and comparative analysis of ACE2 critical residues that bind SARS-CoV-2 S-protein and predicted potential SARS-CoV-2 hosts among mammals and assessed their risk. Results: ACE2 phylogenetic tree placed primates close to rodents and rabbits. Felines, rodents, and rabbits had higher ACE2 similarities than human ACE2 (hACE2). Farmed animals, such as bovids, swine, and equids, had similar ACE2 compared to hACE2; however, these animals showed low SARS-CoV-2 susceptibility. Some cetaceans also presented high similarities in ACE2 key residues with hACE2. Conclusion: Here, we showed wild and domestic mammals with a low divergence of ACE2 compared to humans, discussing their possible chance of being infected, especially those animals kept as livestock or pets. Regarding the feasible transmission through contaminated water, cetaceans can be at risk of SARS-CoV-2 infection. Extensive surveillance of SARS-CoV-2 should be applied to prevent new coronavirus outbreaks and preserve mammals from infectious threats.
