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1.
J Virol ; : e0051324, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38752754

ABSTRACT

Marseilleviruses (MsV) are a group of viruses that compose the Marseilleviridae family within the Nucleocytoviricota phylum. They have been found in different samples, mainly in freshwater. MsV are classically organized into five phylogenetic lineages (A/B/C/D/E), but the current taxonomy does not fully represent all the diversity of the MsV lineages. Here, we describe a novel strain isolated from a Brazilian saltwater sample named Marseillevirus cajuinensis. Based on genomics and phylogenetic analyses, M. cajuinensis exhibits a 380,653-bp genome that encodes 515 open reading frames. Additionally, M. cajuinensis encodes a transfer RNA, a feature that is rarely described for Marseilleviridae. Phylogeny suggests that M. cajuinensis forms a divergent branch within the MsV lineage A. Furthermore, our analysis suggests that the common ancestor for the five classical lineages of MsV diversified into three major groups. The organization of MsV into three main groups is reinforced by a comprehensive analysis of clusters of orthologous groups, sequence identities, and evolutionary distances considering several MsV isolates. Taken together, our results highlight the importance of discovering new viruses to expand the knowledge about known viruses that belong to the same lineages or families. This work proposes a new perspective on the Marseilleviridae lineages organization that could be helpful to a future update in the taxonomy of the Marseilleviridae family. IMPORTANCE: Marseilleviridae is a family of viruses whose members were mostly isolated from freshwater samples. In this work, we describe the first Marseillevirus isolated from saltwater samples, which we called Marseillevirus cajuinensis. Most of M. cajuinensis genomic features are comparable to other Marseilleviridae members, such as its high number of unknown proteins. On the other hand, M. cajuinensis encodes a transfer RNA, which is a gene category involved in protein translation that is rarely described in this viral family. Additionally, our phylogenetic analyses suggested the existence of, at least, three major Marseilleviridae groups. These observations provide a new perspective on Marseilleviridae lineages organization, which will be valuable in future updates to the taxonomy of the family since the current official classification does not capture all the Marseilleviridae known diversity.

2.
Anaerobe ; : 102861, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38729514

ABSTRACT

OBJECTIVE: This study aimed to evaluate the fecal shedding of C. difficile in calves on farms in Sao Paulo State, Brazil. MATERIALS AND METHODS: Fecal samples (n=300) were collected from diarrheic (n=78) and nondiarrheic (n=222) calves less than 60 days of age from 20 farms. Fecal samples were inoculated into enrichment broth supplemented with taurocholate and cultured under anaerobic conditions. Colonies suspected to be C. difficile were harvested for DNA extraction and then multiplex PCR for the detection of genes encoding toxins A and B and binary toxins. All toxigenic isolates were ribotyped and tested for antimicrobial susceptibility, and five selected strains were subjected to whole-genome sequencing to determine their sequence type. RESULTS AND DISCUSSION: C. difficile was isolated from 29.3% (88/300) of the samples. All toxigenic isolates (17/88, 19.3%) were classified as ribotypes RT046 (13/17 -79.47%, A+B+ CDT-) and RT126 (4/17=20.53%, A+B+ CDT+). The sequenced strains from RT046 were classified as ST35 (Clade 1), while those from RT126 were classified as ST11 (Clade 5). No associations between the epidemiological factors in any of the groups and C. difficile isolation were observed. Most of the toxigenic isolates (16/17=94.41%) were classified as multidrug-resistant. Calves can be an important source of toxigenic C. difficile strains, including multidrug-resistant isolates from ribotypes commonly observed in humans.

3.
Pathogens ; 13(2)2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38392846

ABSTRACT

In this new methodology, plasmonic ELISA (pELISA) was used to detect Circovirus porcine2 (PCV2) in serum samples without the need for plate reading equipment. This process occurs by adapting the conventional ELISA test with gold nanoparticles (AuNPs) to promote a color change on the plate and quickly identify this difference with the naked eye, generating a dark purple-gray hue when the samples are positive and red when the samples are negative. The technique demonstrated high efficiency in detecting samples with a viral load ≥ 5 log10 copies/mL. Plasmonic ELISA offers user-friendly, cost-effective, and reliable characteristics, making it a valuable tool for PCV2 diagnosis and potentially adaptable for other pathogen detection applications.

4.
Int J Parasitol ; 53(13): 739-749, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37673202

ABSTRACT

Santa Ines (SI) and Ile de France (IF) sheep are known to be resistant and susceptible to Haemonchus contortus infection, respectively. Several studies have shown some genes as potential biological markers for sheep resistance against gastrointestinal nematodes using molecular tools, including transcriptomic analysis. In this study, we sequenced the polyadenylated RNA of the abomasal tissue of SI and IF suckling lambs to identify mucosa-specific transcript alterations between breeds artificially infected with H. contortus. Naïve SI (n = 4) and IF (n = 4) lambs were artificially infected every other day, over a period of 52 days, from 14 to 66 days old, with a total of 5,400 H. contortus infective larvae. Fundic abomasal tissue samples were collected at 68 days old, and submitted to high-throughput RNA sequencing (RNA-seq). Differential expression analysis (P value < 0.001 and False Discovery Rate (FDR) < 0.05) between SI and IF samples identified 292 genes, most of which showed greater expression in SI lambs. To help annotate and assign possible function to differentially expressed genes (DEGs), we used previously available single-cell RNA-seq (scRNA-seq) data from ovine abomasal mucosa to putatively identify cell types and possible mechanisms involved in resistance to H. contortus. In particular, genes associated with endothelial and tuft cells showed the greatest increases in expression in SI relative to IF lambs. SI lambs had higher percentages of tuft cells than IF lambs in the fundic abomasal mucosa. Although we found innate immunity (cell-mediated in mucosa) acting as a protagonist in impairing H. contortus infection, a stronger acquired immune response was being modulated at an earlier stage by SI lambs. We suggest that the complex connection between innate and adaptive immunity is via cellular antigen processing and presentation (APP). Based on comparison with scRNA-seq data, SI lambs showed a robust APP mechanism characterized mainly by greater T cell APP, macrophage differentiation, and cytokine signalling. We identified potential mechanisms and markers to advance knowledge for selection of H. contortus resistance at a very early age, in SI as well as in other commercial sheep breeds.


Subject(s)
Haemonchiasis , Haemonchus , Sheep Diseases , Sheep , Animals , Haemonchus/genetics , RNA-Seq , Immunity, Innate , Adaptive Immunity , Disease Susceptibility , Sheep Diseases/genetics , Haemonchiasis/genetics , Haemonchiasis/veterinary , Feces , Parasite Egg Count/veterinary
5.
Sci Rep ; 13(1): 9918, 2023 06 19.
Article in English | MEDLINE | ID: mdl-37336969

ABSTRACT

Obesity in adolescents has reached epidemic proportions and is associated with the inflammatory response and viral infections. The aim of this study was to understand the profile of inflammatory cytokines and chemokines associated with the inflammatory response and metabolic syndrome (MetS) in obese adolescents with positive serology for adenovirus 36 (ADV36). Thirty-six overweight, 36 obese, and 25 severe obesity adolescents aged 10 to 16 years were included in the study. The following variables were analyzed: sex, age, body mass index (BMI), blood pressure, total cholesterol and fractions, triglycerides, glucose, serum cytokine concentrations, and ADV36 antibodies. Cytokines and chemokines were quantified by cytometry and ADV36 serology was determined by enzyme-linked immunosorbent assay (ELISA). The results showed higher levels of the cytokines interleukin-1beta (IL-1ß), IL-6, IL-10 and of the chemokine interferon-gamma-inducible protein 10 (IP-10) in severe obesity adolescents compared to the obese and overweight groups, as well as in the group with MetS compared to the group without this syndrome. The frequency of ADV36-positive individuals did not differ between groups. The findings revealed differences in BMI between the obese and severe obesity groups versus the overweight group in the presence of positivity for ADV36, suggesting an association with weight gain and possibly MetS installation.


Subject(s)
Adenoviridae Infections , Metabolic Syndrome , Obesity, Morbid , Pediatric Obesity , Adolescent , Humans , Adenoviridae , Overweight , Cytokines , Adenoviridae Infections/epidemiology , Body Mass Index
6.
Cells ; 12(7)2023 04 06.
Article in English | MEDLINE | ID: mdl-37048165

ABSTRACT

The COVID-19 pandemic was triggered by the coronavirus SARS-CoV-2, whose peak occurred in the years 2020 and 2021. The main target of this virus is the lung, and the infection is associated with an accentuated inflammatory process involving mainly the innate arm of the immune system. Here, we described the induction of a pulmonary inflammatory process triggered by the intranasal (IN) instillation of UV-inactivated SARS-CoV-2 in C57BL/6 female mice, and then the evaluation of the ability of vitamin D (VitD) to control this process. The assays used to estimate the severity of lung involvement included the total and differential number of cells in the bronchoalveolar lavage fluid (BALF), histopathological analysis, quantification of T cell subsets, and inflammatory mediators by RT-PCR, cytokine quantification in lung homogenates, and flow cytometric analysis of cells recovered from lung parenchyma. The IN instillation of inactivated SARS-CoV-2 triggered a pulmonary inflammatory process, consisting of various cell types and mediators, resembling the typical inflammation found in transgenic mice infected with SARS-CoV-2. This inflammatory process was significantly decreased by the IN delivery of VitD, but not by its IP administration, suggesting that this hormone could have a therapeutic potential in COVID-19 if locally applied. To our knowledge, the local delivery of VitD to downmodulate lung inflammation in COVID-19 is an original proposition.


Subject(s)
COVID-19 , Pneumonia , Mice , Animals , Female , Humans , SARS-CoV-2 , Vitamin D/pharmacology , Pandemics , Mice, Inbred C57BL , Vitamins , Mice, Transgenic
7.
Viruses ; 15(4)2023 04 10.
Article in English | MEDLINE | ID: mdl-37112924

ABSTRACT

Each year, the Brazilian Society for Virology promotes a national meeting during the second semester of the year. In October 2022, the 33rd meeting took place at Arraial da Ajuda, Porto Seguro, Bahia, in-person:.this was the first in-person meeting since 2019, as the 2020 and 2021 events occurred online due to the issues imposed by COVID-19. It was a great pleasure for the whole audience to return to an in-person event, which certainly improved the interactions between the attendees in all ways. As usual, the meeting involved massive participation of undergraduate, graduate, and postdoc students, and several noteworthy international researchers were present. During five afternoons and evenings, attendees could discuss and learn about the most recent data presented by distinguished scientists from Brazil and other countries. In addition, young virology researchers from all levels could present their latest results as oral presentations and posters. The meeting covered all virology areas, with conferences and roundtables about human, veterinary, fundamental, environmental, invertebrate, and plant virology. The costs associated with attending the in-person event caused a slight reduction in the number of attendees compared to the two online events. However, even with this issue, the attendance was impressive. The meeting successfully achieved its most important goals: inspiring young and senior scientists and discussing high-quality, up-to-date virology research.


Subject(s)
COVID-19 , Humans , Brazil , Societies, Scientific , Virology
8.
Trop Med Infect Dis ; 8(3)2023 Mar 17.
Article in English | MEDLINE | ID: mdl-36977178

ABSTRACT

Bovine leptospirosis causes economic losses and raises public health concerns. It is possible that there are peculiarities in the epidemiology of leptospirosis in regions with a semiarid climate, such as the Caatinga biome in Brazil, where the climate is hot and dry, and the etiological agent require alternative routes of transmission. This study aimed to close knowledge gaps to the diagnosis and epidemiology of Leptospira spp. infection in cows from the Caatinga biome, Brazil. Samples of the blood, urinary tract (urine, bladder and kidney) and reproductive tract (vaginal fluid, uterus, uterine tube, ovary and placenta) were collected from 42 slaughtered cows. Diagnostic tests included were the microscopic agglutination test (MAT), polymerase chain reaction (PCR) and bacterial isolation. Anti-Leptospira spp. antibodies were found in 27 (64.3%) of the animals analyzed using MAT at a 1:50 dilution (cut-off 50), while 31 (73.8%) animals had at least one organ/fluid where the presence of Leptospira spp. DNA was identified, and 29 animals (69%) were positive at bacteriological culture. The highest sensitivity values for MAT were obtained at the cut-off point of 50. In conclusion, even under hot and dry climate conditions, it is possible that Leptospira spp. can spread through alternative routes such as venereal transmission; moreover, a cut-off of 50 is recommended for the serological diagnosis of cattle from the Caatinga biome.

9.
Tuberculosis (Edinb) ; 139: 102319, 2023 03.
Article in English | MEDLINE | ID: mdl-36764074

ABSTRACT

The objective of this study was to report the occurrence of Mycobacterium avium subspecies paratuberculosis (MAP) in dairy goats, via description of their clinical presentation, histopathological findings, and molecular identification of the infectious agent. Screening was performed using IS900 real-time PCR (qPCR) in milk samples from 179 properties in the semiarid of Northeast region of Brazil. Pooled milk samples from all lactating goats from processing plants were submitted to molecular diagnosis. One property had a positive result at qPCR. The production unit which had the positive sample for MAP was located, and an on-site visit to this property was performed to collect individual milk samples, seven of which tested MAP positive by IS900 qPCR. With permission from the owner, two goats (Animal 1 was positive and Animal 2 was negative on first qPCR for MAP) were acquired and euthanized. Animals 1 and 2 had milk and portions of the duodenum, ileum, colon, and mesenteric lymph nodes positive at qPCR for MAP. Animal 1 also had MAP DNA detected in part of the jejunum and cecum. In animal 2, the ileocecal valve tested positive. MAP was not detected in the blood or feces of either animal; however; it was confirmed for the association of clinical findings, histopathology, and qPCR. The gene IS900 from the positive samples were sequenced and showed a 99% similarity with MAP. The MAP was identified for the first time in the goat milk and tissues in the semiarid region of Northeast Brazil.


Subject(s)
Mycobacterium avium subsp. paratuberculosis , Mycobacterium tuberculosis , Paratuberculosis , Animals , Female , Mycobacterium avium subsp. paratuberculosis/genetics , Paratuberculosis/diagnosis , Paratuberculosis/epidemiology , Paratuberculosis/microbiology , Lactation , Goats
10.
Microorganisms ; 12(1)2023 Dec 29.
Article in English | MEDLINE | ID: mdl-38257898

ABSTRACT

The aim of this study was to investigate the coinfection of feline retroviruses (feline immunodeficiency virus-FIV, and the feline leukemia virus-FeLV) with Leishmania infantum and Toxoplasma gondii and the factors associated with these pathogens in domestic cats from Mossoró, a city endemic for canine and human leishmaniasis situated in the semiarid region of Northeast Brazil. Blood samples from 120 cats were collected, and an epidemiological questionnaire was applied to investigate the risk factors associated with the infections. Retroviruses, L. infantum, and T. gondii infections were assessed using a point-of-care ELISA and quantitative PCR (qPCR), indirect fluorescent antibody test (IFAT) and qPCR, and IFAT, respectively. The overall seroprevalences observed were 35% (95% CI = 27.0-43.8%) for FIV, 0.8% (95% CI = 0.1-4.5%) for FeLV, 25.8% (95% CI = 18.8-34.3%) for T. gondii, and 4.2% (95% CI = 1.7-9.3%) for L. infantum. Coinfection with FIV and L. infantum was observed in 2.5% (3/120) of the assessed cats, while 12.5% (15/120) were coinfected with FIV and T. gondii. No significant association was found among the investigated agents (p > 0.05). The factors associated with FIV infection in the multivariable analysis were male sex and age above 78 months. The findings of this study demonstrated a high rate of FIV infection in cats from the Brazilian semiarid region and the exposure of these animals to zoonotic and opportunistic agents. Due to the immunosuppressive potential of FIV, cats infected with this retrovirus should be screened for coinfections with L. infantum and T. gondii, and preventative measures should be adopted.

11.
Mem Inst Oswaldo Cruz ; 117: e220012, 2022.
Article in English | MEDLINE | ID: mdl-36074421

ABSTRACT

BACKGROUND: Zika virus (ZIKV) was discovered in 1947 with the virus isolation from Rhesus monkey (Macaca mulatta) in Uganda forest, Africa. Old World Primates are involved in a sylvatic cycle of maintenance of this arbovirus, however a limited knowledge about the role of New World primates in ZIKV transmission cycles has been established. OBJECTIVE: This work aimed to investigate the presence of enzootic circulation of ZIKV in New World Primates from three Brazilian states: São Paulo, Paraíba, and Paraná. METHODS: We analyzed 100 non-human primate samples collected in 2018 and 2020 from free-ranging and captive environments from São Paulo (six municipalities belonging to Sorocaba region), Paraíba (João Pessoa municipality), and Paraná (Foz do Iguaçu municipality) using reverse transcriptase quantitative polymerase reaction (RT-qPCR) assays, indirect enzyme-linked immunosorbent assay (ELISA), and plaque reduction neutralization test (PRNT). FINDINGS: All samples (n = 141) tested negative for the presence of ZIKV genome from tissue and blood samples. In addition, all sera (n = 58) from Foz do Iguaçu' non-human primates (NHPs) were negative in serological assays. MAIN CONCLUSION: No evidence of ZIKV circulation (molecular and serological) was found in neotropical primates. In addition, the absence of antibodies against ZIKV suggests the absence of previous viral exposure of NHPs from Foz do Iguaçu-PR.


Subject(s)
Zika Virus Infection , Zika Virus , Animals , Antibodies, Viral , Brazil , Enzyme-Linked Immunosorbent Assay , Primates , Zika Virus/genetics
12.
Microb Pathog ; 172: 105763, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36116606

ABSTRACT

Studies related to the prevalence of leptospirosis in the semiarid region showed that even during long periods of drought, the disease has a remarkable frequency in herds in the region. It is a neglected disease and the extent of its effects in the Brazilian semiarid region is not known. The dynamics of this agent is well studied in the urinary tract, however, there are not many studies regarding the genital tract in female goats. Observing this scenario, the present work aimed to diagnose Leptospira spp. in female goats kept in the Brazilian semiarid region by means of serological, molecular and isolation techniques. Blood samples, vaginal fluid, urine and fragments of organs from the genitourinary tract were collected from 40 goats destined for slaughter. Microscopic agglutination test (MAT) was used as a serological technique, with a battery of 24 serovars. The Polymerase Chain Reaction (PCR) of the vaginal fluid, urine and organ fragments was performed, as well as the bacterial growth of these same products in a selective medium. Isolation positive samples were subjected to PCR. It was observed that two (5%) animals were serologically positive for the Pyrogenes serogroup. A total of 29 (72.5%) animals were PCR positive, with DNA present in 51/160 (31.8%) samples from the genital tract and 34/120 (28.3%) from the urinary tract, with no statistical difference. For bacterial growth, 22/40 (55%) animals were positive for growth, with morphology being observed in 19/160 (11.8%) for the genital tract and 16/120 (13.3%) for the urinary tract, with no statistical difference. Two uterus samples showed 99% similarity with L. interrogans after sequencing. Thus, female goats kept under semiarid conditions were positive for Leptospira spp, with positive samples from both the urinary and genital tracts, which possible is an alternative way of adapting and maintaining the agent for severe and adverse conditions.


Subject(s)
Leptospira , Leptospirosis , Urinary Tract , Animals , Female , Brazil/epidemiology , Goats , Leptospirosis/diagnosis , Leptospirosis/epidemiology , Leptospirosis/veterinary , Serogroup
13.
Pathogens ; 11(5)2022 May 12.
Article in English | MEDLINE | ID: mdl-35631091

ABSTRACT

The aim of the current study is to present a low-cost and easy-to-interpret colorimetric kit used to diagnose porcine circovirus 2 (PCV-2) to the naked eye, without any specific equipment. The aforementioned kit used as base hybrid nanoparticles resulting from the merge of surface active maghemite nanoparticles and gold nanoparticles, based on the deposition of specific PCV-2 antibodies on their surface through covalent bonds. In total, 10 negative and 40 positive samples (≥102 DNA copies/µL of serum) confirmed by qPCR technique were tested. PCV-1 virus, adenovirus, and parvovirus samples were tested as interferents to rule out likely false-positive results. Positive samples showed purple color when they were added to the complex, whereas negative samples showed red color; they were visible to the naked eye. The entire color-change process took place approximately 1 min after the analyzed samples were added to the complex. They were tested at different dilutions, namely pure, 1:10, 1:100, 1:1000, and 1:10,000. Localized surface plasmon resonance (LSPR) and transmission electron microscopy (TEM) images were generated to validate the experiment. This new real-time PCV-2 diagnostic methodology emerged as simple and economic alternative to traditional tests since the final price of the kit is USD 4.00.

14.
Viruses ; 14(3)2022 03 20.
Article in English | MEDLINE | ID: mdl-35337051

ABSTRACT

The Brazilian Society of Virology has been organizing annual meetings for 32 years now. The 32nd annual meeting, which occurred in 2021, was once again an online meeting in consequence of the issues imposed by COVID-19, even with the vaccination advances. As in the 2020 meeting, the number of attendees was high, with considerable participation by undergraduate, graduate, and postdoc students. Distinguished scientists from different countries offered high-quality conferences, and oral presentation sessions were presented by young scientists showing their newest research results. For almost five hours a day during five days, attendees discussed high-quality science related to all areas of virology. Even with the difficulties imposed by another pandemic year, the 32nd SBV annual meeting achieved its most important goal-to inspire young scientists and discuss high-quality virology research.


Subject(s)
COVID-19 , Brazil/epidemiology , Humans
15.
Transbound Emerg Dis ; 69(2): 908-912, 2022 Mar.
Article in English | MEDLINE | ID: mdl-33605554

ABSTRACT

Haemotropic mycoplasmas (haemoplasmas) are small pleomorphic bacteria infecting erythrocytes of several mammalian species, including human beings. No study to date has focused on the risk of bacteria exposure in hunting activities, particularly in natural environments of highly tick-infested areas. Accordingly, the present study aimed to assess haemoplasma occurrence in the complex encompassing wild boars, hunting dogs and hunters of Brazil. A total of 38/65 (58.5%) wild boars and 94/159 (59.1%) dogs were positive by qPCR for at least one haemoplasma. All 25 hunters were negative. Dogs with high hunting frequency were 2.4 more likely to be infected. Sequencing revealed a probable novel haemoplasma species in wild boars. Although exposure to haemoplasma species was present, the study herein found no evidence of cross-species transmission.


Subject(s)
Dog Diseases , Mycoplasma Infections , Mycoplasma , Swine Diseases , Animals , Brazil/epidemiology , Dog Diseases/epidemiology , Dog Diseases/microbiology , Dogs , Hunting , Mycoplasma Infections/epidemiology , Mycoplasma Infections/microbiology , Mycoplasma Infections/veterinary , Sus scrofa/microbiology , Swine , Swine Diseases/epidemiology
16.
Mem. Inst. Oswaldo Cruz ; 117: e220012, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1406001

ABSTRACT

BACKGROUND Zika virus (ZIKV) was discovered in 1947 with the virus isolation from Rhesus monkey (Macaca mulatta) in Uganda forest, Africa. Old World Primates are involved in a sylvatic cycle of maintenance of this arbovirus, however a limited knowledge about the role of New World primates in ZIKV transmission cycles has been established. OBJECTIVE This work aimed to investigate the presence of enzootic circulation of ZIKV in New World Primates from three Brazilian states: São Paulo, Paraíba, and Paraná. METHODS We analyzed 100 non-human primate samples collected in 2018 and 2020 from free-ranging and captive environments from São Paulo (six municipalities belonging to Sorocaba region), Paraíba (João Pessoa municipality), and Paraná (Foz do Iguaçu municipality) using reverse transcriptase quantitative polymerase reaction (RT-qPCR) assays, indirect enzyme-linked immunosorbent assay (ELISA), and plaque reduction neutralization test (PRNT). FINDINGS All samples (n = 141) tested negative for the presence of ZIKV genome from tissue and blood samples. In addition, all sera (n = 58) from Foz do Iguaçu' non-human primates (NHPs) were negative in serological assays. MAIN CONCLUSION No evidence of ZIKV circulation (molecular and serological) was found in neotropical primates. In addition, the absence of antibodies against ZIKV suggests the absence of previous viral exposure of NHPs from Foz do Iguaçu-PR.

17.
Rev Bras Parasitol Vet ; 30(4): e015021, 2021.
Article in English | MEDLINE | ID: mdl-34910019

ABSTRACT

Visceral leishmaniasis is a parasitic zoonosis that mainly affects poorest and most vulnerable populations, and domestic dogs are considered to be the main source of infection to the vector and therefore humans. However, several studies have investigated the role of other vertebrate hosts in the disease cycle. In this context, the aim of the present study was to conduct a survey of Leishmania infantum infection in donkeys and mules living in a semiarid region of Brazil. Whole blood sampled from 72 equids (65 donkeys and 7 mules) was used to perform molecular diagnosis using the real-time polymerase chain reaction (qPCR) technique. A total of 25% of the samples (18/72) were positive through qPCR, but there were no significant differences between the species (donkeys or mules), sex (male or female) and abandonment situation of the animals (yes or no). Donkeys and mules living under semiarid conditions have high frequency of L. infantum infection. It is therefore worth assigning importance to these species in the epidemiological cycle of visceral leishmaniasis, either as potential reservoirs or just as an abundant food source for vectors.


Subject(s)
Dog Diseases , Leishmania infantum , Leishmaniasis, Visceral , Leishmaniasis , Animals , Brazil/epidemiology , Dogs , Equidae , Female , Leishmania infantum/genetics , Leishmaniasis/veterinary , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/veterinary , Male
18.
Anal Methods ; 13(29): 3297-3306, 2021 07 29.
Article in English | MEDLINE | ID: mdl-34231576

ABSTRACT

Researchers worldwide have been studying alternatives to detect SARS-CoV-2 (COVID-19), and accurate and timely diagnosis is crucial for controlling the outbreaks of the disease. Surface plasmon resonance (SPR) is an effective strategy based on antibodies, and it can be used for simple and fast detection of antibodies due to COVID-19 infection. Accordingly, this paper reports on the highly sensitive and specific detection of antibody responses to SARS-CoV-2 spike (S) and nucleocapsid (N) proteins in COVID-19 patients. In this methodology, spike (S) and nucleocapsid (N) proteins belonging to the coronavirus genome were immobilized on the surface of a gold sensor using self-assembled monolayers. Previously, serum from COVID-19 patients was screened by immunochromatography-based COVID-19 IgG rapid test and/or ELISA in house to determine the presence of IgG titers. Serum from COVID-19-positive patients presenting with IgG were added on the surface and, at the time they bound to proteins, they caused refractive changes in the SPR angle. The antibody detection limit was determined through successive injections into the SPR apparatus - these injections ranged from pure (without dilution) to 1 : 200 µL. The system has shown good reproducibility between runs after coated surface regeneration with 0.1 M glycine-HCl solution (pH 3.0); all experiments were tested in triplicate. The antibodies targeted both S and N fragments and gave a high assay sensitivity by identifying 19 out of 20 COVID-19-positive patients. Most importantly, the assay time took less than 10 min. The results of this study indicate that the proposed simple strategy demonstrates high sensitivity and time-saving in the detection of SARS-CoV-2 response antibodies.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Viral , Humans , Reproducibility of Results , Surface Plasmon Resonance
19.
Viruses ; 13(3)2021 03 05.
Article in English | MEDLINE | ID: mdl-33807596

ABSTRACT

The year 2020 was profoundly marked by the emergence and spread of SARS-CoV-2, causing COVID-19, which represents the greatest pandemic of the 21st century until now, and a major challenge for virologists in the scientific and medical communities. Increased numbers of SARS-CoV-2 infection all over the world imposed social and travel restrictions, including avoidance of face-to-face scientific meetings. Therefore, for the first time in history, the 2020 edition of the Brazilian Society of Virology (SBV) congress was totally online. Despite the challenge of the new format, the Brazilian society board and collaborators were successful in virtually congregating more than 921 attendees, which was the greatest SBV participant number ever reached. Seminal talks from prominent national and international researchers were presented every night, during a week, and included discussions about environmental, basic, animal, human, plant and invertebrate virology. A special roundtable debated exclusively new data and perspectives regarding COVID-19 by some of the greatest Brazilian virologists. Women scientists were very well represented in another special roundtable called "Young Women Inspiring Research", which was one of the most viewed and commented section during the meeting, given the extraordinary quality of the presented work. Finally, SBV offered the Helio Gelli Pereira award for one graduate and one undergraduate student, which has also been a fruitful collaboration between the society and Viruses journal. The annual SBV meeting has, therefore, reached its goals to inspire young scientists, stimulate high-quality scientific discussion and to encourage global collaboration between virologists.


Subject(s)
Virology , Brazil , Group Processes , Humans , Societies, Scientific , User-Computer Interface , Virology/organization & administration
20.
Microb Drug Resist ; 27(4): 562-570, 2021 Apr.
Article in English | MEDLINE | ID: mdl-32865485

ABSTRACT

Salmonella spp. is a foodborne pathogen present in the pork production chain, leading to potential contamination of end products and causing salmonellosis cases and outbreaks worldwide. The emergence of multidrug-resistant (MDR) Salmonella spp., especially isolates obtained from animal origin food, is a global concern. This study aimed to isolate Salmonella from swine mesenteric lymph nodes (MLN) and to characterize the virulence and antibiotic resistance profiles. MLN samples were obtained from a swine slaughterhouse and subjected to Salmonella spp. isolation. Ten MLN samples were positive and 29 isolates were identified based on PCR (invA and ompC) and serotyping: Derby, Cerro, and Give. Pulsed-field gel electrophoresis allowed to group the isolates based on their serotypes, resulting in three major clusters. All isolates presented the virulence-related genes pefA, sipA, sopB, spaN, and pagC. Relatively high numbers of Salmonella spp. were resistant to neomycin, polymyxin B, ciprofloxacin, tetracycline, and nalidixic acid. Furthermore, 25 isolates presented simultaneous resistance to three or more antibiotic classes, being characterized as MDR. The obtained results confirmed the relevance of swine as reservoirs of Salmonella spp. in the pork production chain and demonstrated the MDR profiles of isolates. Proper control and surveillance are required to avoid the contamination of end products.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/genetics , Salmonella/drug effects , Swine/microbiology , Animals , Brazil , Lymph Nodes/microbiology , Microbial Sensitivity Tests , Virulence
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