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1.
Vox Sang ; 119(3): 257-264, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38223953

RESUMO

BACKGROUND AND OBJECTIVES: Serological HTLV-1/2 screening is mandatory for blood donor candidates in Brazil. Our objective was to analyse HTLV test results in blood donors submitted for screening and confirmatory assays in a Brazilian blood bank. MATERIALS AND METHODS: Retrospective analysis (2017-2022) results of chemiluminescence immunoassays and confirmatory tests for HTLV-1/2 in reactive donors were performed. During the analysed period, three sets of assays were used: (1) Architect rHTLV-I/II + HTLV Blot 2.4 (Western blot [WB]); (2) Alinity s HTLV I/II Reagent Kit + INNO-line immunoassay (LIA) HTLV I/II Score (LIA); (3) Alinity + WB. RESULTS: The analysed period comprised a total of 1,557,333 donations. The mean percentage of HTLV reactive donors using the Architect assay was 0.14%. With the change to the Alinity assay, that percentage dropped 2.3-fold (0.06%). The reactivity rate in the confirmatory tests (1064 samples) ranged from 13.5% to 30.2%, whereas 58.3%-85.9% of samples were non-reactive. The highest rates of positive (30.2%) and indeterminate (11.5%) results were seen using LIA. Considering all analysed samples, those with signal/cut-off ratio (S/CO) >50 were positive in confirmatory tests (positive predictive value, PPV = 100%), whereas samples with S/CO ≤6 are very unlikely to be truly positive (PPV = 0). CONCLUSION: The use of the Alinity assay reduced the frequency of false-positive results. Confirmatory tests are important to identify true HTLV infection in blood donors, because more than 58% of initially reactive individuals are confirmed as seronegative. Categorizing S/CO values is useful for assessing the likelihood of true HTLV-1/2 infection.


Assuntos
Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Doadores de Sangue , Estudos Retrospectivos , Vírus Linfotrópico T Tipo 2 Humano , Western Blotting , Linfócitos T
2.
Virus Res ; 340: 199291, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38065303

RESUMO

Here, the antiviral activity of aminoadamantane derivatives were evaluated against SARS-CoV-2. The compounds exhibited low cytotoxicity to Vero, HEK293 and CALU-3 cells up to a concentration of 1,000 µM. The inhibitory concentration (IC50) of aminoadamantane was 39.71 µM in Vero CCL-81 cells and the derivatives showed significantly lower IC50 values, especially for compounds 3F4 (0.32 µM), 3F5 (0.44 µM) and 3E10 (1.28 µM). Additionally, derivatives 3F5 and 3E10 statistically reduced the fluorescence intensity of SARS-CoV-2 protein S from Vero cells at 10 µM. Transmission microscopy confirmed the antiviral activity of the compounds, which reduced cytopathic effects induced by the virus, such as vacuolization, cytoplasmic projections, and the presence of myelin figures derived from cellular activation in the face of infection. Additionally, it was possible to observe a reduction of viral particles adhered to the cell membrane and inside several viral factories, especially after treatment with 3F4. Moreover, although docking analysis showed favorable interactions in the catalytic site of Cathepsin L, the enzymatic activity of this enzyme was not inhibited significantly in vitro. The new derivatives displayed lower predicted toxicities than aminoadamantane, which was observed for either rat or mouse models. Lastly, in vivo antiviral assays of aminoadamantane derivatives in BALB/cJ mice after challenge with the mouse-adapted strain of SARS-CoV-2, corroborated the robust antiviral activity of 3F4 derivative, which was higher than aminoadamantane and its other derivatives. Therefore, aminoadamantane derivatives show potential broad-spectrum antiviral activity, which may contribute to COVID-19 treatment in the face of emerging and re-emerging SARS-CoV-2 variants of concern.


Assuntos
COVID-19 , SARS-CoV-2 , Chlorocebus aethiops , Humanos , Animais , Camundongos , Ratos , Tratamento Farmacológico da COVID-19 , Células HEK293 , Células Vero , Amantadina , Antivirais/farmacologia , Antivirais/uso terapêutico
3.
Front Immunol ; 14: 1229712, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022506

RESUMO

Introduction and methods: In this present work, coronavirus subfamilies and SARS-CoV-2 Variants of Concern (VOCs) were investigated for the presence of MHC-I immunodominant viral peptides using in silico and in vitro tools. Results: In our results, HLA-A*02 haplotype showed the highest number of immunodominant epitopes but with the lowest combined prediction score. Furthermore, a decrease in combined prediction score was observed for HLA-A*02-restricted epitopes when the original strain was compared to the VOCs, indicating that the mutations on the VOCs are promoting escape from HLA-A2-mediated antigen presentation, which characterizes a immune evasion process. Additionally, epitope signature analysis revealed major immunogenic peptide loss for structural (S) and non-structural (ORF8) proteins of VOCs in comparison to the Wuhan sequence. Discussion: These results may indicate that the antiviral CD8+ T-cell responses generated by original strains could not be sufficient for clearance of variants in either newly or reinfection with SARS-CoV-2. In contrast, N epitopes remain the most conserved and reactive peptides across SARS-CoV-2 VOCs. Overall, our data could contribute to the rational design and development of new vaccinal platforms to induce a broad cellular CD8+ T cell antiviral response, aiming at controlling viral transmission of future SARS-CoV-2 variants.


Assuntos
Linfócitos T CD8-Positivos , COVID-19 , Humanos , SARS-CoV-2 , Epitopos de Linfócito T/genética , Antígenos de Histocompatibilidade Classe I , Antígeno HLA-A2 , Peptídeos , Antivirais
4.
Virol J ; 20(1): 145, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37434252

RESUMO

BACKGROUND: Cell responses to different stress inducers are efficient mechanisms that prevent and fight the accumulation of harmful macromolecules in the cells and also reinforce the defenses of the host against pathogens. Vaccinia virus (VACV) is an enveloped, DNA virus, belonging to the Poxviridae family. Members of this family have evolved numerous strategies to manipulate host responses to stress controlling cell survival and enhancing their replicative success. In this study, we investigated the activation of the response signaling to malformed proteins (UPR) by the VACV virulent strain-Western Reserve (WR)-or the non-virulent strain-Modified Vaccinia Ankara (MVA). METHODS: Through RT-PCR RFLP and qPCR assays, we detected negative regulation of XBP1 mRNA processing in VACV-infected cells. On the other hand, through assays of reporter genes for the ATF6 component, we observed its translocation to the nucleus of infected cells and a robust increase in its transcriptional activity, which seems to be important for virus replication. WR strain single-cycle viral multiplication curves in ATF6α-knockout MEFs showed reduced viral yield. RESULTS: We observed that VACV WR and MVA strains modulate the UPR pathway, triggering the expression of endoplasmic reticulum chaperones through ATF6α signaling while preventing IRE1α-XBP1 activation. CONCLUSIONS: The ATF6α sensor is robustly activated during infection while the IRE1α-XBP1 branch is down-regulated.


Assuntos
Fatores de Transcrição , Vaccinia virus , Fatores de Transcrição/genética , Vaccinia virus/genética , Endorribonucleases , Proteínas Serina-Treonina Quinases , Estresse do Retículo Endoplasmático , Resposta a Proteínas não Dobradas
5.
Biomolecules ; 13(3)2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36979478

RESUMO

The present study sought to search for the immunodominance related to the N-terminal, Central and C-terminal regions of HTLV-1 Tax using novel, cutting-edge peptide microarray analysis. In addition, in silico predictions were performed to verify the presence of nine amino acid peptides present along Tax restricted to the human leukocyte antigen (HLA)-A2.02*01 haplotype, as well as to verify the ability to induce pro-inflammatory and regulatory cytokines, such as IFN-γ and IL-4, respectively. Our results indicated abundant dose-dependent reactivity for HLA-A*02:01 in all regions (N-terminal, Central and C-terminal), but with specific hotspots. Furthermore, the results of fold-change over the Tax11-19 reactivity obtained at lower concentrations of HLA-A*02:01 reveal that peptides from the three regions contain sequences that react 100 times more than Tax11-19. On the other hand, Tax11-19 has similar or superior HLA-A*02:01 reactivity at higher concentrations of this haplotype. The in silico analysis showed a higher frequency of IFN-γ-inducing peptides in the N-terminal portion, while the C-terminal portion showed a higher frequency of IL-4 inducers. Taken together, these results shed light on the search for new Tax immunodominant epitopes, in addition to the canonic Tax11-19, for the rational design of immunomodulatory strategies for HTLV-1 chronic diseases.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Humanos , Vírus Linfotrópico T Tipo 1 Humano/genética , Antígeno HLA-A2 , Epitopos Imunodominantes , Produtos do Gene tax/genética , Linfócitos T Citotóxicos , Interleucina-4 , Peptídeos
6.
Front Immunol ; 13: 1035515, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466864

RESUMO

Introduction: The present work sought to identify MHC-I-restricted peptide signatures for arbovirus using in silico and in vitro peptide microarray tools. Methods: First, an in-silico analysis of immunogenic epitopes restricted to four of the most prevalent human MHC class-I was performed by identification of MHC affinity score. For that, more than 10,000 peptide sequences from 5 Arbovirus and 8 different viral serotypes, namely Zika (ZIKV), Dengue (DENV serotypes 1-4), Chikungunya (CHIKV), Mayaro (MAYV) and Oropouche (OROV) viruses, in addition to YFV were analyzed. Haplotype HLA-A*02.01 was the dominant human MHC for all arboviruses. Over one thousand HLA-A2 immunogenic peptides were employed to build a comprehensive identity matrix. Intending to assess HLAA*02:01 reactivity of peptides in vitro, a peptide microarray was designed and generated using a dimeric protein containing HLA-A*02:01. Results: The comprehensive identity matrix allowed the identification of only three overlapping peptides between two or more flavivirus sequences, suggesting poor overlapping of virus-specific immunogenic peptides amongst arborviruses. Global analysis of the fluorescence intensity for peptide-HLA-A*02:01 binding indicated a dose-dependent effect in the array. Considering all assessed arboviruses, the number of DENV-derived peptides with HLA-A*02:01 reactivity was the highest. Furthermore, a lower number of YFV-17DD overlapping peptides presented reactivity when compared to non-overlapping peptides. In addition, the assessment of HLA-A*02:01-reactive peptides across virus polyproteins highlighted non-structural proteins as "hot-spots". Data analysis supported these findings showing the presence of major hydrophobic sites in the final segment of non-structural protein 1 throughout 2a (Ns2a) and in nonstructural proteins 2b (Ns2b), 4a (Ns4a) and 4b (Ns4b). Discussion: To our knowledge, these results provide the most comprehensive and detailed snapshot of the immunodominant peptide signature for arbovirus with MHC-class I restriction, which may bring insight into the design of future virus-specific vaccines to arboviruses and for vaccination protocols in highly endemic areas.


Assuntos
Arbovírus , Infecção por Zika virus , Zika virus , Humanos , Epitopos , Antígeno HLA-A2 , Antígenos Virais
7.
Vaccines (Basel) ; 10(10)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36298582

RESUMO

The feline immunodeficiency virus (FIV) is a retrovirus with global impact and distribution, affecting both domestic and wild cats. This virus can cause severe and progressive immunosuppression culminating in the death of felids. Since the discovery of FIV, only one vaccine has been commercially available. This vaccine has proven efficiency against FIV subtypes A and D, whereas subtype B (FIV-B), found in multiple continents, is not currently preventable by vaccination. We, therefore, developed and evaluated a vaccine prototype against FIV-B using the recombinant viral vector modified vaccinia virus Ankara (MVA) expressing the variable region V1-V3 of the FIV-B envelope protein. We conducted preclinical tests in immunized mice (C57BL/6) using a prime-boost protocol with a 21 day interval and evaluated cellular and humoral responses as well the vaccine viability after lyophilization and storage. The animals immunized with the recombinant MVA/FIV virus developed specific splenocyte proliferation when stimulated with designed peptides. We also detected cellular and humoral immunity activation with IFN-y and antibody production. The data obtained in this study support further development of this immunogen and testing in cats.

8.
Rev Soc Bras Med Trop ; 55: e02392022, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36287506

RESUMO

BACKGROUND: The inflammatory response plays a significant role in the outcome of coronavirus disease (COVID-19). METHODS: We investigated plasma cytokine and chemokine concentrations in non-infected (NI), asymptomatic severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2)-infected blood donors (AS), and patients with severe COVID-19 (SC). RESULTS: The SC group showed significantly higher levels of interleukin 6 (IL-6), IL-10, and CCL5 than the AS and NI groups. The SC and AS groups had considerably greater CXCL9 and CXCL10 concentrations than the NI group. Only NI and infected people showed separate clusters in the principal component analysis. CONCLUSIONS: SC, as well as AS was characterized by an inflammatory profile.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Interleucina-10 , Interleucina-6 , Doadores de Sangue , Quimiocinas , Citocinas
9.
Vox Sang ; 117(9): 1090-1097, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35768998

RESUMO

BACKGROUND AND OBJECTIVES: Transfusion-transmitted viruses count among the greatest threats to blood safety. In Argentina, current laws oblige testing all donated blood for the presence of antibodies against human T-cell lymphotropic viruses 1 and 2 (HTLV-1/2). In endemic zones of the country, a high rate of seronegative HTLV-1 individuals with clear evidence of infection because of symptoms and/or presence of tax sequences of HTLV-1 and/or IgG anti-Tax antibodies has been recently described. Migration from endemic to nonendemic zones of Argentina is very frequent. MATERIALS AND METHODS: During a 1-year period, in the blood bank of Córdoba city, we performed molecular screening of all donors who were born in or arose from endemic zones for HTLV-1/2 in Argentina and neighbouring countries. RESULTS: By screening 219 bp of HTLV-1/2 tax gene, 0.6% (2/317) of the blood donors proved to be positive for HTLV-1 tax sequence. One of the donors presented anti-Tax antibodies, demonstrating the transcriptional activity of the tax gene, and the other donor was also positive for LTR and pol gene sequences. The HTLV-1 genetic analysis of the LTR sequence determined that it belonged to the Cosmopolitan subtype HTLV-1aA. CONCLUSION: These findings suggest potential limitations of some currently approved screening assays for HTLV-1 detection applied in some donor populations and the possibility of an HTLV-1 seronegative carrier state with the potential for silent transmission by blood.


Assuntos
Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Bancos de Sangue , Infecções por HTLV-I/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/genética , Humanos , Linfócitos T
10.
Front Public Health ; 10: 884701, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677763

RESUMO

A multi-epitope protein expressed in a prokaryotic system, including epitopes of Env, Gag, and Tax proteins of both HTLV-1 and HTLV-2 was characterized for HTLV-1/2 serological screening. This tool can contribute to support the implementation of public policies to reduce HTLV-1/2 transmission in Brazil, the country with the highest absolute numbers of HTLV-1/2 infected individuals. The chimeric protein was tested in EIA using serum/plasma of HTLV-infected individuals and non-infected ones from four Brazilian states, including the North and Northeast regions (that present high prevalence of HTLV-1/2) and Southeast region (that presents intermediate prevalence rates) depicting different epidemiological context of HTLV-1/2 infection in our country. We enrolled samples from Pará (n = 114), Maranhão (n = 153), Minas Gerais (n = 225) and São Paulo (n = 59) states; they are from blood donors' candidates (Pará and Minas Gerais), pregnant women (Maranhão) and HIV+/high risk for sexually transmitted infection (STI; São Paulo). Among the HTLV-1/2 positive sera, there were co-infections with viral (HTLV-1 + HTLV-2, HIV, HCV, and HBV), bacterial (Treponema pallidum) and parasitic (Trypanosoma cruzi, Schistosma mansoni, Strongyloides stercoralis, Entamoeba coli, E. histolytica, and Endolimax nana) pathogens related to HTLV-1/2 co-morbidities that can contribute to inconclusive diagnostic results. Sera positive for HIV were included among the HTLV-1/2 negative samples. Considering both HTLV-1 and HTLV-2-infected samples from all states and different groups (blood donor candidates, pregnant women, and individuals with high risk for STI), mono or co-infected and HTLV-/HIV+, the test specificity ranged from 90.09 to 95.19% and the sensitivity from 82.41 to 92.36% with high accuracy (ROC AUC = 0.9552). This multi-epitope protein showed great potential to be used in serological screening of HTLV-1 and HTLV-2 in different platforms, even taking into account the great regional variation and different profile of HTLV-1 and HTLV-2 mono or co-infected individuals.


Assuntos
Infecções por HIV , Infecções por HTLV-I , Infecções por HTLV-II , Vírus Linfotrópico T Tipo 1 Humano , Infecções Sexualmente Transmissíveis , Brasil/epidemiologia , Epitopos , Feminino , Infecções por HIV/diagnóstico , Infecções por HTLV-I/diagnóstico , Infecções por HTLV-I/epidemiologia , Infecções por HTLV-II/diagnóstico , Infecções por HTLV-II/epidemiologia , Vírus Linfotrópico T Tipo 2 Humano , Humanos , Gravidez , Infecções Sexualmente Transmissíveis/epidemiologia
11.
Frontiers in Public Health ; 10: 1-12, 23 May 2022. tab, graf, ilus
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-ACVSES, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-1400813

RESUMO

A multi-epitope protein expressed in a prokaryotic system, including epitopes of Env, Gag, and Tax proteins of both HTLV-1 and HTLV-2 was characterized for HTLV-1/2 serological screening. This tool can contribute to support the implementation of public policies to reduce HTLV-1/2 transmission in Brazil, the country with the highest absolute numbers of HTLV-1/2 infected individuals. The chimeric protein was tested in EIA using serum/plasma of HTLV-infected individuals and non-infected ones from four Brazilian states, including the North and Northeast regions (that present high prevalence of HTLV-1/2) and Southeast region (that presents intermediate prevalence rates) depicting different epidemiological context of HTLV-1/2 infection in our country. We enrolled samples from Pará (n = 114), Maranhão (n = 153), Minas Gerais (n = 225) and São Paulo (n = 59) states; they are from blood donors' candidates (Pará and Minas Gerais), pregnant women (Maranhão) and HIV+/high risk for sexually transmitted infection (STI; São Paulo). Among the HTLV-1/2 positive sera, there were co-infections with viral (HTLV-1 + HTLV-2, HIV, HCV, and HBV), bacterial (Treponema pallidum) and parasitic (Trypanosoma cruzi, Schistosma mansoni, Strongyloides stercoralis, Entamoeba coli, E. histolytica, and Endolimax nana) pathogens related to HTLV-1/2 co-morbidities that can contribute to inconclusive diagnostic results. Sera positive for HIV were included among the HTLV-1/2 negative samples. Considering both HTLV-1 and HTLV-2-infected samples from all states and different groups (blood donor candidates, pregnant women, and individuals with high risk for STI), mono or co-infected and HTLV-/HIV+, the test specificity ranged from 90.09 to 95.19% and the sensitivity from 82.41 to 92.36% with high accuracy (ROC AUC = 0.9552). Thismulti-epitope protein showed great potential to be used in serological screening of HTLV-1 and HTLV-2 in different platforms, even taking into account the great regional variation and different profile of HTLV-1 and HTLV-2 mono or co-infected individuals. (AU)


Assuntos
Testes Sorológicos , Vírus Linfotrópico T Tipo 1 Humano , Vírus Linfotrópico T Tipo 2 Humano , Coinfecção , Epitopos
12.
Appl Environ Microbiol ; 88(9): e0004422, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35416681

RESUMO

Klebsiella variicola, a member of Klebsiella pneumoniae complex, is found to infect plants, insects, and animals and is considered an emerging pathogen in humans. While antibiotic resistance is often prevalent among K. variicola isolates from humans, this has not been thoroughly investigated in isolates from nonhuman sources. Prior evidence suggests that K. variicola can be transmitted between agricultural products as well as between animals, and the use of antibiotics in agriculture has increased antibiotic resistance in other emerging pathogens. Furthermore, in animals that contain K. variicola as a normal member of the rumen microbiota, the same bacteria can also cause infections, such as clinical mastitis in dairy cows. Here, we describe K. variicola UFMG-H9 and UFMG-H10, both isolated from the urine of healthy Gyr heifers. These two genomes represent the first isolates from the urine of cattle and exhibit greater similarity with strains from the human urinary tract than isolates from bovine fecal or milk samples. Unique to the UFMG-H9 genome is the presence of flagellar genes, the first such observation for K. variicola. Neither of the sampled animals had symptoms associated with K. variicola infection, even though genes associated with virulence and antibiotic resistance were identified in both strains. Both strains were resistant to amoxicillin, erythromycin, and vancomycin, and UFMG-H10 is resistant to fosfomycin. The observed resistances emphasize the concern regarding the emergence of this species as a human pathogen given its circulation in healthy livestock animals. IMPORTANCE Klebsiella variicola is an opportunistic pathogen in humans. It also has been associated with bovine mastitis, which can have significant economic effects. While numerous isolates have been sequenced from human infections, only 12 have been sequenced from cattle (fecal and milk samples) to date. Recently, we discovered the presence of K. variicola in the urine of two healthy heifers, the first identification of K. variicola in the bovine urinary tract and the first confirmed K. variicola isolate encoding for flagella-mediated motility. Here, we present the genome sequences and analysis of these isolates. The bovine urinary genomes are more similar to isolates from the human urinary tract than they are to other isolates from cattle, suggesting niche specialization. The presence of antibiotic resistance genes is concerning, as prior studies have found transmission between animals. These findings are important to understand the circulation of K. variicola in healthy livestock animals.


Assuntos
Infecções por Klebsiella , Animais , Antibacterianos/farmacologia , Bovinos , Farmacorresistência Bacteriana Múltipla/genética , Feminino , Humanos , Klebsiella/genética , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/veterinária , Klebsiella pneumoniae/genética , Filogenia
13.
Front Microbiol ; 13: 764760, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35330764

RESUMO

The study of livestock microbiota has immediate benefits for animal health as well as mitigating food contamination and emerging pathogens. While prior research has indicated the gastrointestinal tract of cattle as the source for many zoonoses, including Shiga-toxin producing Escherichia coli and antibiotic resistant bacteria, the bovine urinary tract microbiota has yet to be thoroughly investigated. Here, we describe 5 E. coli and 4 Pseudomonas aeruginosa strains isolated from urine of dairy Gyr cattle. While both species are typically associated with urinary tract infections and mastitis, all of the animals sampled were healthy. The bovine urinary strains were compared to E. coli and P. aeruginosa isolates from other bovine samples as well as human urinary samples. While the bovine urinary E. coli isolates had genomic similarity to isolates from the gastrointestinal tract of cattle and other agricultural animals, the bovine urinary P. aeruginosa strains were most similar to human isolates suggesting niche adaptation rather than host adaptation. Examination of prophages harbored by these bovine isolates revealed similarity with prophages within distantly related E. coli and P. aeruginosa isolates from the human urinary tract. This suggests that related urinary phages may persist and/or be shared between mammals. Future studies of the bovine urinary microbiota are needed to ascertain if E. coli and P. aeruginosa are resident members of this niche and/or possible sources for emerging pathogens in humans.

14.
Emerg Infect Dis ; 28(4): 734-742, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35180375

RESUMO

During epidemics, data from different sources can provide information on varying aspects of the epidemic process. Serology-based epidemiologic surveys could be used to compose a consistent epidemic scenario. We assessed the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG in serum samples collected from 7,837 blood donors in 7 cities of Brazil during March-December 2020. Based on our results, we propose a modification in a compartmental model that uses reported number of SARS-CoV-2 cases and serology results from blood donors as inputs and delivers estimates of hidden variables, such as daily values of SARS-CoV-2 transmission rates and cumulative incidence rate of reported and unreported SARS-CoV-2 cases. We concluded that the information about cumulative incidence of a disease in a city's population can be obtained by testing serum samples collected from blood donors. Our proposed method also can be extended to surveillance of other infectious diseases.


Assuntos
COVID-19 , Epidemias , Anticorpos Antivirais , Doadores de Sangue , Brasil/epidemiologia , COVID-19/epidemiologia , Humanos , Imunoglobulina G , SARS-CoV-2 , Estudos Soroepidemiológicos
15.
J Med Virol ; 94(2): 683-691, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34738645

RESUMO

Prevalence of hepatitis C virus (HCV) is high in hemophilia A patients and the development of FVIII inhibitor is another challenge in the management of these individuals. The influence of HCV infection in the occurrence of inhibitors was investigated by the comparison of clinical and laboratory data from noninfected (NI, n = 96) and chronically HCV-infected (HCV, n = 58) hemophilia A patients. Concentrations of plasmatic cytokines (IL-2, IL-4, IL-6, IL-10, TNF, IFN-γ, and IL-17A) and chemokines (CCL2, CCL5, CXCL8, CXCL9, and CXCL10) were quantified from patients' samples. The results showed that older age, use of cryoprecipitate and fresh frozen plasma, and severe hemophilia were associated with HCV infection, whereas exclusive use of virus inactivated clotting factors was a protector factor to acquiring HCV infection. HCV infection was strongly associated with low levels of inhibitor (OR = 20.53, p < 0.001). Patients with a history of inhibitor (INB+) presented a mixed immune profile characterized by higher levels of pro-and anti-inflammatory cytokines than those without a history of inhibitor (INB-). The highest levels of CCL2 and CXCL8 were seen in HCVINB- , whereas CXCL9 and CXCL10 in HCVINB+ . Heatmap analysis of the set of cytokines and chemokines concentration distributed HCV patients into two distinct clusters, HCVINB+ and HCVINB- , both characterized by low concentrations of IL-4, while noninfected patients were grouped in a single block regardless of inhibitor development history (NIINB-/INB+ ). This finding suggests that the strong association between HCV infection and low levels of factor VIII inhibitors might be due to the modulation of the cytokine and chemokine network established by the antiviral response.


Assuntos
Inibidores dos Fatores de Coagulação Sanguínea/uso terapêutico , Fator VIII/antagonistas & inibidores , Hemofilia A/complicações , Hepatite C Crônica/complicações , Adolescente , Adulto , Quimiocinas/metabolismo , Citocinas/metabolismo , Feminino , Hemofilia A/terapia , Hepatite C Crônica/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Plasma , Adulto Jovem
16.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;55: e0239, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1406975

RESUMO

ABSTRACT Background: The inflammatory response plays a significant role in the outcome of coronavirus disease (COVID-19). Methods: We investigated plasma cytokine and chemokine concentrations in non-infected (NI), asymptomatic severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2)-infected blood donors (AS), and patients with severe COVID-19 (SC). Results: The SC group showed significantly higher levels of interleukin 6 (IL-6), IL-10, and CCL5 than the AS and NI groups. The SC and AS groups had considerably greater CXCL9 and CXCL10 concentrations than the NI group. Only NI and infected people showed separate clusters in the principal component analysis. Conclusions: SC, as well as AS was characterized by an inflammatory profile.

17.
Microbiology (Reading) ; 167(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34269674

RESUMO

Corynebacterium phoceense is a Gram-positive species previously isolated from human urine. Although other species from the same genus have been associated with urinary tract infections, C. phoceense is currently believed to be a non-pathogenic member of the urogenital microbiota. Prior to our study, only two isolates were described in the literature, and very little is known about the species. Here, we describe C. phoceense UFMG-H7, the first strain of this species isolated from the urine of healthy cattle. The genome for this isolate was produced and compared to the two other publicly available C. phoceense as well as other Corynebacterium genome assemblies. Our in-depth genomic analysis identified four additional publicly available genome assemblies that are representatives of the species, also isolated from the human urogenital tract. Although none of the strains have been associated with symptoms or disease, numerous genes associated with virulence factors are encoded. In contrast to related Corynebacterium species and Corynebacterium species from the bovine vaginal tract, all C. phoceense strains examined code for the SpaD-type pili suggesting adherence is essential for its persistence within the urinary tract. As the other C. phoceense strains analysed were isolated from the human urogenital tract, our results suggest that this species may be specific to this niche.


Assuntos
Corynebacterium/isolamento & purificação , Microbiota , Sistema Urogenital/microbiologia , Animais , Bovinos , Corynebacterium/classificação , Corynebacterium/genética , Genoma Bacteriano , Humanos , Urina/microbiologia
18.
Rev Soc Bras Med Trop ; 54: e01752021, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105630

RESUMO

INTRODUCTION: We present a data analysis and review of recent studies regarding the laboratory diagnosis of human T-lymphotropic virus 1 and 2 (HTLV-1/2) infections in Brazil. METHODS: Target populations, available diagnostic serological assays (screening and complementary tests), molecular assays (in-house), causes of false-positive and false-negative results, and flowcharts were analyzed. RESULTS: A table presents the target populations, two diagnostic flowcharts (depending on laboratory infrastructure and study population), and recent research that may improve how HTLV-1/2 is diagnosed in Brazil. CONCLUSIONS: Our results support the implementation of public policies to reduce HTLV-1/2 transmission and its associated diseases.


Assuntos
Infecções por HTLV-I , Infecções por HTLV-II , Vírus Linfotrópico T Tipo 1 Humano , Brasil , Técnicas de Laboratório Clínico , Infecções por HTLV-I/diagnóstico , Infecções por HTLV-II/diagnóstico , Infecções por HTLV-II/epidemiologia , Vírus Linfotrópico T Tipo 2 Humano , Humanos , Design de Software
19.
Immunol Lett ; 235: 9-14, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33901540

RESUMO

An alarming disease caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) named COVID-19 has emerged as an unprecedented public health problem and ignited a world health crisis. As opposed to what was believed at the beginning of the pandemic, the virus has not only spread but persevere causing secondary waves and challenging the concept of herd immunity against viral infections. While the majority of SARS-CoV-2-infected individuals may remain asymptomatic, a fraction of individuals may develop low to high-grade severity signs and symptoms of COVID-19. The disease is multifactorial and can progress quickly, leading to severe complications and even death in a few days. Therefore, understanding the pre-existing factors for disease development has never been so pressing. In this scenario, the insights on the mechanisms underlying disease allied to the immune response developed during the viral invasion could shed light on novel predictive factors and prognostic tools for COVID-19 management and interventions. A recent genome-wide association study (GWAS) revealed several molecules that significantly impacted critically ill COVID-19 patients, leading to the core mechanisms of COVID-19 pathogenesis. Considering these findings and the fact that ACE-2 polymorphisms alone cannot explain disease progress and severity, this review aims at summarizing the most important and recent findings of the research and expert consensus of possible cytokine-related polymorphisms existing in the differential expression of paramount immune molecules that could be crucial for providing guidelines for decision-making and appropriate clinical management of COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Citocinas , Pandemias , Polimorfismo Genético , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/imunologia , COVID-19/genética , COVID-19/imunologia , COVID-19/mortalidade , Citocinas/genética , Citocinas/imunologia , Estudo de Associação Genômica Ampla , Humanos
20.
G3 (Bethesda) ; 11(1)2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33561240

RESUMO

While the gram-positive bacterium Vagococcus fluvialis has been isolated from the environment as well as fish, birds, and mammals, very little is known about the species. V. fluvialis is believed to be a probiotic in fishes. However, within mammals, it is more frequently isolated from infectious tissue, including on rare occasions human and livestock lesions. Prior to the study described here, V. fluvialis had never been found in healthy bovine animals. Here, we present the complete genomes of V. fluvialis UFMG-H6, UFMG-H6B, and UFMG-H7, novel strains isolated from urine samples from healthy bovine females. These are the first genomes of mammalian isolates and the first description of V. fluvialis from urine. The genomes did not encode for any known virulence genes, suggesting that they may be commensal members of the urine microbiota.


Assuntos
Enterococcaceae , Peixes , Animais , Bovinos , Feminino , Virulência
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