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1.
Front Vet Sci ; 11: 1397145, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39346959

RESUMEN

Introduction: Mycoplasma bovis is a highly contagious pathogen that causes various diseases in herd animals, negatively impacting reproduction, production, and milk yield. Effective diagnostic methods and vaccine development are critical for controlling M. bovis outbreaks. This systematic review aimed to evaluate diagnostic alternatives and vaccine compounds based on recombinant proteins. Methods: Following the PRISMA protocol, a systematic search was conducted in the SciELO, PubMed, and CAPES Periodicals Portal databases. Inclusion criteria included studies published between 2008 and 2023 that involved (1) the use of recombinant proteins for M. bovis identification or vaccine production, (2) biological samples, (3) availability in the selected databases, (4) in vitro or in vivo experimental designs, and (5) English-language publications. Results: Ten of the initial 53 studies screened met the inclusion criteria. Of these, four studies focused on diagnostic approaches and six on vaccine development. Diagnostic studies predominantly used an indirect enzyme-linked immunosorbent assay (ELISA) with recombinant proteins, achieving over 90% sensitivity and specificity in detecting M. bovis infections. In contrast, the development of recombinant vaccines has shown limited success, with challenges in identifying effective adjuvants and optimizing conditions for protective immunity. Discussion: While recombinant protein-based diagnostics have proven effective, developing a successful vaccine against M. bovis remains elusive. Further research is necessary to refine vaccine formulations, including selecting suitable adjuvants and challenge models to enhance protective efficacy against M. bovis infections.

2.
Microorganisms ; 10(5)2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35630474

RESUMEN

Ureaplasma diversum is a bacterial pathogen that infects cattle and can cause severe inflammation of the genital and reproductive systems. Lipid-associated membrane proteins (LAMPs), including GUDIV-103, are the main virulence factors in this bacterium. In this study, we heterologously expressed recombinant GUDIV-103 (rGUDIV-103) in Escherichia coli, purified it, and evaluated its immunological reactivity and immunomodulatory effects in bovine peripheral blood mononuclear cells (PBMCs). Samples from rabbits inoculated with purified rGUDIV-103 were analysed using indirect enzyme-linked immunosorbent assay and dot blotting to confirm polyclonal antibody production and assess kinetics, respectively. The expression of this lipoprotein in field isolates was confirmed via Western blotting with anti-rGUDIV-103 serum and hydrophobic or hydrophilic proteins from 42 U. diversum strains. Moreover, the antibodies produced against the U. diversum ATCC 49783 strain recognised rGUDIV-103. The mitogenic potential of rGUDIV-103 was evaluated using a lymphoproliferation assay in 5(6)-carboxyfluorescein diacetate succinimidyl ester−labelled bovine PBMCs, where it induced lymphocyte proliferation. Quantitative polymerase chain reaction analysis revealed that the expression of interleukin-1ß, toll-like receptor (TLR)-α, TLR2, TLR4, inducible nitric oxide synthase, and caspase-3−encoding genes increased more in rGUDIV-103−treated PBMCs than in untreated cells (p < 0.05). Treating PBMCs with rGUDIV-103 increased nitric oxide and hydrogen peroxide levels. The antigenic and immunogenic properties of rGUDIV-103 suggested its suitability for immunobiological application.

3.
Fertil Steril ; 116(4): 1030-1039, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34325918

RESUMEN

OBJECTIVE: To study the inflammatory profile and genes involved in the response to bacterial infections in women who developed spontaneous abortion in the presence of Ureaplasma parvum. DESIGN: Cross-sectional study. SETTING: A maternal and child referral center. PATIENT(S): Eighty-nine women with spontaneous abortion and 20 women with normal vaginal delivery (control group) were studied. INTERVENTION(S): Samples of biopsied placental tissue were collected for Mollicutes detection. MAIN OUTCOME MEASURE(S): The samples were subjected to histologic analysis, immunohistochemical evaluation for macrophages and lymphocytes, cytokine quantification, and quantitative polymerase chain reaction array to evaluate the expression of 84 genes related to the innate and adaptive immune responses. RESULT(S): The presence of U. parvum in the abortion group was positively associated with the influx of polymorphonuclear cells in the placental tissue and increased concentrations of interleukin-6 and interleukin-12p70. U. parvum caused downregulation of genes involved in the immune response, such as attraction of immune cells, activation of an inflammatory response, T-helper cell 17 response activation, and activation of the complement system at the beginning and end of pregnancy. CONCLUSION: The direct action of U. parvum on placental tissue altered the gestational tolerogenic state, reducing the immune response against pathogens and activating the extrinsic apoptotic pathway, causing spontaneous abortion.


Asunto(s)
Aborto Espontáneo/microbiología , Histocompatibilidad Materno-Fetal , Tolerancia Inmunológica , Placenta/microbiología , Complicaciones Infecciosas del Embarazo/microbiología , Infecciones por Ureaplasma/microbiología , Ureaplasma/patogenicidad , Aborto Espontáneo/diagnóstico , Aborto Espontáneo/inmunología , Inmunidad Adaptativa , Apoptosis , Proteínas Reguladoras de la Apoptosis/genética , Estudios de Casos y Controles , Estudios Transversales , Citocinas/genética , Femenino , Regulación de la Expresión Génica , Histocompatibilidad Materno-Fetal/genética , Interacciones Huésped-Patógeno , Humanos , Tolerancia Inmunológica/genética , Inmunidad Innata , Placenta/inmunología , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/genética , Complicaciones Infecciosas del Embarazo/inmunología , Factores de Riesgo , Ureaplasma/inmunología , Infecciones por Ureaplasma/diagnóstico , Infecciones por Ureaplasma/genética , Infecciones por Ureaplasma/inmunología
4.
Front Vet Sci ; 8: 572171, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33681318

RESUMEN

The Mollicutes class encompasses wall-less microbes with a reduced genome. They may infect plants, insects, humans, and animals including those on farms and in livestock. Ureaplasma diversum is a mollicute associated with decreased reproduction mainly in the conception rate in cattle, as well as weight loss and decreased quality in milk production. Therefore, U. diversum infection contributes to important economic losses, mainly in large cattle-producing countries such as the United States, China, Brazil, and India. The characteristics of Mollicutes, virulence, and pathogenic variations make it difficult to control their infections. Genomic analysis, prevalence studies, and immunomodulation assays help better understand the pathogenesis of bovine ureaplasma. Here we present the main features of transmission, virulence, immune response, and pathogenesis of U. diversum in bovines.

5.
BMC Vet Res ; 16(1): 379, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-33028315

RESUMEN

BACKGROUND: Ureaplasma diversum has numerous virulence factors that contribute to pathogenesis in cattle, including Lipid-associated membrane proteins (LAMPs). Therefore, the objectives of this study were to evaluate in silico important characteristics for immunobiological applications and for heterologous expression of 36 LAMPs of U. diversum (UdLAMPs) and, also, to verify by conventional PCR the distribution of these antigens in strains of Brazilian states (Bahia, Minas Gerais, São Paulo, and Mato Grosso do Sul). The Manatee database was used to obtain the gene and peptide sequences of the antigens. Similarity and identity studies were performed using BLASTp and direct antigenicity was evaluated by the VaxiJen v2.0 server. Epitope prediction for B lymphocytes was performed on the BepiPred v2.0 and CBTOPE v1.0 servers. NetBoLApan v1.0 was used to predict CD8+ T lymphocyte epitopes. Subcellular location and presence of transmembrane regions were verified by the software PSORTb v3.0.2 and TMHMM v2.2 respectively. SignalP v5.0, SecretomeP v2.0, and DOLOP servers were used to predict the extracellular excretion signal. Physico-chemical properties were evaluated by the web-software ProtParam, Solpro, and Protein-sol. RESULTS: In silico analysis revealed that many UdLAMPs have desirable properties for immunobiological applications and heterologous expression. The proteins gudiv_61, gudiv_103, gudiv_517, and gudiv_681 were most promising. Strains from the 4 states were PCR positive for antigens predicted with immunogenic and/or with good characteristics for expression in a heterologous system. CONCLUSION: These works contribute to a better understanding of the immunobiological properties of the UdLAMPs and provide a profile of the distribution of these antigens in different Brazilian states.


Asunto(s)
Antígenos Bacterianos/genética , Proteínas Ligadas a Lípidos/inmunología , Ureaplasma/inmunología , Animales , Antígenos Bacterianos/química , Linfocitos B/inmunología , Brasil , Bovinos , Simulación por Computador , Proteínas Ligadas a Lípidos/genética , Ureaplasma/genética , Factores de Virulencia/genética , Factores de Virulencia/inmunología
6.
Infect Prev Pract ; 2(4): 100084, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34368723

RESUMEN

BACKGROUND: Staphylococcus aureus is a human pathogen of clinical importance related to a variety of infections. AIM: The objective of this study was to analyze the molecular and epidemiological characteristics of S. aureus obtained from healthcare professionals (HCP) of a hospital in southwestern Bahia, Brazil. METHODS: Samples were collected from hands, nasal cavity, and laboratory coats of 80 HCP. The bacterial isolates recovered from 240 samples were identified as S. aureus, and then analyzed for their antimicrobial resistance profile, genotypic characterization, and pathogenicity. FINDINGS: 178 isolates were identified as S. aureus, being mostly isolated from the nasal cavity. Thirty isolates (16.8%) were characterized as MRSA. The virulence gene frequency varied according to isolate source. All virulence genes were identified in at least one hand isolate. Isolates from laboratory coats did not show seb and pvl. Isolates from the nasal cavity did not exhibit pvl. The SCCmec type I was identified in 56.7% of MRSA isolates. Among MRSA isolates, 14 PFGE pulsotypes were characterized, with profile A being predominant (nine isolates). Clonal complexes CC5, CC45, and CC398 were found. MRSA isolates induced cytokine gene expression in macrophages, with IL-10 and IL-17 being expressed more often. CONCLUSION: We found a high colonization rate for S. aureus among HCP. Moreover, we observed that MRSA strains presented different virulence factors and could induce cytokine gene expression, indicating an urgent need to control colonization rates of HCP by MRSA isolates in order to protect hospital patients and the general public.

7.
Hematol., Transfus. Cell Ther. (Impr.) ; 41(4): 324-328, Oct.-Dec. 2019. tab
Artículo en Inglés | LILACS | ID: biblio-1056242

RESUMEN

ABSTRACT Introduction: The serological screening of blood donors has been instituted by the Brazilian Ministry of Health and is mandatory in the research on several diseases transmissible through blood transfusion. Blood banks need to establish a screening service capable of reducing associated transfusions risks. Objective: The objective of this study was to establish the prevalence of transfusion-transmissible infection markers in donors at a hemotherapy service located in southwest Bahia, Brazil. Methods: A retrospective study was performed between 2010 and 2016. Variables, such as the characterization of donors who were suitable and unsuitable for donation (in clinical screening), stratification by gender and age group and unsuitable samples for reactive test results (in serological screening) by aspecific antibodies against hepatitis B virus (anti-HBc and HBsAg), hepatitis C virus (anti-HCV), human T-lymphotropic virus (anti-HTLV I/II), HIV virus (anti-HIV I/II), chagas disease, and syphilis markers, were evaluated. Results: Collected data showed that 3.13% of the donors were considered unsuitable for serological screening and that the prevalence of reactive test results was higher in donors aged between 30 and 39 years and in males. The means of the serological markers was 1.09% for syphilis reagents, 0.63% for anti-HIV I/II, 0.51% for anti-HBc and anti-HCV, 0.15% for HBsAg, 0.14% for HTLV I/II and 0.10% for Chagas disease. Conclusion: These results reflect the importance of awareness campaigns on sexually transmitted diseases and transfusion safety measures taken by hemotherapy services.


Asunto(s)
Humanos , Masculino , Femenino , Donantes de Sangre , Biomarcadores , Estudios Seroepidemiológicos , Servicio de Hemoterapia , Infecciones de Transmisión Sanguínea
8.
Hematol Transfus Cell Ther ; 41(4): 324-328, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31412988

RESUMEN

INTRODUCTION: The serological screening of blood donors has been instituted by the Brazilian Ministry of Health and is mandatory in the research on several diseases transmissible through blood transfusion. Blood banks need to establish a screening service capable of reducing associated transfusions risks. OBJECTIVE: The objective of this study was to establish the prevalence of transfusion-transmissible infection markers in donors at a hemotherapy service located in southwest Bahia, Brazil. METHODS: A retrospective study was performed between 2010 and 2016. Variables, such as the characterization of donors who were suitable and unsuitable for donation (in clinical screening), stratification by gender and age group and unsuitable samples for reactive test results (in serological screening) by aspecific antibodies against hepatitis B virus (anti-HBc and HBsAg), hepatitis C virus (anti-HCV), human T-lymphotropic virus (anti-HTLV I/II), HIV virus (anti-HIV I/II), chagas disease, and syphilis markers, were evaluated. RESULTS: Collected data showed that 3.13% of the donors were considered unsuitable for serological screening and that the prevalence of reactive test results was higher in donors aged between 30 and 39 years and in males. The means of the serological markers was 1.09% for syphilis reagents, 0.63% for anti-HIV I/II, 0.51% for anti-HBc and anti-HCV, 0.15% for HBsAg, 0.14% for HTLV I/II and 0.10% for Chagas disease. CONCLUSION: These results reflect the importance of awareness campaigns on sexually transmitted diseases and transfusion safety measures taken by hemotherapy services.

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