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1.
Microb Pathog ; 195: 106909, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39218373

RESUMO

Brucellosis is a zoonotic disease caused by Brucella, which is difficult to eliminate by conventional drugs. Therefore, a novel multi-epitope vaccine (MEV) was designed to prevent human Brucella infection. Based on the method of "reverse vaccinology", cytotoxic T lymphocyte epitopes (CTLEs), helper T lymphocyte epitopes (HTLEs), linear B-cell epitopes (LBEs) and conformational B-cell epitopes (CBEs) of four Brucella proteins (VirB9, VirB10, Omp 19 and Omp 25) were obtained. In order to keep the correct protein folding, the multiple epitopes was constructed by connecting epitopes through linkers. In view of the significant connection between human leukocyte antigen CTLA-4 and B7 molecules found on antigen presenting cells (APCs), a new vaccine (V_C4MEV) for preventing brucellosis was created by combining CTLA-4 immunoglobulin variable region (IgV_CTLA-4) with MEV protein. Immunoinformatics analysis showed that V_C4MEV has a good secondary and tertiary structure. Additionally, molecular docking and molecular dynamics simulation (MD) revealed a robust binding affinity between IgV_ CTLA-4 and the B7 molecule. Notably, the vaccine V_C4MEV was demonstrated favorable immunogenicity and antigenicity in both in vitro and in vivo experiments. V_C4MEV had the potential to activate defensive cells and immune responses, offering a hopeful approach for developing vaccines against Brucella in the upcoming years.


Assuntos
Vacina contra Brucelose , Brucella , Brucelose , Antígeno CTLA-4 , Biologia Computacional , Epitopos de Linfócito B , Epitopos de Linfócito T , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Brucelose/prevenção & controle , Brucelose/imunologia , Epitopos de Linfócito B/imunologia , Antígeno CTLA-4/imunologia , Epitopos de Linfócito T/imunologia , Vacina contra Brucelose/imunologia , Animais , Humanos , Brucella/imunologia , Brucella/genética , Camundongos , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Imunoinformática , Lipoproteínas
2.
BMC Infect Dis ; 24(1): 929, 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39245722

RESUMO

BACKGROUND: Brucellosis is a global public health concern and occurs mainly in young adults and the elderly, with children having a lower incidence, thus often leading to delayed treatment. This study aimed to describe the epidemiologic features and clinical characteristics of brucellosis in children. METHODS: In this retrospective study, the clinical data of five children diagnosed with brucellosis in Anhui Provincial Children's Hospital between January 1, 2021 and December 30, 2022 were analyzed. RESULTS: All five cases were from non-pastoral areas, among which three have a history of livestock exposure and originated from the countryside. All patients had medium-high grade fever, mostly accompanied by night sweats and malaise, and three had joint pains. Laboratory tests showed that their white blood cell count was normal or mildly raised, with lymphocytes as the predominant cell population. Four patients had anemia, four had aspartate aminotransferase and alanine aminotransferase abnormality, and two had elevated ferritin levels. All blood samples were positive for Brucella culture, one of which had positive bone marrow culture, and all had positive serology test results. All patients were treated with rifampicin, in combination with sulfamethoxazole or doxycycline for 6 weeks following diagnosis. Four children had a good prognosis, but one child had recurrent joint pain. CONCLUSIONS: The epidemiologic history of children from non-pastoral areas with brucellosis is often unclear; clinical manifestations and laboratory tests lack specificity; and they are easily delayed diagnosis. Clinicians should remain vigilant regarding the possibility of this disease in children with fever of unknown origin. The epidemiological history should be investigated in detail to improve the diagnostic ability of brucellosis. We recommend emphasizing serological testing. Children with brucellosis who receive timely diagnosis and standardized treatment can expect a favorable prognosis.


Assuntos
Antibacterianos , Brucelose , Brucelose/epidemiologia , Brucelose/diagnóstico , Brucelose/tratamento farmacológico , Humanos , Masculino , Feminino , Criança , Estudos Retrospectivos , Antibacterianos/uso terapêutico , Pré-Escolar , Doxiciclina/uso terapêutico , China/epidemiologia , Brucella/isolamento & purificação , Rifampina/uso terapêutico , Sulfametoxazol/uso terapêutico , Febre/microbiologia , Febre/etiologia , Adolescente
3.
J Math Biol ; 89(4): 39, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39249563

RESUMO

To explore the influence of state changes on brucellosis, a stochastic brucellosis model with semi-Markovian switchings and diffusion is proposed in this paper. When there is no switching, we introduce a critical value R s and obtain the exponential stability in mean square when R s < 1 by using the stochastic Lyapunov function method. Sudden climate changes can drive changes in transmission rate of brucellosis, which can be modelled by a semi-Markov process. We study the influence of stationary distribution of semi-Markov process on extinction of brucellosis in switching environment including both stable states, during which brucellosis dies out, and unstable states, during which brucellosis persists. The results show that increasing the frequencies and average dwell times in stable states to certain extent can ensure the extinction of brucellosis. Finally, numerical simulations are given to illustrate the analytical results. We also suggest that herdsmen should reduce the densities of animal habitation to decrease the contact rate, increase slaughter rate of animals and apply disinfection measures to kill brucella.


Assuntos
Brucelose , Simulação por Computador , Cadeias de Markov , Conceitos Matemáticos , Modelos Biológicos , Processos Estocásticos , Brucelose/transmissão , Brucelose/epidemiologia , Brucelose/microbiologia , Animais , Humanos , Modelos Epidemiológicos , Brucella/patogenicidade , Mudança Climática
4.
Pan Afr Med J ; 48: 23, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39220558

RESUMO

Introduction: brucellosis is a global neglected zoonotic disease affecting mainly livestock, causing communicable and zoonotic infections. This study aimed to investigate the seroprevalence and determine epidemiological risk factors associated with Brucella infection in sheep and goats in Al Jufrah central district of Libya. Methods: sera samples from 555 animals (goats (n=320) and sheep (n=235)) sheep) were obtained and subjected to the Rose Bengal Plate Test (RBPT) then further confirmed by a validated Enzyme Linked Immunosorbent assay (ELISA). Collected data was analyzed using Statistical Package for the Social Sciences (SPSS). Results: in total, 2.7% were ELISA seropositive for brucellosis with the highest seropositivity rate among the studied animals from Sokna with 5.8% (n=13/225) followed by 0.7% (n=2/285) in Waddan and 0% (n=0/45) in Houn. Only location was identified as a significant risk and no significant differences were identified between seropositivity and the age studied groups, species of animals, gender, and size of farms (p-value>0.05). Conclusion: the present study provides important information on the epidemiological status of Brucella infection in an important region in North Africa. Prevention control systems adopting "One Health" concept, and regional and international collaboration are important to control brucellosis and other zoonotic and transboundary diseases.


Assuntos
Brucelose , Ensaio de Imunoadsorção Enzimática , Doenças das Cabras , Cabras , Doenças dos Ovinos , Zoonoses , Animais , Brucelose/epidemiologia , Estudos Soroepidemiológicos , Líbia/epidemiologia , Doenças das Cabras/epidemiologia , Doenças das Cabras/microbiologia , Ovinos , Feminino , Masculino , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/microbiologia , Fatores de Risco , Zoonoses/epidemiologia , Brucella/isolamento & purificação , Brucella/imunologia
5.
Life Sci ; 355: 122986, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39151885

RESUMO

Brucellosis is a chronic infectious disease that is zoonotic in nature. Brucella can infect humans through interactions with livestock, primarily via the digestive tract, respiratory tract, and oral cavity. This bacterium has the potential to be utilized as a biological weapon and is classified as a Category B pathogen by the Centers for Disease Control and Prevention. Currently, there is no approved vaccine for humans against Brucella, highlighting an urgent need for the development of a vaccine to mitigate the risks posed by this pathogen. Brucella primarily infects its host by adhering to and penetrating mucosal surfaces. Mucosal immunity plays a vital role in preventing local infections, clearing microorganisms from mucosal surfaces, and inhibiting the spread of pathogens. As mucosal vaccine strategies continue to evolve, the development of a safe and effective mucosal vaccine against Brucella appears promising.This paper reviews the immune mechanism of mucosal vaccines, the infection mechanism of Brucella, successful Brucella mucosal vaccines in animals, and mucosal adjuvants. Additionally, it elucidates targeting and optimization strategies for mucosal vaccines to facilitate the development of human vaccines against Brucella.


Assuntos
Vacina contra Brucelose , Brucella , Brucelose , Imunidade nas Mucosas , Humanos , Animais , Brucella/imunologia , Imunidade nas Mucosas/imunologia , Brucelose/prevenção & controle , Brucelose/imunologia , Brucelose/microbiologia , Vacina contra Brucelose/imunologia , Adjuvantes Imunológicos , Desenvolvimento de Vacinas
6.
Biosensors (Basel) ; 14(8)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39194633

RESUMO

Brucellosis in animals is an infectious disease caused by bacteria of the genus Brucella. Known methods for diagnosing brucellosis face some challenges, due to the difficulties in isolating and standardizing the natural brucellosis antigen. In this work, we investigated the possibility of using the fluorescence polarization assay (FPA) with synthetic glycoconjugate biosensing tracers to detect antibodies against Brucella as a new methodology for diagnosing brucellosis. Based on the received results, the synthetic fluorescein-labeled trisaccharide tracer is most effective for Brucellosis detection. This tracer is structurally related to the immune determinant fragment of the Brucella LPS buildup of N-formyl-d-perosamine units, connected via α-(1→3)-linkage at the non-reducing end and α-(1→2)-linkage at the reducing end. The sensitivity and specificity in the case of the use of trisaccharide tracer 3b were 71% and 100% (Yuden's method) and 87% and 88% (Euclidean method), respectively, which is comparable with the diagnostic efficiency of traditionally used serological methods, such as the agglutination test (AT), complement fixation test (CFT), and Rose Bengal test (RBT). Given the known advantages of FPA (e.g., speed, compactness of the equipment, and standard reagents) and the increased specificity of the developed test system, it would be appropriate to consider its widespread use for the diagnosis of brucellosis in animals, including rapid testing in the field.


Assuntos
Técnicas Biossensoriais , Brucella , Brucelose , Oligossacarídeos , Brucelose/diagnóstico , Técnicas Biossensoriais/métodos , Animais , Polarização de Fluorescência , Corantes Fluorescentes
7.
Cytokine ; 182: 156711, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39094437

RESUMO

BACKGROUND: Brucellosis is an economically important infectious caused by most commonly by Brucella. Detection of infected animals at the early stage is important for controlling the disease. The diagnostic antigens, usually protein antigens, have attracted much interest. However, the accurate mechanism of immune response is still unknown. The secretory effectors (BPE005, BPE275, and BPE123) of the type IV secretion system (T4SS) were involved in the intracellular circulation process of Brucella and the immune responses of the host. METHODS: Genes encoding three B. abortus effector proteins (BPE005, BPE275, and BPE123) of T4SS were cloned and the recombinant proteins were expressed and purified. The purified recombinant proteins were named rBPE005, rBPE275 and rBPE123. Then, the expressions of Th1- and Th2-related cytokine genes were analyzed in mice bone marrow-derived macrophages (BMDMs) after stimulation with rBPE005, rBPE275, and rBPE123. Furthermore, four apoptosis-associated genes (Caspase-3, Caspase-8, Bax, and Bcl-2) were also detected to explore the damage of the proteins to the cells. RESULTS: Expressions of all Th1- and Th2-related cytokine genes were induced with three proteins, and different cytokine expression patterns induced by each protein depend on the stimulation time and dose of protein. However, expressions of apoptosis-related genes did not change. CONCLUSION: These results showed that the secreted antigens of Brucella induced an immune reaction via the production of Th1- and Th2-type cytokines in BMDMs without exerting any damage on the cells.


Assuntos
Apoptose , Proteínas de Bactérias , Citocinas , Macrófagos , Proteínas Recombinantes , Sistemas de Secreção Tipo IV , Animais , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Citocinas/metabolismo , Sistemas de Secreção Tipo IV/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Camundongos Endogâmicos BALB C , Brucella abortus/imunologia , Brucelose/imunologia , Brucelose/genética , Feminino , Brucella/imunologia , Células Th1/imunologia
9.
Genome Biol ; 25(1): 170, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951884

RESUMO

Microbial pangenome analysis identifies present or absent genes in prokaryotic genomes. However, current tools are limited when analyzing species with higher sequence diversity or higher taxonomic orders such as genera or families. The Roary ILP Bacterial core Annotation Pipeline (RIBAP) uses an integer linear programming approach to refine gene clusters predicted by Roary for identifying core genes. RIBAP successfully handles the complexity and diversity of Chlamydia, Klebsiella, Brucella, and Enterococcus genomes, outperforming other established and recent pangenome tools for identifying all-encompassing core genes at the genus level. RIBAP is a freely available Nextflow pipeline at github.com/hoelzer-lab/ribap and zenodo.org/doi/10.5281/zenodo.10890871.


Assuntos
Genoma Bacteriano , Anotação de Sequência Molecular , Software , Brucella/genética , Brucella/classificação , Bactérias/genética , Bactérias/classificação , Chlamydia/genética , Enterococcus/genética , Klebsiella/genética
10.
Medicina (Kaunas) ; 60(7)2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39064560

RESUMO

Background and Objectives: Differentiation between brucella spondylodiscitis and Modic type I changes (MC1) includes difficulties. Hematological inflammatory indices (HII) such as neutrophil to lymphocyte ratio (NLR) and aggregate index of systemic inflammation (AISI) are suggested as indicators of inflammation and infection and have diagnostic, prognostic, and predictive roles in various diseases. This study aimed to evaluate differences between brucella spondylodiscitis and MC1 in terms of HII. Materials and Methods: Thirty-five patients with brucella spondylodiscitis and thirty-seven with MC1 were enrolled in the study. Brucella spondylodiscitis and MC1 were diagnosed by microbiological, serological, and radiological diagnostic tools. HII (NLR, MLR, PLR, NLPR, SII, SIRI, AISI) were derived from baseline complete blood count. Results: The two groups were similar for age (p = 0.579) and gender (p = 0.092), leukocyte (p = 0.127), neutrophil (p = 0.366), lymphocyte (p = 0.090), and monocyte (p = 0.756) scores. The Brucella spondylodiscitis group had significantly lower pain duration (p < 0.001), higher CRP and ESR levels (p < 0.001), and lower platelet count (p = 0.047) than the MC1 group. The two groups had similarity in terms of HII: NLR (p = 0.553), MLR (p = 0.294), PLR (p = 0.772), NLPR (p = 0.115), SII (p = 0.798), SIRI (p = 0.447), and AISI (p = 0.248). Conclusions: Increased HII can be used to differentiate infectious and non-infectious conditions, but this may be invalid in brucellosis. However, pain duration, CRP and ESR levels, and platelet count may be useful to distinguish brucella spondylodiscitis from MC1.


Assuntos
Brucelose , Discite , Humanos , Discite/sangue , Discite/diagnóstico , Discite/microbiologia , Feminino , Masculino , Pessoa de Meia-Idade , Brucelose/diagnóstico , Brucelose/sangue , Adulto , Idoso , Diagnóstico Diferencial , Inflamação/sangue , Brucella/isolamento & purificação , Brucella/imunologia , Neutrófilos
11.
J Infect Dev Ctries ; 18(7): 1066-1073, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39078792

RESUMO

INTRODUCTION: In our study, we aimed to evaluate the epidemiological features of brucellosis and the efficacy of different treatment options in patients with various organ involvements. METHODOLOGY: Patients diagnosed with brucellosis and treated in two different centers between 2009 and 2019 were retrospectively screened and evaluated regarding epidemiological and clinical features, laboratory findings, and treatment responses. RESULTS: The study included 297 complete-data patients (76% of rural patients were farmers). Farming (76%) and raw dairy (69%) were the main transmission methods. Most patients (98.6%) had positive tube agglutination tests. Ninety-two patients' blood and bodily fluid cultures grew Brucella spp. The incidence of leukopenia was 18.8%, thrombocytopenia 10.7%, anemia 34.3%, and pancytopenia 4.3%. Doxycycline and rifampicin were the major treatments, with streptomycin utilized in osteoarticular patients. Pregnant women with neurobrucellosis took ceftriaxone and trimethoprim-sulfamethoxazole. After one year, 7.1% of patients relapsed. Doxycycline + streptomycin and doxycycline + rifampicin had similar relapse rates (p = 0.799). The double- and triple-antibiotic groups had identical recurrence rates (p = 0.252). CONCLUSIONS: In uncomplicated brucellosis cases doxycycline + streptomycin and doxycycline + rifampicin treatments were equally effective. Again, there is no statistical difference in relapse development rates between double and triple combination treatments in uncomplicated brucellosis cases. Relapsed patients generally miss follow-ups, interrupt therapy, have osteoarticular involvement, and get short-term treatment. Patients with focused participation should be thoroughly checked at diagnosis and medicine, and treatment should be lengthy to prevent relapses.


Assuntos
Antibacterianos , Brucelose , Doxiciclina , Rifampina , Estreptomicina , Humanos , Brucelose/tratamento farmacológico , Brucelose/epidemiologia , Turquia/epidemiologia , Feminino , Adulto , Masculino , Estudos Retrospectivos , Antibacterianos/uso terapêutico , Pessoa de Meia-Idade , Doxiciclina/uso terapêutico , Estreptomicina/uso terapêutico , Rifampina/uso terapêutico , Adulto Jovem , Adolescente , Idoso , Gravidez , Brucella/efeitos dos fármacos , Brucella/isolamento & purificação , Quimioterapia Combinada
12.
Diagn Microbiol Infect Dis ; 110(1): 116432, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39024932

RESUMO

In recent years, immunization with the S2 live-attenuated vaccine has been recognized as the most economical and effective strategy for preventing brucellosis in Inner Mongolia, China. However, there are still challenges related to vaccine toxicity and the inability to distinguish between vaccine immunization and natural infection. Therefore, in this study, we developed a digital droplet polymerase chain reaction (ddPCR) assay based on single-nucleotide polymorphism (SNP) loci to identify wild Brucella strains and S2 vaccine strains. The assay demonstrated excellent linearity (R2> 0.99) with a lower detection limit of 10 copies/µL for both wild and vaccine strains. Additionally, the ddPCR assay outperformed the real-time fluorescent quantitative PCR (qPCR) assay in screening 50 clinical samples. We have established an effective and highly sensitive ddPCR assay for Brucella, providing an efficient method for detecting and differentiating wild strains of Brucella from the S2 vaccine strain.


Assuntos
Vacina contra Brucelose , Brucella , Brucelose , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Brucella/genética , Brucella/classificação , Brucella/isolamento & purificação , Humanos , Vacina contra Brucelose/genética , Vacina contra Brucelose/imunologia , Brucelose/diagnóstico , Brucelose/prevenção & controle , Brucelose/microbiologia , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade , China , Vacinas Atenuadas/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , DNA Bacteriano/genética
13.
Diagn Microbiol Infect Dis ; 110(1): 116396, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38950487

RESUMO

BACKGROUND: Brucellosis is a zoonosis endemic to specific geographical regions. In first line laboratories, diagnosis is made by blood culture or Rose Bengal (RB) serology. METHODS: We compare brucellosis testing between 2012-2021 at two university hospitals in Brussels, Belgium with concomitant national confirmed cases and institutional cases. RESULTS: RB testing increased from 30 to 211 tests/year between 2012-2021. A total of fifty-two national brucellosis cases were notified during the study period, of which fifteen cases in Brussels. No trend was noted nationally or regionally. Epidemiological data indicated travel to endemic regions, confirmed by strain testing. Institutional cases all showed symptomatic presentations with positive travel histories. CONCLUSIONS: Serologic testing inappropriately increases yearly, while annual imported brucellosis cases remain rare, and have positive travel histories and are symptomatic. We therefore support current recommendations of limiting RB testing to symptomatic patients at risk of exposure, meaning predominantly positive recent travel history.


Assuntos
Brucelose , Rosa Bengala , Testes Sorológicos , Brucelose/diagnóstico , Brucelose/epidemiologia , Humanos , Masculino , Feminino , Bélgica/epidemiologia , Adulto , Pessoa de Meia-Idade , Idoso , Viagem , Adulto Jovem , Brucella/imunologia , Brucella/isolamento & purificação , Hospitais Universitários/estatística & dados numéricos
14.
Reprod Domest Anim ; 59(7): e14672, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39034616

RESUMO

Animal reproduction biotechniques are important tools for the technological advancement of livestock, as they allow the selection of the reproductive potential of superior quality females and males; however, infectious diseases that have a predilection for the reproductive system can be a hindrance for the use of these technologies. Therefore, the present study aimed to detect Brucella spp. in the ovarian follicular fluid of brucellosis-positive bovine cows. A total of 47 bovine ovarian follicular fluid aspirates from cows, positive in tests for brucellosis and from Brucella-positive herd, were submitted to PCR. The primers used in the PCR were specific to the genus Brucella (bcsp31 gene). All 47 bovine aspirates were negative for Brucella spp. 0.00% (95% CI: 0.00-4.00%). Our results demonstrated that Brucella spp. was absent in the ovarian follicular fluid from seropositive cows, which indicates that Brucella spp.-infected cows could be used for reproductive biotechnologies carried out with follicular aspirates. Future studies are needed to more precisely evaluate the feasibility and safety of using these oocytes from brucellosis-seropositive cows to transfer embryos to heifers/cows not infected by Brucella, aiming to produce calves free of the infection.


Assuntos
Brucelose Bovina , Líquido Folicular , Bovinos , Animais , Feminino , Líquido Folicular/química , Brucelose Bovina/microbiologia , Brucella/isolamento & purificação , Fertilização in vitro/veterinária , Reação em Cadeia da Polimerase/veterinária , Doenças dos Bovinos/microbiologia
15.
Infect Genet Evol ; 123: 105625, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38906517

RESUMO

The genus Pseudochrobactrum encompasses free-living bacteria phylogenetically close to Ochrobactrum opportunistic pathogens and to Brucella, facultative intracellular parasites causing brucellosis, a worldwide-extended and grave zoonosis. Recently, Pseudochrobactrum strains were isolated from Brucella natural hosts on Brucella selective media, potentially causing diagnostic confusions. Strikingly, P. algeriensis was isolated from cattle lymph nodes, organs that are inimical to bacteria. Here, we analyse P. algeriensis potential virulence factors in comparison with Ochrobactrum and Brucella. Consistent with genomic analyses, Western-Blot analyses confirmed that P. algeriensis lacks the ability to synthesize the N-formylperosamine O-polysaccharide characteristic of the lipopolysaccharide (LPS) of smooth Brucella core species. However, unlike other Pseudochrobactrum but similar to some early diverging brucellae, P. algeriensis carries genes potentially synthetizing a rhamnose-based O-polysaccharide LPS. Lipid A analysis by MALDI-TOF demonstrated that P. algeriensis LPS bears a lipid A with a reduced pathogen-associated molecular pattern, a trait shared with Ochrobactrum and Brucella that is essential to generate a highly stable outer membrane and to delay immune activation. Also, although not able to multiply intracellularly in macrophages, the analysis of P. algeriensis cell lipid envelope revealed the presence of large amounts of cationic aminolipids, which may account for the extremely high resistance of P. algeriensis to bactericidal peptides and could favor colonization of mucosae and transient survival in Brucella hosts. However, two traits critical in Brucella pathogenicity are either significantly different (T4SS [VirB]) or absent (erythritol catabolic pathway) in P. algeriensis. This work shows that, while diverging in other characteristics, lipidic envelope features relevant in Brucella pathogenicity are conserved in Brucellaceae. The constant presence of these features strongly suggests that reinforcement of the envelope integrity as an adaptive advantage in soil was maintained in Brucella because of the similarity of some environmental challenges, such as the action of cationic peptide antibiotics and host defense peptides. This information adds knowledge about the evolution of Brucellaceae, and also underlines the taxonomical differences of the three genera compared.


Assuntos
Filogenia , Animais , Fatores de Virulência/genética , Brucellaceae/genética , Brucellaceae/metabolismo , Brucella/genética , Brucella/classificação , Lipopolissacarídeos/metabolismo , Genoma Bacteriano , Ochrobactrum/genética , Bovinos , Brucelose/microbiologia , Lipídeo A/metabolismo , Lipídeo A/química
16.
mBio ; 15(7): e0072624, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38847540

RESUMO

The modulation of actin polymerization is a common theme among microbial pathogens. Even though microorganisms show a wide repertoire of strategies to subvert the activity of actin, most of them converge in the ones that activate nucleating factors, such as the Arp2/3 complex. Brucella spp. are intracellular pathogens capable of establishing chronic infections in their hosts. The ability to subvert the host cell response is dependent on the capacity of the bacterium to attach, invade, avoid degradation in the phagocytic compartment, replicate in an endoplasmic reticulum-derived compartment and egress. Even though a significant number of mechanisms deployed by Brucella in these different phases have been identified and characterized, none of them have been described to target actin as a cellular component. In this manuscript, we describe the identification of a novel virulence factor (NpeA) that promotes niche formation. NpeA harbors a short linear motif (SLiM) present within an amphipathic alpha helix that has been described to bind the GTPase-binding domain (GBD) of N-WASP and stabilizes the autoinhibited state. Our results show that NpeA is secreted in a Type IV secretion system-dependent manner and that deletion of the gene diminishes the intracellular replication capacity of the bacterium. In vitro and ex vivo experiments demonstrate that NpeA binds N-WASP and that the short linear motif is required for the biological activity of the protein.IMPORTANCEThe modulation of actin-binding effectors that regulate the activity of this fundamental cellular protein is a common theme among bacterial pathogens. The neural Wiskott-Aldrich syndrome protein (N-WASP) is a protein that several pathogens target to hijack actin dynamics. The highly adapted intracellular bacterium Brucella has evolved a wide repertoire of virulence factors that modulate many activities of the host cell to establish successful intracellular replication niches, but, to date, no effector proteins have been implicated in the modulation of actin dynamics. We present here the identification of a virulence factor that harbors a short linear motif (SLiM) present within an amphipathic alpha helix that has been described to bind the GTPase-binding domain (GBD) of N-WASP stabilizing its autoinhibited state. We demonstrate that this protein is a Type IV secretion effector that targets N-WASP-promoting intracellular survival and niche formation.


Assuntos
Proteínas de Bactérias , Fatores de Virulência , Proteína Neuronal da Síndrome de Wiskott-Aldrich , Fatores de Virulência/metabolismo , Fatores de Virulência/genética , Proteína Neuronal da Síndrome de Wiskott-Aldrich/metabolismo , Proteína Neuronal da Síndrome de Wiskott-Aldrich/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Humanos , Sistemas de Secreção Tipo IV/metabolismo , Sistemas de Secreção Tipo IV/genética , Animais , Camundongos , Ligação Proteica , Brucella/metabolismo , Brucella/genética , Brucella/patogenicidade , Motivos de Aminoácidos , Actinas/metabolismo , Brucelose/microbiologia , Macrófagos/microbiologia , Interações Hospedeiro-Patógeno
17.
Eur J Clin Microbiol Infect Dis ; 43(8): 1651-1654, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38856827

RESUMO

Any system or organ involvement can be seen in brucellosis, which is still a significant public health problem in developing countries. The rate of respiratory system involvement is lower than that of other systems and which is also difficult to document. Brucellosis-associated pleurisy is a rare complication even in endemic regions. In this case report, a 78-year-old male patient who was assessed for pleural effusion etiology is presented. Brucella spp. were isolated on the 14th day of the pleural fluid incubation in the blood culture set and the patienthas been treated successfully for brucellosis. Based on our experience we think that it is important to use blood culture media for sterile body fluids, particularly for microorganisms that are difficult to isolate such as Brucella spp.


Assuntos
Brucella , Brucelose , Pleurisia , Humanos , Masculino , Brucelose/diagnóstico , Brucelose/tratamento farmacológico , Brucelose/microbiologia , Idoso , Pleurisia/microbiologia , Brucella/isolamento & purificação , Derrame Pleural/microbiologia , Antibacterianos/uso terapêutico , Resultado do Tratamento
18.
Med Trop Sante Int ; 4(1)2024 03 31.
Artigo em Francês | MEDLINE | ID: mdl-38846127

RESUMO

Introduction: Brucellosis in marine mammals (cetacean and pinnipeds) has emerged in a very significant way during the last two decades. Currently Brucella ceti and Brucella pinnipedialis are the two recognized species in marine mammals, but available information is still limited. Several genotypes have been identified, and studies on the relationship between sequence type (ST) and organ pathogenicity or tropism have indicated differences in pathogenesis between B. ceti sequences in cetaceans. The zoonotic potential of this disease is based on the identification of the main sources of introduction and spread of Brucella spp. in the marine environment as well as on the factors of exposure of marine mammals and humans to the bacteria. Bibliographic review: This article is a bibliographical review on marine mammal brucellosis, including the features, sources and transmission modes of each Brucella species, as well as their potential pathogenicity in animals and humans. Conclusion: Different genotypes of marine Brucella spp have been isolated from marine mammal species but without any evidence of pathology induced by these bacteria. Associated lesions are variable and include subcutaneous abscesses, meningo-encephalomyelitis, pneumonia, myocarditis, osteoarthritis, orchitis, endometritis, placentitis and abortion. The isolation of marine B. spp from marine mammal respiratory parasites associated to lung injury has raised the intriguing possibility that they may serve as a vector for the transmission of this bacterium.The severity of marine B. spp remains unknown due to the lack of an estimate of the prevalence of this disease in marine mammals. The number of suspected human cases is still very limited. However, by analogy with other germs of the genus Brucella responsible for abortion in ruminants and for a febrile and painful state in human beings, prevention measures are essential. The significant increase in the number of strandings coupled with a high seroprevalence in certain species of marine mammals must be considered for people in direct or indirect contact with these animals. Ongoing epidemiological monitoring combined with extensive post-mortem examinations (necropsy, bacteriology and sequencing) of all species of stranded marine mammals would deepen knowledge on the zoonotic potential of marine Brucella species.


Assuntos
Brucella , Brucelose , Caniformia , Cetáceos , Animais , Brucelose/transmissão , Brucelose/veterinária , Brucelose/microbiologia , Brucelose/epidemiologia , Humanos , Brucella/patogenicidade , Brucella/isolamento & purificação , Brucella/genética , Cetáceos/microbiologia , Caniformia/microbiologia , Zoonoses/microbiologia , Zoonoses/transmissão
19.
Prev Vet Med ; 229: 106240, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38850872

RESUMO

Brucellosis poses a major public and animal health problem in many parts of the world, particularly in pastoral settings, however, seroepidemological studies are scarce. A cross-sectional study was conducted from December 2021 to April 2022 to estimate the prevalence of brucellosis and to identify the associated risk factors for camels and occupational individuals from three purposively selected districts of the Somali pastoral region in Eastern Ethiopia. Serum samples were serially diluted using the Rose Bengal Plate Test (RBPT) as a screening test and a competitive Enzyme-Linked Immunosorbent Assay (cELISA) test as a confirmatory test. From a total of 450 camels and 250 human serum samples tested, the overall seroprevalence was confirmed to be 2.9 % (95 % CI, 1.5-4.9) in camels and 2.0 % (95 % CI, 0.2-3.7) in humans. In camels, abortion and retained fetal membrane (RFM) were significant risk factors for Brucella seropositivity (p<0.05). However, in humans, RFM disposal differed significantly (p<0.05). The fact that brucellosis is found in both camels and humans highlights the importance of implementing a coordinated One Health approach to control and eliminate the disease. This would ensure improved public health and increased livestock productivity.


Assuntos
Brucelose , Camelus , Brucelose/epidemiologia , Brucelose/veterinária , Estudos Soroepidemiológicos , Animais , Etiópia/epidemiologia , Fatores de Risco , Estudos Transversais , Humanos , Feminino , Masculino , Adulto , Prevalência , Brucella/isolamento & purificação , Brucella/imunologia , Pessoa de Meia-Idade , Adulto Jovem , Criação de Animais Domésticos , Ensaio de Imunoadsorção Enzimática/veterinária
20.
Front Public Health ; 12: 1396152, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841672

RESUMO

Background: Spondylitis caused by Brucella infection is a rare but challenging condition, and its successful management depends on timely diagnosis and appropriate treatment. This study reports two typical cases of thoracic and lumbar brucellosis spondylitis, highlighting the pivotal roles of real-time polymerase chain reaction (real-time PCR) detection and surgical intervention. Case presentation: Case 1 involved a 49-year-old male shepherd who presented with a 6-month history of fever (40°C), severe chest and back pain, and 2-week limited lower limb movement with night-time exacerbation. Physical examination revealed tenderness and percussion pain over the T9 and T10 spinous processes, with grade 2 muscle strength in the lower limbs. CT showed bone destruction of the T9 and T10 vertebrae with narrowing of the intervertebral space, whereas MRI demonstrated abnormal signals in the T9-T10 vertebrae, a spinal canal abscess, and spinal cord compression. The Rose Bengal plate agglutination test was positive. Case 2 was a 59-year-old man who complained of severe thoracolumbar back pain with fever (39.0°C) and limited walking for 2 months. He had a 2.5 kg weight loss and a history of close contact with sheep. The Rose Bengal test was positive, and the MRI showed inflammatory changes in the L1 and L2 vertebrae. Diagnosis and treatment: real-time PCR confirmed Brucella infection in both cases. Preoperative antimicrobial therapy with doxycycline, rifampicin, and ceftazidime-sulbactam was administered for at least 2 weeks. Surgical management involved intervertebral foraminotomy-assisted debridement, decompression, internal fixation, and bone grafting under general anesthesia. Postoperative histopathological examination with HE and Gram staining further substantiated the diagnosis. Outcomes: both patients experienced significant pain relief and restored normal lower limb movement at the last follow-up (4-12 weeks) after the intervention. Conclusion: Real-time PCR detection offers valuable diagnostic insights for suspected cases of brucellosis spondylitis. Surgical treatment helps in infection control, decompression of the spinal cord, and restoration of stability, constituting a necessary and effective therapeutic approach. Prompt diagnosis and comprehensive management are crucial for favorable outcomes in such cases.


Assuntos
Brucelose , Vértebras Lombares , Reação em Cadeia da Polimerase em Tempo Real , Espondilite , Vértebras Torácicas , Humanos , Masculino , Brucelose/cirurgia , Brucelose/diagnóstico , Brucelose/tratamento farmacológico , Pessoa de Meia-Idade , Espondilite/cirurgia , Espondilite/diagnóstico por imagem , Espondilite/tratamento farmacológico , Vértebras Lombares/cirurgia , Vértebras Torácicas/cirurgia , Brucella/isolamento & purificação , Antibacterianos/uso terapêutico , Imageamento por Ressonância Magnética
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