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1.
Clin Nucl Med ; 49(8): e406-e407, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38967511

RESUMO

ABSTRACT: FDG PET/CT is a well-documented imaging investigation to evaluate fever of unknown origin (FUO). Brucellosis is one of the causes of FUO, which can be missed as it requires a longer incubation period for growth on culture media. Rarely, it can involve the prostate. Here, we present a case of FUO with initial negative blood and urine cultures and no localizing signs or symptoms. 18F-FDG PET/CT revealed hypermetabolism in the prostate and seminal vesicles. A repeat blood and urine culture showed the growth of Brucella species after 5 days of incubation, and the patient responded to Brucella-directed antibiotic therapy.


Assuntos
Brucelose , Febre de Causa Desconhecida , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prostatite , Humanos , Masculino , Febre de Causa Desconhecida/diagnóstico por imagem , Prostatite/diagnóstico por imagem , Prostatite/microbiologia , Brucelose/diagnóstico por imagem , Brucelose/complicações , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
2.
PLoS One ; 19(7): e0306429, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38980867

RESUMO

Brucella abortus (Ba) is a pathogen that survives inside macrophages. Despite being its preferential niche, Ba infects other cells, as shown by the multiple signs and symptoms humans present. This pathogen can evade our immune system. Ba displays a mechanism of down-modulating MHC-I on monocytes/macrophages in the presence of IFN-γ (when Th1 response is triggered) without altering the total expression of MHC-I. The retained MHC-I proteins are located within the Golgi Apparatus (GA). The RNA of Ba is one of the PAMPs that trigger this phenomenon. However, we acknowledged whether this event could be triggered in other cells relevant during Ba infection. Here, we demonstrate that Ba RNA reduced the surface expression of MHC-I induced by IFN-γ in the human bronchial epithelium (Calu-6), the human alveolar epithelium (A-549) and the endothelial microvasculature (HMEC) cell lines. In Calu-6 and HMEC cells, Ba RNA induces the retention of MHC-I in the GA. This phenomenon was not observed in A-549 cells. We then evaluated the effect of Ba RNA on the secretion of IL-8, IL-6 and MCP-1, key cytokines in Ba infection. Contrary to our expectations, HMEC, Calu-6 and A-549 cells treated with Ba RNA had higher IL-8 and IL-6 levels compared to untreated cells. In addition, we showed that Ba RNA down-modulates the MHC-I surface expression induced by IFN-γ on human monocytes/macrophages via the pathway of the Epidermal Growth Factor Receptor (EGFR). So, cells were stimulated with an EGFR ligand-blocking antibody (Cetuximab) and Ba RNA. Neutralization of the EGFR to some extent reversed the down-modulation of MHC-I mediated by Ba RNA in HMEC and A-549 cells. In conclusion, this is the first study exploring a central immune evasion strategy, such as the downregulation of MHC-I surface expression, beyond monocytes and could shed light on how it persists effectively within the host, enduring unseen and escaping CD8+ T cell surveillance.


Assuntos
Brucella abortus , Células Endoteliais , Células Epiteliais , Antígenos de Histocompatibilidade Classe I , Interferon gama , Humanos , Interferon gama/metabolismo , Interferon gama/farmacologia , Células Endoteliais/metabolismo , Células Endoteliais/microbiologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe I/genética , RNA Bacteriano/genética , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Receptores ErbB/metabolismo , Brucelose/imunologia , Brucelose/metabolismo , Brucelose/microbiologia , Brucelose/genética , Complexo de Golgi/metabolismo , Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/microbiologia , Monócitos/metabolismo , Monócitos/imunologia , Monócitos/efeitos dos fármacos
3.
Nat Commun ; 15(1): 6132, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033187

RESUMO

Brucella melitensis is a major livestock bacterial pathogen and zoonosis, causing disease and infection-related abortions in small ruminants and humans. A considerable burden to animal-based economies today, the presence of Brucella in Neolithic pastoral communities has been hypothesised but we lack direct genomic evidence thus far. We report a 3.45X B. melitensis genome preserved in an ~8000 year old sheep specimen from Mentese Höyük, Northwest Türkiye, demonstrating that the pathogen had evolved and was circulating in Neolithic livestock. The genome is basal with respect to all known B. melitensis and allows the calibration of the B. melitensis speciation time from the primarily cattle-infecting B. abortus to approximately 9800 years Before Present (BP), coinciding with a period of consolidation and dispersal of livestock economies. We use the basal genome to timestamp evolutionary events in B. melitensis, including pseudogenization events linked to erythritol response, the supposed determinant of the pathogen's placental tropism in goats and sheep. Our data suggest that the development of herd management and multi-species livestock economies in the 11th-9th millennium BP drove speciation and host adaptation of this zoonotic pathogen.


Assuntos
Brucella melitensis , Brucelose , Genoma Bacteriano , Zoonoses , Brucella melitensis/genética , Brucella melitensis/isolamento & purificação , Animais , Ovinos/microbiologia , Genoma Bacteriano/genética , Brucelose/microbiologia , Brucelose/veterinária , Brucelose/história , Humanos , Zoonoses/microbiologia , Filogenia , Bovinos , Zoonoses Bacterianas/microbiologia , Cabras/microbiologia , Evolução Molecular , Gado/microbiologia , História Antiga , Doenças dos Ovinos/microbiologia , Feminino
4.
Open Vet J ; 14(5): 1081-1097, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38938422

RESUMO

One zoonotic infectious animal disease is brucellosis. The bacteria that cause brucellosis belong to the genus Brucella. Numerous animal and human species are affected by brucellosis, with an estimated 500,000 human cases recorded annually worldwide. The occurrence of new areas of infection and the resurgence of infection in already infected areas indicate how dynamically brucellosis is distributed throughout different geographic regions. Bacteria originate from the blood and are found in the reticuloendothelial system, the liver, the spleen, and numerous other locations, including the joints, kidneys, heart, and genital tract. Diagnosis of this disease can be done by bacterial isolation, molecular tests, modified acid-fast stain, rose bengal test (RBT), milk ring test, complement fixation test, enzyme-linked immunosorbent assay, and serum agglutination test. The primary sign of a Brucella abortus infection is infertility, which can result in abortion and the birth of a frail fetus that may go on to infect other animals. In humans, the main symptoms are acute febrile illness, with or without localization signs, and chronic infection. Female cattle have a greater risk of contracting Brucella disease. Human populations at high risk of contracting brucellosis include those who care for cattle, veterinarians, slaughterhouse employees, and butchers. Antibiotic treatment of brucellosis is often unsuccessful due to the intracellular survival of Brucella and its adaptability in macrophages. A "one health" strategy is necessary to control illnesses like brucellosis.


Assuntos
Brucelose , Zoonoses , Brucelose/veterinária , Brucelose/epidemiologia , Brucelose/microbiologia , Brucelose/diagnóstico , Animais , Zoonoses/microbiologia , Humanos , Brucella/isolamento & purificação , Bovinos , Saúde Global
5.
PLoS Negl Trop Dis ; 18(6): e0011978, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38905305

RESUMO

BACKGROUND: Febrile illnesses that persist despite initial treatment are common clinical challenges in (sub)tropical low-resource settings. Our aim is to review infectious etiologies of "prolonged fevers" (persistent febrile illnesses, PFI) and to quantify relative contributions of selected neglected target diseases with limited diagnostic options, often overlooked, causing inadequate antibiotic prescriptions, or requiring prolonged and potentially toxic treatments. METHODS: We performed a systematic review of articles addressing the infectious etiologies of PFI in adults and children in sub-/tropical low- and middle-income countries (LMICs) using the PRISMA guidelines. A list of target diseases, including neglected parasites and zoonotic bacteria (e.g., Leishmania and Brucella), were identified by infectious diseases and tropical medicine specialists and prioritized in the search. Malaria and tuberculosis (TB) were not included as target diseases due to well-established epidemiology and diagnostic options. Four co-investigators independently extracted data from the identified articles while assessing for risk of bias. RESULTS: 196 articles from 52 countries were included, 117 from Africa (33 countries), 71 from Asia (16 countries), and 8 from Central and -South America (3 countries). Target diseases were reported as the cause of PFI in almost half of the articles, most frequently rickettsioses (including scrub typhus), relapsing fever borreliosis (RF-borreliosis), brucellosis, enteric fever, leptospirosis, Q fever and leishmaniasis. Among those, RF-borreliosis was by far the most frequently reported disease in Africa, particularly in Eastern Africa. Rickettsioses (including scrub typhus) were often described in both Africa and Asia. Leishmaniasis, toxoplasmosis and amoebiasis were the most frequent parasitic etiologies. Non-target diseases and non-tropical organisms (Streptococcus pneumoniae, Escherichia coli, and non-typhoidal Salmonella spp) were documented in a fifth of articles. CONCLUSIONS: Clinicians faced with PFI in sub-/tropical LMICs should consider a wide differential diagnosis including enteric fever and zoonotic bacterial diseases (e.g., rickettsiosis, RF-borreliosis and brucellosis), or parasite infections (e.g., leishmaniasis) depending on geography and syndromes. In the absence of adequate diagnostic capacity, a trial of antibiotics targeting relevant intra-cellular bacteria, such as doxycycline or azithromycin, may be considered.


Assuntos
Febre , Doenças Negligenciadas , Humanos , Doenças Negligenciadas/epidemiologia , Febre/etiologia , Febre/epidemiologia , Clima Tropical , África/epidemiologia , Animais , Brucelose/epidemiologia , Brucelose/complicações , Brucelose/diagnóstico
6.
J Orthop Surg Res ; 19(1): 378, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937747

RESUMO

BACKGROUND: The incidence of cervical spinal brucellosis is low, only a few case reports have been published, and case series are not widely reported in the medical literature. Therefore, clinical features, management, and outcomes of cervical spinal brucellosis are relatively unknown. In this series, the authors report 15 cases of patients with cervical spinal brucellosis, including clinical characteristic, imaging findings, management plans, the institution's experience, and outcomes at 1 year postoperatively. METHODS: The study reviewed the clinical and radiographic records of 15 patients who received antimicrobial pharmacotherapy, and anterior cervical debridement and fusion for cervical spinal brucellosis. The data collected included patient demographic characteristics, spinal level affected, abscess, neurology, pathological reports, duration and type of antimicrobial regimens, details of orthopedic management, and complications incurred during the procedure. RESULTS: Neck pain (100%) and limb paralysis (86.7%) were the most common clinical presentations, and the disease had a rapid progression. The C6-7 segment was the most commonly affected segment, followed by C4-5 and C5-6. Imaging commonly revealed epidural or paravertebral abscesses (80%). There was a significant improvement in the VAS, JOA, and NDI scores three months after surgery, and the scores continued to improve until the final follow-up. There was a statistically significant difference between the pre- and postoperative scores (P < 0.05). The ESR and CRP levels returned to normal within three months postoperatively, being 7.7 ± 4.5 mm/h and 7.55 ± 3.48 mg/L, respectively. There were statistically significant differences between the pre- and postoperative levels (P < 0.05). The positive rate of bacterial culture testing of pus or lesion tissues was only 40%, but blood cultures revealed an even lower positivity rate (33.3%). The average antimicrobial pharmacotherapy regimen duration was 6.1 ± 1.9 months. All patients achieved intervertebral bone fusion within 8 months (4.8 ± 1.4 months) after surgery and were cured with non-recurrence. CONCLUSIONS: Spinal brucellosis rarely affects the cervical region, but its impact is more dangerous due to potential complications such as paraplegia or tetraplegia arising from epidural abscesses that compress the spinal cord. Surgical debridement, along with essential antimicrobial therapy, is an effective strategy and can lead to satisfactory prognosis in managing cervical spinal brucellosis.


Assuntos
Brucelose , Vértebras Cervicais , Humanos , Masculino , Brucelose/cirurgia , Brucelose/complicações , Brucelose/tratamento farmacológico , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Adulto , Vértebras Cervicais/cirurgia , Vértebras Cervicais/diagnóstico por imagem , Seguimentos , Resultado do Tratamento , Idoso , Fusão Vertebral/métodos , Fusão Vertebral/efeitos adversos , Desbridamento/métodos , Estudos de Coortes , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Fatores de Tempo
7.
BMJ Case Rep ; 17(6)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38901850

RESUMO

We describe a case of brucellosis in a man in his 20s, who presented to the emergency department with a 1-month history of fevers, dry cough and knee pain. Blood cultures were positive after 55 hours and Ochrobactrum daejeonense was identified on matrix-assisted laser desorption/ionisation time of flight (MALDI-TOF) mass spectrometry. Ochrobactrum spp are Gram-negative organisms that are phylogenetically related to Brucella spp but commercially available MALDI-TOF libraries cannot distinguish between the two genera. Further positive blood cultures for O. daejeonense combined with characteristic growth patterns for Brucella spp led to targeted questioning of the patient regarding potential exposure risks, which revealed a history of consumption of unpasteurised camel milk in the Middle East 3 months earlier. Treatment of brucellosis was initiated and subsequent whole genome sequencing identified the blood culture isolate as Brucella melitensis confirming the diagnosis of brucellosis. This case highlights the challenges in the diagnosis of brucellosis in low-incidence settings.


Assuntos
Brucella melitensis , Brucelose , Ochrobactrum , Humanos , Brucella melitensis/isolamento & purificação , Brucella melitensis/genética , Masculino , Brucelose/diagnóstico , Brucelose/tratamento farmacológico , Brucelose/microbiologia , Ochrobactrum/genética , Ochrobactrum/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Antibacterianos/uso terapêutico , Adulto Jovem , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/microbiologia , Erros de Diagnóstico
8.
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
9.
Nanotechnology ; 35(39)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38917779

RESUMO

Safe and effective vaccine candidates are needed to address the limitations of existing vaccines against Brucellosis, a disease responsible for substantial economic losses in livestock. The present study aimed to encapsulate recombinant Omp25 and EipB proteins, knowledged antigen properties, into PLGA nanoparticles, characterize synthesized nanoparticles with different methods, and assessed theirin vitro/in vivoimmunostimulatory activities to develop new vaccine candidates. The recombinant Omp25 and EipB proteins produced with recombinant DNA technology were encapsulated into PLGA nanoparticles by double emulsion solvent evaporation technique. The nanoparticles were characterized using FE-SEM, Zeta-sizer, and FT-IR instruments to determine size, morphology, zeta potentials, and polydispersity index values, as well as to analyze functional groups chemically. Additionally, the release profiles and encapsulation efficiencies were assessed using UV-Vis spectroscopy. After loading with recombinant proteins, O-NPs reached sizes of 221.2 ± 5.21 nm, while E-NPs reached sizes of 274.4 ± 9.51 nm. The cumulative release rates of the antigens, monitored until the end of day 14, were determined to be 90.39% for O-NPs and 56.1% for E-NPs. Following the assessment of thein vitrocytotoxicity and immunostimulatory effects of both proteins and nanoparticles on the J774 murine macrophage cells,in vivoimmunization experiments were conducted using concentrations of 16µg ml-1for each protein. Both free antigens and antigen-containing nanoparticles excessively induced humoral immunity by increasing producedBrucella-specific IgG antibody levels for 3 times in contrast to control. Furthermore, it was also demonstrated that vaccine candidates stimulated Th1-mediated cellular immunity as well since they significantly raised IFN-gamma and IL-12 cytokine levels in murine splenocytes rather than IL-4 following to immunization. Additionally, the vaccine candidates conferred higher than 90% protection from the infection according to challenge results. Our findings reveal that PLGA nanoparticles constructed with the encapsulation of recombinant Omp25 or EipB proteins possess great potential to triggerBrucella-specific humoral and cellular immune response.


Assuntos
Brucelose , Nanopartículas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Proteínas Recombinantes , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Brucelose/prevenção & controle , Brucelose/imunologia , Camundongos , Nanopartículas/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/química , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/química , Camundongos Endogâmicos BALB C , Feminino , Vacina contra Brucelose/imunologia , Vacina contra Brucelose/genética , Vacina contra Brucelose/administração & dosagem , Brucella abortus/imunologia , Brucella abortus/genética , Portadores de Fármacos/química , Nanovacinas
10.
Surgery ; 176(2): 531-534, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38839433

RESUMO

We aimed to analyze the feasibility of endovascular treatment for brucellosis-related aorta-iliac artery pseudoaneurysm. We did a statistical analysis that among the 11 cases, the thoracic aorta was involved in 3 cases, the abdominal aorta was involved in 6 cases, and the iliac artery was involved in 2 cases. Five patients had a history of contact with cattle and sheep, 3 had a history of drinking raw milk, 10 patients had a fever before the operation, and 11 patients had positive serum agglutination test. Blood culture was positive in 2 patients. All patients were given anti-brucellosis treatment immediately after diagnosis. One died of aortic rupture 5 days after emergency endovascular gastrointestinal bleeding. Endovascular-covered stent implantation and active anti-brucellosis therapy were used to treat 10 patients. The follow-up period was 8 years without aortic complications or death for all patients. We think early diagnosis and a combination of anti-brucellosis drugs and endovascular therapy may be the first choice for treating the pseudoaneurysm caused by Brucella.


Assuntos
Falso Aneurisma , Brucelose , Procedimentos Endovasculares , Humanos , Falso Aneurisma/terapia , Falso Aneurisma/microbiologia , Falso Aneurisma/etiologia , Falso Aneurisma/diagnóstico , Brucelose/complicações , Brucelose/diagnóstico , Masculino , Procedimentos Endovasculares/métodos , Feminino , Pessoa de Meia-Idade , Adulto , Stents , Idoso , Aneurisma Infectado/microbiologia , Aneurisma Infectado/diagnóstico , Aneurisma Infectado/terapia , Artéria Ilíaca/cirurgia , Aneurisma Ilíaco/microbiologia , Aneurisma Ilíaco/cirurgia , Aneurisma Ilíaco/terapia , Aneurisma Ilíaco/diagnóstico por imagem , Antibacterianos/uso terapêutico , Resultado do Tratamento , Estudos Retrospectivos
11.
Int Immunopharmacol ; 137: 112443, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38897124

RESUMO

Brucella is an intracellular parasitic bacterium lacking typical virulence factors, and its pathogenicity primarily relies on replication within host cells. In this study, we observed a significant increase in spleen weight in mice immunized with a Brucella strain deleted of the gene for alanine racemase (Alr), the enzyme responsible for alanine racemization (Δalr). However, the bacterial load in the spleen markedly decreased in the mutant strain. Concurrently, the ratio of white pulp to red pulp in the spleen was increased, serum IgG levels were elevated, but no significant damage to other organs was observed. In addition, the inflammatory response was potentiated and the NF-κB-NLRP3 signaling pathway was activated in macrophages (RAW264.7 Cells and Bone Marrow-Derived Cells) infect ed with the Δalr mutant. Further investigation revealed that the Δalr mutant released substantial amounts of protein in a simulated intracellular environment which resulted in heightened inflammation and activation of the TLR4-NF-κB-NLRP3 pathway in macrophages. The consequent cytoplasmic exocytosis reduced intracellular Brucella survival. In summary, cytoplasmic exocytosis products resulting from infection with a Brucella strain deleted of the alr gene effectively activated the TLR4-NFκB-NLRP3 pathway, triggered a robust inflammatory response, and reduced bacterial survival within host cells. Moreover, the Δalr strain exhibits lower toxicity and stronger immunogenicity in mice.


Assuntos
Brucella suis , Brucelose , Macrófagos , NF-kappa B , Proteína 3 que Contém Domínio de Pirina da Família NLR , Receptor 4 Toll-Like , Animais , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , NF-kappa B/metabolismo , Brucelose/imunologia , Brucelose/microbiologia , Brucelose/genética , Células RAW 264.7 , Brucella suis/imunologia , Brucella suis/genética , Brucella suis/patogenicidade , Virulência/genética , Macrófagos/imunologia , Deleção de Genes , Transdução de Sinais/imunologia , Feminino , Camundongos Endogâmicos BALB C , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Baço/imunologia , Inflamação/imunologia
13.
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
14.
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
15.
Res Vet Sci ; 176: 105339, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38941712

RESUMO

Brucellosis, caused by various Brucella species, poses a significant threat to global public health and livestock industries. This study aims to fill the knowledge gap concerning the presence of Brucella spp. in rodents on livestock farms in Iran. Both bacteriological and molecular surveys were conducted to assess the prevalence of Brucella spp. in these rodent populations. A total of 16 rodents were captured in four seropositive dairy cattle farms (n = 7) and two seropositive sheep farms (n = 9) and were then examined for the presence of the Brucella-infection. Five cow milk samples and 53 bovine lymph node samples from these farms were also tested for Brucella spp. Lymph node samples from dairy cattle farms contained 32 B. abortus biovar 3 isolates and one B. melitensis Rev1 vaccine isolate. The bacterial culture of rodents identified 12.5% of them (Mus musculus and Rattus norvegicus) harboring Brucella strains in dairy cattle farms. The rodents had B. abortus biovar 3 and B. melitensis biovar 1, suggesting a reservoir for these bacteria. A two-step molecular assay, utilizing the Omp28 sequences in tissue samples of rodents, demonstrated that 68.75% (n = 11) of the tested rodents yielded positive results. Bruce-ladder PCR and wboA typing on isolated bacteria revealed a close relationship to field strain of Brucella species. The study reveals that rodents on seropositive livestock farms in Iran harbor Brucella spp., indicating a potential reservoir for these bacteria. This highlights the importance of monitoring rodent populations through the molecular and bacterial methods to manage and control brucellosis in livestock.


Assuntos
Brucella , Brucelose , Animais , Bovinos , Irã (Geográfico)/epidemiologia , Ratos , Brucella/isolamento & purificação , Brucella/classificação , Ovinos , Brucelose/veterinária , Brucelose/epidemiologia , Brucelose/microbiologia , Camundongos , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/epidemiologia , Prevalência , Brucelose Bovina/epidemiologia , Brucelose Bovina/microbiologia , Leite/microbiologia , Brucella abortus/isolamento & purificação , Brucella abortus/classificação , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/microbiologia , Feminino
16.
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
17.
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
18.
BMC Infect Dis ; 24(1): 489, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741035

RESUMO

BACKGROUND: It is challenging to diagnose brucellosis in nonendemic regions because it is a nonspecific febrile disease. The accurate identification of Brucella spp. in clinical microbiology laboratories (CMLs) continues to pose difficulties. Most reports of misidentification are for B. melitensis, and we report a rare case of misidentified B. abortus. CASE PRESENTATION: A 67-year-old man visited an outpatient clinic complaining of fatigue, fever, and weight loss. The patient had a history of slaughtering cows with brucellosis one year prior, and his Brucella antibody tests were negative twice. After blood culture, the administration of doxycycline and rifampin was initiated. The patient was hospitalized due to a positive blood culture. Gram-negative coccobacilli were detected in aerobic blood culture bottles, but the CML's lack of experience with Brucella prevented appropriate further testing. Inaccurate identification results were obtained for a GN ID card of VITEK 2 (bioMérieux, USA) and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) using a MALDI Biotyper (Bruker, Germany). The strain showed 100.0% identity with Brucella spp. according to 16S rRNA sequencing. MALDI-TOF MS peaks were reanalyzed using the CDC MicrobeNet database to determine Brucella spp. (score value: 2.023). The patient was discharged after nine days of hospitalization and improved after maintaining only doxycycline for six weeks. The isolate was also identified as Brucella abortus by genomic evidence. CONCLUSION: Automated identification instruments and MALDI-TOF MS are widely used to identify bacteria in CMLs, but there are limitations in accurately identifying Brucella spp. It is important for CMLs to be aware of the possibility of brucellosis through communication with clinicians. Performing an analysis with an additional well-curated MALDI-TOF MS database such as Bruker security-relevant (SR) database or CDC MicrobeNet database is helpful for quickly identifying the genus Brucella.


Assuntos
Bacteriemia , Brucella abortus , Brucelose , Idoso , Humanos , Masculino , Brucelose/diagnóstico , Brucelose/microbiologia , Brucelose/tratamento farmacológico , Brucella abortus/isolamento & purificação , Brucella abortus/genética , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Bacteriemia/tratamento farmacológico , Diagnóstico Tardio , Antibacterianos/uso terapêutico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Animais
19.
Sci Rep ; 14(1): 11951, 2024 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-38789443

RESUMO

Brucellosis is a zoonotic disease with significant economic and healthcare costs. Despite the eradication efforts, the disease persists. Vaccines prevent disease in animals while antibiotics cure humans with limitations. This study aims to design vaccines and drugs for brucellosis in animals and humans, using protein modeling, epitope prediction, and molecular docking of the target proteins (BvrR, OMP25, and OMP31). Tertiary structure models of three target proteins were constructed and assessed using RMSD, TM-score, C-score, Z-score, and ERRAT. The best models selected from AlphaFold and I-TASSER due to their superior performance according to CASP 12 - CASP 15 were chosen for further analysis. The motif analysis of best models using MotifFinder revealed two, five, and five protein binding motifs, however, the Motif Scan identified seven, six, and eight Post-Translational Modification sites (PTMs) in the BvrR, OMP25, and OMP31 proteins, respectively. Dominant B cell epitopes were predicted at (44-63, 85-93, 126-137, 193-205, and 208-237), (26-46, 52-71, 98-114, 142-155, and 183-200), and (29-45, 58-82, 119-142, 177-198, and 222-251) for the three target proteins. Additionally, cytotoxic T lymphocyte epitopes were detected at (173-181, 189-197, and 202-210), (61-69, 91-99, 159-167, and 181-189), and (3-11, 24-32, 167-175, and 216-224), while T helper lymphocyte epitopes were displayed at (39-53, 57-65, 150-158, 163-171), (79-87, 95-108, 115-123, 128-142, and 189-197), and (39-47, 109-123, 216-224, and 245-253), for the respective target protein. Furthermore, structure-based virtual screening of the ZINC and DrugBank databases using the docking MOE program was followed by ADMET analysis. The best five compounds of the ZINC database revealed docking scores ranged from (- 16.8744 to - 15.1922), (- 16.0424 to - 14.1645), and (- 14.7566 to - 13.3222) for the BvrR, OMP25, and OMP31, respectively. These compounds had good ADMET parameters and no cytotoxicity, while DrugBank compounds didn't meet Lipinski's rule criteria. Therefore, the five selected compounds from the ZINC20 databases may fulfill the pharmacokinetics and could be considered lead molecules for potentially inhibiting Brucella's proteins.


Assuntos
Brucella , Biologia Computacional , Simulação de Acoplamento Molecular , Biologia Computacional/métodos , Brucella/química , Brucella/imunologia , Brucella/metabolismo , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Humanos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito B/química , Brucelose/prevenção & controle , Brucelose/imunologia , Animais
20.
Epidemiol Infect ; 152: e88, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770575

RESUMO

Brucellosis, a global zoonosis, is endemic in Israel. We used a national database of culture-confirmed cases (2004-2022) to analyse the trends of brucellosis. Of 2,489 unique cases, 99.8% were bacteraemic, 64% involved males, and the mean age was 30.5 years. Brucella melitensis was the dominant species (99.6%). Most cases occurred among the Arab sector (84.9%) followed by the Jewish (8.5%) and Druze (5.5%) sectors. The average annual incidence rates overall and for the Arab, Druze, and Jewish sectors were 1.6/100,000, 6.6/100,000, 5.5/100,000, and 0.18/100,000, respectively. The annual incidence rates among the Arab (incidence rate ratio (IRR) = 36.4) and the Druze (IRR = 29.6) sectors were significantly higher than among the Jewish sector (p < 0.001). The highest incidence rates among the Arab sector occurred in the South District, peaking at 41.0/100,000 in 2012. The frequencies of B. melitensis isolated biotypes (biotype 1 - 69.1%, biotype 2 - 26.0%, and biotype 3 - 4.3%) differed from most Middle Eastern and European countries. A significant switch between the dominant biotypes was noted in the second half of the study period. Efforts for control and prevention should be sustained and guided by a One Health approach mindful of the differential trends and changing epidemiology.


Assuntos
Brucelose , Israel/epidemiologia , Brucelose/epidemiologia , Brucelose/microbiologia , Humanos , Masculino , Feminino , Incidência , Adulto , Pessoa de Meia-Idade , Adolescente , Criança , Adulto Jovem , Idoso , Pré-Escolar , Lactente , Idoso de 80 Anos ou mais , Brucella melitensis/isolamento & purificação
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