Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 164
Filtrar
1.
Biomedica ; 44(2): 182-190, 2024 05 30.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-39088528

RESUMO

Introduction: The Mycobacterium chelonae species and the M. avium and M. abscessus complexes are emerging pathogens that cause mycobacteriosis. Treatment depends on the species and subspecies identified. The drugs of choice are macrolides and aminoglycosides. However, due to the resistance identified to these drugs, determining the microbe's sensitivity profile will allow clinicians to improve the understanding of the prognosis and evolution of these pathologies. Objective: To describe the macrolide and aminoglycoside susceptibility profile of cultures identified by Colombia's Laboratorio Nacional de Referencia de Mycobacteria from 2018 to 2022, as Mycobacterium avium complex, M. abscessus complex, and M. chelonae. Materials and methods. This descriptive study exposes the susceptibility profile to macrolides and aminoglycosides of cultures identified as M. avium complex, M. abscessus complex, and M. chelonae using the GenoType® NTM-DR method. Materials and methods: This descriptive study exposes the susceptibility profile to macrolides and aminoglycosides of cultures identified as M. avium complex, M. abscessus complex, and M. chelonae using the GenoType® NTM-DR method. Results: We identified 159 (47.3 %) cultures as M. avium complex, of which 154 (96.9 %) were sensitive to macrolides, and 5 (3.1 %) were resistant; all were sensitive to aminoglycosides. From the 125 (37.2 %) cultures identified as M. abscessus complex, 68 (54.4 %) were sensitive to macrolides, 57 (45.6 %) were resistant to aminoglycosides, and just one (0.8 %) showed resistance to aminoglycosides. The 52 cultures (15.5 %) identified as M. chelonae were sensitive to macrolides and aminoglycosides. Conclusions: The three studied species of mycobacteria have the least resistance to Amikacin. Subspecies identification and their susceptibility profiles allow the establishment of appropriate treatment schemes, especially against M. abscessus.


Introducción. Mycobacterium chelonae y los complejos Mycobacterium avium y M. abscessus, son agentes patógenos emergentes causantes de micobacteriosis. El tratamiento de esta infección depende de la especie y la subespecie identificadas. Los fármacos de elección son los macrólidos y aminoglucósidos, contra los cuales se ha reportado resistencia; por esta razón, el determinar el perfil de sensibilidad le permite al médico tratante comprender mejor el pronóstico y la evolución de estas infecciones. Objetivo. Describir los perfiles de sensibilidad ante macrólidos y aminoglucósidos, de los cultivos identificados como complejo Mycobacterium avium, complejo M. abscessus o especie M. chelonae, en el Laboratorio Nacional de Referencia de Micobacterias durante los años 2018 a 2022. Materiales y métodos. Se llevó a cabo un estudio descriptivo del perfil de sensibilidad a macrólidos y aminoglucósidos, de los cultivos identificados como complejo M. avium, complejo M. abscessus o M. chelonae, mediante la metodología GenoType® NTM-DR. Resultados. Los cultivos del complejo M. avium fueron 159 (47,3 %), de los cuales, 154 (96,9 %) fueron sensibles y 5 (3,1 %) resistentes a los macrólidos; todos fueron sensibles a los aminoglucósidos. Del complejo M. abscessus se estudiaron 125 (37,2 %) cultivos, 68 (54,4 %) resultaron sensibles y 57 (45,6 %) resistentes a los macrólidos; solo un cultivo (0,8 %) fue resistente a los aminoglucósidos. De M. chelonae se analizaron 52 cultivos (15,5 %), todos sensibles a los macrólidos y aminoglucósidos. Conclusiones. En las tres especies de micobacterias estudiadas, la resistencia contra la amikacina fue la menos frecuente. La identificación de las subespecies y los perfiles de sensibilidad permiten instaurar esquemas de tratamiento adecuados, especialmente en las micobacteriosis causadas por M. abscessus.


Assuntos
Aminoglicosídeos , Macrolídeos , Testes de Sensibilidade Microbiana , Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Complexo Mycobacterium avium , Mycobacterium chelonae , Macrolídeos/farmacologia , Mycobacterium abscessus/efeitos dos fármacos , Mycobacterium abscessus/genética , Mycobacterium abscessus/isolamento & purificação , Colômbia/epidemiologia , Mycobacterium chelonae/efeitos dos fármacos , Mycobacterium chelonae/genética , Mycobacterium chelonae/isolamento & purificação , Aminoglicosídeos/farmacologia , Humanos , Complexo Mycobacterium avium/efeitos dos fármacos , Complexo Mycobacterium avium/genética , Complexo Mycobacterium avium/isolamento & purificação , Infecções por Mycobacterium não Tuberculosas/microbiologia , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Prevalência , Farmacorresistência Bacteriana Múltipla
2.
Vaccine ; 42(23): 126055, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-38880691

RESUMO

Vaccination is the best strategy to control Paratuberculosis (PTB), which is a significant disease in cattle and sheep. Previously we showed the humoral and cellular immune response induced by a novel vaccine candidate against PTB based on the Argentinian Mycobacterium avium subspecies paratuberculosis (Map) 6611 strain. To improve 6611 immunogenicity and efficacy, we evaluated this vaccine candidate in mice with two different adjuvants and a heterologous boost with a recombinant modified vaccinia Ankara virus (MVA) expressing the antigen 85A (MVA85A). We observed that boosting with MVA85A did not improve total IgG or specific isotypes in serum induced by one or two doses of 6611 formulated with incomplete Freund's adjuvant (IFA). However, when 6611 was formulated with ISA201 adjuvant, MVA85A boost enhanced the production of IFNγ, Th1/Th17 cytokines (IL-2, TNF, IL-17A) and IL-6, IL-4 and IL-10. Also, this group showed the highest levels of IgG2b and IgG3 isotypes, both important for better protection against Map infection in the murine model. Finally, the heterologous scheme elicited the highest levels of protection after Map challenge (lowest CFU count and liver lesion score). In conclusion, our results encourage further evaluation of 6611 strain + ISA201 prime and MVA85A boost in bovines.


Assuntos
Adjuvantes Imunológicos , Anticorpos Antibacterianos , Citocinas , Modelos Animais de Doenças , Imunização Secundária , Imunoglobulina G , Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Animais , Mycobacterium avium subsp. paratuberculosis/imunologia , Imunização Secundária/métodos , Camundongos , Paratuberculose/prevenção & controle , Paratuberculose/imunologia , Imunoglobulina G/sangue , Citocinas/metabolismo , Feminino , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Adjuvantes Imunológicos/administração & dosagem , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Camundongos Endogâmicos BALB C , Vaccinia virus/imunologia , Vaccinia virus/genética , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/genética , Imunidade Celular/imunologia , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Adjuvante de Freund/administração & dosagem , Adjuvante de Freund/imunologia
3.
Vet Res Commun ; 48(4): 2645-2650, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38575801

RESUMO

Mycobacterium avium subsp. paratuberculosis (MAP) is the causal agent of paratuberculosis (PTBC), a chronic infectious granulomatous enteritis of ruminants. The PTBC diagnosis with commercial ELISA has limitations in sensitivity and specificity, and its results depend on the state of progress of the disease. This research aimed to evaluate two different ELISAs: (a) an "in-house" ELISA with a sonicated antigen obtained from a MAP I47 strain, and (b) a commercial ELISA. In total, the evaluated sample consisted of 394 bovine serum samples from 12 farms in Argentina with high (5-9%) and low (≤ 0.05%) prevalence of PTBC. The evaluation of the new antigen (2.5 µg/mL) was against a 1:50 dilution of the M. phlei faced sera. The cut-off point, sensitivity, and specificity determinations of both techniques were by ROC curve analysis. The area under the curve for the I47 ELISA was 0.9 (CI 95%, 0.93-0.97). With a cut-off point of 8.8%, the sensitivity was 84.3% and the specificity 96.6%. The agreement between both techniques was 0.7 (CI 95%, 0.6-0.8). These results indicate a high discriminative capacity to differentiate positive and negative bovine sera of MAP infection with the I47 ELISA. This result would represent an advantage to dispense with the imported kit.


Assuntos
Doenças dos Bovinos , Ensaio de Imunoadsorção Enzimática , Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Sensibilidade e Especificidade , Bovinos , Animais , Paratuberculose/diagnóstico , Paratuberculose/sangue , Paratuberculose/microbiologia , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/sangue , Doenças dos Bovinos/microbiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Mycobacterium avium subsp. paratuberculosis/imunologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Testes Sorológicos/veterinária , Testes Sorológicos/métodos , Argentina
4.
Braz J Vet Med ; 46: e002723, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38282832

RESUMO

Analysis of the primary and recall responses to a membrane molecule (MMP), encoded by MAP2121c demonstrated that tri-directional signaling between the antigen-presenting cell (APC), CD4 and CD8 is essential for eliciting a CD8 cytotoxic T cell (CTL) response against Mycobacterium avium subsp. paratuberculosis. As reported here, RNA-sequencing was used to initiate the characterization of the signaling pathways involved in eliciting the development of CD8 CTL, starting with the characterization of the activation status of genes in monocyte-derived macrophages (MoMΦ) following uptake and processing MMP for the presentation of antigenic epitopes to CD4 and CD8 T cells. Activation status was compared with the uptake and processing of LPS, a nonspecific stimulator of macrophages. 1609 genes were identified that were upregulated, and 1277 were downregulated three hours after uptake and processing MMP. No significant difference was observed in the cytokine genes selected for analysis of the signaling that must occur between APC, CD4, and CD8 for the development of CTL. The initial observations indicate screening of the transcriptome should include genes involved in signaling between APC and CD4, and CD8 regardless of their activation status. Four genes of interest in this study, IL12A, IL12B, IL15, and IL23A, were not significantly different from control values. The initial studies also indicate MoMΦ can be included with dendritic cells and monocyte-derived dendritic cells for further analysis of the tri-directional signaling required for the development of CTL.


A análise das respostas primárias e de recall a uma molécula de membrana (MMP), codificada por MAP2121c demonstrou que a sinalização tridirecional entre a célula apresentadora de antígeno (APC), CD4 e CD8 é essencial para provocar uma resposta de células T citotóxicas CD8 (CTL) contra Mycobacterium avium subsp. paratuberculose. Conforme relatado aqui, o sequenciamento de RNA foi usado para iniciar a caracterização das vias de sinalização envolvidas na indução do desenvolvimento de CTL CD8, começando com a caracterização do status de ativação de genes em macrófagos derivados de monócitos (MoMΦ) após captação e processamento de MMP para a apresentação de epítopos antigênicos às células T CD4 e CD8. O status de ativação foi comparado com a captação e processamento de LPS, um estimulador inespecífico de macrófagos. Foram identificados 1.609 genes que foram regulados positivamente e 1.277 foram regulados negativamente três horas após a captação e processamento de MMP. Nenhuma diferença significativa foi observada nos genes de citocinas selecionados para análise da sinalização que deve ocorrer entre APC, CD4 e CD8 para o desenvolvimento de CTL. As observações iniciais indicam que o rastreio do transcriptoma deve incluir genes envolvidos na sinalização entre APC e CD4 e CD8, independentemente do seu estado de activação. Quatro genes de interesse neste estudo, IL12A, IL12B, IL15 e IL23A, não foram significativamente diferentes dos valores de controle. Os estudos iniciais também indicam que o MoMΦ pode ser incluído com células dendríticas e células dendríticas derivadas de monócitos para análise adicional da sinalização tridirecional necessária para o desenvolvimento de CTL.

5.
Immunobiology ; 228(4): 152416, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37429053

RESUMO

Mycobacterium avium (M. avium) represents a species of concern, because of its ability to modulate the host's innate immune response, and therefore influence trajectory of adaptative immunity. Since eradicative response against mycobacteria, and M. tuberculosis/M. avium, relies on peptides actively presented on a Major Histocompatibility complex-II (MHC-II) context, we assessed paradoxical stimulation of Dendritic Cell resulting on immature immunophenotype characterized by membrane minor increase of MHC-II and CD40 despite of high expression of the pro-inflammatory tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) in supernatants. Identification of M. avium leucine rich peptides forming short α-helices shutting down Type 1T helper (Th1), contribute to the understanding of immune evasion of an increasingly prevalent pathogen, and may provide a basis for future immunotherapy to infectious and non-infectious disease.


Assuntos
Mycobacterium avium , Mycobacterium tuberculosis , Interleucina-6 , Complexo Principal de Histocompatibilidade , Células Dendríticas
6.
Braz J Microbiol ; 54(3): 2521-2526, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37227627

RESUMO

Mycobacterium avium is a zoonotic pathogen associated with a wide range of pulmonary and extrapulmonary manifestations in a range of host species like humans, animals, and birds. The disease is more common in the avian population, and opportunistic infections have been reported in immune-compromised or debilitated animals and humans. This study reports the pathological and molecular identification of Mycobacterium avium causing avian mycobacteriosis in a loft of domestic pigeons (Columba livia var. domestica). Out of 30 pigeons aged 2-3 years, ten adult racing pigeons revealed a severe chronic and debilitating disease followed by death. The clinical signs included chronic emaciation, dullness, ruffled feathers, lameness, and greenish, watery diarrhea. Post-mortem examination of birds revealed multifocal gray- to yellow-colored raised nodules in the liver parenchyma, spleen, lungs, intestines, bone marrow, and joints. Avian mycobacteriosis was suspected based on the tissue impression smears stained by Ziehl-Neelsen staining. Histopathological examination also revealed multifocal granulomatous lesions in affected organs, which is characteristic of avian mycobacteriosis. The PCR analysis based on 16S rRNA, IS1245, and IS901 regions suggested the presence of Mycobacterium avium infection belonging to either subspecies avium or sylvaticum. This is the first detailed report of avian mycobacteriosis in pigeons from India, warranting a strict surveillance program to identify the carrier status of these microorganisms in the pigeons, which may prove a fatal zoonotic infection in humans.


Assuntos
Columbidae , Mycobacterium avium , Animais , Humanos , RNA Ribossômico 16S/genética , Mycobacterium avium/genética , Fígado/patologia , Pulmão
7.
Braz J Microbiol ; 54(1): 407-413, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36572823

RESUMO

Copper causes significant damage to the integrity of many bacteria, mainly at the DNA level, through its redox states, as well as its reactive oxygen species (ROS) generating capacity at the cellular level. But whether these mechanisms also apply to Mycobacterium avium subsp. paratuberculosis (MAP) is unknown. In the present study, we have evaluated whether copper ions produce damage at the DNA level of MAP, either through their redox states or through ROS production. MAP-spiked PBS was first supplemented with different copper chelators (2) and ROS antioxidants (3), followed by treatment with copper ions at 942 ppm. MAP DNA integrity (qPCR, magnetic phage separation) was then evaluated. We found that bathocuproine (BCS), as a chelator, and D-mannitol, as an antioxidant of hydroxyl radicals, had a significant protective effect (P < 0.05) on DNA molecules, and that EDTA, as a chelator, and D-mannitol, as an antioxidant had a significant positive effect (P < 0.05) on the viability of this pathogen in contrast to the control and other chelators and anti-oxidants used. In light of the reported findings, it may be concluded that copper ions within MAP cells are directly related to MAP DNA damage.


Assuntos
Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Animais , Mycobacterium avium subsp. paratuberculosis/genética , Paratuberculose/microbiologia , Cobre , Antioxidantes , Espécies Reativas de Oxigênio
8.
Microorganisms ; 10(11)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36422342

RESUMO

BACKGROUND: Mycobacterium avium subsp. paratuberculosis (MAP) is the causal agent of paratuberculosis. This pathogen is able to survive adverse environmental conditions, including the pasteurization process. Copper, a well-studied metal, is considered an important antibacterial tool, since it has been shown to inactivate even MAP in treated milk through unknown mechanisms. The aim of the present study is to show the effect of copper ions, and reactive oxygen species (ROS) generated in response to oxidative stress, on the damage to MAP DNA when exposed to a copper ion challenge in cow's milk. METHODOLOGY: Spiked milk with different MAP bacterial loads was supplemented with blocking agents. These were either the copper chelators ethylenediaminetetraacetic acid (EDTA) and batocuproin (BCS) or the ROS quenchers D-mannitol, gallic acid and quercetin. The DNA protection, MAP viability and ROS production generated after exposure to a copper challenge were then measured. RESULTS: In a bacterial load of 104 cells mL-1, blocking effects by both the copper chelators and all the ROS quenchers offered significant protection to MAP DNA. In a concentration of 102 cells mL-1, only D-mannitol and a mix of quenchers significantly protected the viability of the bacteria, and only at a concentration of 106 cells mL-1 was there a lower production of ROS when supplementing milk with gallic acid, quercetin and the mix of quenchers. CONCLUSION: Based on these findings, it may be concluded that MAP DNA damage can be attributed to the combined effect of the direct copper ions and ROS generated. Nevertheless, taking into account the antioxidant environment that milk provides, the direct effect of copper could play a prominent role.

9.
Braz J Microbiol ; 53(4): 2241-2249, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36251154

RESUMO

This study aimed to determine the presence of antibodies against Mycobacterium avium subspecies paratuberculosis (MAP) in high-producing dairy cows, the presence of the pathogen in the feces, and the risk factors associated with the disease. Blood and fecal samples were collected from 708 dairy cows over 2 years from 54 herds located in five municipalities of Paraná, Brazil. The serum samples were evaluated for the presence of antibodies against MAP using enzyme-linked immunosorbent assay (ELISA). Fecal samples from 100 cows (69 seropositive and 31 seronegative) were assessed using real-time PCR (qPCR) for IS900 of MAP. The herd prevalence of antibodies against MAP was 61.1% (33/54; 95% CI 46.88-74.08), ranging from 12.5 to 80% across the municipalities, and the prevalence in the animals was 9.8% (69/708; 95% CI 7.77-12.15); it ranged from 0 to 87.5% per herd. Only one of the 69 (1.45%) fecal samples from the seropositive cows was positive for the qPCR. The factors associated with the occurrence of paratuberculosis in herds were the use of compost barn system and the type of bed, whereas only the type of bed was associated with the infection of cows. The only risk factor (OR = 2.45; 95% CI 1.03-5.85) associated with the occurrence of paratuberculosis was the introduction of animals purchased from other dairy farms. The prevalence of active infection was low; however, our results demonstrate the presence of MAP in high-producing dairy herds in Paraná state, Brazil.


Assuntos
Doenças dos Bovinos , Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Feminino , Bovinos , Animais , Mycobacterium avium subsp. paratuberculosis/genética , Paratuberculose/epidemiologia , Paratuberculose/microbiologia , Brasil/epidemiologia , Doenças dos Bovinos/microbiologia , Ensaio de Imunoadsorção Enzimática/métodos , Fezes/microbiologia , Anticorpos Antibacterianos , Prevalência
10.
Top Companion Anim Med ; 51: 100698, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35985408

RESUMO

Environmental mycobacteria such as those from the Mycobacterium avium-intacellulare complex may cause disseminated and severe disease in dogs with genetic predisposition. A series of cases of 4 miniature schnauzers with nonspecific clinical signs and the diagnostic tests are described. Complementary means of diagnosis including complete blood count, biochemical serum analyses and fine needle aspiration cytology staining were performed. The bacteriological culture followed by PCR amplification of 1245 and 901 insertion sequences, allowed the identification of Mycobacterium avium subsp. hominissuis. This environmental Mycobacteria normally do not cause severe disease in dogs or other species, but when CARD-9 gene presents mutations, dogs may become extremely susceptible and disease is fast, disseminated, and fatal. Antibiotic therapy can be applied under veterinary consideration in specific situations, as treatment is usually applied for a long period of time. Although zoonotic risk is low as the Mycobacterium is environmental, contamination of the location may be high, and immunosuppressed animals and humans can develop infection as well. This report may aid clinical veterinarians in the diagnosis, treatment, and prognosis in similar cases of this breed and others with the genetic predisposition.


Assuntos
Doenças do Cão , Infecções por Mycobacterium , Cães , Animais , Humanos , Mycobacterium avium/genética , Argentina , Predisposição Genética para Doença , Complexo Mycobacterium avium/genética , Infecções por Mycobacterium/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/tratamento farmacológico
11.
Pathogens ; 11(2)2022 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35215214

RESUMO

BACKGROUND: Scientific evidence is scarce for the antimicrobial effect of copper on bacteria characterized as more resistant. Using Mycobacterium avium subsp. paratuberculosis (MAP), a highly resistant microorganism, as a pathogen model, copper ion treatment has shown a significant bactericidal effect; however, the sustainability of MAP against copper toxicity was also reported in several studies. Accordingly, the present study aimed to evaluate the impacts of copper on MAP. METHODOLOGY: This study considered physicochemical properties and copper concentration in a buffer since it could modulate MAP response during the application of copper treatment. RESULTS: Despite the efficacy of copper ions in significantly reducing the MAP load in Phosphate Buffered Saline, some MAP cells were able to survive. The copper concentration generated by the copper ion treatment device increased significantly with increasing exposure times. MAP bacterial load decreased significantly when treated with copper ions as the exposure times increased. An increase in pH decreased oxygen consumption, and an increase in conductivity was reported after treatment application. CONCLUSIONS: Even with higher concentrations of copper, the efficacy of MAP control was not complete. The concentration of copper must be a key element in achieving control of highly resistant microorganisms.

12.
Acta sci. vet. (Online) ; 50(suppl.1): Pub. 748, Feb. 6, 2022. mapas
Artigo em Inglês | VETINDEX | ID: vti-765207

RESUMO

Background: Mycobacteriosis is caused by bacteria belonging to the genus Mycobacterium, with considerable zoonoticpotential and risk to public health. Infection in dogs is rare and is usually associated with immunosuppression, resultingfrom eating meat or contact with contaminated soil or fomites. Dogs are also known as potential sources for the spread ofatypical tuberculosis in humans and other animals. This paper aims to describe the clinical, cytological, histopathological,and molecular findings of a male canine seen at University Veterinary Hospital of Cuiabá, Mato Grosso, with generalizedlymphadenomegaly associated Mycobacterium intracellulare infection.Case: A 2-year-old male Lhasa Apso dog was referred to the University Veterinary Hospital in Cuiabá city, located in theMidwest region of Brazil. The patient had a history of intermittent claudication of the left pelvic limb for approximately6 months and lymphadenomegaly with progression for approximately 2 months. The dog had wheezing and generalizedlymphadenopathy (submandibular, axillary, and popliteal lymph nodes); cryptorchidism was also observed. A completeblood count revealed nonspecific results, and in the serum biochemical profile, the values of urea, creatinine, albumin, andalanine aminotransferase were within the reference range. No changes were observed on the radiography of the femurotibiopatellar joints. Considering the generalised lymphadenopathy, fine needle aspiration cytology and histopathologicalexamination through biopsy of the lymph nodes was performed. On the cytology and histopathology, numerous negativeimages of moderately refringent bacillary structures distending the cytoplasm from the macrophages was found. Thesamples were also subjected to special Ziehl-Neelsen staining, which confirmed an accentuated and diffuse granulomatouslymphadenitis associated with alcohol...(AU)


Assuntos
Animais , Cães , Linfadenite/patologia , Linfadenite/veterinária , Infecção por Mycobacterium avium-intracellulare/complicações , Infecção por Mycobacterium avium-intracellulare/veterinária , Complexo Mycobacterium avium/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Infecções por Mycobacterium/veterinária
13.
Vet Immunol Immunopathol ; 245: 110381, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35033737

RESUMO

In this work, we used a calf ileal loop model to evaluate whether the preincubation of Mycobacterium avium subspecies paratuberculosis (MAP) with antibodies from healthy, MAP-positive or Lipoarabinomannan (LAM) immunized cows could affect the results of infection after 3.5 h. Bacterial load in tissue was assessed by Ziehl-Neelsen and by culture for each loop. MAP was detectable in all infected loops after 3.5 h.p.i.; although the presence of antibodies from MAP-positive cows significantly reduced bacterial load in loops as compared with antibodies from healthy donors (by Ziehl-Neelsen and culture, p-value < 0.003 and 0.0203, respectively). A possible direct effect of antibodies on MAP viability was shown to be not significant. Severity of histopathologic changes induced by MAP infection also varied according to the pretreatment: MAP induced less changes when inoculated in the presence of antibodies from MAP-positive cows as compared with antibodies from healthy donors. Overall, our results show that the presence of antibodies from MAP-positive cows reduced MAP invasion and consequent early histological changes in this ileal short-term loop model. These results may suggest a protective role of antibodies in the response against MAP at the portal of entry in cattle.


Assuntos
Doenças dos Bovinos , Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Animais , Anticorpos Antibacterianos , Bovinos , Fezes/microbiologia , Feminino
14.
Acta sci. vet. (Impr.) ; 50(suppl.1): Pub.748-4 jan. 2022. map
Artigo em Inglês | VETINDEX | ID: biblio-1458556

RESUMO

Background: Mycobacteriosis is caused by bacteria belonging to the genus Mycobacterium, with considerable zoonoticpotential and risk to public health. Infection in dogs is rare and is usually associated with immunosuppression, resultingfrom eating meat or contact with contaminated soil or fomites. Dogs are also known as potential sources for the spread ofatypical tuberculosis in humans and other animals. This paper aims to describe the clinical, cytological, histopathological,and molecular findings of a male canine seen at University Veterinary Hospital of Cuiabá, Mato Grosso, with generalizedlymphadenomegaly associated Mycobacterium intracellulare infection.Case: A 2-year-old male Lhasa Apso dog was referred to the University Veterinary Hospital in Cuiabá city, located in theMidwest region of Brazil. The patient had a history of intermittent claudication of the left pelvic limb for approximately6 months and lymphadenomegaly with progression for approximately 2 months. The dog had wheezing and generalizedlymphadenopathy (submandibular, axillary, and popliteal lymph nodes); cryptorchidism was also observed. A completeblood count revealed nonspecific results, and in the serum biochemical profile, the values of urea, creatinine, albumin, andalanine aminotransferase were within the reference range. No changes were observed on the radiography of the femurotibiopatellar joints. Considering the generalised lymphadenopathy, fine needle aspiration cytology and histopathologicalexamination through biopsy of the lymph nodes was performed. On the cytology and histopathology, numerous negativeimages of moderately refringent bacillary structures distending the cytoplasm from the macrophages was found. Thesamples were also subjected to special Ziehl-Neelsen staining, which confirmed an accentuated and diffuse granulomatouslymphadenitis associated with alcohol...


Assuntos
Animais , Cães , Complexo Mycobacterium avium/isolamento & purificação , Infecção por Mycobacterium avium-intracellulare/complicações , Infecção por Mycobacterium avium-intracellulare/veterinária , Linfadenite/patologia , Linfadenite/veterinária , Infecções por Mycobacterium/veterinária , Reação em Cadeia da Polimerase/veterinária
15.
Front Vet Sci ; 9: 962241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36713883

RESUMO

The objective was to evaluate the association between the severity of histopathological lesions caused by Mycobacterium avium subspecies paratuberculosis (MAP) infection and the molecular diversity of this pathogen. Blood, ileum, and mesenteric lymph node samples were collected at slaughter, from 1,352 adult cattle [source population 1 (SP1)]. In addition, 42 dairy herds (n = 4,963 cows) were followed for 2 years, and samples from compatible paratuberculosis clinical cases [source population 2 (SP2)] were collected. MAP infection was confirmed using an ELISA test, liquid media culture, and PCR. Isolates were genotyped using five MIRU-VNTR markers. Tissues from confirmed samples were subjected to a histopathological examination. A histopathological severity score (HSS) system was developed and used to grade (0 to 5) the magnitude of lesions caused by MAP. In general, the HSS system assesses the number of foci and degree of macrophage infiltration, together with the presence of multinucleated giant cells (MGCs) and acid-fast bacilli (AFB), in addition to the fusion of the intestinal villi and hyperplasia of the crypts. Despite the large sampling effort, only 79 MAP isolates were successfully genotyped, where 19 different haplotypes were described. A mixed-effect Poisson regression model was used to assess the relationship between haplotypes and HSS values. The model was controlled by animal age, and the farm was used as a random effect. Haplotypes were grouped based on their relative frequency: the most frequent haplotype (group i, 49.4%), the second most frequent haplotype (group ii, 12.7%), and all other haplotypes (group iii, 37.9%). Model outputs indicated that group i had significantly higher HSS values than group iii. In addition, group i was also associated with higher optical density (OD) values of the ELISA test. These results support the existence of differences in pathogenicity between MAP haplotypes. However, results were based on a relatively small sample size; thus, these should be taken with caution. Despite this, study findings suggest that haplotypes would be associated with differences in disease progression, where the dominant haplotype tends to generate more severe lesions, which could be linked to a greater shed of MAP cells than non-dominant haplotypes, increasing their chances of transmission.

16.
Res Vet Sci ; 138: 1-10, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34087563

RESUMO

The lprG-p55 operon of Mycobacterium tuberculosis, M. bovis and M. avium strain D4ER has been identified as a virulence factor involved in the transport of toxic compounds. LprG is a lipoprotein that modulates the host immune response against mycobacteria, whereas P55 is an efflux pump that provides resistance to several drugs. In the present study we search for, and characterize, lprg and p55, putative virulence genes in Mycobacterium avium subsp. paratuberculosis (MAP) to generate a live-attenuated strain of MAP that may be useful in the future as live-attenuated vaccine. For this purpose, we generated and evaluated two mutants of MAP strain K10: one mutant lacking the lprG gene (ΔlprG) and the other lacking both genes lprG and p55 (ΔlprG-p55). None of the mutant strains showed altered susceptibility to first-line and second-line antituberculosis drugs or ethidium bromide, only the double mutant had two-fold increase in clarithromycin susceptibility compared with the wild-type strain. The deletion of lprG and of lprG-p55 reduced the replication of MAP in bovine macrophages; however, only the mutant in lprG-p55 grew faster in liquid media and showed reduced viability in macrophages and in a mouse model. Considering that the deletion of both genes lprG-p55, but not that of lprG alone, showed a reduced replication in vivo, we can speculate that p55 contributes to the survival of MAP in this animal model.


Assuntos
Proteínas de Bactérias/genética , Deleção de Genes , Proteínas de Membrana Transportadoras/genética , Mycobacterium avium subsp. paratuberculosis/genética , Mycobacterium avium subsp. paratuberculosis/patogenicidade , Fatores de Virulência/genética , Animais , Proteínas de Bactérias/metabolismo , Bovinos , Feminino , Macrófagos/microbiologia , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Óperon , Virulência/genética , Fatores de Virulência/metabolismo
17.
Int J Mycobacteriol ; 10(1): 51-59, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33707372

RESUMO

Background: Paratuberculosis is an enteric disease caused by Mycobacterium avium sp. paratuberculosis (MAP) that affects mainly ruminant producing losses to the livestock industry. Many molecular epidemiological methods have been used to discriminate MAP isolates. Method: The aim of this study was to describe the genetic diversity of the Argentinean MAP isolates using a combination of two molecular systems, the mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) ("automated and "non-automated") and the multi-locus short-sequence repeat (MLSSR) system. Results: Thirty-two isolates were identified as MAP of C type by IS900 polymerase chain reaction (PCA) and IS1311 PCA-restriction enzyme analysis. The main patterns found by both MIRU-VNTR systems were INMV1 (54.5%), INMV2 (24.2%) and INMV11 (9.1%). The INMV5, INMV8 and INMV16 were represented with one isolate each (3.0%). Only 4 MIRU-VNTR loci were polymorphic. Conclusion: Those isolates sharing the same INMV patterns were analyzed by MLSSR, being locus 2 the most polymorphic one showing isolates with 9, 10, 11, and more than 11 "G" repeats. Besides, the global discriminatory power among isolates could be increased using both techniques. Based on these results, a short version of the "automated" MIRU-VNTR could be used as a screening tool to group isolates genetically related and subsequently perform the SSR using locus 2 on those isolates sharing the same INMV pattern.


Assuntos
Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Animais , Técnicas de Tipagem Bacteriana , Variação Genética , Genótipo , Humanos , Repetições Minissatélites , Mycobacterium avium subsp. paratuberculosis/genética , Paratuberculose/epidemiologia
18.
J Vet Diagn Invest ; 33(2): 375-378, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33525989

RESUMO

Johne's disease (paratuberculosis) is an economically important disease of cattle worldwide. The disease is caused by Mycobacterium avium subsp. paratuberculosis (MAP), a fastidious gram-positive bacterium. PCR is increasingly used in diagnostic laboratories for the detection of MAP in fecal samples given the rapid test turnaround time and sensitivity and specificity comparable to fecal culture. However, efficient extraction of DNA for sensitive detection of MAP by PCR is affected by the complex lipid-rich cell wall of MAP and the presence of PCR inhibitors in feces. We evaluated a high-throughput nucleic acid extraction method (MagMAX core nucleic acid purification kit with mechanical lysis module) in conjunction with an hspX gene PCR for the detection of MAP from bovine fecal samples, which resulted in correct identification of all negative (13 of 13) and positive (35 of 35) proficiency test samples obtained from the National Veterinary Services Laboratories. In addition, all 6 negative and 50 of 51 positive diagnostic specimens tested were categorized correctly.


Assuntos
Doenças dos Bovinos/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/diagnóstico , Reação em Cadeia da Polimerase/veterinária , Animais , Técnicas Bacteriológicas/métodos , Técnicas Bacteriológicas/veterinária , Bovinos , Fezes/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos
19.
Mol Biol Rep ; 48(1): 1025-1031, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33394225

RESUMO

Wild boars (Sus scrofa) are susceptible to mycobacterial infections, including tuberculous and non-tuberculous mycobacteria. Recently, Mycobacterium spp. infections were described in Brazilian wild boars, which can act as bacterial reservoirs. Here, we aim to characterize 15 Mycobacterium spp. isolates from Brazilian wild boars' tissues through partial sequencing of the heat shock protein 65 (hsp65) gene and phylogenetic analysis. The isolates were classified as M. tuberculosis (33.3%), M. colombiense (33.3%), M. avium subsp. hominissuis (13.3%), M. parmense (13.3%) and M. mantenii (6.66%). The isolates classified as M. tuberculosis were confirmed as variant bovis by PCR. At phylogenetic analysis some isolates formed separated clades, indicating genetic variability. Different Mycobacterium species were recovered from wild boars circulating in Brazil, including mycobacteria associated to zoonotic infections, such as M. tuberculosis. In addition, this is the first report in Brazilian wild boars on M. mantenii and M. parmense detection, two recently described pathogenic mycobacteria. However, the isolates' genetic diversity-i.e. identities lower than 100% when compared to reference sequences-suggests that other genotyping tools would allow a deeper characterization. Nonetheless, the reported data contributes to the knowledge on mycobacterial infections in wild boars from Brazil.


Assuntos
Mycobacterium tuberculosis/genética , Mycobacterium/genética , Doenças dos Suínos/epidemiologia , Tuberculose/veterinária , Animais , Brasil/epidemiologia , DNA Bacteriano/genética , Reservatórios de Doenças/microbiologia , Variação Genética , Humanos , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Análise de Sequência de DNA , Sus scrofa/microbiologia , Suínos , Doenças dos Suínos/microbiologia , Tuberculose/epidemiologia , Tuberculose/microbiologia
20.
J. bras. pneumol ; J. bras. pneumol;47(2): e20200520, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1250198

RESUMO

ABSTRACT Objective: Although Mycobacterium avium complex (MAC) lung disease has been shown to be associated with lung cancer and hematologic malignancies, there have been few studies of its relationships with other types of cancer. The aim of this study was to assess the effect that coexisting advanced extrapulmonary solid tumors have on the progression of MAC lung disease. Methods: This was a retrospective study of patients diagnosed with MAC lung disease, on the basis of the American Thoracic Society (ATS) criteria, between October of 2005 and March of 2019. The patients were divided into three groups: those with advanced-stage cancer (A-SC group); those with early-stage cancer (E-SC group); and those without cancer (control group). Progression of MAC lung disease was defined as exacerbation seen on imaging. Patient characteristics and the time to progression were compared among the three groups. Results: A total of 286 patients met the ATS diagnostic criteria for MAC lung disease, and 128 of those were excluded. Of the remaining 158 patients, 20 (7.0%) were in the A-SC group, 36 (12.6%) were in the E-SC group, and 102 (35.7%) were in the control group. The median time to progression in the A-SC, E-SC, and control groups was 432, 3,595, and 2,829 days, respectively (p < 0.01). A proportional hazards model showed that the significant predictors of MAC lung disease progression were advanced-stage cancer (hazard ratio [HR] = 6.096; 95% CI: 2.688-13.826; p < 0.01), cavitary lesions (HR = 2.750; 95% CI: 1.306-5.791; p < 0.01), and a high Nodule-Infiltration-Cavity-Ectasis score (HR = 1.046; 95% CI: 1.004-1.091; p = 0.033). Conclusions: A coexisting advanced extrapulmonary solid tumor could hasten the progression of MAC lung disease.


RESUMO Objetivo: Embora tenha sido demonstrado que a doença pulmonar por Mycobacterium avium complex (MAC, complexo M. avium) está associada a câncer de pulmão e neoplasias hematológicas, há poucos estudos sobre sua relação com outros tipos de câncer. O objetivo deste estudo foi avaliar o efeito da coexistência de tumores sólidos extrapulmonares avançados na progressão da doença pulmonar por MAC. Métodos: Estudo retrospectivo de pacientes diagnosticados com doença pulmonar por MAC, segundo os critérios da American Thoracic Society (ATS), entre outubro de 2005 e março de 2019. Os pacientes foram divididos em três grupos: grupo câncer em estágio avançado (grupo CEA), grupo câncer em estágio inicial (grupo CEI) e grupo sem câncer (grupo controle). Progressão da doença pulmonar por MAC foi definida como exacerbação observada em exame de imagem. As características dos pacientes e o tempo para progressão foram comparados entre os três grupos. Resultados: Um total de 286 pacientes preencheu os critérios diagnósticos da ATS para doença pulmonar por MAC, sendo 128 deles excluídos. Dos 158 pacientes restantes, 20 (7,0%) eram do grupo CEA, 36 (12,6%), do grupo CEI e 102 (35,7%), do grupo controle. A mediana de tempo para progressão nos grupos CEA, CEI e controle foi de 432, 3.595 e 2.829 dias, respectivamente (p < 0,01). Um modelo de riscos proporcionais demonstrou que os preditores significativos de progressão da doença pulmonar por MAC foram câncer em estágio avançado (razão de risco [RR] = 6,096; 95%IC: 2,688-13,826; p < 0,01), lesões cavitárias (RR = 2,750; 95%IC: 1,306-5,791; p < 0,01) e pontuação alta no sistema Nódulo-Infiltração-Cavidade-Ectasia (RR = 1,046; 95%IC: 1,004-1,091; p = 0,033). Conclusões: A coexistência de tumor sólido extrapulmonar avançado poderia acelerar a progressão da doença pulmonar por MAC.


Assuntos
Humanos , Infecção por Mycobacterium avium-intracellulare , Pneumopatias , Neoplasias , Complexo Mycobacterium avium , Estudos Retrospectivos , Pulmão
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA