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1.
Transbound Emerg Dis ; 68(2): 565-572, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32644252

RESUMO

Opossums of the genus Didelphis are considered synanthropic animals due to their close contact with human beings. Previously, two species of hemotropic mycoplasmas (hemoplasmas) have been detected in opossums: 'Candidatus Mycoplasma haemodidelphidis' in the North American opossum (Didelphis virginiana) and a potentially novel hemotropic Mycoplasma sp. in the white-eared opossums (Didelphis albiventris) from Brazil. Accordingly, the aims of this study were as follows: (a) to determine the prevalence of hemotropic Mycoplasma spp. in free-ranging opossums, (b) to characterize molecularly the hemotropic Mycoplasma sp. infecting opossums and (c) to determine factors associated with hemoplasma infection in opossums from Canoinhas municipality, Santa Catarina State, southern Brazil. For this purpose, 50 white-eared opossums (33 captured and 17 road-killed animals) were evaluated by a pan-hemoplasma PCR assay based on 16S rRNA. Six out of 50 (12%; 95% CI: 5.6%-23.8%) opossums were infested by Ctenocephalides felis fleas. Twenty out of 50 (40%; 95% CI: 26.41%-54.82%) opossums tested positive for hemotropic Mycoplasma sp. by PCR. Sequencing and phylogenetic analysis of the 16S and 23S rRNA gene fragments confirmed that animals were infected by a potentially novel hemotropic Mycoplasma sp. previously reported in white-eared opossums from Brazil. No significant association was found between gender (p = .7759), trap area (p = .0887) or presence of fleas (p = .3811) and positivity for hemoplasmas. The potentially novel hemoplasma species seems to be highly prevalent in white-eared opossums from the states of Paraná, Santa Catarina and Mato Grosso do Sul. Based on the phylogenetic analyses of the 16S rRNA and 23S rRNA genes along with epidemiological data, the name 'Candidatus Mycoplasma haemoalbiventris' is proposed for this novel organism.


Assuntos
Didelphis , Infecções por Mycoplasma/veterinária , Mycoplasma/fisiologia , Animais , Brasil/epidemiologia , Didelphis/microbiologia , Feminino , Masculino , Mycoplasma/classificação , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/microbiologia , Prevalência
2.
J Reprod Immunol ; 126: 60-68, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29524791

RESUMO

The polybacterial invasion of the amniotic cavity and risk of preterm birth is often due to cervicovaginal bacteria such as genital mycoplasmas (Mycoplasma hominis and Ureaplasma urealyticum) and Gardnerella vaginalis. The most studied biomarker associated with preterm birth is interleukin-6 (IL-6), a pleiotropic cytokine that performs different functions based on classical or trans-signaling mechanisms. This study evaluated the changes in IL-6 and IL-6 function associated accessory molecules by human fetal membranes to determine the functional availability of IL-6 assessment in an in vitro model of polybacterial infection. Fetal membranes were treated with LPS or heat-inactivated genital mycoplasmas and G. vaginalis alone or in combination. IL-6 and its soluble receptors (sgp130, sIL-6R) were assessed in conditioned medium by immunoassays and membrane-bound receptors were evaluated in the tissue using immunohistochemistry and RT-PCR. Data from protein and gene expression were evaluated using linear mixed effects models. Data from immunohistochemistry were evaluated using one-way analysis of variance followed by the Tukey test. Genital mycoplasmas alone, or in combination, inhibited IL-6 trans-signaling with increased sgp130 production. G. vaginalis activated the classical IL-6 signaling pathway, as did LPS. Polybacterial treatment resulted in a balanced response with neither pathway being favored. The increase in IL-6 production by fetal membranes in response to infection is likely a non-specific innate response and not an indicator of a functional mediator of any labor-inducing pathways. This suggests that correlating the risk of adverse pregnancy outcomes and designing interventions based on IL-6 levels without considering soluble receptors may be an ineffective strategy.


Assuntos
Infecções Bacterianas/imunologia , Biomarcadores/metabolismo , Membranas Extraembrionárias/metabolismo , Gardnerella vaginalis/fisiologia , Interleucina-6/metabolismo , Mycoplasma/fisiologia , Nascimento Prematuro/imunologia , Receptor gp130 de Citocina/metabolismo , Feminino , Humanos , Imunidade Inata , Gravidez , Resultado da Gravidez , Nascimento Prematuro/microbiologia , Receptores de Interleucina-6/metabolismo , Transdução de Sinais
3.
Parasit Vectors ; 9(1): 642, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27978844

RESUMO

BACKGROUND: In Argentina, only very few reports are available for canine tick-borne diseases where most are related to parasitic diseases. The objective of this survey was to investigate the prevalence of tick-borne pathogens in 70 dogs from Santa Fé and Córdoba, Argentina. METHODS: Microscopic blood smear examination as well as polymerase chain reaction (PCR) amplification using species-specific markers of Anaplasma, Babesia, Bartonella, Borrelia, Ehrlichia, Francisella, Mycoplasma (hemotropic group) and Rickettsia, followed by DNA sequencing were used to establish the prevalence of each infecting pathogen. RESULTS: Blood smear analysis showed 81% (57/70) prevalence of structures morphologically compatible with hemotropic mycoplasmas. No structures resembling either piroplasms or Anaplasma/Ehrlichia were detected. Hemotropic mycoplasma species (Mycoplasma haematoparvum, Mycoplasma haemocanis and Mycoplasma suis) were the most prevalent pathogens detected with an overall prevalence of 77.1%. Anaplasma platys was detected and identified in 11 of the 70 dogs (15.7%), meanwhile two Bartonella spp. (B. clarridgeiae and an uncharacterized Bartonella sp.) and Babesia vogeli were detected at 3 and 7% prevalence, respectively. CONCLUSIONS: The work presented here describes a high molecular prevalence for hemotropic mycoplasma species in each of the five locations selected. Three Mycoplasma spp., including Mycoplasma suis, reported for the first time in dogs have been identified by DNA amplification and sequencing. This study highlights the risk that these bacterial pathogens represent for companion animals and, due to their potential zoonotic nature, also for people.


Assuntos
Doenças do Cão/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Doenças Transmitidas por Carrapatos/veterinária , Animais , Argentina/epidemiologia , Doenças do Cão/epidemiologia , Cães , Feminino , Masculino , Mycoplasma/classificação , Mycoplasma/genética , Mycoplasma/fisiologia , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/microbiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/microbiologia
6.
Vet Microbiol ; 167(3-4): 448-54, 2013 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24176254

RESUMO

Very little is known about the diseases affecting the Darwin's fox (Lycalopex fulvipes), which is considered to be one of the most endangered carnivores worldwide. Blood samples of 30 foxes captured on Chiloé Island (Chile) were tested with a battery of PCR assays targeting the following pathogens: Ehrlichia/Anaplasma sp., Rickettsia sp., Bartonella sp., Coxiella burnetti, Borrelia sp., Mycoplasma sp., Babesia sp., Hepatozoon canis, Hepatozoon felis, Leishmania donovani complex, and Filariae. Analysis of the 16S rRNA gene revealed the presence of Mycoplasma spp. in 17 samples (56.7%, 95% Confidence Intervals= 38.2-73.7). Of these, 15 infections were caused by a Mycoplasma belonging to the M. haemofelis/haemocanis (Mhf/Mhc) group, whereas two were caused by a Mycoplasma showing between 89% and 94% identity with different Candidatus Mycoplasma turicensis from felids and rodents hemoplasmas. The analysis of the sequence of the RNA subunit of the RNase P gene of 10 of the foxes positive for Mhf/Mhc showed that eight were infected with M. haemocanis (Mhc), one with a Mycoplasma showing 94% identity with Mhc, and one by M. haemofelis (Mhf). One of the foxes positive for Mhc was infected with a Ricketssia closely related to R. felis. All foxes were negative for the other studied pathogens. Our results are of interest because of the unexpectedly high prevalence of Mycoplasma spp. detected, the variability of species identified, the presence of a potentially new species of hemoplasma, and the first time a hemoplasma considered to be a feline pathogen (Mhf) has been identified in a canid. Though external symptoms were not observed in any of the infected foxes, further clinical and epidemiological studies are necessary to determine the importance of hemoplasma infection in this unique species.


Assuntos
Espécies em Perigo de Extinção , Raposas/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma/fisiologia , Animais , Chile/epidemiologia , DNA Bacteriano/genética , Feminino , Masculino , Dados de Sequência Molecular , Mycoplasma/classificação , Mycoplasma/genética , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/microbiologia , Reação em Cadeia da Polimerase/veterinária , Prevalência , RNA Ribossômico 16S/genética , Ribonuclease P/genética , Rickettsia/genética , Rickettsia/isolamento & purificação , Infecções por Rickettsia/diagnóstico , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/microbiologia , Infecções por Rickettsia/veterinária , Homologia de Sequência do Ácido Nucleico
7.
Rev Argent Microbiol ; 42(1): 18-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20461288

RESUMO

This study was designed to evaluate the effect of mycoplasma contamination on acid hydrolase activity and the action of the mycoplasma removal agent (MRA), in cultures of human fibroblasts from individuals with lysosomal diseases. For this purpose, we measured the activity of the b-galactosidase, arylsulphatase B (ASB), hexosaminidase A and a-glucosidase enzymes. The activity of the above mentioned enzymes in fibroblasts contaminated by mycoplasma was measured before and after the addition of the MRA. The results were then compared to the enzymatic activity in contamination-free cultures. Only the ASB enzyme showed significant alteration in activity both in the presence of mycoplasma and MRA. The remaining enzymes did not suffer significant interference by the presence of the two agents. Of the four enzymes tested, three did not suffer significant alterations by the presence of the mycoplasma nor from the MRA. However, the activity measured in the ASB enzyme increased significantly in the presence of mycoplasma and MRA and could lead to a doubtful diagnosis. Therefore, we suggest that contamination should be prevented by using aseptic techniques as well as the MRA in those fibroblast cultures that cannot be discarded.


Assuntos
Antibacterianos/farmacologia , Fibroblastos/microbiologia , Hexosaminidase A/análise , Doenças por Armazenamento dos Lisossomos/enzimologia , Mycoplasma/fisiologia , N-Acetilgalactosamina-4-Sulfatase/análise , alfa-Glucosidases/análise , beta-Galactosidase/análise , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/enzimologia , Células Cultivadas/microbiologia , Erros de Diagnóstico/prevenção & controle , Reações Falso-Negativas , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Humanos , Doenças por Armazenamento dos Lisossomos/diagnóstico , Doenças por Armazenamento dos Lisossomos/patologia , Mucopolissacaridose VI/diagnóstico , Mucopolissacaridose VI/enzimologia , Mucopolissacaridose VI/patologia , Quinolonas/farmacologia
8.
Vet Microbiol ; 140(1-2): 167-70, 2010 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-19646827

RESUMO

Two canine haemoplasma species have been recognised to date; Mycoplasma haemocanis (Mhc), which has been associated with anaemia in splenectomised or immunocompromised dogs, and "Candidatus Mycoplasma haematoparvum" (CMhp), recently described in an anaemic splenectomised dog undergoing chemotherapy. The study aim was to develop quantitative real-time PCR assays (qPCRs) incorporating an endogenous internal control to detect Mhc and CMhp and to apply these assays to DNA samples extracted from canine blood collected in Northern Tanzania (n=100) and from dogs presented to a Trinidadian veterinary hospital (n=185). QPCRs specific for Mhc and CMhp were designed using 16S rRNA gene sequence data, and each was duplexed with an assay specific for canine glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The assays detected < or =10 copies of a sequence-specific haemoplasma plasmid per reaction and neither assay showed cross-reactivity with 10(6) copies of the sequence-specific plasmid from the non-target canine haemoplasma species. Nineteen of the 100 Tanzanian samples (19%) were positive for Mhc alone and one (1%) was dually infected. One Trinidadian sample was negative for canine GAPDH DNA and was excluded from the study. Of the 184 remaining Trinidadian samples, nine (4.9%) were positive for Mhc alone, five (2.7%) for CMhp alone, and two (1.1%) dually infected. This is the first report of canine haemoplasma qPCR assays that use an internal control to confirm the presence of amplifiable sample DNA, and their application to prevalence studies. Mhc was the most commonly detected canine haemoplasma species.


Assuntos
Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia , Infecções por Mycoplasma/veterinária , Mycoplasma/fisiologia , Reação em Cadeia da Polimerase/veterinária , Animais , DNA Bacteriano/análise , DNA Bacteriano/sangue , DNA Bacteriano/genética , Doenças do Cão/microbiologia , Cães , Feminino , Masculino , Mycoplasma/genética , Mycoplasma/isolamento & purificação , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/epidemiologia , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade , Tanzânia/epidemiologia , Trinidad e Tobago/epidemiologia
9.
Vet Pathol ; 40(4): 395-404, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12824511

RESUMO

Porcine enzootic pneumonia (PEN), caused by Mycoplasma hyopneumoniae (Mh), has been described in pigs in all geographic areas. The disease is characterized by high morbidity and low mortality rates in intensive swine production systems. A morphologic and immunohistochemical study was done to determine the cellular populations present in lung parenchyma of infected pigs, with special attention to the bronchus-associated lymphoid tissue (BALT). Polyclonal and monoclonal antibodies were used for the detection of antigens of Mh, T lymphocytes (CD3+, CD4+, and CD8+), IgG+ or IgA+ lymphocytes, and cells containing lysozyme, S-100 protein, major histocompatibility complex class II antigen or myeloid-histiocyte antigen. Findings in lung tissues associated with Mh infection were catarrhal bronchointerstitial pneumonia, with infiltration of inflammatory cells in the lamina propria of bronchi and bronchioles and alveolar septa. Hyperplasia of mononuclear cells in the BALT areas was the most significant histologic change. The BALT showed a high morphologic and cellular organization. Macrophages and B lymphocytes were the main cellular components of germinal centers. T lymphocytes were primarily located in perifollicular areas of the BALT, lamina propria and within the airway epithelium, and plasma cells containing IgG or IgA at the periphery of the BALT, in the lamina propria of bronchi and bronchioles, in alveolar septa, and around bronchial submucosal glands. The hyperplastic BALT in PEN cases consisted of macrophages, dendritic cells, T and B lymphocytes, and IgG+ and IgA+ plasma cells. CD4+ cells predominated over CD8+ cells. Local humoral immunity appears to play an important role in the infection.


Assuntos
Brônquios/microbiologia , Brônquios/patologia , Tecido Linfoide/microbiologia , Tecido Linfoide/patologia , Infecções por Mycoplasma/patologia , Infecções por Mycoplasma/veterinária , Mycoplasma/fisiologia , Animais , Brônquios/ultraestrutura , Imuno-Histoquímica , Tecido Linfoide/ultraestrutura , Infecções por Mycoplasma/microbiologia , Suínos , Doenças dos Suínos/microbiologia , Doenças dos Suínos/patologia
10.
J Leukoc Biol ; 65(6): 808-14, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10380903

RESUMO

Bacterial products stimulate macrophage tumoricidal activity through release of tumor necrosis factor (TNF) and nitric oxide (NO). We show here that thioglycollate-elicited macrophages acquire cytotoxic activity when cocultured with Mycoplasma arginini-infected YAC-1 tumor cells and release TNF and NO. Fixed mycoplasma-infected cells, supernatants from infected-cell cultures, or purified heat-killed mycoplasma obtained from cell-free cultures were all able to induce TNF and NO production. Thus, the mycoplasma per se and not a product of infected cells induce the release of these molecules. Addition of prostaglandin E2 (PGE2) to the cocultures, which reduced TNF release, or antibodies to TNF, did not affect macrophage cytotoxicity nor NO release. Inhibition of NO production by L-NAME or aminoguanidine reduced the cytotoxicity, and treatment with a NO donor was toxic to YAC-1 cells. These results indicate that M. arginini activates thioglycollate-elicited murine macrophages for NO and TNF release increasing their cytotoxic activity toward YAC-1 cells and that this activity is dependent on NO but not TNF release.


Assuntos
Cromossomos Artificiais de Levedura/microbiologia , Macrófagos/citologia , Mycoplasma/fisiologia , Óxido Nítrico/biossíntese , Tioglicolatos/farmacologia , Animais , Cromossomos Artificiais de Levedura/imunologia , Citotoxicidade Imunológica , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Mycoplasma/fisiopatologia , Fator de Necrose Tumoral alfa/metabolismo
11.
FEMS Immunol Med Microbiol ; 15(2-3): 123-8, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8880137

RESUMO

The mycoplasmas comprise a discrete group of microorganisms that are known to exert a range of effects upon cells derived from the immune system. Some of these interactions turn out to be immunomodulatory, such as polyclonal stimulation of T and B cells or enhancement of the cytolytic potential of macrophages, NK cells and T lymphocytes. Immunologically committed cells, when infected with mycoplasmas, can also increase the production of cytokines (IL-1, IL-2, IL-4 and IL-6), interferon (IFN) gamma, tumor necrosis factor-alpha (TNF-alpha) and colony-stimulating factors (particularly GM-CSF). Moreover, mycoplasmas are potent inductors of cytokine secretion by fibroblasts in culture. Since growth factors are determinants for the activation and proliferation of immunocompetent cells in vitro, we decided to investigate if these effects are concordant with the finding of mycoplasma contamination. In order to address this question, we compared the pattern of lymphokine secretion by normal-derived human fibroblasts in culture with and without Mycoplasma spp. contamination. We found those human fibroblasts that have been contaminated with mycoplasma show production of IL-13 at the transcriptional level. This effect coincides with discrete morphological changes as compared to uncontaminated human fibroblasts. This is the first report to acknowledge that mycoplasma contamination can induce mRNA expression for IL-13 in cultured human fibroblasts.


Assuntos
Fibroblastos/imunologia , Fibroblastos/microbiologia , Interleucina-13/biossíntese , Mycoplasma/fisiologia , Linhagem Celular , Células Cultivadas , Fibroblastos/citologia , Humanos , Interleucina-13/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Pele
12.
J Appl Bacteriol ; 72(1): 51-6, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1541600

RESUMO

Fluidity and composition of cell membranes during progression of Mycoplasma canadense cultures grown in a serum-free medium was assessed. The fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene at 25 degrees C of intact cells and liposomes in the exponential and stationary phases of growth was compared. A decrease in fluidity and an increase in the ratio of saturated to unsaturated fatty acids was detected in cell membranes on aging. Nevertheless, membrane density remained unaltered although the molar ratio of cholesterol to phospholipids decreased. It is proposed that the increase in lipid order is primarily due to the increase in the ratio of saturated to unsaturated membrane fatty acids, being the diminished molar ratio of cholesterol to phospholipids involved in the reduced unsaturated fatty acid uptake.


Assuntos
Mycoplasma/crescimento & desenvolvimento , Proteínas da Membrana Bacteriana Externa/análise , Membrana Celular/química , Membrana Celular/fisiologia , Centrifugação Isopícnica , Meios de Cultura , Difenilexatrieno/metabolismo , Eletroforese em Gel de Poliacrilamida , Ácidos Graxos/análise , Polarização de Fluorescência , Soluções Hipotônicas , Fluidez de Membrana , Mycoplasma/química , Mycoplasma/fisiologia , Fragilidade Osmótica , Fatores de Tempo
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