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1.
Front Endocrinol (Lausanne) ; 14: 1208182, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492199

RESUMO

Thyroid hormones (THs) regulate tissue remodeling processes during early- and post-embryonic stages in vertebrates. The Mexican axolotl (Ambystoma mexicanum) is a neotenic species that has lost the ability to undergo metamorphosis; however, it can be artificially induced by exogenous administration of thyroxine (T4) and 3,3',5-triiodo-L-thyronine (T3). Another TH derivative with demonstrative biological effects in fish and mammals is 3,5-diiodo-L-thyronine (3,5-T2). Because the effects of this bioactive TH remains unexplored in other vertebrates, we hypothesized that it could be biologically active in amphibians and, therefore, could induce metamorphosis in axolotl. We performed a 3,5-T2 treatment by immersion and observed that the secondary gills were retracted, similar to the onset stage phenotype; however, tissue regeneration was observed after treatment withdrawal. In contrast, T4 and T3 immersion equimolar treatments as well as a four-fold increase in 3,5-T2 concentration triggered complete metamorphosis. To identify the possible molecular mechanisms that could explain the contrasting reversible or irreversible effects of 3,5-T2 and T3 upon gill retraction, we performed a transcriptomic analysis of differential expression genes in the gills of control, 3,5-T2-treated, and T3-treated axolotls. We found that both THs modify gene expression patterns. T3 regulates 10 times more genes than 3,5-T2, suggesting that the latter has a lower affinity for TH receptors (TRs) or that these hormones could act through different TR isoforms. However, both TH treatments regulated different gene sets known to participate in tissue development and cell cycle processes. In conclusion, 3,5-T2 is a bioactive iodothyronine that promoted partial gill retraction but induced full metamorphosis in higher concentrations. Differential effects on gill retraction after 3,5,-T2 or T3 treatment could be explained by the activation of different clusters of genes related with apoptosis, regeneration, and proliferation; in addition, these effects could be initially mediated by TRs that are expressed in gills. This study showed, for the first time, the 3,5,-T2 bioactivity in a neotenic amphibian.


Assuntos
Ambystoma mexicanum , Brânquias , Animais , Ambystoma mexicanum/metabolismo , Brânquias/metabolismo , Tiroxina/farmacologia , Hormônios Tireóideos/metabolismo , Mamíferos/metabolismo
2.
Gen Comp Endocrinol ; 334: 114225, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36709002

RESUMO

The zebrafish is an optimal experimental model to study thyroid hormone (TH) involvement in vertebrate development. The use of state-of-the-art zebrafish genetic tools available for the study of the effect of gene silencing, cell fate decisions and cell lineage differentiation have contributed to a more insightful comprehension of molecular, cellular, and tissue-specific TH actions. In contrast to intrauterine development, extrauterine embryogenesis observed in zebrafish has facilitated a more detailed study of the development of the hypothalamic-pituitary-thyroid axis. This model has also enabled a more insightful analysis of TH molecular actions upon the organization and function of the brain, the retina, the heart, and the immune system. Consequently, zebrafish has become a trendy model to address paradigms of TH-related functional and biomedical importance. We here compilate the available knowledge regarding zebrafish developmental events for which specific components of TH signaling are essential.


Assuntos
Hormônios Tireóideos , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Encéfalo/metabolismo , Transdução de Sinais
3.
Sci Rep ; 9(1): 7359, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089165

RESUMO

In contrast to mammalian adults, myelination in teleosts occurs throughout their lifespan and most of the progenitor cells are originated in the cerebellum. To understand the role that thyroid hormones (THs) play in juvenile cerebellar myelination in teleosts, we identified and localised the expression of genes involved in TH signalling (mct8, oatp1c1, dio2, dio3, thraa and l-thrb1) and analysed the effects of the two bioactive THs, T2 and T3, upon their regulation, as well as upon some structural components of the myelination process. Ex vivo approaches using organotypic cerebellar cultures followed by FISH and qPCR showed gene-specific localisation and regulation of TH signalling genes in the cerebellar nuclei. In vivo approaches using methimazole (MMI)-treated juvenile tilapias replaced with low doses of T3 and T2 showed by immunofluorescence that myelin fibres in the cerebellum are more abundant in the granular layer and that their visible size is reduced after MMI treatment but partially restored with TH replacement, suggesting that low doses of TH promote the re-myelination process in an altered condition. Together, our data support the idea that T2 and T3 promote myelination via different pathways and prompt T2 as a target for further analysis as a promising therapy for hypomyelination.


Assuntos
Cerebelo/crescimento & desenvolvimento , Ciclídeos/crescimento & desenvolvimento , Di-Iodotironinas/metabolismo , Bainha de Mielina/metabolismo , Tri-Iodotironina/metabolismo , Animais , Técnicas de Cultura de Células/métodos , Cerebelo/metabolismo , Ciclídeos/metabolismo , Regulação da Expressão Gênica/fisiologia , Masculino , Modelos Animais , Transdução de Sinais/fisiologia , Glândula Tireoide/metabolismo
4.
Sci Rep ; 7(1): 15043, 2017 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-29118400

RESUMO

Although 3,5,3'-triiodothyronine (T3) is considered to be the primary bioactive thyroid hormone (TH) due to its high affinity for TH nuclear receptors (TRs), new data suggest that 3,5-diiodothyronine (T2) can also regulate transcriptional networks. To determine the functional relevance of these bioactive THs, RNA-seq analysis was conducted in the cerebellum, thalamus-pituitary and liver of tilapia treated with equimolar doses of T2 or T3. We identified a total of 169, 154 and 2863 genes that were TH-responsive (FDR < 0.05) in the tilapia cerebellum, thalamus-pituitary and liver, respectively. Among these, 130, 96 and 349 genes were uniquely regulated by T3, whereas 22, 40 and 929 were exclusively regulated by T2 under our experimental paradigm. The expression profiles in response to TH treatment were tissue-specific, and the diversity of regulated genes also resulted in a variety of different pathways being affected by T2 and T3. T2 regulated gene networks associated with cell signalling and transcriptional pathways, while T3 regulated pathways related to cell signalling, the immune system, and lipid metabolism. Overall, the present work highlights the relevance of T2 as a key bioactive hormone, and reveals some of the different functional strategies that underpin TH pleiotropy.


Assuntos
Encéfalo/metabolismo , Di-Iodotironinas/farmacologia , Fígado/metabolismo , Tilápia/genética , Transcriptoma/efeitos dos fármacos , Tri-Iodotironina/farmacologia , Animais , Análise por Conglomerados , Proteínas de Peixes/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Especificidade de Órgãos/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
5.
HLA ; 90(4): 234-237, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28677168

RESUMO

Associations between HLA class II polymorphisms and HIV control were assessed in a Peruvian MSM cohort. Among 233 treatment naïve HIV+ individuals, DRB1*13:02 was linked to elevated viral loads (P = .044) while DRB1*12:01 showed significantly lower viral set points (P = .015) and restricted a dominant T cell response to HIV Gag p24 (P = .038). The present work contributes to a better knowledge of the Peruvian immunogenetics and supports the important role of HLA class II restricted T cells in HIV control.


Assuntos
Alelos , Infecções por HIV/genética , Cadeias HLA-DRB1/genética , Homossexualidade Masculina , Polimorfismo Genético , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Estudos de Coortes , Feminino , Expressão Gênica , Frequência do Gene , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Cadeias HLA-DRB1/imunologia , Humanos , Masculino , Peru , Carga Viral
6.
J Virol ; 91(16)2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28592538

RESUMO

Intact and broad immune cell effector functions and specific individual cytokines have been linked to HIV disease outcome, but their relative contribution to HIV control remains unclear. We asked whether the proteome of secreted cytokines and signaling factors in peripheral blood can be used to discover specific pathways critical for host viral control. A custom glass-based microarray, able to measure >600 plasma proteins involved in cell-to-cell communication, was used to measure plasma protein profiles in 96 HIV-infected, treatment-naive individuals with high (>50,000) or low (<10,000 HIV RNA copies/ml) viral loads. Univariate and regression model analysis demonstrate that plasma levels of soluble interleukin-27 (IL-27) are significantly elevated in individuals with high plasma viremia (P < 0.0001) and are positively correlated with proviral HIV-DNA copy numbers in peripheral blood mononuclear cells (PBMC) (Rho = 0.4011; P = 0.0027). Moreover, soluble IL-27 plasma levels are negatively associated with the breadth and magnitude of the total virus-specific T-cell responses and directly with plasma levels of molecules involved in Wnt/ß-catenin signaling. In addition to IL-27, gene expression levels of the specific IL-27 receptor (IL27RA) in PBMC correlated directly with both plasma viral load (Rho = 0.3531; P = 0.0218) and the proviral copy number in the peripheral blood as an indirect measure of partial viral reservoir (Rho = 0.4580; P = 0.0030). These results were validated in unrelated cohorts of early infected subjects as well as subjects before and after initiation of antiretroviral treatment, and they identify IL-27 and its specific receptor as a critical immune axis for the antiviral immune response and as robust correlates of viral load and proviral reservoir size in PBMC.IMPORTANCE The detailed knowledge of immune mechanisms that contribute to HIV control is a prerequisite for the design of effective treatment strategies to achieve HIV cure. Cells communicate with each other by secreting signaling proteins, and the blood is a key conduit for transporting such factors. Investigating the communication factors promoting effective immune responses and having potentially antiviral functions against HIV using a novel focused omics approach ("communicome") has the potential to significantly improve our knowledge of effective host immunity and accelerate the HIV cure agenda. Including 140 subjects with variable viral loads and measuring the plasma levels of >600 soluble proteins, our data highlight the importance of Th17 cells and Wnt/ß-catenin signaling in HIV control and especially identify the IL-27/IL-27 receptor subunit alpha (IL-27RA) axis as a predictor of plasma viral load and proviral copy number in the peripheral blood. These data may provide important guidance to therapeutic approaches in the HIV cure agenda.


Assuntos
Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV/imunologia , Interleucinas/metabolismo , Receptores de Interleucina/metabolismo , Carga Viral , Proteínas Sanguíneas/análise , Perfilação da Expressão Gênica , Humanos , Leucócitos Mononucleares/imunologia , Análise Serial de Proteínas
7.
J Cell Biochem ; 118(12): 4468-4478, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28464260

RESUMO

Extracellular nucleotides and nucleosides have emerged as important elements regulating tissue homeostasis. Acting through specific receptors, have the ability to control gene expression patterns to direct cellular fate. We observed that SKOV-3 cells express the ectonucleotidases: ectonucleotide pyrophosphatase 1 (ENPP1), ecto-5'-nucleotidase (NT5E), and liver alkaline phosphatase (ALPL). Strikingly, in pulse and chase experiments supplemented with ATP, SKOV-3 cells exhibited low catabolic efficiency in the conversion of ADP into AMP, but they were efficient in converting AMP into adenosine. Since these cells release ATP, we proposed that the conversion of ADP into AMP is a regulatory node associated with the migratory ability and the mesenchymal characteristics shown by SKOV-3 cells under basal conditions. The landscape of gene expression profiles of SKOV-3 cell cultures treated with apyrase or adenosine demonstrated similarities (e.g., decrease FGF16 transcript) and differences (e.g., the negative regulation of Wnt 2, and 10B by adenosine). Thus, in SKOV-3 we analyzed the migratory ability and the expression of epithelium to mesenchymal transition (EMT) markers in response to apyrase. Apyrase-treatment favored the epithelial-like phenotype, as revealed by the re-location of E-cadherin to the cell to cell junctions. Pharmacological approaches strongly suggested that the effect of Apyrase involved the accumulation of extracellular adenosine; this notion was strengthened when the incubation of the SKOV-3 cell with α,ß-methylene ADP (CD73 inhibitor) or adenosine deaminase was sufficient to abolish the effect of apyrase on cell migration. Overall, adenosine signaling is a fine tune mechanism in the control of cell phenotype in cancer. J. Cell. Biochem. 118: 4468-4478, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Movimento Celular/efeitos dos fármacos , Neoplasias Ovarianas/metabolismo , Purinas/farmacologia , Apirase/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Proteínas de Neoplasias/metabolismo , Purinas/metabolismo
8.
Nanoscale ; 7(21): 9452-6, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-25965176

RESUMO

The use of template nanostructures for the creation of photovoltaic and thermoelectric semiconductors is becoming a quickly expanding synthesis strategy. In this work we report a simple two-step process enabling the formation of ternary CuAgSe nanoplatelets with a great degree of control over the composition and shape. Starting with hexagonal nanoplatelets of cubic Cu2-xSe, ternary CuAgSe nanoplatelets were generated through a rapid ion exchange reaction at 300 K using AgNO3 solution. The Cu2-xSe nanoplatelet template and the final CuAgSe nanoplatelets were analyzed by electron microscopy and X-ray diffraction (XRD). It was found that both the low temperature pseudotetragonal and the high temperature cubic forms of CuAgSe phase were created while maintaining the morphology of the Cu2-xSe nanoplatelet template. Thermal and electronic transport measurements of hot-pressed pellets of the synthesized CuAgSe nanoplatelets showed a drastic reduction in the thermal conductivity and a sharp transition from n-type (S = -45 µV K(-1)) to p-type (S = +200 µV K(-1)) semiconducting behavior upon heating above the structural transition from the low temperature orthorhombic to the high temperature super-ionic cubic phase. This simple reaction process utilizing a template nanostructure matrix represents an energy efficient, cost-efficient, and versatile strategy to create interesting materials with lower defect density and superior thermoelectric performance.

9.
J Comp Pathol ; 146(1): 4-10, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21601873

RESUMO

Between 2008 and 2009, three pet ferrets from different sources presented with acute episode of dyspnoea. Cytological examination of pleural exudates revealed severe purulent inflammation with abundant clusters of rod-shaped microorganisms with a clear surrounding halo. Treatment was ineffective and the ferrets died 2-5 days later. Two ferrets were subjected to necropsy examination, which revealed pyothorax, mediastinal lymphadenopathy and multiple white nodules (1-2mm) in the lungs. Microscopical examination showed multifocal necrotizing-pyogranulomatous pleuropneumonia and lymphadenitis with aggregates of encapsulated microorganisms, some of which were positively stained by periodic acid-Schiff and alcian blue. In-situ hybridization for Pneumocystis spp., Ziehl-Neelsen staining and immunohistochemistry for distemper, coronavirus and influenza antigen were negative in all cases. Electron microscopically, the bacteria were 2-3 µm long with a thick electron-lucent capsule. Microbiology from one ferret yielded a pure culture of gram-negative bacteria identified phenotypically as Pseudomonas luteola. This speciation was later confirmed by 16S RNA gene amplification.


Assuntos
Furões/microbiologia , Mediastinite/veterinária , Pleuropneumonia/veterinária , Infecções por Pseudomonas/veterinária , Animais , Mediastinite/microbiologia , Pleuropneumonia/microbiologia , Pseudomonas , Infecções por Pseudomonas/microbiologia
10.
J Comp Pathol ; 146(2-3): 269-73, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21601871

RESUMO

During 2007 a dolphin morbillivirus epizootic affected the western Mediterranean and several striped dolphins (Stenella coeruleoalba) stranded on the Catalonian coasts. One of those animals had severe lymphoid depletion, necrosis and syncytial formation in lymph nodes and spleen, with large basophilic nuclear inclusions compatible with herpesvirus detected by immunohistochemical and ultrastructural examination. Non-suppurative encephalitis with associated morbillivirus antigen and morbillivirus antigen within alveolar macrophages were also observed. A pan-herpesvirus nested polymerase chain reaction amplified a sequence virtually identical to two cetacean herpesvirus sequences previously identified in systemic infections in an Atlantic Cuvier's beaked whale (Ziphius cavirostris) and in a Mediterranean striped dolphin. The herpesviral infection was probably secondary to the immunosuppression caused by the morbillivirus. To our knowledge, this is the first report of a cetacean co-infected by dolphin morbillivirus and herpesvirus with evidence of lesions attributable to both viruses.


Assuntos
Coinfecção/veterinária , Infecções por Herpesviridae/veterinária , Herpesviridae , Infecções por Morbillivirus/veterinária , Morbillivirus , Stenella/virologia , Animais , Coinfecção/diagnóstico , Infecções por Herpesviridae/complicações , Infecções por Herpesviridae/diagnóstico , Infecções por Morbillivirus/complicações , Infecções por Morbillivirus/diagnóstico
11.
Neuroscience ; 171(4): 1091-101, 2010 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-20875843

RESUMO

Alzheimer's disease (AD) is characterized by neuronal loss and the presence of both neurofibrillary tangles and senile plaques in the brain. These plaques arise from the deposition of beta-amyloid (Aß) peptides (38-43 amino acids), which are generated from enzymatic cleavage of the amyloid precursor protein (APP) by ß- and γ-secretases. In the present work, we cloned the principal APP isoforms as well as some enzymes that have been implicated in their amyloidogenic and non-amyloidogenic processing in dogs. Additionally, the main proteases implicated in the degradation of Aß were also studied. We also investigated the level of expression of these APP isoforms and enzymes in different brain regions and in peripheral tissues. Our data demonstrate that these canine proteins are highly homologous to their human counterparts. In addition, the expression pattern of these proteins in dogs is consistent with previous data reported in human beings. Thus, dogs may be a natural model to study the biology of AD and could also serve as an animal model for Aß-targeted drugs against this devastating disease.


Assuntos
Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Clonagem Molecular/métodos , Presenilinas/genética , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Cães , Feminino , Expressão Gênica/genética , Humanos , Masculino , Dados de Sequência Molecular , Presenilinas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA/métodos
12.
Vet Microbiol ; 145(3-4): 315-20, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-20447775

RESUMO

Haemophilus parasuis is the etiologic agent of Glässer's disease in pigs and a colonizer of the upper respiratory tract of healthy pigs. A good balance between colonization and immunity is important to avoid a disease outbreak. This work studied the colonization of H. parasuis in healthy piglets coming from vaccinated and non-vaccinated sows. Piglets from vaccinated sows had higher IgG levels at early time points and subsequently were colonized later and to a lower degree than piglets from non-vaccinated ones. The variability of H. parasuis isolates was investigated by 2 genotyping methods: enterobacterial repetitive intergenic consensus (ERIC)-PCR and multilocus sequence typing (MLST). A high turnover of strains was found in both groups of piglets, with few strains found on more than one sampling occasion. We found a higher number of H. parasuis strains (16 strains) within a given farm than previously thought. Overall, more H. parasuis diversity was found in piglets from non-vaccinated sows than in those from vaccinated sows. These results indicate that vaccination of sows in a farm delays the colonization of piglets and reduces the carriage and heterogeneity of H. parasuis strains.


Assuntos
Vacinas Bacterianas/imunologia , Infecções por Haemophilus/veterinária , Haemophilus parasuis/imunologia , Doenças Respiratórias/veterinária , Doenças dos Suínos/microbiologia , Animais , Animais Recém-Nascidos , Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/farmacologia , Análise por Conglomerados , Impressões Digitais de DNA/métodos , Impressões Digitais de DNA/veterinária , Feminino , Variação Genética , Genótipo , Infecções por Haemophilus/imunologia , Infecções por Haemophilus/microbiologia , Infecções por Haemophilus/prevenção & controle , Haemophilus parasuis/genética , Imunidade Materno-Adquirida/imunologia , Reação em Cadeia da Polimerase/veterinária , Doenças Respiratórias/imunologia , Doenças Respiratórias/microbiologia , Doenças Respiratórias/prevenção & controle , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/prevenção & controle , Vacinação/métodos , Vacinação/veterinária
13.
Int J Syst Evol Microbiol ; 60(Pt 10): 2446-2450, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19946050

RESUMO

Nine Gram-negative, catalase- and oxidase-positive, coccus-shaped bacteria were isolated from pigs affected by different pathological processes. Phenotypic and genotypic methods were adopted to determine the relationships of these new isolates to recognized species of the genus Moraxella. Analysis of the 16S rRNA gene sequences demonstrated that the clinical isolates represented a new lineage within the genus Moraxella. The isolates were closely related to Moraxella cuniculi and Moraxella pluranimalium with 16S rRNA gene sequence similarities of 98.1 % and 99.1 %, respectively. The isolates displayed DNA-DNA relative binding ratios of 74 % to each other, but distinctly lower levels of DNA-DNA hybridization were observed with phylogenetically closely related moraxellae (<32 %). The new isolates could be distinguished from all other recognized species of the genus Moraxella by physiological and biochemical tests. On the basis of the phenotypic and molecular data, the nine new isolates from pigs represent a novel species within the genus Moraxella, for which the name Moraxella porci sp. nov. is proposed. The type strain is SN9-4M(T) (=CECT 7294(T)=CCUG 54912(T)).


Assuntos
Moraxella/classificação , Moraxella/isolamento & purificação , Suínos/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Catalase/metabolismo , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Dados de Sequência Molecular , Moraxella/genética , Moraxella/fisiologia , Hibridização de Ácido Nucleico , Oxirredutases/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
Vet Microbiol ; 128(1-2): 23-35, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-17976930

RESUMO

Porcine circovirus type 2 (PCV2) is the essential infectious agent of postweaning multisystemic wasting syndrome (PMWS). Despite first sequencing studies did not find any association between PCV2 sequences and PMWS occurrence, recent works have suggested the opposite. In the present study, 87 open reading frame 2 (ORF2) sequences obtained from pigs with different clinical conditions and coming from farms with different PMWS status were analyzed. Results further confirmed the existence of two genogroups and the definition of two PCV2 genotypes (1 and 2) is proposed. All sequences included in genotype 1 came from pigs from PMWS affected farms, while all sequences obtained from non-PMWS affected farms corresponded to genotype 2. Moreover, infection of single pigs from PMWS affected farms harbouring both genotypes is described. Present results suggest that PCV2 genotype 1 may potentially be more pathogenic than PCV2 genotype 2.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus/genética , Circovirus/patogenicidade , Síndrome Definhante Multissistêmico de Suínos Desmamados/virologia , Sequência de Aminoácidos , Criação de Animais Domésticos , Animais , Sequência de Bases , Infecções por Circoviridae/virologia , Circovirus/classificação , DNA Viral/genética , Genótipo , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Suínos
16.
Acta Vet Hung ; 55(3): 389-404, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17867466

RESUMO

This report describes the first case of postweaning multisystemic wasting syndrome (PMWS) in wild boar in Croatia. During the winter season of 2004, eight wild young piglets (of approximately 2 to 5 months of age) were found dead in a fenced hunting area. Polymerase chain reaction (PCR) was carried out on mesenteric lymph nodes and all animals yielded positive results. In one of these animals diagnosis of PMWS was established based on the three key diagnostic criteria including the clinical manifestation, moderate lymphoid lesions consisting of lymphocyte depletion and granulomatous inflammation, and detection of the presence of PCV2 genome within the lymphoid lesions by in situ hybridisation (ISH). Three additional wild piglets had also mild PMWS-like lesions and a low amount of PCV2 was also found. No PMWS-like lesions or PCV2 genome were detected in the rest of the wild piglets studied. Three PCR-positive isolates were partially sequenced, which confirmed the diagnosis of PCV2 and demonstrated that the three sequences were genetically identical. The phylogenetic analysis of a representative PCV2 isolate indicated that its sequence (DQ875444) is grouped in a separate branch with Hungarian isolate (AY256460) and differs from any of the annotated sequences.


Assuntos
Circovirus/classificação , Filogenia , Síndrome Definhante Multissistêmico de Suínos Desmamados/epidemiologia , Sus scrofa , Animais , Animais Recém-Nascidos , Sequência de Bases , Croácia/epidemiologia , Hibridização In Situ/veterinária , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/veterinária , Síndrome Definhante Multissistêmico de Suínos Desmamados/patologia , Síndrome Definhante Multissistêmico de Suínos Desmamados/virologia , Suínos
17.
Vet Microbiol ; 125(1-2): 182-6, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17574352

RESUMO

Haemophilus parasuis is a colonizer of the upper respiratory tract of pigs and the etiological agent of Glässer's disease, which is characterized by a fibrinous polyserositis, meningitis and arthritis. Glässer's disease has never been reported in wild boar (Sus scrofa), although antibodies against H. parasuis have been detected. The goal of this study was to confirm the presence of this bacterium in wild boar by bacterial isolation and to compare the strains to H. parasuis from domesticated pigs. Therefore, nasal swabs from 42 hunted wild boars were processed for bacterial isolation and subsequent H. parasuis identification by specific PCR, biochemical tests and 16S rRNA gene sequencing. Two different strains of H. parasuis from two wild boars were isolated. These strains belonged to serotype 2 and were included by 16S rRNA gene sequencing and MLST analysis in a cluster with other H. parasuis strains of nasal origin from domestic pigs. During this study, Actinobacillus minor and Actinobacillus indolicus, which are NAD-dependent Pasteurellaceae closely related to H. parasuis, were also isolated. Our results indicate similarities in the respiratory microbiota of wild boars and domestic pigs, and although H. parasuis was isolated from wild boars, more studies are needed to determine if this could be a source of H. parasuis infection for domestic pigs.


Assuntos
Infecções por Haemophilus/veterinária , Haemophilus parasuis/isolamento & purificação , NAD/metabolismo , Doenças Respiratórias/veterinária , Doenças dos Suínos/microbiologia , Animais , Anticorpos Antibacterianos/sangue , Sequência de Bases , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Infecções por Haemophilus/microbiologia , Haemophilus parasuis/genética , Haemophilus parasuis/metabolismo , Testes de Hemaglutinação/veterinária , Masculino , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , Doenças Respiratórias/microbiologia , Espanha , Sus scrofa
18.
Vet Microbiol ; 123(1-3): 230-7, 2007 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-17418506

RESUMO

Haemophilus parasuis is a colonizer of the upper respiratory tract of pigs, although it is better known as the etiological agent of Glässer's disease. Interestingly, several strains can be isolated from a single farm, as determined by both genotyping and serotyping. However, it is not known how an outbreak and the subsequent treatment affect the population of H. parasuis strains. In this study, a farm was studied during an outbreak of Glässer's disease and 1 year after antimicrobial treatment and elimination of clinical signs. Bacterial isolation was attempted from nasal swabs and lesions. After isolation, antimicrobial susceptibility, serotype and genotype were determined. Two different genotyping techniques, enterobacterial repetitive intergenic consensus (ERIC)-PCR and multilocus sequence typing (MLST) were used. The H. parasuis strain that was isolated from lesions during the disease outbreak clustered with other virulent strains by both MLST and serotyping analysis. Nasal isolates were included in the corresponding nasal cluster by MLST, but they presented high variability by serotyping. These nasal isolates included serotypes previously classified as virulent and non-virulent. Finally, we found that during the antimicrobial treatment the diversity of strains isolated in the farm was affected and just one strain, which was resistant to the treatment, was detected. One year after the treatment strain diversity was back to normal (three strains).


Assuntos
Surtos de Doenças/veterinária , Infecções por Haemophilus/veterinária , Haemophilus parasuis/genética , Doenças dos Suínos/microbiologia , Animais , Feminino , Genótipo , Infecções por Haemophilus/epidemiologia , Infecções por Haemophilus/microbiologia , Masculino , Filogenia , Suínos , Doenças dos Suínos/epidemiologia
19.
Virology ; 357(2): 175-85, 2007 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-16963096

RESUMO

Porcine circoviruses (PCVs) type 1 (PCV1) and type 2 (PCV2) show high levels of nucleotide similarity, but PCV1 is considered non-pathogenic and PCV2 has been associated with several disease outcomes in pigs, mainly postweaning multisystemic wasting syndrome (PMWS). After exploring different topologies of the origin of PCVs, it was concluded that PCV1 and PCV2 seem to have a common origin. On the other hand, PCV2 could be divided into two groups (1 and 2) and eight clusters (1A to 1C and 2A to 2E), but none of those was apparently associated with disease status or geographic area. When phylogenetic trees constructed with the whole PCV2 genome, the cap or the rep genes were compared, some incongruence was identified. The possible existence of recombination was evaluated and cluster 1B was found to have a possible recombinant origin. Selective pressure was detected in all parts of the PCV2 genome, especially in the rep gene. Finally, the cap gene was the more suitable phylogenetic and epidemiological marker for PCV2, despite the fact that the virus can undergo recombination mainly within the first part of the rep region.


Assuntos
Circovirus/classificação , Circovirus/genética , Evolução Molecular , Genoma Viral , Doenças dos Suínos/virologia , Animais , DNA Viral/genética , Genes Virais , Filogenia , Suínos , Doenças dos Suínos/fisiopatologia
20.
Appl Environ Microbiol ; 72(6): 3984-92, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16751506

RESUMO

Haemophilus parasuis is the cause of Glässer's disease and other clinical disorders in pigs. It can also be isolated from the upper respiratory tracts of healthy pigs, and isolates can have significant differences in virulence. In this work, a partial sequence from the 60-kDa heat shock protein (Hsp60) gene was assessed as an epidemiological marker. We analyzed partial sequences of hsp60 and 16S rRNA genes from 103 strains of H. parasuis and other related species to obtain a better classification of the strains and examine the correlation with virulence. The results were compared with those obtained by enterobacterial repetitive intergenic consensus PCR. Our results showed that hsp60 is a reliable marker for epidemiological studies of H. parasuis and that the analysis of its sequence is a better approach than fingerprinting methods. Furthermore, the analysis of the hsp60 and 16S rRNA gene sequences revealed the presence of a separate lineage of virulent strains and indicated the occurrence of lateral gene transfer among H. parasuis and Actinobacillus strains.


Assuntos
Variação Genética , Haemophilus parasuis/genética , Suínos/microbiologia , Animais , Chaperonina 60/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Haemophilus parasuis/isolamento & purificação , Filogenia , RNA Bacteriano/genética , RNA Bacteriano/isolamento & purificação , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação
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