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1.
Parasitology ; 148(7): 779-786, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33843504

RESUMO

Metchnikovellids are a deep-branching group of microsporidia, parasites of gregarines inhabiting the alimentary tract of polychaetes and some other invertebrates. The diversity and phylogeny of these hyperparasites remain poorly studied. Modern descriptions and molecular data are still lacking for many species. The results of a light microscopy study and molecular data for Metchnikovella spiralis Sokolova et al., 2014, a hyperparasite of the eugregarine Polyrhabdina sp., isolated from the polychaete Pygospio elegans, were obtained. The original description of M. spiralis was based primarily on the analysis of stained preparations and transmission electron microscopy images. Here, the species description was complemented with the results of in vivo observations and phylogenetic analysis based on the SSU rRNA gene. It was shown that in this species, free sporogony precedes sac-bound sporogony, as it occurs in the life cycle of most other metchnikovellids. Spore sacs are entwined with spirally wound cords, and possess only one polar plug. Phylogenetic analyses did not group M. spiralis with M. incurvata, another metchnikovellid from the same gregarine species, but placed it as a sister branch to Amphiacantha. The paraphyletic nature of the genus Metchnikovella was discussed. The taxonomic summary for M. spiralis was emended.


Assuntos
Apicomplexa/parasitologia , Interações Hospedeiro-Parasita , Microsporídios/classificação , Microsporídios/citologia , Poliquetos/parasitologia , Animais , Microsporídios/genética , Microsporídios/fisiologia , Filogenia , RNA de Protozoário/análise , RNA Ribossômico/análise
2.
Parasitol Res ; 120(2): 525-534, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33415389

RESUMO

The species Metchnikovella dogieli (Paskerova et al. Protistology 10:148-157, 2016) belongs to one of the early diverging microsporidian groups, the metchnikovellids (Microsporidia: Metchnikovellidae). In relation to typical ('core') microsporidia, this group is considered primitive. The spores of metchnikovellids have no classical polar sac-anchoring disk complex, no coiled polar tube, no posterior vacuole, and no polaroplast. Instead, they possess a short thick manubrium that expands into a manubrial cistern. These organisms are hyperparasites; they infect gregarines that parasitise marine invertebrates. M. dogieli is a parasite of the archigregarine Selenidium pygospionis (Paskerova et al. Protist 169:826-852, 2018), which parasitises the polychaete Pygospio elegans. This species was discovered in samples collected in the silt littoral zone at the coast of the White Sea, North-West Russia, and was described based on light microscopy. No molecular data are available for this species, and the publicly accessible genomic data for metchnikovellids are limited to two species: M. incurvata Caullery & Mesnil, 1914 and Amphiamblys sp. WSBS2006. In the present study, we applied single-cell genomics methods with whole-genome amplification to perform next-generation sequencing of M. dogieli genomic DNA. We performed a phylogenetic analysis based on the SSU rRNA gene and reconstructed a multigene phylogeny using a concatenated alignment that included 46 conserved single-copy protein domains. The analyses recovered a fully supported clade of metchnikovellids as a basal group to the core microsporidia. Two members of the genus Metchnikovella did not form a clade in our tree. This may indicate that this genus is paraphyletic and requires revision.


Assuntos
Apicomplexa/microbiologia , Microsporídios/genética , Poliquetos/parasitologia , Animais , Evolução Molecular , Genômica , Microsporídios/classificação , Microsporídios/ultraestrutura , Filogenia , Federação Russa , Esporos Fúngicos/ultraestrutura
3.
Mycoses ; 63(6): 596-603, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32246509

RESUMO

INTRODUCTION: Allergic bronchopulmonary aspergillosis (ABPA) is a lung disease in patients with asthma or cystic fibrosis (CF) caused by chronic allergic inflammation to Aspergillus spp. antigens. The role of different immunological mediators in the formation of chronic allergic inflammation in patients with ABPA is not sufficiently explored. OBJECTIVES: This study aimed to investigate serum levels of thymic stromal lymphopoietin (TSLP), thymus and activated chemokine (TARC) as well as IL-8 in patients with ABPA, and to evaluate their diagnostic and monitoring value in the disease. PATIENTS/METHODS: Prospective study included 21 patients with ABPA, 25 patients with severe asthma with fungal sensitisation (SAFS), 37 patients with severe asthma without fungal sensitisation (SAwFS), and 16 healthy people. In patients with ABPA, the serum levels of biomarkers were determined at baseline and after 12 weeks of itraconazole therapy. Serum levels of total IgE, Aspergillus-fumigatus-specific IgE, TSLP, TARC, IL-8 were analysed by enzyme-linked immunosorbent assay. RESULTS: In patients with ABPA we established significantly higher serum levels of TARC, IL-8, total IgE, Aspergillus-fumigatus-specific IgE and peripheral blood eosinophil counts, compared to patients with SAwFS. There were no differences in TSLP levels between the examined groups of patients. Serum TARC levels were positively correlated to serum total IgE levels, A fumigatus-specific IgE levels and peripheral blood eosinophil counts and also negatively correlated to lung function (FEV1 ). Longitudinally, serum levels TARC, total IgE and peripheral blood eosinophil counts significant decreased after treatment of ABPA. CONCLUSION: Thymus and activated chemokine is a useful test in diagnosing and monitoring response to the antifungal treatment of patients with ABPA.


Assuntos
Aspergilose Broncopulmonar Alérgica/diagnóstico , Asma/complicações , Adulto , Anticorpos Antifúngicos/sangue , Aspergillus fumigatus , Biomarcadores/sangue , Quimiocina CCL17/sangue , Citocinas/sangue , Feminino , Humanos , Imunoglobulina E/sangue , Interleucina-18/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Escarro/microbiologia , Adulto Jovem , Linfopoietina do Estroma do Timo
4.
Microorganisms ; 11(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36677444

RESUMO

Metchnikovellids (Microsporidia: Metchnikovellida) are poorly studied hyperparasitic microsporidia that live in gregarines inhabiting the intestines of marine invertebrates, mostly polychaetes. Our recent studies showed that diversity of metchnikovellids might be significantly higher than previously thought, even within a single host. Four species of metchnikovellids were found in the gregarines inhabiting the gut of the polychaete Pygospio elegans from littoral populations of the White and Barents Seas: the eugregarine Polyrhabdina pygospionis is the host for Metchnikovella incurvata and M. spiralis, while the archigregarine Selenidium pygospionis is the host for M. dogieli and M. dobrovolskiji. The most common species in the White Sea is M. incurvata, while M. dobrovolskiji prevails in the Barents Sea. Gregarines within a single worm could be infected with different metchnikovellid species. However, co-infection of one and the same gregarine with several species of metchnikovellids has never been observed. The difference in prevalence and intensity of metchnikovellid invasion apparently depends on the features of the life cycle and on the development strategies of individual species.

5.
Drug Dev Ind Pharm ; 35(12): 1439-51, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19929203

RESUMO

BACKGROUND: With a view to the application in oral colon drug delivery systems, swelling and release behavior of synthesized interpolyelectrolyte complexes (IPEC) between sodium alginate and Eudragit EPO were investigated. METHOD: The microenvironmental changes in IPECs structure as a function of pH during swellability testing were investigated using FT-IR spectroscopy and elementary analysis. RESULTS: All samples of IPECs (Z = 0.66-1.25) during swelling were transformed to a similar structure with approximately the same composition. The release of the model drug diclofenac sodium was significantly delayed from matrices made up of the IPECs and independent from the composition of polycomplexes. CONCLUSION: According to the obtained results, these IPECs can be considered to have potential in colonic drug delivery as combined pH- and time-dependent systems.


Assuntos
Alginatos/química , Colo/metabolismo , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Eletrólitos/química , Ácidos Polimetacrílicos/química , Diclofenaco/administração & dosagem , Diclofenaco/química , Portadores de Fármacos/síntese química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Modelos Biológicos , Conformação Molecular , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos , Fatores de Tempo , Água/análise
6.
Asian Pac J Cancer Prev ; 18(1): 51-55, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28240009

RESUMO

Background: Cancer is one of the most common causes of human mortality, with about 14 million new cases and 8.2 million deaths reported in in 2012. Early diagnosis of cancer through screening allows interventions to reduce mortality. Fractal analysis of medical images may be useful for this purpose. Materials and Methods: In this study, we examined magnetic resonance (MR) images of healthy livers and livers containing metastases from colorectal cancer. The fractal dimension and the Hurst exponent were chosen as diagnostic features for tomographic imaging using Image J software package for image processings FracLac for applied for fractal analysis with a 120x150 pixel area. Calculations of the fractal dimensions of pathological and healthy tissue samples were performed using the box-counting method. Results: In pathological cases (foci formation), the Hurst exponent was less than 0.5 (the region of unstable statistical characteristics). For healthy tissue, the Hurst index is greater than 0.5 (the zone of stable characteristics). Conclusions: The study indicated the possibility of employing fractal rapid analysis for the detection of focal lesions of the liver. The Hurst exponent can be used as an important diagnostic characteristic for analysis of medical images.

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