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1.
Microorganisms ; 12(3)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38543649

RESUMO

Dry rot of potato tubers is a harmful disease caused by species of the Fusarium genus. Studies on the composition and features of Fusarium spp. that cause the disease in Russia are limited. Thirty-one Fusarium strains belonging to the F. sambucinum species complex (FSAMSC) and F. solani species complex (FSSC) were accurately identified using multilocus phylogenetic analysis of the tef and rpb2 loci, and their physiological characteristics were studied in detail. As a result, 21 strains of F. sambucinum s. str. and 1 strain of F. venenatum within the FSAMSC were identified. Among the analyzed strains within the FSSC, one strain of F. mori, four strains of F. noneumartii, and two strains of both F. stercicola and F. vanettenii species were identified. This is the first record of F. mori on potato as a novel host plant, and the first detection of F. noneumartii and F. stercicola species in Russia. The clear optimal temperature for the growth of the strains belonging to FSAMSC was noted to be 25 °C, with a growth rate of 11.6-15.0 mm/day, whereas, for the strains belonging to FSSC, the optimal temperature range was between 25 and 30 °C, with a growth rate of 5.5-14.1 mm/day. The distinctive ability of F. sambucinum strains to grow at 5 °C has been demonstrated. All analyzed Fusarium strains were pathogenic to potato cv. Gala and caused extensive damage of the tuber tissue at an incubation temperature of 23 °C for one month. Among the fungi belonging to the FSAMSC, the F. sambucinum strains were more aggressive and caused 23.9 ± 2.2 mm of necrosis in the tubers on average compared to the F. venenatum strain-17.7 ± 1.2 mm. Among the fungi belonging to the FSSC, the F. noneumartii strains were the most aggressive and caused 32.2 ± 0.8 mm of necrosis on average. The aggressiveness of the F. mori, F. stercicola, and especially the F. vanettenii strains was significantly lower: the average sizes of damage were 17.5 ± 0.5 mm, 17.2 ± 0.2 mm, and 12.5 ± 1.7 mm, respectively. At an incubation temperature of 5 °C, only the F. sambucinum strains caused tuber necroses in the range of 6.7 ± 0.5-15.9 ± 0.8 mm.

2.
Mycologia ; 115(6): 787-801, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37903077

RESUMO

A Fusarium species associated with sunflower based on multilocus genealogy, morphological, physiological, ecological, mating type, and mycotoxin production data is formally described as the newly discovered species Fusarium bilaiae. The F. bilaiae strains formed a genealogically exclusive lineage within the African clade of the F. fujikuroi species complex. Comparison of morphological characteristics of F. bilaiae strains with those of the closely related F. phyllophilum strain NRRL 13617 revealed similarities in the main micromorphology of both species: production of numerous one-celled microconidia in false heads and short chains on monophialides and polyphialides and the absence of macroconidia and sporodochia. There was a slight but significant distinction between the two species when the strains were grown on different agar media, as well as in the shape and width of microconidia. Fusarium bilaiae strains isolated from symptomatic sunflower were not pathogenic to members of the Asteraceae tested; apparently, they live as saprophytes or endophytes in sunflower tissues. A difference between the strains of the two species in the production of mycotoxins was demonstrated with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis. On autoclaved rice, F. bilaiae did not produce fumonisins and beauvericin but produced moniliformin, whereas F. phyllophilum produced all these mycotoxins. A polymerase chain reaction (PCR) assay specific for mating type alleles identified F. bilaiae as a putative heterothallic species with MAT1-1 and MAT1-2 idiomorphs, but laboratory crosses were unsuccessful. Determining the area and host range of the new endophytic species F. bilaiae is a priority for future research.


Assuntos
Asteraceae , Fusarium , Helianthus , Micotoxinas , Fusarium/genética , Espectrometria de Massas em Tandem
3.
Microbiol Resour Announc ; 11(7): e0125021, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35652634

RESUMO

Fusarium langsethiae is a suspected plant-pathogenic fungus causing cereal contamination with trichothecene mycotoxins. Here, we report the genome sequences of two F. langsethiae strains, MFG217701 (a prototroph) and MFG217702 (a biotin auxotroph), isolated from a grain of oat harvested in Russia.

4.
PeerJ ; 9: e12346, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34760369

RESUMO

The first appearance of Fusarium head blight (FHB)-and the beginning of scientific research of this disease-occurred the Far East region of Russia at the end of the 19th century. In the summer of 2019, in the Amur region, which comprises 60-70% of grain production in the Russian Far East, flooding caused a state of emergency. The quality of wheat and barley grains grown under natural conditions of FHB outbreaks, including grain infection, fungal species composition, DNA content of F. graminearum and chemotypes, and the presence of various mycotoxins, was studied. Fusarium infection rates reached extremely high percentages, 51-98%, the majority of which were F. graminearum infections. The amount of F. graminearum DNA in wheat grain samples was higher than in the barley grain samples and averaged 6.1 and 2.1 pg/ng, respectively. The content of deoxynivalenol (DON) in the wheat samples reached 13,343 ppb and in barley reached 7,755 ppb. A multilocus genotyping assay was conducted on the partially sequenced fragments of the translation elongation factor EF-1a, ammonium ligase gene, reductase gene, and 3-O-acetyltransferase gene in 29 Fusarium graminearum sensu lato strains from the grain harvested in the Amur region. All strains from the Far East region were characterized as F. graminearum sensu stricto; 70% were the 15-AcDON chemotype, while the other strains were the 3-AcDON chemotype. According to the results, after 140 years of study of FHB, we are still not very successful in controlling this disease if conditions are favorable for pathogen development. Even at present, some of the grain harvested must be destroyed, as high contamination of mycotoxins renders it unusable.

5.
Toxins (Basel) ; 13(10)2021 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-34678974

RESUMO

Alternaria fungi dominate the grain microbiota in many regions of the world; therefore, the detection of species that are able to produce mycotoxins has received much attention. A total of 178 grain samples of wheat, barley and oat obtained from the Urals and West Siberia regions of Russia in 2017-2019 were included in the study. Grain contamination with Alternaria fungi belonging to sections Alternaria and Infectoriae was analysed using qPCR with specific primers. The occurrence of four mycotoxins produced by Alternaria, AOH, AME, TEN, and TeA, was defined by HPLC-MS/MS. Alternaria DNA was found in all analysed grain samples. The prevalence of DNA of Alternaria sect. Alternaria fungi (range 53 × 10-4-21,731 × 10-4 pg/ng) over the DNA of Alternaria sect. Infectoriae (range 11 × 10-4‒4237 × 10-4 pg/ng) in the grain samples was revealed. Sixty-two percent of grain samples were contaminated by at least two Alternaria mycotoxins. The combination of TEN and TeA was found most often. Eight percent of grain samples were contaminated by all four mycotoxins, and only 3% of samples were free from the analysed secondary toxic metabolites. The amounts varied in a range of 2-53 µg/kg for AOH, 3-56 µg/kg for AME, 3-131 µg/kg for TEN and 9-15,000 µg/kg for TeA. To our knowledge, a new global maximum level of natural contamination of wheat grain with TeA was detected. A positive correlation between the amount of DNA from Alternaria sect. Alternaria and TeA was observed. The significant effects of cereal species and geographic origin of samples on the amounts of DNA and mycotoxins of Alternaria spp. in grain were revealed. Barley was the most heavily contaminated with fungi belonging to both sections. The content of AOH in oat grain was, on average, higher than that found in wheat and barley. The content of TEN in the grain of barley was lower than that in wheat and similar to that in oat. The content of TeA did not depend on the cereal crop. The effect of weather conditions (summer temperature and rainfall) on the final fungal and mycotoxin contamination of grain was discussed. The frequent co-occurrence of different Alternaria fungi and their mycotoxins in grain indicates the need for further studies investigating this issue.


Assuntos
Alternaria/isolamento & purificação , Grão Comestível/microbiologia , Micotoxinas/análise , Alternaria/genética , Avena/microbiologia , DNA Fúngico/isolamento & purificação , Contaminação de Alimentos/análise , Hordeum/microbiologia , Federação Russa , Triticum/microbiologia , Tempo (Meteorologia)
6.
Chem Biodivers ; 17(8): e2000294, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32421897

RESUMO

The biological characterization of Microdochium majus, M. nivale, and M. seminicola strains with wide geographical origins showed the diversity of their pathogenic properties and metabolite compounds, allowing them to exist in their habitats. Significant differences in the ability of Microdochium fungi to cause lesions on wheat and oat leaves were found. The intensity of symptoms depended on the species and substrate origin of the strains. On average M. seminicola strains were able to cause less leaf necrosis than M. majus and M. nivale. The volatile organic compound (VOC) profile of Microdochium fungi included 29 putative fungal metabolites. The spectrum of the identified VOCs in M. seminicola strains was much richer than that in M. majus and M. nivale strains. In addition, the strains of M. seminicola emitted at least six sesquiterpenes. Mycotoxin analysis by HPLC/MS/MS revealed that the analyzed Microdochium strains did not produce any toxic metabolites typically produced by filamentous fungi.


Assuntos
Ascomicetos/fisiologia , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Cromatografia Líquida de Alta Pressão/métodos , Micotoxinas/metabolismo , Doenças das Plantas/microbiologia , Espectrometria de Massas em Tandem/métodos , Compostos Orgânicos Voláteis/metabolismo
7.
Microorganisms ; 8(3)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121208

RESUMO

In total, 46 Microdochium strains from five different geographic regions of Russia were explored with respect to genetic diversity, morphology, and secondary metabolites. Based on the results of PCR, 59% and 28% of the strains were identified as M. nivale and M. majus, respectively. As a result of sequencing four genome regions, namely ITS, LSU, BTUB, and RPB2 (2778 bp), five genetically and phenotypically similar strains from Western Siberia were identified as M. seminicola, which, according to our findings, is the prevalent Microdochium species in this territory. This is the first record of M. seminicola in Russia. Attempts were made to distinguish between Microdochium species and to identify species-specific morphological characteristics in the anamorph and teleomorph stages and physiological properties. We examined the occurrence frequency of conidia with different numbers of septa in the strains of Microdochium. The predominance of three-septate macroconidia in M. majus was higher than that in M. nivale and typically exceeded 60% occurrence. Most M. majus and M. nivale strains formed walled protoperithecia on wheat stems. Only three strains of M. majus and one strain each of M. nivale and M. seminicola produced mature perithecia. The growth rate of M. seminicola strains was significantly lower on agar media at 5-25 °C than those of M. majus and M. nivale strains. Multimycotoxin analysis by HPLC-MS/MS revealed that the strains of three Microdochium species did not produce any toxic metabolites.

8.
Toxins (Basel) ; 11(5)2019 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060276

RESUMO

Wheat grains collected in three regions of Russia-Volga, Ural, and West Siberia-were analyzed for triangulation of methods in analysis of toxigenic Fusarium species. The presence of fungi and quantitative content of their biomass were detected by using various analytical methods, including a mycological and immunochemical methods, and quantitative PCR. Additionally, an enzyme-linked immunosorbent assay and high-performance liquid chromatography with tandem mass spectrometry were applied for determination of mycotoxins. Regional differences were found regarding the contamination of wheat grain by Fusarium fungi and their toxins. The most important observation was the detection of F. graminearum in the Ural and West Siberian regions, where this pathogen had not been found previously. A maximum damaged grains by F. graminearum and F. sporotrichioides was found in the grain samples from West Siberia. The DNA of F. graminearum was detected in 19.2% and DNA of F. sporotrichioides was found in 84.1% of the analyzed grain samples. The amount of Fusarium antigens in the grain samples from the West Siberian region was 7-8 times higher than in the grain samples from the other two regions. Significant contamination of the grain with deoxynivalenol and T-2/HT-2 toxins (maximum contents were 2239 ppb and 199 ppb, respectively) was detected in the West Siberian region.


Assuntos
Grão Comestível/microbiologia , Fusarium , Triticum/microbiologia , Antígenos de Fungos/análise , DNA Fúngico/análise , Grão Comestível/química , Monitoramento Ambiental , Contaminação de Alimentos/análise , Fusarium/genética , Micotoxinas/análise , Federação Russa , Triticum/química
9.
Metabolites ; 9(2)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717245

RESUMO

The common potato, Solanum tuberosum L., is the fourth most important agricultural crop worldwide. Until recently, vegetative propagation by tubers has been the main method of potato cultivation. A shift of interest to sexual potato reproduction by true botanical seeds is due to the appearance of a new hybrid seed breeding strategy whose successful application for many crop species has been supported by male sterility. This investigation was focused on the study of differences in the metabolite profiles of anthers at the mature pollen stage from male-fertile and male-sterile genotypes of S. tuberosum. Application of gas chromatography coupled with a mass spectrometry method allowed detection of metabolic profiles for 192 compounds. Further data analysis with several libraries fully identified 75 metabolites; a similar amount was defined up to the classes. Metabolic profiles in the anthers of fertile genotypes were significantly distinguished from male-sterile ones by the accumulation of carbohydrates, while the anthers of sterile genotypes contained a higher amount of amino acids. In comparison with male-fertile plants, male-sterile genotypes had undeveloped pollen grain characters; i.e., smaller grain size, a thicker exine, "permanent tetrads" that failed to disintegrate into microspores, and the absence of pollen apertures that might be due to a disorder in the metabolism of carbohydrates and fatty acids.

10.
Pathogens ; 7(4)2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30501049

RESUMO

Fusarium avenaceum and closely related species are common fungi on various plants, cultivated in different climatic regions. The aim of this study was to determine the taxonomic affiliations of the F. avenaceum, Fusarium arthrosporioides, and Fusarium anguioides strains by using morphological, physiological and molecular-genetic approaches. Twenty-six single-spored morphologically identified strains, which were mainly from cereals, were investigated in order to find out, if they belong to a separate species. Pathogenicity of strains to wheat seedlings and ISSR (Inter Simple Sequence Repeats) fingerprint and beta-tubulin DNA sequence patterns were analyzed. According to phylogenetic analyses, the strains could be divided into two big groups consisting of mostly F. avenaceum or F. anguioides strains. F. arthrosporioides was not detected as a separate species by the sum of the characters. F. anguioides was characterized as a separate species, which could be identified by morphological and molecular data. High genetic diversity of the F. avenaceum and related species was revealed. One F. anguioides strain (rudbeckia, Vladivostok, Russia), had an identical beta-tubulin sequence with two previously sequenced strains of Fusarium tricinctum species complex, which were isolated from dicotyledonous plants in Asia.

11.
Microorganisms ; 5(2)2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28362313

RESUMO

Analysis of 49 strains of Fusarium langsethiae originating from northern Europe (Russia, Finland, Sweden, UK, Norway, and Latvia) revealed the presence of spontaneous auxotrophic mutants that reflect natural intraspecific diversity. Our investigations detected that 49.0% of F. langsethiae strains were auxotrophic mutants for biotin, and 8.2% of the strains required thiamine as a growth factor. They failed to grow on vitamin-free media. For both prototrophic and auxotrophic strains, no growth defect was observed in rich organic media. Without essential vitamins, a significant reduction in the growth of the auxotrophic strains results in a decrease of the formation of T-2 toxin and diacetoxyscirpenol. In addition, all analysed F. langsethiae strains were distinguished into two subgroups based on PCR product sizes. According to our results, 26 and 23 strains of F. langsethiae belong to subgroups I and II respectively. We determined that the deletion in the intergenic spacer (IGS) region of the rDNA of F. langsethiae belonging to subgroup II is linked with temperature sensitivity and causes a decrease in strain growth at 30 °C. Four thiamine auxotrophic strains were found in subgroup I, while 21 biotin auxotrophic strains were detected in subgroups II. To the best of our knowledge, the spontaneous mutations in F. langsethiae observed in the present work have not been previously reported.

12.
Chem Biodivers ; 13(7): 891-903, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27253722

RESUMO

The compositions of volatile organic compounds (VOCs) emitted by Fusarium fungi (F. langsethiae, F. sibiricum, F. poae, and F. sporotrichioides) grown on two nutritive substrates: potato sucrose agar (PSA) and autoclaved wheat kernels (WK) were investigated. The culturing of fungi and study of their VOC emissions were performed in chromatographic vials at room temperature (23 - 24 °C) and the VOCs were sampled by a solid-phase microextraction on a 85 µm carboxen/polydimethylsiloxane fiber. GC/MS was performed using a 60-m HP-5 capillary column. Components of the VOC mixture were identified by electron impact mass spectra and chromatographic retention indices (RIs). The most abundant components of the VOC mixture emitted by Fusarium fungi are EtOH, AcOH, (i) BuOH, 3-methylbutan-1-ol, 2-methylbutan-1-ol, ethyl 3-methylbutanoate, terpenes with M 136, sesquiterpenes with M 204 (a total of about 25), and trichodiene. It was found that the strains grown on PSA emit a wider spectrum and larger amount of VOCs compared with those grown on wheat kernels. F. langsethiae strain is the most active VOC producer on both substrates. The use of SPME and GC/MS also offers the potential for differentiation of fungal species and strains.


Assuntos
Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Gases/análise , Compostos Orgânicos Voláteis/análise , Ágar/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Gases/química , Gases/metabolismo , Sementes/metabolismo , Solanum tuberosum/química , Microextração em Fase Sólida , Sacarose/metabolismo , Triticum , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Volatilização
13.
Environ Microbiol Rep ; 7(4): 623-33, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25990300

RESUMO

'Bacterial consortium' sensu lato applies to mutualism or syntrophy-based systems consisting of unrelated bacteria. Consortia of cyanobacteria have been preferentially studied on Anabaena epibioses; non-photosynthetic satellites of other filamentous or unicellular cyanobacteria were also considered although structure-functional data are few. At the same time, information about consortia of cyanobacteria which have light-harvesting antennae distinct from standard phycobilisome was missing. In this study, we characterized first, via a polyphasic approach, the cultivable consortium of Prochlorothrix hollandica CCAP 1490/1 (filamentous cyanobacterium which contains chlorophylls a, b/carotenoid/protein complex in the absence of phycobilisome) and non-photosynthetic heterotrophic bacteria. The strains of most abundant satellites were isolated and identified. Consortium metagenome reconstructed via 454-pyro and Illumina sequencing was shown to include, except for P. hollandica, several phylotypes of Proteobacteria and Bacteroidetes. The ratio of consortium members was essentially stable irrespective of culture age, and restored after artificially imposed imbalance. The consortium had a complex spatial arrangement as demonstrated by FISH and SEM images of the association, epibiosis, and biofilm type. Preliminary data of metagenome annotation agreed with the hypothesis that satellite bacteria contribute to P. hollandica protection from reactive oxygen species (ROS).


Assuntos
Bacteroidetes/classificação , Biota , Metagenoma , Consórcios Microbianos , Prochlorothrix/crescimento & desenvolvimento , Proteobactérias/classificação , Bacteroidetes/genética , Bacteroidetes/crescimento & desenvolvimento , Bacteroidetes/isolamento & purificação , Análise por Conglomerados , Hibridização in Situ Fluorescente , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Filogenia , Prochlorothrix/genética , Proteobactérias/genética , Proteobactérias/crescimento & desenvolvimento , Proteobactérias/isolamento & purificação , Análise de Sequência de DNA
14.
Sci Total Environ ; 524-525: 400-15, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25930241

RESUMO

The main wastes of the Estonian shale oil industry - oil shale semi-coke and ashes - are deposited in landfills. The Kohtla-Järve oil shale semi-coke and ash landfill, which is likely the largest of its kind in the World, was started in 1938. The environmental risks connected with the landfill were assessed and prioritized. The most significant hazard to human health is emission of harmful landfill gases and the water contamination in the local river network is harmful for aqueous organisms. The spatial expansion of subsurface contamination predicted by the groundwater transport model completed is practically insignificant from the viewpoint of health services. The landfill's leachates must be captured and purified, and the closed part of the landfill should be covered by greenery. The partial landfill capping recently executed is useless. The EU Landfill Directive requirements imposed on the hydraulic resistance of geological barriers cannot prevent the leakage of contaminants from a landfill.


Assuntos
Indústria de Petróleo e Gás , Eliminação de Resíduos/métodos , Instalações de Eliminação de Resíduos , Coque/análise , Monitoramento Ambiental , Estônia , Petróleo/análise , Poluentes Químicos da Água
15.
J Craniofac Surg ; 24(1): e15-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23348321

RESUMO

Development, progression, and therapy of periimplantitis are nonresolved emerging problems. The aim of this pilot study was to establish a model for periimplantitis in mice to have a base for tests with immune-deficient knockout organisms to improve the knowledge about development and progression of periimplantitis and to develop further therapeutic options.In 8 mice, titanium implants were inserted in the median of the palate. Four of these implants had ligatures (periimplantitis group). After 2 weeks, the animals received a special diet enriched with sugar and flavor. After 9 weeks, micro-computed tomography (micro-CT) examinations to evaluate the periimplant tissue and histologies were performed.Dental implant insertions within the oral cavity are possible in living mice. Implants with ligatures showed significantly larger periimplant bone defects than controls. The radiologic findings were confirmed by histology. At the end of the observation period, the portion of implants lost was higher in the ligature group.This is the first publication to describe the insertion of dental implants in living mice. In addition, it is the first time that periimplant infection could be induced in that species. This model will pave the way to study knockout mice with reduced or even enhanced resistance to periimplantitis.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Peri-Implantite/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Ligadura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Projetos Piloto , Titânio , Microtomografia por Raio-X
16.
Gut ; 62(4): 520-30, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22442160

RESUMO

OBJECTIVE: Cathepsin K is a lysosomal cysteine protease that has pleiotropic roles in bone resorption, arthritis, atherosclerosis, blood pressure regulation, obesity and cancer. Recently, it was demonstrated that cathepsin K-deficient (Ctsk(-/-) ) mice are less susceptible to experimental autoimmune arthritis and encephalomyelitis, which implies a functional role for cathepsin K in chronic inflammatory responses. Here, the authors address the relevance of cathepsin K in the intestinal immune response during chronic intestinal inflammation. DESIGN: Chronic colitis was induced by administration of 2% dextran sodium sulphate (DSS) in distilled water. Mice were assessed for disease severity, histopathology and endoscopic appearance. Furthermore, DSS-exposed Ctsk(-/-) mice were treated by rectal administration of recombinant cathepsin K. Intestinal microflora was assessed by real-time PCR and 16srDNA molecular fingerprinting of ileal and colonic mucosal and faecal samples. RESULTS: Using Ctsk(-/-) mice, the authors demonstrate a protective role of cathepsin K against chronic DSS colitis. Dissecting the underlying mechanisms the authors found cathepsin K to be present in intestinal goblet cells and the mucin layer. Furthermore, a direct cathepsin K-mediated bactericidal activity against intestinal bacteria was demonstrated, which potentially explains the alteration of intestinal microbiota observed in Ctsk(-/-) mice. Rectal administration of recombinant cathepsin K in DSS-treated Ctsk(-/-) mice ameliorates the severity of intestinal inflammation. CONCLUSION: These data identify extracellular cathepsin K as an intestinal antibacterial factor with anti-inflammatory potential and suggest that topical administration of cathepsin K might provide a therapeutic option for patients with inflammatory bowel disease.


Assuntos
Catepsina K/farmacologia , Colite/tratamento farmacológico , Colite/microbiologia , Animais , Western Blotting , Catepsina K/metabolismo , Colite/induzido quimicamente , Colite/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Endoscopia Gastrointestinal , Ensaio de Imunoadsorção Enzimática , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real
17.
PLoS One ; 7(3): e30985, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22427801

RESUMO

The c-Jun N-terminal kinase (JNK)-inhibiting peptide D-JNKI-1, syn. XG-102 was tested for its therapeutic potential in acute inflammatory bowel disease (IBD) in mice. Rectal instillation of the chemical irritant trinitrobenzene sulfonic acid (TNBS) provoked a dramatic acute inflammation in the colon of 7-9 weeks old mice. Coincident subcutaneous application of 100 µg/kg XG-102 significantly reduced the loss of body weight, rectal bleeding and diarrhoea. After 72 h, the end of the study, the colon was removed and immuno-histochemically analysed. XG-102 significantly reduced (i) pathological changes such as ulceration or crypt deformation, (ii) immune cell pathology such as infiltration and presence of CD3- and CD68-positive cells, (iii) the production of tumor necrosis factor (TNF)-α in colon tissue cultures from TNBS-treated mice, (iv) expression of Bim, Bax, FasL, p53, and activation of caspase 3, (v) complexation of JNK2 and Bim, and (vi) expression and activation of the JNK substrate and transcription factor c-Jun. A single application of subcutaneous XG-102 was at least as effective or even better depending on the outcome parameter as the daily oral application of sulfasalazine used for treatment of IBD.The successful and substantial reduction of the severe, TNBS-evoked intestinal damages and clinical symptoms render the JNK-inhibiting peptide XG-102 a powerful therapeutic principle of IBD.


Assuntos
Apoptose/efeitos dos fármacos , Colite Ulcerativa/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Peptídeos/farmacologia , Análise de Variância , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Western Blotting , Complexo CD3/metabolismo , Caspase 3/metabolismo , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/patologia , Proteína Ligante Fas/metabolismo , Imunofluorescência , Imuno-Histoquímica , Imunoprecipitação , Proteínas de Membrana/metabolismo , Camundongos , Peptídeos/uso terapêutico , Proteínas Proto-Oncogênicas/metabolismo , Ácido Trinitrobenzenossulfônico/toxicidade , Fator de Necrose Tumoral alfa/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Redução de Peso/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
18.
Eur J Protistol ; 48(2): 149-59, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21700436

RESUMO

Paramecium bursaria Chlorella viruses were observed by applying transmission electron microscopy in the native symbiotic system Paramecium bursaria (Ciliophora, Oligohymenophorea) and the green algae Chlorella (Chlorellaceae, Trebouxiophyceae). Virus particles were abundant and localized in the ciliary pits of the cortex and in the buccal cavity of P. bursaria. This was shown for two types of the symbiotic systems associated with two types of Chlorella viruses - Pbi or NC64A. A novel quantitative stereological approach was applied to test whether virus particles were distributed randomly on the Paramecium surface or preferentially occupied certain zones. The ability of the virus to form an association with the ciliate was investigated experimentally; virus particles were mixed with P. bursaria or with symbiont-free species P. caudatum. Our results confirmed that in the freshwater ecosystems two types of P. bursaria -Chlorella symbiotic systems exist, those without Chlorella viruses and those associated with a large amount of the viruses. The fate of Chlorella virus particles at the Paramecium surface was determined based on obtained statistical data and taking into account ciliate feeding currents and cortical reorganization during cell division. A life cycle of the viruses in the complete symbiotic system is proposed.


Assuntos
Chlorella/virologia , Paramecium/ultraestrutura , Paramecium/virologia , Vírion/ultraestrutura , Microscopia Eletrônica de Transmissão , Paramecium/parasitologia , Vírion/fisiologia , Ligação Viral
19.
BMC Genomics ; 12: 305, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21663663

RESUMO

BACKGROUND: The intestinal mucosa is characterized by complex metabolic and immunological processes driven highly dynamic gene expression programs. With the advent of next generation sequencing and its utilization for the analysis of the RNA sequence space, the level of detail on the global architecture of the transcriptome reached a new order of magnitude compared to microarrays. RESULTS: We report the ultra-deep characterization of the polyadenylated transcriptome in two closely related, yet distinct regions of the mouse intestinal tract (small intestine and colon). We assessed tissue-specific transcriptomal architecture and the presence of novel transcriptionally active regions (nTARs). In the first step, signatures of 20,541 NCBI RefSeq transcripts could be identified in the intestine (74.1% of annotated genes), thereof 16,742 are common in both tissues. Although the majority of reads could be linked to annotated genes, 27,543 nTARs not consistent with current gene annotations in RefSeq or ENSEMBL were identified. By use of a second independent strand-specific RNA-Seq protocol, 20,966 of these nTARs were confirmed, most of them in vicinity of known genes. We further categorized our findings by their relative adjacency to described exonic elements and investigated regional differences of novel transcribed elements in small intestine and colon. CONCLUSIONS: The current study demonstrates the complexity of an archetypal mammalian intestinal mRNA transcriptome in high resolution and identifies novel transcriptionally active regions at strand-specific, single base resolution. Our analysis for the first time shows a strand-specific comparative picture of nTARs in two tissues and represents a resource for further investigating the transcriptional processes that contribute to tissue identity.


Assuntos
Mucosa Intestinal/metabolismo , RNA Antissenso/genética , Análise de Sequência de RNA/métodos , Transcrição Gênica/genética , Animais , Benchmarking , Perfilação da Expressão Gênica , Intestinos/citologia , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade de Órgãos
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