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Pesquisa : D13.444.735.650 [Categoria DeCS]
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  1 / 3333 MEDLINE  
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[PMID]:28745426
[Au] Autor:Tomada S; Sonego P; Moretto M; Engelen K; Pertot I; Perazzolli M; Puopolo G
[Ad] Endereço:Department of Sustainable Agro-Ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach (FEM), San Michele all'Adige, Italy.
[Ti] Título:Dual RNA-Seq of Lysobacter capsici AZ78 - Phytophthora infestans interaction shows the implementation of attack strategies by the bacterium and unsuccessful oomycete defense responses.
[So] Source:Environ Microbiol;19(10):4113-4125, 2017 Oct.
[Is] ISSN:1462-2920
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Biological interactions in the microbial communities of the rhizosphere continuously shape the gene expression patterns of each individual microorganism. A dual RNA-Seq approach was applied to obtain a comprehensive overview of the molecular mechanisms activated during the interaction between the biocontrol rhizobacterium Lysobacter capsici AZ78 and the soilborne phytopathogenic oomycete Phytophthora infestans. The RNA-Seq transcriptional profile of L. capsici AZ78 was characterized by up-regulation of genes concerned in the biogenesis of type 4 pilus and lytic enzymes, involved, respectively, in host colonization and subsequent attack of the P. infestans cell wall. The activation of detoxification processes allowed L. capsici AZ78 to overcome the attempted defense processes of P. infestans. Moreover, the genes involved in antibiotic biosynthesis were up-regulated in L. capsici AZ78 and caused cell death in P. infestans, with the activation of putative apoptotic processes. The consequences of P. infestans cell death resulted in the down-regulation of primary metabolic pathways, such as carbohydrates, nucleic acids and protein metabolisms. Overall, the mechanism of action of L. capsici AZ78 was related to parasitism and predatory activities that cause the death of P. infestans.
[Mh] Termos MeSH primário: Agentes de Controle Biológico
Lysobacter/genética
Lysobacter/patogenicidade
Phytophthora infestans/genética
Phytophthora infestans/microbiologia
RNA Bacteriano/genética
RNA de Protozoário/genética
[Mh] Termos MeSH secundário: Sequência de Bases
Regulação da Expressão Gênica/genética
Doenças das Plantas/parasitologia
Raízes de Plantas/microbiologia
Raízes de Plantas/parasitologia
Análise de Sequência de RNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biological Control Agents); 0 (RNA, Bacterial); 0 (RNA, Protozoan)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1111/1462-2920.13861


  2 / 3333 MEDLINE  
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[PMID]:28459502
[Au] Autor:Kim KS; Jung JH; Min GS
[Ad] Endereço:Department of Biological Sciences, Inha University, 100 Inha-ro, Nam-gu, Incheon, 22212, South Korea.
[Ti] Título:Morphology and Molecular Phylogeny of Two New Ciliates, Holostichides heterotypicus n. sp. and Holosticha muuiensis n. sp. (Ciliophora: Urostylida).
[So] Source:J Eukaryot Microbiol;64(6):873-884, 2017 Nov.
[Is] ISSN:1550-7408
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Two new urostylid species, Holostichides heterotypicus n. sp. and Holosticha muuiensis n. sp., were discovered in South Korea. Morphological and phylogenetic analyses were carried out to confirm that these species are new to science. Holostichides heterotypicus is mainly characterized by the following combination of features: 110-205 µm long in vivo; 5-10 frontoterminal cirri; 6-8 midventral pairs with 2-3 midventral cirral rows; cortical granules present; four bipolar dorsal kineties; and 6-9 caudal cirri. Ontogenetic features of H. heterotypicus are similar to those of H. typicus. Phylogenetic analyses revealed that H. heterotypicus was distantly separated from bakuellid genera Apobakuella, Bakuella, Metaurostylopsis, and Neobakuella. This result is supported by the following features: transverse cirri (present in the other four bakuellids vs. absent in Holostichides) and caudal cirri (absent in the other four bakuellids vs. present in Holostichides). Holosticha muuiensis n. sp. is mainly distinguished from its congeners by the following combination of features: 100-185 long in vivo; shortened undulating membrane; cortical granules lacking; contractile vacuole absent; 51-66 adoral zone of membranelles; 42-60 macronuclear nodules; and five bipolar dorsal kineties. In the phylogenetic tree, Holosticha muuiensis n. sp. clustered with a Holosticha group (containing Holosticha diademata, Holosticha foissneri, and Holosticha heterofoissneri).
[Mh] Termos MeSH primário: Cilióforos/classificação
Filogenia
[Mh] Termos MeSH secundário: Cilióforos/citologia
Cilióforos/genética
Cilióforos/isolamento & purificação
Análise por Conglomerados
DNA de Protozoário/química
DNA de Protozoário/genética
DNA Ribossômico/química
DNA Ribossômico/genética
Genes de RNAr
Microscopia
RNA de Protozoário/genética
RNA Ribossômico 18S/genética
República da Coreia
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Protozoan); 0 (DNA, Ribosomal); 0 (RNA, Protozoan); 0 (RNA, Ribosomal, 18S)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1111/jeu.12421


  3 / 3333 MEDLINE  
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[PMID]:28450531
[Au] Autor:Lindblad KA; Bracht JR; Williams AE; Landweber LF
[Ad] Endereço:Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA.
[Ti] Título:Thousands of RNA-cached copies of whole chromosomes are present in the ciliate during development.
[So] Source:RNA;23(8):1200-1208, 2017 08.
[Is] ISSN:1469-9001
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The ciliate maintains two genomes: a germline genome that is active only during sexual conjugation and a transcriptionally active, somatic genome that derives from the germline via extensive sequence reduction and rearrangement. Previously, we found that long noncoding (lnc) RNA "templates"-telomere-containing, RNA-cached copies of mature chromosomes-provide the information to program the rearrangement process. Here we used a modified RNA-seq approach to conduct the first genome-wide search for endogenous, telomere-to-telomere RNA transcripts. We find that during development, produces long noncoding RNA copies for over 10,000 of its 16,000 somatic chromosomes, consistent with a model in which transmits an RNA-cached copy of its somatic genome to the sexual progeny. Both the primary sequence and expression profile of a somatic chromosome influence the temporal distribution and abundance of individual template RNAs. This suggests that may undergo multiple rounds of DNA rearrangement during development. These observations implicate a complex set of thousands of long RNA molecules in the wiring and maintenance of a highly elaborate somatic genome architecture.
[Mh] Termos MeSH primário: Cromossomos/genética
Genoma de Protozoário/genética
Oxytricha/genética
RNA Longo não Codificante/genética
RNA de Protozoário/genética
[Mh] Termos MeSH secundário: Animais
Variações do Número de Cópias de DNA
Sequenciamento de Nucleotídeos em Larga Escala/métodos
Oxytricha/crescimento & desenvolvimento
Telômero/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (RNA, Long Noncoding); 0 (RNA, Protozoan)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171223
[Lr] Data última revisão:
171223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1261/rna.058511.116


  4 / 3333 MEDLINE  
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[PMID]:28968395
[Au] Autor:Chua TH; Manin BO; Daim S; Vythilingam I; Drakeley C
[Ad] Endereço:Department of Pathobiology and Medical Diagnostics, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia.
[Ti] Título:Phylogenetic analysis of simian Plasmodium spp. infecting Anopheles balabacensis Baisas in Sabah, Malaysia.
[So] Source:PLoS Negl Trop Dis;11(10):e0005991, 2017 Oct.
[Is] ISSN:1935-2735
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Anopheles balabacensis of the Leucospyrus group has been confirmed as the primary knowlesi malaria vector in Sabah, Malaysian Borneo for some time now. Presently, knowlesi malaria is the only zoonotic simian malaria in Malaysia with a high prevalence recorded in the states of Sabah and Sarawak. METHODOLOGY/PRINCIPAL FINDINGS: Anopheles spp. were sampled using human landing catch (HLC) method at Paradason village in Kudat district of Sabah. The collected Anopheles were identified morphologically and then subjected to total DNA extraction and polymerase chain reaction (PCR) to detect Plasmodium parasites in the mosquitoes. Identification of Plasmodium spp. was confirmed by sequencing the SSU rRNA gene with species specific primers. MEGA4 software was then used to analyse the SSU rRNA sequences and bulid the phylogenetic tree for inferring the relationship between simian malaria parasites in Sabah. PCR results showed that only 1.61% (23/1,425) of the screened An. balabacensis were infected with one or two of the five simian Plasmodium spp. found in Sabah, viz. Plasmodium coatneyi, P. inui, P. fieldi, P. cynomolgi and P. knowlesi. Sequence analysis of SSU rRNA of Plasmodium isolates showed high percentage of identity within the same Plasmodium sp. group. The phylogenetic tree based on the consensus sequences of P. knowlesi showed 99.7%-100.0% nucleotide identity among the isolates from An. balabacensis, human patients and a long-tailed macaque from the same locality. CONCLUSIONS/SIGNIFICANCE: This is the first study showing high molecular identity between the P. knowlesi isolates from An. balabacensis, human patients and a long-tailed macaque in Sabah. The other common simian Plasmodium spp. found in long-tailed macaques and also detected in An. balabacensis were P. coatneyi, P. inui, P. fieldi and P. cynomolgi. The high percentage identity of nucleotide sequences between the P. knowlesi isolates from the long-tailed macaque, An. balabacensis and human patients suggests a close genetic relationship between the parasites from these hosts.
[Mh] Termos MeSH primário: Anopheles/parasitologia
Doenças dos Macacos/parasitologia
Plasmodium knowlesi/classificação
Plasmodium knowlesi/genética
[Mh] Termos MeSH secundário: Animais
DNA de Protozoário/genética
Genes de RNAr
Macaca fascicularis/parasitologia
Malária/epidemiologia
Malária/parasitologia
Malária/transmissão
Malária/veterinária
Malásia/epidemiologia
Filogenia
Reação em Cadeia da Polimerase
RNA de Protozoário/genética
RNA Ribossômico/genética
Zoonoses/epidemiologia
Zoonoses/parasitologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Protozoan); 0 (RNA, Protozoan); 0 (RNA, Ribosomal)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171003
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pntd.0005991


  5 / 3333 MEDLINE  
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[PMID]:28840814
[Au] Autor:Boscaro V; James ER; Fiorito R; Hehenberger E; Karnkowska A; Del Campo J; Kolisko M; Irwin NAT; Mathur V; Scheffrahn RH; Keeling PJ
[Ad] Endereço:1​Department of Botany, University of British Columbia, Vancouver, BC, Canada.
[Ti] Título:Molecular characterization and phylogeny of four new species of the genus Trichonympha (Parabasalia, Trichonymphea) from lower termite hindguts.
[So] Source:Int J Syst Evol Microbiol;67(9):3570-3575, 2017 Sep.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Members of the genus Trichonympha are among the most well-known, recognizable and widely distributed parabasalian symbionts of lower termites and the wood-eating cockroach species of the genus Cryptocercus. Nevertheless, the species diversity of this genus is largely unknown. Molecular data have shown that the superficial morphological similarities traditionally used to identify species are inadequate, and have challenged the view that the same species of the genus Trichonympha can occur in many different host species. Ambiguities in the literature, uncertainty in identification of both symbiont and host, and incomplete samplings are limiting our understanding of the systematics, ecology and evolution of this taxon. Here we describe four closely related novel species of the genus Trichonympha collected from South American and Australian lower termites: Trichonympha hueyi sp. nov. from Rugitermes laticollis, Trichonympha deweyi sp. nov. from Glyptotermes brevicornis, Trichonympha louiei sp. nov. from Calcaritermes temnocephalus and Trichonympha webbyae sp. nov. from Rugitermes bicolor. We provide molecular barcodes to identify both the symbionts and their hosts, and infer the phylogeny of the genus Trichonympha based on small subunit rRNA gene sequences. The analysis confirms the considerable divergence of symbionts of members of the genus Cryptocercus, and shows that the two clades of the genus Trichonympha harboured by termites reflect only in part the phylogeny of their hosts.
[Mh] Termos MeSH primário: Sistema Digestório/microbiologia
Hypermastigia/classificação
Isópteros/microbiologia
Filogenia
[Mh] Termos MeSH secundário: Animais
Austrália
Composição de Bases
Equador
Hypermastigia/genética
Hypermastigia/isolamento & purificação
Peru
RNA de Protozoário/genética
RNA Ribossômico/genética
Análise de Sequência de DNA
Simbiose
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Protozoan); 0 (RNA, Ribosomal)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170826
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002169


  6 / 3333 MEDLINE  
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[PMID]:28803569
[Au] Autor:Chen XR; Ye LI; Fan JW; Li C; Tang F; Liu W; Ren LZ; Bai JY
[Ad] Endereço:Jilin Provincial Key Laboratory of Animal Embryo Engineering,College of Animal Sciences,Jilin University,Changchun,P. R. China.
[Ti] Título:Detection of Kobe-type and Otsu-type Babesia microti in wild rodents in China's Yunnan province.
[So] Source:Epidemiol Infect;145(13):2704-2710, 2017 10.
[Is] ISSN:1469-4409
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Babesiosis is an emerging tick-transmitted zoonosis prevalent in large parts of the world. This study was designed to determine the rates of Babesia microti infection among small rodents in Yunnan province, where human cases of babesiosis have been reported. Currently, distribution of Babesia in its endemic regions is largely unknown. In this study, we cataloged 1672 small wild rodents, comprising 4 orders, from nine areas in western Yunnan province between 2009 and 2011. Babesia microti DNA was detected by polymerase chain reaction in 4·3% (72/1672) of the rodents analyzed. The most frequently infected rodent species included Apodemus chevrieri and Niviventer fulvescens. Rodents from forests and shrublands had significantly higher Babesia infection rates. Genetic comparisons revealed that Babesia was most similar to the Kobe- and Otsu-type strains identified in Japan. A variety of rodent species might be involved in the enzootic maintenance and transmission of B. microti, supporting the need for further serological investigations in humans.
[Mh] Termos MeSH primário: Babesia microti/isolamento & purificação
Babesiose/epidemiologia
Doenças dos Roedores/epidemiologia
[Mh] Termos MeSH secundário: Animais
Babesia microti/genética
Babesiose/diagnóstico
Babesiose/parasitologia
China/epidemiologia
Filogenia
Reação em Cadeia da Polimerase/veterinária
RNA de Protozoário/genética
RNA Ribossômico 18S/genética
Doenças dos Roedores/parasitologia
Análise de Sequência de RNA/veterinária
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (RNA, Protozoan); 0 (RNA, Ribosomal, 18S)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171125
[Lr] Data última revisão:
171125
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170815
[St] Status:MEDLINE
[do] DOI:10.1017/S0950268817001686


  7 / 3333 MEDLINE  
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[PMID]:28802260
[Au] Autor:McDermott SM; Stuart K
[Ad] Endereço:Center for Infectious Disease Research (formerly Seattle BioMed), Seattle, Washington 98109, USA.
[Ti] Título:The essential functions of KREPB4 are developmentally distinct and required for endonuclease association with editosomes.
[So] Source:RNA;23(11):1672-1684, 2017 Nov.
[Is] ISSN:1469-9001
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Uridine insertion and deletion RNA editing generates functional mitochondrial mRNAs in , and several transcripts are differentially edited in bloodstream (BF) and procyclic form (PF) cells correlating with changes in mitochondrial function. Editing is catalyzed by three ∼20S editosomes that have a common set of 12 proteins, but are typified by mutually exclusive RNase III KREN1, N2, and N3 endonucleases with distinct cleavage specificities. KREPB4 is a common editosome protein that has a degenerate RNase III domain lacking conserved catalytic residues, in addition to zinc-finger and Pumilio/fem-3 mRNA binding factor (PUF) motifs. Here we show that KREPB4 is essential for BF and PF growth, in vivo RNA editing, and editosome integrity, but that loss of KREPB4 has differential effects on editosome components and complexes between BF and PF cells. We used targeted mutagenesis to investigate the functions of the conserved PUF and RNase III domains in both life-cycle stages and show that the PUF motif is not essential for function in BF or PF. In contrast, specific mutations in the RNase III domain severely inhibit BF and PF growth and editing, and disrupt ∼20S editosomes, while others indicate that the RNase III domain is noncatalytic. We further show that KREPB4, specifically the noncatalytic RNase III domain, is required for the association of KREN1, N2, and N3 with PF editosomes. These results, combined with previous studies, support a model in which KREPB4 acts as a pseudoenzyme to form the noncatalytic half of an RNase III heterodimer with the editing endonucleases.
[Mh] Termos MeSH primário: Proteínas de Protozoários/metabolismo
Edição de RNA
Proteínas de Ligação a RNA/metabolismo
Trypanosoma brucei brucei/metabolismo
[Mh] Termos MeSH secundário: Endonucleases/metabolismo
Técnicas de Silenciamento de Genes
Genes de Protozoários
Modelos Biológicos
Mutação
Domínios Proteicos
Proteínas de Protozoários/química
Proteínas de Protozoários/genética
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
RNA de Protozoário/genética
RNA de Protozoário/metabolismo
Proteínas de Ligação a RNA/química
Proteínas de Ligação a RNA/genética
Ribonuclease III/química
Ribonuclease III/genética
Ribonuclease III/metabolismo
Trypanosoma brucei brucei/genética
Trypanosoma brucei brucei/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Protozoan Proteins); 0 (RNA, Messenger); 0 (RNA, Protozoan); 0 (RNA-Binding Proteins); 0 (mitochondrial messenger RNA); EC 3.1.- (Endonucleases); EC 3.1.26.3 (Ribonuclease III)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170813
[St] Status:MEDLINE
[do] DOI:10.1261/rna.062786.117


  8 / 3333 MEDLINE  
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[PMID]:28719294
[Au] Autor:Tadesse FG; Lanke K; Nebie I; Schildkraut JA; Gonçalves BP; Tiono AB; Sauerwein R; Drakeley C; Bousema T; Rijpma SR
[Ad] Endereço:Armauer Hansen Research Institute (AHRI), Addis Ababa, Ethiopia.
[Ti] Título:Molecular Markers for Sensitive Detection of Asexual Stage Parasites and their Application in a Malaria Clinical Trial.
[So] Source:Am J Trop Med Hyg;97(1):188-198, 2017 Jul.
[Is] ISSN:1476-1645
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:parasite life stages respond differently to antimalarial drugs. Sensitive stage-specific molecular assays may help to examine parasite dynamics at microscopically detectable and submicroscopic parasite densities in epidemiological and clinical studies. In this study, we compared the performance of skeleton-binding protein 1 (SBP1), ring-infected erythrocyte surface antigen, Hyp8, ring-exported protein 1 (REX1), and PHISTb mRNA for detecting ring-stage trophozoite-specific transcripts using quantitative reverse transcriptase polymerase chain reaction. Markers were tested on tightly synchronized in vitro parasites and clinical trial samples alongside established markers of parasite density (18S DNA and rRNA) and gametocyte density (Pfs25 mRNA). SBP1 was the most sensitive marker but showed low-level expression in mature gametocytes. Novel markers REX1 and PHISTb showed lower sensitivity but higher specificity for ring-stage trophozoites. Using in vivo clinical trial samples from gametocyte-negative patients, we observed evidence of persisting trophozoite transcripts for at least 14 days postinitiation of treatment. It is currently not clear if these transcripts represent viable parasites that may have implications for clinical treatment outcome or transmission potential.
[Mh] Termos MeSH primário: Malária Falciparum/sangue
Malária Falciparum/parasitologia
Plasmodium falciparum/isolamento & purificação
[Mh] Termos MeSH secundário: Antimaláricos/uso terapêutico
Artemisininas/administração & dosagem
Artemisininas/uso terapêutico
Biomarcadores/sangue
Burkina Faso/epidemiologia
DNA de Protozoário/genética
Método Duplo-Cego
Combinação de Medicamentos
Etanolaminas/administração & dosagem
Etanolaminas/uso terapêutico
Fluorenos/administração & dosagem
Fluorenos/uso terapêutico
Seres Humanos
Malária Falciparum/tratamento farmacológico
Malária Falciparum/epidemiologia
Plasmodium falciparum/genética
Primaquina/administração & dosagem
Primaquina/uso terapêutico
RNA de Protozoário/genética
RNA Ribossômico 18S/genética
RNA Ribossômico 18S/isolamento & purificação
Trofozoítos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL
[Nm] Nome de substância:
0 (Antimalarials); 0 (Artemisinins); 0 (Biomarkers); 0 (DNA, Protozoan); 0 (Drug Combinations); 0 (Ethanolamines); 0 (Fluorenes); 0 (RNA, Protozoan); 0 (RNA, Ribosomal, 18S); 0 (artemether-lumefantrine combination); MVR3634GX1 (Primaquine)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170731
[Lr] Data última revisão:
170731
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170719
[St] Status:MEDLINE
[do] DOI:10.4269/ajtmh.16-0893


  9 / 3333 MEDLINE  
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[PMID]:28704426
[Au] Autor:Azizi H; Romão TP; Santos Charret K; Padmanabhan PK; de Melo Neto OP; Müller-McNicoll M; Papadopoulou B
[Ad] Endereço:Research Center in Infectious Diseases, CHU de Quebec Research Center-University Laval, Quebec, QC. Canada.
[Ti] Título:RNA secondary structure and nucleotide composition of the conserved hallmark sequence of Leishmania SIDER2 retroposons are essential for endonucleolytic cleavage and mRNA degradation.
[So] Source:PLoS One;12(7):e0180678, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We have reported previously that Short Interspersed Degenerate Retroposons of the SIDER2 subfamily, largely located within 3'UTRs of Leishmania transcripts, promote rapid turnover of mRNAs through endonucleolytic cleavage within the highly conserved second tandem 79-nt hallmark sequence (79-nt SII). Here, we used site-directed mutagenesis and in silico RNA structural studies to delineate the cis-acting requirements within 79-nt SII for cleavage and mRNA degradation. The putative cleavage site(s) and other nucleotides predicted to alter the RNA secondary structure of 79-nt SII were either deleted or mutated and their effect on mRNA turnover was monitored using a gene reporter system. We found that short deletions of 8-nt spanning the two predicted cleavage sites block degradation of SIDER2-containing transcripts, leading to mRNA accumulation. Furthermore, single or double substitutions of the dinucleotides targeted for cleavage as well as mutations altering the predicted RNA secondary structure encompassing both cleavage sites also prevent mRNA degradation, confirming that these dinucleotides are the bona fide cleavage sites. In line with these results, we show that stage-regulated SIDER2 inactivation correlates with the absence of endonucleolytic cleavage. Overall, these data demonstrate that both cleavage sites within the conserved 79-nt SII as well as RNA folding in this region are essential for SIDER2-mediated mRNA decay, and further support that SIDER2-harboring transcripts are targeted for degradation by endonucleolytic cleavage.
[Mh] Termos MeSH primário: Leishmania/genética
RNA Mensageiro/química
RNA de Protozoário/química
Elementos Nucleotídeos Curtos e Dispersos
[Mh] Termos MeSH secundário: Sequência de Bases
Simulação por Computador
Sequência Conservada
Modelos Moleculares
Mutagênese Sítio-Dirigida
Conformação de Ácido Nucleico
Estabilidade de RNA
Deleção de Sequência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Messenger); 0 (RNA, Protozoan)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170714
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0180678


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[PMID]:28704369
[Au] Autor:Martínez-Valencia AJ; Daza-Rivera CF; Rosales-Chilama M; Cossio A; Casadiego Rincón EJ; Desai MM; Saravia NG; Gómez MA
[Ad] Endereço:Centro Internacional de Entrenamiento e Investigaciones Médicas-CIDEIM, Cali, Colombia.
[Ti] Título:Clinical and parasitological factors in parasite persistence after treatment and clinical cure of cutaneous leishmaniasis.
[So] Source:PLoS Negl Trop Dis;11(7):e0005713, 2017 Jul.
[Is] ISSN:1935-2735
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The determinants of parasite persistence or elimination after treatment and clinical resolution of cutaneous leishmaniasis (CL) are unknown. We investigated clinical and parasitological parameters associated with the presence and viability of Leishmania after treatment and resolution of CL caused by L. Viannia. METHODS: Seventy patients who were treated with meglumine antimoniate (n = 38) or miltefosine (n = 32) and cured, were included in this study. Leishmania persistence and viability were determined by detection of kDNA and 7SLRNA transcripts, respectively, before, at the end of treatment (EoT), and 13 weeks after initiation of treatment in lesions and swabs of nasal and tonsillar mucosa. RESULTS: Sixty percent of patients (42/70) had evidence of Leishmania persistence at EoT and 30% (9/30) 13 weeks after treatment initiation. A previous episode of CL was found to be a protective factor for detectable Leishmania persistence (OR: 0.16, 95%CI: 0.03-0.92). kDNA genotyping could not discern differences between parasite populations that persisted and those isolated at diagnosis. CONCLUSIONS: Leishmania persist in skin and mucosal tissues in a high proportion of patients who achieved therapeutic cure of CL. This finding prompts assessment of the contribution of persistent infection in transmission and endemicity of CL, and in disease reactivation and protective immunity.
[Mh] Termos MeSH primário: Leishmania/isolamento & purificação
Leishmaniose Cutânea/tratamento farmacológico
Leishmaniose Cutânea/parasitologia
[Mh] Termos MeSH secundário: Adolescente
Adulto
Idoso
DNA de Cinetoplasto/análise
DNA de Protozoário/análise
Feminino
Seguimentos
Seres Humanos
Leishmania/fisiologia
Masculino
Meia-Idade
Membrana Mucosa/parasitologia
Estudos Prospectivos
RNA de Protozoário/análise
RNA Citoplasmático Pequeno/análise
Partícula de Reconhecimento de Sinal/análise
Pele/parasitologia
Análise de Sobrevida
Fatores de Tempo
Resultado do Tratamento
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (7SL RNA); 0 (DNA, Kinetoplast); 0 (DNA, Protozoan); 0 (RNA, Protozoan); 0 (RNA, Small Cytoplasmic); 0 (Signal Recognition Particle)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170714
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pntd.0005713



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