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Caractérisation moléculaire de la rétine embryonnaire et larvaire de la lamproie Petromyzon marinus / Molecular characterization in the developing eye of the lamprey Petromyzon marinusRocancourt, Claire 09 December 2010 (has links)
La lamproie présente un mode de développement de la rétine très particulier parmi les vertébrés. Elle implique deux processus distincts. Le premier conduit à la formation précoce d’une rétine centrale, qui présente des indications de différenciation dès les stades prolarvaires et ne contient que trois types cellulaires différenciés (photorécepteurs, cellules bipolaires et cellules ganglionnaires). Dans un deuxième temps, au cours des stades larvaires, une rétine périphérique, dont dérive l’essentiel de la rétine adulte, se développe à la marge de la rétine centrale. Elle croît de façon importante jusqu’à la métamorphose, au cours de laquelle la différenciation des différents types cellulaires s’effectue. J’ai engagé une analyse des programmes génétiques qui contrôlent ces processus en étudiant les profils d’expression de trois paralogues de la famille Otx (PmOtxA/B/C), ainsi que des gènes PmFoxG1, PmPax6, PmVax2 et PmSix3 au cours du développement précoce de l’oeil, aux stades prolarvaires. L’analyse de l’expression des gènes PmPax6, PmOtxB et PmOtxC a également été étudiée au cours des stades larvaires et dans la rétine différenciée post-métamorphique. Enfin des traitements pharmacologiques visant à inhiber l’activité du récepteur au FGF ont été effectués, en vue d’évaluer le rôle des signalisations médiées par ce récepteur aux stades prolarvaires. Les résultats mettent en évidence un patron de régionalisation de la cupule optique très semblable entre la lamproie et les gnathostomes. Les traitements pharmacologiques suggèrent également des mécanismes de spécification du pédoncule optique conservés à l’échelle des vertébrés. Au cours de la différenciation de la rétine centrale et de la formation de la rétine périphérique, les gènes PmPax6 et PmOtxB/C présentent également une dynamique d’expression globalement conservée, avec quelques différences. Ces analyses fournissent la première caractérisation des programmes génétiques contrôlant la formation de l’oeil chez la lamproie. A la suite de ces analyses, la formation de la rétine centrale apparaît comme un processus accessible aux caractérisations moléculaires et aux analyses fonctionnelles et d’un intérêt majeur à la fois pour des aspects évolutifs et mécanistiques. / The lamprey presents a very particular way of development of the retina among the vertebrates. It implies two distinct processes. The first lead to the early formation of a central retina, which presents indications of differentiation in prolarval stages and contains only three differentiated cellular types (bipolar cells, photoreceptors and ganglionar cells). Secondly, during larval stages, a peripheral retina, of which the main part of the adult retina derives, develops within the margin of the central retina. It grows in an important way until the metamorphosis, during which the differentiation of the various cellular types is carried out. I engaged an analysis of the genetic programs which control these processes by studying the expression profiles of three paralogues of the Otx family (PmOtxA/B/C), as well as PmFoxG1, PmPax6, PmVax2 and PmSix3 genes during the early development of the eye, at the stages prolarvaires. The expression analysis of PmPax6, PmOtxB and PmOtxC genes was also studied during larval stages and in the post-metamorphic differentiated retina. Finally pharmacological treatments aiming at inhibiting the activity of the FGF receptor were carried out, in order to evaluate the role of the indications mediated by this receptor at the prolarval stages. The results highlight a very similar regionalization pattern of the optical cup between the lamprey and the gnathostomes. The pharmacological treatments also suggest specification mechanisms of the optical stalk preserved at the level of vertebrate. During the differentiation of the central retina and formation of the peripheral retina, the PmPax6 genes and PmOtxB/C also present a conserved dynamic expression, with some differences. These analyzes provide the first characterization of the genetic programs controlling the formation of the eye in the lamprey. Following these analyzes, the formation of the central retina seems to be an accessible process to molecular characterizations and to functional analyzes and it is a major interest for both evolutionary and mechanistic aspects.
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Identification and molecular characterization of dPALS2, the Drosophila ortholog of Mammalian PALS2Teal, Kelly 05 1900 (has links)
<p> The proper organization of receptors and signal transduction protein complexes of
epithelial and neuronal cells is crucial in tissue formation, cellular differentiation and
proper overall development and function. Scaffolding proteins are major components
involved in protein targeting and protein complex assembly. MAGUK.s, a family of
scaffolding proteins with multiple binding domains such as PDZ, SH3 and GUK, are
important regulators of cellular polarity by recruiting and assembling signal and
cytoskeletal components into large complexes. Cell polarity is established and
maintained by the proper formation and placement of cellular junctions, which separate
the plasma membrane into two distinct domains: apical and basolateral. Epithelial
polarity determinants from the Bazooka, Crumbs and Scribble complexes establish the
boundaries between the apical and basolateral membrane domains and situate the
adherens junctions (AJ) at the interface between the two domains. In neuronal cells, the
organization and polarization of the presynaptic and the postsynaptic membranes is
organized by the CASKIVELIIMINTl/Xllalpha complex. Both CASK and VELI also
play a role in epithelial cells. </p> <p> Two novel proteins, originally discovered by Far Western overlay assay in Mus musculus, have been identified as additional binding partners of VELI: PALS I and PALS2. Both proteins are MAGUK.s and are thought to compete with CASK for binding
VELI via L27 domain dimerization. PALSl, a major component of the Crumbs complex,
is essential for the formation of AJ and the establishment of cellular polarity. PALS2 has
been shown to co localize with E-cadherin below tight junctions and directly associate with nectin-like molecule-2 (Necl-2) at extra junctional regions, however its function
remains unknown. </p> <p> Using Drosophila melanogaster as a model organism, we have identified the potential Drosophila ortholog of P ALS2, termed dP ALS2, and found that it is conserved
across other species. We have done extensive sequence analysis of dP ALS2 at the
nucleotide and amino acid level and determined the RNA transcript distribution and
protein localization. </p> <p> dP ALS2 expression begins around stage 13 in embryonic tissues in a transversestriped pattern in the epithelia and continues in this striped pattern until the end of stage
17. dP ALS2 is expressed in adult tissues but undetectable in larval tissues. Based on
homology and the expression pattern, dP ALS2 may play a role in cell adhesion or cell
polarity, similar to the mammalian orthologs. However the striped expression pattern of
dPALS2 is similar to segment polarity proteins thus implying dPALS2 may play a role in
segment polarity. </p> / Thesis / Master of Science (MSc)
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Molecular and Functional Characterization of the Mouse PEA3 Promoter / Characterization of the Mouse PEA3 PromoterBarrett, Jane Marie 07 1900 (has links)
PEA3 is a member of the expanding Ets family of transcription factors. In the adult mouse, PEA3 mRNA is expressed at highest levels in the brain, epididymis and at lower levels in the mammary gland, testes, ovary and uterus. PEA3 mRNA is expressed differentially during mouse embryogenesis and is down-regulated following retinoic acid induced differentiation in mouse embryonal carcinoma cell lines. PEA3 is overexpressed at the transcriptional level in 93% of all HER2/neu positive human breast tumors. The molecular basis for differential transcription of the PEA3 gene is not known. Sequence analysis revealed that the upstream region of the PEA3 gene has characteristics of a CpG island and does not possess a recognizable "TATA" element. Rapid amplification of 5' eDNA ends (5'RACE) reveals that transcription initiates from multiple sites, consistent with the absence of TATA elements. To localize cis-acting sequences required for PEA3 expression, deletions of the putative promoter were placed upstream of a luciferase reporter gene and tested for activity in the FM3A cell line. FM3A cells express substantial levels of PEA3 mRNA and protein, which suggests that all of the factors required for transcription are present in the cells. Transient transfections of 5' and 3' deletion mutants of the PEA3 promoter indicated that the efficiency of the PEA3 promoter depended on both negative and positive cis-elements, located upstream and downstream of the transcription start sites. A DNA fragment containing a region from -3 to +676, relative to the major start site of transcription, was sufficient for maximal promoter activity.
Luciferase reporter plasmids containing more 5' flanking sequence had lower activity indicating the presence of silencer elements. To aid the identification of critical sequence elements within the minimal PEA3 promoter, we cloned and sequenced the putative human PEA3 promoter. Comparison of the mouse and human PEA3 DNAs revealed that sequences required for maximal promoter activity in the mouse were highly conserved in the human gene. Furthermore, these conserved sequences corresponded to a variety of consensus binding sites: 6 Sp1, 8 c-ets-1, 3 PEA3, 3 AP-2, 3 MZF-1, 2 MyoD, 2 Ik-1, 2 c/EBPB, 2 oEF-1/USF, 2 HSFI and one of each of the following: AP-4, Ik-2, SRY, CP2, HEN-I, CREB andE47. / Thesis / Master of Science (MS)
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Molecular characterization on a t(1;1)(p13;p36) acute megakaryoblastic leukemia (AMKL)Hsieh, Ya-lan 27 October 2004 (has links)
Acute megakaryoblastic leukemia (AMKL) was first described by Von Boros and Karangi in 1931, was a result of developments in ultrastructural cytochemistry and immunologic phenotyping acute myeloid leukemia (AML) of megakaryocytic lineage have been diagnosed increasingly. The French-American-British (FAB) Co-operative Group established the criteria for the diagnosis and added this category as a distinct subtype of AML (M7) in 1985. The main subtypes of AML in the infants are M4, M5, and M7. One 25-day-old infant was referred to the hospital for further examination of white blood cell. Hepatosplenomegaly and anemia were physically examined, and he was diagnosed to be an AMKL case. Abnormal karyotype 46,XY,t(1;1)(p13;p36) was observed in this patient. This study aims to identify the AMKL potentially related genes on the breakpoints of Homo sapiens autosomal (HSA) 1p13 and 1p36 in this case by candidate gene approaches. Data-mining of the AMKL potentially related genes on breakpoints of HSA1p13 and 1p36 through NCBI Map Viewer Database, OMIM Morbid Map, and OMIM Gene Map were performed. We identified three candidate genes on HSA1p13 and 15 candidate genes on HSA 1p36. RBM15-MKL1 fusion on t(1;22)(p13;q13) was reported to be AMKL genes by Ma et al., Mercher et al., and the Mitelman Database of Chromosome Aberrations in Cancer. We anticipated RBM15 is also a related gene on HSA1p13 in this AMKL case, and compared the Gene Ontology terms between MKL1 and these 15 candidate genes on HSA1p36. SKI becomes our first candidate gene on 1p36 in this case. To identify candidate genes locating at HSA1p13 and 1p36, including RBM15 and SKI were screened at both cDNA and genomic DNA levels. According to these results, RBM15 and SKI are more likely to be candidate genes. Thus RBM15 and SKI may be the novel AMKL genes in t(1;1)(p13;p36) AMKL patients.
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Sorodiagnóstico, isolamento e genotipagem de Toxoplasma gondii e investigação molecular de outros protozoários pertencentes à família Sarcocystidae em morcegos do estado de São Paulo / Serodiagnosis, isolation and genotyping of Toxoplasma gondii and molecular investigation of other protozoa belonging to the Sarcocystidae family in bats from São Paulo stateCabral, Aline Diniz 18 March 2013 (has links)
Os trabalhos existentes sobre protozoários pertencentes à família Sarcocystidae em morcegos são escassos e desatualizados. No Brasil, a ocorrência de Toxoplasma gondii é bem documentada nas espécies domésticas e no Homem, existindo relatos em diversos hospedeiros selvagens. Mundialmente, existe um grande interesse no conhecimento da variedade genética de T. gondii realizada por meio da Reação em Cadeia pela Polimerase Polimorfismo de Comprimento de Fragmentos de DNA gerados por Enzimas de Restrição (PCR-RFLP). No presente trabalho, objetivou-se pesquisar a frequência de ocorrência de anticorpos anti-T. gondii, isolar e caracterizar molecularmente T. gondii e investigar a presença de coccídios da família Sarcocystidae em morcegos de vida livre no estado de São Paulo. Um total de 1921 morcegos, provenientes de 15 municípios do estado de São Paulo, foi examinado durante o período de março de 2010 a março de 2011. Obteve-se 14,89% (28/188) de positividade para T. gondii na Reação de Imunofluorescência Indireta (RIFI ≥ 16) e 18,61% (35/188) no Teste de Aglutinação Modificado (MAT ≥ 25), com baixa concordância entre as técnicas utilizando o índice Kappa (K=0,046). De um total de 282 bioensaios em camundongos, foram obtidos dois isolados, sendo TgBatBr1 proveniente de Molossus molossus, insetívoro, macho e adulto, e TgBatBr2 proveniente de Desmodus rotundus, hematófago, macho e adulto, ambos causando 100% de mortalidade em camundongos. A genotipagem dos isolados e das amostras primárias de morcegos positivas para T. gondii foi feita por meio da PCR-RFLP com os marcadores SAG1, 5\'3\'SAG2, SAG3, BTUB, GRA6, alt. SAG2, c22-8, c29-2, PK1, Apico, L358 e CS3, revelando os genótipos ToxoDB-RFLP #162 e #19, respectivamente, para os isolados TgBatBr1 e TgBatBr2. Para a investigação molecular dos sarcocistídeos foram utilizados primers que amplificam a região 18S do DNA ribossomal e as amostras positivas foram sequenciadas. A análise de sequências pôde ser realizada em 48 das amostras positivas para Sarcocystidae, encontrando-se 100% de identidade com T. gondii em quatro morcegos e também 100% de identidade com Neospora caninum, Hammondia hammondi, Cystoisospora ohioensis e Frenkelia glareoli em um morcego, respectivamente. Outras 39 amostras apresentaram identidade de 94-98% com outros sarcocistídeos e, provavelmente, devem ser novas espécies. Foi possível a genotipagem de amostras primárias positivas para T. gondii de um morcego insetívoro (Eumops glaucinus), correspondendo ao genótipo #69 e de outro morcego insetívoro (E. glaucinus), apresentando o genótipo #6, que corresponde ao Tipo BrI. Há uma necessidade de se investigar a importância dos morcegos como reservatórios de doenças infecciosas, podendo-se sugerir a inclusão do diagnóstico de T. gondii como diferencial para raiva. Ressalta-se também a importância do compartilhamento dos genótipos de T. gondii dos morcegos com hospedeiros terrestres e dos estudos sobre sarcocistídeos em morcegos, a fim de compreender melhor as relações parasita-hospedeiro. / The existing studies on protozoa belonging to the Sarcocystidae family are scarce and outdated in free-living bats. In Brazil, the occurrence of Toxoplasma gondii is well documented in domestic animals and humans, with reports in several wild hosts. Worldwide, there is a great interest in understanding the genetic variation of T. gondii using differen molecular tools as the Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP). The present study aimed to research the frequency of occurrence of anti-T. gondii antibodies, to isolate and molecularly characterize T. gondii and to investigate the presence of coccidia from Sarcocystidae family in free-living bats from São Paulo state. A total of 1921 bats from 15 municipalities in São Paulo state were examined from March 2010 to March 2011. It was obtained 14.89% (28/188) of positivity for T. gondii by Indirect Immunofluorescence Assay (IFA ≥ 16) and 18.61% (35/188) by Modified Agglutination Test (MAT ≥ 25) with low agreement between techniques when using Kappa (K = 0.046). From a total of 282 bioassays in mice, two bat isolates were obtained, TgBatBr1 from Molossus molossus, an insectivorous, male, adult bat, and TgBatBr2 from Desmodus rotundus, a vampire, male, adult bat, both causing 100% of mouse mortality. Genotyping of isolates and T. gondii positive primary samples from bats were performed by PCR-RFLP using markers SAG1, 5\'3\'SAG2, SAG3, BTUB, GRA6, alt. SAG2, c22-8, c29-2, PK1, Apico, L358 and CS3, revealing ToxoDB-RFLP genotypes #162 and #19, respectively, for isolates TgBatBr1 and TgBatBr2. Primers that amplify the 18S ribosomal DNA region were employed for molecular investigation of Sarcocystidae in primary samples and the positive samples were sequenced. Analysis of sequence could be accomplished for 48 Sarcocystidae positive samples. A 100% identity with T. gondii was found in four bats, and with Neospora caninum, Hammondia hammondi, Cystoisospora ohioensis and Frenkelia glareoli in a bat, respectively. Thirty-nine samples showed 94-98% identity with other Sarcocystidae and, probably, these are new species. Genotyping of positive primary samples for T. gondii was complete from one insectivorous bat (Eumops glaucinus), corresponding to genotype # 69 and from other insectivorous bat (E. glaucinus), showing genotype # 6, which corresponds to the Type BrI. It is necessary to investigate the importance of bats as reservoirs of infectious diseases, and it could be suggested the inclusion of the diagnosis of T. gondii as a differential to rabies. We also emphasize the importance of T. gondii genotypes from bats being shared with terrestrial hosts and of studies on Sarcocystidae in bats in order to better understand the host-parasite relationship.
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Characterization of systemic acquired resistance in <i>Brassica napus</i>Potlakayala, Shobha Devi 13 November 2006
Plants activate an array of defense mechanisms upon pathogen attack. Systemic acquired resistance (SAR) is an induced disease resistance phenomenon deployed after infection by a necrogenic pathogen and is dependent on endogenous accumulation of salicylic acid. The objectives of my research were to characterize SAR in the crop plant, <i>Brassica napus</i> (canola), and study the effects of overexpressing genes involved in SAR on disease resistance. Biological induction of SAR using necrogenic Pseudomonas syringae and chemical induction using benzo (1,2,3) thiadiazole-7-carbothionic acid reduced growth of the bacterial pathogen P. syringae and the fungal pathogen Leptosphaeria maculans. This growth reduction was associated with an increase in transcript levels of pathogenesis-related (PR) genes, one of the characteristic features of SAR. Transgenic plants expressing a bacterial salicylate hydroxylase gene (NahG), were more susceptible to the above pathogens and were delayed in accumulating PR gene transcripts, indicating a need for SA accumulation for SAR in B. napus. Expression of two SAR genes from Arabidopsis, DEFECTIVE IN INDUCED RESISTANCE 1 (DIR1) and NON EXPRESSOR OF PATHOGENESIS-RELATED 1 (NPR1), in <i>B. napus</i> enhanced resistance against virulent P. syringae without SAR pre-treatments. Putative orthologs of DIR1 and NPR1 (BnDIR1 and BnNPR1) were isolated from B. napus based on EST sequences. BnDIR1 and BnNPR1 display 71% and 66% amino acid sequence similarities, respectively, to the corresponding Arabidopsis proteins. Expression of BnNPR1 in Arabidopsis npr1 mutant backgrounds indicated that it was able to functionally complement these mutations. Expression of BnDIR1 enhanced disease resistance in both Arabidopsis wild-type and dir1-1 mutant backgrounds. Expression of DIR1, NPR1, BnDIR1 and BnNPR1, separately, in <i>B. napus</i> plants enhanced resistance against P. syringae. SAR pre-treatments further enhanced resistance of transgenic <i>B. napus</i> plants expressing DIR1 and BnDIR1 to <i>P. syringae</i>, indicating an additive effect. Expression of DIR1 in B. napus did not provide resistance against <i>L. maculans</i>. These results provide the first in-depth molecular characterization of SAR in B. napus, and in particular, provide new insight into DIR1 function not previously reported in Arabidopsis.
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Characterization of systemic acquired resistance in <i>Brassica napus</i>Potlakayala, Shobha Devi 13 November 2006 (has links)
Plants activate an array of defense mechanisms upon pathogen attack. Systemic acquired resistance (SAR) is an induced disease resistance phenomenon deployed after infection by a necrogenic pathogen and is dependent on endogenous accumulation of salicylic acid. The objectives of my research were to characterize SAR in the crop plant, <i>Brassica napus</i> (canola), and study the effects of overexpressing genes involved in SAR on disease resistance. Biological induction of SAR using necrogenic Pseudomonas syringae and chemical induction using benzo (1,2,3) thiadiazole-7-carbothionic acid reduced growth of the bacterial pathogen P. syringae and the fungal pathogen Leptosphaeria maculans. This growth reduction was associated with an increase in transcript levels of pathogenesis-related (PR) genes, one of the characteristic features of SAR. Transgenic plants expressing a bacterial salicylate hydroxylase gene (NahG), were more susceptible to the above pathogens and were delayed in accumulating PR gene transcripts, indicating a need for SA accumulation for SAR in B. napus. Expression of two SAR genes from Arabidopsis, DEFECTIVE IN INDUCED RESISTANCE 1 (DIR1) and NON EXPRESSOR OF PATHOGENESIS-RELATED 1 (NPR1), in <i>B. napus</i> enhanced resistance against virulent P. syringae without SAR pre-treatments. Putative orthologs of DIR1 and NPR1 (BnDIR1 and BnNPR1) were isolated from B. napus based on EST sequences. BnDIR1 and BnNPR1 display 71% and 66% amino acid sequence similarities, respectively, to the corresponding Arabidopsis proteins. Expression of BnNPR1 in Arabidopsis npr1 mutant backgrounds indicated that it was able to functionally complement these mutations. Expression of BnDIR1 enhanced disease resistance in both Arabidopsis wild-type and dir1-1 mutant backgrounds. Expression of DIR1, NPR1, BnDIR1 and BnNPR1, separately, in <i>B. napus</i> plants enhanced resistance against P. syringae. SAR pre-treatments further enhanced resistance of transgenic <i>B. napus</i> plants expressing DIR1 and BnDIR1 to <i>P. syringae</i>, indicating an additive effect. Expression of DIR1 in B. napus did not provide resistance against <i>L. maculans</i>. These results provide the first in-depth molecular characterization of SAR in B. napus, and in particular, provide new insight into DIR1 function not previously reported in Arabidopsis.
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Molecular Characterization of pFGE, the Paralog of the C-α-Formylglycine-generating Enzyme / Molecular Characterization of pFGE, the Paralog of the C-α-Formylglycine-generating EnzymeMariappan, Malaiyalam 01 November 2005 (has links)
No description available.
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Sorodiagnóstico, isolamento e genotipagem de Toxoplasma gondii e investigação molecular de outros protozoários pertencentes à família Sarcocystidae em morcegos do estado de São Paulo / Serodiagnosis, isolation and genotyping of Toxoplasma gondii and molecular investigation of other protozoa belonging to the Sarcocystidae family in bats from São Paulo stateAline Diniz Cabral 18 March 2013 (has links)
Os trabalhos existentes sobre protozoários pertencentes à família Sarcocystidae em morcegos são escassos e desatualizados. No Brasil, a ocorrência de Toxoplasma gondii é bem documentada nas espécies domésticas e no Homem, existindo relatos em diversos hospedeiros selvagens. Mundialmente, existe um grande interesse no conhecimento da variedade genética de T. gondii realizada por meio da Reação em Cadeia pela Polimerase Polimorfismo de Comprimento de Fragmentos de DNA gerados por Enzimas de Restrição (PCR-RFLP). No presente trabalho, objetivou-se pesquisar a frequência de ocorrência de anticorpos anti-T. gondii, isolar e caracterizar molecularmente T. gondii e investigar a presença de coccídios da família Sarcocystidae em morcegos de vida livre no estado de São Paulo. Um total de 1921 morcegos, provenientes de 15 municípios do estado de São Paulo, foi examinado durante o período de março de 2010 a março de 2011. Obteve-se 14,89% (28/188) de positividade para T. gondii na Reação de Imunofluorescência Indireta (RIFI ≥ 16) e 18,61% (35/188) no Teste de Aglutinação Modificado (MAT ≥ 25), com baixa concordância entre as técnicas utilizando o índice Kappa (K=0,046). De um total de 282 bioensaios em camundongos, foram obtidos dois isolados, sendo TgBatBr1 proveniente de Molossus molossus, insetívoro, macho e adulto, e TgBatBr2 proveniente de Desmodus rotundus, hematófago, macho e adulto, ambos causando 100% de mortalidade em camundongos. A genotipagem dos isolados e das amostras primárias de morcegos positivas para T. gondii foi feita por meio da PCR-RFLP com os marcadores SAG1, 5\'3\'SAG2, SAG3, BTUB, GRA6, alt. SAG2, c22-8, c29-2, PK1, Apico, L358 e CS3, revelando os genótipos ToxoDB-RFLP #162 e #19, respectivamente, para os isolados TgBatBr1 e TgBatBr2. Para a investigação molecular dos sarcocistídeos foram utilizados primers que amplificam a região 18S do DNA ribossomal e as amostras positivas foram sequenciadas. A análise de sequências pôde ser realizada em 48 das amostras positivas para Sarcocystidae, encontrando-se 100% de identidade com T. gondii em quatro morcegos e também 100% de identidade com Neospora caninum, Hammondia hammondi, Cystoisospora ohioensis e Frenkelia glareoli em um morcego, respectivamente. Outras 39 amostras apresentaram identidade de 94-98% com outros sarcocistídeos e, provavelmente, devem ser novas espécies. Foi possível a genotipagem de amostras primárias positivas para T. gondii de um morcego insetívoro (Eumops glaucinus), correspondendo ao genótipo #69 e de outro morcego insetívoro (E. glaucinus), apresentando o genótipo #6, que corresponde ao Tipo BrI. Há uma necessidade de se investigar a importância dos morcegos como reservatórios de doenças infecciosas, podendo-se sugerir a inclusão do diagnóstico de T. gondii como diferencial para raiva. Ressalta-se também a importância do compartilhamento dos genótipos de T. gondii dos morcegos com hospedeiros terrestres e dos estudos sobre sarcocistídeos em morcegos, a fim de compreender melhor as relações parasita-hospedeiro. / The existing studies on protozoa belonging to the Sarcocystidae family are scarce and outdated in free-living bats. In Brazil, the occurrence of Toxoplasma gondii is well documented in domestic animals and humans, with reports in several wild hosts. Worldwide, there is a great interest in understanding the genetic variation of T. gondii using differen molecular tools as the Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP). The present study aimed to research the frequency of occurrence of anti-T. gondii antibodies, to isolate and molecularly characterize T. gondii and to investigate the presence of coccidia from Sarcocystidae family in free-living bats from São Paulo state. A total of 1921 bats from 15 municipalities in São Paulo state were examined from March 2010 to March 2011. It was obtained 14.89% (28/188) of positivity for T. gondii by Indirect Immunofluorescence Assay (IFA ≥ 16) and 18.61% (35/188) by Modified Agglutination Test (MAT ≥ 25) with low agreement between techniques when using Kappa (K = 0.046). From a total of 282 bioassays in mice, two bat isolates were obtained, TgBatBr1 from Molossus molossus, an insectivorous, male, adult bat, and TgBatBr2 from Desmodus rotundus, a vampire, male, adult bat, both causing 100% of mouse mortality. Genotyping of isolates and T. gondii positive primary samples from bats were performed by PCR-RFLP using markers SAG1, 5\'3\'SAG2, SAG3, BTUB, GRA6, alt. SAG2, c22-8, c29-2, PK1, Apico, L358 and CS3, revealing ToxoDB-RFLP genotypes #162 and #19, respectively, for isolates TgBatBr1 and TgBatBr2. Primers that amplify the 18S ribosomal DNA region were employed for molecular investigation of Sarcocystidae in primary samples and the positive samples were sequenced. Analysis of sequence could be accomplished for 48 Sarcocystidae positive samples. A 100% identity with T. gondii was found in four bats, and with Neospora caninum, Hammondia hammondi, Cystoisospora ohioensis and Frenkelia glareoli in a bat, respectively. Thirty-nine samples showed 94-98% identity with other Sarcocystidae and, probably, these are new species. Genotyping of positive primary samples for T. gondii was complete from one insectivorous bat (Eumops glaucinus), corresponding to genotype # 69 and from other insectivorous bat (E. glaucinus), showing genotype # 6, which corresponds to the Type BrI. It is necessary to investigate the importance of bats as reservoirs of infectious diseases, and it could be suggested the inclusion of the diagnosis of T. gondii as a differential to rabies. We also emphasize the importance of T. gondii genotypes from bats being shared with terrestrial hosts and of studies on Sarcocystidae in bats in order to better understand the host-parasite relationship.
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Molecular Characterization of Root-Lesion Nematode Species from Corn Fields in North Dakota and Evaluation of Resistance in Corn HybridsAkhter, Nasima January 2019 (has links)
The molecular characterization of Pratylenchus species determined from D2-D3 of 28S rDNA, ITS of rDNA, and COI of mtDNA regions revealed four Pratylenchus species from North Dakota, P. scribneri, P. neglectus, Pratylenchus sp. (ND-2016 isolate HG51), and Pratylenchus sp. (ND-2017). They were clustered in four separate clades in the phylogenetic trees indicating the divergence among species. P. scribneri and Pratylenchus sp. (ND-2016 isolate HG51) were closely associated and Pratylenchus sp. (DH-2017) was closely related to Pratylenchus sp. (ND-2016 isolate HG51). However, P. neglectus was not closely associated with the other three species. Moreover, resistance evaluation of ten corn hybrids to Pratylenchus scribneri, P. neglectus, and Pratylenchus sp. (ND-2017) revealed that 1392 VT2P was moderately resistant to three Pratylenchus species. PFS74K89 and 4913 VT2RIB were moderately resistant to two of the three Pratylenchus species. X5B-8801, DK 43-46, and DKC 44-13 were susceptible to two of the three Pratylenchus species.
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