scholarly journals Molecular Characterization of a Reemergent Brugia malayi Parasite in Sri Lanka, Suggestive of a Novel Strain

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
C. H. Mallawarachchi ◽  
T. G. A. N. Chandrasena ◽  
G. P. Withanage ◽  
R. Premarathna ◽  
S. M. N. S. M. Mallawarachchi ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Brugia Malayi ◽  
Public Health Issue ◽  
Hybrid Strain ◽  
Species Identity ◽  
Internal Transcribed Spacer Region ◽  
Pairwise Divergence ◽  
The Mean ◽  
Polymerase Chain

Sri Lanka achieved elimination status for lymphatic filariasis in 2016; still, the disease remains a potential public health issue. The present study is aimed at identifying a subperiodic Brugia sp. parasite which has reemerged in Sri Lanka after four decades via molecular-based analysis. Polymerase chain reaction performed with pan-filarial primers specific for the internal transcribed spacer region-2 (ITS-2) of the rDNA of Brugia filarial parasites isolated from human, canine, and feline blood samples yielded a 615 bp band establishing the species identity as Brugia malayi. Comparison of the ITS2 sequences of the reemerged B. malayi isolates with GenBank sequences revealed a higher sequence homology with B. pahangi than B. malayi with similar phylogenetic evidence. However, the mean interspecies Kimura-2-parameter pairwise divergence between the generated Brugia sequences with B. malayi and B. pahangi was less than 3%. During the analysis of parsimony sites of the new ITS2 sequences, substitutions at A36T, A296G, T373A, and G482A made the sequences different from both B. pahangi and B. malayi suggesting the possibility of a new genetic variant or a hybrid strain of B. malayi and B. pahangi. Mosquito dissections and xenomonitoring identified M. uniformis and M. annulifera as vectors of this novel strain of B. malayi circulating among cats, dogs, and humans in Sri Lanka.

scholarly journals Molecular Characterization of a Re-Emergent Brugia Malayi Parasite in Sri Lanka, Suggestive of a Novel Strain With Close Nucleotide Homology to Brugia Pahangi

2020 ◽  
Author(s):  
Chandana Harendra Mallawarachchi ◽  
Nilmini T. G. A. N Chandrasena ◽  
Ranjan Premarathna ◽  
S.M.N.S.M. Maleesha Mallawarachchi ◽  
Nilmini Y. I. S. Gunawardane ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Its2 Region ◽  
Species Identity ◽  
Internal Transcribed Spacer Region ◽  
Region Gene ◽  
Specific Pcr ◽  
Baited Traps ◽  
Human Blood Samples ◽  
Polymerase Chain

Abstract Background Brugian filariasis has re-emerged in Sri Lanka after four decades of quiescence. As microscopy alone was insufficient for ascertaining the species identity of the re-emerged sub-periodic Brugia spp. parasite, molecular speciation was performed. The transmission dynamics of the parasite was studied by entomological procedures.Methods Human blood samples positive for Brugia spp. microfilariae (MF) (n=8) were collected and DNA extracted using ReliaPrep™ Blood DNA Miniprep System (modified). Polymerase chain reaction (PCR) was performed with pan-filarial primers specific for the internal transcribed spacer region 2 (ITS2) of the ribosomal DNA (rDNA) of MF. Results Of those tested, seven (87.5%) yielded a band at 615bp establishing the species identity of the re-emerged filarial parasite as B. malayi. Comparison of the ITS2 region gene sequences of B. malayi MF isolated from humans (n=2), dogs (n=3) and cats (n=6) with GenBank sequences revealed a higher sequence homology with B. pahangi than B. malayi, but phylogeny was closer to B. malayi. A total of 82 mosquitoes of genus Mansonia comprising of M. annulifera (65), M. uniformis (14) and M. indiana (3) were collected by cattle-baited traps. Mosquito dissections identified 17 infected mosquitoes: one M. uniformis (7.14%) and 16 M. annulifera (24.6%). The DNA extracts of all infected Mansonia mosquitoes elicited the 615bp band on pan-filarial primer specific PCR. Conclusions The re-emergent B. malayi is a genetic variant or a novel species closely related to B. malayi and B. pahangi. Mansonia spp. mosquitoes were vectors of this zoonotic variant B. malayi circulating among cats, dogs and humans in Sri Lanka.

scholarly journals Molecular characterization of a re-emergent Brugia malayi parasite in Sri Lanka, suggestive of a novel strain with close nucleotide homology to Brugia pahangi

2020 ◽  
Author(s):  
Chandana Harendra Mallawarachchi ◽  
Nilmini T. G. A. N Chandrasena ◽  
Ranjan Premarathna ◽  
S.M.N.S.M. Maleesha Mallawarachchi ◽  
Nilmini Y. I. S. Gunawardane ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Its2 Region ◽  
Species Identity ◽  
Internal Transcribed Spacer Region ◽  
Region Gene ◽  
Specific Pcr ◽  
Baited Traps ◽  
Human Blood Samples ◽  
Polymerase Chain

Abstract Background Brugian filariasis has re-emerged in Sri Lanka after four decades of quiescence. As microscopy alone was insufficient for ascertaining the species identity of the re-emerged sub-periodic Brugia spp. parasite, molecular speciation was performed. The transmission dynamics of the parasite was studied by entomological procedures.Methods Human blood samples positive for Brugia spp. microfilariae (MF) (n=8) were collected and DNA extracted using ReliaPrep™ Blood DNA Miniprep System (modified). Polymerase chain reaction (PCR) was performed with pan-filarial primers specific for the internal transcribed spacer region 2 (ITS2) of the ribosomal DNA (rDNA) of MF. Results Of those tested, seven (87.5%) yielded a band at 615bp establishing the species identity of the re-emerged filarial parasite as B. malayi. Comparison of the ITS2 region gene sequences of B. malayi MF isolated from humans (n=2), dogs (n=3) and cats (n=6) with GenBank sequences revealed a higher sequence homology with B. pahangi than B. malayi, but phylogeny was closer to B. malayi. A total of 82 mosquitoes of genus Mansonia comprising of M. annulifera (65), M. uniformis (14) and M. indiana (3) were collected by cattle-baited traps. Mosquito dissections identified 17 infected mosquitoes: one M. uniformis (7.14%) and 16 M. annulifera (24.6%). The DNA extracts of all infected Mansonia mosquitoes elicited the 615bp band on pan-filarial primer specific PCR. Conclusions The re-emergent B. malayi is a genetic variant or a novel species closely related to B. malayi and B. pahangi. Mansonia spp. mosquitoes were vectors of this zoonotic variant B. malayi circulating among cats, dogs and humans in Sri Lanka.

scholarly journals Characterization of Verticillium dahliae and V. tricorpus Isolates from Lettuce and Artichoke

Plant Disease ◽  
2008 ◽  
Vol 92 (1) ◽  
pp. 69-77 ◽  
Author(s):  
Qing-Ming Qin ◽  
Gary E. Vallad ◽  
Krishna V. Subbarao
Keyword(s):  
Sequence Information ◽  
Root Weight ◽  
Internal Transcribed Spacer Region ◽  
Early Introduction ◽  
Reduced Height ◽  
Verticillium Tricorpus ◽  
Pathogenicity Tests ◽  
Plausible Mechanism ◽  
Polymerase Chain

Verticillium isolates collected from lettuce and artichoke were characterized for morphology, growth and pathogenicity. Several isolates were identified as Verticillium tricorpus based on morphological and cultural characteristics, including the production of dark resting mycelia, chlamydospores, microsclerotia, and yellow to orange pigmentation in culture. Compared with isolates of V. dahliae, these isolates also produced microsclerotia and conidia that were significantly larger and exhibited a distinct growth pattern at varying temperatures. Using database sequence information, primers were developed from the internal transcribed spacer region to produce a diagnostic 337-bp product specific to V. tricorpus and used to confirm the identification of isolates. Pathogenicity tests indicated that isolates of V. tricorpus were weak pathogens, causing a median disease severity (DS) of <1 (0-to-5 scale) on lettuce and artichoke. In contrast, isolates of V. dahliae consistently caused severe wilt with a median DS of >3.5 on lettuce and 5.0 on artichoke. Although lettuce and artichoke inoculated with isolates of V. tricorpus exhibited reduced height and fresh foliar and root weight, the reductions were not statistically significant, unlike in plants inoculated with isolates of V. dahliae. Lettuce co-inoculated with isolates of V. tricorpus and V. dahliae exhibited reduced symptoms of Verticillium wilt and improved growth relative to those inoculated with V. dahliae alone. The early introduction of V. tricorpus in soil-drench inoculations appeared to provide better relief from subsequent V. dahliae inoculation than when the two species were co-inoculated simultaneously using the root-dip method, suggesting competitive exclusion as a plausible mechanism. A spore-polymerase chain reaction assay developed using cultured spores directly as template and primers specific to V. tricorpus confirmed the presence of V. tricorpus on inoculated roots. This work demonstrates the potential use of V. tricorpus to directly reduce the effect of V. dahliae on lettuce and artichoke and, to our knowledge, is the first reported characterization of V. tricorpus isolates collected from lettuce and artichoke.

scholarly journals Characterization of the Colletotrichum Species Causing Anthracnose in Andean Blackberry in Colombia

Plant Disease ◽  
2014 ◽  
Vol 98 (11) ◽  
pp. 1503-1513 ◽  
Author(s):  
Lucía Afanador-Kafuri ◽  
Alonso González ◽  
Lederson Gañán ◽  
Juan Fernando Mejía ◽  
Nadya Cardona ◽  
...  
Keyword(s):  
Colletotrichum Gloeosporioides ◽  
Morphological Characteristics ◽  
High Sensitivity ◽  
Chain Reaction ◽  
Internal Transcribed Spacer Region ◽  
Colletotrichum Spp ◽  
Polymerase Chain ◽  
Polymerase Chain Reaction Primers ◽  
Multilocus Phylogeny

Since 1992, anthracnose of Andean blackberry (Rubus glaucus) has generated losses as high as 40% for farmers in Colombia. In this study, our goal was to characterize 240 Colletotrichum isolates from Andean blackberry in eight areas of Colombia. These isolates were evaluated according to morphological characteristics, sensitivity to benomyl, pathogenicity, and genetic variability. Identification of the genus Colletotrichum was achieved by using species complex-specific polymerase chain reaction primers. A multilocus phylogeny approach was used to identify isolates to the species level with sequences from the ribosomal internal transcribed spacer region and partial sequences of the actin, β-tubulin 2, calmodulin, chitin synthase 1, glutamine synthetase, and glyceraldehyde-3-phosphate dehydrogenase genes. Most of the isolates were identified as Colletotrichum gloeosporioides sensu lato, were associated with the Castilla ecotype, showed high sensitivity to benomyl, and were highly aggressive. Isolates identified as C. acutatum sensu lato were found mainly on the Thornless ecotype, were highly resistant to benomyl, and showed intermediate aggressiveness. Only three isolates were identified as C. boninense sensu lato. The species identified included C. fructicola, C. kahawae subsp. ciggaro, C. godetiae, C. karstii, C. brassicicola, and undetermined Colletotrichum spp. This study is the first report of these species associated with anthracnose in Andean blackberry.

Morphological Characterization of Rhinacanthus Species of Sri Lanka

Planta Medica ◽  
2010 ◽  
Vol 76 (05) ◽  
Author(s):  
APPR Amarasinghe ◽  
RP Karunagoda ◽  
DSA Wijesundara
Keyword(s):  
Sri Lanka ◽  
Morphological Characterization

Characterization of a cDNA for Rhesus Monkey Protein C Inhibitor – Evidence for N-Terminal Involvement in Heparin Stimulation

1995 ◽  
Vol 74 (04) ◽  
pp. 1079-1087 ◽  
Author(s):  
Klaus-P Radtke ◽  
José A Fernández ◽  
Bruno O Villoutreix ◽  
Judith S Greengard ◽  
John H Griffin
Keyword(s):  
Rhesus Monkey ◽  
Protein C ◽  
Activated Protein C ◽  
Pcr Amplification ◽  
Amino Acid Sequences ◽  
Heparin Binding ◽  
Reactive Center ◽  
Protein C Inhibitor ◽  
Polymerase Chain

SummarycDNAs for protein C inhibitor (PCI) were cloned from human and rhesus monkey 1 liver RNAs by reverse transcription and polymerase chain reaction (PCR) amplification. Sequencing showed that rhesus monkey and human PCI cDNAs were 93% identical. Predicted amino acid sequences differed at 26 of 387 residues. Pour of these differences (T352M, N359S, R362K, L3631) were in the reactive center loop that is important for inhibitory specificity, and two were in the N-terminal helix (M8T, E13K) that is implicated in glycosaminoglycan binding. PCI in human or rhesus monkey plasma showed comparable inhibitory activity towards human activated protein C in the presence of 10 U/ml heparin. However, maximal acceleration of the inhibition of activated protein C required 5-fold lower heparin concentration for rhesus monkey than for human plasma, consistent with the interpretation that the additional positive charge (E13K) in a putative-heparin binding region increased the affinity for heparin.

Characterization of the Original Christmas Disease Mutation (Cysteine 206 → Serine): From Clinical Recognition to Molecular Pathogenesis

1992 ◽  
Vol 67 (01) ◽  
pp. 063-065 ◽  
Author(s):  
Sherryl A M Taylor ◽  
Jacalyn Duffin ◽  
Cherie Cameron ◽  
Jerome Teitel ◽  
Bernadette Garvey ◽  
...  
Keyword(s):  
Nucleotide Substitution ◽  
Novel Mutation ◽  
Factor Ix ◽  
Causative Mutation ◽  
Coding Region ◽  
Body Of Knowledge ◽  
Polymerase Chain ◽  
Splice Junctions

SummaryChristmas disease was first reported as a distinct clinical entity in two manuscripts published in 1952 (1, 2). The eponym associated with this disorder, is the surname of the first patient examined in detail and reported by Biggs and colleagues in a paper describing the clinical and laboratory features of seven affected individuals (3). This patient has severe factor IX coagulant deficiency (less than 0.01 units/ml) and no detectable circulating factor IX antigen (less than 0.01 units/ml). Coding sequence and splice junctions of the factor IX gene from this patient have been amplified in vitro through the polymerase chain reaction (PCR). One nucleotide substitution was identified at nucleotide 30,070 where a guanine was replaced by a cytosine. This mutation alters the amino acid encoded at position 206 in the factor IX protein from cysteine to serine. The non conservative nature of this substitution, the absence of this change in more than 200 previously sequenced factor IX genes and the fact that the remainder of the coding region of this gene was normal, all provide strong circumstantial evidence in favour of this change being the causative mutation in this patient. The molecular characterization of this novel mutation in the index case of Christmas disease, contributes to the rapidly expanding body of knowledge pertaining to Christmas disease pathogenesis.

Caracterização da Peneira Média em Clones de Coffea canephora

REVISTA FIMCA ◽  
2018 ◽  
Vol 5 (2) ◽  
pp. 28-31
Author(s):  
Darlan Darlan Sanches Barbosa Alves ◽  
Victor Mouzinho Spinelli ◽  
Marcos Santana Moraes ◽  
Carolina Augusto De Souza ◽  
Rodrigo da Silva Ribeiro ◽  
...  
Keyword(s):  
Genetic Improvement ◽  
Block Design ◽  
Coffea Canephora ◽  
Coffee Production ◽  
Randomized Block Design ◽  
Significant Difference ◽  
The Mean ◽  
Four Blocks ◽  
Selection Of

Introdução: O estado de Rondônia se destaca como tradicional produtor de café, sendo o segundo maior produtor brasileiro de C. canephora. No melhoramento genético de C. canephora, a seleção de plantas de elevada peneira média está associada à bebida de qualidade superior. Objetivos: O objetivo desse estudo foi avaliar a variabilidade genética de clones de C. canephora para o tamanho dos grãos, mensurado a partir da avaliação da peneira média (PM). Materiais e Métodos: Para isso, foi conduzido ao longo de dois anos agrícolas experimento no campo experimental da Embrapa no município de Ouro Preto do Oeste-RO, para a avaliação da peneira média de 130 genótipos (clones) com características das variedades botânicas Conilon, Robusta e híbridos intervarietais. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições de quatro plantas por parcela. Resultados: Não houve resultados significativos para a interação clones X anos, indicando uma maior consistência no comportamento das plantas ao longo do tempo. Porém foram observadas diferenças significativas para o tamanho dos grãos entre os genótipos avaliados, possibilitando selecionar genótipos superiores. Conclusão: Os genótipos agruparam-se em cinco classes de acordo com o teste de média, subsidiando a caracterização de um gradiente de variabilidade da característica avaliada ABSTRACTIntroduction: Coffea canephora accounts for approximately 35% of the world's coffee production. The state of Rondônia stands out as a traditional coffee producer, being the second largest Brazilian producer of C. canephora. In the classical genetic improvement of C. anephora, the selection of plants of high average sieve is associated with a drink of superior quality. Objectives: The objective of this udy was to evaluate the genetic variability of Coffea canephora clones for the agronomic medium sieve (PM). Materials and Methods: The experiment was conducted in the experimental field of Embrapa, municipality of OuroPreto do Oeste-RO, located at coordinates 10º44'53 "S and 62º12'57". One hundred thirty genotypes (clones) of botanical characteristics Conilon, Robusta and intervarietal hybrids were evaluated in the agricultural years 2013-2014 and 2014-2015. The experimental design was a randomized block design with four blocks and four plants per plot, spacing 3.5 x 1.5 meters between plants. Results: Significant difference was found for the grain size. According to the F test, at 5% probability, the genotypes were grouped into five classes according to the mean test. Conclusion: The results obtained subsidized the characterization of a variability gradient of the evaluated trait.

scholarly journals Molecular Characterization of hobo-Mediated Inversions in Drosophila melanogaster

Genetics ◽  
1996 ◽  
Vol 144 (2) ◽  
pp. 647-656
Author(s):  
William B Eggleston ◽  
Nac R Rim ◽  
Johng K Lim
Keyword(s):  
X Chromosome ◽  
Polymerase Chain Reaction Amplification ◽  
Polytene Chromosomes ◽  
Chromosomal Inversions ◽  
Hobo Element ◽  
Reaction Amplification ◽  
Notch Locus ◽  
Polymerase Chain

Abstract The structure of chromosomal inversions mediated by hobo transposable elements in the Uc-1 X chromosome was investigated using cytogenetic and molecular methods. Uc-1 contains a phenotypically silent hobo element inserted in an intron of the Notch locus. Cytological screening identified six independent Notch mutations resulting from chromosomal inversions with one breakpoint at cytological position 3C7, the location of Notch. In situ hybridization to salivary gland polytene chromosomes determined that both ends of each inversion contained hobo and Notch sequences. Southern blot analyses showed that both breakpoints in each inversion had hobo-Notch junction fragments indistinguishable in structure from those present in the Uc-1 X chromosome prior to the rearrangements. Polymerase chain reaction amplification of the 12 hobo-Notch junction fragments in the six inversions, followed by DNA sequence analysis, determined that each was identical to one of the two hobo-Notch junctions present in Uc-1. These results are consistent with a model in which hobo-mediated inversions result from homologous pairing and recombination between a pair of hobo elements in reverse orientation.

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