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1.
Sci Rep ; 14(1): 13582, 2024 06 12.
Article in English | MEDLINE | ID: mdl-38866814

ABSTRACT

Giardia duodenalis, a major cause of waterborne infection, infects a wide range of mammalian hosts and is subdivided into eight genetically well-defined assemblages named A through H. However, fragmented genomes and a lack of comparative analysis within and between the assemblages render unclear the molecular mechanisms controlling host specificity and differential disease outcomes. To address this, we generated a near-complete de novo genome of AI assemblage using the Oxford Nanopore platform by sequencing the Be-2 genome. We generated 148,144 long-reads with quality scores of > 7. The final genome assembly consists of only nine contigs with an N50 of 3,045,186 bp. This assembly agrees closely with the assembly of another strain in the AI assemblage (WB-C6). However, a critical difference is that a region previously placed in the five-prime region of Chr5 belongs to Chr4 of Be-2. We find a high degree of conservation in the ploidy, homozygosity, and the presence of cysteine-rich variant-specific surface proteins (VSPs) within the AI assemblage. Our assembly provides a nearly complete genome of a member of the AI assemblage of G. duodenalis, aiding population genomic studies capable of elucidating Giardia transmission, host range, and pathogenicity.


Subject(s)
Genome, Protozoan , Genomics , Giardia lamblia , Giardia lamblia/genetics , Humans , Genomics/methods , Giardiasis/parasitology , Giardiasis/genetics , Homozygote , Protozoan Proteins/genetics , Animals , Phylogeny , Conserved Sequence
2.
Sci Rep ; 14(1): 12253, 2024 05 28.
Article in English | MEDLINE | ID: mdl-38806545

ABSTRACT

Overexpression of Glycine max disease resistant 1 (GmDR1) exhibits broad-spectrum resistance against Fusarium virguliforme, Heterodera glycines (soybean cyst nematode), Tetranychus urticae (Koch) (spider mites), and Aphis glycines Matsumura (soybean aphids) in soybean. To understand the mechanisms of broad-spectrum immunity mediated by GmDR1, the transcriptomes of a strong and a weak GmDR1-overexpressor following treatment with chitin, a pathogen- and pest-associated molecular pattern (PAMP) common to these organisms, were investigated. The strong and weak GmDR1-overexpressors exhibited altered expression of 6098 and 992 genes, respectively, as compared to the nontransgenic control following chitin treatment. However, only 192 chitin- and 115 buffer-responsive genes exhibited over two-fold changes in expression levels in both strong and weak GmDR1-overexpressors as compared to the control. MapMan analysis of the 192 chitin-responsive genes revealed 64 biotic stress-related genes, of which 53 were induced and 11 repressed as compared to the control. The 53 chitin-induced genes include nine genes that encode receptor kinases, 13 encode nucleotide-binding leucine-rich repeat (NLR) receptor proteins, seven encode WRKY transcription factors, four ethylene response factors, and three MYB-like transcription factors. Investigation of a subset of these genes revealed three receptor protein kinases, seven NLR proteins, and one WRKY transcription factor genes that are induced following F. virguliforme and H. glycines infection. The integral plasma membrane GmDR1 protein most likely recognizes PAMPs including chitin and activates transcription of genes encoding receptor kinases, NLR proteins and defense-related genes. GmDR1 could be a pattern recognition receptor that regulates the expression of several NLRs for expression of PAMP-triggered immunity and/or priming the effector triggered immunity.


Subject(s)
Disease Resistance , Gene Expression Regulation, Plant , Glycine max , NLR Proteins , Plant Diseases , Plant Proteins , Glycine max/parasitology , Glycine max/genetics , Disease Resistance/genetics , Plant Diseases/parasitology , Plant Diseases/microbiology , Plant Diseases/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , NLR Proteins/metabolism , NLR Proteins/genetics , Animals , Fusarium , Chitin/metabolism , Cell Membrane/metabolism , Transcriptome , Plants, Genetically Modified
3.
Sci Rep ; 13(1): 22802, 2023 12 20.
Article in English | MEDLINE | ID: mdl-38129566

ABSTRACT

Eimeria tenella is a major cause of caecal coccidiosis in commercial poultry chickens worldwide. Here, we report chromosomal scale assembly of Eimeria tenella strain APU2, a strain isolated from commercial broiler chickens in the U.S. We obtained 100× sequencing Oxford Nanopore Technology (ONT) and more than 800× Coverage of Illumina Next-Seq. We created the assembly using the hybrid approach implemented in MaSuRCA, achieving a contiguous 51.34 Mb chromosomal-scale scaffolding enabling identification of structural variations. The AUGUSTUS pipeline predicted 8060 genes, and BUSCO deemed the genomes 99% complete; 6278 (78%) genes were annotated with Pfam domains, and 1395 genes were assigned GO-terms. Comparing E. tenella strains (APU2, US isolate and Houghton, UK isolate) derived Houghton strain of E. tenella revealed 62,905 high stringency differences, of which 45,322 are single nucleotide polymorphisms (SNPs) (0.088%). The rate of transitions/transversions among the SNPs are 1.63 ts/tv. The strains possess conserved gene order but have profound sequence heterogeneity in a several chromosomal segments (chr 2, 11 and 15). Genic and intergenic variation in defined gene families was evaluated between the two strains to possibly identify sequences under selection. The average genic nucleotide diversity of 2.8 with average 2 kb gene length (0.145%) at genic level. We examined population structure using available E. tenella sequences in NCBI, revealing that the two E. tenella isolates from the U.S. (E. tenella APU2 and Wisconsin, "ERR296879") share a common maternal inheritance with the E. tenella Houghton. Our chromosomal level assembly promotes insight into Eimeria biology and evolution, hastening drug discovery and vaccine development.


Subject(s)
Coccidiosis , Eimeria tenella , Eimeria , Parasites , Poultry Diseases , Animals , Eimeria tenella/genetics , Chickens/parasitology , Eimeria/genetics , Coccidiosis/veterinary , Coccidiosis/parasitology
4.
Plant Dis ; 107(4): 987-998, 2023 Apr.
Article in English | MEDLINE | ID: mdl-35900347

ABSTRACT

Phytophthora, with 203 species, is a genus of high importance in agriculture worldwide. Here, we present the online resource "IDphy", developed to facilitate the correct identification of species of Phytophthora using the type specimens from the original descriptions wherever possible. IDphy emphasizes species of high economic impact and regulatory concern for the United States. IDphy presents an interactive Lucid key and a tabular key for 161 culturable species described as of May 2018, including 141 ex-types and 20 well-authenticated specimens. IDphy contains standard operating procedures for morphological and molecular characterization, as well as a glossary, image gallery, and numerous links. Each of the 161 factsheets includes access to nomenclature and morphological and molecular features, including sequences of the internal transcribed spacer ribosomal DNA, cytochrome C oxidase subunit I (barcoding genes), YPT1, ß-tubulin, elongation factor 1a, L10, heat shock protein 90, and other genes. IDphy contains an innovative in silico BLAST and phylogenetic sequence analysis using NCBI. The IDphy mobile app, released in August 2021 (free for Android or iOS), allows users to take the Lucid key into the laboratory. IDphy is the first online identification tool based on the ex-types implemented for plant pathogens. In this article, we also include information for 21 new species and one hybrid described after the publication of IDphy, the status of the specimens of the types and ex-types at international herbaria and culture collections, and the status of genomes at the GenBank (currently 153 genome assemblies which correspond to 42 described species, including 16 ex-types). The effectiveness of the IDphy online resource and the content of this article could inspire other researchers to develop additional identification tools for other important groups of plant pathogens.


Subject(s)
Phytophthora , Phytophthora/genetics , Phylogeny , DNA, Ribosomal Spacer/genetics , DNA, Ribosomal/genetics , DNA, Intergenic
5.
Proc Inst Mech Eng H ; 236(8): 1216-1231, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35821645

ABSTRACT

Magnetic Resonance Imaging (MRI) is an essential clinical tool for detecting the abnormalities such as tumors and clots in the human brain. The brain MR images are contaminated by artifacts and noise that follow Rician distribution during the acquisition process. It causes the loss of fine details information, distortion, and a blurred vision of the image. A reshaped Gabor filter-based denoising technique is proposed to overcome these issues. To develop the reshaped Gabor filter, the range of reshaping parameters of the filter is initially obtained by a random search method. Further, to evaluate the better performance of the proposed filter, a manual search is used to find the optimal parametric values and tested on T1, T2, and PD weighted MR data sets one by one. Also, the proposed technique is compared with the existing state of the art filtering methods such as Wiener, Median, Partial differential equation (PDE), Anisotropic diffusion filter (ADF), Non-local means filter (NLM), Modified complex diffusion filter (MCD), Multichannel residual learning of CNN (MRL), Maximum a posteriori (MAP), Adaptive non-local means algorithm (ADNLM), and Advance NLM filtering with non-sub sampled (AVNLMNS) on the basic reference and no reference parameter. The parameters such as mean square error (MSE), peak signal to noise ratio (PSNR), structural similarity index metric (SSIM), perception-based image quality evaluator (PIQE), and blind/referenceless image spatial quality evaluator (BRISQE) are evaluated on T1, T2, and PD weighted MR images with different noise variances such as 1%, 3%, 5%, 7%, and 9%. The proposed method may be used as a better denoising scheme for Rician distributed noise, edge preservation, fine details restoration, and enhancement of abnormalities.


Subject(s)
Brain , Magnetic Resonance Imaging , Algorithms , Artifacts , Brain/diagnostic imaging , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Signal-To-Noise Ratio
7.
Proc Inst Mech Eng H ; 236(7): 1036-1053, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35491993

ABSTRACT

Breast cancer is an extremely aggressive cancer in women. Its abnormalities can be observed in the form of masses, calcification and lumps. In order to reduce the mortality rate of women its detection is needed at an early stage. The present paper proposes a novel bi-modal extended Huber loss function based refined mask regional convolutional neural network for automatic multi-instance detection and localization of breast cancer. To refine and increase the efficacy of the proposed method three changes are casted. First, a pre-processing step is performed for mammogram and ultrasound breast images. Second, the features of the region proposal network are separately mapped for accurate region of interest. Third, to reduce overfitting and fast convergence, an extended Huber loss function is used at the place of SmoothL1(x) in boundary loss. To extend the functionality of Huber loss, the delta parameter is automated by the aid of median absolute deviation with grid search algorithm. It provides the best optimum value of delta instead of user-based value. The proposed method is compared with pre-existing methods in terms of accuracy, true positive rate, true negative rate, precision, F-score, balanced classification rate, Youden's index, Jaccard Index and dice coefficient on CBIS-DDSM and ultrasound database. The experimental result shows that the proposed method is a better suited approach for multi-instance detection, localization and classification of breast cancer. It can be used as a diagnostic medium that helps in clinical purposes and leads to a precise diagnosis of breast cancer abnormalities.


Subject(s)
Breast Neoplasms , Algorithms , Breast/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Databases, Factual , Female , Humans , Mammography/methods , Neural Networks, Computer
8.
Phytopathology ; 112(4): 953-955, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34664973

ABSTRACT

Phytophthora is one of the most important genera of plant pathogens, with many members causing high economic losses worldwide. To build robust molecular identification systems, it is very important to have information from well-authenticated specimens and, in preference, the ex-type specimens. The reference genomes of well-authenticated specimens form a critical foundation for genetics, biological research, and diagnostic applications. In this study, we describe four draft Phytophthora genome resources for the ex-type of Phytophthora citricola BL34 (P0716 WPC) (118 contigs for 50 Mb), and well-authenticated specimens of P. syringae BL57G (P10330 WPC) (591 contigs for 75 Mb), P. hibernalis BL41G (P3822 WPC) (404 contigs for 84 Mb), and P. nicotianae BL162 (P6303 WPC) (3,984 contigs for 108 Mb) generated with MinION long-read high-throughput sequencing technology (Oxford Nanopore Technologies). Using the quality reads, we assembled high-coverage genomes of P. citricola with 291× coverage and 16,662 annotated genes; P. nicotianae with 205× coverage and 29,271 annotated genes; P. syringae with 76× coverage and 23,331 annotated genes, and P. hibernalis with 42× coverage and 21,762 annotated genes. With the availability of genome sequences and their annotations, we predict that these draft genomes will be accommodating for various basic and applied research, including diagnostics to protect global agriculture.


Subject(s)
Phytophthora , High-Throughput Nucleotide Sequencing , Phytophthora/genetics , Plant Diseases
9.
Proc Inst Mech Eng H ; 236(1): 12-29, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34405743

ABSTRACT

Ultrasound is a well-known imaging modality for the interpretation of breast cancer. It is playing very important role for breast cancer detection that are missed by mammograms. The image acquisition is usually affected by the presence of noise, artifacts, and distortion. To overcome such type of issues, there is a need of image restoration and enhancement to improve the quality of image. This paper proposes a single framework for denoising and enhancement of ultrasound images, where a smoothing filter is replaced with an extended complex diffusion-based filter in an unsharp masking technique. The performance evaluation of the proposed method is tested on real ultrasound breast cancer images database and synthetic ultrasound image. The performance evaluation comprises qualitative and quantitative evaluation along with comparative analysis of pre-existing and proposed method. The quantitative evaluation metrics are mean squared error, peak-signal-to-noise ratio, correlation parameter, normalized absolute error, universal quality index, similarity structure index, edge preservation index, a measure of enhancement, a measure of enhancement by entropy, and second derivative like measurement. The result specifies that the proposed method is better suited approach for the removal of speckle noise which follows Rayleigh distribution, restoration of information, enhancement of abnormalities, and proper edge preservation.


Subject(s)
Artifacts , Image Enhancement , Algorithms , Signal-To-Noise Ratio , Ultrasonography
10.
Proc Inst Mech Eng H ; 235(6): 615-624, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33784847

ABSTRACT

Adults born after 1970s are more prone to cardiovascular diseases. Death rate percentage is quite high due to heart related diseases. Therefore, there is necessity to enquire the problem or detection of heart diseases earlier for their proper treatment. As, Valvular heart disease, that is, stenosis and regurgitation of heart valve, are also a major cause of heart failure; which can be diagnosed at early-stage by detection and analysis of heart sound signal, that is, HS signal. In this proposed work, an attempt has been made to detect and localize the major heart sounds, that is, S1 and S2. The work in this article consists of three parts. Firstly, self-acquisition of Phonocardiogram (PCG) and Electrocardiogram (ECG) signal through a self-assembled, data-acquisition set-up. The Phonocardiogram (PCG) signal is acquired from all the four auscultation areas, that is, Aortic, Pulmonic, Tricuspid and Mitral on human chest, using electronic stethoscope. Secondly, the major heart sounds, that is, S1 and S2are detected using 3rd Order Normalized Average Shannon energy Envelope (3rd Order NASE) Algorithm. Further, an auto-thresholding has been used to localize time gates of S1 and S2 and that of R-peaks of simultaneously recorded ECG signal. In third part; the successful detection rate of S1 and S2, from self-acquired PCG signals is computed and compared. A total of 280 samples from same subjects as well as from different subjects (of age group 15-30 years) have been taken in which 70 samples are taken from each auscultation area of human chest. Moreover, simultaneous recording of ECG has also been performed. It was analyzed and observed that detection and localization of S1 and S2 found 74% successful for the self-acquired heart sound signal, if the heart sound data is recorded from pulmonic position of Human chest. The success rate could be much higher, if standard data base of heart sound signal would be used for the same analysis method. The, remaining three auscultations areas, that is, Aortic, Tricuspid, and Mitral have smaller success rate of detection of S1 and S2 from self-acquired PCG signals. So, this work justifies that the Pulmonic position of heart is most suitable auscultation area for acquiring PCG signal for detection and localization of S1 and S2 much accurately and for analysis purpose.


Subject(s)
Heart Sounds , Algorithms , Heart , Heart Auscultation , Humans , Phonocardiography , Signal Processing, Computer-Assisted
12.
Environ Sci Pollut Res Int ; 28(4): 3880-3887, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32488698

ABSTRACT

In this paper, we present the studies on electromagnetic interference (EMI) shielding effectiveness (SE) of K2CrO4-PMMA composites developed by two different methods: one in bulk form of thickness 1.2 mm and another by stacking twelve layers of thin films each of thickness 100 µm. The EMI SE of stacked twelve layers of 1.2-mm-thick composite films has been achieved until 23.2 dB in the frequency range 8.0-12.0 GHz. This is remarkably higher than the 17 dB achieved for the bulk composites of 1.2 mm thickness. The characteristic EMI SE graphs obtained using Agilent E82B Vector Network Analyzer in the X band frequency range have been depicted, and the shielding mechanism in these composites has been analyzed. It is found that the SE in this frequency range is dominated by absorption. The study suggests these composites to be a potentially promising material for EMI shielding purpose.


Subject(s)
Nanotubes, Carbon , Polymers , Electromagnetic Fields , Oxides
13.
Phytopathology ; 111(3): 593-596, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32865468

ABSTRACT

Whole genome sequence (WGS) based identifications are being increasingly used by regulatory and public health agencies to facilitate the detection, investigation, and control of pathogens and pests. Fusarium oxysporum f. sp. vasinfectum is a significant vascular wilt pathogen of cultivated cotton and consists of several pathogenic races that are not each other's closest phylogenetic relatives. We have developed WGS assemblies for isolates of F. oxysporum f. sp. vasinfectum race 1 (FOV1), race 4 (FOV4), race 5 (FOV5), and race 8 (FOV8) using a combination of Nanopore (MinION) and Illumina sequencing technology (Mi-Seq). This resulted in assembled contigs with more than 100× coverage for each of the F. oxysporum f. sp. vasinfectum races and estimated genome sizes of FOV1 52 Mb, FOV4 68 Mb, FOV5 68 Mb, and FOV8 55 Mb. The AUGUSTUS gene prediction program predicted 16,263 genes in FOV1, 20,259 genes in FOV4, 20,375 genes in FOV5 and 16,615 genes in FOV8. We were able to identify 525 genes unique to FOV1, 570 unique to FOV4, 1,242 unique to FOV5, and 383 unique to FOV8. We expect that these findings will help in comparative genomics and in the identification of unique genes as candidate targets for diagnostic marker and methods development to permit rapid differentiation of F. oxysporum f. sp. vasinfectum subgroups.


Subject(s)
Fusarium , Fusarium/genetics , Phylogeny , Plant Diseases , Quantitative Trait Loci
14.
Mol Plant Microbe Interact ; 33(6): 794-797, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32129709

ABSTRACT

Phytophthora ramorum, P. kernoviae, and P. melonis are each species of current regulatory concern in the United States, the United Kingdom, and other areas of the world. Ex-type material are cultures and duplicates of the type that was used to describe each species and that are deposited in additional culture collections. Using these type specimens as references is essential to designing correct molecular identification and diagnostic systems. Here, we report a whole genome sequence for the Ex-type material of P. ramorum, P. kernoviae, and P. melonis generated using high-throughput sequencing via the MinION third generation platform from Oxford Nanopore Technology. We assembled the quality filtered reads into contigs for each species. We assembled the continuous contigs of P. ramorum, P. kernoviae, and P. melonis (1,322, 545, and 2,091 contigs, respectively). The ab initio prediction of genes from these species reveals that there are 16,838, 12,793, and 34,580 genes in P. ramorum, P. kernoviae, and P. melonis, respectively. Of the 34,580 P. melonis genes, 10,164 genes were conserved among all three of these Phytophthora species which may include pathogenicity genes. We compared the ex-type of P. ramorum EU1 lineage assembly with another selected isolate of EU1 available at the National Center for Biotechnology Information and found 251,859 single nucleotide polymorphisms (SNPs) genome-wide; the comparison with the EU2 lineage genome isolate revealed 441,859 SNPs genome-wide. This genome resource of the ex-types of P. ramorum, and P. kernoviae is a significant contribution as these species are among the most important pathogens of regulatory concern in different regions of the world.


Subject(s)
Genome , Nanopore Sequencing , Phytophthora/genetics , Plant Diseases/parasitology , Contig Mapping , High-Throughput Nucleotide Sequencing , Polymorphism, Single Nucleotide
15.
Genomics ; 111(4): 629-635, 2019 07.
Article in English | MEDLINE | ID: mdl-29626511

ABSTRACT

Salt stress causes foliar chlorosis and scorch, plant stunting, and eventually yield reduction in soybean. There are differential responses, namely tolerance (excluder) and intolerance (includer), among soybean germplasm. However, the genetic and physiological mechanisms for salt tolerance is complex and not clear yet. Based on the results from the screening of the RA-452 x Osage mapping population, two F4:6 lines with extreme responses, most tolerant and most sensitive, were selected for a time-course gene expression study in which the 250 mM NaCl treatment was initially imposed at the V1 stage and continued for 24 h (hrs). Total RNA was isolated from the leaves harvested at 0, 6, 12, 24 h after the initiation of salt treatment, respectively. The RNA-Seq analysis was conducted to compare the salt tolerant genotype with salt sensitive genotype at each time point using RNA-Seq pipeline method. A total of 2374, 998, 1746, and 630 differentially expressed genes (DEGs) between salt-tolerant line and salt-sensitive line, were found at 0, 6, 12, and 24 h, respectively. The expression patterns of 154 common DEGs among all the time points were investigated, of which, six common DEGs were upregulated and seven common DEGs were downregulated in salt-tolerant line. Moreover, 13 common DEGs were dramatically expressed at all the time points. Based on Log2 (fold change) of expression level of salt-tolerant line to salt-sensitive line and gene annotation, Glyma.02G228100, Glyma.03G226000, Glyma.03G031000, Glyma.03G031400, Glyma.04G180300, Glyma.04G180400, Glyma.05 g204600, Glyma.08G189600, Glyma.13G042200, and Glyma.17G173200, were considered to be the key potential genes involving in the salt-tolerance mechanism in the soybean salt-tolerant line.


Subject(s)
Glycine max/genetics , Salt Tolerance , Transcriptome , Gene Expression Regulation, Plant , Genotype , Glycine max/physiology
16.
Rev Sci Instrum ; 90(12): 123903, 2019 Dec 01.
Article in English | MEDLINE | ID: mdl-31893822

ABSTRACT

Three indigenous systems-the underwater arc discharge setup, the inert environment arc discharge system, and the chemical vapor deposition (CVD) system-for the gram-scale production of carbon nanotubes were designed and fabricated. In this study, a detailed description of the development and fabrication of these systems is given. Carbon nanotubes were synthesized by using all the three systems, and comparative analyses of the morphology, composition, and purity were done. The synthesized materials were characterized using scanning electron microscopy, X-ray diffraction (XRD), and Raman spectroscopy. The scanning electron microscopy images show agglomerated tubed fiberlike structures in samples from the arc discharge setup, whereas samples from the CVD system do not show any tubelike structures decorated around the carbon nanotubes. Structural investigations done using powder XRD revealed the presence of the hexagonal crystallographic phase. Furthermore, the presence of the G and 2D bands reveals sp2 hybridization and confirms the presence of carbon nanotubes in samples. In conclusion, carbon nanotubes synthesized via the CVD system is of high quality and quantity. Moreover, the CVD is a cheap, easy to operate, and energy-saving synthesis method compared with the other two methods.

17.
Phytopathology ; 108(10): 1141-1142, 2018 10.
Article in English | MEDLINE | ID: mdl-29723113

ABSTRACT

Fungi in the genus Monilinia cause brown rot disease of stone and pome fruits. Here, we report the draft genome assemblies of four important phytopathogenic species: M. fructicola, M. fructigena, M. polystroma, and M. laxa. The draft genome assemblies were 39 Mb (M. fructigena), 42 Mb (M. laxa), 43 Mb (M. fructicola), and 45 Mb (M. polystroma) with as few as 550 contigs (M. laxa). These are the first draft genome resources publicly available for M. laxa, M. fructigena, and M. polystroma.


Subject(s)
Ascomycota/genetics , Genome, Fungal , Plant Diseases/microbiology , Rosaceae/microbiology
18.
PLoS One ; 13(4): e0195488, 2018.
Article in English | MEDLINE | ID: mdl-29672568

ABSTRACT

Amaranthus palmeri (Amaranthaceae) is a noxious weed in several agroecosystems and in some cases seriously threatens the sustainability of crop production in North America. Glyphosate-resistant Amaranthus species are widespread, prompting the use of alternatives to glyphosate such as glufosinate, in conjunction with glufosinate-resistant crop cultivars, to help control glyphosate-resistant weeds. An experiment was conducted to analyze the transcriptome of A. palmeri plants that survived exposure to 0.55 kg ha-1 glufosinate. Since there was no record of glufosinate use at the collection site, survival of plants within the population are likely due to genetic expression that pre-dates selection; in the formal parlance of weed science this is described as natural tolerance. Leaf tissues from glufosinate-treated and non-treated seedlings were harvested 24 h after treatment (HAT) for RNA-Seq analysis. Global gene expression was measured using Illumina DNA sequence reads from non-treated and treated surviving (presumably tolerant, T) and susceptible (S) plants. The same plants were used to determine the mechanisms conferring differential tolerance to glufosinate. The S plants accumulated twice as much ammonia as did the T plants, 24 HAT. The relative copy number of the glufosinate target gene GS2 did not differ between T and S plants, with 1 to 3 GS2 copies in both biotypes. A reference cDNA transcriptome consisting of 72,780 contigs was assembled, with 65,282 sequences putatively annotated. Sequences of GS2 from the transcriptome assembly did not have polymorphisms unique to the tolerant plants. Five hundred sixty-seven genes were differentially expressed between treated T and S plants. Of the upregulated genes in treated T plants, 210 were more highly induced than were the upregulated genes in the treated S plants. Glufosinate-tolerant plants had greater induction of ABC transporter, glutathione S-transferase (GST), NAC transcription factor, nitronate monooxygenase (NMO), chitin elicitor receptor kinase (CERK1), heat shock protein 83, ethylene transcription factor, heat stress transcription factor, NADH-ubiquinone oxidoreductase, ABA 8'-hydroxylase, and cytochrome P450 genes (CYP72A, CYP94A1). Seven candidate genes were selected for validation using quantitative real time-PCR. While GST was upregulated in treated tolerant plants in at least one population, CYP72A219 was consistently highly expressed in all treated tolerant biotypes. These genes are candidates for contributing tolerance to glufosinate. Taken together, these results show that differential induction of stress-protection genes in a population can enable some individuals to survive herbicide application. Elevated expression of detoxification-related genes can get fixed in a population with sustained selection pressure, leading to evolution of resistance. Alternatively, sustained selection pressure could select for mutation(s) in the GS2 gene with the same consequence.


Subject(s)
Amaranthus/drug effects , Amaranthus/metabolism , Glycine/analogs & derivatives , Herbicide Resistance/physiology , Herbicides/pharmacology , Transcriptome/drug effects , Ammonia/metabolism , Biomass , Dose-Response Relationship, Drug , Gene Dosage , Gene Expression Profiling , Gene Expression Regulation, Plant/drug effects , Glutamate-Ammonia Ligase/metabolism , Glycine/pharmacology , Phenotype , Plant Leaves/drug effects , Plant Leaves/metabolism , Plant Proteins/metabolism , Plant Weeds/drug effects , Plant Weeds/genetics , Plant Weeds/metabolism , Seedlings/drug effects , Seedlings/metabolism , Sequence Analysis, Protein , Sequence Analysis, RNA , Glyphosate
19.
J Xray Sci Technol ; 26(1): 29-49, 2018.
Article in English | MEDLINE | ID: mdl-29480232

ABSTRACT

Nowadays, huge number of mammograms has been generated in hospitals for the diagnosis of breast cancer. Content-based image retrieval (CBIR) can contribute more reliable diagnosis by classifying the query mammograms and retrieving similar mammograms already annotated by diagnostic descriptions and treatment results. Since labels, artifacts, and pectoral muscles present in mammograms can bias the retrieval procedures, automated detection and exclusion of these image noise patterns and/or non-breast regions is an essential pre-processing step. In this study, an efficient and automated CBIR system of mammograms was developed and tested. First, the pre-processing steps including automatic labelling-artifact suppression, automatic pectoral muscle removal, and image enhancement using the adaptive median filter were applied. Next, pre-processed images were segmented using the co-occurrence thresholds based seeded region growing algorithm. Furthermore, a set of image features including shape, histogram based statistical, Gabor, wavelet, and Gray Level Co-occurrence Matrix (GLCM) features, was computed from the segmented region. In order to select the optimal features, a minimum redundancy maximum relevance (mRMR) feature selection method was then applied. Finally, similar images were retrieved using Euclidean distance similarity measure. The comparative experiments conducted with reference to benchmark mammographic images analysis society (MIAS) database confirmed the effectiveness of the proposed work concerning average precision of 72% and 61.30% for normal & abnormal classes of mammograms, respectively.


Subject(s)
Breast Neoplasms/diagnostic imaging , Mammography/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Artifacts , Female , Humans
20.
Plant Physiol ; 176(1): 865-878, 2018 01.
Article in English | MEDLINE | ID: mdl-29101280

ABSTRACT

Nonhost resistance is defined as the immunity of a plant species to all nonadapted pathogen species. Arabidopsis (Arabidopsis thaliana) ecotype Columbia-0 is nonhost to the oomycete plant pathogen Phytophthora sojae and the fungal plant pathogen Fusarium virguliforme that are pathogenic to soybean (Glycine max). Previously, we reported generating the pss1 mutation in the pen1-1 genetic background as well as genetic mapping and characterization of the Arabidopsis nonhost resistance Phytophthora sojae-susceptible gene locus, PSS1 In this study, we identified six candidate PSS1 genes by comparing single-nucleotide polymorphisms of (1) the bulked DNA sample of seven F2:3 families homozygous for the pss1 allele and (2) the pen1-1 mutant with Columbia-0. Analyses of T-DNA insertion mutants for each of these candidate PSS1 genes identified the At3g59640 gene encoding a glycine-rich protein as the putative PSS1 gene. Later, complementation analysis confirmed the identity of At3g59640 as the PSS1 gene. PSS1 is induced following P. sojae infection as well as expressed in an organ-specific manner. Coexpression analysis of the available transcriptomic data followed by reverse transcriptase-polymerase chain reaction suggested that PSS1 is coregulated with ATG8a (At4g21980), a core gene in autophagy. PSS1 contains a predicted single membrane-spanning domain. Subcellular localization study indicated that it is an integral plasma membrane protein. Sequence analysis suggested that soybean is unlikely to contain a PSS1-like defense function. Following the introduction of PSS1 into the soybean cultivar Williams 82, the transgenic plants exhibited enhanced resistance to F. virguliforme, the pathogen that causes sudden death syndrome.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/immunology , Arabidopsis/metabolism , Cell Membrane/metabolism , Disease Resistance , Glycine max/genetics , Membrane Proteins/metabolism , Plant Diseases/immunology , Arabidopsis/genetics , Arabidopsis/microbiology , Arabidopsis Proteins/genetics , Gene Expression Regulation, Plant , Genes, Plant , Genetic Complementation Test , Membrane Proteins/genetics , Mutation/genetics , Phylogeny , Phytophthora/physiology , Plant Diseases/microbiology , Plants, Genetically Modified
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