Pathogen- or microbe-associated molecular patterns (PAMPs MAMPs) are detected as nonself by host pattern recognition receptors (PRRs) and activate pattern-triggered immunity (PTI). Microbial ...invasions often trigger the production of host-derived endogenous signals referred to as danger- or damage-associated molecular patterns (DAMPs), which are also perceived by PRRs to modulate PTI responses. Collectively, PTI contributes to host defense against infections by a broad range of pathogens. Remarkable progress has been made toward demonstrating the cellular and physiological responses upon pattern recognition, elucidating the molecular, biochemical, and genetic mechanisms of PRR activation, and dissecting the complex signaling networks that orchestrate PTI responses. In this review, we present an update on the current understanding of how plants recognize and respond to nonself patterns, a process from which the seemingly chaotic responses form into a harmonic defense.
This book considers classical and current theory and practice, of supervised, unsupervised and semi-supervised pattern recognition, to build a complete background for professionals and students of ...engineering. The authors, leading experts in the field of pattern recognition, have provided an up-to-date, self-contained volume encapsulating this wide spectrum of information. The very latest methods are incorporated in this edition: semi-supervised learning, combining clustering algorithms, and relevance feedback. · Thoroughly developed to include many more worked examples to give greater understanding of the various methods and techniques · Many more diagrams included--now in two color--to provide greater insight through visual presentation · Matlab code of the most common methods are given at the end of each chapter. · More Matlab code is available, together with an accompanying manual, via this site · Latest hot topics included to further the reference value of the text including non-linear dimensionality reduction techniques, relevance feedback, semi-supervised learning, spectral clustering, combining clustering algorithms. · An accompanying book with Matlab code of the most common methods and algorithms in the book, together with a descriptive summary, and solved examples including real-life data sets in imaging, and audio recognition. The companion book will be available separately or at a special packaged price (ISBN: 9780123744869).
Thoroughly developed to include many more worked examples to give greater understanding of the various methods and techniques Many more diagrams included--now in two color--to provide greater insight through visual presentation Matlab code of the most common methods are given at the end of each chapter An accompanying book with Matlab code of the most common methods and algorithms in the book, together with a descriptive summary and solved examples, and including real-life data sets in imaging and audio recognition. The companion book is available separately or at a special packaged price (Book ISBN: 9780123744869. Package ISBN: 9780123744913) Latest hot topics included to further the reference value of the text including non-linear dimensionality reduction techniques, relevance feedback, semi-supervised learning, spectral clustering, combining clustering algorithms Solutions manual, powerpoint slides, and additional resources are available to faculty using the text for their course. Register at www.textbooks.elsevier.com and search on "Theodoridis" to access resources for instructor.
Summary
Plants have evolved a repertoire of monitoring systems to sense plant morphogenesis and to face environmental changes and threats caused by different attackers. These systems integrate ...different signals into overreaching triggering pathways which coordinate developmental and defence‐associated responses. The plant cell wall, a dynamic and complex structure surrounding every plant cell, has emerged recently as an essential component of plant monitoring systems, thus expanding its function as a passive defensive barrier. Plants have a dedicated mechanism for maintaining cell wall integrity (CWI) which comprises a diverse set of plasma membrane‐resident sensors and pattern recognition receptors (PRRs). The PRRs perceive plant‐derived ligands, such as peptides or wall glycans, known as damage‐associated molecular patterns (DAMPs). These DAMPs function as ‘danger’ alert signals activating DAMP‐triggered immunity (DTI), which shares signalling components and responses with the immune pathways triggered by non‐self microbe‐associated molecular patterns that mediate disease resistance. Alteration of CWI by impairment of the expression or activity of proteins involved in cell wall biosynthesis and/or remodelling, as occurs in some plant cell wall mutants, or by wall damage due to colonization by pathogens/pests, activates specific defensive and growth responses. Our current understanding of how these alterations of CWI are perceived by the wall monitoring systems is scarce and few plant sensors/PRRs and DAMPs have been characterized. The identification of these CWI sensors and PRR–DAMP pairs will help us to understand the immune functions of the wall monitoring system, and might allow the breeding of crop varieties and the design of agricultural strategies that would enhance crop disease resistance.
Significance Statement
The plant cell wall has emerged as an essential component of plant stress‐monitoring systems, thus expanding its function as a passive defensive barrier. Here we review current knowledge about the systems that monitor plant cell wall integrity and their functions in triggering specific disease resistance and growth responses.
Local descriptors used in face recognition are robust in a sense that these descriptors perform well in varying pose, illumination, and lighting conditions. The accuracy of these descriptors depends ...on the precision of mapping the relationship that exists in the local neighborhood of a facial image into microstructures. In this paper, a local gradient hexa pattern is proposed that identifies the relationship among the reference pixel and its neighboring pixels at different distances across different derivative directions. Discriminative information exists in the local neighborhood as well as in different derivative directions. The proposed descriptor effectively transforms these relationships into binary micropatterns discriminating inter-class facial images with optimal precision. The recognition and retrieval performance of the proposed descriptor has been compared with state-of-the-art descriptors, namely, local derivative pattern, local tetra pattern, multiblock local binary pattern, and local vector pattern over the most challenging and benchmark facial image databases, i.e., Cropped Extended Yale B, CMU-PIE, color-FERET, LFW, and Ghallager database. The proposed descriptor has better recognition as well as retrieval rates compared with state-of-the-art descriptors.
Perception of pathogen (or microbe)‐associated molecular patterns (PAMPs/MAMPs) by pattern recognition receptors (PRRs) is a key component of plant innate immunity. The Arabidopsis PRR EF‐Tu receptor ...(EFR) recognizes the bacterial PAMP elongation factor Tu (EF‐Tu) and its derived peptide elf18. Previous work revealed that transgenic expression of AtEFR in Solanaceae confers elf18 responsiveness and broad‐spectrum bacterial disease resistance. In this study, we developed a set of bioassays to study the activation of PAMP‐triggered immunity (PTI) in wheat. We generated transgenic wheat (Triticum aestivum) plants expressing AtEFR driven by the constitutive rice actin promoter and tested their response to elf18. We show that transgenic expression of AtEFR in wheat confers recognition of elf18, as measured by the induction of immune marker genes and callose deposition. When challenged with the cereal bacterial pathogen Pseudomonas syringae pv. oryzae, transgenic EFR wheat lines had reduced lesion size and bacterial multiplication. These results demonstrate that AtEFR can be transferred successfully from dicot to monocot species, further revealing that immune signalling pathways are conserved across these distant phyla. As novel PRRs are identified, their transfer between plant families represents a useful strategy for enhancing resistance to pathogens in crops.
The metazoan innate immune system senses bacterial infections by detecting highly conserved bacterial molecules, termed pathogen‐associated molecular patterns (PAMPs). PAMPs are detected by a variety ...of host pattern recognition receptors (PRRs), whose function is to coordinate downstream immune responses. PRR activities are, in part, regulated by their subcellular localizations. Accordingly, professional phagocytes can detect extracellular bacteria and their PAMPs via plasma membrane‐oriented PRRs. Conversely, phagocytosed bacteria and their PAMPs are detected by transmembrane PRRs oriented toward the phagosomal lumen. Even though PAMPs are unable to passively diffuse across membranes, phagocytosed bacteria are also detected by PRRs localized within the host cell cytosol. This phenomenon is explained by phagocytosis of bacteria that specialize in phagosomal escape and cytosolic residence. Contrary to this cytosolic lifestyle, most bacteria studied to date spend their entire intracellular lifestyle contained within phagosomes, yet they also stimulate cytosolic PRRs. Herein, we will review our current understanding of how phagosomal PAMPs become accessible to cytosolic PRRs, as well as highlight knowledge gaps that should inspire future investigations.
The graphical illustrates the several means by which bacterial products may exit phagosomes to stimulate innate immune receptors present in the cytoplasm of eukaryotic cells. Each of these means of pathogen‐associated molecular pattern exodus is discussed in this review.
Background: Two novel systemic inflammation indices, SII and SIRI, are associated with increased risk of cardiovascular diseases (CVD). However, SII and SIRI are prone to change over time and the ...association between changeable status and long-term outcome risk remains to be uncovered. This study aims to examine the association between the dynamic status of SII and SIRI and risk of CVD. Methods: This prospective study included a total of 45,809 subjects without MI, stroke and cancer prior to or in 2010 (baseline of this study). The dynamic status of SII and SIRI during 2006, 2008, and 2010 was assessed by dynamic trajectories (primary exposure), annual increase, and average value. The outcome was CVD incidence during 8.6 years' follow-up. Multiple Cox regression models were used to calculate the adjusted hazard ratios (HRs) and confidence intervals (95% CIs). Results: Four dynamic trajectories of SII and SIRI were identified as follows: low stable pattern, moderate stable pattern, increase pattern, and decrease pattern. For SII, compared with "low stable pattern", after controlling confounders and level of SII in 2006, adjusted HRs were 1.24 (95% CI = 1.02-1.51) for "increase pattern" and 1.11 (95% CI = 1.00-1.23) for "moderate-stable pattern" while the association was not significant for "decrease pattern". Additionally, the highest group of annual SII increase and average SII had respective HR of 1.20 (95% CI = 1.05-1.37) and 1.32 (95% CI = 1.13-1.55). The results were consistent for SIRI. "Increase pattern" and "moderate stable pattern" increased the risk of CVD by 38% (HR = 1.38, 95% CI = 1.17-1.63) and 12% (HR = 1.12, 95% CI = 1.01-1.25), while no significant association was found for "decrease pattern". The highest group of annual SIRI increase and average SIRI had respective HR of 1.25 (95% CI = 1.09-1.44) and 1.39 (95% CI = 1.19-1.63). Conclusion: Dynamic status of SII and SIRI was significantly associated with risk of CVD, which highlighted that we should focus on the dynamic change of SII and SIRI. Keywords: systemic inflammation, dynamic status, prospective study, cardiovascular diseases
•The proposed descriptor is a new descriptor, exploring asymmetry of a facial image.•The proposed descriptor effectively encodes pixels eight bits only.•CSQP shows consistent improvements in ...recognition and retrieval frameworks.•The performance of the proposed descriptor is better in uncontrolled environment.
Facial features are defined as the local relationships that exist amongst the pixels of a facial image. Hand-crafted descriptors identify the relationships of the pixels in the local neighborhood defined by the kernel. Kernel is a two dimensional matrix which is moved across the facial image. Distinctive information captured by the kernel with limited number of pixel achieves satisfactory recognition and retrieval accuracies on facial images taken under constrained environment (controlled variations in light, pose, expressions, and background). To achieve similar accuracies under unconstrained environment local neighborhood has to be increased, in order to encode more pixels. Increasing local neighborhood also increases the feature length of the descriptor. In this paper we propose a hand-crafted descriptor namely Centre Symmetric Quadruple Pattern (CSQP), which is structurally symmetric and encodes the facial asymmetry in quadruple space. The proposed descriptor efficiently encodes larger neighborhood with optimal number of binary bits. It has been shown using average entropy, computed over feature images encoded with the proposed descriptor, that the CSQP captures more meaningful information as compared to state of the art descriptors. The retrieval and recognition accuracies of the proposed descriptor has been compared with state of the art hand-crafted descriptors (CSLBP, CSLTP, LDP, LBP, SLBP and LDGP) on bench mark databases namely; LFW, Color-FERET, and CASIA-face-v5. Result analysis shows that the proposed descriptor performs well under controlled as well as uncontrolled variations in pose, illumination, background and expressions.
The bacterial flagellin (FliC) epitopes flg22 and flgII-28 are microbe-associated molecular patterns (MAMPs). Although flg22 is recognized by many plant species via the pattern recognition receptor ...FLS2, neither the flgII-28 receptor nor the extent of flgII-28 recognition by different plant families is known.
Here, we tested the significance of flgII-28 as a MAMP and the importance of allelic diversity in flg22 and flgII-28 in plant–pathogen interactions using purified peptides and a Pseudomonas syringae ΔfliC mutant complemented with different fliC alleles.
The plant genotype and allelic diversity in flg22 and flgII-28 were found to significantly affect the plant immune response, but not bacterial motility. The recognition of flgII-28 is restricted to a number of solanaceous species. Although the flgII-28 peptide does not trigger any immune response in Arabidopsis, mutations in both flg22 and flgII-28 have FLS2-dependent effects on virulence. However, the expression of a tomato allele of FLS2 does not confer to Nicotiana benthamiana the ability to detect flgII-28, and tomato plants silenced for FLS2 are not altered in flgII-28 recognition.
Therefore, MAMP diversification is an effective pathogen virulence strategy, and flgII-28 appears to be perceived by an as yet unidentified receptor in the Solanaceae, although it has an FLS2-dependent virulence effect in Arabidopsis.
Pattern‐triggered immunity (PTI) is typically initiated in plants by recognition of pathogen‐ or damage‐associated molecular patterns (PAMP/DAMPs) by cell surface‐localized pattern recognition ...receptors (PRRs). Here, we investigated the role in PTI of Arabidopsis thaliana brassinosteroid‐signalling kinases 7 and 8 (BSK7 and BSK8), which are members of the receptor‐like cytoplasmic kinase subfamily XII. BSK7 and BSK8 localized to the plant cell periphery and interacted in yeast and in planta with FLS2, but not with other PRRs. Consistent with a role in FLS2 signalling, bsk7 and bsk8 single and bsk7,8 double mutant plants were impaired in several immune responses induced by flg22, but not by other PAMP/DAMPs. These included resistance to Pseudomonas syringae and Botrytis cinerea, reactive oxygen species accumulation, callose deposition at the cell wall, and expression of the defence‐related gene PR1, but not activation of MAP kinases and expression of the FRK1 and WRKY29 genes. bsk7, bsk8, and bsk7,8 plants also displayed enhanced susceptibility to P. syringae and B. cinerea. Finally, BSK7 and BSK8 variants mutated in their myristoylation site or in the ATP‐binding site failed to complement defective phenotypes of the corresponding mutants, suggesting that localization to the cell periphery and kinase activity are critical for BSK7 and BSK8 functions. Together, these findings demonstrate that BSK7 and BSK8 play a role in PTI initiated by recognition of flg22 by interacting with the FLS2 immune receptor.
Arabidopsis BSK7 and BSK8 are membrane‐localized receptor‐like cytoplasmic kinases regulating a subset of PAMP‐triggered immunity responses that counteract Pseudomonas syringae and Botrytis cinerea infection.
PDF
