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In the last 20 years, severe wheat stem rust outbreaks have been recorded in Africa, Europe, and Central Asia. This previously well controlled disease, caused by the fungus Puccinia graminis f. sp. tritici, has reemerged as a major threat to wheat cultivation. The stem rust (Sr) resistance gene Sr22 encodes a nucleotide-binding and leucine-rich repeat receptor which confers resistance to the highly virulent African stem rust isolate Ug99. Here, we show that the Sr22 gene is conserved among grasses in the Triticeae and Poeae lineages. Triticeae species contain syntenic loci with single-copy orthologs of Sr22 on chromosome 7, except Hordeum vulgare, which has experienced major expansions and rearrangements at the locus. We also describe 14 Sr22 sequence variants obtained from both Triticum boeoticum and the domesticated form of this species, T. monococcum, which have been postulated to encode both functional and nonfunctional Sr22 alleles. The nucleotide sequence analysis of these alleles identified historical sequence exchange resulting from recombination or gene conversion, including breakpoints within codons, which expanded the coding potential at these positions by introduction of nonsynonymous substitutions. Three Sr22 alleles were transformed into wheat cultivar Fielder and two postulated resistant alleles from Schomburgk (hexaploid wheat introgressed with T. boeoticum segment carrying Sr22) and T. monococcum accession PI190945, respectively, conferred resistance to P. graminis f. sp. tritici race TTKSK, thereby unequivocally confirming Sr22 effectiveness against Ug99. The third allele from accession PI573523, previously believed to confer susceptibility, was confirmed as nonfunctional against Australian P. graminis f. sp. tritici race 98-1,2,3,5,6.[Graphic: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Polysaccharide molecules chitooligosaccharides (COs) and peptidoglycan not only activate plant immunity but also trigger plant symbiosis signalling. Here the authors show that a combination of COs and lipochitooligosaccharides (LCOs) act synergistically to suppress immunity and promote symbiosis to facilitate beneficial fungal associations.

Abstract Background Effective disease management depends on timely and accurate diagnosis to guide control measures. The capacity to distinguish between individuals in a pathogen population with specific properties such as fungicide resistance, toxin production and virulence profiles is often essential to inform disease management approaches. The genomics revolution has led to technologies that can rapidly produce high-resolution genotypic information to define individual variants of a pathogen species. However, their application to complex fungal pathogens has remained limited due to the frequent inability to culture these pathogens in the absence of their host and their large genome sizes. Results Here, we describe the development of Mobile And Real-time PLant disEase (MARPLE) diagnostics, a portable, genomics-based, point-of-care approach specifically tailored to identify individual strains of complex fungal plant pathogens. We used targeted sequencing to overcome limitations associated with the size of fungal genomes and their often obligately biotrophic nature. Focusing on the wheat yellow rust pathogen, Puccinia striiformis f.sp. tritici (Pst), we demonstrate that our approach can be used to rapidly define individual strains, assign strains to distinct genetic lineages that have been shown to correlate tightly with their virulence profiles and monitor genes of importance. Conclusions MARPLE diagnostics enables rapid identification of individual pathogen strains and has the potential to monitor those with specific properties such as fungicide resistance directly from field-collected infected plant tissue in situ. Generating results within 48 h of field sampling, this new strategy has far-reaching implications for tracking plant health threats.

Wheat stem rust caused by the fungus Puccinia graminis f. sp. tritici (Pgt), is regaining prominence due to the recent emergence of virulent isolates and epidemics in Africa, Europe and Central Asia. The development and deployment of wheat cultivars with multiple stem rust resistance (Sr) genes stacked together will provide durable resistance. However, certain disease resistance genes can suppress each other or fail in particular genetic backgrounds. Therefore, the function of each Sr gene must be confirmed after incorporation into an Sr-gene stack. This is difficult when using pathogen disease assays due to epistasis from recognition of multiple avirulence (Avr) effectors. Heterologous delivery of single Avr effectors can circumvent this limitation, but this strategy is currently limited by the paucity of cloned Pgt Avrs. To accelerate Avr gene cloning, we outline a procedure to develop a mutant population of Pgt spores and select for gain-of-virulence mutants. We used ethyl methanesulphonate (EMS) to mutagenize urediniospores and create a library of > 10,000 independent mutant isolates that were combined into 16 bulks of ~658 pustules each. We sequenced random mutants and determined the average mutation density to be 1 single nucleotide variant (SNV) per 258 kb. From this, we calculated that a minimum of three independently derived gain-of-virulence mutants is required to identify a given Avr gene. We inoculated the mutant library onto plants containing Sr43, Sr44, or Sr45 and obtained 9, 4, and 14 mutants with virulence toward Sr43, Sr44, or Sr45, respectively. However, only mutants identified on Sr43 and Sr45 maintained their virulence when reinolculated onto the lines from which they were identified. We further characterized 8 mutants with virulence toward Sr43. These also maintained their virulence profile on the stem rust international differential set containing 20 Sr genes, indicating that they were most likely not accidental contaminants. In conclusion, our method allows selecting for virulent mutants toward targeted resistance (R) genes. The development of a mutant library from as little as 320 mg spores creates a resource that enables screening against several R genes without the need for multiple rounds of spore multiplication and mutagenesis.

Pneumococcal conjugate vaccines have decreased the rates of invasive pneumococcal disease (IPD) in children. Since vaccine introduction, however, rates of infection due to nonvaccine Streptococcus pneumoniae serotypes have increased. We now describe 3 meningitis cases due to the nonvaccine serotypes 35B and 11A from rural United States.

Human immunodeficiency virus (HIV)-infected individuals display an enhanced production of reactive oxygen species (ROS). This reduction of antioxidant capacity in host tissues has been related to the decrease in total levels of ROS scavengers such as glutathione (GSH). Prevention of opportunistic infections due to a weakened immune system is becoming a key strategy along with HIV elimination. Research in these directions is clearly warranted, especially a combination of antiretrovirals and antioxidants to ameliorate oxidative stress, improve intracellular uptake and target viral reservoirs. Hence, we aimed to formulate liposomes loaded with the antiretroviral drug efavirenz (EFA) in the presence of glutathione, as these carriers can be engineered to enhance the ability to reach the target reservoirs. The goal of the present work was to investigate the intracellular uptake of EFA-loaded liposome (with and without GSH) by human monocytic leukemia cells (THP-1 cells) and examine cell viability and ROS scavenging activity. Results obtained provided significant data as follows: (i) treatment with EFA and GSH combination could enhance the uptake and reduce cytotoxicity; (ii) encapsulation of EFA into liposomes increased its levels in the macrophages, which was further enhanced in the presence of GSH; (iii) delivery of EFA in the presence of GSH quenched the intracellular ROS, which was significantly higher when delivered via liposomes. Data revealed that a combination of EFA and GSH encompasses advantages; hence, GSH supplementation could be a safe and cost-effective treatment to slow the development of HIV infection and produce an immune-enhancing effect.

Drug discovery and development has become longer and costlier process. The fear of failure and stringent regulatory review process is driving pharmaceutical companies towards “me too” drugs and improved generics (505(b) (2)) fillings. The discontinuance of molecules at late stage clinical trials is common these years. The molecules are withdrawn at various stages of discovery and development process for reasons such as poor ADME properties, lack of efficacy and safety reasons. Hence this review focuses on possible applications of formulation and drug delivery to salvage molecules and improve the drugability. The formulation and drug delivery technologies are suitable for addressing various issues contributing to attrition are discussed in detail.

Classical interferon-α has been shown to be associated with the development of a variety of autoimmune disorders. A 34-year-old white woman with chronic hepatitis C virus infection who was treated with pegylated interferon α-2a and ribavirin, developed Grave′s disease and autoimmune hepatitis (AIH) at 32 and 44 weeks, respectively, following initiation of the therapy. The diagnosis of AIH was made based on the new development of anti-smooth muscle antibodies, anti-mitochondrial antibodies, and liver biopsy findings. It was confirmed by positive response to steroid challenge and was assessed according to the international AIH scoring system. Based on the previous case reports, we review the existing literature. Clinicians should be aware of the possibility of multiple autoimmune disorders during interferon-based therapy for chronic hepatitis.

Haemangiomas are benign proliferative tumours with vascular tissue origin. These neoplasms are recognised as benign tumours commonly found in infancy, characterised by a period of rapid growth accompanied by proliferation of endothelial cells, followed by gradual involution. The male to female ratio is observed to be 3:1, with a predominant impact on the female population, particularly during the early stages of their second decade of life. The diameter of the lesion spans from a few millimeters to several centimeters, with rare instances exceeding 2.5 cm. The present case report details the occurrence of Lobular Capillary Haemangioma (LCH) in a young male patient of six years, who exhibited gingival overgrowth in the anterior maxillary region. The patient presented with symptoms of discomfort during mastication, occlusal interference, and excessive hemorrhage during oral hygiene practices. Due to the lesion’s extensive blood supply and the confirmation of the diagnosis in the histology report, it was surgically removed in a single session while the patient was under conscious anaesthesia. The patient underwent a thorough six-month follow-up examination, which demonstrated a favourable outcome with no evidence of lesion recurrence. Although haemangiomas are prevalent soft tissue tumours in the head and neck region, they are infrequently found in the oral cavity and rarely encountered by doctors. Intraoral haemangiomas most commonly occur in the lips, tongue, buccal mucosa, and palate. However, this case report describes a rare occurrence in the maxillary anterior site, which has limited documentation. The treatment involved the use of monopolar cautery, which effectively reduced bleeding at the surgical site after the use of a scalpel. The purpose of present case report is to report an unusual case of a benign tumour occurring in the anterior maxillary region, which was diagnosed as LCH.

Abstract The NaZn13 type itinerant magnet LaFe13−xSix has seen considerable interest due to its unique combination of large magnetocaloric effect and low hysteresis. Here, this alloy with a combination of magnetometry, bespoke microcalorimetry, and inelastic neutron scattering is investigated. Inelastic neutron scattering reveals the presence of broad quasielastic scattering that persists across the magnetic transition, which is attributed to spin fluctuations. In addition, a quasielastic peak is observed at Q = 0.52 Å−1 for x = 1.2 that exists only in the paramagnetic state in proximity to the itinerant metamagnetic transition and argue that this indicates emergence of a hidden mag the netic phase that drives the first‐order phase transition in this system.

This paper proposes a novel approach for modeling noise-induced annoyance using the fuzzy technique. The fuzzy approach offers a convenient way of representing the relationships between the inputs and outputs of a system in the form of simple IF-THEN rules. Annoyance, in the present model, is considered as a function of noise level, its duration of occurrence, and the socioeconomic status of a person. The model has been implemented on the Fuzzy Logic Toolbox of MATLAB, using both Mamdani and Sugeno techniques. The results of the model are applicable to the urban areas of India. Index Terms--Annoyance, fuzzy modeling, fuzzy systems, noise pollution.