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High Plains wheat mosaic virus (genus Emaravirus), an octapartite negative-sense RNA virus, encodes two RNA silencing suppressors, P7 and P8. In this study, we found that P7 and P8 efficiently delayed the onset of dsRNA-induced transitive pathway of RNA silencing. Electrophoretic mobility shift assays (EMSA) revealed that only P7 protected long dsRNAs from dicing in vitro and bound weakly to 21- and 24-nt PTGS-like ds-siRNAs. In contrast, P8 bound strongly and relatively weakly to 21- and 24-nt ds-siRNAs, respectively, suggesting size-specific binding. In EMSA, neither protein bound to 180-nt and 21-nt ssRNAs at detectable levels. Sequence analysis revealed that P7 contains a conserved GW motif. Mutational disruption of this motif resulted in loss of suppression of RNA silencing and pathogenicity enhancement, and failure to complement the silencing suppression-deficient wheat streak mosaic virus. Collectively, these data suggest that P7 and P8 proteins utilize distinct mechanisms to overcome host RNA silencing for successful establishment of systemic infection in planta.

Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TriMV), distinct members in the family Potyviridae, are economically important wheat-infecting viruses in the Great Plains region. Previously, we reported that coinfection of wheat by WSMV and TriMV caused disease synergism with increased concentration of both viruses. The mechanisms of synergistic interaction between WSMV and TriMV and the effects of prior infection of wheat by either of these “synergistically interacting partner” (SIP) viruses on the establishment of local and systemic infection by the other SIP virus are not known. In this study, using fluorescent protein-tagged viruses, we found that prior infection of wheat by WSMV or TriMV negatively affected the onset and size of local foci elicited by subsequent SIP virus infection compared with those in buffer-inoculated wheat. These data revealed that prior infection of wheat by an SIP virus has no measurable advantage for another SIP virus on the initiation of infection and cell-to-cell movement. In TriMV-infected wheat, WSMV exhibited accelerated long-distance movement and increased accumulation of genomic RNAs compared with those in buffer-inoculated wheat, indicating that TriMV-encoded proteins complemented WSMV for efficient systemic infection. In contrast, TriMV displayed delayed systemic infection in WSMV-infected wheat, with fewer genomic RNA copies in early stages of infection compared with those in buffer-inoculated wheat. However, during late stages of infection, TriMV accumulation in WSMV-infected wheat increased rapidly with accelerated long-distance movement compared with those in buffer-inoculated wheat. Taken together, these data suggest that interactions between synergistically interacting WSMV and TriMV are asymmetrical; thus, successful establishment of synergistic interaction between unrelated viruses will depend on the order of infection of plants by SIP viruses.

High Plains wheat mosaic virus (HPWMoV, genus Emaravirus; family Fimoviridae), transmitted by the wheat curl mite (Aceria tosichella Keifer), harbors a monocistronic octapartite single-stranded negative-sense RNA genome. In this study, putative proteins encoded by HPWMoV genomic RNAs 2–8 were screened for potential RNA silencing suppression activity by using a green fluorescent protein-based reporter agroinfiltration assay. We found that proteins encoded by RNAs 7 (P7) and 8 (P8) suppressed silencing induced by single- or double-stranded RNAs and efficiently suppressed the transitive pathway of RNA silencing. Additionally, a Wheat streak mosaic virus (WSMV, genus Tritimovirus; family Potyviridae) mutant lacking the suppressor of RNA silencing (ΔP1) but having either P7 or P8 from HPWMoV restored cell-to-cell and long-distance movement in wheat, thus indicating that P7 or P8 rescued silencing suppressor-deficient WSMV. Furthermore, HPWMoV P7 and P8 substantially enhanced the pathogenicity of Potato virus X in Nicotiana benthamiana. Collectively, these data demonstrate that the octapartite genome of HPWMoV encodes two suppressors of RNA silencing.

Wheat streak mosaic virus (WSMV, genus Tritimovirus, family Potyviridae) is an economically important virus infecting wheat in the Great Plains region of the USA. Previously, we reported that the P1 protein of WSMV acts as a viral suppressor of RNA silencing. In this study, we delineated the minimal region of WSMV P1 and examined its mechanisms in suppression of RNA silencing. We found that the 25 N-terminal amino acids are dispensable, while deletion of a single amino acid at the C-terminal region completely abolished the RNA silencing suppression activity of P1. Electrophoretic mobility shift assays with in vitro expressed P1 revealed that the P1 protein formed complexes with green fluorescent protein-derived 180-nt dsRNA and 21 and 24-nt ds-siRNAs, and WSMV coat protein-specific 600-nt dsRNA. These data suggest that the P1 protein of WSMV binds to dsRNAs in a size- and sequence-independent manner. Additionally, in vitro dicing assay with human Dicer revealed that the P1 protein efficiently protects dsRNAs from processing by Dicer into siRNAs, by forming complexes with dsRNA. Sequence comparison of P1-like proteins from select potyvirid species revealed that WSMV P1 harbors a glycine-tryptophan (GW) motif at the C-terminal region. Disruption of GW motif in WSMV P1 through W303A mutation resulted in loss of silencing suppression function and pathogenicity enhancement, and abolished WSMV viability. These data suggest that the mechanisms of suppression of RNA silencing of P1 proteins of potyvirid species appear to be broadly conserved in the family Potyviridae.

Wheat streak mosaic virus (WSMV; genus Tritimovirus; family Potyviridae) is an economically important wheat virus that is transmitted by the wheat curl mite (WCM; Aceria tosichella Keifer) in a persistent manner. Virus–vector coevolution may potentially influence vector gene expression to prolong viral association and thus increase virus transmission efficiency and spread. To understand the transcriptomic responses of WCM to WSMV, RNA sequencing was performed to assemble and analyse transcriptomes of WSMV viruliferous and aviruliferous mites. Among 7291 de novo-assembled unigenes, 1020 were differentially expressed between viruliferous and aviruliferous WCMs using edgeR at a false discovery rate ≤0.05. Differentially expressed unigenes were enriched for 108 gene ontology terms, with the majority of the unigenes showing downregulation in viruliferous mites in comparison to only a few unigenes that were upregulated. Protein family and metabolic pathway enrichment analyses revealed that most downregulated unigenes encoded enzymes and proteins linked to stress response, immunity and development. Mechanistically, these predicted changes in mite physiology induced by viral association could be suggestive of pathways needed for promoting virus–vector interactions. Overall, our data suggest that transcriptional changes in viruliferous mites facilitate prolonged viral association and alter WCM development to expedite population expansion, both of which could enhance viral transmission.

Summary Chronic rhinosinusitis (CRS) is one of the most common reasons that persons seek medical care. 1 CRS may originate from or be perpetuated by local or systemic factors predisposing to sinus ostial obstruction and infection. These factors include anatomic or inflammatory factors leading to sinus ostial narrowing, disturbances in mucociliary transport, and subsequent infection. CRS is diagnosed by various symptoms (lasting for at least 12 weeks), which include long-term nasal congestion, thick mucus production, loss of sense of smell, sinus pressure, and facial pain, as well as physical and radiographic evidence of mucosal swelling. The goal of medical management is to reduce the swelling and inflammation, especially of the ostia, and promote drainage and a more normal nasal environment. The medical treatment should include empiric broad-spectrum antibiotics with adjunctive therapy, including nasal and oral steroids, decongestants, expectorants, and saline nasal irrigation. If symptoms improve after four weeks of treatment initiation, it is recommended that the nasal steroid sprays and nasal saline irrigations should continue for at least three months. If symptoms do not improve and there is still presence of CRS signs and symptoms, the patient should be referred to an appropriate specialist for further management.

Objective The objective of this study was to determine whether differences in urinary proinflammatory cytokines, interleukin-1beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-alpha), exist between migraineurs and nonheadache control subjects, and between nonhormonal migraine and menstrual migraine. Any differences noted would expand and clarify a neuroimmune hypothesis of migraine pathogenesis and lead to future diagnostic markers or therapeutic options or both for the disorder. Background Current theories of migraine pathogenesis focus on biochemical abnormalities in the central nervous system resulting in sterile inflammation of meningeal blood vessels. Vasoactive substances involved in this process may include substance P, calcitonin gene-related peptide, neurokinin A, serotonin, and nitric oxide. Immune cell products, such as histamine, leukotrienes, and cytokines, also have vascular inflammatory properties. Methods A study of proinflammatory cytokines, IL-1beta, IL-6, and TNF-alpha, was undertaken in menstrual migraineurs. During and outside of menses, 24-hour urine samples of 19 women with migraine were taken during a menstrual migraine, a nonmenstrual migraine, and a headache-free day, and compared with 24-hour urine samples taken of 10 nonheadache controls during and outside of menses. Results A neuroimmune mechanism for migraine was tested with expected increases in proinflammatory cytokines tested during a migraine. This hypothesis was not validated. Mean IL-6 levels were increased in all three samples of migraineurs versus controls, but did not achieve statistical significance. No differences were found in IL-1beta levels between samples. Interestingly, marked differences were found in TNF-alpha values in menstrual migraineurs. Twelve (63%) of 19 migraineurs had at least one urine sample with undetectable TNF-alpha levels, whereas none of the 20 samples given by the 10 nonheadache controls in this study had undetectable levels. Thirty-two samples from men with cluster headache and nonheadache control subjects in prior studies had detectable levels. Conclusions This deficiency of TNF-alpha levels in women with migraine may signal a disordered neuroimmune communication network and predisposition to migraine.

Many studies have documented the significant psychological impact of severe psoriasis. Although studies have illustrated the association of psoriasis with psychiatric conditions, including depression and anxiety, this is the first to report new onset suicidal ideations presenting concomitantly with an erythrodermic eruption of psoriasis. This novel finding highlights the need for evaluation of mental status in patients presenting with erythroderma associated with any dermatologic condition, as such an increase in dermatological severity is correlated with suicidal ideations. This case illustrates the importance of screening for depression in the management of psoriasis and specifically underscores the association of severity of disease with suicidal ideations.

Localization in wireless network refers to determining the location of a mobile user which may either be stationary or in motion. This paper presents the design and evaluation of an algorithm for localization of mobile nodes in GSM networks. The proposed algorithm does not use GPS and has the advantages of being cost effective and reliable. The received signal strength from the base stations in the proximity of the mobile form the basis for the proposed algorithm. The algorithm concentrates on improving the accuracy of estimated location of the mobile by using a prediction-interpolation technique. The key aspects of the proposed localization technique are that it assumes linear dependency between the accuracy of the estimated mobile location and the received signal strengths from the neighboring base stations, and tunes the location estimate based on this mapping.

There are no uniform protocols in the United States for safe, environmentally acceptable disposal of controlled substances by patients. In addition, there are conflicting protocols used by various institutions for the disposal of narcotic medications. Although the US Drug Enforcement Administration oversees the prescribing, acquisition, and distribution of controlled substances and works to prevent the illegal diversion of these products, it stops short of recommending specific mechanisms for consumers to dispose of unused medications. The lack of specific regulations in this area increases the risk of illegal diversion of prescription medications and other controlled substances. The authors review and examine the dilemma posed by an ill-defined set of guidelines for disposal of controlled substances by patients and institutions not registered with the US Drug Enforcement Administration. The authors encourage public officials to update and reform ambiguous policies regarding opioid disposal by consumers and allied healthcare workers.