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The severe yellowing disease (amarelao) on melon plants is a serious problem in Brazil, although the causative agent remained unknown for a long time. Recently, recombinant isolates of cucurbit aphid‐borne yellows virus (CABYV) were reported as the possible causative agents of this disease on melon plants. Although aphids are known to be the vectors of the common type of CABYV isolates, almost no aphid colony was observed in the major melon fields in Brazil with high incidence of the severe yellowing disease. In contrast, whiteflies are often abundant. Based on this observation, the hypothesis of the transmission of recombinant CABYV by whiteflies was evaluated. After thorough transmission experiments, we found that this recombinant CABYV isolate was transmitted by the whitefly Bemisia tabaci MEAM1, but not by Aphis gossipii. Furthermore, the host response by whitefly‐based inoculation in cucurbits and other indicator plants showed differences in host range when compared to the common type of CABYV. Due to its transmissibility by the whitefly and the distant relationship of the P3/P5 protein to CABYV, the name “cucurbit whitefly‐borne yellows virus” is proposed for this recombinant CABYV. This is the second report of polerovirus transmission by the whitefly B. tabaci, following the report of pepper whitefly‐borne vein yellows virus.

Scope: It has been proposed that endogenously form N‐nitroso compounds (NOCs) are partly responsible for the link between red meat consumption and colorectal cancer (CRC) risk. As nitrite has been indicated as critical factor in the formation of NOCs, the impact of replacing the additive sodium nitrite (E250) by botanical extracts in the PHYTOME project is evaluated. Method and Results: A human dietary intervention study is conducted in which healthy subjects consume 300 g of meat for 2 weeks, in subsequent order: conventional processed red meat, white meat, and processed red meat with standard or reduced levels of nitrite and added phytochemicals. Consumption of red meat products enriched with phytochemicals leads to a significant reduction in the faecal excretion of NOCs, as compared to traditionally processed red meat products. Gene expression changes identify cell proliferation as main affects molecular mechanism. High nitrate levels in drinking water in combination with processed red meat intake further stimulates NOC formation, an effect that could be mitigated by replacement of E250 by natural plant extracts. Conclusion: These findings suggest that addition of natural extracts to conventionally processed red meat products may help to reduce CRC risk, which is mechanistically support by gene expression analyses.

This study investigated the peripheral frequency of monocytes, CD4 + T cell subsets and the systemic levels of cytokines in lean and obese men with different levels of cardiorespiratory fitness (CRF). Mononuclear cells were obtained from 45 lean and 45 obese men who were assigned into six groups according to their body mass index and CRF (low, moderate, or high VO2Peak ) to analyze the frequency of monocyte subsets and subpopulations of CD4 + T cells (Treg cells, CD4 + CD25high CD127low ; mTeff, CD4 + CD25-CD39+; mTreg, CD4 + CD25+CD39+). The systemic levels of interleukin (IL)-6, IL-10, IL-17a, IL-33, leptin, and tumor necrosis factor-alpha (TNF-α) were also evaluated. Seven sedentary obese men performed one week of high-intensity interval training (HIIT, 3 sessions/week), and blood samples were collected before and 24 hours after the last session for phenotypic analysis of T cells and monocytes. Obese individuals presented an inflammatory profile characterized by lower frequencies of Treg and mTreg cells and higher proportions of proinflammatory monocytes. However, higher CRF status increased the frequencies of Treg cells and mTreg cells and decreased the percentage of CD4 + mTeff cells and intermediate and non-classical monocytes in the peripheral blood from lean and obese men. Systemic lower levels of proinflammatory (IL-6 and TNF-) cytokines and higher concentrations of IL-10 and IL-33 were observed in moderate and higher CRF in all subjects. HIIT increased the proportions of circulating mTreg and Treg cells in sedentary obese individuals. The immunoregulatory role of CRF contributes to the maintenance of low levels of inflammatory mediators.

Introduction Typically, humans place themselves at a preferred distance from others. This distance is known to characterize human spatial behavior. Here, we focused on neurocognitive conditions that may affect interpersonal distances. The current study investigated whether neurocognitive deficiencies in numerical and spatial knowledge may affect social perception and modulate personal space. Method In an event‐related potential (ERP) study, university students with developmental dyscalculia (DD) and typically developing control participants were given a computerized version of the comfortable interpersonal distance task, in which participants were instructed to press the spacebar when they began to feel uncomfortable by the approach of a virtual protagonist. Results Results showed that students with deficiencies in numerical and spatial skills (i.e., DD) demonstrated reduced variability in their preferred distance from an approaching friend. Importantly, DD showed decreased amplitude of the N1 wave in the friend condition. Conclusion These results suggest that people coping with deficiencies in spatial cognition have a less efficient allocation of spatial attention in the service of processing personal distances. Accordingly, the study highlights the fundamental role of spatial neurocognition in organizing social space., We found that even this seemingly resilient group of young adults with dyscalculia who are enrolled in university display abnormal neuro‐physiological functioning suggestive of a less efficient allocation of spatial attention in the service of processing distances in everyday activities. This deficient attention mechanism leads to abnormal choices of preferred distance from others, mainly from friends, which may have an effect on reciprocal social behavior.

Although individuals with autism spectrum disorder (ASD) have impaired responses to interpersonal touch, the underlying neural correlates remain largely unknown. Here, we examined the neural correlates that underlie interpersonal touch perception in individuals with either high or low autistic traits. Fifty-three participants were classified as having either high or low autistic traits based on their performance on the autism quotient (AQ) questionnaire. We hypothesized that individuals with high AQ scores would have relatively high touch hypervigilance, reflected as earlier P1 and stronger late positive potential (LPP) responses, two components of event-related potentials that serve as electrophysiological markers of anxiety bias. We recorded each participant's electroencephalography activity during presentation of images depicting human touch, object touch, and non-touch control images. Consistent with our hypothesis, AQ scores were positively correlated with social touch aversion. Moreover, participants with high AQ scores had earlier P1 and stronger LPP responses when presented with human touch compared to the control images. Importantly, a regression model revealed that earlier P1 and larger LPP amplitude measured during social touch observation can accurately predict higher autistic trait levels. Taken together, these findings indicate that individuals with high levels of autistic traits may have a hypervigilant response to observed social touch. Autism Res 2017, 0: 000-000. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2017, 10: 1141-1154. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Aim To evaluate the cytotoxicity and the mechanism of cell aggression of peracetic acid (PA) in comparison with sodium hypochlorite (NaOCl). Methodology L929 fibroblasts were exposed to 1% PA and 2.5% NaOCl, in different dilutions for 10 minutes. The following parameters were evaluated: cell metabolism by methylthiazol tetrazolium assay (MTT), external morphology by scanning electron microscopy, ultrastructure by transmission electron microscopy, the cytoskeleton by means of actin and α-tubulin labeling, and the type of cell death by flow cytometry (apoptosis/necrosis). The data were analyzed by two-way ANOVA and the Bonferroni post-test (α=0.05). Results The PA group had lower cell viability and a higher percentage of necrotic cells than the NaOCl group (P < 0.05). Both solutions diminished cell metabolism, led to destructuring of the cytoskeleton, created changes in the external morphology, resulted in the accumulation of proteins in the rough endoplasmic reticulum, and induced cell death predominantly by necrosis. However, these changes were observed in lower doses of PA when compared with NaOCl. Conclusions Although they had the same mechanism of cytotoxicity, 1% PA had greater cytotoxic potential than 2.5% NaOCl. This article is protected by copyright. All rights reserved

Background and objective The prevalence of asthma has increased in communities that adopt a Western lifestyle and become more urbanized. Probiotics may be effective in the prevention of allergic diseases, such as asthma. The aim of the current study was to examine the effects of Saccharomyces cerevisiae UFMG A-905 in an allergic model of asthma. Methods Balb/c mice were sensitized twice with ovalbumin (OVA) intraperitoneally, 1 week apart and challenged with OVA intranasally for 3 days. Mice were daily treated with S. cerevisiae UFMG A-905 via gavaging needle 10 days before OVA sensitization and during challenges. After challenge, in vivo lung function was measured, and bronchoalveolar lavage (BAL) and lung inflammation were assessed. Results Oral treatment with S. cerevisiae UFMG A-905 significantly decreased airway hyperresponsiveness, total cell number and the influx of eosinophils to the airway, inflammatory cell in the lung, mucus expression in epithelial cells and the levels of IL-4, IL-5 and IL-13. Additionally, S. cerevisiae UFMG A-905 restored the levels of IL-10 and interferon (IFN)-gamma, and increased the levels of IL-17A. Conclusion Oral administration of S. cerevisiae UFMG A-905 prevented the development of major asthma-like characteristics in a mouse model.

Quantitative alterations in mast cell numbers in pancreatic lymph nodes (PLNs) have been reported to be associated with type 1 diabetes (T1D) progression, but their potential role during T1D remains unclear. In this study, we evaluated the role of mast cells in T1D induced by multiple low-dose streptozotocin (MLD-STZ) treatments, using two strains of mast cell-deficient mice (W/W(v) or Wsh/Wsh) and the adoptive transfer of mast cells. Mast cell deficient mice developed severe insulitis and accelerated hyperglycemia, with 100% of mice becoming diabetic compared to their littermates. In parallel, these diabetic mice had decreased numbers of T regulatory (Treg) cells in the PLNs. Additionally, mast cell deficiency caused a significant reduction in IL-10, TGF-β, and IL-6 expression in the pancreatic tissue. Interestingly, IL-6-deficient mice are more susceptible to T1D associated with reduced Treg-cell numbers in the PLNs, but mast cell transfer from wild-type mice induced protection to T1D in these mice. Finally, mast cell adoptive transfer prior to MLD-STZ administration conferred resistance to T1D, promoted increased Treg cells, and decreased IL-17-producing T cells in the PLNs. Taken together, our results indicate that mast cells are implicated in resistance to STZ-induced T1D via an immunological tolerance mechanism mediated by Treg cells.

Empathic accuracy refers to the ability of perceivers to accurately share the emotions of protagonists. Using a novel task assessing embarrassment, the current study sought to compare levels of empathic embarrassment accuracy among individuals with autism spectrum disorders (ASD) with those of matched controls. To assess empathic embarrassment accuracy, we compared the level of embarrassment experienced by protagonists to the embarrassment felt by participants while watching the protagonists. The results show that while the embarrassment ratings of participants and protagonists were highly matched among controls, individuals with ASD failed to exhibit this matching effect. Furthermore, individuals with ASD rated their embarrassment higher than controls when viewing themselves and protagonists on film, but not while performing the task itself. These findings suggest that individuals with ASD tend to have higher ratings of empathic embarrassment, perhaps due to difficulties in emotion regulation that may account for their impaired empathic accuracy and aberrant social behavior.

Background We have shown that mycobacterial antigens and CpG oligodeoxynucleotides downmodulate airway allergic inflammation by mechanisms dependent on T-cell activation. Here, we investigated the participation of the innate response, particularly the role of MyD88 adaptor, and Fas molecules in the effectiveness of DNA-HSP65 or CpG/culture filtrated proteins (CFP) immunotherapy. Methods Mice sensitized and challenged with Der p 1 allergen were treated with DNA-HSP65, CpG/CFP, or with adoptively transferred cells from immunized mice. The treatment efficacy was assessed by evaluating eosinophil recruitment, antibody, and cytokine production. Results In addition to downregulating the Th2 response, DNA-HSP65 and CpG/CFP promoted IL-10 and IFN-γ production. Adoptive transfer of cells from mice immunized with DNA-HSP65 or CpG/CFP to allergic recipients downmodulated the allergic response. Notably, transfer of cells from DNA-HSP65- or CpG/CFP-immunized MyD88−/− mice failed to reduce allergy. Additionally, for effective reduction of allergy by cells from CpG/CFP-immunized mice, Fas molecules were required. Although DNA-HSP65 or CpG/CFP immunization stimulated antigen-specific production of IFN-γ and IL-10, the effect of DNA-HSP65 was associated with IL-10 while CpG/CFP was associated with IFN-γ. Moreover, after stimulation with mycobacterial antigens plus Der p 1 allergen, cells from mite-allergic patients with asthma exhibited similar patterns of cytokine production as those found in the lung of treated mice. Conclusions This study provides new insights on the mechanisms of allergen-free immunotherapy by showing that both DNA-HSP65 and CpG/CFP downregulated house dust mite-induced allergic airway inflammation via distinct pathways that involve not only induction of mycobacterial-specific adaptive responses but also signaling via MyD88 and Fas molecules.

Tomato, one of the most important crops cultivated worldwide, has been severely affected by begomoviruses such as the Tomato chlorotic mottle virus (ToCMoV). Virulence factor AC2 is considered crucial for a successful virus-plant interaction and is known to act as a transcriptional activator and in some begomoviruses to function as an RNA silencing suppressor factor. However, the exact functions of the AC2 protein of the begomovirus ToCMoV are not yet established. The aim of the present study was to identify differentially expressed proteins of the model plant Nicotiana benthamiana in response to the expression of the AC2 gene, isolated from ToCMoV. N. benthamiana plants were inoculated with Agrobacterium tumefaciens containing the viral vector Potato virus X (PVX) and with the PVX-AC2 construction. 2DE was performed and proteins were identified by MS. The results showed that the expression of ToCMoV AC2 alters the levels of several host proteins, which are important for normal plant development, causing an imbalance in cellular homeostasis. This study highlights the effect of AC2 in the modulation of plant defense processes by increasing the expression of several oxidative stress-related and pathogenesis-related proteins, as well as its role in modulating the proteome of the photosynthesis and energy production systems.

An N-heterocyclic carbene gold complex IPr**AuNTf2 has been synthesized, spectroscopically investigated, structurally characterized, and used as a highly active and stable catalyst in the Hashmi phenol synthesis (IPr**=1,3-di-p-tolylimidazol-2-ylidene with four di-tert-butylbenzhydryl ortho substituents, Tf=trifluoromethansulfonyl). A side reaction comprises an irreversible arene oxide ring opening with subsequent 1,2 methyl shift. The advantage of the steric demand of the ancillary ligand was explained by higher equilibrium concentrations of the cationic gold species, the circumvention of inactive dinuclear intermediates, and the inhibition of catalyst decomposition pathways. The methanol addition–hydration of alkynes featured a turnover-limiting proton transfer step of an alkenylgold catalyst resting state, indicated by a large primary kinetic isotope effect and an alkyne competition experiment.

The silver chloride and gold chloride complex of the extremely sterically shielding N-heterocyclic carbene ligand IPr** have been synthesized and characterized. Formally, eight methyl groups of IPr have been replaced by 4-tert-butylphenyl substituents, and two para-methyl groups have been added. The world record for the ligand's buried volume (55.4 % for IPr**AuCl, and 56.7 % for IPr**AgCl) has been determined by single-crystal X-ray analyses. Reaction of IPr**AuCl with AgSbF6 in toluene yields AgCl and a cationic gold complex with toluene coordination. The same reaction in 1,2-dichloroethane leads to precipitation of AgCl and an equilibrium of [IPr**Au]SbF6 and [IPr**AuClAg]SbF6. Single crystals of the latter were suitable for an X-ray structure analysis, which reveal an Au–Cl–Ag triangle with an almost undisturbed IPr**–Au–Cl fragment and the coordination of two IPr** arenes to a silver cation. The structural parameters emphasize the role of NHC-Au cations as highly electrophilic “soft protons”.

Summary Background Previous studies have established that mycobacterial infections ameliorate allergic inflammation. However, a non-infectious approach that controls allergic responses might represent a safer and more promising strategy. The 60–65 kDa heat shock protein (Hsp) family is endowed with anti-inflammatory properties, but it is still unclear whether and how single mycobacterial Hsp control allergic disorders. Objective Therefore, in this study we determined whether the administration of Mycobacterial leprae Hsp65 expressed by recombinant a DNA plasmid could attenuate a previously established allergic response. Methods We used an experimental model of airway allergic inflammation to test the effects of immunotherapy with DNA encoding Hsp65. Allergic mice, previously sensitized and challenged with ovalbumin, were treated with tree intramuscular doses of recombinant DNA encoding Hsp65. After treatment, mice received a second allergen challenge and the allergic response was measured. Results We found that immunotherapy attenuated eosinophilia, pulmonary inflammation, Th2 cytokine and mucus production. Moreover, we showed that the inhibition of allergic response is dependent on IL-10 production. Both Hsp65 and allergen-specific IL-10-producing cells contributed to this effect. Cells transferred from DNA-immunized mice to allergic mice migrated to allergic sites and down-modulated the Th2 response. Conclusions and Clinical Relevance Our findings clearly show that immunotherapy with DNA encoding Hsp65 can attenuate an established Th2 allergic inflammation through an IL-10-dependent mechanism; moreover, the migration of allergen- and Hsp65-specific cells to the allergic sites exerts a fundamental role. This work represents a novel contribution to the understanding of immune regulation by Hsp65 in allergic diseases.

Epidemiological and experimental evidence supports the notion that microbial infections that are known to induce Th1-type immune responses can suppress Th2 immune responses, which are characteristics of allergic disorders. However, live microbial immunization might not be feasible for human immunotherapy. Here, we evaluated whether induction of Th1 immunity by the immunostimulatory sequences of CpG-oligodeoxynucleotides (CpG-ODN), with or without culture filtrate proteins (CFP), from Mycobacterium tuberculosis would suppress ongoing allergic lung disease. Presensitized and ovalbumin (OVA)-challenged mice were treated subcutaneously with CpG, or CpG in combination with CFP (CpG/CFP). After 15 days of treatment, airway inflammation and specific T- and B-cell responses were determined. Cell transfer experiments were also performed. CpG treatment attenuated airway allergic disease; however, the combination CpG/CFP treatment was significantly more effective in decreasing airway hyperresponsiveness, eosinophilia and Th2 response. When an additional intranasal dose of CFP was given, allergy was even more attenuated. The CpG/CFP therapy also reduced allergen-specific IgG1 and IgE antibodies and increased IgG2a. Transfer of spleen cells from mice immunized with CpG/CFP also reduced allergic lung inflammation. CpG/CFP treatment induced CFP-specific production of IFN-γ and IL-10 by spleen cells and increased production of IFN-γ in response to OVA. The essential role of IFN-γ for the therapeutic effect of CpG/CFP was evidenced in IFN-γ knockout mice. These results show that CpG/CFP treatment reverses established Th2 allergic responses by an IFN-γ-dependent mechanism that seems to act both locally in the lung and systemically to decrease allergen-specific Th2 responses.

Progress in understanding the pathophysiology of abdominal aortic aneurysms (AAA) is dependent in part on the development and application of effective animal models that recapitulate key aspects of the disease. The objective was to produce an experimental model of AAA in rats by combining two potential causes of metalloproteinase (MMP) secretion: inflammation and turbulent blood flow. Male Wistar rats were randomly divided in four groups: Injury, Stenosis, Aneurysm and Control (40/group). The Injury group received a traumatic injury to the external aortic wall. The Stenosis group received an extrinsic stenosis at a corresponding location. The Aneurysm group received both the injury and stenosis simultaneously, and the Control group received a sham operation. Animals were euthanized at days 1, 3, 7 and 15. Aorta and/or aneurysms were collected and the fragments were fixed for morphologic, immunohistochemistry and morphometric analyses or frozen for MMP assays. AAAs had developed by day 3 in 60–70% of the animals, reaching an aortic dilatation ratio of more than 300%, exhibiting intense wall remodelling initiated at the adventitia and characterized by an obvious inflammatory infiltrate, mesenchymal proliferation, neoangiogenesis, elastin degradation and collagen deposition. Immunohistochemistry and zymography studies displayed significantly increased expressions of MMP-2 and MMP-9 in aneurysm walls compared to other groups. The haemo-dynamic alterations caused by the stenosis may have provided additional contribution to the MMPs liberation. This new model illustrated that AAA can be multifactorial and confirmed the key roles of MMP-2 and MMP-9 in this dynamic remodelling process.

There is considerable evidence that consumption of fruits and vegetables may contribute to the prevention of cancer. It is however remarkable that evidence for such a preventive action arising from mechanistic studies is becoming stronger, whereas results of some recent prospective studies are less convincing. This apparent discrepancy may be overcome, or at least understood, by introducing molecular markers in future epidemiological studies, taking modulation of molecular processes as well as genetic variability in human populations into account. Both human and animal studies demonstrated that vegetable intake modulates gene expression in the gastrointestinal tract of many genes involved in biological pathways in favor of cancer risk prevention. Gene sets identified in this type of studies can be further evaluated, linked to the biological effects of phytochemicals and developed into biomarkers for larger human studies. Human dietary intervention studies have demonstrated that, apart from target tissues, also peripheral lymphocytes can be used for biomonitoring of chemopreventive effects. Transcriptomic responses and metabolite profiling may link phenotypic markers of preventive effects to specific molecular processes. The use of genomics techniques appears to be a promising approach to establish mechanistic pathways involved in chemoprevention by phytochemicals, particularly when genetic variability is taken into account.

We have used an experimental model of aorta stenosis, with a Plexiglas plug, simulating a stable atheromatous plaque that promotes local turbulence and thrombosis. With animal survival of more than 24 h, we followed the partial fibrinolysis of the thrombus as well as its posterior organization and incorporation to the arterial wall as a neointima for up to 30 days. The mushroom plug form permitted the development of recirculation and stasis areas around it, favouring this evolution. Despite noted limitations, this study demonstrates that thrombus incorporation can contribute to plaque extension, as it can promote recirculation and stasis areas.

Background The continued increase in tuberculosis (TB) rates and the appearance of extremely resistant Mycobacterium tuberculosis strains (XDR-TB) worldwide are some of the great problems of public health. In this context, DNA immunotherapy has been proposed as an effective alternative that could circumvent the limitations of conventional drugs. Nonetheless, the molecular events underlying these therapeutic effects are poorly understood. Methods We characterized the transcriptional signature of lungs from mice infected with M. tuberculosis and treated with heat shock protein 65 as a genetic vaccine (DNAhsp65) combining microarray and real-time polymerase chain reaction analysis. The gene expression data were correlated with the histopathological analysis of lungs. Results The differential modulation of a high number of genes allowed us to distinguish DNAhsp65-treated from nontreated animals (saline and vector-injected mice). Functional analysis of this group of genes suggests that DNAhsp65 therapy could not only boost the T helper (Th)1 immune response, but also could inhibit Th2 cytokines and regulate the intensity of inflammation through fine tuning of gene expression of various genes, including those of interleukin-17, lymphotoxin A, tumour necrosis factor-α, interleukin-6, transforming growth factor-β, inducible nitric oxide synthase and Foxp3. In addition, a large number of genes and expressed sequence tags previously unrelated to DNA-therapy were identified. All these findings were well correlated with the histopathological lesions presented in the lungs. Conclusions The effects of DNA therapy are reflected in gene expression modulation; therefore, the genes identified as differentially expressed could be considered as transcriptional biomarkers of DNAhsp65 immunotherapy against TB. The data have important implications for achieving a better understanding of gene-based therapies. Copyright © 2008 John Wiley & Sons, Ltd.

Taking into account that atherosclerosis is a focal disease and high levels of plasma cholesterol are closely correlated with its pathogenesis, it is a challenge to explain how equal concentrations of cholesterol bathing the endothelium can produce local, rather than global, effects on arteries. The focal distribution of atherosclerotic lesions has been considered to be dependent, at least in part, on hydrodynamic factors. The present study was carried out to further test the hypothesis that these forces are an important localizing factor in rats feeding a hypercholesterolaemic diet and submitted to infra-diaphragmatic aortic constriction. These animals develop a normotensive prestenotic region with laminar blood flow that serves as control for a normotensive poststenotic region with turbulent blood flow. Our findings clearly demonstrated that the combination of turbulent blood flow and low wall shear stress (WSS) in the presence of hypercholesterolaemia and oxidative stress creates conditions to the formation of focally distributed incipient atherosclerotic lesions observed in the poststenotic segment. In contrast, only diffuse fatty streaks could be observed in the normotensive prestenotic segment with laminar blood flow and normal WSS in the presence of hypercholesterolaemia and oxidative stress. Although haemodynamic forces are not by themselves responsible for the pathogenesis of atherosclerosis, they prime the local vascular wall in which the lesion develop. Further studies are required to establish how haemodynamic forces are detected and transduced into chemical signalling by the cells of the artery wall and then converted into pathophysiologically relevant phenotypic changes.