1,496 research outputs found
Small intestinal eosinophils regulate Th17 cells by producing IL-1 receptor antagonist
Eosinophils play proinflammatory roles in helminth infections and allergic diseases. Under steady-state conditions, eosinophils are abundantly found in the small intestinal lamina propria, but their physiological function is largely unexplored. In this study, we found that small intestinal eosinophils down-regulate Th17 cells. Th17 cells in the small intestine were markedly increased in the Delta dblGATA-1 mice lacking eosinophils, and an inverse correlation was observed between the number of eosinophils and that of Th17 cells in the small intestine of wild-type mice. In addition, small intestinal eosinophils suppressed the in vitro differentiation of Th17 cells, as well as IL-17 production by small intestinal CD4(+) T cells. Unlike other small intestinal immune cells or circulating eosinophils, we found that small intestinal eosinophils have a unique ability to constitutively secrete high levels of IL-1 receptor antagonist (IL-1Ra), a natural inhibitor of IL-1 beta. Moreover, small intestinal eosinophils isolated from IL-1Ra-deficient mice failed to suppress Th17 cells. Collectively, our results demonstrate that small intestinal eosinophils play a pivotal role in the maintenance of intestinal homeostasis by regulating Th17 cells via production of IL-1Ra.open111815sciescopu
Oral immunization of haemaggulutinin H5 expressed in plant endoplasmic reticulum with adjuvant saponin protects mice against highly pathogenic avian influenza A virus infection
Pandemics in poultry caused by the highly pathogenic avian influenza (HPAI) A virus occur too frequently globally, and there is growing concern about the HPAI A virus due to the possibility of a pandemic among humans. Thus, it is important to develop a vaccine against HPAI suitable for both humans and animals. Various approaches are underway to develop such vaccines. In particular, an edible vaccine would be a convenient way to vaccinate poultry because of the behaviour of the animals. However, an edible vaccine is still not available. In this study, we developed a strategy of effective vaccination of mice by the oral administration of transgenic Arabidopsis plants (HA-TG) expressing haemagglutinin (HA) in the endoplasmic reticulum (ER). Expression of HA in the ER resulted in its high-level accumulation, N-glycosylation, protection from proteolytic degradation and long-term stability. Oral administration of HA-TG with saponin elicited high levels of HA-specific systemic IgG and mucosal IgA responses in mice, which resulted in protection against a lethal influenza virus infection with attenuated inflammatory symptoms. Based on these results, we propose that oral administration of freeze-dried leaf powders from transgenic plants expressing HA in the ER together with saponin is an attractive strategy for vaccination against influenza A virus.X111411Ysciescopu
Inhibiting LXRĪ± phosphorylation in hematopoietic cells reduces inflammation and attenuates atherosclerosis and obesity in mice
Atherosclerosis and obesity share pathological features including inflammation mediated by innate and adaptive immune cells. LXRĪ± plays a central role in the transcription of inflammatory and metabolic genes. LXRĪ± is modulated by phosphorylation at serine 196 (LXRĪ± pS196), however, the consequences of LXRĪ± pS196 in hematopoietic cell precursors in atherosclerosis and obesity have not been investigated. To assess the importance of LXRĪ± phosphorylation, bone marrow from LXRĪ±Ā WT and S196A mice was transplanted into Ldlr-/- mice, which were fed a western diet prior to evaluation of atherosclerosis and obesity. Plaques from S196A mice showed reduced inflammatory monocyte recruitment, lipid accumulation, and macrophage proliferation. Expression profiling of CD68+ and T cells from S196A mouse plaques revealed downregulation of pro-inflammatory genes and in the case of CD68+ upregulation of mitochondrial genes characteristic of anti-inflammatory macrophages. Furthermore, S196A mice had lower body weight and less visceral adipose tissue; this was associated with transcriptional reprograming of the adipose tissue macrophages and T cells, and resolution of inflammation resulting in less fat accumulation within adipocytes. Thus, reducing LXRĪ± pS196 in hematopoietic cells attenuates atherosclerosis and obesity by reprogramming the transcriptional activity of LXRĪ± in macrophages and T cells to promote an anti-inflammatory phenotype
Therapeutic foam scaffolds incorporating biopolymer-shelled mesoporous nanospheres with growth factors
Here we report a novel therapeutic scaffolding system of engineered nanocarriers within a foam matrix for the long-term and sequential delivery of growth factors. For this, mesoporous silica nanospheres were first functionalized to have enlarged mesopore size (eMSNs, 12.2 nm) and aminated surface, which was then shelled by a biopolymer, poly(lactic acid) (PLA) or poly(ethylene glycol) (PEG) via an electrospraying. The hybrid nanocarrier was subsequently combined with collagen to produce foam scaffolds. Bovine serum albumin (BSA), used as a model protein, was effectively loaded within the enlarged nanospheres. The biopolymer shell substantially prolonged the release period of BSA (over 2-3 weeks from shelled nanospheres vs. within 1 week from bare nanospheres), and the release rate was highly dependent on the shell composition (PEG > PLA). Collagen foam scaffolding of the shelled nanocarrier further slowed down the protein release while enabling the incorporation of a rapidly releasing protein, which is effective for the sequential protein delivery. Acidic fibroblast growth factor (aFGF), loaded onto the shelled-nanocarrier scaffolds, was released over a month at a highly sustainable rate, profiling a similar release pattern to BSA. Biological activity of the aFGF released from the system, as examined by the proliferative potential of osteoblastic precursor cells, showed a significant improvement in the case with aFGF. Furthermore, in vivo implantation of the aFGF-delivering system in a rat subcutaneous tissue for 2 weeks showed a substantially enhanced invasion of fibroblasts with a homogeneous population. Taken together, it is concluded that the biopolymer encapsulation of mesoporous nanospheres effectively prolongs the release of growth factors over weeks to a month, providing a nanocarrier platform for a long-term growth factor delivery, moreover, the foam scaffolding of the nanocarrier system will be a potential therapeutic 3D matrix for cell culture and tissue engineering
The Gaia-ESO Survey: Pre-Main Sequence Stars in the Young Open Cluster NGC 3293
The young open cluster NGC3293 is included in the observing program of the Gaia-ESO survey (GES). The radial velocity values provided have been used to assign cluster membership probabilities by means of a single-variable parametric analysis. These membership probabilities are compared to the results of the photometric membership assignment of NGC3293, based on UBV RI photometry. The agreement of the photometric and kinematic member samples amounts to 65%, and could increase to 70% as suggested by the analysis of the differences between both samples. A number of photometric PMS candidate members of spectral type F are found, which are confirmed by the results from VPHAS photometry and SED fitting for the stars in common with VPHAS and GES data sets. Excesses at mid- and near-infrared wavelengths, and signs of HĪ± emission, are investigated for them. Marginal presence of HĪ± emission or infilling is detected for the candidate members. Several of them exhibit moderate signs of U excess and weak excesses at mid-IR wavelengths. We suggest that these features originate from accretion disks in their last stages of evolution
Sweets, sweetened beverages, and risk of pancreatic cancer in a large population-based caseācontrol study
We examined the associations between sweets, sweetened and unsweetened beverages, and sugars and pancreatic cancer risk.
We conducted a population-based caseācontrol study (532 cases, 1,701 controls) and used multivariate logistic regression models to calculate odds ratios (OR) and 95% confidence intervals (CI). Because associations were often different by sex, we present results for men and women combined and separately.
Among men, greater intakes of total and specific sweets were associated with pancreatic cancer risk (total sweets: ORĀ =Ā 1.9, 95% CI: 1.0, 3.6; sweet condiments: ORĀ =Ā 1.9, 95% CI: 1.2, 3.1; chocolate candy: ORĀ =Ā 2.4, 95% CI: 1.1, 5.0; other mixed candy bars: ORĀ =Ā 3.3, 95% CI: 1.5, 7.3 for 1Ā +Ā servings/day versus none/rarely). Sweets were not consistently associated with risk among women. Sweetened beverages were not associated with increased pancreatic cancer risk. In contrast, low-calorie soft drinks were associated with increased risk among men only; while other low-/non-caloric beverages (e.g., coffee, tea, and water) were unassociated with risk. Of the three sugars assessed (lactose, fructose, and sucrose), only the milk sugar lactose was associated with pancreatic cancer risk (ORĀ =Ā 2.0, 95% CI: 1.5, 2.7 comparing extreme quartiles).
These results provide limited support for the hypothesis that sweets or sugars increase pancreatic cancer risk
Understanding economic evidence for the prevention and treatment of atopic eczema
Background Atopic eczema is an inflammatory skin condition, with a similar impact on health-related quality-of-life as other chronic diseases. Increasing pressures on resources within the NHS increase the importance of having good economic evidence to inform their allocation. This paper aims to educate dermatologists about economic methods with illustration to currently available economic evidence on eczema. Methods/design The type and role of different types of economic evidence is illustrated by evidence found in a systematic literature search conducted across 12 online databases published until 22nd May 2017. Primary empirical studies either reporting the results of a cost of illness study or evaluating the cost, utility or full economic evaluation of interventions for preventing or treating eczema were included. Two reviewers independently assessed studies for eligibility and performed data abstraction, with disagreements resolved by a third reviewer. Evidence tables of results were produced for narrative discussion. The reporting quality of economic evaluations was assessed. Results 78 studies (described in 80 papers) were deemed eligible. 33 (42%) were judged to be economic evaluations, 12 (15%) cost analyses, 6 (8%) utility analyses, 26 (34%) cost-of-illness studies and 1 feasibility study (1%). The calcineurin inhibitors: tacrolimus and pimecrolimus, as well as barrier creams had most economic evidence available. Partially hydrolysed infant formula was the most commonly evaluated prevention. Conclusions The current level of economic evidence for interventions aimed at preventing and treating eczema is limited compared to that available for clinical outcomes suggesting that greater collaboration between clinicians and economists might be beneficial
Subfunctionalization reduces the fitness cost of gene duplication in humans by buffering dosage imbalances
<p>Abstract</p> <p>Background</p> <p>Driven essentially by random genetic drift, subfunctionalization has been identified as a possible non-adaptive mechanism for the retention of duplicate genes in small-population species, where widespread deleterious mutations are likely to cause complementary loss of subfunctions across gene copies. Through subfunctionalization, duplicates become indispensable to maintain the functional requirements of the ancestral locus. Yet, gene duplication produces a dosage imbalance in the encoded proteins and thus, as investigated in this paper, subfunctionalization must be subject to the selective forces arising from the fitness bottleneck introduced by the duplication event.</p> <p>Results</p> <p>We show that, while arising from random drift, subfunctionalization must be inescapably subject to selective forces, since the diversification of expression patterns across paralogs mitigates duplication-related dosage imbalances in the concentrations of encoded proteins. Dosage imbalance effects become paramount when proteins rely on obligatory associations to maintain their structural integrity, and are expected to be weaker when protein complexation is ephemeral or adventitious. To establish the buffering effect of subfunctionalization on selection pressure, we determine the packing quality of encoded proteins, an established indicator of dosage sensitivity, and correlate this parameter with the extent of paralog segregation in humans, using species with larger population -and more efficient selection- as controls.</p> <p>Conclusions</p> <p>Recognizing the role of subfunctionalization as a dosage-imbalance buffer in gene duplication events enabled us to reconcile its mechanistic nonadaptive origin with its adaptive role as an enabler of the evolution of genetic redundancy. This constructive role was established in this paper by proving the following assertion: <it>If subfunctionalization is indeed adaptive, its effect on paralog segregation should scale with the dosage sensitivity of the duplicated genes</it>. Thus, subfunctionalization becomes adaptive in response to the selection forces arising from the fitness bottleneck imposed by gene duplication.</p
Contribution of HOGG1 Ser326Cys Polymorphism to the Development of Prostate Cancer in Smokers: Meta-Analysis of 2779 Cases and 3484 Controls
The HOGG1 gene catalyzes the excision of modified bases and removal of DNA damage adducts. It may play an important role in the prevention of carcinogenesis. Ser326Cys polymorphism localizes in exon 7 of the hOGG1 gene. It takes the form of an amino acid substitution, from serine to cysteine, in codon 326. Several epidemiological association studies have been conducted on this polymorphism and its relationship with the risk of prostate cancer. However, results have been conflicting. To resolve this conflict, we conducted a meta-analysis on the association between this polymorphism and prostate cancer, taking into account race, country, sources of controls, and smoking status. A total of nine studies covering 2779 cases and 3484 controls were included in the current meta-analysis. Although no significant association was found between hOGG1 Ser326Cys polymorphism and prostate cancer susceptibility in the pooled analysis, individuals with Ser/Cys+Cys/Cys genotypes were found to have greater risk of prostate cancer if they were also smokers (ORā=ā2.66, 95% CIā=ā1.58ā4.47) rather than non-smokers (ORā=ā2.18, 95% CIā=ā1.13ā4.19), compared with those with Ser/Ser genotype. In conclusion, our meta-analysis demonstrates that hOGG1 Ser326Cys polymorphism is a risk factor for prostate cancer in smokers. Further studies are needed to confirm this relationship
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