Aryl hydrocarbon receptor (AhR), a transcription factor of the bHLH/PAS family, is well characterized to regulate the biochemical and toxic effects of environmental chemicals. More recently, AhR ...activation has been shown to regulate the differentiation of Foxp3(+) Tregs as well as Th17 cells. However, the precise mechanisms are unclear. In the current study, we investigated the effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent AhR ligand, on epigenetic regulation leading to altered Treg/Th17 differentiation, and consequent suppression of colitis.
Dextran sodium sulphate (DSS) administration induced acute colitis in C57BL/6 mice, as shown by significant weight loss, shortening of colon, mucosal ulceration, and increased presence of CXCR3(+) T cells as well as inflammatory cytokines. Interestingly, a single dose of TCDD (25 µg/kg body weight) was able to attenuate all of the clinical and inflammatory markers of colitis. Analysis of T cells in the lamina propria (LP) and mesenteric lymph nodes (MLN), during colitis, revealed decreased presence of Tregs and increased induction of Th17 cells, which was reversed following TCDD treatment. Activation of T cells from AhR(+/+) but not AhR (-/-) mice, in the presence of TCDD, promoted increased differentiation of Tregs while inhibiting Th17 cells. Analysis of MLN or LP cells during colitis revealed increased methylation of CpG islands of Foxp3 and demethylation of IL-17 promoters, which was reversed following TCDD treatment.
These studies demonstrate for the first time that AhR activation promotes epigenetic regulation thereby influencing reciprocal differentiation of Tregs and Th17 cells, and amelioration of inflammation.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Mucosal changes in Crohn's disease (CD) and ulcerative colitis (UC), two major forms of inflammatory bowel disease (IBD), are characterized by a prominent infiltration of inflammatory cells including ...lymphocytes, macrophages, T cells and neutrophils. The precise etiology of IBD is unknown but it involves a complex interplay of factors associated with the immune system, environment, host genotype and enteric commensal bacteria. As there is no known safe cure for IBD, natural alternative therapeutic options without side effects are urgently needed. To this end, Soy-based foods, which have been eaten for centuries in Asian countries, have potential benefits, including lowering the incidence of coronary heart disease, atherosclerosis, type-2 diabetes, allergic response, and autoimmune diseases. This study describes the effect of Soy isoflavons 4', 5, 7 Trihydroxyisoflavone (genistein) on dextran sodium sulphate (DSS) induced experimental colitis. The extent and severity of disease was analyzed through body weight, histopathological analysis, cellular immune response, systemic cytokine levels, and inflammation score using a disease activity index. Genistein treatment significantly attenuated DSS-induced colitis severity and resulted in increase in body weight, colon length and reduction in inflammation score. Genistein also skews M1 macrophages towards the M2 phenotype. Further, gen also reduced the systemic cytokine levels as compared to vehicle control. This serves as the first detailed study towards natural soya based product that shows the polarization of M1 towards M2 macrophages, and reduction of systemic cytokine in part to attenuate the colitis symptoms. Thus, our work demonstrates that genistein, a soya compound, may be useful for the treatment of IBD.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Our detailed 3-D seismic tomographic assimilation using high-quality phase arrival time data recorded by the local seismographic network demonstrated that heterogeneities in the crustal ...faults have contributed significantly to the pop-up tectonics beneath the Shillong Plateau, characterized by high-V and low-σ. The major seismogenic faults, namely, the north-dipping Dapsi thrust in association with Dauki fault in the south and south dipping Brahmaputra fault in the north, located either side of the Shillong Plateau that acted as the causative factors for the pop-up, which attributed to the lithostatic (high-V, low-σ) and sedimentary (low-V, high-σ) load, respectively. Seismicity is found confined to a depth ≤ 60 km. Uneven distribution of structural heterogeneities in the upper crust is responsible for earthquake genesis of varying strengths. It is intriguing to note that high-velocity anomalies and low-ϭ in the uppermost crust, interpreted as the Shillong Plateau that acted as a geometric asperity and the juxtaposition of high-V and low-V became the source zone of the 1897 Shillong earthquake (M
s
8.7) as a novel observation for the region. Structural heterogeneities are distinctly distributed between low-V, high-σ and high-V, low-σ in the lower crust plays a major role for future intense seismogenesis due to differential strain accumulation.
Entropy Theory and its Application in Environmental and Water Engineering responds to the need for a book that deals with basic concepts of entropy theory from a hydrologic and water engineering ...perspective and then for a book that deals with applications of these concepts to a range of water engineering problems. The range of applications of entropy is constantly expanding and new areas finding a use for the theory are continually emerging. The applications of concepts and techniques vary across different subject areas and this book aims to relate them directly to practical problems of environmental and water engineering.The book presents and explains the Principle of Maximum Entropy (POME) and the Principle of Minimum Cross Entropy (POMCE) and their applications to different types of probability distributions. Spatial and inverse spatial entropy are important for urban planning and are presented with clarity. Maximum entropy spectral analysis and minimum cross entropy spectral analysis are powerful techniques for addressing a variety of problems faced by environmental and water scientists and engineers and are described here with illustrative examples.Giving a thorough introduction to the use of entropy to measure the unpredictability in environmental and water systems this book will add an essential statistical method to the toolkit of postgraduates, researchers and academic hydrologists, water resource managers, environmental scientists and engineers. It will also offer a valuable resource for professionals in the same areas, governmental organizations, private companies as well as students in earth sciences, civil and agricultural engineering, and agricultural and rangeland sciences. This book:Provides a thorough introduction to entropy for beginners and more experienced usersUses numerous examples to illustrate the applications of the theoretical principlesAllows the reader to apply entropy theory to the solution of practical problemsAssumes minimal existing mathematical knowledgeDiscusses the theory and its various aspects in both univariate and bivariate casesCovers newly expanding areas including neural networks from an entropy perspective and future developments.
Leaf rust (Puccinia triticina Eriks.) is a fungal disease of wheat (Triticum spp.), which causes considerable yield loss. Adult plant resistance (APR) is one of the most sustainable approaches to ...control leaf rust. In this study, field-testing was carried out across ten different locations, followed by molecular screening, to detect the presence of APR genes, Lr34+, Lr46+, Lr67+ and Lr68 in Indian wheat germplasm. In field screening, 190 wheat accessions were selected from 6,319 accessions based on leaf tip necrosis (LTN), disease severity and the average coefficient of infection. Molecular screening revealed that 73% of the accessions possessed known APR genes either as single or as a combination of two or three genes. The occurrence of increased LTN intensity, decreased leaf rust severity and greater expression of APR genes were more in relatively cooler locations. In 52 lines, although the presence of the APR genes was not detected, it still displayed high levels of resistance. Furthermore, 49 accessions possessing either two or three APR genes were evaluated for stability across locations for grain yield. It emerged that eight accessions had wider adaptability. Resistance based on APR genes, in the background of high yielding cultivars, is expected to provide a high level of race non-specific resistance, which is durable.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This minireview explores the environmental bioremediation mediated by genetically engineered (GE) bacteria and it also highlights the limitations and challenges associated with the release of ...engineered bacteria in field conditions. Application of GE bacteria based remediation of various heavy metal pollutants is in the forefront due to eco-friendly and lesser health hazards compared to physico-chemical based strategies, which are less eco-friendly and hazardous to human health. A combination of microbiological and ecological knowledge, biochemical mechanisms and field engineering designs would be an essential element for successful in situ bioremediation of heavy metal contaminated sites using engineered bacteria. Critical research questions pertaining to the development and implementation of GE bacteria for enhanced bioremediation have been identified and poised for possible future research. Genetic engineering of indigenous microflora, well adapted to local environmental conditions, may offer more efficient bioremediation of contaminated sites and making the bioremediation more viable and eco-friendly technology. However, many challenges are to be addressed concerning the release of genetically engineered bacteria in field conditions. There are possible risks associated with the use of GE bacteria in field condition, with particular emphasis on ways in which molecular genetics could contribute to the risk mitigation. Both environmental as well as public health concerns need to be addressed by the molecular biologists. Although bioremediation of heavy metals by using the genetically engineered bacteria has been extensively reviewed in the past also, but the bio-safety assessment and factors of genetic pollution have been never the less ignored.
Several observational studies have shown that statins may modify the risk of gastric cancer (GC). We carried out a systematic review and meta-analysis of studies evaluating the effect of statins on ...GC risk.
We conducted a systematic search of multiple databases up to December 2012. Studies that evaluated exposure to statins, reported GC outcomes and odds ratio (OR) or provided data for their estimation were included in the meta-analysis. Pooled OR estimates with 95% confidence intervals (CIs) were calculated using the random-effects model.
Eleven studies (eight observational, three post-hoc analyses of 26 clinical trials) reporting 5581 cases of GC were included. Meta-analysis showed a significant 32% reduction in GC risk with statin use (adjusted OR, 0.68; 95% CI, 0.51–0.91). After exclusion of one study which was contributing to considerable heterogeneity, a significant 16% reduction in GC risk was a more conservative, consistent estimate (adjusted OR, 0.84; 95% CI, 0.78–0.90). This chemopreventive association was present in both Asian (adjusted OR, 0.68; 95% CI, 0.53–0.87) and Western population (adjusted OR, 0.86; 95% CI, 0.79–0.93).
Meta-analysis of studies supports a protective association between statin use and GC risk, in both Asian and Western population, in a dose-dependent manner.
Gold nanoparticles decorated graphene oxide (Au-rGO) nanocomposite thin films with enhanced electro-active characteristics were prepared and covalently immobilized with uricase (UOx) enzyme for ...sensitive and selective detection of uric acid (UA). Differential pulse voltammetry (DPV) studies revealed rapid response of fabricated electrode towards UA at low potential (0.228 V) in a wide concentration range of 50–800 μM with a sensitivity of 86.62 ± 0.19 μA mM−1 and very low detection limit of 7.32 ± 0.21 μM. The obtained Michaelis-Menten constant (km) value of 51.75 μM signifies high enzyme kinetics at electrode surface with UA. The developed biosensor was successfully applied to detect UA in human serum samples. Interferences due to components present in the real matrix were evaluated and UA determination in mixed sample was also performed. The fabricated UOx/Au-rGO/ITO biosensor demonstrated high reproducibility and a shelf-life of 6 months indicating the promising future of Au-rGO nanocomposite as an efficient transducer matrix for biosensing applications. The fast response time (1.0 ± 0.6 s) and improved sensor performance is attributed to the synergistic electronic properties of Au-nanoparticles and rGO that provided enhanced electron transfer and high electro-active species surface coverage at Au-rGO nanocomposite.
Race Ug99 of the fungus Puccinia graminis tritici that causes stem or black rust disease on wheat was first detected in Uganda in 1998. Seven races belonging to the Ug99 lineage are now known and ...have spread to various wheat-growing countries in the eastern African highlands, as well as Zimbabwe, South Africa, Sudan, Yemen, and Iran. Because of the susceptibility of 90% of the wheat varieties grown worldwide, the Ug99 group of races was recognized as a major threat to wheat production and food security. Its spread, either wind-mediated or human-aided, to other countries in Africa, Asia, and beyond is evident. Screening in Kenya and Ethiopia has identified a low frequency of resistant wheat varieties and breeding materials. Identification and transfer of new sources of race-specific resistance from various wheat relatives is underway to enhance the diversity of resistance. Although new Ug99-resistant varieties that yield more than current popular varieties are being released and promoted, major efforts are required to displace current Ug99 susceptible varieties with varieties that have diverse race-specific or durable resistance and mitigate the Ug99 threat.
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