Background Single nucleotide polymorphisms in the human gene for the receptor for advanced glycation end-products (RAGE) are associated with an increased incidence of asthma. RAGE is highly expressed ...in the lung and has been reported to play a vital role in the pathogenesis of murine models of asthma/allergic airway inflammation (AAI) by promoting expression of the type 2 cytokines IL-5 and IL-13. IL-5 and IL-13 are prominently secreted by group 2 innate lymphoid cells (ILC2s), which are stimulated by the proallergic cytokine IL-33. Objective We sought to test the hypothesis that pulmonary RAGE is necessary for allergen-induced ILC2 accumulation in the lung. Methods AAI was induced in wild-type and RAGE knockout mice by using IL-33, house dust mite extract, or Alternaria alternata extract. RAGE's lung-specific role in type 2 responses was explored with bone marrow chimeras and induction of gastrointestinal type 2 immune responses. Results RAGE was found to drive AAI by promoting IL-33 expression in response to allergen and by coordinating the inflammatory response downstream of IL-33. Absence of RAGE impedes pulmonary accumulation of ILC2s in models of AAI. Bone marrow chimera studies suggest that pulmonary parenchymal, but not hematopoietic, RAGE has a central role in promoting AAI. In contrast to the lung, the absence of RAGE does not affect IL-33–induced ILC2 influx in the spleen, type 2 cytokine production in the peritoneum, or mucus hypersecretion in the gastrointestinal tract. Conclusions For the first time, this study demonstrates that a parenchymal factor, RAGE, mediates lung-specific accumulation of ILC2s.
Industrial robots are promising cost-effective and flexible alternatives for multi-axis milling applications in machining of complex parts of light materials with lower tolerances, having freeform ...surfaces. As it is well-known, the poor accuracy, stiffness, and the complexity of programming are the most important limiting factors for wider adoption of robotic machining in machine shops. The paper presents the developed method for off-line compensation of machining robot tool tip static displacements as a dominant part of cutting force-induced errors. The developed method is based on modification of programmed trajectory in G-code. Off-line modification of programmed trajectory is performed according to the predicted static tool tip displacements calculated based on developed robot compliance model and cutting forces predicted by mechanistic model. The obtained experimental results show the relevance of developed method since the machining errors could be significantly reduced. This allows the desired accuracy of robot machining to converge towards nominal specifications.
Background
The receptor for advanced glycation endproducts (RAGE) has been implicated as a critical molecule in the pathogenesis of experimental asthma/allergic airway inflammation (AAI). It has been ...previously shown that RAGE acts both upstream of interleukin‐33 (IL‐33) release and downstream of IL‐33 release via RAGE‐dependent IL‐33‐induced accumulation of type 2 innate lymphoid cells (ILC2s) in the lungs, which perpetuate type 2 inflammation and mucus metaplasia. However, the mechanism by which RAGE mediates downstream IL‐33‐induced type 2 inflammatory responses is unknown.
Objective
This study tested the hypothesis that ILC2s are recruited to the lungs via RAGE‐dependent vascular cell adhesion molecule 1 (VCAM‐1) expression on lung endothelial cells.
Methods
House dust mite extract, Alternaria alternata extract, or rIL‐33 was used to induce AAI/VCAM‐1 expression in wild‐type (WT) and RAGE‐knockout (RAGE‐KO) mice. Intravenous (i.v.) anti‐VCAM‐1 or intraperitoneal (i.p.) β7 blocking antibody administration was used to determine the role of VCAM‐1 in IL‐33‐induced AAI.
Results
Enhanced VCAM‐1 expression in the lungs by HDM, AA, or rIL‐33 exposure was found to be RAGE‐dependent. In addition, stimulation of primary mouse lung endothelial cells with IL‐33 induced VCAM‐1 expression in WT, but not RAGE‐KO cells. Administration of VCAM‐1 and β7‐integrin blocking antibodies reduced IL‐33‐induced eosinophilic inflammation, mucus metaplasia, and type 2 inflammatory responses.
Conclusion
This study demonstrates that allergen‐ and cytokine‐induced VCAM‐1 expression is RAGE‐dependent and contributes to lung ILC2 accumulation and downstream eosinophilic inflammation, mucus metaplasia, and type 2 inflammatory responses.
Exposure to allergens or recombinant interleukin‐(IL)‐33 induces expression of vascular cell adhesion molecule‐1 (VCAM‐1) in the lung endothelium in a RAGE‐dependent manner and activates type 2 innate lymphoid cells (ILC2). IL‐33 recruits ILC2s to the lungs, which produce IL‐5 and IL‐13, which induces eotaxin production, eosinophil recruitment, and mucus secretion. Blocking VCAM‐1 or β7 integrins with neutralizing antibodies inhibits IL‐33 induced eosinophilic inflammation and mucus production in the lungs. IL‐33 mediates ILC2 and eosinophil recruitment to the lungs through RAGE‐dependent VCAM‐1 expression and interaction with β7 integrins.
The insecticide DDT is an omnipresent environmental contaminant and an ongoing toxicological concern. The recent discovery that methylenetetrahydrofolate (MTHF) models are capable of reducing a range ...of halocarbons to hydrocarbons under biomimetic conditions has prompted us to investigate the possible role of MTHF in the metabolism of DDT. We now report that the reaction of MTHF models with DDT produces no less than five known in vivo metabolites of DDT, namely DDD, DDE, DDMU, DBP, and DDM. The capability of the MTHF models to produce the full spectrum of known DDT dehalogenation products is strong evidence that the mechanistically obscure metabolism of DDT may involve MTHF. The findings also suggest that DDT should be capable of disrupting folate-dependent pathways.
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•The interactions between MTHF model compounds and DDT are studied in vitro.•The full metabolite spectrum of DDT is obtained under aerobic and anaerobic conditions.•The degradation pathway of each individual DDT metabolite is mapped.•Formation of the metabolite DBP does not require cytochrome P450.
The receptor for advanced glycation end products (RAGE) is a multiligand receptor that has been shown to contribute to the pathogenesis of diabetes, atherosclerosis, and neurodegeneration. However, ...its role in asthma and allergic airway disease is largely unknown. These studies use a house dust mite (HDM) mouse model of asthma/allergic airway disease. Respiratory mechanics were assessed and compared between wild-type and RAGE knockout mice. Bronchovascular architecture was assessed with quantitative scoring, and expression of RAGE, immunoglobulins, and relevant cytokines was assessed by standard protein detection methods and/or quantitative RT-PCR. The absence of RAGE abolishes most assessed measures of pathology, including airway hypersensitivity (resistance, tissue damping, and elastance), eosinophilic inflammation, and airway remodeling. IL-4 secretion, isotype class switching, and antigen recognition are intact in the absence of RAGE. In contrast, normal increases in IL-5, IL-13, eotaxin, and eotaxin-2 production are abrogated in the RAGE knockouts. IL-17 indicates complex regulation, with elevated baseline expression in RAGE knockouts, but no induction in response to allergen. Treatment of WT mice with an inhibitor of RAGE markedly reduces inflammation in the HDM model, suggesting that RAGE inhibition may serve as a promising therapeutic strategy. Finally, the results in the HDM model are recapitulated in an ovalbumin model of asthma, suggesting that RAGE plays a role in asthma irrespective of the identity of the allergens involved.
The receptor for advanced glycation end-products (RAGE) has been suggested to modulate lung injury in models of acute pulmonary inflammation. To study this further, model systems utilizing wild type ...and RAGE knockout (KO) mice were used to determine the role of RAGE signaling in lipopolysaccharide (LPS) and E. coli induced acute pulmonary inflammation. The effect of intraperitoneal (i.p.) and intratracheal (i.t.) administration of mouse soluble RAGE on E. coli injury was also investigated.
C57BL/6 wild type and RAGE KO mice received an i.t. instillation of LPS, E. coli, or vehicle control. Some groups also received i.p. or i.t. administration of mouse soluble RAGE. After 24 hours, the role of RAGE expression on inflammation was assessed by comparing responses in wild type and RAGE KO. RAGE protein levels decreased in wild type lung homogenates after treatment with either LPS or bacteria. In addition, soluble RAGE and HMGB1 increased in the BALF after E. coli instillation. RAGE KO mice challenged with LPS had the same degree of inflammation as wild type mice. However, when challenged with E. coli, RAGE KO mice had significantly less inflammation when compared to wild type mice. Most cytokine levels were lower in the BALF of RAGE KO mice compared to wild type mice after E. coli injury, while only monocyte chemotactic protein-1, MCP-1, was lower after LPS challenge. Neither i.p. nor i.t. administration of mouse soluble RAGE attenuated the severity of E. coli injury in wild type mice.
Lack of RAGE in the lung does not protect against LPS induced acute pulmonary inflammation, but attenuates injury following live E. coli challenge. These findings suggest that RAGE mediates responses to E. coli-associated pathogen-associated molecular pattern molecules other than LPS or other bacterial specific signaling responses. Soluble RAGE treatment had no effect on inflammation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The reduction of halocarbons by NADH models and NADH under ambient conditions is reported as a new type of reactivity pointing towards a hitherto unknown disruptive pathway for NADH/NADPH-dependent ...processes. The reaction was studied with the omnipresent pesticide DDT, the inhalation anesthetic halothane, and several simple halocarbons. The halide–hydride exchange represents a biochemical equivalent for the reduction of halocarbons by traditional synthetic reagents like silanes (R3Si–H) and stannanes (R3Sn–H). High precision thermochemical calculations (CBS-QB3) reveal the carbon–hydrogen bond dissociation energy of NADH (70.8 kcal·mol−1) to be lower than that of stannane (SnH4: 78.1 kcal·mol−1), approaching that of the elusive plumbane (PbH4: 68.9 kcal·mol−1). The ready synthetic accessibility of NADH models, their low carbon–hydrogen bond dissociation energy, and their dehalogenation activity in the presence of air and moisture recommend these compounds as substitutes for the air-sensitive or toxic metal hydrides currently employed in synthesis.
•NADH models and NADH rapidly reduce a variety of simple halogenated compounds to hydrocarbons.•DDT is reductively dehalogenated by NADH models to three known DDT metabolites.•NADH has a very low bond dissociation energy (70.8 kcal·mol−1), comparable to stannanes, R3Sn–H.•Halocarbons are, in principle, capable of disrupting NADH-dependent pathways.
Halocarbons R-X are reduced to hydrocarbons R-H by folate model compounds under biomimetic conditions. The reactions correspond to a halide-hydride exchange with the methylenetetrahydrofolate (MTHF) ...models acting as hydride donors. The MTHF models are also functional equivalents of dehalohydrogenases but, unlike these enzymes, do not require a metal cofactor. The reactions suggest that halocarbons have the potential to act as endocrinological disruptors of biochemical pathways involving MTHF. As a case in point, we observe the rapid reaction of the MTHF models with the inhalation anaesthetic halothane. The ready synthetic accessibility of the MTHF models as well as their dehalogenation activity in the presence of air and moisture allow for the remediation of toxic, halogenated hydrocarbons.
Methylenetetrahydrofolate models (green substructure) reduce organohalides to the respective hydrocarbons under biomimetic conditions and mimic the activity of dehalohydrogenases.
In the hypothalamus, insulin takes on many roles involved in energy homoeostasis. Therefore, the aim of this study was to examine hypothalamic insulin expression during the initial phase of the ...metabolic response to fasting. Hypothalamic insulin content was assessed by both radioimmunoassay and Western blot. The relative expression of insulin mRNA was examined by qPCR. Immunofluorescence and immunohistochemistry were used to determine the distribution of insulin immunopositivity in the hypothalamus. After 6‐h fasting, both glucose and insulin levels were decreased in serum but not in the cerebrospinal fluid. Our study showed for the first time that, while the concentration of circulating glucose and insulin decreased, both insulin mRNA expression and insulin content in the hypothalamic parenchyma were increased after short‐term fasting. Increased insulin immunopositivity was detected specifically in the neurons of the hypothalamic periventricular nucleus and in the ependymal cells of fasting animals. These novel findings point to the complexity of mechanisms regulating insulin expression in the CNS in general and in the hypothalamus in particular.
Short‐term fasting increased the expression of insulin mRNA and protein insulin content in the rat hypothalamus. Increased insulin immunopositivity was detected in NeuN‐positive cells of periventricular nucleus and in ependymal cells around the third ventricle.
To distinguish patients (pts) with enthesitis having spondyloarthritis (SpA) from pts with enthesitis without SpA by ultrasound (US) enthesitis score.
The study sample included 127 pts with ...enthesitis (76 pts with SpA, 26 pts with rheumatoid arthritis, 25 pts with mechanically-related enthesitis). The entheses of plantar fascia, Achilles, patellar, quadriceps and common extensor tendon on lateral epicondyle were examined by US. Two operators, blinded to clinical diagnosis and enthesitis symptoms, assessed enthesis thickness, echogenicity, enthesophytes, power Doppler signal and erosions. Logistic regression and receiver operating characteristic (ROC) curve analysis were used to determine the predictive value of each enthesitis lesion for diagnosis of SpA. The best predictive value for SpA was accomplished when absence and presence of increased thickness, hypoechogenicity and enthesophytes were scored as 0 and 1; absence and presence of PD and erosions were scored as 0 and 4. Belgrade Ultrasound Enthesitis Score (BUSES) represents a cumulative score of derived enthesitis lesion scores at examined entheses. Independent-samples t-test was used for BUSES comparison between pts with and without SpA. Validity of BUSES for SpA diagnosis was evaluated by sensitivity and specificity. Cut-off point was chosen as the smallest value with specificity of at least 90%. The reliability was analysed by intra-class-correlation coefficient (ICC).
BUSES was 9.9 ± 12.4 (mean ± SD) in SpA pts and 3.1 ± 4.2 in pts without SpA (p<0.001). BUSES cut-off point ≥ 7 achieved excellent specificity (90.2%) and fair sensitivity (47.4%). ICC was 0.99.
BUSES is highly specific, valid and reliable to identify patients with SpA.
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