Changes in Functional Glucocorticoid Sensitivity of Isolated Splenocytes Induced by Chronic Psychosocial Stress - A Time Course Study.

Chronic psychosocial stress is a risk factor for the development of numerous disorders, of which most are associated with chronic low-grade inflammation. Given the immunosuppressive effects of glucocorticoids (GC), one underlying mechanism might be the development of stress-induced GC resistance in certain immune cell subpopulations. In line with this hypothesis, male mice exposed to the chronic subordinate colony housing (CSC, 19 days) model develop GC resistance of in vitro lipopolysaccharide (LPS)-stimulated splenocytes, splenomegaly and an increased percentage of splenic CD11b+ cells. Here male C57BL/6N mice were euthanized at different days during CSC, and following 30 days of single housing after stressor termination to assess when CSC-induced splenic GC resistance starts to develop and whether this is a transient effect. Moreover, splenic CD11b, GC receptor (GR) and/or macrophage migration inhibiting factor (MIF) protein levels were quantified at respective days. While mild forms of CSC-induced GC resistance, increased splenic CD11b expression and/or splenomegaly were detectable on days 8 and 9 of CSC, more severe forms took until days 15 and 16 to develop, but normalized almost completely within 30 days following stressor termination (day 51). In contrast, splenic GR expression was decreased in CSC versus single-housed control (SHC) mice at all days assessed. While MIF expression was increased on days 15 and 16 of CSC, it was decreased in CSC versus SHC mice on day 20 despite persisting splenomegaly, increased CD11b expression and functional GC resistance. In summary, our data indicate that GC resistance and CD11b+ cell-mediated splenomegaly develop gradually and in parallel over time during CSC exposure and are transient in nature. Moreover, while we can exclude that CSC-induced reduction in splenic GR expression is sufficient to induce functional GC resistance, the role of MIF in CD11b+ cell-mediated splenomegaly and GC resistance requires further investigation.

A Clinician's Guide for Trending Cardiovascular Nutrition Controversies: Part II.

The potential cardiovascular (CV) benefits of many trending foods and dietary patterns are still incompletely understood, and scientific inquiry continues to evolve. In the meantime, however, a number of controversial dietary patterns, foods, and nutrients have received significant media attention and are mired by "hype." This second review addresses some of the more recent popular foods and dietary patterns that are recommended for CV health to provide clinicians with current information for patient discussions in the clinical setting. Specifically, this paper delves into dairy products, added sugars, legumes, coffee, tea, alcoholic beverages, energy drinks, mushrooms, fermented foods, seaweed, plant and marine-derived omega-3-fatty acids, and vitamin B12.

Color stability, psychosocial impact, and effect on self-perception of esthetics of tooth whitening using low-concentration (6%) hydrogen peroxide.

OBJECTIVE: The aim of this study was to assess the bleaching efficacy and impact on psychosocial and esthetics self-perception of a low-concentration (6%) hydrogen peroxide (H2O2) gel compared with a conventional (37.5%) H2O2 gel when used as an in-office treatment. METHOD AND MATERIALS: In total, 35 participants received two sessions of three 12-minute applications of treatment with 37.5% H2O2 on one side of the mouth and 6% H2O2 on the other. Color changes were measured objectively using total variation in color (ΔE) and subjectively using Vita Classical scale (ΔSGU). The Psychosocial Impact of Dental Aesthetic Questionnaire (PIDAQ) and Oral Health Impact Profile (OHIP-14) esthetic questionnaires were administered to measure self-perception and the psychosocial impact of the whitening procedure. RESULTS: Both gels produced significant changes in tooth color at 1 and 3 months post-whitening. The objective efficacy (ΔE) of 37.5% H2O2 (9.06 ± 2.96) was significantly higher than that of 6% H2O2 (5.69 ± 3.06). The results of the subjective assessment were not statistically different. There was a positive impact on esthetic auto perception (OHIP-14, P < .05) and psychosocial impact (PIDAQ, P < .05) at the 3-month time point. CONCLUSION: Low concentration of H2O2 (6%) achieved effective bleaching (ΔE > 5 units) with good stability at 3 months accompanied by a positive psychosocial impact and enhanced self-perception. However, the traditional 35% concentration was objectively more effective.

Endothelial C-Type Natriuretic Peptide Acts on Pericytes to Regulate Microcirculatory Flow and Blood Pressure.

BACKGROUND: Peripheral vascular resistance has a major impact on arterial blood pressure levels. Endothelial C-type natriuretic peptide (CNP) participates in the local regulation of vascular tone, but the target cells remain controversial. The cGMP-producing guanylyl cyclase-B (GC-B) receptor for CNP is expressed in vascular smooth muscle cells (SMCs). However, whereas endothelial cell-specific CNP knockout mice are hypertensive, mice with deletion of GC-B in vascular SMCs have unaltered blood pressure. METHODS: We analyzed whether the vasodilating response to CNP changes along the vascular tree, ie, whether the GC-B receptor is expressed in microvascular types of cells. Mice with a floxed GC-B ( Npr2) gene were interbred with Tie2-Cre or PDGF-Rß-Cre ERT2 lines to develop mice lacking GC-B in endothelial cells or in precapillary arteriolar SMCs and capillary pericytes. Intravital microscopy, invasive and noninvasive hemodynamics, fluorescence energy transfer studies of pericyte cAMP levels in situ, and renal physiology were combined to dissect whether and how CNP/GC-B/cGMP signaling modulates microcirculatory tone and blood pressure. RESULTS: Intravital microscopy studies revealed that the vasodilatatory effect of CNP increases toward small-diameter arterioles and capillaries. CNP consistently did not prevent endothelin-1-induced acute constrictions of proximal arterioles, but fully reversed endothelin effects in precapillary arterioles and capillaries. Here, the GC-B receptor is expressed both in endothelial and mural cells, ie, in pericytes. It is notable that the vasodilatatory effects of CNP were preserved in mice with endothelial GC-B deletion, but abolished in mice lacking GC-B in microcirculatory SMCs and pericytes. CNP, via GC-B/cGMP signaling, modulates 2 signaling cascades in pericytes: it activates cGMP-dependent protein kinase I to phosphorylate downstream targets such as the cytoskeleton-associated vasodilator-activated phosphoprotein, and it inhibits phosphodiesterase 3A, thereby enhancing pericyte cAMP levels. These pathways ultimately prevent endothelin-induced increases of pericyte calcium levels and pericyte contraction. Mice with deletion of GC-B in microcirculatory SMCs and pericytes have elevated peripheral resistance and chronic arterial hypertension without a change in renal function. CONCLUSIONS: Our studies indicate that endothelial CNP regulates distal arteriolar and capillary blood flow. CNP-induced GC-B/cGMP signaling in microvascular SMCs and pericytes is essential for the maintenance of normal microvascular resistance and blood pressure.

Effect of gender of the operator and application mode of adhesives on dentin hydraulic conductance in an in vitro model

ABSTRACT: Aim: To compare the hydraulic conductance of human dentin disks which have been treated with an adhesive by operators of different genders and by active or passive modes of application. 60 third molars of healthy adults were included in resin blocks. These were cut to obtain 60 dentin disks of 1mm +/- 0.1 mm thick. Group 1 and 2, the adhesive was applied by 15 male operators passively (group 1) and vigorously (group 2). Groups 3 and 4, the adhesive was applied by 15 female operators passively (group 3) and vigorously (group 4). The flow rate was measured with a diffusion chamber and the hydraulic conductance of the disks was determined. Results: Mean for hydraulic conductance of each group was: 1 (0.01752), 2 (0.00355), 3 (0.01215), 4 (0.00877) in μl/minxcm2. There was statistically significant difference in the hydraulic conductance between experimental and control groups. There was no difference in dentin hydraulic conductance between genders. There was statistically significant difference in hydraulic conductance between the different modes of application. There was a moderate association between the pressure exerted when applying the adhesive and the values of dentin hydraulic conductance in vitro.

Influence of the passive evaporation of adhesive on the conductance of dentin

ABSTRACT: Aim: Determine the influence of time of passive evaporation of the solvent in a universal adhesive on the hydraulic conductance and permeability of dentin in an ex vivo human model. Henceforth, 60 healthy non-occluding third molars, indicated for therapeutic extraction/removal, of informed and consented patients aged between 18 and 30 years, were used here in. First, extracted teeth were incorporated into epoxy resin blocks and then dentin disks (1mm +/- 0.1 mm thick) were prepared. Dentin was acid etched with 35% ortho-phosphoric acid for 15 seconds in order to remove the smear layer and obtain permeable dentin. Samples were then randomized and divided into 5 groups (n=12). A Single Bond Universal adhesive layer with different time of passive evaporation of the solvent was then applied: GC=10 seconds, G1=30 seconds, G2=60 seconds, G3=300 seconds and G4=50 minutes. Finally, the flow rate was measured using a diffusion chamber, a model previously proposed by Pashley et al. Results: The obtained hydraulic conductance averages were as follows: GC=0.00052, G1=0.00018, G2=0.00006, G3=0.00005, G4=0.00005 expressed in uL•cm-2•min-1cm•H2O-1. For comparisons between groups, ANOVA and post hoc Tukey (ρ<0.05) tests were applied, resulting in a statistically significant difference between the GC group and all experimental groups (ρ <0.05). An influence of solvent passive evaporation thereby reducing hydraulic conductance in the experimental groups, was detected.

Sclerosing encapsulating peritonitis: a case report.

Sclerosing encapsulating peritonitis, a rare cause of bowel obstruction, was described as a complication associated with peritoneal dialysis which is much feared because of its severity. The authors report a case where radiological findings in association with clinical symptoms have allowed for a noninvasive diagnosis of sclerosing encapsulating peritonitis, emphasizing the high sensitivity and specificity of computed tomography to demonstrate the characteristic findings of such a condition.

Peritonite esclerosante encapsulante, causa rara de obstrução intestinal, foi descrita como uma complicação associada à diálise peritoneal, muito temida por sua gravidade. Relata-se um caso em que os achados radiológicos associados aos sintomas clínicos permitiram o diagnóstico não invasivo de peritonite esclerosante encapsulante, destacando-se a alta sensibilidade e especificidade da tomografia computadorizada na demonstração dos achados característicos.

Sclerosing encapsulating peritonitis: a case report / Peritonite esclerosante encapsulante: relato de caso

Sclerosing encapsulating peritonitis, a rare cause of bowel obstruction, was described as a complication associated with peritoneal dialysis which is much feared because of its severity. The authors report a case where radiological findings in association with clinical symptoms have allowed for a noninvasive diagnosis of sclerosing encapsulating peritonitis, emphasizing the high sensitivity and specificity of computed tomography to demonstrate the characteristic findings of such a condition.

Peritonite esclerosante encapsulante, causa rara de obstrução intestinal, foi descrita como uma complicação associada à diálise peritoneal, muito temida por sua gravidade. Relata-se um caso em que os achados radiológicos associados aos sintomas clínicos permitiram o diagnóstico não invasivo de peritonite esclerosante encapsulante, destacando-se a alta sensibilidade e especificidade da tomografia computadorizada na demonstração dos achados característicos.

The ureide-degrading reactions of purine ring catabolism employ three amidohydrolases and one aminohydrolase in Arabidopsis, soybean, and rice.

Several ureides are intermediates of purine base catabolism, releasing nitrogen from the purine nucleotides for reassimilation into amino acids. In some legumes like soybean (Glycine max), ureides are used for nodule-to-shoot translocation of fixed nitrogen. Four enzymes of Arabidopsis (Arabidopsis thaliana), (1) allantoinase, (2) allantoate amidohydrolase (AAH), (3) ureidoglycine aminohydrolase, and (4) ureidoglycolate amidohydrolase (UAH), catalyze the complete hydrolysis of the ureide allantoin in vitro. However, the metabolic route in vivo remains controversial. Here, in growth and metabolite analyses of Arabidopsis mutants, we demonstrate that these enzymes are required for allantoin degradation in vivo. Orthologous enzymes are present in soybean, encoded by one to four gene copies. All isoenzymes are active in vitro, while some may be inefficiently translated in vivo. Surprisingly, transcript and protein amounts are not significantly regulated by nitrogen fixation or leaf ureide content. A requirement for soybean AAH and UAH for ureide catabolism in leaves has been demonstrated by the use of virus-induced gene silencing. Functional AAH, ureidoglycine aminohydrolase, and UAH are also present in rice (Oryza sativa), and orthologous genes occur in all other plant genomes sequenced to date, indicating that the amidohydrolase route of ureide degradation is universal in plants, including mosses (e.g. Physcomitrella patens) and algae (e.g. Chlamydomomas reinhardtii).

Dentin hypersensitivity after teeth bleaching with in-office systems. Randomized clinical trial.

PURPOSE: To comparatively and prospectively compare in a randomized clinical trial, dentin hypersensitivity after treatment with three in-office bleaching systems, based on hydrogen peroxide at different concentrations, with and without light source activation. METHODS: 88 individuals were included according to inclusion and exclusion criteria. Subjects were randomly divided into the following three treatment groups: Group 1 was treated with three 15-minute applications of hydrogen peroxide at 15% with titanium dioxide (Lase Peroxide Lite) that was light-activated (Light Plus Whitening Lase) with five cycles of 1 minute and 30 seconds each cycle, giving a total treatment time of 45 minutes; Group 2 was treated with three 10-minute applications of hydrogen peroxide at 35% (Lase Peroxide Sensy), activated by light (LPWL) same activation cycles than Group 1, with a total treatment time of 30 minutes; Group 3 was treated with only one application for 45 minutes of hydrogen peroxide at 35% (Whitegold Office) without light activation. Each subject underwent one session of bleaching on the anterior teeth according to the manufacturers' instructions. Dentin sensitivity was recorded with a visual analogue scale (VAS) at baseline, immediately after, and at 7 and 30 days after treatment using a stimulus of an evaporative blowing triple syringe for 3 seconds on the upper central incisors from a distance of 1 cm. A Kruskal-Wallis test followed by Mann-Whitney test was performed for statistical analysis. RESULTS: All groups showed increased sensitivity immediately after treatment. Group 1 displayed less changes relative to baseline with no significant differences (P = 0.104). At 7 and 30 days after treatment, a comparison of VAS values indicated no significant differences between all groups (P = 0.598 and 0.489, respectively).

Lip competence in Class III patients undergoing orthognathic surgery: an electromyographic study.

PURPOSE: The aim of this study was to compare the presurgical and postsurgical electromyographic (EMG) activities of the lips in patients with skeletal Class III treated with combined orthognathic surgery and contrast these data with those obtained from a control group with skeletal Class I. PATIENTS AND METHODS: Ten patients with skeletal Class III underwent the registration of EMG activity before an orthognathic surgical procedure and 4 months after surgery. The results were compared with a control group of 11 healthy patients with skeletal Class I and clinical and EMG lip competence. EMG activity was recorded from the upper orbicularis oris and mentalis muscles during swallowing, lips in contact (LC), and lips apart (LA) using bipolar surface electrodes. The competence condition was assessed by determining the difference in the EMG activity of the mentalis muscle (LC-LA ≤0 for lip competence). RESULTS: Patients with skeletal Class III showed greater EMG activity than the control group before and after surgery. Patients with skeletal Class III showed a significantly greater difference in LC-LA than the control group before surgery for the 2 muscles (P < .05). No significant difference was found between the skeletal Class III group after surgery and the control group for the mentalis muscle (P > .05). CONCLUSIONS: Four months after treatment with orthognathic surgery, patients with skeletal Class III and an initial muscle activity pattern of lip incompetence different from the control group (P < .05) showed EMG values compatible with lip competence. These values were similar to the control group.

The biochemistry of nitrogen mobilization: purine ring catabolism.

The enzymatic route of purine ring catabolism has recently been completed by the discovery of several novel enzymes identified through comparative genome analyses. Here, we review these recent discoveries and present an overview of purine ring catabolism in plants. Xanthine is oxidized to urate in the cytosol, followed by three enzymatic steps taking place in the peroxisome and four reactions in the endoplasmic reticulum releasing the four ring nitrogen as ammonia. Although the main physiological function of purine degradation might lie in the remobilization of nitrogen resources, it has also emerged that catabolic intermediates, the ureides allantoin and allantoate, are likely to be involved in protecting plants against abiotic stress. Conserved alternative splicing mediating the peroxisomal as well as cytosolic localization of allantoin synthase potentially links purine ring catabolism to brassinosteroid signaling.

Identification and characterization of proteins involved in rice urea and arginine catabolism.

Rice (Oryza sativa) production relies strongly on nitrogen (N) fertilization with urea, but the proteins involved in rice urea metabolism have not yet been characterized. Coding sequences for rice arginase, urease, and the urease accessory proteins D (UreD), F (UreF), and G (UreG) involved in urease activation were identified and cloned. The functionality of urease and the urease accessory proteins was demonstrated by complementing corresponding Arabidopsis (Arabidopsis thaliana) mutants and by multiple transient coexpression of the rice proteins in Nicotiana benthamiana. Secondary structure models of rice (plant) UreD and UreF proteins revealed a possible functional conservation to bacterial orthologs, especially for UreF. Using amino-terminally StrepII-tagged urease accessory proteins, an interaction between rice UreD and urease could be shown. Prokaryotic and eukaryotic urease activation complexes seem conserved despite limited protein sequence conservation for UreF and UreD. In plant metabolism, urea is generated by the arginase reaction. Rice arginase was transiently expressed as a carboxyl-terminally StrepII-tagged fusion protein in N. benthamiana, purified, and biochemically characterized (K(m) = 67 mm, k(cat) = 490 s(-1)). The activity depended on the presence of manganese (K(d) = 1.3 microm). In physiological experiments, urease and arginase activities were not influenced by the external N source, but sole urea nutrition imbalanced the plant amino acid profile, leading to the accumulation of asparagine and glutamine in the roots. Our data indicate that reduced plant performance with urea as N source is not a direct result of insufficient urea metabolism but may in part be caused by an imbalance of N distribution.

Ureide catabolism in Arabidopsis thaliana and Escherichia coli.

The availability of whole genome sequences boosts the identification of biochemical pathways conserved across species using tools of comparative genomics. A cross-organism protein association analysis allowed us to identify two enzymes, ureidoglycine aminohydrolase and ureidoglycolate amidohydrolase, that catalyze the final reactions of purine degradation in the model plant Arabidopsis thaliana. A similar pathway was found in Escherichia coli, while an alternative metabolic route via ureidoglycine transaminase can be predicted for other organisms.

Identification, biochemical characterization, and subcellular localization of allantoate amidohydrolases from Arabidopsis and soybean.

Allantoate amidohydrolases (AAHs) hydrolize the ureide allantoate to ureidoglycolate, CO(2), and two molecules of ammonium. Allantoate degradation is required to recycle purine-ring nitrogen in all plants. Tropical legumes additionally transport fixed nitrogen via allantoin and allantoate into the shoot, where it serves as a general nitrogen source. AAHs from Arabidopsis (Arabidopsis thaliana; AtAAH) and from soybean (Glycine max; GmAAH) were cloned, expressed in planta as StrepII-tagged variants, and highly purified from leaf extracts. Both proteins form homodimers and release 2 mol ammonium/mol allantoate. Therefore, they can truly be classified as AAHs. The kinetic constants determined and the half-maximal activation by 2 to 3 microm manganese are consistent with allantoate being the in vivo substrate of manganese-loaded AAHs. The enzymes were strongly inhibited by micromolar concentrations of fluoride as well as by borate, and by millimolar concentrations of L-asparagine and L-aspartate but not D-asparagine. L-Asparagine likely functions as competitive inhibitor. An Ataah T-DNA mutant, unable to grow on allantoin as sole nitrogen source, is rescued by the expression of StrepII-tagged variants of AtAAH and GmAAH, demonstrating that both proteins are functional in vivo. Similarly, an allantoinase (aln) mutant is rescued by a tagged AtAln variant. Fluorescent fusion proteins of allantoinase and both AAHs localize to the endoplasmic reticulum after transient expression and in transgenic plants. These findings demonstrate that after the generation of allantoin in the peroxisome, plant purine degradation continues in the endoplasmic reticulum.