412 research outputs found
Fifty-kDa Hyaluronic Acid Upregulates Some Epidermal Genes without Changing TNF-α Expression in Reconstituted Epidermis
Background: Due to its strong water binding potential, hyaluronic acid (HA) is a well-known active ingredient for cosmetic applications. However, based on its varying molecular size, skin penetration of HA may be limited. Recent studies have demonstrated that low-molecular-weight HA (LMW HA) may show a certain proinflammatory activity. We thus aimed to characterize an LMW-sized HA molecule that combines strong anti-aging abilities with efficient skin penetration but lacks potential proinflammatory effects. Methods: Total RNA and total protein were isolated from reconstituted human epidermis following incubation with HAs of various molecular weights (20, 50, 130, 300, 800 and 1,500 kDa). Tumor necrosis factor-alpha expression was determined using quantitative PCR. Genonnic and proteomic expression of various junctional proteins was determined using Affymetrix and common Western blotting techniques. Results: LMW HA of approximately 50 kDa did not significantly alter tumor necrosis factor-alpha expression compared to 20-kDa HA, but revealed significantly higher skin penetration rates than larger sized HA associated with increased expression of genes and proteins known to be involved in tight junction formation and keratinocyte cohesion. Conclusion: LMW HA of approximately 50 kDa shows better penetration abilities than larger-sized HA. In addition, LMW HA influences the expression of various genes including those contributing to keratinocyte differentiation and formation of intercellular tight junction complexes without showing proinflammatory activity. These observations contribute to current knowledge on the effects of LMW HA on keratinocyte biology and cutaneous physiology. Copyright (C) 2011 S. Karger AG, Base
Working Memory in Attention Deficit/Hyperactivity Disorder is Characterized by a Lack of Specialization of Brain Function
Working memory impairments are frequent in Attention Deficit/Hyperactivity Disorder (ADHD) and create problems along numerous functional dimensions. The present study utilized the Visual Serial Addition Task (VSAT) and functional magnetic resonance imaging (fMRI) to explore working memory processes in thirteen typically developing (TD) control and thirteen children with ADHD, Combined type. Analysis of Variance (ANOVA) was used to examine both main effects and interactions. Working memory-specific activity was found in TD children in the bilateral prefrontal cortex. In contrast the within-group map in ADHD did not reveal any working-memory specific regions. Main effects of condition suggested that the right middle frontal gyrus (BA6) and the right precuneus were engaged by both groups during working memory processing. Group differences were driven by significantly greater, non-working memory-specific, activation in the ADHD relative to TD group in the bilateral insula extending into basal ganglia and the medial prefrontal cortex. A region of interest analysis revealed a region in left middle frontal gyrus that was more active during working memory in TD controls. Thus, only the TD group appeared to display working memory-modulated brain activation. In conclusion, children with ADHD demonstrated reduced working memory task specific brain activation in comparison to their peers. These data suggest inefficiency in functional recruitment by individuals with ADHD represented by a poor match between task demands and appropriate levels of brain activity
Additive Polynomials for Finite Groups of Lie Type
This paper provides a realization of all classical and most exceptional
finite groups of Lie type as Galois groups over function fields over F_q and
derives explicit additive polynomials for the extensions. Our unified approach
is based on results of Matzat which give bounds for Galois groups of Frobenius
modules and uses the structure and representation theory of the corresponding
connected linear algebraic groups.Comment: 59 pages; v2: added reference, slightly restructured section 6.1, few
small rewordings; v3: completed realization of Steinberg's triality groups
(thanks to P. Mueller for solving the remaining open question); clarified
argument how to use Thm. 3.
Mind Perception Is the Essence of Morality
Mind perception entails ascribing mental capacities to other entities, whereas moral judgment entails labeling entities as good or bad or actions as right or wrong. We suggest that mind perception is the essence of moral judgment. In particular, we suggest that moral judgment is rooted in a cognitive template of two perceived mindsâa moral dyad of an intentional agent and a suffering moral patient. Diverse lines of research support dyadic morality. First, perceptions of mind are linked to moral judgments: dimensions of mind perception (agency and experience) map onto moral types (agents and patients), and deficits of mind perception correspond to difficulties with moral judgment. Second, not only are moral judgments sensitive to perceived agency and experience, but all moral transgressions are fundamentally understood as agency plus experienced sufferingâthat is, interpersonal harmâeven ostensibly harmless acts such as purity violations. Third, dyadic morality uniquely accounts for the phenomena of dyadic completion (seeing agents in response to patients, and vice versa), and moral typecasting (characterizing others as either moral agents or moral patients). Discussion also explores how mind perception can unify morality across explanatory levels, how a dyadic template of morality may be developmentally acquired, and future directions
Is spoken language all-or-nothing? Implications for future speech-based human-machine interaction
Recent years have seen significant market penetration for voice-based personal assistants such as Appleâs Siri. However, despite this success, user take-up is frustratingly low. This article argues that there is a habitability gap caused by the inevitablemismatch between the capabilities and expectations of human users and the features and benefits provided by contemporary technology. Suggestions aremade as to how such problems might be mitigated, but a more worrisome question emerges: âis spoken language all-or-nothingâ? The answer, based on contemporary views on the special nature of (spoken) language, is that there may indeed be a fundamental limit to the interaction that can take place between mismatched interlocutors (such as humans and machines). However, it is concluded that interactions between native and non-native speakers, or between adults and children, or even between humans and dogs, might provide critical inspiration for the design of future speech-based human-machine interaction
ZnO Nanorods via Spray Deposition of Solutions Containing Zinc Chloride and Thiocarbamide
In this work we present the results on formation of ZnO nanorods prepared by spray of aqueous solutions containing ZnCl2and thiocarbamide (tu) at different molar ratios. It has been observed that addition of thiocarbamide into the spray solution has great impact on the size, shape and phase composition of the ZnO crystals. Obtained layers were characterized by scanning electron microscopy (SEM) equipped with energy selected backscattered electron detection system (ESB), X-ray diffraction (XRD) and photoluminescence spectroscopy (PL). Small addition of thiocarbamide into ZnCl2solution (ZnCl2:tu = 1:0.25) supports development of significantly thinner ZnO nanorods with higher aspect ratio compared to those obtained from ZnCl2solution. Diameter of ZnO rods decreases from 270 to 100 nm and aspect ratio increases from âŒ2.5 to 12 spraying ZnCl2and ZnCl2:tu solutions, respectively. According to XRD, well crystallized (002) orientated pure wurtzite ZnO crystals have been formed. However, tiny âspotââlike formations of ZnS were detected on the side planes of hexagonal rods prepared from the thiocarbamide containing solutions. Being adsorbed on the side facets of the crystals ZnS inhibits width growth and promotes longitudinalc-axis growth
Angiotensin II receptor expression and relation to Helicobacter pylori-infection in the stomach of the Mongolian gerbil
<p>Abstract</p> <p>Background</p> <p>The role of the renin-angiotensin system in gastric physiology and disease has as yet been sparsely explored. The first aim of the study was to investigate the baseline presence and location of angiotensin II receptors (AT1R and AT2R) in the stomach of the Mongolian gerbil. A second aim was to elucidate whether the presence of <it>H. pylori </it>infection is associated with changes in the expression of these receptors.</p> <p>Methods</p> <p><it>H. pylori</it>-negative and <it>H. pylori-</it>infected (strain SS1 or TN2GF4) male Mongolian gerbils were investigated. The stomachs were examined at six or 12 months after inoculation by the use of immunohistochemistry, western blot and microscopic morphometry.</p> <p>Results</p> <p>AT1R and AT2R were located in a variety of cells in the gerbil gastric wall, including a subpopulation of endocrine cells in the antral mucosa and inflammatory cells infiltrating <it>H. pylori</it>-infected stomachs. Gerbils infected with the SS1 strain showed a significantly increased antral AT1R protein expression and an increased number of infiltrating polymorphonuclear leucocytes (PMNs) at 12 months. The AT1R protein expression correlated with the number of PMNs and the antral expression of myeloperoxidase.</p> <p>Conclusions</p> <p>Angiotensin II receptors are present in a variety of cells in the gastric wall of the Mongolian gerbil. The results indicate an influence dependent on the <it>H. pylori </it>strain on the gastric AT1R expression and a relationship between gastric AT1R expression and mucosal PMNs infiltration.</p
Tolerability of inhaled N-chlorotaurine in the pig model
<p>Abstract</p> <p>Background</p> <p>N-chlorotaurine, a long-lived oxidant produced by human leukocytes, can be applied in human medicine as an endogenous antiseptic. Its antimicrobial activity can be enhanced by ammonium chloride. This study was designed to evaluate the tolerability of inhaled N-chlorotaurine (NCT) in the pig model.</p> <p>Methods</p> <p>Anesthetized pigs inhaled test solutions of 1% (55 mM) NCT (n = 7), 5% NCT (n = 6), or 1% NCT plus 1% ammonium chloride (NH<sub>4</sub>Cl) (n = 6), and 0.9% saline solution as a control (n = 7), respectively. Applications with 5 ml each were performed hourly within four hours. Lung function, haemodynamics, and pharmacokinetics were monitored. Bronchial lavage samples for captive bubble surfactometry and lung samples for histology and electron microscopy were removed.</p> <p>Results</p> <p>Arterial pressure of oxygen (PaO<sub>2</sub>) decreased significantly over the observation period of 4 hours in all animals. Compared to saline, 1% NCT + 1% NH<sub>4</sub>Cl led to significantly lower PaO<sub>2 </sub>values at the endpoint after 4 hours (62 ± 9.6 mmHg vs. 76 ± 9.2 mmHg, p = 0.014) with a corresponding increase in alveolo-arterial difference of oxygen partial pressure (AaDO<sub>2</sub>) (p = 0.004). Interestingly, AaDO<sub>2 </sub>was lowest with 1% NCT, even lower than with saline (p = 0.016). The increase of pulmonary artery pressure (PAP) over the observation period was smallest with 1% NCT without difference to controls (p = 0.91), and higher with 5% NCT (p = 0.02), and NCT + NH<sub>4</sub>Cl (p = 0.05).</p> <p>Histological and ultrastructural investigations revealed no differences between the test and control groups. The surfactant function remained intact. There was no systemic resorption of NCT detectable, and its local inactivation took place within 30 min. The concentration of NCT tolerated by A549 lung epithelial cells <it>in vitro </it>was similar to that known from other body cells (0.25â0.5 mM).</p> <p>Conclusion</p> <p>The endogenous antiseptic NCT was well tolerated at a concentration of 1% upon inhalation in the pig model. Addition of ammonium chloride in high concentration provokes a statistically significant impact on blood oxygenation.</p
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