bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evidence for the existence of a body‐brain connection for skin moisturization
Authors: Wiechers Johann W. , Rawlings Anthony V. , Hansen Wei G. 
Published: September 2010

Maintenance of the right water levels in the skin is of crucial importance to maintain healthy, young‐looking skin. Moisturizing products have therefore aimed to influence the constitutive levels of natural moisturizer factor (NMF) and/or the formation of the skin lipid barrier. In humans, keratinocyte differentiation is influenced by sex hormones, in particular positively by estrogen and negatively by testosterone. It has been noted that postmenopausal women experience a decline in estrogen levels and a concomitant drop in skin moisturization. In our previous near‐infrared reflectance (NIR) spectroscopy work on human skin, we noted that skin moisturization was influenced by gender, age, psychological stress and lifestyle habits such as alcohol consumption and smoking. Many of these also affect the level of sex hormones. We therefore re‐evaluated NIR spectra from which we had already assessed the levels of skin moisturization in human volunteers to determine their levels of estrogen and testosterone non‐invasively. We subsequently built mathematical models to link skin moisture content to the levels of these sex hormones. In this way, we were able to establish the importance of sex hormones in skin moisturization. In men, skin moisturization levels are linked to their estrogen levels, whereas in females, skin moisturization levels are linked to both estrogen and testosterone concentrations. From the medical literature, it is known that smoking is associated with increased testosterone and reduced estrogen levels, which suggests that people that smoke are characterized by less hydrated skin as well as by increased testosterone levels. On the other hand, pregnant females that have significantly elevated estrogen to progesterone ratios, i.e. their increase in estrogen level exceeds their increase in testosterone levels, also often remark that their skin is well hydrated, confirming the link between sex hormone levels and skin moisturization. For them, we found a good correlation coefficient for skin moisturization levels and their estrogen to testosterone ratio.This work does not, however, answer question of a cause‐and‐effect relationship between the two. Increased levels of estrogen can either directly increase skin moisture levels or do so via a positive effect on skin barrier formation. It does, however, reveal once again the existence of a connection between our body (the skin) and our brain. Synthesis of sex hormones is regulated via the pituitary gland in our brain and it can therefore be argued that skin moisturization is directly or indirectly regulated via our brain. As many other factors like smoking and alcohol consumption actually influence estrogen levels in our blood, the influence of our brain on maintaining a skin moisture homeostasis may actually be much more pronounced than hitherto assumed.
Change in optical properties of stratum corneum induced by protein carbonylation in vitro
Authors: Iwai I. , Ikuta K. , Murayama K. , Hirao T. 
Published: September 2010

SynopsisThe skin is the frontier against the external environment and continuously exposed to the environmental oxidative stress such as ultraviolet (UV) irradiation. Protein carbonyls are the major oxidative products of protein and may be introduced by reaction with aldehydes derived from lipid peroxide. Acrolein is one of the most reactive aldehydes generated during degradation of lipid peroxides and protein–acrolein adducts have been found in the oxidatively damaged lesion including UV‐damaged skin. Recent studies revealed that protein carbonyls are also detected in thin outermost layer of the skin, the stratum corneum (SC). However, the effect of protein carbonylation on the function of SC was still unclear. In this study, we treated the SC sheets of reconstructed human epidermis and porcine epidermis with acrolein in the experimental conditions to explore the influence of protein carbonylation on the SC. Human and porcine SC sheets treated with acrolein showed less transmission at visible light than untreated SC sheets. Attenuated total reflection‐infrared spectroscopy with curve fitting analysis of amide I region showed that acrolein induced alterations in protein secondary structure of the porcine SC sheets, which were accompanied by diminished fibrous keratin structure observed by transmission electron microscopy. These results show the possibility that carbonylation of the SC caused by environmental factors is one of factors altering the fibrous structure of keratin and decreasing the light transmission of SC, which changes the quality of the skin appearance.
Male pattern androgenetic alopecia in an Indian context: a perspective study
Authors: Sehgal VN , Kak R , Aggarwal A , Srivastava G , Rajput P 
Published: September 2010

AbstractBackground  Androgenetic alopecia (AGA) has received scant attention, despite it being a common entity that may result in significant psychosocial morbidity. There are some patients who do not fit into any of the proposed types. Moreover, there have been no published studies of pattern and prevalence of AGA in males in an Indian context. Hence, the present study was an attempt to classify AGA in males with the aim of producing a simple, effective and easily reproducible classification.Methods  In total, 150 male patients were clinically diagnosed as AGA. After obtaining informed consent from all patients, a detailed history/examination was carried out, including a hair pull test, a trichogram investigation and a biopsy. Classification of AGA was subsequently attempted across Norwood guidelines.Results  A gradual shift in the type of AGA from the earlier types (II and III) to more severe types (VI) with increasing age was significant. Twenty‐seven patients did not fit into specific patterns according to Hamilton and Norwood classifications. In addition, type ‘a’ variant was recorded in 20% of patients, clearly indicating limitations of the existing classifications.Conclusions  It was possible to classify 80% of the AGA, with II (28%) and III (15%) being the most common types of AGA. Twenty‐seven patients (18%) could not be classified as a significant finding. There was considerable overlap in types IV, V and VI in the Norwood classification with the ‘a’ variants further confusing the picture.
Neuroimmune mechanisms in patients with atopic dermatitis during chronic stress
Authors: Lonne‐Rahm SB , Rickberg H , El‐Nour H , Mårin P , Azmitia EC , Nordlind K 
Published: September 2010

AbstractObjective  To identify pathoaetiological neuroimmune mechanisms in patients with atopic dermatitis (AD) and chronic stress, focusing at nerve density, sensory neuropeptides, and the serotonergic system.Methods  Eleven patients with AD with histories of stress worsening were included. Biopsies from involved and non‐involved skin were processed for immunohistochemistry. Salivary cortisol test was done as a marker for chronic stress.Results  There were more acanthosis and fewer nerve fibres in epidermis and papillary dermis of involved compared with non‐involved skin. Whereas there was no significant change in the number of substance P and calcitonin gene‐related peptide–positive nerve fibres between the involved and non‐involved skin, there was an increase in the epidermal fraction of 5‐hydroxtrytamine 1A (5‐HT1A) receptor and serotonin transporter protein (SERT) immunoreactivity in the involved skin. The number of 5‐HT2AR, CD3‐positive cells, and SERT‐positive cells, most of them being CD3 positive, was increased in involved skin. There was an increase in mast cells in the involved skin, and these cells were often located close to the basement membrane. There was a strong tendency to a correlation between 5‐HT2AR positive cells in the papillary dermis of involved skin and low cortisol ratios, being an indicator of chronic stress.Conclusion  A changed innervation and modulation of the serotonergic system are indicated in chronic atopic eczema also during chronic stress.
Ryanodine receptors regulate arterial diameter and wall [Ca2+] in cerebral arteries of rat via Ca2+‐dependent K+ channels
Authors: Knot Harm J. , Standen Nicholas B. , Nelson Mark T. 
Published: September 2010

The effects of inhibitors of ryanodine‐sensitive calcium release (RyR) channels in the sarcoplasmic reticulum (SR) and Ca2+‐dependent potassium (KCa) channels on the membrane potential, intracellular [Ca2+], and diameters of small pressurized (60 mmHg) cerebral arteries (100‐200 μm) were studied using digital fluorescence video imaging of arterial diameter and wall [Ca2+], combined with microelectrode measurements of arterial membrane potential.
Ryanodine (10 μM), an inhibitor of RyR channels, depolarized by 9 mV, increased intracellular [Ca2+] by 46 nM and constricted pressurized (to 60 mmHg) arteries with myogenic tone by 44 μm (≈22 %). Iberiotoxin (100 nM), a blocker of KCa channels, under the same conditions, depolarized the arteries by 10 mV, increased arterial wall calcium by 51 nM, and constricted by 37 μm (≈19 %). The effects of ryanodine and iberiotoxin were not additive and were blocked by inhibitors of voltage‐dependent Ca2+ channels.
Caffeine (10 mM), an activator of RyR channels, transiently increased arterial wall [Ca2+] by 136 ± 9 nM in control arteries and by 158 ± 12 nM in the presence of iberiotoxin. Caffeine was relatively ineffective in the presence of ryanodine, increasing [calcium] by 18 ± 5 nM.
In the presence of blockers of voltage‐dependent Ca2+ channels (nimodipine, diltiazem), ryanodine and inhibitors of the SR calcium ATPase (thapsigargin, cyclopiazonic acid) were without effect on arterial wall [Ca2+] and diameter.
These results suggest that local Ca2+ release originating from RyR channels (Ca2+ sparks) in the SR of arterial smooth muscle regulates myogenic tone in cerebral arteries solely through activation of KCa channels, which regulate membrane potential through tonic hyperpolarization, thus limiting Ca2+ entry through L‐type voltage‐dependent Ca2+ channels. KCa channels therefore act as a negative feedback control element regulating arterial diameter through a reduction in global intracellular free [Ca2+].
Convergence properties of solitary tract neurones driven synaptically by cardiac vagal afferents in the mouse
Authors: Paton Julian F. R. 
Published: September 2010

Cardiac vagal receptors are chemically and/or mechanically sensitive but it is unknown if this information is preserved centrally within the nucleus of the solitary tract (NTS). The present study had two aims: first, to investigate qualitatively whether both mechanically and chemically sensitive cardiac vagal encoding were preserved within the NTS, and second, to determine the patterns of convergence from other cardiorespiratory afferents to NTS neurones receiving cardiac vagal inputs.
The extracellular activity of single NTS neurones was investigated during stimulation of both chemically and mechanically sensitive cardiac vagal receptors in a working heart‐brainstem preparation of mouse. Chemically sensitive cardiac receptors were stimulated using intra‐left ventricular injections of either veratridine (1‐3 μg kg−1), bradykinin (0.25‐1 μg) or prostaglandin E2 (100‐200 ng), whereas the left ventricle was distended to activate cardiac mechanoreceptors.
Forty‐three NTS neurones were activated both synaptically by electrical stimulation of the ipsilateral vagus nerve (latency, 35 ± 3 ms), and by intra‐left ventricular injection of veratridine and also, in some cases, by bradykinin and/or PGE2. These NTS neurones were delineated into two populations based on their response to left ventricular distension and convergence properties. Left ventricular distension‐insensitive neurones (n= 30) were excited by stimulation of carotid body chemoreceptors (81 %) but not arterial baroreceptors (3 %; i.e. n= 1 neurone), whereas distension‐sensitive cells (n= 13) were activated mainly by baroreceptors (86 %) rather than peripheral chemoreceptors (14 %; i.e. n= 1 neurone).
The data reveal two distinct populations of NTS neurones receiving cardiac vagal inputs: (a) cells responsive to veratridine stimulation only, and (b) neurones activated by both veratridine and mechanical stimuli. The specific convergence pattern of baroreceptors and chemoreceptors to these cardioreceptive NTS neurones is discussed in relation to a common afferent modality integration within the NTS.
Excursion is important in regulating sarcomere number in the growing rabbit tibialis anterior
Authors: Koh Timothy J. , Herzog Walter 
Published: September 2010

The mechanical signal(s) that may be important in regulating the number of sarcomeres in series in skeletal muscle fibres or fascicles (sarcomere number) remain(s) speculative, in part because the in vivo mechanical environment of muscle has not yet been defined during sarcomere number perturbations. In the present study, measurements of the in vivo mechanical environment were used to test the hypothesis that increasing muscle excursion results in increased serial sarcomere addition in growing animals.
The tibialis anterior (TA) was released from its retinacular restraint at the ankle joint to increase muscle excursion in 4‐week‐old female New Zealand White rabbits. Twelve weeks post release, muscle excursion and sarcomere number were significantly increased for released TAs compared with control TAs.
General cage activity over a 24 h period and in vivo ankle joint kinematics of the experimental leg during hopping on a treadmill were not significantly different between control and release groups, suggesting that altered animal and joint activity patterns were not responsible for the increased serial sarcomere addition associated with TA release.
In vivo TA forces during hopping and during a large force‐producing foot‐flicking motion were significantly decreased in released TAs compared with control TAs. Chronically decreased force production may have been involved in the decreased longitudinal tendon growth observed for the released TA compared with the control TA, which, in turn, may have stimulated the increase in serial sarcomere addition. However, increasing force production of the released TA by partial ablation of the extensor digitorum longus did not inhibit the increase in serial sarcomere addition.
The results of this study support the hypothesis that increasing excursion results in increased serial sarcomere addition in growing animals and, when combined with the results of previous studies indicating that decreasing excursion results in decreased serial sarcomere addition, support the working hypothesis that excursion is important in regulating sarcomere number in growing animals.
COMPARISON – ITS SCOPE AND LIMITS
Authors: BRADSHAW A. D. 
Published: September 2010

SummaryAt any point in time, any discipline in science tends to be seized by a particular methodology or enthusiasm and other approaches get ‘dumped’. So it is in ecology‐ although, because of obstinate individualism, nothing is ever completely forgotten. We are currently in a reductionist, population‐dominated era. Twenty‐five years ago, our interests lay primarily in comparisons of species. In between, the holistic approach has had a good run with studies of ecosystems everywhere. This introductory paper reflects on this history and particularly, because of the occasion, examines the value of the process of comparison.
Tonic and Phasic Electrodermal Measures of Human Aversive Conditioning with Long Duration Stimuli
Authors: Lovibond Peter F. 
Published: September 2010

ABSTRACTTwo experiments investigated phasic and tonic electrodermal responding to long, variable‐duration stimuli in aversive conditioning procedures. Experiment 1 demonstrated reliable differential conditioning on both phasic (first interval response, FIR) and tonic (change in skin conductance level, δSCL; spontaneous fluctuations) measures, using 10–40‐s slides as conditioned stimuli (CSs) and electric shock as the unconditioned stimulus (UCS). Experiment 2 examined the sensitivity of phasic and tonic measures to UCS aversiveness. Both FIR and δSCL were greater to a conditioned stimulus paired with shock than one paired with an innocuous reaction‐time warning tone. Responding was reversed when the reinforcement contingencies were reversed. It was suggested that, with long duration CSs and an aversive UCS, phasic measures to stimulus onset, such as FIR, may reflect both stimulus significance and threat appraisal, whereas tonic measures reflect primarily arousal or anxiety arising from anticipation of the aversive unconditioned stimulus.
Fearfulness and Startle Potentiation during Aversive Visual Stimuli
Authors: Cook Edwin W. , Davis Tammy L. , Hawk Larry W. , Spence Ellen L. , Gautier Clara H. 
Published: September 2010

ABSTRACTRecent experimental research suggests an association between negative affect and potentiation of the human startle reflex, as well as enhancement of this effect among fearful compared to low fear subjects. In the present study, 32 undergraduates were selected for high or low total Fear Survey Schedule scores. Acoustic startle probes were presented while subjects received warned presentations of aversive and neutral photographic slides. High fear but not low fear subjects showed potentiated short‐latency cardiac acceleration and blink magnitude, and reduced blink latency, during aversive compared to neutral slides. These results support the hypothesis that affective modulation of startle is enhanced among high fear compared to low fear subjects. Considered in the context of prior findings, the results suggest that this individual difference effect generalizes across psychophysiological components of the startle reflex and diverse procedures for manipulating affect.
Effects of aging on event‐related brain potentials and reaction times in an auditory oddball task
Authors: IRAGUI VICENTE J. , KUTAS MARTA , MITCHINER MARK R. , HILLYARD STEVEN A. 
Published: September 2010

AbstractAuditory event‐related potentials (ERPs) were recorded from 71 healthy individuals between 18 and 82 years of age during performance of a disjunctive reaction time task in an auditory oddball paradigm. The effects of aging on reaction times and on the latencies, amplitudes, and distributions of each of the main ERP components were examined. No significant slowing of the reaction times of the elderly subjects was observed in relation to the younger ones. The peak latencies of both the N1 and P2 components elicited by standard tones were slightly but significantly slowed with age. In the ERPs of target tones, the later, endogenous components (N2, P3, and SW) showed linear increases in latency as a function of age; the later the component, the longer the age‐related delay. In general, aging was associated with less negativity (both N2 and SW) and more positivity (P3) over the anterior scalp, together with a smaller P3 and a more pronounced N2 over posterior scalp areas. Most of the effects observed in target ERPs were also evident in the difference waves derived from subtraction of the standard from the target ERPs, although the slope of the age‐related latency increase of N2 was shallower and that of the P3 was steeper in the difference ERPs. These findings are discussed in relation to previous accounts of ERP changes with aging.
Regional cerebral blood flow during experimental phobic fear
Authors: FREDRIKSON MATS , WIK GUSTAV , GREITZ TORGNY , ERIKSSON LARS , STONE‐ELANDER SHARON , ERICSON KAJ , SEDVALL GÖRAN 
Published: September 2010

AbstractPositron emission tomographic measurements of regional cerebral blood flow (rCBF) were used to investigate central nervous system correlates of fear and anxiety. Volunteers with symptomatic snake phobia were studied while exposed to visual phobogenic, aversive, and neutral stimuli. Anxiety ratings and the number of nonspecific electrodermal fluctuations increased as a function of phobic stimulation. Phobic, compared to neutral and aversive, stimulation elevated rCBF in the visual associative cortex. The basal ganglia were not activated more by phobic than aversive or neutral stimulation. However, cortical and thalamic rCBF were always correlated during phobic but not aversive or neutral stimulation. This indicates that the thalamus could be a relay station for phobic stimulus processing and affect.
Affective modulation of brain potentials to painful and nonpainful stimuli
Authors: Kenntner‐Mabiala Ramona , Pauli Paul 
Published: September 2010

AbstractIn accordance with the emotional priming hypothesis, emotions seem to modulate pain perception and pain tolerance thresholds. To further evaluate this association, event‐related brain potentials (ERPs) elicited by painful and nonpainful electrical stimuli during processing of positive, neutral, and negative valenced pictures were recorded from 30 healthy volunteers. Valence of pictures affected pain ratings and the N150 elicited by painful stimuli, with lowest amplitudes for positive pictures and highest amplitudes for negative pictures. The P260 elicited by painful and nonpainful stimuli was modulated by arousal with reduced amplitudes with arousing (positive or negative) compared to neutral pictures. N150 amplitudes varying with picture valence seem to reflect an affective modulation of pain perception whereas P260 amplitudes varying with picture arousal rather reflect non‐pain‐specific attentional processes.
The Relation between the Duty Cycle and Anesthetic Effect in Lidocaine Iontophoresis Using Alternating Current
Authors: Wakita Ryo , Nakajima Atsushi , Haida Yu , Umino Masahiro , Fukayama Haruhisa 
Published: September 2010

AbstractWe assessed the effect of the duty cycle on the anesthetic effect during lidocaine alternating current (AC) iontophoresis. A solution of 2% lidocaine was delivered to the medial antecubital skin for 20 minutes using AC iontophoresis with a duty cycle of 60%, 70%, or 80%. The von Frey test was then performed to evaluate the anesthetic effect. In the groups treated with a duty cycle of 80% or 70% the touch thresholds (TT) were significantly elevated from 0 minutes to 30 minutes and from 0 minutes to 20 minutes. TT were significantly elevated at 0 minutes in the group treated with a 60% duty cycle. The anesthetic effect was significantly enhanced in a duty cycle‐dependent manner.
Long‐Term Return Reversals: Overreaction or Taxes?
Authors: GEORGE THOMAS J. , HWANG CHUAN‐YANG 
Published: September 2010

ABSTRACTLong‐term reversals in U.S. stock returns are better explained as the rational reactions of investors to locked‐in capital gains than an irrational overreaction to news. Predictors of returns based on the overreaction hypothesis have no power, while those that measure locked‐in capital gains do, completely subsuming past returns measures that are traditionally used to predict long‐term returns. In data from Hong Kong, where investment income is not taxed, reversals are nonexistent, and returns are not forecastable either by traditional measures or by measures based on the capital gains lock‐in hypothesis that successfully predict U.S. returns.
Is the Corporate Loan Market Globally Integrated? A Pricing Puzzle
Authors: CAREY MARK , NINI GREG 
Published: September 2010

ABSTRACTWe offer evidence that interest rate spreads on syndicated loans to corporate borrowers are economically significantly smaller in Europe than in the United States, other things equal. Differences in borrower, loan, and lender characteristics do not appear to explain this phenomenon. Borrowers overwhelmingly issue in their natural home market and bank portfolios display home bias. This may explain why pricing discrepancies are not competed away, though their causes remain a puzzle. Thus, important determinants of loan origination market outcomes remain to be identified, home bias appears to be material for pricing, and corporate financing costs differ across Europe and the United States.