bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional connectivity between somatosensory and visual cortex in early blind humans
Authors: Wittenberg George F. , Werhahn Konrad J. , Wassermann Eric M. , Herscovitch Peter , Cohen Leonardo G. 
Published: September 2004

AbstractCrossmodal plasticity occurs when loss of input in one sensory modality leads to reorganization in brain representations of other sensory modalities. In congenital blindness the visual cortex becomes responsive to somatosensory input such as occurs during Braille reading. The route by which somatosensory information reaches the visual cortex is not known. Here, we used repetitive transcranial magnetic stimulation (rTMS) to probe the connection between primary somatosensory cortex (S1) and early visual cortex (V1 and neighboring areas), combining rTMS with positron emission tomography (PET). We applied stimulation over S1 in sighted, early blind and late blind individuals. Baseline regional cerebral blood flow in occipital cortex was highest in early blind and lowest in late blind individuals. Only the early blind group showed significant activation of early visual areas when rTMS was delivered over S1. This activation was significantly higher in early than in late blind, but not relative to sighted controls. These results are consistent with the hypothesis that tactile information may reach early visual areas in early blind humans through cortico‐cortical pathways, possibly supporting enhanced tactile information processing.
Lack of α‐synuclein does not alter apoptosis of neonatal catecholaminergic neurons
Authors: Stefanis Leonidas , Wang Qiaohong , Oo Tinmarla , Lang‐Rollin Isabelle , Burke Robert E. , Dauer William T. 
Published: September 2004

Abstractα‐Synuclein is an abundant neuronal protein of uncertain function linked to Parkinson's disease. Numerous studies have proposed an antiapoptotic function for α‐synuclein, based on overexpression experiments in cell lines. To explore whether α‐synuclein has such a physiological function, we assessed the response of wild type or α‐synuclein null neonatal mouse sympathetic neurons to nerve growth factor deprivation, a well‐characterized stimulus of neuronal apoptosis. There was no difference in the rate of neuronal loss, neuronal apoptosis, or c‐jun phosphorylation. Furthermore, the absence of α‐synuclein did not alter the magnitude of naturally occurring cell deathin vivoin substantia nigra pars compacta. Therefore, α‐synuclein is unlikely to play a significant role in apoptotic signalling in catecholaminergic neurons of the neonatal nervous system.
Changes in expression of PACAP in rat sensory neurons in response to sciatic nerve compression
Authors: Pettersson L. M. E. , Dahlin L. B. , Danielsen N. 
Published: September 2004

AbstractIn the present study, expression of pituitary adenylate cyclase‐activating polypeptide (PACAP) in rat dorsal root ganglion (DRG) neurons and sciatic nerve following experimental sciatic nerve compression was studied with the use of quantitative immunohistochemistry and in situ hybridization. Previously, we have investigated changes in PACAP expression after nerve transection and, here, the far more frequently encountered condition of nerve compression injury is examined. Nerve compression was performed unilaterally on the rat sciatic nerve, at mid‐thigh level, by application of a narrow silicone tube around the nerve for 3, 7, 14 or 28 days, respectively. We detect a statistically significant upregulation in the number and density of PACAP mRNA expression in both small and large DRG neurons in response to nerve compression. An increased number of PACAP‐immunoreactive neurons is also found in the ipsilateral DRG. In addition, PACAP immunoreactivity is observed in the compressed sciatic nerve segment and adjacent nerve tissue after nerve compression. The present findings can be compared with previous studies where we have shown that PACAP expression is upregulated in DRG; in response to peripheral inflammation (primarily in small–medium neurons), and after axotomy (dramatic upregulation in medium–large neurons). In view of the recent findings of an increased PACAP expression in DRG after nerve compression, as well as the previous findings of a modulation of PACAP expression in response to axotomy and inflammation, it is likely that PACAP is also involved in the modulation of the response to peripheral nerve compression.
NxfandFbxo33: novel seizure‐responsive genes in mice
Authors: Flood Warren D. , Moyer Robert W. , Tsykin Anna , Sutherland Grant R. , Koblar Simon A. 
Published: September 2004

AbstractMuch is understood about the response of the brain to seizure but little is known in relation to the underlying molecular mechanisms involved. We used microarray technology to investigate the complex genetic response of the brain to generalized seizure. For this investigation a seizure‐specific mouse brain cDNA library was generated and spotted onto microarray slides with the aim of increasing the likelihood of identifying novel genes responsive to seizure. Microarray analysis was performed on mouse hippocampus 1 h after generalized seizure pharmacologically induced by pentylenetetrazol (PTZ). Using the custom microarray slides, six genes were identified as being up‐regulated in this seizure model and results were validated by real‐time PCR. Four of the seizure‐responsive genes had previously‐reported roles in apoptosis, proliferation or differentiation of neural cells. Two of the genes were novel andin situhybridization analysis demonstrated heightened mRNA expression in the hippocampus 1 h following generalized convulsive seizure, in a pattern which is typical for other activity‐dependant genes expressed in this structure. In addition to being up‐regulated postseizure, the genes described in this paper appear to be expressed normally in the adult hippocampus and during development.
Magnetic resonance imaging reveals neuronal degeneration in the brainstem of the superoxide dismutase 1G93A G1H transgenic mouse model of amyotrophic lateral sclerosis
Authors: Zang Da Wei , Yang Qing , Wang Hong Xin , Egan Gary , Lopes Elizabeth C , Cheema Surindar S 
Published: September 2004

AbstractMagnetic resonance imaging (MRI) is becoming the preferred neuroimaging modality for the diagnosis of human amyotrophic lateral sclerosis (ALS). A useful animal model of ALS is the superoxide dismutase 1G93A G1H transgenic mouse, which shows many of the clinico‐pathological features of the human condition. We have employed a 4.7‐Tesla MRI instrument to determine whether a noninvasive imaging approach can reveal pathological changes in the nervous system of this animal model. Our T2‐weighted MRI revealed consistent changes in brain and brainstem of these mice. Hyperintensities, indicative of neuropathology, were observed in several areas including the nucleus ambiguus, facial nucleus, trigeminal motor nucleus, rostroventrolateral reticular nucleus, lateral paragigantocellular nucleus and the substantia nigra. Histology analysis including neuronal counts of the imaged brains confirmed the T2‐weighted MRI findings. Enlarged ventricles and hypointense striations, indicative of global atrophy, were also observed in the brain and cerebellum. This atrophy was confirmed by fresh brain weight data. The extensive global degeneration involving multiple structures suggests a multisystem disease that is similar to human ALS.
A multi‐sample design for assessing the comedolytic activity of topical products
Authors: Knaggs H. , Santanastasio H. , Bowman J. , Pagnoni A. 
Published: September 2004

SynopsisBackground:  Facial comedolytic studies allow testing of a maximum of two products. The upper back provides a larger area with a more uniform distribution of microcomedones for comedolytic studies.Objective:  To design a multi‐sample method for assessing comedolytic activity of topical products on the back. The effect of season on product discrimination was also explored.Methods:  Three cleansing formulations (products B, C and D), a negative water control and 0.025% Retin‐A® cream (positive control) were tested. Seven subjects were recruited in summer and nine in fall. Products were applied for 8 weeks, comedolysis was assessed by visually evaluating cyanoacrylate follicular biopsies taken at baseline and post‐treatment.Results:  In all data sets (summer, fall and combined), sites treated with Retin‐A® had a significantly lower number of microcomedones as compared to the negative water control. In addition, cleansers B and D showed a significant reduction from baseline in the fall and combined (summer and fall) data, but not in summer data alone indicating different responses to treatment during the year.Conclusions:  The design was sensitive enough to detect differences between cleansing formulations under normal washing conditions. Reduced sensitivity observed during summer suggests hot humid conditions may decrease the comedolytic performance of topical products.
The penetration enhancement and the lipolytic effects of TAT–GKH, both in in vitro, ex vivo, and in vivo
Authors: Lim J. , Chang M. , Park S. , Kang N. , Song Y. , Kang Y.‐S. , Cho W.‐G. 
Published: September 2004

It was demonstrated that the trans‐activating transcriptional activator (TAT) protein from HIV‐1 could enter cells when added to the surrounding media. TAT peptide chemically attached to various proteins was able to deliver these proteins to various cells and even at high levels in heart and spleen tissues in mice. In this study, the tri‐peptide GKH (glycine–lysine–histidine) derived from the parathyroid hormone, which is known as a lipolytic peptide, was attached to 9‐poly lysine (TAT) to be used as a cosmetic ingredient for eye‐bag care product. When glycerol is released, expressed as the extracellular glycerol concentration (the so‐called lipolysis index), TAT–GKH at 10−5m induces a maximal lipolytic effect of approximately 41.5% in epididymal adipocytes isolated from rats, compared with basal lipolysis. In a microdialysis study, TAT–GKH was perfused into epididymal adipose tissues of anaesthetized rats in increasing concentrations in a Ringer solution. The glycerol concentration in each dialysate was measured using an ultra‐sensitive radiometric method. The perfusion of TAT–GKH induced a lipolytic effect. A penetration study showed that TAT–GKH resulted in a sevenfold higher penetration into excised hairless mice skin than GKH. An in vivo study showed that a TAT–GKH containing emulsion had a better effect upon the relative volume reduction of eye bag after 28 days of application on 22 healthy female volunteers than the placebo.It was therefore concluded that TAT–GKH increased skin penetration, which resulted in enhanced lipolytic effects in in vitro, ex vivo and in volume reduction of eye‐bags in in vivo studies.
Comparison of the biomechanical and biosynthetic behavior of normal human fibroblasts and fibroblasts from a forehead wrinkle
Authors: Jouandeaud M. , Viennet C. , Bordes S. , Closs B. , Humbert P. 
Published: September 2004

Wrinkles are the most obvious expression of skin aging and are manifested by numerous changes in the organization and structure of the dermis. To better understand if this tissue modification could be linked to a modification of cell function, contractile and synthesis capacities of normal aged human fibroblasts and those obtained from a biopsy of a forehead wrinkle were studied and compared. The capacity of fibroblasts to adhere to the collagen network and to maintain a three‐dimensional structure of the dermis was studied using a three‐dimensional model of a collagen gel. The metabolic activity of both cell types was determined immunochemically by quantifying collagen I synthesis. Human fibroblasts from the wrinkle contracted the collagen gel less than normal aged human fibroblasts and synthesized less collagen I. The results show that the metabolic activity of aging fibroblasts decelerates and that aging fibroblasts lose their capacity to adhere to collagen fibers, thus limiting the possibility of organizing dermal tissue.The potential of an active ingredient to compensate for the reduction of metabolic activity and to restore the contractile capacity of fibroblasts from the wrinkle was investigated. This effect was compared with a reference molecule, vitamin C.
Investigating the relationship between the hair fiber proteome and hair quality
Authors: Heywood D.M. , Vrettou C. , Wood J. , Hill J. , Casey S. , Cornwell P.A. 
Published: September 2004

Many hair characteristics (e.g. color and curl) are genetically determined. Here, we investigated whether hair quality is also genetically controlled and related to differences in hair composition. Female, Caucasian subjects (n = 292) were recruited into this study and segmented by self‐perceived hair quality and by permanent colorant usage. Hair fibers were collected and characterized by amino acid analysis, dry tensile elastic modulus testing and two‐dimensional electrophoresis of hair protein extracts.Protein analysis revealed a string of 66 kDa proteins that correlated with hair of high quality. Loss of low molecular weight (14–29 kDa) proteins increased with colorant usage, particularly in hair of low quality. Amino acid analysis showed that the levels of serine and threonine across all the subjects followed bimodal frequency distributions suggestive of a genetic influence. Overall, data suggested that perception of quality was linked to high serine and threonine levels. In addition, where hair was colored, quality was associated with lower cysteic acid levels. Lower cysteic acid levels were not linked to lower colorant usage and our data suggest that high quality hair may be more resistant to colorant damage. Elastic modulus was significantly higher in hair of higher quality (4.65 GPa) compared to all medium and low quality hair combined (4.3 GPa), P < 0.02. This suggests a link between altered hair composition and mechanical properties. In conclusion, the composition and mechanical properties of hair have been linked to hair quality. We hypothesize that hair quality is thus likely to be genetically determined. Understanding of the links between hair composition and its properties could be utilized in the future for designing products targeted to each individual's hair make‐up, and for producing diagnostic tools for determining hair quality.
Improving cellular function through modulation of energy metabolism
Authors: Maes D. , Collins D. , Declercq L. , Foyouzi‐Yousseffi R. , Gan D. , Mammone T. , Pelle E. , Marenus K. , Gedeon H. 
Published: September 2004

The ambivalent consequences of mitochondrial stimulation on cellular activity have been well established. Mitochondria supply the cell with energy through a process of oxidative phosphorylation but thereby generate free radicals, resulting in the accumulation of hydrogen peroxide in the cytoplasm. We have investigated the impact of cellular senescence as well as UV irradiation, on the balance between these two activities.The adenosine triphosphate (ATP) level, DNA and protein synthesis in fibroblasts obtained from donors between 30 and 90 years of age appeared to be significantly influenced by the aging process. Both DNA and protein synthesis could be stimulated by increasing intracellular ATP levels. In‐vitro senescent fibroblasts showed a reduction in the level of ATP as well as a shift in mitochondrial membrane potential. At the same time, there was an increase in intracellular hydrogen peroxide with increasing population doubling, indicating a clear dysfunction of the metabolic machinery in the mitochondria of senescent cells. To counteract this degradation of the energy pool, we treated cells with creatine, which is known to restore the pool of phosphocreatine in the mitochondria. Creatine treatment significantly increased cell survival after UV exposure, stimulated the repair of UVB‐induced DNA damage in keratinocytes and caused a significant reduction in the number of sunburn cells in a UVB‐exposed reconstituted skin model. These results clearly indicate that restoration of the energy pool in mitochondria increased cellular self‐defense mechanism. These data show the important role played by the mitochondrial energy metabolism on the aging process, and indicate a possible therapy that can be used to counteract this negative effect. Treatment with creatine seems to provide the necessary boost to the cellular metabolism, which leads to an induction of a significant amount of protection and repair to human skin cells.
Influence of cleansing on stratum corneum tryptic enzyme in human skin
Authors: Schepky A. G. , Holtzmann U. , Siegner R. , Zirpins S. , Schmucker R. , Wenck H. , Wittern K. P. , Biel S. S. 
Published: September 2004

SynopsisDesquamation in human skin is a well‐balanced process of de novo production of corneocytes and their shedding from the skin surface. The proteolysis of corneodesmosomes is an important step in the final desquamation process. In the degradation of these adhesion molecules, the stratum corneum tryptic enzyme (SCTE) plays a key role. In initial studies with extracts of porcine epidermis, SCTE was shown to be inactivated by low concentrations of sodium lauryl ether sulphate (SLES). These in vitro findings were supported by in situ results obtained by measuring the release of fluorescent dyes coupled to trypsin‐specific substrates incubated on human skin cross‐sections. Moreover, in further studies, it could be demonstrated that the SCTE activity in the human horny layer decreases after in vivo application of cleansing products containing SLES. After repeated washing of human volunteers with tap water, a standard market cleansing product (SLES/betaine system) or a new improved cleansing product (SLES/betaine/disodium cocoyl glutamate system), the specific SCTE activity was determined in extracts from the uppermost layers of the stratum corneum. It could be shown that after application of the new formula the remaining SCTE activity was significantly higher than after use of the standard market formula. This ex vivo approach has proven to be very helpful for measuring surfactant effects on human skin enzymes. Using this assay, we developed an improved shower gel formula, which leads to a significantly higher skin enzyme activity after application, compared to a standard market formula.
Use of the synthetic superoxide dismutase/catalase mimetic EUK‐134 to compensate for seasonal antioxidant deficiency by reducing pre‐existing lipid peroxides at the human skin surface
Authors: Declercq L. , Sente I. , Hellemans L. , Corstjens H. , Maes D. 
Published: September 2004

SynopsisThe generation of reactive oxygen species (ROS) in UV‐exposed skin is believed to contribute to the photoaging process. The stratum corneum (SC) contains a variety of enzymatic and non‐enzymatic antioxidants to protect against various environmental sources of free radicals. We have previously shown a seasonal variation in SC catalase activity with strong deactivation in sun‐exposed skin in the summer, whereas SC superoxide dismutase (SOD) activity remained intact in those conditions. This potentially leads to the local overproduction of H2O2. The oxidized lipid squalene hydroperoxide accumulates at the surface of sun‐exposed skin in the summer and upon exposure to ultravoilet A (UVA) doses as low as 0.1 J cm−2 and adequate protection against excessive lipid peroxidation at times of UV exposure should be aimed for. We have been using the induction of lipid hydroperoxides at the skin surface by a single dose of UVA (1 J cm−2) as a model system to evaluate the protective effect of antioxidants in vivo. Topical treatment with the synthetic SOD/catalase mimetic molecule (EUK‐134) 1 h before UVA exposure reduced the level of lipid peroxides at the surface of UVA‐exposed skin but also baseline peroxide levels on non‐irradiated skin were reduced in a dose‐dependent fashion. In contrast to alpha‐tocopherol, EUK‐134 even reduced the level of lipid peroxides at the surface of UVA‐exposed skin when it was applied after irradiation. We confirmed that this salen–manganese complex was able to reduce squalene hydroperoxide levels in vitro, suggesting peroxidase‐like activity towards organic peroxides. These data support the concept that the synthetic SOD/catalase mimetic EUK‐134 might be able to compensate for seasonal deficiencies in antioxidant defense capacity at the skin surface, thereby contributing to an optimal protection of the skin against the accumulation of oxidative damage.
An Australian “Historikerstreit”? Review Article
Authors: Bonnell Andrew G. , Crotty Martin 
Published: September 2004

Frontier Conflict. The Australian Experience. Edited by Bain Attwood and S.G. Foster Historical Records of Australia Series III Despatches and Papers Relating to the History of Tasmania, Vol. VIII, Tasmania, January‐December 1829. Edited by Peter Chapman The History Wars. By Stuart Macintyre and Anna Clark Whitewash. On Keith Windschuttle's Fabrication of Aboriginal History. Edited by Robert Manne The Fabrication of Aboriginal History. By Keith Windschuttle
Perceptual organization of motions in pigeons (Columba livia)1
Authors: USHITANI TOMOKAZU , FUJITA KAZUO , SATO AKIRA 
Published: September 2004

Abstract:  We investigated whether pigeons perceived relative motion of more than one object. We trained pigeons to match a white target dot moving vertically at a constant speed to one color and the same dot moving diagonally to another. In Experiment 1, we presented an additional yellow dot (accompanying dot) moving horizontally near the target. We hypothesized that the pigeons would match the diagonal motion to the color for “vertical motion” and vice versa if they perceived relative motion of the target and the accompanying dot. We reduced the size and the speed of the stimuli by half in Experiment 2 and changed the movement pattern of the target to a sine‐function in Experiment 3. In Experiment 4, we presented two accompanying dots. However, the results of Experiments 1 to 4 showed no evidence that pigeons perceived relative motion. In Experiment 5, we substituted a moving frame for accompanying dots. The pigeons tended to respond to the color corresponding to the relative motion. These results suggest that pigeons may organize a set of moving objects as one object moving relative to the other in some stimulus displays in which the second object constitutes an explicit reference frame.
Use of experimenter‐given directional cues by a young white‐handed gibbon (Hylobates lar)1
Authors: INOUE YOICHI , INOUE ETSUKO , ITAKURA SHOJI 
Published: September 2004

Abstract:  A three‐year‐old white‐handed gibbon (Hylobates lar) was tested in terms of her ability to follow experimenter‐given directional cues in an object‐choice task. Four conditions were run: the experimenter baited one of two cups and then gave one of the following four directional cues: (a) pointing at the baited cup from a short distance (5 cm); (b) pointing at the target from a long distance (20 cm); (c) orienting body, head, and eyes toward the baited cup; and (d) orienting eyes only toward the baited cup. A young gibbon was able to use all of the experimenter‐given cues to obtain hidden food rewards. Several possible reasons for the gibbon's superior performance in comparison to other primates reported in the existing literature were discussed.