bluuebunny/crossref_metadata_2025_split huggingface dataset:
Androgen 5‐Alpha‐Reductase Type 2 is Highly Expressed and Active in Rat Spinal Cord Motor Neurones
Authors: Pozzi P. , Bendotti C. , Simeoni S. , Piccioni F. , Guerini V. , Marron T. U. , Martini L. , Poletti A. 
Published: August 2003

AbstractSpinal cord motoneurones express high levels of androgen receptor. However, in responsive tissue, the effects of testosterone is often mediated by the more potent androgenic derivative 5‐alpha‐dihydrotestosterone (DHT). This compound is formed in androgen target cells by the enzyme 5‐alpha‐reductase. Two isoforms of the 5‐alpha‐reductase, with limited degree of homology, have been cloned, type 1 and type 2. The low affinity‐constitutive type 1 isoenzyme is widely distributed in the body; the high affinity‐androgen regulated 5‐alpha‐reductase type 2 is confined to androgen‐dependent structures and shows a peculiar pH optimum at acidic values. We have previously shown that high levels of 5‐alpha‐reductase activity are detectable in rat spinal cord. Here, using reverse transcriptase‐polymerase chain reaction, we show that both isoforms are expressed in the whole spinal cord of the rat. The enzymatic pH optimum measured in immortalized spinal cord motoneurones (NSC34) is typical of the type 2 isoenzyme. Using in situ hybridization technique, we found that 5‐alpha‐reductase type 2 is confined to the motoneuronal cells of the anterior horns of the rat spinal cord, the cells that also are known to express high levels of androgen receptor. Because of the close association of androgen receptor and 5‐alpha alpha‐reductase type 2, motoneuronal cells should be considered as target cells for androgens.
Impaired Somatodendritic Responses to Pituitary Adenylate Cyclase‐Activating Polypeptide (PACAP) of Supraoptic Neurones in PACAP type I ‐Receptor Deficient Mice
Authors: Jamen F. , Alonso G. , Shibuya I. , Widmer H. , Vacher C.‐M. , Calas A. , Bockaert J. , Brabet P. , Dayanithi G. 
Published: August 2003

AbstractThe role of pituitary adenylate cyclase‐activating polypeptide (PACAP) type I receptor (PAC1 receptor) in regulating hypothalamic supraoptic neurones was investigated using PAC1 receptor‐deficient male mice (PAC1−/−). The effects of PACAP on [Ca2+]i were investigated in freshly dissociated supraoptic neurones and on the somatodendritic release of vasopressin and oxytocin, examined on intact supraoptic nuclei. In supraoptic neurones from wild‐type mice (PAC1+/+), 100 nm PACAP induced an increase in [Ca2+]i and release of vasopressin and oxytocin, whereas in heterozygous (PAC1+/−) and null‐mutant mice (PAC1−/−), PACAP was much less effective. PACAP had no effect on these two parameters when applied to isolated neurohypophysial nerve terminals of PAC1+/+ and PAC1−/− mice, and rats. In conclusion, the PAC1 receptor is solely responsible for the PACAP‐induced [Ca2+]i signalling and secretion of vasopressin and oxytocin in the somatodendritic region of supraoptic neurones.
Leptin‐Target Neurones of the Rat Hypothalamus Express Somatostatin Receptors
Authors: Stepanyan Z. , Kocharyan A. , Pyrski M. , Hübschle T. , Watson A. M. D. , Schulz S. , Meyerhof W. 
Published: August 2003

AbstractHypothalamic leptinoceptive neurones can be visualized by histochemical demonstration of leptin‐induced nuclear translocation of the signalling molecule STAT3. We investigated the relationship of the leptinoceptive neurones to the somatostatin signalling system. With double‐labelling immunohistochemistry, we studied the colocalization of leptin‐activated transcription factor, STAT3, with somatostatin receptor subtypes, sst1, sst2A, sst2B, sst3 and sst4, or the neuropeptide itself, in the rat hypothalamus. Immunoreactivity for all the entities was widely distributed throughout the entire hypothalamus. Despite the wide distribution, only few cases of colocalization of somatostatin with leptin‐activated STAT3 were detected in the paraventricular, arcuate and dorsomedial nuclei. A moderate to high degree of colocalization of nuclear STAT3 and all investigated subtypes of somatostatin receptors was found in the lateral and dorsal hypothalamic areas and in the dorsomedial hypothalamic nucleus. Immunoreactivity for sst1, sst2B and sst4 was present in STAT3‐containing nuclei of the paraventricular, periventricular, arcuate and ventromedial hypothalamic neurones, as well as in the retrochiasmatic and posterior hypothalamic areas. Despite the wide distribution of sst2A in the rat hypothalamus, few events of colocalization with leptin‐activated STAT3 were observed in the dorsomedial nucleus and in the lateral and dorsal hypothalamic areas only. Many leptin‐responsive neurones of the dorsal, lateral, periarcuate, perifornical and posterior hypothalamic areas, as well as in the ventromedial and dorsomedial hypothalamic nuclei, displayed sst3 immunoreactivity at their neuronal cilia. These results provide strong anatomical evidence for the direct interaction of leptin and the somatostatin systems in neuroendocrine control loops such as the energy homeostasis, growth or stress response.
Responses of Cells in the Rat Suprachiasmatic Nucleus In Vivo to Stimulation of Afferent Pathways are Different at Different Times of the Light/Dark Cycle
Authors: Saeb‐Parsy K. , Dyball R. E. J. 
Published: August 2003

AbstractConventional extracellular recordings were made from single cells in the suprachiasmatic nucleus (SCN) region of the anaesthetized rat. Each cell was tested for its response to stimulation at three sites; the contralateral optic nerve, the ipsilateral supraoptic nucleus (SON) or the ipsilateral arcuate nucleus (ARC) to determine whether the behaviour of the synapses in the SCN was different at different times. Responses to stimulation were tested once each hour and assessed by creating peristimulus time histograms. Excitatory, inhibitory or complex (consisting of more than one component) responses were seen. The responses of some cells that were recorded for several hours changed with time. Changes were seen in the responses of SCN cells to stimulation of the ARC (31/91 cells) and the SON (26/90 cells) regions, but only rarely to stimulation of the optic nerve (2/72 cells). Such differences in proportion are unlikely to have occurred by chance (P < 0.001; chi‐square test). Changes seen included the appearance of both excitatory and inhibitory responses in cells that were initially unresponsive. In some cells, one component of a complex response remained constant while another component changed with time. When the cells in the SCN were treated as a group, the proportion of excitatory, inhibitory or complex responses to ARC stimulation did not remain constant throughout the light/dark cycle (P = 0.014; chi‐square test). The proportion of excitatory, inhibitory or complex responses to SON and optic nerve stimulation showed no significant variation with the light/dark cycle. If a change in response can be interpreted as a change in the behaviour of a neural connection, the results imply that some of the projections to the SCN from within the hypothalamus change at different times of the light/dark cycle, whereas no change could be seen in the input from the optic nerve. Thus, some of the connections of the SCN appear not to be hard wired, but change rapidly with time.
Evaluation of the clinical and allergen specific serum immunoglobulin E responses to oral challenge with cornstarch, corn, soy and a soy hydrolysate diet in dogs with spontaneous food allergy
Authors: Jackson H. A. , Jackson M. W. , Coblentz L. , Hammerberg B. 
Published: August 2003

Abstract Fourteen dogs with known clinical hypersensitivity to soy and corn were maintained on a limited antigen duck and rice diet until cutaneous manifestations of pruritus were minimal (78 days). Sequential oral challenges with cornstarch, corn and soy were then performed. Subsequently, the dogs were fed a diet containing hydrolysed soy protein and cornstarch. Throughout the study period the dogs were examined for cutaneous manifestations of pruritus and, additionally, serum was collected for measurement of allergen‐specific and total immunoglobulin (Ig)E concentrations. Intradermal testing with food antigens was performed prior to entry into the study and after 83 days. A statistically significant clinical improvement was measured between days 0 and 83. Significant pruritus was induced after oral challenge with cornstarch, corn and soy (P = 0.04, 0.002, 0.01, respectively) but not with the hydrolysed diet (P = 0.5). The positive predictive value of the skin test for soy and corn allergy was reduced after feeding a soy and corn free diet. Although increases in soy and corn‐specific serum IgE concentrations were measured in individual dogs post challenge they were not statistically significant and could not be used to predict clinical hypersensitivity.
Efficacy of milbemycin oxime in the treatment of canine generalized demodicosis: a retrospective study of 99 dogs (1995–2000)
Authors: Holm Birgit R. 
Published: August 2003

Abstract Ninety‐nine dogs diagnosed with generalized demodicosis were treated with milbemycin oxime. Cases diagnosed before two years of age were classified as juvenile‐onset (53%) and those diagnosed after two years of age as adult‐onset (47%). Dogs were considered cleared of mites when none could be demonstrated in scrapings and cured if no relapse was seen for 12 months. Eighty‐five per cent (84/99) were cured with milbemycin oxime used for 1–6 months (mean 2.3 months) at a dosage of 0.5–1.6 mg kg−1body weight (mean 0.75 mg kg−1). No significant difference in dosage or treatment time was seen between juvenile and adult cases. Chance of cure was significantly better in young animals (cured cases mean age 2.97 years) than in older animals (not cured cases mean age 8.02 years). Start of treatment early in the course of disease gave a significantly better chance of cure. Cases with severe pododemodicosis had less chance of a cure (9/11 not cured).
Hereditary nasal parakeratosis in Labrador retrievers: 11 new cases and a retrospective study on the presence of accumulations of serum (‘serum lakes’) in the epidermis of parakeratotic dermatoses and inflamed nasal plana of dogs
Authors: Peters Jeanine , Scott Danny W. , Erb Hollis N. , Miller William H. 
Published: August 2003

Abstract  We report 11 new cases of hereditary nasal parakeratosis in Labrador retrievers. The disease was first observed when the dogs were 6 months to 2 years of age, and affected dogs of either sex and all coat colours. Hyperkeratosis and depigmentation were confined to the nasal planum, and affected dogs were otherwise healthy. The principal histological findings in biopsy specimens were marked diffuse parakeratotic hyperkeratosis, multiple intracorneal serum lakes and superficial interstitial‐to‐interface lymphoplasmacytic dermatitis. Topical applications of propylene glycol in water or white petrolatum were often effective for treatment of the dermatosis. However, continued applications were required to maintain a beneficial response. A retrospective histological study of parakeratotic inflammatory diseases of canine haired skin and inflammatory diseases of the canine nasal planum was performed. The degree of parakeratotic hyperkeratosis and the number and size of intracorneal serum lakes were evaluated. The degree of parakeratotic hyperkeratosis was greater in hereditary nasal parakeratosis specimens than that seen in discoid lupus erythematosus and Malassezia dermatitis. There were more serum lakes in hereditary nasal parakeratosis specimens than in specimens from dogs with discoid lupus erythematosus, Malassezia dermatitis, primary seborrheic dermatitis or zinc‐responsive dermatosis. Significant differences in sizes of serum lakes (if present) were not seen.
Biochemical characterization of the vanilloid receptor 1 expressed in a dorsal root ganglia derived cell line
Authors: Jahnel Ricarda , Dreger Mathias , Gillen Clemens , Bender Olaf , Kurreck Jens , Hucho Ferdinand 
Published: August 2003

The vanilloid receptor VR1 is an ion channel predominantly expressed by primary sensory neurons involved in nociception. Here we describe its biochemical properties and assess the subcellular localization, the glycosylation state and the quaternary structure of VR1 expressed in HEK293 cells and in the DRG‐derived cell line F‐11 (N18TG2 mouse neuroblastoma × rat dorsal root ganglia, hybridoma). VR1 was found to be glycosylated in both cell types. Of the five potential N‐glycosylation sites, the predicted transient receptor potential channel‐like transmembrane folding proposes N604 is localized extracellularly. We used site‐directed mutagenesis to mutate the Asn at position 604 to Thr. This mutated VR1 was not glycosylated, confirming the extracellular location of N604 and its role as the exclusive site of glycosylation of the VR1 protein. VR1 occured in high molecular mass complexes as assessed by blue native PAGE. In the presence of limited amounts of SDS dimers, trimers and tetramers of VR1 were observed, consistent with the predicted tetrameric quaternary structure of the receptor. Cross‐linking with dimethyladipimidate yielded almost exclusively dimers.Whereas VR1 localized both to the plasma membrane and to intracellular membranes in HEK293 cells, it localized predominantly to the plasma membrane in F‐11 cells. Using confocal laserscanning microscopy, we observed an enrichment of anti‐VR1 immunoreactivity in neurite‐like structures of F‐11 cells. In the light of conflicting literature data on biochemical characteristics of VR1, our data suggest that dorsal root ganglion‐derived F‐11 cells provide a powerful experimental system for the study of VR1 biochemistry.
Glucose sensing in the intestinal epithelium
Authors: Dyer Jane , Vayro Steven , King Timothy P. , Shirazi‐Beechey Soraya P. 
Published: August 2003

Dietary sugars regulate expression of the intestinal Na+/glucose cotransporter, SGLT1, in many species. Using sheep intestine as a model, we showed that lumenal monosaccharides, both metabolisable and nonmetabolisable, regulate SGLT1 expression. This regulation occurs not only at the level of transcription, but also at the post‐transcriptional level. Introduction of d‐glucose and some d‐glucose analogues into ruminant sheep intestine resulted in > 50‐fold enhancement of SGLT1 expression. We aimed to determine if transport of sugar into the enterocytes is required for SGLT1 induction, and delineate the signal‐transduction pathways involved.A membrane impermeable d‐glucose analogue, di(glucos‐6‐yl)poly(ethylene glycol) 600, was synthesized and infused into the intestines of ruminant sheep. SGLT1 expression was determined using transport studies, Northern and Western blotting, and immunohistochemistry. An intestinal cell line, STC‐1, was used to investigate the signalling pathways.Intestinal infusion with di(glucos‐6‐yl)poly(ethylene glycol) 600 led to induction of functional SGLT1, but the compound did not inhibit Na+/glucose transport into intestinal brush‐border membrane vesicles. Studies using cells showed that increased medium glucose up‐regulated SGLT1 abundance and SGLT1 promoter activity, and increased intracellular cAMP levels. Glucose‐induced activation of the SGLT1 promoter was mimicked by the protein kinase A (PKA) agonist, 8Br‐cAMP, and was inhibited by H‐89, a PKA inhibitor. Pertussis toxin, a G‐protein (Gi)‐specific inhibitor, enhanced SGLT1 protein abundance to levels observed in response to glucose or 8Br‐cAMP.We conclude that lumenal glucose is sensed by a glucose sensor, distinct from SGLT1, residing on the external face of the lumenal membrane. The glucose sensor initiates a signalling pathway, involving a G‐protein‐coupled receptor linked to a cAMP–PKA pathway resulting in enhancement of SGLT1 expression.
Structural characterization of the lipopolysaccharide O‐polysaccharide antigen produced by Flavobacterium columnare ATCC 43622
Authors: MacLean Leann L. , Perry Malcolm B. , Crump Elizabeth M. , Kay William W. 
Published: August 2003

The structure of the antigenic O‐chain polysaccharide of Flavobacterium columnare ATCC 43622, a Gram‐negative bacterium that causes columnaris disease in warm water fish, was determined by high‐field 1D and 2D NMR techniques, MS, and chemical analyses. The O‐chain was shown to be an unbranched linear polymer of a trisaccharide repeating unit composed of 2‐acetamido‐2‐deoxy‐d‐glucuronic acid (d‐GlcNAcA), 2‐acetamidino‐2,6‐dideoxy‐l‐galactose (l‐FucNAm) and 2‐acetamido‐2,6‐dideoxy‐d‐xylo‐hexos‐4‐ulose (d‐Sug) (1 : 1 : 1), having the structure:
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Surface diffraction studies of 2D crystals of short fatty alcohols at the air-water interface
Authors: Renault A. , Legrand J. F. , Goldmann M. , Berge B. 
Published: August 2003

Using X ray surface diffraction we have investigated crystalline monolayers of short alcohols (1-decanol to 1-tetradecanol) at the air-water interface in the vicinity of the first order transition corresponding to 2D melting (Tm(2D)). The diffraction patterns in the solid phase are in agreement with a 2D hexagonal close-packing. The lattice parameter value is 5.00 Å just below Tm(2D) and amounts 4.90 Å at Tm(2D)-20 K. The resolution limited Bragg peaks indicate a large crystalline coherence length. At the approach of the 2D melting point, the observed increase of the Debye Waller factor is attributed to critical fluctuations.
Molecular theory of order electricity
Authors: Osipov M. A. , Sluckin T. J. 
Published: August 2003

The concept of order electricity has been employed by Durand, Barbero and colleagues to explain, in particular, the existence of equilibrium conical anchoring at liquid crystal interfaces. In this paper we examine this concept from a molecular point of view, using the density functional theory of liquid crystals. We show that the long range nature of the electrostatic force between molecules with permanent quadrupoles creates formal problems with rather profound consequences on the link between microscopic and macroscopic formulations of liquid crystal theory. One result is that the Landau-de Gennes gradient expansion must be employed with extreme caution in an inhomogeneous nematic. These formal problems have analogues in the theory of dielectrics and were explored by Ewald long ago. In addition we derive from a statistical mechanical viewpoint the phenomenological relations used to describe order electricity, and explore in detail the consequences of order electricity at an isotropic-nematic interface and at a nematic-substrate interface.
Spirals of Silence: The Dynamic Effects of Diversity on Organizational Voice*
Authors: Bowen Frances , Blackmon Kate 
Published: August 2003

ABSTRACT When will individuals speak up about organizational issues, and when will they remain silent? We suggest that organizational voice will be significantly influenced by individuals’ perceptions of the attitudes towards an issue within their workgroup. In particular, individuals will be more likely to speak up when they believe that their position is supported by others, and remain silent when they believe that it is not. We explain this using the ‘spiral of silence’ proposed by Noelle‐Neumann (1974, 1985, 1991) and widely used in public opinion research, which explains how majority opinions become dominant over time and minority opinions weakened.Spirals of silence within groups can restrict the open and honest discussion that is essential to organizational improvement. Noelle‐Neumann's spiral of silence emphasizes the horizontal pressures that the threat of isolation and corresponding fear of isolation exert to keep people from being open and honest about their opinions. We argue in this paper that the fear and threat of isolation are particularly powerful for members of invisible minorities such as gay and lesbian employees. We propose a second, vertical ‘spiral of silence’ may develop through processes at a more micro level within the workgroup and organization. This second spiral begins with the inability to fully express one's personal identity within the workgroup because of a negative climate of opinion towards a particular aspect of one's identity. This may be especially true for ‘invisible’ sources of diversity such as sexual orientation. Revealing a potentially disruptive identity might impair social cohesion: concealing it, however, can inhibit social exchange and task exchange and reduce self‐efficacy, leading to organizational silence. However, an alternate virtuous spiral can result in which individuals will feel empowered to express organizational voice.
Marital Conflict and Children's Adjustment: Parental Hostility and Children's Interpretations as Mediators
Authors: Stocker Clare M. , Richmond Melissa K. , Low Sabina M. , Alexander Elise K. , Elias Nadine M. 
Published: August 2003

AbstractThe associations between marital conflict, maternal and paternal hostility, children's interpretations of marital conflict, and children's adjustment were examined in a sample of 136 school‐aged children and their parents. Observational measures were collected from videotapes of marital interaction and family interaction. Self‐report data were collected from parents and children. Results showed that mothers’ and fathers’ hostility mediated the association between martial conflict and children's internalizing and externalizing behavior problems. Children's feelings of being to blame for marital conflict and being threatened by it mediated between marital conflict and children's internalizing problems but not their externalizing problems.
Are Children More Angered and Distressed by Man–Child than Woman–Child Arguments and by Interadult versus Adult–Child Disputes?
Authors: Harger JoAnn , El‐Sheikh Mona 
Published: August 2003

AbstractSix to 10‐year‐olds’ responses to witnessing videotapes of five contexts of verbal and physical arguments (man–woman, man–boy, man–girl, woman–boy, and woman–girl) were compared to examine the hypotheses that: (1) man–child disputes would be perceived more negatively and evoke more negative affect in children than woman–child conflict; and (2) man–woman conflict would be viewed more negatively and elicit greater negative emotions in children than adult–child arguments. Results lend support to the two predictions, and consistent with the emotional security hypothesis, reveal that (1) man–child conflict evoked more sadness and fear in children than woman–child disputes; (2) man–woman arguments evoked more intense feelings of sadness and fear than any of the adult–child disputes, and the adult in the conflicts was perceived as more sad and scared when arguing with the spouse than with the girl or boy; and (3) physical conflict evoked more negative affect than verbal disputes.
Preschoolers’ Beliefs About the Stability of Antisocial Behavior: Implications for Navigating Social Challenges
Authors: Giles Jessica W. , Heyman Gail D. 
Published: August 2003

AbstractThe relation between 3‐ to 5‐year‐old children's beliefs about sociomoral stability (the tendency for antisocial behavior to remain stable over time) and their reasoning about peer interactions was examined. Participants were 100 preschoolers enrolled in a Head Start program. Children who endorsed sociomoral stability beliefs were less likely than their peers to make prosocial inferences, were rated by their teachers as less likely to engage in prosocial behavior, and were more likely to endorse the use of aggression to solve conflict with peers. These findings suggest that as early as preschool, children have general patterns of beliefs about the stability of antisocial behavior that predict a tendency to de‐emphasize prosocial strategies that can mediate social challenges.