bluuebunny/crossref_metadata_2025 huggingface dataset:
GENESiS: creating a composite index of the vulnerability to anxiety and depression in a community-based sample of siblings
Authors: Sham PC , Sterne A , Purcell S , Cherny S , Webster M , Rijsdijk F , Asherson P , Ball D , Craig I , Eley T , Goldberg D , Gray J , Mann A , Owen M , Plomin R
Published: May 2007

There is considerable evidence for a unitary and dimensional view of the genetic vulnerability to symptoms of anxiety and depression. The GENESiS (Genetic Environmental–Nature of Emotional States in Siblings) Study aims to use a multivariate approach to detect genetic loci that contribute to individual differences in this vulnerability dimension. The study used the UK General Practice Research Framework to generate a community-based sample of siblings. Questionnaire measures of anxiety/depression included the short form of the neuroticism scale from the revised Eysenck Personality Questionnaire (EPQ-N), the General Health Questionnaire (GHQ-12), and the anxious arousal and high positive affect subscales from the Mood and Anxiety Symptoms Questionnaire (MASQ-AA and MASQ-HPA). Genetic model-fitting of 2658 unselected sibships provided evidence for a single common genetic (familial) factor that accounted for a substantial proportion of the genetic variances and covariances of these four measures. Using the parameter estimates of this model, we constructed a composite index of this common genetic factor. This index, which has a sib correlation of 0.22, will be used as a quantitative phenotype in the molecular genetic phase of GENESiS. Twin Research (2000) 3, 316–322.
The Influence of Zygosity and Chorion Type on Fat Distribution in Young Adult Twins Consequences for Twin Studies
Authors: Loos Ruth J.F. , Beunen Gaston , Fagard Robert , Derom Catherine , Vlietinck Robert
Published: May 2007

An adverse intra-uterine environment has been associated with abdominal fat distribution in singletons. Twins often have a low birth weight and a short gestation. Therefore, they may have an increased risk to develop abdominal obesity. Furthermore, monozygotic monochorionic twins (MZ MC) have a larger intra-pair birth weight difference compared to monozygotic dichorionic twins (MZ DC). If adult anthropometry is programmed in utero, this may affect the intra-pair correlations in adulthood and, consequently, also the results from the classic twin method to estimate genetic and environmental influences. In the present study, we compared the absolute values, the intra-pair differences, and the intra-pair correlations of body mass, height, BMI, and abdominal fat distribution of 424 MZ MC, MZ DC and dizygotic (DZ) twin pairs (aged 18–34 yrs). DZ, MZ DC and MZ MC twins did not differ for most anthropometric characteristics. Only MZ women tended (p = 0.03) to accumulate more abdominal fat compared to DZ twins. Overall, the contribution of zygosity and chorion type to adult anthropometry was rather low (≤ 1.7%). Although the intra-pair birth weight difference of MZ MC pairs (10.5% in men, 12.3% in women) was significantly larger compared to that of MZ DC pairs (6.9% and 9.2% resp.), the intra-pair differences in adult anthropometry were similar for both MZ twin types. Also the intra-pair correlations of MZ MC and MZ DC pairs were strikingly alike, suggesting no significant influence of the prenatal environment on adult concordance. In conclusion, the substantial difference in the prenatal environment of MZ MC and MZ DC twins did not result in a difference in intra-pair concordance of adult anthropometry and fat distribution. Therefore, we suggest that the chorion type of MZ twins does not bias the twin design and the estimation of the genetic contribution to adult anthropometry.
Association of Birth Weight and Current Body Size to Blood Pressure in Female Twins
Authors: Nowson Caryl A. , MacInnis Robert J. , Hopper John L. , Alexander Jo L. , Paton Lynda M. , Margerison Claire , Wark John D.
Published: May 2007

It has been proposed that low birth weight is associated with high levels of blood pressure in later life. The aim of this study was to assess the relationship of blood pressure to birth weight and current body size during growth and adulthood. A total of 711 female multiple births, with one group of 244 in their growth phase mean age 12.0 (2.3)(SD) years and the other of 467 adults (mean age 35.2 (12.6) years), had height, weight and both systolic (SBP) and diastolic (DBP) blood pressures measured, and self-reported their birth weight. Regression analyses were performed to assess the cross-sectional and within-pair associations of blood pressure to birth weight, with and without adjustments for current body size. Within-pair analysis was based on 296 twin pairs. Cross-sectionally, a reduction in birth weight of 1 kg was associated with 2 to 3 mm Hg higher age-adjusted SBP, which was of marginal significance and explained about 2% of the population variance. Adjustment for body mass index did not significantly change this association. Within-pair analyses found no association between birth weight and SBP or DBP, even after adjusting for current body size. After age, current body size was the strongest predictor of systolic BP. The weak association of blood pressure to birth weight cross-sectionally is of interest, but any within-pair effect of birth weight on blood pressure must be minimal compared with the effect of current body size.
Intergenerational Effect of an Adverse Intrauterine Environment on Perturbation of Glucose Metabolism
Authors: Reusens Brigitte , Remacle Claude
Published: May 2007

Human epidemiological and animal studies have revealed the late consequences of malnutrition during gestation and early life on the health of the offspring. These studies have highlighted the inverse relationship between birth weight and the incidence of insulin resistance and type 2 diabetes later in life. The aim of this paper is to review the different means of achieving foetal malnutrition and its consequences even for a next generation, in animal models and to identify key area for further research. We address the impact of two models of maternal malnutrition (protein restriction and caloric restriction) as well as the impact of maternal diabetes, the three maternal conditions leading to perturbed foetal nutritional environment. Particular emphasis is given to the endocrine pancreas and the insulin sensitive tissues. More specifically, alterations of the foetal nutritional environment perturb the development of the endocrine pancreas and target the ß cell mass at birth. Some adaptations later in life may take place but stress situations such as pregnancy and ageing precipitate the animals to glucose intolerance and insulin resistance. Even the next generation features alterations in the development of the endocrine pancreas. Some mechanisms by which the foetal ß cell mass is altered are approached in this review and specific attention is paid to the amino acid profile. The preventive role of taurine is discussed.
Genetic and Environmental Influences on Self-Esteem in a Japanese Twin Sample
Authors: Kamakura Toshimitsu , Ando Juko , Ono Yutaka
Published: May 2007

The purpose of the present study is to clarify the mechanism of Japanese self-esteem (SE) in genetic and environmental influences using twin methodology. Eighty-one pairs of adolescent twins, including 50 pairs of monozygotic (MZ) twins and 31 pairs of dizygotic (DZ) twins, participated in this study. Self-esteem was assessed using the Rosenberg Self-Esteem Scale (RSES), translated into Japanese. As a result of using univariate twin analyses, model comparisons using the Akaike Information Criterion (AIC) indicated that the AE model was the best fit (AIC = −5.35). In the best-fitting AE model, the heritability (a2) of SE was revealed to be moderate, accounting for 49% of the variance; environmental influences (individual-specific environmental factors) explained 51% of the variance. These results are consistent with the findings of some behavioral genetics studies of SE in the West and show that there is no difference between Western and Japanese populations in the mechanism of SE considering genetic and environmental influences. The results also suggest the importance of considering both genetic and environmental factors in studies of Japanese SE.
Examining the Dimensions of Intimacy in Twin and Peer Relationships
Authors: Foy Andrea K. , Vernon Phillip A. , Jang Kerry
Published: May 2007

While it is widely assumed that twinship involves high levels of intimacy to the detriment of other relationships, an examination of twinship using measures of intimacy has not yet been conducted. Participants were 214 individual twins (128 MZ, 62 DZ same-sex, and 24 DZ mixed-sex) between 16–73 years of age. Twins completed measures of intimacy in reference to their co-twin, their closest same-sex friend, and their closest other-sex friend. As expected, the highest level of intimacy was reported for the co-twin. Contrary to expectation, MZ twins did not report significantly higher levels of intimacy with their co-twin, or significantly lower levels of intimacy with their closest friends when compared to DZ same-sex or DZ mixed-sex twins. Furthermore, twins who reported high levels of intimacy with their co-twin did not report significantly lower levels of intimacy with their closest friends. Implications and directions for future research are discussed.
Genetic and Environmental Influences on the Associations Between Attention Problems and Other Problem Behaviors
Authors: Schmitz Stephanie , Mrazek David A.
Published: May 2007

Problem behavior in children shows a high degree of cooccurrence, both within the domains of internalizing and externalizing behaviors and across domains. Maternal ratings of 207 same- and opposite-sex twin pairs on the Child Behavior Checklist (CBCL/4–18; Achenbach, 1991) were used to determine the etiology of these associations. In the current sample of 4- to 11-year-old children (mean age: 7.6 years) phenotypic correlations were .68 between Internalizing and Externalizing, between .41 and .66 within the internalizing scales, and between .58 and .71 within the externalizing scales. Correlations across domains on the scale level were of similar magnitude. Genetic and shared environmental correlations were generally high, with the exception of the somatic complaints scale which showed low genetic correlations with other scales. These findings of uniformly high shared etiology was seen within and across domains. For example, Attention Problems showed genetic correlations of .65 with Delinquent Behavior and .76 with Aggressive Behavior; the genetic correlations of Attention Problems with internalizing scales were .71 for Anxious/Depressed and .79 for Withdrawn; a low genetic correlation was only shown for the Somatic Complaints scale (rg = .16). Although the magnitude of shared environmental contributions was lower, the environmental correlations were close to unity, indicating that the same family environmental factors were involved in aspects of problem behavior when assessed across domains. Results for the Attention Problems scale were similar to other disruptive behavior, justifying its inclusion with the externalizing scales.
Multifunctional Laryngeal Premotor Neurons: Their Activities during Breathing, Coughing, Sneezing, and Swallowing
Authors: Shiba Keisuke , Nakazawa Ken , Ono Kenichi , Umezaki Toshiro
Published: May 2007

To examine whether motor commands of two or more distinct laryngeal motor patterns converge onto a common premotor network, we conducted dual recordings from the laryngeal adductor motoneuron and its premotor neuron within the brainstem respiratory circuitry during fictive breathing, coughing, sneezing, and swallowing in decerebrate paralyzed cats. Expiratory neurons with an augmenting firing pattern (EAUG), whose action potentials evoked monosynaptic IPSPs in the adductor motoneurons, sharply fired during the expulsive phases of fictive coughing and sneezing, during which the adductor motoneurons transiently repolarized. In contrast, these premotor neurons were silent during the swallow-related hyperpolarization in adductor motoneurons. These results show that one class of medullary respiratory neuron, EAUG, is multifunctional and shared among the central pattern generators (CPGs) for breathing, coughing, and sneezing. In addition, although the CPGs underlying these three behaviors and the swallowing CPG do overlap, EAUG neurons are not part of the swallowing CPG and, in contrast to the other three behaviors, are not a source of inhibitory input to adductor motoneurons during swallowing.
Mechanisms for Synapse Specificity during Striatal Long-Term Depression
Authors: Singla Sheela , Kreitzer Anatol C. , Malenka Robert C.
Published: May 2007

Endocannabinoid (eCB)-mediated forms of long-term synaptic plasticity occur in several brain regions, but much remains unknown about their basic properties and underlying mechanisms. Here, we present evidence that eCB-mediated long-term depression (eCB-LTD) at excitatory synapses on medium spiny neurons in the striatum requires presynaptic activity coincident with CB1 receptor activation. This dual requirement for CB1 activation and presynaptic activity is a mechanism by which eCB-LTD may be made synapse specific.
Selective Cochlear Degeneration in Mice Lacking the F-Box Protein, Fbx2, a Glycoprotein-Specific Ubiquitin Ligase Subunit
Authors: Nelson Rick F. , Glenn Kevin A. , Zhang Yuzhou , Wen Hsiang , Knutson Tina , Gouvion Cynthia M. , Robinson Barbara K. , Zhou Zouping , Yang Baoli , Smith Richard J. H. , Paulson Henry L.
Published: May 2007

Little is known about the role of protein quality control in the inner ear. We now report selective cochlear degeneration in mice deficient in Fbx2, a ubiquitin ligase F-box protein with specificity for high-mannose glycoproteins (Yoshida et al., 2002). Originally described as a brain-enriched protein (Erhardt et al., 1998), Fbx2 is also highly expressed in the organ of Corti, in which it has been called organ of Corti protein 1 (Thalmann et al., 1997). Mice with targeted deletion ofFbxo2develop age-related hearing loss beginning at 2 months. Cellular degeneration begins in the epithelial support cells of the organ of Corti and is accompanied by changes in cellular membrane integrity and early increases in connexin 26, a cochlear gap junction protein previously shown to interact with Fbx2 (Henzl et al., 2004). Progressive degeneration includes hair cells and the spiral ganglion, but the brain itself is spared despite widespread CNS expression of Fbx2. Cochlear Fbx2 binds Skp1, the common binding partner for F-box proteins, and is an unusually abundant inner ear protein. Whereas cochlear Skp1 levels fall in parallel with the loss of Fbx2, other components of the canonical SCF (Skp1, Cullin1, F-box, Rbx1) ubiquitin ligase complex remain unchanged and show little if any complex formation with Fbx2/Skp1, suggesting that cochlear Fbx2 and Skp1 form a novel, heterodimeric complex. Our findings demonstrate that components of protein quality control are essential for inner ear homeostasis and implicate Fbx2 and Skp1 as potential genetic modifiers in age-related hearing loss.
Changes in Human Muscle Spindle Sensitivity during a Proprioceptive Attention Task
Authors: Hospod Valérie , Aimonetti Jean-Marc , Roll Jean-Pierre , Ribot-Ciscar Edith
Published: May 2007

The aim of the present study was to test whether fusimotor control of human muscle spindle sensitivity changed when attention was selectively directed to the recognition of an imposed two-dimensional movement in the form of a written symbol.

The unitary activities of 32 muscle spindle afferents (26 Ia, 6 II) were recorded by microneurography at the level of the common peroneal nerve. The patterns of firing rate in response to passive movements of the ankle, forming different letters or numbers, were compared in two conditions: control and recognition. No visual cues were given in either condition, but subjects had to recognize and name the character in one condition compared with not paying attention in the control condition.

The results showed that 58% of the tested Ia afferents presented modified responses to movements when these had to be recognized. Changes in Ia afferent responses included decreased depth of modulation, increased variability of discharge, and changes in spontaneous activity. Not all changes were evident in the same afferent. Furthermore, the percentage of correctly recognized movements amounted to 63% when changes were observed, but it was only 48% when the primary ending sensitivity was unaltered. The responses of group II afferents were only weakly changed or unchanged. It is suggested that the altered muscle spindle sensitivity is because of selective changes in fusimotor control, the consequence of which might be to feed the brain movement trajectory information that is more accurate.
p75 Neurotrophin Receptor Expression Defines a Population of BDNF-Responsive Neurogenic Precursor Cells
Authors: Young Kaylene M. , Merson Tobias D. , Sotthibundhu Areechun , Coulson Elizabeth J. , Bartlett Perry F.
Published: May 2007

Although our understanding of adult neurogenesis has increased dramatically over the last decade, confusion still exists regarding both the identity of the stem cell responsible for neuron production and the mechanisms that regulate its activity. Here we show, using flow cytometry, that a small population of cells (0.3%) within the stem cell niche of the rat subventricular zone (SVZ) expresses the p75 neurotrophin receptor (p75NTR) and that these cells are responsible for neuron production in both newborn and adult animals. In the adult, the p75NTR-positive population contains all of the neurosphere-producing precursor cells, whereas in the newborn many of the precursor cells are p75NTRnegative. However, at both ages, only the neurospheres derived from p75NTR-positive cells are neurogenic. We also show that neuron production from p75NTR-positive but not p75NTR-negative precursors is greatly enhanced after treatment with brain-derived neurotrophic factor (BDNF) or nerve growth factor. This effect appears to be mediated specifically by p75NTR, because precursor cells from p75NTR-deficient mice show a 70% reduction in their neurogenic potentialin vitroand fail to respond to BDNF treatment. Furthermore, adult p75NTR-deficient mice have significantly reduced numbers of PSA-NCAM (polysialylated neural cell adhesion molecule)-positive SVZ neuroblastsin vivoand a lower olfactory bulb weight. Thus, p75NTRdefines a discrete population of highly proliferative SVZ precursor cells that are able to respond to neurotrophin activation by increasing neuroblast generation, making this pathway the most likely mechanism for the increased neurogenesis that accompanies raised BDNF levels in a variety of disease and behavioral situations.
Motorcortical Excitability and Synaptic Plasticity Is Enhanced in Professional Musicians
Authors: Rosenkranz Karin , Williamon Aaron , Rothwell John C.
Published: May 2007

Musicians not only have extraordinary motor and sensory skills, but they also have an increased ability to learn new tasks compared with non-musicians. We examined how these features are expressed in neurophysiological parameters of excitability and plasticity in the motor system by comparing the results of 11 professional musicians and 8 age-matched non-musicians. Parameters of motor excitability were assessed using transcranial magnetic stimulation (TMS) to measure motor-evoked potentials (MEPs) together with recruitment of corticospinal projections [input–output curve (IOcurve)] and of short-latency intracortical inhibition (SICIcurve). Plasticity, here defined as change of synaptic effectiveness, was tested by measuring MEPs and IOcurves after paired associative stimulation (PAS), which consists of an electric median nerve stimulus repeatedly paired (200 times at 0.25Hz) with a TMS pulse over the hand motor area. Using an interstimulus interval of 25 ms (PAS25) or 10 ms (PAS10), this leads to long-term potentiation- or long-term depression-like plasticity, respectively. Musicians showed steeper recruitment of MEPs and SICI (IOcurve and SICIcurve). Additionally, PAS25 increased and PAS10 decreased the MEP amplitudes and the slope of the IOcurves significantly more in musicians than in non-musicians. This is consistent with a wider modification range of synaptic plasticity in musicians. Together with the steeper recruitment of corticospinal excitatory and intracortical inhibitory projections, this suggests that they regulate plasticity and excitability with a higher gain than normal. Because some of these changes depend on age at which instrumental playing commenced and on practice intensity, they may reflect an increase in number and modifiability of synapses within the motor area caused by long-term musical practice.
CHIP Overexpression Reduces Mutant Androgen Receptor Protein and Ameliorates Phenotypes of the Spinal and Bulbar Muscular Atrophy Transgenic Mouse Model
Authors: Adachi Hiroaki , Waza Masahiro , Tokui Keisuke , Katsuno Masahisa , Minamiyama Makoto , Tanaka Fumiaki , Doyu Manabu , Sobue Gen
Published: May 2007

Spinal and bulbar muscular atrophy (SBMA) is an inherited motor neuron disease caused by the expansion of a polyglutamine tract within the androgen receptor (AR). The pathologic features of SBMA are motor neuron loss in the spinal cord and brainstem and diffuse nuclear accumulation and nuclear inclusions of the mutant AR in the residual motor neurons and certain visceral organs. Many components of the ubiquitin-proteasome and molecular chaperones are also sequestered in the inclusions, suggesting that they may be actively engaged in an attempt to degrade or refold the mutant AR. C terminus of Hsc70 (heat shock cognate protein 70)-interacting protein (CHIP), a U-box type E3 ubiquitin ligase, has been shown to interact with heat shock protein 90 (Hsp90) or Hsp70 and ubiquitylates unfolded proteins trapped by molecular chaperones and degrades them. Here, we demonstrate that transient overexpression of CHIP in a neuronal cell model reduces the monomeric mutant AR more effectively than it does the wild type, suggesting that the mutant AR is more sensitive to CHIP than is the wild type. High expression of CHIP in an SBMA transgenic mouse model also ameliorated motor symptoms and inhibited neuronal nuclear accumulation of the mutant AR. When CHIP was overexpressed in transgenic SBMA mice, mutant AR was also preferentially degraded over wild-type AR. These findings suggest that CHIP overexpression ameliorates SBMA phenotypes in mice by reducing nuclear-localized mutant AR via enhanced mutant AR degradation. Thus, CHIP overexpression would provide a potential therapeutic avenue for SBMA.
Competitive Integration of Visual and Preparatory Signals in the Superior Colliculus during Saccadic Programming
Authors: Dorris Michael C. , Olivier Etienne , Munoz Doug P.
Published: May 2007

Efficient behavior requires that internally specified motor plans be integrated with incoming sensory information. Motor preparation and visual signals converge in the intermediate and deep layers of the superior colliculus (SC) to influence saccade planning and execution; however, the mechanism by which these sometimes conflicting signals are combined remains unclear. We studied this issue by presenting visual distractors as monkeys prepared saccades toward an upcoming target whose timing and location were fully predictable. Monkeys made more distractor-directed errors when the spatial location of visual distractors more closely coincided with the saccadic goal. Concomitant pretarget activity of SC visuomotor neurons, whose response fields were centered on the saccadic goal, was similarly increased by the presentation of nearby distractors and inhibited by the presentation of distant distractors. Finally, subthreshold microstimulation of the SC shifted the pattern of distractor-directed errors away from the saccadic goal toward that specified by the site of stimulation. Together, our results suggest that the likelihood of saccade generation is influenced by the spatial register of internal motor preparation signals and external sensory signals across the topographically organized SC map.
Interplay between Laminar Specificity and Activity-Dependent Mechanisms of Thalamocortical Axon Branching
Authors: Uesaka Naofumi , Hayano Yasufumi , Yamada Akito , Yamamoto Nobuhiko
Published: May 2007

Target and activity-dependent mechanisms of axonal branching were studied in the thalamocortical (TC) projection using organotypic cocultures of the thalamus and cortex. TC axons were labeled with enhanced yellow fluorescent protein (EYFP) by a single-cell electroporation method and observed over time by confocal microscopy. Changes in the firing activity of cocultures grown on multielectrode dishes were also monitored over time. EYFP-labeled TC axons exhibited more branch formation in and around layer 4 of the cortical explant during the second weekin vitro, when spontaneous firing activity increased in both thalamic and cortical cells. Time-lapse imaging further demonstrated that branching patterns were generated dynamically by addition and elimination with a bias toward branch accumulation in the target layer. To examine the relationship between neural activity and TC branch formation, the dynamics of axonal branching was analyzed under various pharmacological treatments. Chronic blockade of firing or synaptic activity reduced the remodeling process, in particular, branch addition in the target layer. However, extension of branches was not affected by this treatment. Together, these findings suggest that neural activity can modify the molecular mechanisms that regulate lamina-specific TC axon branching.
Distinctcis-Regulatory Elements from theDlx1/Dlx2Locus Mark Different Progenitor Cell Populations in the Ganglionic Eminences and Different Subtypes of Adult Cortical Interneurons
Authors: Ghanem Noël , Yu Man , Long Jason , Hatch Gary , Rubenstein John L. R. , Ekker Marc
Published: May 2007

Distinct subtypes of cortical GABAergic interneurons provide inhibitory signals that are indispensable for neural network function. TheDlxhomeobox genes have a central role in regulating their development and function. We have characterized the activity of threecis-regulatory sequences involved in forebrain expression of vertebrateDlxgenes: upstream regulatory element 2 (URE2), I12b, and I56i. The three regulatory elements display regional and temporal differences in their activities within the lateral ganglionic eminence (LGE), medial ganglionic eminence (MGE), and caudal ganglionic eminence (CGE) and label distinct populations of tangentially migrating neurons at embryonic day 12.5 (E12.5) and E13.5. We provide evidence that the dorsomedial and ventral MGE are distinct sources of tangentially migrating neurons during midgestation. In the adult cortex, URE2 and I12b/I56i are differentially expressed in parvalbumin-, calretinin-, neuropeptide Y-, and neuronal nitric oxide synthase-positive interneurons; I12b and I56i were specifically active in somatostatin-, vasoactive intestinal peptide-, and calbindin-positive interneurons. These data suggest that interneuron subtypes use distinct combinations ofDlx1/Dlx2enhancers from the time they are specified through adulthood.
Reversal of Synaptic Memory by Ca2+/Calmodulin-Dependent Protein Kinase II Inhibitor
Authors: Sanhueza Magdalena , McIntyre Charmian C. , Lisman John E.
Published: May 2007

Long-term potentiation (LTP) is an activity-dependent strengthening of synapses that is thought to underlie memory storage. Ca2+/calmodulin-dependent protein kinase II (CaMKII) has been a leading candidate as a memory molecule because it is persistently activated after LTP induction and can enhance transmission. Furthermore, a mutation that blocks persistent activation blocks LTP and forms of learning. However, direct evidence for a role of the kinase in maintaining synaptic strength has been lacking. Here, we show that a newly developed noncompetitive inhibitor of CaMKII strongly reduces synaptic transmission in the CA1 region of the hippocampal slice. This occurs through both presynaptic and postsynaptic action. To study the role of CaMKII in the maintenance of LTP, inhibitor was applied after LTP induction and then removed. Inhibition occurred in both LTP and control pathways but only partially recovered. The nonrecovering component was attributable primarily to a postsynaptic change. To test whether nonrecovery was attributable to a persistent reversal of LTP, we first saturated LTP and then transiently applied inhibitor. This procedure allowed additional LTP to be induced, indicating a reversal of an LTP maintenance mechanism. This is the first procedure that can reverse LTP by chemical means and suggests that a component of synaptic memory is attributable to CaMKII. The procedure also enhanced the LTP that could be induced in the control pathway, consistent with the idea that CaMKII is involved in controlling basal synaptic strength, perhaps as a result of LTP that occurredin vivo.
Rhythmic Episodes of Subthreshold Membrane Potential Oscillations in the Rat Inferior Olive NucleiIn Vivo
Authors: Chorev Edith , Yarom Yosef , Lampl Ilan
Published: May 2007

In vitrostudies of inferior olive neurons demonstrate that they are intrinsically active, generating periodic spatiotemporal patterns. These self-generated patterns of activity extend the role of olivary neurons beyond that of a deliverer of teaching or error signals. However, autorhythmicity or patterned activity of complex spikes in the cerebellar cortex was observed in only a few studies. This discrepancy between the self-generated rhythmicity in the inferior olive observedin vitroand the sporadic reports on rhythmicity of complex spikes can be reconciled by recording intracellularly from inferior olive neuronsin situ. To this end, we recorded intracellularly from olivary neurons of anesthetized rats. We demonstrate that,in vivo, olivary neurons show both slow and fast rhythmic processes. The slow process (0.2–2 Hz) is expressed as rhythmic transitions from quiescent periods to periods of fast rhythm, manifested as subthreshold oscillations of 6–12 Hz. Spikes, if they occur, are locked to the depolarized phase of these subthreshold oscillations and, therefore, hold and transfer rhythmic information. The transient nature of these oscillatory epochs accounts for the difficulties to uncover them by prolonged recordings of complex spikes activity in the cerebellar cortex.
A Liouville-type result for lacunary power series and converse results for universal holomorphic functions
Authors: Martirosian Valeri A. , Müller Jürgen
Published: May 2007

A Liouville-type result is proved for holomorphic functions having lacunary power series with restricted growth for a subsequence of the partial sums. As an application, converse results concerning existence of universal holomorphic functions are given.
A universal harmonic function which is bounded on each line
Authors: Kujat Irene
Published: May 2007

The aim of this note is the construction of harmonic functions which are bounded on each line L ⊂ R
The joint universality for periodic Hurwitz zeta-functions
Authors: Laurinčikas Antanas
Published: May 2007

We prove a joint universality theorem for the Hurwitz zeta-functions with periodic coefficients.
Condylar Asymmetry in Bilateral Posterior Crossbite Patients
Authors: Kiki Ali , Kılıç Nihat , Oktay Hüsamettin
Published: May 2007

Objective: To investigate whether patients with bilateral posterior crossbite have asymmetrically developed condyles.

Materials and Methods: The study group consisted of 75 patients with bilateral posterior crossbite, and a control group of 75 subjects with normal occlusion. Condylar, ramal, and condylar plus ramal asymmetry values were computed for all of the subjects on orthopantomograms. Data were analyzed statistically by means of paired t-test and Student's t-test.

Results: The patients with bilateral posterior crossbite had more asymmetrical condyles relative to the controls. However, there were no statistically significant differences in condylar, ramal, or condylar plus ramal heights between left and right sides in both the control and crossbite groups.

Conclusion: Patients with bilateral posterior crossbite can have asymmetrical condyles and might be at risk for the development of future skeletal mandibular asymmetries.
Effects of Self-Etching Primer on Shear Bond Strength of Orthodontic Brackets at Different Debond Times
Authors: Turk Tamer , Elekdag-Turk Selma , Isci Devrim
Published: May 2007

Objective: To evaluate the effect of a self-etching primer on shear bond strengths (SBS) at the different debond times of 5, 15, 30, and 60 minutes and 24 hours.

Materials and Methods: Brackets were bonded to human premolars with different etching protocols. In the control group (conventional method [CM]) teeth were etched with 37% phosphoric acid. In the study group, a self-etching primer (SEP; Transbond Plus Self Etching Primer; 3M Unitek, Monrovia, Calif) was applied as recommended by the manufacturer. Brackets were bonded with light-cure adhesive paste (Transbond XT; 3M Unitek) and light-cured for 20 seconds in both groups. The shear bond test was performed at the different debond times of 5, 15, 30 and 60 minutes and 24 hours.

Results: Lowest SBS was attained with a debond time of 5 minutes for the CM group (9.51 MPa) and the SEP group (8.97 MPa). Highest SBS was obtained with a debond time of 24 hours for the CM group (16.82 MPa) and the SEP group (19.11 MPa). Statistically significant differences between the two groups were not observed for debond times of 5, 15, 30, or 60 minutes. However, the SBS values obtained at 24 hours were significantly different (P < .001).

Conclusions: Adequate SBS was obtained with self-etching primer during the first 60 minutes (5, 15, 30 and 60 minutes) when compared with the conventional method. It is reliable to load the bracket 5 minutes after bonding using self-etching primer (Transbond Plus) with the light-cure adhesive (Transbond XT).
Effects of Growth Hormone on Craniofacial Growth
Authors: Funatsu Minayo , Sato Koshi , Mitani Hideo
Published: May 2007

Objective: This study determined the effects of growth hormone (GH) therapy on craniofacial growth in idiopathic growth hormone deficiency (GHD).

Materials and Methods: Fifty-seven patients (33 boys and 24 girls; age range 4.5 to 16.7 years) with GHD were investigated and categorized into three groups according to the duration of GH therapy: the untreated group, the short-term therapy group, and the long-term therapy group. Their lateral cephalometric radiographs were studied, and craniofacial measurements were assessed by age and sex by using matched standard deviation scores.

Results: In the untreated group, the anterior cranial base, total facial height, maxillary length, mandibular total length, mandibular body length, and ramus height were smaller than the standard values. In comparison with the untreated group, the long-term therapy group had a significantly larger upper facial height (P < .05), maxillary length (P < .01), and ramus height (P < .01) measurements.

Conclusions: Children who received long-term GH replacement therapy showed increased growth of the craniofacial skeleton, especially the maxilla and ramus. These findings suggest that GH accelerates craniofacial development, which improves occlusion and the facial profile.
Evaluation of Force Degradation Characteristics of Orthodontic Latex Elastics in Vitro and In Vivo
Authors: Wang Tong , Zhou Gang , Tan Xianfeng , Dong Yaojun
Published: May 2007

Objective: To evaluate the characteristics of force degradation of latex elastics in clinical applications and in vitro studies.

Materials and Methods: Samples of 3/16-inch latex elastics were investigated, and 12 students between the ages of 12 and 15 years were selected for the intermaxillary and intramaxillary tractions. The elastics in the control groups were set in artificial saliva and dry room conditions and were stretched 20 mm. The repeated-measure two-way analysis of variance and nonlinear regression analysis were used to identify statistical significance.

Results: Overall, there were statistically significant differences between the different methods and observation intervals. At 24- and 48-hour time intervals, the force decreased during in vivo testing and in artificial saliva (P < .001), whereas there were no significant differences in dry room conditions (P > .05). In intermaxillary traction the percentage of initial force remaining after 48 hours was 61%. In intramaxillary traction and in artificial saliva the percentage of initial force remaining was 71%, and in room conditions 86% of initial force remained. Force degradation of latex elastics was different according to their environmental conditions. There was significantly more force degradation in intermaxillary traction than in intramaxillary traction. The dry room condition caused the least force loss.

Conclusions: There were some differences among groups in the different times to start wearing elastics in intermaxillary traction but no significant differences in intramaxillary traction.
The Success of Orthodontic Satellite Practices
Authors: Heying Scott S. , English Jeryl D. , Bussa Henry I. , Corbett John A.
Published: May 2007

Objective: To evaluate the financial success and personal satisfaction of orthodontists operating satellite practices.

Materials and Methods: A questionnaire was e-mailed to 4426 members of the American Association of Orthodontists (AAO), and 817 completed surveys were returned, yielding an 18% response rate. Only replies from solo practitioner orthodontists were analyzed to limit variability among respondents.

Results: Solo practitioner orthodontists with satellite practices reported an increase in net profit and started significantly more cases than orthodontists with one office. Yet, only 27% of respondents with one satellite and 48% of practitioners operating multiple satellites recommend opening a satellite practice. Ninety-two percent of orthodontists stated they were satisfied with the clinical aspects of their practice, and 99% of orthodontists described themselves as happy and satisfied individuals.

Conclusion: Despite the ability of a satellite office to expand a patient base and increase net income, most practitioners would not encourage young orthodontists to establish a satellite office.
Treatment and Posttreatment Changes with Combined Headgear Therapy
Authors: Tortop Tuba , Yüksel Sema
Published: May 2007

Objective: To determine the effects of combined headgear treatment in high-angle patients and to evaluate the differences 2 years after treatment.

Materials and Methods: The study material consisted of lateral cephalograms of 21 patients (13 girls and eight boys; mean age 10 years 3 months) with Class II dental relationship. Only extraoral combined traction that was applied to maxillary first molars was used in the treatment of all patients. The patients were instructed to wear the appliance 20 hours per day until the molar relationship was corrected. The treatment time was approximately 5 months. At the beginning (T0), at the end (T1), and approximately 2 years after (T2) combined headgear treatment, lateral cephalometric radiographs were obtained.

Results: SNA and ANB angles and convexity decreased significantly during treatment (T0–T1; P < .05 and P < .01, respectively), and the net changes (T0–T2) in ANB angle and convexity were also found to be statistically significant (P < .01). During treatment, significant distal movement was found in the upper first molar, and the second premolar and molar were also distalized significantly (P < .001). At the end of 2 years, there was a significant mesial migration of the upper molars and the second premolar during the posttreatment period, but all of them were positioned more distally compared to the beginning of treatment (P < .001). The decrease in molar relation was statistically significant during the T0–T1 and T0–T2 periods (P < .001).
Perception of Occlusion, Psychological Impact of Dental Esthetics, History of Orthodontic Treatment and Their Relation to Oral Health in Naval Recruits
Authors: Klages Ulrich , Rost Felix , Wehrbein Heinrich , Zentner Andrej
Published: May 2007

Objective: To investigate whether the oral health of young male adults was related to (1) the degree of self-perceived malocclusion, (2) the degree of experienced negative psychosocial impact of dental esthetics, and (3) the history of orthodontic treatment and its duration.

Materials and Methods: The study subjects were 470 male naval recruits undergoing a routine dental health checkup. They answered the Perception of Occlusion Scale (POS) and Negative Impact of Dental Aesthetics Scale (NIDAS). The Approximal Plaque Index (API), the Sulcus Bleeding Index (SBI), and the number of decayed teeth (DT) and missing teeth (MT) were examined by a staff dentist. Statistical procedures were one-way analyses of variance in the API and SBI and nonparametric Kruskal-Wallis, Mann-Whitney, and χ2 tests in DT and MT as dependent variables.

Results: (1) The subjects ranging within the upper POS quartile scored higher on the SBI (contrast: P = .003) and DT (P = .002) than did those in the lower POS quartiles. (2) In contrast to the subjects reporting minor negative impacts in the NIDAS, those with strong impacts had higher scores on the API and MT (each P < .001). (3) In the subjects with a history of orthodontic treatment lasting 30 months and longer, lower API (P < .05), SBI and DT (each P = .002), and MT (P = .007) scores were found than in the subjects without previous orthodontic treatment.

Conclusion: The results suggest that self-perceived dental irregularity and negative impact of dental esthetics might affect oral health, whereas previous extensive orthodontic treatment may have favorable effects by improving dental health compliance.
Treatment and Posttreatment Effects of Quad-Helix/Crib Therapy of Dentoskeletal Open Bite
Authors: Cozza Paola , Mucedero Manuela , Baccetti Tiziano , Franchi Lorenzo
Published: May 2007

Objective: To investigate the effects of the quad-helix/crib (Q-H/C) appliance in subjects with thumb-sucking habits and dentoskeletal open bite at 2 years after the end of active treatment.

Materials and Methods: The records of 21 subjects treated with the Q-H/C appliance were compared with a control group of 21 untreated subjects with similar vertical relationships. Lateral cephalograms were obtained before treatment (T1; mean age 8.4 ± 1.4 years) and at about 2 years after treatment (T2; mean age 11.7 ± 1.9 years) and analyzed. Mean treatment duration was 1.5 years ± 7 months. The T2–T1 changes in the two groups were compared with a nonparametric test for independent samples.

Results: The mean increase in overbite during Q-H/C therapy (4.1 mm) represented an overcorrection of the amount of anterior open bite at T2. Both the maxillary and mandibular incisors showed significantly greater extrusion in the Q-H/C group than in the control group. The treated group showed a greater downward rotation (1.8°) of the palatal plane than did the control group. This change was associated with a clinically significant reduction in the palatal plane/mandibular plane angle (−2.5°) in the Q-H/C group. The upper lip showed significant retraction relative to the E-plane in the treated group (3.6 mm) compared with the controls.

Conclusions: The Q-H/C appliance was effective in correcting dental open bite in 85% of the growing subjects with thumb-sucking habits and dentoskeletal open bites. Correction of anterior open bite was associated with a clinically significant improvement in maxillomandibular vertical skeletal relationships.
Long-term Failure Rate of Brackets Bonded with Plasma and High-intensity Light-emitting Diode Curing Lights
Authors: Pandis Nikolaos , Strigou Sophia , Eliades Theodore
Published: May 2007

Objective: To comparatively assess the long-term failure rate of brackets bonded with a plasma or a high-intensity light-emitting diode (LED) curing light.

Materials and Methods: Twenty-five patients with complete permanent dentitions with similar treatment planning and mechanotherapy were selected for the study. Brackets were bonded according to a split-mouth design with the 3M Ortholite Plasma or the high-power Satelec mini LED Ortho curing light. Irradiation with the two curing lights was performed for 9 seconds at an alternate quadrant sequence so that the bonded brackets cured with either light were equally distributed on the maxillary and mandibular right and left quadrants. First-time bracket failures were recorded for a mean period of 15 months (range 13–18 months) and the results were analyzed with the chi-square test and binary logistic regression.

Results: The failure rate for brackets was 2.8% for the plasma light and 6.7% for the LED light source. Although significantly more failures were found for the mandibular arch, no difference was identified in failure rate between anterior and posterior teeth.

Conclusions: High-intensity LED curing lights present a 2.5 times higher failure rate relative to plasma lamps for nominally identical irradiation time. Mandibular teeth show almost 150% higher failure incidence compared with maxillary teeth. No effect from the arch side (right vs left) and location (anterior vs posterior) was identified in this study.
Surface Conditioning Methods and Polishing Techniques Effect on Surface Roughness of a Feldspar Ceramic
Authors: Saraç YŞinasi , Elekdag-Turk Selma , Saraç Duygu , Turk Tamer
Published: May 2007

Objective: To investigate the effects of three surface conditioning methods on shear bond strength (SBS) and on surface roughness (Ra) of a feldspathic ceramic, and to compare the efficiency of three polishing techniques.

Materials and Methods: A total of 106 feldspathic specimens were used. Thirty specimens were divided into three groups according to the surface conditioning methods: air-particle abrasion (APA) with 25-μm aluminum trioxide (Al2O3) (group A); hydrofluoric acid (HFA) (group H); APA and HFA (group AH). Metal brackets were bonded and subjected to SBS testing. Sixty-three specimens were divided into three groups according to the surface conditioning method. Ra was evaluated profilometrically. Then, each group was divided into three subgroups according to the polishing technique, ie, adjustment kit, diamond polishing paste, adjustment kit + diamond polishing paste. Following polishing, the second Ra values were obtained.

Results: The lowest SBS was obtained for group H. This value was significantly different from the values of groups A and AH (P < .05). The lowest Ra value was observed for group H (P < .001). There was no significant difference between groups A and AH (P > .05). No significant differences between the subgroups in which a polishing paste was used were observed (P > .05). There was no significant difference between the adjustment kit and the adjustment kit + a diamond polishing paste (P > .05).

Conclusion: APA or APA + HFA created rougher porcelain surfaces than HFA alone. Both adjustment kit use and the adjustment kit + polishing paste application were effective to smooth the porcelain, but one was not found superior to the other.