bluuebunny/crossref_metadata_2025_split huggingface dataset:
Change in Component Proteins of the Egg Envelope (Chorion) of Rainbow Trout during Hardening
Authors: Luchi Ichiro , Masuda Kaori , Yamagami Kenjiro 
Published: January 2005

Egg envelope (chorion) of unfertilized eggs of rainbow trout, Oncorhynchus mykiss, consists of 4 major protein components whose molecular weights are approximately 110 K, 64 K, 56 K and 50 K. On hardening of the chorion after activation, 64 K, 56 K and 50 K components disappeared, some components higher than 160 K were newly formed and the solubility of the chorion in 1 N NaOH or 12 M urea‐2% SDS‐1% 2‐mercaptoethanol (Sample Buffer) decreased. This implies that probable formation of covalent crosslinks between the constituents occurs during the hardening.Hardening occurred also in the chorion isolated from the unfertilized eggs. The conversion of the 64 K, 56 K and 50 K components into the higher molecular weight intermediates was Ca2+‐dependent, accelerated by 2‐mercaptoethanol and inhibited by a high temperature (60°C). Optimum pH of this hardening system was acidic, i.e., 5.0 to 6.0.Cadaverine inhibited the change in solubility of chorion in NaOH or Sample Buffer, while it could not inhibit the disappearance of the 64 K, 56 K and 50 K components and the new formation of the higher molecular weight intermediates. This observation indicates existence of two processes in chorion hardening, which are tentatively named cadaverine‐insensitive and cadaverine‐sensitive processes.
Change in Intracellular Calcium Ions upon Maturation in Starfish Oocytes
Authors: Kikuyama Munehiro , Hiramoto Yukio 
Published: January 2005

A transient increase in intracellular Ca2+ upon maturation in starfish oocyte was revealed by light emission of aequorin microinjected into the cell. One minute application of 1‐methyladenine (1‐MeAde) to a limited area of the oocyte surface was sufficient to induce the Ca2+ transient over the entire cell though it did not induce the germinal vesicle breakdown (GVBD). Ten minutes application of 1‐MeAde induced a similar Ca2+ transient followed by GVBD. Even when the transient increase of Ca2+ was inhibited by injecting EGTA into the oocyte, 1‐MeAde treatment for a long period induced GVBD. These facts indicate that the Ca2+ increase is neither necessary nor sufficient for maturation of the starfish oocyte.When the oocyte, which had been treated with 1‐MeAde for 1 min at a limited area around the animal pole, was treated again with 1‐MeAde for 10 min starting about 15 min after the first treatment, a Ca2+ transient similar to the first one was induced and was followed by GVBD. By contrast, in the oocyte treated with 1‐MeAde at an area around the vegetal pole, neither Ca2+ transient nor GVBD was induced by the second treatment with 1‐MeAde. These results indicate a difference in responsiveness to the hormone between the animal hemisphere and the vegetal hemisphere of the oocyte.
The Loss of the Expression of α Catenin, the 102 kD Cadherin Associated Protein, in Central Nervous Tissues during Development
Authors: Nagafuchi Akira , Tsukita Shoichiro 
Published: January 2005

A monoclonal antibody specific for α catenin, the 102kD cadherin‐associated protein, has been characterized and used to describe the expression and distribution pattern of α catenin in adult mice and mouse embryos. This monoclonal antibody recognized an epitope in the middle part of the α catenin molecule of various vertebrate species, and bound to neither vinculin nor αN catenin, which are cytoskeletal proteins with sequence similarity to α catenin. At the early mouse embryo stage (neurulae stage) α catenin was expressed and concentrated at cell‐to‐cell contact sites together with various types of cadherins in all tissues. In embryos at 12.5 days of gestation, the α catenin expression was gradually diminished selectively in central nervous tissues such as brain and spinal cord, and in most of the adult central nervous tissues the α catenin expression was hardly detected. In adult non‐nervous tissues most of the cells examined expressed α catenin. Especially in well‐polarized tissues such as epithelial cells, α catenin appeared to be highly concentrated at cell‐to‐cell adherens junctions where cadherins act as adhesion molecules.This loss of α catenin expression in central nervous tissues was observed not only in mice but also in other vertebrate species such as fish and newt, suggesting that this phenomenon has important implications from the view point of nervous tissue development.
An Ultrastructural Investigation on Vitellophage Invasion of the Yolk Mass during and after Germ Band Formation in Embryos of the Stick Insect Carausius morosus Br.
Authors: Fausto Anna Maria , Carcupino Marcella , Mazzini Massimo , Giorgi Franco 
Published: January 2005

Developing embryos of the stick insect Carausius morosus were examined ultrastructurally with a view to studying vitellophage invasion of the yolk mass during and after germ band formation. Newly laid eggs in C.morosus have a unique yolk fluid compartment surrounded by a narrow fringe of cytoplasm comprising several small yolk granules. Vitellophages originate mainly from a thin layer of stem cells, the so‐called yolk cell membrane, interposed between the germ band and the yolk mass. Throughout development, a thin basal lamina separates the yolk cell membrane from the overlying embryo.Vitellophages extend from the yolk cell membrane with long cytoplasmic processes or filopodia to invade the central yolk mass. Along their route of entrance, filopodia engulf portions of the yolk mass and sequester it into membrane‐bounded granules. As this process continues, the yolk mass is gradually partitioned into a number of yolk granules inside the vitellophages.Later in development, the yolk cell membrane is gradually replaced by the endodermal cells that emerge from the anterior and posterior embryonic rudiments. From this stage of development onwards, vitellophages remain attached to the basal lamina through long filopodia extending between the endodermal cells. Yolk confined in different vitellophagic cells appears heterogeneous both in density and texture, suggesting that yolk degradation may be spatially differentiated.
Effects of K+ and the K+ Ionophore Valinomycin on the Post‐Conjugational Nuclear Differentiation of Paramecium caudatum
Authors: Mikami Kazuyuki , Ohtsu Rie 
Published: January 2005

For determination of the effect of K+ on macro‐ and micronuclear differentiation Paramecium caudatum exconjugants were transferred to medium with various concentrations of Valinomycin and/or K+ at the critical stage of nuclear differentiation. The differentiation was not disturbed by transfer to medium containing 1.5 mM to 50 mM KCl. Injection of KCl solution at the critical stage also did not affect differentiation of the macronucleus appreciably. But change of the KCl concentration in the medium at the critical stage interrupted of normal development of the macronucleus.Macro‐ and micronuclear differentiations after conjugation are known to be determined by the antero‐posterior localization of postzygotic micronuclei. This nuclear localization is achieved by elongation of mitotic spindles and marked shortening of the cell length at the time of micronuclear division. Successive measurements of cell length at 25°C showed that cells began to shorten 1.5 hr after mating‐pair separation, reaching to half the initial length about 2.5 hr after the separation, and then returning to recover their initial length within about 50 min. In a solution of K+ (50 mM) plus Valinomycin (1μg/ml or more), cell shortening was inhibited. It is not known whether elongation of mitotic spindles at the time of critical nuclear division was disordered by this treatment, but the macronuclear anlagen developed in the treated cells. Thus shortening in the cell length is not indispensable for nuclear differentiation.
Transient Calretinin Expression during Intervertebral Disc Formation of the Chick Embryo
Authors: Gangji Valérie , Bastianelli Enrico , Rooze Marcel , Pochet Roland 
Published: January 2005

Calretinin immunoreactivity was localized during chick embryonic cervical spine development from day 4 until day 16. A transitory expression of calretinin could be seen from embryonic day 5 to embryonic day 15 in the mesenchymal cells forming the intervertebral disc. Calretinin was most abundant at embryonic day 8 when a maximal proliferation of cells occurred.At embryonic day 12, calretinin positive fibroblasts were located along the fibers forming the annulus fibrosus. At embryonic day 16, calretinin immunoreactivity could no more be detected in the cervical column. In conclusion, an intracellular calcium binding proteins belonging to the calmodulin/troponin C superfamily, appeared to be a marker for the disc formation.
Corrected Structure of the 5′ Flanking Region of Arylsulfatase Gene of the Sea Urchin, Hemicentrotus pulcherrimus
Authors: Akasaka Koji , Sakamoto Naoaki , Yamamoto Takashi , Morokuma Junji , Fujikawa Nobuhisa , Takata Kazuko , Eguchi Sachiko , Shimada Hiraku 
Published: January 2005

The nucleotide sequence of the 5′ flanking region of the arylsulfatase (Ars) gene of the sea urchin, Hemicentrotus pulcherrimus, is extensively corrected. The one previously reported from our laboratory (ref. 7, Develop, Growth & Differ., 34, 719–729, 1992) contains many sequencing errors and should be replaced with that presented here. Correction includes the addition of a 294 nucleotide (nt) sequence between −728 and −1,021. In the previous sequencing, this fragment was missed by overlooking one Hindlll site during subcloning.In addition to a cluster of direct repeats between −2,592 and −3,440, an inverted repeat is detected between −217 and −476. A possible role of the inverted repeat in the regulation of transcription of the Ars gene is discussed.
Sensory and cognitive mechanisms for preattentive change detection in auditory cortex
Authors: Opitz B. , Schröger E. , Von Cramon D. Yes 
Published: January 2005

AbstractIn order to react adequately to potentially relevant information outside the focus of attention, our brain preattentively scans the acoustic environment for irregularities. Two different mechanisms are currently discussed: (i) a sensory one based on differential states of refractoriness of neurons sensitive to the features of a regular event and of neurons sensitive to features of an irregular event; (ii) a cognitive one based on a comparison of short‐lived memory representations encoding current stimulation and the invariance inherent in recent recurrent stimulation. Here, we identified regions that mediate either of the two mechanisms by combining functional magnetic resonance imaging with an experimental protocol controlling for refractoriness. The sensory mechanism was associated with activity in the primary auditory cortex, whereas the cognitive one revealed activity in nonprimary auditory areas in the anterior part of Heschl's Gyrus. Moreover, it turned out that in the traditional oddball paradigm both mechanisms contribute to irregularity detection.
Denervation‐induced alterations in gene expression in mouse skeletal muscle
Authors: Magnusson Caroline , Svensson Anna , Christerson Ulrika , Tågerud Sven 
Published: January 2005

AbstractMotoneurons are important for regulating the function and properties of skeletal muscle. In the present study high‐density oligonucleotide arrays have been used to compare gene expression in innervated and six‐days denervated NMRI mouse skeletal muscle. To avoid looking at genes mainly participating in the process of atrophy, both hind‐limb muscles (atrophic after denervation) and hemidiaphragm muscle (transiently hypertrophic after denervation) were used. Only genes previously not known to respond to denervation and with potential roles in DNA/RNA interactions/transcription and/or cellular communication/signalling are presented. Data for additional genes are provided as supplementary material. Thirty‐two genes, up‐regulated by a factor of two or down‐regulated to the same extent after denervation, are presented. These include genes that may act through chromatin remodelling and/or as transcription factors/regulators (Cdkn1a, Cdr2, Hrmt1l2, Idb2, Myc/c‐myc, L‐myc1, Rb1, Sap30 and Tgif), genes possibly involved in the regulation of muscle membrane properties and/or excitation‐contraction coupling (Cacng1, Camk2d, Hrmt1l2, Kcnj12, Kcna7 and Rrad) and genes potentially involved in neuromuscular interactions and/or receptor signalling (Acvr2b, Adam19, D0H4S114, Kai1, Maged1, Mt2, Prkcabp, Ptp4a3, Ramp1, Rras, Timp1, Vegfa and Zfp145). A set of five genes with altered expression after denervation (Fzd9, Nr4a1, Frat2, Ctgf and Cyr61) indicate that Wnt signalling may be reduced in denervated skeletal muscle.
Specific pathophysiological functions of JNK isoforms in the brain
Authors: Brecht Stephan , Kirchhof Rainer , Chromik Ansgar , Willesen Mette , Nicolaus Thomas , Raivich Gennadij , Wessig Jan , Waetzig Vicki , Goetz Mario , Claussen Malte , Pearse Damien , Kuan Chia‐Yi , Vaudano Elisabetha , Behrens Axel , Wagner Erwin , Flavell Richard A. , Davis Roger J. , Herdegen Thomas 
Published: January 2005

AbstractWe have investigated the effect of JNK1 ko, JNK2 ko, JNK3 ko, JNK2+3 ko and c‐JunAA mutation on neuronal survival in adult transgenic mice following ischemia, 6‐hydroxydopamine induced neurotoxicity, axon transection and kainic acid induced excitotoxicity. Deletion of JNK isoforms indicated the compartment‐specific expression of JNK isoforms with 46‐kDa JNK1 as the main phosphorylated JNK isoform. Permanent occlusion of the MCA significantly enlarged the infarct area in JNK1 ko, which showed an increased expression of JNK3 in the penumbra. Survival of dopaminergic neurons in the substantia nigra compacta (SNC) following intrastriatal injection of 6‐hydroxydopamine was transiently improved in JNK3 ko and c‐JunAA mice after 7 days, but not 60 days. Following transection of the medial forebrain bundle, however, JNK3 ko conferred persisting neuroprotection of axotomised SNC neurons. None of the JNK ko and c‐JunAA mutation affected the survival of facial motoneurons following peripheral axotomy when investigated after 90 days. Finally, we determined the impact of JNK ko on the survival of animals and the degeneration of hippocampal neurons following kainic acid. JNK3 ko mice were substantially resistant against and survived kainic acid‐induced seizures. JNK3 ko and JNK1 ko showed a nonsignificant tendency for decreased or increased death of hippocampal neurons, respectively. Surprisingly, the deletion of a single JNK isoform did not attenuate the immunocytochemical signal of phosphorylated c‐Jun irrespective on the experimental set‐up. This comprehensive study provides novel insights into the context‐dependent physiological and pathological functions of JNK isoforms.
sgk1, a member of an RNA cluster associated with cell death in a model of Parkinson's disease
Authors: Stichel Christine C. , Schoenebeck Bodo , Foguet Montserrat , Siebertz Barbara , Bader Verian , Zhu Xin Ran , Lübbert Hermann 
Published: January 2005

AbstractIn an effort to gain deeper insight into the molecular processes underlying neurodegeneration in Parkinson's disease, we performed gene expression profiling at several early time points after MPTP‐injection into old (1‐year) mice. We used a PCR‐based gene expression profiling method, digital expression pattern display (DEPD), a method of very high sensitivity and reproducibility, which displays almost all transcripts of a tissue. To identify cell death‐associated genes, we defined clusters of differentially expressed transcripts with expression behaviour that correlated with the temporal profile of cell death progression and characterized one of these cell death clusters further. We selected one of the strongest regulated genes, the serum and glucocorticoid‐regulated kinase 1 (sgk1), and validated its differential expression by Northern blot analysis, semiquantitative PCR and in situ hybridization. Up‐regulation of sgk1 (i) coincides with the onset of dopaminergic cell death in both the 8‐week acute and 1‐year subacute MPTP models, (ii) spans the entire brain, (iii) is attenuated by the l‐deprenyl‐mediated inhibition of the MPTP conversion to its active metabolite MPP+ and (iv) is not induced by dehydration. This study demonstrated that the combination of the DEPD technology, clustering analysis and a detailed histopathology is a useful tool for elucidating molecular pathways in neurodegenerative diseases.
Dynamics of olfactory learning‐induced up‐regulation of L1 in the piriform cortex and hippocampus
Authors: Knafo Shira , Barkai Edi , Libersat Frederic , Sandi Carmen , Venero César 
Published: January 2005

AbstractL1 is a cell adhesion molecule implicated in the formation of neural circuits and synaptic plasticity. We have examined the sequence and time‐frame in which modifications in the synaptic expression of L1 occur in the piriform cortex and hippocampus in the course of rule learning of an olfactory discrimination task. Rats were trained to choose the correct odour in a pair to be rewarded with drinking water. Such training requires 6–8 days on average before rats reach maximal performance. We observed a learning‐induced L1 up‐regulation that occurred at an early training stage in the piriform cortex but only after rule‐learning establishment in the hippocampus. We suggest that the dynamics of L1 up‐regulation may reflect the functional role of these brain regions in olfactory rule learning.
Static and dynamic properties of vergence‐induced reduction of ocular counter‐roll in near vision
Authors: Mandelli M.‐J. , Misslisch H. , Hess B. J. M. 
Published: January 2005

AbstractWe have examined the characteristics of vergence‐induced reduction of ocular counter‐roll in near vision. Monkeys were trained to make convergent and divergent refixations with the head and body either upright or in various roll orientations. During near viewing requiring 17° horizontal vergence, we found that static binocular torsion was suppressed by about 68% (averaged over both eyes, two monkeys and both near target locations). This result is in accordance with a previous study in which binocular torsion was quantified based on the displacement planes of eye positions in far and near viewing. Latency and duration of the change in torsional eye position depended (for each eye differently) on body roll and the depth plane of fixation. For instance, during convergent refixations in left‐ear‐down orientations, the latencies of the left eye were smaller and the durations were longer than those of the right eye. However, both eyes reached their final positions required to fixate the second visual target at roughly the same time. The different dynamics of the two eyes is explained by the fact that each eye rotated temporally when the eyes converged, a pattern named binocular extension of Listing's law. Coming from or aiming at a common torsional value (normal ocular counter‐roll) in convergent or divergent refixations, the required torsion differs in the two eyes. The brain compensates for these differences by adjusting the dynamics of each eye's movement.
Pharmacological antagonism of metabotropic glutamate receptor 1 regulates long‐term potentiation and spatial reference memory in the dentate gyrus of freely moving rats via N‐methyl‐d‐aspartate and metabotropic glutamate receptor‐dependent mechanisms
Authors: Naie Katja , Manahan‐Vaughan Denise 
Published: January 2005

AbstractGroup I metabotropic glutamate receptors (mGluRs) are critically required for multiple forms of hippocampal synaptic plasticity in vivo. The role of the receptor subtype mGluR1 in long‐term potentiation (LTP) and learning is unclear. We examined the contribution of mGluR1 to hippocampal LTP and spatial learning using the selective antagonist (S)‐(+)‐α‐amino‐4carboxy‐2‐methylbenzene‐acetic acid (LY367385). Male Wistar rats were chronically implanted with recording and stimulating electrodes to enable measurement of evoked potentials from medial perforant path–dentate gyrus granule cell synapses. An injection cannula was inserted into the ipsilateral cerebral ventricle to enable drug application. Experiments were begun 10 days after the implantation procedure. We induced a robust LTP which lasted over 25 h with a 200‐Hz tetanization. Injections of LY367385 at all concentrations under investigation (4–32 nmol in a 5‐µL injection volume) did not affect basal synaptic transmission. In contrast, we observed a dose‐dependent impairment of LTP expression: LY367385 (4 nmol) had no effect on LTP induction, whereas 8 and 16 nmol LY367385 reduced both LTP induction and expression, suggestive of an interaction with N‐methyl‐d‐aspartate receptors. We assessed the effects of daily LY367385 application (8 nmol) on performance in an eight‐arm radial maze. LY367385‐treated rats showed deficits in reference but not working memory performance compared with vehicle‐treated controls. Rearing, grooming and locomotor activity were unaffected by LY367385. These data suggest an important role for mGluR1 in LTP and learning and highlight the specific significance of this mGluR subtype for reference memory.
Inhibition of the central extended amygdala by loud noise and restraint stress
Authors: Day Heidi E. W. , Nebel Scott , Sasse Sarah , Campeau Serge 
Published: January 2005

AbstractIt is well established that the central nucleus of the amygdala (CEA) is involved in responses to stress, fear and anxiety. Many studies have used c‐fos expression to map the brain's response to processive stress, but curiously the CEA generally is not highly activated. We have previously shown that exposure to a novel vs. home environment reduces amphetamine‐induced activation of the lateral CEA (CEAl) and the oval nucleus of the bed nucleus of the stria terminalis (BSTov). This is consistent with the idea that processive stress inhibits neurons in these nuclei. We have tested this hypothesis by exposing rats to noise, at a range of intensities from non‐stressful to stressful, or to restraint conditions, immediately after a remote injection of amphetamine, 2 mg/kg i.p., or interleukin‐1β (IL‐1β) 0.5 µg/kg i.p. (used to obtain a level of c‐fos mRNA against which to measure inhibition). In keeping with our hypothesis, amphetamine‐ or IL‐1β‐induced c‐fos and zif‐268 mRNA were significantly decreased in the CEAl and BSTov under conditions of loud noise or restraint stress compared with control conditions. This inhibition does not require a stress‐induced rise in corticosterone because data were similar in animals that had been adrenalectomized with a low‐dose corticosterone replacement. As both the CEAl and BSTov are highly γ‐aminobutyric acid (GABA) ‐ergic and project to the medial CEA (CEAm), their inhibition potentially causes an increased input to the CEAm. As the CEAm is a major output nucleus of the amygdala, this could have important consequences within the neural circuitry controlling responses to processive stress.