bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reaction of spinal cord central canal cells to cord transection and their contribution to cord regeneration
Authors: Dervan Adrian G. , Roberts Barry L. 
Published: March 2003

AbstractAfter transection, the spinal cord of the eel Anguilla quickly regrows and reconnects, and function recovers. We describe here the changes in the central canal region that accompany this regeneration by using serial semithin plastic sections and immunohistochemistry. The progress of axonal regrowth was followed in material labeled with DiI. The canal of the uninjured cord is surrounded by four cell types: S‐100‐immunopositive ependymocytes, S‐100‐ and glial fibrillary acidic protein (GFAP)‐immunopositive tanycytes, vimentin‐immunopositive dorsally located cells, and lateral and ventral liquor‐contacting neurons, which label for either γ‐aminobutyric acid (GABA) or tyrosine hydroxylase (TH). After cord transection, a new central canal forms rapidly as small groups of cells at the leading edges of the transection create flat “plates” that serve as templates for subsequent formation of the lateral and dorsal walls. Profile counts and 5‐bromo‐2′‐deoxyuridine immunohistochemistry indicate that these cells are dividing rapidly during the first 20 days of the repair process. The newly formed canal, which bridges the transection by day 10 but is not complete until about day 20, is greatly enlarged (≤100 times) and is dominated by ependymocytes that are vimentin immunopositive, but cells expressing GABA, TH, and GFAP do not appear until days 11, 13, and 16, respectively. The proliferating ependyma do not provide a supportive scaffold for the regrowing axons, inasmuch as some have crossed the bridge before the canal has formed. However, their modified phenotype suggests a role, possibly trophic, for the central canal region following injury. J. Comp. Neurol. 458:293–306, 2003. © 2003 Wiley‐Liss, Inc.
Dendritic orientation and laminar architecture in the rabbit auditory thalamus
Authors: Cetas Justin S. , Price Robin O. , Crowe Jennifer , Velenovsky David S. , McMullen Nathaniel T. 
Published: March 2003

AbstractA laminar organization composed of the dendritic fields of principal neurons and afferent axonal arbors has been proposed as the anatomical substrate for the frequency map at several levels of the mammalian central auditory system, including the inferior colliculus and medial geniculate body (MGB). In contrast to the auditory thalamus in most mammals, the ventral division of the rabbit medial geniculate body (MGV) has cellular laminae visible in routine Nissl stains, allowing a direct comparison of the laminar organization with the dendritic architecture and frequency organization. In total 30 presumptive relay neurons in the MGV were labeled with the juxtacellular recording method, and their dendritic arbors were fully reconstructed from serial sections with the aid of a computer microscope. The spatial organization of MGV dendritic fields was analyzed using the dendritic prism, dendritic stick, and fan‐in projection methods. Quantitative spatial analyses revealed that, for MGV neurons in the central pars lateralis subdivision, the major axis of the dendritic fields (∼29° relative to the horizontal plane) was closely aligned with that of the Nissl laminae (∼25°). Both were oriented orthogonally to the tonotopic axis. In contrast, cells in the pars ovoidea had their major axis of orientation parallel to the anteroposterior axis of the brain. Although a bitufted dendritic field was the norm, it was not uncommon for MGV neurons to have pronounced spatial asymmetries in their dendritic fields. A model is presented that incorporates cellular laminae and oriented dendritic growth to form frequency‐related slabs within the MGV. J. Comp. Neurol. 458:307–317, 2003. © 2003 Wiley‐Liss, Inc.
Normal chiasmatic routing of uncrossed projections from the ventrotemporal retina in albino Xenopus frogs
Authors: Grant Simon , Waller William , Bhalla Ashish , Kennard Christopher 
Published: March 2003

AbstractAlbino mammals lacking melanin in the embryonic retinal pigment epithelium (RPE) have abnormal retinal decussation patterns at the optic chiasm: their uncrossed projections are smaller and arise from fewer, more peripheral temporal retinal ganglion cells than in con‐specific wild‐types. To determine whether these abnormalities generalize to nonmammalian mutants, we used anterograde and retrograde labeling methods to compare the distribution of retinal projections to the thalamus in adult normal and albino Xenopus frogs. In both pigmentation phenotypes, crossed retinal terminations covered ∼80% of the neuropil of Bellonci (nB) and corpus geniculatum thalamicum (cgt) and uncrossed inputs occupied, respectively, approximately 75% and 25% of these two main visual centers. In the wild‐type frogs and in the albinos, ganglion cells giving rise to the crossed projections were distributed throughout the retina, whereas ipsilaterally projecting cells were confined to a specific ventrotemporal retinal division. This region comprised ∼40% of the total retinal area, was bordered by a well‐defined line of decussation, and contained an average of ∼3,000 ipsilaterally projecting ganglion cells of equivalent soma sizes in the two pigmentation phenotypes. In summary, we found no evidence of chiasmatic misrouting in the uncrossed retinothalamic projections of albino Xenopus, even though these pathways are substantial in normal frogs and share features in common with mammalian retinogeniculate projections. Our findings suggest that congenital RPE melanin deficiency results in major defects in the development of the retina and its central projections only in mammals. J. Comp. Neurol. 458:425–439, 2003. © 2003 Wiley‐Liss, Inc.
External inputs, stable equilibria and complete stability of CNNs
Authors: Li Xue Mei , Huang Li Hong , Wu Jianhong 
Published: March 2003

AbstractWe construct two cellular neural networks (CNNs) of three cells to show that a CNN can have stable equilibria, but is not completely stable and that the complete stability of CNN depends on the choice of external inputs. These phenomena cannot occur for two‐cell CNNs. Copyright © 2003 John Wiley & Sons, Ltd.
Fine‐needle aspiration of leiomyosarcoma: A correlative cytohistopathological study of 96 tumors in 68 patients
Authors: Klijanienko Jerzy , Caillaud Jean‐Michel , Lagacé Réal , Vielh Philippe 
Published: March 2003

AbstractTo better define the cytological features of various leiomyosarcoma (LMS) variants, we reviewed the fine‐needle aspiration material and the corresponding histologic sections of 96 tumors in 68 patients. Histological variants of LMS were as follows: 80 (83.3%) were of the classical/usual, seven (7.3%) were epithelioid, and nine (9.4%) were myxoid. Review of original cytology reports showed that 23 (24%) tumors were diagnosed as LMS and 69 (71.8%) as other types of malignancies. Two (2.1%) cases were reported as suspicious and two (2.1%) were unsatisfactory. The classical variants of LMS were characterized cytologically by various proportions of spindle‐shaped, cohesive, small‐ or large‐sized cells arranged in parallel alignment. Large spindle, round, binucleated, giant cells with intracytoplasmic granulations were frequently seen. Blunt‐ended nuclei, intranuclear inclusions and mitotic figures were occasionally seen, as well as stromal fragments. The epithelioid tumors were composed of an admixture of small and large, spindle‐shaped and round cells, also arranged in parallel alignment. Tumor cells with granular cytoplasm, blunt‐ended nuclei, intranuclear inclusions, mitotic figures, fibrous or myxoid stroma were not observed. The myxoid tumors disclosed large amounts of background myxoid matrix containing large spindle‐shaped and giant cells. Entities such as leiomyoma, malignant peripheral nerve sheath tumor, monophasic synovial sarcoma, and malignant fibrous histiocytoma should be considered in the differential diagnosis of LMS of the classical type. Epithelioid leiomyoma may share similar cytological features with epithelioid LMS. The cytological features of the myxoid variant of LMS can be easily confused with other types of benign and malignant mesenchymal tumors depicting degenerative myxoid changes and/or a myxoid matrix component. Diagn. Cytopathol. 2003;28:119–125. © 2003 Wiley‐Liss, Inc.
Marginal zone and mantle cell lymphomas: Assessment of cytomorphology in subtyping small B‐cell lymphomas
Authors: Murphy Bettina A. , Meda Brenton A. , Buss David H. , Geisinger Kim R. 
Published: March 2003

AbstractThe diagnosis of malignant lymphomas by fine‐needle aspiration biopsy (FNAB) is increasing in utilization. The cytomorphologic distinction among the small B‐cell lymphomas may be quite difficult. We are unaware of anyone who has compared directly mantle cell lymphoma (MCL) and marginal zone lymphoma (MZL) in FNAB. Our major goal was to examine the cytomorphologic attributes of MCL and MZL and to look for features distinctive of or suggestive of either neoplasm. Seven immunophenotypic MCL and seven immunophenotypic MZL aspirates were evaluated for a number of cytomorphologic features in direct smears. Features favoring MCL include a relatively monomorphic cellular population, prominent nuclear membrane contour irregularities, and mitotic figures. Conversely, a polymorphic cellular population suggested MZL. However, due to extensive overlap of specific cytologic features, the two lymphomas cannot be definitively distinguished based solely on cytomorphology. Although there are cytomorphologic attributes suggestive of either MCL or MZL, considerable overlap exists. Based on an individual case basis, the distinction cannot be made reliably by morphology alone; ancillary studies, e.g., immunophenotyping, are essential. Diagn. Cytopathol. 2003;28:126–130. © 2003 Wiley‐Liss, Inc.
Fine‐needle aspiration cytology and immunocytochemistry in the diagnosis of 24 gastrointestinal stromal tumors: A quick, reliable diagnostic method
Authors: Lozano Maria D. , Rodriguez J. , Algarra Salvador Martín , Panizo Angel , Sola Jesús J. , Pardo Javier 
Published: March 2003

AbstractThe diagnosis of gastrointestinal stromal tumors (GISTs) is generally established on histopathologic examination of surgical specimens. Fine‐needle aspiration (FNA), performed under the guidance of ultrasound or computed tomography, is being used with increasing frequency in an attempt to diagnose primary and/or metastatic GISTs before surgery. The present study was undertaken to characterize the cytological appearance of these tumors and to assess the role of cytology, together with immunocytochemistry (ICC), in the diagnosis of GISTs. Twenty‐four GISTs diagnosed by FNA cytology at our institution have been reviewed. Immunocytochemical studies with c‐kit and CD34 were performed in all cases on current or archival Papanicolaou‐stained smears. All cases stained with c‐kit, and 19 reacted with CD34. Cytomorphology and immunocytochemical characteristics are discussed. Our results confirm the utility of FNA together with ICC in the diagnosis of primary and/or metastatic GISTs. Diagn. Cytopathol. 2003;28:131–135. © 2003 Wiley‐Liss, Inc.
Nitric oxide release, EDHF, and the role of potassium channels in coronary circulation
Authors: He Guo‐Wei 
Published: March 2003

AbstractThe endothelium relaxes vascular smooth muscle cells through at least three factors: nitric oxide (NO), prostacyclin (PGI2), and endothelium‐derived hyperpolarizing factor (EDHF). In the coronary circulation, we have conducted a series of experiments to study: 1) the inhibitory effects of NOS on the production of NO under stimulated status; 2) whether EDHF plays a role in either large or microarteries; 3) the cellular membrane potential hyperpolarization linked with relaxation; 4) the potassium channels involved in EDHF‐mediated relaxation and hyperpolarization; and 5) EDHF‐function related to open‐heart surgery. In porcine coronary arteries, NO release was directly measured by electrochemical methods using an NO‐specific electrode and an NO meter. The cellular membrane potential of smooth muscle cells was measured electrophysiologically by using a microelectrode in both large and small coronary arteries. Isometric force recording was used to study relaxations in organ chambers for large arteries and in myograph for microarteries. This article reviews these aspects. A) In large arteries pretreated with indomethacin, bradykinin (BK) evoked a rise in [NO] from 5.5±2.4 nM to 105.0±19.6 nM and hyperpolarization. L‐NNA treatment significantly reduced the BK‐stimulated rise in [NO] to 32.1±11.3 nM but did not affect hyperpolarization. B) Oxyhemoglobin eliminated indomethacin and L‐NNA‐resistant rise in [NO] but not relaxation (42.3±4.4%) and repolarization (−40±2 mV) by BK. C) Tetraethylammonium, charybdotoxin, iberiotoxin, and apamin, used alone or in combination, partially decreased the BK‐induced responses. D) EDHF‐mediated relaxation and hyperpolarization are reduced by exposure to hyperkalemic cardioplegia. We conclude: i) that in porcine coronary large and microarteries, both EDHF and NO play important role in the endothelium‐dependent relaxation; ii) that NOS inhibitors reduce but do not completely eliminate NO production; iii) that Ca2+‐activated K+ channels (BKCa and SKCa) play an important role in mediating the BK‐induced responses; and iv) that EDHF‐function can be protected by pharmacological methods. Drug. Dev. Res. 58:23–27, 2003. © 2003 Wiley‐Liss, Inc.
Serotonin receptor as a potential therapeutic target for pulmonary vascular remodeling
Authors: Wang Huailiang 
Published: March 2003

AbstractPulmonary hypertension can be caused in most mammalian species by numerous serotonergic drugs. That the 5‐HT1B/1D‐receptor agonist sumatriptan demonstrated a potent vasopressor response in the pulmonary circulation in human subjects suggests that the 5‐HT1B/1D receptor may be involved in the vasoconstriction of human pulmonary arteries. Both 5‐HT1B‐ and 5‐HT1D‐receptor mRNA exist in the trigeminal ganglion. Only 5‐HT1B receptor mRNA expression was detected in pulmonary artery smooth muscle. A higher level of 5‐HT1B receptor mRNA expression existed in the pulmonary artery from the monocrotaline‐induced chronic pulmonary hypertensive rat, which was found to be associated with a higher vasoconstrictor effect to 5‐HT. The 5‐HT1B receptor mediates pulmonary vasoconstriction and the enhanced expression of 5‐HT1B receptor mRNA is closely related to the augmentation of 5‐HT‐induced pulmonary vasoconstriction. Therefore, serotonin may be a mediator of pulmonary hypertension via 5‐HT1B receptor‐induced pulmonary vasoconstriction. The enhanced expression of 5‐HT1B receptor mRNA is closely related to the augmentation of 5‐HT‐induced pulmonary vasoconstriction, suggesting that the 5‐HT1B receptor is one of the important mechanisms of pulmonary hypertension; this may provide a novel and potential therapeutic target for this disease. Drug Dev. Res. 58:69–73, 2003. © 2003 Wiley‐Liss, Inc.
Transmural dispersion of action potential duration and heterogeneous changes in L‐type calcium current in rabbit heart three months after myocardial infarction
Authors: Ma Jie , Li Yang , Zhang Cun‐Tai , Xiao Jian‐Ming , Lu Zai‐Ying 
Published: March 2003

AbstractThe transmural dispersion of APD (TD‐APD) and heterogeneous changes in L‐type calcium current (ICa.L) in rabbit hearts were examined 3 months after myocardial infarction. Compared to the control group, APDs of cells from the epimyocyte, midmyocyte, and endomyocyte layers remote from the infarct site were all lengthened: TD‐APD was increased (288.32±19.56 ms vs. 210.32±17.43 ms in the control group; P<0.05). No significant differences in APD or TD‐APD were observed between the sham‐operated and control groups (P>0.05). Compared to the control group, ICa.L density was decreased in the infarct group, the reduction being most prominent in cells from the endomyocyte layer (from 16.12±1.60 pA·pF‐1 to 8.73±0.06 pA·pF‐1, decreased 45.82%), with reductions in cells from the midmyocyte and epimyocyte layers of 39.72% and 37.01%, respectively. There was no significant difference in ICa.L density between the sham‐operated and control groups (P>0.05). Drug Dev. Res. 58:122–124, 2003. © 2003 Wiley‐Liss, Inc.
Effects of endothelin‐1 mRNA antisense oligodeoxynucleotides on ischemic arrhythmias in isolated rat hearts
Authors: Yuan Wen‐Jun , Qiu Jing‐Wei , Lin Li , Pan Xiu‐Jie , Ren An‐Jing , Chen Hong , Tang Chao‐Shu 
Published: March 2003

AbstractThe role of endothelin‐1 (ET‐1) in acute ischemic arrhythmia is controversial. To illustrate the involvement of cardiac ET‐1 in ischemic arrhythmia, the effects of ET‐1 mRNA antisense oligodeoxy‐nucleotides (AS‐ODNs) on acute ischemic arrhythmia were observed. ET‐1 AS‐ODN was injected i.v. in rats 2 h before the experimental procedure and the ischemic arrhythmia caused by occlusion of the left anterior descending (LAD) coronary artery was observed in the isolated perfused heart. The results show that: 1) In normal perfused rat hearts, a small number of ventricular ectopic beats (VEBs) were observed and neither ventricular tachycardia (VT) nor heart arrest occurred. 2) LAD occlusion elicited various ischemic arrhythmias in isolated hearts. No differences in the incidences or numbers of the arrhythmias were found between isolated hearts which had received normal saline (NS) and those which had received ET‐1 ODNs (sense‐ODN and scrambled‐ODN) in vivo. VT occurred in all hearts and the percentage of heart arrest was 33.3% in the NS group, 12.5% in the sense‐ODN group, and 25% in the scrambled ODN group. 3) ET‐1 AS‐ODN dose‐dependently decreased the incidence of VT, the arrhythmia score, the numbers of single VEBs and VT, and no heart arrest was observed in the hearts pretreated with ET‐1 AS‐ODN. These results demonstrated a contributory role for endogenous ET‐1 in the genesis of ischemic arrhythmia in this rat heart model of arrhythmia. Drug Dev. Res. 58:138–144, 2003. © 2003 Wiley‐Liss, Inc.
Influence of parental deprivation on the behavioral development in Octodon degus: Modulation by maternal vocalizations
Authors: Braun Katharina , Kremz Petra , Wetzel Wolfram , Wagner Thomas , Poeggel Gerd 
Published: March 2003

AbstractRepeated separation from the family during very early stages of life is a stressful emotional experience which induces a variety of neuronal and synaptic changes in limbic cortical areas that may be related to behavioral alterations. First, we investigated whether repeated parental separation and handling, without separation from the family, leads to altered spontaneous exploratory behavior in a novel environment (open field test) in 8‐day‐old Octodon degus. Second, we tested whether the parentally deprived and handled animals display different stimulus‐evoked exploratory behaviors in a modified open field version, in which a positive emotional stimulus, the maternal call, was presented. In the open field test a significant influence of previous emotional experience was found for the parameters of running, rearing, and vocalization. Parentally deprived degus displayed increased horizontal (running) and vertical (rearing) motoric activities, but decreased vocalization, compared to normal and handled controls. The presentation of maternal vocalizations significantly modified running, vocalization, and grooming activities, which in the case of running activity was dependent on previous emotional experience. Both deprivation‐induced locomotor hyperactivity together with the reduced behavioral response towards a familiar acoustic emotional signal are similar to behavioral disturbances observed in human attachment disorders. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 237–245, 2003.
Latent inhibition of conditioned odor potentiation of startle: A developmental analysis
Authors: Richardson Rick , Fan Michelle , Parnas A. Sophie 
Published: March 2003

AbstractWe conducted a two‐part study of age and latent inhibition in the rat. In the first part of the study, rats given odor–shock pairings at 23 or 75 days of age exhibited a potentiated startle response in the presence of the odor the following day. This effect did not occur in rats trained at 16 or 20 days of age. Odor pre‐exposure on the day prior to conditioning markedly reduced the odor potentiation of startle effect in 23‐ and 75‐day‐old rats but had no effect in 16 and 20‐day‐olds. In the second part of the study, rats were pre‐exposed to the odor at 16 or 20 days of age and then conditioned at 23 days of age. When tested the day after conditioning, these pre‐exposed rats exhibited a disruption in the odor potentiation of startle effect. We compare our results with other studies of latent inhibition, and with recent studies on whether conditioned responses are appropriate to the animal's age at training or their age at test. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 261–268, 2003.
Reinstatement maintains a memory in human infants for 1½ years
Authors: Hartshorn Kristin 
Published: March 2003

AbstractThis study tested the proposition of Campbell and Jaynes (1966) that reinstatement is the mechanism by which early memories are maintained over a significant period of development. In four progressive replications, 6‐month‐old human infants learned to move a miniature train around a track by lever‐pressing. They received a brief reinstatement at 7, 8, 9, 12, and 18 months of age and a final retention test at 2 years of age. Although 6‐month‐olds usually remember this task for only 2 weeks, after five reinstatements they exhibited significant retention 1½ years later. Untrained yoked controls that received the same reinstatement regimen exhibited no retention after any delay. These findings reveal that the immaturity of the brain at the time of encoding is not the rate‐limiting step in whether infants remember over the long term. Rather, as long as infants periodically encounter a nonverbal reminder, they can maintain early memories over a significant period of development. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 269–282, 2003.
Dynamic spatiotemporal expression of LIM genes and cofactors in the embryonic and postnatal cerebral cortex
Authors: Bulchand Sarada , Subramanian Lakshmi , Tole Shubha 
Published: March 2003

AbstractLIM‐Homeodomain (LIM‐HD) genes encode a family of transcription factors known to be involved in development and patterning in several systems. Previously, we have shown that LIM‐HD gene Lhx2 is required for the formation of a crucial boundary in the dorsal telencephalon (Bulchand et al. [2001] Mech Dev 100:165–175). To further explore the role of LIM‐HD genes as well as the broader LIM gene family in dorsal telencephalic development, we examined the expression pattern of the members of this gene family and their cofactors in the developing mouse cerebral cortex. Transcription factor activity of the LIM‐HD proteins requires the formation of a tetrameric complex consisting of two LIM‐HD molecules linked by a dimer of cofactor (Clim) molecules. LIM‐only (Lmo) proteins can interfere with this process by competing for the cofactors. LIM‐HD protein function, thus, can be modulated by the presence of the appropriate Clim or Lmo molecules. At least 13 LIM‐HD, 4 Lmo, and 2 Clim genes have been identified in the mouse. Several of these genes exhibit complex spatiotemporal patterns spanning different stages of cortical development, from embryonic to postnatal ages. Noteworthy features of the expression patterns include delineation of boundaries within the developing cortex, up‐ or down‐regulation during formation of selected cortical layers, and a striking complementarity of expression of several members consistent with specific functions in cortical development. Significantly, in some cases, Lmo or Clim gene expression is robust where no LIM‐HD gene expression is detectable. These results suggest multiple and distinct roles for LIM‐HD, Lmo, and Clim genes in cortical development, and also support a LIM‐HD–independent role for some Lmo and Clim members. Development Dynamics, 2003. © 2003 Wiley‐Liss, Inc.