bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunocytochemical detection of calcitonin gene‐related peptide in the postnatal developing rat cochlea
Authors: Merchan‐Perez Angel , Gil‐Loyzaga Pablo , Eybalin Michel 
Published: April 2003

AbstractUsing the immunofluorescence technique, three populations of fibers staining for calcitonin gene‐related peptide are identified in postnatal developing cochleas and in adult rat cochleas. During the maturation of the cochlea, the immunostaining first appears in the basal turn and then extends toward the apex of the cochlea. The first population of immunostained fibers belongs to the lateral olivocochlear innervation. It is observed at postnatal day 4 within the inner spiral bundle of the organ of Corti. The second population of calcitonin gene‐related peptide‐like immunostained fibers belongs to the medial olivocochlear innervation. It is first identified at postnatal day 6 under the outer hair cells, generally in the first row. In the older stages, this population of fibers progressively extends toward the external row of outer hair cells. Finally, the third population of immunostained fibers belongs to the sympathetic supply of the cochlea. They can be identified at postnatal day 6 around the cochlear artery and its branches, and also within the entire modiolus.Our results confirm the presence of calcitonin gene‐related peptide in fibers of the lateral and medial efferent innervations of the cochlea. They indicate an early appearance of calcitonin gene‐related peptide in the developing cochlea, before the onset of the cochlear function, suggesting for this peptide either a neurotrophic function or a regulation of the early cochlear potentials at the level of the lateral efferent synapses.
Sex‐specific schedule in steroid response of rhombencephalic catecholaminergic neurons in vitro
Authors: Küppers Eva , Pilgrim Christoph , Reisert Ingrid 
Published: April 2003

AbstractMorphological differentiation of tyrosine hydroxylase‐immunoreactive neurons was investigated in dissociated cell cultures of rhombencephalon of male and female day 14 rat embryos grown in the presence or absence of sex steroids. Numbers of cells were counted and morphometrical measurements carried out of soma size and length of tyrosine hydroxylase‐immunoreactive neurites (processes). Subtle sex differences in length of stained neurites, which were not yet present after 3 days in vitro, were observed after 6 days in cultures grown in the absence of sex steroids. Female tyrosine hydroxylase‐immunoreactive neurites could be traced over longer distances than male ones. Daily treatment of cultures with testosterone or 17β‐estradiol resulted in an increase of lengths of stained neurites of female neurons after 3 days and of male neurons after 6 days in vitro. Regarding cell numbers or soma size, there were no differences between genders or between controls and hormone‐treated cultures.It is concluded that sex steroids promote the outgrowth of neurites from noradrenergic neurons within a gender‐specific time frame. It appears that the critical period for developmental effects of sex steroids differs between males and females.
Quantitative autoradiographic study of the postnatal development of benzodiazepine binding sites and their coupling to GABA receptors in the rat brain
Authors: Daval Jean‐Luc , Werck Marie‐Christine , Nehlig Astrid , de Vasconcelos Anne Pereira 
Published: April 2003

AbstractThe postnatal development of benzodiazepine binding sites in the rat brain was studied by quantitative receptor autoradiography using [3H]flunitrazepam. The coupling of these sites to GABA receptors was assessed in 43 cerebral structures by examining the effects of in vitro addition of GABA on flunitrazepam specific binding. Benzodiazepine‐specific binding was relatively high at birth and exhibited an heterogeneous distribution pattern, anatomically different from the adult one. Data showed a sequential development of benzodiazepine receptors in relation to the time course of maturation of cerebral structures. A proliferation peak which paralleled rapid brain growth was noticed. High levels of benzodiazepine sites were transiently observed in some areas, e.g. thalamus and hypothalamus, and might be related to maturational events. In every brain structure examined, benzodiazepine binding sites were linked to GABA receptors. However, enhancement of flunitrazepam specific binding by exogenous GABA differed according to the structures studied and decreased during development, suggesting some changes in the control of GABA/benzodiazepine regulation during postnatal maturation.
Postnatal development of descending motor pathways studied in man by percutaneous stimulation of the motor cortex and the spinal cord
Authors: Khater‐Boidin Josette , Duron Bernard 
Published: April 2003

AbstractUsing the percutaneous electrical stimulation of the brain and spinal cord, we have determined central motor pathway conduction velocities in a group of 19 healthy fullterm newborns (average post‐conceptional age 39.8 weeks) and in 19 infants between 2 months and 8 years of age. The newborns were examined during the first postnatal week. The percutaneous stimulation of the motor cortex and of the cervical and lumbar enlargements of the spinal cord was made by means of bipolar electrodes. The evoked compound muscle action potentials were recorded by bipolar surface electrodes fixed on the skin overlying the thenar eminence muscles and the tibialis anterior muscle.In fullterm newborns, the responses of lower limb muscles to cortical stimulation were more difficult to obtain than those of upper limb muscles. Conduction velocities of central motor fibres along the spinal cord (between vertebrae C7 and L4) were around 10 m/sec in fullterm newborns and 38 m/sec at the age of 4 years. These values are considerably lower than those described for adult man (48–60 m/sec). The adult values are established around the age of 8 years.
Growth of ascending spinal axons in CNS scar tissue
Authors: Frisén Jonas , Fried Kaj , Sjögren Ann Margret , Risling Mårten 
Published: April 2003

AbstractThe aim of the present study was to test the capacity of spinal cord scar tissue to assist and sustain axon regrowth. In adult rats and cats the dorsal funiculus (DF) was cut at mid‐thoracic or lumbar level and a superficial incision in the DF rostral to the lesion was made in order to extend the penetrating lesion. Axonal tracing in rats 50–100 days postinjury with anterogradely transported wheatgerm agglutinin‐conjugated horseradish peroxidase or rhodamine‐conjugated dextran demonstrated that nerve fibers had entered the scar tissue. Axon ingrowth in the scar was further indicated by axonal immunoreactivity to the growth‐associated protein GAP‐43. The scar tissue showed low‐affinity neurotrophin receptor‐like immunoreactivity in association with blood vessels and in the interstitium. The integrity of the blood‐brain barrier in the extended dorsal funiculus lesion was disrupted for at least 11 months postinjury, assessed by i.v. injections of free HRP or Evans blue. The present study shows that penetrating injury in the dorsal funiculus produces a CNS environment permissive for axonal sprouting and that PNS influence is not necessary for spinal tract regrowth. A possible relationship between the absence of an intact BBB and injury‐induced axonal sprouting is discussed.
Migration and differentiation of PC12 cells transplanted into the rat spinal cord
Authors: Zompa E.A. , Pizzo D.P. , Hulsebosch C.E. 
Published: April 2003

AbstractTo test the hypothesis that transplanted neuronal or neuronal‐like cell lines, grown in vitro, might survive and differentiate in the mammalian spinal grey matter, adult male Sprague‐Dawley rats (N=5) were injected with a suspension of between 3 × 105 and 1.0 × 106 DiI labeled, undifferentiated rat pheochromocytoma (PC12) cells in sterile phosphate buffered saline. The PC12 cell line was chosen since, in certain in vitro conditions, this cell line serves as a model of neuronal differentiation, which includes the ability to conduct action potentials and form functional synapses. After a survival time of 7 or 8 days, the spinal cords were removed, cryosectioned longitudinally and examined for detection of DiI labeled PC12 cells using fluorescent microscopy. The number of DiI labeled profiles and the proportions of the DiI cells which were differentiated were counted per section in at least five non‐contiguous sections per animal. Differentiation was defined as cells with neurite‐like extensions which exceeded twice the soma diameter. Results demonstrated the following: (1) from 2 to 15% of the transplanted PC12 cells survived (2) migration within the spinal grey matter occurred since PC12 cells were found as much as 510 μm away from the injection site (3) of the surviving PC12 cell population, a proportion of between 60 and 80% were differentiated, many with two or more neurite‐like processes, in all of the rats (4) no mitotic profiles were observed in DiI labelled cells (5) undifferentiated PC12 cells were juxtaposed to the lumens of small blood vessels or within the lesion cavity. Although the specific factors remain to be elucidated, the observed PC12 migration and differentiation within the host spinal grey matter appears to be controlled by factors in the microenvironment. These data support the use of a homogeneous in vitro population of neuronal or neuronal‐like cells, which are readily accessible to transfection with the appropriate genes, as transplant sources for the injured spinal cord.
Structural maturation, cell proliferation and bioelectric activity in long‐term slice‐cultures of immature rat hippocampus
Authors: Hajós Ferenc , Balázs Robert , Baker Robert E. , Gerics Balázs , Nuijtinck Roger 
Published: April 2003

AbstractExplants of transverse slices of the 6‐day‐old rat hippocampus were grown in a serum‐free medium for 2–14 days. Histology performed after various culturing periods demonstrated that these slices maintain a high degree of 3‐dimensional organotypy, while undergoing growth and differentiation of the main cellular elements similar to that seen in vivo. Histological indications of continuing cell proliferation were verified by autoradiography showing a labelling of neuroblasts in the dentate gyrus and of glioblasts at the sites of gliogenesis observed in vivo. Spontaneous bioelectric activity and evoked potentials were recorded, both indicating the development of impulse generation and neuronal connectivity within the explant. Silver impregnation and electron microscopic studies lent further support for the presence of neuronal networks intrinsic to the hippocampus. These findings suggest that within the period studied the hippocampal slice cultures mature in a fashion similar to that seen in situ.
Stimulatory effect of opioid peptides and naloxone on rat spinal cord cells in primary dissociated culture
Authors: Kozlova Marina , Kalentchuk Vyachieslav 
Published: April 2003

AbstractOpioid peptides leu‐enkephalin, a synthetic analog of enkephalin dalargin and an opiate receptor blocker naloxone were studied for their morphological effect on the cells of dissociated cultures of rat spinal cord.Low density seeding of cells (3.105; 6.105 cells/ml) on collagen substrate was performed to document that opioid peptides increase the number of cultured cells and neurite outgrowth and lead to the activation of the initiated processes of aggregate formation. Upon higher density of plating (5.106 cells/ml) with poly‐l‐lysine as a substrate, activation of the aggregate formation process was demonstrated, both opioid peptides and naloxone leading to an increase in the size of aggregates. Statistical treatment of the results obtained in this set of experiments documented that leu‐enkephalin, dalargin and naloxone increased 2.2‐, 2.2–2.6‐, 2.4‐fold, respectively, the size of aggregates compared to the control, i.e. the reaction of spinal cord cells to opioid peptides and opiate receptor blocker naloxon was unidirected. The total effect of opioid peptides and naloxon resulted in a 3.6‐fold increase in the size of the aggregates compared to the control. The data obtained in this study allow the assumption that opioid peptides and naloxone, while activating spinal cord cells via receptors of a different type, manifest the properties of factors thus increasing survival and adhesion of spinal cord cells in culture.
Linking performance drivers in production planning and inventory control to process choice
Authors: Safizadeh M.Hossein , Ritzman Larry P. 
Published: April 2003

AbstractThis study investigates how process choice relates to production planning and inventory control decisions. We empirically examine the validity of deductively derived patterns about these types of decisions. More importantly, we look for normative insights by exploring how production planning and inventory control decisions affect operations performance. Our findings show that production line and continuous flow plants use more of a level production strategy, and carry less raw material and work‐in‐process inventory. The performance drivers for these plants, through which the operations function excels, are effective utilization of equipment, reduced finished goods inventory, and reduced setup down time. To gain forward demand visibility and batching economies, job and batch shops rely much more on backlogs in their planning process. These plants use more of a production chase strategy and position inventory lower in the bills of materials. Four performance drivers for top‐performing job and batch shops are to find ways that better anticipate customers' orders, have a more responsive chase strategy, carry less raw material or purchased inventory, and shorten production planning horizon, partly through less reliance on backlogs. It is intriguing that top‐performing plants not only do the expected things, given their choice of process, but also excel in selected dimensions—some of which fit the profile normally associated with a different process choice. To monitor and continuously improve operations, evaluation ‘scorecards’ should pay particular attention to performance drivers, which change depending on the plant's process choice.
Platelet counts in depressed patients treated with amitriptyline or paroxetine
Authors: Lederbogen F. , Hörer E. , Hellweg R. , Heuser I. , Deuschle M. 
Published: April 2003

AbstractObjectiveTo assess whether therapy with two widely used antidepressants influences platelet counts.Subjects and methodsIn 90 patients hospitalized for treatment of a major depressive episode according to DSM-IV, platelet counts were performed after a 6 d antidepressant-free run-in period and again after 35 d of active standardized treatment with amitriptyline (n = 40) or paroxetine (n = 50).ResultsThere was a trend for platelet counts to increase during treatment with amitriptyline (from 245.5 ± 68.6 to 256.8 ± 69 cells × 109 L-1, P < 0.06); no change was observed during treatment with paroxetine (from 232.6 ± 58.3 to 234.6 ± 68.9 cells × 109 L-1, n.s).ConclusionsTreatment with amitriptyline tends to be associated with elevated platelet counts. The cause for this increase is not known, but may be relevant in terms of patients’ long-term thromboembolic risk.
Backbone 15N relaxation analysis of the N‐terminal domain of the HTLV‐I capsid protein and comparison with the capsid protein of HIV‐1
Authors: Cornilescu Claudia C. , Bouamr Fadila , Carter Carol , Tjandra Nico 
Published: April 2003

AbstractHuman T‐cell leukemia virus type 1 (HTLV‐I) is an oncogenic retrovirus that exhibits specific tropism for human T‐cells. The capsid (CA) proteins of retroviruses share highly conserved secondary and tertiary structures. However, they can form quaternary structures (assembled cores) that are conical (e.g., the lentivirus subgroup, including HIV) or spherical (e.g., the oncovirus subgroup, including HTLV). The intrinsic features that drive these differences are not understood. So far, only structural studies have been used as a basis for comparison. Dynamics may play a role in particle formation. High‐resolution nuclear magnetic resonance (NMR) 15N relaxation data (T1, T1ρ, and NOE) have been used to characterize the backbone dynamics of the N‐terminal domain (NTD) of the oncovirus HTLV‐I and to compare with the CA NTD of HIV‐1. Large variations in the 15N heteronuclear NOEs and transversal relaxation rates for individual residues are consistent with the bundle RMSD of the previously calculated NMR structures. The β‐hairpin and CyP‐A loop exhibit different mobility in HTLV‐I and HIV‐1. The overall hydrodynamic property of the HTLV‐I capsid NTD is quite distinct from the HIV‐1.
Stability of monomeric Cro variants: Isoenergetic transformation of a type I′ to a type II′ β‐hairpin by single amino acid replacements
Authors: Mollah A.K.M.M. , Stennis Rhonda L. , Mossing Michael C. 
Published: April 2003

AbstractThe thermodynamic stabilities of three monomeric variants of the bacteriophage λ Cro repressor that differ only in the sequence of two amino acids at the apex of an engineered β‐hairpin have been determined. The sequences of the turns are EVK‐XX‐EVK, where the two central residues are DG, GG, and GT, respectively. Standard‐state unfolding free energies, determined from circular dichroism measurements as a function of urea concentration, range from 2.4 to 2.7 kcal/mole, while those determined from guanidine hydrochloride range from 2.8 to 3.3 kcal/mole for the three proteins. Thermal denaturation yields van't Hoff unfolding enthalpies of 36 to 40 kcal /mole at midpoint temperatures in the range of 53 to 58°C. Extrapolation of the thermal denaturation free energies with heat capacities of 400 to 600 cal/mole deg gives good agreement with the parameters determined in denaturant titrations. As predicted from statistical surveys of amino acid replacements in β‐hairpins, energetic barriers to transformation from a type I′ turn (DG) to a type II′ turn (GT) can be quite small.
A novel member of the split βαβ fold: Solution structure of the hypothetical protein YML108W from Saccharomyces cerevisiae
Authors: Pineda‐Lucena Antonio , Liao Jack C.C. , Cort John R. , Yee Adelinda , Kennedy Michael A. , Edwards Aled. M. , Arrowsmith Cheryl H. 
Published: April 2003

AbstractAs part of the Northeast Structural Genomics Consortium pilot project focused on small eukaryotic proteins and protein domains, we have determined the NMR structure of the protein encoded by ORF YML108W from Saccharomyces cerevisiae. YML108W belongs to one of the numerous structural proteomics targets whose biological function is unknown. Moreover, this protein does not have sequence similarity to any other protein. The NMR structure of YML108W consists of a four‐stranded β‐sheet with strand order 2143 and two α‐helices, with an overall topology of ββαββα. Strand β1 runs parallel to β4, and β2:β1 and β4:β3 pairs are arranged in an antiparallel fashion. Although this fold belongs to the split βαβ family, it appears to be unique among this family; it is a novel arrangement of secondary structure, thereby expanding the universe of protein folds.
Mutations in domain a′ of protein disulfide isomerase affect the folding pathway of bovine pancreatic ribonuclease A
Authors: Ruoppolo Margherita , Orrù Stefania , Talamo Fabio , Ljung Johanna , Pirneskoski Annamari , Kivirikko Kari I. , Marino Gennaro , Koivunen Peppi 
Published: April 2003

AbstractProtein disulfide isomerase (PDI, EC 5.3.4.1), an enzyme and chaperone, catalyses disulfide bond formation and rearrangements in protein folding. It is also a subunit in two proteins, the enzyme collagen prolyl 4‐hydroxylase and the microsomal triglyceride transfer protein. It consists of two catalytically active domains, a and a′, and two inactive ones, b and b′, all four domains having the thioredoxin fold. Domain b′ contains the primary peptide binding site, but a′ is also critical for several of the major PDI functions. Mass spectrometry was used here to follow the folding pathway of bovine pancreatic ribonuclease A (RNase A) in the presence of three PDI mutants, F449R, Δ455–457, and abb′, and the individual domains a and a′. The first two mutants contained alterations in the last α helix of domain a′, while the third lacked the entire domain a′. All mutants produced genuine, correctly folded RNase A, but the appearance rate of 50% of the product, as compared to wild‐type PDI, was reduced 2.5‐fold in the case of PDI Δ455–457, 7.5‐fold to eightfold in the cases of PDI F449R and PDI abb′, and over 15‐fold in the cases of the individual domains a and a′. In addition, PDI F449R and PDI abb′ affected the distribution of folding intermediates. Domains a and a′ catalyzed the early steps in the folding but no disulfide rearrangements, and therefore the rate observed in the presence of these individual domains was similar to that of the spontaneous process.
Thyroid Hormone Receptor-Specific Interactions with Steroid Receptor Coactivator-1 in the Pituitary
Authors: Sadow Peter M. , Koo Eugene , Chassande Olivier , Gauthier Karine , Samarut Jacques , Xu Jianming , O’Malley Bert W. , Seo Hisao , Murata Yoshiharu , Weiss Roy E. 
Published: April 2003

Abstract
Steroid receptor coactivator-1 (SRC-1) is a transcription cofactor that enhances the hormone-dependent action mediated by the thyroid hormone (TH) receptor (TR) as well as other nuclear receptors. However, it is not known whether the SRC-1-mediated activation of TH-regulated gene transcription is TR isoform specific in the pituitary. We generated mice that were deficient in TRα and SRC-1 (TRα0/0SRC-1−/−), as well in TRβ and SRC-1 (TRβ−/−SRC-1−/−), and thyroid function tests and effects of TH deprivation and TH treatment were compared with wild-type mice or mice with deletion of either TRs or SRC-1 alone. We have shown that 1) TRβ−/−SRC-1−/− mice demonstrate more severe TH resistance than either the SRC-1−/− or TRβ−/− mice; the additive effect indicates that SRC-1 has an independent role in TH action over that of TRβ; 2) SRC-1 facilitates TRβ and TRα-mediated down-regulation of TSH, as TRα0/0SRC-1−/− mice demonstrate TH resistance rather than hypersensitivity as seen in TRα0/0mice; and 3) a compensatory increase in SRC-1 expression is associated with the TH hypersensitivity seen in TRα-deficient animals. We conclude that SRC-1 action in the pituitary mediates TH action via specific TR subtypes.
Surface pressure disturbance in the Ebro Valley (Spain) produced by the Pyrenees mountains during PYREX
Authors: Argandoña J. D'IAZ DE , Ezcurra A. , Bénech B. 
Published: April 2003

AbstractIn this paper, the pressure anomaly created by the Pyrenees during the Pyrenees Experiment (PYREX) in the Ebro Valley is studied and analysed. In the first part, pressure disturbance is obtained during some selected cases of PYREX by subtracting the synoptic component from the pressure registered by microbarographs and regular meteorological stations located in the area. As expected from a linear model, a low pressure is found for northerly synoptic winds and a high pressure for southerly synoptic winds. Data shows that the maximum pressure anomaly observed may reach values of the order of 7 hPa. Pressure‐anomaly spatial patterns found inside the valley are classified by using principal component analysis (PCA). It is found that the first axes deduced from the PCA carried out represent 75% of the variance in pressure data, indicating that all the stations analysed observed pressure anomalies in a correlated manner. Pressure anomalies are then related to incident‐air characteristics expressed as Froude and Rossby numbers. Significant correlation is generally found with these numbers in all cases, demonstrating the dynamic origin of the pressure anomaly computed. Copyright © 2007 Royal Meteorological Society