bluuebunny/crossref_metadata_2025_split huggingface dataset:
Brain‐derived neurotrophic factor‐, neurotrophin‐3‐, and tyrosine kinase receptor‐like immunoreactivity in lingual taste bud fields of mature hamster after sensory denervation
Authors: Ganchrow Donald , Ganchrow Judith R. , Verdin‐Alcazar Mary , Whitehead Mark C. 
Published: October 2004

AbstractUnlike lingual taste buds in most mammals, fungiform buds on the anterior tongue of mature hamster survive sensory denervation. The role of the neurotrophin ligands, brain‐derived neurotrophic factor (BDNF) and neurotrophin‐3 (NT‐3), and their respective tyrosine kinase (Trk) receptors, TrkB and TrkC, in denervated taste buds is not known. The present report investigates changes in the degree of gemmal cell immunoreactivity (IR) (i.e., number of immunoreactive cells/bud profile) and density of nerve fiber‐IR of these markers in unilaterally denervated mature hamsters. The fungiform bud field after chorda tympani/lingual nerve resection is compared with the nerve‐dependent, posterior tongue foliate and circumvallate bud fields after glossopharyngeal nerve resection. Four weeks post lesion, the number of denervated fungiform buds matched that on the unoperated side, whereas denervated foliate and circumvallate bud counts decreased by 72% and 38%, respectively. In taste buds that survived on the posterior tongue, the degree of foliate bud cell BDNF‐, NT‐3‐, and TrkB‐like IR, and circumvallate bud cell BDNF‐ and NT‐3‐like IR, significantly decreased compared with the unoperated side. In contrast, for anterior tongue fungiform bud cells, the degree of neurotrophin‐ and receptor‐like IR was relatively less affected: NT‐3‐ and TrkB‐like IR were unchanged; BDNF‐like IR, although significantly decreased, was also maintained. Moreover, TrkB‐like fiber IR was essentially eliminated within and surrounding fungiform buds. Hence, NT‐3‐, BDNF‐, and TrkB‐like IR in fungiform gemmal cells may reflect an autocrine capacity promoting survival. Because TrkC‐like IR in bud cells is absent (i.e., immunonegative), and sparse in fibers intragemmally and perigemmally, NT‐3 may also bind to bud cell TrkB so as to sustain fungiform gemmal cell viability post denervation. J. Comp. Neurol. 455:25–39, 2003. © 2002 Wiley‐Liss, Inc.
On the evolution of sharp fronts for the quasi‐geostrophic equation
Authors: Rodrigo José Luis 
Published: October 2004

AbstractWe consider the problem of the evolution of sharp fronts for the surface quasi‐geostrophic (QG) equation. This problem is the analogue to the vortex patch problem for the two‐dimensional Euler equation.The special interest of the quasi‐geostrophic equation lies in its strong similarities with the three‐dimensional Euler equation, while being a two‐dimen‐sional model. In particular, an analogue of the problem considered here, the evolution of sharp fronts for QG, is the evolution of a vortex line for the three‐dimensional Euler equation. The rigorous derivation of an equation for the evolution of a vortex line is still an open problem. The influence of the singularity appearing in the velocity when using the Biot‐Savart law still needs to be understood.We present two derivations for the evolution of a periodic sharp front. The first one, heuristic, shows the presence of a logarithmic singularity in the velocity, while the second, making use of weak solutions, obtains a rigorous equation for the evolution explaining the influence of that term in the evolution of the curve.Finally, using a Nash‐Moser argument as the main tool, we obtain local existence and uniqueness of a solution for the derived equation in the C∞ case. © 2004 Wiley Periodicals, Inc.
Transport inequalities, gradient estimates, entropy and Ricci curvature
Authors: von Renesse Max‐K. , Sturm Karl‐Theodor 
Published: October 2004

AbstractWe present various characterizations of uniform lower bounds for the Ricci curvature of a smooth Riemannian manifold M in terms of convexity properties of the entropy (considered as a function on the space of probability measures on M) as well as in terms of transportation inequalities for volume measures, heat kernels, and Brownian motions and in terms of gradient estimates for the heat semigroup. © 2004 Wiley Periodicals, Inc.
Photochemistry of Molecules Relevant to the Atmosphere: Photodissociation of Nitric Acid in the Gas Phase
Authors: Huber J. Robert 
Published: October 2004

AbstractThis Minireview gives an account of the photochemical decay of nitric acid HNO3 in the gas phase, which has been well investigated under bulk and molecular‐beam conditions. Due to the importance of this molecule in atmospheric chemistry, attention was paid to the irradiation regions around 300 and 200 nm, where solar photolysis of HNO3 is expected to be particularly efficient. While the low‐energy region is characterized by the products OH and NO2, the high‐energy region gives rise to a variety of photochemical decay pathways, dominated by channels which lead to the products HONO+O in different electronic states.
Myogenic regulatory factors: Redundant or specific functions? Lessons from Xenopus
Authors: Chanoine Christophe , Della Gaspera Bruno , Charbonnier Frédéric 
Published: October 2004

AbstractThe discovery, in the late 1980s, of the MyoD gene family of muscle transcription factors has proved to be a milestone in understanding the molecular events controlling the specification and differentiation of the muscle lineage. From gene knock‐out mice experiments progressively emerged the idea that each myogenic regulatory factor (MRF) has evolved a specialized as well as a redundant role in muscle differentiation. To date, MyoD serves as a paradigm for the MRF mode of function. The features of gene regulation by MyoD support a model in which subprograms of gene expression are achieved by the combination of promoter‐specific regulation of MyoD binding and MyoD‐mediated binding of various ancillary proteins. This binding likely includes site‐specific chromatin reorganization by means of direct or indirect interaction with remodeling enzymes. In this cascade of molecular events leading to the proper and reproducible activation of muscle gene expression, the role and mode of function of other MRFs still remains largely unclear. Recent in vivo findings using the Xenopus embryo model strongly support the concept that a single MRF can specifically control a subset of muscle genes and, thus, can be substituted by other MRFs albeit with dramatically lower efficiency. The topic of this review is to summarize the molecular data accounting for a redundant and/or specific involvement of each member of the MyoD family in myogenesis in the light of recent studies on the Xenopus model. Developmental Dynamics 231:662–270, 2004. © 2004 Wiley‐Liss, Inc.
Mouse myotomes pairs exhibit left–right asymmetric expression of MLC3F and α‐skeletal actin
Authors: Golding Jon P. , Partridge Terence A. , Beauchamp Jonathan R. , King Tim , Brown Nigel A. , Gassmann Martin , Zammit Peter S. 
Published: October 2004

AbstractMost muscle originates from the myotomal compartment of the somites, paired structures flanking the neural tube. Whereas vertebrate embryos show molecular and morphological asymmetry about the left–right body axis, somitic myogenesis is thought to occur symmetrically. Here, we provide the first evidence that myotome pairs are transiently left–right asymmetric, with higher expression of α‐skeletal actin and myosin light chain 3F (MLC3F) on the left side between embryonic day 9.5–10.25. In iv mutants with situs inversus, the asymmetric expression of α‐skeletal actin and MLC3F was inverted, showing that this process is regulated by global left–right axis cues, initiated before gastrulation. However, although left–sided identity is later maintained by Pitx2 genes, we found that Pitx2c null embryos have normal left‐biased expression of α‐skeletal actin and MLC3F. Myotome asymmetry, therefore, is downstream of the iv mutation but upstream of, or unrelated to, the Pitx2c pathway. Developmental Dynamics 231:795–800, 2004. © 2004 Wiley‐Liss, Inc.
Early fin primordia of zebrafish larvae regenerate by a similar growth control mechanism with adult regeneration
Authors: Kawakami Atsushi , Fukazawa Taro , Takeda Hiroyuki 
Published: October 2004

AbstractSome vertebrate species, including urodele amphibians and teleost fish, have the remarkable ability of regenerating lost body parts. Regeneration studies have been focused on adult tissues, because it is unclear whether or not the repairs of injured tissues during early developmental stages have the same molecular base as that of adult regeneration. Here, we present evidence that a similar cellular and molecular mechanism to adult regeneration operates in the repair process of early zebrafish fin primordia, which are composed of epithelial and mesenchymal cells. We show that larval fin repair occurs through the formation of wound epithelium and blastema‐like proliferating cells. Cell proliferation is first induced in the distal‐most region and propagates to more proximal regions, as in adult regeneration. We also show that fibroblast growth factor signaling helps induce cell division. Our results suggest that the regeneration machinery directing cell proliferation in response to injury may exist from the early developmental stages. Developmental Dynamics 231:693–699, 2004. © 2004 Wiley‐Liss, Inc.
Interleukin‐11 signaling is required for the differentiation of natural killer cells at the maternal–fetal interface
Authors: Ain Rupasri , Trinh My‐Linh , Soares Michael J. 
Published: October 2004

AbstractInterleukin‐11 (IL‐11) is a multifunctional hematopoietic growth factor that has been implicated in the control of reproduction. Studies on IL‐11 receptor‐α (IL‐11Rα) ‐deficient mice showed that female mice are infertile due to defective decidualization. In this report, we evaluated the development of decidual cells, immune cells, and the vasculature associated with the implantation site of IL‐11Rα–deficient mice; with the aim of better understanding the nature of the fertility defect. Messenger RNAs for decidual differentiation, such as decidual prolactin‐related protein and prolactin‐like protein‐J are expressed in the IL‐11Rα mutant. However, the number of decidual cells expressing these genes is decreased in the mutant compared with the wild‐type control. Although, trophoblast cells differentiate and express placental lactogen‐I in the IL‐11Rα–deficient uterine environment, they fail to progress and expand in number. Defects in the organization of the decidual vasculature were also apparent in the IL‐11Rα mutant uterus. The most dramatic effect of IL‐11 signaling was on the hematopoietic environment of the uterine decidua. Differentiated/perforin‐expressing uterine natural killer (NK) cells were virtually absent from implantation sites of IL‐11Rα mutant mice. NK cell precursors were capable of homing to the IL‐11Rα–deficient uterus and a known regulator of NK cell differentiation; IL‐15 was expressed in the IL‐11Rα mutant uterus. Splenic NK cells from IL‐11Rα mutant mice were also able to respond to IL‐15 in vitro. Thus, the defect in NK precursor cell maturation was not intrinsic to the NK precursor cells but was dependent upon the tissue environment. In summary, IL‐11 signaling is required for decidual‐specific maturation of NK cells. Developmental Dynamics 231:700–708, 2004. © 2004 Wiley‐Liss, Inc.
Ventral otic cell lines as developmental models of auditory epithelial and neural precursors
Authors: Lawoko‐Kerali G. , Milo M. , Davies D. , Halsall A. , Helyer R. , Johnson C.M. , Rivolta M.N. , Tones M.A. , Holley M.C. 
Published: October 2004

AbstractConditionally immortal cell lines were established from the ventral otocyst of the Immortomouse at embryonic day 10.5 and selected to represent precursors of auditory sensory neural and epithelial cells. Selection was based upon dissection, tissue‐specific markers, and expression of the transcription factor GATA3. Two cell lines expressed GATA3 but possessed intrinsically different genetic programs under differentiating conditions. US/VOT‐E36 represented epithelial progenitors with potential to differentiate into sensory and nonsensory epithelial cells. US/VOT‐N33 represented migrating neuroblasts. Under differentiating conditions in vitro the cell lines expressed very different gene expression profiles. Expression of several cell‐ and tissue‐specific markers, including the transcription factors Pax2, GATA3, and NeuroD, differed between the cell lines in a pattern consistent with that observed between their counterparts in vivo. We suggest that these and other conditionally immortal cell lines can be used to study transient events in development against different backgrounds of cell competence. Developmental Dynamics 231:801–814, 2004. © 2004 Wiley‐Liss, Inc.
Expression of Nkx2‐5‐GFP bacterial artificial chromosome transgenic mice closely resembles endogenous Nkx2‐5 gene activity
Authors: Chi Xuan , Zhang Shu‐xing , Yu Wei , DeMayo Francesco J. , Rosenberg Susan M. , Schwartz Robert J. 
Published: October 2004

AbstractSummary: Mouse Nkx2‐5 gene is essential for early heart development and it is regulated by a complex array of regulatory modules. In order to establish an efficient in vivo system for mapping the Nkx2‐5 genomic locus for regulatory regions, we developed improved homologous recombination technology for use in Escherichia coli and then knocked an IRES‐hrGFP reporter gene into Nkx2‐5 gene in a 120 kb Nkx2‐5 bacterial artificial chromosome (BAC) clone. We employed the recombination genes redα and redβ under the pBAD promoter, which was specifically induced by the addition of L‐arabinose. Recombination was selected for by our universal targeting cassette which conferred kanamycin resistance in bacterial cells and neomycin resistance in mammalian cells. Transgenic mouse lines generated from this modified BAC clone closely resembled the endogenous Nkx2‐5 expression in the heart, pylorus sphincter, and spleen, but expression was not detected in the tongue. Nkx2‐5 BAC‐GFP expression was copy number‐dependent and locus site‐independent. BAC transgenics using the GFP reporter offers an efficient model system to study gene expression and regulation. genesis 35:220–226, 2003. © 2003 Wiley‐Liss, Inc.
Insulin‐like growth factor‐binding protein 6 inhibits survival and differentiation of rat oligodendrocyte precursor cells
Authors: Kühl Nicole M. , Hoekstra Dick , De Vries Hans , De Keyser Jacques 
Published: October 2004

AbstractInsulin‐like growth factor 1 (IGF‐1) is a growth and survival factor for oligodendrocyte lineage cells and promotes myelination. We demonstrate that IGF‐binding protein 6 (IGFBP‐6) is expressed and localized to the Golgi complex in rat oligodendrocyte precursor (O2A) cells. IGFBP‐6 mRNA showed a developmentally regulated expression pattern, displaying a transient decrease during early development, and enhanced levels upon cell maturation. IGFBP‐6 mRNA expression could be reduced by addition of basic fibroblast growth factor and progesterone while estrogen increased IGFBP‐6 mRNA. IGF‐1, platelet‐derived growth factor, and insulin had no effect. When added exogenously, IGFBP‐6 reduced O2A cell survival in the absence of IGF‐1 and inhibited IGF‐1‐stimulated survival in a partially IGF‐1‐dependent and partially IGF‐1‐independent fashion. In addition, IGFBP‐6 reduced the IGF‐stimulated expression of two myelin proteins, CNPase and MAG. Taken together, the data show that IGFBP‐6 is a new negative effector of oligodendrocyte survival and differentiation. © 2003 Wiley‐Liss, Inc.
Oligodendrocytes express functional A1 adenosine receptors that stimulate cellular migration
Authors: Othman Timothy , Yan Henglin , Rivkees Scott A. 
Published: October 2004

AbstractA1 adenosine receptors (A1ARs) exert important effects in the central nervous system. However, the expression and function of A1ARs in oligodendrocyte precursor cells (OPCs) and oligodendrocytes (OLGs) is unclear. To address this issue, we examined A1AR expression during different stages of oligodendrocyte development. Radioreceptor studies showed that membranes prepared from OPCs and OLGs expressed high‐affinity A1ARs with Kd values of 1.35 ± 0.33 and 1.2 ± 0.27 nM for [3H]CCPA, 1.17 ± 0.24 and 1.4 ± 0.34 nM for [3H]DPCPX, respectively. Bmax values were 64.31 ± 6.14 and 75 ± 6 fmol/mg protein for [3H]CCPA, and 153 ± 12 and 205 ± 17.8 fmol/mg protein for [3H]DPCPX, respectively. Activation of A1ARs using N6‐cyclopentyladenosine (CPA) reduced both forskolin‐ and N‐ethylcarboxyamidoadenosine (NECA)‐stimulated cAMP accumulation, but did not affect basal cAMP levels. Activation of A1ARs by CPA stimulated OPC migration, but did not affect cell viability, proliferation, or differentiation. These results show that OPCs and OLGs express functional A1ARs that can stimulate the migration of OPCs. © 2003 Wiley‐Liss, Inc.
Paranodal transverse bands are required for maintenance but not initiation of Nav1.6 sodium channel clustering in CNS optic nerve axons
Authors: Rasband Matthew N. , Taylor Christopher M. , Bansal Rashmi 
Published: October 2004

AbstractThe rapid, efficient, and faithful propagation of action potentials in myelinated nerve fibers depends on the appropriate complement and localization of ion channels. Recent work has suggested that specific voltage‐dependent sodium (Nav) channel isoforms are differentially regulated both spatially and temporally in a myelin‐dependent manner. Since the principal site of axoglial contact occurs at the paranode, we postulated that disrupted paranodal structure might result in altered nodal Nav channel isoform localization and clustering. We have used UDP‐galactose/ceramide galactosyl transferase (CGT)‐deficient mice, which form compact myelin and paranodal loops but lack the transverse bands normally found at the interface of the axon and overlying glial cell, to determine if this structure contributes to the signaling machinery responsible for clustering and localization of distinct Nav channel isoforms. We find that as in control animals, most mutant nodes of Ranvier had Nav1.6 in high‐density clusters in the peripheral and central nervous systems; the localization of Nav1.2 and the protein levels of Nav1.2 and Nav1.6 were also normal in the CGT‐deficient mouse. However, with increasing age, in the mutant mouse we observed a decrease in the total number of nodal Nav1.6 clusters, a decrease in the density of Nav1.6 channels at nodes, and an increase in the average size of the Nav1.6 clusters. Thus, transverse bands are not required for Nav1.6 clustering and localization at nodes or for exclusion of Nav1.2 from myelinated nerve fibers, but are required for the maintenance of nodal Nav1.6 cluster size and density. © 2003 Wiley‐Liss, Inc.
Comparative analysis of remyelinating potential of focal and intravenous administration of autologous bone marrow cells into the rat demyelinated spinal cord
Authors: Inoue Michio , Honmou Osamu , Oka Shinichi , Houkin Kiyohiro , Hashi Kazuo , Kocsis Jeffery D. 
Published: October 2004

AbstractThe remyelinating potential of autologous bone marrow cells was studied after direct injection and following intravenous injection into rats with a demyelinated lesion in the spinal cord. Both focal and intravenous injections of acutely isolated mononuclear bone marrow cell fractions resulted in varying degrees of remyelination. Suspensions of bone marrow cells collected from the same rat were delivered at varied concentrations (102 to 105 for direct injection and 104 to 107 for i.v. injections). The lesions were examined histologically 3 weeks after transplantation. Light microscopic examination revealed remyelination in the dorsal funiculus with both injection protocols, but the extent of remyelination was proportional to the number of injected cells. To attain the same relative density of remyelination achieved by direct injection, intravenous administration of cells required delivery of substantially more cells (two orders of magnitude). However, the availability of autologous bone marrow cells in large number and the potential for systemically delivering cells to target lesion areas without neurosurgical intervention suggest the potential utility of intravenous cell delivery as a prospective therapeutic approach in demyelinating disease. © 2003 Wiley‐Liss, Inc.
In vitro cytocompatibility assessment of β‐tricalcium phosphate/carboxymethyl‐chitin composite
Authors: Muramatsu Kazuaki , Nakajima Madoka , Kikuchi Masanori , Shimada Sawako , Sasaki Kiyoshi , Masuda Shingo , Yoshihara Yusuke 
Published: October 2004

AbstractA novel bioabsorbable bone substitute composed of a β‐tricalcium phosphate (β‐TCP) and a carboxymethyl‐chitin (CM‐chitin) sodium has been developed. Rabbit tibia defects (4 mm in diameter) were repaired after 4 weeks more effectively by the composite compared with a sham‐operation group. To further investigate the biological safety of the components, genotoxicity and carcinogenicity of an extract prepared from the composite were determined using four different in vitro assays. The main extract component was identified as CM‐chitin sodium [average molecular weight (Mw) ∼230 kDa] as determined by Fourier transform infrared spectroscopy and gel permeation chromatography analysis. The concentrations of P and Ca possibly derived from β‐TCP were 17.7 and 37.1 μg/g, respectively, as determined by inductively coupled plasma mass spectroscopy. Both the metabolic activation and nonactivation (−S9) systems of the rat microsome S9 fraction were used to perform a genotoxicity evaluation using the Ames test and chromosome aberration assay on Chinese hamster lung fibroblast cells treated with the extract. In these assays, no genotoxicity was detected with doses ≤5 mg/mL (maximum concentration). The cell transformation assay using BALB/c 3T3 cells and the metabolic cooperation assay with V79 cells both showed negative results for any tumor‐promoting activity caused by the extract (∼5 mg/mL). These results indicate that the bioabsorbable β‐TCP/CM‐chitin composite is a highly biocompatible bone substitute. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 635–643, 2004
Large‐volume leukapheresis using femoral venous access for harvesting peripheral blood stem cells with the Fenwal CS 3000 Plus from normal healthy donors: Predictors of CD34+ cell yield and collection efficiency
Authors: Sohn Sang Kyun , Kim Jong Gwang , Chae Yeo Soo , Kim Dong Hwan , Lee Nan Young , Suh Jang Soo , Lee Kyu Bo 
Published: October 2004

AbstractThe current paper reports on the predicting factors associated with satisfactory peripheral blood stem cell collection and the efficacy of large‐volume leukapheresis (LVL) using femoral vein catheterization to harvest PBSCs with Fenwal CS 3000 Plus from normal healthy donors for allogeneic transplantation. A total of 113 apheresis procedures in 57 patients were performed. The median number of MNCs, CD3+ cells, and CD34+ cells harvested per apheresis was 5.3 × 108/kg (range, 0.3–11.0 × 108/kg), 3.0 × 108/kg (range, 0.2–6.6 × 108/kg), and 7.9 × 106/kg (range, 0.1–188.9 × 106/kg), respectively. The median collection efficiency of MNCs and CD34+ cells was 49.8% and 49.7%, respectively. A highly significant correlation was found between the collected CD34+ cell counts and the pre‐apheresis WBC counts in the donors (P = 0.013), and between the collected CD34+ cell counts and the pre‐apheresis peripheral blood (PB) CD34+ cell counts (P<0.001). Harvesting at least >4 × 106/kg CD34+ cells from the 1st LVL was achieved in 44 (77.2%) out of 57 donors and in 19 (90.5%) out of 21 donors with a PB‐CD34+ cell count of >40/μl. There was no significant difference in the harvested MNC and CD34+ cell counts between the 1st and 2nd apheresis. The catheter‐related complications included catheter obstruction (n = 2) and hematoma at the insertion site (n = 3). Accordingly, LVL using femoral venous access for allogeneic PBSC collection from normal healthy donors would appear to be safe and effective. J. Clin. Apheresis 18:10–15, 2003. © 2003 Wiley‐Liss, Inc.