bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gene expression of nAChR, SNAP‐25 and GAP‐43 in skeletal muscles following botulinum toxin A injection: A study in rats
Authors: Ma Jianjun , Shen Jian , Lee Cassandra A. , Elsaidi Gamal A. , Smith Thomas L. , Walker Francis O. , Rushing Julia T. , Tan Kim H. , Koman L. Andrew , Smith Beth P. 
Published: December 2004

AbstractPurpose: Botulinum toxin A (BoNT‐A) is used to manage spasticity in cerebral palsy. BoNT‐A cleaves SNAP‐25 protein, blocking acetylcholine release and weakening the muscle. Nicotinic acetylcholine receptors (nAChR) including alpha, beta, delta, gamma, and epsilon subunits, and GAP‐43 protein are associated with functional recovery of neuromuscular junctions (NMJ) following BoNT‐A. To better understand the mechanism behind this functional recovery, this study attempted to (1) document changes in NMJ morphometry following BoNT‐A, and (2) determine the gene expression of nAChR subunits, SNAP‐25, and GAP‐43 protein.Methods: In this rat study (46 rats), 6 units/kg body weight of BoNT‐A was injected into the gastrocnimus. NMJ morphometry and the time course of gene expression of nAChR subunits, SNAP‐25, and GAP‐43 were evaluated up to 1 year post‐injection.Results: NMJ morphometry: gutter depth was reduced vs. the control side at two months, and normalizing by 6 months following BoNT. nAChR alpha mRNA and gamma mRNA increased by 3 days, peaked at 7 days and returned to control levels; delta mRNA peaked at 3 days. Epsilon mRNA peaked by 7 days. SNAP‐25 mRNA increased from 60 to 90 days, returning to control levels by 6 months. GAP‐43 mRNA was unchanged.Conclusions: Specific nAChR subunit mRNA expression up‐regulates and then returns to normal within two weeks, preceding changes in NMJ morphometry. Although GAP‐43 participates in nerve sprouting, no increase of GAP‐43 mRNA occurred following BoNT‐A. Delayed up‐regulation of SNAP‐25 mRNA might be associated with muscle functional recovery. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Type I and II collagen regulation of chondrogenic differentiation by mesenchymal progenitor cells
Authors: Chen C. W. , Tsai Y. H. , Deng W. P. , Shih S. N. , Fang C. L. , Burch J. G. , Chen W. H. , Lai W. F. 
Published: December 2004

AbstractChondrogenic differentiation by mesenchymal progenitor cells (MPCs) is associated with cytokines such as transforming growth factor‐beta 1 (TGF‐β1) and dexamethasone. Extracellular matrix (ECM) also regulates the differentiation by MPCs. To define whether ECM plays a functional role in regulation of the chondrogenic differentiation by MPCs, an in vitro model was used. That model exposed to dexamethasone, recombinant human TGF‐β1(rhTGF‐β1) and collagens. The results showed that MPCs incorporated with dexamethasone and rhTGF‐β1 increased proliferation and expression of glycosaminoglycan (GAG) after 14 days. Type II collagen enhanced the GAG synthesis, but did not increase alkaline phosphatase (ALP) activity. When adding dexamethasone and rhTGF‐β1 MPCs increased mRNA expression of Sox9. Incorporation with type II collagen, dexamethasone and rhTGF‐β1, MPCs induced mRNA expression of aggrecan and enhanced levels of type II collagen, and Sox9 mRNA. In contrast, incorporation with type I collagen, dexamethasone and rhTGF‐β1 MPCs reduced levels of aggrecan, and Sox9 mRNA, and showed no type II collagen mRNA. Altogether, these results indicate that type I and II collagen, in addition to the cytokine effect, may play a functional role in regulating of chondrogenic differentiation by MPCs. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Hi and Galaxy Formation in Loose Groups
Authors: Pisano Daniel J. 
Published: December 2004

AbstractModels of hierarchical galaxy formation predict that large numbers of low-mass, dark matter halos remain around galaxies today. These models predict an order of magnitude more halos than observed stellar satellites in the Local Group. One possible solution to this discrepancy is that the high-velocity clouds (HVCs) around the Milky Way may be associated with the excess dark matter halos and be the gaseous remnants of the galaxy formation process. If this is the case, then analogues to the HVCs should be visible in other groups. In this paper, I review the observations of Hi clouds lacking stars around other galaxies and in groups, present early results from our Hi survey of loose groups analogous to the Local Group, and discuss implications for the nature of HVCs and galaxy formation.
Identification of the Arabidopsis Palmitoyl-Monogalactosyldiacylglycerol Δ7-Desaturase Gene FAD5, and Effects of Plastidial Retargeting of Arabidopsis Desaturases on the fad5 Mutant Phenotype
Authors: Heilmann Ingo , Mekhedov Sergei , King Barbara , Browse John , Shanklin John 
Published: December 2004

Abstract
Hexadeca 7,10,13-trienoic acid (16:3Δ7,10,13) is one of the most abundant fatty acids in Arabidopsis (Arabidopsis thaliana) and a functional component of thylakoid membranes, where it is found as an sn-2 ester of monogalactosyldiacylglycerol. The Arabidopsis fad5 mutant lacks activity of the plastidial palmitoyl-monogalactosyldiacylglycerol Δ7-desaturase FAD5, and is characterized biochemically by the absence of 16:3Δ7,10,13 and physiologically by reduced chlorophyll content and a reduced recovery rate after photoinhibition. While the fad5 mutation has been mapped, the FAD5 gene was not unambiguously identified, and a formal functional characterization by complementation of fad5 mutant phenotypes has not been reported. Two candidate genes (At3g15850 and At3g15870) predicted to encode plastid-targeted desaturases at the fad5 chromosomal locus were cloned from fad5 plants and sequenced. A nonsense mutation changing codon TGG (Trp-98) into TGA (stop) was identified in At3g15850 (ADS3), whereas the fad5 At3g15870 allele was identical to wild type (after correction of a sequencing error in the published wild-type genomic At3g15870 sequence). Expression of a genomic clone or cDNA for wild-type At3g15850 conferred on fad5 plants the ability to synthesize 16:3Δ7,10,13 and restored leaf chlorophyll content. Arabidopsis carrying a T-DNA insertion in At3g15870 had wild-type levels of both 16:3Δ7,10,13 and chlorophyll. Together, these data formally prove that At3g15850 is FAD5. Interestingly, the fad5 phenotype was partially complemented when extraplastidial Δ9-desaturases of the Arabidopsis desaturase (ADS) family were expressed as fusions with a plastidial transit peptide. Tight correlation between leaf 16:3Δ7,10,13 levels and chlorophyll content suggests a role for plastidial fatty acid desaturases in thylakoid formation.
The Arabidopsis ATR1 Myb Transcription Factor Controls Indolic Glucosinolate Homeostasis
Authors: Celenza John L. , Quiel Juan A. , Smolen Gromoslaw A. , Merrikh Houra , Silvestro Angela R. , Normanly Jennifer , Bender Judith 
Published: December 2004

Abstract
Plants derive a number of important secondary metabolites from the amino acid tryptophan (Trp), including the growth regulator indole-3-acetic acid (IAA) and defense compounds against pathogens and herbivores. In previous work, we found that a dominant overexpression allele of the Arabidopsis (Arabidopsis thaliana) Myb transcription factor ATR1, atr1D, activates expression of a Trp synthesis gene as well as the Trp-metabolizing genes CYP79B2, CYP79B3, and CYP83B1, which encode enzymes implicated in production of IAA and indolic glucosinolate (IG) antiherbivore compounds. Here, we show that ATR1 overexpression confers elevated levels of IAA and IGs. In addition, we show that an atr1 loss-of-function mutation impairs expression of IG synthesis genes and confers reduced IG levels. Furthermore, the atr1-defective mutation suppresses Trp gene dysregulation in a cyp83B1 mutant background. Together, this work implicates ATR1 as a key homeostatic regulator of Trp metabolism and suggests that ATR1 can be manipulated to coordinately control the suite of enzymes that synthesize IGs.
Characterization of Antirrhinum Petal Development and Identification of Target Genes of the Class B MADS Box GeneDEFICIENS [W]
Authors: Bey Melanie , Stüber Kurt , Fellenberg Kurt , Schwarz-Sommer Zsuzsanna , Sommer Hans , Saedler Heinz , Zachgo Sabine 
Published: December 2004

AbstractThe class B MADS box transcription factors DEFICIENS (DEF) and GLOBOSA (GLO) of Antirrhinum majus together control the organogenesis of petals and stamens. Toward an understanding of how the downstream molecular mechanisms controlled by DEF contribute to petal organogenesis, we conducted expression profiling experiments using macroarrays comprising &gt;11,600 annotated Antirrhinum unigenes. First, four late petal developmental stages were compared with sepals. More than 500 ESTs were identified that comprise a large number of stage-specifically regulated genes and reveal a highly dynamic transcriptional regulation. For identification of DEF target genes that might be directly controlled by DEF, we took advantage of the temperature-sensitive def-101 mutant. To enhance the sensitivity of the profiling experiments, one petal developmental stage was selected, characterized by increased transcriptome changes that reflect the onset of cell elongation processes replacing cell division processes. Upon reduction of the DEF function, 49 upregulated and 52 downregulated petal target genes were recovered. Eight target genes were further characterized in detail by RT-PCR and in situ studies. Expression of genes responding rapidly toward an altered DEF activity is confined to different petal tissues, demonstrating the complexity of the DEF function regulating diverse basic processes throughout petal morphogenesis.
Arabidopsis WPP-Domain Proteins Are Developmentally Associated with the Nuclear Envelope and Promote Cell Division[W]
Authors: Patel Shalaka , Rose Annkatrin , Meulia Tea , Dixit Ram , Cyr Richard J. , Meier Iris 
Published: December 2004

AbstractThe nuclear envelope (NE) acts as a selective barrier to macromolecule trafficking between the nucleus and the cytoplasm and undergoes a complex reorganization during mitosis. Different eukaryotic kingdoms show specializations in NE function and composition. In contrast with vertebrates, the protein composition of the NE and the function of NE proteins are barely understood in plants. MFP1 attachment factor 1 (MAF1) is a plant-specific NE-associated protein first identified in tomato (Lycopersicon esculentum). Here, we demonstrate that two Arabidopsis thaliana MAF1 homologs, WPP1 and WPP2, are associated with the NE specifically in undifferentiated cells of the root tip. Reentry into cell cycle after callus induction from differentiated root segments reprograms their NE association. Based on green fluorescent protein fusions and immunogold labeling data, the proteins are associated with the outer NE and the nuclear pores in interphase cells and with the immature cell plate during cytokinesis. RNA interference–based suppression of the Arabidopsis WPP family causes shorter primary roots, a reduced number of lateral roots, and reduced mitotic activity of the root meristem. Together, these data demonstrate the existence of regulated NE targeting in plants and identify a class of plant-specific NE proteins involved in mitotic activity.
Diversification and Alteration of Recognition Specificity of the Pollen Ligand SP11/SCR in Self-Incompatibility of Brassica and Raphanus[W]
Authors: Sato Yutaka , Okamoto Shunsuke , Nishio Takeshi 
Published: December 2004

AbstractThe recognition specificity of the pollen ligand of self-incompatibility (SP11/SCR) was investigated using Brassica rapa transgenic plants expressing SP11 transgenes, and SP11 of Raphanus sativus S-21 was found to have the same recognition specificity as that of B. rapa S-9. In a set of three S haplotypes, whose sequence identities of SP11 and SRK are fairly high, R. sativus S-6 showed the same recognition specificity as Brassica oleracea S-18 and a slightly different specificity from B. rapa S-52. B. oleracea S-18, however, showed a different specificity from B. rapa S-52. Using these similar S haplotypes, chimeric SP11 proteins were produced by domain swapping. Bioassay using the chimeric SP11 proteins revealed that the incompatibility response induction activity was altered by the replacement of Region III and Region V. Pollen grains of Brassica transgenic plants expressing chimeric SP11 of the B. oleracea SP11-18 sequence with Region III and Region V from B. rapa SP11-52 (chimeric BoSP11-18[52]) were partially incompatible with the B. rapa S-52 stigmas, and those expressing the R. sativus SP11-6 sequence with Region III and Region V from B. rapa SP11-52 (chimeric RsSP11-6[52]) were completely incompatible with the stigmas having B. rapa S-52. However, the transgenic plant expressing chimeric RsSP11-6(52) also showed incompatibility with B. oleracea S-18 stigmas. These results suggest that Regions III and Region V of SP11 are important for determining the recognition specificity, but not the sole determinant. A possible process of the generation of a new S haplotype is herein discussed.
LIGHT INDEPENDENT CARBON FIXATION BY MARINE MACROALGAE1
Authors: Kremer Bruno P. 
Published: December 2004

ABSTRACTSeveral marine macroalgae representative of the Chlorophyceae, Rhodophyceae and Phaeophyceae were investigated for their potentials of photosynthesis and light independent (dark) carbon fixation. In addition, the activities of ribulose‐1,5‐bisphosphate carboxylase (RubP‐C; EC 4.1.1.39) and of phosphoenolpyruvate carboxykinase (PEP‐CK; EC 4.1.1.32) were studied. In contrast to the green and red algae investigated, all brown algae exhibited comparably high rates of dark fixation accounting for up to 20% of photosynthetic carbon uptake. These observations are confirmed by the activities of RubP‐C and PEP‐CK measured after extraction from different species and thallus regions. Dark fixed 14C was mainly recovered from aspartate, citrate, malate, glutamate, and alanine. Appreciable amounts of 14C were incorporated into insoluble (polymeric) constituents even after relatively short periods of dark fixation.
Low Temperature Stimulates α‐Melanophore‐Stimulating Hormone Secretion and Inhibits Background Adaptation in Xenopus laevis
Authors: Tonosaki Y. , Cruijsen P. M. J. M. , Nishiyama K. , Yaginuma H. , Roubos E. W. 
Published: December 2004

AbstractIt is well‐known that α‐melanophore‐stimulating hormone (α‐MSH) release from the amphibian pars intermedia (PI) depends on the light condition of the animal's background, permitting the animal to adapt the colour of its skin to background light intensity. In the present study, we carried out nine experiments on the effect of low temperature on this skin adaptation process in the toad Xenopus laevis, using the skin melanophore index (MI) bioassay and a radioimmunoassay to measure skin colour adaptation and α‐MSH secretion, respectively. We show that temperatures below 8 °C stimulate α‐MSH secretion and skin darkening, with a maximum at 5 °C, independent of the illumination state of the background. No significant stimulatory effect of low temperature on the MI and α‐MSH plasma contents was noted when the experiment was repeated with toads from which the neurointermediate lobe (NIL) had been surgically extirpated. This indicates that low temperature stimulates α‐MSH release from melanotrope cells located in the PI. An in vitro superfusion study with the NIL demonstrated that low temperature does not act directly on the PI. A possible role of the central nervous system in cold‐induced α‐MSH release from the PI was tested by studying the hypothalamic expression of c‐Fos (as an indicator for neuronal activity) and the coexistence of c‐Fos with the regulators of melanotrope cell activity, neuropeptide Y (NPY) and thyrotrophin‐releasing hormone (TRH), using double fluorescence immunocytochemistry. Upon lowering temperature from 22 °C to 5 °C, in white‐adapted animals c‐Fos expression decreased in NPY‐producing suprachiasmatic‐melanotrope‐inhibiting neurones (SMIN) in the ventrolateral area of the suprachiasmatic nucleus (SC) but increased in TRH‐containing neurones of the magnocellular nucleus. TRH is known to stimulate melanotrope α‐MSH release. We conclude that temperatures around 5 °C inactivate the SMIN in the SC and activate TRH‐neurones in the magnocellular nucleus, resulting in enhanced α‐MSH secretion from the PI, darkening the skin of white‐adapted X. laevis.
Mechanisms of N‐methyl‐d‐Aspartate Receptor Inhibition by Melatonin In the Rat Striatum
Authors: Escames G. , León J. , López L. C. , Acuña‐Castroviejo D. 
Published: December 2004

Abstract N‐methyl‐d‐aspartate (NMDA) receptor activation comprises multiple regulatory sites controlling Ca2+ influx into the cell. NMDA‐induced increases in intracellular [Ca+2] lead to nitric oxide (NO) production through activation of neuronal NO synthase (nNOS). Melatonin inhibits either glutamate or NMDA‐induced excitation, but the mechanism of this inhibition is unknown. In the present study, the mechanism of melatonin action in the rat striatum was studied using extracellular single unit recording of NMDA‐dependent neuronal activity with micro‐iontophoresis. Melatonin inhibited neuronal excitation produced by either NMDA or l‐arginine. The effects of both NMDA and l‐arginine were blocked by nitro‐l‐arginine methyl ester, suggesting that nNOS participates in responses to NMDA. However, excitation of NMDA‐sensitive neurones induced by the NO donor sodium nitroprusside was only slightly modified by melatonin. Melatonin iontophoresis also counteracted excitation induced by tris(2‐carboxyethyl)phosphine hydrochloride, showing that the redox site of the NMDA receptor may be a target for melatonin action. The lack of effects of the membrane melatonin receptor ligands luzindole, 4‐phenyl‐2‐propionamidotetralin and 5‐methoxycarbonylamino‐N‐acetyltryptamine, and the nuclear melatonin ligand, CGP 52608, a thiazolidine dione, excluded the participation of known membrane and nuclear receptors for melatonin. The data suggest that inhibition of NMDA‐dependent excitation by melatonin involves both nNOS inhibition and redox site modulation.
Identification of allergens responsible for canine cutaneous adverse food reactions to lamb, beef and cow's milk
Authors: MARTÍN ÁUREA , SIERRA MARÍA‐PAZ , GONZÁLEZ JOSÉ L. , ARÉVALO MARÍA‐ÁNGELES 
Published: December 2004

Abstract Lamb, beef and cow's milk are common causes of cutaneous adverse food reactions in dogs. The aim of this study was to identify the proteins responsible for cutaneous adverse reactions to these foods. Ten dogs with allergen‐specific serum immunoglobulin (Ig)E to lamb, beef and cow's milk were included in the study. These dogs had been diagnosed with cutaneous adverse food reactions by convincing clinical history and food‐elimination diet trials followed by challenge exposure. Sera were analysed by enzyme‐linked immunosorbent assay with bovine proteins and SDS–PAGE immunoblots with lamb, beef and cow's milk extracts. All the dogs had specific IgE against bovine IgG, and it was the only protein in the cow's milk extract that bound IgE from the sera studied. In the lamb and beef extracts, the major allergens recognized by the specific IgE of most sera had molecular masses between 51 and 58 kDa, which were identified as phosphoglucomutase and the IgG heavy chain. Other IgE‐binding proteins with molecular masses of 27, 31, 33, 37 and 42 kDa were also detected with some sera. Our results indicate that bovine IgG is a major allergen in cow's milk and hence it appears to be a source of cross‐reactivity with beef and probably with lamb because of the high homology with ovine immunoglobulins. These results are similar to those found for meat allergy in humans. However, this is the first time that phosphoglucomutase has been identified as an important allergen involved in allergic reactions to lamb and beef.
Pectin in pig nutrition, a comparative review
Authors: Drochner W. , Kerler A. , Zacharias B. 
Published: December 2004

SummaryA comprehensive review is given on pectin effects in pigs. Its effects on feed passage and digestion in the small intestine, the composition of ileal digesta and fermentation in the colon are described. Pectins promote fermentation at the terminal ileum and in the first part of the colon. It is shown, that pectin opposite to cellulose is degraded to high extents in the colon. Dietetic effects in relation to composition of ileocaecal digesta, endogenous secretions, buffering and pH‐stability, high fermentability of organic matter in the colon and resulting volatile fatty acids (VFA) in the cranial part of the colon and even its possible interactions to colonization of the gut by infectious bacteria are described. Pectin effects concerning volume of the intestinal tract, distribution of VFA and lactic acid, role of endogenous secretions are described. The negative effect of pectins on praecaecal digestibility, their high degradation rates in the large intestine and consequences for their dietetic effects are discussed.
An Experimental Infection (II) to Investigate the Importance of Indirect Classical Swine Fever Virus Transmission by Excretions and Secretions of Infected Weaner Pigs
Authors: Ribbens S. , Dewulf J. , Koenen F. , Laevens H. , Mintiens K. , de Kruif A. 
Published: December 2004

SummaryAn experiment was set up to investigate the role of excretions and secretions in the indirect transmission of classical swine fever virus (CSFV). In five small pens, 10 weaner pigs (two pigs per pen) were housed and inoculated with CSFV. Experimental infection was successful in all pigs. The infected pigs were kept in the pens for a period of 15 days after which the pens were depopulated and pigs were killed. At the moment of depopulation, all inoculated pigs were visibly clinically diseased and had high fever. Ten hours later the same pens were repopulated with five pairs of susceptible pigs. From inoculation onwards and especially between depopulation and restocking, the pens were neither cleaned nor disinfected. Four days post‐repopulation, three of the susceptible pigs were detected positive on virus isolation. A fourth pig was detected positive 2 days later. Later on, the remaining pigs also became infected, most probably due to contact and between pen infections. It can be concluded that transmission of the virus via excretions and secretions succeeded in four of 10 pigs. This result indicates that transmission of CSFV via excretions and secretions can be of importance in a late, clinical stage of disease.
Mycobacterium avium ssp. paratuberculosis – Combined Serological Testing and Classification of Individual Animals and Herds
Authors: Böttcher J. , Gangl A. 
Published: December 2004

SummarySeveral serological tests for detection of antibodies to Mycobacterium avium ssp. paratuberculosis, which is the causative agent of Johne's disease are validated, some of which are available commercially. These tests differ in sensitivity and specificity. Test results reported to farmers or veterinarians are therefore dependent upon the test in use. In the present study, three commercially available tests are used to test 2748 bovine sera from 119 Bavarian herds serologically. Serological results are compared with individual animals and on herd level. A scheme for serological testing and classification of herds as well as of individual animals based on a combination of serological test results is proposed.