bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Teosinte Cytoplasmic Genomes on Maize Phenotype
Authors: Allen James O 
Published: February 2005

Abstract
Determining the contribution of organelle genes to plant phenotype is hampered by several factors, including the paucity of variation in the plastid and mitochondrial genomes. To circumvent this problem, evolutionary divergence between maize (Zea mays ssp. mays) and the teosintes, its closest relatives, was utilized as a source of cytoplasmic genetic variation. Maize lines in which the maize organelle genomes were replaced through serial backcrossing by those representing the entire genus, yielding alloplasmic sublines, or cytolines were created. To avoid the confounding effects of segregating nuclear alleles, an inbred maize line was utilized. Cytolines with Z. mays teosinte cytoplasms were generally indistinguishable from maize. However, cytolines with cytoplasm from the more distantly related Z. luxurians, Z. diploperennis, or Z. perennis exhibited a plethora of differences in growth, development, morphology, and function. Significant differences were observed for 56 of the 58 characters studied. Each cytoline was significantly different from the inbred line for most characters. For a given character, variation was often greater among cytolines having cytoplasms from the same species than among those from different species. The characters differed largely independently of each other. These results suggest that the cytoplasm contributes significantly to a large proportion of plant traits and that many of the organelle genes are phenotypically important.
Spinocerebellar ataxia type 26 maps to chromosome 19p13.3 adjacent to SCA6
Authors: Yu Guo‐Yun , Howell Michael J. , Roller Matthew J. , Xie Ting‐Dong , Gomez Christopher M. 
Published: February 2005

AbstractThe dominantly inherited spinocerebellar ataxias (SCA) are a clinically and genetically heterogeneous group of neurodegenerative disorders characterized by progressive gait ataxia, upper limb incoordination, and dysarthria. We studied a six‐generation kindred of Norwegian ancestry with pure cerebellar ataxia inherited in an autosomal dominant pattern. All affected family members had a slowly progressive cerebellar ataxia, with an age of onset range from 26 to 60 years. Brain magnetic resonance imaging study of 11 affected patients showed that atrophy was confined to the cerebellum. After excluding all the known SCAs using linkage analysis or direct mutation screen, we conducted a genomewide genetic linkage scan. With the aid of a novel linkage analysis strategy, we found linkage between the disease locus and marker D19S591 and D19S1034. Subsequent genetic and clinical analysis identified a critical region of 15.55cM interval on chromosome 19p13.3, flanked by markers D19S886 and D19S894, and have established a new genetic locus designated SCA26. The SCA26 locus is adjacent to the genes for Cayman ataxia and SCA6. The region consists of 3.3 million base pairs (Mb) of DNA sequences with approximately 100 known and predicted genes. Identification of the responsible gene for SCA26 ataxia will provide further insight into mechanisms of neurodegeneration. Ann Neurol 2005;57:349–354
Fewer thymic changes in MuSK antibody‐positive than in MuSK antibody‐negative MG
Authors: Leite Maria Isabel , Ströbel Philipp , Jones Margaret , Micklem Kingsley , Moritz Regina , Gold Ralf , Niks Erik H. , Berrih‐Aknin Sonia , Scaravilli Francesco , Canelhas Aurea , Marx Alexander , Newsom‐Davis John , Willcox Nick , Vincent Angela 
Published: February 2005

AbstractIn generalized myasthenia gravis (MG) patients without detectable acetylcholine receptor (AChR) antibodies (SNMG), the thymus is often reported as “normally involuted.” We analyzed thymic compartments in 67 patients with generalized MG, with AChR antibodies (AChR+, n = 23), with muscle‐specific kinase (MuSK) antibodies (MuSK+, n = 14) or with neither (MuSK−, n = 30), and in 11 non‐MG controls. Four of 14 MuSK+ thymi had rare small germinal centers, but overall they were not different from age‐matched controls. However, approximately 75% MuSK− samples showed lymph node–type infiltrates similar to those in AChR+ patients, but with fewer germinal centers. These variations may explain some apparent differences in responses to thymectomy in SNMG. Ann Neurol 2005;57:444–448
Interaction of α‐synuclein and tau genotypes in Parkinson's disease
Authors: Mamah Catherine E. , Lesnick Timothy G. , Lincoln Sarah J. , Strain Kari J. , de Andrade Mariza , Bower James H. , Ahlskog J. Eric , Rocca Walter A. , Farrer Matthew J. , Maraganore Demetrius M. 
Published: February 2005

AbstractTo determine whether the microtubule‐associated protein tau (MAPT) and α‐synuclein (SNCA) genes interact to confer Parkinson's disease (PD) susceptibility, we conducted a study of 557 case–control pairs. There was an increased risk of PD for persons with either SNCA 261/261 or MAPT H1/H1 genotypes as compared with persons with neither (odds ratio, 1.96; 95% confidence interval, 1.34–2.86; p = 0.0003). However, the combined effect of the two genotypes was the same as for either of the genotypes alone (separate and equal). These findings are consistent with in vitro experiments that revealed tau‐mediated fibrillization of α‐synuclein protein at low concentrations (dose threshold effect). Ann Neurol 2005;57:439–443
Acute tetrodotoxin‐induced neurotoxicity after ingestion of puffer fish
Authors: Kiernan Matthew C. , Isbister Geoffrey K. , Lin Cindy S.‐Y. , Burke David , Bostock Hugh 
Published: February 2005

AbstractThis study documents the effects of puffer‐fish poisoning on peripheral nerve. Excitability measurements investigated membrane properties of sensory and motor axons in four patients. The median nerve was stimulated at the wrist, with compound muscle potentials recorded from abductor pollicis brevis and compound sensory potentials from digit 2. Stimulus–responses, strength–duration time constant (τSD), threshold electrotonus, and current–threshold relations were recorded. The urine of each patient tested positive for tetrodotoxin. Compared with controls, axons were of higher threshold, compound muscle action potentials and compound sensory nerve action potentials were reduced in amplitude, latency was prolonged, and τSD was reduced. In recovery cycles, refractoriness, superexcitability, and late subexcitability were decreased. Threshold electrotonus of motor axons exhibited distinctive abnormalities with less threshold decline than normal on depolarization and greater threshold increase on hyperpolarization (p < 0.0005 for each patient). The changes in excitability were reproduced in a mathematical model by reducing sodium (Na+) permeabilities by a factor of two. This study confirms that the neurotoxic effects of puffer‐fish poisoning can be explained by tetrodotoxin blockade of Na+ channels. It demonstrates the ability of noninvasive nerve excitability studies to detect Na+ channel blockade in vivo and also the utility of mathematical modeling to aid interpretation of altered excitability properties in disease. Ann Neurol 2005;57:339–348
Assessment of nerve degeneration by gadofluorine M–enhanced magnetic resonance imaging
Authors: Bendszus Martin , Wessig Carsten , Schütz Ansgar , Horn Tanja , Kleinschnitz Christoph , Sommer Claudia , Misselwitz Bernd , Stoll Guido 
Published: February 2005

AbstractNerve injury represents a major cause of disability. In the peripheral nervous system, nerves have the capacity to regrow but within weeks after injury, it is impossible to clarify whether proper regeneration is under way or is failing. In this experimental study, we report on a novel tool to assess nerve outgrowth in vivo. After systemic application, the novel gadolinium‐based magnetic resonance (MR) contrast agent Gadofluorine M (Gf) selectively accumulated and persisted in nerve fibers undergoing Wallerian degeneration causing bright contrast on T1‐weighted MR images. Gf enhancement on MR imaging was present already at 48 hours within the entire nerve segments undergoing Wallerian degeneration, and subsequently disappeared from proximal to distal parts in parallel to regrowth of nerve fibers. Most importantly, Gf enhancement persisted in nonregenerating, permanently transected nerves. Our novel Gf‐based MR imaging methodology holds promise for clinical use to bridge the diagnostic gap between nerve injury and completed nerve regeneration, and to determine the necessity for neurolysis and engraftment if spontaneous regeneration is not successful. Ann Neurol 2005;57:388–395
Mutations in senataxin responsible for Quebec cluster of ataxia with neuropathy
Authors: Duquette Antoine , Roddier Katel , McNabb‐Baltar Julia , Gosselin Isabelle , St‐Denis Anik , Dicaire Marie‐Josée , Loisel Lina , Labuda Damian , Marchand Luc , Mathieu Jean , Bouchard Jean‐Pierre , Brais Bernard 
Published: February 2005

AbstractSenataxin recently was identified as the mutated gene in ataxia‐oculomotor apraxia 2, which is characterized by ataxia, oculomotor apraxia, and increased α‐fetoprotein levels. In this study, we evaluated 24 ataxic patients from 10 French‐Canadian families. All cases have a homogeneous phenotype consisting of a progressive ataxia appearing between 2 and 20 (mean age, 14.8) years of age with associated dysarthria, saccadic ocular pursuit, distal amyotrophy, sensory and motor neuropathy, and increased α‐fetoprotein levels but absence of oculomotor apraxia. Linkage disequilibrium was observed with markers in the ataxia‐oculomotor apraxia 2 locus on chromosome 9q34. We have identified four mutations in senataxin in the French‐Canadian population including two novel missense mutations: the 5927T→G mutation changes the leucine encoded by codon 1976 to an arginine in the helicase domain (L1976R), and the 193G→A mutation changes a glutamic acid encoded by codon 65 into a lysine in the N‐terminal domain of the protein (E65K). The common L1976R mutation is shared by 17 of 20 (85%) carrier chromosomes. The study of this large French‐Canadian cohort better defines the phenotype of this ataxia and presents two novel mutations in senataxin including the more common founder mutation in the French‐Canadian population. Ann Neurol 2005;57:408–414
Synthesis and characterization of thermosensitive composite microsphere latex
Authors: Yi Changfeng , Xu Zushun 
Published: February 2005

AbstractMonodisperse aqueous latex dispersions, prepared from mixtures of styrene, N‐isopropylacrylamide, and N,N′‐methylenebisacrylamide, were characterized. Thermosensitive composite microspheres with diameters greater than 1.0 μm, consisting of a polystyrene core and a poly(N‐isopropylacrylamide) shell, were prepared. The morphology of the composite microspheres was observed with transmission electron microscopy, and the particle size of the composite microspheres was estimated with dynamic light scattering. The thermosensitive properties of the composite microspheres were evaluated via the hydrodynamic size of the composite microspheres. The particle size of the composite microspheres decreased with increasing temperature. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 824–828, 2005
Sharkskin mechanism of high‐impact polystyrene (HIPS) and rheological behavior of HIPS/TiO2 composites
Authors: Wang Xin , Wang Zhaobo , Wu Qiye 
Published: February 2005

AbstractThe rheological behaviors of high‐impact polystyrene (HIPS) and HIPS/TiO2 composites were investigated by use of a rheometer in the present article. HIPS exhibited a constant critical stress of the sharkskin in various temperatures, and the analysis indicated that the mechanism of sharkskin of HIPS was wall–slip and its special temperature dependency was determined by weak wall–melt adsorption. The experimental results also showed that the introduction of TiO2 into HIPS only slightly influenced the apparent viscosity (ηa) of the composites. Moreover, TiO2 exhibited an unusual effect on the non‐Newtonian index of the composites at high shear rate. Both phenomena indicated the increase of inner free volume induced by TiO2 in molecularly rigid HIPS. Moreover, it was noteworthy that a featured stress could be used to label the dispersion of TiO2 in the HIPS matrix, and the numeric affinity of this featured stress and the critical stress of sharkskin revealed that both processes were relevant to the same molecular relaxation. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 802–807, 2005
Evidence for a presynaptic action of chlordimeform at the insect neuromuscular junction
Authors: Yamamoto Daisuke , Washio Hiroshi , Fukami Jun‐Ichi 
Published: February 2005

AbstractThe mechanism of action of chlordimeform on the mealworm nerve‐muscle preparation was studied with microelectrodes. Chlordimeform affected neither the mean amplitude nor the frequency of spontaneous miniature excitatory postsynaptic potentials. Extracellular focal recordings show that in the presence of 0.8 mM chlordimeform the presynaptic spike is almost unchanged, but the quantal content for evoked transmitter release is reduced. It is suggested that chlordimeform decreases the influx of calcium at the presynaptic terminal during the active phase of the nerve terminal action potential, thereby inhibiting evoked transmitter release.
Conversion of ecdysone and 20‐Hydroxyecdysone into 26‐OIC derivatives is a major pathway in larvae and pupae of species from three insect orders
Authors: Lafont René , Blais Catherine , Beydon Philippe , Modde Jean‐François , Enderle Ulrike , Koolman Jan 
Published: February 2005

AbstractInsects convert ecdysone and 20‐hydroxyecdysone into their corresponding 26‐oic derivatives, named ecdysonoic acid and 20‐hydroxyecdysonoic acid respectively. The conversion takes piace in several tissues and can either be the only pathway for converting ecdysone into highly polar ecdysteroids, or coexist with various conjugating mechanisms.20‐Hydroxyecdysonoic acid was isolated from Pieris brassicae pupae as its methyl ester derivative. Its chemical structure was identified by Cl/D mass spectrometry and compared with a synthetic compound (20‐hydroxy‐25‐deoxyecdysonoic acid) chemically prepared by oxidation of inokosterone (20,26‐dihydroxy‐25‐deoxyecdysone). Natural ecdysonoic acids appear to exist as a mixture of 25R and 25S isomers.The significance of this pathway is discussed in comparison with similar reactions occuring in the metabolism of steroid hormones in vertebrates.
Absence of phytosterol dealkylation and identification of the major ecdysteroid as makisterone A in Dysdercus fasciatus (Heteroptera, Pyrrhocoridae)
Authors: Gibson J. M. , Majumder M. S. I. , Mendis A. H. W. , Rees H. H. 
Published: February 2005

AbstractThe absence of phytosterol dealkylation in the cotton stainer bug, Dysdercus fasciatus, has been established and the major ecdysteroid in the fifth‐stage larvae identified. The demonstration that the free and esterified sterols in D fasciatus consisted of 95–96% sitosterol and 4–5% campesterol, a similar composition to the cottonseed diet, together with the lack of conversion of [14C]sitosterol into cholesterol, establishes that phytosterol dealkylation does not occur in this insect species. The ecdysteroid titer determined by radioimmunoassay in the fifth instar of D fasciatus shows a distinct peak at day 6, the instar lasting for 7 days. Makisterone A was purified by HPLC from insects at a time of high ecdysteroid titer and identified as a major component by both fast atom bombardment and electron impact mass spectrometry. Gas‐liquid chromatography/mass spectrometry (selected ion monitoring) confirmed the occurrence of makisterone A and revealed the presence of two unidentified compounds. One of these occurs in a similar amount to makisterone A and may be 26‐hydroxymakisterone A, whereas only a minute amount of the other compound, which may be 20‐deoxymakisterone A, was present; further identification of the latter compounds is necessary. C27 ecdysteroids (eg, ecdysone and 20‐hydroxyecdysone) and C29 ecdysteroids (eg, podecdysone A) were undetectable. The specificity of the enzymes of ecdysteroid biosynthesis is discussed.
Precocious metamorphosis and wing formation in the pea aphid, Acyrthosiphon pisum, induced by precocene analogue 7‐ethoxy‐6‐methoxy‐2,2‐dimethylchromene
Authors: Kambhampati S. , Mackauer M. , Nair K. K. 
Published: February 2005

AbstractMaternal treatment with 5 μg of the precocene analogue 7‐ethoxy‐6‐methoxy‐2,2‐dimethylchromene influenced offspring development in the pea aphid, Acyrthosiphon pisum. Under conditions favoring the production of apterous offspring, virginoparous aphids produced a significant proportion of alates and precocious adultoids; the precocious adultoids were sterile. The effect of precocene on offspring development was temporary. Some implications of precocene treatment for aphid control are discussed.
Hemolytic activities of stinging insect venoms
Authors: Schmidt Justin O. , Blum Murray S. , Overal William L. 
Published: February 2005

AbstractThe direct hemolytic activities of the venoms from 21 species of stinging insects were determined. The activities spanned 3 1/2 orders of magnitude, ranging from a low of four to a high of 12,000 hemolytic units/mg dry venom, respectively, for the solitary wasp, Dasymutilla lepeletierii, and the social wasp, Polistes infuscatus. The latter activity is the highest reported for any insect venom and represents a level that is potentially harmful to humans stung by the wasp.The social wasps as a group generally possessed highly hemolytic venoms; the ants, poorly hemolytic venoms; and the solitary stinging species, venoms with extremely low activity. For the venoms, hemolytic activity correlated with neither lethal toxicity (LD50) nor algogenicity. This finding suggests that hemolysins alone do not determine venom toxicity, and that the hemolysins of stinging insect venoms serve a variety of poorly understood roles. The range of activity of hemolysins from different venoms indicates they probably have different chemical structures and functions.
Tissue‐specificity of hemoglobin synthesis: Localization of heme synthesis in the subepidermal fat body of Chironomus thummi (Diptera)
Authors: Vafopoulou‐Mandalos Xanthe , Laufer Hans 
Published: February 2005

AbstractPossible sites of heme synthesis in the fourth instar of Chironomus thummi were investigated by means of autoradiography of specific isotope incorporation. “Body wall” preparations, which include subepidermal and visceral fat body, oenocytes, muscle, epidermis, and cuticle, were cultured for 1 h in a medium containing tritiated‐δ‐aminolevulinic acid, a specific precursor to heme biosynthesis. Light‐microscopic examination of autoradiographs of sections of the body walls indicates that the subepidermal fat body is the major site of incorporation of the precursor into heme. The visceral fat body shows few silver grains. Oenocytes, as well as muscle and epidermis, are characterized by absence of silver deposits. These findings indicate that the subepidermal fat body of Chironomus is the primary site of heme synthesis, and are discussed in relation to specific hemoglobin synthesis.
Sublethal effects of neuroactive compounds on pheromone response thresholds in male oriental fruit moths
Authors: Linn C. E. , Roelofs W. L. 
Published: February 2005

AbstractThe pheromone‐mediated flight behavior of male Oriental fruit moths in a sustained‐flight tunnel was observed after males were treated topically with sublethal concentrations of permethrin, carbaryl, chlordimeform, dieldrin, octopamine, serotonin, yohimbine, and cyproheptadine. With the exception of serotonin all compounds were found to disrupt one or more specific elements of the male precopulatory flight sequence. Among the insecticides, dieldrin was least active, whereas permethrin, carbaryl, and chlordimeform induced unique effects at specific phases of the sequence. Octopamine induced a hypersensitivity to the olfactory signal and mimicked one of the effects observed with chlordimeform. Yohimbine and cyproheptadine significantly decreased moth activation to the chemical signal but did not alter flight performance in responding moths. Yohimbine and cyproheptadine also reversed the effects induced by octopamine. The results of our study show that the complex precopulatory sequence of behaviors exhibited by males is very sensitive to sublethal concentrations of a range of neuroactive compounds.
Chemical and immunological properties of lipophorins from seven insect orders
Authors: Ryan Robert O. , Law John H. , Schmidt Justin O. 
Published: February 2005

AbstractThe major insect hemolymph lipoprotein, lipophorin, was isolated from adults of eight insect species representing seven insect orders. Sodium dodecyl sulfate polyacrylamide gel electrophoresis was used to compare their respective apoprotein components. In all species examined lipophorin was composed of at least two apoproteins, apolipophorin I (Mr ∼ 250,000) and apolipophorin II (Mr ∼ 78,000), and two species had a third apoprotein, apolipophorin III (Mr ∼ 17,000). The density of each isolated lipophorin was determined from the refractive index of KBr following density gradient centrifugation. Immunoblotting with anti‐larval Manduca sexta apolipophorin I and II of the apoproteins separated by SDS‐PACE indicated cross reactivity between anti‐M sexta apoLp‐ll and apoLp‐ll in all species tested. Anti‐M sexta apoLp‐l exhibited no cross reactivity for any species tested. Fluorescent lectin staining of the apoproteins separated on SDS‐PAGE gels revealed the presence of covalently bound carbohydrate residues.
Ecdysteroid level and the change in sensitivity to a juvenile hormone analogue in Ephestia cautella larvae (Lepidoptera, Phycitidae)
Authors: Lazarovici P. , Shapira D. , Pisarev V. , Shaaya E. 
Published: February 2005

AbstractA double‐antibody ecdysone‐specific radioimmunoassay was used to clarify whether the effects on metamorphosis of the juvenile hormone analogue methoprene are correlated with changes in ecdysteroids level. It appears that a small ecdysteroids peak, 5 days before pupation, is responsible for the transition from inhibition to defective metamorphosis. Study of the changes in ecdysteroid titer in last‐instar larvae treated with the JHA 2 days prior to the appearance of the above small ecdysteroids' peak showed an immediate reduction in ecdysteroid level, followed by cyclic, successively reduced titer for about 20 days. After this period the larvae ceased to feed and entered to a diapauselike stage which ended in the death of the larvae. A similar effect on ecdysteroid titer and developmental arrest was exhibited by JHA‐treated first‐instar larvae. The mechanism of the interactions between JHA and ecdysteroid level deserves further investigation.
The mechanism of block of glutamate synapses by dipicolinic acid
Authors: Yamamoto Daisuke , Miyamoto Takenori , Oda Masatsugu , Usui Toako , Fukami Jun‐Ichi 
Published: February 2005

AbstractThe effect of dipicolinic acid (2,6‐pyridine dicarboxylic acid) on the mealworm neuromuscular junction was studied using conventional microelectrode recording techniques. Dipicolinic acid (10−5‐10−3 M) added to the bathing solution reversibly blocked neuromuscular transmission. The depolarization in response to iontophoretically applied L‐glutamate (glutamate potential) was not affected by dipicolinic acid even when the neurally evoked excitatory postsynaptic potential (EPSP) was totally abolished. Focal extracellular recordings from single synaptic sites revealed that in the presence of 1 x 10−4 M dipicolinic acid the presynaptic spike was unchanged, but the quantal content for evoked transmitter release was reduced. The calcium‐dependent action potential elicited by direct stimulation of the muscle fiber was not impaired by dipicolinic acid. These results suggest that dipicolinic acid interferes with the transmitter‐releasing mechanism from the presynaptic terminal.