bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fast pH‐thermo‐responsive copolymer hydrogels with micro‐porous structures
Authors: Kishi R. , Miura T. , Kihara H. , Asano T. , Shibata M. , Yosomiya R. 
Published: April 2003

AbstractMicro‐porous copolymer hydrogels were prepared by γ‐ray irradiation of mixed solutions of N‐isopropylacrylamide (NIPAAm) and acrylic acid (AAc) above the lower critical solution temperature (LCST). From Cryo‐SEM observations, the gels were found to consist of three‐dimensional fibrous micro‐gels and micro‐pores. The copolymer gels swelled at temperatures below the LCST and shrunk at temperatures above it, and they showed rapid volume transitions on a time scale on the order of a minute when experiencing temperature changes between 10 and 40°C. The transition times for thermal shrinking were almost the same regardless of AAc composition, but the transition times for thermal swelling were increased with increasing AAc contents. The copolymer gels also showed rapid volume transitions with time constants on the order of an hour on experiencing pH changes between 2 and 12. The transition times for pH volume change at 10°C were within one hour, except for the gels containing only small amounts of AAc. On the other hand, the transition times for pH‐dependent volume change at 40°C were increased with increasing AAc content. The lower responsiveness of the transition results from an increase in hydrophobicity arising from the formation of inter‐ and intra‐molecular hydrogen bonds between the non‐ionized carboxylic acid groups and the amide groups. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 75–84, 2003
Synthesis and properties of graft copolymer of cellulose diacetate with poly(caprolactone monoacrylate)
Authors: Wang Dongshan , Xuan Yingnan , Huang Yong , Shen Jiarui 
Published: April 2003

AbstractCellulose diacetate grafting poly(caprolactone monoacrylate) copolymers (CDA‐g‐PCLA) were synthesized by a two‐step reaction of cellulose diacetate (CDA) with poly(caprolactone monoacrylate) (PCLA). The isocyanate‐terminated intermediate (NCOPCLA) was prepared and grafted onto cellulose diacetate chains. The results of the structure analysis indicated that PCLA was connected to CDA by chemical bonding. The flow temperature of graft copolymers was lower than that of the pure CDA and decreased with increasing the grafting percentage. Outdoor soil burial tests and active sludge tests indicated that the graft copolymers have good biodegradability in natural conditions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 85–90, 2003
Genomics and mapping of Teleostei (bony fish)
Authors: Clark Melody S. 
Published: April 2003

AbstractUntil recently, the Human Genome Project held centre stage in the press releases concerning sequencing programmes. However, in October 2001, it was announced that the Japanese puffer fish (Takifugu rubripes, Fugu) was the second vertebrate organism to be sequenced to draft quality. Briefly, the spotlight was on fish genomes. There are currently two other fish species undergoing intensive sequencing, the green spotted puffer fish (Tetraodon nigroviridis) and the zebrafish (Danio rerio). But this trio are, in many ways, atypical representations of the current state of fish genomic research. The aim of this brief review is to demonstrate the complexity of fish as a group of vertebrates and to publicize the ‘lesser‐known’ species, all of which have something to offer. Copyright © 2003 John Wiley & Sons, Ltd.
Determinants of the exclusion zone in dopaminergic amacrine cell mosaics
Authors: Raven Mary A. , Eglen Stephen J. , Ohab John J. , Reese Benjamin E. 
Published: April 2003

AbstractA fundamental organizing feature of the retina is the presence of regularly spaced distributions of neurons, yet we have little knowledge of how this patterning emerges during development. Among these retinal mosaics, the spatial organization of the dopaminergic amacrine cells is unique: using nearest‐neighbor and Vornoi domain analysis, we found that the dopaminergic amacrine cells were neither randomly distributed, nor did they achieve the regularity documented for other retinal cell types. Autocorrelation analysis revealed the presence of an exclusion zone surrounding individual dopaminergic amacrine cells and modeling studies confirmed this organization, as the mosaic could be simulated by a minimal distance spacing rule defined by a broad set of parameters. Experimental studies determined the relative contributions of tangential dispersion, fate determination, and cell death in the establishment of this exclusion zone. Clonal boundary analysis and simulations of proximity‐driven movement discount tangential dispersion, while data from bcl‐2 overexpressing mice rule out feedback‐inhibitory fate‐deterministic accounts. Cell death, by contrast, appears to eliminate dopaminergic amacrine cells that are within close proximity, thereby establishing the exclusion zone surrounding individual cells and in turn creating their mosaic regularity. J. Comp. Neurol. 461:123–136, 2003. © 2003 Wiley‐Liss, Inc.
Cervicovaginal (Papanicolaou) smear findings in patients with malignant mixed Müllerian tumors
Authors: Casey Mary B. , Caudill Jill L. , Salomão Diva R. 
Published: April 2003

AbstractMalignant mixed Müllerian tumor is a rare neoplasm that occurs most frequently in elderly patients. It is characterized by a mixture of malignant epithelial and sarcomatous components. Little has been published about Papanicolaou smear findings pertaining to malignant mixed Müllerian tumors. We present our experience, with an emphasis on cytologic detail. Nine patients (median age, 65 yr) met our study criteria. All available smears and surgical specimens were reviewed. Four smears were positive for malignancy, with a sensitivity of 44% (3 adenocarcinoma, and 1 squamous‐cell carcinoma, small‐cell type). The results of our study showed that Papanicolaou smear findings pertaining to malignant mixed Müllerian tumors are seen in patients with advanced‐stage disease with involvement of the lower uterine segment or cervix. The usual finding is large numbers of high‐grade epithelial malignant cells in a necrotic background. The mesenchymal component rarely sheds cells visible on Papanicolaou smear. Diagn. Cytopathol. 2003;28:245–249. © 2003 Wiley‐Liss, Inc.
Synthesis of 3‐substituted pyrido[4′,3′:4,5]thieno[2,3‐d]pyrimidines and related fused thiazolo derivatives
Authors: Ahmed Essam Kh. 
Published: April 2003

AbstractConvenient syntheses of 3‐substituted ethyl 4‐oxo‐2‐thioxo‐1,2,3,4,5,6,7,8‐octahydropyrid[4′,3′:4,5]thieno[2,3‐d]pyrimidine‐7‐carboxylates 3a, b, 6, 11–13, ethyl 3‐methyl‐5‐oxo‐2,3,6,9‐tetrahydro‐5 H‐pyrido[4′,3′:4,5]thieno[2,3‐d][1,3]thiazolo[3,2‐a]pyrimidine‐8‐7H‐carboxylate (4), and ethyl 2‐methyl‐5‐oxo‐2,3,6,9‐tetrahydro‐5H‐pyrido[4′,3′:4,5]thieno[2, 3‐d][1,3]thiazolo[3,2‐a]pyrimidine‐8[7H]carboxylate (8) from diethyl 2‐isothiocyanato‐4,5,6,7‐tetrahythieno[2,3‐c]pyridine‐3,6‐dicarboxylate (1) are reported. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:201–207, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10131
Impairment of individual finger movements in Parkinson's disease
Authors: Agostino Rocco , Currà Antonio , Giovannelli Morena , Modugno Nicola , Manfredi Mario , Berardelli Alfredo 
Published: April 2003

AbstractBy analyzing the kinematics of repetitive, constant‐amplitude, finger oppositions, we compared the impairment of individual and nonindividual finger movements in patients with Parkinson's disease. In one task, subjects tapped only the index finger against the thumb (individual oppositions); in the other task, they tapped all four fingers together against the thumb pad (nonindividual oppositions). We used an optoelectronic motion analysis system to record movements in three‐dimensional space and recorded three 5‐second trials for each task. We counted how many finger oppositions subjects performed during each trial and measured the duration and amplitude of the flexions and extensions. We also calculated the duration of the pauses after flexion and extension. We assessed the deterioration of motor performance in patients by investigating the changes in speed and amplitude with task completion. During both tasks, normal subjects and patients performed finger flexions faster than extensions, and they invariably paused longer after flexion than after extension. Patients performed individual and nonindividual finger movements slowly and with reduced amplitude. Patients were disproportionately slow during flexion and in switching from flexion to extension. Movement slowness increased as finger oppositions progressed but predominantly when patients had to move fingers individually. In conclusion, in patients with Parkinson's disease, the motor performance deteriorated with task completion more during individual than during nonindividual finger movements. Parkinson's disease, therefore, impairs individual finger movements more than gross hand movements. This distinction reflects the finer cortical control needed to promote and sustain this highly fractionated type of motor output. © 2003 Movement Disorder Society
Mirtazapine in essential tremor: A double‐blind, placebo‐controlled pilot study
Authors: Pahwa Rajesh , Lyons Kelly E. 
Published: April 2003

AbstractWe sought to determine whether mirtazapine is safe and well‐tolerated as a treatment for essential tremor (ET). We studied mirtazapine in a randomized, double‐blind, placebo‐controlled, crossover study of 17 ET patients. Patients were started with 15 mg per day of either mirtazapine or placebo for 1 week and the dose was escalated weekly until the targeted dose of 45 mg per day was achieved. This dose was maintained for 2 weeks. Tremor was assessed at baseline and after 14 days of 45 mg of mirtazapine or placebo. There was a minimum washout period of 14 days between the two arms of the study. Tremor assessments included global improvement, Fahn Tolosa Marin Tremor Rating Scale, Beck Depression Inventory and the Parkinson's Disease Questionnaire‐39. Patient global improvement ratings indicated that in the placebo condition 12 patients were unchanged and 1 patient was mildly improved. In the mirtazapine condition, 10 patients were unchanged, 2 were moderately improved and 1 was markedly improved. There was no significant improvement with mirtazapine or placebo compared to baseline as measured by the Tremor Rating Scale. Adverse effects were more common in the mirtazapine group and included drowsiness, confusion, dry mouth, weight gain, polyuria, itching, nausea, gait and balance problems, blurred vision, and bad taste. We conclude that the majority of the ET patients do not benefit from mirtazapine. Mirtazapine has significant adverse effects and should be used cautiously in ET patients. © 2003 Movement Disorder Society
Short‐term effect of a single levodopa dose on micturition disturbance in Parkinson's disease patients with the wearing‐off phenomenon
Authors: Uchiyama Tomoyuki , Sakakibara Ryuji , Hattori Takamichi , Yamanishi Tomonori 
Published: April 2003

AbstractWe investigated the short‐term effects of a single dose of levodopa (L‐dopa) on micturition function in PD patients with wearing‐off phenomenon. Eighteen PD patients who had median Hoehn and Yahr scores of 5 during the off phase and 3 during the on phase were recruited. We carried out urodynamic studies before and about 1 hour after the patients had taken 100 mg of L‐dopa with dopa‐decarboxylase inhibitor (DCI). After taking the L‐dopa/DCI, urinary urgency and urge incontinence aggravated, whereas voiding difficulty was alleviated in all 12 patients. When compared to the baseline assessment, urodynamic study results after taking 100 mg of L‐dopa/DCI showed aggravated detrusor hyperreflexia; decreased maximum bladder capacity (P = 0.006); an increased maximum Watts Factor value (P = 0.001), reflecting the detrusor power on voiding; an increased Abrams‐Griffiths number (P = 0.042), reflecting urethral obstruction on voiding; decreased residual urine volume (P = 0.025); and increased static urethral closure pressure (P = 0.012). One hundred milligrams of L‐dopa/DCI worsened detrusor hyperreflexia, producing worsened urinary urgency and urge incontinence during the storage (bladder‐filling) phase. It also increased detrusor contractility much more than it did urethral obstruction in the voiding phase, producing overall lessening of voiding difficulty and improving voiding efficiency in our PD patients with the wearing‐off phenomenon. © 2003 Movement Disorder Society
Protective effect of Spirulina on lead induced deleterious changes in the lipid peroxidation and endogenous antioxidants in rats
Authors: Upasani C. D. , Balaraman R. 
Published: April 2003

AbstractThe present study aims to investigate the protective effect of Spirulina on lead‐induced changes in the levels of lipid peroxidation and endogenous antioxidants in liver, lung, heart, kidney and brain of rats. Levels of elemental lead were also measured in the organs of rats in all experimental groups. In the liver, lung, heart and kidney of lead‐exposed animals, there was a signiﬁcant (p < 0.001) increase in the lipid peroxidation and a decrease in the levels of endogenous antioxidants. Although, Spirulina did not affect the deposition of lead in organs apart from the brain, simultaneous administration of Spirulina to lead exposed animals signiﬁcantly (p < 0.001) inhibited lipid peroxidation and restored the levels of endogenous antioxidants to normal.To conclude, Spirulina had a signiﬁcant effect on scavenging free radicals, thereby protecting the organs from damage caused by the exposure to lead. Further more, Spirulina showed a signiﬁcant (p < 0.05) decrease in the deposition of lead in the brain. Copyright © 2003 John Wiley & Sons, Ltd.
The Gts1 protein stabilizes the autonomous oscillator in yeast
Authors: Adams Claire A. , Kuriyama Hiroshi , Lloyd David , Murray Douglas B. 
Published: April 2003

AbstractContinuous cultures of Saccharomyces cerevisiae show a robust autonomous temperature compensated oscillation in many metabolic functions. Respiratory activity, a convenient output to measure, oscillates with a period of 40 min. Deletion of GTS1, whose protein product has homology to the circadian per protein, has been implicated in temporal events within yeast, causes a reduction in periodicity to 18 min (wild‐type period 40–60 min). The dilution rate was steadily increased from 0.04/h to 0.085/h and the oscillation stabilized after four to six dilutions. However, Gts1p's involvement in the maintenance and generation of metabolic synchrony, and in the central oscillating loop, appear to be minimal, as the mutant oscillation was robust and autonomous. Deletion of GTS1 did cause decreased temperature compensation of the period of the oscillation from Q10 = 1.07 for the wild‐type to Q10 = 1.6 for the mutant. Also the degree of nutrient compensation observed for the wild‐type was not observed in the GTS1‐null mutant strain. It is postulated that Gts1p is involved in the mechanism that communicates external conditions, such as temperature, to the central oscillating loop. Copyright © 2003 John Wiley & Sons, Ltd.
Localization of desmin in cultured astrocytes and its distribution in relation to glial fibrillary acidic (GFA) protein
Authors: Raju T. R. , Dahl D. 
Published: April 2003

AbstractIn dissociated cultures from newborn rat brain, it is shown that astrocytes which are positive with GFA antisera also stain with desmin antisera. However, the localization of these two proteins within the same cell seems to be different as revealed by double immunofluorescence employing both these antisera.
The adrenocortical response to stress from the pre‐hatching period to the adult state in the pigeon: Thalamic participation
Authors: Ramade Fred , Baylé Jean‐Dominique 
Published: April 2003

AbstractThe stress‐induced adrenocortical response was kinetically evaluated for 100 min after ether vapor exposure in late embryos (30 h before hatching) and in 1, 2, 3 and 6‐wk‐old squabs. An‐adult‐pattern of corticosterone profile was seen in intact 6‐wk‐old pigeons, i.e. a polyphasic increase of corticosterone including successive peaks at 12–15, 35, 60 and 90 min after stress application. In 1‐wk‐old squabs, a small adrenocortical response to stress included only a single peak of corticosterone at 12–15 min. The early peak was found again, with the same magnitude, 2 wk after hatching but it was followed by two later and smaller peaks 35 and 60 min after stress. The adult pattern was visible in 3‐wk‐old stressed pigeons, although the magnitude of the response was still smaller than in adult controls. A single, high peak of corticosterone occurred 12–15 min after stress application, without any later peak, in embryos and a similar monophasic response was seen in thalamic lesioned adult birds. Therefore, it can be suggested that the polyphasic reverberating adrenocortical response to stress depends upon relationships between the adrenocorticotrophic hypothalamus and the anterior mediodorsal thalamus. Such thalamic‐hypothalamic interrelations appear to mature during the early post‐hatching weeks.
Lipid composition of gray and white matter in developing rat brain
Authors: Reddy T. Sanjeeva , Rajalakshmi R. , Ramakrishnan C. V. 
Published: April 2003

AbstractThe lipid composition of gray and white matter was studied in the developing rat brain. For this purpose, gray and white matter were separated from the brains of rats from different age groups and were used for the estimation of moisture and lipids. The moisture content of both gray and white matter decreased with age, but the decrease was more significant in the latter. The concentration of different lipids in gray matter reached adult values at 4 weeks of age, whereas the lipids in white matter showed a slower increase even after this period. Similarly, the content of gray matter reached adult values much earlier (by 3 weeks) than white matter, which continued to increase throughout the period of study. Myelin represented 40% of the dry weight of whitematter. The non‐myelin portion of white matter had a different lipid composition than gray matter, white matter, or myelin.
Some electrophysiological properties of developing rat skeletal myotubes grown in serum‐free, chemically defined medium
Authors: Yoles Esther , Bak Asia , Sampson S.R. 
Published: April 2003

AbstractSerum‐free, chemically defined media have been reported to provide suitable conditions for growth and proliferation of mammalian skeletal muscle, but there is no information regarding the ability of myotubes to develop normal electrophysiological properties in these media. We have recorded transmembrane resting and action potentials from rat skeletal myotubes grown in both serum‐containing (GM) and serum‐free chemically defined (CDM) growth media. Muscle cells in CDM do not develop as high resting Em as their counterparts in conventional growth media. CDM myotubes also had a lower incidence and frequency of spontaneously occurring action potentials. Treatment with ouabain or decrease in temperature of the recording medium reduced resting Em of both GM and CDM cells to the same level. We found that the sensitivity of CDM cells to ouabain was about 10‐fold higher than that of GM cells. An increase in temperature of the recording medium increased Em of GM myotubes but not of CDM myotubes. The change in resting Em in response to a 10‐fold change in extracellular K+‐ion concentration was the same for both groups of cells thus indicating that there was no difference in membrane permeability to K+‐ion. We conclude that the difference in Em can be accounted for largely, if not entirely, by differences in activity or amount of electrogenic Na+‐K+ ATPase.
Ontogeny of glutamine synthetase in rat brain
Authors: Chatterjee D. , Sarkar P. K. 
Published: April 2003

AbstractThe developmental pattern of glutamine synthetase (GS) in rat brain has been studied with respect to that of the cells involved in the synthesis of the enzyme. GS activity is very low until day 13 after birth, rises sharply between days 13 and 15, and slowly thereafter. In contrast, more than half of the total number of protoplasmic astrocytes—the cells involved in synthesis of GS—are formed by day 12, following which the rate of proliferation declines considerably. GS is precociously inducible by cortisol in purified protoplasmic astrocytes, in organ cultures of 6–13 day rat brain and in the brains of cortisoladministered 12 day rats. These results and the temporal coincidence of the period of increase of GS with the onset of the function of adrenal cortex suggest that GS activity in the developing rat brain is under steroidal control.
Chemically defined medium for rat astroglial cells in primary culture
Authors: Weibel M. , Pettmann B. , Daune G. , Labourdette G. , Sensenbrenner M. 
Published: April 2003

AbstractWe have developed a serum‐free defined medium that supports the growth in primary culture of rat astroglial cells. Cells dissociated from cerebral hemispheres of newborn rats were maintained for 4 days in a basal medium (Waymouth's medium) containing 10% fetal calf serum, which was substituted by a serum‐free medium. The basal medium was supplemented with insulin (5 μg/ml) and fatty acid free bovine serum albumin (0.5 mg/ml). Under these conditions the cells proliferate as estimated by cell counts and DNA content; however, growth was less than in Waymouth's medium supplemented with 10% fetal calf serum. In contrast, a very similar morphology was observed between cultures grown in the serum‐free or serum‐containing media. The serum‐free medium allows some maturation of the astroglial cells as shown by the presence of glial fibrillary acidic (GFA) protein, S‐100 protein and glutamine synthetase (GS) activity. The astroglial cells can survive and grow in this chemically defined medium for up to 5 weeks. The ability to culture astroglial cells in such a minimal defined medium should facilitate investigations concerning the effects of growth factors on their proliferation and maturation.
Long term reduction in eight arm maze performance after early exposure to phenobarbital
Authors: Pick Chaim G. , Yanai Joseph 
Published: April 2003

AbstractPerformance in the hippocampal eight arm maze was studied in mice after early exposure to phenobarbital (PhB). since previous studies suggested that these animals suffered neural deficits in the hippocampus. For prenatal exposure pregnant mothers were fed 3 g PhB/kg milled food on gestation days 9–18. Neonates were injected daily with 50 mg PhB/kg. on postnatal days 2–21. After a week of water deprivation, the animals were tested at age 50 days for 5 days preceded by 1 day of habituation. Deficits in eight arm maze performance were demonstrated in early treated mice on every testing day. For example, on day 5 of testing the number of correct entries during the first eight attempts in the prenatally treated group were 12% below control level (P<0.01), the respective reduction in the neonatal group was 10% (P< 0.001). The number of trials needed to enter all arms on day 5 was 27% above control level among prenatally treated mice (P< 0.001), and 13% in neonatally treated mice (P< 0.05). It took prenatal PhB animals twice the time to reach criterion than their controls (P< 0.001) and four times as long for neonatally treated mice (P< 0.001).