bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cyclic AMP and cyclic GMP independent stimulation of ventricular calcium current by peroxynitrite donors in guinea pig myocytes
Authors: Malan Daniela , Levi Renzo Cesare , Alloatti Giuseppe , Marcantoni Andrea , Bedendi Ivano , Gallo Maria Pia 
Published: September 2003

AbstractWe investigated the potential involvement of peroxynitrite (ONOO−) in the modulation of calcium current (ICa) in guinea pig ventricular myocytes with the whole‐cell patch clamp technique and with cyclic AMP (cAMP) measurements. Because of the short half‐life of ONOO− at physiological pH, we induced an increase in its intracellular levels by using donors of the precursors, nitric oxide (NO) and superoxide anion (O2−). High concentrations of NO donors, SpermineNONOate (sp/NO, 300 μM) or SNAP (300 μM) increased basal ICa (50.3 ± 4.6%, n = 7 and 46.2 ± 5.0%, n = 13). The superoxide anion donor Pyrogallol (100 μM) also stimulated basal ICa (44.6 ± 2.8%, n = 11). At lower concentration sp/NO (10 nM) and Pyrogallol (1 μM), although separately ineffective on ICa, enhanced the current if applied together (33.5 ± 0.7%, n = 7). The simultaneous donor of O2− and NO, SIN‐1 (500 μM), also stimulated basal ICa (22.8 ± 2.1%, n = 13). In the presence of saturating cyclic GMP (cGMP, 50 μM) in the patch pipette or of extracellular dibutyryl cGMP (dbcGMP, 100 μM), ICa was still increased by SIN‐1 (32.0 ± 6.1%, n = 4 and 30.0 ± 5.4%, n = 8). Both Manganese(III)tetrakis(4‐benzoic acid) porphyrin chloride (MnTBAP, 100 μM) a ONOO− scavenger, and superoxide dismutase (SOD) (150 U/ml) reversed the stimulatory effect of SIN‐1 on ICa (respectively −0.6 ± 4.1%, n = 4 and 3.6 ± 4.3%, n = 4). Intracellular cAMP level was unaltered by SIN‐1, while it was enhanced by blocking the NO–cGMP pathway with the NO synthase inhibitor L‐NMMA. These results suggest that peroxynitrite donors increase cardiac calcium current without the involvement of cAMP and cGMP. J. Cell. Physiol. 197: 284–296, 2003© 2003 Wiley‐Liss, Inc.
Moyamoya‐induced paroxysmal dyskinesia
Authors: Gonzalez‐Alegre Pedro , Ammache Zakaria , Davis Patricia H. , Rodnitzky Robert L. 
Published: September 2003

AbstractMoyamoya disease (MMD) is an uncommon intracranial vasculopathy that typically presents with ischemic or hemorrhagic stroke. Persistent choreoathetosis has been identified as a rare early manifestation of MMD. We present 2 patients with paroxysmal dyskinesia as the initial symptom of MMD, one resembling paroxysmal kinesigenic dyskinesia (PKD) and the other paroxysmal non‐kinesigenic dyskinesia (PNKD). We also review the cases of moyamoya‐induced chorea reported previously, none of which resembled PKD or PNKD. We hypothesize that both hormonal and ischemic factors may be implicated in the pathogenesis of these abnormal involuntary movements. These cases suggest that MMD should be included in the differential diagnosis of PKD and PNKD. © 2003 Movement Disorder Society
Sensory training as treatment for focal hand dystonia: A 1‐year follow‐up
Authors: Zeuner Kirsten E. , Hallett Mark 
Published: September 2003

AbstractIn a prior study, 10 patients with focal hand dystonia learned braille reading as sensory training for 8 weeks. Practice time was 30 to 60 minutes daily. They improved both their spatial acuity using the Grating Orientation Discrimination Task (GOT) and their dystonia using the Fahn scale. Three patients continued training for 1 year. Patients showed further improvement in the GOT, writing a standard paragraph, and self‐rating scales. Sensory training lasting longer than 8 weeks may lead to continued improvement. © 2003 Movement Disorder Society
Regional and racial differences in the prevalence of physician‐diagnosed essential tremor in the United States
Authors: Louis Elan D. , Fried Linda P. , Fitzpatrick Annette L. , Longstreth William T. , Newman Anne B. 
Published: September 2003

AbstractFor reasons that are unclear, prevalence estimates of essential tremor (ET) differ considerably across the United States. Separate communities have never been sampled within the framework of the same study to substantiate these differences. We estimated the prevalence of physician‐diagnosed ET in the elderly in four communities in the United States in whom the same screening questions were used, and examined whether this prevalence differed between Caucasians and African Americans. The Cardiovascular Health Study recruited a sample of Medicare beneficiaries ≥65 years of age from four communities in different regions of the United States. In 1998 to 1999, 3,494 participants (mean age, 80.0 years; range, 70–103 years) answered a 12‐question screen for ET, including the question, “has a doctor diagnosed you as having familial tremor or benign essential tremor?” Fifty‐four participants reported that a doctor had diagnosed them as having ET (1.5%; 95% confidence interval, [CI], 1.1–2.0%). Prevalence was similar across the four communities (1.1–2.0%). A larger proportion of Caucasians than African Americans reported a diagnosis of ET (1.7% vs. 0.4%; odds ratio = 4.9; 95% CI, 1.2–20.2; P = 0.028). In a logistic regression analysis, physician‐diagnosed ET was associated with Caucasian ethnicity (P = 0.038) but not with age, gender, education, mental status or depression scores, income, smoking status, or alcohol consumption. When a standardized screening question was used, the proportion of participants with physician‐diagnosed ET was similar across four communities, suggesting that the prevalence of this condition may be less variable than is often reported. Caucasians were five times more likely to have physician‐diagnosed ET than were African Americans. This study does not provide an explanation for this difference, which deserves further study. © 2003 Movement Disorder Society
Different effects of unilateral versus bilateral subthalamic nucleus stimulation on walking and reaching in Parkinson's disease
Authors: Bastian Amy J. , Kelly Valerie E. , Revilla Fredy J. , Perlmutter Joel S. , Mink Jonathan W. 
Published: September 2003

AbstractThe purpose of this study was to determine the effects of unilateral versus bilateral subthalamic nucleus (STN) stimulation on quantitative measures of walking and reaching in Parkinson's disease (PD). We used kinematic measures and the Unified Parkinson's Disease Rating Scale (UPDRS) motor subscale (subscale III) to evaluate the movement of 6 people with PD who had bilateral STN stimulators implanted for at least 6 months and withheld their anti‐parkinson medication for at least 8 hours. Subjects were studied with both stimulators off, one on, and both on. Kinematic data were collected as subjects walked, reached to a target, and were rated using the UPDRS motor subscale. STN stimulation improved walking speed and stride length, with the greatest benefit from bilateral stimulation. Reaching speed was improved by unilateral STN stimulation alone, with no additive effect of bilateral stimulation. UPDRS motor subscale ratings paralleled the kinematic findings. STN stimulation did not restore PD subjects' movements to the level of age‐matched controls. Overall, these results provide further evidence that the basal ganglia pathways involved in control of walking and reaching may be distinct. We speculate that basal ganglia may influence walking through bilateral pedunculopontine projections and reaching through ipsilateral thalamocortical projections. Our findings also suggest that maximal improvement of walking requires bilateral rather than unilateral STN stimulation. © 2003 Movement Disorder Society
Fast real‐time convolution algorithm for transients of nonlinearly‐terminated microwave multiport circuits
Authors: Chiang I‐Ting , Chew Weng Cho 
Published: September 2003

AbstractIn this work, a fast real‐time convolution algorithm is proposed. By using this approach, the cost for real‐time convolution in the presence of nonlinear terminations is reduced from O(N2) to O(N log2N). It is important to reduce the cost for the convolution operation because it usually dominates the computation time in a nonlinear circuit simulation. A nonlinearly‐terminated microwave 3‐port circuit, characterized by S parameters, is employed to demonstrate the efficiency of this fast algorithm. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 280–282, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11190
High‐power dual‐wavelength loop‐mirror cavity fiber laser
Authors: Abdullah F. , Mahdi M. A. , Bouzid B. , Abdullah M. K. 
Published: September 2003

AbstractA high‐power dual‐wavelength laser is constructed in two fiber‐loop mirror cavities by utilizing a common‐gain medium. The output power and side‐mode suppression ratio (SMSR) of the lasers were investigated for a bidirectionally pumped system. The outcome of the experiment shows that two lasing signals can be obtained at the wavelengths of 1546.04 and 1550.64 nm at a less than 1‐dB peak power difference, at peak powers of 7.30 and 6.57 dBm, respectively. This result was obtained without any intracavity attenuators. The side‐mode suppression ratio of both signals is around 46 dB. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 286–287, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11192
Large signal model of quantum‐well lasers for spice
Authors: Jianjun Gao , Baoxin Gao , Chunguang Liang 
Published: September 2003

AbstractA large‐signal equivalent‐circuit model of quantum‐well lasers is developed in this paper. This model is based on three‐level rate equations, including carrier transport effects and the role of the gateway state at the quantum well. The experiential formula of the optical peak gain variation with carrier density is given. Turn‐on delay and modulation frequency response of QW lasers are obtained using a SPICE simulator. The simulation results of the frequency response show excellent agreement with experimentally obtained data. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 295–298, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11195
L‐band erbium‐doped fiber ring laser with a wide tuning range
Authors: Mao Qinghe , Lit John W. Y. 
Published: September 2003

AbstractA ring erbium‐doped fiber (EDF) laser with an additional EDF saturable absorber operating in the L‐band can produce dual‐wavelength optical bistability. The bistabilities of the two wavelengths evolves in antiphase; the dual‐wavelength bistable behavior can be controlled by the cavity loss and adjusted by varying the EDF length. This property is used to switch the laser between the two wavelengths by triggering the pump source. The typical switching time is about 4–15 ms. By making use of the bistability, the laser may be tuned across the entire L‐band by using only ordinary commercial tunable fiber Bragg gratings (FBGs). An output dynamic range of 7.5 dB and an optical signal‐to‐noise ratio of 70 dB have been achieved. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 304–307, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11198
Bias‐dependence of FET intrinsic noise sources, determined with a quasi‐2D model
Authors: Lázaro A. , Maya M. C. , Pradell L. 
Published: September 2003

AbstractThe bias‐dependence of microwave‐FET intrinsic noise sources in their hybrid configuration is theoretically determined, using a new quasi‐2D (Q‐2D) physical model based on Thornber's current equation 8. It is shown that the correlation coefficient cannot be neglected, in agreement with empirical work in the literature. Experimental verification using noise‐parameter measurements up to 26 GHz is presented. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 317–319, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11202
Optical random‐bit generator employing quantum and chaotic dynamics
Authors: Ramos Rubens Viana , Giraudo Elvio César 
Published: September 2003

AbstractRandom‐bit generators, working as noise generators and producing keys for cryptography's algorithms are very useful in tests of communication links. However, a truly random sequence can be obtained only if a certain physical variable that obeys a certain statistical rule is used. In this paper we show two possible optical setups for a random‐bit generator. They are based on nonlinear quantum dynamics. Their main properties are shown analytically by using numerical simulations. We then use randomness tests to infer the quality of the bit sequences generated by the nonlinear system. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 338–342, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11208
Direct extraction technique for a small‐signal MOSFET equivalent circuit with substrate parameters
Authors: Lee Seonghearn 
Published: September 2003

AbstractA simple and efficient method to extract model parameters of a small‐signal MOSFET equivalent circuit, including substrate resistance and capacitance, is proposed. Unlike previous methods, substrate parameters, resistances, and inductances are directly determined without any curve‐fitting optimization. Good agreement between the measured and modeled S parameters is observed up to 40 GHz, thus verifying the accuracy of the model and its extraction method. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 344–347, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11210
9‐cis‐retinoic acid during in vitro maturation improves development of the bovine oocyte and increases midkine but not IGF‐I expression in cumulus‐granulosa cells
Authors: Gómez Enrique , Royo Luis‐José , Duque Paloma , Carneiro Gustavo , Hidalgo Carlos , Goyache Félix , Lorenzo Pedro L. , Alvarez Isabel , Facal Nieves , Díez Carmen 
Published: September 2003

AbstractThe isomer 9‐cis of retinoic acid (9‐cis‐RA) exerts a beneficial effect on bovine in vitro development when added to in vitro maturation (IVM) culture. In the present work, 9‐cis‐RA 5 nM was found to be stimulatory as opposed to 500 nM (toxic). Cumulus–oocyte complexes (COCs) were treated with the found physiological dose 9‐cis‐RA 5 nM, and the next determinations performed: (1) relative expression of midkine (MK) and IGF‐I, by reverse transcriptase‐polymerase chain reaction (RT‐PCR), in cumulus‐granulosa cells detached from oocytes; (2) cytoplasmic granular migration, by labeling of oocytes with fluoroscein isothiocyanate lectins; and (3) in vitro survival of blastocysts after vitrification and warming. Gene expression of MK was enhanced by 9‐cis‐RA, but not by 1% ethanol (vehicle). However, we did not detect IGF‐I expression, both in dependence on or in the absence of 9‐cis‐RA acting on cumulus‐granulosa cells. The ability of vitrified blastocysts to survive in vitro was not improved by 9‐cis‐RA. Nevertheless, since only blastocysts obtained from oocytes matured with serum survived, more factors should be considered when evaluating cryopreservation survival. The complete granular migration observed in oocytes matured with 9‐cis‐RA anticipates the gain in developmental competence of the oocyte, being MK probably involved in this beneficial effect. Mol. Reprod. Dev. 66: 247–255, 2003. © 2003 Wiley‐Liss, Inc.
Role of substrate on larval development of the freshwater teleost Pelvicachromis pulcher
Authors: Maradonna Francesca , Bavestrello Giorgio , Cardinali Marco , Olivotto Ike , Cerrano Carlo , Giovine Marco , Carnevali Oliana 
Published: September 2003

AbstractIt is known that, in an aquatic environment, the mineralogical composition of the substrate can affect the structure of settled communities. In marine environments, the presence of quartz negatively influences the formation of biofilm, as well as the selection and the colonization of the substrate by benthic organisms. Direct laboratory observation revealed that the freshwater teleost Pelivicachromis pulcher selects, when available, nonquartzitic brooding substrate. To monitor the effects of substrate on larvae development, ten lots of embryos were distributed in grid nurseries; carbonatic gravel was laid in five of the nurseries, while freshly fractured quartz gravel was used in the remaining ones. All the embryos laid in the two nurseries hatched, and 90% of the carbonate developing larvae reached adulthood, while 100% of those reared on quartz grain died 120 hr post hatching. Examination was made, both in larvae developed on carbonatic substrates and in those developed on quartz substrates, of the expression of the fetal growth factor, the insulin growth factor‐II (IGF‐II), of the molecular chaperone, the heat shock protein 70 (HSP70), which is involved in the folding of the nascent polypeptide chain, of the key enzyme of the glycolytic pathway, the glyceraldehyde‐3‐phosphate dehydrogenase (GADPH), and of the housekeeping gene, the β‐actin. All the data were normalized against 18S RNA expression. In larvae reared on quartz substrate, the genes IGF‐II and the β‐actin showed a lower expression, while the GADPH was totally suppressed and the expression of HSP70 increased. In conclusion, the data presented in this article demonstrated, for the first time, that the presence of quarzitic substrates is sufficient to stop larvae development through the inhibition of gene transcription in this African cichlid, leading to its death. Mol. Reprod. Dev. 66: 256–263, 2003. © 2003 Wiley‐Liss, Inc.
Epidermal growth factor induces Bcl‐xL gene expression and reduces apoptosis in porcine parthenotes developing in vitro
Authors: Cui Xiang‐Shun , Kim Nam‐Hyung 
Published: September 2003

AbstractThe aim of this study was to determine the interactive effects of bovine serum albumin (BSA) and epidermal growth factor (EGF) on the viability and development of porcine presumptive diploid parthenotes developing in vitro. The addition of 0.1 and 0.4% BSA to the culture medium enhanced the development of 4‐cell parthenotes to the blastocyst stage but EGF had no effect. However, while BSA also increased cell numbers, it did so only when EGF was also present. Either agent on its own had no effect. Similarly, apoptosis in the blastocysts was not influenced by either agent on its own but was reduced when both BSA and EGF were present. Furthermore, semi‐quantitative reverse transcriptase‐polymerase chain reaction (RT‐PCR) revealed that EGF enhanced the mRNA expression of Bcl‐xL in the presence of 0.4% BSA but BSA and EGF alone had no effect. EGF and/or BSA did not influence Bak gene expression in the blastocyst stage parthenotes. These results suggest that EGF and BSA synergistically enhance Bcl‐xL gene expression, which may result in a net increase in cell number in porcine presumptive diploid parthenotes developing in vitro. Mol. Reprod. Dev. 66: 273–278, 2003. © 2003 Wiley‐Liss, Inc.
Quantitative determination of anti‐fungal and insecticide amides in adult plants, plantlets and callus from Piper tuberculatum by reverse‐phase high‐performance liquid chromatography
Authors: Debonsi Navickiene Hosana M. , Bolzani Vanderlan da S. , Kato Massuo J. , Pereira Ana Maria S. , Bertoni Bianca Waléria , França Suzelei Castro , Furlan Maysa 
Published: September 2003

AbstractA rapid, sensitive and reliable reverse‐phase HPLC method was used for the quantitative determination of the anti‐fungal and insecticide amides, dihydropiplartine (1), piplartine (2), Δα,β‐dihydropiperine (3) and pellitorine (4) in plants in natura, in plantlets in vitro and ex vitro, and in callus of Piper tuberculatum. Well‐resolved peaks were obtained with good detection response and linearity in the range of 15.0–3000 µg/mL. The plants in natura contained compounds 1–4, the plantlets ex vitro and in vitro accumulated compounds 1–2 and 1–4, respectively, while only amide 4 was found in callus. Copyright © 2003 John Wiley & Sons, Ltd.
The risk of liver disorders in women prescribed cyproterone acetate in combination with ethinyloestradiol (Dianette): a nested case‐control study using the GPRD
Authors: Seaman H. E. , de Vries C. S. , Farmer R. D. T. 
Published: September 2003

AbstractPurposeTo explore the risk of liver disorders associated with cyproterone acetate combined with ethinyloestradiol (CPA/EE). CPA/EE is licensed in the UK for the treatment of women with acne and hirsutism and is a treatment option for polycystic ovary syndrome (PCOS). It acts as a contraceptive also.MethodsUsing the General Practice Research Database, we conducted a cohort analysis and case‐control study in women aged 15–39 with acne, hirsutism or PCOS to estimate the risk of liver disorders associated with CPA/EE.ResultsCompared with cases exposed to conventional combined oral contraceptives (COCs), the age‐adjusted incidence rate ratio for liver disorders in women using CPA/EE was 1.7 (95%CI: 0.9,3.4) and compared with no use it was 1.5 (95%CI: 0.8, 2.8). In the case‐control study, the adjusted odds ratio (OR) for liver disorders in women exposed to CPA/EE was 1.6 (95%CI: 0.7, 3.5) and 0.8 (95%CI: 0.5, 1.3) for exposure to conventional COCs, compared with no use. The risk of liver disorders in women prescribed CPA/EE was not significantly greater than that in women prescribed conventional COCs (OR: 2.1 [95%CI: 0.9, 4.8]).ConclusionOur results do not indicate an increased risk for liver disorders associated with CPA/EE use in women with acne, hirsutism or PCOS after adjusting for potential confounding. This may be due to lack of statistical power. Copyright © 2003 John Wiley & Sons, Ltd.
Hemicyanine n‐butyltriphenylborate salts as effective initiators of free‐radical polymerization photoinitiated via photoinduced electron‐transfer process
Authors: Kabatc Janina , Jędrzejewska Beata , Pączkowski Jerzy 
Published: September 2003

AbstractTwo different groups of hemicyanine n‐butyltriphenylborate salts (HCBo) were synthesized and examined to verify the possibility of the Marcus equation application for the description of the kinetics of free‐radical polymerization photoinitiated via the photoinduced electron‐transfer process. The free‐energy change (ΔGel) of the electron‐transfer process between an excited acceptor and a donor were experimentally determined for 14 new organic photoredox pairs. The relationship between the rate of polymerization and the free‐energy change for the electron‐transfer process displayed typical Marcus kinetic behavior. The photoreduction of the HCBo produced colorless products. The experimental results indicated that the rate of the light‐absorber bleaching process does not compete with the photoinitiation of polymerization. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3017–3026, 2003
Self‐organized liquid‐crystalline polyethers obtained by grafting tapered mesogenic groups onto poly(epichlorohydrin): Toward biomimetic ion channels
Authors: Ronda Joan Carles , Reina José Antonio , Cádiz Virginia , Giamberini Marta , Nicolais Luigi 
Published: September 2003

AbstractA set of high‐molecular‐weight new side‐chain liquid‐crystalline polyethers was obtained by chemical modification of poly(epichlorohydrin) with potassium 3,4,5‐tris(dodecyloxy)benzoate. The degree of modification ranged from 48 to 70% depending on the reaction conditions, and the upper value was an apparent modification plateau. NMR characterization indicated that no side reactions of any kind occurred (e.g., deshydrohalogenation). All copolymers had a nematic columnar mesophase whose range of stability depended on the modification degree. X‐ray diffraction experiments performed on mechanically oriented samples showed that tapered groups were tilted with respect to the column axes. Also X‐ray experiments and density measurements demonstrated that the number of disks per unit cell decreased as the modification degree increased. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2918–2929, 2003