bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Modifid Jebsen Test of Hand Function and the University of Maryland Arm Questionnaire for Stroke
Authors: Bovend'Eerdt T JH , Dawes H , Johansen-Berg H , Wade D T
Published: March 2004

Objective: To examine the concurrent validity and test–retest reliability of the Modified Jebsen Test of Hand Function (MJT) and the University of Maryland Arm Questionnaire for Stroke (UMAQS).

Design: Individuals with acquired neurological disorders were retested within an average of 9.6 days after the first assessment.

Setting: Individuals were recruited from two specialist rehabilitation units, members of the Multiple Sclerosis Society and Headway Group.

Subjects: Twenty-six individuals with acquired neurological disorders; stroke (12), MS (7), head injury (4), tumour (3) with moderate to high functioning upper limbs were recruited for this study.

Main outcome measures: Arm function was assessed using the MJT, the UMAQS, the Nine Hole Peg Test (NHPT) and grip strength, calculating the ratio between affected and unaffected arm.

Results: The MJT showed good concurrent validity. Pearson's correlation with the NHPT was 0.86 and 0.88, on T1 and T2 respectively. The UMAQS showed no significant correlation with grip strength, the NHPT and the MJT. Test–retest reliability of the MJT was high with a correlation of 0.95, and 95% limits of agreement of 0.02 ± 0.14. Correlations over time of the dominant hand/nondominant hand of the UMAQS were 0.72 and 0.83, with limits of agreement of -2.92 ± 13.28 and 1.73 ± 11.53.

Conclusions: The present study supports the use of the MJT as a measure of gross functional dexterity. More information is needed to evaluate the UMAQS.
Instruments for assessing the burden of informal caregiving for stroke patients in clinical practice: a comparison of CSI, CRA, SCQ and self-rated burden
Authors: van Exel N Job A , op Reimer Wilma JM Scholte , Brouwer Werner BF , van den Berg Bernard , Koopmanschap Marc A , van den Bos Geertrudis AM
Published: March 2004

Objective: To compare the feasibility, convergent and clinical validity of three commonly used burden scales: Caregiver Strain Index (CSI), Caregiver Reaction Assessment (CRA) and Sense of Competence Questionnaire (SCQ), with a self-developed single question on self-rated burden (SRB).

Subjects: Stroke patients receiving support from an informal caregiver ( n=148) and their caregivers were followed up to six months after stroke.

Intervention: Feasibility was assessed with several measures of missing values. Convergent validity was assessed on the basis of the correlation patterns between the burden scales, and clinical validity through evaluation of expected associations between levels of burden and explanatory patients' and caregivers' characteristics.

Results: Missing values were less often observed on CSI and SRB than SCQ and CRA. Significant correlation coefficients ( p<0.05) could be demonstrated between all burden scales, except for one subscale of CRA. Evidence for clinical validity was strongest for CSI and SRB, based on associations between higher burden scores and patients' disability, and patients' and caregivers' poor level of health-related quality of life (all p<0.05).

Conclusions: A concise and simple measure would facilitate early detection of caregivers at risk in clinical practice and research. CSI and SRB are more feasible and at least as valid instruments for assessment of caregiver burden in stroke than the longer and more complex SCQ and CRA. SRB could be used for quick screening of caregivers at risk. CSI is indicated for further diagnosis of the burden of informal caregivers.
Rlative shoulder fexor and handgrip strength is related to upper limb function after stroke
Authors: Mercierand Catherine , Bourbonnais Daniel
Published: March 2004

Objective: To compare the relative strength of different muscle groups of the paretic upper limb and assess the relationship with motor performance.

Design: Descriptive study.

Setting: Secondary care rehabilitation centre.

Subjects: A convenience sample of 13 chronic hemiparetic stroke subjects.

Main outcome measures: The maximal active torques of fivemuscle groups were measured in both upper limbs (UL) and converted into relative strength (paretic/nonparetic). The UL function was assessed using the Box and Block Test, the Finger-to-Nose Test, the Fugl-Meyer Test and the TEMPA (Test Evaluant les Membres supérieurs des Personnes Agées).

Results: The Friedman two-way analysis of variance shows a significant difference across the relative strength of the different muscle groups ( p = 0.017), but subsequent multiple comparisons indicate a significant difference between handgrip and elbow extension only (relative strength of 0.52 ± 0.27 and 0.73 ± 0.23 respectively). However, data show the presence of large intra-subject imbalances between muscle groups. The relative forces for shoulder flexion and handgrip are the best predictors of the UL function, the higher Spearman's rho correlation coefficients for each clinical test ranging from 0.70 to 0.81.

Conclusions: These results do not confirm classical clinical teaching regarding the distribution of weakness following stroke (e.g., proximal to distal gradient; extensors more affected than flexors) but support the hypothesis that strength is related to the function of the paretic upper limb.
Reliability of measurement of tempo-spatial parameters of gait after stroke using GaitMat II
Authors: Pomeroy V M , Chambers S H , Giakas G , Bland M
Published: March 2004

Objective: (1) To find the inter-rater and intra-rater reliability of raters using GaitMat II to measure tempo-spatial gait parameters of stroke patients. (2) To find if reliability is related to abnormality of footprint patterns.

Design: A prospective agreement study.

Setting: A movement analysis laboratory.

Subjects: Nineteen adults who were at least six months after stroke and able to walk 4 metres with or without assistance participated as subjects in this study. There were five raters.

Methods: Subjects completed at least two walks along GaitMat II. The raw footprint data were analysed independently by each of the five raters.

Results: Mean intraclass correlation coefficients (ICCs) for each rater within subject ranged from 0.8398 to 0.9318. However eight of the 17 parameters tested showed significant differences between raters ( p = 0.0029 to p<0.0001). When the most inexperienced rater was excluded, differences between experienced raters ( n = 4) was found to be statistically insignificant for all parameters. The association of the mean score and standard deviation of experienced raters was significant for nine parameters ( r values 0.5087 to0.9459), i.e., as walking pattern became more abnormal, variation in scoring between raters increased.

Conclusions: GaitMat II may have acceptable inter-rater reliability if raters have experience of gait analysis but disagreement may increase when stroke patients exhibit more abnormal gait patterns.
Vascular permeability alterations induced by arsenic
Authors: Chen Shih-Chieh , Tsai Ming-Hsien , Wang Hsiu-Jen , Yu Hsin-Su , Chang Louis W
Published: March 2004

The impact of arsenic on the integrity of blood vessels in vivo via in situ exposure (local injection) of arsenic was investigated. Vascular permeability changes were evaluated by means of the Evans blue assay and the India ink tracer techniques. Rats were intravenously injected with Evans blue followed by intradermal injections of various doses of sodium arsenite on the back skins of the animals. Evans blue at different time points was extracted and assayed as indices of vascular leakage. Skin at various time point injection sites was sampled for arsenic measurement via graphite furnace atomic absorption spectroscopy. Our time course study with Evans blue technique demonstrated a biphasic pattern of vascular permeability change: an early phase of permeability reduction and a later phase of permeability promotion at all dose levels tested. The India ink tracer technique also demonstrated a time-correlated increase in vascular labelling in the tissues examined, signifying an increase in vascular leakage with time. Moreover, we found that despite an early increase in tissue arsenic content at time of injection, tissue arsenic declined rapidly and returned to near control levels after 30-60 min. Thus, an inverse correlation between tissue arsenic content and the extent of vascular permeability was apparent. This study provides the first demonstration that in situ exposure to arsenic will produce vascular dysfunction (vascular leakage) in vivo.
The effects of diazinon on lipid peroxidation and antioxidant enzymes in erythrocytes in vitro
Authors: Altuntas Irfan , Kilinc Ibrahim , Orhan Hikmet , Demirel Reha , Koylu Halis , Delibas Namik
Published: March 2004

Diazinon is one of the most widely used organophosphate insecticides (OPI) in agriculture and public health programs. The aim of this study was to investigate how an OPI, diazinon, affects lipid peroxidation (LPO) and the antioxidant defense system in vitro. For this purpose, two experiments were carried out. In experiment 1, the effects of various concentrations of diazinon on LPO and the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) in erythrocytes were studied. Each diazinon concentration was incubated with a previously prepared erythrocyte samples at +4°C for 0, 60 and 180 min. After incubation, the malondialdehyde (MDA) levels and the activities of SOD, GSH-Px and CAT were determined. In experiment 2, in order to determine the direct effect of diazinon on the activities of SOD, GSH-Px and CAT, the erythrocytes were haemolysed and incubated with the various concentrations of diazinon at +4°C for 0, 60 and 180 min. In experiment 1, MDA levels and the activities of SOD and GSH-Px increased with increasing diazinon concentration and incubation period, but CAT activity remained unchanged. In experiment 2, SOD activity was significantly decreased, and GSH-Px activity was significantly increased. From these results, it can be concluded that in vitro administration of diazinon results in the induction of erythrocyte LPO and changes the activities of antioxidant enzymes, suggesting that reactive oxygen species may be involved in the toxic effects of diazinon.
The ability of fungal isolates from human lung aspergilloma to produce mycotoxins
Authors: Pepeljnjak S , Slobodnjak Z , Šegvić M , Peraica M , Pavlović M
Published: March 2004

This study included 11 adult patients (seven men and four women) who had been surgically treated for pulmonary aspergilloma in the Republic of Croatia within two years. Mycological analysis was positive for Aspergillus genus in five samples of surgically removed tissue. A. fumigatus was isolated in three and A. versicolor in two samples. Their mycotoxigenic potency was determined by thin layer chromatography. A. fumigatusstrains were found to produce aflatoxin B1 (AFB), and two of them aflatoxin G1. A. versicolor strains produced AFB1 and sterigmatocystin. Neither isolated Aspergillus strain produced aflatoxin G2 or ochratoxin A. Fungal growth and production of mycotoxins are the consequences of interaction of fungus, host and environment. One has also to take into consideration that the production of mycotoxins in vitro does not reflect what these fungi may produce in human organisms.
Investigation of biochemical and histopathological effects of Mentha piperitaLabiatae and Mentha spicata Labiatae on liver tissue in rats
Authors: Akdogan M , Ozguner M , Aydin G , Gokalp O
Published: March 2004

The plant Mentha piperita, or peppermint, is commonly used in the treatment of loss of appetite, common cold, bronchitis, sinusitis, fever, nausea and vomiting, and indigestion as a herbal agent. In this study, we aimed to investigate biochemical and histological effects of M. piperita Labiatae, growing in the Yenisar Bademli town of Isparta city, and Mentha spicata Labiatae, growing in the Anamas high plateau of the Yenisar Bademli town, on the rat liver tissue. Forty-eight male Wistar albino rats weighing 200-250 g were used for this study. Rats were divided into four groups of 12 animals: Group I received no herbal tea (control group); Group II received 20 g/L M. piperita tea; Group III received 20 g/L M. spicata tea; and Group IV received 40 g/L M. spicata tea. Herbal teas were prepared daily and provided at all times to the rats during 30 days as drinking water. Liver function tests, including aspartate aminotransferase (AST/GOT) and alanine aminotransferase (ALT/GPT) activities were measured. To evaluate liver antioxidant defences, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), cata lase (CAT) and thiobarbituric acid reactive substance (TBARS) activities were determined in the homogenates of liver tissue. In addition, liver tissues were submitted for histopathologic examination. AST and ALT activities were increased in Group II, Group III and Group IV gradually when compared with the control group. The difference between Group II and the control group was not statistically significant (P > 0.016). Increases in AST and ALT activities of Group III and Group IV were statistically significant when compared with the control group. SOD, GSH-Px and CAT activities were increased in Group II when compared with the control group but the difference was not statistically significant (P > 0.016). However, SOD, GSH-Px activities and the TBARS level were significantly increased, and CAT activity was significantly decreased in Group III when compared with the control group. In Group IV, while SOD, GSH-Px and CAT activities were decreased, the TBARS level was increased as compared with the control group (P < 0.0016). Histopathological evaluation of experimental groups revealed a mild to severe degree of hepatic damage when compared to the control group. In Group II, there was only minimal hepatocytes degeneration. In Groups III and IV, there were granular or ballooning hepatocyte degeneration and necrosis, sinusoidal and central vein dilatation. It was concluded that lipid peroxidation and hepatic damage occurs after M. piperita and M. spicata administration in rat liver and the damage seems to be dose dependent.
The effects of desferrioxamine on cisplatininduced lipid peroxidation and the activities of antioxidant enzymes in rat kidneys
Authors: Kadikoylu G , Bolaman Z , Demir S , Balkaya M , Akalin N , Enli Y
Published: March 2004

Cisplatin-induced nephrotoxicity is associated with an increase in lipid peroxidation and oxygen free radicals in rat kidneys. In this study, the effects of desferrioxamine were compared to vitamin C and E on cisplatin-induced lipid peroxidation and antioxidant enzyme activities in rat kidneys. Rats were divided into five groups, with 15 Wistar rats in each group. In the control group, rats received 1 mL/100 g isotonic saline solution intraperitoneally (i.p.). In Group II, 10 mg/kg cisplatin i.p. was injected to rats. Thirty minutes before the same dosage of cisplatin administration, 100 mg/kg i.p. vitamin C or E was given to rats in groups III and IV, respectively. Rats in Group V received 250 mg/kg desferrioxamine i.p., before the same dose of cisplatin administration. All rats were killed by cervical dislocation after 72 hours. The kidneys were immediately removed and washed in cold saline. Spectrophotometric method was used for all analyses. While catalase, glutathione reductase (GR), and super oxide dismutase (SOD) levels were found to be significantly decreased (P B < 0.001), malondialdehyde (MDA) (P < 0.05) and hydrogen peroxide (H2O2) (P < 0.001) levels were significantly increased in the cisplatin group when compared to the controls. MDA levels were decreased by desferrioxamine (P < 0.005) as well as vitamin C and E (P < 0.05 and P < 0.001, respectively). These three compounds induced a significant increase in SOD levels (P B < 0.05), but only in the vitamin C group, were SOD levels not significantly different than the levels of the controls (P > 0.05). In the desferrioxamine (P < 0.05), vitamin C and E groups (P < 0.001 for both), the cisplatin elevated H2O2 levels were decreased. None of these drugs had any effect on GR and catalase levels (P > 0.05). Desferrioxamine is useful to prevent cisplatin-induced lipid peroxidation, however, vitamin C and E are more effective on antioxidant enzymes than desferrioxamine.
Substitution for natural musk in Pien Tze Huang does not affect its hepatoprotective activities
Authors: Chan W Y , Chau F-t , Lee K KH , Kwong W H , Yew D T
Published: March 2004

Previous studies showed that Pien Tze Huang, a Chinese folk medicine well known for its therapeutic activity in treating liver diseases, protected the liver against carbon tetrachloride (CCl4)–induced damage in mice. In the present study, natural musk, one of the important ingredients of Pien Tze Huang, was replaced by a formulated substitute, and the new formulation of Pien Tze Huang was shown to have similar chromatographic patterns to the original Pien Tze Huang in gas chromatography–mass spectrometry and high performance liquid chromatography. When used in treating mice with CCl4–or galactosamine–induced liver damage, both the original and new formulations of Pien Tze Huang were found to be able to suppress to a similar extent both the histopathological changes in the liver and the elevation of serum alanine aminotransferase and aspartate amino–transferase. Necrosis, cellular ballooning, microvesicular steatosis and lymphocytes infiltration were all significantly reduced in the damaged liver. In hepatoma cells, both formulations activated the activator protein 1 (AP1) enhancer sequence, indicating that both of them were able to act through the JNK signal transduction pathway. The results of the present study showed that the substitution for natural musk does not affect the hepatoprotective activities of Pien Tze Huang. It is also postulated that both formulations protect the liver through regulating signal transduction in the cell.
The role of cytochrome–P450 inhibitors in the prevention of hepatotoxicity after paracetamol overdose in rats
Authors: Walubo A , Barr S , Abraham A M , Coetsee C
Published: March 2004

Despite the understanding that some cytochrome P450 isoforms are responsible for activation of paracetamol to the hepatotoxic metabolite, N–acetyl–p–benzoquinineimine (NAPQI), the use of enzyme inhibitors for prevention and/or treatment of paracetamol hepatotoxicity is still not well researched. Here, a mixture of ketoconazole, isoniazid and caffeine (inhibitor solution), known inhibitors of CYP3A, CYP2E1 and CYP1A2, was investigated for prevention of hepatotoxicity after paracetamol over–dose in rats. The appropriate doses of paracetamol (1000 mg/kg/day) and the ‘inhibitor solution’ (ketoconazole 5 mg/kg, isoniazid 5 mg/kg and caffeine 10 mg;kg;KIC–5–50), were selected in preliminary experiments. Thereafter, two groups of 15 male Sprague–Dawley rats each were treated with the toxic dose of paracetamol intraperitoneally to induce severe hepatotoxicity. But one of the two groups was treated with the KIC–5–50 intraperitoneally 5 min after administration of paracetamol. Five rats were killed at 24, 48 and 72 hours after paracetamol administration. Plasma concentrations of paracetamol were determined by the polarization fluorescent immunoassay and a piece of liver was sent for histopathology examination. Liver function tests at 48 hours were higher in the ‘paracetamol only’ treated group than in the ‘KIC–5–50+paracetamol’ treated group’ (P<0.05), i.e., median (range) AST 2025 (530–4329) g/mL for the ‘paracetamol only’ treated group versus 0.17 (0.07–0.33) μg/ml for the ‘KIC–5–50-paracetamol’ treated group. Centrilobular necrosis, the pathogmonomic feature of paracetamol hepatotoxicity, was demonstrated only in the ‘paracetamol only’ treated group. In conclusion, coadministration of paracetamol with inhibitors of cytochrome P450 prevented the development of paracetamol–induced hepatotoxicity in rats, and this calls for research for enzyme inhibitors that may be of therapeutic value.
Behavior of R/C Bridge Bent with Grade Beam Retrofit under Simulated Earthquake Loads
Authors: Pantelides Chris P. , Ward Jon P. , Reaveley Lawrence D.
Published: March 2004

Results from an in-situ lateral load test of a reinforced concrete bridge bent, whose design was inadequate under current seismic codes are presented. Details of a reinforced concrete grade-beam seismic retrofit design are provided. A nonlinear analysis model including soil-structure interaction predicted the experimental results with reasonable accuracy. Structural displacement ductility and that resulting from bent cap and foundation flexibility were compared to theoretical relations. Limiting strains and stresses for reinforcement in columns, bent-cap column joints, lap splices, and pile-cap column joints were measured and compared to the literature. Comparison of the experimental column plastic hinge length to predictive relationships shows that the latter slightly underestimate the measured plastic hinge length. Damage indices based on energy were used to evaluate the performance. Comparison with a test of a bridge bent without a grade beam retrofit shows that the foundation seismic retrofit was successful in enhancing the performance of the system.
Probabilistic Study on Accidental Torsion of Low-Rise Buildings
Authors: De-la-Colina Jaime , Almeida Cristina
Published: March 2004

A probabilistic study on accidental torsion is presented. Multistory shear systems, representative of low-rise buildings and subjected to bidirectional earthquake ground motions are considered. Ductility demands of lateral resisting elements (LREs) due to uncertainties on (1) center-of-mass locations, (2) LRE stiffness, and (3) LRE yield forces were studied. Building code recommendations on accidental torsion as well as the effects of both eccentricity and lateral-force reduction factor are assessed. Results indicate that considering one random variable in the accidental torsion problem can lead to larger ductility-demand probabilities of exceedance than using two or more variables. Individual effects of each one of the variables considered are not superimposed when all variables take place at the same time. For systems designed for torsion, ductility demands of LREs decreases for increasing eccentricities. Increments of yield forces and decrements of probabilities of exceedance due to the use of increasing values of factor β associated with the accidental eccentricity are presented.
Earthquake Performance of Porcelain Transformer Bushings
Authors: Whittaker Andrew S. , Fenves Gregory L. , Gilani Amir S. J.
Published: March 2004

The earthquake performance of 196-kV, 230-kV, and 550-kV porcelain transformer bushings was studied by earthquake-simulator experimentation and analysis. The fundamental frequencies of the 196-kV, 230-kV, and 550-kV bushings were identified to be approximately 15 Hz, 18 Hz, and 8 Hz, respectively, using resonance-search testing on the simulator. The corresponding damping ratios were between 2 and 4 percent of critical. The 196-kV and 230-kV bushings survived severe earthquake shaking and were qualified to the High Level per the IEEE 693-1997 standard. The discrepancy between excellent behavior in the laboratory and poor behavior in the field of these types of bushings calls into question the procedures used for qualification of substation equipment. The 550-kV bushing survived shaking at the moderate performance level with limited damage and minor oil leakage. Current procedures for fragility testing of transformer bushings were evaluated and found to be neither appropriate nor conservative.
The Effect of External Confinement on Flexural Hinging in Drilled Pile Shafts
Authors: Budek A. M. , Priestley M. J. N. , Benzoni G.
Published: March 2004

Six one-third-scale CIDH pile shafts were tested to simulate the subgrade moment pattern in an in situ pile shaft. The test fixture could also simulate the presence of external confinement provided by soil. Three levels of transverse reinforcement were tested. Three piles were tested with external confinement, and three without. The presence of external confinement played a significant role in enhancing flexural ductility by supporting the confining action of the transverse steel reinforcement. The presence of external confinement also increased the plastic hinge length, significantly reducing local curvature demand by allowing the hinge rotation requirements to be spread over a greater length of the pile shaft. In the absence of external confinement, the transverse reinforcement levels specified under current column design guidelines provided adequate flexural ductility for seismic response.
On the Seismic Vulnerability of Existing Buildings: A Case Study of the City of Basel
Authors: Lang Kerstin , Bachmann Hugo
Published: March 2004

In order to assess the seismic risk for Switzerland, and particularly for the city of Basel, the seismic vulnerability of the existing buildings needs to be evaluated. Since no major damaging earthquake has occurred in Switzerland in recent times, vulnerability functions from observed damage patterns are not available. A simple evaluation method based on engineering models of the building structures suitable for the evaluation of a larger number of buildings is therefore proposed. The method is based on a nonlinear static approach acknowledging the importance of the nonlinear deformation capacity of the buildings subjected to seismic action. Eighty-seven residential buildings in a small target area in Basel were evaluated. The results are vulnerability functions that express the expected damage as a function of the spectral displacement. In order to extrapolate the results to other residential areas of the town, building classes were defined for which the vulnerability is presented in a probabilistic form that can be used directly for earthquake scenario projects.
Azacitidine Induces Demethylation of the Epstein-Barr Virus Genome in Tumors
Authors: Chan Anthony T.C. , Tao Qian , Robertson Keith D. , Flinn Ian W. , Mann Risa B. , Klencke Barbara , Kwan Wing Hong , Leung Thomas Wai-Tong , Johnson Philip J. , Ambinder Richard F.
Published: March 2004

Purpose

To determine whether therapy with a DNA methyltransferase inhibitor is effective in achieving demethylation and gene re-expression in tumor DNA in patients.

Methods

Biopsy specimens were obtained from patients with Epstein-Barr virus-associated tumors, enrolled on a clinical trial of 5-azacitidine, within 72 hours of the conclusion of the last infusion of the first cycle of therapy, and compared to pretreatment specimens. Methylation-specific polymerase chain reaction, bisulfite genomic sequencing, and immunohistochemistry were used to assess demethylation and gene re-expression.

Results

Substantial degrees of demethylation were detected in all latent and lytic Epstein-Barr virus promoters examined. Immunohistochemistry suggested activation of a previously silent viral antigen expression in one instance.

Conclusion

Pharmacologic reversal of dense CpG methylation in tumor tissue can be achieved in patients.
Role of theBarhl2homeobox gene in the specification of glycinergic amacrine cells
Authors: Mo Zeqian , Li Shengguo , Yang Xuejie , Xiang Mengqing
Published: March 2004

The mammalian retina contains numerous morphological and physiological subtypes of amacrine cells necessary for integrating and modulating visual signals presented to the output neurons. Among subtypes of amacrine cells grouped by neurotransmitter phenotypes, the glycinergic andγ-aminobutyric acid (GABA)ergic amacrine cells constitute two major subpopulations. To date, the molecular mechanisms governing the specification of subtype identity of amacrine cells remain elusive. We report here that during mouse development, the Barhl2 homeobox gene displays an expression pattern in the nervous system that is distinct from that of its homologue Barhl1. In the developing retina, Barhl2expression is found in postmitotic amacrine, horizontal and ganglion cells,while Barhl1 expression is absent. Forced expression of Barhl2 in retinal progenitors promotes the differentiation of glycinergic amacrine cells, whereas a dominant-negative form of Barhl2 has the opposite effect. By contrast, they exert no effect on the formation of GABAergic neurons. Moreover, misexpressed Barhl2 inhibits the formation of bipolar and Müller glial cells, indicating that Barhl2 is able to function both as a positive and negative regulator, depending on different types of cells. Taken together, our data suggest that Barhl2 may function to specify the identity of glycinergic amacrine cells from competent progenitors during retinogenesis.
Accumulation and translation of ferritin heavy chain transcripts following anoxia exposure in a marine invertebrate
Authors: Larade Kevin , Storey Kenneth B.
Published: March 2004

Differential screening of a Littorina littorea (the common periwinkle) cDNA library identified ferritin heavy chain as an anoxia-induced gene in hepatopancreas. Northern blots showed that ferritin heavy chain transcript levels were elevated twofold during anoxia exposure, although nuclear run-off assays demonstrated that ferritin heavy chain mRNAs were not transcriptionally upregulated during anoxia. Polysome analysis indicated that existing ferritin transcripts were actively translated during the anoxic period. This result was confirmed via western blotting, which demonstrated a twofold increase in ferritin heavy chain protein levels during anoxia, with a subsequent decrease to control levels during normoxic recovery. Organ culture experiments using hepatopancreas slices demonstrated a >50%increase in ferritin heavy chain transcript levels in vitro under conditions of anoxia and freezing, as well as after incubation with the second messenger cGMP. Taken together, these results suggest that ferritin heavy chain is actively regulated during anoxia exposure in the marine snail, L. littorea.
Synthesis of Dimethyl Ether from Supercritical Methanol in the Presence of Aluminum
Authors: Usui Yuma , Wakai Chihiro , Matubayasi Nobuyuki , Nakahara Masaru
Published: March 2004

A novel method to synthesize dimethyl ether (DME) is presented. When methanol is treated with aluminum metal in supercritical conditions at a density of 0.39 kg/dm3, it is found that DME is generated above 275 °C through a single-step procedure. The DME production increases with the temperature elevation, and it becomes the main product above 300 °C with by-products of hydrogen and methane. DME is considered to be produced at the formation step of methyl derivative of boehmite and/or its surface catalytic effect.
Facile Preparation of Anion Trapping Polymer Electrolytes by Reaction between 9-Borabicyclo[3.3.1]nonane (9-BBN) and Poly(propylene oxide)
Authors: Mizumo Tomonobu , Sakamoto Kenji , Matsumi Noriyoshi , Ohno Hiroyuki
Published: March 2004

Novel polymer electrolyte showing relatively high lithium ion transference number of over 0.5 due to anion trapping effect of boron atoms was readily prepared by the reaction between poly(propylene oxide) oligomers and 9-borabicyclo[3.3.1]nonane.
Stably-dispersed and Surface-functional Bionanoparticles Prepared by Self-assembling Amphipathic Polymers of Hydrophilic Poly(γ-glutamic acid) Bearing Hydrophobic Amino Acids
Authors: Matsusaki Michiya , Hiwatari Ken-ichiro , Higashi Mariko , Kaneko Tatsuo , Akashi Mitsuru
Published: March 2004

Surface-functional bionanoparticles were prepared by self-assembling amphipathic poly(γ-glutamic acid) derivatives with a hydrophilic backbone and hydrophobic phenylalanine and leucine side groups. Poly(γ-glutamic acid) bearing phenylalanine nanospheres exhibited excellent water-dispersibility, surface functionality and appropriate size (200 nm) for medical use. Additive PEG conjugation assisted nanoparticle formation of leucine-grafted poly(γ-glutamic acid).
Epoxidation of Styrene by t-Butyl Hydroperoxide over Gold Supported on Yb2O3 and Other Rare Earth Oxides
Authors: Patil N S , Uphade B S , Jana P , Bhargava S K , Choudhary V R
Published: March 2004

Gold nanoparticles deposited [by homogeneous deposition-precipitation (HDP) using urea] on Yb2O3 and other rare-earth oxides (viz. Sm2O3, Eu2O3, and Tb2O3) are novel highly active/selective and reusable catalysts for the selective epoxidation of styrene to styrene oxide by anhydrous or aqueous t-butyl hydroperoxide and no problems are foreseen for a large scale operation of this green process.
Structures and Magnetic Properties of a New Cobalt(II) Linear Trimer with Phenylcinnamic Acid
Authors: Oka Yoshimi , Inoue Katsuya
Published: March 2004

Linear trinuclear cobalt(II) complex with α-phenylcinnamic acid (phcinaH), [Co3(phcina)6(quin)2] (quin = quinoline) was synthesized and characterized by X-ray crystallography and magnetic susceptibility measurement. The magnetic susceptibility of the linear trimer, which has one octahedral and two trigonal-bipyramidal coordination was analyzed by modified Lines model.
Regioselective Formation of Optically Active Cycloheptatrienes by Chiral Tethered Büchner Reaction
Authors: Sugimura Takashi , Ohuchi Naoko , Kagawa Masami , Hagiya Kazutake , Okuyama Tadashi
Published: March 2004

Optically active cycloheptatrienes were prepared by addition of the rhodium carbenoid to polysubstituted phenyl rings connected by a 2,4-pentanediol tether in sufficient regio- and stereoselectivity.
Synthesis and Stabilization of Ni Nanoparticles in a Pure Aqueous CTAB Solution
Authors: Wu Szu-Han , Chen Dong-Hwang
Published: March 2004

Ni nanoparticles (7–20nm) were synthesized by hydrazine reduction in a pure aqueous solution at 25 °C using CTAB as a capping agent and an appropriate amount of bases as catalysts. No organic solvents and extra inert gases were necessary. It was suggested that Ni nanoparticles were stabilized by a bilayer structure of CTAB.
Lifetime of Veratryl Alcohol Radical Cation Electrogenerated in Acetonitrile
Authors: Kishioka Shin-ya , Yamada Akifumi
Published: March 2004

The electrochemical oxidation of veratryl alcohol at a carbon fiber microdisk electrode with relatively high sweep rates in acetonitrile shows a chemically reversible response. Analysis of the cathodic and anodic current ratio allows one to estimate the lifetime of the short-lived radical cation in the solution.
Substituent Effect on Regioselectivity in Oxygenation of Multisubstituted Acenes
Authors: Zhou Xin , Kitamura Masanori , Shen Baojian , Nakajima Kiyohiko , Takahashi Tamotsu
Published: March 2004

Reaction of substituted acenes such as anthracene, naphthacene, and pentacene derivatives with O2 was dependent on the substituents and their positions. The orientation is in contrast to Diels–Alder reaction with DDQ in the case of naphthacene and pentacene derivatives. 1,2,3,4,5,6,7,8-Octamethylanthracene reacted with O2 to afford a doubly oxygenated compound (diendoperoxide) at both end rings.
Decomposition of Carbon Dioxide by the Dielectric Barrier Discharge (DBD) Plasma Using Ca0.7Sr0.3TiO3 Barrier
Authors: Li Ruixing , Tang Qing , Yin Shu , Yamaguchi Yukishige , Sato Tsugio
Published: March 2004

Ca0.7Sr0.3TiO3 was sintered adding Li2Si2O5, and used as a dielectric barrier of DBD to decompose CO2 for the first time. DBD plasma was successively generated using Ca0.7Sr0.3TiO3. CO2 was converted to CO and O2 by DBD plasma without catalyst and reducing substance. The CO2 conversion using Ca0.7Sr0.3TiO3 barrier was much higher than that using conventional barrier material such as SiO2 and Al2O3.
Synthesis of Macrocyclic Arylene Ketone Oligomers Containing the Phthaloyl Moiety by Friedel–Crafts Acylation Reaction
Authors: Guo Qingzhong , Bo Shuqin , Chen Tianlu
Published: March 2004

Two kinds of macrocyclic arylene ketone oligomers have been synthesized in high yield from phthaloyl dichloride and various bridge-linking electron-rich aromatic hydrocarbons via the modified Friedel–Crafts acylation reaction. The presence of a Lewis base in this reaction is demonstrated to be advantageous for forming macrocycle oligomers. These resultant oligomers can undergo melt ring-opening polymerization to give polymers with high Tg and excellent thermal stability.
The Studies on the Aqueous Dispersed Particles Formed from Monoolein/Monopalmitin/Water Mixture
Authors: Wang Zhining , Um Joom Y , Zheng Liqiang , Li Ganzuo
Published: March 2004

The morphology and the microstructure of the dispersed particles, which were formed from monoolein/monopalmitin/water mixture, have been studied. The freeze-fracture TEM shows clearly that the aqueous dispersed particles have irregular cubic shapes. X-ray diffraction technique has been utilized to study the microstructure of the particles and it was found that these particles still retained the cubic character.
Efficient Catalytic Reduction of Concentrated Nitric Acid on the Adsorption Sites of Activated Carbon
Authors: Miyazaki Akane , Shibazaki Kazumasa , Nakano Yoshio , Ogawa Mitsuteru , Balint Ioan
Published: March 2004

The adsorption sites of active carbon were found to promote efficiently the catalytic reduction of concentrated HNO3 by HCOOH at low temperature.
Generation of 1,6-Disilahexapentaene in the Reduction of an Overcrowded Bis(bromodiaryl)butadiyne Leading to the Unexpected Formation of 2-Allenyl-1-benzosilole
Authors: Mizuhata Yoshiyuki , Takeda Nobuhiro , Sasamori Takahiro , Tokitoh Norihiro
Published: March 2004

When the reductive debromination of an overcrowded bis(bromodiarylsilyl)butadiyne (2) bearing Tbt and Mes groups was performed with potassium graphite, the corresponding 2-allenyl-1-benzosilole (3) was isolated as a main product. The formation of 3 was most likely interpreted in terms of the initial generation of 1,6-disilahexapentaene (1) followed by the intramolecular double cyclization.
Morphology Control of Organic–Inorganic Hybrid Mesoporous Silica by Microwave Heating
Authors: Kim Dong-Jun , Chung Jin-Seong , Ahn Wha-Seung , Kang Gyoung-Won , Cheong Won-Jo
Published: March 2004

A periodic ordered mesoporous organosilica containing uniform ethane groups in the pore walls was prepared using microwave heating to produce 1.5–2.5-μm uniform particles with spherical morphology.
Rhodium-Catalyzed Acylation of Vinylsilanes with Acid Anhydrides: Application to the Transformation of α-Acyloxy Vinylsilanes to Unsymmetrical 1,2-Diketones
Authors: Yamane Motoki , Uera Kazuyoshi , Narasaka Koichi
Published: March 2004

Acylation of vinylsilanes with acid anhydrides is catalyzed by [RhCl(CO)2]2 to give α,β-unsaturated ketones. The application of this catalytic system to the acylation of α-acyloxy vinylsilanes affords α-acyloxy enones in good yields, which are converted to unsymmetrical 1,2-diketones or their mono acetals.
Extraction of Eu(III) and Tm(III) with picrolonic acid in methylisobutylketone
Authors: Ali Akbar
Published: March 2004

Picrolonic acid (HPA) in methylisobutylketone (MIBK) has been used for the extraction studies of Eu(III) and Tm(III) from pH 2 buffer solution. The composition of the organic adduct responsible for the extraction of these metal ions has been determined by slope analysis method that came out to be M(PA)3(M= Eu(III), Tm(III)). The effect of various anions and cations on the extraction of these metal ions has also been studied. Among the anions, fluoride, oxalate, citrate and cyanide ions masked the extraction, whereas Fe(III) Cu(II), Ni(II) and Co(II) has reduced the extraction. The formation constant of the organic adduct has also been calculated and discussed.
Adsorption of 60Co2+ on hydrous manganese oxide powder from aqueous solution
Authors: Granados Correa F. , Jiménez-Becerril J.
Published: March 2004

Hydrous manganese oxide (HMO) was synthesized and its ability to sorb 60Co2+ from aqueous solution was studied under static conditions as a function of contact time, cobalt concentration (10-2-10-7M), temperature (303-333K) and pH of adsorptive solution (2.2-11.4). X-ray diffraction was used in characterization of synthesized HMO. Low concentration of 60Co2+ solution, high pH and high temperature were the most favorable conditions for the adsorption process. The results show that the removal process is complete in 40 minutes, obeys a first order rate law and can be described using the Freundlich adsorption model. The standard enthalpy of the system was ΔH
0 = 12.5 ± 0.2 kJ mol-1 and cobalt desorption indicates that the uptake process proceeds via cation exchange. The removal of cobalt ions by HMO appears to be endothermic and irreversible. The values of calculated ΔG
0 and ΔS
0 were -17.0 ± 3.0 kJ mol-1 and (9.8 ± 0.2) × 10-2 kJ K-1 mol-1 respectively, this indicates spontaneity of the process and the degree of freedom of ions is increased by adsorption.
Simultaneous multi-element determination in some cosmetic samples of different origins using neutron activation analysis
Authors: El-Shazly E. A. A. , Abo Zahra Sh. F. , El-Sweify Fatima H. , Kanias G. D.
Published: March 2004

Instrumental neutron activation analysis (INAA) has been used to determine some trace, minor and major elements in some cosmetic samples. These samples have been randomly selected from the Egyptian market. Some of these cosmetics are imported from the world market and the others are manufactured in Egypt. Up to 25 elements have been quantitatively determined in selected cosmetic samples. These elements are: As, Br, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Sb, Sc, Sm, Rb, Ta, Tb, Th, U, W, Yb and Zn. Two certified standard reference materials have been used to assure the accuracy and precision of the technique, which are IAEA-405 and SL-1. Two different γ-radioactivity counting systems have been used and compared. Some of the analyzed samples contain some elements, which according to the list of the European Union must not be present in cosmetics. Moreover, some of these elements are present in a very high concentration. Thus, some of the analyzed samples contain arsenic, antimony, chromium and cobalt with the following respectively concentration ranges, in ppm, 0.37-3.67, 0.14-5.36, 2.94-29768 (∼3) and 0.52-4.12.
Radiolysis of an aqueous [11C]iomazenil solution
Authors: Fukumura Toshimitsu , Yamaguchi Masatoshi , Suzuki Kazutoshi
Published: March 2004

Radiolysis of [11C]iomazenil was investigated in an aqueous solution. Preparation of [11C]iomazenil with [11C]CH3I produced a good radiochemical yield, however, its radiochemical purity was always less than 90 without additives. This poor radiochemical purity was attributed to radiolysis of [11C]iomazenil. The degradation of [11C]iomazenil via radiolysis was markedly facilitated in the presence of HCOONa (strong selective hydroxyl radical and hydrogen atom scavenger). On the other hand, the radiolysis was suppressed effectively in the presence of NaNO3 (selective hydrated electron scavenger), suggesting participation of hydrated electrons in the radiolysis of [11C]iomazenil. LC/MS analysis of the degradation product suggested that the major degradation product by radiolysis had a molecular weight of 285 corresponding to the deiodinated compound. The present study showed that a decrease in the radiochemical purity of [11C]iomazenil was attributed to the radiolysis via the deiodination reaction by hydrated electron.
Measurement of cross sections of threshold detectors with spectrum average technique
Authors: Ağuş Y. , Çelenk İ. , Özmen A.
Published: March 2004

Cross sections of the reactions 103Rh(n, n′)103mRh, 115In(n, n′)115mIn, 232Th(n, f), 47Ti(n, p)47Sc, 64Zn(n, p)64Cu, 58Ni(n, p)58Co, 54Fe(n, p)54Mn, 46Ti(n, p)46Sc, 27Al(n, p)27Mg, 56Fe(n, p)56Mn, 24Mg(n, p)24Na, 59Co(n, α)56Mn, 27Al(n, α)24Na and 48Ti(n, p)48Sc were measured with average neutron energies above effective threshold by using the activation method through usage of spectrum average technique in an irradiation system where there are three equivalent Am/Be sources, each of which has 592 GBq activity. The cross sections were determined with reference to the fast neutron fission cross section of 238U. The measured values and published values are generally in agreement.
Ionic radii of heavy actinide(III) cations
Authors: Bilewicz A.
Published: March 2004

Experimentally determined ionic radii (r
i) of heavy actinides decrease irregularly with increasing of atomic number. In order to understand sources of this irregularity ionic radii of heavy actinides were compared with the radii of the maximum charge density (R
max) of the outermost orbital radii of these cations. From the linear dependence of ionic radii on 2j+1 weighted R
max of the 6p
1/2 and 6p
3/2 orbitals new values of r
i equal to 91.5 pm and 90.3 pm for Fm3+ and Md3+, respectively, were calculated.
Effect of the chemical state of uranium atom on the energy of spin-orbital splitting of its inner orbitals
Authors: Batrakov Yuri F. , Krivitsky Andrey G. , Pospelov Oleg V. , Puchkova Elena V.
Published: March 2004

Chemical shifts (ChSh) of nine emission lines of the uranium L-series in uranium oxides UO2+

x
(x=0-1) with respect to UO2 were studied by using a precise crystal-diffraction X-ray spectrometer. ChSh of Lα
1,α
2 uranium and thorium lines in solid solutions yUO2·(1-y )ThO2 (y=0:1) were measured with respect to UO2 and ThO2, respectively. The changes in energy of spin-orbital splitting (SOS) — Δδnl
± of inner nl-orbitals of the uranium atom were calculated from the data of ChSh of spin-doublet lines. For UO2+

x
oxides, a linear decrease in Δδnl
± values with increasing degree of uranium oxidation was found. Sign inversion of Δδnl
± for uranium levels was found on passing to solid solutions. No change in the SOS energy of inner thorium levels was detected. The values of Δδnl
± were found to correlate with the experimental values of the effective magnetic moment of uranium in oxides.

On the basis of the comparison of experimental Δδnl
± values with Dirac–Hartree–Fock atomic calculations, it was concluded that the observed variations in Δδnl
± values are due to the redistribution of electron and spin density between the 5f
7/2- and 5f
5/2-levels of the fine structure of the uranium atom without changes in atomic charge state. On the basis of the hypothesis of intraatomic relativistic U5f
7/2↔U5f
5/2 transition, a model of paramagnetic moment formation on the uranium atom in uranium dioxide was proposed.
Heterogeneous catalytic redox reactions of neptunium ions in the aqueous system HNO3-HCOOH
Authors: Ananiev A. V. , Shilov V. P. , Moisy Ph. , Madic Charles
Published: March 2004

The redox behaviours of neptunium(VI,V) ions in aqueous solutions containing nitric and formic acids in the presence of Pt/SiO2 catalyst have been studied. It was shown that neptunium(VI), being quite stable in 0.1-2.0M HNO3and 0.1-1.5M HCOOH, is reduced effectively to neptunium(V) inthe presence of ∼1 wt. % Pt/SiO2. In the presence of 0.05-0.5M urea (anti-nitrous agent) the reduction of neptunium(VI) proceeds to neptunium(IV) through the stage of the neptunium(V) formation. The effects of the solid-to-liquid mass to volume ratio, the concentration of urea, the concentration of nitricacid, the concentration of formic acid and the temperature on the rates of the Np(VI) and Np(V) reductions in the presence of ∼1 wt. % Pt/SiO2 were investigated. It was proposed that both reactions proceed through the stage of the HCOOH activated adsorption on Pt catalyst. Mechanisms of the Np(VI) and Np(V) catalytic reductions by formic acid were postulated.