bluuebunny/crossref_metadata_2025 huggingface dataset:
Flexural fatigue behavior of machinable and light‐activated hybrid composites for esthetic restorations
Authors: Yoshida Keiichi , Morimoto Nobuko , Tsuo Yukiko , Atsuta Mitsuru
Published: April 2004

The purpose of this study was to determine the flexural strength and flexural fatigue strength of a machinable composite (GN‐I) and three hybrid composites (Artglass, Estenia, and Gradia). Specimens (2 × 2 × 25 mm) were polymerized in a laboratory photo‐curing unit and then immersed in water at 37°C for 24 h, 6 months, and 1 year. After each immersion period, flexural strengths (4‐PFS) were measured at a cross‐head speed of 1 mm/min in 4‐point bending (span = 20 mm; distance between inside loading points = 10 mm). The cyclic fatigue test was performed at 2.0 Hz on a fatigue tester. The staircase method was employed for flexural fatigue strength (FFS) using a 5000 cyclic load limitation, 5‐MPa stress increment, and 20 specimens for each material. Both 4‐PFS and FFS of the machinable composite after all immersion periods were significantly greater than those of the three hybrid composites. The FFS results followed the same pattern as those of the 4‐PFS. The Estenia material exhibited the highest 4‐PFS and FFS after 24 h of immersion among three hybrid composites, whereas after 1 year of immersion, all three composites showed almost identical 4‐PFS and FFS statistically. A strong correlation was observed between 4‐PFS and FFS of the machinable composite and three hybrid resin composites. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 70B: 218–222, 2004
Improvement of endothelium‐dependent coronary vasodilation after a single LDL apheresis in patients with hypercholesterolemia
Authors: Igarashi Keiichi , Tsuji Masahiro , Nishimura Masaharu , Horimoto Masashi
Published: April 2004

The purpose of this study was to determine whether a single LDL apheresis would improve impaired endothelium‐dependent dilation of the coronary artery in patients with hypercholesterolemia. Hypercholesterolemia is associated with impaired endothelial function, and human studies using cholesterol‐lowering drugs indicate that endothelial function in the coronary arteries improves with reduction of serum LDL cholesterol over 6 to 12 months. The internal diameter of the left coronary artery and the coronary blood flow were measured by intracoronary Doppler‐wire measurement and quantitative angiography before and immediately after a single LDL apheresis in a population of 15 patients with familial hypercholesterolemia. Endothelium‐dependent vasodilation was assessed by intracoronary infusion of acetylcholine (1, 10, and 50 μg/min), and endothelium‐independent vasodilation was assessed by intracoronary bolus infusion of isosorbide dinitrate (2.5 mg) or papaverine (10 mg). A single 3‐hour LDL apheresis reduced serum LDL cholesterol by an average of 86.6 ± 1.7%. After the LDL apheresis, the changes in the coronary artery diameter and coronary blood flow in response to an infusion of 50 μg/min of acetylcholine increased significantly compared to the pre‐apheresis values (from −19.7 ± 4.8 to −2.9 ± 3.0% [P < 0.01] and from 80.7 ± 27.6 to 155.3 ± 23.5% [P < 0.01], respectively). The LDL apheresis did not significantly change the response of either parameter to infusion with isosorbide dinitrate or papaverine. The endothelial function of the epicardial coronary artery and the coronary microvasculature improved in hypercholesterolemic patients after only a single LDL apheresis, a procedure that markedly reduces the serum level of LDL cholesterol. J. Clin. Apheresis 19:11–16, 2004. © 2004 Wiley‐Liss, Inc.
Seasonal environmental changes modulate the prolactin receptor expression in an eurythermal fish
Authors: San Martín Rody , Cáceres Pilar , Azócar Rodrigo , Alvarez Marco , Molina Alfredo , Vera María I. , Krauskopf Manuel
Published: April 2004

Eurythermal fish have evolved compensatory responses to the cyclical seasonal changes of the environment. The complex adaptive mechanisms include the transduction of the physical parameters variations into molecular signals. Studies in carp have indicated that prolactin and growth hormone expression is associated with acclimatization, suggesting that the pituitary gland is a relevant physiological node in the generation of the homeostatic rearrangement that occurs in this adaptive process. Here, we report the cloning and characterization of a full‐length carp prolactin receptor cDNA, which codes for the long form of the protein resembling that found in mammalian prolactin receptors. We identified up to three receptor transcript isoforms in different tissues of the teleost and assessed cell‐ and temporal‐specific transcription and protein expression in carp undergoing seasonal acclimatization. The distinctive pattern of expression that carp prolactin receptor (cPRLr) depicts upon seasonal acclimatization supports the hypothesis that prolactin and its receptor are clearly involved in the new homeostatic stage that the eurythermal fish needs to survive during the cyclical changes of its habitat. © 2004 Wiley‐Liss, Inc.
How do glucocorticoids compare to oligo decoys as inhibitors of collagen synthesis and potential toxicity of these therapeutics?
Authors: Cutroneo Kenneth R. , Sterling Kenneth M.
Published: April 2004

This article demonstrates how glucocorticoids decrease collagen synthesis. The parameters used to assess procollagen synthesis in our laboratory will be compared to those used by others. This article will note all the pertinent literature on the molecular mechanisms of this down regulation of procollagen synthesis. For example, what are the effects of glucocorticoids at the levels of transcription and translation of collagen mRNAs? Finally, we will define a molecular mechanism to inhibit Type I collagen synthesis by decreasing the binding of the TGF‐β activator protein complex to the TGF‐β element in the distal promoter of the proα1 Type I collagen gene, preventing the 2:1 ratio of α1 to α2 chains in the processed Type I collagen molecule. We will next ask “How do sense oligo decoys decrease Type I collagen synthesis at the in vivo and at the cell levels?” In primary fibrotic cell culture, the double‐stranded phosphorothioate oligodeoxynucleotide decoys were more effective than their sense single‐stranded counterparts. The molecular mechanism for the decrease in Type I collagen synthesis is the same as glucocorticoids, that is by decreasing the binding of the TGF‐β activator protein complex to the TGF‐β element in the distal promoter of the proα1 Type I collagen gene for the transcription of the proα1 mRNAs. The reason for using sense oligo decoys as anti‐fibrotic agents as compared to the anti‐fibrotic glucocorticoids, is that presently marketed and FDA approved glucocorticoids have many untoward side effects which the sense oligo decoys do not have. © 2004 Wiley‐Liss, Inc.
Vascular endothelial growth factor expression in heart of rats exposed to hypobaric hypoxia: Differential response between mRNA and protein
Authors: Birot Olivier J.G. , Peinnequin André , Simler Nadine , Cuyck‐Gandré Hélène van , Hamel Rodolphe , Bigard Xavier A.
Published: April 2004

This study investigated the role of vascular endothelial growth factor (VEGF) in the neoangiogenesis induced in heart in response to hypoxia. The time‐course of adaptive changes in capillary supply, expression of VEGF mRNA and protein was studied in right (RV) and left ventricles (LV) of rats exposed to hypobaric hypoxia during 1–25 days (barometric pressure = 505 hPa). VEGF mRNA levels encoding for VEGF 188 and 164 isoforms were measured by reverse transcription‐polymerase chain reaction (RT‐PCR) and VEGF protein was determined by Western blotting. Relative RV weight (i.e., weight of RV related to body weight) increased with hypoxia and was 102% higher than in controls after 15 days of exposure (P < 0.01), while relative LV weight remained unaltered. A rapid and transient increase in VEGF 188 mRNA occurred after 1 day of hypoxia in LV (P < 0.05). Thereafter, a delayed increase in VEGF 188 mRNA expression occurred in RV (ANOVA, P < 0.001). By day 18, VEGF 188 mRNA level was higher in hypoxic than in control rats (P < 0.005) and then decreased to base line levels. Hypoxia did not affect the expression of VEGF 164 mRNA neither in LV nor in RV. One of the main results was that these hypoxia‐induced alterations in VEGF transcripts were not followed by associated increase in VEGF protein. These results suggest that capillary growth observed in RV after prolonged exposure to ambient hypoxia likely results from other molecular mechanisms than VEGF. © 2004 Wiley‐Liss, Inc.
Activity and expression of Xenopus laevis matrix metalloproteinases: Identification of a novel role for the hormone prolactin in regulating collagenolysis in both amphibians and mammals
Authors: Jung Jae‐Chang , West‐Mays Judith A. , Stramer Brian M. , Byrne Michael H. , Scott Sumi , Mody Mehernosh K. , Sadow Peter M. , Krane Stephen M. , Fini M. Elizabeth
Published: April 2004

Prolactin (PRL) has long been implicated in Xenopus metamorphosis as an anti‐metamorphic and/or juvenilizing hormone. Numerous studies showed that PRL could prevent effects of either endogenous or exogenous thyroid hormone (TH; T3). It has been shown that expression of matrix metalloproteinases (MMPs) is induced by TH during Xenopus metamorphosis. Direct in vivo evidence, however, for such anti‐TH effects by PRL with respect to MMPs has not been available for the early phase of Xenopus development or metamorphosis. To understand the functional role of PRL, we investigated effects of PRL on Xenopus collagenase‐3 (XCL3) and collagenase‐4 (XCL4) expression in a cultured Xenopus laevis cell line, XL‐177. Northern blot analysis demonstrated that XCL3 and XCL4 expression were not detected in control or T3‐treated cells, but were differentially induced by PRL in a dose‐ and time‐dependent fashion. Moreover, treatment with IL‐1α as well as phorbol myristate acetate (PMA), a protein kinase C (PKC) activator, or H8, a protein kinase A (PKA) inhibitor, augmented PRL‐induced collagenase expression, suggesting that multiple protein kinase pathways and cytokines may participate in PRL‐induced collagenase expression. Interestingly, XCL3 expression could be induced in XL‐177 cells by T3, but only when co‐cultured with prometamorphic Xenopus tadpole tails (stage 54/55), suggesting that the tails secrete a required intermediate signaling molecule(s) for T3‐induced XCL3 expression. Taken together, these data demonstrate that XCL3 and XCL4 can be differentially induced by PRL and T3 and further suggest that PRL is a candidate regulator of TH‐independent collagenase expression during the organ/tissue remodeling which occurs in Xenopus development. J. Cell. Physiol. 201: 155–164, 2004. © 2004 Wiley‐Liss, Inc.
8‐Cl‐cAMP and its metabolite, 8‐Cl‐adenosine induce growth inhibition in mouse fibroblast DT cells through the same pathways: Protein kinase C activation and cyclin B down‐regulation
Authors: Ahn Young‐Ho , Mok Jung Joong , Hwan Hong Seung
Published: April 2004

8‐Chloro‐cyclic AMP (8‐Cl‐cAMP) is known to be most effective in inducing growth inhibition and differentiation of a number of cancer cells. Also, its cellular metabolite, 8‐Cl‐adenosine was shown to induce growth inhibition in a variety of cell lines. However, the signaling mechanism that governs the effects of 8‐Cl‐cAMP and/or 8‐Cl‐adenosine is still uncertain and it is not even sure which of the two is the key molecule that induces growth inhibition. In this study using mouse fibroblast DT cells, it was found that adenosine kinase inhibitor and adenosine deaminase could reverse cellular growth inhibition induced by 8‐Cl‐cAMP and 8‐Cl‐adenosine. And 8‐Cl‐cAMP could not induce growth inhibition in the presence of phosphodiesterase (PDE) inhibitor, but 8‐Cl‐adenosine could. We also found that protein kinase C (PKC) inhibitor could restore this growth inhibition, and both the 8‐Cl‐cAMP and 8‐Cl‐adenosine could activate the enzymatic activity of PKC. Besides, after 8‐Cl‐cAMP and 8‐Cl‐adenosine treatment, cyclin B was down‐regulated and a CDK inhibitor, p27 was up‐regulated in a time‐dependent manner. These results suggest that it is not 8‐Cl‐cAMP but 8‐Cl‐adenosine which induces growth inhibition, and 8‐Cl‐cAMP must be metabolized to exert this effect. Furthermore, there might exist signaling cascade such as PKC activation and cyclin B down‐regulation after 8‐Cl‐cAMP and 8‐Cl‐adenosine treatment. © 2004 Wiley‐Liss, Inc.
Plasmalemmal vacuolar H+‐ATPase is decreased in microvascular endothelial cells from a diabetic model
Authors: Rojas Jose D. , Sennoune Souad R. , Martinez Gloria M. , Bakunts Karina , Meininger Cynthia J. , Wu Guoyao , Wesson Donald E. , Seftor Elisabeth A. , Hendrix Mary J.C. , Martínez‐Zaguilán Raul
Published: April 2004

Angiogenesis requires invasion of extracellular matrix (ECM) proteins by endothelial cells and occurs in hypoxic and acidic environments that are not conducive for cell growth and survival. We hypothesize that angiogenic cells must exhibit a unique system to regulate their cytosolic pH in order to cope with these harsh conditions. The plasmalemmal vacuolar type H+‐ATPase (pmV‐ATPase) is used by cells exhibiting an invasive phenotype. Because angiogenesis is impaired in diabetes, we hypothesized that pmV‐ATPase is decreased in microvascular endothelial cells from diabetic rats. The in vitro angiogenesis assays demonstrated that endothelial cells were unable to form capillary‐like structures in diabetes. The proton fluxes were slower in cells from diabetic than normal model, regardless of the presence or absence of Na+ and HCO and were suppressed by V‐H+‐ATPase inhibitors. Immunocytochemical data revealed that pmV‐ATPases were inconspicuous at the plasma membrane of cells from diabetic whereas in normal cells were prominent. The pmV‐ATPase activity was lower in cells from diabetic than normal models. Inhibition of V‐H+‐ATPase suppresses invasion/migration of normal cells, but have minor effects in cells from diabetic models. These novel observations suggest that the angiogenic abnormalities in diabetes involve a decrease in pmV‐ATPase in microvascular endothelial cells. © 2004 Wiley‐Liss, Inc.
Cadmium uptake in rat hepatocytes in relation to speciation and to complexation with metallothionein and albumin
Authors: Pham T.N.D. , Ségui J.A. , Fortin C. , Campbell P.G.C. , Denizeau F. , Jumarie C.
Published: April 2004

Cadmium (Cd) uptake has been studied in primary cultures of rat hepatocytes focusing on the impact of inorganic and organic speciation. Uptake time‐course studies over a 60‐min exposure to 0.3 μM 109Cd revealed a zero‐time uptake and a slower process of accumulation which proceeds within minutes. 109Cd uptake showed saturation kinetics (Km = 3.5 ± 0.8 μM), and was highly sensitive to inhibition by Zn and Hg. There was no evidence for sensitivity to the external pH nor for any preferential transport of the free cation Cd2+ over CdCln2–n chloro‐complexes. According to the assumption that only inorganic metal species are available, metal uptake decreased upon albumin (BSA) addition to the exposure media. In contrast, higher levels of 109Cd accumulation were obtained under optimal conditions for Cd complexation by MT. Comparison among uptake data obtained under inorganic and organic conditions revealed that Cd‐MT would be taken up 0.4 times as rapidly as Cdinorg. We conclude that uptake of Cd in rat hepatocytes involves specific transport mechanism(s) subjected to Zn or Hg interactions. Uptake of inorganic Cd is not proportional to the levels of free Cd2+ and does not involve the divalent cation transporter DCT1 nor the co‐transporter Fe2+‐H+ NRAMP2. We found Cd‐MT but not Cd‐BSA to be available for the liver cells, and have estimated a binding affinity four orders of magnitude higher for Cd complexation with MT compared to BSA; MT may have a significant role in Cd delivery to the liver. © 2004 Wiley‐Liss, Inc.
N‐acetylcysteine inhibits Na+ absorption across human nasal epithelial cells
Authors: Rochat Thierry , Lacroix Jean‐Silvain , Jornot Lan
Published: April 2004

N‐acetylcysteine (NAC) is a widely used mucolytic drug in patients with a variety of respiratory disorders. The mechanism of action is based on rupture of the disulfide bridges of the high molecular glycoproteins present in the mucus, resulting in smaller subunits of the glycoproteins and reduced viscosity of the mucus. Because Na+ absorption regulates airway surface liquid volume and thus the efficiency of mucociliary clearance, we asked whether NAC affects the bioelectric properties of human nasal epithelial cells. A 24‐h basolateral treatment with 10 mM of NAC decreased the transepithelial potential difference and short‐circuit current (ISC) by 40%, and reduced the amiloride‐sensitive current by 50%, without affecting the transepithelial resistance. After permeabilization of the basolateral membranes of cells with amphotericin B in the presence of a mucosal‐to‐serosal Na+ gradient (135:25 mM), NAC inhibited 45% of the amiloride‐sensitive current. The Na+‐K+‐ATPase pump activity and the basolateral K+ conductance were not affected by NAC treatment. NAC did not alter total cell mRNA and protein levels of α‐epithelial Na+ channel (EnaC) subunit, but reduced abundance of α‐ENaC subunits in the apical cell membrane as quantified by biotinylation. This effect can be ascribed to the sulphydryl (SH) group of NAC, since N‐acetylserine and S‐carboxymethyl‐l‐cysteine were ineffective. Given the importance of epithelial Na+ channels in controlling the thin layer of fluid that covers the surface of the airways, the increase in the fluidity of the airway mucus following NAC treatment in vivo might be in part related to downregulation of Na+ absorption and consequently water transport. J. Cell. Physiol. 201: 106–116, 2004. © 2004 Wiley‐Liss, Inc.
Efficient O‐ and N‐(β‐fluoroethylation)s with NCA [18F]β‐fluoroethyl tosylate under microwave‐enhanced conditions
Authors: Lu Shui‐Yu , Chin Frederick T. , McCarron Julie A. , Pike Victor W.
Published: April 2004

Reactions of no‐carrier‐added (NCA) [18F]β‐fluoroethyl tosylate with amine, phenol or carboxylic acid to form the corresponding [18F]N‐(β‐fluoroethyl)amine, [18F]β‐fluoroethyl ether or [18F]β‐fluoroethyl ester, were found to be rapid (2–10 min) and efficient (51–89% conversion) under microwave‐enhanced conditions. These conditions allow reactants to be heated rapidly to 150°C in a low boiling point solvent, such as acetonitrile, and avoid the need to use high boiling point solvents, such as DMSO and DMF, to promote reaction. The microwave‐enhanced reactions gave about 20% greater radiochemical yields than thermal reactions performed at similar temperatures and over similar reaction times. With a bi‐functional molecule, such as DL‐pipecolinic acid, [18F]β‐fluoroethyl tosylate reacts exclusively with the amino group. Copyright © 2004 John Wiley & Sons, Ltd.
Decrease in serum total cholesterol and increase in high‐density lipoprotein cholesterol in rats following moderate intake of sherry
Authors: Elorza Felix L , Jiménez‐Caliani Antonio , Jiménez‐Jorge Silvia , Naranjo Maria C , Naji Latifa , Estevez Maria I , Mateos‐Romero Jose M , Mateo Joaquin , Guerrero Juan M
Published: April 2004

Moderate intake of sherry by rats resulted in a decrease in serum total cholesterol and an increase in the proportion of high‐density lipoprotein cholesterol. Oloroso, manzanilla, fino and amontillado sherries all exerted similar effects. These effects were apparently not related to the ethanol content, since an aqueous solution of ethanol did not modify cholesterol levels. Therefore other compounds must be responsible for the effects observed. This paper shows that, in addition to typical red and white wines, sherries should be included in the list of wines with beneficial physiological effects following moderate consumption. Copyright © 2004 Society of Chemical Industry
The Biodeterioration of Synthetic Resins Used in Conservation
Authors: Cappitelli Francesca , Zanardini Elisabetta , Sorlini Claudia
Published: April 2004

Summary: Synthetic resins have been extensively employed by artists in their works of art, e.g. as paint binders, or by conservators for conservation treatments, e.g. as stone consolidants and protectives. It is generally thought that synthetic resins are less prone to chemical, physical and biological deterioration than other organic products but there are many articles in the scientific literature and some reports in the conservation of cultural heritage literature claiming that microorganisms are capable of degrading synthetic resins. This paper reviews the researches on the biodeterioration of synthetic resins used in the conservation of cultural heritage, including stone, painting and textile materials, carried out in the last fifty years.
New Hydrolyzable pH‐Responsive Cationic Polymers for Gene Delivery: A Preliminary Study
Authors: Veron Laurent , Ganée Arnaud , Charreyre Marie‐Thérèse , Pichot Christian , Delair Thierry
Published: April 2004

Summary: Here we want to report the synthesis and the characterization of 2‐methylacrylic acid 2‐(3‐imidazol‐1‐yl‐propionyloxy)ethyl ester (IPEMA), a new methacrylate derivative monomer bearing an hydrolyzable side chain terminated by an imidazole group. The kp/k value for its homopolymerization in N,N‐dimethylformamide at 60 °C was found to be 0.120 mol−1/2 · L1/2 · s−1/2. The free radical copolymerization of N,N‐dimethylaminoethyl methacrylate and this monomer was studied in N,N‐dimethylformamide at 60 °C, the reactivity ratios of this couple of monomers were determined to be rDMAEMA = 1.13 ± 0.09 and rIPEMA = 0.82 ± 0.09 (using distinct calculation methods). Molecular weights analysis, parallely with refractive index increments measurements, were performed to characterize the obtained polymers. Potentiometric titrations showed the ability of these copolymers to act as a ‘proton sponge’. Preliminary study of the copolymers hydrolysis proved that imidazole units could be slowly cleaved from the polymer backbone at 37 °C in neutral aqueous buffer. Agarose gel electrophoresis of plasmid DNA/polymer complexes demonstrated the DNA complexing properties of these imidazole‐based copolymers.

Reaction scheme of the synthesis of IPEMA monomer.

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Reaction scheme of the synthesis of IPEMA monomer.
Synthesis of Nanosized Chitosan‐Poly(acrylic acid) Particles by a Dropping Method
Authors: Chang Tao‐Chih , Wang Jian‐Wen , Hon Min‐Hsiung
Published: April 2004

Summary: Deoxyribonucleic acid (DNA) vaccines are being investigated extensively because of their excellent potential over conventional protein ones. A suitable DNA carrier, consisting of uniformly dispersed chitosan‐poly(acrylic acid) particles with an average size of 30 nm, was successfully synthesized by a dropping method with a ratio of chitosan solution to poly(acrylic acid) solution of 1:1 and was incubated in a buffer solution with a pH value of 3.0. The particle size increased from 35.76 to 45.90 nm when the pH value of the buffer solution was increased from 3.0 to 7.4. After freeze‐drying, the non‐incubated mixed solution showed a membranous morphology. A powdered product was formed from the mixed solution as incubated in buffer solution with pH values of 3.0 and 5.3. However, when the mixed solution was incubated in a buffer solution of pH 7.4, a mixture of membrane and powder was obtained.

TEM micrograph of the dried CS‐PAA solution incubated in PBA solution with pH 3.0.

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TEM micrograph of the dried CS‐PAA solution incubated in PBA solution with pH 3.0.
Encapsulation and/or Release Behavior of Bovine Serum Albumin within and from Polylactide‐Grafted Dextran Microspheres
Authors: Ouchi Tatsuro , Saito Toshifumi , Kontani Tomohiro , Ohya Yuichi
Published: April 2004

Summary: Polylactide (PLA)‐grafted dextran (Dex‐graft‐PLA) of various contents of sugar units was synthesized by anionic polymerization of L‐lactide (L‐LA) using the alkoxide of partially trimethylsilylated dextran (TMSDex) and subsequently removing the trimethylsilyl (TMS) groups. The copolymer showed different solubility from L‐LA homopolymer with increasing the content of sugar units. We prepared bovine serum albumin (BSA)‐loaded microspheres (MS)s according to a water‐in‐oil‐in‐water emulsion‐solvent evaporation/extraction method using methylene chloride/DMSO as an organic cosolvent. MSs prepared from Dex‐graft‐PLA [MS(Dex‐graft‐PLA)s] exhibited higher loading efficiency of BSA than MSs prepared from PLLA [MS(PLLA)s]. The in vitro release rate of BSA from MS(Dex‐graft‐PLA) was faster than that from MS(PLLA). BSA released from MS(Dex‐graft‐PLA) maintained the secondary structure of native BSA to a great extent, compared with BSA released from MS(PLLA).

Confocal fluorescence images of the differential interference micrographs over the fluorescence images of MS(PLLA) and MS(Dex‐graft‐PLA).

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Confocal fluorescence images of the differential interference micrographs over the fluorescence images of MS(PLLA) and MS(Dex‐graft‐PLA).
Polyacrylonitrile/Nylon 6 Blends: Preparation and Characterization
Authors: Sainath Annadanam V. Sesha , Inoue Takashi , Hatakeyama Yoshiharu , Shishido Masahiro , Okamoto Kenzo , Kawaguchi Seigou , Kuriyama Takashi , Koyama Kiyohito
Published: April 2004

Summary: Polyacrylonitrile (PAN) particles with micro‐size ranges (0.15–2 μm) were prepared by emulsion and dispersion polymerizationa and in supercritical carbon dioxide media. The PAN particles were blended with Nylon 6 (PA6) at 220 °C by using a miniature mixer; it was found that melt‐mixing was possible for PAN‐rich compositions as high as 70 wt.‐%. Blends were characterized by scanning electron microscopy, IR, viscosity measurements, differential scanning calorimetry, and dynamic mechanical thermal analysis (DMTA). The size and shape of original PAN particles were retained in PAN/PA6 blends. The useful range to blend PAN particles size was less than 1 μm in terms of shape retention of the PAN particles in blends. Blends with 40 wt.‐% PAN content were found to be melt‐processable. The elastic modulus was higher for PAN/PA6 blends than pure PA6.

SEM photograph of PAN‐SC/PA6 blend with a 40/60 weight ratio.

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SEM photograph of PAN‐SC/PA6 blend with a 40/60 weight ratio.
Synthesis of Poly(2,5‐benzimidazole) for Use as a Fuel‐Cell Membrane
Authors: Kim Hyoung‐Juhn , Cho Sung Yong , An Sung Jin , Eun Yeong Chan , Kim Ju‐Yong , Yoon Hae‐Kwon , Kweon Ho‐Jin , Yew Kyoung Han
Published: April 2004

Summary: Poly(2,5‐benzimidazole) (ABPBI) was synthesized in a novel polymerization medium containing CH3SO3H and P2O5. 3,4‐Diaminobenzoic acid, a monomer for ABPBI, is soluble in the medium and the polymerization was therefore performed in a homogeneous state. It produced polymer fibers, thus simplifying the work‐up process. The membrane was cast directly from the polymerization mixture. Proton conductivities of the ABPBI membranes ranged from 0.02 to 0.06 S · cm−1 above 100 °C, without humidification, and the tensile strength of the membrane was approximately 100 MPa.

Synthesis of ABPBI in a medium containing methanesulfonic acid and P2O5.

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Synthesis of ABPBI in a medium containing methanesulfonic acid and P2O5.
Transdermal apomorphine permeation from microemulsions: A new treatment in Parkinson's disease
Authors: Priano Lorenzo , Albani Gianni , Brioschi Andrea , Calderoni Sara , Lopiano Leonardo , Rizzone Mario , Cavalli Roberta , Gasco Maria Rosa , Scaglione Francesco , Fraschini Franco , Bergamasco Bruno , Mauro Alessandro
Published: April 2004

We studied absorption, efficacy, and tolerability in Parkinson's disease (PD) of a new preparation of apomorphine included in a microemulsion and administered by transdermal route (Apo‐MTD). Twenty‐one PD patients were treated with levodopa plus oral dopamine‐agonists (T0), with levodopa alone (T1), finally with levodopa plus Apo‐MTD (T2). Apo‐MTD provided therapeutic plasma levels for many hours, improved Unified Parkinson's Disease Rating Scale III scores, and reduced total duration of off periods compared to T0 and T1. We concluded that Apo‐MTD is absorbed and demonstrates clinical efficacy and long action. Therefore, it seems a promising add‐on treatment for uncontrolled prolonged off phases in PD patients, but chronic tolerability needs further study. © 2004 Movement Disorder Society
Patient‐based outcomes of cervical dystonia: A review of rating scales
Authors: Cano Stefan J. , Hobart Jeremy C. , Fitzpatrick Ray , Bhatia Kailash , Thompson Alan J. , Warner Thomas T.
Published: April 2004

Decisions on treatment choice for patients are based on trials and outcome studies that are wholly dependent upon the scientific quality of the rating scales used. This study reviewed rating scales used in cervical dystonia outcome research to determine the extent that they satisfy recommended criteria for rigorous measurement. © 2004 Movement Disorder Society
Most effective stimulation site in subthalamic deep brain stimulation for Parkinson's disease
Authors: Herzog Jan , Fietzek Urban , Hamel Wolfgang , Morsnowski Andre , Steigerwald Frank , Schrader Bettina , Weinert Dieter , Pfister Gerd , Müller Dieter , Mehdorn Hubertus M. , Deuschl Günther , Volkmann Jens
Published: April 2004

The optimal stimulation site in subthalamic deep brain stimulation (STN‐DBS) was evaluated by correlation of the stereotactic position of the stimulation electrode with the electrophysiologically specified dorsal STN border. In a series of 25 electrodes, best clinical results with least energy consumption were found in contacts located in the dorsolateral border zone, whereas contacts within the subthalamic white matter, e.g., zona incerta, were significantly less effective. We suggest that the dorsolateral STN border should be covered by STN‐DBS. © 2004 Movement Disorder Society
A “cure” for Parkinson's disease: Can neuroprotection be proven with current trial designs?
Authors: Clarke Carl E.
Published: April 2004

Current medical and surgical therapies for Parkinson's disease provide symptomatic control of motor impairments rather than slowing or halting the progression of the disease. Previous clinical trials examining drugs such as dopamine agonists and selegiline for neuroprotective effects used “surrogate” outcomes, including clinical measures (rating scales, time to require levodopa), neuroimaging techniques (β‐CIT single photon emission computed tomography; fluorodopa positron emission tomography), and mortality tracking. These studies failed to provide conclusive results because of design faults such as failing to control for symptomatic effects, small sample size, and not accounting for the possible effects of drugs on radionuclide tracer handling. Lessons must be learned from these failed neuroprotection trials. This review summarises the problems with previous neuroprotection studies and makes recommendations for future trial design. It is concluded that the primary outcome of explanatory trials should continue to be clinical measures such as the Unified Parkinson's Disease Rating Scale (UPDRS). It should be assumed that all agents have a symptomatic effect, which necessitates evaluation after a prolonged drug washout period. To achieve the evaluation after a prolonged drug washout period more effectively, trials must be performed in early disease and over a short period (6–12 months) so that symptomatic therapy is not required. To achieve adequate statistical power, these trials will need to include thousands of patients. Radionuclide imaging can only be used in such trials after considerable methodological work has been performed to establish its validity and reliability. To be affordable, such large explanatory trials need more streamlined designs with fewer hospital visits, fewer outcome measures, and rationalised safety monitoring. The clinical effectiveness of promising compounds from explanatory trials will need to be established in large long‐term pragmatic trials using outcome measures such as quality of life, cost‐effectiveness, and mortality. Such pragmatic trials could be continuations of the explanatory trials: after the primary outcome of the explanatory study (e.g., UPDRS) has been reported in an interim analysis, the trial could be continued for a further 5 to 10 years to report on quality of life and health economics outcomes. © 2004 Movement Disorder Society
Patterns of EMG–EMG coherence in limb dystonia
Authors: Grosse Pascal , Edwards M. , Tijssen M.A.J. , Schrag A. , Lees Andrew J. , Bhatia K.P. , Brown Peter
Published: April 2004

Dystonia of the limbs may be due to a wide range of aetiologies and may cause major functional limitation. We investigated whether the previously described pathological 4 to 7 Hz drive to muscles in cervical dystonia is present in patients with aetiologically different types of dystonia of the upper and lower limbs. To this end, we studied 12 symptomatic and 4 asymptomatic carriers of the DYT1 gene, 6 patients with symptomatic dystonia due to focal basal ganglia lesions, and 11 patients with fixed dystonia, a condition assumed to be mostly psychogenic in aetiology. We evaluated EMG–EMG coherence in the tibialis anterior (TA) of these and 15 healthy control subjects. Ten of 12 (83%) of symptomatic DYT1 patients had an excessive 4 to 7 Hz common drive to TA, evident as an inflated coherence in this band. This drive also involved the gastrocnemius, leading to co‐contracting electromyographic bursts. In contrast, asymptomatic DYT1 carriers, patients with symptomatic dystonia, patients with fixed dystonia, and healthy subjects showed no evidence of such a drive or any other distinguishing electrophysiological feature. Moreover, the pathological 4 to 7 Hz drive in symptomatic DYT1 patients was much less common in the upper limb, where it was only present in 2 of 6 (33%) patients with clinical involvement of the arms. We conclude that the nature of the abnormal drive to dystonic muscles may vary according to the muscles under consideration and, particularly, with aetiology. © 2004 Movement Disorder Society
Mistaken diagnosis of psychogenic gait disorder in a man with status cataplecticus ("Limp Man Syndrome")
Authors: Simon David K. , Nishino Seiji , Scammell Thomas E.
Published: April 2004

We report on a 45‐year‐old man with a history of multiple psychiatric admissions for a gait disorder and episodic weakness thought to be psychogenic who was subsequently diagnosed with status cataplecticus due to narcolepsy. The gait difficulties resolved with venlafaxine. This case demonstrates that status cataplecticus can be misdiagnosed as a psychogenic gait disorder. © 2004 Movement Disorder Society
Segmental dystonia induced by wearing glasses with a ribbon: An unusual case of a reverse sensory geste
Authors: Wider Christian , Ghika Joseph , Bogousslavsky Julien , Vingerhoets François
Published: April 2004

Craniocervical muscles are the most frequently involved in dystonia, which can be either focal of segmental. While often experiencing an increase in dystonia with voluntary motor activity, many patients report temporary relief with geste antagoniste. We describe a patient who presented a peculiar craniocervical segmental dystonia, triggered by putting on glasses with a ribbon. © 2004 Movement Disorder Society
Test–retest reliability of UPDRS‐III, dyskinesia scales, and timed motor tests in patients with advanced Parkinson's disease: An argument against multiple baseline assessments
Authors: Metman Leo Verhagen , Myre Brian , Verwey Niek , Hassin‐Baer Sharon , Arzbaecher Jean , Sierens Diane , Bakay Roy
Published: April 2004

The primary objective of this study was to assess the intra‐rater reliability of the motor section of the Unified Parkinson's Disease Rating Scale (UPDRS‐III) in patients with advanced Parkinson's disease (PD). The secondary objective was to assess the intra‐rater reliability of standard timed motor tests and dyskinesia scales to determine the necessity of multiple baseline core evaluations before surgery for PD. We carried out two standardized preoperative core evaluations of patients with advanced PD scheduled to undergo deep brain stimulation. Patients were examined in the defined off and on conditions by the same rater. UPDRS‐III, timed tests, and dyskinesia scores from the two evaluations were compared using Wilcoxon Signed Ranks tests and intraclass correlation coefficients (ICC). Differences in UPDRS‐III scores for the two visits were clinically and statistically nonsignificant, and the ICC was 0.9. Similarly, there were no significant differences in timed motor tests or dyskinesia scores, with a median ICC of 0.8. The results indicate that previous findings of high test–retest reliability of UPDRS‐III in early untreated PD patients can now be extended to those with advanced disease complicated by motor fluctuations. In addition, test–retest reliability of dyskinesia scales and timed motor tests was high. Taken together, these findings challenge the need for multiple baseline assessments as currently stipulated in core assessment protocols for surgical intervention in PD. © 2004 Movement Disorder Society
Norm behaviour of solutions to a parabolic–elliptic system modelling chemotaxis in a domain of ℝ3
Authors: Chen Hua , Zhong Xinhua
Published: April 2004

In this paper, we study a parabolic–elliptic system defined on a bounded domain of ℝ3, which comes from a chemotactic model. We first prove the existence and uniqueness of local in time solution to this problem in the Sobolev spaces framework, then we study the norm behaviour of solution, which may help us to determine the blow‐up norm of the maximal solution. Copyright © 2004 John Wiley & Sons, Ltd.
Non‐empirical calculations of NMR indirect carbon–carbon coupling constants. Part 7—Spiroalkanes
Authors: Krivdin Leonid B.
Published: April 2004

Carbon–carbon spin–spin coupling constants were calculated at the SOPPA level for a series of seven classical spiroalkanes, spiro[2.2]pentane, spiro[2.3]hexane, spiro[2.4]heptane, spiro[2.5]octane, spiro[3.3]heptane, spiro[4.4]nonane and spiro[5.5]undecane, with special focus upon couplings involving and/or across spiro carbons. Many interesting structural trends were investigated originating in specific geometries and unusual bonding environments at the spiro carbon. Copyright © 2004 John Wiley & Sons, Ltd.
19F and 1H NMR spectra of halocarbons
Authors: Foris Anthony
Published: April 2004

19F NMR chemical shifts and coupling constants are reported for 215 compounds. For 77 of these compounds, 1H NMR spectral data are also given. Long‐range couplings, including 8J(F,F) and 5J(F,H), are reported. The complexity of halocarbon spectra owing to the presence of rotational isomers, asymmetric centers, long‐range couplings, and chlorine isotope effects are illustrated, and the methods used for analyzing such complex spectra are briefly discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Assignment of the relative configuration of spiro[4.5]decanes by 13C, 15N and 17O NMR
Authors: Guerrero‐Alvarez Jorge Antonio , Moncayo‐Bautista Antonio , Ariza‐Castolo Armando
Published: April 2004

The relative configuration of 11 1,4‐diazaspiro[4.5]decanes (1a–1j and 1m), 15 1,4‐oxazaspiro[4.5]decanes (2a–2o) and 10 1,4‐dioxaspiro[4.5]decanes (3a–3n) substituted at the 2‐, 6‐, 7‐ or 8‐position by a methyl group or using the tert‐butyl group as a model for the ananchomeric structure is reported. The relative stereochemistry was analyzed by 1H, 13C, 15N and 17O NMR and all isomers present were characterized spectroscopically. Compounds with a methyl group in the six‐membered ring show a chair conformation preference with the methyl group in the equatorial position. Compounds with one or two nitrogens exhibit a tautomeric equilibrium between the imine–diazolidine forms, as demonstrated by IR and 13C NMR. Copyright © 2004 John Wiley & Sons, Ltd.
Complete 1H and 13C assignments of 8‐C‐β‐D‐[2‐O‐(E)‐p‐coumaroyl]glucopyranosyl‐2‐(2‐hydroxy)propyl‐7‐methoxy‐5‐methylchromone
Authors: Meng Y. , Yan B. Z. , Wang H. M. , Hu G. F. , Liu F. Y. , Song Y. G. , Liu Y.
Published: April 2004

1H and 13C NMR spectra of 8‐C‐β‐D‐[2‐O‐(E)‐p‐coumaroyl] glucopyranosyl‐2‐(2‐hydroxy)propyl‐7‐methoxy‐5‐methylchromone were completely assigned by 2D NMR observations. Especially the 1H assignments of the glucosyl and hydroxyl protons were achieved by utilizing HMQC, HMBC, 1H–1H COSY and DEPT techniques together with a heavy water exchange 1H NMR experiment. Copyright © 2004 John Wiley & Sons, Ltd.
Involvement of ERK1/2 pathway in TGF‐β1‐induced VEGF secretion in normal human cytotrophoblast cells
Authors: Qian Dong , Lin Hai‐Yan , Wang Hong‐Mei , Zhang Xuan , Liu Dong‐Lin , Li Qing‐Lei , Zhu Cheng
Published: April 2004

Transforming growth factor‐β1 (TGF‐β1) plays a pivotal role in the angiogenesis during the development of placenta, but the intracellular signaling mechanism by which TGF‐β1 stimulates this process remains poorly understood. In this article, we demonstrated that exposure of normal human cytotrophoblast cells to TGF‐β1 stimulated the secretion of the VEGF gene encoding vascular endothelial growth factor, which is a key factor in angiogenesis. Meanwhile, treatment of normal human cytotrophoblast cells with TGF‐β1‐induced expression of HIF‐1a, the regulated subunit of hypoxia‐inducible factor 1, a known transactivator of the VEGF gene. Our data indicated that TGF‐β1 induced extracellular signal‐ regulated kinase (ERK) 1/2 phosphorylation in normal human cytotrophoblast cells. Moreover, treating cells with PD98059, an inhibitor of ERK1/2 signaling, inhibited TGF‐β1 stimulation of VEGF secretion and HIF‐1a protein expression. These data indicated that in normal human cytotrophoblast cells, TGF‐β1 induced HIF‐1a‐mediated VEGF secretion, and TGF‐β1‐stimulated‐ERK1/2 activation may be involved in this process. Mol. Reprod. Dev. 68: 198–204, 2004. © 2004 Wiley‐Liss, Inc.
Chromatin, microtubules, and kinases activities during meiotic resumption in bitch oocytes
Authors: Saint‐Dizier Marie , Reynaud Karine , Chastant‐Maillard Sylvie
Published: April 2004

In contrast to the majority of mammals, canine oocytes are ovulated at immature germinal vesicle (GV) stage and complete meiotic maturation to metaphase II during 48–72 hr within the oviducts. This study aims to characterize meiotic maturation process in bitch oocytes, with both morphological and biochemical approaches. The follow‐up of chromatin and microtubules during maturation was described, and MPF and MAP kinase activities were quantified at different stages of maturation. Since bitch oocyte cytoplasm is darkly pigmented, the first step was to setup an appropriate staining method for DNA. We thus compared the efficiency of two visualization techniques and demonstrated that propidium iodide coupled to confocal microscopy was a better method than Hoechst/fluorescence microscopy for nuclear stage observation (determination rates: 98.6 vs. 69.5%, respectively; P < 0.01, n = 1622 oocytes). Microtubule organization, evaluated by tubulin immunodetection, revealed subcortical and perinuclear α‐tubulin and asters in GV oocytes and a clear network of microtubules in GVBD oocytes. In MI and MII oocytes, a symmetrical, barrel‐shaped, and radially located spindle was observed. MPF and MAP kinase activities were assayed concomitantly using histone H1 and MBP as substrates. Kinase activities were detected at low levels in oocytes at GV and GVBD stages and were significantly higher at MI and MII stages. In conclusion, despite the particular pattern of meiotic resumption in canine oocytes (ovulated at GV stage), cytoskeleton/chromatin organization and kinase activities follow a similar pattern to those observed in other mammalian species. Mol. Reprod. Dev. 68: 205–212, 2004. © 2004 Wiley‐Liss, Inc.
Vitelline envelope gps 63 and 75 specifically bind sperm in “in vitro” assays in discoglossus pictus
Authors: Infante Vincenzo , Caputo Mariangela , Riccio Stefania , de Filippis Anna , Carotenuto Rosa , Vaccaro Maria Carmen , Campanella Chiara
Published: April 2004

In Xenopus, conflicting data related to sperm–vitelline envelope (VE) binding suggest that further experiments should be performed to study the role of VE glycoproteins in sperm binding. In this article, we studied the VE of Discoglossus pictus, where gp63, the product of the Dp ZP2 gene, has high molecular identity to Xenopus gp69/64 and to mouse ZP2 and only A23187‐treated sperm bind to VE. Sperm bind to VE all over the egg, yet a sperm tuft was found only in the animal half of the egg, where the dimple, the site of fertilization, is located and an intense immunostain was detected in VE by an antiserum directed against gp69/64. The same antiserum inhibited sperm binding to VE. Sperm binding to beads coated with gp63, gp40, or gp75 was in the range of 62–70% for gp63‐beads, 67–75% for 75 beads, and about 20% for BSA beads and gp40‐coated beads. Soluble purified gp63 and gp75 competitively inhibited binding of sperm to gp63‐coated beads. Similarly, the same glycoproteins inhibited sperm binding to gp75‐coated beads. SDS–polyacrylamide gels (PAGE) of FE and comparison of VE and FE peptide maps showed that gp63 undergoes a minor shift to about 62 kDa in FE. In sperm binding assays with beads coated with FEs gp62, there was no binding. Following fertilization, in the region of the dimple, an F‐layer is formed as well as an alteration of the VE structure. Lectin blots of the FE showed that the FE and in particular gp62 acquires a stronger affinity to Maackia amurensis agglutinin (MAA) with respect to VEs gp63. These results indicate that gps 63 and 75 are the sperm binding glycoproteins of D. pictus VE, where major post‐fertilization changes occur as in other anuran species. Mol. Reprod. Dev. 68: 213–222, 2004. © 2004 Wiley‐Liss, Inc.
Increased luminal pH in the epididymis of infertile c‐ros knockout mice and the expression of sodium–hydrogen exchangers and vacuolar proton pump H+‐ATPase
Authors: Yeung Ching‐Hei , Breton Sylvie , Setiawan Iwan , Xu Yaoxian , Lang Florian , Cooper Trevor G.
Published: April 2004

Transgenic mice targeted for the c‐ros gene, which are fertile when heterozygous (HET), but infertile when homozygous (knockout, KO) and associated with failure in pubertal differentiation of the epididymal initial segment, provide a model for studying the role of the epididymal luminal environment in sperm development. Luminal fluid from the cauda epididymidis was measured by both ion‐selective microelectrodes and pH strips to be 0.3 pH units higher in the KO than HET. Of the genes responsible for luminal acidification, expression of mRNA of vacuolar H+‐ATPase was found in all epididymal regions, but with no difference between KO and HET. Immunohistochemistry showed its presence in epithelial apical cells and clear cells. The Na+–hydrogen exchanger NHE2 was expressed at mRNA and protein levels in the caput but only marginally detectable if at all in the distal epididymis. This was compensated for by NHE3 which was expressed strongest in the cauda region, in agreement with immunohistochemical staining. Quantification of Western blot data revealed slight, but significant, decreases of NHE2 in the caput and of NHE3 in the cauda in the KO mice. The increase in luminal fluid pH in the KO mice could also be contributed to by other epithelial regulating factors including the Na+‐dependent glutamate transporter EAAC1 formerly reported to be down regulated in the KO. Mol. Reprod. Dev. 68: 159–168, 2004. © 2004 Wiley‐Liss, Inc.