bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract8‐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

AbstractAngiogenesis 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

AbstractCadmium (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

AbstractN‐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

AbstractReactions 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

AbstractModerate 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

AbstractSummary: 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

AbstractSummary: 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.imageReaction 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

AbstractSummary: 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.imageTEM 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

AbstractSummary: 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).imageConfocal 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

AbstractSummary: 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.imageSEM 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

AbstractSummary: 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.imageSynthesis 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

AbstractWe 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

AbstractDecisions 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

AbstractThe 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

AbstractCurrent 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

AbstractDystonia 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

AbstractWe 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