bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel moisture‐curable epoxy resins and their characterization
Authors: Okuhira Hiroyuki , Kii Tomoya , Ochi Mitsukazu , Takeyama Hidekazu
Published: April 2003

The shelf‐life stability and curability of a moisture‐curable epoxy resin system were evaluated with ketimines, which were used as moisture‐latent hardeners and were derived from different kinds of ketones as protective groups. Both the shelf‐life stability and curability of the compounds were mainly influenced by the steric hindrance of the ketimines. The theoretical results calculated by MOPAC showed good agreement with the experimental results. Methyl i‐propyl ketone and methyl t‐butyl ketone, having a narrow space (<4.2 Å) around ketimine N and a wide space (>3.7 Å) around ketimine C, were demonstrated to be the optimum ketones for the ketimines. The lap shear strength, with respect to the adhesive properties of the ketimines, was higher with a large‐volume ketone than with a small‐volume ketone as the protective group. This was due to the higher reaction conversion of the epoxide for the system. In addition, the large plasticizing effect of the large ketone volume could lead to a large relaxation of the stress generated at the bonding interface. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 91–95, 2003
Electrically conducting polyaniline‐PBMA composite films obtained by extrusion
Authors: Castillo‐Ortega M. M. , Castillo‐Castro T. Del , Encinas J. C. , Perez‐Tello M. , De Paoli Marco‐A. , Olayo R.
Published: April 2003

Poly(n‐butyl methacrylate) (PBMA)–polyaniline (PANI) composite films were obtained by extrusion by use of two methods: the first method consisted of polymerizing a thin layer of PANI, with Cl− as dopant, on the extruded film of PBMA; the second method was based on blends of PBMA and PANI produced by the extrusion of the two polymers by using dodecylbenzene sulfonic acid (DBSA) as dopant. The thermal properties, electrical conductivity, and morphology of the composite films obtained were measured. The sensitivity of the composites films as detectors of hydrogen peroxide and ammonia was evaluated. The change in the electrical resistance on exposure to different aqueous solutions of these components shows a linear behavior. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 179–183, 2003
Fine‐needle aspiration cytology in lesions related to ornamental body procedures (skin tattooing, intraoral piercing) and recreational use of drugs (intranasal route)
Authors: Zaharopoulos Paul
Published: April 2003

Body adornment through tattooing and body piercing and the use of recreational drugs are on the increase, producing a variety of secondary lesions, the etiology of which often remains undetected, as the medical community is not yet aware of the extent of the morbidity of such procedures and practices. Three cases are presented, which underscore the problem and also the role that fine‐needle aspiration (FNA) can play in clarifying the etiology of such lesions. Two of these cases were lymphadenopathies, one secondary to tattooing and the other to tongue piercing, while the third was a deep intranasal lesion, which in all probability had resulted from intranasal use of recreational drugs. Although the clinical diagnosis of these lesions was problematic, the FNA performed by a pathologist, by associating the cytologic findings with the corresponding clinical setting, was quite indicative of their relation to the aforementioned procedures or practices. Diagn. Cytopathol. 2003;28:258–263. © 2003 Wiley‐Liss, Inc.
New amidino‐benzimidazolyl thiophenes: Synthesis and photochemical synthesis
Authors: Starčević Kristina , Boykin David W. , Karminski‐Zamola Grace
Published: April 2003

New amidino‐benzimidazolyl‐substituted bis‐1,2‐(2‐thienyl)ethenes (4, 5, and 6) and benzo[1,2‐ b:4,3‐ b′]dithiophenes (8, 9, and 10) were prepared by the condensation of amidino‐substituted o‐phenylene diamines with corresponding dialdehydes (3 and 7). All prepared amidino‐benzimidazolyl‐substituted compounds are of particular interest, because they can serve as intercalators or groove binders on DNA in anticancer therapy. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:218–222, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10126
Reaction of nitrile oxides with vinylphosphonate: A facile, regioselective approach to 5‐phosphonyl‐4, 5‐dihydroisoxazoles
Authors: Ye Yong , Zheng Yu , Xu Guo‐Yan , Liu Lun‐Zu
Published: April 2003

A series of 5‐phosphonyl‐4,5‐dihydroisoxazoles was synthesized from nitrile oxides and diethylvinylphosphonate under very mild conditions in good yields. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:254–257, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10136
C‐phosphorylated pyrrolylcarbaldehydes
Authors: Ivonin Sergey P. , Tolmachev Andrew A. , Terikovska Tatyana E. , Anishchenko Andrew A. , Chaikovskaya Alexandra A. , Pinchuk Alexander M.
Published: April 2003

Application of N,N‐dimethylhydrazone protective group for synthesis of C‐phosphorylated aldehydes of the pyrrole series was studied. Removal of the hydrazone protection in monophosphorylated pyrrolylcarbaldehyde hydrazones occurs smoothly, while in biphosphorylated derivatives it results in nitrile formation. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:258–261, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10137
Asymmetric borane reduction of prochiral ketones catalyzed by phosphinamides prepared from L‐serine
Authors: Li Kang‐Ying , Zhou Zheng‐Hong , Wang Li‐Xin , Zhao Guo‐Feng , Choi Michael C. K. , Zhou Qi‐Lin , Tang Chu‐Chi
Published: April 2003

Synthesis of several new chiral phosphinamide catalysts with a proximal hydroxyl group from L‐serine was described. These compounds have been successfully used in the asymmetric catalytic borane reduction of prochiral ketones. The optically active secondary alcohols were obtained with an enantiomeric excess (ee) up to 81% and excellent yields. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:288–291, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10145
Effects of unilateral pallidotomy on voluntary movement, and simple and choice reaction times in Parkinson's disease
Authors: Hayashi Ryoichi , Hashimoto Takao , Tada Tsuyoshi , Ikeda Shu‐ichi
Published: April 2003

We studied the effects of unilateral pallidotomy on motor execution and reaction times in patients with moderately advanced Parkinson's disease (PD). Twelve consecutive patients (7 men, 5 women; all right‐handed) underwent left‐side microelectrode‐guided pallidotomy. In addition to clinical rating, reaction time (RT) tests and repetitive movements of the contralesional hand/arm were carried out at baseline and 2 to 3 months after surgery while patients were on optimal medical regimens (on period). The initiation time in both simple reaction time (SRT) and choice reaction time (CRT) improved significantly after pallidotomy (P < 0.05), whereas no effect was observed on the choice processing time, which was calculated by subtracting the mean value of the onset of SRT from that of CRT. Pallidotomy resulted in significant improvement of repetitive movements such as hand pronation/supination and finger‐tapping (P < 0.002, P < 0.005, respectively). Improvements in RT tests and repetitive movements suggest that pallidotomy may enhance attention and motor function. These effects are probably mediated through the pallido‐thalamic‐cortical neural circuitry. © 2003 Movement Disorder Society
Alternating leg muscle activation during sleep and arousals: A new sleep‐related motor phenomenon?
Authors: Chervin Ronald D. , Consens Flavia B. , Kutluay Ekrem
Published: April 2003

We describe a quickly alternating pattern of anterior tibialis activation, recorded during nocturnal polysomnography in 16 patients. Polysomnography, usually for sleep‐disordered breathing, included surface electromyograms over the anterior tibialis of each leg. Cases were identified from approximately 1,500 studies reviewed in the course of standard clinical care. Patients were 12 men and 4 women (mean age, 41 ± 15 years; range, 12–70 years). Brief activation of the anterior tibialis in one leg alternated with similar activation in the other leg. Activations occurred at a frequency of approximately 1 to 2 Hz, each lasted between 0.1 and 0.5 seconds, and sequences of alternating activations usually lasted between several and 20 seconds. The phenomenon occurred in all sleep stages but particularly during arousals. Ten of the 16 patients had periodic leg movements during sleep at a rate ≥ 5.0 per hour, and 12 of the 16 patients were taking antidepressant medication. Alternating leg muscle activation (ALMA) during sleep, at this relatively high frequency, may be a newly described phenomenon. We speculate that ALMA could represent transient facilitation of a spinal central pattern generator for locomotion, perhaps due to serotonergic effects of antidepressant medication. © 2003 Movement Disorder Society
Trigemino‐facial inhibitory reflexes in idiopathic hemifacial spasm
Authors: Pavesi Giovanni , Cattaneo Luigi , Chierici Elisabetta , Mancia Domenico
Published: April 2003

We investigated trigemino‐facial excitatory and inhibitory responses in perioral muscles in hemifacial spasm (HFS). We examined 15 patients affected with idiopathic HFS and 8 healthy controls. Five patients had spasms mostly limited to the periocular region and 10 had spasms also involving the perioral muscles. Responses were recorded from the resting orbicularis oculi (OOc), levator labii superioris (LLS) and orbicularis oris (OOr) muscles, after supraorbital (SO) nerve stimulation and during isolated voluntary contraction of LLS muscle. Eight patients showed complete or partial preservation of the late silent period (SP2) in activated LLS muscle. The remaining 7 patients showed absence of SP2. Early and late excitatory responses were variably present in LLS muscle at rest. Patients with HFS clinically restricted to periocular muscles had at least partial preservation of the SP2. In conclusion, in HFS patients inhibitory trigemino‐facial reflexes are impaired and excitatory trigemino‐facial responses are elicited in perioral muscles. These two phenomena seem to develop independently; the degree of trigemino‐facial reflex impairment parallels the extension of involuntary movements to the lower facial muscles. © 2003 Movement Disorder Society
Indonesian tea mistletoe (Scurrula oortiana) stem extract increases tumour cell sensitivity to tumour necrosis factor alpha (TNFα)
Authors: Murwani Retno
Published: April 2003

The water extract of Indonesian tea mistletoe, Scurrula oortiana (‘benalu teh’), has been used for generations to treat tumours, however, little is known of its biological action. In the present study the stem and leaf extracts of S. oortiana were investigated for their modulation of tumour cell sensitivity toward TNFα, a potent anti‐tumour cytokine. WEHI‐164 cells which are known to be sensitive to TNFα, were used as a model. The assay results showed that either the stem or leaf extract of S. oortiana increased the sensitivity or susceptibility of WEHI‐164 cells to TNFα as shown by decreases in LD50 values in the TNFα sensitivity assay. The stem extract showed a greater increase than the leaf extract, increasing the sensitivity more than 160 times compared with the normal untreated tumour cells. This study showed for the ﬁrst time that water extracts of S. oortiana were signiﬁcantly cytotoxic to the WEHI‐164 tumour cell line and increased tumour cell sensitivity to TNFα mediated lysis. Copyright © 2003 John Wiley & Sons, Ltd.
Essential oil composition and antifungal activity of Foeniculum vulgare Mill. obtained by different distillation conditions
Authors: Mimica‐Dukić N. , Kujundžić S. , Soković M. , Couladis M.
Published: April 2003

The inﬂuence of different hydrodistillation conditions was evaluated from the standpoint of essential oil yield, chemical composition and antifungal activity from seeds of Foeniculum vulgare Mill. Three hydrodistillation conditions were considered. The main constituents of the oils were: (E)‐anethole (72.27%–74.18%), fenchone (11.32%–16.35%) and methyl chavicol (3.78%–5.29%). The method of distillation signiﬁcantly effected the essential oil yield and quantitative composition, although the antifungal activity of the oils against some fungi was only slightly altered. Copyright © 2003 John Wiley & Sons, Ltd.
Butanolides from Machilus thunbergii and their inhibitory activity on nitric oxide synthesis in activated macrophages
Authors: Kim Nam Yi , Ryu Jae‐Ha
Published: April 2003

In activated macrophages the inducible form of nitric oxide synthase (iNOS) generates high amounts of the toxic mediator, nitric oxide (NO), that contributes to the circulatory failure associated with septic shock. Three butanolides were isolated from Machilus thunbergii as active principles which inhibit the production of NO in lipopolysaccharide‐activated RAW 264.7 cells, and their structures were identiﬁed as litsenolide A2 (1), B1 (2) and B2 (3). They showed dose‐dependent inhibition of NO syntheses and the IC50s were 3.36, 3.70 and 6.19 µm, respectively. These new inhibitors of iNOS may have potential in the treatment of endotoxaemia and inﬂammation accompanied by the overproduction of NO. Copyright © 2003 John Wiley & Sons, Ltd.
Analysis of the N‐linked oligosaccharides of human C1s using electrospray ionisation mass spectrometry
Authors: Petillot Yves , Thibault Pierre , Thielens Nicole M. , Rossi Véronique , Lacroix Monique , Coddeville Bernadette , Spik Geneviève , Schumaker Verne N. , Gagnon Jean , Arlaud Gérard J.
Published: April 2003

Information on the structures of the oligosaccharides linked to Asn residues 159 and 391 of the human complement protease Cs was obtained using mass spectrometric and monosaccharide analyses. Asn159 is linked to a complex‐type biantennary, bisialylated oligosaccharide NeuAc2 Gal2 GlcNAc4 Man3 (molecular mass = 2206 ± 1). Asn391 is occupied by either a biantennary, bisialylated oligosaccharide, or a triantennary, trisialylated species NeuAc3 Gal3 GlcNAc5 Man3 (molecular mass = 2861 ± 1), or a fucosylated triantennary, trisialylated species NeuAc3 Ga13 GIcNAc5 Man3 Fucl (molecular mass = 3007 ± 1), in relative proportions of approximately 1:1:1. The carbohydrate heterogeneity at Asn391 gives rise to three major types of Cs molecules of molecular masses 79,318 ± 8 (A), 79,971 ± 8 (B), and 80,131 ± 8 (C), with an average mass of 79,807 ± 8. A minor modification, yielding an extra mass of 132 ± 2, is also detected within positions 1–153.
Wortmannin inhibits carcinogen‐stimulated phosphorylation of ethanolamine and choline
Authors: Kiss Zoltan , Tomono Masahiro
Published: April 2003

We have previously reported that in C3H/10T1/2 fibroblasts the environmental carcinogen 7,12‐dimethyl‐benz[a]anthracene (DMBA) stimulated phosphorylation of ethanolamine (Etn). Here we show that in these fibroblasts DMBA also stimulates phosphorylation of choline (Cho). Wortmannin (50–200 nM), an established inhibitor of phosphatidylinositol‐3‐kinase (PI3K), significantly inhibited DMBA‐induced phosphorylation of both Etn and Cho. Wortmannin also inhibited the effect of insulin, a major activator of PI3K, on DNA synthesis. However, insulin had no effect on the phosphorylation of Etn and Cho. These data suggest that a carcinogen‐induced kinase phosphorylates both Etn and Cho, and that the inhibitory effect of wortmannin on Etn/Cho kinase activity may be unrelated to its inhibitory effect on PI3K activity.
Molecular cloning and functional expression in yeast of a human cAMP‐specific phosphodiesterase subtype (PDE IV‐C)
Authors: Engels Peter , Sullivan Michael , Müller Thomas , Lübbert Hermann
Published: April 2003

We have recently reported increased survival of dopaminergic substantia nigra neurons by inhibition of phosphodiesterase type IV enzymes. As a first step to unravel the involvement of PDE IV subtypes in this process, we isolated phosphodiesterase type IV cDNAs from human substantia nigra. One isolated partial cDNA clone was most homologous to the partially cloned rat and human PDE IV‐C isogene. Distribution analysis revealed that the enzyme is expressed in various tissues but not in cells of the immune system. Isolation of the full‐length human PDE IV‐C isogene cDNA and expression in a PDE‐deficient yeast strain resulted in functional complementation of the yeast heat shock response. Inhibition of the enzymatic activity by rolipram characterized this enzyme as a typical type IV phosphodiesterase.
Characterisation of a synergohymenotropic toxin produced by Staphylococcus intermedius
Authors: Prevost G. , Bouakham T. , Piemont Y. , Monteil H.
Published: April 2003

Staphylococcal synergohymenotropic (SHT) toxins damage membranes of host defence cells and erythrocytes by the synergy of two secreted and non‐associated proteins: class S and class F components. Whereas Panton‐Valentine leucocidin (PVL), γ‐hemolysin and Luk‐M from Staphylococcus aureus are members of this toxin family, a new bi‐component toxin (LukS‐I + LukF‐I) from Staphylococcus intermedius, a pathogen for small animals, was characterised and sequenced. It is encoded as a luk‐I operon by two cotranscribed genes, like PVL. LukS‐I + LukF‐I shares a strong leukotoxicity of various PMNs, but only slight haemolytic properties on rabbit erythrocytes. When intradermally injected into rabbit skin, a 100 ng dose caused acute inflammatory reaction leading to tissue necrosis. The new SHT seemed to be largely distributed among various Staphylococcus intermedius strains.
Conformational dynamics monitored by His‐179 and His‐200 of isolated thermophilic F1‐ATPase β subunit which reside at the entrance of the ‘conical tunnel’ in holoenzyme
Authors: Tozawa Kaeko , Sekino Nobuaki , Soga Masanobu , Yagi Hiromasa , Yoshida Masasuke , Akutsu Hideo
Published: April 2003

When monitored by 1H NMR at various pH values, most of the C‐2 proton signals from 12 His residues of the isolated β subunit of thermophilic F1‐ATPase (TF1) could be separately observed. Two of them were assigned to His‐179 and His‐200 which reside at the entrance of a ‘conial tunnel’ to reach catalytic site in the crystal structure of F1‐ATPase. His‐200 gave doublet, suggesting that this region is not a rigid α‐helix in the isolated β subunit. The binding of Mg · AMP‐PNP changed the chemical shifts of His‐179 and His‐200 significantly. Although His‐119 located at the opposite side of the conical tunnel was not affected by the nucleotide‐binding, it contributed to the stability of β subunit and the efficiency of the catalysis of the holoenzyme.
Sedimentation and immunological analyses of GLUT4 and α2‐Na,K‐ATPase subunit‐containing vesicles from rat skeletal muscle: evidence for segregation
Authors: Aledo J.Carlos , Hundal Harinder S.
Published: April 2003

In skeletal muscle insulin induces the translocation of both the GLUT4 glucose transporter and the α2 subunit of the Na,K‐ATPase from an intracellular membrane (IM) compartment to the plasma membrane (PM). Fractionation studies of rat skeletal muscle using a discontinuous sucrose gradient have indicated that the insulin‐induced loss of both proteins occurs from a fraction containing intracellular membranes (IM) of common density. This raises the possibility that both proteins may be colocalized in a single intracellular compartment or are present in separate membrane vesicles that are of similar buoyant density. In this study we report that membrane vesicles from the insulin‐responsive IM fraction can in fact be separated on the basis of differences in their sedimentation velocities; immunoblot analyses of fractions collected from a sucrose velocity gradient revealed the presence of two separate peaks for GLUT4 and the α2 subunit of the Na,K‐ATPase. One of these peaks representing a fast sedimenting population of vesicles (with a sedimentation coefficient of 2697 ± 57 S) reacted against antibodies to the α2 subunit of the Na,K‐ATPase, whereas, the second peak contained a population of much slower sedimenting vesicles (with a sedimentation coefficient of 209 ± 4 S) were practically devoid of the α2‐subunit. By contrast, the slow sedimenting vesicles were enriched by ∼32‐fold in GLUT4 relative to the starting IM fraction when the fractional protein content was taken into account. Immunoprecipitation of GLUT4‐containing vesicles from the insulin‐sensitive IM fraction revealed that no immunoreactivity towards either the α2 or the β1 subunits of the Na,K‐ATPase could be observed, signifying that the insulin‐responsive subunits of the Na,K‐ATPase and GLUT4 were present in different membrane vesicles and that it was unlikely, therefore, that the insulin‐induced redistribution of these proteins to the PM occurs from a common intracellular pool.
15N labeling method of peptides using a thioredoxin gene fusion expression system: an application to ACTH‐(1–24)
Authors: Uegaki Koichi , Nemoto Nobuaki , Shimizu Masato , Wada Takashi , Kyogoku Yoshimasa , Kobayashi Yuji
Published: April 2003

For structure analysis of peptides by multinuclear NMR, stable isotope‐labeled samples are required. A direct over‐expression system by E. coli cells does not work for that purpose because of rapid degradation of the peptides and/or the mRNA in host cells. We here developed an over‐expression system by means of thioredoxin gene fusion system. The fused protein composed of thioredoxin and the objective peptide was expressed in E. coli and then the peptide part was released by enterokinase. This system was successfully applied for the production of 15N‐labeled human adrenocorticotropic hormone fragment (ACTH‐(1‐24)) as needed for multinuclear NMR analysis.
Elevated cPLA2 levels as a mechanism by which the p70 TNF and p75 NGF receptors enhance apoptosis
Authors: MacEwan David J.
Published: April 2003

The 70‐kDa TNF cell surface receptor (p70TNFR) and the related 75‐kDa nerve growth factor (NGF) receptor (p75NGFR) can enhance cell death. Expression of p70TNFR or p75NGFR in HeLa cells resulted in enhanced TNF‐induced apoptotic cell death with a corresponding elevation of cytosolic phospholipase A2 (cPLA2) levels. This response was apparent by 24 h, did not occur with NGF treatment or when vector or TrkA NGFR were expressed and was reversed by dexamethasone pretreatment. These findings reveal a novel mechanism by which the p70TNFR and p75NGFR achieve enhanced TNFR‐mediated programmed cell death by elevating cPLA2 levels.
Stimulation of human peripheral blood lymphocytes by bioactive peptides derived from bovine milk proteins
Authors: Kayser Holger , Meisel Hans
Published: April 2003

The in vitro modulation of the proliferation of human peripheral blood lymphocytes of different synthetic peptides derived from milk proteins was investigated. Therefore, proliferation changes were followed up after incorporation of BrdU into the DNA, and the influence on protein biosynthesis was measured using the [3H]leucine incorporation test. Tyr‐Gly and Tyr‐Gly‐Gly significantly enhanced (maximal 90 and 35%, respectively) the proliferation of PBL. For β‐casomorphin‐7 and β‐casokinin‐10, lymphocyte proliferation was suppressed at lower concentrations, but stimulated at higher concentrations (≥10−7 mol/l). Protein synthesis was stimulated (maxima at 25%) only with Tyr‐Gly and Tyr‐Gly‐Gly. The findings point to a need for further studies on the possible function of peptides derived from milk proteins as orally bioavailable immunopotentiatory compounds.
Reversible hydrogenase of Anabaena variabilis ATCC 29413: catalytic properties and characterization of redox centres
Authors: Serebryakova Larissa T. , Medina Milagros , Zorin Nikolay A. , Gogotov Ivan N. , Cammack Richard
Published: April 2003

The catalytic and spectroscopic properties of the reversible hydrogenase from the cyanobacterium Anabaena variabilis have been examined. The hydrogenase required reductive activation in order to elicit hydrogen‐oxidation activity. Carbon monoxide was a weak (K

i
= 35 μM), reversible and competitive inhibitor. A flavin with the chromatographic properties of FMN, and nickel were detected in the purified enzyme. A. variabilis hydrogenase exhibited electron paramagnetic resonance (EPR) spectra in its hydrogen‐reduced state, indicative of [2Fe‐2S] and [4Fe‐4S] clusters. Although no EPR signals due to nickel were detected, the results are consistent with the enzyme being a flavin‐containing hydrogenase of the nickel‐iron type.
Hydrogen peroxide and sequence‐specific DNA damage in human cells
Authors: Burdon R.H. , Gill Vera , Boyd Patricia A. , Rahim Raha Abdul
Published: April 2003

Exposure of HeLa cells in monolayer culture to increasing concentrations of exogenously added H2O2 causes damage to cellular DNA. When the DNA is subsequently isolated from the non‐apoptotic cells remaining in such cultures, evidence was obtained to suggest that the DNA damage elicited in intact cells was non‐random and that certain nucleotide sequences associated with, or related to, the genes for heat shock protein 60 and catalase were more susceptible to damage than others. In contrast, these particular sequences were not specifically susceptible to damage when naked human DNA was exposed directly to H2O2 in vitro. On an overall comparative basis, sequences in the genes encoding catalase, α‐1 antitrypsin and β‐actin appear more vulnerable to H2O2 in vivo, than sequences in H‐ras and the p53 gene which seem surprisingly resistant.
Tyrosine phosphorylation and subcellular redistribution of p125 ras guanosine triphosphatase‐activating protein in human neutrophils stimulated with FMLP
Authors: Dusi Stefano , Donini Marta , Wientjes Frans , Rossi Filippo
Published: April 2003

In this paper, we show that the p125 ras guanosine triphosphatase‐activating protein (p125 GAP) is present in the cytosol of human neutrophils and is transiently tyrosine phosphorylated and translocated to the membranes upon cell activation with formyl‐methionyl‐leucyl‐phenylalanine (FMLP). When concanavalin A (ConA) or phorbol 12‐myristate 13‐acetate (PMA), which both induced a long‐lasting respiratory burst, were used as stimuli, tyrosine phosphorylation and translocation of p125 GAP did not occur.
Immunohistochemical analysis of presenilin‐1 expression in the mouse brain
Authors: Moussaoui S. , Czech C. , Pradier L. , Blanchard V. , Bonici B. , Gohin M. , Imperato A. , Revah F.
Published: April 2003

At least 22 different mutations associated with early‐onset familial Alzheimer's disease (AD) in various kindreds have been reported to occur in a recently identified gene on chromosome 14, presenilin 1 (PS‐1) (Sherrington et al. (1995) Nature 375, 754–760 [1] and reviewed by Van Broeckhoven (1995) Nat. Genet. 11, 230–231 [2]). In order to study the localization of PS‐1 in the brain, we raised a polyclonal antiserum specific to a fragment of the predicted protein sequence of PS‐1. PS‐1 immunostaining was found intracellularly, in the perikaria of discrete cells, mostly neurons, appearing as thick granules, resembling large‐size vesicles. These granules were located in the periphery of cell bodies and extended into dendrites and neurites. PS‐1 expression was found to be broadly distributed throughout the mouse brain, not only in structures involved in AD pathology, but also in structures unaltered by this disease.
Excess formation of lysophosphatidic acid with age inhibits myristic acid‐induced superoxide anion generation in intact human neutrophils
Authors: Ito Yoshikazu , Ponnappan Usha , Lipschitz David A.
Published: April 2003

A superoxide anion generation rate upon exposure to myristate of 1.93 ± 0.34 nmol/min/106 cells in neutrophils from elderly human donors was significantly less than a value of 3.02 ± 0.48 nmol/min/106 neutrophils from young donors. Myristate activation resulted in equal increases of AA in both the young and the old indicating no effect of aging on the PLA2 pathway to response. By contrast, the PLD‐induced generation of PA was significantly higher in the old than in the young. In addition, myristate induced a significant age‐related enhancement in LPA generation, in the old but not in the young. The mass of LPA generated following activation was 3.5 nmol/ 2.5 × 107cells/ml in the young while in the old it averaged 7.0 nmol/2.5 × 107 cells/ml. The inhibitory effects of LPA may explain the age‐related impaired ability to generate superoxide anion following activation by myristate.
Comparative study on the phosphotyrosine motifs of different cytokine receptors involved in STAT5 activation
Authors: May Petra , Gerhartz Claudia , Heesel Birgit , Welte Thomas , Doppler Wolfgang , Graeve Lutz , Horn Friedemann , Heinrich Peter C.
Published: April 2003

Several cytokines and growth factors activate transcription of their target genes via the JAK/STAT signalling pathway. It has been shown that the interaction between SH2 domains of STAT factors and receptor phosphotyrosine residues plays an essential role in the specific recruitment of STATs. For STAT5, however, the importance of receptor tyrosines is still controversial. Using a chimeric receptor system in COS‐7 cells, we studied the activation of STAT5 through the interleukin‐6 signal transducer gp130. In contrast to previous reports, we did not detect gp130‐mediated STAT5 activation. However, STAT5 activation was achieved when tyrosine motifs of other cytokine receptors were fused to the membrane‐proximal part of gp130. The comparison of the relative potency of different tyrosine motifs revealed that hydrophobic amino acids, preferentially leucine, in positions +1 and +3, and an aspartate residue in position ‐1 or ‐2 with respect to the tyrosine are likely to be required for efficient STAT5 recruitment. In summary, we show here for the first time that phosphotyrosine motifs can confer the ability to activate STAT5 to a heterologous receptor.
In vitro synthesized SV40 cRNA is trans‐spliced after microinjection into the nuclei of mammalian cells
Authors: Eul J. , Graessmann M. , Graessmann A.
Published: April 2003

We present for the first time experimental evidence that in vitro synthesized RNA (cRNA) is trans‐spliced after microinjection into the nuclei of mammalian tissue culture cells. The template used for cRNA synthesis was the early SV40 BstXI/BamHI DNA fragment. This DNA fragment encodes exclusively for the second T‐antigen exon and contains the intact small t‐antigen intron. To generate the corresponding mRNA (t1‐mRNA) by trans‐splicing, the cells utilize a 5′ cryptic splice site located within the second T‐antigen exon of one cRNA molecule which is spliced to the small t‐antigen 3′ splice site of another cRNA molecule. Formation of the T1‐mRNA by trans‐splicing was confirmed by RT‐PCR analysis and DNA sequencing. Efficient trans‐splicing required that competitive small t‐antigen cis‐splicing be inhibited by deletion of the small t‐antigen 5′ splice site. The T1‐mRNA was not generated when the cryptic 5′ splice site was mutated.
DNA methylation patterns in tumors derived from F9 cells resemble methylation at the blastula stage
Authors: Yeivin Agnes , Levine Alex , Razin Aharon
Published: April 2003

We show here that the genome of F9 teratocarcinoma cells growing in culture is heavily methylated but undergoes massive demethylation in tumors derived by subcutaneous injection of the cells. This demethylation occurs primarily in single copy gene sequences. As a result imprinted genes acquire their characteristic monoallelic methylation patterns while non‐imprinted genes undergo demethylation. The overall methylation pattern in the tumors resembles the pattern observed in the mouse preimplantation embryo. The F9 cells in the tumors apparently recognize imprinted genes, distinguish them from non‐imprinted genes and change the methylation of both gene classes to the pattern which characterizes the embryo. These cells therefore have the potential of providing an abundant source of protein factors involved in establishing the methylation pattern during embryo development.
Dictyostelium cytosolic fucosyltransferase synthesizes H type 1 trisaccharide in vitro
Authors: Trinchera Marco , Bozzaro Salvatore
Published: April 2003

A fucosyltransferase activity has been detected using lacto‐N‐biose I as acceptor in the lower eukaryote Dictyostelium discoideum. This transferase requires divalent cations and is inhibited by N‐ethylmaleimide and detergent treatment. Apparent calculated K

m
values for GDP‐Fuc and lacto‐N‐biose I are 1.27 μM and 2.80 mM, respectively. The activity is quantitatively recovered in the supernatant after centrifugation at 100 000 × g for 1 h. The reaction product, as determined by gel permeation chromatography, sensitivity to fucosidases, and analysis of partially methylated derivatives, is Fucα1‐2Galβ1‐3GlcNAc (H type 1 trisaccharide).
Amphiphilic helix is essential for the activity of brain injury‐derived neurotrophic peptide (BINP)
Authors: Hama Tokiko , Murayama Miyuki , Kato Rika , Ohtake Atsuko , Sato Kazuki
Published: April 2003

To study the structure‐activity relationships of brain injury‐derived neurotrophic peptide (BINP), 12 analogs were synthesized by replacing each amino acid residue with Gly. BINP showed CD spectra typical of an α‐helical conformation in TFE solution which mimics the membrane environment. In the α‐helical conformation, BINP showed an amphiphilic profile. Neurotrophic activities of BINP and its analogs were estimated from the effects on supporting septal cholinergic neurons and on rescuing hippocampal neurons from injury caused by glutamate. Both assays showed that the residues on the hydrophobic side of the amphiphilic helix were essential for the neurotrophic activity.
A systemic antiviral resistance‐inducing protein isolated from Clerodendrum inerme Gaertn. is a polynucleotide:adenosine glycosidase (ribosome‐inactivating protein)
Authors: Olivieri Fabiola , Prasad Vivek , Valbonesi Paola , Srivastava Shalini , Ghosal-Chowdhury Papiya , Barbieri Luigi , Bolognesi Andrea , Stirpe Fiorenzo
Published: April 2003

Two systemic antiviral resistance‐inducing proteins, CIP‐29 and CIP‐34, isolated from Clerodendrum inerme Gaertn. leaves, were tested for ribosome‐inactivating properties. It was found that CIP‐29 has the characteristics of a polynucleotide: adenosine glycosidase (ribosome‐inactivating protein), in that it inhibits protein synthesis both in cell‐free systems and, at higher concentrations, in cells, and releases adenine from ribosomes, RNA, poly(A) and DNA. As compared with other known RIPs, CIP‐29 deadenylates DNA at a high rate, and induces systemic antiviral resistance in susceptible plants.
Gene of rat Ca2+/calmodulin‐dependent protein kinase II α isoform — its cloning and whole structure
Authors: Nishioka Nobuhiro , Shiojiri Masatoshi , Kadota Shiori , Morinaga Hisayo , Kuwahara Jun , Arakawa Toshiya , Yamamoto Shozo , Yamauchi Takashi
Published: April 2003

The gene encoding the α isoform of rat Ca2+/ calmodulin‐dependent protein kinase II was cloned, and its exon‐intron organization was analyzed. The coding region of cDNA consists of 18 exons spanning more than 50 kilobase pairs. Each of the discrete functional units, such as the ATP‐binding site, the autophosphorylation site responsible for Ca2+‐independent activity, the calmodulin‐binding site, and link structure is encoded by a single exon. The largest and smallest exons consist of 229 and 41 base pairs, respectively. All splice junction sequences flanking the introns conform to the consensus splice junction sequence and the GT‐AG splice rule.
Dityrosine bridge formation and thyroid hormone synthesis are tightly linked and are both dependent on N‐glycans
Authors: Baudry Nathalie , Lejeune Pierre-Jean , Niccoli Patricia , Vinet Liliane , Carayon Pierre , Mallet Bernard
Published: April 2003

Formation of dityrosine bridges is a ubiquitous process mainly attributed to oxidative stress leading to protein degradation and cellular damages. Here we show that dityrosine formation is involved in a physiological process, thyroid hormone synthesis, and is strictly dependent on structural characteristics, namely N‐glycans, presented by the protein acting as the prothyroid hormone. We used two isoforms of the N‐terminal thyroid hormone forming domain (NTD) of human thyroglobulin: one without N‐glycan (19 kDa isoform) and the other with high mannose type structures (25 kDa isoform). Both isoforms were able to form iodotyrosines after in vitro iodination. However, iodotyrosine coupling to form thyroxine did not occur with the unglycosylated 19 kDa NTD. In contrast, the 25 kDa isoform formed thyroxine. Strikingly, thyroxine synthesis was accompanied by dimerization of the 25 kDa isoform and formation of a dityrosine bridge; none of this was observed with the 19 kDa isoform. Taken as a whole, our results indicate that dimerization through dityrosine bridging accompanies and could have a role in thyroid hormone synthesis.
Carrier‐mediated transport controls hydroxyproline catabolism in heart mitochondria from spontaneously hypertensive rat
Authors: Atlante Anna , Seccia Teresa M. , Marra Ersilia , Minervini Giuseppe M. , Vulpis Vito , Pirrelli Anna , Passarella Salvatore
Published: April 2003

In this study we have investigated hydroxyproline transport in rat heart mitochondria and, in particular, in heart left ventricle mitochondria isolated from both spontaneously hypertensive and Wistar‐Kyoto rats. Hydroxyproline uptake by mitochondria, where its catabolism takes place, occurs via a carrier‐mediated process as demonstrated by the occurrence of both saturation kinetics and the inhibition shown by phenylsuccinate and the thiol reagent mersalyl. In any case, hydroxyproline transport was found to limit the rate of mitochondrial hydroxyproline catabolism. A significant change in V
max and K
m values was found in mitochondria from hypertensive/hypertrophied rats in which the K
m value decreases and the V
max value increases with respect to normotensive rats, thus accounting for the increase of hydroxyproline metabolism due to its increased concentration in a hypertrophic/hypertensive state.
Developmental effects of early postnatal treatment of rats with prochlorperazine
Authors: Rech R. H. , Borsini F. , Samanin R.
Published: April 2003

This study examined effects of neonatal prochlorperazine in rats tested as adults in a variety of behaviors. The drug exposure impaired open field behavior during treatment neonatally. However, no differences in open field behavior were observed in adulthood. Adult females that had received drug were less efficient in obtaining food reinforcement in a conditioned maze performance than were respective controls and showed a slight increase in motor activity during accommodation. d‐Amphetamine‐induced motor activity was greater in both treated males and females relative to respective controls. Spaced trials in shuttle‐box avoidance uncovered an avoidance decrement in the treated females only. This drug treatment appears to cause subtle changes in brain development in the rat.
Effects of changes in neonatal thyroid status on the development of neuropeptide systems in the rat brain
Authors: Woodhams P.L. , McGovern J. , McGregor G.P. , O'Shaughnessey D.J. , Ghatei M.A. , Blank M.A. , Adrian T.H. , Lee Y. , Polak J.M. , Bloom S.R. , Balázs R.
Published: April 2003

The effects of neonatal thyroid deficiency or hyperthyroidism on the development of neurones containing certain neuropeptides was examined in the brains of rats killed at two weeks of age. Five brain areas were dissected and extracted for radioimmunoassay measurement of vasoactive intestinal polypeptide (VIP), somatostatin, cholecystokinin octapeptide (CCK), substance P and neurotensin, whilst corresponding immunocytochemical data were obtained from a quantitative morphological analysis of cell bodies in the cingulate cortex. The two methods of analysis did not always agree, but in hypothyroidism both the concentration of VIP and the number of cells containing VIP‐like immunoreactivity were significantly decreased in the anterior and posterior cingulate cortex. In contrast to these effects on the late maturing VIP neurones, the earlier developing somatostatin system was relatively unaffected, whilst neuropeptides localized in cortical fibres rather than cell bodies (such as substance P and neurotensin) were found by radioimmunoassay to be elevated. Hyperthyroidism had less marked effects than neonatal thyroidectomy, although the concentration of CCK (but not the number of immunostained cells) was significantly increased in the cingulate cortex. Radioimmunoassay results from three subcortical areas showed a decrease in VIP concentration in the hypothyroid hypothalamus, and in hyperthyroidism significant elevations of VIP in the basal ganglia, somatostatin in the hypothalamus and CCK in the hippocampus. It appears that in the brain areas studied thyroid disorders result in dis‐synchronous shifts in the developmental patterns of the different neuropeptides, and that the effects of thyroid hormone on peptides as on other transmitters are critically dependent on the developmental profile of the system in question.
Ornithine decarboxylase and polyamines in developing rat brain and heart: Effects of perinatal hypothyroidism
Authors: Slotkin Theodore A. , Johnson Anne , Whitmore William L. , Slepetis Ruta J.
Published: April 2003

Hypothyroidism induced by perinatal administration of propylthiouracil (PTU) had profound effects on growth of the heart, with major organ weight deficits persisting well beyond the termination of drug treatment. These effects were preceded by disruption of the developmental patterns of cardiac ornithine decarboxylase (ODC) and the polyamines, which are thought to be intracellular modulators of cellular maturation. Activity of cardiac ODC was depressed in the PTU‐treated group and putrescine and spermidine levels were markedly subnormal. PTU administration also affected brain growth, but much less so than in the heart. The disruption of the brain ODC/polyamine system was also less pronounced, with relatively small degrees of spermidine depletion and a slight elevation of ODC. For both tissues, the biochemical effects of perinatal hypothyroidism were opposite to those found previously for administration of exogenous thyroid hormones. These results support the views that: (1) endogenous thyroid hormones contribute to the maintenance of normal developmental patterns of ODC and the polyamines, and (2) the ODC/polyamine system participates in events modulating subsequent tissue growth.
Effect of paradoxical sleep deprivation on dna synthesis in fetal rat brain
Authors: Grassi‐Zucconi G. , Belia S. , Franciolini F. , Menichini E. , Giuditta A.
Published: April 2003

We have investigated the effect of PS‐D induced in gestating rats by treatment with clomipramine or with the platform technique on the process of DNA synthesis taking place in fetal organs. This parameter was taken as a biochemical index of ongoing cellular proliferation. In brain and, to a minor extent, in liver and kidney the rate of fetal DNA synthesis was markedly increased in both experimental groups. The effect was more prominent in the clomipramine group. PS‐D treatment of gestating rats, notably by the platform technique, left long‐lasting effects in the offspring with regard to organ weight and DNA concentration as well as to learning capacity. It is concluded that the occurrence of PS in gestating rats may exert a significant influence on fetal development.
Effects of NaCl and sultopride on striatal [3H]spiperone binding in neonatal, adult and senescent rats
Authors: Makihata Junko , Nomura Yasuyuki
Published: April 2003

Effects of NaCl, (+)‐and (−)‐sultopride on striatal [3H]spiperone binding was investigated in 7‐day, 70‐day and 2‐year‐old rats. The amount of specific [3H]spiperone binding was the highest at 70 days and the value at adult stage was significantly (P < 0.001) higher than those at 7 days and 2 years. NaCl (100 mM) significantly increased [3H]spiperone binding in neonatal (P < 0.01), adult (P < 0.05) and senescent (P < 0.05) animals. Scatchard analysis showed that the Bmax of low‐affinity [3H]spiperone binding was significantly elevated by 100 mM NaCl compared to the value in control of adult animals. More potent inhibition of (−)‐sultopride for [3H]spiperone binding than that of the (+)‐enantiomer at adult stage was also observed at neonatal and senescent stages. NaCl (100 mM) significantly enhanced inhibitory activities of (+)‐ and (−)‐sultopride at every stage. It is suggested that stabilizing effect of Na+ on dopamine (DA) receptor complexes and increasing effect of Na+ on binding affinity of benzamide to DA2 receptors keep functions through development and aging.
Behavioral effects of phosphatidylserine after perinatal administration in rats
Authors: Drago F. , Continella G. , Alloro M.C. , Presti L. Lo , Scapagnini U.
Published: April 2003

Behavioral effects of the acidic phospholipid phosphatidylserine (PS) were studied in rats after perinatal (prenatal or neonatal) administration. PS was administered to pregnant rats from day 5 of pregnancy. PS liposomes were also injected i.p. to offspring from postnatal days 1–5. PS‐treated rats showed a more precocious onset of neonatal behaviors, and a significant improvement in acquiring avoidance responses when tested at 60 days of age. Behavioral effects of PS may be related to a possible influence on dendritic arborization during perinatal period.
Histochemical study of biogenic monoamines in early (“Prenervous”) and late embryos of sea urchins
Authors: Markova L.N. , Buznikov G.A. , Kovačević N. , Rakić L. , Salimova N.B. , Volina E.V.
Published: April 2003

Treatment of the embryos of sea urchins with glyoxylic acid results in the appearance of luminescence which is indicative of the presence of biogenic monoamines. At the early stages of development (cleavage divisions, blastula, gastrula) the histochemical method reveals a tryptamine‐like substance which is first found in all embryonic cells and later is concentrated mainly in the cells of the primary gut and ciliary bands. At the stages of prism and pluteus there appear neuron‐like cells containing dopamine. The inhibitors of monoamine oxidase and neurotoxins reliably increase the histochemical reaction to monoamines only in late embryos which suggests a change in the properties of monoaminergic systems in the course of embryogenesis.
Development of muscimol binding sites in chick embryo neural retina in vivo and in vitro: Regulatory effects of cyclic AMP
Authors: Madtes Paul , Adler Ruben
Published: April 2003

We report here the development in the chick embryo retina of binding sites for [3H]muscimol, a potent agonist of GABA receptors. In vivo studies were carried out with isolated neural retinas from different stages of development. High‐affinity binding sites were absent before embryonic day (E) 8, but increased conspicuously between E10 and E16. Scatchard analysis indicated that this rise was due to an increase in the number of binding sites. Kinetic parameters of the embryonic binding sites were consistent with those typically found for mature muscimol receptors. Measurements of the low‐affinity binding site showed a relatively similar developmental pattern although a pronounced decrease in binding to the low‐affinity site was observed between E12 and E14. In vitro studies were carried out using glial‐free, purified monolayers of retinal neurons, starting at E8. Cultured retinal neurons showed a developmental pattern for high‐affinity muscimol binding sites resembling that observed in ovo. These binding sites were susceptible to regulation by cyclic AMP analogues. Increases of 100 to 200% in muscimol binding could be induced by a 24 hr treatment with dibutyryl cyclic AMP, 8‐bromo cyclic AMP, or the phosphodiesterase inhibitor IBMX. Scatchard analysis showed that this increase was due to a change in receptor affinity. No effects were found with either butyric acid or with adenosine 5′‐monophosphate. These results raise the possibility that cyclic AMP may be involved in the regulation of components of the GABA system.