bluuebunny/crossref_metadata_2025 huggingface dataset:
Two novel HMW MAP2 variants with four microtubule‐binding repeats and different projection domains
Authors: Langkopf Anja , Guilleminot Jocelyne , Nunez Jacques
Published: July 2002

The brain microtubule‐associated protein MAP2 is composed of two high molecular (MAP2a and b) and one low molecular (MAP2c) weight isoforms. All these forms were thought to contain three repeated microtubule‐binding domains in their C‐terminal region but a MAP2c variant containing four repeats has recently been identified. We report here the existence of two high molecular weight MAP2 isoforms with four microtubule‐binding domains in the sensory neuronal cell line ND 7/23. A stretch of 135 bp is missing in one of these forms suggesting that several HMW MAP2 variants can be produced by alternative splicing.
Covalent anchoring of proteins onto gold‐directed NHS‐terminated self‐assembled monolayers in aqueous buffers: SFM images of clathrin cages and triskelia
Authors: Wagner Peter , Kernen Peter , Hegner Martin , Ungewickell Ernst , Semenza Giorgio
Published: July 2002

N‐Hydroxysuccinimide‐terminated self‐assembled monolayers with linear (CH2)10 chains were prepared on ultraflat Au(111) surfaces from dithiobis(succinimidylundecanoate). These monolayers, which are covalently chemisorbed to gold via thiolate bonds, form a highly reactive amino‐group specific carpet at the liquid—solid interface. Proteins bind to it covalently in aqueous buffers under mild conditions; this provides a (general) procedure for protein immobilization for scanning probe microscopy. Using this technique, we have obtained what we believe are the first scanning force microscopy images of clathrin cages and of their in situ disassembly, yielding typical triskelia under non‐denaturing conditions.
Three‐dimensional structure of a recombinant peroxidase from Coprinus cinereus at 2.6 Å resolution
Authors: Petersen Jens F.W. , Kadziola Anders , Larsen Sine
Published: July 2002

The structure of a recombinant peroxidase from the ink cap, Coprinus cinereus, CiP, is reported to 2.6 Å resolution and refined to a R‐value of 18.1%. The structure was solved by molecular replacement using the coordinates from a newly published ligninase structure, LiP. CiP crystallizes in space group P212121) with two independent molecules in the asymmetric unit related by the vector 0.29b + 0.5C. The two CiP molecules are structurally identical; each contains two Ca2+ ions in positions equivalent to those found in the LiP structure. Two N‐acetylglucosamines and one mannose residue were fitted into the density adjacent to two of the three predicted glycosylation sites. The refinement also included 40 and 41 water molecules, respectively, in the two CiP molecules. The structure of CiP displays a folding very similar to that of LiP. The active sites are almost identical in the LiP and CiP structures. CiP has a much larger opening to the active site than LiP.
New forms of HMW MAP2 are preferentially expressed in the spinal cord
Authors: Couchie Dominique , Chabas Sandrine , Mavilia Carmelo , Nunez Jacques
Published: July 2002

The high molecular weight forms of microtubule‐associated protein 2 (MAP2a and b) play a central role in the specification of dendrites. RT‐PCR amplification of a portion of the N‐terminal and middle MAP2b domains of rat spinal cord cDNAs allowed identification of new variants containing both exon 8 (246 bp) and a new exon, 7A (237 bp), located at the beginning of the middle MAP2b region. The brain and the spinal cord express transcripts containing exon 8, whereas exon 7A alone or exons 7A+8 were detected, whatever the developmental stage, only in the spinal cord.
An overview of the report of the national commission on sleep disorders research
Authors: Roth T
Published: July 2002

The National Comission on Sleep Disorder Research evaluated the status of insomnia and other sleep disorders in the US. The Commission found that insomnia is prevalent affecting 20–30 million Americans, has significant morbidity especially related to attention and memory processes and cost the US an estimated $ 15 billion a year. It also estimated that all of these figures should rise significantly by the year 2000. Other sleep disorders (eg, narcolepsy and sleep apnea) although less prevalent have significant costs to patients and society associated with them. The Commission recommended that the US develop a research and education program to develop new insights into the basic mechanisms of sleep disorder. The education program needs to be directed to the general public; medical practitioners, as well as patients.
Induction of tcI 7, a gene encoding a β‐subunit of proteasome, in tobacco plants treated with elicitins, salicylic acid or hydrogen peroxide1
Authors: Etienne Philippe , Petitot Anne-Sophie , Houot Valérie , Blein Jean-Pierre , Suty Lydie
Published: July 2002

We previously isolated, by differential display and 5′ RACE (rapid amplification of cDNA ends), cDNAs corresponding to genes activated following cryptogein treatment of tobacco cell suspensions, among them tcI 7 (tcI for obacco ryptogein nduced), a gene encoding a β‐subunit of proteasome. Here, we report that tcI 7 was up‐regulated in tobacco plants treated with elicitins (cryptogein and parasiticein) that have been shown to induce a systemic acquired resistance (SAR). Moreover, subsequent inoculation of tobacco with the pathogen Phytophthora parasitica var. nicotianae (Ppn) was shown to induce an additional activation of tcI 7 in tobacco plants pretreated with cryptogein. We also showed an up‐regulation of tcI 7 by salicylic acid (SA). Moreover, accumulation of tcI 7 transcripts after treatment with cryptogein or with SA only occurred in NahG 9− tobacco plants that do not express the salicylate hydroxylase and thus are able to accumulate SA and develop a SAR. Suppressed accumulation of tcI 7 transcripts in NahG 8+ tobacco plants after cryptogein or SA treatment correlated with the loss of SAR. H2O2 was also shown to up‐regulate tcI 7 in tobacco plants. Using gene walking by PCR we cloned and sequenced the 5′ flanking region of tcI 7 containing hypothetical regulatory sequences, especially myb and NF‐κB boxes, that could be responsible for the regulation of tcI 7 by salicylic acid and H2O2 respectively.
Novel sugar‐binding specificity of the type XIII xylan‐binding domain of a family F/10 xylanase from Streptomyces olivaceoviridis E‐86
Authors: Kuno Atsushi , Kaneko Satoshi , Ohtsuki Hiroko , Ito Shigeyasu , Fujimoto Zui , Mizuno Hiroshi , Hasegawa Tsunemi , Taira Kazunari , Kusakabe Isao , Hayashi Kiyoshi
Published: July 2002

The type XIII xylan‐binding domain (XBD) of a family F/10 xylanase (FXYN) from Streptomyces olivaceoviridis E‐86 was found to be structurally similar to the ricin B chain which recognizes the non‐reducing end of galactose and specifically binds to galactose containing sugars. The crystal structure of XBD [Fujimoto, Z. et al. (2000) J. Mol. Biol. 300, 575–585] indicated that the whole structure of XBD is very similar to the ricin B chain and the amino acids which form the galactose‐binding sites are highly conserved between the XBD and the ricin B chain. However, our investigation of the binding abilities of wt FXYN and its truncated mutants towards xylan demonstrated that the XBD bound xylose‐based polysaccharides. Moreover, it was found that the sugar‐binding unit of the XBD was a trimer, which was demonstrated in a releasing assay using sugar ranging in size from xylose to xyloheptaose. These results indicated that the binding specificity of the XBD was different from those of the same family lectins such as the ricin B chain. Somewhat surprisingly, it was found that lactose could release the XBD from insoluble xylan to a level half of that observed for xylobiose, indicating that the XBD also possessed the same galactose recognition site as the ricin B chain. It appears that the sugar‐binding pocket of the XBD has evolved from the ancient ricin super family lectins to bind additional sugar targets, resulting in the differences observed in the sugar‐binding specificities between the lectin group (containing the ricin B chain) and the enzyme group.
Calcium channel β subunits differentially modulate recovery of the channel from inactivation
Authors: Jeziorski Michael C , Greenberg Robert M , Anderson Peter A.V
Published: July 2002

We examined the effects of calcium channel β subunits upon the recovery from inactivation of α1 subunits expressed in Xenopus oocytes. Recovery of the current carried by the L‐type α1 subunit (cyCav1) from the jellyfish Cyanea capillata was accelerated by coexpression of any β subunit, but the degree of potentiation differed according to which β isoform was coexpressed. The Cyanea β subunit was most effective, followed by the mammalian b3, b4, and β2a subtypes. Recovery of the human Cav2.3 subunit was also modulated by β subunits, but was slowed instead. β3 was the most potent subunit tested, followed by β4, then β2a, which had virtually no effect. These results demonstrate that different β subunit isoforms can affect recovery of the channel to varying degrees, and provide an additional mechanism by which β subunits can differentially regulate α1 subunits.
Antibody‐induced dimerization of HARPTPα–EGFR chimera suggests a ligand dependent mechanism of regulation for RPTPα
Authors: Blanchetot Christophe , den Hertog Jeroen
Published: July 2002

We developed a system to study the function of the ectodomain of RPTPα, a transmembrane protein‐tyrosine phosphatase, by fusing the HA‐epitope tagged ectodomain of RPTPα to the transmembrane and intracellular domain of the epidermal growth factor receptor, EGFR, a receptor protein‐tyrosine kinase that is activated by dimerization. Although the use of chemical crosslinkers shows that preformed HARPTPα–EGFR dimers exist, bivalent anti‐HA‐tag antibody activated HARPTPα–EGFR chimeras, suggesting this system may be used to study regulation of dimerization. We used this system to show that newborn calf serum may contain (a) potential ligand(s) for RPTPα. Our results suggest that RPTPα dimerization and thus activity may be affected by ligand binding.
NMR structure of the haem core of a novel tetrahaem cytochrome isolated from Shewanella frigidimarina: identification of the haem‐specific axial ligands and order of oxidation
Authors: Pessanha Miguel , Brennan Lorraine , Xavier António V , Cuthbertson Pauline M , Reid Graeme A , Chapman Stephen K , Turner David L , Salgueiro Carlos A
Published: July 2002

The tetrahaem cytochrome isolated during anaerobic growth of Shewanella frigidimarina NCIMB400 is a small protein (86 residues) involved in electron transfer to Fe(III), which can be used as a terminal respiratory oxidant by this bacterium. A 3D solution structure model of the reduced form of the cytochrome has been determined using NMR data in order to determine the relative orientation of the haems. The haem core architecture of S. frigidimarina tetrahaem cytochrome differs from that found in all small tetrahaem cytochromes c
3 so far isolated from strict anaerobes, but has some similarity to the N‐terminal cytochrome domain of flavocytochrome c
3 isolated from the same bacterium. NMR signals obtained for the four haems of S. frigidimarina tetrahaem cytochrome at all stages of oxidation were cross‐assigned to the solution structure using the complete network of chemical exchange connectivities. Thus, the order in which each haem in the structure becomes oxidised was determined.
Nucleotides U28–A42 and A37 in unmodified yeast tRNATrp as negative identity elements for bovine tryptophanyl‐tRNA synthetase
Authors: Carnicelli Domenica , Brigotti Maurizio , Rizzi Simona , Keith Gérard , Montanaro Lucio , Sperti Simonetta
Published: July 2002

Wild‐type bovine and yeast tRNATrp are efficiently aminoacylated by tryptophanyl‐tRNA synthetase both from beef and from yeast. Upon loss of modified bases in the synthetic transcripts, mammalian tRNATrp retains the double recognition by the two synthetases, while yeast tRNATrp loses its substrate properties for the bovine enzyme and is recognised only by the cognate synthetase. By testing chimeric bovine–yeast transcripts with tryptophanyl‐tRNA synthetase purified from beef pancreas, the nucleotides responsible for the loss of charging of the synthetic yeast transcript have been localised in the anticodon arm. A complete loss of charging akin to that observed with the yeast transcript requires substitution in the bovine backbone of G37 in the anticodon loop with yeast A37 and of C28–G42 in the anticodon stem with yeast U28–A42. Since A37 does not prevent aminoacylation of the wild‐type yeast tRNATrp by the beef enzyme, a negative combination apparently emerges in the synthetic transcript after unmasking of U28 by loss of pseudourydilation.
Masking of the Translin/Trax complex by endogenous RNA
Authors: Finkenstadt Patricia M , Jeon Mihee , Baraban Jay M
Published: July 2002

Translin and Trax are components of an RNA binding complex initially detected in extracts of brain and testes. Although other tissues appear to contain much lower or negligible levels of the Translin/Trax gel‐shift complex, we found, unexpectedly, that several of these peripheral tissues express Translin and Trax proteins at levels comparable to those present in brain. In this study, we demonstrate that the paradoxically low levels of the Translin/Trax complex in kidney and other peripheral tissues are due to masking of these sites by endogenous RNA. Thus, these findings indicate that the Translin/Trax complex is involved in RNA processing in a broader range of tissues than previously recognized.
Fidelity of metal insertion into hydrogenases
Authors: Magalon Axel , Blokesch Melanie , Zehelein Eva , Böck August
Published: July 2002

The fidelity of metal incorporation into the active center of hydrogenase 3 from Escherichia coli was studied by analyzing the inhibition of the maturation pathway by zinc and other transition metals. Hydrogenase maturation of wild‐type cells was significantly affected only by concentrations of zinc or cadmium higher than 200 μM, whereas a mutant with a lesion in the nickel uptake system displayed a total blockade of the proteolytic processing of the precursor form into the mature form of the large subunit after growth in the presence of 10 μM Zn2+. The precursor could not be processed in vitro by the maturation endopeptidase even in the presence of an excess of nickel ions. Evidence is presented that zinc does not interfere with the incorporation of iron into the metal center. Precursor of the large subunit accumulated in nickel proficient cells formed a transient substrate complex with the cognate endoprotease HycI whereas that of zinc‐supplemented cells did not. The results show that zinc can intrude the nickel‐dependent maturation pathway only when nickel uptake is blocked. Under this condition zinc appears to be incorporated at the nickel site of the large subunit and delivers a precursor not amenable to proteolytic processing since the interaction with the endoprotease is blocked.
Sites of interaction of thioredoxin with sorghum NADP‐malate dehydrogenase
Authors: Goyer Aymeric , Decottignies Paulette , Issakidis-Bourguet Emmanuelle , Miginiac-Maslow Myroslawa
Published: July 2002

The activation pathway of the chloroplastic NADP‐dependent malate dehydrogenase (MDH) by reduced thioredoxin has been examined using a method based on the mechanism of thiol/disulfide interchanges, i.e. the transient formation of a mixed disulfide between the target and the reductant. This disulfide can be stabilized when each of the partners is mutated in the less reactive cysteine of the disulfide/dithiol pair. As NADP‐MDH has two regulatory disulfides per monomer, four different single cysteine mutants were examined, two for the C‐terminal bridge and two for the N‐terminal bridge. The results clearly show that the nucleophilic attack of thioredoxin on the C‐terminal bridge proceeds through the formation of a disulfide with the most external Cys377. The results are less clear‐cut for the N‐terminal cysteines and suggest that the Cys24–Cys207 disulfide bridge previously proposed to be an intermediary step in MDH activation can form only when the C‐terminal disulfide is reduced.
Thr40 and Met122 are new partial loss‐of‐function natural mutations of the human melanocortin 1 receptor
Authors: Jiménez-Cervantes Celia , Germer Silke , González Petra , Sánchez Jesús , Sánchez Concepción Olivares , Garcı́a-Borrón José Carlos
Published: July 2002

Activation by melanocortins of the melanocortin 1 receptor (MC1R), expressed in epidermal melanocytes, stimulates melanogenesis. Human MC1R gene loss‐of‐function mutations are associated with fair skin, poor tanning and increased skin cancer risk. We identified two natural alleles: Ile40Thr, probably associated with skin types I–II, and Val122Met. Val122Met bound [125I][Nle4, D‐Phe7]‐α‐melanocyte stimulating hormone with lower affinity than the wild‐type. Dose–response curves of cAMP accumulation were right‐shifted for both forms. The Val122Met form failed to achieve maximal cAMP responses comparable to the wild‐type or Ile40Thr receptors. Thus, the Ile40Thr and Val122Met variants are partial loss‐of‐function natural mutations of MC1R.
Electron spin echo envelope modulation studies of the semiquinone anion radical of cholesterol oxidase from Brevibacterium sterolicum
Authors: Medina Milagros , Vrielink Alice , Cammack Richard
Published: July 2002

The electron spin echo envelope modulation (ESEEM) technique of pulsed EPR spectroscopy was applied to the anionic semiquinone of the cholesterol oxidase flavin cofactor, formed when the enzyme was photoreduced in the presence of 5‐deazariboflavin and EDTA. Fourier transforms of the three‐pulse ESEEM spectra showed the presence of 14N nuclei magnetically coupled to the paramagnet. In 2H2O buffer the surroundings of the flavin ring were shown to be accessible to solvent exchange, with a deuterium population in close proximity to the paramagnetic centre. Upon binding of the pseudosubstrate, dehydroisoandrosterone, subtle changes were observed in the coupling to nitrogen nuclei, which are interpreted as changes in the electron density distribution of the flavin ring system. The results are discussed in terms of the three‐dimensional structure reported for the protein and the flavin ring architecture.
Oxidation of NG‐hydroxyl‐l‐arginine to nitric oxide mediated by respiratory burst: an alternative pathway to NO synthesis
Authors: Modolell Manuel , Eichmann Klaus , Soler Germán
Published: July 2002

N
G‐Hydroxy‐l‐arginine is an intermediate metabolite in the synthesis of nitric oxide that is upregulated and secreted during acute inflammation in vivo. Previous reports have shown that chemically induced superoxide anion oxidizes N
G‐hydroxy‐l‐arginine to nitric oxide. Here, we demonstrate that this reaction takes place physiologically in phagocytic cells during the respiratory burst, and is independent of the presence of nitric oxide synthase.
Ras GTPase‐activating protein‐associated p62 is a major v‐Src‐SH3‐binding protein
Authors: Williger Ben-Tsion , Liscovitch Mordechai
Published: July 2002

© 1997 Federation of European Biochemical Societies.
Functional mapping reveals the importance of yeast cytochrome b C‐terminal region in assembly and function of the bc1 complex
Authors: Edderkaoui Bouchra , Meunier Brigitte , Colson-Corbisier Anne-Marie
Published: July 2002

© 1997 Federation of European Biochemical Societies.
Characterization of the 5′‐flanking regions of plasminogen‐related genes A and B
Authors: Kida Masafumi , Wakabayashi Sadao , Ichinose Akitada
Published: July 2002

© 1997 Federation of European Biochemical Societies.
Mastoparan and Rab3AL peptide potentiation of calcium‐independent secretory activity in rat melanotrophs is inhibited by GDPβS
Authors: Rupnik M , Law G.J , Mason W.T , Zorec R
Published: July 2002

The whole‐cell patch‐clamp membrane capacitance measurement was used to monitor secretory activity in rat melanotrophs, while rab3AL, putative effector domain peptides of Rab3 small GTPases (20–30 kDa), were introduced into cytosol. In melanotrophs dialyzed with calcium free solutions membrane capacitance tends to decrease slightly. This decrease is further potentiated with GDPβS (500 μM). We found that rab3AL (100 μM) stimulated secretory activity in the absence of calcium. The rab3AL response was qualitatively comparable to the response to mastoparan (1 μM), an activator of certain heterotrimeric GTP‐binding proteins. Interestingly, inclusion of GDPβS (500 μM) resulted in a blockade of both rab3AL and mastoparan induced responses. We conclude that rab3AL and mastoparan induce calcium‐independent stimulation of secretory activity in rat melanotrophs by activation of a downstream heterotrimeric GTP‐binding protein.
Probing the structure of HIV‐1 Rev by protein footprinting of multiple monoclonal antibody‐binding sites
Authors: Jensen Torben Heick , Jensen Allan , Szilvay Anne Marie , Kjems Jørgen
Published: July 2002

Human immunodeficiency virus type 1 (HIV‐1) Rev is a small RNA‐binding protein which is essential for viral replication. To investigate the structure of Rev we have mapped the binding sites of a panel of monoclonal antibodies (mAb) by protein footprinting and identified a mAb protecting amino acids within both the N‐ and C‐terminal parts of Rev. Our mapping results support a previously proposed structure (Auer et al., Biochemistry, 33 (1994) 2988–2996) predicting that a helix–loop–helix motif in Rev brings the termini of the protein into proximity. Furthermore, we demonstrate that the binding sites mapped by protein footprinting are in agreement with conventional epitope mapping results and that this technique provides an advantageous strategy for mapping discontinuous sites.
Characterisation and preliminary X‐ray diffraction analysis of human pancreatic procarboxypeptidase A2
Authors: Reverter David , Garcı́a-Sáez Isabel , Catasús Lluis , Vendrell Josep , Coll Miquel , Avilés Francesc X
Published: July 2002

Human procarboxypeptidase A2 has been expressed in a Pichia pastoris heterologous system and purified by hydrophobic interaction and anion exchange chromatographies. The hydrolytic action of carboxypeptidase A2 on peptide substrates with different lengths and residues at the C‐terminus was analysed, and a preference towards long substrates with aromatic amino acids in their C‐terminal end, particularly tryptophan, was found; with such substrates its activity is similar or higher than that of bovine carboxypeptidase A1. Procarboxypeptidase A2 has been crystallised using a vapour diffusion approach; the crystals obtained belong to the monoclinic system, spacegroup P21, and present one procarboxypeptidase A2 molecule per asymmetric unit. The crystals diffract beyond 1.8 Å resolution and are suitable for detailed X‐ray analysis.
Identification of an ABC transporter gene that exhibits mRNA level overexpression in fluoroquinolone‐resistant Mycobacterium smegmatis
Authors: Banerjee Sanjiban K , Misra Parimal , Bhatt Kamlesh , Mande Shekhar C , Chakraborti Pradip K
Published: July 2002

We describe here the PCR amplification of a DNA fragment (mtp1) from Mycobacterium smegmatis using primers derived from consensus sequences of the ABC family of transporters. The fragment encodes amino acid sequences that exhibited significant homology with different ABC transporters. Amino acid sequence alignment of the full length gene with other transporters identified the ABC protein as the B‐subunit of the phosphate specific transporter. Strikingly, a M. smegmatis colony which exhibited a high level of ciprofloxacin resistance showed mRNA level overexpression of mtp1. Thus this is the first report in any prokaryote indicating differential expression of an ABC transporter in a fluoroquinolone resistant colony.
Coexpression of GTP cyclohydrolase I and inducible nitric oxide synthase mRNAs in mouse osteoblastic cells activated by proinflammatory cytokines
Authors: Togari Akifumi , Arai Michitsugu , Mogi Makio , Kondo Ayami , Nagatsu Toshiharu
Published: July 2002

Proinflammatory cytokines, a combination of IL‐1β, TNF‐α, and IFN‐γ, caused mRNA expression of GTP cyclohydrolase I (GTP‐CH), the rate‐limiting enzyme in tetrahydrobiopterin (BH4) biosynthesis, and of inducible nitric oxide synthase (iNOS) in a well‐characterized osteoblastic clone MC3T3‐E1 cell line. We found the expression of the GTP‐CH gene in osteoblasts for the first time. The expression of GTP‐CH and iNOS mRNAs was found to be maximal at 3 and 9 h, respectively. The expression of both genes elicited increases in BH4 and NO levels. Pharmacological studies using 2,4‐diamino‐6‐hydroxypyrimidine, an inhibitor of GTP‐CH activity, showed that BH4 is involved in the activity of iNOS, but not in the induction of iNOS mRNA. The results using an inhibitor of nuclear factor (NF)‐κB and activating protein‐1 (AP‐1) activation suggested that coinduction of the two genes in response to cytokines occurred via activation of NF‐κB and AP‐1. In MC3T3‐E1 cells BH4 and sepiapterin, producing BH4, could protect against apoptosis, i.e. the degradation of nuclear DNA in the cells, induced by NO derived from S‐nitroso‐N‐acetyl‐d,l‐penicillamine. These results suggest that the induction of BH4 together with NO by proinflammatory cytokines could protect against NO‐induced apoptosis in MC3T3‐E1 cells.
Potent inhibition of specific diadenosine polyphosphate hydrolases by suramin
Authors: Rotllán P , Rodrı́guez-Ferrer C.R , Asensio A.C , Oaknin S
Published: July 2002

The cytosolic enzymes asymmetrical diadenosine tetraphosphate hydrolase (EC 3.6.1.17, Ap4Aase) and diadenosine triphosphate hydrolase (EC 3.6.1.29, Ap3Aase) are inhibited competitively by suramin. Ap4Aase and Ap3Aase were assayed in cytosolic rat brain extracts using fluorogenic analogues of the respective substrates diadenosine tetraphosphate (Ap4A) and diadenosine triphosphate (Ap3A). K
i values for suramin as inhibitor of Ap4Aase and Ap3Aase were 5×10−6 M and 3×10−7 M, respectively. Results indicate that suramin or suramin‐like derivatives may be useful tools to investigate diadenosine polyphosphate cleaving enzymes and that the intracellular diadenosine polyphosphate metabolism may be a pharmacological target of suramin with biological and clinical implications.
Agonist stimulation of B1 and B2 kinin receptors causes activation of the MAP kinase signaling pathway, resulting in the translocation of AP‐1 in HEK 293 cells
Authors: Naraba Hiroaki , Ueno Akinori , Kosugi Yae , Yoshimura Mineka , Murakami Makoto , Kudo Ichiro , Oh-ishi Sachiko
Published: July 2002

In response to bradykinin, phosphorylated MAP kinases (ERK‐1 and ERK‐2) were abundantly increased in HEK 293 cells, which overexpress the rat B2 kinin receptor. In a similar way des‐Arg9‐bradykinin stimulation of B1 kinin receptor‐overexpressing HEK 293 cells caused activation of the same species of MAP kinase. Furthermore, nuclear translocation of transcription factor AP‐1 was also found in the cells after stimulation with either agonist. PD98059, a MAP kinase kinase (MEK‐1) inhibitor, blocked the agonist‐induced AP‐1 translocation as well as the phosphorylation of the MAP kinases. This communication provides the first evidence for both B1 and B2 kinin receptors mediating the MAP kinase signaling pathway to activate AP‐1.
Altered processing of procholecystokinin in carboxypeptidase E‐deficient fat mice: differential synthesis in neurons and endocrine cells
Authors: Lacourse Karen A , Friis-Hansen Lennart , Samuelson Linda C , Rehfeld Jens F
Published: July 2002

The fat mouse strain exhibits a late‐onset obesity syndrome associated with a mutation in the gene encoding carboxypeptidase E (CPE). CPE plays a central role in the biosynthesis of many regulatory peptides. Therefore, we examined the processing of procholecystokinin (proCCK) in the brain (neurons) and small intestine (endocrine cells) of fat/fat mice. In the brain, bioactive CCK was markedly reduced (7.9±1.0 pmol/g in fat/fat mice vs. 82.5±11.2 pmol/g in controls), but the concentration of the CPE substrate, glycyl‐arginine‐extended CCK, was elevated 105‐fold. In contrast, the concentration of bioactive CCK in intestinal endocrine cells was unaffected. Endocrine cell processing was, nevertheless, altered with a 33‐fold increase in glycyl‐arginine‐extended CCK. Interestingly, although total proCCK products were normal in the brain they were elevated 3‐fold in the intestine, indicating that biosynthesis is upregulated in endocrine cells but not neurons to compensate for the processing defect. These results demonstrate that the CPE mutation differentially affects CCK processing in these two cell types. Intestinal CCK synthesis more closely resembles progastrin processing, suggesting the presence of an endocrine‐specific biosynthetic regulatory mechanism not present in neurons.
The catalytic mechanism of amidase also involves nitrile hydrolysis
Authors: Kobayashi Michihiko , Goda Masahiko , Shimizu Sakayu
Published: July 2002

The amidase from Rhodococcus rhodochrous J1, which hydrolyzes an amide to an acid and ammonium, was surprisingly found to catalyze the hydrolytic cleavage of the C‐N triple bond in a nitrile to form an acid and ammonium stoichiometrically. The amidase exhibited a K
m of 3.26 mM for benzonitrile in contrast to that of 0.15 mM for benzamide as the original substrate, but the V
max for benzonitrile was about 1/6000 of that for benzamide. A mutant amidase containing alanine instead of Ser195, which is essential for amidase catalytic activity, showed no nitrilase activity, demonstrating that this residue plays a crucial role in the hydrolysis of nitriles as well as amides.
Beta‐human chorionic gonadotropin and prolactin assays in cervicovaginal secretions as a predictor of preterm delivery
Authors: Guvenal T , Kantas E , Erselcan T , Culhaoglu Y , Cetin A
Published: July 2002

Objective: To evaluate and to compare the predictive value of cervicovaginal beta‐hCG and prolactin levels in spontaneous preterm delivery. Methods: The preterm labor group and normal pregnancy group consisted of 17 and 43 patients between 24 and 36 weeks’ gestation, respectively. A single cervicovaginal beta‐hCG and prolactin measurement were made in both groups. Results: Cervicovaginal beta‐hCG and prolactin levels were significantly higher in the preterm group when compared with those of the term delivery group (P=0.031, P=0.026, respectively). The optimal cut‐off value for beta‐hCG (27.1 mIU/ml) gave a sensitivity level of 87.5% (47.4–97.9; 95% C.I.) at a specificity of 65.4% (50.9–78.0; 95% C.I.) with positive and negative predictive values of 28% and 97%, respectively. The optimal cut‐off value for prolactin (1.8 ng/ml) gave a sensitivity level of 50% (16.0–84.0; 95% C.I.) at a specificity of 96% (86.8–99.4; 95% C.I.) with positive and negative predictive values of 67% and 93%, respectively. Conclusions: Cervicovaginal beta‐hCG measurement in patients with preterm labor may be used as a predictive test. Cervicovaginal prolactin is not a sensitive test compared with the beta‐hCG test.
Ultrasound guided embryo transfer significantly improves pregnancy rates in women undergoing oocyte donation
Authors: Lindheim S.R , Cohen M.A , Sauer M.V
Published: July 2002

Objectives: Recent reports suggest ultrasound (US) guided embryo transfer (ET) improves pregnancy rates. Using the ovum donation model to eliminate confounding variables, we assessed the impact of US guided ET on pregnancy rates, implantation rates, and multiple gestation rates. Methods: All women who underwent IVF‐ET cycles using donated oocytes from November 1997 to September 1998 (n=137) were evaluated retrospectively. ET from November 1997 to April 1998 were performed without US, while all ET from May 1998 to September 1998 were performed using transvaginal or transabdominal US. ET was further categorized as easy or difficult. Difficult ET was defined as requiring at least two attempts and/or the presence of blood on the catheter and/or >5 min. Results: Pregnant patients (n=73) were similar with respect to the number and morphology of the embryos transferred compared to non‐pregnant patients (n=65). US guidance significantly improved implantation and pregnancy rates in cycles with easy transfers [28.8 vs. 18.4% and 63.1 vs. 36.1%, respectively (P<0.05)] without impacting multiple pregnancy rates. Conclusion: US guided ET is simple and reassuring and appears to significantly improve pregnancy outcomes in ovum donation cycles by optimizing the placement of embryos.
Developmental expression of the NGF receptor p140trk in the septohippocampal system of the rat:a quantitative analysis
Authors: Cirulli Francesca , Shooter Eric M. , Levine Seymour
Published: July 2002

An RNAse protection assay was used to identify p140trk mRNA in the developing rat septohippocampal system. In both the septum and hippocampus, levels of p140trk mRNA were low at birth and increased thereafter. Levels of transcripts were found to be much higher in the septum than in the hippocampus, whereas another brain region, the hypothalamus, showed levels of expression intermediate between these two structures. Only one isoform of the p140trk receptor was found to be expressed in the rat central nervous system (CNS) during development. This isoform corresponds to the one preferentially expressed in neural tissues in the adult animal. These data show that expression of the high affinity nerve growth factor (NGF) receptor is developmentally regulated during postnatal brain development and suggest that it might mediate NGF effects on developing central cholinergic systems.
Biosynthesis of progesterone derived neurosteroids by developing avian CNS : in vitro effects on the gabaa receptor complex
Authors: Pignataro Leonardo , Lerner Alejandro A.Colman , Barañao J.Lino , De Plazas Sara Fiszer
Published: July 2002

It has been demonstrated in different vertebrate species that the GABAA receptor complex is modulated by certain steroids. Theses results prompted work on the synthesis of these neurosteroids in the Central Nervous System. However, there are scarcely any studies analyzing their production or their modulatory effects on this receptor during development. In this work, the biosynthesis of [14C]progesterone metabolites as well as the characterization of their in vitro effects on the GABAA receptor complex in developing chick optic lobe were investigated. Studies on progesterone metabolism indicated that this steroid was converted to 5β‐pregnanedione, 5β‐pregan‐3β‐ol‐20‐one, and a 20‐hydroxy derivative. Radioactive progesterone was completely metabolized at early embryonic stages, and a great proportion of 5β‐pregnanedione was converted to 5β‐pregnan‐3β‐ol‐20‐one. Thus, it seems that some of the steroidogenic activities present in chick optic lobe are age‐dependent, though greater at embryonic stages. Results from in vitro modulation of [3H]flunitrazepam binding by 5β‐pregnan‐3β‐ol‐20‐one indicated that this steroid produces a one‐component‐concentration dependent enhancement above control binding. 5β‐pregnan‐3β‐ol‐20‐one EC50 values were 0.195±0.049, 0.101±0.017, 0.147±0.009, and 0.569±0.114 μM, and Emax were 22.37±1.57, 23.67±4.02, 29.01±1.08, and 15.11±2.67% at embryonic days 11, 14, hatching, and postnatal day 21, respectively.

In conclusion, the biosynthesis of 5β‐pregnan‐3β‐ol‐20‐one from progesterone in developing chick optic lobe, together with its ability to modulate the GABAA receptor present in such tissues, suggests a physiological role of this neurosteroid in developing avian Central Nervous System.
Effects of neonatal cholinergic basal forebrainlesions on excitatory amino acid receptors in neocortex
Authors: Hohmann Christine F. , Wallace Sarah A. , Johnston Michael V. , Blue Mary E.
Published: July 2002

The role of cholinergic basal forebrain projections in the modulation of corticalplasticity and associated functional changes is currently the subject of renewed attention.Excitatory amino acid receptors have been identified as mediators of cortical topographic efferentand afferent information. In addition some of these receptors, notably the NMDA andmetabotropic [mGluR] type, participate in cortical plasticity. Growing evidence suggests thatinteractions between cholinergic and glutamatergic systems contribute to cognitive corticalfunctions and their anatomical and physiological substrates. Though cholinergic and glutamatergicmechanisms have both been shown to be involved in cortical morphogenesis, few studies haveattempted to study their interactions in development. The present study investigates the effect ofneonatal lesions to the cholinergic basal forebrain on NMDA, AMPA and mGluR receptors inBALB/CByJ mice, at two different developmental ages. We demonstrated previously that nBMlesions at birth result in transient cholinergic depletion for the first two postnatal weeks,substantial morphogenetic alterations in neocortex and cognitive deficits by adulthood. We showhere that unilateral neonatal lesions result in decreases in NMDA and AMPA receptors butincreases in mGluRs during the second postnatal week (PND 14). At 30 days postnatal, lesionmediated changes were attenuated, compared with PND 14, but significant sex differences incontrol and nBM lesioned mice were apparent. These data support the notion thatcholinergic/glutamatergic interactions are important during early cortical morphogenesis.Moreover, our results highlight the fact that cholinergic as well glutamatergic developmentalmechanisms are sexually dimorphic.
Association between severity of schizophrenic symptoms and urinary retention
Authors: Shiloh R. , Weizman A. , Dorfman-Etrog P. , Weizer N. , Munitz H.
Published: July 2002

A case is presented in which severe urinary retention (UR) occurred during an acute psychotic exacerbation of paranoid schizophrenia. The voiding dysfunction was apparent during continuous treatment with unchanged doses of haloperidol, and it completely resolved with the remission of the psychotic symptoms. A clear temporal correlation was evident between the patient’s mental status, the Brief Psychiatric Rating Scale (BPRS) score and the degree of the UR as assessed by quantitatively measuring the total daily postvoiding urine residues. We could not relate the UR to any apparent general medical condition or to the haloperidol treatment. The presented data suggests that UR in schizophrenic patients might be the end-result of various psychosis-related mechanisms.
Variables associated with the hospitalization of psychiatric emergencies evaluated in the community
Authors: Turrina C. , Lucchi F. , Este R. , Micciolo R. , Fazzari G. , Sacchetti E.
Published: July 2002

We investigated hospitalization factors in acutely ill patients visited by psychiatrists at home. A series of 100 consecutive calls for psychiatric emergencies of a community mental health centre were investigated with a structured evaluation of psychiatric symptoms and aggressiveness (IEF, GAS, and VSAS). First order interactions were tested, and selected variables were tested with logistic regression analysis. Admission was significantly associated with GAS scores (low scores were found in 92.6% of admitted patients vs. 43.8% of patients not admitted), paranoid delusions (66.7 vs. 39.7%), and lack of social support (70.4 vs. 30.1%). Multivariate analysis confirmed a significant independent effect only for low GAS score and lack of social support. The study replicated some findings from research on hospitalization in emergency wards, while other factors, such as ’diagnosis’ and ’suicide risk’, were not significant.
Catatony in Graves' disease
Authors: Rudolf J , Grond M , Neveling M , Heiss W-D
Published: July 2002

We report a 27-year-old female patient with prior history of Graves' disease and relapsing episodes of tachycardia, hyperpyrexia, muscular rigidity and coma. With the subsequent manifestation of an acute schizophreniform psychotic disorder unresponsive to neuroleptics, the primary syndrome was re-classified as febrile catatony. Hyperthyroidism was ruled out with normal serum thyroid hormone levels, as were toxic effects of thyrostatic treatment, drug-induced hypothyroidism and a malignant neuroleptic syndrome. All psychiatric symptoms subsided completely following subtotal thyroidectomy. Febrile catatatony has to be added to the spectrum of psychotic phenomena that may be caused by Graves' disease, irrespective of serum thyroid hormone levels.
Relations between medical history, clinical findings and plasma N‐terminal proatrial natriuretic peptide in patients in primary health care
Authors: Smith Jørgen A. , Bruusgaard Dag , Bodd Egil , Hall Christian
Published: July 2002

Background:

recent studies indicate that measurement of natriuretic peptides may be a valuable tool to improve the quality of the diagnosis of heart failure in general practice.

Aim:

the aim of the present study was to examine the relationship between the plasma level of the natriuretic peptide N‐terminal proANP and symptoms and signs of heart failure in patients from general practice in the Oslo area.

Methods and Results:

we undertook a survey of 499 patients consecutively enrolled from the practice of 27 practitioners. One hundred and twenty‐nine patients were classified as having possible or some degree of heart failure. The plasma concentration of N‐terminal proANP increased with severity of heart failure as judged from clinical examination. In multivariate analysis age, history of heart disease, plasma creatinine, use of beta‐blockers and digitalis, oedemas and atrial fibrillation were the main determinants of plasma N‐terminal proANP.

Conclusion:

while there was an overall increase in N‐terminal proANP values with increasing symptoms and degree of heart failure, no single finding was closely related to N‐terminal proANP. Treatment effects and diagnostic errors may both influence the relationship between N‐terminal proANP and clinical findings. The current study has demonstrated the feasibility of using N‐terminal proANP by general practitioners for the potentially improved diagnosis of heart failure. Further research is required to determine the precise role of this assay in clinical practice.
Prognosis of acute myocardial infarction in the thrombolytic era: medical evaluation is still valuable
Authors: Nicolau José C. , Serrano Carlos V. , Garzon Sérgio A.C. , Ramires José A.F.
Published: July 2002

Background:

Modern and sophisticated technology for the management of myocardial infarction has progressively devalued medical evaluation.

Hypothesis:

This study was undertaken to assess the importance of the findings of medical evaluation at hospital presentation, in patients with acute myocardial infarction.

Methods:

Data from 590 thrombolytic‐treated myocardial infarction patients were analyzed. The patients were grouped according to their clinical status on arrival at hospital. A modified Forrester classification — subset II was divided according to the absence (IIa) or presence (IIb) of symptoms — was applied. Short‐ (14 days) and long‐term (up to 10 years) survival was analyzed and 19 independent variables were included in the multivariate models.

Results:

Short‐term survival was 95.6% for subset I, 83.3% for subset IIa, 60% for subset IIb, 54.6% for subset III, and 34.8% for subset IV (P < 0.001). By multiple regression analysis, lower clinical subsets (P < 0.001), fewer coronary arteries with disease (P ‐ 0.006), younger age (P ‐ 0.014), absence of reinfarction (P ‐ 0.034), longer interval between streptokinase infusion and coronary arteriography (P ‐ 0.016), and higher left ventricular ejection fraction (P ‐ 0.037) demonstrated significant and independent correlation with short‐term survival. Long‐term survival for the total population was 71 ± 3.6% for subset I, 54.4 ± 8.5% for subset IIa, 20.8 ± 9.4% for subset IIb, 54.5 ± 15% for subset III, and 0% for subset IV (P < 0.001). Using Cox regression analysis, lower clinical subsets (P < 0.001), younger age (P < 0.001), higher global left ventricular ejection fraction (P < 0.001), and fewer coronary arteries with disease (P ‐ 0.021) correlated independently and significantly with long‐term survival. When excluding data from patients who died before the short‐term follow‐up (n ‐ 532), lower clinical subsets remained an important predictor of long‐term survival (P < 0.001).

Conclusion:

Clinical classification at hospital presentation is a powerful predictor of short‐ and long‐term survival post‐myocardial infarction.
Cardioselective peripheral noradrenergic deficiency in Lewy body synucleinopathies
Authors: Lamotte Guillaume , Holmes Courtney , Sullivan Patricia , Lenka Abhishek , Goldstein David S.
Published: November 2020

Objective

Lewy body (LB) synucleinopathies such as Parkinson’s disease (PD) entail profound cardiac norepinephrine deficiency. The status of sympathetic noradrenergic innervation at other extracranial sites has been unclear. Although in vivo neuroimaging studies have indicated a cardioselective noradrenergic lesion, no previous study has surveyed peripheral organs for norepinephrine contents in LB diseases. We reviewed 18F‐dopamine (18F‐DA) positron emission tomographic images and postmortem neurochemical data across several body organs of controls and patients with the LB synucleinopathies PD and pure autonomic failure (PAF) and the non‐LB synucleinopathy multiple system atrophy (MSA).

Methods

18F‐DA–derived radioactivity in the heart, liver, spleen, pancreas, stomach, kidneys, thyroid, and submandibular glands were analyzed from 145 patients with LB synucleinopathies (112 PD, 33 PAF), 74 controls, and 85 MSA patients. In largely separate cohorts, postmortem tissue norepinephrine data were reviewed for heart, liver, spleen, pancreas, kidney, thyroid, submandibular gland, and sympathetic ganglion tissue from 38 PD, 2 PAF, and 5 MSA patients and 35 controls.

Results

Interventricular septal 18F‐DA–derived radioactivity was decreased in the LB synucleinopathy group compared to the control and MSA groups (P < 0.0001 each). The LB and non‐LB groups did not differ in liver, spleen, pancreas, stomach, or kidney 18F‐DA–derived radioactivity. The LB synucleinopathy group had markedly decreased apical myocardial norepinephrine, but normal tissue norepinephrine in other organs. The MSA group had normal tissue norepinephrine in all examined organs.

Interpretation

By in vivo sympathetic neuroimaging and postmortem neurochemistry peripheral noradrenergic deficiency in LB synucleinopathies is cardioselective. MSA does not involve peripheral noradrenergic deficiency.
Thermophysical Properties of an Fe57.75Ni19.25Mo10C5B8 Glass‐Forming Alloy Measured in Microgravity
Authors: Mohr Markus , Hofmann Douglas C. , Fecht Hans-Jörg
Published: November 2020

Iron‐based metallic glasses are among the lowest‐cost form of amorphous metals and have numerous potential applications, such as wear‐resistant coatings, cutting tools, and gears. There is an increased interest for using this novel alloys as protective coatings and to produce structural elements by additive manufacturing. If an accelerated process development is desired, computer‐based process simulations are nowadays a vital tool. As a consequence, high‐quality measurements of the thermophysical properties in the solid and liquid phases are essential for developing numerical simulation models and suitable processing parameters. Due to the high melt reactivity of liquid metals at high temperatures, measurements using conventional containers are challenging, hence containerless methods have to be used. Herein, the thermophysical properties of an Fe‐based metallic glass‐former have been measured in the liquid phase using the electromagnetic levitator ISS‐EML on‐board the International Space Station (ISS).