bluuebunny/crossref_metadata_2025 huggingface dataset:
Pathophysiological relevance of mitochondria in NAD+ metabolism
Authors: Di Lisa Fabio , Ziegler Mathias
Published: July 2002

Pyridine nucleotides are mostly stored within mitochondria where they are involved in different functions ranging from energy metabolism to cellular signaling. Here we discuss the mechanisms of mitochondrial NAD+ metabolism and release that may contribute to the crucial roles played by these organelles as triggers or amplifiers of physiological and pathological events.
Genes modulated by histone acetylation as new effectors of butyrate activity
Authors: Della Ragione Fulvio , Criniti Vittoria , Della Pietra Valentina , Borriello Adriana , Oliva Adriana , Indaco Stefania , Yamamoto Tadashi , Zappia Vincenzo
Published: July 2002

A wealth of evidence correlates the chemopreventive activity of a fiber‐rich diet with the production of butyrate. In order to identify the genes transcriptionally modulated by the molecule, we analyzed the expression profile of butyrate‐treated colon cancer cells by means of cDNA expression arrays. Moreover, the effect of trichostatin A, a specific histone deacetylase inhibitor, was studied. A superimposable group of 23 genes out of 588 investigated is modulated by both butyrate and trichostatin A. Among them, a major target was tob‐1, a gene involved in the control of cell cycle. tob‐1 is also up‐regulated by butyrate in a neuroblastoma‐derived cell line, and its overexpression in the colon cells caused growth arrest. Our findings represent an extensive analysis of genes modulated by butyrate and identify completely new effectors of its biological activities.
Identification of an expanded set of translationally active methionine analogues in Escherichia coli
Authors: Kiick K.L. , Weberskirch R. , Tirrell D.A.
Published: July 2002

Amino acid incorporation into proteins in vivo is controlled most stringently by the aminoacyl‐tRNA synthetases. Here we report the incorporation of several new methionine analogues into protein by increasing the rate of their activation by the methionyl‐tRNA synthetase (MetRS) of Escherichia coli. cis‐Crotylglycine (4), 2‐aminoheptanoic acid (7), norvaline (8), 2‐butynylglycine (11), and allylglycine (12) will each support protein synthesis in methionine‐depleted cultures of E. coli when MetRS is overexpressed and the medium is supplemented with the analogue at millimolar concentrations. These investigations suggest important opportunities for protein engineering, as expansion of the translational apparatus toward other amino acid analogues by similar strategies should also be possible.
Uncoupling protein‐3: a new member of the mitochondrial carrier family with tissue‐specific expression
Authors: Boss Olivier , Samec Sonia , Paoloni-Giacobino Ariane , Rossier Colette , Dulloo Abdul , Seydoux Josiane , Muzzin Patrick , Giacobino Jean-Paul
Published: July 2002

Brown adipose tissue (BAT) and skeletal muscle are important sites of nonshivering thermogenesis. The uncoupling protein‐1 (UCP1) is the main effector of nonshivering thermogenesis in BAT and the recently described ubiquitous UCP2 [1]has been implicated in energy balance. In an attempt to better understand the biochemical events underlying nonshivering thermogenesis in muscle, we screened a human skeletal muscle cDNA library and isolated three clones: UCP2, UCP3L and UCP3S. The novel UCP3 was 57% and 73% identical to human UCP1 and UCP2, respectively, highly skeletal muscle‐specific and its expression was unaffected by cold acclimation. This new member of the UCP family is a candidate protein for the modulation of the respiratory control in skeletal muscle.
Affinity for α‐tocopherol transfer protein as a determinant of the biological activities of vitamin E analogs
Authors: Hosomi Akihiro , Arita Makoto , Sato Yuji , Kiyose Chikako , Ueda Tadahiko , Igarashi Osamu , Arai Hiroyuki , Inoue Keizo
Published: July 2002

α‐Tocopherol transfer protein (αTTP), a product of the gene which causes familial isolated vitamin E deficiency, plays an important role in determining the plasma vitamin E level. We examined the structural characteristics of vitamin E analogs required for recognition by αTTP. Ligand specificity was assessed by evaluating the competition of non‐labeled vitamin E analogs and α‐[3H]tocopherol for transfer between membranes in vitro. Relative affinities (RRR‐α‐tocopherol=100%) calculated from the degree of competition were as follows: β‐tocopherol, 38%; γ‐tocopherol, 9%; δ‐tocopherol, 2%; α‐tocopherol acetate, 2%; α‐tocopherol quinone, 2%; SRR‐α‐tocopherol, 11%; α‐tocotrienol, 12%; trolox, 9%. Interestingly, there was a linear relationship between the relative affinity and the known biological activity obtained from the rat resorption‐gestation assay. From these observations, we conclude that the affinity of vitamin E analogs for αTTP is one of the critical determinants of their biological activity.
Direct action of nitric oxide on osteoblastic differentiation
Authors: Hikiji Hisako , Shin Wee Soo , Oida Shinichiro , Takato Tuyoshi , Koizumi Toshiyuki , Toyo-oka Teruhiko
Published: July 2002

The effect of nitric oxide (NO) on osteoblastic differentiation was examined in cultured mouse osteoblasts. Interleukin‐1β and tumor necrosis factor‐α expressed inducible NO synthase gene with little effect on constitutive NO synthase gene. These cytokines increased NO production, which was inhibited by l‐NMMA pretreatment, and decreased alkaline phosphatase (AIPase) activity, which was not restored by l‐NMMA. Furthermore, NO donors, sodium nitroprusside and NONOate dose‐dependently elevated AIPase activity and expression of osteocalcin gene. These results suggest that NO directly facilitates osteoblastic differentiation and the cytokine‐induced inhibition of AIPase activity is mediated via mechanism other than NO.
ADP‐ribosylation of tuftsin suppresses its receptor‐binding capacity and phagocytosis‐stimulating activity to murine peritoneal macrophages
Authors: Terashima Masaharu , Hara Nobumasa , Badruzzaman Muhammad , Shimoyama Makoto , Tsuchiya Mikako
Published: July 2002

Arginine‐specific ADP‐ribosyltransferase present in granules of chicken polymorphonuclear leukocytes (so‐called heterophils) is released into the extracellular space by stimulus of calcium ionophore A23187 or opsonized zymosan [Terashima et al. (1996) J. Biochem. 120, 1209–1215]. In the present work, we examined extracellular targets of the released transferase and identified tuftsin, a phagocytosis‐stimulating tetrapeptide derived from leukokinin, as a preferential substrate of the enzyme in chicken plasma. Specific binding of FITC‐tuftsin to murine peritoneal macrophages, observed under a fluorescent microscope, was impaired by ADP‐ribosylation of the labelled peptide. Phagocytic assay analyzed by flow cytometry revealed that ADP‐ribosylation of tuftsin decreased its phagocytosis‐stimulating activity towards the macrophages. Thus, the ADP‐ribosylation of tuftsin apparently decreases its biological activity and ADP‐ribosylation may possibly be involved in inflammatory processes through alterations in tuftsin activity.
Gliotoxicity, reverse transcriptase activity and retroviral RNA in monocyte/macrophage culture supernatants from patients with multiple sclerosis
Authors: Ménard Armelle , Amouri Rim , Michel Marlène , Marcel Frédérique , Brouillet Arthur , Belliveau James , Geny Christian , Deforges Lionel , Malcus-Vocanson Carine , Armstrong Marilyn , Lyon-Caen Olivier , Mandrand Bernard , Dobránsky Tomás , Rieger François , Perron Hervé
Published: July 2002

In investigating a possible link between a novel retroviral agent (provisionally called MSRV), recently characterised in multiple sclerosis (MS), and the neuropathology of MS, it was found that there was a significant correlation between gliotoxicity and reverse transcriptase activity in monocyte/macrophage culture supernatants (MMCS) unique to MS patients. MMCS from healthy controls and patients with other neurological diseases did not display either gliotoxicity or reverse transcriptase activity. The observed gliotoxic effect was an initial, intermediate filament network disorganization and subsequent cell death which was specific to astrocytes and oligodendrocytes. The reverse transcriptase activity and MSRV‐specific RNA were observed during the first 2 weeks of culture in MMCS from patients with active MS. The further elucidation of the molecular form(s) of this gliotoxic factor and its original source may be crucial in elucidating important etiopathogenic mechanisms in MS.
Protection against oxidative damage of erythrocyte membrane by the flavonoid quercetin and its relation to iron chelating activity
Authors: Ferrali M , Signorini C , Caciotti B , Sugherini L , Ciccoli L , Giachetti D , Comporti M
Published: July 2002

Incubation of glutathione (GSH) depleted mouse erythrocytes with the oxidants phenylhydrazine, acrolein, divicine and isouramil resulted in the release of free iron and in lipid peroxidation and hemolysis. The addition of the flavonoid quercetin, which chelates iron and penetrates erythrocytes, resulted in remarkable protection against lipid peroxidation and hemolysis. The protection seems to be due to intracellular chelation of iron, since a semi‐stoichiometric ratio between released iron and the amount of quercetin necessary to prevent lipid peroxidation and hemolysis was found. Incubation of GSH depleted human erythrocytes with divicine and isouramil did not induce lipid peroxidation and hemolysis in spite of a substantial release of iron. However, divicine and isouramil produced alterations of membrane proteins, such as spectrin and band 3, as well as formation of senescent cell antigen. The addition of quercetin prevented these alterations.
Aspirin protects endothelial cells from oxidative stress – possible synergism with vitamin E
Authors: Podhaisky Hans-Peter , Abate Aida , Polte Tobias , Oberle Stefanie , Schröder Henning
Published: July 2002

A 24‐h incubation with hydrogen peroxide (0.65 mM) markedly reduced viability of cultured endothelial cells. Preincubation with aspirin (3–30 μM) protected endothelial cells from hydrogen peroxide‐induced toxicity and increased viability in a concentration‐dependent fashion by up to 64% of control. A similar protection was observed with d‐α‐tocopherol acetate (vitamin E, 3–30 μM). The cytoprotective effects of aspirin and vitamin E against hydrogen peroxide were overadditive suggesting different mechanisms of antioxidant action. In agreement with this, cytotoxicity induced by iron, the main catalyst of oxygen radical formation, was substantially reduced by aspirin but not vitamin E. These results show that aspirin protects endothelial cells from oxidative stress possibly via binding or chelation of free cytosolic iron. Moreover, a combination of aspirin and vitamin E might be useful for the prevention of endothelial injury in cardiovascular disease, e.g. during atherogenesis.
Site‐directed mutagenesis of the Proteus mirabilis glutathione transferase B1‐1 G‐site
Authors: Casalone Enrico , Allocati Nerino , Ceccarelli Ilaria , Michele Masulli  , Rossjohn Jamie , Parker Michael W , Di Ilio Carmine
Published: July 2002

In order to investigate the roles of near N‐terminus Tyr, Cys, and Ser residues in the activity of bacterial glutathione transferase (GSTB1‐1) site‐directed mutagenesis was used to replace the following residues: Tyr‐4, Tyr‐5, Ser‐9, Cys‐10, Ser‐11, and Ser‐13. The results presented here show that, unlike all other alpha, mu, pi, theta and sigma classes of glutathione transferases so far investigated, GSTB1‐1 does not utilise any Tyr, Ser or Cys residue to activate glutathione. These results also suggest that the bacterial glutathione transferases may require classification into their own class.
Direct formation of mixed micelles in the solubilization of phospholipid liposomes by Triton X‐100
Authors: López Olga , de la Maza Alfonso , Coderch Luisa , López-Iglesias Carmen , Wehrli Ernst , Parra Jose Luis
Published: July 2002

The vesicle to micelle transition which results in the interaction of the Triton X‐100 surfactant with phosphatidylcholine vesicles was studied by means of dynamic light scattering (at different reading angles) and by freeze‐fracture electron microscopy techniques. Vesicle solubilization was produced by the direct formation of mixed micelles without the formation of complex intermediate aggregates. Thus, vesicle to micelle transformation was mainly governed by the progressive formation of mixed micelles within the bilayer. A subsequent separation of these micelles from the liposome surface (vesicle perforation by the formation of surfactant‐stabilized holes on the vesicle surface) led to a complete solubilization of liposomes.
The isolated H4‐H5 cytoplasmic loop of Na,K‐ATPase overexpressed in Escherichia coli retains its ability to bind ATP
Authors: Obšil Tomáš , Mérola Fabienne , Lewit-Bentley Anita , Amler Evžen
Published: July 2002

The H4‐H5 loop of the α‐subunit of mouse brain Na,K‐ATPase was expressed and isolated from Escherichia coli cells. Using fluorescence analogues of ATP, this loop was shown to retain its capability to bind ATP. Isolation of a soluble H4‐H5 loop with the native ATP binding site is a crucial step for detailed studies of the molecular mechanism of ATP binding and utilisation.
Metabolism of 8‐iso‐prostaglandin F2α
Authors: Basu S
Published: July 2002

Tritium labelled (1.1 MBq/17.7 μg/kg) and unlabelled 8‐iso‐PGF2α (43 μg/kg) were administered intravenously to female rabbits and frequent blood and continuous urinary samples were collected up to 4 h. The total radioactivity was lost rapidly from the circulation. About 80% of the total radioactivity was found in urine within 4 h. The plasma half‐life of 8‐iso‐PGF2α is found to be 1 min at the distribution phase. The terminal elimination phase half‐life was about 4 min. At 1.5 min after administration 64%, 19% and 13% of the plasma radioactivity represented 8‐iso‐PGF2α, 15‐keto‐8‐iso‐PGF2α and β‐oxidised products, respectively. The values for 20‐min plasma were 5%, 2% and 88%. The radiochromatograms from 10 min–4 h urinary samples were dominated by more polar β‐oxidised products. α‐Tetranor‐15‐keto‐13,14‐dihydro‐8‐iso‐PGF2α was identified as a major urinary metabolite.Thus, 8‐iso‐PGF2α metabolises in the rabbit mainly to several degraded polar metabolites through dehydrogenation at C‐15, reduction of Δ13‐double bond and β‐oxidation, and excretes efficiently into the urine.
Saccharomyces cerevisiae mitochondria can synthesise FMN and FAD from externally added riboflavin and export them to the extramitochondrial phase
Authors: Pallotta Maria Luigia , Brizio Carmen , Fratianni Alessandra , De Virgilio Caterina , Barile Maria , Passarella Salvatore
Published: July 2002

Evidence is given that mitochondria isolated from Saccharomyces cerevisiae can take up externally added riboflavin and synthesise from it both flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) probably due to the existence of the mitochondrial riboflavin kinase already reported and the novel mitochondria FAD synthetase. Moreover Saccharomyces cerevisiae mitochondria can export the newly synthesised flavin derivatives to the extramitochondrial phase. This has been proven to take place with 1:1 stoichiometry with riboflavin decrease outside mitochondria, thus showing that flavin traffic occurs across the mitochondrial membranes.
Ecto‐ATP diphosphohydrolase/CD39 is overexpressed in differentiated human melanomas
Authors: Dzhandzhugazyan Karine N , Kirkin Alexei F , thor Straten Per , Zeuthen Jesper
Published: July 2002

Ecto‐ATPase activities of melanocytes and human melanoma cell lines differing in the stage of progression were compared. A dramatic increase in ecto‐ATPase activity above the level of normal melanocytes was demonstrated in the differentiated melanomas and was followed by a gradual decrease with tumor progression. The characteristics of this enzymatic activity were consistent with CD39/ecto‐ATP diphosphohydrolase (ATPDase) which was found to be the major ecto‐ATP‐hydrolysing enzyme in melanomas. Indeed, the expression of CD39 and the level of CD39 mRNA followed a similar pattern. Since CD39 is known to regulate homotypic adhesion and, supposedly, affects the disaggregation step, we suggest that overexpression of CD39 may enable tumor cells to reduce contacts with T‐lymphocytes and escape from immunological recognition.
Analysis of the putative role of 24‐carbon polyunsaturated fatty acids in the biosynthesis of docosapentaenoic (22:5n‐6) and docosahexaenoic (22:6n‐3) acids
Authors: Infante Juan P , Huszagh Virginia A
Published: July 2002

The recent literature on the putative involvement of a single cycle of peroxisomal β‐oxidation of 24:5n‐6 and 24:6n‐3 polyunsaturated fatty acids in the biosynthesis of the respective docosapentaenoic (22:5n‐6) and docosahexaenoic (22:6n‐3) fatty acids is critically reviewed. Present evidence suggests that in vitro data in support of the above proposition is an artifact of a low 2,4‐dienoyl‐CoA reductase activity due to depletion of NADPH resulting from incubation conditions. Kinetic studies with radiolabeled precursors in cell cultures have shown lower initial rates of labeling of 24:6n‐3 than that of 22:6n‐3, indicating that 24:6n‐3 is an elongation product of 22:6n‐3 rather than its precursor. Analysis of other literature data supports the proposal that 22:5n‐6 and 22:6n‐3 are synthesized in mitochondria via channeled carnitine‐dependent pathways involving separate n‐6‐ and n‐3‐specific desaturases. It is proposed that impaired peroxisomal function in some peroxisomal disorders is a secondary consequence of defective mitochondrial synthesis of 22:6n‐3; moreover, some disorders of peroxisomal β‐oxidation show normal or increased 22:5n‐6 concentrations, indicating that 22:5n‐6 is synthesized by independent desaturases without peroxisomal involvement.
The iridoid glucoside secologanin is derived from the novel triose phosphate/pyruvate pathway in a Catharanthus roseus cell culture
Authors: Contin Adriana , van der Heijden Robert , Lefeber Alfons W.M , Verpoorte Robert
Published: July 2002

Secologanin is the iridoid building block of the majority of the terpenoid indole alkaloids. In the biosynthesis of secologanin, mevalonate was considered to be the exclusive precursor of isopentenyl diphosphate. After [1‐13C]glucose feeding to a cell culture of Catharanthus roseus, its incorporation into secologanin was studied by 13C NMR spectroscopy. The data showed that the novel triose phosphate/pyruvate and not the mevalonate pathway was the major route for the biosynthesis of secologanin.
The mode of action of Y13‐259 scFv fragment intracellularly expressed in mammalian cells
Authors: Cardinale Alessio , Lener Matteo , Messina Samantha , Cattaneo Antonino , Biocca Silvia
Published: July 2002

The anti‐p21ras Y13‐259 single‐chain Fv fragment (scFv) neutralizes the activity of p21‐ras when intracellularly expressed in different systems. We have studied the mode of action of this inhibition in 3T3 K‐ras fibroblasts and demonstrated that (i) this antibody fragment is highly aggregating when cytoplasmically expressed and (ii) the p21‐ras antigen is sequestered in these aggregates in an antibody‐dependent manner. This co‐segregation leads to an efficient inhibition of DNA synthesis. These results suggest that an antigen can be diverted from its normal location inside the cells in an antibody mediated way, prospecting a new mode of action for intracellular antibodies in vivo.
RGD‐dependent growth of maize calluses and immunodetection of an integrin‐like protein
Authors: Labouré Anne-Marie , Faik Ahmed , Mandaron Paul , Falconet Denis
Published: July 2002

When maize calluses are grown in the presence of the RGD peptide, important morphological changes are observed indicating the presence of a likely RGD‐binding receptor. Polyclonal antibodies generated against the human β1 integrin subunit, the platelet integrin αIIbβ3 (P23) and antibodies specific for either the β3 platelet chain or the αIIb polypeptide cross‐react with glycoproteins in Western blot analyses. Immunoprecipitation assays indicate that this maize integrin‐like protein shares structural similarities with the animal αIIbβ3 complex. We also show that AcAt2, a polyclonal antibody raised against Arabidopsis proteins purified on an RGD column, interacts with a maize protein.
Proteasome inhibitors induce mitochondria‐independent apoptosis in human glioma cells
Authors: Kitagawa Hiroyuki , Tani Eiichi , Ikemoto Hideyasu , Ozaki Isao , Nakano Atsuhisa , Omura Satoshi
Published: July 2002

The proteasome inhibitors lactacystin and AcLLNal induced p53‐independent apoptosis in two human glioma cell lines, and the apoptosis was accompanied by up‐regulation of immunoreactive wild‐type p53, p21Waf1, Mdm2, and p27Kip1. Pretreatment with cycloheximide decreased the induction of cell death independently of p53 protein status, suggesting that the up‐regulation of short‐lived proteins is associated with proteasome inhibitor‐induced apoptosis. Caspase‐3‐like proteases were activated in the proteasome inhibitor‐mediated apoptosis, and the induction of cell death was inhibited more effectively in the presence of z‐VAD.fmk than in the presence of Ac‐DEVD.fmk, suggesting that caspases other than caspase‐3 are involved. Nonetheless, there were no significant alterations in levels of immunoreactive Bcl‐2, Bcl‐xL, Bax, Bad, and Bak, nor any evidence of cytochrome c release into cytosol and dissipation of ΔΨ
m. Thus, the proteasome inhibitor‐induced apoptosis is mediated by a mitochondria‐independent mechanism, and the once activated caspase‐3 does not cause the cytochrome c release and the ΔΨ
m disruption.
Kup is the major K+ uptake system in Escherichia coli upon hyper‐osmotic stress at a low pH
Authors: Trchounian Armen , Kobayashi Hiroshi
Published: July 2002

The K+ uptake was observed in washed cells of Escherichia coli, wild‐type, upon hyper‐osmotic stress at pH 5.5 when glucose was supplemented. This uptake had apparent a K
m of 0.58 mM and V
max of 0.10 μmol K+/min/mg protein. Such a K+ uptake was investigated using a mutant defective in Kdp and TrkA but with a functional Kup and a mutant defective in Kdp and Kup but having an active TrkA. The K+ uptake to reach the steady state level as well as the initial K+ influx rate in the first mutant were at least 3.5‐fold greater than these values with the second mutant and similar to those of the wild‐type. Such differences in the K+ uptake activity were correlated with K+ requirements for growth of these mutants. Moreover, the K+ uptake in the wild‐type was blocked by a protonophore (carbonyl cyanide m‐chlorophenylhydrazone). Valinomycin, arsenate and N,N′‐dicyclohexylcarbodiimide were not effective in changing the K+ uptake. It is suggested that Kup is the major K+ uptake system in E. coli upon hyper‐osmotic stress at a low pH.
Amino acid limitation regulates CHOP expression through a specific pathway independent of the unfolded protein response
Authors: Jousse Céline , Bruhat Alain , Harding Heather P , Ferrara Marc , Ron David , Fafournoux Pierre
Published: July 2002

The gene encoding CHOP (C/EBP‐homologous protein) is transcriptionally activated by many stimuli and by amino acid deprivation. CHOP induction was considered to be due to an accumulation of unfolded protein into the ER (unfolded protein response (UPR)). We investigate the role of the UPR in the induction of CHOP by amino acid deprivation and show that this induction is not correlated with BiP expression (an UPR marker). Moreover, amino acid deprivation and UPR inducers regulate the CHOP promoter activity using distinct cis elements. We conclude that amino acid deprivation does not activate the UPR and regulates CHOP expression through a pathway that is independent of the UPR.
The RNA polymerase II core subunit 11 interacts with keratin 19, a component of the intermediate filament proteins
Authors: Bruno Tiziana , Corbi Nicoletta , Di Padova Monica , De Angelis Roberta , Floridi Aristide , Passananti Claudio , Fanciulli Maurizio
Published: July 2002

We have previously cloned the human RNA polymerase II subunit 11, as a doxorubicin sensitive gene product. We suggested multiple tasks for this subunit, including structural and regulatory roles. With the aim to clarify the human RNA polymerase II subunit 11 function, we have identified its interacting protein partners using the yeast two‐hybrid system. Here, we show that human RNA polymerase II subunit 11 specifically binds keratin 19, a component of the intermediate filament protein family, which is expressed in a tissue and differentiation‐specific manner. In particular, keratin 19 is a part of the nuclear matrix intermediate filaments. We provide evidence that human RNA polymerase II subunit 11 interacts with keratin 19 via its N‐terminal α motif, the same motif necessary for its interaction with the human RNA polymerase II core subunit 3. We found that keratin 19 contains two putative leucine zipper domains sharing peculiar homology with the α motif of human RNA polymerase II subunit 3. Finally, we demonstrate that keratin 19 can compete for binding human RNA polymerase II subunit 11/human RNA polymerase II subunit 3 in vitro, suggesting a possible regulatory role for this molecule in RNA polymerase II assembly/activity.
Interleukin 2‐Bax: a novel prototype of human chimeric proteins for targeted therapy
Authors: Aqeilan Rami , Yarkoni Shai , Lorberboum-Galski Haya
Published: July 2002

During the past few years many chimeric proteins have been developed to target and kill cells expressing specific surface molecules. Generally, these molecules carry a bacterial or plant toxin that destroys the unwanted cells. The major obstacle in the clinical application of such chimeras is their immunogenicity and non‐specific toxicity. We have developed a new generation of chimeric proteins, taking advantage of apoptosis‐inducing proteins, such as the human Bax protein, as novel killing components. The first prototype chimeric protein, IL2‐Bax, directed toward IL2R‐expressing cells, was constructed, expressed in Escherichia coli and partially purified. IL2‐Bax increased the population of apoptotic cells in a variety of target T cell lines, as well as in human fresh PHA‐activated lymphocytes, in a dose‐dependent manner and had no effect on cells lacking IL2R expression. The IL2‐Bax chimera represents an innovative approach for constructing chimeric proteins comprising a molecule that binds a specific cell type and an apoptosis‐inducing protein. Such new chimeric proteins could be used for targeted treatment of human diseases.
Peroxynitrite‐mediated oxidation of fibrinogen inhibits clot formation
Authors: Lupidi G. , Angeletti M. , Eleuteri A.M. , Tacconi L. , Coletta M. , Fioretti E.
Published: July 2002

The clotting activity of human fibrinogen was fully inhibited in vitro by peroxynitrite. The decrease of activity followed an exponential function and the concentration of peroxynitrite needed to inhibit 50% of fibrinogen clotting was 22 μM at 25°C. The oxidative modification(s) induced by the peroxynitrite system (i.e. ONOO−, ONOOH and ONOOH*) appeared specifically to affect fibrin clot formation (through the inhibition of fibrinogen polymerization) since the interaction of peroxynitrite‐modified fibrinogen with thrombin appeared to be unaffected. The addition of NaHCO3 decreased the peroxynitrite effect on fibrinogen clotting, suggesting that the reactive species formed by the reaction of CO2 with peroxynitrite are less efficient oxidants of peroxynitrite itself. Similar effects were observed after addition of bilirubin, which also exerted a significant protection against peroxynitrite‐mediated modification of fibrinogen.
H+‐PPases: a tightly membrane‐bound family
Authors: Baltscheffsky Margareta , Schultz Anders , Baltscheffsky Herrick
Published: July 2002

The earliest known H+‐PPase (proton‐pumping inorganic pyrophosphatase), the integrally membrane‐bound H+‐PPi synthase (proton‐pumping inorganic pyrophosphate synthase) from Rhodospirillum rubrum, is still the only alternative to H+‐ATP synthase in biological electron transport phosphorylation. Cloning of several higher plant vacuolar H+‐PPase genes has led to the recognition that the corresponding proteins form a family of extremely similar proton‐pumping enzymes. The bacterial H+‐PPi synthase and two algal vacuolar H+‐PPases are homologous with this family, as deduced from their cloned genes. The prokaryotic and algal homologues differ more than the H+‐PPases from higher plants, facilitating recognition of functionally significant entities. Primary structures of H+‐PPases are reviewed and compared with H+‐ATPases and soluble PPases.
The gap between evidence and practice in maternal healthcare
Authors: Villar J. , Carroli G. , Gülmezoglu A.M.
Published: July 2002

The expected improvement in maternal and perinatal health in developing countries has not yet materialized. In addition to the factors related to socioeconomic conditions, we have identified areas where large gaps between evidence and practice are apparent. These gaps are in clinical care, implementation of effective practices and in selecting research priorities. We present examples from our own research and the literature to illustrate these points.
Neonatal gastric aspirates as a predictor of perinatal hepatitis B virus infections
Authors: Chen W.‐H. , Yin C.‐S. , Chang Y.‐K. , Yan J.‐S. , Chu M.‐L.
Published: July 2002

Objective: To elucidate possible routes and predictors of perinatal transmission of hepatitis B virus (HBV). Method: This was a prospective follow‐up study. One hundred and forty‐seven out of 1762 pregnant women who were screened in the antenatal clinic of a university teaching hospital were HBsAg carriers. Enzyme immunoassay was used for determination of hepatitis B markers. Occurrence of HBsAg in newborns' gastric aspirates, newborns' and infants' blood, and maternal milk samples were determined. Their relationship with delivery routes and duration of the first stage of labor were analyzed by chi square test. Results: The presence of HBsAg in newborns' gastric aspirates was strongly associated with the acquisition of HBsAg by the babies. There was no correlation between the rate of infant antigenemia and the duration of the first stage of labor, nor did cesarean section decrease the rate of vertical transmission of HBV. Conclusions: This is the first report to provide direct evidence for the major role of the oral route in vertical transmission of HBV during delivery. In addition to maternal serum HBeAg, HBsAg status in newborn's gastric aspirates is another important determinant for vertical transmission of HBV.
Pre‐eclampsia and eclampsia associated with increased lipid peroxidation and decreased serum vitamin E levels
Authors: Yanik F.F , Amanvermez R , Yanik A , Çelik C , Kökçü A
Published: July 2002

Objective: To evaluate lipid peroxidation and the serum levels of the antioxidant vitamin E in pre‐eclampsia according to the disease severity. Method: Serum malondialdehyde (MDA) and vitamin E levels were measured in 18 pre‐eclamptic, 15 eclamptic and 25 normotensive pregnant women in Ondokuz Mayis University Hospital. The correlation of these levels with the factors indicating disease severity was tested. Mann–Whitney U‐test and correlation coefficients were used for the statistical analysis. Result: Both the pre‐eclamptic and the eclamptic patients had higher MDA and lower vitamin E levels compared with control (P<0.05); but these values were not significantly different from each other (P>0.05). MDA levels were significantly correlated with the systolic and diastolic blood pressure (BP) and with serum uric acid levels. There was significant but negative correlation with the vitamin E levels. Conclusion: There is an imbalance between lipid peroxidation and serum vitamin E levels in pre‐eclampsia and eclampsia. Increased lipid peroxidation is well correlated with the increase in systolic and diastolic BP measurements and serum uric acid levels.
On theory in operations management
Authors: Schmenner Roger W , Swink Morgan L
Published: July 2002

The field of operations management has been criticized for the inadequacy of its theory. We suggest that this criticism may be too harsh, and further, that many building blocks of theory are prevalent in the body of existing research. This paper has two goals. The first is to suggest that careful organization of our thinking can lead to useful, productive theories in operations management that demonstrate all the hallmarks of the familiar theories of natural science. We discuss the nature of scientific inquiry in general terms, and examine the implications for what should be expected from theory in operations management. Our second goal is to illustrate through examples how such theories and their related laws might be developed. Two theories are proposed: the Theory of Swift, Even Flow, and the Theory of Performance Frontiers. The Theory of Swift, Even Flow addresses the phenomenon of cross‐factory productivity differences. The Theory of Performance Frontiers addresses the multiple dimensions of factory performance and seeks to unify prior statements regarding cumulative capabilities and trade‐offs. Implications drawn from the theories are discussed and concluding remarks suggest the advantages of future theory development and test.
A review of operations management studies using scale development techniques
Authors: Hensley Rhonda L
Published: July 2002

Operations management research is beginning to focus on the development and use of reliable and valid scales. OM scale development efforts and scale development in organizational behavior and psychology are compared. Major differences include the fact that OM research tended, until recently, to be theoretical and, when applied, tended to use the firm as a unit of measure. OM research, therefore, seems to lack a common language that other fields have developed. OM literature was searched for completely described scale development efforts, and six studies were identified and reviewed for this paper. Suggested techniques of scale development were compiled primarily from those methods used in research areas such as psychology, organizational behavior, and management. The reviewed studies were compared to the suggested techniques. Many of the same techniques were described by the six studies. The similarities should be encouraging to researchers thinking about scale development studies. Weaknesses in the studies are identified, and suggestions for researchers are presented. Finally, the study provides a discussion of when and why OM researchers might find the development and use of scales advantageous in their research efforts.
Supply management orientation and supplier/buyer performance
Authors: Shin Hojung , Collier David A , Wilson Darryl D
Published: July 2002

Academics and practitioners agree that excellence in supply management results in better quality, customer service, and channel performance. Yet, most of these studies are either conceptual in nature or actual case studies. The primary objective of this research is to test the impact of a supply management orientation (SMO) on the suppliers' operational performance and buyers' competitive priorities (cost, quality, delivery, flexibility). Three major research hypotheses associated with SMO, Supplier Performance (SP), and Buyer Performance (BP) are tested using a confirmatory structural equation modeling approach. The results of this research support the conclusion that an improvement (increase) in the SMO improves both the suppliers' and buyers' performance (i.e., a win–win situation for the supply chain). In addition, the influence of SMO on delivery‐ and quality‐related performance is more statistically significant than on cost or flexibility performance. In fact, when volume and process flexibility are top competitive priorities, a supply chain management orientation may not be an effective way to achieve the desired flexibility. The article ends by discussing other conclusions and suggests directions for future research.
Regional variations in certain cellular characteristics in human lumbar intervertebral discs, including the presence of α‐smooth muscle actin
Authors: Hastreiter Dawn , Ozuna Richard M. , Spector Myron
Published: July 2002

An evaluation of the regional variation of certain cellular features in the human intervertebral disc (IVD) could lead to a better understanding of site‐specific properties relative to degradation, response to injury, and healing processes. The objective of this study was to determine how cell density, cell morphology, cell grouping, and expression of a specific actin isoform varied with location and degeneration in the human disc. A total of 41 human L4‐L5 and L5‐S1 discs removed postmortem from 21 individuals were analyzed. The discs were graded for degeneration based on the Thompson scale and processed for evaluation. Microtomed sections from paraffin‐embedded specimens were stained with hematoxylin and eosin or a monoclonal antibody to α‐smooth muscle actin (α‐SMA), an actin isoform often associated with contraction. A significant regional dependence was found for most of the measured parameters. A fourfold increase in cell density was found in proceeding from the nucleus pulposus (NP) to the outer annulus (OA) of the IVD. Approximately 30% of the cells in the NP were present in groups. Virtually all of the cells in the NP and 40% of those in the OA were round. Moreover, notable percentages (12–15%) of the cells in the NP and inner annulus (IA) contained α‐SMA. Only pair density was found to be correlated with Thompson grade, with more degenerated specimens having higher values. A greater effect was also observed on the percentage of cells in groups. These findings provide the basis for future work to investigate the importance of cells in groups, the role of α‐SMA in the disc, and the changes in these cellular characteristics in pathological disc conditions. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Isolation of RNA from small human articular cartilage specimens allows quantification of mRNA expression levels in local articular cartilage defects
Authors: Gehrsitz Angelika , McKenna Louise A. , Söder Stefan , Kirchner Thomas , Aigner Thomas
Published: July 2002

Human adult cartilage is an inherently difficult tissue from which to isolate RNA. The RNA isolation techniques described so far have generally only been successfully applied to the isolation of RNA from larger amounts of cartilage. However, it is important to be able to analyse focal cartilage lesions in order to understand the local processes in the cartilage degeneration process. Therefore, we have developed a protocol for isolating RNA directly from as little as 10 mg wet weight of cartilage followed by quantitative PCR analysis. We were able to analyse the expression levels of several genes in parallel including aggrecan and type II collagen. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Point prevalence of schizophrenia in immigrant groups in Rotterdam: data from outpatient facilities
Authors: Schrier A.C. , van de Wetering B.J.M. , Mulder P.G.H. , Selten J.P.
Published: July 2002

Objective

Reports of an increased incidence of schizophrenia in some immigrant groups to The Netherlands are based exclusively on hospital data. The aims of our study were: 1) to determine the treated point prevalence of schizophrenia at outpatient mental health services in Rotterdam and to compare the results for immigrants to those for natives; and 2) to compare groups born in The Netherlands and immigrant groups in terms of the proportions of patients with a previous hospital admission.

Method

We included all patients aged between 20 and 64 who were treated for a non-affective psychosis at any of the outpatient mental health services in Rotterdam on October 1, 1994. The mental health professionals responsible reported on the socio-demographic and clinical characteristics of each patient.

Results

Seven hundred and thirteen patients with a diagnosis of schizophrenia (DSM-III-R) were identified (rate: 2.1 per 1000). The (treated) prevalence of schizophrenia in male immigrants from Surinam and Morocco and in female immigrants from Surinam, the Netherlands Antilles and Cape Verde was significantly higher than that in their native-born counterparts (odds ratios between 2 and 3). The (treated) prevalence was not significantly higher in immigrants from Turkey, female immigrants from Morocco or male immigrants from the Antilles. Proportions of patients with a previous hospital admission were similar in each ethnic group (81–93%).

Conclusion

These findings are generally in line with earlier studies, based on the Dutch psychiatric registry, which has reported an increase in the (treated) incidence of schizophrenia in immigrants from Surinam and the Netherlands Antilles and in male immigrants from Morocco, and no increase in the (treated) incidence in immigrants from Turkey or female immigrants from Morocco.
Season of birth, gender and negative symptoms in schizophrenia
Authors: Troisi A. , Pasini A. , Spalletta G.
Published: July 2002

The aim of this study was to ascertain whether the symptom profile distinguishes between schizophrenic patients born in the winter and early spring and those born in other seasons. The sample consisted of 204 patients with a DSM-III-R diagnosis of schizophrenia who had been hospitalized for acute psychotic decompensation. Symptom ratings were based on the Positive and Negative Syndrome Scale (PANSS). The use of demographic and anamnestic data as dependent variables did not detect any season-of-birth effect. In contrast, clear gender-specific differences emerged from the comparison focusing on symptom dimensions and clinical subtype. Female patients born in the winter and early spring had higher scores on the PANSS negative scale and anergia factor whereas male patients born in other seasons had higher scores on the PANSS anergia factor. In addition, we found a gender-specific association between season of birth and clinical subtype. Most paranoid female patients were born in the non-winter months whereas, among men, a slightly higher percentage of paranoid patients were born in winter months. These results suggest that gender plays a role in modulating the effect of the season of birth on symptoms of schizophrenia.
The effects of trazodone on sleep disturbances induced by brofaromine
Authors: Haffmans PMJ , Vos MS
Published: July 2002

The effects of trazodone on subjective and objective sleep parameters were compared to those of placebo in a double-blind design in seven patients who developed insomnia during treatment with the selective and reversible MAO-A inhibitor, brofaromine. Trazodone significantly increased deep sleep and altered the architecture of sleep in these patients. Subjectively, patients reported a better and deeper sleep. No negative interactions between brofaromine and trazodone were observed and side-effects were minimal. A low dose of trazodone may be a safe and effective agent in the treatment of MAO-I induced insomnia.
PRIMARY CARE IN NURSE‐MIDWIFERY PRACTICE: A NATIONAL SURVEY
Authors: Stuart Deborah , Oshio Sachiko
Published: July 2002

Providing primary health care is a relatively new addition to the scope of practice for certified nurse‐midwives (CNMs)/certified midwives (CMs); thus, not much is known about how this component has been integrated into midwifery practice. The purpose of this descriptive study was to examine the type and extent of primary care education among CNMs/CMs and how various common health conditions are managed. In addition, perceptions of barriers to incorporating primary care into their practice were gathered. A small national survey was conducted among randomly selected members of the American College of Nurse‐Midwives. No CMs participated. Although the sample size (n = 63) precludes generalizing the findings, 65% of CNMs reported lack of formal education in primary care. However, when asked about specific health conditions, more than 50% stated that they had some form of education in treating 30 of 37 common health problems. It is noteworthy that 54% of the CNM respondents indicated that they do not provide newborn care despite the fact that more than 85% of them received newborn education. Barriers such as lack of insurance reimbursement, institutional rules, and a lack of understanding of the CNM's scope of practice were cited by respondents as contributing factors. Unfamiliarity with primary care may be the most important factor in the reluctance of CNMs to incorporate primary care into practice.
Plasma concentrations of active lovastatin acid are markedly increased by gemfibrozil but not by bezafibrate
Authors: Kyrklund Carl , Backman Janne T. , Kivistö Kari T. , Neuvonen Mikko , Laitila Jouko , Neuvonen Pertti J.
Published: July 2002

Background

Concomitant use of fibrates with statins has been associated with an increased risk of myopathy, but the underlying mechanism of this adverse reaction remains unclear. Our aim was to study the effects of bezafibrate and gemfibrozil on the pharmacokinetics of lovastatin.

Methods

This was a randomized, double‐blind, 3‐phase crossover study. Eleven healthy volunteers took 400 mg/day bezafibrate, 1200 mg/day gemfibrozil, or placebo for 3 days. On day 3, each subject ingested a single 40 mg dose of lovastatin. Plasma concentrations of lovastatin, lovastatin acid, gemfibrozil, and bezafibrate were measured up to 24 hours.

Results

Gemfibrozil markedly increased the plasma concentrations of lovastatin acid, without affecting those of the parent lovastatin compared with placebo. During the gemfibrozil phase, the mean area under the plasma concentration–time curve from 0 to 24 hours [AUC(0–24)] of lovastatin acid was 280% (range, 131% to 1184%; P < .001) and the peak plasma concentration (Cmax) was 280% (range, 123% to 1042%; P < .05) of the corresponding value during the placebo phase. Bezafibrate had no statistically significant effect on the AUC(0–24) or Cmax of lovastatin or lovastatin acid compared with placebo.

Conclusions

Gemfibrozil markedly increases plasma concentrations of lovastatin acid, but bezafibrate does not. The increased risk of myopathy observed during concomitant treatment with statins and fibrates may be partially of a pharmacokinetic origin. The risk of developing myopathy during concomitant therapy with lovastatin and a fibrate may be smaller with bezafibrate than with gemfibrozil.

Clinical Pharmacology & Therapeutics (2001) 69, 340–345; doi: 10.1067/mcp.2001.115542
Rab44 isoforms similarly promote lysosomal exocytosis, but exhibit differential localization in mast cells
Authors: Kadowaki Tomoko , Yamaguchi Yu , Ogawa Kohei , Tokuhisa Mitsuko , Okamoto Kuniaki , Tsukuba Takayuki
Published: February 2021

Rab44 is a large Rab GTPase containing a Rab GTPase domain and some additional N‐terminal domains. We recently used Rab44‐deficient mice to demonstrate that Rab44 regulates granule exocytosis in mast cells and IgE‐mediated anaphylaxis. In mouse mast cells, Rab44 is expressed as two isoforms, namely, the long and short forms; however, the characteristics of these two isoforms remain unknown. Here, we investigated secretion and localization of the human long Rab44 isoform and the two mouse isoforms and their mutants expressed in rat basophilic leukemia (RBL)‐2H3 cells. Expression of the human long isoform and both mouse isoforms caused an increase in β‐hexosaminidase secretion. Confocal and quantitative analyses showed that both human and mouse long isoforms localized mainly to lysosomes while the mouse short isoform localized mainly to the ER. Live imaging with LysoTracker indicated that the size and number of LysoTracker‐positive vesicles were altered by the various mutants. Ionomycin treatment partially altered localization of both long isoforms to the plasma membrane and cytosol, whereas it had little effect on colocalization of the short isoform with lysosomes. Mechanistically, both human and mouse Rab44 proteins interacted with vesicle‐associated membrane protein 8 (VAMP8), a v‐SNARE protein. Therefore, Rab44 isoforms similarly promote lysosomal exocytosis, but exhibit differential localization in mast cells.