bluuebunny/crossref_metadata_2025_split huggingface dataset:
THERAPEUTIC STRATEGIES FOR THE INHIBITION OF INDUCIBLE NITRIC OXIDE SYNTHASE—POTENTIAL FOR A NOVEL CLASS OF ANTI‐INFLAMMATORY AGENTS
Authors: PFEILSCHIFTER JOSEF , EBERHARDT WOLFGANG , HUMMEL RICHARD , KUNZ DIETER , MÜHL HEIKO , NITSCH DOROTHEA , PLÜSS CHRISTOPH , WALKER GABY 
Published: September 2002

AbstractIn recent years, NO, a gas previously considered a potentially toxic chemical, has become established as a diffusible universal messenger mediating cell—cell communication throughout the body. In mammals, NO is a recognized mediator of blood vessel relaxation that helps to maintain blood pressure. In the central nervous system NO acts as a non‐conventional neurotransmitter and participates in the establishment of long‐term plasticity required for memory formation. In addition, NO is responsible for some parts of the host response to sepsis and inflammation and contributes to certain disease states. A number of strategies have emerged with regard to a pharmacological control of pathological NO overproductions. This review will discuss these novel therapeutic approaches that may provide new means for clinical medicine.
BREFELDIN A DISTORTS DISCOID AND POLARIZED MORPHOLOGICAL ORGANIZATIONS OF EPITHELIAL CELLS IN CULTURE
Authors: PRIGOZINA N. L. , DUGINA V. B. , VASILIEV J. M. 
Published: September 2002

AbstractBrefeldin A (BFA), an agent disorganizing organelle traffic, was used to find out the role of this traffic in the maintenance of shape and cytoskeletal organization of cultured epithelial MDCK cells. Cell shape was assessed using dispersion and elongation indices (Dunn and Brown, 1986,J Cell Sci83: 313–340). BFA reversibly transformed discoid MDCK cells with circular actin pattern into moderately polarized cells with straight actin bundles. In other experiments the same MDCK cells were first transformed into highly polarized fibroblast‐like cells by incubation with ‘scatter factor’ (HGF/SF) and then treated with BFA. In these conditions BFA significantly decreased the degree of polarization. It is suggested that both highly polarized and discoid morphological organizations are controlled by organelle traffic.
DEMONSTRATION OF ALKALINE PHOSPHATASE PARTICIPATION IN THE MINERALIZATION OF OSTEOBLASTS BY ANTISENSE RNA APPROACH
Authors: TORII YASUYOSHI , HITOMI KIYOTAKA , YAMAGISHI YASUKO , TSUKAGOSHI NORIHIRO 
Published: September 2002

AbstractMC3T3‐E1 cells grown with ascorbic acid express sequentially osteoblastic marker proteins such as alkaline phosphatase (ALPase) and then form a mineralized extracellular matrix (ECM) as a consequence of osteoblastic differentiation. To explore the functional roles of ALPase in the process of osteoblastic maturation, an inducible expression vector for antisense ALPase RNA was constructed and stably transfected into MC3T3‐E1 cells. The expression of antisense ALPase RNA in the differentiated MC3T3‐E1 transfectants reduced markedly the ALPase activity, which resulted in a significant decrease in the deposition of minerals upon prolonged culture. These findings demonstrated directly that ALPase participated in the mineralizationof ECM.
INTEGRIN SYNTHESIS AND UTILIZATION IN CULTURED HUMAN OSTEOBLASTS
Authors: PISTONE M. , SANGUINETI C. , FEDERICI A. , SANGUINETI F. , DEFILIPPI P. , SANTOLINI F. , QUERZÉ G. , MARCHISIO P. C. , MANDUCA P. 
Published: September 2002

AbstractThis study describes the adhesion of human osteoblasts, culturedin vitro, to proteins of the extracellular matrix, the biosynthesis of integrins, their topography and organization in focal contacts. The adhesion of osteoblasts to laminin, type I collagen, vitronectin and fibronectin was 77–100%, in 2h and at 55nmsubstrata concentration, and it was accompained by spreading of the cells. Adhesion to fibronectin (FN), laminin (LN) and type I collagen (COL) was inhibited by antibodies to the β1 integrin and antibodies to the α5 chain affected adhesion only to fibronectin. Using a panel of polyclonal antibodies against α2, α3, α5, αv, β1 andβ3 integrins we detected synthesis of α3β1, α5β1, αvβ3, and an αvβ1‐like dimer by immunoprecipitation of metabolically labelled cell lysates. Studies of immunolocalization demonstrated the presence of the same integrins identified in lysates, plus α4, α1 and β5 subunits. In cells adhering in the presence of serum we showed organization of β3 and αv integrins in focal contacts. In cells adhering to fibronectin α5 and β1 integrins were localized in focal contacts. In cells spread on laminin or type I collagen none of the integrins investigated was localized in focal contacts.
EXPRESSION AND CELLULAR LOCALIZATION OF THE mRNA FOR THE 25‐kDa HEAT‐SHOCK PROTEIN IN THE MOUSE
Authors: WAKAYAMA TOMOHIKO , ISEKI SHOICHI 
Published: September 2002

ABSTRACTThe 25‐kDa heat‐shock protein (Hsp25) is a member of the small heat‐shock protein family but its function remains largely unknown. In the present study we examined the expression and cellular localization of Hsp25 mRNA in mice under physiological, unstressed conditions using Northern blot and in situ hybridization analyses with specific oligonucleotide probes. At the organ level, high amounts of Hsp25 mRNA were detected in the oesophagus, skin, eye, stomach, lung and urinary bladder, with moderate amounts in the heart, skeletal muscle, aorta, adrenal gland, ovary, testis, uterus, large intestine, and thymus. At the cellular level, intense to moderate signals for Hsp25 mRNA were localized in the muscle cells of smooth, heart and skeletal types, in the epithelial cells of stratified squamous and transitional types and of the oviduct, in the steroid endocrine cells of the adrenal cortex and corpus luteum, as well as in the spermatocytes of the testis. In contrast, the signal was scarcely detectable in the nervous tissues, lymphatic tissues, the columnar epithelial cells of the digestive tract, or the parenchymal cells of the liver, pancreas and kidney. These results suggest some significant role for Hsp25 in distinct populations of mouse cells under physiological conditions.
THE TETRAHYMENA HOMOLOG OF BACTERIAL AND MAMMALIAN 4‐HYDROXYPHENYLPYRUVATE DIOXYGENASES LOCALIZES TO MEMBRANES OF THE ENDOPLASMIC RETICULUM
Authors: Neve Søren , Tornehave Ditte , Corydon Thomas Juhl , Kristiansen Karsten 
Published: September 2002

AbstractThe expression and intracellular localization of the Tetrahymena homolog of 4‐hydroxyphenylpyruvate dioxygenase (HPPD) were investigated in wild‐type Tetrahymena thermophila strain B1868 VII and the mutant strains IIG8, defective in food vacuole formation, MS‐1, blocked in secretion of lysosomal enzymes, and SB 281, defective in mucocyst maturation. Immunoelectron microscopy and confocal laser scanning microscopy demonstrated that Tetrahymena HPPD primarily localized to membranes of the endoplasmic reticulum. In addition, Tetrahymena HPPD was detected in association with membranes of the Golgi apparatus, and transport vesicles in exponentially growing wild‐type and mutant strains. In starved cells, Tetrahymena HPPD localized exclusively to membranes of small vesicles. Since no de novo synthesis ofTetrahymena HPPD takes place in cells starved for more than 30min, these results suggest that there is a flow ofTetrahymena HPPD from the endoplasmic reticulum to small vesicles, possibly via the Golgi apparatus, and thatTetrahymena HPPD contains a signal for vesicle membrane retrieval or retention.
ANNEXIN V RELOCATES TO THE PERIPHERY OF ACTIVATED PLATELETS FOLLOWING THROMBIN ACTIVATION: AN ULTRASTRUCTURAL IMMUNOHISTOCHEMICAL APPROACH
Authors: Tzima Eleni , POUJOL Christel , Nurden Paquita , Nurden Alan T. , Orchard Margaret A. , Walker John H. 
Published: September 2002

AbstractWe have previously shown biochemically that the physiological agonist thrombin can cause translocation of endogenous annexin V to a fraction containing all platelet membranes. This paper reports ultrastructural immunohistochemical data revealing that annexin V molecules localize with plasma membranes of blood platelets following thrombin activation. When ultrathin sections of resting platelets were examined by immunogold staining, annexin V was found to be cytosolic, having a generalized distribution throughout the platelet. After thrombin activation, annexin V became peripheral in location and plasmalemma association increased. Morphometric analysis of gold particles shows that annexin V relocates specifically to the plasma membrane and its underlying cytoskeleton following treatment with thrombin. In control platelets 6.1%±0.78 of annexin V is present at the plasma membrane and 15.0%±0.82 in the region corresponding to the membrane cytoskeleton (10–80nm); after stimulation with 0.5unit/ml thrombin for 2min this increased to 16.7%±0.22 and 40.4%±0.53, respectively.
DEVELOPMENTAL REGULATION OF GRANULE SIZE AND NUMBERS IN LARVAL SALIVARY GLANDS OF DROSOPHILA BY STEROID HORMONE ECDYSONE
Authors: Farkaš Robert , Šuáková Gabriela 
Published: September 2002

AbstractThe size and number of secretory granules in late larval salivary glands of Drosophila melanogaster have been related to interecdysial and early metamorphic development represented by well‐known puffs in polytene chromosomes. Interecdysial period (puff stage 1 (PS1)) is characterized by presence of numerous small granules (11,000 per cell). The transition from PSI to early metamorphic phase (PS2 and upwards), induced by rapid elevation in endogenous steroid hormone ecdysone, is accompanied by continuous growth of granule diameter with concomitant reduction in their number per cell. In the PS4, just prior to secretion, ∼3000 mature granules occur per cell. The mature state is associated with the change from hyperbolic to Gaussian distribution of granule number over their size range. Similar changes in secretory granule parameters were observed in interecdysial salivary glands explanted from 3rd instar larvae and cultured in vitro in medium containing 5×10−6m ecdysone.
LOCALIZATION OF β‐ENDORPHIN IN TETRAHYMENA BY CONFOCAL MICROSCOPY. INDUCTION OF THE PROLONGED PRODUCTION OF THE HORMONE BY HORMONAL IMPRINTING
Authors: Csaba G. , Kovács P. 
Published: September 2002

AbstractThe unicellular Tetrahymena has hormone receptors and hormones which are characteristic of higher vertebrates, as well as similar signal transduction pathways. In the present experiments, immunocytochemistry and confocal microscopy were used to study the presence and localization of β‐endorphin in Tetrahymena pyriformis GL. Endorphin (or endorphin‐like material) was localized in the cortical structures, oral field, cilia and nuclear envelope. One‐hour treatment with β‐endorphin (‘hormonal imprinting’) increased the presence of immunocytochemically demonstrable endorphin immediately and after 24h, and was especially strong after 96h of treatment. Simultaneous treatment with naloxone, an opioid antagonist, did not inhibit endorphin effect, but had an additive effect on endorphin production. Naloxone alone induced a very intensive accumulation of endorphin 96h after treatment. The results support the possibility of a hormone production being induced by the imprinting procedure, but the imprinter‐like effect of naloxone also points to the importance in this case of non‐discriminatory receptors also being involved in the process.
HELICAL EXTRUSIONS AT THE NUCLEAR ENVELOPE: POSSIBLE INVOLVEMENT IN NUCLEOCYTOPLASMIC TRAFFICKING
Authors: Wheatley Denys N. 
Published: September 2002

AbstractThe existence of intracytoplasmic helical inclusion 24h after serum stimulation of 3T3 cells which had previously been serum deprived (0.2%) for 2 days has been previously reported. Further evidence of their relationship with nuclear pores has been found, and their involvement in nucleocytoplasmic transport seems more probable. Helical formations resembling those originally seen have been found seemingly extruding from nuclear pores into the cytoplasm. However, it is unlikely that these structures contribute significantly to the translocation of material from the nucleus to the cytoplasm on a regular basis because their occurrence is rare. An association of the helical complexes with microfilaments has also been observed. Their relationship to annulate lamellae remain enigmatic.
THE EFFECTS OF EXHAUSTIVE EXERCISE ON THE ACTIVITY LEVELS OF CATALASE IN VARIOUS TISSUES OF MALE AND FEMALE RATS
Authors: Terblanche S. E. 
Published: September 2002

AbstractThe effects of exhaustive exercise on the activity levels of catalase (EC 1.11.1.6) in various tissues of male and female Sprague—Dawley rats (Rattus norvegicus) were investigated. Both the male and female rats were subdivided into an experimental group and a control group consisting of eight rats each. One group of each sex was subjected to a swimming session of 1h (experimental group) while the other group of each sex served as sedentary control groups. The tissues investigated were liver, heart, kidney and lung. The activity levels of catalase in all the tissues investigated were significantly (P< 0.05) elevated in both male and female rats as a result of exercise. The average increase in the activity levels of catalase in the various tissues investigated for both male and female rats was 417% (males 404%; females 430%). The male and female rats exhibited comparable activity levels of catalase in all the tissues investigated. The higher activity levels of catalase as a result of exercise might be indicative of a compensatory measure to counteract the possible detrimental effects associated with oxidative stress.
VARIABILITY IN E‐SELECTIN EXPRESSION, mRNA LEVELS AND sE‐SELECTIN RELEASE BETWEEN ENDOTHELIAL CELL LINES AND PRIMARY ENDOTHELIAL CELLS
Authors: Galley H.F , Blaylock M.G , Dubbels A.M , Webster N.R 
Published: September 2002

AbstractEndothelial cell lines express markers and are assumed to exhibit other endothelial cell responses. We investigated E‐selectin expression from human umbilical vein endothelial cells, the spontaneously transformed ECV304 line and the hybrid line EA.hy926 by flow cytometry and immunofluorescence, mRNA and soluble E‐selectin release. In cells exposed to tumour necrosis factor α (TNF‐α) and interleukin‐1β (IL‐1β), median (range) percentage of E‐selectin‐positive HUVECs increased from 1.6(0.9–6.2)% to 91.4(83.0–96.1)%, (P=0.001) using flow cytometry. In contrast, E‐selectin expression by ECV304 and EA.hy926 cell lines was 100‐fold lower. E‐selectin mRNA was detectable after 2h, maximal at 6h in HUVECs and undetectable in EA.hy926 and ECV304 cell lines after exposure to TNF‐α/IL‐1β. sE‐selectin accumulation increased (P=0.004) in HUVECs only. Neutrophil adherence to ECV304 and EA.hy926 cells was poor compared to HUVECs (P=0.004). The cell lines ECV304 and EA.hy926 do not exhibit normal endothelium expression of E‐selectin, and may not be appropriate for studies of adhesion.
RESTING CYST WALL GLYCOPROTEINS ISOLATED FROM TWO COLPODID CILIATES ARE GLYCINE‐RICH PROTEINS
Authors: Izquierdo Adriana , Martín‐González Ana , Gutiérrez Juan Carlos 
Published: September 2002

AbstractTwo glycoproteins bands isolated from the cyst wall protein pattern of two colpodid ciliates,Colpoda inflata (gp46CI) and Colpoda cucullus (gp46CC) were analysed for their amino acid composition. Both glycoproteins are very rich in glycine and have a relatively high hydrophobicity, containing additionally many leucine and alanine residues. Their high degree of similarity is both quantitative and qualitative. Compared with just two previously published reports, their amino acid compositions are similar to those found in the hydrolysed cyst wall total proteins from the ciliatesC. steinii and Paraurostyla spp. The amino acid composition corroborates that they are indeed glycoproteins, because asparagine, an amino acid residue suitable for the attachment to N‐acetylglucosamine by its amide group (N‐glycan), is abundant in both proteins. We discuss our data in relation to other glycine‐rich proteins and a comparison with amino acid composition protein databases is carried out.
INVOLVEMENT OF THE PROTEIN KINASE PATHWAY IN MELANIN SYNTHESIS BY CHICK RETINAL PIGMENT EPITHELIAL CELLS
Authors: Kishi Hiroko , Mishima Hiromu K. , Yamashita Uki 
Published: September 2002

AbstractProtein kinases are involved in a variety of cellular functions and cell proliferation in eyes. We have explored the involvement of protein kinase C (PKC) in cell proliferation and melanin synthesis by chick retinal pigment epithelial (RPE) cells in vitro. This was achieved by incubation of confluent RPE cells with known inhibitors of protein kinase, H‐7, W‐7, H‐8, and staurosporine. Chick RPE cells were cultured in the presence or absence of the protein kinase inhibitors for a 10‐day period. Effects of the inhibitors on cell proliferation and melanin synthesis, as an indication of cell differentiation, were assessed by counting the number of surviving cells and by measuring the melanin content in the cells, respectively. H‐7, W‐7, and staurosporine inhibited cell proliferation and increased melanin synthesis in a concentration‐dependent manner during culture; however, H‐8 did not produce these cellular effects. These findings indicate that PKC and calcium/calmodulin‐dependent kinase pathways are involved in the proliferation and differentiation of chick RPE cells.
CA2+MOBILIZATION IN THE HUMAN SUBMANDIBULAR DUCT CELL LINE A253
Authors: Andersson Charlotte , Zhang Ai‐Ling , Roomans Godfried M. 
Published: September 2002

AbstractCa2+mobilization induced by ATP, isoproterenol and the Ca2+‐ATPase inhibitor thapsigargin in the human submandibular duct cell line A253 was investigated using the Ca2+‐sensitive fluorescent indicator fura‐2. ATP and isoproterenol increased cytosolic free Ca2+([Ca2+]i) and subsequent exposure to thapsigargin after ATP or isoproterenol stimulation caused a further increase in [Ca2+]i. However, ATP and isoproterenol were not able to elicit a further increase in [Ca2+]iafter exposure of the cells to thapsigargin. Relatively few cells reacted to isoproterenol stimulation, but nearly all cells reacted to isoproterenol if ATP was added together with, or prior to isoproterenol stimulation. Moreover, the effect of ATP was potentiated by prior or simultaneous addition of isoproterenol. Furthermore, ATP decreased [Ca2+]iin the presence of thapsigargin probably due to agonist‐induced export of intracellular calcium. The results may suggest the existence of three thapsigargin sensitive pools; one opened by ATP acting through P2‐purinergic receptors and IP3, one opened by isoproterenol acting through β2‐adrenergic receptors, and a third pool not sensitive to ATP or isoproterenol.
GANGLIOSIDE‐MEDIATED METABOLIC SYNCHRONIZATION OF PROTEIN SYNTHESIS ACTIVITY IN CULTURED HEPATOCYTES
Authors: Brodsky Vsevolod Y. , Nechaeva Natalia V. , Zvezdina Natalia D. , Novikova Tatjana E. , Gvasava Inna G. , Fateeva Valentina I. , Prokazova Nina V. , Golovanova Natalia K. 
Published: September 2002

AbstractAn ultradian oscillation of protein synthesis was detected by synchronization of metabolic activity in rat hepatocyte cultures. This oscillation occurs in dense cultures in fresh medium, but not in sparse ones. Metabolic synchronization of sparse cultures, however, was initiated by conditioned medium or addition of 0.3–0.5μm of a mixture of bovine brain gangliosides to fresh culture medium along with either 0.06–0.2μm GM1 or 0.1–0.2μm GDIa. GTIb and GDIb did not produce oscillations, nor did human liver ganglioside GM3. High expression of GM1 ganglioside determinants in hepatocytes maintained in the conditioned medium purified polyclonal antibodies to GM1 was coupled with protein synthetic oscillatory activity, i.e. metabolic synchronization. Incubation of dense cultures with GM1‐antibodies for 24h decreased the amplitude of these oscillations. In sparse cultures maintained in fresh medium where protein synthesis showed no oscillatory pattern, GM1 expression was low.
ULTRASTRUCTURE OF CHENOPODIUM RUBRUM L. APICES DURING THE EFFECT OF FUSICOCCIN AND PHOTOPERIODIC INDUCTION
Authors: Lozhnikova V. , Komarova E. , Muromtsev G. 
Published: September 2002

AbstractPlant transition from vegetative to reproductive development is associated with ultrastructural changes in stem apices. Those seen in Chenopodium rubrum L. under the influence of fusicoccin in many ways resemble those induced by a short‐day treatment favourable to flowering. This suggests that fusicoccin can play a definite (physiological) role in plant development.
KINETIC CHARACTERIZATION OF CALCIUM UPTAKE BY THE RAT LIVER GOLGI APPARATUS
Authors: Rojas Patricio , Surroca Amarilys , Orellana Ariel , Wolff Daniel 
Published: September 2002

AbstractWe carried out a kinetic characterization of the Ca2+active transport in the rat liver Golgi Apparatus (GA) membrane. Calcium accumulation by vesicles of a GA enriched fraction was found to be a function of both Ca2+and ATP‐Mg concentrations, it was inhibited by 2μm thapsigargin but not stimulated by 3μm calmodulin. The kinetic parameter values obtained for the GA Ca2+pump were: Jmaxof 3.96nmol/mg min, Kmfor Ca2+of 0.150μm and two Km's for ATP of 1.14μm and 519μm. These results were almost identical to those obtained for the endoplasmic reticulum (ER) fraction, indicating that the GA Ca2+pump is a sarco/endoplasmic reticulum (SERCA) P‐type, analogous—if not identical—to that present in the ER.
APOPTOSIS IS A MODE OF CELL DEATH IN THE POLYKARYON‐FORMING UNIT ASSAY
Authors: Manti Lorenzo , Bowen Ifor D. , Mason Malcolm D. , Court Jon B. 
Published: September 2002

AbstractIn the polykaryon‐forming unit (PFU) assay, which defines cell survival as the ability to form a cytochalasin‐induced polykaryon of predetermined ploidy, the mode of PFU deletion is not known. Incubation of L5178Y‐S PFU in cytochalasin resulted in polyploidy (≥32C) and most polykaryons (>75%) ultimately underwent apoptosis, detected using chromatin condensation and externalised phosphatidylserine. However, large polykaryons carrying terminal deoxynucleotidyl transferase‐mediated dUTP nick end‐labelling (TUNEL)‐labelled DNA strand breaks were not observed, presumably due to rapid loss of DNA. Gamma irradiation of PFU prior to cytochalasin exposure caused a reduction in the frequency of highly polyploid cells (>16C), consistent with either a supra‐induction of apoptosis or a reduction in the ability of PFU to reach high ploidies. We conclude that L5178Y‐S PFU are deleted by apoptosis.
Cu—Zn SUPEROXIDE DISMUTASE INHIBITS LACTATE DEHYDROGENASE RELEASE AND PROTECTS AGAINST CELL DEATH IN MURINE FIBROBLASTS PRETREATED WITH ULTRAVIOLET RADIATION
Authors: Kimura Hirokazu , Minakami Hisanori , Otsuki Kunio , Shoji Akira 
Published: September 2002

AbstractThe effects of adding Cu—Zn superoxide dismutase (Cu—Zn SOD) to culture medium of the murine fibroblast cell line, L‐929, pretreated with UV‐B (312nm, 480mJ/cm2) have been investigated. Cell injury was monitored by the release of lactate dehydrogenase (LDH) into the medium, and cell death by the trypan blue exclusion test. UV‐B radiation induced cell death by apoptosis, as demonstrated by DNA fragmentation. Over the range 0.1–0.3μm Cu—Zn SOD, a significant dose‐dependent protection against cell death was obtained of the UV‐B exposed cells. Cell death correlated with the amount of LDH released into the medium, and Cu—Zn SOD treatment inhibited this. Heat‐denatured Cu—Zn SOD did not affect either cell viability or the release of LDH from the cells. Endogenous Cu—Zn SOD activity, monitored by chemiluminescence, decreased by 20% in UV‐B‐irradiated cells; the addition of 0.3μm exogenous Cu—Zn SOD to the medium did not affect intracellular Cu—Zn SOD activity. These results establish that Cu—Zn SOD added to extracellular medium can protect cells against injury caused by UV‐B exposure.