bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and secretion of an estrus stage‐specific protein by rat uterus.
Authors: Yang L. S. , Marshall A. , Dao B. , Koide S. S. 
Published: October 2002

ABSTRACTA specific protein with an estimated molecular weight of 260 kDa was found to be synthesized and secreted into the incubation medium by rat uterus only during the estrus stage of the cycle. This secreted uterine protein was designated as estrus stage‐specific protein (ESP). ESP was not produced by pregnant, lactating or immature pup rat uteri. Estradiol administered to ovariectomized rats induced production of ESP which was blocked by the antiestrogen, ICI 182, 780. The present results show that the synthesis and secretion of ESP is regulated by estradiol and this protein maybe involved in blastocyst implantation.
Batten disease fibroblasts in culture accumulate mitochondrial ATP synthase subunit 9.
Authors: Tanner Allison , Dice J. Fred 
Published: October 2002

AbstractBatten Disease is a lysosomal storage disease in which the major component that accumulates is subunit 9 of mitochondrial ATP synthase. Whether or not fibroblasts in culture exhibit this phenotype is controversial. We show that fibroblasts from a human Batten Disease patient and from a mouse model of this disease exhibit autofluorescent inclusion bodies. We also demonstrate that levels of ATP synthase subunit 9 are elevated in these diseased fibroblasts when compared to control cells. However, the exact growth state of the human fibroblasts was critical, and this factor probably accounts for discrepencies in the literature.
Digital image analysis of chromatin fibre phenotype after "in situ" digestion with restriction endonucleases
Authors: Gosálvez Jaime , López‐Fernández Carmen , Fernández José L. , Goyanes Vicente J. , Buño Ismael 
Published: October 2002

AbstractRestriction Endonucleases (REs) may recognize, cleave and remove DNA from fixed chromatin producing specific chromosome banding patterns. However, the modifications produced in the chromatin fibre are not easy to evaluate and compare. The aim of the present investigation was to visualize differences resulting in the texture of the chromatin fibre from metaphase chromosomes after each digestion using digital image analysis (DIA) facilities. To this purpose, metaphase chromosomes derived from a L‐929 mouse cell line were digested with different REs (AluI, HpaII and HaeIII).Since light microscopy does not permit the observation of the chromatin fibre, DIA was performed on digitalized images of metaphase chromosomes under electron microscopy. The application of a LUT (Look Up Table) within the DIA software assigns a colour to each grey level of a digital image. The results obtained using a particular LUT, which permits the discrimination of specific chromatin fibre phenotypes resulting from each digestion, are reported and compared with those obtained under the light microscope.
A comparative study of the desquamation of urothelial cells during gestation and in adults mice following moderate stress or endotoxin treatment
Authors: Jezernik K. , Medalia O. , Aronson M. 
Published: October 2002

AbstractThe present paper deals with the comparative EM study of the detachment of mouse urinary bladder epithelial cells under various physiological conditions, namely, during gestation and in adult mice following induction by endotoxin or by exposure to moderate stress. It has been shown that desquamation during gestation involves two distinct modes, shedding of single cells and formation of apoptotic bodies. Moderate stress in adult female mice induced by constant illumination for 72 or 96 hours, results in desquamation of superficial and intermediate cells. Application of LPS is followed by desquamation of single cells and whole sheets of cells.Cell detachment involves interruption of tight junctions between neighbouring cells and formation of numerous cup shaped vesicles, multivesicular bodies and vacuoles at the base of desquamating cells. LPS induces desquamation entails delivery of lysosomal enzymes extracellulary into the intercellular space. In the areas of sloughing the bladder epithelium lack permeability barrier. Desquamated cells in the bladder lumen are mostly alive. These results clearly demonstrate the existence of specific adhesion mechanisms of detachment and desquamation of uroepithelial cells.
Genome size and chromosomes in marine sponges [Suberites domuncula, Geodia cydonium]
Authors: Imsiecke Georg , Custodio Marcio , Borojevic Radovan , Steffen Renate , Moustafa Mohamed A. , Müller Werner E. G. 
Published: October 2002

AbstractThe genome size of the marine sponges Suberites domuncula and Geodia cydonium has been determined by flow cytofluorometric analysis using diamidino‐phenylindole [DAPI]. Using human lymphocytes as reference the amount of DNA in cells from S. domuncula has been determined to be 3.7 pg and that of G. cydonium 3.3 pg. While no chromosomes could be identified in G. cydonium, the karyotype of the Suberites domuncula is 32 chromsomes in the diploid state. The size of the chromosomes was between 0.25 and 1.0 μm. No pronounced banding pattern was visible.
Modulation of human Caco‐2 intestinal epithelial cell phenotype by protein kinase C inhibitors
Authors: Basson Marc D. , Hong Fu 
Published: October 2002

AbstractProtein kinase C (PKC) isoforms are altered in colon tumors and upon exposure of intestinal mucosa to nutrients. We evaluated the effects of the PKC inhibitors staurosporine and calphostin C on human Caco‐2 intestinal epithelial proliferation, motility, and differentiation. Motility was quantitated by monolayer expansion and the brush border enzymes dipeptidyl dipeptidase (DPDD) and alkaline phosphatase (AP) by synthetic substrate digestion. Staurosporine (0.03‐1.0 ng/ml) and calphostin C (10−12M‐10−4 M) dose‐dependently inhibited monolayer expansion and AP but stimulated DPDD. Proliferation was also inhibited but the effects of each inhibitor on motility, AP, and DPDD were preserved after mitomycin C proliferative blockade, suggesting that these effects were proliferation‐independent. PKC inhibitors independently inhibit motility, AP and proliferation in human intestinal Caco‐2 epithelial cells, but selectively stimulate the small intestinal differentiation marker DPDD. PKC may regulate small intestinal epithelial differentiation.
Inducible expression of Mad accelerates growth arrest of serum deprived human glioblastoma cells
Authors: Roy Baishali , Reisman David 
Published: October 2002

ABSTRACTMad is a basic‐helix‐loop‐helix leucine zipper protein that heterodimerizes with Max. Mad: Max heterodimers recognize the same DNA binding sites as Myc: Max heterodimers. However, Myc and Mad are thought to influence transcription and cell proliferation in opposite ways through interaction with Max. While Myc activates transcription and cell proliferation Mad represses these activities (Ayer et. al., Cell 72, 211‐222, 1993). We have constructed an expression vector containing the mad cDNA cloned downstream of an inducible viral promoter. Cell lines carrying the construct were derived by transfection into human glioblastoma cells and the effect of Mad induction on their growth rate was studied. When the cells were cultured in low serum concentrations (0.1%) Mad induction resulted in accelerated growth arrest. These findings are consistent with the proposed growth repression function of the Mad protein.
NGF: not just for neurons.
Authors: Scully Jackie Leach , Otten Uwe 
Published: October 2002

ABSTRACTNerve growth factor (NFF) is the prototypic member of a family of related neurotrophins (Nts). Although originally defined by its actions in the peripheral and central nervous systems, recent data indicate the presence of extensive interactions between NGF and the endocrine and immune systems steroid hormones are able to modulate the neurosomal expression of NGF, while functional NGF receptors have been detected on cells of the immune system, and increased levels of NGF protein are found during the acute phase of diseases with a significant inflammatory component. These wider functions are likely to be of concern in any attempted therapeutic use of NGF.
Production of human immunodeficiency virus by chronically infected cells grown in protein‐free medium.
Authors: Pintér Claudia , Siccardi Antonio G. , Clivio Alberto 
Published: October 2002

AbstractA human T cell line chronically infected with Human Immunodeficiency Virus (HIV) has been adapted to grow in a chemically defined, protein‐free medium. Virus particles are produced at rates comparable to those of serum‐supplemented cultures; virus preparations free of undesirable proteins can be produced in preparative amounts by simple ultrafiltration procedures and cell culture supernatants can be used as such for the preparation of ELISA solid phases. This material has been used very conveniently for studies concerning characterization of antibodies against HlV‐specific proteins, interaction of HIV with complement components and inclusion of human cell‐derived proteins into virions; we propose its use as a powerful tool for the structural as well as functional analysis of the virus particle itself.
A γ‐tubulin that associates specifically with centrioles in HeLa cells and the basal body complex in Chlamydomonas
Authors: Dibbayawan Teresa P. , Harper John D. I. , Elliott Janet E. , Gunning Brian E. S. , Marc Jan 
Published: October 2002

Abstractγ‐Tubulin is a putative component of microtubule initiating material. To further explore its subcellular distribution in plant and animal cells, we have raised a polyclonal antibody, Rb27, directed towards a conserved region (EEFATEGTDRKDVFFY) of the γ‐tubulin molecule. Immunoblotting of cell protein extracts with Rb27 reveals a polypeptide band of Mr 49 kD in HeLa and a 58 kD band in Chlamydomonas. Although these polypeptides are comparable in size to forms of γ‐tubulin detected previously in mammalian and plant protein extracts by other antibodies to γ‐tubulin, by immunofluorescence microscopy Rb27 gives localization patterns not previously seen. It localizes specifically with the centrioles in HeLa cells and with the basal body complex in Chlamydomonas. Other γ‐tubulin antibodies label pericentriolar material. Because of the similarities in the size of the polypeptides recognized by our and other γ‐tubulin antibodies, and a restricted co‐localization with known microtubule‐organizing centres in evolutionarily distant organisms, we propose that Rb27 recognizes a novel conserved γ‐tubulin isotype.
Effect of microtubule‐specific drugs upon spatial organization of extracellular matrix in fibroblastic cultures.
Authors: Domnina L. V. , Ivanova O. Y. , Vasiliev J. M. 
Published: October 2002

AbstractThe aim of this investigation was to study the effects of microtubule‐specific drugs, taxol and colcemid, on the distribution of cell‐associated extracellular matrix in dense cultures of fibroblasts. Immunomorphological examination of human seven‐day cultures revealed a dense network of fibronectin and tenascin matrix filaments preferentially oriented in parallel with the long axes of cell bodies. Depolymerization of the microtubular system by colcemid and its disorganization by taxol led to rapid and drastic changes in the organization of matrix network: fibronectin and tenascin filaments became disordered and, in particular, lost any orientation. These data show that the microtubular system controls the morphological organization, not only of intracellular cytoskeletal systems, but also of extracellular matrix structures.
A NOVEL METHOD FOR PRODUCTION OF MONOCLONAL ANTIBODIES. EVALUATION AND EXPECTATION OF THE RAT LYMPH NODE METHOD IN CELL AND MOLECULAR BIOLOGY
Authors: SADO YOSHIKAZU , OKIGAKI TOHRU 
Published: October 2002

AbstractA newly developed method using rat lymph nodes provided us with substantial amounts of high quality monoclonal antibodies. The method has characteristic features, a single injection of an emulsified antigen via the rat's hind footpads is sufficient for immunization. Enlarged medial iliac lymph nodes can be used for cell fusion to produce hybridomas 2 weeks and later after the antigen injection. The production frequency of target hybridomas is about 10 times higher than that of a conventional spleen method. Our current knowledge about the production of monoclonal antipeptide antibodies and monoclonal nephritogenic autoantibodies by the method is described.
MOLECULAR MECHANISMS IN DEVELOPMENTAL BIOLOGY
Authors: GIUDICE GIOVANNI 
Published: October 2002

AbstractSome general molecular mechanisms underlying development are described. Namely: those involved in the differentiation of the R7 receptor inDrosophilaembryonic retina; those involved in the determination of embryonic axes and in polar cell differentiation, inDrosophila; those involved in the determination of the AB and P cell lineage and in vulva differentiation inCaenorhabditisembryos.
TRANSCRIPTIONAL CONTROL OF CELL CYCLE PROGRESSION: THE HISTONE GENE IS A PARADIGM FOR THE G1/S PHASE AND PROLIFERATION/DIFFERENTIATION TRANSITIONS
Authors: STEIN GARY S. , STEIN JANET L. , van WIJNEN ANDRÉ J. , LIAN JANE B. 
Published: October 2002

AbstractThe histone gene is a paradigm for transcriptional control at the G1/S phase transition point in the cell cycle. The histone gene promoter provides a blueprint for integration of regulatory signals which mediate responsiveness to factors controlling competency for cell cycle progression at the initiation of DNA replication. The downregulation of proliferation at the onset of differentiation is accompanied by and functionally linked to modifications in protein—DNA and protein—protein interactions at histone gene promoter regulatory elements. Chromatin structure, nucleosome organization and gene‐nuclear matrix interactions facilitate crosstalk between regulatory sequences and targeting of transcription factors to cognate binding domains.
X‐RAY MICROANALYSIS IN CELL BIOLOGY AND CELL PATHOLOGY
Authors: ROOMANS GODFRIED M. , VON EULER ANNE 
Published: October 2002

AbstractElectron probe X‐ray microanalysis has been used for the last 25 years by biologists to obtain information about the distribution of elements at the cell and tissue level. During this period, progress has mainly been made through the development of more adequate techniques for specimen preparation (mainly low temperature techniques) and quantitative analysis, so that accurate analysis of the physiologically important cellular ions can be carried out. Use ofin vitrosystems and cell cultures may further increase the number of problems to which X‐ray microanalysis can be applied. Among the numerous applications of X‐ray microanalysis in cell biology and cell pathology, applications in the areas of epithelial ion transport, the role of calcium in secretory and contractile cells, and the role of ions in cell proliferation and cancer are discussed in more detail.
MAINTENANCE OF IONS, PROTEINS AND WATER IN LENS FIBER CELLS BEFORE AND AFTER TREATMENT WITH NON‐IONIC DETERGENTS
Authors: CAMERON IVAN L. , HARDMAN W. , FULLERTON GARY D. , MISETA ATTILA , KOSZEGI TAMAS , LUDANY ANDREA , KELLERMAYER MIKLOS 
Published: October 2002

AbstractIf the plasma membrane and its associated transport proteins are solely responsible for maintenance of the asymmetric solute distribution then disruption of the plasma membrane would quickly lead to the symmetric distribution of all unattached inorganic ions between the cell and the extracellular environment. To test this hypothesis fresh pig lenses were incubated in Hanks ’ balanced salt solution in either absence or presence of non‐ionic detergents (0.2 % Triton X‐100 or 0.2 % Brij 58). Both detergents caused permeabilization of every lens fiber cell as shown by electron microscopy. The flux kinetics of K+, Mg2 +, Na+, Ca2 +, water and protein out of and into the permeabilized lens fiber cells was measured. Triton X‐100 caused a faster flux rate of all solutes than did Brij 58. The Triton X‐100 induced flux of solutes and water was associated with a decrease in lens ATP. Incubation of untreated lenses in solutions of different osmotic pressures at 0 °C demonstrated that the major fraction of lens water was osmotically unresponsive. Thus the asymmetric distribution of solutes in lens fiber cells is dependent on an intact plasma membrane and on a co‐operative ATP‐dependent association between K+, Mg2 +, water and cytomatrix proteins.
CANNABINOID ENANTIOMER ACTION ON THE CYTOARCHITECTURE
Authors: WILSON RONALD G. , TAHIR STEPHEN K. , MECHOULAM RAPHAEL , ZIMMERMAN SELMA , ZIMMERMAN ARTHUR M. 
Published: October 2002

AbstractThe negative and positive enantiomers of 7‐hydroxy‐ Δ6‐tetrahydrocannabinol‐dimethylheptyl (designated HU‐210 and HU‐211 respectively) differentially affect undifferentiated and differentiating cultured pheochromocytoma cells (PC‐12 cells). In general, cell viability and cell proliferation were suppressed to a much greater extent with HU‐210 than with HU‐211 in differentiating cells. The effects of these synthetic cannabinoids on the cytoskeleton of PC‐12 cells were examined by epifluorescence and confocal microscopy. In both undifferentiated and differentiating PC‐12 cells, HU‐211 has little effect on the cytoarchitecture whereas HU‐210 disrupts the distribution of microtubules and microfilaments. Vacuoles (2–4 μm) were evident in the cytoplasm of HU‐210‐treated cells but not in the cytoplasm of HU‐211‐treated cells or in vehicle controls. Tubulin and actin mRNA levels were reduced to 5 and 40 %, respectively (relative to untreated controls) in 10 μmHU‐210‐treated cells whereas the same concentration of HU‐211 reduced tubulin and actin mRNA levels to 90 and 95 %, respectively. A comparison of the effects of the paired enantiomers and Δ1‐THC on the cellular parameters studied reveals that in differentiating cells the action of Δ1‐THC is intermediate between that of HU‐210 and HU‐211. This study demonstrates that compared to HU‐210 and Δ1‐THC the positive enantiomer HU‐211 has little cellular activity.
ONTOGENY OF ANGIOTENSIN II RECEPTORS
Authors: SHANMUGAM SADOUTOUNNISSA , SANDBERG KATHRYN 
Published: October 2002

AbstractAside from the well known role of angiotensin II (Ang II) in blood pressure regulation and fluid homeostasis, accumulating evidence suggests that the octapeptide hormone also plays a role in growth and development. There are two major classes of Ang II receptors (AT1and AT2) which mediate Ang II action. Both classes are members of the large superfamily of seven transmembrane domain spanning receptors. Fetal tissue express high levels of AT receptors. Throughout fetal and postpartum life, the AT1and AT2tissue distribution changes dramatically. The evolution of each receptor type is distinct and varies according to the organ. Thus, the different patterns of temporal expression of each receptor class could be related to various roles that Ang II may play during development.
NOVEL MARKERS FOR CONSTITUTIVE SECRETION USED TO SHOW THAT TISSUE PLASMINOGEN ACTIVATOR IS SORTED TO THE REGULATED PATHWAY IN TRANSFECTED PC12 CELLS
Authors: HARRISON T. M. , CHIDGEY M. A. J. , UFF S. 
Published: October 2002

AbstractThe rat pheochromocytoma cell line PC12 contains two distinct pathways of protein secretion. Proteins secreted via the regulated pathway are stored in secretory vesicles and exocytosed only in response to a specific signal, whereas proteins secreted via the constitutive pathway are exported continuously. Analysis of regulated secretion of a heterologous protein in this system often relies on comparison of secretion rates with those of endogenous proteins known to be secreted via the constitutive route. In order to improve these controls, we have evaluated a number of secreted enzymes, selected for the sensitivity and convenience of their assays, as transgenic markers for the constitutive pathway. We show that both human‐secreted placental alkaline phosphatase (SEAP) and bacterial β‐lactamase operate in this way in transfected PC12 cells. In contrast, transfected human tissue plasminogen activator (tPA) is shown to be sorted to the regulated pathway.
SYNERGISTIC REGULATORY EFFECTS OF TNFα, IL‐1αAND IFNα ON THE GROWTH AND DIFFERENTIATION OF DAUDI LYMPHOMA CELLS
Authors: SANTAVENERE E. , DI PIETRO R. , CENTURIONE M. A. , DI DOMENICANTONIO L. , TRUBIANI O. , RANA R. A. 
Published: October 2002

AbstractThe regulatory effects of the combined treatment of tumour necrosis factorα (TNFα), interleukin‐1α (IL‐1α) and interferonα(IFNα) on the growth and differentiation of Daudi lymphoma cells were investigated. By means of anti‐BrdU monoclonal antibodies and [3H‐thymidine] incorporation a reduced proliferation rate was shown both through a combi‐nation of TNFα with either IL‐1α or IFNα and, above all, through simultaneous treatment with the three cytokines. In parallel, the degree of differentiation was evaluated via morphological criteria and detection of Fc receptors (FcR) and appeared higher after treatment with the three cytokines. Our results provide evidence of the increased sensitivity of this cell line to this combined treatment supporting the existence of a synergistic interaction in inducing the antiproliferative and differentiative effects.
HUMAN SPERM β‐GLUCURONIDASE IS POORLY EXTRACTABLE BY TRITON X‐100
Authors: BRANDELLI ADRIANO , MIRANDA PATRICIA V. , TEZÓN JORGE G. 
Published: October 2002

AbstractA part of sperm glycosidase activities was detected as detergent‐insoluble after sequential extractions with Triton X‐100. Sixty per cent of total β‐glucuronidase activity was found in the detergent‐insoluble fraction. This portion of β‐glucuronidase was resistant to extractions in the presence of 1mKCl, chaotropic agents, colchicine or cytochalasine B, being only partially solubilized by 3mKCl or DNAse I treatment. Results demonstrate that β‐glucuronidase is tightly associated to the Triton X‐100 resistant fraction.
THE CONFORMATION OF CLATHRIN LIGHT‐CHAINS ON TRISKELIONS PROBED BY ANTIBODY INHIBITION
Authors: JACKSON A. P. 
Published: October 2002

AbstractThe conformation of clathrin light‐chains along the proximal arm of the clathrin triskelion was studied by using rabbit anti‐(light‐chain peptides) to inhibit the binding of a mouse monoclonal antibody against an epitope in the amino‐terminal region. Prior incubation of triskelions with rabbit antisera raised against the extreme carboxyl‐terminal of the light‐chains partially inhibited binding. The inhibition was largely removed when tested on light‐chains that had been freed from triskelions. This suggests that when the light‐chains bind the heavy‐chain, they adopt a conformation in which the amino and carboxyl‐terminal domains are not fully extended, but fold such that these two domains face each other.
NUCLEOLAR ORGANIZATION AS REVEALED IN CELL SPREADS
Authors: GHOSH SIBDAS , PAWELETZ NEIDHARD 
Published: October 2002

AbstractThe nucleolar organization has been studied in spreads of cells either untreated or treated with hypotonic salt solution for different periods. A network corresponding to the nucleolonema becomes evident with progressive hypotonic treatment. The network reveals units comparable to the rDNA transcriptional units in length and is associated with tufts of fibrils and granules. Spread preparations from cycloheximide treated cells reveal a thread‐like axis and often ‘Christmas tree’‐like configurations within these units. Spacers joining the units can also be detected. It is supposed that the transcriptional units move outwards with their transcriptional products where the processing takes place. In loose nucleoli, this network forms the nucleolonema, which remains associated with the granules, the processed transcriptional products. In compact nucleoli the network is obliterated by the granules and they form the major component of the nucleoli. Such organization represents all the events in the transcription and processing of ribosomal RNA.