Can J Ophthalmol, 1992 Dec, 27(7), 331 - 5 Cell culture of macular epiretinal membranes; MacDonald IM et al.; To attempt to differentiate the cells of origin in epiretinal membranes, cells were cultured from an idiopathic epiretinal membrane and an epiretinal membrane that formed after successful repair of a retinal detachment . The cells exhibited a variety of forms . When the cells from the idiopathic epiretinal membrane were incubated with melanin from donor eyes a population of small cells accumulated the pigment, but the large, flat cells did not . The epiretinal membrane was not composed of a single cell type . Although a population of cells exists within epiretinal membranes, no one cell type could be identified as the cell type of origin. Eur J Cell Biol, 1992 Dec, 59(2), 405 - 13 Microneme secretion in Coccidia: confocal laser scanning and electron microscope study of Sarcocystis muris in cell culture; Entzeroth R et al.; A monoclonal antibody (mcab) raised against a subcellular fraction of Sarcocystis muris cystozoites was used to localize microneme antigens before, during and after invasion of cultured cells . The mcab recognized a 20 and 22 kDa protein under reducing and non-reducing conditions on Western blots and localized an antigen in cystozoites in the apical part of the parasites . Confocal laser scanning microscopy of invading cystozoites revealed the secretion of a microneme antigen at the apical tip of the parasite . The secreted microneme antigen was attached to the host cell surface at the invasion site and spread along the surface of the infected cells . Electron microscopy using immunogold labeling showed that the microneme antigen was distributed in patches on the surface of infected cells and present on infected cells more than 60 min post-infection . The function of microneme antigens during parasite-host cell interactions is discussed. Neuroreport, 1992 Dec, 3(12), 1077 - 80 bFGF induces its own gene expression in astrocytic and hippocampal cell cultures; Flott-Rahmel B et al.; Basic FGF mRNA induction by bFGF was investigated in cell cultures from rat brain, i.e . postnatal day 2 cortex and embryonic day 18 hippocampus . In situ hybridization shows that after bFGF treatment (10(-10) M) for 14 h neurones and glial cells show a remarkable increase in bFGF mRNA production . Incubation of astrocytes with antisense bFGF phosphorothioate oligodeoxynucleotides (bFGF-PTOs) resulted in an inhibition of both bFGF induced and serum induced proliferation . The results indicate that bFGF is capable of inducing its own mRNA production . This induction, i.e . new synthesis of bFGF mRNA, seems to be essential for the mitogenic effect of both bFGF and serum components. Toxicon, 1992 Dec, 30(12), 1545 - 54 An assessment of potential chemoprotectant activity against ricin toxicity by mechanism based glycosidase inhibitors in macrophage J744A.1 cell cultures; Hassoun EA et al.; The abilities of potential chemoprotectants to inhibit cytotoxicity of ricin have been determined in vitro, using the macrophage cell line J744A.1 . Six compounds were tested: alpha- and beta-galactopyranosylamine; N-bromoacetyl-alpha-D-galactopyranosylamine; N-bromoacetyl-beta-D-galactopyranosylamine; N-bromoacetylglucopyranosylamine; and N-bromoacetylmannopyranosylamine . Of the six compounds which were tested, only N-bromoacetyl-alpha-D-galactopyranosylamine and N-bromoacetyl-beta-D-galactopyranosylamine exhibited significant activity against ricin toxicity, as indicated by the release of lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) . The alpha-isomer provided greater protection against ricin toxicity and also exhibited less inherent cytotoxicity in the absence of ricin, as compared to the beta-isomer . Neither the alpha- and beta-galactopyranosylamines nor the glucose and mannose analogs were promising as potential chemoprotectants. J Neurosci Res, 1992 Dec, 33(4), 579 - 89 In search of the central respiratory neurons: I . Dissociated cell cultures of respiratory areas from the upper medulla; Fitzgerald SC et al.; Dissociated cells from the areas of the nucleus ambiguus and the nucleus tractus solitarius obtained by tissue punch or block dissection from coronal slices of the medulla at the level of the obex were cultured from fetal rats at 18 to 21 days gestation . The dissociated neurons were plated either directly in vitrogen-coated 35 mm tissue culture dishes or in such dishes which had been seeded with subcultures of cortex- or medulla-derived astrocytes . After the astrocytes reached confluency and were treated with an antimitotic agent, dissociated nucleus ambiguus or nucleus tractus solitarius was plated at 0.5-1.0 x 10(6) cells per dish . Neurons grew well on monolayers of medullary or cortical astrocytes, but survived poorly on vitrogen-coated dishes without a cellular substrate . Rat medulla was preferred as the source of astrocytes . Tissue dissociation with papain rather than trypsin produced less cellular debris, and the neuronal yield from the tissue was higher . The neuronal population was heterogenous in morphology including small and large bipolar, pyramidal, and multipolar cells . Neurons sensitive to CO2 and/or low pH (Rigatto et al., J Neurosci Res 33:590-597, 1992) did not appear to have any definitive morphologic characteristics, but most were multipolar . These neurons stained well with antibodies to neuron-specific enolase and Fragment C of tetanus toxin, but not to choline acetyltransferase (ChAT) . These findings suggest that neurons possibly responsible for the central regulation of respiration can be maintained for several weeks in dissociated cell culture, providing a system for neurotransmitter, electrophysiological, and morphological studies. Scand J Gastroenterol, 1992 Dec, 27(12), 1077 - 83 The effect of somatostatin analogue SMS 201-995 on serotonin levels in the medium of primary carcinoid cell cultures; Jacobsen MB et al.; Carcinoid cell cultures were established from primary tumours and liver and mesenteric metastases . The cells continued to produce serotonin for up to 6 months . Cells from different tumours showed different properties . In most wells carcinoid cells grew on a layer of fibroblasts . The tendency to co-culture seemed to be less marked in cells from liver biopsy specimens . The amount of serotonin decreased to 63% 300 min after addition of the somatostatin analogue SMS 201-995 (SMS) to the culture, compared with controls (p < 0.05; n = 10) . This decrease was observed up until 12 days, when SMS was added at each change of medium (p < 0.005; n = 8) . In the first 10 min, however, SMS induced an increase in serotonin concentration (p < 0.005; n = 11) . This effect may be related to other, immediate stimulatory effects of SMS seen in other cell lines originating from neural ridge-derived tissue . We believe it is important to elucidate the properties of individual tumours, as choice of therapy may vary between patients with the same diagnosis . We have described a method to obtain such information within a couple of days, before a definite treatment is selected. Hum Pathol, 1992 Dec, 23(12), 1332 - 9 Contribution of immunohistochemistry, electron microscopy, and cell culture to the characterization of nonfunctioning pituitary adenomas: a study of 40 cases; Croue A et al.; We studied 40 endocrinologically inactive pituitary adenomas by immunohistochemistry, electron microscopy, and cell culture in order to determine the incidence of gonadotropic adenomas and to classify nonfunctioning adenomas . Immunohistochemical studies using a large panel of monoclonal and polyclonal antibodies identified the following nonfunctioning adenomas: 20 gonadotropic adenomas, four silent corticotropic adenomas, one plurihormonal adenoma, and 15 nonsecreting adenomas . Among nonsecreting adenomas, ultrastructural study of 13 cases identified seven null cell adenomas and six oncocytomas . Silent corticotropic adenomas were classified into subtypes I, II, and III according to Kovacs and Horvath . Most often, gonadotropic adenomas displayed a varying number of oncocytic cells, characteristic secretory granules, and a prominent Golgi apparatus . Postembedding immunoelectron microscopy was performed on eight gonadotropic or nonsecreting adenomas, but this technique did not provide any additional information . Six gonadotropic adenomas and 10 so-called nonsecreting adenomas were studied in primary cell cultures . The six gonadotropic adenomas and seven of the 10 nonsecreting adenomas released gonadotropins in the culture medium . The use of in vitro results as a supplementary diagnostic criterion allowed classification of the 40 nonfunctioning adenomas as follows: 27 gonadotropic adenomas, four silent corticotropic adenomas, one plurihormonal adenoma, and eight nonsecreting adenomas . These results demonstrate a high proportion of gonadotropic adenomas among nonfunctioning adenomas (67.5%) and the usefulness of several techniques in characterizing this type of pituitary adenoma. Parasitology, 1992 Dec, 105 ( Pt 3), 417 - 23 Theileria annulata-infected cells produce abundant proteases whose activity is reduced by long-term cell culture; Baylis HA et al.; Lysates of Theileria annulata-infected bovine lymphoblastoid cells and their uninfected counterparts were tested for protease activity using gelatin substrate SDS-PAGE . The infected cells produced a number of extra activities at pH 8.0 in the presence of Ca2+ . Calcium was found to enhance the activities but was not an absolute requirement . Studies using inhibitors, including E64, 3,4-dichloroisocoumarin, pepstatin and 1, 10-phenanthroline suggested that the activities were metalloproteases . We analysed two vaccine lines; the Ode line from India and the Ankara Pendik line from Turkey . In the Ode line the later passage had very much reduced levels of the enzyme activities . In the case of the Ankara Pendik line both stages analysed had very low protease activities, but a reduction from the early to late passage was also observed . The reduction in the level of protease activity was also observed as a gradual process during on-going culture of lines derived from the Hissar and Ode stocks . In the Ode line we demonstrated a parallel decrease in the production of microschizonts upon temperature shift in vitro. Neurochem Res, 1992 Dec, 17(12), 1163 - 80 Neuronal cell cultures: a tool for investigations in developmental neurobiology; Cestelli A et al.; The aim of this review is to describe environmental requirements for survival of neuronal cells in culture, and secondly to survey the complex interplay between hormones, neurotrophic factors, transport- and extracellular matrix- proteins, which characterize the developmental program of differentiating neurons . An overall reconsideration of the literature in this vast field is above the limits of the present paper; since progress and refinement in the techniques of neuronal cell cultures have paralleled the advancement in Developmental Neurobiology, we will run instead through the main steps which form the conceptual framework of neuronal cell cultures. Fertil Steril, 1992 Dec, 58(6), 1220 - 9 Proliferative and morphogenic changes induced by the coculture of rat uterine and peritoneal cells: a cell culture model for endometriosis; Sharpe KL et al.; OBJECTIVE: To evaluate the proliferative and morphogenic effects induced by the coculture of uterine and peritoneal cells to establish a cell culture model for endometriosis . DESIGN: Uterine epithelial and stromal cells and peritoneal mesothelial and subserosal cells were cocultured with homologous cell types, heterologous cell types, or as isolated populations using a bicameral chamber design . SETTING: Department of Obstetrics and Gynecology at the University of Missouri, Columbia, Missouri . ANIMALS: Cells isolated and purified from five mature female Sprague Dawley rats of normal reproductive status were used to establish cell cultures . MAIN OUTCOME MEASURES: Cell proliferation (deoxyribonucleic acid synthesis) was measured by the incorporation of 3H-thymidine, and cell morphology was assessed using inverted phase-contrast microscopy . RESULTS: Peritoneal mesothelial cells augmented proliferation and induced cellular aggregation of uterine stromal cell monolayers . Peritoneal subserosal cells amplified proliferation and induced an irregular, compacted morphology in uterine epithelial cells . The proliferation and morphology of the two peritoneal cell types was not altered by uterine cell coculture . CONCLUSIONS: The coculture of uterine and peritoneal cells in bicameral chambers provides a tool to study the paracrine interactions of cells that comprise the endometriotic lesion . The altered proliferation and morphology of the uterine cells may be related to the histologic and biochemical asynchrony observed between uterine endometrium and ectopic endometriotic tissue in vivo and offers insight into possible mechanisms of the histogenesis of endometriosis. J Clin Microbiol, 1992 Dec, 30(12), 3181 - 4 Detection of Toxoplasma gondii parasitemia by gene amplification, cell culture, and mouse inoculation; Hitt JA et al.; Diagnosis of Toxoplasma gondii infection is difficult, especially in immunosuppressed people . The AIDS epidemic has increased the number of people at risk and increased the need for better diagnostic methods . We have compared three methods for detection of T . gondii parasitemia . Rabbits were infected subcutaneously with 10(4) T . gondii tachyzoites . Blood samples were obtained, and buffy coat or leukocyte fractions were prepared . We sought the T . gondii B1 gene by gene amplification by the polymerase chain reaction, and we sought viable T . gondii cells by inoculating fibroblast cell cultures and by mouse inoculation . Thirty-two blood samples were obtained from seven infected rabbits, and 18 were obtained from four control, uninfected rabbits . Parasitemia was detected in 20 of 32 samples (62%) from infected samples by mouse inoculation, 12 of 32 samples (37%) by gene amplification and detection, and 8 of 32 samples (25%) by cell culture . Mouse inoculation requires use of live animals and has a long turnaround time . Currently, cell culture is the least sensitive but most practical and widely available method for the detection of T . gondii parasitemia . Gene amplification and detection was more sensitive than cell culture and may become available in clinical laboratories as techniques are developed further and automated. Calcif Tissue Int, 1992 Dec, 51(6), 443 - 8 FT-IR microscopic mappings of early mineralization in chick limb bud mesenchymal cell cultures; Boskey AL et al.; Chick limb bud mesenchymal cells differentiate into chondrocytes and form a cartilaginous matrix in culture . In this study, the mineral formed in different areas within cultures supplemented with 4 mM inorganic phosphate, or 2.5, 5.0, and 10 mM beta-glycerophosphate (beta GP), was characterized by Fourier-transform infrared (FT-IR) microscopy . The relative mineral-to-matrix ratios, and distribution of crystal sizes at specific locations throughout the matrix were measured from day 14 to day 30 . The only mineral phase detected was a poorly crystalline apatite . Cultures receiving 4 mM inorganic phosphate had smaller crystals which were less randomly distributed around the cartilage nodules than those in the beta GP-treated cultures . beta GP-induced mineral consisted of larger, more perfect apatite crystals . In cultures receiving 5 or 10 mM beta GP, the relative mineral-to-matrix ratios (calculated from the integrated intensities of the phosphate and amide I bands, respectively) were higher than in the cultures with 4 mM inorganic phosphate or in the in vivo calcified chick cartilage. J Immunol, 1992 Dec 1, 149(11), 3524 - 34 Cytokine pattern of Langerhans cells isolated from murine epidermal cell cultures; Schreiber S et al.; In the present study we demonstrate that supernatants of highly enriched cultured Langerhans cells (cLC) display IL-1, IL-6, granulocyte/macrophage (GM)-CSF, and TNF-alpha, but no IL-2, IL-3, IL-4, and IFN-gamma activities . We further show that IL-6, GM-CSF, and TNF-alpha bioactivities can be specifically blocked in the presence of the respective neutralizing mAb . Concerning the IL-1 bioactivity, the combined use of anti-IL-1 alpha and anti-IL-1 beta mAb was needed to completely inhibit the proliferative response of the indicator cell line D10 . One of the difficulties in studying the secretory potential of LC is that even highly enriched cLC are contaminated with keratinocytes (KC), which are known to be a rich source of cytokines . To overcome this problem we compared cytokine bioactivities in supernatants of cell cultures consisting of selected cLC:cKC ratios . These cell mixing experiments revealed that cLC are the major source of the IL-6 bioactivity, whereas IL-1, GM-CSF, and TNF-alpha are predominantly generated by cKC . In order to determine whether the cytokine bioactivities measured in supernatants of epidermal cell cultures are simply caused by an increased release or by de novo synthesis, we performed molecular biologic studies . Polymerase chain reaction analysis of cLC and cKC revealed that IL-1 beta and IL-6 transcripts are virtually limited to cLC, whereas IL-1 alpha, GM-CSF, and TNF-alpha messages are preferentially exhibited by cKC . mRNA coding for IL-2, IL-3, IL-4, and IFN-gamma could neither be amplified from cLC nor from cKC . Furthermore, the quantitative comparison of cytokine transcripts in cLC vs cKC using Northern blot analysis and mRNA detection on the single cell level using in situ hybridization confirmed that cLC generate IL-6, whereas cKC synthesize IL-1 alpha and GM-CSF . Taken together our results demonstrate that cultured murine LC synthesize and secrete IL-1 beta and IL-6, cytokines known to be important accessory molecules in T cell activation. Biotechnology (N Y), 1992 Dec, 10(12), 1572 - 5 Cell culture of Taxus as a source of the antineoplastic drug taxol and related taxanes; Fett-Neto AG et al.; Callus cultures of Taxus cuspidata and Taxus canadensis were induced using different tissue explants including green and red arils, seed contents, young stems and needles . Callus derived from stem segments displayed the best growth in defined media . The culture medium was supplemented with reducing agents and phenolic-binding compounds to inhibit callus darkening and subsequent growth reduction . T . cuspidata explant growth was affected by different concentrations and ratios of 2,4-D and kinetin . Callus tissues of T . cuspidata were extracted for taxol after 2 months in culture and analysed by HPLC . The presence of taxol (0.020 +/- 0.005% of the extracted dry weight) was indicated based on retention time, U.V . spectra, peak purity as assessed by photo-diode array spectroscopy and compared with an authentic taxol standard, as well as by 1H-NMR analysis . Suspension cultures of T . cuspidata were established from the callus cultures, subsequently immobilized onto glass fiber mats, and maintained as immobilized cultures for 6 months . The immobilized cell cultures also produced taxol at levels up to 0.012 +/- 0.007% of the extracted dry weight. Kitasato Arch Exp Med, 1992 Dec, 65(4), 181 - 6 A new neutralization method for influenza virus in cell culture; Taguchi F et al.; A novel neutralization method (ELISA-NT) has been developed for simple detection of neutralizing antibodies to influenza virus in which type specific soluble (S) CF antigen produced by unneutralized virus was measured by anti-S immune (probe) serum and enzyme-labelled Clq . Neutralizing antibody activity was determined within 48 h and expressed as a new term, NT% of the quantity of neutralized virus . A good correlation was found between NT% determined by the ELISA-NT method and NT titer by the conventional method in 82 human serum samples (r = 0.941 for type A and r = 0.875 for type B of influenza virus, p < 0.01). Hum Cell, 1992 Dec, 5(4), 313 - 33 Historical progress and the future of human cell culture research; Moore GE et al.; Progress in human cell culture research is discussed based primarily on our hematopoietic cell culture studies . The article includes a historical background of Burkitt lymphoma cell lines, discovery of EBV, normal B-lymphoblastoid cell lines with EBV, a variety of leukemia, lymphoma, and myeloma cell lines, clinical and theoretical contributions made by studies of T-cell leukemia cell lines, the discovery and clinical relevance of HTLV, HIV and HBLV, early attempts at adoptive immunotherapy of patients with cancer, and the future of human cell culture research . Despite the fact that current cell culture methods permit maintenance of only limited cell types of both normal and malignant origins, biotechnological advances such as hybridoma and recombinant DNA technologies should continue to provide unlimited research opportunities in all fields. Microb Pathog, 1992 Dec, 13(6), 493 - 505 Mouse hepatitis virus A59 increases steady-state levels of MHC mRNAs in primary glial cell cultures and in the murine central nervous system; Gombold JL et al.; Infection of mixed glial cell cultures with mouse hepatitis virus (MHV)-A59 results in an approximately six-fold increase in the level of major histocompatibility complex (MHC) class I mRNA . In situ hybridization of glial cell cultures infected with MHV-A59 again showed enhanced MHC mRNA expression, both in infected and uninfected cells . These results extend our earlier finding that MHC surface antigens are enhanced on astrocytes and oligodendrocytes after MHV-A59 infection and suggest that this enhancement is a result of an increase in the steady-state level of MHC mRNA . We further demonstrate that increases in MHC mRNA occur in the murine central nervous system (CNS) following infection in vivo . Northern blot analysis of RNA from the brains of infected animals showed transient expression of both MHC class I and class II mRNA over the first 14 days of infection . Expression coincided with viral replication and clearance . In situ hybridization of brain sections from infected animals showed that class I and class II expression was widespread throughout all portions of the brain and in uninfected as well as infected cells . Viral RNA, in contrast, was observed in small foci of cells and mostly within the limbic system . Thus enhancement of MHC mRNA was not restricted either to areas of infection or inflammation . The spatial relationship between viral and MHC expression supports our hypothesis that a soluble mediator is involved in the mechanism of the increase in MHC levels . The fact that MHC induction occurs in vivo as well as in vitro suggests MHC may be important in the mechanism of MHV-induced disease. J Nat Prod, 1992 Dec, 55(12), 1732 - 40 Synergistic effect of flavones and flavonols against herpes simplex virus type 1 in cell culture . Comparison with the antiviral activity of propolis; Amoros M et al.; The in vitro activity against herpes simplex virus type 1 of the major flavonoids identified in propolis was investigated . Flavonols were found to be more active than flavones, the order of importance being galangin, kaempferol, and quercetin . The efficacy against HSV-1 of binary flavone-flavonol combinations has been also investigated . The synergy demonstrated by all combinations could explain why propolis is more active than its individual compounds. Prostaglandins Leukot Essent Fatty Acids, 1992 Dec, 47(4), 321 - 5 Endothelin-1 stimulates phospholipid hydrolysis and prostaglandin F2 alpha production in primary human decidua cell cultures; Schrey MP et al.; The regulation of prostaglandin (PG) production by the uterine decidua may be an important mechanism controlling the onset and maintenance of human parturition . The present in vitro study has evaluated the potential for endothelin-1 (ET-1) to activate cell signalling and PGE2 alpha production in human primary decidua cell cultures . ET-1 stimulated a dose-dependent increase in inositol phospholipid hydrolysis and PG precursor release as evidenced by respective increases in {3H} inositol monophosphate accumulation and {14C} arachidonate release from radiolabelled decidua cells . PGF2 alpha production was increased in some but not all cell preparations in response to ET-1 alone . Pretreatment of decidua cells with interleukin-1 beta (IL-1 beta) enhanced PGF2 alpha production but not arachidonate release in response to ET-1 . These in vitro observations support a possible role for ET-1 in the regulation of decidual PG production during parturition. Southeast Asian J Trop Med Public Health, 1992 Dec, 23(4), 726 - 9 IgM capture ELISA for detection of IgM antibodies to dengue virus: comparison of 2 formats using hemagglutinins and cell culture derived antigens; Cardosa MJ et al.; The highly sensitive AFRIMS format IgM capture ELISA for the diagnosis of dengue virus infections requires the use of mouse brain derived hemagglutinins and consequently also the use of 20% acetone extracted normal human serum to eliminate high background . These reagents are not always easily available and we have thus compared the AFRIMS format with another published format which uses cell culture derived antigens (culture fluid, CF, format) in order to determine if it is reasonable to use cell culture derived antigens in situations where hemagglutinins and normal human serum are difficult to obtain . The study shows that using AFRIMS results as the reference point, the CF format described here has a sensitivity of 90% and a specificity of 96%. Matrix, 1992 Dec, 12(6), 439 - 47 Verapamil decreases cyclic load-induced calcium incorporation in ROS 17/2.8 osteosarcoma cell cultures; Vadiakas GP et al.; Bone is a tissue that responds to mechanical load by changing its internal architecture . However, the mode of transmission of mechanical stimuli into biological signals and the effect of load at the cellular level are still not clear . An in vitro system, a Flexercell Strain Unit, was used to apply cyclic load to osteoblast-like cells in culture . In the first series of experiments, ROS 17/2.8 rat osteosarcoma cells, cultured on Flex I, flexible bottomed culture plates, were subjected to a 0.05 Hz, 0.24 STRAIN cyclic load regime for 3 and 7 days, in vitro . One group subjected to load received verapamil, a calcium channel blocker, throughout the experimental period . A second group was exposed to load but received no verapamil . A third group had no drug or load and a fourth group had no load but received verapamil . Cultures were incubated for 24 hours prior to collection with 10 microCi of 45CaCl in the medium, then well bottoms were divided to yield outer (maximum) and inner (minimum) load zones for assay of radioactivity . The effect of verapamil during a 7-day loading period was studied by adding the drug to individual cultures at daily intervals . Results indicated that mechanical loading stimulates calcium incorporation in ROS 17/2.8 cell cultures by day 7 but not by day 3 . Only early verapamil addition decreased load-induced calcium incorporation when drug was added prior to day 4 . If verapamil was added after 4 days, the channel blocker did not diminish load-induced calcium incorporation. FEBS Lett, 1992 Nov 30, 313(3), 295 - 9 Internucleosomal chromatin degradation in myeloma and B-hybridoma cell cultures; Sokolova IA et al.; The activity of Ca/Mg-dependent endonuclease (CME) is strongly inhibited in myeloma X-63.Ag8.653 and B-hybridoma MLC-1c as compared with mouse splenocytes . Nevertheless, pronounced internucleosomal chromatin degradation occurs in both cell lines during long-term cultivation without passing . In isolated cell nuclei of X-63 the activation of CME, which precedes chromatin fragmentation in vivo and loss of cell viability, is revealed . The time-course of CME activation is opposite to cell proliferation and is not accompanied by alterations in enzyme quantity . The results suggest that cell death of X-63 and MLC-1c occurs via apoptosis, and involves the mechanisms controlling the activation and/or interaction of CME with chromatin. Arch Biochem Biophys, 1992 Nov 15, 299(1), 1 - 7 Purification and characterization of dihydrobenzophenanthridine oxidase from elicited Sanguinaria canadensis cell cultures; Arakawa H et al.; Upon treatment of Papaveracea cells with fungal elicitors, the biosynthesis of benzo{c}phenanthridine alkaloids is induced . Dihydrobenzophenanthridine oxidase, which catalyzes a later step in the biogenesis of these alkaloids, is one of the enzymes whose activity is elevated in the process . Here we report the 211-fold purification of the oxidase from elicited Sanguinaria canadensis by a combination of ammonium sulfate fractionation, DEAE-Sephadex, CM-Sephadex, Sephadex G-200, and either phenyl Superose or gel filtration chromatography . The purified enzyme utilized molecular oxygen to oxidize dihydrosanguinarine to sanguinarine with concomitant formation of hydrogen peroxide . A pH optimum of 7.0, Vmax of 27 nkat/mg protein, and apparent Km of 6.0 microM for dihydrosanguinarine were determined . Dihydrochelerythrine was also found to be a substrate for the purified enzyme, displaying an apparent Km of 10 microM . However, neither dihydronorsanguinarine nor the indole alkaloid ajmalicine was oxidized, indicating that the enzyme has some substrate specificity . Apparent molecular weight estimates by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the most purified enzyme preparation obtained contained a major component of 77 kDa and two minor components between 59 and 67 kDa that can be associated with oxidase activity . Purified enzyme preparations possessed activity that was inhibited by sodium diethyldithiocarbamate, sodium azide, potassium cyanide, 1,4-DL-dithiothreitol, and mercaptoethanol. J Med Chem, 1992 Nov 13, 35(23), 4479 - 85 Diamine ligand release from the cisplatin analogue {meso-1,2-bis(2,6-dichloro-4- hydroxyphenyl)ethylenediamine}dichloroplatinum(II) in cell culture medium; Bednarski PJ et al.; The stability of the five-membered chelate ring of the cisplatin analogue {meso-1,2-bis(2,6-dichloro-4- hydroxyphenyl)ethylenediamine}dichloroplatinum(II) was investigated under typical cell culture conditions (IMEM-Richter's medium with 10% fetal calf serum, 37 degrees C) . For this purpose, the platinum compound was radiolabeled with tritium in the meta position of the aromatic ring by an acid-catalyzed tritium-exchange reaction, and a reversed-phase HPLC assay with radiochemical detection was developed to monitor for the presence of the free diamine ligand in the cell culture medium . A gradual increase in radioactivity attributed to the free diamine was found in medium containing the dichloroplatinum(II) complex (ca . 25% after 24 h), indicating that the diamine ligand was being released from the metal atom . When 1 mM glutathione (GSH) was included in the incubation medium, the amount of free diamine nearly doubled after 24 h, while the amount of radioactivity attributed to serum protein-platinum adducts decreased relative to incubations without GSH . On the other hand, the omission of serum from the incubations resulted in a dramatic decrease in the amount of radioactivity eluting under the diamine peak, while the concentrations of the two methionine-Pt adducts, which formed in a 1:1 ratio, rose . Through the use of liquid secondary ion mass spectroscopy, the two methionine-Pt adducts were identified as monomethionine metabolites of the title compound, whereby the two chloride ligands have been replaced by the amino acid . These compounds are probably diastereomers since the sulfur of methionine can coordinate to platinum with equal probability either cis or trans to the R-configured benzylamine carbon . On the basis of the chemical shifts of the MeS groups in the 250-MHz 1H NMR, it is concluded that a S,N-five-membered chelate ring is present in these methionine-Pt adducts. Ukr Biokhim Zh, 1992 Nov-Dec, 64(6), 84 - 7 {A comparative analysis of the proteins from a cell culture and from field plants of the ecdysteroid producer Serratula coronata L.}; Saad ML et al.; Differences in the composition and amount of proteins synthesized in the cell culture and leaves of field plants Serratula coronata have been shown . They proceed from differences in intensity of synthesis of secondary metabolites, ecdysteroids, whose content in the cell culture is considerably lower. Matrix, 1992 Nov, 12(5), 381 - 7 Isolation of hydroxylysyl pyridinoline, a mature collagen crosslink from neonatal rat aorta smooth muscle cell cultures; Stone PJ et al.; Hydroxylysyl pyridinoline (HP) is a nonreducible collagen crosslink derived from three posttranslationally modified lysyl residues . Neonatal rat aorta smooth muscle cell cultures (NNRSMC) produce mg amounts of insoluble collagen . The purpose of the present study was to evaluate the capability of NNRSMC to produce collagen containing HP crosslinks . Cultures were pulsed with {14C}-lysine and then chased for five weeks . Insoluble collagen was prepared by digestion of the cell layer material with porcine pancreatic elastase and trypsin . After acid hydrolysis and cation-exchange chromatography, purified HP was isolated by reversed phase ion-paired chromatography . The material eluting from the HPLC was monitored continuously at 295 nm and the ultraviolet absorption spectrum was recorded every 21 msec . The ultraviolet spectrum of the HP peak was virtually identical to that of standard HP run on the HPLC . The HP exhibited a homogeneity of 97.3% when the ultraviolet spectrum of the apex of the peak was compared with the spectra of the shoulders of the peak . The radioactive HP also exhibited the expected fluorescence emission spectrum . We calculate a mean of 0.40 +/- 0.03 nmol HP/nmol collagen in the three experiments as compared with reported values of 0.57 +/- 0.1 for rabbit aorta . This is the first report of cell culture biosynthesis of chemically measurable amounts of HP . Using such pulse-chase techniques one can study the maturation of intermediate collagen crosslinks into HP . HP can also be used as a marker to study the metabolism of mature collagen molecules during normal and pathologic states. Matrix, 1992 Nov, 12(5), 352 - 61 Type IV collagen synthesis and accumulation in neonatal rat aortic smooth muscle cell cultures; Hospelhorn AC et al.; The production of type IV collagen by cultured neonatal rat aortic smooth muscle cells was monitored over a three-week period to further characterize the extracellular matrix of this unique culture system . Type IV collagen was quantified using a dot immunobinding assay and was found to represent 1% or less of the total collagen produced by these cells in culture . Total collagen represented up to 33% of the total protein . The pattern of type IV collagen production in the media and the cell layer suggests that although these cells synthesize and secrete type IV collagen from the onset of culture, type IV collagen deposition only occurs after the cells have reached confluence . In the presence of ascorbate the amount of type IV collagen peaked in the media in preconfluent cultures . In the absence of ascorbate, little type IV collagen was detected in the media . On the other hand, the presence or absence of ascorbate made little difference in the amount of the total collagen detected in the media, although hydroxylation was affected . Remarkably, in the absence of ascorbate type IV collagen accumulation in the cell layer was similar by the end of the culture period to that in cultures treated with ascorbate . Laminin was not affected by the presence or absence of ascorbate . When these cells were exposed to ascorbate for 24 hours, a peak of soluble elastin was detected in the media . However, soluble elastin was not detected in the media in the absence of ascorbate or in cultures which were maintained in the presence of ascorbate . Modulation of the extracellular matrix with ascorbic acid indicated that type IV collagen deposition did not depend on the presence of ascorbic acid and that there was no discernable interaction between type IV collagen, laminin, and elastin. J Pharmacol Exp Ther, 1992 Nov, 263(2), 703 - 7 Propylbenzilylcholine mustard has greater specificity for muscarinic m2 receptors than for m3 receptors present in cerebellar granule cell culture from rat; McLeskey SW et al.; Both muscarinic m2 receptors that inhibit adenylyl cyclase and m3 receptors that stimulate the hydrolysis of inositol phospholipids are expressed in cerebellar granule cells . In order to determine whether a reserve population of either of these receptors is present in this cell culture, the irreversible muscarinic receptor antagonist, propylbenzilylcholine mustard (PBCM), was used at different concentrations to bind various proportions of available muscarinic receptors . After pretreating the cell cultures with low concentrations of PBCM (< 1 nM), the muscarinic m2 receptor-mediated response decreased . Higher concentrations of PBCM (1-3 nM) were needed to reduce the muscarinic m3 receptor-mediated response . These results suggested that either a reserve population of muscarinic m3 receptors is present or that PBCM shows greater specificity for muscarinic m2 receptors . Because the muscarinic m2 receptor is a 66 kDa protein, whereas the muscarinic m3 receptor is a 92 kDa protein, these receptors can be separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis after being labeled with {3H}PBCM . PBCM appears to specifically bind the 66 kDa m2 receptor at concentrations lower than those required to bind to the 92 kDa m3 receptor . A linear correlation was found between the increased binding of {3H}PBCM to each receptor and the proportional loss of that receptor-mediated response . Thus, a reserve population of either muscarinic m2 or m3 receptors does not appear to exist in cerebellar granule cells . These studies also show that PBCM has greater affinity for the muscarinic m2 receptor than the muscarinic m3 receptor. Endocrinology, 1992 Nov, 131(5), 2271 - 8 Basic fibroblast growth factor modulates insulin-like growth factor-I, its receptor, and its binding proteins in hypothalamic cell cultures; Pons S et al.; Interactions between different growth factors may be important in the regulation of cell growth and differentiation in the nervous system . For instance, basic fibroblast growth factor (bFGF) regulates neuroblast division through a mechanism probably involving insulin-like growth factor-I (IGF-I) . In this regard, we previously found that simultaneous addition of both factors produces an additive effect on survival and differentiation of hypothalamic neuronal and glial cells in culture . To further analyze these interactions, we explored the influence of bFGF on IGF-I, its membrane receptor, and its binding proteins in hypothalamic cells . We also tested the effects of IGF-I on its own receptor and binding proteins (IGFBPs) to determine the specificity of bFGF's actions . Treatment of neuronal and glial cultures with bFGF produced an increase in IGF-I receptors, without changing their affinity, together with an increase in the apparent M(r) of the receptor . On the other hand, IGF-I elicited a down-regulation of its own receptor in both neurons and glia, without modifying its affinity . Treatment with bFGF also produced a marked differential effect on the IGFBPs secreted by the cells . While IGFBP levels in neuronal cultures were greatly increased by bFGF, their production by glial cells was inhibited . On the other hand, IGF-I increased the amount of IGFBPs in both types of cells . Finally, addition of bFGF to the cultures elicited a dose-dependent increase in the release of IGF-I to the medium, but only a moderate increase in cellular IGF-I content, in both neurons and glia . We conclude that bFGF strongly modulates IGF-I, its receptors, and its binding proteins in the two major cell types of the hypothalamus . These findings reinforce the possibility that IGF-I and/or its receptors and binding proteins are involved in the trophic effects of bFGF on developing brain cells. Mutat Res, 1992 Nov, 283(3), 215 - 9 Cytogenetic effects of sodium azide encapsulated in liposomes on heteroploid cell cultures; Raicu P et al.; Lipid vesicles (liposomes) have been shown to be a useful vehicle for the delivery of a variety of compounds to cultured cells . Using multilamellar vesicles (MLV) and small unilamellar vesicles (SUV) we were able to deliver the classical mutagen, sodium azide, into human heteroploid HEp-2 cells . With this method sodium azide is not diluted in culture medium, but it is 'focused' into cells, producing chromosomal aberrations and other major genetic damages . Our results indicate that liposomes are suitable vectors for introducing clastogenic substances into cultured human cells. Zhonghua Yi Xue Za Zhi, 1992 Nov, 72(11), 667 - 9, 702 {Effects of prostaglandin E2 on growth and function of osteoblasts in human cell culture in vitro}; Peng Q; The effects of prostaglandin E 2 (PGE2) on the differentiation and proliferation of osteoblasts (human fetal bone-cells) cultured in serum-free medium were investigated by assays of alkaline phosphatase (ALP) activity, intracellular cyclic AMP level and collagen synthesis in the cells . The results suggested that PGE2 in physiologic concentration stimulated the differentiation of osteoblasts in vitro, and might be involved in bone formation in vivo. Microb Pathog, 1992 Nov, 13(5), 411 - 6 Suppression of LPS-inducible cytotoxicity in cytomegalovirus-infected THP-1 monocytic cell cultures does not correlate with a decrease in TNF-alpha antigen; Turtinen LW et al.; We document suppression of tumor necrosis factor alpha (TNF-alpha)-associated cytotoxic activity in a human monocytic cell line (THP-1) infected with the mycoplasma free human cytomegalovirus (CMV) strain AD169 . Addition of lipopolysaccharide (LPS) to cell cultures that had been infected with CMV for 24 h resulted in a significant reduction in released cytotoxic activity to mouse L929 cells at 3-22 h post-LPS compared with mock-infected cultures . However, using an ELISA to measure TNF-alpha antigen levels in these culture supernatants, we found infected cultures had significantly higher TNF-alpha antigen levels than in mock-infected cultures following LPS induction . CMV alone also induced TNF-alpha release and possibly TNF-alpha inhibitor(s) which may have blocked TNF-alpha associated cytotoxic activity in CMV-infected THP-1 cell culture supernatants. Vet Microbiol, 1992 Nov, 33(1-4), 361 - 6 An investigation of the effect of antisense RNA gene on bovine leukaemia virus reproduction in cell culture; Murovska MF et al.; A possible approach to control of bovine lymphoproliferative disease caused by bovine leukaemia virus (BLV) may be the development of an "antiviral information immunity" based on the effect of anti-sense RNA (asRNA) . A numbers of constructs were obtained, under control of various promotors (herpesvirus thymidine kinase, T-antigen SV40 promoter), carrying as DNA against gene X, the expression product of which is a transactivator of viral transcription from the BLV LTR promotor . As a model system for the analysis of antiviral activity of constructs developed, cloned continuous cell lines of BLV-producing FLK cells were used . The level of BLV expression in cells transfected with the constructs was determined by various parameters . Differences were detected in different clones obtained from non-transfected cells, as well as variation between transfected clones, as measured by reverse transcriptase, competitive radio-immunoassay for BLV p24, the viral particle count on agar membrane, and the tumorigenicity for nude mice . The differences in inhibition of expression of BLV genes and their products may be explained in terms of the site of integration of asDNA and the number of integrated copies. Vet Microbiol, 1992 Nov, 33(1-4), 239 - 48 Infection of ovine fetal brain cell cultures with cytopathogenic and non-cytopathogenic bovine viral diarrhoea virus; Hewicker-Trautwein M et al.; The in vitro cell tropism of non-cytopathogenic (ncp) and cytopathogenic (cp) bovine viral diarrhoea virus (BVDV) was studied in primary dissociated brain cell cultures derived from ovine fetuses of different gestational ages . The cell types infected were identified by double immunofluorescence using antibodies against BVDV and cell type-specific markers . In cultures infected with ncp BVDV viral antigen was present in neurofilament (NF 200 kDa)-positive neurons, glial fibrillary acidic protein (GFAP)-positive astrocytes and fibronectin-expressing cells . Estimation of the percentages of individual cell types infected with ncp BVDV indicated a tropism for NF 200-positive neurons . In cultures infected with cp BVD virus cytopathic changes were observed beginning at 40 hours post infection . Viral antigen was present in vacuolated NF 200-, GFAP- and fibronectin-positive cells . In comparison with non-infected control cultures a considerable reduction of the number of the different cell types was seen. Virus Res, 1992 Nov, 26(2), 113 - 25 Modifications of the 5' untranslated region of foot-and-mouth disease virus after prolonged persistence in cell culture; Escarmis C et al.; The nucleotide sequence of the 5'-untranslated region (5'UTR) of the genome of foot-and-mouth disease virus (FMDV) R100, rescued after 100 passages of persistently infected BHK-21 cells, has been compared with that of the parental FMDV C-S8c1 . The nucleotide sequence divergence between the two viruses in heteropolymeric regions is 1% . The few mutations located at the 5'-most terminal region (S fragment) and at the internal ribosome entry site (IRES) do not appear to affect significantly the tight secondary structure predicted for these RNA segments . Comparison of the 5'UTR of C-S8c1 or R100 RNA with that of other FMDV serotypes and subtypes indicates the presence of block deletions (or insertions) which do not correlate with the serological classification of FMDV . Remarkably, FMDV R100, a virus highly attenuated for mice and cattle, contains a polyribocytidylate (poly C) tract of about 420 nucleotides, 145 residues longer than its parental, virulent FMDV C-S8c1 . This long poly C of R100 RNA includes a few uridine residues interspersed at fairly regular intervals . This is the longest highly homopolymeric tract described in a viral genome and, to our knowledge, in any informational biomolecule. Cell Growth Differ, 1992 Nov, 3(11), 791 - 802 Expression of the HPV16 E7 gene generates proliferation in stratified squamous cell cultures which is independent of endogenous p53 levels; Blanton RA et al.; Monolayer cultures of human foreskin and ectocervical epithelial cells were infected with retroviral vectors expressing HPV16 oncogenes, selected for G418 resistance, and cultured organotypically so that they reformed the fully differentiated, stratified squamous tissues from which they were originally derived . Expression of HPV16 E7 prevented cell cycle withdrawal in the suprabasal layers of these stratified cultures but had no effect on terminal differentiation . Cultures expressing E7 alone and those coexpressing E6 and E7 were identical in terms of suprabasal proliferation and terminal differentiation, but they differed in expression of the endogenous tumor suppressor protein p53 . Immunohistochemically detectable p53 protein localized to the proliferative compartment in normal and E7-containing cultures but was undetectable in those cultures which coexpressed E6 and E7 . This result suggests that E7-induced suprabasal proliferation is independent of the steady-state level of p53. Neurologia, 1992 Nov, 7(9), 247 - 53 {Multiple sclerosis: IL-2, IFN-tau and PGE2 secretion in mononuclear cell cultures stimulated with PHA and the effect of these cytokines on oligodendroglial cells}; Sierra A et al.; The production of interferon-tau (IFN-tau), interleukin-2 (IL-2) and prostaglandin-E2 (PGE2) in peripheral blood mononuclear cells (PBMC) stimulated with phytohemagglutinin (PHA) and the repercussion which these cytokines have on the growth and activity of the 2', 3' and cyclonucleotide-3'-phosphohydrolase (CNP) of cultures of rat oligodendrocytes were analyzed . The study was carried out in a group of patients (20 with active disease, 23 in remission) with defined multiple sclerosis (MS), a group of subjects with other central nervous system diseases (OCNSD) and a group of 20 healthy (HS) . Increases in PGE2 were found in PBMC cultures of patients with MS (p < 0.0005, ANOVA test) and the production of PGE2 in patients with active MS correlated positively (R2 = 0.743, p = 0.02) with CNP activity in the oligodendroglial cultures . These results suggest that PGE2 may influence in the re-myelinization process. J Clin Invest, 1992 Nov, 90(5), 1944 - 51 Interleukin-2 and interleukin-2 receptor expression in human corticotrophic adenoma and murine pituitary cell cultures; Arzt E et al.; The production of IL-1 and IL-6 by pituitary cells has recently been demonstrated . In this study we investigated the expression of IL-2 and its receptor (IL-2R) by pituitary cells of different species . In Northern blots, a single hybridizing band of 1 kb, identical to that in normal stimulated lymphocytes, was obtained with specific IL-2 probes . In the mouse AT-20 pituitary tumor cell line, IL-2 mRNA expression was detected after stimulation with corticotropin-releasing hormone or phorbol myristate acetate . In human corticotrophic adenoma cells, basal IL-2 mRNA expression as well as IL-2 secretion were further stimulated by phorbol myristate acetate . Both adenoma and AtT-20 cells showed detectable amounts of IL-2R mRNA and by immunofluorescence, IL-2R membrane expression . In addition, dual immunofluorescence studies in rat anterior pituitary cells demonstrated colocalization of IL-2R with ACTH-positive cells and other cell types expressing the receptor . In addition to the action of lymphocyte-produced IL-2, this cytokine may have a paracrine or autocrine regulatory role within the pituitary . It remains to be established whether IL-2 production occurs in the normal pituitary or is intrinsic to the process of tumor development of these cells . IL-2 may be involved in the growth control of pituitary cells. Endocrinology, 1992 Nov, 131(5), 2173 - 81 Effect of epidermal growth factor on inhibin secretion in human placental cell culture; Qu J et al.; The effect of epidermal growth factor (EGF) on inhibin secretion was investigated in a primary culture of human placental cells . Dissociated cells were cultured with EGF, FSH, 8-Br-cAMP, and two agents known to increase intracellular cAMP . Inhibin level in the culture medium was measured by immunoenzymatic assay . Addition of EGF (0.1-1000 ng/ml) in the cell culture induced a dose-dependent increase of inhibin levels in the medium after 2 days of culture . Greater response of placental cells to EGF in the inhibin secretion occurred at the doses of 10-1000 ng/ml, where inhibin levels in the medium increased by 84.9-111.5% compared to the control (P < 0.01) . FSH stimulated the inhibin secretion in the placental cells . EGF combined with FSH resulted in a greater response of placental cells in inhibin secretion . Addition of FSH (30 ng/ml) and EGF (0.1-1000 ng/ml) in the culture induced inhibin levels significantly higher than that of either FSH alone or EGF alone (P < 0.01) . The effect of EGF on inhibin secretion was closely correlated with the seeding density of trophoblasts and the time course of culture . Obvious effect of EGF was found at the number of 1-2 x 10(6) cells per well and after 36-48 h of culture . Addition of 8-Br-cAMP, cholera toxin, or forskolin in the culture increased the inhibin levels more than 6-fold, 5-fold, and 2-fold, compared to the controls, respectively . When EGF combined with one of these agents was added in the culture, the inhibin in the medium increased to a level higher than those with the individual agents alone . EGF resulted in an increase in basal and cAMP induced human CG secretions in the trophoblasts in a similar manner as in the inhibin secretion . However, the effect of EGF on the proliferation of trophoblasts was not observed by measurements of the cell growth with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and DNA content in the cells with fluorescence spectrophotometry . Morphological study showed that EGF induced trophoblasts to differentiate and form syncytium . These data suggest that EGF stimulates inhibin secretion in human placental cells in vitro . EGF and its interaction with other hormones or growth factors may play an important role in the complicated hormonal regulation during human pregnancy. Lik Sprava, 1992 Nov-Dec, (11-12), 114 - 7 {Preclinical trials of polyplatillen, the antitumor activity of a complex platinum compound with DNA on a leukemia P388 model in a HEp-2 cell culture (1)}; Shalimov SA et al.; The authors studied the antitumour activity of a new complex platinum compound (DDP-DNA) in mice with leukemia P-388 and in cell culture . DDP-DNA was introduced intraperitoneally 24 hours after inoculation of 2 x 10(6) tumour cells . It was established that by its antitumour activity DDP-DNA was not inferior then DDP . The antiproliferative activity of nontoxic doses of the preparation in cell culture has been shown. Pigment Cell Res, 1992 Nov, 5(5 Pt 1), 224 - 9 Extracellular matrix constituents and pigment cell expression in primary cell culture; Fukuzawa T et al.; Three types of pigment cells were isolated and cultured from larval Rana pipiens, and their attachment, maintenance, and proliferation were examined in the presence of extracellular matrix constituents (ECMs) in primary cell culture . The initial profile of pigment cell types present on day 2 of culture reflects the relative attachment of the cells to the dishes . Changes in the numbers of cells present after day 2 reflects the influence of factors present in the culture media on the maintenance, proliferation, or detachment of each type of pigment cell . Fetal bovine serum (FBS) promoted melanophore expression, but inhibited iridophore expression . FBS had no effect on xanthophores . In contrast, ventral skin conditioned medium (VCM), which contains melanization inhibiting factor, strongly stimulated iridophore expression, while it markedly inhibited melanophore expression . VCM had little effect on xanthophores . Of the ECMs tested, collagen type I had no effect on pigment cells . Fibronectin slightly inhibited melanophore expression, while it moderately stimulated iridophores and xanthophores . The stimulatory effect of fibronectin was not as strong as that of FBS or VCM . Laminin was also tested; however, it did not allow pigment cells to attach to the dishes, at least under the culture conditions utilized . The results of these experiments are discussed in terms of the general mechanisms of pigment pattern formation. Arch Oral Biol, 1992 Nov, 37(11), 945 - 52 Collagen gene expression in human dental pulp cell cultures; Kuo MY et al.; Pulp cells from human permanent molars were isolated and established in culture; 40% showed positive alkaline phosphatase staining . When incubated with 50 micrograms/ml of ascorbic acid and 10 mM of beta-glycerophosphate, the cells formed a mineralized extracellular matrix; they could thus have the potential to differentiate into odontoblast-like cells in vitro . Collagen synthesis was analysed by SDS interrupted gel electrophoresis, Northern blot and slot blot: the cells produced predominantly (approximately 99%) type I collagen and only trace amount of type III collagen . The ratio of alpha 1 (I) to alpha 2(I) procollagen chains was about 68:32, indicating that no significant amount of collagen type I trimer was synthesized in this system . The ratios of alpha 1(I), alpha 2(I) and alpha 1(III) procollagen mRNAs were about 61:25:1; these were compatible with the ratios of corresponding procollagen alpha chains . In addition, a novel 5.8 kb pro alpha 1(III) mRNA was detected . These observations indicate that collagen synthesis in these cultured pulp cells was regulated at the transcriptional level. Biochem Biophys Res Commun, 1992 Oct 30, 188(2), 727 - 33 Single-stranded DNA of 5'-upstream region of the rolC gene interacts with nuclear proteins of carrot cell cultures; Suzuki A et al.; Using the gel retardation assay, proteins of carrot cells capable of binding to a single-stranded DNA of 5'-upstream region of the rolC gene were found . From competition experiments, these DNA-protein interactions were specific to single-stranded nucleotide sequence of Ava S fragment (from -94 bp to +23 bp relative to the transcription initiation site) . Methylation interference experiments showed that G residue at the position of -41 bases on the bottom strand was important for DNA-protein binding . This residue was located between CAAT box and TATAA box . Such specific interaction between single-stranded DNA and nuclear proteins may play a role in transcription by RNA polymerase II. Neurosci Lett, 1992 Oct 26, 146(1), 69 - 71 Hypothermia protects astrocytes during ischemia in cell culture; Shuaib A et al.; A mild decrease in temperature (2-3 degrees) can result in marked attenuation of ischemic neuronal damage in living animals . We now report the protective effects of hypothermia in an astrocyte with simulated ischemia in cell culture system . Hypothermia when used during ischemia showed significant reduction of damage . Brief episodes of post-ischemic hypothermia were not protective whereas more prolonged post-ischemic hypothermia showed moderate protection . Cell culture systems may prove to be useful tools to study the mechanisms of hypothermic protection during ischemia. Brain Res, 1992 Oct 23, 594(1), 91 - 8 Characterization of dynorphin-containing neurons on dissociated dentate gyrus cell cultures; He XP et al.; In the dentate gyrus, the synthesis of the opioid peptide, dynorphin, is modulated by a variety of stimuli . In order to elucidate the cellular and molecular mechanisms regulating the synthesis of dynorphin in the hippocampus, we have established a routine primary cell culture of dentate granule neurons and identified granule-like neurons by a characteristic marker, dynorphin, in these cultures . Cultures were prepared from 7-day-old rat pups and maintained in medium with 2% fetal bovine serum . These cultures contained approximately 20% neurons and survived for over 4 weeks . After 2 weeks in culture, neurons expressing dynorphin-A and its messenger RNA were detected using immunocytochemistry and in situ hybridization, respectively . In dentate cultures, enkephalin-, cholecystokinin-, neuropeptide Y- and substance P-positive cells were observed in addition to dynorphin-positive cells with immunocytochemistry . The results suggest that dentate gyrus cell cultures provide a valid in vitro model for studying molecular mechanisms regulating prodynorphin gene expression. Brain Res, 1992 Oct 16, 593(2), 307 - 10 Preferential activation of {3H}phorbol-12,13-dibutyrate binding by AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) in neonatal striatal cell cultures; McMillian M et al.; Activation of excitatory amino acid receptors increased {3H}phorbol-12,13-dibutyrate ({3H}PdBu) binding in four week cultures of striatal cells from postnatal day 7 rat pups (PN7), and in PN7 cells co-cultured the fourth week with striatal cells from postnatal day 1 rat pups . Kainate (KA), trans-1-amino-cyclopentyl-1,3-dicarboxylate (ACPD), and N-methyl-D-aspartate (NMDA) increased {3H}PdBu binding equally in both types of cultures, but alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) increased binding by 3-fold in the co-cultures . Thus, {3H}PdBu binding in these two types of striatal cultures offers a simple model system for studying the regulation of AMPA/KA receptor responses. J Immunol, 1992 Oct 15, 149(8), 2689 - 94 Identification of IL-8 as a locomotor attractant for activated human lymphocytes in mononuclear cell cultures with anti-CD3 or purified protein derivative of Mycobacterium tuberculosis; Wilkinson PC et al.; On culture of human blood mononuclear cells for 24 to 48 h with anti-CD3 (aCD3) or purified protein derivative of Mycobacterium tuberculosis, chemoattractants are released into the medium which induce polarization and locomotion of activated (G1) lymphocytes but not resting lymphocytes . Here we show that, during a period of up to 72 h of culture, IL-8 is released in nanomolar quantities into the supernatant and that the lymphocyte chemoattractant activity of these supernatants is inhibited by incubation with anti-IL-8 . Examination of the cultured mononuclear cells by immunofluorescence suggests that many monocytes, but almost no lymphocytes in aCD3 cultures contain IL-8 in cytoplasmic organelles, yet few monocytes direct from blood stained for IL-8 . IL-8 is an attractant for only a small proportion (ca 10%) of lymphocytes direct from blood . The proportion of responding cells is increased after culture for 24 to 48 h in aCD3 or purified protein derivative of Mycobacterium tuberculosis, and these are a phenotypically distinct subpopulation consisting of large lymphocytes enriched for CD45RO . These cells respond to their own culture supernatants and to IL-8 in polarization assays and by invasion of collagen gels into which the attractants are incorporated . They also show orientation to a source of IL-8 in a chemotactic gradient . These responses are consistent with in vivo observations that the lymphocytes which migrate selectively into inflammatory sites are activated . The fact that many lymphocytes do not respond to IL-8 may reflect the diversity of migratory pathways shown by lymphocytes in vivo, the locomotion of small, recirculating, lymphocytes being regulated by other, unknown, locomotor stimuli. Ann N Y Acad Sci, 1992 Oct 13, 665, 259 - 73 Three-dimensional cell cultures mimic tissues; Saltzman WM et al.; Three-dimensional cell culture using gels of type I collagen is a flexible method for studying cell behavior in a tissuelike environment . With only small changes in the basic protocol, we were able to encapsulate neutrophils, hepatocytes, and PC12 cells . As demonstrated by cell-specific assays for migration, protein secretion, and growth factor induction, the encapsulated cells were viable and functional . In future studies, we will focus on using these cell cultures to study cell movement, cell growth, and cell function in carefully controlled tissuelike environments. J Nutr, 1992 Oct, 122(10), 1971 - 8 Low density lipoprotein receptor activity is modulated by soybean globulins in cell culture; Lovati MR et al.; The effects of major storage globulins from soybean on cholesterol homeostasis were investigated in vitro and in vivo systems . The low density lipoprotein (LDL) uptake and degradation was studied both in human skin fibroblasts (HSF) and in a human hepatoma cell line (Hep G2) . In Hep G2 cells a dose-dependent increase of both uptake and degradation of 125I-LDL was induced by the 7S globulin, whereas the 11S globulin exerted a lesser effect that was not dose-related . In HSF cells the 11S globulin increased the uptake of 125I-LDL to a greater extent than did 7S globulin; in this cell line, LDL degradation was not stimulated by either of the globulins . Rats fed a casein-cholesterol diet were treated daily with the 11S or 7S globulins for 2 wk . The administration of soybean globulins significantly reduced cholesterolemia (-35 and -34% with 7S and 11S globulins, respectively, vs . controls) . Liver membrane preparations from the casein-cholesterol-fed rats showed a nonsignificant increase in the maximal binding of labeled cholesterol-rich lipoprotein fraction (beta-VLDL) to high affinity receptors. Contraception, 1992 Oct, 46(4), 399 - 406 Determination of carcinogenic potency of alkytoxynol-741 (AP-741) by rat peritoneal cell cultures; Qin J et al.; The carcinogenic potency of AP-741 was tested in rats using the Nashed method of rat peritoneal cell short-term carcinogenic test . N-methyl-N-nitro-N'-nitrosoguanidian (MNNG) was used as positive control; saline and nonoxynol-9 (NP-9) were used as negative control . Two doses of AP-741 (4 mg/kg and 40 mg/kg equivalent to 4 and 40 times human doses) were tested . The result showed that no colonies of more than 9 cells were seen in the saline and NP-9 groups, and the two dose groups of AP-741 . However, 12 +/- 8.3 colonies (9-29 cell/colony) and 4.5 +/- 4.2 colonies (30-300 cell/colony) were seen in the MNNG group . According to the Nashed criterion, we can say MNNG has potential carcinogenesis, while AP-741 does not have any potential carcinogenesis and its use as a vaginal contraceptive drug is safe. Differentiation, 1992 Oct, 51(2), 113 - 9 Gestation stage-specific frequency of adipogenic cells in Syrian hamster cell cultures; Ueo H et al.; High frequencies (up to 50%) of spontaneous adipocyte differentiation are observed in cultures of 9 day gestation Syrian hamster embryos (E9 cells) within six to eight population doublings after primary culture . This is in contrast to the absence of adipogenic cells in primary cultures derived from later gestation age Syrian hamster tissue . In addition, E9 primary cultures contain a transient subpopulation of presumptive mesenchymal stem or progenitor cells that lack density dependent inhibition of growth {contact-insensitive (CS-) cells} . Analysis of the temporal pattern of expression of the CS- and adipocyte phenotypes during the proliferative life span of E9 cells demonstrates that maximal expression of the CS- phenotype precedes maximal expression of adipocyte differentiation . In addition, lipid accumulation appears to occur primarily, if not exclusively, in the contact-sensitive (CS+) cells that are derived from CS- cells . These observations suggest that primary E9 cultures contain either adipoblasts or primordial mesenchymal cells that become determined to the adipocyte lineage early during the in vitro life span of the cultures, and that the CS- phenotype may be a marker for these earlier developmental cell stages. Eur J Cell Biol, 1992 Oct, 59(1), 166 - 75 Low molecular mass heat-shock proteins of a light-resistant photoautotrophic cell culture; Knack G et al.; Two low molecular mass heat-shock proteins (HSPs) of photoautotrophic cell culture (Chenopodium rubrum) have been cloned, sequenced and compared to published sequences . One of these HSPs (23.3 kDa) is posttranslationally transported into chloroplasts and shares homology with the other heat-shock proteins in the last third C-terminal region of the protein, but has a relatively unique sequence in the other two thirds . The correspondent small cytosolic protein of 18.3 kDa is related to all known small HSPs but has a unique DNA-binding domain that has not been described so far in the group of small cytosolic HSPs, it might represent a HSP which is translocated into the nucleus. AIDS Res Hum Retroviruses, 1992 Oct, 8(10), 1815 - 21 HIV-1-induced cytopathogenicity in cell culture despite very decreased amounts of fusion-competent viral glycoprotein; Bosch V et al.; In order to examine the potential role of env-induced membrane fusion in the cytopathogenic properties of HIV-1 in cell culture, the effects of mutations within the proteolytic cleavage site of gp160, which result in a reduction but not a complete absence of proteolytic processing have been further studied . Cells expressing the mutant glycoproteins were shown to be severely reduced in their capacity to form syncytia . However, viruses encoding these glycoproteins could infect cell culture cells, albeit with delayed kinetics, and, at late infection time points, resulted in complete cytolysis of the infected culture . Since amplification by polymerase chain reaction and direct sequencing of the DNA in the infected cultures confirmed the presence of the mutant and the absence of revertant DNA, this shows that the amount of fusion competent viral glycoprotein does not influence HIV-1 cytopathogenicity, but rather that other parameters must be involved in inducing cell death. J Bone Miner Res, 1992 Oct, 7(10), 1211 - 9 beta-Glycerophosphate-induced mineralization of osteoid does not alter expression of extracellular matrix components in fetal rat calvarial cell cultures; Lee KL et al.; When fetal rat calvarial cells are cultured in medium containing vitamin C, osteoid nodules develop after approximately 15 days of culture . Upon addition of an organic phosphate (beta-glycerophosphate, beta GP), these nodules mineralize . We have now used this system to explore the suggestion made by others that a negative feedback may exist between matrix mineralization on the one hand and the synthesis of alkaline phosphatase and bone matrix collagen on the other by analyzing the synthesis of these proteins and the levels of their mRNAs in mineralizing and nonmineralizing cultures . Our results indicate that in the osteoid nodule-bone nodule system, matrix mineralization did not affect the mRNA levels for osteopontin, type I collagen, bone sialoprotein, or osteocalcin . Synthesis of total protein and collagen and the osteocalcin content of culture media were also not different in the mineralizing and nonmineralizing cultures . However, alkaline phosphatase mRNA was increased in early mineralizing cultures and alkaline phosphatase activity in the cell layer was also increased in mineralizing cultures . Thus, the hypothesis that a direct negative feedback exists between mineralization and matrix protein synthesis is not supported by our experiments. J Anim Sci, 1992 Oct, 70(10), 3014 - 23 The effect of the beta-adrenergic agonist clenbuterol on growth and protein metabolism in rat muscle cell cultures; McMillan DN et al.; Cultures were established from neonatal rat muscle cells, satellite cells, and L6 myoblasts and changes in protein metabolism were determined as development proceeded . For all three cell types, culture protein content increased with increasing myotube content . The beta-adrenergic agonist clenbuterol (added to a final concentration of 10(-7) M) significantly stimulated fusion (as indicated by creatine kinase activity) in neonatal muscle cultures and also increased culture protein content . This was associated with a stimulation in both the fractional (ks, percentage/day, +13%, P less than .05) and absolute (As, micrograms/day, +19%, P less than .05) rates of protein synthesis within 24 h after drug administration . At 48 h, As was increased by 42% above that of controls (P less than .01) . In contrast, in satellite cell cultures, clenbuterol had no consistent effects on either protein accretion, creatine kinase activity, or protein synthesis (ks and As) . Similarly, the drug had no stimulatory effect on protein synthesis and protein accretion in L6 myoblast or L6 myotube cultures (and no effect in neonatally derived fibroblast cultures) . It is concluded that the fusion response to clenbuterol and, therefore, changes in protein metabolism and protein accretion are greatly dependent on the origin and genetic integrity of muscle cells. J Neuroimmunol, 1992 Oct, 40(2-3), 231 - 4 Myelin gene expression during demyelination and remyelination in aggregating brain cell cultures; Matthieu JM et al.; Remyelination can be studied in aggregating rat brain cell cultures after limited demyelination . Demyelination was induced using a monoclonal antibody against myelin/oligodendrocyte glycoprotein (MOG mAb), in the presence of complement . De- and remyelination were assessed by measuring myelin basic protein (MBP) . Two days after removing the MOG mAb, MBP levels reached 50% of controls and after 7 days 93% . During this period, cell proliferation determined by {14C}thymidine incorporation was similar in remyelinating and control cultures . Hormones and growth factors were tested for possible stimulatory effect on remyelinating cultures . Bovine growth hormone (bGH), triiodothyronine (T3), basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF) did not improve remyelination . Only epidermal growth factor (EGF) increased the level of remyelination . PDGF increased the rate of cell proliferation in both control and remyelinating cultures . A significant proportion of oligodendrocytes entered the cell division cycle and were not available for remyelination . The results obtained with PDGF and FGF (inhibition) support the idea that a pool of progenitor cells was still present and able to proliferate and differentiate into myelinating oligodendrocytes . The levels of myelin protein mRNAs were investigated during de- and remyelination . During demyelination, myelin protein mRNA levels decreased to approximately 50% of control cultures and returned to normal during remyelination . These preliminary results indicate that normal levels of gene transcription are sufficient to meet the increased need for newly synthesized myelin proteins during remyelination. J Biotechnol, 1992 Oct, 26(1), 29 - 62 Bioconversion of naturally occurring precursors and related synthetic compounds using plant cell cultures; Pras N; The nearly unlimited enzymatic potential of cultured plant cells can basically be employed for bioconversion purposes . Plant enzymes are able to catalyze regio- and stereospecific reactions and can therefore be applied to the production of compounds of pharmaceutical interest . Naturally occurring as well as related synthetic compounds may be used as precursors . A review of the current status of such bioconversions is given . It includes the performance of bioconversions by freely suspended and immobilized plant cells or enzyme preparations . In addition, the kinetic aspects of immobilized plant cells are discussed . Special attention is paid to the bioconversion of poorly or water insoluble precursors . Finally, a model scheme for the development of a commercially available drug, produced by bioconversion, and perspectives are discussed. Acta Virol, 1992 Oct, 36(5), 483 - 7 A method for the preparation of purified antigens of coxsackievirus B3 from a large volume of cell culture supernatant; Novotny J et al.; A simple procedure was used for the concentration and partial purification of coxsackievirus B3 (Nancy strain) . For a large-scale production of virus . Vero cells grown in roller bottles were used . Virus concentrate from a large volume of cell culture supernatant was prepared by precipitation with 6% (w/w) polyethylene glycol . This crude antigen was further purified by banding in cesium chloride gradient using ultracentrifugation . The infectivity and haemagglutination activity of virus were checked up during the whole procedure and the final recovery of infections virus was about 60%. Mol Pharmacol, 1992 Oct, 42(4), 575 - 83 kappa-Opioid inhibition of {3H}dopamine release from rat ventral mesencephalic dissociated cell cultures; Smith JA et al.; The present study investigated the effect of opioids on {3H}dopamine release from mixed neuronal-glial cell cultures of embryonic rat ventral mesencephalon . Each of the major morphological types of dopaminergic cell was represented in these cultures . These cells exhibited specific uptake of {3H}dopamine, which was subsequently released, in a calcium-dependent manner, in response to a double pulse of elevated extracellular potassium . Spontaneous and potassium-evoked {3H}dopamine release was inhibited by kappa- but not mu- or delta-opioid agonists . The selective kappa 1 agonist (5 alpha, 7 alpha, 8 beta)-(-)-N-methyl-N-{7-(1-pyrollidinyl)-1-oxaspiro(4,5)- dec-8-yl}benzeneacetamide (U69593) produced a dose-dependent inhibition of dopamine release . The effect of U69593 was blocked by the nonselective opiate antagonist naloxone and the selective kappa opioid antagonist norbinaltorphimine . kappa-Opioid inhibition of potassium-evoked {3H}dopamine release was maintained in the presence of tetrodotoxin . These results suggest that functional kappa receptors, modulating dopamine release, are localized on the terminals of dopaminergic neurons. J Neuroimmunol, 1992 Oct, 40(2-3), 295 - 303 Developmental effects of basic fibroblast growth factor and platelet-derived growth factor on glial cells in a three-dimensional cell culture system; Honegger P et al.; In order to study peptide growth factor action in a three-dimensional cellular environment, aggregating cell cultures prepared from 15-day fetal rat telencephalon were grown in a chemically defined medium and treated during an early developmental stage with either bovine fibroblast growth factor (bFGF) or platelet-derived growth factor (PDGF homodimers AA and BB) . A single dose (5-50 ng/ml) of either growth factor given to the cultures on day 3 greatly enhanced the developmental increase of the two glia-specific enzyme activities, 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) and glutamine synthetase (GS), whereas it had relatively little effect on total protein and DNA content . Distinct patterns of dose-dependency were found for CNP and GS stimulation . At low concentrations of bFGF (0.5-5 ng/ml) and at all PDGF concentrations applied, the oligodendroglial marker enzyme CNP was the most affected . A relatively small but significant mitogenic effect was observed after treatment with PDGF, particularly at higher concentrations or after repetitive stimulation . The two PDGF homodimers AA and BB were similar in their biological effects and potency . The present results show that under histotypic conditions both growth factors, bFGF and PDGF, promote the maturation rather than the proliferation of immature oligodendrocytes and astrocytes. Mem Inst Oswaldo Cruz, 1992 Oct-Dec, 87(4), 565 - 74 Replication of dengue viruses in mosquito cell cultures--a model from ultrastructural observations; Barth OM; Mosquito cell cultures infected with human sera from dengue-1 and dengue-2 outbreaks, started in Rio de Janerio by 1986 and 1990 respectively, were examined by electron microscopy at different times post the infection of cell cultures . More information was obtained about cell penetration of virus particles in the presence or not of antibodies, their pathway inside the cells, replication mode and exist . Infectiveness of the virus at those different stages can only be attributed to the particles appearing inside the trans-Golgi vesicles; most of all newly formed virus particles remain inside the RER-derived cell vesicles or inside lysosomes, even during cell lysis . Groups of larger particles, 65-75 nm in diameter at dengue-2 infections, persist during cell passage . The large amounts of smooth membrane structures, as vesicles or tubules inside the RER, are attributed to a cell response to viral infection. Acta Obstet Gynecol Scand, 1992 Oct, 71(7), 502 - 5 Effect of cortisol on the secretion of testosterone and estradiol-17 beta by human granulosa-luteal cell cultures . A model system for analyzing hormonal alterations in female athletes; Tsai L et al.; The combination of hypercortisolism and usually low androgen and estrogen levels is frequently observed in female long distance athletes . In order to find a useful model system for studying the underlying mechanisms, the following studies were performed . The effect of cortisol on the secretion of testosterone (T) and estradiol-17 beta (E2) by human granulosa-luteal cells was studied in vitro in cultures of cells recovered from mature follicles of gonadotrophin stimulated women (participating in the IVF program) . Following 24 hours of culture in tissue culture medium without hormonal additives, the granulosa-luteal cells were incubated for 6 hours in media with addition of 4-androstene-3,17-dione (A-4) as precursor and hMG and cortisol in different combinations . The secretion of T was significantly stimulated by cortisol but not by human menopausal gonadotrophin (hMG) . Cortisol, but not hMG, also increased the secretion of E2, although this effect was not statistically significant . These in vitro findings make a direct effect of cortisol upon ovarian sex steroid secretion less likely as the mechanism behind the subnormal sex steroid levels in female long distance athletes . Instead, inadequate gonadotrophic stimulation, related to hypothalamic amenorrhea, and/or a selective decrease in the adrenal secretion of precursor steroids, may be an explanation. Eur J Pharmacol, 1992 Oct 1, 227(2), 225 - 8 Proposed antagonists at GABAB receptors that inhibit adenylyl cyclase in cerebellar granule cell cultures of rat; Holopainen I et al.; The effects of various proposed GABAB receptor antagonists on baclofen-mediated inhibition of adenylyl cyclase were studied in cultured cerebellar granule cells from rat . (+/-)-Baclofen maximally inhibited adenylyl cyclase by approximately 60% of the basal enzyme activity with an EC50 value of 10 microM . 3-Aminopropane sulfonic acid (3-APS) and 5-aminovaleric acid (5-AVA) produced similar responses to that seen with (+/-)-baclofen . Saclofen reversed the action of (+/-)-baclofen, 50 microM, with a half maximal inhibitory concentration (IC50) of about 1.0 mM . The most effective antagonist in blocking the action of (+/-)-baclofen was 3-aminopropyl-diethoxy-methyl-phosphonic acid (CGP 35,348) . In the presence of (+/-)-baclofen, 50 microM, the IC50 for CGP 35,348 was 290 microM and its inhibitory constant (KA) was 180 microM . The agonist-like actions of 3-APS and 5-AVA were antagonized by CGP 35,348 suggesting that 3-APS and 5-AVA may act as weak agonists at the GABAB receptor that inhibits adenylyl cyclase . All antagonists tested, except the new compound CGP 35,348, have very low potencies at GABAB receptors that inhibit adenylyl cyclase, though these compounds have been quite effective at other GABAB receptor-mediated events . Thus, the GABAB receptor which inhibits adenylyl cyclase differs pharmacologically from other reported GABAB receptor/effector systems and supports the existence of multiple receptor subtypes. Gan To Kagaku Ryoho, 1992 Oct, 19(12), 2107 - 12 {Cell culture and its application--in vitro evaluation of anticancer activity using human tumor cell lines}; Tashiro T; Selective toxicity against cancer cells is a most important determinant for anticancer agents . Therefore, we have preferably evaluated anticancer effects in vivo using murine tumor models for several decades . Approximately 50 anticancer agents are currently available for clinical therapy, but very few agents are effective against some types of cancer . Much progresses in cell culture techniques resulted in establishment of various human tumor cell lines . Currently, we are able to use human tumor lines as well as murine ones for the examination of drug sensitivity . A number of assay methods to evaluate anticancer activity have been developed . In the beginning, growth inhibitory activity was evaluated by counting cell numbers after drug exposure . Then, human tumor clonogenic assay (HTCA) was designed to measure only proliferative cells . Recently colorimetric MTT assay and SRB assay in 96-well microplates were developed, which were adopted in the screening system in the NCI, based on a new idea, that is, disease-oriented screening (DOS) using about 60 human tumor cell lines . In this paper outline of each method was described, adding especially several comments on disease-oriented screening. J Cardiovasc Pharmacol, 1992 Oct, 20(4), 533 - 7 Progesterone potentiation of bupivacaine arrhythmogenicity in pentobarbital-anesthetized rats and beating rat heart cell cultures; Baum VC et al.; The effects of progesterone treatment on bupivacaine arrhythmogenicity in beating rat heart myocyte cultures and on anesthetized rats were determined . After determining the bupivacaine AD50 (the concentration of bupivacaine that caused 50% of all beating rat heart myocyte cultures to become arrhythmic), we determined the effect of 1-hour progesterone HCl exposure on myocyte contractile rhythm . Each concentration of progesterone (6.25, 12.5, 25, and 50 micrograms/ml) caused a significant and concentration-dependent reduction in the AD50 for bupivacaine . Estradiol treatment also increased the arrhythmogenicity of bupivacaine in myocyte cultures, but was only one fourth as potent as progesterone . Neither progesterone nor estradiol effects on bupivacaine arrhythmogenicity were potentiated by epinephrine . Chronic progesterone pretreatment (5 mg/kg/day for 21 days) caused a significant increase in bupivacaine arrhythmogenicity in intact pentobarbital-anesthetized rats . There was a significant decrease in the time to onset of arrhythmia as compared with control nonprogesterone-treated rats (6.2 +/- 1.3 vs . 30.8 +/- 2.5 min, mean +/- SE) . The results of this study indicate that progesterone can potentiate bupivacaine arrhythmogenicity both in vivo and in vitro . Potentiation of bupivacaine arrhythmia in myocyte cultures suggests that this effect is at least partly mediated at the myocyte level. Pharmacol Res, 1992 Oct-Nov, 26(3), 293 - 303 Nedocromil sodium modulates the function of long-term rat peritoneal mast cell cultures; Shalit M et al.; Long-term rat peritoneal mast cell (MC) cultures consisting of MC co-cultured with 3T3 fibroblasts (MC/3T3) were employed to study the effects of repeated and prolonged incubation with nedocromil sodium (10(-3) and 10(-5) M) on MC activation . When nedocromil sodium was added simultaneously with compound 48/80 to MC/3T3 on the first day of the experiment, it inhibited histamine release to the same extent as when added to the cultures a week later upon rechallenge . In other experiments activated MC/3T3 were incubated with nedocromil sodium for a week and on the last day of the experiment fresh nedocromil sodium was added simultaneously with compound 48/80 . Under these conditions the drug was as potent in inhibiting histamine release from the activated MC as it was in cultures incubated for a week with medium alone . In addition, preincubation of naive MC with nedocromil sodium for two days inhibited histamine release from these cells when activated for the first time . Salbutamol (10(-3) and 10(-5) M) exhibited a similar inhibitory effect to nedocromil sodium upon simultaneous incubation with MC/3T3 . However, prolonged incubation of salbutamol with MC/3T3 cultures resulted in tachyphylaxis . We conclude that nedocromil sodium is an effective MC stabilizing drug since it similarly inhibits histamine release from both primarily and secondarily challenged MC . Moreover this drug does not lose its efficacy upon prolonged incubation with MC. J Immunol, 1992 Sep 15, 149(6), 1905 - 11 Heterogeneity in antigen processing by different types of antigen-presenting cells . Effect of cell culture on antigen processing ability; Vidard L et al.; The ability of normal B cells, peritoneal macrophages, and splenic APC to process and present OVA to a panel of T-T hybridomas with different specificities was investigated . In all cases, B cells were less efficient than unfractionated splenocytes in presenting OVA or its peptides . However, when the presentation of native Ag was compared to the presentation of peptides, it was obvious that there were marked differences in the ability of these two APC populations to generate different epitopes from OVA . Leupeptin inhibits the processing of selected epitopes from native OVA differently when it was presented by spleen cells or B cells, suggesting that these two APC populations differ in their protease content . The effect of in vitro culture on the ability of splenic and peritoneal APC to process OVA was also investigated . Native OVA presentation by macrophages and spleen cells was affected by in vitro culture, more for some epitopes than for other epitopes . In contrast, presentation of exogenous peptides by paraformaldehyde-fixed APC was either not affected by previous culturing for 3 days, or very much improved . Altogether, these data demonstrate that different epitopes on the same protein may be independently and differentially processed by B cells and spleen cells . Furthermore, the precise peptides that are produced may vary with the physiologic state of the APC. J Comp Neurol, 1992 Sep 15, 323(3), 411 - 22 Growth properties of larval and adult locust neurons in primary cell culture; Kirchhof B et al.; We developed a cell culture system for thoracic neurons of fifth instar or adult locusts (Locusta migratoria) in order to obtain maximum visualization of cellular morphology and direct access to the neurons for electrophysiological analysis . The dissociated neurons regenerated new neurites in a serum-free defined culture medium, in which they remained viable for up to 3 weeks . Viability of the cells was confirmed by intracellular recordings demonstrating active membrane properties and action potentials . While the morphology of the cultured neurons is distinct from their in vivo counterparts, they retained some cellular surface properties and markers related to transmitter metabolism . Two factors influencing cellular morphology in vitro were identified in Locusta: 1) the presence of a primary neurite stump, and 2) membrane contacts between cells . Dissociated neurons of the locust species Schistocerca gregaria grown in a hemolymph-enriched medium showed a marked reduction in branching patterns and a tenfold increase in neurite length compared to neurons growing in a medium without hemolymph . This culture system could prove useful for identifying the action of hemolymph-derived growth factors. J Chromatogr, 1992 Sep 2, 579(2), 354 - 60 Determination of trimethoprim and its oxidative metabolites in cell culture media and microsomal incubation mixtures by high-performance liquid chromatography; van 't Klooster GA et al.; A high-performance liquid chromatographic method is presented for the determination of trimethoprim (TMP), 3'-hydroxy-TMP, 4'-hydroxy-TMP, alpha-hydroxy-TMP and two TMP N-oxides . The last two metabolites appear to decompose on liquid extraction . TMP and its oxidative metabolites are separated using a C18 radial-compression column and quantified by UV detection at 230 nm . Calibration curves are linear from 0.5 to at least 50 microM . The limit of detection is 0.05-0.15 micrograms/ml . In in vitro rat liver metabolism studies . 3'- and 4'-hydroxylation of TMP appear to be important metabolic pathways whereas TMP N-oxides are minor metabolites. Gan To Kagaku Ryoho, 1992 Sep, 19(11), 1935 - 40 {Cell culture and its application current methods for a synchronous culture of mammalian cells}; Ayusawa D; Synchronization of cells to various phases of the cell cycle in mammalian cells is crucial to analyze cell cycle progression and many other cellular functions . To date, various methods have been developed, such as mitotic selection, use of cell-cycle mutants, use of drugs which inhibit DNA replication (nucleoside analogue, excess thymidine, hydroxyurea, and aphidicolin), elutriation, deprivation of nutrients (amino acid, and serum), and new promising drugs of protein kinase inhibitors . Although above methods have both advantage and disadvantage, a practical and satisfactory method can be chosen from these method if taking into account goals of experiments and cell types to use . In near future, more powerful and reliable ones will be discovered since our understanding of the cell cycle has been increasing quite abruptly. Gematol Transfuziol, 1992 Sep-Oct, 37(9-10), 3 - 5 {Effect of hematopoietic and lymphoid cells on the stromal CFU colony formation in rabbit bone marrow cell cultures}; Gorskaia IuF et al.; Guinea pig and rabbit bone marrow and splenic cells with increasing cellular density suppress in vitro formation of fibroblast colonies by rabbit bone marrow clonogenic stromal cells . At the same time guinea pig bone marrow and splenic cells produce a stimulating effect on guinea pig bone marrow CFUf, but they are inhibited by rabbit splenocytes, although to a lesser extent than rabbit bone marrow CFUf . Rabbit blood platelets stimulate the growth of bone marrow CFUf of these animals . However, introduction into the culture of rabbit bone marrow cells combined with platelets eliminates the latter's growth-stimulating effect on stromal clonogenic cells of rabbit bone marrow . The results obtained have evidenced that guinea pig and rabbit bone marrow and lymphoid cell populations contain cells both stimulating and inhibiting CFUf proliferation, and that CFUf of varying animal species have different sensitivity to growth-stimulating and growth-inhibiting effects. Mol Biol (Mosk), 1992 Sep-Oct, 26(5), 1122 - 7 {Adducts of 3'-azido-2,3'-dideoxythymidine 5'-phosphate or 5'-phosphonate as inhibitors of cytopathic effect and transformation of cells under the influence of retroviruses in cell culture}; Fedorov II et al.; Inhibition of HIV-1- or HIV-2-induced cytopathicity and (Moloney) murine sarcoma virus (MSV)-induced cell transformation by amino acid and amino alcohol adducts of either 3'-azido-2',3'-dideoxythymidine 5'-monophosphate (AZTMP) or 5'-hydrogenphosphonate (AZTHP) were investigated . Both types of nucleotide adducts inhibited replication of HIV-1 and HIV-2 in MT-4 cells at a 1.5- to 3-fold higher EC50 (50% effective concentration) than AZT; and, also, selectivity indexes of these adducts were approximately 1.5 to 3-fold lower than that of AZT . The activity of the AZTMP and AZTHP adducts against MSV-induced transformation of C3H/3T3 cells was equal to or only slightly inferior than that of AZT, but their toxicity was 10-fold lower, so that their selectivity indexes were 2- to 7-fold higher . The nature of the aminoacyl component of the adducts significantly influence the antiretroviral activity of the test compounds. Hum Cell, 1992 Sep, 5(3), 292 - 7 {Use of 2-mercaptoethanol in cell culture}; Bannai S; Survival and growth in in vitro cultivation of lymphocytes, lymphoma cells and some other cells including human carcinomas are profoundly improved by 2-mercaptoethanol . These cells hardly take up cystine, an essential nutrient in the culture medium, but in the presence of 2-mercaptoethanol they can utilize cystine . Recently it has been found that 2-mercaptoethanol is effective in the in vitro cultivation of pathogenic trypanosomes and in the in vitro development of bovine embryos . The mechanisms by which 2-mercaptoethanol improves the survival and growth of these cells are described. Res Vet Sci, 1992 Sep, 53(2), 267 - 8 Culture of sheep Chlamydia in a sheep fibroblast cell culture; Philips HL et al.; Abortion and enteric isolates of Chlamydia psittaci from sheep differed in their growth in a fibroblastic cell culture derived from the small intestine of a lamb . Twenty abortion isolates, each from a different farm, produced large inclusions which could be passaged several times whereas 10 enteric isolates each from different farms (but from some of the farms of origin of the abortion isolates) produced sparse inclusions which could not be passaged . This appears to be a rapid method of distinguishing abortion and enteric isolates and may indicate different nutritional requirements or be related to the invasiveness of the isolates. J Pharm Sci, 1992 Sep, 81(9), 879 - 87 Epithelial transport of drugs in cell culture . VII: Effects of pharmaceutical surfactant excipients and bile acids on transepithelial permeability in monolayers of human intestinal epithelial (Caco-2) cells; Anderberg EK et al.; The effects of anionic (sodium dodecyl sulfate and sodium dioctyl sufosuccinate) and nonionic (polysorbate 80 and polyoxyl 40 hydrogenated castor oil) synthetic surfactants and bile acids (sodium taurocholate, sodium taurodeoxycholate, and sodium taurodihydrofusidate) on epithelial integrity were studied in monolayers of human intestinal epithelial (Caco-2) cells grown on microporous polycarbonate filters . The effects of the surfactants on intracellular enzyme activity, cell monolayer permeability, and morphology were studied . The effects on permeability were studied by two methods: measurements of transport of marker molecules (mannitol and polyethylene glycol) and measurements of transepithelial electrical resistance . All surfactants demonstrated concentration-dependent effects on intracellular enzyme activities, permeability, and morphology . The effects of the anionic surfactants were more pronounced than those of the nonionic surfactants . The effects on transepithelial electrical resistance correlated with intracellular dehydrogenase activity . Fluxes of marker molecules were the most sensitive measure of epithelial integrity . The results indicate that the hydrophilic marker molecules permeate the epithelial monolayers through different pathways at different concentrations of the surfactants . The effects of the surfactants were reversible at intermediate concentrations, even though the morphology of the monolayers had changed . The results agree with published data obtained with experimental animals and indicate that Caco-2 cells can be used to study the concentration-dependent effects of surfactants and other pharmaceutical additives on intestinal epithelial permeability. J Endocrinol Invest, 1992 Sep, 15(8), 567 - 72 Use of granulosa-luteal cell culture to evaluate low and high clinical responses to menotropin stimulation; Hurst BS et al.; The cause of a poor response to human menopausal gonadotropin (hMG) remains unexplained . To determine whether aromatase activity of cultured granulosa cells obtained from relatively low estradiol (E2) responders (serum E2 < 1000 pg/ml) to hMG therapy differed from that of good responders (E2 > or = 1000 pg/ml), we prospectively compared serum E2 on the day of human chorionic gonadotropin administration to in vitro aromatase activity following a 72-h culture . Granulosa cells were obtained from seven women undergoing hMG therapy and oocyte aspiration . Follicle stimulating hormone (FSH) was added to one-half of the cultures . Serum E2 was determined by radioimmunoassay, and aromatase activity was determined indirectly by measuring tritiated water formed by aromatization of 1-beta {3H} androstenedione to estrogen in 1 h . In this study, luteinized granulosa cells from patients with a relatively low serum E2 produced less estrogen in cultures when compared to cells from higher responders (p < 0.01) . Aromatase activity was not significantly increased by FSH in the relatively high responders, whereas FSH stimulated a significant increase in aromatase activity in cells from lower responders (p < 0.001) . Our results indicate that the clinical response to hMG is at least partly due to the "quality" of granulosa cell aromatase activity . A clinically relevant "block" to FSH action may be present in vivo in low responders which can be reversed in culture by addition of FSH. Neuroscience, 1992 Sep, 50(1), 85 - 97 Epidermal growth factor affects both glia and cholinergic neurons in septal cell cultures; Kenigsberg RL et al.; The effects of epidermal growth factor on high density primary cultures of fetal (embryonic day 17) rat septal cells were examined . Under serum-free conditions, the continuous exposure of these cultures to epidermal growth factor for seven days significantly decreased choline acetyltransferase (EC 2.3.1.6) activity in a dose-dependent manner . Maximal decreases were observed from 1 to 10 ng/ml epidermal growth factor . This effect was completely abolished by the addition of anti-epidermal growth factor antibodies . The epidermal growth factor-mediated decrease in choline acetyltransferase activity was culture-time dependent, being first detectable after five days of factor application and may likely represent an inhibition of the spontaneous increase in enzyme activity that occurs with time in culture . Concomitant with changes in enzyme activity, epidermal growth factor produced a significant and proportional decrease in the number of acetylcholinesterase-positive neurons . This decrease in acetylcholinesterase-positive cells did not reflect a decrease in cholinergic cell survival as nerve growth factor could restore the number of acetylcholinesterase-positive neurons in epidermal growth factor-treated cultures to control levels . Furthermore, in these high-density cultures, epidermal growth factor did not affect general neuronal survival, while it did produce an increase in the number and intensity of glial fibrillary acidic protein-immunoreactive astroglia as well as in the number of macrophage-like cells . The proliferative response of these non-neuronal cells to epidermal growth factor, as assessed by {3H}thymidine incorporation, was evident after three days of epidermal growth factor application, persisted thereafter, and could be antagonized by the inclusion of the antimitotic 5-fluorodeoxyuridine . Furthermore, 5-fluorodeoxyuridine completely blocked the epidermal growth factor-mediated decrease in choline acetyltransferase activity . However, when epidermal growth factor was tested in pure glial cultures, it only directly induced proliferation of astrocytes . These results suggest that the proliferative response of either one or both of these glial cell types in the mixed cultures may be indirectly affecting cholinergic cell expression. Mutat Res, 1992 Sep, 275(3-6), 405 - 14 Cell culture models for oxidative stress: superoxide and hydrogen peroxide versus normobaric hyperoxia; Gille JJ et al.; According to the free radical theory of aging, loss of cellular function during aging is a consequence of accumulating subcellular damage inflicted by activated oxygen species . In cells, the deleterious effects of activated oxygen species may become manifest when the balance between radical formation and destruction (removal) is disturbed creating a situation denoted as 'oxidative stress' . Cell culture systems are especially useful to study the effects of oxidative stress, in terms of both toxicity and cellular adaptive responses . A better understanding of such processes may be pertinent to fully comprehend the cellular aging process . This article reviews three model systems for oxidative stress: extracellular sources of O2- . and H2O2, and normobaric hyperoxia (elevated ambient oxygen) . Methodological and practical aspects of these exposure models are discussed, as well as their prominent effects as observed in cultures of Chinese hamster cell lines . Since chronic exposure models are to be preferred, it is argued that normobaric hyperoxia is a particularly relevant oxidative stress model for in vitro cellular aging studies. Antiviral Res, 1992 Sep, 19(3), 219 - 32 The activity of (S)-1-{(3-hydroxy-2-phosphonyl methoxy) propyl} cytosine (HPMPC) against equine herpesvirus-1 (EHV-1) in cell cultures, mice and horses; Gibson JS et al.; The activity of the nucleotide analogue, (S)-1-{(3-hydroxy-2-phosphonyl methoxy) propyl} cytosine (HPMPC), against equine herpesvirus-1 (EHV-1) was tested in cell culture, mice and foals . The ED50 for plaque reduction was found to be 0.07 and 0.03 microgram/ml in RK-13 and EEL cells respectively . In mice, a single administration of HPMPC (20 mg/kg, s.c.) was very effective at reducing clinical signs and virus replication if given on the day before intranasal inoculation with EHV-1 . Treatment on the day of infection or day 1 p.i . was less effective, but still significantly reduced clinical signs and virus titres in the target organs (lungs and nasal tissue) . Furthermore, HPMPC was found to protect mice partially from an intracerebral inoculation with EHV-1 . Experiments in the horse suggested that HPMPC was also very active against EHV-1 in the natural host . Thus a single administration of HPMPC at 20 mg/kg, s.c., on the day of infection, markedly reduced clinical signs and nasal excretion of virus following intranasal inoculation with EHV-1 . HPMPC given as a divided dose of 1 mg/kg on day 0 and day 3 p.i . had no effect on clinical signs but did reduce nasal excretion of virus . The significance of these results is discussed. Biol Reprod, 1992 Sep, 47(3), 397 - 407 Gap junctions in myometrial cell cultures: evidence for modulation by cyclic adenosine 3':5'-monophosphate; Dookwah HD et al.; Primary cultures of myometrial cells from juvenile rats, continuous cultures maintained by serial passage, and a pSV3neotransfected myometrial cell line were established and utilized for the study of development and modulation of gap junctional intercellular communication (GJIC) in vitro . The smooth muscle origin and homogeneity of the cultures were verified by immunofluorescence staining of alpha-smooth muscle actin and cellular desmin . Although gap junctions were not detected in thin sections of juvenile and adult myometrial tissues by transmission electron microscopy, they were detected in cultured myometrial cells derived from juvenile and adult animals . The presence of GJIC in cultured cells was confirmed using a fluorescence recovery after photo-bleaching assay . Administration of exogenous estradiol-17 beta (10(-7) M) resulted in an increase in GJIC in primary and passage 9 myometrial cultures, whereas pSV3neo-transfected myometrial cells were not significantly different from untreated controls . The lack of estrogen responsiveness in pSV3neo-transfected cultures correlated with lower levels of estrogen receptors than in primary cultures . Addition of 1 mM 8-bromo-cAMP resulted in rapid (within 2 min) increases in dye transfer in both control and estradiol-17 beta-primed primary cultures . Uncoupling of cells by treatment with 1 mM 1-octanol, followed by addition of 1 mM 8-bromo-cAMP, resulted in increased GJIC in control and estradiol-17 beta-primed cultures, although up-regulation of GJIC in estradiol-17 beta-primed cultures was much greater than in control cultures . Comparative experiments carried out on a spontaneously immortalized rat granulosa cell line (SIGC), which expresses the same connexin43 species as myometrial cells, exhibited similar responses to exogenous 8-bromo-cAMP following uncoupling of gap junctions with octanol . While the results of these investigations may not be extrapolated to myometrium in vivo, they suggest that myometrial cell culture may offer additional opportunities to explore the temporal expression and modulation of GJIC in myometrium. Brain Res, 1992 Aug 21, 588(2), 191 - 200 Angiotensinogen is secreted by pure rat neuronal cell cultures; Thomas WG et al.; Previous studies are divided between those which support a neuroglial (astrocyte) source for brain angiotensinogen and those which indicate that both astrocytes and neurones synthesize the precursor of angiotensin II . In this study, separate cultures of astrocytes and neuronal cells were prepared and established as being essentially pure by appropriate immunocytochemical cell markers . Angiotensinogen production by these cultures, as measured by a direct radioimmunoassay, was 20.74 +/- 3.62 ng angiotensinogen/10(6) cells/24 h (mean +/- S.D., n = 8) for astrocytes and 4.39 +/- 0.94 ng/10(6) cells/24 h (mean +/- S.D., n = 29) for neurones . Angiotensinogen secretion from both cell types was unaffected by treatments which stimulate the regulatory secretory pathway by modulating intracellular cAMP levels . In contrast, it was reduced from 23.20 +/- 2.14 to 8.14 +/- 1.31 ng/10(6) cells/24 h (S.E.M., n = 7) in astrocyte cultures by the constitutive pathway inhibitor, monensin . Angiotensinogen secreted by astrocytes and neurones was compared to pure angiotensinogen and that in plasma and cerebrospinal fluid (CSF) by cation-exchange mono S column chromatography . Pure angiotensinogen eluted as two separate peaks corresponding to the major forms of plasma angiotensinogen, whereas angiotensinogen in CSF and culture media coeluted with a third minor form of plasma angiotensinogen . It was concluded that neuronal cells as well as astrocytes secrete angiotensinogen which is distinctly different from plasma angiotensinogen. FEBS Lett, 1992 Aug 17, 308(2), 161 - 4 Characterisation of a human bilirubin UDP-glucuronosyltransferase stably expressed in hamster lung fibroblast cell cultures; Sutherland L et al.; A cDNA encoding a human bilirubin UDP-glucuronosyltransferase has been isolated and stably expressed in Chinese hamster V79 lung fibroblast cell line . Western blotting of cell homogenates with anti-UGT antibody revealed a highly expressed protein of approx . 55.5 kDa in size . The expressed enzyme specifically catalysed the formation of bilirubin mono- and diglucuronides, and also catalysed the glucuronidation of two phenolic compounds, which are good substrates for other human UGT isoenzymes, at low rates. Neurosci Lett, 1992 Aug 17, 142(2), 196 - 9 Modifications of ependymal cells membranes by galactocerebrosides in cell culture; Laabich A et al.; In this paper we have demonstrated that treatment of ependymal cells in culture by galactocerebrosides induced a decrease in plasma membrane fluidity and an increase of EGF binding sites . We have shown in a previous work that galactocerebroside in vitro and in vivo caused an important morphological change in ependymal cells that grew into an astrocytic shape after a five day treatment . We discuss the hypothesis that the first event in morphological effect could be a modification of plasma membrane followed by important changes in molecules distribution. J Chromatogr, 1992 Aug 7, 579(1), 158 - 64 Improved high-performance liquid chromatographic method for the determination of ethylmorphine and its metabolites in microsomal incubations and cell culture media; van't Klooster GA et al.; Ethylmorphine N-demethylation is used as a marker pathway in studies of rat cytochrome P450 3A and 2C11 biotransformations . At present, microsomal activities are generally measured by a colorimetric determination of the formed formaldehyde . In the present study, a high-performance liquid chromatographic method of separating and quantifying both the N-demethylated (norethylmorphine) and the O-de-ethylated (morphine) metabolites is described . Either samples are extracted with ethyl acetate or proteins are precipitated with zinc sulphate-barium hydroxide . Separation is achieved on a CN reversed-phase column, using a mobile phase of phosphate buffer (pH 4.5)-acetonitrile (90:10, v/v) . At a flow-rate of 1.5 ml/min, the analysis time is 30 min . The limit of detection (ultraviolet, 210 nm) for ethylmorphine and its metabolites is 0.5 micrograms/ml. Eur J Pharmacol, 1992 Aug 3, 226(4), 373 - 6 The neuroprotective properties of ifenprodil, a novel NMDA receptor antagonist, in neuronal cell culture toxicity studies; Graham D et al.; We investigated the effect of ifenprodil on excitotoxic cell death induced by acute exposure to glutamate receptor agonists in primary cultures of foetal mouse cerebral cortex . L-Glutamate and N-methyl-D-aspartate (NMDA) but not kainate and quisqualate-induced toxicity was attenuated in the presence of ifenprodil . In addition, ifenprodil and MK-801 blocked NaCN-induced toxicity . It is concluded that the cerebro-protective properties of ifenprodil in these models are mediated by NMDA receptor antagonism. Anticancer Drug Des, 1992 Aug, 7(4), 297 - 303 Photodynamic effects of a cationic mesosubstituted porphyrin in cell cultures; Villanueva A et al.; The photobiological activity of mesotetra (4N-methylpyridyl) porphine (T4MPyP) has