bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spontaneous Production of a C‐Type RNA Virus in a Cell Line Derived from Rat Glioma
Authors: Igarashi Koichi , Sasada Reiko , Niiyama Yasuhiko , Kozai Yoshio , Sugino Yukio 
Published: November 2013

AbstractThe spontaneous production of a rat C‐type RNA virus (ACV) in a cultured cell line (AC cells) established from a chemically induced rat glioma was studied. The characteristics of ACV were: morphology typical of C‐type RNA virus; buoyant density of 1.15 g/ml in a sucrose density gradient; RNA directed DNA polymerase activity; viral core with a density of 1.28 to 1.30 g/ml; 70S RNA with dimer structure; and structural protein composed of mainly four polypeptides. Kinetical analysis of DNA‐DNA hybridization revealed that DNA sequences homologous to DNA transcripts of RNA of ACV were present in rat cells. RNA directed DNA polymerase of ACV partially cross‐reacted with antiserum to the polymerase of Rauscher murine leukemia virus. These data suggest that ACV is an endogenous C‐type RNA virus of rat origin.
Physico‐ and Immunochemical Properties of Staphylococcal Protein A Extracellularly Produced by a Set of Mutants from Staphylococcus aureus Cowan I
Authors: Movitz Jan , Masuda Shogo , Sjöquist John 
Published: November 2013

AbstractMutant strains of Staphylococcus aureus have been isolated using a simple cosedimentation technique. While the parental strain contains predominantly a cell‐bound protein A, the mutant strains exclusively produce extracellular protein A. The mutant forms of protein A all have lower molecular weights than that of protein A from the parental strain. They showed the same antigenicity as the parental protein A and gave similar reactivity with immunoglobulin to the parental one except for one mutant. A conspicuous spur was observed between the parental protein A and that produced by the mutant against normal dog serum in the micro‐Ouchterlony immunodiffusion test.
Pathogenesis of Hobbs' Heat‐Sensitive Spore Forming Clostridium perfringens Type A Strain†
Authors: Chakrabarty A.K. , Narayan K.G. 
Published: November 2013

AbstractFood poisoning in man due to heat‐sensitive strains of Cl. perfringens type A appeared to be mediated through enterotoxin synthesized in vivo during sporulation. A minimum of 2.0 × 105 vegetative cells suspended in sporulation medium was sufficient to elicit gut‐loop response in rabbits. The functional disturbance in the gut as well as the structural changes were progressive and proportional to the size of the inoculum up to a dose limit of 2.0 × 107 vegetative cells and beyond this the changes remained steady.
Detection of Human B Cells and Chronic Myelocytic Leukemic Cells by Rosette Formation with Sheep Erythrocytes and Fresh Human Sera
Authors: Chen Po‐Min , Yamanaka Noboru , Kikuchi Kokichi , Kitajima Koichi , Kimura Ikuro 
Published: November 2013

AbstractA new method of detecting the C3b receptor is reported. A particular merit of this method is that anti‐RBC rabbit antiserum is not required. Rosettes were formed with human B lymphocytes, B lymphoblasts and granulocytes, using sheep erythrocytes (SRBC) sensitized with fresh human serum (FHS). T lymphocytes and T lymphoblasts did not form rosettes. The percentage of cells forming rosettes with this method approximated the percentage of rosettes formed with EACm. However, FHS coated SRBC did not react with most cells of B cell type chronic lymphocytic leukemia (CLL), whereas EACm rosette formations showed a definite reaction. On the other hand, 34–58% of cells of chronic myelocytic leukemia (CML) bound with the indicator red cells. SRBC sensitized with fresh rabbit or guinea pig serum formed rosettes with PBL, tonsil cells, B lymphoblasts and granulocytes. Complement and IgM antibody were required for this reaction, as in EAC rosette formation.
The Induction of Interferon by Vesicular Stomatitis Virus in Mouse L Cells
Authors: Nishiyama Yukihiro , Ito Yasuhiko , Shimokata Kaoru , Kimura Yoshinobu 
Published: November 2013

AbstractAlthough no detectable interferon was produced when L cells were infected with wild‐type VSV (VSV‐o), considerable amounts of interferon were produced when cells were infected with UV‐irradiated VSV‐o at a multiplicity equivalent to 10 PFU/cell. Treatment of VSV‐o with UV‐light resulted in the marked reduction of the RNA synthesizing capacity and cytotoxity of the virus, and the UV‐irradiated virus had neither infectivity nor interfering activity against homologous viruses. The amount of interferon induced by UV‐VSV‐o was markedly influenced by multiplicity of infection and incubation temperature. Less‐virulent temperature‐sensitive mutants (VSV‐mp and VSV‐sp) derived from L cells persistently infected with VSV induced interferon in L cells without treatment of the viruses with UV‐light, but these viruses could not induce interferon if the infected cells were incubated at nonpermissive temperature, or if cells were infected at multiplicities of more than 10 PFU/cell. On the other hand, it was shown that treatment of cells with cycloheximide (100 μg/ml) delayed the expression of cell damage caused by non‐irradiated VSV‐o and resulted in the production of interferon when cycloheximide was removed from the cultures. These results indicate that VSV has intrinsically interferon‐inducing capacity in L cells and can induce interferon if the induction is carried out under such condition that cell damage caused by VSV are suppressed or delayed. Furthermore, the effect of pretreatment of cells by interferon and undiluted passage of VSV‐o on interferon induction was discussed in relation to persistent infection.
Different Effects of the Capsular Polysaccharide of Klebsiella pneumoniae on the Functions of Various Subpopulations of B Cells in the Immune Response of Mice to T‐Dependent Antigen
Authors: Nakashima Izumi , Yokochi Takashi , Nagase Fumihiko , Kato Nobuo 
Published: November 2013

AbstractUsing the capsular polysaccharide of Klebsiella pneumoniae (CPS‐K) as a polyclonal B‐cell activator (PBA) and sheep red blood cells (SRBC) as a T‐dependent antigen, we studied the effects of PBA on the functions of various subpopulations of B cells in the immune response of mice to T‐dependent antigen. Antibody‐forming cells (AFC) of IgM and IgG types were estimated as anti‐SRBC direct and indirect plaque‐forming cells (PFC), and the B cells with precursor activities involving generation of AFC and supplementing new B cells as rosette‐forming cells (RFC) of the B‐cell type. Stimulation of normal mice by CPS‐K caused a definite increase in the number of direct PFC but not in that of indirect PFC and RFC in the spleens. The responsiveness of spleen cells of CPS‐K‐treated mice to generate PFC and RFC responses to a subsequent injection of SRBC was lower than that of CPS‐K‐untreated normal mice. In this case, the responsiveness to generate RFC and indirect PFC was inhibited more strongly by CPS‐K than that to generate direct PFC. When CPS‐K was injected into normal mice simultaneously with SRBC, CPS‐K never decreased but increased the levels of PFC and RFC responses to SRBC. In the spleens of SRBC‐primed mice, the number of RFC was markedly decreased following injection of CPS‐K, the number of direct PFC was increased only slightly and the number of indirect PFC was increased very slightly. The responsiveness of spleen cells of these CPS‐K‐treated SRBC‐primed mice to generate secondary PFC and RFC responses to a subsequent injection of SRBC was much lower than that of CPS‐K‐untreated SRBC‐primed mice. In this case, the responsiveness to generate the secondary RFC and indirect PFC responses was more strongly inhibited by CPS‐K than that to generate the secondary direct PFC response. When CPS‐K was injected into SRBC‐primed mice simultaneously with the secondary injection of SRBC, there were marked decreases in the level of the secondary RFC response and slight decreases in that of the secondary indirect PFC response, but little change in that of the secondary direct PFC response. From these results it has been concluded that CPS‐K provides the positive signal (the minor action) and the negative signal (the major action) to various subpopulations of B cells functioning at various stages of the immune response to T‐dependent antigen in different ways, and acts to regulate the levels of B‐cell responses to the antigen‐mediated positive signal.
Dysfunction of Thymocytes of C3H/HeJ Mice in Blastogenic Response to Anti‐Thymocyte Serum In Vitro and Its Repair with Lipopolysaccharide Induced Mediator
Authors: Tanabe Masao J. , Nakano Masayasu 
Published: November 2013

AbstractIn vitro mitogenic responses of thymocytes to rabbit anti‐mouse thymocyte serum (ATS) have been compared in several mouse strains. The response of thymocytes of C3H/HeJ mice is about one‐third of those of thymocytes of C3H/He, ATL or ATH strains. Phenol‐extracted bacterial lipopolysaccharide (LPS) does not induce mitogenic response in cultured C3H/HeJ spleen cells, but the spleen cells of all other strains used are capable of responding to LPS. The low response of C3H/HeJ thymocytes to ATS is restored by adding “endotoxin soup” prepared from spleen cell cultures of LPS‐responder mice in the presence of LPS. Neither soup prepared from C3H/HeJ spleen cell cultures without the addition of LPS nor soup prepared from cell cultures with LPS show such restoration of the response of C3H/HeJ thymocytes to ATS. The molecular size of the active factor in “endotoxin soup” was estimated on a Sepharose CL‐4B column and determined to be about 20,000 daltons. The activity of “endotoxin soup” is destroyed by heating at 70 C for 30 min or 80 C for 10 min and diminished by digestion with trypsin. The mechanisms of restoration of low response of C3H/HeJ thymocytes to ATS by “endotoxin soup” are discussed.
Effect of Carbohydrates and Control of Culture pH on Beta Toxin Production by Clostridium perfringens Type C
Authors: Sakurai Jun , Duncan Charles L. 
Published: November 2013

AbstractClostridium perfringens type C strain CN 5384 produced a higher level of beta toxin in a controlled pH medium containing 1% glucose, starch, or sucrose than in media with dextrin, fructose, or raffinose. Toxin synthesis was not related to the growth yield.The effect of glucose on beta toxin production by 11 strains was investigated with and without control of the culture pH at 7.5. Strain CN 5386 produced distinctly higher toxin when the pH of the culture was maintained at 7.5, compared with uncontrolled pH.
Mode of Cell Separation and Arrangement of Staphylococcus
Authors: Amako Kazunobu , Umeda Akiko 
Published: November 2013

AbstractThe process of cell separation and arrangement of Staphylococcus was investigated using a scanning electron microscope.After two cycles of cell division, the Staphylococcal cells cultured on an agar medium were generally observed to be arranged in three morphological types: linear, square, and crooked arrangements. Results of the examination of cell surface structure revealed that separations had occurred in these clustered cells following two patterns. One type of second separation occurred parallel to the transversal axis of the preceding pair of the parental cells (X‐type) and the other occurred tangential to it (Y‐type). In the former type, the four daughter cells were usually arranged tetragonally after the separations, and in the latter type they were arranged either linearly or crookedly depending on the direction of the second separation. The final pattern of the cell arrangement was thus determined by the type of septal wall formation and the direction of cell separation. After several cycles of cell divisions, the cells were finally arranged in an irregular grape‐like cluster, even though the cross walls were formed regularly at the rectangular face of the preceding cross walls.
Effects of In Vivo Priming on In Vitro Induction of Cytotoxicity
Authors: Yamada Hiroyasu , Nomoto Kikuo , Takeya Kenji 
Published: November 2013

AbstractIn vivo presensitization of donor mice of responding cells with third party cellular antigens augmented in vitro generation of cytotoxic T lymphocytes in allogeneic and xenogeneic combinations. In vitro induction of detectable cytotoxicity in presensitized responding cells required the incubation period needed for in vitro primary response. However, such cytotoxic T lymphocytes were generated after in vitro stimulation with monolayers of methylcholanthrene‐induced tumor cells, UV‐irradiated or heated spleen cells which had proved to be effective in secondary but not in primary response. Presensitized responding cells exposed to 600R‐irradiation did not augment in vitro induction of cytotoxicity in normal responding cells. The augmenting effect of presensitized responding cells may be attributable to radiosensitive T cells which are in a transitional state in differentiation from typical unprimed cells to typical primed cells.
Interferon and Cytotoxic Factor (Cytotoxin) Released in the Blood of Mice Infected with Mycobacterium bovis BĆG
Authors: Kato Nobuo , Nakashima Izumi , Ohta Michio , Naito Setsuko , Kojima Takashi 
Published: November 2013

AbstractInterferon production stimulated by the active substance (neutral fraction) of the capsular polysaccharide of Klebsiella pneumoniae (neutral CPS‐K) in BCG‐infected mice was compared with that by bacterial lipopolysaccharide (LPS). Prior infection with BCG increased the responsiveness of mice to the lethal effect of neutral CPS‐K as well as to that of LPS. Associated with this, BCG‐infected mice showed a markedly enhanced ability to produce interferon after stimulation not only by LPS but also by neutral CPS‐K. In addition, a cytotoxic factor (cytotoxin) was found to be released in the serum of BCG‐infected mice after injection of these inducers. The kinetics of production of interferon and cytotoxin stimulated by neutral CPS‐K were very similar to those stimulated by LPS. The time pattern of cytotoxin production was not in parallel with that of interferon production. Interferon reached a peak 2 hr and cytotoxin 3 hr after injection with these inducers. Interferon and cytotoxin produced by neutral CPS‐K showed essentially the same stabilities to heating at 56 C and to treatment at pH 2 respectively as those produced by LPS. Interferon was inactivated by heating at 56 C more rapidly than cytotoxin. Cytotoxin was inactivated by treatment at pH 2 for 24 hr, whereas interferon activity was well preserved after this treatment. These results suggest that both activities are the result of different substances.
Further Studies on Generation of Macrophages in In Vitro Cultures of Mouse Spleen Cells and Its Inhibition by the Capsular Polysaccharide of Klebsiella pneumoniae
Authors: Yokochi Takashi , Nakashima Izumi , Kato Nobuo 
Published: November 2013

AbstractAlthough the number of macrophages detected in cultures of mouse spleen cells at the start of the culture was very small, it markedly increased during further incubation. Macrophages were generated not only from the glass‐adherent cell fraction of spleen cells, but also from the nonadherent cell fraction obtained after removal of adherent cells either by incubating in glass petri dishes or by passing through a glass bead column. The generation of macrophages from the nonadherent cell fraction occurred even when it was separated as late as 48 hr after the start of the culture. The phagocytic activity of macrophages newly generated from the nonadherent cell fraction was relatively weak, but it was activated during further incubation. Based on these results, the maturation process of macrophages can be divided into at least the following four stages; glass‐nonadherent nonphagocytic precursor cells, glass‐adherent nonphagocytic precursor cells, immature macrophages with low phagocytic activity, and mature macrophages with full phagocytic activity. The addition of the capsular polysaccharide of Klebsiella pneumoniae (CPS‐K) to cultures of spleen cells markedly suppressed the generation of macrophages. The suppressive effect of CPS‐K depended on its dosage, and the minimum concentration of CPS‐K showing a definite effect was 0.05 μg/ml. CPS‐K inhibited further generation of macrophages in either the nonadherent or adherent cell fraction at any time after the start of the culture. The suppressive effect of CPS‐K on the generation of macrophages could not be reversed by simple washing of spleen cells which had been kept in contact with CPS‐K for 3 hr. There was no evidence which showed that CPS‐K exhibited direct cytotoxic effects on spleen cells in the culture.
Effect of Polysaccharides from Ganoderma applanatum on Immune Responses
Authors: Nakashima Shoichi , Umeda Yukio , Kanada Taira 
Published: November 2013

AbstractPrior intraperitoneal (i.p.) or oral administration of the polysaccharide preparation from a kind of mushroom, Ganoderma applanatum (Pers.) Pat. of Basidiomycetes, exerted an enhancing effect on the induction of delayed hypersensitivity (DH) to protein antigen as measured by the footpad reaction (FPR), and expanded the size of T cell memory for the IgG antibody response. One of the active principles was partially purified and found to be associated with a polysaccharide‐rich fraction. The induction of DH was enhanced by treatment with an appropriate dose of the mushroom extract, whereas increasing the dose resulted in almost complete loss of the enhancing activity.The mechanism for the enhancing effect of the mushroom extract on the induction of DH was explored by the adoptive cell transfer technique. Although an i.p. injection of methylated bacterial α‐amylase (M‐BαA) in incomplete Freund's adjuvant (IFA) has been found to generate in the spleen the antigen‐specific suppressor T cells capable of inhibiting the induction of DH 5 days after immunization, the same treatment of mice given prior injections of the mushroom extract did not raise the suppressor cell activity, but transfer of these spleen cells (6 × 107) into syngeneic recipient mice which had been primed with a subcutaneous (s.c.) injection of M‐BαA in complete Freund's adjuvant (CFA) resulted in substantial amplification of the expression of DH. The absence of effector T cells for DH in the transferred spleen cells was confirmed by the failure to transfer DH into cyclophosphamide (CY)‐treated mice with the amplifying cells. The amplifying activity was antigen‐nonspecific and mediated by cells sensitive to treatment with anti‐θ antiserum plus complement. Therefore, the nonspecific enhancing effect of the mushroom extract could not be explained by the possibility that pretreatment with the extract eliminated the antigen‐specific suppressor T cells. Other adoptive cell transfer experiments revealed that nylon wool‐passed cells from mice unprimed but treated with the mushroom extract were able to exert an enhancing activity on the expression of effector T cells in DH. The results indicate that the treatment with an appropriate dose of the extract enhances the induction of DH by activation of the nonspecific amplifier T cells.
Partial Purification of Guinea Pig MIF by Affinity Column Chromatography Using Macrophages
Authors: Onozaki Kikuo , Haga Sinji , Miura Kaoru , Hashimoto Tatsuichiro 
Published: November 2013

AbstractFirst we have confirmed the previous observation that the macrophage migration inhibitory factor (MIF) was adsorbed on normal peritoneal macrophages when they were incubated at 4 C for 60 min. It was found that macrophages fixed with 2% glutaraldehyde gave more reproducible results than viable cells in terms of “adsorption” of guinea pig MIF. The adsorption was achieved more completely at 37 C than at 4 C, indicating that this reaction is a temperature‐dependent phenomenon. Using these glutaraldehyde‐fixed macrophages, a kind of cell‐affinity column was successfully developed. The guinea pig MIF preparation lost its activity when it was passed through this affinity column, and MIF adsorbed on the column was recovered by elution with 0.1 M (L)‐fucose or 0.1 M (D)‐glucose. Such MIF active eluate was found to be at least 30–40 fold more pure than the original MIF preparation which had been previously fractionated according to its molecular weight. Therefore, this type of macrophage‐affinity column may be useful for the purification of MIF.
Interaction between 30 S Ribosomal Components in a Viomycin Resistant Mutant of Mycobacterium smegmatis
Authors: Mizuguchi Yasuo , Suga Kiyoko , Yamada Takeshi 
Published: November 2013

AbstractA high level viomycin resistant mutant of Mycobacterium smegmatis ATCC 14468 (AC16) was analyzed genetically and biochemically in an attempt to understand the mechanisms of expression of high level viomycin resistance and co‐resistance to kanamycin and streptomycin. Genetic analysis has shown that at least three different genes (vicC, str, and kan) were involved in the phenotypic expression of drug resistance in AC16, and high level resistance to viomycin was due to interactions between the products of these genes.
Effect of Nucleosides on Interferon Production and Development of Antiviral State Induced by Poly I·Poly C
Authors: Machida Haruhiko , Kuninaka Akira , Yoshino Hiroshi 
Published: November 2013

AbstractEffect of nucleosides both on induction of antiviral state in chick embryo cells (CEC) or rabbit kidney cells (RK13) and on interferon production in RK13 or mouse fibroblast cells (L cells) by polyriboinosinic‐polyribocytidylic acid (poly I·poly C) was studied. Addition of inosine or a fifty‐fifty mixture of inosine and uridine at a final concentration of 0.1 mM to 10 mM to a growth medium enhanced development of antiviral state in CEC. The nucleoside effect was also observed in RK13 at 0.1 mM but not at a concentration higher than 1 mM. Interferon production in RK13 by superinduction (sequential treatment with metabolic inhibitors after exposure to poly I·poly C) was enhanced 1.5‐ to 4.0‐fold by addition of the nucleoside mixture to the growth medium. When RK13 was pretreated with 10 units per ml of interferon and then superinduced by inhibitors, the enhancing effect of nucleosides on interferon production was not observed. Interferon production in L cells was potentiated a little by addition of 1 mM of the nucleoside mixture to the growth medium. The effect of nucleoside was not observed when the nucleosides were added after exposure to poly I·poly C. The nucleoside effect may be applicable for production of high titered interferon.
Effects of Tannic Acid and Its Related Compounds upon Chikungunya Virus
Authors: Konishi Eiji , Hotta Susumu 
Published: November 2013

AbstractThe present report describes not only the effects of tannic acid (TA; belonging to hydrolyzable tannins) and its related compounds upon the infectivity of Chikungunya virus (CHIKV) but also the mechanism involved in this phenomenon. Our data show that TA inactivates CHIKV in vitro. Since the inactivating effect turned out to be pH‐dependent and was suppressed by bovine serum albumin, it is most probable that the virus‐inactivating capacity of TA is attributable to its preferential binding to proteins of virus particles. Examination on the virus‐inactivating capacities of some TA‐related compounds and comparison of their structures indicated that the active site of TA and its analogues might be the phenolic hydroxyl groups in their molecules. It seems that the active groups interact with the proteins of virus particles, resulting in a reduction or loss of viral infectivity. Discussion is made on the specificity of the actions of tannins and the possibility of application thereof to chemicals which are useful to investigate the nature and properties of viral proteins.