bluuebunny/crossref_metadata_2025_split huggingface dataset:
Participation of NK1.1+ T Cells in the Rejection of lpr αβT Cells When Bone Marrow Cells of Ipr Mice Are Transplanted into B6 Mice
Authors: Tsukahara Akihiro , Kawamura Hiroki , Iiai Tsuneo , Moroda Tetsuya , Suzuki Susumu , Tada Takashi , Minagawa Masahiro , Musha Nobuyuki , Hatakeyama Katsuyoshi , Abo Toru 
Published: November 2013

AbstractWhen C57BL/6 (B6) mice were irradiated (9 Gy) and received bone marrow (BM) cells of B6‐lpr/lpr mouse origin (i.e., lpr→B6), all mice died within 6 days. In the irradiated B6 mice, radioresistant CD3− IL‐2Rβ+ NK cells and IL‐2Rβ CD3int cells (i.e., CD3int cells of extrathymic origin) remained, especially in the liver. There were two subsets, NK1.1+ and NK1.1−, among the IL‐2Rβ+ CD3int cells. However, the NK1.1+ subset (i.e., NK1.1+ T cells) was much more radioresistant, and the majority of CD3int cells belonged to this subset in irradiated mice. The expansion of lymphocytes from injected BM cells did not occur in the irradiated B6 mice. However, such expansion did take place in irradiated B6‐lpr/lpr mice injected with both BM cells of B6‐lpr/lpr and B6 origin. As a result, the mice subjected to BM cells survived. Irradiated B6 mice were treated in vivo with anti‐NK1.1 mAb or anti‐asialoGM1 antibody to eliminate NK cells alone or both NK cells and NK1.1+ T cells. When irradiated B6 mice were pretreated with anti‐NK1.1 mAb, the mice could survive. These results suggest that intact NK1.1+ T cells of extrathymic origin may recognize abnormal BM cells with the lpr gene and inhibit the expansion of lymphocytes, including abnormal double‐negative CD4−8− cells, in B6‐lpr/lpr mice. To inhibit the expansion of lymphocytes, mechanisms other than Fas ligand/Fas molecules on extrathymic T cells may be responsible.
Plasmid Maintenance Renders Bacteria More Susceptible to Heat Stress
Authors: Sato Takako , Kuramitsu Howard 
Published: November 2013

AbstractThe presence of shuttle plasmid pTS749 in the oral bacterium Streptococcus mutans resulted in growth inhibition under heat stress conditions. This effect was dependent upon the growth stage of the inoculum used to initiate growth. Likewise, the introduction of plasmids containing distinct ori sequences into Escherichia coli also resulted in growth inhibition at elevated temperatures and could be correlated with the plasmid levels within the cells. These results suggest that these plasmids in bacteria render the cells to be more susceptible to heat stress conditions.
Studies on Rabies Virus RNA Polymerase: 1. cDNA Cloning of the Catalytic Subunit (L Protein) of Avirulent HEP‐Flury Strain and Its Expression in Animal Cells
Authors: Morimoto Kinjiro , Akamine Takayuki , Takamatsu Fumihiko , Kawai Akihiko 
Published: November 2013

AbstractTo investigate the RNA polymerase of rabies virus, we cloned a cDNA of the catalytic subunit (called L protein because of its large molecular size) of the HEP‐Flury strain, an avirulent strain obtained by high frequencies of serial embryonated hen egg passages. Nucleotide sequencing showed that the cDNA encodes a long polypeptide of 2,127 amino acids (Mr. 242,938). A comparison of the deduced amino acid sequence with that of other strains (PV and SAD B19) indicated that the sequence was highly conserved, except for several amino acid substitutions which were accumulated in some limited regions. A fragment of the cDNA was used for expression in Escherichia coli (E. coli) to prepare the L antigen for raising the antibodies in rabbits. Immunoprecipitation studies with the rabbit antiserum showed that the polypeptides produced in the L cDNA‐transfected COS‐7 cells displayed almost the same electrophoretic mobility as that of authentic L protein. Immunofluorescence studies indicated that both L and P (another subunit of RNA polymerase) proteins displayed colocalized distribution with the nucleocapsid antigen (N) in the cytoplasmic inclusion bodies, where envelope proteins (G and M) were absent. On the other hand, expression of the L protein alone did not cause inclusion body‐like granular distribution, suggesting that the inclusion body‐like accumulation depends on certain interaction(s) with other viral gene products, probably with the ribonucleoproteins comprising the inclusion bodies.
Effect of IgA1 Protease on the Ability of Secretory IgA1 Antibodies to Inhibit the Adherence of Streptococcus mutans
Authors: Tyler Beth M. , Cole Michael F. 
Published: November 2013

AbstractSecretory IgA (SIgA) is the principal immunoglobulin isotype present in the mucosal secretions of humans. SIgA is thought to play a major role in host defense at these surfaces by inhibiting the colonization of potentially pathogenic microorganisms. A number of bacteria that are mucosal pathogens of humans produce a protease that specifically cleaves the IgA1 subclass of humans and great apes at the hinge region to produce Fab and Fc fragments. In order to study the effect of IgA1 protease on the ability of SIgA1 antibodies to inhibit bacterial adherence, an in vitro assay that quantifies the adsorption of radiolabeled Streptococcus mutans to hydroxyapatite (HA) beads was employed. High titer S. mutans‐specific SIgA1 and SIgA2 antibodies were induced in chimpanzee milk for use in the assay. Fabα1 fragments had significantly reduced ability to inhibit adherence of S. mutans to saliva‐coated HA compared to intact SIgA1 or SIgA2 anti‐S. mutans antibodies. These data support the potential importance of IgA1 proteases as an ecological determinant in the oral cavity and their role as a determinant of pathogenesis of pathogenic bacteria whose portal of entry is the mucosal surface.
Heterogeneity in Expression of Lipopolysaccharide and Major Outer‐Membrane Proteins by Strains of Escherichia coli O157 with Different H‐Serotypyes
Authors: Fujimoto Shuji , Meno Yuko , Horikawa Kazumi 
Published: November 2013

AbstractA total of 11 strains of Escherichia coli (E. coli) belonging to serogroup O157 were examined for the expression of long‐chain lipopolysaccharide (LPS) and major outer‐membrane proteins (OMPs) by means of SDS‐PAGE. The strains belonged to either one of four different flagellar (H) types or did not express flagella. Four of the eleven strains carried genes encoding Shiga‐like toxins (SLTs). All the strains exhibited one of four LPS profiles, designated A, B, C or D. Electron microscopic analysis with the freeze‐substitution technique demonstrated the differences in the cell surface structures of strains with each LPS profile. Strains with LPS profile A, B or C had layers of thin fibers 10, 20 and 20 nm long, respectively, on the outer membrane but strains with LPS profile D had no such structure. An analysis of the OMPs showed that all the strains had one of four OMP profiles, designated I, II, III or IV. Both LPS and OMP profiles were dependent on H‐serotypes, and the combination pattern of LPS and OMP profiles of the strains was unique for each H‐serotype. These data support the existence of heterogeneous groups of O157 strains.
Determination of Serotypes of Astroviruses by Reverse Transcription‐Polymerase Chain Reaction and Homologies of the Types by the Sequencing of Japanese Isolates
Authors: Matsui Mihoko , Ushijima Hiroshi , Hachiya Masahiko , Kakizawa Junko , Wen Leying , Oseto Mitsuaki , Morooka Keiichi , Kurtz John B. 
Published: November 2013

AbstractHuman standard astroviruses, serotypes 1 to 7, and 35 Japanese isolates were typed by reverse transcription and polymerase chain reaction (RT‐PCR) with serotype‐specific primers for the first time. The results were identical with those obtained by enzyme immunoassay with serotype‐specific polyclonal antibodies, a method which has already been reported. RT‐PCR with serotype‐specific primers is useful for epidemiological studies of astroviruses where serotype‐specific polyclonal antibodies are not available. Two parts of the capsid region, N terminus and C terminus, were sequenced. Serotypes differed in those regions. The N terminus differed less than the C terminus between serotypes. Both the N terminus and C terminus were similar intraserotypically with the exception of serotype‐4 isolates which could be divided into A and B subgroups on the basis of their C terminus sequences, which were not known previously.
The Functional Role of B7 Molecules on the Induction of Thymocyte Activation and Apoptosis
Authors: Aoki Naoko , Inobe Manabu , Murakami Masaaki , Abe Ryo , Lizuka Hajime 
Published: November 2013

AbstractTo evaluate the role of B7 on thymocyte activation and apoptosis, we took advantage of TCR transgenic mice in which the majority of thymocytes express a uniform TCR that is specific for ovalbumin. We also prepared Chinese hamster ovary (CHO) cells expressing B7 and appropriate class II molecules. We found that the apoptosis of double‐positive thymocytes by TCR‐mediated signaling, which presumably represents negative selection, requires a costimulatory signal provided by B7‐1 or B7‐2. The requirement of B7‐1 costimulation for the apoptosis of thymocytes does not change in either low or high antigenic peptide loading. We also demonstrated that two signals through TCR and CD28 augmented the proliferation of thymocytes, and the requirement of CD28‐mediated signal by B7‐1 or B7‐2 for thymocyte proliferation became less evident when high doses of antigenic peptide were loaded, indicating that the intensity of TCR‐mediated signal determines the requirement of B7‐mediated second signal for thymocyte proliferation.
Different Effects of Fibronectin on the Phagocytosis of Staphylococcus aureus and Coagulase‐Negative Staphylococci by Murine Peritoneal Macrophages
Authors: Shinji Hitomi , Sakurada Junji , Seki Keiko , Murai Miyo , Masuda Shogo 
Published: November 2013

AbstractFibronectin is known to be an important factor in colonization by Staphylococcus aureus of host tissues as well as other extracellular matrix proteins such as collagen and laminin. We investigated the effect of fibronectin on the phagocytosis of the S. aureus Cowan I strain by macrophages and of coagulase‐negative staphylococci (CNS) strains for comparison. Fibronectin‐reduced serum in place of normal serum lowered the phagocytic activity of the macrophages on the Cowan I strain. Purified fibronectin enhanced the phagocytic activity of the strain in a dose‐dependent manner. On the other hand, fibronectin did not show any opsonic effect on the ingestion of CNS strains, though the binding of fibronectin occurred equally well in CNS strains and the Cowan I strain. Fibronectin‐binding protein (FnBP), the specific fibronectin receptor on the surface on S. aureus, was detected in both the Cowan I strain and CNS strains. Polymerase chain reaction confirmed that not only the Cowan I strain, but also CNS strains possessed the FnBP gene. These results indicate that fibronectin shows an opsonic effect on the S. aureus, Cowan I strain but not on CNS strains, and suggest that the binding of fibronectin to FnBP is not sufficient for efficient phagocytosis of the staphylococci strains by macrophages.
Methods for Rapid Cloning and Detection for Sequencing of Cloned Inverse PCR‐Generated DNA Fragments Adjacent to Known Sequences in Bacterial Chromosomes
Authors: Pham Hong‐Son , Kiuchi Akio , Tabuchi Kiyoshi 
Published: November 2013

AbstractSince the invention of PCR, many adaptation techniques have been developed for sequencing DNA fragments flanking known sequences. Of them, inverse PCR is a matter of interest because of the simplicity of its principle. However, the protocols for inverse PCR introduced so far consist of some time‐consuming procedures, and with them, we cannot “walk” chromosomes too far since the number of suitable restriction enzymes is limited. Our experiments led to confirming simpler technical approaches applicable to the case of bacterial chromosomes, that is, designing two end‐specific “contextual” sequences with which we can quickly detect the desired clones of targeted DNA fragments by simply analyzing PCR products, employing “the minimum value of the desired fragments” as a “discriminating minimum” value to decrease contaminant DNA fragments, and creating a new tandem of two cleaved end fragments of a known sequence (“reordering”) for PCR amplification in combination with cloning of the inverse PCR‐generated DNA. With the improvements, we could both simplify the procedures and broaden the capacity of the inverse PCR in “walking” chromosomes.
Fimbria‐Mediated Coaggregation between Human Oral Anaerobes Treponema medium and Porphyromonas gingivalis
Authors: Umemoto Toshihiko , Yoshimura Fuminobu , Kureshiro Hidetoshi , Hayashi Jun‐Ichiro , Noguchi Toshihide , Ogawa Tomohiko 
Published: November 2013

AbstractBacterial binding phenomena among different bacterial genera or species play an important role in bacterial colonization in a mixed microbiota such as in the human oral cavity. The coaggregation reaction between two gram‐negative anaerobes, Treponema medium and Porphyromonas gingivalis, was characterized using fimbria‐deficient mutants of P. gingivalis and specific antisera against purified fimbriae and bacterial whole cells. T. medium ATCC 700273 strongly coaggregated with fimbriate P. gingivalis strains ATCC 33277 and 381, but not with afimbriate strains including transposon‐induced fimbria‐deficient mutants and KDP98 as a fimA‐disrupted mutant of P. gingivalis ATCC 33277. In the P. gingivalis‐T. medium coaggregation assay, the presence of rabbit antiserum against the purified fimbriae or the whole cells of P. gingivalis ATCC 33277 produced different “aggregates” consisting predominantly of P. gingivalis cells with few spirochetes, but both preimmune serum and the antiserum against the afimbriate KDP98 cells did not inhibit the coaggregation reaction. Heated P. gingivalis cells lost their ability to bind both heated and unheated T. medium cells. This T. medium‐P. gingivalis coaggregation reaction was inhibited by a cysteine proteinase inhibitor, leupeptin, and also by arginine and lysine, but not by EDTA or sugars including lactose. A binding assay on nitrocellulose membranes and immunoelectron microscopy demonstrated that a heat‐stable 37 kDa surface protein on the T. medium cell attached to the P. gingivalis fimbriae.
Sequence Analysis of the Gene Encoding the Major Outer Membrane Protein rOmp B of Rickettsia japonica
Authors: Uchiyama Tsuneo 
Published: November 2013

AbstractThe complete nucleotide sequence of the gene encoding rOmp B (ompB), one of the two major outer membrane antigen proteins, of Rickettsia japonica was determined and compared to those of the other spotted fever group and typhus group rickettsiae. Open reading frame of the ompB gene of R. japonica consisted of 4,968 nucleotides coding for a putative precursor protein with 1,656 amino acids (aa) in which the N‐terminal 1,363 aa and the C‐terminal 293 aa encode 135‐kilodalton rOmp B and 32‐kilodalton β‐peptide, respectively. Putative promoter and terminator sequences for transcription were present in the upstream region of the ATG start codon and downstream of the TAA stop codon. Overall sequences of the ompB genes were well conserved beyond the group, especially in the β‐peptide regions.
Stable Marker on Flagellin Gene Sequences Related to Arabinose Non‐Assimilating Pathogenic Burkholderia pseudomallei
Authors: Wajanarogana Sumet , Sonthayanon Piengchan , Wuthiekanun Vanaporn , Panyim Sakol , Simpson Andrew J.H. , Tungpradabkul Sumalee 
Published: November 2013

AbstractUsing PCR‐based isolation and sequence analysis of the flagellin gene from two distinct biotypes of Burkholderia pseudomallei, a 15‐bp deletion was found within the variable domain of the gene in isolates capable of assimilating arabinose (Ara+). This finding led to the development of a PCR‐based method in order to differentiate and identify pathogenic B. pseudomallei for epidemiological study. A pair of specific primers was designed covering the 15‐bp deletion region at the variable domain. PCR‐amplification products of 176 and 191 bp in size were detected from 41 Ara+ isolates and 39 Ara— isolates of B. pseudomallei, respectively. Moreover, flagellin gene fragments of other bacterial species tested in this study were not amplified using these primers. The results suggest that the flagellin gene sequences of both B. pseudomallei biotypes in this region are stable and distinct. This method can be applied and useful for the epidemiological study of B. pseudomallei.
Cloning and Sequencing of the Central Region of the Flagellin Gene from the Gram‐Positive Bacterium Clostridium tyrobutyricum ATCC 25755
Authors: Arnold Françoise , Bédouet Laurent , Batina Pierre , Robreau Georges 
Published: November 2013

AbstractThe purpose of this study was to sequence the central part of the coding region of the Clostridium tyrobutyricum flagellin gene to improve the immunoenzymatic counting of cells after milk filtration. The coding region was amplified by PCR, and the amplified products were cloned. A DNA sequence analysis of positive clones gave us 1,131 nucleotides with a partial calculated flagellin molecular mass of 40,143 Da. The flagellar filament protein sequence exhibited high levels of homology to sequences of flagellin protein from other bacteria in both N‐ and C‐terminal parts, but little homology in the central domain. A PCR‐restriction fragment length polymorphism analysis of amplified C. tyrobutyricum flagellin gene products confirmed the variability of the central domain. The flagellin mRNA was determined to be 1.1 kb in size, which suggests a monocistronic mRNA. Furthermore, the deduced protein flagellin contains eleven potential N‐glycosylation sites and one sequence rich in serine, which could be modified by O‐glycosylation.
Experimental Murine Model for Autoimmune Enterocolitis Using Klebsiella pneumoniae O3 Lipopolysaccharide as a Potent Immunological Adjuvant
Authors: Paeng Noriko , Morikawa Akiko , Kato Yutaka , Sugiyama Tsuyoshi , Koide Naoki , Yoshida Tomoaki , Yokochi Takashi 
Published: November 2013

AbstractAn experimental model for autoimmune enterocolitis was produced in mice by repeated immunization of homologous colon extract together with Klebsiella O3 lipopolysaccharide (KO3 LPS) as an immunological adjuvant. Histological changes in the intestinal lesions were characterized by infiltration with polymorphonuclear leukocytes in the lamina propria, muscularis mucosae and submucosa of repeatedly immunized mice. No such intestinal lesions were produced in mice receiving injections of colon extract alone or KO3 LPS alone. Development of the autoantibody and delayed‐type hypersensitivity against colon extract were found in mice immunized with the mixture of colon extract and KO3 LPS. Distinct positive staining was detected specifically on the columnar epithelium of villi. Sera from hyperimmunized mice defined organ‐specific antigens present in the intestine. Therefore, it was suggested that the intestinal lesions might be caused by an autoimmune mechanism.
Antisense Macrophage Migration Inhibitory Factor (MIF) Prevents Anti‐IgM Mediated Growth Arrest and Apoptosis of a Murine B Cell Line by Regulating Cell Cycle Progression
Authors: Takahashi Akio , Iwabuchi Kazuya , Suzuki Masaki , Ogasawara Kazumasa , Nishihira Jun , Onoé Kazunori 
Published: November 2013

AbstractMacrophage migration inhibitory factor (MIF) is involved in the generation of cell‐mediated immune responses. Recently it has been reported that MIF also plays a role in cell proliferation and differentiation. In the present study, using a B‐cell line, WEHI‐231, and its stable MIF‐antisense transfectant, WaM2, as a representative transfectant, we investigated the mechanism underlying regulation of the cell growth by MIF. WaM2 cells produced less MIF than vector control or parental WEHI‐231 cells. Reduced and increased proportions were seen in G1 and S‐phase cells, respectively, in WaM2 as compared with WEHI‐231. Growth arrest and apoptosis after stimulation via surface Ig (sIg) were less prominent in WaM2 cells than those in WEHI‐231. However, the addition of recombinant rat MIF did not reverse the inhibition of the growth arrest and apoptosis induced in WaM2 by cross‐linking sIg. Almost the same amount of p27kipI expression was detected in WaM2 cells as those in WEHI‐231 and vector control cells. Cross‐linking of sIg elevated the p27kipI level equally in these cells irrespective of the MIF‐antisense expression. Taken together, it seems that MIF plays a role in inducing apoptosis in B cells upon IgM cross‐linking by regulating the cell cycle via a novel intracellular pathway.
Prolonged Incubation Period of Salmonellosis in an Outbreak of Salmonella enteritidis Infection
Authors: Nagai Kazushige , Mori Toshihiko , Tsuda Shinichiro , Izumiya Hidemasa , Terajima Jun , Watanabe Haruo 
Published: November 2013

AbstractAn outbreak of Salmonella enteritidis infections occurred in Otaru, Japan, in September 1997. A total of 143 cases of salmonellosis were reported to the local Public Health Center. In this outbreak, one case had a 214‐hr incubation period. We investigated 5 isolates including this case by phage typing and pulsedfield gel electrophoresis (PFGE) to determine the genetic heterogeneity of S. enteritidis. Five isolates were phage typed as reacted, but did not conform (RDNC) with identical reaction patterns and had quite similar PFGE patterns. Thus, the prolonged incubation period may not be attributed to genetic heterogeneity of the organism but rather to other factors.
Difference in Response of NK Cell Activity in Newborns and Adults to IL‐2, IL‐12 and IL‐15
Authors: Hoshina Takayuki , Kida Kazunori , Ito Masahiro 
Published: November 2013

AbstractThe killing activity of cord blood mononuclear cells (cMNC) against cytomegalovirus (CMV)‐uninfected and ‐infected fibroblasts was comparable to that of adult peripheral blood mononuclear cells (aPBMC). The killing activity of cMNC against K562 cells was significantly lower compared with that of aPBMC. Treatment of cMNC and aPBMC with interleukin‐2 (IL‐2), IL‐12 or IL‐15 significantly enhanced killing activity against K562 cells and CMV‐uninfected and ‐infected cells. By comparison of cMNC with aPBMC, killing activity against the K562 cells of cMNC was augmented to the level of aPBMC when cultured with IL‐2, IL‐12 or IL‐15. The killing activity of cMNC against CMV‐uninfected and ‐infected fibroblasts did not increase to the level of adult PBMC by treatment with IL‐2, IL‐12 or IL‐15. These data suggest that cord blood contains a functionally different NK cell subpopulation than that among adult NK cells.
Genotypic and Phenotypic Analysis of Bromovirus Adaptive Mutants Derived from a Single Plant
Authors: Fujita Yasunari , Mise Kazuyuki , Furusawa Iwao 
Published: November 2013

AbstractEight adaptive mutant clones have been made from the total RNA extracted from uninoculated upper leaves of a single cowpea plant exhibiting systemic infection after inoculation with a hybrid cowpea chlorotic mottle bromovirus (CCMV) with the 3a movement protein gene of CCMV replaced by that of cowpea‐nonadapted brome mosaic bromovirus (BMV). Sequence and mutational analyses of these clones showed genotypic and phenotypic diversity of the cloned virus population, but all examined clones had the adaptive mutation, A to C at position 776 within the BMV 3a gene, required for the systemic infection of cowpea. The data support the quasispecies model for RNA virus population, and suggest that the maintenance of the adaptive mutation may be due to powerful selection pressure in an infection process.