Enterovirus encephalomyelitis in pigs in Japan caused by porcine teschovirus.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
R Ikegami
Publications and source records attributed to R Ikegami.
Baseball pitcher's friction dermatitis.
Explore the source record for details and available documents.
Administration, Oral↗
The expression of prostaglandin E receptors EP2 and EP4 and their different regulation by lipopolysaccharide in C3H/HeN peritoneal macrophages.
The expression and regulation of the PGE receptors, EP(2) and EP(4), both of which are coupled to the stimulation of adenylate cyclase, were examined in peritoneal resident macrophages from C3H/HeN mice. mRNA expression of EP(4) but not EP(2) was found in nonstimulated cells, but the latter was induced by medium change alone, and this induction was augmented by LPS. mRNA expression of EP(4) was down-regulated by LPS but not by medium change. PGE(2) increased the cAMP content of both LPS-treated and nontreated cells. ONO-604, an EP(4) agonist, also increased cAMP content in nonstimulated cells and in cells treated with LPS for 3 h, but not for 6 h. Butaprost, an EP(2) agonist, was effective only in the cells treated with LPS for 6 h. The inhibitory effects of ONO-604 on TNF-alpha and IL-12 production were equipotent with PGE(2) at any time point, but the inhibitory effects of butaprost were only seen from 14 h after stimulation. PGE(2) or dibutyryl cAMP alone, but not butaprost, reduced EP(4) expression, and indomethacin reversed the LPS-induced down-regulation of EP(4), indicating that the down-regulation of EP(4) is mediated by LPS-induced PG synthesis and EP(4) activation. Indeed, when we used C3H/HeJ (LPS-hyporesponsive) macrophages, such reduction in EP(4) expression was found in the cells treated with PGE(2) alone, but not in LPS-treated cells. In contrast, up-regulation of EP(2) expression was again observed in LPS-treated C3H/HeJ macrophages. These results suggest that EP(4) is involved mainly in the inhibition of cytokine release, and that the gene expression of EP(2) and EP(4) is differentially regulated during macrophage activation.
Alprostadil↗
Developmental activation of the capability to undergo checkpoint-induced apoptosis in the early zebrafish embryo.
In this study, we demonstrate the developmental activation, in the zebrafish embryo, of a surveillance mechanism which triggers apoptosis to remove damaged cells. We determine the time course of activation of this mechanism by exposing embryos to camptothecin, an agent which specifically inhibits topoisomerase I within the DNA replication complex and which, as a consequence of this inhibition, also produces strand breaks in the genomic DNA. In response to an early (pre-gastrula) treatment with camptothecin, apoptosis is induced at a time corresponding approximately to mid-gastrula stage in controls. This apoptotic response to a block of DNA replication can also be induced by early (pre-MBT) treatment with the DNA synthesis inhibitors hydroxyurea and aphidicolin. After camptothecin treatment, a high proportion of cells in two of the embryo's three mitotic domains (the enveloping and deep cell layers), but not in the remaining domain (the yolk syncytial layer), undergoes apoptosis in a cell-autonomous fashion. The first step in this response is an arrest of the proliferation of all deep- and enveloping-layer cells. These cells continue to increase in nuclear volume and to synthesize DNA. Eventually they become apoptotic, by a stereotypic pathway which involves cell membrane blebbing, "margination" and fragmentation of nuclei, and cleavage of the genomic DNA to produce a nucleosomal ladder. Fragmentation of nuclei can be blocked by the caspase-1,4,5 inhibitor Ac-YVAD-CHO, but not by the caspase-2,3,7[, 1] inhibitor Ac-DEVD-CHO. This suggests a functional requirement for caspase-4 or caspase-5 in the apoptotic response to camptothecin. Recently, Xenopus has been shown to display a developmental activation of the capability for stress- or damaged-induced apoptosis at early gastrula stage. En masse, our experiments suggest that the apoptotic responses in zebrafish and Xenopus are fundamentally similar. Thus, as for mammals, embryos of the lower vertebrates exhibit the activation of surveillance mechanisms, early in development, to produce the selective apoptosis of damaged cells.
Animals↗
Characterization of the LPS-stimulated expression of EP2 and EP4 prostaglandin E receptors in mouse macrophage-like cell line, J774.1.
The expression of prostaglandin (PG) E receptor subtypes were characterized in J774.1, a mouse macrophage-like cell line. EP2- and EP4-mRNAs were found to be expressed. The expression of EP2 mRNA increased by the addition of lipopolysaccharide (LPS) in a dose-dependent manner. EP2 mRNA rapidly increased by more than 5-fold of the control level at 1 h, and decreased after 4 h. EP4 mRNA increased by only 2-fold of the control at 2 h. Gamma interferon inhibited both basal and LPS-induced expression of EP2 mRNA but did not affect the expression level of EP4 mRNA. When tumor necrosis factor-alpha (TNF-alpha) accumulation was measured after the treatment ofthe cells with LPS for 90 min, PGE2 was found to inhibit this accumulation, but butaprost, an EP2-selective agonist, did not. When TNF-alpha release was measured after the treatment of the cells with LPS for 8 h, accumulation was inhibited by butaprost as well as PGE2. These results indicated that the inhibitory effects of PGE2 on TNF-alpha production are mediated by EP2 and EP4 in macrophages, and that expression regulation of EP2 and EP4 in macrophages is quite different.
Alprostadil↗
Characterization of the gene for the mouse prostaglandin E receptor subtype EP2: tissue-specific initiation of transcription in the macrophage and the uterus.
Genomic DNA clones for the mouse prostaglandin (PG) E receptor subtype EP2 were isolated and characterized. The mouse EP2 gene is composed of 2 exons and 1 intron, and spans 16 kb. The intron which is approx. 12 kb in length is located at the end of the sixth transmembrane domain, as with other prostanoid receptor genes. Based on this structure, transcripts were analysed in endotoxin-treated macrophages and pseudopregnant uteri, in which abundant expression of EP2 mRNA was observed. Sequence analysis of cDNA clones from these origins and Northern hybridization of these RNAs revealed that the uterine EP2 mRNA (U-type) has a longer 5'-untranslated region than the macrophage EP2 transcript (M-type). The major transcription initiation sites for M-type and U-type EP2 are located 124 and 769 bp upstream of the translation start site, respectively. The M-type was expressed in various tissues, whereas the U-type was found only in the uterus. The 2 kb segment containing the immediate 5'-flanking and 5'-noncoding regions contain three consensus sequences for the NF-IL6 binding site, one consensus sequence for the NF-kappaB binding site, four AP-2 consensus sequences, one AP-4 consensus sequence, one potential cAMP response element, and one potential progesterone response element. These results suggest that EP2 gene expression in the macrophage and uterus is under the control of distinct mechanisms involving alternative promoters.
Amino Acid Sequence↗
Effect of inhibitors of DNA replication on early zebrafish embryos: evidence for coordinate activation of multiple intrinsic cell-cycle checkpoints at the mid-blastula transition.
We address the developmental activation, in the zebrafish embryo, of intrinsic cell-cycle checkpoints which monitor the DNA replication process and progression through the cell cycle. Eukaryotic DNA replication is probably carried out by a multiprotein complex containing numerous enzymes and accessory factors that act in concert to effect processive DNA synthesis (Applegren, N. et al. (1995) J. Cell. Biochem. 59, 91-107). We have exposed early zebrafish embryos to three chemical agents which are predicted to specifically inhibit the DNA polymerase alpha, topoisomerase I and topoisomerase II components of the DNA replication complex. We present four findings: (1) Before mid-blastula transition (MBT) an inhibition of DNA synthesis does not block cells from attempting to proceed through mitosis, implying the lack of functional checkpoints. (2) After MBT, the embryo displays two distinct modes of intrinsic checkpoint operation. One mode is a rapid and complete stop of cell division, and the other is an 'adaptive' response in which the cell cycle continues to operate, perhaps in a 'repair' mode, to generate daughter nuclei with few visible defects. (3) The embryo does not display a maximal capability for the 'adaptive' response until several hours after MBT, which is consistent with a slow transcriptional control mechanism for checkpoint activation. (4) The slow activation of checkpoints at MBT provides a window of time during which inhibitors of DNA synthesis will induce cytogenetic lesions without killing the embryo. This could be useful in the design of a deletion-mutagenesis strategy.
Animals↗
Activation of the metaphase checkpoint and an apoptosis programme in the early zebrafish embryo, by treatment with the spindle-destabilising agent nocodazole.
We have studied the developmental activation of the metaphase checkpoint, and the consequences of activating this checkpoint, in the zebrafish embryo. (1) Treatment with nocodazole (a microtubule destabiliser) before mid-blastula transition (MBT) produces complete destruction of all nuclei in the deep cell layer of the embryo. In contrast, nocodazole treatment after MBT efficiently produces metaphase arrest in this cell layer. Thus, the metaphase checkpoint becomes activated at MBT. (2) Although a metaphase arrest is induced by nocodazole, it is not induced by paclitaxel (a microtubule stabiliser). Thus the metaphase checkpoint appears to sense a destabilisation, but not a stabilisation, of spindle microtubules. (3) Metaphase-arrested cells (in nocodazole) can be driven into the next interphase by adding the Ca2+-specific ionophore A23187. Thus, a Ca2+-signalling pathway lies downstream of, or parallel to, the metaphase checkpoint. (4) After mid-gastrula stage, treatment with nocodazole produces DNA fragmentation in all three cell layers. In the enveloping epithelial monolayer (EVL), this is associated with a classical apoptotic phenotype. In the deep layer, it is associated with an unusual, highly condensed nuclear state that is entered directly from metaphase arrest. Thus, after the mid-gastrula stage, the embryo responds to nocodazle by undergoing apoptosis. (5) Nocodazole-induced apoptosis in the deep cell layer can be blocked by the caspase-1,4,5 inhibitors Ac-YVAD-CHO and Ac-YVAD-CMK. This suggests that a homologue of the C. elegans ced-9-ced-4-ced-3 pathway is involved in control over apoptosis in the early zebrafish embryo.
Amino Acid Chloromethyl Ketones↗
High-resolution imaging at the cellular and subcellular levels in flattened whole mounts of early zebrafish embryos.
We describe a rapid and sensitive method for high-resolution imaging at the cellular and subcellular levels in the whole-mount zebrafish embryo. The procedure involves fixing and staining the embryo, followed by deyolking and flattening it under a cover slip, to produce a planar mount that is 20 to 100 microns thick. Such a flattened whole mount allows imaging with a spatial resolution of approximately 500 nm in the x-y plane and does not require the use of embedding, sectioning, confocal microscopy, or computational deblurring procedures. We can resolve all individual nuclei and chromosome sets in the embryo, up to the late gastrula stage (10,000 cell stage). In addition, older embryos (through the segmentation stage) can also be examined, with the preservation of significant morphological detail. Because of its ability to resolve subcellular detail, the flattened whole-mount method can provide significant biological information beyond what can be obtained from conventional (three-dimensional) whole mounts. We have used the flattened whole-mount method to study subcellular events related to progression through the cell cycle or to apoptosis, in cells of the early zebrafish embryo. A specific DNA-binding dye (Hoechst 33258) or an antibody against a chromosomal protein (histone H1) was used to stain the nuclei of individual cells in the embryo. This allowed us to determine the spatial positions of all the individual cells, and also their stages in the cell cycle. A terminal transferase (TUNEL) assay was used to detect apoptotic cells. This combination of specific stains allowed us to study the behaviors of groups of cells in situ, within the developing zebrafish embryo.
Animals↗
4-Methylcatechol, an inducer of nerve growth factor synthesis, enhances peripheral nerve regeneration across nerve gaps.
The effect on peripheral nerve regeneration of 4-methylcatechol (MC), which is a potent inducer of nerve growth factor (NGF) synthesis in vitro and in vivo, was examined in a sciatic nerve-lesioned animal model. The sciatic nerve of adult male Wistar rats was transected and both of the cut ends were then inserted into sterile silicone tubes that were subsequently attached to an intervening silicone chamber. After surgery, the rats were injected i.p. every day for 2 weeks with MC. Two weeks after surgery, the density of nonmyelinated axons within the chamber was significantly increased in the MC-treated group compared with that in the control group. Five weeks after surgery, both the number and the diameter of myelinated axons within the chamber of the MC-treated group were significantly larger than those of the control group. When the chamber was filled with anti-NGF antibody solution, most of the MC effect was blocked. These results suggest that MC stimulates de novo synthesis of NGF (and/or NGF-related molecules), which results in the enhancement of sprouting and maturation of peripheral axons.
Animals↗
Pharmacological induction of physiologically active nerve growth factor in rat peripheral nervous system.
Intraperitoneal administration of 4-methylcatechol, which is one of the potent stimulators of nerve growth factor (NGF) synthesis in vitro, induced an increase in NGF protein and NGF mRNA in the adult rat heart and submaxillary gland. The increase in NGF protein was successively translocated from the sciatic nerve to sensory or sympathetic ganglia. Repetitive administration of 1,2-diacetoxypropylbenzene, an acetylated form of 4-methylcatechol analog, caused significant elevations of substance P levels in sensory ganglia and tyrosine hydroxylase activity in superior cervical ganglia of infant rats. These observations suggest that both compounds could stimulate NGF synthesis in vivo and that the induced NGF had physiological effects on peripheral neurons.
Animals↗
[Changes of nerve growth factor (NGF) content in injured peripheral nerve during regeneration: local synthesis of NGF by Schwann cells].
NGF content in rat sciatic nerve was investigated using an enzyme immunoassay. Following nerve transection, NGF level increased at the distal side to transection. These NGF increases consisted of an initial rapid increase which might be due to retrograde axonal transport from peripheral organs, and also a secondly slow increase which appeared to be a result of local synthesis. Local synthesis of NGF in the nerve was confirmed by the findings that NGF content increased in the free segment between the two transection sites, and also in the cultured nerve segments where axonal transport could be neglected. Schwann cells and fibroblasts cultured from the sciatic nerve were found to secrete NGF suggesting the local synthesis of NGF by these cells in vivo. NGF accumulated by axonal transport and locally synthesized by non-neuronal cells in the distal side to transection, that is, the regenerating portion, might play an important role in nerve regeneration.
Animals↗
Studies on the induction of tolerance to alloantigens. III. Induction of antibodies directed against alloantigen-specific delayed-type hypersensitivity T cells by a single injection of allogeneic lymphocytes via portal venous route.
BALB/c mice were inoculated with normal C3H/He spleen cells via the portal venous (p.v.) route. Intravenous injection of serum from these BALB/c mice into naive syngeneic mice resulted in almost complete abrogation of their ability to generate anti-C3H/He delayed-type hypersensitivity (DTH) responses as induced by s.c. immunization with C3H/He cells. Since a portion of the same serum did not inhibit the development of anti-C57BL/6 DTH responses, the suppressive effect of the transferred serum was alloantigen-specific. Such serum factor(s) was produced in normal but not in nude mice and the suppressive activity was transferred in H-2- or immunoglobulin allotype-incompatible combinations. Immunochemical analyses of this serum suppressive factor have revealed that its m.w. was approximately 150,000, corresponding to the size of immunoglobulin (Ig)G, and that the activity was trapped by protein A or by an anti-immunoglobulin column. Although the absorption of the serum from anti-C3H/He-tolerant BALB/c mice with C3H/He target spleen cells did not abrogate the suppressive activity, the additional absorption with spleen cells from anti-C3H/He hyperimmune BALB/c mice almost completely eliminated the suppressive potential. Moreover, pretreatment of BALB/c anti-C3H/He DTH effector spleen cells with the above serum from tolerant mice induced the inhibition of anti-C3H/He DTH responses. Taken together, these results indicate that a single injection of allogeneic cells via the p.v. route results in the production of antibody capable of inhibiting the capacity of DTH effector cells specific for alloantigens used for the p.v. presensitization.
Animals↗
Tolerance induction of alloreactivity by portal venous inoculation with allogeneic cells followed by the injection of cyclophosphamide. II. Cellular and molecular mechanisms underlying tolerance.
BALB/c mice receiving allogeneic C3H/He or C57BL/6 spleen cells via portal venous (p.v.) route or a single administration of cyclophosphamide (Cy) were capable of rejecting the respective allogeneic C3H/He- or C57BL/6-derived tumor cells. In contrast, the combined treatment of p.v. inoculation with allogeneic lymphocytes and Cy administration abrogated the capability of rejecting allogeneic tumor cells. Such abrogation of alloreactivity was alloantigen-specific and associated with the suppression of potentials to generate delayed-type hypersensitivity (DTH) and cytotoxic T lymphocyte (CTL) responses to alloantigens. This was further substantiated by the inhibition of molecular mechanisms underlying anti-allo-DTH and -CTL responses. Thus, the above combined treatment led to the decreased production of lymphokines such as macrophage-activating factor (MAF) and interleukin 2 (IL2) following the stimulation with the relevant alloantigens. These results demonstrate that p.v. inoculation of allogeneic cells followed by a single administration of Cy results in the effective elimination of alloreactivity as verified by the suppression of cellular and molecular mechanisms of alloreactive responses.
Animals↗
Abrogation of the capacity of delayed-type hypersensitivity responses to alloantigens by intravenous injection of neuraminidase-treated allogeneic cells.
BALB/c or C3H/He mice were inoculated i.v. with allogeneic spleen cells untreated or treated with neuraminidase. Appreciable or potent anti-allo-delayed-type hypersensitivity (DTH) responses were observed when mice were inoculated i.v. with untreated allogeneic cells or inoculated i.v. with those cells followed by s.c. immunization with untreated allogeneic cells. In contrast, i.v. inoculation of neuraminidase-treated allogeneic cells (presensitization) not only failed to induce any significant anti-allo-DTH responses but also abolished the capability of the animals to develop DTH responses after s.c. immunization, indicating the tolerance induction. This tolerance was alloantigen-specific, and rapidly inducible and long lasting. The induction of suppressor cell activity was demonstrated in tolerant mice. However, this activity was associated only with the tolerant state around 4 to 7 days after the i.v. presensitization, but was no longer detected in mice more than 14 days after the presensitization, although these mice exhibited complete tolerant state. When spleen cells from such tolerant mice were transferred i.v. into 600 R x-irradiated syngeneic recipient mice alone or together with normal syngeneic spleen cells, these tolerant spleen cells themselves failed to induce DTH responses but did not exhibit suppressive effect on the generation of DTH responses induced by normal spleen cells co-transferred. These results indicate that i.v. administration of neuraminidase-treated allogeneic cells results in the induction of alloantigen-specific tolerance which is not always associated with the induction of suppressor cell activity but rather with the elimination or functional impairment of alloantigen-specific clones.
Animals↗
Studies on the induction of tolerance to alloantigens. II. The generation of serum factor(s) able to transfer alloantigen-specific tolerance for delayed-type hypersensitivity by portal venous inoculation with allogeneic cells.
The administration of C3H/He spleen cells into allogeneic BALB/c mice via portal venous (p.v.) route resulted in C3H/He alloantigen-specific tolerance for delayed-type hypersensitivity (DTH) responses. When serum from these tolerant BALB/c mice were transferred into naive syngeneic BALB/c mice, the recipient mice lost the capability of generating DTH responses as induced by s.c. immunization with C3H/He cells. Tolerance was transferred only by serum from BALB/c mice inoculated p.v. with C3H/He cells, but not by serum from C3H/He mice inoculated p.v. with C3H/He cells, or BALB/c mice inoculated i.v. with C3H/He cells. This tolerogenic activity in serum from p.v. inoculated BALB/c mice was C3H/He alloantigen specific, because the transfer of the serum did not interfere with the development of anti-C57BL/6 DTH responses in recipient BALB/c mice. Such a serum factor(s) was inducible as early as 1 wk after the inoculation of C3H/He cells into BALB/c mice and not associated with anti-C3H/He alloantibody activity. Moreover, anti-C3H/He or C57BL/6-specific tolerogenic factor(s) prepared in the respective BALB/c or C3H/He mice was successfully transferred into totally allogeneic recipient mice, indicating no requirement of H-2, as well as non-H-2 restriction for the function of serum tolerogenic factor(s). Thus this study demonstrates that p.v. inoculation of allogeneic cells generates serum factor(s) able to transfer in H-2 and non-H-2-unrestricted manners the in vivo tolerance of the alloreactivity specific for alloantigens used for p.v. inoculation.
Animals↗
[A clinical bacteriological efficacy study on a fosfomycin otic solution].
Fosfomycin (FOM) otic solution was administered to 587 patients with suppurative otitis media infections including 190 patients in the dose-establishment test, 126 patients in the open clinical trial and 271 patients in the double blind test. Various bacteria were detected in the 549 cases in which bacteriological investigation was possible. Main bacteria detected from the above cases were S. aureus (261 strains, 47.5%), P. aeruginosa (93 strains, 16.9%), coagulase negative Staphylococci (CNS) (89 strains, 16.2%), Providencia spp. (35 strains, 6.4%) and Proteus spp. (28 strains, 5.1%). Twenty-seven strains of anaerobic bacteria (4.9%) were also detected. The MIC of FOM, and the reference drug, chloramphenicol (CP), fradiomycin (FRM), cefmenoxime (CMX) and cephalexin (CEX), were determined up to a concentration of 800 micrograms/ml with inoculum sizes of 10(6) and 10(8) CFU/ml. About 30% of S. aureus was multi-drug resistant, including methicillin and cephems, but FOM showed excellent antibacterial activity against it. The FOM had superior antibacterial activity against P. aeruginosa to CP, FRM and CMX, and was also active against other bacteria. The antibacterial activity of FOM was inferior to other drugs against CNS, Enterobacter spp., P. putida and P. cepacia. The detection rate of these bacteria, however, was low and since their role as causative organisms is not well defined, the inferior activity of FOM has no effect on the bacteriological evaluation of FOM. Since the concentration in the tympanic cavity about 1 hour after the administration of 3% FOM solution was estimated to be 2,000 to 3,000 micrograms/ml, it could be presumed that bacteria inhibited by 800 micrograms/ml of FOM at an inoculum size of 10(8) CFU/ml would be eradicable. The low ototoxicity of FOM is likely due to its characteristic as an inhibitor of bacterial cell wall synthesis. From these results, 3% FOM otic solution may be considered as a remarkably useful topical preparation for the treatment of suppurative otitis media.
Administration, Topical↗
[In vitro susceptibilities of BRL 25000 (clavulanic acid-amoxicillin) against causative organisms in the field of obstetrics and gynecology].
The in vitro susceptibilities of various causative organisms recently isolated from patients with genital infections to BRL 25000 (a formulation with 2 parts of amoxicillin and 1 part of potassium clavulanate), amoxicillin (AMPC), cefaclor (CCL), cephalexin (CEX), cefadroxil (CDX) and cefroxadine (CXD) were determined. beta-Lactamase-producing strains were detected by the nitrocefin disc method. Frequencies of isolation of beta-lactamase producing strains of E. coli, K. pneumoniae and B. fragilis were 36%, 96% and 100%, respectively. The activity of BRL 25000 against S. agalactiae and anaerobic GPC (anaerobic Streptococci, Peptostreptococcus spp.) was slightly less than that of AMPC but was 2- to 4-fold higher than CCL and 8- to 16-fold higher than CEX, CDX and CXD. Against E. coli and K. pneumoniae, the activity of BRL 25000 was superior to that of AMPC and approximately equal to CEX, CDX and CXD but 2-fold less than CCL. Against the B. fragilis group, BRL 25000 was much more active than AMPC or any of the cephalosporins tested, clearly demonstrating the beta-lactamase inhibitory properties of the clavulanic acid in BRL 25000. At inocula of 10(6) CFU/ml, MIC values of BRL 25000 were 12.5-50 micrograms/ml against some strains of E. coli, K. pneumoniae and B. fragilis. A mechanism of resistance other than beta-lactamase production is obviously prevalent in these strains. It is speculated that the resistance may be due to a low affinity of the drug to target proteins. Mixed infections of B. fragilis and E. coli or K. pneumoniae are commonly found in the obstetric and gynecological patients. BRL 25000 shows activity against these strains and also against both aerobic and anaerobic GPC. Therefore, BRL 25000 is considered useful for the treatment of genital infections.
Amoxicillin↗