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Biomedical subjects

S Takayama

Publications and source records attributed to S Takayama.

At least 19 recordsLinked to original sources

Comparison of Campylobacter isolated from humans and food-producing animals in Japan.

AIMS: To compare the antimicrobial resistance, serotypes and flagellin gene types of Campylobacter isolated from humans and food-producing animals and thereby facilitate elucidation of the origin of Campylobacter causing human infection in Japan. METHODS AND RESULTS: The MIC values of ampicillin, dihydrostreptomycin, gentamicin, erythromycin, oxytetracycline, nalidixic acid and enrofloxacin for Campylobacter isolated from humans (134 isolates), cattle (38 isolates), pigs (69 isolates), layers (84 isolates) and broilers (51 isolates) were compared. The MIC(90) values of ampicillin for Campylobacter jejuni isolates from poultry were higher than those from humans and cattle. Campylobacter coli that was resistant to dihydrostreptomycin and erythromycin was observed at a higher frequency in humans and pigs than in poultry. The restriction fragment profiles of flaA of human, bovine and broiler isolates were analysed by clustering, and the isolates were classified into five clusters. Cluster I contained only human and bovine isolates. Clusters III, IV and V contained human, bovine and broiler isolates. CONCLUSIONS: Campylobacter isolates from humans included isolates that exhibited characteristics identical to those of the bovine, porcine and poultry isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: In addition to poultry, cattle and pigs are believed to be sources of campylobacteriosis in Japan.

Ampicillin↗

Ischaemic contracture in an infant's forearm--a case report.

We present a case of a gradually developing ischaemic contracture of the forearm muscles of an infant who developed without any trauma or acute gangrene at birth. Release of the middle and ring finger digitorum profundus muscles and pronator quadratus at 2 years of age corrected the deformity. Histopathology showed no evidence of fibromatosis or any other tumor. Although a dynamic splint was used to maintain the range of motion, the range of the middle finger motion deteriorated gradually 2 years after surgery. Though the pathogenesis of this problem was unclear, we assume that it was caused by fibrosis of muscles as a result of bleeding before or during delivery.

Compartment Syndromes↗

The S haplotypes lacking SLG in the genome of Brassica rapa.

Self-incompatibility (SI) discriminating self- and non-self pollen is regulated by S-locus genes in Brassica. In most of the S haplotypes, a highly polymorphic S-locus glycoprotein ( SLG) gene is tightly linked to genes for the SI determinants, S-receptor kinase ( SRK) and SP11, although the precise function of SLG in SI has not been clarified. In the present study, we performed DNA gel blot analysis for S(32), S(33), and S(36) haplotypes of Brassica rapa showing normal SI phenotypes and concluded that there might be no SLG in their genome. RNA gel blot analysis of the SLG-less S haplotypes indicated the possible existence of eSRK transcripts in the stigma. These three S haplotypes are useful resources to discern the molecular mechanism of the SI reaction without SLG.

Brassica↗

The shape of the triangular fibrocartilage during pronation-supination.

We studied the changes in the shape of the triangular fibrocartilage (TFC: disc proper) which occur during forearm rotation in disarticulated and articulated wrists. The influence of artificial 3mm ulnar lengthening on distortion of the disc was also examined. In the disarticulated wrists, slight distortion of the central and radial portions of the TFC was observed in the ulnar neutral variance specimens. More distortion was noted in the radial and central portions of the TFC in specimens with positive ulnar variance or with the ulna lengthened. However, in the articulated wrist, the TFC demonstrated little change in shape during pronosupination even in the ulnar positive variance wrists or with the ulna lengthened. There was no significant change in palmar and dorsal peripheral lengths of the TFC in ulnar neutral, ulnar positive or ulna-lengthened specimens at three rotatory positions of the forearm. These findings suggest that changes in ulnar variance which occur during forearm rotation can produce distortion on the TFC, but the carpus helps to maintain the shape of the TFC during pronation-supination, even with positive ulnar variance.

Aged↗

Recombinant human basic fibroblast growth factor (bFGF) stimulates periodontal regeneration in class II furcation defects created in beagle dogs.

Several growth factors (or cytokines) have been recently investigated for their use as potential therapeutics for periodontal tissue regeneration. The objective of this study was to evaluate periodontal tissue regeneration, including new bone and cementum formation, following topical application of recombinant basic fibroblast growth factor (bFGF, FGF-2) to furcation class II defects. Twelve furcation class II bone defects were surgically created in six beagle dogs, then recombinant bFGF (30 micro g/site) + gelatinous carrier was topically applied to the bony defects. Six weeks after application, periodontal regeneration was analyzed. In all sites where bFGF was applied, periodontal ligament formation with new cementum deposits and new bone formation was observed histomorphometrically, in amounts greater than in the control sites. Basic FGF-applied sites exhibited significant regeneration as represented by the new bone formation rate (NBR) (83.6 +/- 14.3%), new trabecular bone formation rate (NTBR) (44.1 +/- 9.5%), and new cementum formation rate (NCR) (97.0 +/- 7.5%). In contrast, in the carrier-only sites, the NBR, NTBR, and NCR were 35.4 +/- 8.9%, 16.6 +/- 6.2%, and 37.2 +/- 15.1%, respectively. Moreover, no instances of epithelial down growth, ankylosis, or root resorption were observed in the bFGF-applied sites examined. The present results indicate that topical application of bFGF can enhance considerable periodontal regeneration in artificially created furcation class II bone defects of beagle dogs.

Alveolar Process↗

Inhibitory effects of formoterol on lipopolysaccharide-induced premature delivery through modulation of proinflammatory cytokine production in mice.

Previous studies have demonstrated that formoterol, a beta2-adrenoceptor agonist, has potent tocolytic effects in rats. The aim of the present study was to determine whether formoterol treatment affects proinflammatory cytokine production in a lipopolysaccharide (LPS)-treated premature delivery mouse model. Formoterol was continuously administered by osmotic pump and the number of fetuses in the uteri were counted. Samples of amniotic fluid and plasma were collected 8 and 16 h after systemic administration of LPS. LPS induced premature delivery and an increase in prostaglandin F(2alpha) (PGF(2alpha)), interleukin 1alpha (IL-1alpha), IL-6 and IL-10 in the amniotic fluid, and an increase in IL-6 in plasma. Formoterol blocked all changes except the increase in IL-10. These data indicate that formoterol exerts inhibitory effects on proinflammatory cytokine production, and these effects may play an important role in the prevention of premature delivery.

Adrenergic beta-Agonists↗

Bag1 is a regulator and marker of neuronal differentiation.

Bag 1 acts as a co-chaperone for Hsp70/Hsc70. We report here that stable over-expression of Bag1 in immortalized neuronal CSM14.1 cells prevents death following serum deprivation. Bag1 over-expression slowed the proliferative rate of CSM14.1 cells, resulted in increased levels of phospo-MAP kinases and accelerated neuronal differentiation. Immunocytochemistry revealed mostly nuclear localization of Bag1 protein in these cells. However, during differentiation in vitro, Bag1 protein shifted from predominantly nuclear to mostly cytosolic in CSM14.1 cells. To explore in vivo parallels of these findings, we investigated Bag1 expression in the developing mouse nervous system using immunohistochemical methods. Early in brain development, Bag1 was found in nuclei of neuronal precursor cells, whereas cytosolic Bag1 staining was observed mainly after completion of neuronal precursor migration and differentiation. Taken together, these findings raise the possibility that the Bag1 protein is expressed early in neurogenesis in vivo and is capable of modulating neuronal cell survival and differentiation at least in part from a nuclear location.

Animals↗

Tocolytic activity of formoterol against premature delivery in mice.

The tocolytic activity of formoterol (eformoterol), a long-acting potent beta(2)-adrenoceptor agonist, was assessed in pregnant mice, with determination of uterine effects on the 15th and 16th days of gestation. For examination in the lipopolysaccharide-induced premature delivery model, osmotic pumps filled with formoterol or saline solution were implanted subcutaneously under the back skin. The mice were sacrificed 18-20 h thereafter, and the numbers of fetuses in the uteri and the newborn were counted. The uteri, amniotic membranes and placenta were also rapidly removed for determination of IL-6 concentrations. Furthermore, the effect of formoterol on IL-6 secretion from mouse amnion cells was determined. Formoterol and ritodrine inhibited contraction responses of isolated mouse uteri and their intravenous administration resulted in lowered uterine motility. Lipopolysaccharide (30 microg mL(-1)/mouse) induced premature delivery, attributable to increased IL-6 secretion, and formoterol suppressed this. Doses of 5-500 microg/mouse thus reduced the number of prematurely delivered newborn, and 50 microg/mouse also depressed IL-6 secretion. On histopathologic analysis, the marked oedema and slight haemorrhage in the mouse cervix induced by lipopolysaccharide were reduced by administration of the beta(2)-adrenoceptor agonist. Neither formoterol (10(-7)-10(-5) M) nor ritodrine (10(-7)-10(-5) M) influenced spontaneous secretion of IL-6 in amnion cells. However, at 10(-7) and 10(-5) M, and 10(-6) and 10(-5) M, respectively, they inhibited lipopolysaccharide-induced IL-6 secretion and this inhibitory effect was competitively reversed by addition of ICI-118,551 (beta(2)-adrenoceptor antagonist), but not atenolol (beta(1)-adrenoceptor antagonist). These findings strongly suggest that formoterol can suppress premature delivery mediated by its actions on IL-6 secretion.

Adrenergic Agonists↗

The carboxyl-terminal lobe of Hsc70 ATPase domain is sufficient for binding to BAG1.

The molecular co-chaperone BAG1 and other members of the BAG family bind to Hsp70/Hsc70 heat shock proteins through a conserved BAG domain that interacts with the ATPase domain of the chaperone. BAG1 and other accessory proteins stimulate ATP hydrolysis and regulate the ATP-driven activity of the chaperone complexes. Contacts are made through residues in helices alpha2 and alpha3 of the BAG domain and predominantly residues in the C-terminal lobe of the bi-lobed Hsc70 ATPase domain. Within the C-terminal lobe, a subdomain exists that contains all the contacts shown by mutagenesis to be required for BAG1 recognition. In this study, the subdomain, representing Hsc70 residues 229-309, was cloned and expressed as a separately folded unit. The results of in vitro binding assays demonstrate that this subdomain is sufficient for binding to BAG1. Binding analyses with surface plasmon resonance indicated that the subdomain binds to BAG1 with a 10-fold decrease in equilibrium dissociation constant (K(D) = 22 nM) relative to the intact ATPase domain. This result suggests that the stabilizing contacts for docking of BAG1 to Hsc70 are located in the C-terminal lobe of the ATPase domain. These findings provide new insights into the role of co-chaperones as nucleotide exchange factors.

Adenosine Triphosphatases↗

Characterization of expressed genes in the SLL2 region of self-compatible Arabidopsis thaliana.

Self-incompatibility in Brassica species is regulated by a set of S-locus genes: SLG, SRK, and SP11/SCR. In the vicinity of the S-locus genes, several expressed genes, SLL2 and SP2/ClpP, etc., were identified in B. campestris. Arabidopsis thaliana is a self-compatible Brassica relative, and its complete genome has been sequenced. From comparison of the genomic sequences between B. campestris and A. thaliana, microsynteny between gene clusters of Arabidopsis and Brassica SLL2 regions was observed, though the S-locus genes, SLG, SRK, and SP11/SCR were not found in the region of Arabidopsis. Almost all genes predicted in this region of Arabidopsis were expressed in both vegetative and reproductive organs, suggesting that the genes in the SLL2 region might not be related to self-incompatibility. Considering the recent speculation that the S-locus genes were translocated as a single unit between Arabidopsis and Brassica, the translocation might have occurred in the region between the SLL2 and SP7 genes.

Arabidopsis↗

Direct ligand-receptor complex interaction controls Brassica self-incompatibility.

Many higher plants have evolved self-incompatibility mechanisms to prevent self-fertilization. In Brassica self-incompatibility, recognition between pollen and the stigma is controlled by the S locus, which contains three highly polymorphic genes: S-receptor kinase (SRK), S-locus protein 11 (SP11) (also called S-locus cysteine-rich protein; SCR) and S-locus glycoprotein (SLG). SRK encodes a membrane-spanning serine/threonine kinase that determines the S-haplotype specificity of the stigma, and SP11 encodes a small cysteine-rich protein that determines the S-haplotype specificity of pollen. SP11 is localized in the pollen coat. It is thought that, during self-pollination, SP11 is secreted from the pollen coat and interacts with its cognate SRK in the papilla cell of the stigma to elicit the self-incompatibility response. SLG is a secreted stigma protein that is highly homologous to the SRK extracellular domain. Although it is not required for S-haplotype specificity of the stigma, SLG enhances the self-incompatibility response; however, how this is accomplished remains controversial. Here we show that a single form of SP11 of the S8 haplotype (S8-SP11) stabilized with four intramolecular disulphide bonds specifically binds the stigma membrane of the S8 haplotype to induce autophosphorylation of SRK8, and that SRK8 and SLG8 together form a high-affinity receptor complex for S8-SP11 on the stigma membrane.

Amino Acid Sequence↗

Expression profile of active genes in human periodontal ligament and isolation of PLAP-1, a novel SLRP family gene.

Periodontal ligament (PDL) is one of the most important tissues in maintaining the homeostasis of tooth and tooth-supporting tissue, periodontium. In this study, we investigated the expression profile of active genes in the human PDL obtained by collecting sequences with a 3'-directed cDNA library, which faithfully represents the composition of the mRNA population. We succeeded in obtaining a total of 1752 cDNA sequences by sequencing randomly selected clones and identified a total of 1318 different species as gene signatures (GS) by their sequence identity, 344 of which were known genes in the GenBank, and 974 of which were new genes. The resulting expression profile showed that collagen type I and type III were the most abundant genes and that osteogenesis-related proteins, such as SPARC/osteonectin and osteoblast specific factor 2, were highly expressed. By comparing the expression profile of PDL with 44 profiles similarly obtained with unrelated human cell/tissue, nine novel genes, which are probably expressed specifically in PDL, were discovered. Among them, we cloned a full-length cDNA of GS5096, which is frequently expressed in freshly-isolated periodontal tissue. We found that it encodes a novel protein, which is a new member of the class I small leucine-rich repeat proteoglycan family, and designated it PLAP-1 (periodontal ligament associated protein-1). PLAP-1 mRNA expression was confirmed in in vitro-maintained PDL cells and was enhanced during the course of the cytodifferentiation of the PDL cells into mineralized tissue-forming cells such as osteoblasts and cementoblasts. These findings suggest the involvement of PLAP-1 in the mineralized matrix formation in PDL tissues.

Amino Acid Sequence↗

BAG-1M, an isoform of Bcl-2-interacting protein BAG-1, enhances gene expression driven by CMV promoter.

BAG-1M, one of the isoforms of BAG-1, was reported to bind to DNA and stimulate general transcription when cells were stressed by heat shock (Zeiner, M., et al., Proc. Natl. Acad. Sci. USA 96, 10194-10199, 1999). Here we show that BAG-1M binds and enhances transcriptional activity of Cytomegalovirus (CMV) early gene promoter under unstressed conditions. This activity is unique to BAG-1M in that other isoforms, BAG-1S and BAG-1L, are much weaker in this activity, although all of the isoforms share common ubiquitin-like domain and BAG domain interacting with Hsp70/Hsc70. Deletion analysis of BAG-1M showed that C-terminal BAG domain is necessary to enhance the CMV promoter activity, suggesting that interaction with Hsp70/Hsc70 proteins may mediate this function. Another mutation in N-terminus, BAG-1M K(2-4)A, lost DNA binding capacity and majority of the promoter-enhancing activity. Our study demonstrates that both N-terminal DNA binding site and C-terminal Hsp70/Hsc70 binding site of BAG-1M play an important role in enhancing the CMV promoter activity.

Carrier Proteins↗

The anti-apoptotic protein BAG-3 is overexpressed in pancreatic cancer and induced by heat stress in pancreatic cancer cell lines.

Pancreatic cancer cells are usually resistant to apoptosis mediated by intrinsic or extrinsic factors. BAG-3 (Bis, CAIR), which was identified as a BAG-1-related protein, is a novel modulator of cellular anti-apoptotic activity that functions through its interaction with Bcl-2. In this study we analyzed BAG-3 expression in human pancreatic cancer tissues and cell lines. BAG-3 mRNA was expressed at moderate to high levels in all pancreatic cancer samples, but at low levels in normal pancreas tissues. In situ hybridization and immunohistochemistry analysis revealed that BAG-3 was present in the cancer cells within the pancreatic tumor mass. When BAG-3 mRNA was analyzed in other gastrointestinal cancers (hepatocellular carcinoma; esophageal, stomach and colon cancer), no difference was found from their corresponding normal controls. In pancreatic cancer cells, BAG-3 mRNA expression levels were strongly induced after heat stress, but not in response to members of the tumor necrosis factor (TNF)-alpha family (TNF-alpha, TRAIL, FasL). These findings indicate that in pancreatic cancer, in contrast to other gastrointestinal malignancies, increased levels of BAG-3 might function to block apoptosis. This characteristic of pancreatic cancer might contribute to its more aggressive growth behavior and poor responsiveness to treatment in vivo.

Adaptor Proteins, Signal Transducing↗

Nuclear BAG-1 localization and the risk of recurrence after radiation therapy in laryngeal carcinomas.

BAG-1 is a multifunctional chaperone modulator may contribute to p53-mediated cell cycle arrest. We attempted to investigate whether BAG-1 expression is correlated with prognosis of laryngeal carcinoma patients after radiotherapy. Immunohistochemical analyses revealed BAG-1 expression was present in all laryngeal carcinomas examined, and its expression pattern varied, i.e. cytoplasmic, nuclear and both these staining types. Patients whose tumors predominantly express nuclear BAG-1 have a significantly poor failure-free survival rate after radiotherapy. We thus propose that nuclear BAG-1 localization is a prediction of unfavorable outcome should radiation therapy be undertaken for laryngeal carcinoma patients.

Biomarkers, Tumor↗

Dual targeting of spinach protoporphyrinogen oxidase II to mitochondria and chloroplasts by alternative use of two in-frame initiation codons.

Protoporphyrinogen oxidase (Protox) is the final enzyme in the common pathway of chlorophyll and heme biosynthesis. Two Protox isoenzymes have been described in tobacco, a plastidic and a mitochondrial form. We isolated and sequenced spinach Protox cDNA, which encodes a homolog of tobacco mitochondrial Protox (Protox II). Alignment of the deduced amino acid sequence between Protox II and other tobacco mitochondrial Protox homologs revealed a 26-amino acid N-terminal extension unique to the spinach enzyme. Immunoblot analysis of spinach leaf extract detected two proteins with apparent molecular masses of 57 and 55 kDa in chloroplasts and mitochondria, respectively. In vitro translation experiments indicated that two translation products (59 and 55 kDa) are produced from Protox II mRNA, using two in-frame initiation codons. Transport experiments using green fluorescent protein-fused Protox II suggested that the larger and smaller translation products (Protox IIL and IIS) target exclusively to chloroplasts and mitochondria, respectively.

Amino Acid Sequence↗