Interleukin-12 augments cytolytic activity of peripheral blood mononuclear cells against autologous lung cancer cells in combination with IL-2

The majority of patients with advanced lung cancer die within a few years. Accordingly, new therapeutic modalities need to be developed. Interleukin (IL)-12 was previously known as natural killer (NK) cell stimulatory factor or cytotoxic lymphocyte maturation factor. By virtue of its effects on T cells and NK cells, IL-12 seems to be one of the key cytokines that regulates cell-mediated anti tumor immune responses. Recently, there has been a substantial interest in the potential applications of IL-12 in the treatment of lung cancer. However, there have been no reports about the effect of IL-12 on peripheral blood mononuclear cells (PBMCs) obtained from lung cancer patients in an autologous setting. In this study, we examined the cytotoxicity of PBMC activated by IL-2, IL-12 or both against K562 or autologous lung cancer cells. In contrast to the effect of IL-2 on NK activity, IL-12 alone augmented NK activity against K562 cells, but not against autologous lung cancer cells. IL-12 augmented the IL-2 mediated cytotoxicity of PBMC against both K562 and autologous lung cancer cells. In the absence of IL-2, IL-12 alone cannot induce an autologous anti-tumor effect in vivo. In summary, our results clearly demonstrated that IL-12 can augment the cytolytic activity of PBMC against K562 and autologous lung cancer cells when combined with IL-2, although, IL-12 alone was unable to induce a marked increase in the cytotoxicity against autologous lung cancer cells. These results suggest that an administration of IL-12 in combination with IL-2 may be a useful therapeutic option for solid tumors.

T-bet is rapidly induced by interferon-gamma in lymphoid and myeloid cells

Differentiation of naive CD4(+) T cells into IFN-gamma-producing T helper 1 (T(H)1) cells is pivotal for protective immune responses against intracellular pathogens. T-bet, a recently discovered member of the T-box transcription factor family, has been reported to play a critical role in this process, promoting IFN-gamma production. Although terminal T(H)1 differentiation occurs over days, we now show that challenge of mice with a prototypical T(H)1-inducing stimulus, Toxoplasma gondii soluble extract, rapidly induced IFN-gamma and T-bet; T-bet induction was substantially lower in IFN-gamma-deficient mice. Naive T cells expressed little T-bet, but this transcription factor was induced markedly by the combination of IFN-gamma and cognate antigen. Human myeloid antigen-presenting cells showed T-bet induction after IFN-gamma stimulation alone, and this induction was antagonized by IL-4 and granulocyte/macrophage colony-stimulating factor. Although T-bet was induced rapidly and directly by IFN-gamma, it was not induced by IFN-alpha, lipopolysaccharide, or IL-1, indicating that this action of IFN-gamma was specific. Moreover, T-bet induction was dependent on Stat1 but not Stat4. These data argue for a model in which IFN-gamma gene regulation involves an autocrine loop, whereby the cytokine regulates a transcription factor that promotes its own production. These findings substantially alter the current view of T-bet in IFN-gamma regulation and promotion of cell-mediated immune responses.

Preparation of a novel core-shell nanostructured gold colloid-silk fibroin bioconjugate by the protein in situ redox technique at room temperature

A novel core-shell gold colloid-silk fibroin (SF) bioconjugate was prepared by the protein in situ redox technique at room temperature, in which the tyrosine (Tyr) residue of the SF, having strong electron donating properties, in situ reduced Au(III) ions to Au colloids showing a stable and highly monodispersed nature.

IL-18-binding protein protects against lipopolysaccharide- induced lethality and prevents the development of Fas/Fas ligand-mediated models of liver disease in mice

IL-18-binding protein (IL-18BP) is a natural IL-18 inhibitor. Human IL-18BP isoform a was produced as fusion construct with human IgG1 Fc and assessed for binding and neutralizing IL-18. IL-18BP-Fc binds human, mouse, and rat IL-18 with high affinity (K(D) 0.3-5 nM) in a BIAcore-based assay. In vitro, IL-18BP-Fc blocks IL-18 (100 ng/ml)-induced IFN-gamma production by KG1 cells (EC(50) = 0.3 microg/ml). In mice challenged with an LD(90) of LPS (15 mg/kg), IL-18BP-Fc (5 mg/kg) administered 10 min before LPS blocks IFN-gamma production and protects against lethality. IL-18BP-Fc administered 10 min before LPS blocks IFN-gamma production induced by LPS (5 mg/kg) with ED(50) of 0.005 mg/kg. Furthermore, IL-18BP-Fc (5 mg/kg) abrogates LPS (5 mg/kg)-induced IFN-gamma production even when administered 6 days before LPS but shows no effect when administered 9 or 12 days before LPS. Given 10 min before LPS challenge to mice primed 12 days in advance with heat-killed Propionibacterium acnes, IL-18BP-Fc prevents LPS-induced liver damage and IFN-gamma and Fas ligand expression. Given at the moment of priming with P. acnes, IL-18BP-Fc decreases P. acnes-induced granuloma formation, macrophage-inflammatory protein-1alpha and macrophage-inflammatory protein-2 production and prevents sensitization to LPS. IL-18BP-Fc also prevents Con A-induced liver damage and IFN-gamma and Fas ligand expression as well as liver damage induced by Pseudomonas aeruginosa exotoxin A or by anti-Fas agonistic Ab. In conclusion, IL-18BP can be engineered and produced in recombinant form to generate an IL-18 inhibitor, IL-18BP-Fc, endowed with remarkable in vitro and in vivo properties of binding and neutralizing IL-18.

Involvement of gibberellins in expression of a cysteine proteinase (SH-EP) in cotyledons of Vigna mungo seedlings

The expression of a papain-type proteinase, designated SH-EP, in cotyledons of Vigna mungo seedlings has been shown to require some factors in the embryonic axes. Gibberellin A1 (GA(1)) and GA(20) were identified by GC-MS in embryonic axes of V. mungo seedlings. The level of accumulation of SH-EP in cotyledons of V. mungo seedlings was greatly reduced by treatment of the seeds with uniconazole-P, an inhibitor for GA biosynthesis. The reduced level of accumulation of SH-EP in cotyledons by uniconazole-P was recovered by exogenous application of GA(1) and GA(20) to the seedlings.

Glistening formation in an AcrySof lens initiated by spinodal decomposition of the polymer network by temperature change

PURPOSE

To examine the effect of temperature change on the structural alteration and glistening formation in an AcrySof intraocular lens (IOL).

SETTING

Department of Chemical Science and Engineering, Faculty of Engineering, Kobe University, Kobe, Japan.

METHODS

The equilibrium water content of a Wagon-Wheel-packaged AcrySof IOL was determined at various temperatures by the gravimetrical method. Alterations in the microscopic structure of the lens were analyzed in situ with a reflecting microscope without staining, while the temperature of the lens was changed at different rates.

RESULTS

Microvacuoles of 1.0 to 20.0 microm formed in the bulk of a swollen AcrySof IOL as the temperature decreased. The morphology of the vacuoles was similar to that of glistening particles observed in vivo. The size and density of the glistening-like vacuoles varied depending on the magnitude and rate of the temperature decrease. The glistening-like vacuoles were imprinted in the bulk of the IOL during the preceding cooling process in aqueous humor.

CONCLUSIONS

Glistenings formed in the bulk of an AcrySof IOL as the medium temperature decreased. The mechanism may involve spinodal decomposition of the swollen polymer network, which initiates the formation of microvacuoles consisting of water and loosely packed network chains.

Functional and evolutionary relationship between arginine biosynthesis and prokaryotic lysine biosynthesis through alpha-aminoadipate

Our previous studies revealed that lysine is synthesized through alpha-aminoadipate in an extremely thermophilic bacterium, Thermus thermophilus HB27. Sequence analysis of a gene cluster involved in the lysine biosynthesis of this microorganism suggested that the conversion from alpha-aminoadipate to lysine proceeds in a way similar to that of arginine biosynthesis. In the present study, we cloned an argD homolog of T. thermophilus HB27 which was not included in the previously cloned lysine biosynthetic gene cluster and determined the nucleotide sequence. A knockout of the argD-like gene, now termed lysJ, in T. thermophilus HB27 showed that this gene is essential for lysine biosynthesis in this bacterium. The lysJ gene was cloned into a plasmid and overexpressed in Escherichia coli, and the LysJ protein was purified to homogeneity. When the catalytic activity of LysJ was analyzed in a reverse reaction in the putative pathway, LysJ was found to transfer the epsilon-amino group of N(2)-acetyllysine, a putative intermediate in lysine biosynthesis, to 2-oxoglutarate. When N(2)-acetylornithine, a substrate for arginine biosynthesis, was used as the substrate for the reaction, LysJ transferred the delta-amino group of N(2)-acetylornithine to 2-oxoglutarate 16 times more efficiently than when N(2)-acetyllysine was the amino donor. All these results suggest that lysine biosynthesis in T. thermophilus HB27 is functionally and evolutionarily related to arginine biosynthesis.

Impairment in the expression and activity of Fyn during differentiation of naive CD4+ T cells into the Th2 subset

We previously showed that the amounts of Fyn protein in Th2 clones were approximately one-third to one-fifth of those in Th1 clones. In this study we examined the role of Fyn in the polarization of naive CD4+ T cells toward the Th2 subset using fyn(-/-) mice. The fyn(-/-) naive CD4+ T cells efficiently produced Th2 cytokines and polarized toward the Th2 subset even in the absence of IL-4 and IL-13. The expression of Fyn in wild-type CD4+ T cells decreased at a transcription level concomitant with polarization toward the Th2 subset. These results suggest that Fyn plays a role in the down-regulation of the differentiation of naive CD4+ T cells into the Th2 subset.

Characterization of aspartate kinase III of Bacillus subtilis

A search in the Bacillus subtilis genome sequence found that the gene designated yclM encode(s) a protein showing significant identity in amino acid sequence to aspartate kinases. When yclM was introduced into Escherichia coli cells deficient in all three aspartate kinase genes, production of a protein with molecular size 50 kDa, which was similar to the value deduced from the nucleotide sequence of the gene, was observed. Expectedly, the protein purified to homogeneity had aspartate kinase activity. The enzyme was significantly inhibited by simultaneous addition of both threonine and lysine, which is a typical feature of aspartate kinase III of B. subtilis. The enzyme was very unstable in 10 mM tris-HCl (pH 7.5) buffer, but was stabilized by addition of 500 mM ammonium sulfate. Although all the aspartate kinases so far investigated are oligomeric enzymes, this aspartate kinase was suggested to be a monomer.

[Changes in otoacoustic emission during the glycerol test in the ears of patients with Meniere's disease]

Monitoring of cochlear function is one proposed clinical application of otoacoustic emission (OAE). To determine the clinical utility of OAE in monitoring, we studied changes in OAE during the glycerol test used to diagnose endolymphatic hydrops. Transiently evoked OAE (TEOAE) and distortion product OAE (DPOAE) were measured before and 3 hours after oral administration of glycerol in 22 ears of patients with Meniere's disease. The positive result in the glycerol test was observed in 11 of 22 ears. TEOAE was recorded using a nonlinear click stimulus, and total echo power (TEP) of the whole response and filtered echo power (FEP) of its mid-frequency (1000-2000 Hz) component were used as TEOAE parameters. The growth functions of DPOAE were recorded at 3 F2 frequencies--1000, 1500, and 2000 Hz. Changes in the growth function were determined based on changes in 2 parameters--maximum level and detection threshold of DPOAE. When changes in these 4 parameters exceeded 2 standard deviations above mean test-retest variability determined from OAE data for 17 normal ears, they were considered significant. Significant changes indicating improved cochlear function in 4 OAE parameters or the appearance of OAE during the glycerol test were judged positive for OAE. Regardless of glycerol test results, positive findings were observed in both OAEs whenever a pure-tone threshold at 1000 or 2000 Hz improved. However, even in ears for which pure-tone thresholds at these frequencies did not improve, both OAEs frequently exhibited positive findings. In all ears with a positive result in the glycerol test, positive findings were observed in DPOAE, but not in TEOAE. Of the 2 parameters of TEOAE, FEP always exhibited a positive finding in ears with a positive TEP finding and FEP positivity was higher than that of TEP. In DPOAE, no cases showed a positive finding only at F2 = 2000 Hz, and DPOAE at F2 = 1000 Hz could not be detected in 4 ears due to high noise floor. Overall, positive findings were obtained in 14 ears (63.9%) for TEOAE and 20 ears (90.9%) for DPOAE. In only 1 ear were no positive findings observed in either OAE. The sensitivity of OAE measurement as a diagnostic test for endolymphatic hydrops was higher than that of pure-tone audiometry. Of the 2 OAEs, test sensitivity was much higher for DPOAE than for TEOAE. These results show that OAE measurement detects changes in cochlear function during the glycerol test more sensitively than pure-tone audiometry. They also suggest that FEP is a better indicator than TEP as a parameter of TEOAE, and that DPOAE measurement at F2 = 1000 and 1500 Hz is sufficient for practical clinical use. However, of the 2 OAEs, DPOAE was considered more appropriate than TEOAE for monitoring during the glycerol test because of its high sensitivity in detection of changes in cochlear function. In conclusion, clinical use of OAE, especially DPOAE, as a test complementary to pure-tone audiometry during the glycerol test is very useful and will improve the diagnosis of endolymphatic hydrops.

Evidence for the presence of DNA-binding proteins involved in regulation of the gene expression of indole-3-pyruvic acid decarboxylase, a key enzyme in indole-3-acetic acid biosynthesis in Azospirillum lipoferum FS

We isolated the ipdc gene coding for indole-3-pyruvic acid decarboxylase (IPDC), a key enzyme in the indole-3-pyruvic acid pathway for indole-3-acetic acid biosynthesis, in the plant growth-promoting rhizobacterium Azospirillum lipoferum FS. Gel mobility-shift assay showed the presence of two DNA-binding proteins that might be involved in regulation of the ipdc gene expression.

Isolation and characterization of the genes encoding a novel oxygenase component of angular dioxygenase from the gram-positive dibenzofuran-degrader Terrabacter sp. strain DBF63

A gram-positive bacterium Terrabacter sp. strain DBF63 is able to degrade dibenzofuran (DF) via initial dioxygenation by a novel angular dioxygenase. The dbfA1 and dbfA2 genes, which encode the large and small subunits of the dibenzofuran 4,4a-dioxygenase (DFDO), respectively, were isolated by a polymerase chain reaction-based method. DbfA1 and DbfA2 showed moderate homology to the large and small subunits of other ring-hydroxylating dioxygenases (less than 40%), respectively, and some motifs such as the Fe(II) binding site and the [2Fe-2S] cluster ligands were conserved in DbfA1. DFDO activity was confirmed in Escherichia coli cells containing the cloned dbfA1 and dbfA2 genes with the complementation of nonspecific ferredoxin and ferredoxin reductase component of E. coli. Under this condition, these cells exhibited angular dioxygenation of DF and dibenzo-p-dioxin, and monooxygenation of fluorene, but not angular dioxygenation of carbazole, xanthene, and phenoxathiin. Phylogenetic analysis revealed that DbfA1 formed a branch with recently reported large subunits of polycyclic aromatic hydrocarbon (PAH) dioxygenase from gram-positive bacteria but did not cluster with that of other angular dioxygenases, i.e., DxnA1 from Sphingomonas sp. strain RW1 [Armengaud, J., Happe, B., and Timmis, K. N. J. Bacteriol. 180, 3954-3966, 1998] and CarAa from Pseudomonas sp. strain CA10 [Sato, S., Nam, J.-W., Kasuga, K., Nojiri, H., Yamane, H., and Omori, T. J. Bacteriol. 179, 4850-4858, 1997].

A novel chordin-like protein inhibitor for bone morphogenetic proteins expressed preferentially in mesenchymal cell lineages

Chordin is a bone morphogenetic protein (BMP) inhibitor that has been identified as a factor dorsalizing the Xenopus embryo. A novel secreted protein, CHL (for chordin-like), with significant homology to chordin, was isolated from mouse bone marrow stromal cells. Injection of CHL RNA into Xenopus embryos induced a secondary axis. Recombinant CHL protein inhibited the BMP4-dependent differentiation of embryonic stem cells in vitro and interacted directly with BMPs, similar to chordin. However, CHL also weakly bound to TGFbetas. In situ hybridization revealed that the mouse CHL gene, located on the X chromosome, was expressed predominantly in mesenchyme-derived cell types: (1) the dermatome and limb bud mesenchyme and, later, the subdermal mesenchyme and the chondrocytes of the developing skeleton during embryogenesis and (2) a layer of fibroblasts/connective tissue cells in the gastrointestinal tract, the thick straight segments of kidney tubules, and the marrow stromal cells in adults. An exception was expression in the neural cells of the olfactory bulb and cerebellum. Interestingly, the spatiotemporal expression patterns of CHL were distinct from those of chordin in many areas examined. Thus, CHL may serve as an important BMP regulator for differentiating mesenchymal cells, especially during skeletogenesis, and for developing specific neurons.

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.

Expression pattern of the CsPK3 auxin-responsive protein kinase gene

We have previously cloned a cDNA of a putative serine/threonine protein kinase gene named CsPK3 from cucumber, the mRNA level of which was up-regulated by auxin and down-regulated by light irradiation. To examine the CsPK3 gene expression in detail, we cloned a genomic DNA of CsPK3 gene and made transgenic tobacco (Nicotiana tabacum L. cv. Petit Havana SR1) plants containing the fused CsPK3 promoter-beta-glucuronidase gene. The beta-glucuronidase expression was detected in the shoot apex, vascular tissues, and the outermost layer of cortex. The histological distribution of CsPK3 mRNA in cucumber seedlings was supported by in situ hybridization, where the positive signals were observed in similar tissues as those observed by beta-glucuronidase staining. The responsiveness of the CsPK3 gene to auxin and light was also confirmed for beta-glucuronidase activity. The pattern of beta-glucuronidase staining changed during the development of the tobacco seedlings. The results of our experiment showed that CsPK3 was expressed in a wide variety of tissues and cells in which the developmental and growth controls by auxin are suggested.

A physical map with yeast artificial chromosome (YAC) clones covering 63% of the 12 rice chromosomes

A new YAC (yeast artificial chromosome) physical map of the 12 rice chromosomes was constructed utilizing the latest molecular linkage map. The 1439 DNA markers on the rice genetic map selected a total of 1892 YACs from a YAC library. A total of 675 distinct YACs were assigned to specific chromosomal locations. In all chromosomes, 297 YAC contigs and 142 YAC islands were formed. The total physical length of these contigs and islands was estimated to 270 Mb which corresponds to approximately 63% of the entire rice genome (430 Mb). Because the physical length of each YAC contig has been measured, we could then estimate the physical distance between genetic markers more precisely than previously. In the course of constructing the new physical map, the DNA markers mapped at 0.0-cM intervals were ordered accurately and the presence of potentially duplicated regions among the chromosomes was detected. The physical map combined with the genetic map will form the basis for elucidation of the rice genome structure, map-based cloning of agronomically important genes, and genome sequencing.

New classification system for oxygenase components involved in ring-hydroxylating oxygenations

Batie et al. [Chemistry and Biochemistry of Flavoenzymes, 3, 543-556 (1991)] proposed a classification system for ring-hydroxylating oxygenases in which the oxygenases are grouped into three classes in terms of the number of constituent components and the nature of the redox centers. But in recent years, many ring-hydroxylating oxygenases have been newly identified and characterized, and found difficult to classify into these three classes. Typical examples are carbazole 1,9a-dioxygenase and 2-oxo-1,2-dihydroquinoline 8-monooxygenase, which have been classified into class III and class IB, respectively, from biochemical characteristics. However, a phylogenetic study showed that the terminal oxygenases of both are closely related to class IA. Because this discrepancy derived from counting all the components together, here we proposed a new scheme based on the homology of the amino acid sequences of the alpha subunits of the terminal oxygenase components. This new scheme strongly reflects the actual phylogenetic affiliation of the terminal oxygenase component. By comparing their sequences pairwise using the CLUSTAL W program, 54 oxygenase components were classified into 4 groups (groups I, II, III, and IV). While group I contains broad-range oxygenases sharing low homology, groups II, III, and IV contain some typical oxygenases: benzoate/toluate dioxygenases for group II, naphthalene/polycyclic aromatic hydrocarbon dioxygenases for group III, and benzene/toluene/biphenyl dioxygenases for group IV. Our new scheme is simple and powerful, since an oxygenase component can be nearly automatically grouped when the DNA sequence is available, and it fits very well with the phylogenetic affiliation.

Prostaglandin E(2) receptors, EP2 and EP4, differentially modulate TNF-alpha and IL-6 production induced by lipopolysaccharide in mouse peritoneal neutrophils

The expression and function of prostaglandin (PG) E(2) receptors were examined in mouse neutrophils exudated into the peritoneal cavity by casein treatment. Expressions of the EP2 and EP4 receptors were detected in neutrophils by Northern blot, but those of EP1 and EP3 receptors were not detected by RT-PCR. EP2-selective agonist, ONO-AE1-259, and EP4-selective agonist, ONO-AE1-329, stimulated cAMP formation in the cells. PGE(2) affected the TNF-alpha and IL-6 production in lipopolysaccharide (LPS)-treated neutrophils; it suppressed the TNF-alpha production and enhanced the IL-6 production. The PGE(2) effects were mimicked by dibutyryl cAMP. This is the first study of the enhancement of IL-6 production by cAMP-elevating reagents in neutrophils. Using neutrophils from EP2- and EP4-deficient mice in combination with EP2- and EP4-selective agonists, it was found that the augmentation of IL-6 was mediated mainly by the EP2 receptor and the suppression of TNF-alpha by the EP4 receptor and partially by the EP2 receptor. These findings indicate that casein-induced peritoneal neutrophils express Gs-coupled PGE(2) receptors, EP2 and EP4, which might differentially regulate the LPS-induced production of TNF-alpha and IL-6.

Positive and negative regulation of IL-12 receptor expression of naive CD4(+) T cells by CD28/CD152 co-stimulation

IL-12 is a critical cytokine for polarizing naive CD4(+) T cells toward Th1 subset. Therefore, it is important to elucidate the mechanism of IL-12R expression of naive CD4(+) T cells. In this report, we present evidence to show that expression of both IL-12Rbeta1 and beta2 mRNA is regulated by signals mediated through CD28 and CD152. Naive CD4(+) T cells stimulated with anti-CD3 alone neither expressed IL-12Rbeta2 mRNA nor bound detectable level of rIL-12, although they expressed a very low level of IL-12Rbeta1 mRNA when stimulated with a high dose of anti-CD3. Expression of IL-12Rbeta1 and beta2 mRNA was induced by the co-ligation of CD3 and CD28, and it was down-regulated by the ligation of CD152. CD28 ligation induced not only IL-12Rbeta1 and beta2 mRNA expression, but also enhanced IFN-gammaR to mediate up-regulation of IL-12R by IFN-gamma.

Identification of novel metabolites in the degradation of phenanthrene by Sphingomonas sp. strain P2

Sphingomonas sp. strain P2, which is capable of utilizing phenanthrene as a sole carbon and energy source, was isolated from petroleum-contaminated soil in Thailand. Gas chromatography-mass spectrometry and (1)H and (13)C nuclear magnetic resonance analyses revealed two novel metabolites from the phenanthrene degradation pathway. One was identified as 5,6-benzocoumarin, which was derived by dioxygenation at the 1- and 2-positions of phenanthrene, and the other was determined to be 1,5-dihydroxy-2-naphthoic acid. Other metabolites from phenanthrene degradation were identified as 7, 8-benzocoumarin, 1-hydroxy-2-naphthoic acid and coumarin. From these results, it is suggested that strain P2 can degrade phenanthrene via dioxygenation at both 1,2- and 3,4-positions followed by meta-cleavage.

Saccharide production from methanol by transposon 5 mutants derived from the extracellular polysaccharide-producing bacterium Methylobacillus sp. strain 12S

A CH3OH-utilizing bacterium that has the ability to produce extracellular polysaccharide (EPS) was isolated from a soil sample, and was identified as the obligate methylotroph Methylobacillus sp. strain 12S on the basis of its 16S rDNA sequence and growth-substrate specificity. The EPS produced by strain 12S was purified and the sugar composition was analysed by GC-MS and HPLC to reveal that the EPS was a heteropolymer composed of glucosyl, galactosyl, and mannosyl residues in the molar ratio 3:1:1. In order to produce mono- and/or oligosaccharides by single-step fermentation from CH3OH, stain 12S was mutagenized by transposon 5. Among eleven EPS-deficient mutants, three strains were found to accumulate significant amounts of reducing sugars in the media. The amounts of the reducing sugars produced by the mutants ( > ca. 700 mg glucose equivalent/l) were > 11-22 times higher than those produced by the wild-type strain (<ca. 60 mg glucose equivalent/l). The GC-MS analysis showed that all the mutants accumulated glucose, erythrose, threose and a disaccharide-like compound in the media.

Isolation and characterization of low-indole-3-acetic acid-producing mutants from Bradyrhizobium elkanii

We isolated 11 low-indole-3-acetic acid (IAA)-producing mutants of Bradyrhizobium elkanii by Tn5 mutagenesis. The amount of IAA produced by each mutant was 2.2-13.6% of that of the wild-type. It was found by resting cell reactions that the biosynthetic step to convert indole-3-pyruvic acid to indole-3-acetaldehyde was blocked in all the mutants.

A new class of biflavonoids: 2'-hydroxygenistein dimers from the roots of white lupin

Two novel isoflavonoid dimers presumably originating from 2'-hydroxygenistein, 5,7,4'-trihydroxycoumaranochroman-4-one-(3-->5"')-5",7",2"'4"'- tetrahydroxyisoflavone (1, lupinalbisone A) and 5,7,4'-trihydroxycoumaranochroman-4-one-(3-6")-5",7",2"',4"'-te trahydroxyisoflavone (2, lupinalbisone B) were isolated from the roots of Lupinus albus L., and their structures involving relative stereochemistry were elucidated by spectroscopic methods. Using horse radish peroxidase and 2'-hydroxygenistein (3) as the substrate revealed the formation of these dimers together with 5,7,4'-trihydroxycoumaronochromone (4, lupinalbin A). Dimerization of 3 caused a remarkable increase of antifungal activity.

Role of the rasGAP-associated docking protein p62(dok) in negative regulation of B cell receptor-mediated signaling

Antigenic stimulation of the B-cell receptor (BCR) is a central event in the immune response. In contrast, antigen bound to IgG negatively regulates signals from the BCR by cross-linking it to the inhibitory receptor FcgammaRIIB. Here we show that upon cross-linking of BCR or BCR with FcgammaRIIB, the rasGAP-associated protein p62(dok) is prominently tyrosine phosphorylated in a Lyn-dependent manner. Inactivation of the dok gene by homologous recombination has shown that upon BCR cross-linking, p62(dok) suppresses MAP kinase and is indispensable for FcgammaRIIB-mediated negative regulation of cell proliferation. We propose that p62(dok), a downstream target of many PTKs, plays a negative role in various signaling situations.

Cystine protects cochlear outer hair cells against glutamate toxicity

We previously reported that long-term exposure to glutamate (Glu) induced death of cochlear outer hair cells (OHCs). However, the mechanisms of OHC death induced by Glu were unclear. In the central nervous system, Glu is known to interfere with a cystine-Glu antiporter, leading to a decrease in cystine uptake and reducing the intracellular glutathione level. We therefore investigated the effect of cystine supplementation on degeneration of OHCs caused by long-term exposure to Glu. Supplementation of cystine significantly decreased the number of dying OHCs. These findings suggest that a cystine-Glu interaction may be involved in the mechanism of OHC degeneration caused by Glu.

A prokaryotic gene cluster involved in synthesis of lysine through the amino adipate pathway: a key to the evolution of amino acid biosynthesis

In previous studies we determined the nucleotide sequence of the gene cluster containing lys20, hacA (lys4A), hacB (lys4B), orfE, orfF, rimK, argC, and argB of Thermus thermophilus, an extremely thermophilic bacterium. In this study, we characterized the role of each gene in the cluster by gene disruption and examined auxotrophy in the disruptants. All disruptants except for the orfE disruption showed a lysine auxotrophic phenotype. This was surprising because this cluster consists of genes coding for unrelated proteins based on their names, which had been tentatively designated by homology analysis. Although the newly found pathway contains alpha-aminoadipic acid as a lysine biosynthetic intermediate, this pathway is not the same as the eukaryotic one. When each of the gene products was phylogenetically analyzed, we found that genes evolutionarily-related to the lysine biosynthetic genes in T. thermophilus were all present in a hyperthermophilic and anaerobic archaeon, Pyrococcus horikoshii, and formed a gene cluster in a manner similar to that in T. thermophilus. Furthermore, this gene cluster was analogous in part to the present leucine and arginine biosyntheses pathways. This lysine biosynthesis cluster is assumed to be one of the origins of lysine biosynthesis and could therefore become a key to the evolution of amino acid biosynthesis.

Cytochrome c redistribution in apoptosis of guinea pig vestibular hair cells

We examined the cellular location of cytochrome c in healthy and in streptomycin-damaged vestibular hair cells by immunohistochemistry. Staining for cytochrome c revealed an immunostain pattern that was consistent with a mitochondrial distribution of this enzyme in healthy hair cells, while in hair cells affected by aminoglycosides, a diffuse distribution in the cytoplasm was found together with apoptotic nuclear morphology. These findings suggest that redistribution of cytochrome c is involved in the pathway of apoptosis in vestibular hair cells induced by aminoglycosides.

Double high-dose chemotherapy supported by autologous transplantation of peripheral blood stem cells for treatment of an elderly patient with small-cell lung cancer

We report a 62-year-old male with extensive disease small-cell lung cancer (SCLC) who was successfully treated with double high-dose chemotherapy supported by autologous peripheral blood stem cell transplantation (auto-PBSCT). This patient achieved a partial response with 3 cycles of induction chemotherapy. After the peripheral blood stem cell mobilization, two cycles of high-dose ICE regimen (ifosfamide 3,000 mg/m2 at days 1 to 5, carboplatin 400 mg/m2 at days 1, 3, 5, and etoposide 500 mg/m2 at days 1, 3, 5) could be given with further regression of the tumor and acceptable toxicities. This successful case suggests the feasibility of double high-dose ICE with auto-PBSCT in elderly patients with SCLC.

Glutamate toxicity induced degeneration of outer hair cells with a temporal increase of nitric oxide production in the guinea pig cochlea

The aim of this study was to examine the roles of glutamate (GLU) toxicity and involvement of nitric oxide (NO) in the pathogenesis of cochlear degeneration. We examined guinea pig cochleae following chronic exposure to GLU. Trypan blue extrusion and transmission electron microscopy were performed to evaluate degeneration in the organ of Corti. In parallel, nitric oxide synthase (NOS) activity was demonstrated by histochemical staining of NADPH diapholase. GLU treatment caused time-dependent degeneration of outer hair cells (OHCs) in conjunction with a temporal increase of NOS activity in the organ of Corti. This suggests that GLU may be involved in OHC degeneration under toxic conditions, with NO production possibly playing a role in this process.

Effective stimulation for IL-12 p35 mRNA accumulation and bioactive IL-12 production of antigen-presenting cells interacted with Th cells

Bioactive IL-12 is composed of two subunits, p35 and p40. In the APC-Th cell interaction, p40 mRNA accumulation in APC was shown to be up-regulated by stimulation with CD40 ligand (CD40L) on Th cells. However, the CD40-CD40L interaction scarcely induced p35 mRNA accumulation in APC. In the present experiments, p35 mRNA accumulation was induced in splenic macrophages/dendritic cells by the interaction with paraformaldehyde-fixed Th1 cells in the presence of Ag, and the p35 mRNA accumulation was abrogated by the inclusion of anti-I-A in cultures to block TCR/MHC class II interaction. The accumulation was also induced by the stimulation with agonistic anti-I-A. These results indicate that the interaction of the MHC class II molecule with TCR evokes an activation signal for p35 mRNA accumulation in APC. Furthermore, the production of bioactive IL-12 in macrophages/dendritic cells stimulated with CD40L was enhanced by the inclusion of agonistic anti-I-A. The p35 mRNA accumulation and IL-12 production of macrophages/dendritic cells induced by stimulation with OVA-specific fixed Th1 clone expressing CD40L were also enhanced by adding OVA in cultures. These results indicate that the p35 mRNA accumulation induced by MHC class II stimulation plays a role in bioactive IL-12 production.

Involvement of nitric oxide in aminoglycoside vestibulotoxicity in guinea pigs

Involvement of nitric oxide (NO) has been reported in physiological and pathological conditions in the inner ear. Recently, the presence of nitric oxide synthase (NOS) was demonstrated in the vestibular epithelium. In this study we used nicotinamide adenine dinucleotide phosphate-diapholase staining to monitor NOS activity during degeneration of guinea pig vestibular epithelia affected by streptomycin. Increased NOS activity was observed in affected epithelia in a dose- and time-dependent manner and a NOS inhibitor could protect hair cells from apoptosis. Additionally, cycloheximide significantly reduced NOS activity and the occurrence of apoptosis. These findings suggest that NO is involved in the degenerative process of vestibular epithelia caused by aminoglycosides.

Aspergillus osteomyelitis in a child who has p67-phox-deficient chronic granulomatous disease

Here we describe Aspergillus osteomyelitis of the tibia in a 9-year-old boy who has an autosomal recessive form of chronic granulomatous disease (CGD). The patient showed a p67-phagocyte oxidase (phox) deficiency, which is rare type of CGD in Japan. The initial treatment which consisted of surgical debridement and antibiotic therapy with amphotericin B (AMPH), did not control the infection. Aspergillus fumigatus (A. fumigatus) pure isolated from drainage fluid and necrotic bone tissue demonstrated less susceptible to antifungal agents, including AMPH, fluconazole and flucytosine. Recombinant interferon gamma was then administrated, and it was effective in controlling the course of severe invasive aspergillosis. This report indicates the use of interferon gamma might be helpful in control for Aspergillus osteomyelitis of the tibia in a child with CGD demonstrated p67-phox deficiency refractory to conventional therapy with AMPH.

Diverse oxygenations catalyzed by carbazole 1,9a-dioxygenase from Pseudomonas sp. Strain CA10

Carbazole 1,9a-dioxygenase (CARDO) from Pseudomonas sp. strain CA10 is a multicomponent enzyme that catalyzes the angular dioxygenation of carbazole, dibenzofuran, and dibenzo-p-dioxin. It was revealed by gas chromatography-mass spectrometry and 1H and 13C nuclear magnetic resonance analyses that xanthene and phenoxathiin were converted to 2,2',3-trihydroxydiphenylmethane and 2,2',3-trihydroxydiphenyl sulfide, respectively. Thus, for xanthene and phenoxathiin, angular dioxygenation by CARDO occurred at the angular position adjacent to the oxygen atom to yield hetero ring-cleaved compounds. In addition to the angular dioxygenation, CARDO catalyzed the cis dihydroxylation of polycyclic aromatic hydrocarbons and biphenyl. Naphthalene and biphenyl were converted by CARDO to cis-1, 2-dihydroxy-1,2-dihydronaphthalene and cis-2,3-dihydroxy-2, 3-dihydrobiphenyl, respectively. On the other hand, CARDO also catalyzed the monooxygenation of sulfur heteroatoms in dibenzothiophene and of the benzylic methylenic group in fluorene to yield dibenzothiophene-5-oxide and 9-hydroxyfluorene, respectively. These results indicate that CARDO has a broad substrate range and can catalyze diverse oxygenation: angular dioxygenation, cis dihydroxylation, and monooxygenation. The diverse oxygenation catalyzed by CARDO for several aromatic compounds might reflect the differences in the binding of the substrates to the reaction center of CARDO.

Interaction between fibronectin and eosinophils in the growth of nasal polyps

OBJECTIVES

The aim of this study was to determine roles of fibronectin and eosinophils in the etiology of nasal polyposis.

STUDY DESIGN

We designed a cohort study of cases with nasal polyposis. Sampled nasal polyps were differentiated by their histopathologic characteristics, and compared by size and computed tomography (CT) stage.

METHODS

The size of nasal polyps was determined on the basis of the endoscopic findings, and the extent of sinusitis was evaluated by CT staging. Nasal polyp samples were taken from 82 patients during ethmoidectomy and differentiated by morphologic characteristics, infiltration cell types, or fibronectin positivity. Then their sizes and CT stages were compared. In addition, correlation among these histological characteristics was analyzed.

RESULTS

Nasal polyps showing edematous morphology, eosinophil infiltration, or fibronectin expression were significantly large in size. Concerning CT stages, only the infiltration cell type showed a significant difference. Significant correlation among edematous morphology, eosinophil infiltration, and fibronectin expression was also recognized.

CONCLUSIONS

These findings suggest that interaction between eosinophils and fibronectin may play a role in edema formation, which contributes to the growth of nasal polyps.

Loss of HLA haplotype in lung cancer cell lines: implications for immunosurveillance of altered HLA class I/II phenotypes in lung cancer

Loss of expression of HLA class I antigens has been demonstrated in a wide variety of tumors and is considered to be one of the mechanisms whereby tumors escape T-cell surveillance. Genomic DNA of MHC class I/II molecules in seven lung cancer cell lines was investigated and compared with that in peripheral blood mononuclear cells. In three cell lines, OU-LC-A1, OU-LC-A2, and OU-LC-AS1, a loss of HLA haplotype was observed. Aberrations of HLA class I/II in tumor cell lines should be considered when MHC-restricted phenomena in vitro models are assessed and clinical use of tumor vaccination in vivo is considered.

Epithelial-myoepithelial carcinoma: An unusual tumor of the paranasal sinus

A 65-year old woman presented with nasal obstruction and on examination was found to have a huge mass in the maxillary sinus. This was removed, and histological examination revealed a mixture of trabecular structures consisting of inner dark cells, outer clear cells and solid structures consisting of only clear cells. Immunohistochemical examination showed the clear cells to be positive for alpha-smooth muscle actin. Ultrastructural examination confirmed the myoepithelial cell origin. The characteristic morphological, immunohistochemical and ultrastructural features aided in the diagnosis of epithelial-myoepithelial carcinoma.

Clinical value of MRA analysis of the vertebrobasilar system in vertiginous patients

Vertebrobasilar haemodynamics correlate closely with syndromal vertigo. The aim of this study is to examine the clinical value of MRA for evaluation of vertebrobasilar haemodynamics in vertiginous patients. We examined 40 individuals (20 with vertebrobasilar insufficiency and 20 diagnosed with other vestibular disorders). MRA results were quantified on the basis of the severity of vascular stenosis in the major arteries of the vertebrobasilar system and we analysed the relationship of these results with otoneurological diagnoses, eye-tracking tests (ETT) and optokinetic nystagmus (OKN). MRA results correlated well with otoneurological diagnoses and ETT results. Consequently, MRA can be used as a screening examination to evaluate vertebrobasilar haemodynamics and ETT may be a sensitive functional parameter of vertebrobasilar insufficiency.

Induction of macrophage exudation in the inner ear by OK432 treatment

OK432, a heat- and penicillin-treated lyophilized powder of a low virulent Su strain of Streptococcus pyogenes, was injected into the perilymphatic space of guinea pigs in order to determine the kinetics of exudation of inflammatory cells into the cochlea over a 7-day period. OK432 induced exudation of many neutrophils and Asialo GM1-positive cells into the scala tympani. The numbers of these cells peaked on the first day after OK432 treatment, and then gradually decreased. Four days after treatment very few of either of these types of cells were observed in the scala tympani. Asialo GM1-positive cells were confirmed to be activated macrophages. In ears treated with physiological saline or with the additive included in OK432 in control studies, no notable changes in the inner ear were recognized. These findings suggest that the inner ear can undergo induction of macrophage rapidly exudation by OK432 treatment as has previously been observed for other organs.

Quantitative analysis of correlation between smooth pursuit and vertebrobasilar hemodynamics

The cerebellar arterial system is derived from the vertebrobasilar system. However, the relation between cerebellar function and vertebrobasilar hemodynamics remains poorly understood. In this study on patients with vertebrobasilar insufficiency symptoms we examined the relation between magnetic resonance angiography (MRA) abnormalities in the vertebrobasilar system and smooth pursuit function, which is a sensitive parameter of cerebellar function. MRA abnormality was quantitatively assessed on the basis of the severity of stenosis in the vertebral arteries and basilar artery, and on the visualization of the superior cerebellar arteries. Smooth pursuit dysfunction was quantified by the combined amplitude of spikes on an electronystagmograph. A significant correlation was found between MRA abnormality and smooth pursuit dysfunction. This suggests that smooth pursuit dysfunction is closely related to static factors of dysregulation of vertebrobasilar blood flow. Therefore, smooth pursuit can be valued as a sensitive parameter to dysfunction of vertebrobasilar blood flow.

Assessment of hair cell death using the dye extrusion method

We examined the usefulness of the dye extrusion method for assessing cochlear hair cell death in guinea pigs. Unilateral temporal bones were incubated in sterile Dulbecco modified Eagle's medium for 1-6 h and then perfused with PBS/0.3% trypan blue to determine hair cell viability. Cells with nuclei stained with trypan blue were assumed to have died. The contralateral temporal bones of each animal were incubated with the same medium for 1-6 h and examined by transmission electron microscopy (TEM). This method revealed that hair cell viability under these conditions was maintained for at most 3 h. After incubation for more than 3 h, hair cell injury began and increased. After 6 h incubation, TEM revealed apoptotic death of outer hair cells. The results with this method agreed with the TEM findings. The dye extrusion method is simple, easy and useful for screening hair cell death in the cochlea under pathological conditions.

Apoptotic cell death in Kikuchi's disease: a TEM study

The pathogenesis of Kikuchi's disease (Kikuchi-Fujimoto disease, histiocytic necrotizing lymphadenitis) remains unclear. However, some previous studies have suggested that a disorder in cellular immunity is responsible for this disease, and apoptotic cell death appears to be the principal finding in the histogenesis of this disease. In the present study, a lymph node from a female patient with Kikuchi's disease was examined by transmission electron microscopy (TEM). TEM revealed specific morphological features of apoptotic cells, such as nuclear chromatin condensation and fragmentation along the nuclear membrane with intact organelles, and the presence of histiocytes phagocytosing karyorrhectic debris (apoptotic bodies) in areas affected by Kikuchi's disease. Although neither the role nor the trigger of apoptosis in Kikuchi's disease has been clearly determined, our findings show that apoptotic cell death clearly plays a role in the pathogenesis of Kikuchi's disease.

Time-dependent response of vestibular hair cells of guinea pigs following high-dose applications of streptomycin

Apoptosis has been reported to occur in vestibular hair cells following aminoglycoside treatment and is suggested to play a predominant role in deletion of affected hair cells. However, the type of cell death occurring during an acute phase of vestibular damage following high-dose application of streptomycin has not yet been determined. Hence, in this study we examined the cell death mode of vestibular hair cells during the acute phase. The numbers of hair cell nuclei stained by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) method and residual hair cells were quantitatively analysed. Hoechst nuclear staining was used for analysis of the nuclear morphology of affected hair cells. TUNEL staining of hair cell nuclei and lost hair cells began to appear 6 h after streptomycin treatment and increased with more exposure time. Apoptotic nuclear features could also be found from 6 h after streptomycin treatment. These findings support the thesis that apoptosis is a predominant cell death mode in degeneration of vestibular hair cells due to streptomycin ototoxicity.