Protection against dextran sulfate sodium-induced colitis by microspheres of ellagic acid in rats

Ellagic acid (EA), a naturally occurring plant phenol, has the antioxidant and anti-inflammatory activities. In the present study, we examined the effect of EA contained in microspheres on the ulcerative colitis induced experimentally in rats by dextran sulfate sodium (DSS). Experimental colitis was induced in male Fisher 344 rats by daily treatment with 3% DSS solution in drinking water for 7 days. EA of microspheres (mcEA: 1 approximately 10 mg/kg as EA contents) was administered p.o. twice daily for 6 days. In a preliminary study, we found that these microsphere capsules, when administered p.o., are effectively dissolved in the proximal to the ileo-cecal junction and distributed to the terminal ileum and the colon. The ulceration area, colon length, and mucosal myeloperoxidase (MPO) activity as well as thiobarbituric acid-reactive substances (TBARS) were measured on 7th day after the onset of DSS treatment. The DSS treatment for 7 days caused severe mucosal lesions in the colon, accompanied with the increases of MPO activity and TBARS as well as the decreases of body weight gain and colon length. Administration of mcEA reduced the severity of DSS-induced colitis in a dose-dependent manner, and a significant effect was observed at 10 mg/kg, the ED50 being 2.3 mg/kg. This mcEA treatment also significantly mitigated changes in various biochemical parameters in the colonic mucosa induced by DSS. Although plain EA (without using microspheres) was also effective in reducing the severity of DSS-induced colitis, this effect was much less potent as compared with that of mcEA; the ED50 was about 15 times higher than that of mcEA. In addition, a significant effect on DSS-induced colitis was also obtained by intra-rectal administration of superoxide dismutase, an anti-oxidative agent. These results suggest that EA prevents the ulcerative colitis induced by DSS, probably by radical scavenging and/or anti-oxidative actions. The microspheres used in this study may be useful for delivering an orally administered drug specifically to the colon.

Less damaging effect of whisky in rat stomachs in comparison with pure ethanol. Role of ellagic acid, the nonalcoholic component

BACKGROUND/AIM

Ellagic acid (EA), one of the polyphenols that are abundantly contained in whisky as a nonalcoholic component, has antioxidant and anti-inflammatory activities. In the present study, we compared the action of whisky and pure ethanol on the rat gastric mucosa, and examined the role of EA in the less-damaging effect of whisky in the stomach.

METHODS

Under urethane anesthesia, a rat stomach was mounted in an ex vivo chamber, perfused with saline, and the transmucosal potential difference (PD) was measured before and after exposure to whisky (Yamazaki, Suntory) and ethanol (43%). In a separate study, the animals were given whisky or ethanol (1 ml, 43%) p.o. under unanesthetized conditions, killed 1 h later, and the gastric mucosa was examined for hemorrhagic lesions.

RESULTS

Both whisky and ethanol caused a PD reduction, resulting in damage in the stomach, but these responses were less marked in the case of whisky. Although the reduced PD recovered gradually after removal of ethanol, this process was significantly expedited by co-application of EA (80 microg/ml), the recovery rate being much the same as that observed after exposure to whisky. The less-damaging effect of whisky was confirmed in unanesthetized rats after p.o. administration of these agents. In addition, EA (1-30 mg/kg), administered p.o. together with absolute ethanol (99.9%), reduced the severity of gastric lesions induced by ethanol, in a dose-dependent manner, and the effect at 30 mg/kg was equivalent to that obtained by the whisky component containing several low- and high-molecular-weight polyphenols. EA had a scavenging action against both oxygen and hydroxyl radicals in vitro, the effect being equivalent to that of catechol or alpha-tocopherol.

CONCLUSION

These results suggest that whisky is less irritating to the gastric mucosa, as compared with pure ethanol, and this property of whisky may be explained by EA, one of polyphenols contained in whisky, and its radical scavenging action.

Intracellular cytokine profile of CD14 positive cells in patients with hematologic malignancies and solid tumors during hematologic recovery phase after intensive chemotherapy designed to mobilize peripheral blood stem cells

We studied intracellular cytokines in monocytes by flow cytometry from 28 patients with hematologic malignancies and solid tumors to analyze the role of monokines in the hematologic recovery phase for peripheral blood stem cell harvest. The patients were divided into three groups: the first group, A, had a documented infection; the second group, B, had fever of unknown origin; and the third group, C, was afebrile. We found an increase in intracellular IL-1alpha, IL-6, IL-8 and TNF-alpha positive monocytes as CD14 positive gated cells cultured with lipopolysaccharide in all groups, but no increase was found with medium only when cultured for 4 h. We also found an increase in intracellular IL-1a, IL-6, IL-8 and TNF-alpha positive monocytes cultured with autologous serum for 4 h, but only in group A. The rate of intracellular cytokine positive cells was higher in monocytes cultured with only autologous serum from group A patients compared to those cells from the other groups; the data concerning IL-1a, IL-6 and TNF-alpha reached statistical significance (P < 0.05). However, increasing intracellular cytokine levels in the control group of patients exhibiting only infectious disease were observed. Thus, it appear that pro-inflammatory intracellular cytokine levels in monocytes are only related to microbial infections.

Induction of MTG8-specific cytotoxic T-cell lines: MTG8 is probably a tumour antigen that is recognized by cytotoxic T cells in AML1-MTG8-fused gene-positive acute myelogenous leukaemia

Several reports have demonstrated the persistent detection of AML1-MTG8 fusion products, representing minimal residual disease (MRD), in patients with t(8;21) acute myelogenous leukaemia (AML) who are in long-term remission. It is probable that immune-mediated mechanisms that are able to suppress the expansion of MRD may result in the continuance of remission. It was previously shown that some t(8;21) AML patients had high anti-MTG8 antibody titres. MTG8 expression in normal adult tissues is limited to the brain or heart in which human leucocyte antigen (HLA) class I cell-surface antigens are either not or are only faintly detectable. We hypothesized that the overexpression of the MTG8 gene in t(8;21) AML cells could act as a possible tumour antigen, which might be able to induce the immune-mediated suppression of the expansion of MRD. We were able to induce HLA-A0201-restricted cytotoxic T-lymphocyte (CTL) lines against an MTG8 peptide (MTG8b amino acids 182-191) using monocyte-derived dendritic cells from a healthy donor. T-cell receptor (TCR)Valpha17, TCRVbeta14 and 15, and TCRJbeta2.1 and 2.3 are predominantly used in these CTL lines. Our data, which suggest that the MTG8 protein could be one of the tumour antigens recognized by CTLs, may be helpful in further investigations of TCR analysis in t(8;21) AML patients with HLA-A0201 who are in long-term remission.

Vaccination of a refractory essential monoclonal cryoglobulinemia patient with cryoglobulin-pulsed dendritic cells

We vaccinated a refractory essential monoclonal cryoglobulinemia patient with monocyte-derived DCs (Mo-DCs) pulsed with purified cryoglobulin as a tumor antigen. During the vaccinations, his acrocyanosis improved and we were able to reduce the number of hot baths used to treat his symptoms, with no side effects. Furthermore, cryoglobulin-specific proliferative responses were observed after the vaccination. As there was a recurrence of acrocyanosis after the final vaccination, vaccination with Mo-DCs pulsed with purified cryoglobulin would seem to be a useful treatment for refractory essential monoclonal cryoglobulinemia.

The enzyme that synthesizes tetrahydrobiopterin from 6-pyruvoyl-tetrahydropterin in the lemon mutant silkworm consists of two carbonyl reductases

Tetrahydrobiopterin plays an important role in the biosynthesis of certain neurotransmitters. Using DEAE-Sepharose FF column chromatography, we separated the enzyme that synthesizes tetrahydrobiopterin from 6-pyruvoyl-tetrahydropterin [which is different from sepiapterin reductase (EC 1.1.1.153)] in the lemon mutant of the silkworm Bombyx mori into two fractions, which were named carbonyl reductase I (CR I) and carbonyl reductase II (CR II). The CR I enzyme converted 6-pyruvoyl-tetrahydropterin to 6-lactoyl-tetrahydropterin, while CR II converted 6-pyruvoyl-tetrahydropterin to 1'-hydroxy-2'-oxopropyl-tetrahydropterin, both reactions occurring only in the presence of NADPH. Neither of the two carbonyl reductases alone was able to catalyze the conversion of 6-pyruvoyl-tetrahydropterin to tetrahydrobiopterin in the presence of NADPH. However, when CR I was mixed with CR II in the reaction mixture, 6-pyruvoyl-tetrahydropterin was reduced to tetrahydrobiopterin in the presence of NADPH. Moreover, CR I catalyzed the formation of tetrahydrobiopterin from 1'-hydroxy-2'-oxopropyl-tetrahydropterin, while CR II converted 6-lactoyl-tetrahydropterin to tetrahydrobiopterin, both reactions occurring only in the presence of NADPH. Our results suggest that there are two potential routes for formation of tetrahydrobiopterin from 6-pyruvoyl-tetrahydropterin in the lemon mutant silkworm. In the first route, 1'-hydroxy-2'-oxopropyl-tetrahydropterin is formed from 6-pyruvoyl-tetrahydropterin by CR II and then reduced to tetrahydrobiopterin by CR I, both reactions occurring only in the presence of NADPH. In the other route, 6-pyruvoyl-tetrahydropterin is reduced to 6-lactoyl-tetrahydropterin by CR I and then converted to tetrahydrobiopterin by CR II, both reactions occurring only in the presence of NADPH.

Structure and transcriptional control of the flagellar master operon of Salmonella typhimurium

The flhD and flhC genes constitute the flagellar master operon whose products are required for expression of all the remaining flagellar operons in Salmonella typhimurium. Here we report the molecular structure and in vivo and in vitro expression of the flhD operon. Nucleotide sequence analysis revealed that the upstream region of this operon contains the consensus sequence for the cAMP-CRP binding site. Primer extension analysis demonstrated six possible transcription start sites for this operon. They include CRP-dependent and CRP-repressible transcription start sites. The CRP-dependent transcription start site is located 203 bp upstream of the initiation codon of the flhD gene and preceded by the consensus sequences of the -10 and -35 regions of the sigma 70-dependent promoter. The putative cAMP-CRP binding site is located centered 70 bp upstream of this start site. The CRP-repressible transcription start site is located within this putative cAMP-CRP binding site. These two start sites were confirmed by in vitro transcription experiments using sigma 70-RNA polymerase with or without cAMP-CRP.

Nucleosides and nucleotides. 175. Structural requirements of the sugar moiety for the antitumor activities of new nucleoside antimetabolites, 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)cytosine and -uracil1

We previously designed 1-(3-C-ethynyl-beta-d-ribo-pentofuranosyl)uracil (EUrd) and its cytosine congener (ECyd) as potential multifunctional antitumor nucleoside antimetabolites. They showed potent and broad-spectrum antitumor activity against various human and mouse tumor cells in vitro and in vivo. To clarify the structure-activity relationship of the sugar moiety, various 3'-C-carbon-substituted analogues, such as 1-propynyl, 1-butynyl, ethenyl, ethyl, and cyclopropyl derivatives, of ECyd and EUrd were synthesized. We also prepared 3'-deoxy analogues and 3'-homologues of ECyd and EUrd with different configurations to determine the role of the 3'-hydroxyl group and the length between the 3'-carbon atom and the ethynyl group and a 2'-ethynyl derivative of ECyd to determine the spatial requirements of the ethynyl group. The in vitro tumor cell growth inhibitory activities of these nucleosides against mouse leukemic L1210 and human KB cells showed that ECyd and EUrd were the most potent inhibitors in the series, with IC50 values of 0.016 and 0.13 microM for L1210 cells and 0.028 and 0.029 microM for KB cells, respectively. Only 3'-C-1-propynyl and -ethenyl derivatives of ECyd showed greatly reduced cytotoxicity. We found that the cytotoxic activity of these nucleosides predominantly depended on their first phosphorylation by uridine/cytidine kinase.

Flagellar filament elongation can be impaired by mutations in the hook protein FlgE of Salmonella typhimurium: a possible role of the hook as a passage for the anti-sigma factor FlgM

Among motile revertants isolated from flagellar hook-deficient (flgE) mutants of Salmonella typhimurium, one produced only short flagellar filaments in L broth, despite the fact that flagellin itself has the ability to polymerize into long filaments in vitro. This pseudorevertant has an intragenic suppressor, resulting in a two-amino-acid substitution (Asp-Gln-->Ala-Arg) in the C-terminal region of the hook protein, FlgE. The flagellation of the pseudorevertant was greatly affected by the concentration of NaCl in the culture media: we observed no filaments in the absence of NaCl, short filaments in 1% NaCl and full-length filaments in 2% NaCl. Electron microscopy of osmotically shocked cells showed that the number of hook-basal bodies on cells was constant under various NaCl conditions. Furthermore, we found that the mutant hook was straight rather than curved. We monitored the cellular flagellin level of this pseudorevertant under various NaCl concentrations by immunoblotting. It was revealed that little flagellin was present under NaCl-free conditions in contrast with the ordinary amounts of flagellin present in 2% NaCl. As the expression of flagellin is regulated by competitive interaction of a sigma factor, FliA, and a corresponding anti-sigma factor, FlgM, we also observed the effect of NaCl on the secretion of FlgM. FlgM was secreted into the media in more than 1% NaCl but accumulated inside the cells in the absence of NaCl, indicating that the failure of secretion of FlgM in the absence of salt was the cause of the impaired elongation of filaments.

Vinconate, a cognitive enhancer, and PI turnover-phospholipase C systems in the brain

The molecular mechanisms for the stimulation of inositol 1-phosphate (IP1) formation by vinconate were investigated using preparations of rat brain. Vinconate (10(-8)-10(-3) M) dose-dependently inhibited the binding of [3H]quinuclidinyl benzilate ([3H]QNB) to muscarinic acetylcholine receptors and its IC50 value for [3H]QNB binding was 1.7 x 10(-5) M. The rightward shift of carbachol displacement curve of [3H]QNB binding by GTP (10(-4) M) was completely abolished by vinconate (10(-5) M). Carbachol (10(-8)-10(-2) M) increased [3H]IP1 formation in a dose-dependent manner and the carbachol-induced [3H]IP1 formation was significantly accentuated by vinconate (10(-5) M). The enhancement of [3H]IP1 accumulation by vinconate was inhibited by approximately 50% in the presence of atropine (10(-5) M), although phentolamine and ketanserin had no effects on the stimulatory effect of vinconate on [3H]IP1 formation. Vinconate showed no alteration in the binding of [3H]guanosine 5'-(beta, gamma-imino) triphosphate ([3H]Gpp(NH)p) to the crude synaptic membranes. The enhancement of phosphatidylinositol 4,5-biphosphate (PIP2)-specific phospholipase C (PLC) activity by GTP was unaffected in the presence of 10(-3) M vinconate, whereas vinconate alone dose-dependently enhanced the activities of both PIP2-specific and cytosolic PLC. These results suggest that vinconate may induce the facilitation of phosphatidylinositide (PI) turnover via the stimulation of muscarinic acetylcholine receptors, the enhancement of coupling between muscarinic acetylcholine receptors and GTP-binding protein, and the direct activations of PIP2-specific and cytosolic PLC.

Successful foscarnet therapy for mucocutaneous infection with herpes simplex virus in a recipient after unrelated bone marrow transplantation

A 36-year-old Japanese man who received an unrelated bone marrow transplant (BMT) developed severe mucocutaneous infection with herpes simplex virus (HSV) type 1 during oral acyclovir prophylaxis. The lesions progressed despite treatment with intravenous acyclovir and vidarabine. The HSV isolates were sensitive acyclovir, vidarabine and foscarnet in vitro, but peripheral CD3- or CD19-positive cells were barely detectable even 4 months after transplant. A 12-day course of treatment with foscarnet led to a rapid improvement. Foscarnet therapy should be considered for all severe HSV infections following BMT, regardless of whether or not the HSV isolates are sensitive to acyclovir.

Discovery of a new tetrahydrobiopterin-synthesizing enzyme in the lemon mutant of the silkworm Bombyx mori

A new tetrahydrobiopterin-synthesizing enzyme, which is different from sepiapterin reductase (EC 1.1.1.153), was discovered in the integument of the lemon mutant of the silkworm Bombyx mori. This enzyme converted 6-pyruvoyltetrahydropterin to tetrahydrobiopterin, an essential cofactor in the hydroxylation of aromatic amino acids, in the presence of NADPH. The reaction proceeded via 6-lactoyltetrahydropterin and 1'-hydroxy-2'-oxopropyltetrahydropterin as intermediates. The molecular mass of this enzyme was estimated to be 40 kDa. N-Acetylserotonin, a potent inhibitor of sepiapterin reductase, slightly inhibited the enzymatic reaction. In the presence of 0.5 mM N-acetylserotonin, the formation of tetrahydrobiopterin by sepiapterin reductase purified from the normal strain silkworm was completely inhibited. However, the formation of tetrahydrobiopterin by the enzyme purified from the lemon mutant was inhibited by only about 50%. These results suggest an alternative biosynthetic pathway to tetrahydrobiopterin.

Effect of vinconate, an indolonaphthyridine derivative, on dopamine and serotonin concentrations in dialysate from the striatum of freely moving rats: brain microdialysis studies

The effect of (+/-)-methyl 3-ethyl-2,3,3a, 4-tetrahydro-1H-indolo[3,2,1-de][1,5]naphthyridine -6-carboxylate monohydrochloride (vinconate), an indolonaphthyridine derivative, on dopamine and serotonin concentrations in dialysate from the striatum of freely moving rats was examined by brain microdialysis. Twenty-minute samples collected were used to determine dopamine and serotonin by high-performance liquid chromatography in a single run. The basal extracellular levels of dopamine and serotonin were 41.12 +/- 5.04 and 10.41 +/- 1.71 (fmol/20 min), respectively. Dopamine concentrations in dialysate were significantly increased after a single treatment with vinconate (50-200 mg/kg p.o.). Tetrodotoxin (10 microM) added into the dialysis perfusate decreased dopamine concentrations in dialysate and vinconate had no effect on dopamine concentrations in dialysate when administered after tetrodotoxin. The vinconate-induced increase in dialysate dopamine concentrations was significantly reduced by scopolamine (1 microM) and N0434 (1 microM), respectively. Moreover, daily treatment with vinconate (25 mg/kg p.o.) for 7 days resulted in enhanced dopamine and serotonin concentrations in dialysate induced by subsequent vinconate treatment. These findings suggest that vinconate administered systemically can enhance dialysate dopamine concentrations and this effect may be related to the muscarinic receptor and the dopamine D2 receptor. The present findings also suggest that repeated treatment with vinconate may augment these effects of vinconate on dopamine and serotonin concentrations in dialysate from the brain.

Chicken extract stimulates haemoglobin restoration in iron deficient rats

Chicken essence is widely used as a traditional remedy for several ailments including anaemia. To test this claim for objective evidence, a series of experiments was carried out in anaemic rats by supplementing iron deficient diets with either liquid or lyophilised essence, which contains mainly protein and peptides (83 mg/ml) and free amino acids (3.1 mg/ml), very little iron (1 microgram/ml), and no fat. Haemoglobin returned to normal significantly more rapidly in rats supplemented with ad libitum liquid BEC over a period of up to 27 days compared with controls fed only water in addition to the ad libitum iron deficient diet. Haemoglobin was also significantly increased after 1 week in animals fed ad libitum diets supplemented with lyophilised chicken essence than with controls fed the unsupplemented diet. The effect was greater with supplementation at the level of 0.2% than at 1% lyophilised essence. The results indicate that the effects were mediated by increased appetite and by enhanced availability of food iron. These studies provide objective evidence for the traditional belief that chicken essence remedies anaemia.

Negative regulation by fliD, fliS, and fliT of the export of the flagellum-specific anti-sigma factor, FlgM, in Salmonella typhimurium

The fliD operon of Salmonella typhimurium consists of three flagellar genes, fliD, fliS, and fliT, and is transcribed in this order. It has been shown that an fliD::Tn10 mutation causes an excess export of the flagellum-specific anti-sigma factor, FlgM, resulting in an overexpression of flagellar class 3 operons. In this study, using gene-disruption mutants in the individual genes in the fliD operon, we showed that mutations in any one of the genes in the operon enhanced both FlgM export and the expression of flagellar regulon. This indicates that all three genes in the operon are involved in the negative regulation of FlgM export.

Effect of vinconate on the extracellular levels of dopamine and its metabolites in the rat striatum: microdialysis studies

The effects of (+/-)-methyl-3-ethyl-2,3,3 alpha, 4-tetrahydro-1H- indolo[3,2,1-de][1,5]naphthyridine-6-carboxylate hydrochloride (vinconate), an indolonaphthyridine derivative, on the extracellular levels of dopamine and its metabolites in the rat striatum were examined using brain microdialysis. Single administration of vinconate (10, 100 mg/kg i.p.) increased the extracellular level of dopamine and its metabolites. This enhancing effect of vinconate was antagonized by scopolamine (10 microM), a muscarinic receptor antagonist, which was added to the perfusate from 30 min before vinconate treatment. These findings suggest that vinconate, even when systemically administered, enhances the endogenous release of dopamine in the striatum, probably via the stimulation of presynaptic muscarinic receptors.

Functional analysis of the flagellar genes in the fliD operon of Salmonella typhimurium

The fliD genes of Salmonella typhimurium and Escherichia coli encode the filament-cap protein of the flagellar apparatus, which facilitates the polymerization of endogenous flagellin at the tips of the growing filaments. Previous sequence analysis of this operon in both organisms has revealed that the fliD gene constitutes an operon together with two additional genes, fliS and fliT. Based on the gene-disruption experiment in E. coli, both the fliS and fliT genes have been postulated to be necessary for flagellation. In the present study, we constructed S. typhimurium mutants in which either fliS or fliT on the chromosome was specifically disrupted. Both mutants were found to produce functional flagella, indicating that these genes are dispensable for motility development in S. typhimurium. However, flagellar filaments produced by the fliS mutant were much shorter than those produced by the wild-type strain. This indicates that the fliS mutation affects the elongation step of filament assembly. The excretion efficiency of flagellin was examined in the fliD-mutant background, where the exported flagellin molecules cannot assemble onto the hooks, resulting in their excretion into the culture media. We found that the amount of flagellin excreted was much reduced by the fliS mutation. Based on these results, we conclude that FliS facilitates the export of flagellin through the flagellum-specific export pathway.

Molecular characterization of the Salmonella typhimurium flhB operon and its protein products

The flhB and flhA genes constitute an operon called flhB operon on the Salmonella typhimurium chromosome. Their gene products are required for formation of the rod structure of flagellar apparatus. Furthermore, several lines of evidence suggest that they, together with FliI and FliH, may constitute the export apparatus of flagellin, the component protein of flagellar filament. In this study, we determined the nucleotide sequence of the entire flhB operon from S. typhimurium. It was shown that the flhB and flhA genes encode highly hydrophobic polypeptides with calculated molecular masses of 42,322 and 74,848 Da, respectively. Both proteins have several potential membrane-spanning segments, suggesting that they may be integral membrane proteins. The flhB operon was found to contain an additional open reading frame capable of encoding a polypeptide with a calculated molecular mass of 14,073 Da. We designated this open reading frame flhE. The N-terminal 16 amino acids of FlhE displays a feature of a typical signal sequence. A maxicell labeling experiment enabled us to identify the precursor and mature forms of the flhE gene products. Insertion of a kanamycin-resistant gene cartridge into the chromosomal flhE gene did not affect the motility of the cells, indicating that the flhE gene is not essential for flagellar formation and function. We have overproduced and purified N-terminally truncated FlhB and FlhA proteins and raised antibodies against them. By use of these antibodies, localization of the FlhB and FlhA proteins was analyzed by Western blotting (immunoblotting) with the fractionated cell extracts. The results obtained indicated that both proteins are localized in the cytoplasmic membrane.

Genetic and molecular analyses of the interaction between the flagellum-specific sigma and anti-sigma factors in Salmonella typhimurium

More than 50 genes are required for flagellar formation and function in Salmonella typhimurium. According to the cascade model of flagellar regulon, the flagellar operons are divided into three classes, 1, 2, and 3, with respect to transcriptional hierarchy. FliA is an alternative sigma factor specific for transcription of the class 3 operons, while FlgM is an anti-sigma factor which binds to FliA and prevents its association with RNA polymerase core enzyme. In the present study, we isolated a number of fliA mutants in which the altered FliA proteins become insensitive to inhibition by FlgM. Sequence analysis of their mutation sites revealed that most of them caused the amino acid substitutions in region 4 of the conserved amino acid sequences of sigma factors which lies near the C-terminal end of FliA. Using a set of fliA deletion mutants in a high-expression plasmid, we demonstrated that polypeptides containing the C-terminal portion of FliA could titrate the intracellular FlgM protein resulting in derepression of the class 3 operons. This result indicates that the C-terminal region of FliA contains the FlgM-binding domain. This was confirmed by a chemical cross-linking experiment with FlgM and truncated FliA proteins.

Identification of ommin in the integument of the silkworm, Bombyx mori

An ommin was isolated from the integument of the quail mutant of the silkworm, Bombyx mori, using column chromatography on SP-Sephadex and cellulose powder. As a standard, ommin was isolated from diapause eggs of the normal silkworm. The red pigment from the larval integument of quail mutants was identical to the standard compound with respect to absorption spectrum, infrared spectrum and RF values in thin-layer chromatography (TLC). After acid hydrolysis of the pigment, 3-hydroxykynurenine was detected by TLC. This is the first report of an ommin in a lepidopteran larval integument.

Role of the FliA-FlgM regulatory system on the transcriptional control of the flagellar regulon and flagellar formation in Salmonella typhimurium

In the flagellar regulon of Salmonella typhimurium, the flagellar operons are divided into three classes, 1, 2, and 3, with respect to transcriptional hierarchy. The class 2 operons are controlled positively by the class 1 genes, flhD and flhC. The class 3 operons are controlled positively by fliA and negatively by flgM. It has been shown that FliA is a sigma factor specific for class 3, whereas FlgM is an anti-sigma factor which binds FliA to prevent its association with RNA polymerase core enzyme. Therefore, the FliA-FlgM regulatory system has been believed to control specifically the class 3 operons. In the present study, we showed that the flgM mutation enhanced the expression of class 2 by more than fivefold. When a fliA mutation was present simultaneously, this enhancement was not observed. These results indicate that the FliA-FlgM regulatory system is involved not only in the expression of class 3 but also in that of class 2. However, though neither flhD nor flhC mutants could express the class 2 operons, the fliA mutants permitted the basal-level expression of those operons. Therefore, FlhD and FlhC are indispensable for the expression of class 2, whereas FliA is required only for its enhancement in the FlgM-depletion condition. Furthermore, we showed that the flgM mutation resulted in a two- to threefold increase in flagellar number. On the basis of these results, we propose that the relative concentration of FliA and FlgM may play an important role in the determination of flagellar numbers produced by a single cell.

Sequence analysis of the flgA gene and its adjacent region in Salmonella typhimurium, and identification of another flagellar gene, flgN

The flagellar genes flgA and flgM are located at the terminus of the region-I flagellar gene cluster on the chromosome of Salmonella typhimurium. The flgA gene is involved in P-ring formation of the flagellar basal body, whereas flgM encodes the anti-sigma factor which acts as a negative regulator of the flagellar regulon. The nucleotide sequence of the DNA fragment containing these flagellar genes and the adjacent region was determined. The flgA gene was found to encode a 219-amino-acid (aa) protein of 23,556 Da. The N-terminal region of FlgA has the characteristics of a typical signal sequence, suggesting that FlgA may function in the periplasmic space where P-ring assembly takes place. The flgM gene was found to constitute an operon together with an ORF which encodes a 140-aa protein of 15,899 Da. A gene disruption mutant was constructed by inserting a cat gene cartridge into the ORF on the chromosome. This mutant showed only weak motility, indicating that the product of the ORF is involved in flagellar formation. Therefore, this ORF was designated as flgN. Electron microscopic observation revealed that most of the flagellar structures produced by the flgN mutant are hook-basal body complexes lacking the filament portions. Based on these results, we concluded that the flgN product is required for the efficient initiation of filament assembly.

FlgD is a scaffolding protein needed for flagellar hook assembly in Salmonella typhimurium

FlgD is known to be absolutely required for hook assembly, yet it has not been detected in the mature flagellum. We have overproduced and purified FlgD and raised an antibody against it. By using this antibody, we have detected FlgD in substantial amounts in isolated basal bodies from flgA, flgE, flgH, flgI, flgK, and fliK mutants, in much smaller amounts in those from the wild type and flgL, fliA, fliC, fliD, and fliE mutants, and not at all in those from flgB, flgD, flgG, and flgJ mutants. In terms of the morphological assembly pathway, these results indicate that FlgD is first added to the structure when the rod is completed and is discarded when the hook, having reached its mature length, has the first of the hook-filament junction proteins, FlgK, added to its tip. Immunoelectron microscopy established that FlgD initially is located at the distal end of the rod and eventually is located at the distal end of the hook. Thus, it appears to act as a hook-capping protein to enable assembly of hook protein subunits, much as another flagellar protein, FliD, does for the flagellin subunits of the filament. However, whereas FliD is associated with the filament tip indefinitely, FlgD is only transiently associated with the hook tip; i.e., it acts as a scaffolding protein. When FlgD was added to the culture medium of a flgD mutant, cells gained motility; thus, although the hook cap is normally added endogenously, it can be added exogenously. When culture media were analyzed for the presence of hook protein, it was found only with the flgD mutant and, in smaller amounts, the fliK (polyhook) mutant. Thus, although FlgD is needed for assembly of hook protein, it is not needed for its export.

Blister formation on the thumb following the second intravenous regional reserpine in the hand. Case report

BACKGROUND AND OBJECTIVES

Local, not systemic, complications associated with intravenous regional sympathetic block (IVRS) are very rare. The authors report the complication that occurred in a 70-year-old man who sustained an injury of the left thumb.

METHODS

The second IVRS using reserpine and lidocaine, 1 week after the first IVRS, was performed for pain relief.

RESULTS

About 1 hour after the operation, an entirely localized blister developed in the dorsolateral aspect of the thumb. The palmar side appeared viable 2 weeks after the operation, which guaranteed intact survival of the thumb, but 2 months later the patient reported that he had the thumb amputated at an outside hospital.

CONCLUSIONS

When IVRS is applied to the extremities with compromised vasculature, or with an altered neuroanatomy, unpredictable and counterproductive mishaps may occur.