Activity-dependent reorganization of local circuitry in the developing visceral sensory system

Neural activity during critical periods could fine-tune functional synaptic connections. N-methyl-d-aspartate (NMDA) receptor activation is critically implicated in this process and blockade leads to disruption of normal circuit formation. This phenomenon has been well investigated in several neural systems including the somatosensory system, but not yet evidenced in the visceral sensory system. Ultrastructural analysis of GABAergic synapses and electrophysiological analysis of inhibitory and excitatory postsynaptic currents of the rat caudal nucleus tractus solitarii (NTS) cells revealed that developmental changes in the synaptic organizations were blocked by MK-801, an NMDA receptor antagonist, when administered at postnatal days 5-8, a presumed critical period for the visceral sensory system. Normal synapse reorganization during postnatal development dictates undifferentiated neonatal caudal NTS neurons in terms of synaptic input patterns measured by electron microscopy and electrophysiology into two cell groups: small and large cells under far stronger excitatory and inhibitory influence, respectively. Blockade by MK-801 during the critical period might leave adult neurons wired in the undifferentiated synaptic networks, possibly preventing synapse elimination and subsequent stabilization of the proper wiring.

Formation and relaxation of two-dimensional vortex crystals in a magnetized pure-electron plasma

Systematic examinations are carried out experimentally about the contribution of background vorticity distributions (BGVD's) to the spontaneous formation and decay of ordered arrays (vortex crystals) composed of strong vortices (clumps) by using a pure-electron plasma. It is found that the BGVD level needs to be higher for an increasing number of clumps to form vortex crystals and that the number of the clumps constituting the crystal decreases in time as proportional to gamma lnt in contrast to proportional to t (-xi) with xi approximately 1 as accepted well in turbulence models. The decay rate gamma increases with the BGVD level. The observed configurations of the clumps cover the theoretically predicted catalogue of vortex arrays in superfluid helium, suggesting a possible relaxation path of the crystal states.

Quantitative evaluation of adhesion of lactobacilli isolated from human intestinal tissues to human colonic mucin using surface plasmon resonance (BIACORE assay)

AIMS

To isolate lactobacilli from the mucus layer of the human intestine and evaluate their adhesion abilities using a BIACORE assay.

METHODS AND RESULTS

Thirty strains of lactobacilli were isolated from the mucus layer of normal human intestinal tissues using conventional plate culture. The strains were identified using homology comparisons of the 16S rDNA sequence to databases as Lactobacillus salivarius (26%), Lactobacillus fermentum (13%), Lactobacillus gasseri (10%), Lactobacillus paracasei (7%), Lactobacillus casei (3%), Lactobacillus mucosae (3%) and Lactobacillus plantarum (3%). Lactobacillus plantarum LA 318 shows the highest adhesion to human colonic mucin (HCM) using the BIACORE assay at 115.30 +/- 12.37 resonance unit (RU). The adhesion of cell wall surface proteins from strain LA 318 was significantly higher to HCM than to bovine serum albumin (BSA; P < 0.05).

CONCLUSIONS

We isolated 30 strains of lactobacilli. Lactobacillus salivarius was the predominant species of lactobacilli isolated in this study. The adhesion of strain LA 318 isolated from human transverse colon to its mucin was shown. The adhesion could be mediated by lectin-like components on the bacterial cell surface.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first study where lactobacilli were isolated from human intestinal tissues and shown to adhere to HCM.

The association of DNA repair gene polymorphisms with the development and progression of renal cell carcinoma

BACKGROUND

DNA repair enzymes repair some of the DNA damage associated with risk factors for renal cell carcinoma (RCC), including smoking. DNA repair gene polymorphisms modulate the repair capacity and might influence individual risk and progression of RCC. We examined associations between functional polymorphisms and risk, clinicopathologic characteristics and survival of RCC.

PATIENTS AND METHODS

The study groups comprised 215 RCC patients and 215 age- and gender-matched healthy controls. Polymorphisms in xeroderma pigmentosum complementation groups C, D and G and X-ray repair cross-complementing groups 1 and 3 genes were genotyped.

RESULTS

No significant differences in DNA repair genotype were observed between RCC cases and controls. In all patients, however, greater numbers (> or =3) of total variant alleles in all DNA repair genes studied were associated with less frequent venous extension (P = 0.0079). In smokers, some genotypes were associated with characteristics of RCC (Ps < or = 0.0067) and smokers with greater numbers of total variant alleles had improved overall survival (P = 0.040).

CONCLUSION

These results suggest that DNA repair gene polymorphisms may not influence RCC susceptibility, but that some of them may influence RCC progression, especially in smokers, possibly due to altered DNA repair capacity by these polymorphisms.

Turbulent cascade in vortex dynamics of magnetized pure electron plasmas

Elementary processes in free-decaying two-dimensional (2D) turbulence are examined by extensive analyses of fine structures in the density distribution of a magnetized pure electron plasma that is linearly unstable with the initial ring-shaped profile, deforms nonlinearly into patches of vortices, and relaxes into a single-peaked stable distribution via successive mergers among the patches. The stochastic dynamics of the decreasing number of vortices in the real space correspond to the time evolution of energy spectra E(k) in the wave number (k) space that the energy transfers down to lower k while the upward-spreading tails of the spectra fit to the power-law (proportional k(-alpha)) with alpha > 3. The transfer rates, epsilon(k) and eta(k) in energy and enstrophy spaces, evaluated from the time-resolved k -spectra demonstrate characteristic features of the 2D turbulence, i.e., epsilon(k) is negative and deepest below the k(inj) corresponding to the size of the first-generated patches, and eta(k) increases from zero to a constant value at k > k(inj). By averaging the time-dependent spectra of E(k), epsilon(k), and eta(k), constructions are carried out for the spectra in a stationary turbulence that is sustained by the continuous generation of vortices due to the instability and dissipation at high k. The spectra are qualitatively consistent with the 2D turbulence theory with discrepancies including that alpha approximately 4.4 and that the enstrophy transfer rate is almost zero around k = k(inj) reflecting the contribution from the coherent vortices.

Inhibition of Listeria monocytogenes by freeze-dried piscicocin CS526 fermentate in food

AIMS

The effectiveness of freeze-dried powder, fermented with bacteriocin producing Carnobacterium piscicola CS526, was evaluated for the inhibition of Listeria monocytogenes in a food model.

METHODS AND RESULTS

A 10% solution of milk whey powder was fermented with a bacteriocinogenic C. piscicola CS526 Bac(+) or its nonbacteriocinogenic mutant strain CS526 Bac(-) at 30 degrees C for 12 h and freeze-dried. The freeze-dried piscicocin CS526 Bac(+) fermentate exhibited strong anti-listerial activity even at a concentration of 1% (w/v) in sterile water (pH 7), but the piscicocin CS526 Bac(-) fermentate and nonfermented whey powder had no anti-listerial activity. In the presence of 10% piscicocin CS526 Bac(+) fermentate, L. monocytogenes in ground meat rapidly decreased from 10(5) CFU g(-1) to less than the detection limit (3.0 x 10(3) CFU g(-1)) within 5 and 1 days at 4 and 12 degrees C, and was bacteriostatically inhibited for 25 and 4 days at 4 and 12 degrees C respectively. Furthermore, this inhibitory effect was enhanced at lower temperatures.

CONCLUSIONS

Piscicocin CS526 Bac(+) fermentate was effective for the control of L. monocytogenes in a food model at refrigeration temperatures.

SIGNIFICANCE AND IMPACT OF THE STUDY

A freeze-dried bioactive piscicocin CS526 Bac(+) powder can be a powerful tool to ensure food safety against L. monocytogenes contamination in refrigerated foods such as ready-to-eat products.

Prescriptions for optimizing intensities of short-lived RIBs at ISOL based research facilities

In order to generate useful intensities of short-lived radioactive species at Isotope Separator On-Line (ISOL) based research facilities, species of interest must be diffused from the interior of the production target-material, effusively transported to an ion source, ionized, extracted, mass-analyzed, and accelerated to research energies in times commensurate with their lifetimes. The intensities at such facilities are principally limited by decay losses associated with times required for diffusion-release from target materials and transport from the target to the ion source and by the maximum permissible primary beam power depositional density that can be tolerated without deleteriously affecting target integrity or ion source efficiency. Consequently, it is imperative to minimize delay times associated with the independent diffusion and effusive-flow processes by choosing small dimensioned (short-diffusion length) highly refractory target materials and formatting them in highly permeable mechanically and thermally robust structures that can withstand high-power beam irradiation for extended periods of time. This article provides basic information on methods, procedures and principles for selecting target materials; for designing fast diffusion-release targets; for designing fast effusive-flow vapor transport systems; and introduces methods for controlling target temperatures as required for optimizing intensities of short-lived radioactive ion beams at ISOL based research facilities.

β-Glucosidase inhibitory activities of phenylpropanoid glycosides, vanicoside A and B from Polygonum sachalinense rhizome

The phenylpropanoid glycosides, vanicoside A and B, isolated from rhizomes of giant knotweed (Polygonum sachalinense) showed beta-glucosidase inhibitory activity, with IC(50) values of 59.8 and 48.3 mug/ml (59.9 and 50.5 muM), respectively. In contrast, p-coumaric acid and ferulic acid, corresponding to phenylpropanoyl moieties of vanicosides, exhibited very little inhibition.

Dynamical behavior of the motions associated with the nonlinear periodic regime in a laboratory plasma subject to delayed feedback

Time-delayed feedback is applied to the motions associated with the nonlinear periodic regime generated due to current-driven ion acoustic instability; this is a typical instability in a laboratory plasma, and the dynamical behavior is experimentally investigated using delayed feedback. A time-delayed autosynchronization method is applied. When delayed feedback is applied to the nonlinear periodic orbit, the periodic state changes to various motions depending on the control parameters, namely, the arbitrary time delay and the proportionality constant. Lyapunov exponents are calculated in order to examine the dynamical behavior.

Synthesis and cancer antiproliferative activity of new histone deacetylase inhibitors: hydrophilic hydroxamates and 2-aminobenzamide-containing derivatives

New series histone deacetylase inhibitors comprising a hydroxamic acid or 2-aminobenzamide group as a zinc-chelating function were synthesized and evaluated for antiproliferative activities against a panel of human cancer cells. The 2-aminobenzamide series inhibitors generally had the potency in cell growth inhibitions comparable to that of MS-275. Among them, the compound having a (3,4-difluorobenzyl)(2-hydroxyethyl)amino group at one end and a 2-aminobenzamide group at the other of molecule showed the most promising profile as an anticancer drug candidate, since it had a comparatively low toxicity as did MS-275 against a normal fibroblast cell CCD-1059SK. Additionally, the derivative exhibited a high recovery in human plasma stability test.

Turbo short tau inversion recovery imaging for metastatic node screening in patients with head and neck cancer

BACKGROUND AND PURPOSE

A rapid and sensitive MR imaging technique would be beneficial for screening of metastatic nodes in the neck. We preliminarily evaluated the coronal MR imaging with a turbo short tau inversion recovery (STIR) sequence for that purpose.

METHODS

The coronal turbo STIR imaging (repetition time [TR]/echo time [TE]/inversion time [TI] = 3850 ms/20 or 80 ms/180 ms) and axial fat-suppressed spectral presaturation with inversion recovery (SPIR) T2-weighted imaging (fsT2WI) (TR/TE = 3500 ms/80 ms) were performed on 29 patients with head and neck cancer. We obtained coronal turbo STIR images and axial fsT2WI of the necks. The section thickness, intersection gap, matrix size, and field of view were the same in both techniques. The diagnostic ability for metastatic nodes was assessed at each neck level by using various cutoff size criteria. The nodal involvement was confirmed by histologic examination.

RESULTS

The image acquisition time for the whole neck by coronal turbo STIR and axial fsT2WI techniques was approximately 2 minutes and 4 minutes, respectively. When the size criteria (cutoff sizes of short axis diameter were 8 mm at level I and 5 mm at levels II and III) were used, the STIR imaging yielded compromised diagnostic ability having 100% sensitivity and 100% negative predictive value (NPV). fsT2WI technique yielded 100 sensitivity and 100% NPV by using cutoff sizes of 6 mm at levels I and II and 5 mm at level III.

CONCLUSION

Coronal STIR imaging provided a rapid screening technique for cervical metastatic nodes and could be a diagnostic tool before detailed MR studies of the neck.

A new infiltration method for coating highly permeable matrices with compound materials for high-power isotope-separator-on-line production target applications

A new infiltration coating method has been conceived for uniform and controlled thickness deposition of target materials onto highly permeable, complex-structure matrices to form short-diffusion-length isotope-separator-on-line (ISOL) production targets for radioactive ion beam research applications. In this report, the infiltration technique is described in detail and the universal character of the technique illustrated in the form of SEMs of several metal-carbide, metal-oxide and metal-sulfide targets for potential use at present or future radioactive ion beam research facilities.

Mode of action of piscicocin CS526 produced by Carnobacterium piscicola CS526

AIMS

Piscicocin CS526 is a unique class IIa bacteriocin produced by Carnobacterium piscicola CS526. The mode of action against the sensitive strain Listeria monocytogenes IID581 was evaluated.

METHODS AND RESULTS

Piscicocin CS526 was adsorbed on both sensitive and insensitive gram-positive and gram-negative bacterial cells. Treatment of L. monocytogenes cells with trypsin, lipase and Triton X-100 did not reduce subsequent adsorption of piscicocin CS526. The activity of piscicocin CS526 against L. monocytogenes cells was bactericidal rather than bacteriostatic, but did not cause bacteriolysis. Piscicocin CS526 induced the efflux of K+ ions from the target cells which cause dissipation of the transmembrane potential (DeltaPsi) of the cell membrane. Moreover, after exposure to piscicocin CS526, intracellular adenosine 5'-triphosphate (ATP) level of the target cells rapidly reduced without leakage of ATP from the cells, indicating that ATP depletion occurred in the cells.

CONCLUSIONS

Pore formation by piscicocin CS526 caused a rapid efflux of small molecules such as K+ from the indicator cells and dissipation of proton motive force (PMF), which lead to the cell death.

SIGNIFICANCE AND IMPACT OF THE STUDY

Molecular mechanism of action of piscicocin CS526 is very similar to that of other pediocin-like bacteriocins, although piscicocin CS526 possesses a unique N-terminal sequence in which Val is substituted for by Leu in the amino acid at position 7.

Purification and characterization of pertucin produced by Pseudomonas pertucinogena

Pertucin, a bacteriocin active against phase I organisms of Bordetella pertussis, was extracted from Pseudomonas pertucinogena, strain 190 or 6627, by freezing and thawing of bacteria-free agar medium and was purified by ammonium sulfate fractionation, dialysis, zinc chloride precipitation, and polyacrylamide gel electrophoresis. The specific activity of purified pertucin was approximately 80 times that of the crude extract. The purified pertucin preparation was homogeneous on ultracentrifugal analysis and polyacrylamide gel electrophoresis, and was found to be composed of protein (80%) and carbohydrate (20%), the latter assumed not to be bound covalently to the protein. Neither nucleic acids nor lipids were demonstrated. N-terminal analysis by dansylation revealed only methionine in strain 190 and only glycine in strain 6627. The isoelectric point was found to be 4.8, and the molecular weight was estimated to be 31,500. Amino acid analysis of the protein moiety demonstrated that it contained all of the common amino acids with somewhat more of the hydrophilic amino acids. With respect to thermostability, pH stability, and effects of metal ions and various buffers, pertucin behaves like a protein and is stable in 0.05 M tris(hydroxymethyl)aminomethane buffer, pH 8.0, containing 0.01 M Ca(2+).

Melting and heating of two-dimensional Coulomb clusters in dusty plasmas

The heating and melting of two-dimensional dust clusters with one additional particle in the lower layer has been investigated experimentally in a gas discharge. The full dynamical properties of the system during the entire phase transition were determined in terms of the spectral power densities of the crystal modes. A two-step melting transition is identified when the gas pressure in the discharge is reduced: first, a sudden increase of the dust temperature takes place due to an instability of the lower-layer particle resulting in a hot crystalline state of the cluster, and second, the actual transition into a fluid state is observed at a decisively lower gas pressure.

Effect of cardiopulmonary bypass on pulmonary clearance of adrenomedullin in humans

BACKGROUND

Adrenomedullin is a potent vasodilatory peptide and its plasma concentration increases after cardiopulmonary bypass. We analyzed the contribution of the lung to the disposition of adrenomedullin before and after cardiopulmonary bypass in humans.

METHODS

Thirty-five patients undergoing cardiac surgery with cardiopulmonary bypass were studied. Bloods were sampled from the pulmonary artery and left atrium at the following times: prior to systemic heparinization, during pulmonary reperfusion and after cardiopulmonary bypass. Plasma concentrations of total and mature adrenomedullin were measured using an immunoradiometric assay kit specific for human adrenomedullin. Intermediate adrenomedullin was calculated as the difference between total adrenomedullin and mature adrenomedullin.

RESULTS

Before cardiopulmonary bypass, mature and intermediate adrenomedullin concentrations were reduced by the pulmonary circulation by approximately 30% and 20%, respectively. However, these effects were not observed during pulmonary reperfusion. Mature, but not intermediate, adrenomedullin was reduced after cardiopulmonary bypass. Furthermore, pulmonary clearance quantity of mature adrenomedullin was significantly enhanced after cardiopulmonary bypass.

CONCLUSION

These results indicate that cardiopulmonary bypass temporally impairs the pulmonary clearance of mature and intermediate adrenomedullin, but clearance of mature, not intermediate adrenomedullin is enhanced after cardiopulmonary bypass.

Structural Analysis of a New Anti-Hypertensive Peptide (β-Lactosin B) Isolated from a Commercial Whey Product

Angiotensin-converting enzyme (ACE) inhibitory activities and anti-hypertensive activities in spontaneously hypertensive rats (SHR) of 12 kinds of commercial peptides of food additive grade were measured. Four peptide products derived from milk proteins showed strong anti-hypertensive activities (>-18.0 mm Hg). A sample of WE80BG derived from whey proteins showed the strongest anti-hypertensive activity (-21.2 +/- 16.9 mm Hg) with a medium level of ACE inhibitory activity (53.6%), and it was subjected to hydrophobic and gel filtration chromatography. From the low molecular weight fraction, an anti-hypertensive peptide was isolated by using reversed-phase HPLC, and it was found to be a tetrapeptide, alanine-leucine-proline-methionine (Ala-Leu-Pro-Met, ALPM), the origin of which was estimated to be beta-lactoglobulin f 142 to 145. At 8 h after oral administration of ALPM in SHR, systolic blood pressure was significantly decreased (-21.4 +/- 7.8 mm Hg), but the IC50 value (concentration of peptide needed to inhibit 50% of the ACE activity) of ALPM was not so high. We named the Ala-Leu-Pro-Met "beta-lactosin B." This peptide is the second anti-hypertensive peptide found from beta-lactoglobulin. Because WE80BG containing ALPM was also found to show the strongest anti-hypertensive activity (-24.5 +/- 10 mm Hg) at 8 h after oral administration in SHR, WE80BG would be suitable for application to the development of a new food expected to have anti-hypertensive effects.

In vivo and in vitro constant expression of GATA-4 in mouse postnatal Sertoli cells

In the mammalian postnatal testis, the biochemical and structural features of Sertoli cells change, depending on developmental stage and spermatogenic cycle, to support efficient spermatogenesis. Consequently, basic transcription factors that determine fundamental properties should be strictly maintained in postnatal Sertoli cells. We have confirmed that GATA-4 expression is kept at a constant level in mouse Sertoli cells during postnatal development, and is also maintained at a constant level in primary cultures, independent of treatment with hormones or the addition of germ cell fractions. In transient transfection assays with the testicular cell line TM3, established from Leydig cells, GATA-4 induced several Sertoli cell-specific genes. In the Sertoli cell line TM4, and in Sertoli cells in primary culture, GATA-4 slightly up-regulated these genes. These results suggest that GATA-4 plays an important role in the regulation of Sertoli cell function, and is exactly regulated in these cells.

Re-evaluation of the reticulo-endothelial system

By injecting lithium carmine (Lit-car) into living animals, Ribbert (1904) and Kiyono (1914) showed that specific staining occurred in some cells in various organs. Kiyono termed those cells "histiocytes" which consisted of free amoeboid cells and cells of reticulo-endothelium. Aschoff (1924) introduced the concept 'reticulo-endothelial system (RES)' for the collection of cells having in common the property of vital staining. Van Furth (1972) proposed the term "mononuclear phagocyte system (MPS)" advocated that RES be replaced by MPS. As a consequence we presently suffer from a "reticulo-endothelial confusion", based on the delusion that cells other than macrophages are not members of the RES. The point that most clearly illustrates this is the fact that the Lit-car-laden cells in the body are named macrophages in modern textbooks of histology. To clarify the confusion, we re-examined the vital staining at light and electron microscopic levels and analyzed the scavenger cells using biochemical methods. Injected Lit-car was actively endocytosed by sinusoidal endothelial cells in the liver and reticular cells in the sinus of lymph nodes. Of note, uptake of the dye was comparatively much lower in macrophages/monocytes. Our findings indicate the existence of scavenger endothelial cells and reticular cells in blood and lymphatic circulations respectively. We name these two systems "the scavenger RES" collectively.

Comparison of sequences of cDNA clones obtained from oligo-capping cDNA libraries with those from unigene

We compared in detail the characteristics of the sequences of the cDNA clones obtained by the oligo-capping method (oligo-capping clones) with that of the sequences in the UniGene database. To compare the completeness of the sequences, three new variables, "fullness-proportion of clones" (the ratio of complete clones to total clones in a library), "fullness-proportion of genes" (the ratio of complete genes to total genes in a library), and "fullness-proportion of database" (the ratio of complete genes to total genes in a database sampled from a library), were defined. The fullness-proportion of clones of oligo-capping clones was 57.3%, 2.2 times larger than that of UniGene (25.9%). The fullness-proportion of genes of oligo-capping clones was 41.8%, 2.4 times larger than that of UniGene (17.8%). When gene length was restricted to > or = 1.5 kb, the fullness-proportion of genes of oligo-capping clones was four times larger than that of UniGene. The fullness-proportion of database of oligo-capping clones was approximately the same as that of UniGene. By simulating the clone redundancy, this coincidence was found to be due to the large redundancy of the UniGene database. Consequently, the cDNA sequence database of oligo-capping clones enabled high throughput selection of full-length cDNA clones.

Significance of reduced uptake of iodinated fatty acid analogue for the evaluation of patients with acute chest pain

OBJECTIVES

To assess whether 15-(p-[iodine-123] iodophenyl)-3-(R,S) methylpentadecanoic acid (BMIPP) imaging can identify previous ischemic areas, BMIPP SPECT was performed in patients with acute chest pain to compare its findings with those of technetium-99m-tetrofosmin (tetrofosmin) SPECT and coronary angiography.

BACKGROUND

Basic studies indicate that BMIPP can identify previous ischemia as reduced tracer uptake.

METHODS

This study prospectively enrolled 111 consecutive patients with acute chest pain without myocardial infarction. Tetrofosmin SPECT was performed at rest within 24 h after the last episode of chest pain. Coronary angiography and BMIPP SPECT were also performed on the following day.

RESULTS

Sixty-four of the 87 patients with coronary stenosis or spasm showed BMIPP abnormalities corresponding to the areas of coronary abnormalities (sensitivity 74%), whereas only 33 of them showed perfusion abnormalities (sensitivity 38%) (p < 0.001). Of 24 patients [corrected] without coronary stenosis or spasm, 22 showed normal BMIPP SPECT (specificity = 92%) [corrected] and 23 showed normal tetrofosmin SPECT (sensitivity = 96%) [corrected]. Coronary stenosis was more often seen in the group with abnormal tetrofosmin/abnormal BMIPP (82%) and with normal tetrofosmin/abnormal BMIPP (69%) than in the group with normal tetrofosmin/normal BMIPP (36%) (p < 0.05). Coronary spasm was observed more often in the group with abnormal tetrofosmin/abnormal BMIPP (83%) and with normal tetrofosmin/abnormal BMIPP (90%) than in the group with normal tetrofosmin/normal BMIPP (27%) (p < 0.05). The extent and severity scores of tetrofosmin and BMIPP in the patients with organic stenosis were significantly higher than those of patients with no organic stenosis or spasm (p < 0.0001).

CONCLUSIONS

These data indicate that BMIPP SPECT may specifically identify previous ischemic lesions due to coronary stenosis or spasm in patients with acute chest pain.

The influence of selection on the evolutionary distance estimated from the base changes observed between homologous nucleotide sequences

In most studies of molecular evolution, the nucleotide base at a site is assumed to change with the apparent rate under functional constraint, and the comparison of base changes between homologous genes is thought to yield the evolutionary distance corresponding to the site-average change rate multiplied by the divergence time. However, this view is not sufficiently successful in estimating the divergence time of species, but mostly results in the construction of tree topology without a time-scale. In the present paper, this problem is investigated theoretically by considering that observed base changes are the results of comparing the survivals through selection of mutated bases. In the case of weak selection, the time course of base changes due to mutation and selection can be obtained analytically, leading to a theoretical equation showing how the selection has influence on the evolutionary distance estimated from the enumeration of base changes. This result provides a new method for estimating the divergence time more accurately from the observed base changes by evaluating both the strength of selection and the mutation rate. The validity of this method is verified by analysing the base changes observed at the third codon positions of amino acid residues with four-fold codon degeneracy in the protein genes of mammalian mitochondria; i.e. the ratios of estimated divergence times are fairly well consistent with a series of fossil records of mammals. Throughout this analysis, it is also suggested that the mutation rates in mitochondrial genomes are almost the same in different lineages of mammals and that the lineage-specific base-change rates indicated previously are due to the selection probably arising from the preference of transfer RNAs to codons.

Ecdysone-inducible foreign gene expression in stably-transformed lepidopteran insect cells

Cultured cell lines that can be stably transformed with inducible gene constructs could prove extremely valuable for the continuous and economical production of recombinant proteins. Toward this goal, we have established 11 clones (designated NISES-BoMo-DK1 to 11) from a previously reported silkworm cell line, NISES-BoMo-DZ. Nine of these clonal lines showed a distinct morphological change. i.e., cell aggregation, in response to treatment with 1 microM 20-hydroxyecdysone (20E). DK10 cells transfected with various reporter assay plasmids under optimal conditions (i.e., 20-30% transfection efficiency) showed inducibility of gene expression by 20E. The 20E treatment of the prototypical DK10 cells resulted in a simultaneous, transient increase of the nuclear ecdysone (E) receptor levels. Further, this inducibility was also observed in a DK10 cell line stably transformed with the reporter plasmid that carries the hygromycin-resistance gene. This offers an opportunity to achieve efficient, continuous production of recombinant proteins. It could also allow high throughput screening for potential E agonists.

Chemistry of zerumbone. 2. Regulation of ring bond cleavage and unique antibacterial activities of zerumbone derivatives

Further investigation of the chemistry of the eleven-membered cyclic sesquiterpene, zerumbone, the major component of the wild ginger, Zingiber zerumbet Smith, has revealed a new selective epoxidation process, a further example of a novel Favorskii-initiated double ring contraction, and a regiospecific fragmentation of zerumbone dibromide derivatives. Several zerumbone derivatives were found to be selective inhibitors of the growth of gram-positive bacteria.

Close correlation of 1-beta-D-arabinofuranosylcytosine 5'-triphosphate, an intracellular active metabolite, to the therapeutic efficacy of N(4)-behenoyl-1-beta-D-arabinofuranosylcytosine therapy for acute myelogenous leukemia

N(4)-Behenoyl-1-beta-D-arabinofuranosylcytosine (BHAC), a prodrug of 1-beta-D-arabinofuranosylcytosine, is used effectively for the treatment of leukemia in Japan. BHAC therapy may be more effective if it is delivered in conjunction with monitoring of 1-beta-D-arabinofuranosylcytosine 5'-triphosphate (ara-CTP), the intracellular active metabolite of ara-C derived from BHAC. However, previous monitoring methods for ara-CTP were insufficiently sensitive. Here, using our new sensitive method, we evaluated the ara-CTP pharmacokinetics in relation to the therapeutic response in 11 acute myelogenous leukemia patients who received a 2-h infusion of BHAC (70 mg / m(2)) in combination remission induction therapy. ara-CTP could be monitored at levels under 1 mM. BHAC maintained effective levels of plasma ara-C and intracellular ara-CTP for a longer time, even compared with historical values of high-dose ara-C. The area under the concentration-time curve of ara-CTP was significantly greater in the patients with complete remission than in the patients without response. This greater amount of ara-CTP was attributed to the higher ara-CTP concentrations achieved in the responding patients. There was no apparent difference of plasma ara-C pharmacokinetics between the two groups. Thus, for the first time, the ara-CTP pharmacokinetics was evaluated in relation to the therapeutic effect of BHAC, and the importance of ara-CTP was proven. Administration of optimal BHAC therapy may require monitoring of the ara-CTP pharmacokinetics in each individual patient.

The hydrogen peroxide/copper ion system, but not other metal-catalyzed oxidation systems, produces protein-bound dityrosine

Dityrosine formation leads to the cross-linking of proteins intra- or intermolecularly. The formation of dityrosine in lens proteins oxidized by metal-catalyzed oxidation (MCO) systems was estimated by chemical and immunochemical methods. Among the four MCO systems examined (H(2)O(2)/Cu, H(2)O(2)/Fe-ethylenediaminetetraacetic acid (Fe-EDTA), ascorbate/Cu, ascorbate/Fe-EDTA), the treatment with H(2)O(2)/Cu preferentially caused dityrosine formation in the lens proteins. The success of oxidative protein modification with all the MCO systems was confirmed by carbonyl formation estimated using 2,4-dinitrophenylhydrazine. The loss of tyrosine by the MCO systems was partly due to the formation of protein-bound 3,4-dihydroxyphenylalanine. The formation of dityrosine specific to H(2)O(2)/Cu was confirmed by using poly-(Glu, Ala, Tyr) and N-acetyl-tyrosine as a substrate. The dissolved oxygen concentration in the H(2)O(2)/Cu system hardly affected the amount of dityrosine formation, suggesting that dityrosine generation by the H(2)O(2)/Cu system is independent of oxygen concentration. Moreover, the combination of copper ion with H(2)O(2) is the most effective system for dityrosine formation among various metal ions examined. The addition of reducing agents, glutathione or ascorbic acid, into the H(2)O(2)/Cu system suppressed the generation of the dityrosine moiety, suggesting effective quench of tyrosyl radicals by the reducing agents.

Long-term follow-up of the clinical efficacy of chemotherapy for acute myeloid leukemia at a single institute

A retrospective study was performed on 125 patients with de-novo acute myeloid leukemia (AML) who had received first remission induction therapy at Fukui Medical University Hospital in the 16 years between 1983 and 1998. For remission induction therapies, patients in the 1980s received mainly behenoylcytarabine (BHAC), 6-mercaptopurine (6-MP), and prednisolone (PSL), plus aclarubicin (ACR) or daunorubicin (DNR). Patients in the 1990s received mainly BHAC, 6-MP, and etoposide (VP-16) plus DNR or mitoxantrone (MIT) or idarubicin (IDA). Patients with hypoplastic bone marrow received low-dose cytarabine (Ara-C) therapy or cytarabine ocfosfate (SPAC). Since 1992, patients with French-American-British disease classification of M3 have received all-trans retinoic acid (ATRA) (+/-chemotherapy). In the 1990s, more intensified postremission therapy was performed compared with that done in the 1980s. The complete remission (CR) rate of all patients was 58%. Predicted 6-year overall survival (OS) and disease-free survival (DFS) rates in the CR patients were 22% and 28%, respectively. Multivariate analysis showed age and leukocyte counts as significant prognostic factors regarding CR, OS, and DFS rates. The CR and OS rates in the 1990s were improved significantly from those in the 1980s, at 69% versus 48% (P = 0.016), and 32% versus 15% (P = 0.0014), respectively. The early death rate, within 30 days, was decreased from 26% in the 1980s to 9% in the 1990s (P = 0.013). This decrease was thought to be the main cause of the high CR rate in the 1990s. However, DFS was not significantly improved. It is necessary to establish more effective postremission therapies in order to reduce the relapse rate and improve the prognosis.

Monitoring of intracellular 1-beta-D-arabinofuranosylcytosine 5'-triphosphate in 1-beta-D-arabinofuranosylcytosine therapy at low and conventional doses

1-beta-D-Arabinofuranosylcytosine (ara-C) is used empirically at a low, conventional, or high dose. Ara-C therapy may be optimal if it is directed by the clinical pharmacokinetics of the intracellular active metabolite of ara-C, 1-beta-D-arabinofuranosylcytosine 5'-triphosphate (ara-CTP). However, ara-CTP has seldom been monitored during low- and conventional-dose ara-C therapies because detection methods were insufficiently sensitive. Here, with the use of our newly established method (Cancer Res., 56, 1800 -- 1804 (1996)), ara-CTP was monitored in leukemic cells from acute myelogenous leukemia patients receiving low- or conventional-dose ara-C [subcutaneous ara-C administration (10 mg / m(2) ) (3 patients), continuous ara-C infusion (20 or 70 mg / m(2) / 24 h) (7 patients), 2-h ara-C infusion (70 mg / m(2) ) (4 patients), and 2-h infusion of N(4)-behenoyl-1-beta-D-arabinofuranosylcytosine, a deaminase-resistant ara-C derivative (70 mg / m(2) ) (6 patients)]. Ara-CTP could be determined at levels under 1 microM. There was a close correlation between the elimination half-life values of the plasma ara-C and the intracellular ara-CTP. The presence of ara-C in the plasma was important to maintain ara-CTP. The continuous ara-C and the 2-h N(4)-behenoyl-1-beta-D-arabinofuranosylcytosine infusions maintained ara-CTP and the plasma ara-C longer than the subcutaneous ara-C or the 2-h ara-C infusion. They also afforded relatively higher ara-CTP concentrations, and consequently produced ara-CTP more efficiently than the 2-h ara-C infusion. Different administration methods produced different quantities of ara-CTP even at the same dose.

Bile acid reflux and possible inhibition of Helicobacter pylori infection in subjects without gastric surgery

Bile acids are generally known to inhibit growth of Helicobacter pylori in vitro, but whether they do so in humans with no gastric surgery has been uncertain. The present study addresses this issue. Among healthy control subjects with preserved acid secretion, H. pylori-positive subjects were older and had lower gastric bile acid concentrations than H. pylori-negative subjects (P < 0.05). Among gastric ulcer patients with preserved acid secretion, H. pylori-positive patients had a higher basal acid output than H. pylori-negative patients (P < 0.05). Among H. pylori-positive subjects with preserved acid secretion, duodenal ulcer patients had a higher basal and maximum acid output than healthy control subjects (P < 0.01). In conclusion, gastric bile acids may suppress initial stages of H. pylori infection in subjects without gastric surgery. However gastric bile acids may have little effect on peptic ulcer disease, once H. pylori infection is established.

Inhibitory effect of quinolone antimicrobial and nonsteroidal anti-inflammatory drugs on a medium chain acyl-CoA synthetase

The inhibitory effects of quinolone antimicrobial agents and nonsteroidal anti-inflammatory drugs on purified mouse liver mitochondrial medium chain acyl-CoA synthetase catalyzing the first reaction of glycine conjugation were examined, using hexanoic acid as a substrate. Enoxacin, ofloxacin, nalidixic acid, diflunisal, salicylic acid, 2-hydroxynaphthoic acid, and 2-hydroxydodecanoic acid, which do not act as substrates, were potent inhibitors. Diflunisal, nalidixic acid, salicylic acid, 2-hydroxynaphthoic acid, and 2-hydroxydodecanoic acid inhibited competitively this medium chain acyl-CoA synthetase with K(i) values of 0.6, 12.4, 19.6, 13.4, and 15.0 microM, respectively. Enoxacin and ofloxacin inhibited this medium chain acyl-CoA synthetase in a mixed-type manner with K(i) values of 23.7 and 38.2 microM, respectively. Felbinac, which is a substrate, inhibited the activity of this medium chain acyl-CoA synthetase for hexanoic acid (IC50 = 25 microM). The concomitant presence of enoxacin and felbinac strongly inhibited this medium chain acyl-CoA synthetase. These findings indicate that medium chain acyl-CoA synthetases may be influenced by quinolone antimicrobial and nonsteroidal anti-inflammatory drugs.

Successful lamivudine therapy for post-chemotherapeutic fulminant hepatitis B in a hepatitis B virus carrier with non-Hodgkin's lymphoma: case report and review of the literature

Reactivation of hepatitis B virus (HBV), especially after withdrawal of corticosteroids is a well-known complication during chemotherapy for lymphoma. The high mortality makes this complication one of the major obstacles to completing the standard treatment for lymphoma in HBV carriers. We report a 58-year-old Japanese male HBV carrier who developed fulminant hepatitis after chemotherapy with cyclophosphamide and doxorubicin. Lamivudine was introduced since his hepatitis was progressive under supportive treatment and showed an elevated level of HBV DNA. After initiation of lamivudine, HBV DNA decreased to be below the limit of detection within 3 weeks, and all chemical tests for liver function recovered to the normal level within 4 weeks, except for a slight elevation of total-bilirubin. There were no remarkable adverse effects observed. To the best of our knowledge, six cases of post-chemotherapeutic fulminant hepatitis including ours have been treated with lamivudine. A review of these cases indicated that lamivudine induced a prompt antiviral, biochemical, and clinical response. Lamivudine is highly recommended for post-chemotherapeutic fulminant hepatitis caused by reactivation of HBV.

Sodium butyrate induces transcription from the G alpha(i2) gene promoter through multiple Sp1 sites in the promoter and by activating the MEK-ERK signal transduction pathway

Sodium butyrate, an erythroid differentiation inducer and a histone deacetylase inhibitor, increases G alpha(i2) levels in differentiating K562 cells. Here we show that sodium butyrate induces G alpha(i2) gene transcription via sequences at -50/-36 and -92/-85 in the G alpha(i2) gene promoter. Both sequences contain core sequence motif for Sp1 binding; electrophoretic mobility shift as well as supershift assays confirmed binding to Sp1. Transcription from the G alpha(i2) gene promoter was also activated by two other histone deacetylase inhibitors, trichostatin A and Helminthsporium carbonium toxin (HC toxin), which also induce erythroblastic differentiation in K562 cells. However, hydroxyurea, a potent erythroid differentiation inducer in these cells, did not activate transcription from this gene promoter, indicating that promoter activation is inducer-specific. Mutations within the Sp1 sites at -50/-36 and -92/-85 in the G alpha(i2) gene promoter substantially decreased transcriptional activation by sodium butyrate, trichostatin A, or HC toxin. Transfection with constitutively activated ERKs indicated that this promoter can be activated through the MEK-ERK signal transduction pathway. Inhibition of the MEK-ERK pathway with U0126 or reduction in the expression of endogenous ERK with an antisense oligonucleotide to ERK significantly inhibited sodium butyrate- and HC toxin-induced transcription but had no effect on trichostatin A-induced transcription. Inhibition of the JNK and p38 MAPKs, using selective inhibitors, had no effect on sodium butyrate-induced transcription. In cells in which sodium butyrate induction of promoter activation had been inhibited by various concentrations of U0126, constitutively activated ERK2 reversed this inhibition. These results show that the MEK-ERK signal transduction pathway is important in butyrate signaling, which eventually converges in the cell nucleus.

AT oligonucleotides inducing B lymphocyte activation exist in probiotic Lactobacillus gasseri

This study determined oligonucleotide sequences of mitogenic DNA derived from lactic acid bacteria (LAB). The chromosomal DNA, which was purified from 12 out of 16 strains of Lactobacillus acidophilus group LAB, induced proliferation of splenic lymphocytes. When DNA from L. gasseri JCM1131T was cloned and amplified using PCR, the mitogenic activities of B lymphocytes were significantly increased by 108 of 321 DNA clones. Ten high homologous nucleotide sequences were found as possible DNA sequences of mitogens, and were then chemically synthesized (sOL-LG1 to sOL-LG10). Two nucleotide sequences (sOL-LG7 and sOL-LG10) that consist of only A and T nucleotides (AT oligonucleotides) were characterized as B lymphocyte specific mitogens because they resulted in proliferation of B lymphocytes but not of T lymphocytes. sOL-LG7 preferentially bound to large B lymphocytes and enhanced the expression of the CD86 antigen more than the CD69 antigen on B lymphocytes. The findings show that mitogenic AT oligonucleotides are likely to restrict pre-activated subsets of B lymphocytes. This study demonstrated that novel AT oligonucleotides triggering B lymphocyte mitogenic responses exist in the nucleoids of L. gasseri and proposed that they have potential as applicants for the production of new functional foods, "Bio-Defense Foods".

[The measurement of immature reticulocyte fractions and clinical significance]

We evaluated automated analysis for the measurement of immature reticulocyte fraction(IRF) in 222 blood samples. IRF was performed by R-3000 & XE-2100(Sysmex), VEGA RETIC LC141(Horiba), ADVIA 120(Bayer medical), CELL DYN4000(Abbott) or GEN'S(Coulter), and compared with measurements obtained by visual counting. A subfraction of IRF was also determined using different modalities on all analyzers. The values of IRF were stable after blood storage for 48 hours at 4 degrees C and 8 hours at room temperature. A good correlation of IRF among these analyzers was obtained(r = 0.629-0.869), but the normal ranges in the percentage of IRF varied according to analyzers. However, an elevation in the percentage of IRF is the first sign of bone marrow recovery after chemotherapy and the bone marrow transplantation in the majority of leukemic patients. We suggest that IRF counting is useful for the estimation of early phase erythropoiesis in patients who have successful bone marrow engraftment following bone marrow transplantation.

Features of distamycin preferential binding sites on natural DNA predicted using differential scanning calorimetry

The interaction of distamycin with ColE1 DNA was examined by using differential scanning calorimetry (DSC) taking the helix-coil transition theory of DNA into consideration. Our results here strongly indicate that the affinity of distamycin to DNA, at a low distamycin concentration, depends highly on the DNA sequence, and preferential binding occurs to the sites of four to six successive A-T pairs having two or more successive G-C pairs on both their ends.

Differential effect of PKC isoform on insulin- and phorbol ester-stimulated glucose uptake mechanism in rat adipocytes

Insulin stimulates glucose uptake in association with phosphatidylinositol (PI) 3-kinase activation mechanisms in rat adipocytes. Insulin stimulated glucose uptake to 6.5-fold, and 12-o-tetradecanoyl phorbol 13-acetate (TPA) also stimulated glucose uptake to 4.5-fold in rat adipocytes. We examined these differences in glucose uptake, PKCzeta activation, and PI 3-kinase activation after stimulation with insulin and TPA. TPA stimulated PI 3-kinase activity and increased the p85 subunit of PI 3-kinase immunoreactivity in anti-phosphotyrosine antibody-immunoprecipitated protein. Insulin and TPA provoked increases in membrane PKCzeta immunoreactivity. The PI 3-kinase inhibitor, wortmannin, suppressed insulin-induced increases in glucose uptake, PI 3-kinase activity, and PKCzeta activation. Wortmannin also suppressed TPA-induced PI 3-kinase activity and PKCzeta activation but suppressed TPA-induced glucose uptake to only a small extent. The PKC inhibitor, Go6976, which only inhibits conventional PKCalpha and _, suppressed TPA-induced glucose uptake, but suppressed insulin-induced glucose uptake to only a small extent. On the other hand, the PKC inhibitor, RO32-0432, which inhibits conventional, novel, and atypical PKCs, markedly suppressed both insulin- and TPA-induced glucose uptake. These results suggest that insulin-induced glucose uptake is mainly mediated by PI 3-kinase-PKCzeta signaling, whereas phorbol ester-induced glucose uptake is mainly mediated by conventional PKC despite PI 3-kinase and PKCzeta activations.

Contractile responses of the basilar artery isolated from rabbits exposed to 8-day head-down tilt

In the present study, the effects of head-down tilt (HDT) on contractile responses of basilar and popliteal arteries were investigated in vitro. The arteries were isolated from rabbits exposed to 8 d of 45 degrees HDT. Isometric tension and intracellular calcium were measured in an organ bath perfused with physiological salt solution. In the HDT rabbits, contractile response to norepinephrine (NE) was attenuated in the basilar artery, but not in the popliteal artery compared with control rabbits. HDT did not change the responses to either KCl or 5-hydroxytryptamine in both arteries. In the response of basilar artery to NE, the difference in both [Ca(2+)](i) transient and Ca sensitivity between control and HDT rabbits were statistically not significant. The response of the basilar artery to phenylephrine, a selective alpha(1)-adrenergic agonist, was also attenuated by HDT. Treatment with propranolol, a beta-adrenergic blockade, did not affect the response to NE in the basilar arteries isolated from control rabbits, but it significantly enhanced the response in the basilar arteries from HDT rabbits. These results suggest that exposure to 8-d HDT decreases a contractile response of the basilar artery to NE in rabbits. The reduction of NE-induced contraction is probably attributable to both decreased Ca transient and decreased Ca sensitivity, and decreased alpha(1)-adrenoceptor activity and increased beta-adrenoceptor activity seem to be involved in the mechanism.

1,1-Diphenyl-2-picrylhydrazyl radical-scavenging active compounds from greater cardamom (Amomum subulatum Roxb.)

Constituents of the fruits of greater cardamom (Amomum subulatum) were fractionated into three fractions, the dichloromethane extract, and the ethyl acetate-soluble and water-soluble fractions of the 70% aqueous acetone extract. The ethyl acetate-soluble fraction showed a high radical-scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH). Four compounds were isolated from the ethyl acetate-soluble fraction, and their structures were ascribed to protocatechualdehyde (1), protocatechuic acid (2), 1,7-bis(3,4-dihydroxyphenyl)hepta-4E,6E-dien-3-one (3) and 2,3,7-trihydroxy-5-(3,4-dihydroxy-E-styryl)-6,7,8,9-tetrahydro-5H-benzocycloheptene (4) on the basis of spectroscopic evidence. This is the first isolation of these compounds from greater cardamom. In particular, 4 was a new type of cyclic diarylheptanoid. DPPH radical-scavenging activity of these compounds was measured by colorimetric analysis. Compounds 1 and 3 showed stronger activity than such natural antioxidants as alpha-tocopherol and L-ascorbic acid. Compounds 2 and 4 were comparable to alpha-tocopherol and L-ascorbic acid.

[Reversed C.P.C. :Case of 14-year old girl with large abnormal cells in her bone marrow]

A 14-year-old female was admitted to our institute with arthralgia of the left pelvis. Magnetic resonance image analysis revealed the presence of a low-density area in her left pelvis. Although the complete blood count was almost within normal ranges, large abnormal cells with a round-shaped multi-nucleus and abundant cytoplasm containing coarse basophilic granules were noted in her bone marrow smear. She was diagnosed with mastocytosis after laboratory examinations. Nine months later, after intensive chemotherapy, the patient died.

Postnatal differentiation of local networks in the nucleus of the tractus solitarius

Whole-cell voltage-clamp recordings from rat brain slice preparation were used to investigate a possible developmental change in the patterns of synaptic interactions among the nucleus tractus solitarii neurons by analysing spontaneous postsynaptic current activity. Three types of patterns of spontaneous postsynaptic current activity were distinguished in the nucleus tractus solitarii neurons which showed high activities in terms of current frequency and amplitude. The first type was characterized by the presence in an individual cell of high frequencies and large amplitudes of both spontaneous glutamatergic and GABAergic postsynaptic currents, and observed exclusively in postnatal day 0-7 rats. The second and third types of cells showed predominant either inhibitory or excitatory postsynaptic currents, respectively. After postnatal day 5, nucleus tractus solitarii neurons with high background activity were shown to differentiate into either the second or the third type, with the latter of about 70% in the adult caudal/intermediate nucleus tractus solitarii. Axon collaterals of some medium to large neurons seemed to be decreased by pruning during postnatal development. The early postnatal differentiation of background synaptic activity observed in the nucleus tractus solitarii presumably reflects the local network reorganization and may be related to maturational changes in cardiovascular and respiratory functions.