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Lactococcus lactis has been reported unable to directly incorporate mononucleotides but instead requires their external dephosphorylation by nucleotidases to the corresponding nucleosides prior to ...

Although most lactic acid bacteria do not directly incorporate purine nucleotides, the strain Lactobacillus gasseri PA-3 was found to incorporate purine mononucleotides. To determine whether the direct uptake of purine mononucleotides is dependent on the species or strain of lactic acid bacteria, incorporation of purine mononucleotides was assessed in L. gasseri, Lactcoccus lactis sbsp. lactis, Streptococcus thermophilus and other species of lactic acid bacteria. Each bacterial strain was incubated with 32P-AMP or 14C-adenosine and the incorporation of each purine was evaluated by measuring their radioactivity. All investigated strains of L. gasseri incorporated 32P-AMP, whereas strains of S. thermophilus and most strains of L. lactis did not. Incorporation of 32P-AMP into strains of Pediococcus was dependent on the strain or species of that genus of bacteria. All investigated strains, except for one strain of L. gasseri, incorporated 14C-adenosine, with S. thermophilus, L. lactis and Pediococcus generally displaying greater incorporation of 14C-adenosine than L. gasseri. Although most lactic acid bacteria such as S. thermophiles and L. lactis do not incorporate purine mononucleotides, some species such as L. gasseri directly incorporate purine mononucleotides. These findings indicate that the preferential incorporation of purine mononucleotides or nucleosides by lactic acid bacteria is dependent on the species or strain.

Excessive intake of purine-rich foods elevates serum uric acid levels, making it a risk factor for hyperuricemia. We hypothesized that lactic acid bacteria ingested with food might utilize purines and contribute to their decreased absorption in the intestines, thereby preventing hyperuricemia. We previously reported that Lactobacillus gasseri PA-3 (PA-3) incorporates adenosine/inosine and related purines and that oral ingestion of PA-3 reduced the absorption of these purines in rats. However, it is unclear whether PA-3 also decreases the absorption of other purines, such as guanosine 5'-monophosphate (GMP) and guanosine. This study investigated whether PA-3 incorporates GMP and guanosine and reduces their absorption in rats. PA-3 incorporated both purines, with

Lactobacillus gasseri PA-3 (PA-3) is a bacterial strain with a strong ability to degrade purine nucleosides. We previously showed that PA-3 incorporates purines in vitro and that oral administration of PA-3 and purines to rats attenuated their absorption of purines. It remains unclear whether these effects of PA-3 depend on bacterial strains. This study therefore compared the abilities of PA-3 and another bacterial strain of L. gasseri, OLL2996, which has shown decreased ability to degrade purine nucleosides in vitro, to incorporate purine nucleosides and to inhibit the absorption of purines fed to rats. Each bacterial strain was incubated in the presence of 14C-adenosine or 14C-inosine and the incorporation of each purine was evaluated by measuring their radioactivity. In vivo, rats were fed 14C-labeled purines along with PA-3 or OLL2996 and the absorption of these 14C-labeled purines was evaluated by analyzing radioactivity of blood samples. PA-3 incorporated about twice as much 14C-adenosine and 14C-inosine as OLL2996. The elevation of radioactivity levels in blood was 10-20% lower in rats treated with PA-3 than in control rats, after feeding with both 14C-adenosine and 14C-inosine as purines. In contrast, treatment with OLL2996 did not have statistically significant effects on radioactivity compared with the control group. These results indicate that the magnitude of bacterial inhibition of purine absorption is dependent on bacterial strain, correlating at least partly with the ability to incorporate and degrade purines.

It is well accepted that frequent and heavy intake of purine-rich foods causes elevation of serum uric acid levels, which is a risk factor of hyperuricemia. Reducing intestinal absorption of dietary purines may attenuate the elevation of serum uric acid levels and exacerbation of hyperuricemia. This reduction may be achieved by the ingestion of lactic acid bacteria that take up purines in the intestine. In this study, we investigated the degree of uptake and utilization of purines of three lactobacilli strains. Among them, Lactobacillus gasseri PA-3 (PA-3) showed the greatest incorporation of 14C-adenine. PA-3 also incorporated 14C-adenosine and 14C-AMP. Additionally, using defined growth medium, PA-3 demonstrated greater proliferation in the presence of these purines than in their absence. Although further investigation is required, ingestion of PA-3 may lower serum uric acid levels by reducing intestinal absorption of purines in humans.

The effects of freeze damage on the crumb grain and on the underlying gluten fibrils of baked breads were studied using scanning electron microscopy (SEM) and magnetic resonance imaging (MRI). Sweet and white bread doughs were stored at -20°C and subjected to freeze-thaw cycles. SEM images of grain pore walls that were washed with distilled water (20°C) clearly showed that gluten fibrils forming the skeletal framework of pore walls were cut and became coarse and nonuniform strings and that many knots were generated on gluten fibrils from freeze damage. An increase in the number of freeze-thaw cycles increased both the coarseness of the gluten fibrils and the size of the knots, although the apparent damage was not clearly detected on the crumb grain with MRI.

The fermentation process for frozen doughs using freeze-sensitive (Saccharomyces cerevisiae, Kyowa for sweet bread; S. cerevisiae, FC for white bread) and freeze-tolerant (S. cerevisiae, YF for sweet bread) yeasts was traced by magnetic resonance imaging (MRI). Grain network structures of baked breads were also visualized by MRI. Prefermentation before freezing, punching and remolding, or resheeting and molding treatments increased loaf volume by 10 to 110% for the baked breads using freeze-tolerant yeast, while these treatments decreased loaf volume by 70% using freeze-sensitive yeast. The first fermentation before freezing and the second fermentation with punching or resheeting after thawing are useful for obtaining good quality breads from frozen dough using freeze-tolerant yeast.

Fermentation processes of bread doughs were traced by MRI (magnetic resonance Imaging), which suggests that punching and rounding treatment after the first fermentation promotes the development of elasticity and extensibility of gluten fibrils that makes thin grain walls of the pores connecting between adjacent pores with small holes, and a thin smooth crust after baking. While pore generation was small, expansion of the dough was low gluten networks formed were large and coarse, and gluten fibrils were undeveloped in the frozen dough, Prefermentation could not essentially alleviate the inferior properties of the frozen dough. The grain structures of the bread using frozen dough were characterized by thick network walls without the connection between pores and a thick crust with rough surface. La fermentation de la pâte a pain est suivie par imagerie RMN. Le petrissage et le faconnage apres la premiere fermentation influence le developpement de l'elasticite et de l'extensibilite des fibrilles de gluten, permettant de faire communiquer les pores et d'obtenir une croute fine et moelleuse apres cuisson. Le phenomene est moins marque dans la pâte congelee pour une qualite de pain inferieure.

In this paper we describe polarization spectroscopy measurements of O5+(1s23p 2P3/2), following single-electron capture from He and H2. A novel arrangement for measurements of the polarization degree has been developed to reduce the systematic error. These measurements are shown as a function of projectile velocity, which was varied from 0.34 to 0.55 au. A simple model for the results with H2 is presented by considering the velocity dependence of capture cross sections for each 4l state and the cascade from 4l to 3p. However, for the case of the He target, no such simple model is found to be consistent with the experimental results.

Ontogenetic changes of water status and accumulated soluble compounds in growing cherry fruits were examined by 1H NMR imaging, 1H NMR localized spectral imaging and 13C NMR spectroscopy. Water status was contradictory between the seed and pericarp of the fruit in relation to growth stages. There was a large amount of high-mobility water present in the seed, whereas only a small amount was present in the pericarp during the early growth stages. The diffusion coefficient of seed water was determined as 2.1×10-5 cm2 s-1 at the maximum, which corresponded to that of pure water (2.14×10-5 cm2 s-1 at 25±1°C). Water in the seed decreased in amount and mobility whereas that in the pericarp increased with maturation. The diffusion coefficient of pericarp water increased from 1.0×10-5 to 1.6×10-5 cm2 s-1 as the fruit ripened. Sugars accumulated in the pericarp with increasing water content, but disappeared with further ripening of the fruit. This suggests that over-maturation results in loss of sweetness and firmness. NMR imaging could probe changes in the physiological condition of the fruit with growth stages. © 1997 John Wiley & Sons, Ltd.

The distribution and fluctuation of sugars in germinating barley seeds were examined by 13 C nuclear magnetic resonance (NMR) spectroscopy, 1 H-NMR imaging and 1 H-NMR localized spectroscopy in relation to morphology. Maltose, sucrose, fructose and oils were detected in intact imbibed seeds by 13 C-NMR spectra. During the first 6d of germination, the maltose content increased and the oil content gradually decreased, whilst the levels of sucrose and fructose remained constant. Sugars were located by 1 H-NMR images and 1 H-NMR localized spectra in the vascular bundle of the seeds as well as in the solubilized endosperm. They were also detected in the shoots. The sugars detected in an 80% ethanol shoot extract were sucrose and glucose, which were located in the vascular bundles but not in the mesophyll cells of the coleoptile. They were also located in the basal part of the shoot, but not above 7 mm from the scutellum. The data suggest that the sugars are primarily transported through the vascular bundles and, at the same time, rapidly incorporated into mesophyll cells in the leaves.

Changes in water status of intact developing cherry tomato fruits were followed by 1 H NMR imaging and 1 H NMR spectroscopy. In small green fruits, large amounts of water were located in the epidermis and neighbouring cells, and in seed envelopes and seeds. High mobility water with long spin-lattice relaxation times ( T 1 ) in the seeds of small green fruits disappeared as the fruit grew. The content of high mobility water in locular cavities, including seed envelopes, increased as ontogeny advanced. Low mobility water (short T 1 ) in the pericarp and dissepiments of the small and large green fruits increased in quantity and mobility during maturation. In some of the several water compartments in large green fruits water content declined during maturation. Changes in the physical state of water appeared to reflect changes in the physiology of the fruits. The mobility of sugars increased during fruit ripening.

Raman spectra of n‐type gallium nitride with different carrier concentrations have been measured. The LO phonon band shifted towards the high‐frequency side and broadened with an increase in carrier concentration. Results showed that the LO phonon was coupled to the overdamped plasmon in gallium nitride. The carrier concentrations and damping constants were determined by line‐shape fitting of the coupled modes and compared to values obtained from Hall measurements. The carrier concentrations obtained from the two methods agree well. As a result, the dominant scattering mechanisms in gallium nitride are deformation‐potential and electro‐optic mechanisms.

In order to examine the transverse distribution of scattered light and chlorophyll fluorescence in intact rice leaves, a micro-fluorescence imaging system was devised using a microscope, a CCD camera with an image intensifier, an Ar and a He-Ne laser light source, an image processor, and a microcomputer. A laser light was projected vertically on to the surface of a rice leaf segment at a cut-edge, and scattered light and induced fluorescence were observed at the cut-section from a 90° angle to the axis of the laser beam. The intensity of scattered light showed a maximum at several micrometres depth from the leaf surface and a steep gradient afterwards. Fluorescence reached a maximum crossing with the decline curve of the scattered light. The maximum of fluorescence measured at 741 nm was observed at a greater depth from the leaf surface than that at 687 nm, suggesting that part of the fluorescence of the longer wavelength was emitted due to absorption of fluorescence of the shorter wavelength. Profiles of the scattered light and the chlorophyll fluorescence depended on leaf anatomy.

We demonstrate here that two-dimensional electron gas is successfully formed at the interface which is prepared by the Cl 2 gas etching of MBE grown GaAs followed by the overgrowth of n-AlGaAs in an ultra-high vacuum multichamber MBE system. Electron mobility as high as 114.1700 cm 2 /V s at 9.8 K is achieved for the carrier concentrntion N s =4.5×10 11 cm -2 . The carbon incorporated at the interface is found to he n dominant additional scatterer for the electrons. It is shown that the carbon is incorporated mainly in the MBE chamber during the period of the sample transfer, and that the degradation caused by Cl 2 etching itself is sufficiently small

We found a new spin-valve structure in which low coercivity coexists with high GMR ratio is substrate/Ta/NiFe/PtMn/CoFe/Ru/Ox/CoFe/Cu/CoFe/Cu/Ta-O. "Ox" means that Ru layer surface was exposed to oxygen gas. In this structure, the free layer is separated from the top specular layer by a copper layer and shows no increase in coercivity. Furthermore, the free layer was well oriented due to the thin oxide layer in the bottom pinned layer and the coercivity did not increase. After annealing at 295/spl deg/C, GMR and the exchange-bias field showed little change, which meant the oxide layers were stable. For the structure glass/Ta [3 nm]/NiFe [2 nm]/PtMn [10 nm]/CoFe [1.5 nm]/Ru [0.8 nm]/Ox/CoFe [2 nm]/Cu [2 nm]/CoFe [2 nm]/Cu [1 nm]Ta-O [1 nm], GMR ratio of 14.9% and change in sheet resistance of 3.3 ohms were obtained. The coercivity of the free layer exhibited 0.4 Oe.

The sequence of 5,028 nucleotides, including one open reading frame (ORF), of rice tungro bacilliform virus (RTBV) dsDNA was determined. The predicted translational product comprises 1,675 amino acids and has Mr of 194,134 (p194). The amino acid sequences of three tryptic fragments from the 32 k capsid protein of RTBV (p32) were found in the predicted translational product indicating that the ORF codes for the RTBV capsid protein.

Activation spectra of photochemical reactions were measured by a flash spectrophotometer in leaves having varying chlorophyll contents at different stages of greening. The increase of chlorophyll concentration up to 30 nmol cm-2 elevated the rates of photochemical reactions at all wavelengths of light used, and was found to be produced by an increase in the amounts of reaction centres. Further accumulation of chlorophyll up to 40 nmol cm-2 was associated with an increase in light-harvesting chlorophyll, an improved rate of photochemical reactions around 600 nm and at 700 nm, and self-absorption and screening effects where chlorophyll absorbed maximally (400–450 nm and around 680 nm).

Fluorescence induced in tree leaves (12 deciduous and 16 evergreen trees) by an Ar laser was measured by a multi-channel spectrometer. The spectra had peaks at around 430 nm, 530 nm and 600 nm as well as those of chlorophyll fluorescence (685 nm and 740 nm). The ratio between the two peaks of chlorophyll fluorescence changed with chlorophyll content in the leaves. Seasonal changes of the fluorescence spectra showed characteristic properties for individual plant species, therefore, knowing terrestrial vegetation, measurement of the laser induced fluorescence (LIF) is a useful means for remote-sensing of the ecological and physiological status of plants. >

We have investigated the afterglow decay rates of sixteen iodine ion, I(II), laser lines in spontaneous emissions. All lines originate from the four triplet terms of the 5s25p3(2D0)6p electronic configuration. The variation of the I(II) spontaneous emission decay rates with increasing iodine pressure provides direct evidence that a charge‐transfer reaction involving the ground‐state atomic helium ion and a ground‐state iodine atom is a primary source of excitation for the upper levels of the helium‐iodine ion laser. A total velocity‐averaged cross section, σ (He+‐I), of 3×10−16 cm2 has been measured.

An experimental double-probe technique is described which allows the He(+) ion density to be measured directly as a function of time in the afterglow of a helium-metal-vapor discharge. As an application example, two CW laser transitions of the He-Hg(+) laser at 6150 and 7944 A are considered which both arise from excited 7p (2) P terms of Hg II. The time-resolved double-probe technique is used to measure the destruction rate of the He(+) ion density, which is then compared with the spontaneous-emission decay rate for 7p (2) P terms of Hg II. The results obtained show unambiguously and directly that the dominant excitation process for the two transitions considered is a charge-transfer collisional reaction of the form He(+) plus Hg yields He plus metastable Hg(+) plus the energy defect for this reaction. It is noted that the time-resolved double-probe technique may provide a simple method for measuring ion mobilities in a multi-ion plasma.

The Rutherford back-scattering method was applied to observe the Xe flash lamp annealing process of 31P+ ion implanted (100) Si wafers, the lamp energy being 15-28 J cm-2. The n-type Si wafers with resistivity 20 Omega cm were implanted with 1*1014-3*1015 31P+ ions cm-2 at 50 keV. For the Si wafers implanted with 1*1014 31P+ ions cm-2, the disordered region produced by implantation can be completely annealed at some lamp energies. With higher doses than 1015 31P+ ions cm-2, residual disorders can be observed and there exists on optimum lamp energy which depends on the ion dose, for example 25 J cm-2 for 1*1015 31P+ ions cm-2 20 J cm-2 for 3*1015 31P+ ions cm-2.

A new monitoring system has been developed for continuously measuring the concentration of total nonvolatile impurities in ultrapure water. The measuring method is based on the principle of determining the Residue After Evaporation (RAE) of atomized droplets, taking account of the particle deposition loss. The system consists of a water atomizing unit, a droplet evaporating and drying unit, an air diluter, a fine particle counter, etc. For the particle counter, a Condensation Nucleus Counter (CMC) is used; this counter is a mixing type, able to detect particles larger than 0.01 μm. It is verified from both the theoretical analysis and the experimental results that this monitor can rapidly detect very low impurity concentrations by counting the number concentration of aerosol particles.

A comparative study of the rapidly thermal-processed molecular beam epitaxial GaAs grown on Si and GaAs substrates is made by deep-level transient spectroscopy (DLTS). Rapid thermal processing (RTP) was performed at 910 degrees C for 9 s with SiO2 encapsulation. In the MBE layer on Si, the traps A1 (Ec-0.65 eV) and A2 (Ec-0.81 eV) are observed in addition to the trap M1 (Ec-0.18 eV) and M4 (Ec-0.51 eV) which are also commonly present in the MBE layer on GaAs. Two traps are produced by RTP in the layer on GaAs, and one of them is identified with EL2 (Ec-0.81 eV) and another one with the activation energy of 0.49 eV is labelled NC2. On the other hand, four electron traps termed R1 (Ec-0.23 eV), R2 (Ec-0.40 eV), R3 (Ec-0.44 eV) and EL2h (Ec-0.79 eV) are produced by RTP in the layer on Si. The trap EL2h is one of an EL2 family characterised by the persistent photocapacitance quenching effect. The EL2h concentration is consistent with the EL2 concentration produced by RTP in the surface region (

In the course of our studies on the isoxazole series, a new base-induced conversion of 1,3-bis(5′-methyl-3′-isozaxolyl)triazene (IIa) into 2-(5′-methyl-3′-isoxazolyl)-5-acetonyltetrazole (IIIa) has been encountered. This reaction has been extended to 3-(m- and p-nitrophenyldiazoamino)-5-methylisoxazoles (IIb and IIc), which undergo similar conversion into 2-(m- and p-nitrophenyl)-5-acetonyltetrazoles (IIIb and IIIc), respectively. These 5-acetonyltetrazoles have been oxidized to the corresponding 5-tetrazolecarboxylic acids (IVa, IVb and IVc).

A new base-induced conversion of N-(5-methyl-3-isoxazolyl)-N-arylformamidines (IIIa–e) into 1-aryl-3-acetonyl-1,2,4-triazoles (IVa–e) has been explored. The relevant 1-aryl-3-triazolecarboxylic acids (Va–e) and some of their derivatives have been prepared.

Plasma parameters in the He-CdI 2 positive column used for an I+ laser were measured using a probe. The presence of iodine seems to partially cancel the influence on the electron temperature of the Penning process which is very dominant in the He-Cd positive column.

Our hepatic assist system consists of a combination of hemo-perfusion (200Gm of bead-type charcoal coated with 0.5μm collodion in a column) and hemodialysis against 35 liters of acetate-free recirculating dialysate. Totally, 55 perfusions have been performed in 15 patients with acute liver failure (viral hepatitis 13, and halothan-associated 2) and 3 patients with post-hepatic cirrhosis (1 with porto-caval shunt). The most frequently treated patient underwent 9 perfusions, each for 3 hours. Of the above 15 patients, 6 patients partially recovered consciousness. The EEG findings after hemoperfusion improved in 3 patients, remained unchanged in 3 and were impaired in 3. Three patients with acute liver failure has survived. Complications in the other 12 patients were; G.I. bleeding 5, renal failure 2, respiratory failure 3, and cerebral edema 4. The total plasma amino acids had been 245.1mg/100ml (normal control 47.1mg/100ml) on an average, and they decreased by 26.2% after hemoperfusion. The total amino acids in cerebro-spinal fluid (CSF) was 81.9mg/ml (normal control 7.8mg/100ml) on an average, in which glutamine, methionine, tyrosin and phenylalanine were significantly high. The total CSF amino acids soon after perfusion decreased by 4.1%. And, in patients with improved EEG grades, the total CSF amino acids were further lowered by 18.2%in 5 hours.

Isoxazolium-Salze (I) reagieren mit Grignardverbindungen (II) zu den 4-Isoxazolinen (IIIa)-(IIIg); in einigen Fallen werden zusatzlich die Spaltprodukte (IV) isoliert.

(F. E. Luborsky, J.J. Becker, and R.O. McCary, IEEE Trans. Magn. MAG-H, 1644 (1975). 5R.C. O'Handley, L.I. Mendelsohn, R. Hasegawa, R. Ray, and S. Kavesh (unpublished). 6L. A. Davis, R. Ray, C. -P. Chou, and R. C. 0' Handley (unpublished) • TR. Hasegawa, AlP Conf. Proc. 29, 216-217 (1975). 8The domain patterns observed on the unpolished and the polished samples are quite similar, indicating that the polishing adopted here does not affect the magnetic proper­ties of the samples. ST. Mizoguchi, K. Yamauchi, and H. M1yajima, inAmor­

Evidence has been presented; The degree of fat droplets was changed liver discases and fatty metamorphosis was correlated with some liver function tests