Search

We previously reported that oral administration of heat-killed Lactococcus lactis H61 improves certain human skin properties. For topical application of this strain, we reasoned that a bacterial cell extract obtained with an aqueous solvent could be readily formulated as a cosmetic ingredient. In the present study, we characterized the water extract from heat-killed H61. The extract had inhibitory activity for angiotensin-converting enzyme, which is known as suppression of inflammation of skin, and absorbed electromagnetic radiation in the UVB range. UVB-irradiated normal human epidermal keratinocytes (NHEKs) had lower viability than nonirradiated NHEKs. The NHEK survival rate was significantly higher in cells treated with the extract at 10 mg dried cells per ml prior to UVB exposure than in untreated cells or cells treated with lower extract concentrations. At this concentration, the extract also inhibited the production of interleukin-8 induced by UVB. The extract did not protect against hydrogen peroxide-induced cell damage. These data indicate that topical application of the H61 extract alleviates UVB damage and reduces inflammation in skin cells. The present study expands the potential application of strain H61 to its use as a cosmetic ingredient in addition to its use in the food industry. SIGNIFICANCE AND IMPACT OF THE STUDY: In our previous report, oral administration of heat-killed Lactococcus lactis H61 improved certain human skin properties. This study aimed exploring the potential topical use of this strain. The water extract derived from heat-killed cells with angiotensin-converting enzyme inhibitory activity, which is known as suppression of inflammation of skin, could protect normal human epidermal keratinocytes (NHEKs) from damage caused by UVB. Higher interleukin-8 production by UVB-exposed NHEKs than nontreated cells was suppressed by addition of the extract. The extract absorbed electromagnetic radiation in the UVB range. This extract could help in the maintenance of skin health by suppressing inflammation.

A substrate-binding-state mimic of H2O2-dependent cytochrome P450 that is able to catalyze monooxygenation of non-native substrates was constructed by one-point mutagenesis of P450SPα (CYP152B1). P450SPα, a long-alkyl-chain fatty acid hydroxylase, lacks any general acid–base residue around the heme. The carboxylate group of a fatty acid is thus indispensable for the generation of active species using H2O2. We prepared an A245E mutant to mimic a substrate-binding state by placing a carboxylate group at the active site. The active site structure of the A245E mutant is similar to that of the fatty-acid-bound state of P450SPα and catalyzes styrene oxidation at a rate of 280 min−1 (kcat), whereas the wild-type enzyme does not show any catalytic activity. More importantly, the same mutation, i.e. the mutation of the highly conserved threonine in P450s to glutamic acid, was also effective in introducing peroxygenase activity into P450BM3, P450cam, and CYP119. These results indicate that a variety of peroxygenases based on P450s can be constructed by one-point mutagenesis.

Objective: Previously, we showed that ingestion of fermented milk made by only Lactococcus lactis strain H61 (H61-fermented milk) improves various skin properties in young Japanese women (age, around 20 y). Because the condition of human skin varies with age, we investigated the effects of H61-fermented milk on skin properties of middle-aged women. Design and setting: A randomized, double-blind trial in a clinical research setting. Participants: Healthy, middle-aged, female volunteers (n = 23; age: 36–62 y). Intervention: H61-fermented milk (1010 CFU) or conventional yogurt (1010CFU of both Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus; a reference food) was given daily for 4 weeks. Measurements: Before and at the end of the 4-week treatment, we measured skin hydration (inner forearms and cheek) and sebum content (cheek only). In addition, salivary samples were collected for analysis of immune, stress, and inflammation biomarkers. Self-questionnaires (regarding skin and general health conditions) were done at week 4. Results: By mechanical analysis, the interventions did not alter the skin properties of either group. At week 4, self-questionnaire skin scores for elasticity and texture were significantly higher; scores for darkness tended to be improved in the H61-fermented milk group than the conventional yogurt group. In the general health condition section, diarrhea was significantly more prevalent in the H61-fermented milk than in the conventional yogurt group. The intervention did not alter immunoglobulin A, cortisol, α-amylase, and C-reactive protein levels in saliva. Conclusions: According to self-questionnaires, H61-fermented milk provides beneficial effects on some skin properties of middle-aged women. This intervention would be useful for increasing the quality of life in an aging population after characterizing the beneficial effect by mechanical analysis in future study.

Reactive oxygen species, such as superoxide, can damage cellular components, such as proteins, lipids, and DNA. Superoxide dismutase (SOD) enzymes catalyze the conversion of superoxide anions to hydrogen peroxide and dioxygen. SOD is present in most lactococcal bacteria, which are commonly used as starters for manufacturing fermented dairy products and may have health benefits when taken orally. We assessed the effects of carbohydrate use on SOD activity in lactococci. In Lactococcus lactis ssp. lactis G50, the SOD activity of cells grown on lactose and galactose was higher than that on glucose; in Lactococcus lactis ssp. cremoris H61, SOD activity was independent of the type of carbohydrate used. We also investigated the activity of NADH oxidase, which is related to the production of superoxide in strains G50 and H61. Activity was highest in G50 cells grown on lactose, lower on galactose, and lowest on glucose, whereas activity in H61 cells did not differ with the carbohydrate source used. The SOD and NADH oxidase activities of strain G50 in three carbohydrates were linked. Strain G50 fermented lactose and galactose to lactate, acetate, formate, and ethanol (mixed-acid fermentation) and fermented glucose to mainly lactate (homolactic fermentation). Strain H61 fermented glucose, lactose, and galactose to mainly lactate (homolactic fermentation). In strain G50, when growth efficiency was reduced by adding a metabolic inhibitor to the growth medium, SOD activity was higher than in the control; however, the metabolism was homofermentative. Aerobic conditions, but not glucose-limited conditions, increased SOD activity, and mixed-acid fermentation occurred. We conclude that the effect of carbohydrate on SOD activity in lactococci is strain dependent and that the activity of commercial lactococci can be enhanced through carbohydrate selection for mixed-acid fermentation or by changing the energy distribution, thus enhancing the value of the starter and the resulting dairy products.

It has recently been reported that the rare sugar d-allulose has beneficial effects, including the suppression of postprandial blood glucose elevation in humans, and can be substituted for sucrose as a low-calorie food ingredient. To examine the applications of d-allulose in the dairy industry, we investigated the effects of d-allulose on the acid production of 8 strains of yogurt starter (Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus) and 4 strains of lactococci, including potential probiotic candidates derived from dairy products. Acid production by 2 L. delbrueckii ssp. bulgaricus yogurt starter strains in milk was suppressed by d-allulose, but this phenomenon was also observed in some strains with another sugar (xylose), a sugar alcohol (sorbitol), or both. In contrast, among the dairy probiotic candidates, Lactococcus lactis H61, which has beneficial effects for human skin when drunk as part of fermented milk, was the only strain that showed suppression of acid production in the presence of d-allulose. Strain H61 did not metabolize d-allulose. We did not observe suppression of acid production by strain H61 with the addition of xylose or sorbitol, and xylose and sorbitol were not metabolized by strain H61. The acid production of strain H61 after culture in a constituted medium (tryptone-yeast extract-glucose broth) was also suppressed with the addition of d-allulose, but growth efficiency and sugar fermentation style were not altered. Probiotic activities-such as the angiotensin-converting enzyme inhibitory activity of H61-fermented milk and the superoxide dismutase activity of H61 cells grown in tryptone-yeast extract-glucose broth-were not affected by d-allulose. d-Allulose may suppress acid production in certain lactic acid bacteria without altering their probiotic activity. It may be useful for developing new probiotic dairy products from probiotic strains such as Lactococcus lactis H61.

Many milk fermentations use mixed cultures of lactic acid bacteria. To select a new mixed starter culture, 100 acid-producing bacterial strains were isolated from raw cow milk. Of these, 13 strains identified as belonging to the genera Lactococcus, Lactobacillus, Leuconostoc, or Weissella (based on phenotypic and genotypic tests) were assessed for a symbiotic effect between pairs of isolated strains during growth in milk. Among the strains tested, a mixed culture of Lactococcus lactis ssp. lactis strain 54 and Lactococcus raffinolactis strain 37 stimulated greater acid production during fermentation than occurred with pure fermentation. This stimulatory effect was not observed in milk supplemented with yeast extract or glucose or in constituted medium. Addition of a cell-free filtrate from milk fermented by strain 54 increased acid production by strain 37; however, the converse effect was not observed. The increased acid production by this mixed culture was, therefore, due to stimulation of strain 37 by metabolic products of strain 54, suggesting that the interaction between strains 54 and 37 is commensal. Analysis with a taste-sensing system indicated that fermented milk containing the mixed culture was more acidic, had more anionic bitterness, had greater aftertastes of anionic bitterness and astringency, and was less salty and umami than milk containing the individual cultures. This study identifies a new commensal relationship between 2 lactococcal strains that are commonly used for making dairy products.

An automatic measuring system for the partial pressure, pCO2, of atmospheric and oceanic carbon dioxide was developed. The system was mounted on a moored buoy for routine observation of maritime meteorology in the East China Sea. CO2 observations were conducted from June 29, 1997 to January 6, 1998. During the observation period, the atmospheric pCO2 showed little variation (341–365 μatm), whereas pCO2 in the surface water varied significantly (308–408 μatm). In the summer, pCO2 was higher in the surface water than in the overlying atmosphere, implying that this area was a source for atmospheric CO2, though it became a sink after late September. Time-series data clearly exhibited significant short-term variations in the oceanic pCO2, i.e. sudden variations during the passage of typhoons, and diurnal variations driven by the diurnal variations in the sea-surface temperature under calm conditions. The effects of typhoons on ocean–atmosphere CO2 exchange at the surface could differ, depending on the relative position of the mooring site with respect to the center of the moving typhoons. These differences result from the different contributions of sea-surface cooling, entrainment, and upwelling. The efflux enhanced by three typhoons accounted for 60% of the efflux of CO2 in the warm season. It is suggested that typhoons have a significant impact on the carbon cycle in the western subtropical North Pacific.

Hydrogen bonding in aqueous N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMA) solutions was studied by Raman spectroscopy of the OH-stretching spectra of water as functions of solute concentration and temperature (from –50 to 50 °C). The Raman spectra were decomposed successfully into two components (the low- and high-frequency components). The peak area ratio of the low-frequency component to the high-frequency component increases exponentially with decreasing temperature. The frequency of the low-frequency component decreases linearly with lowering temperature down to –50 °C at all solute concentrations (solute mol fraction from 0.3 to 0.7). It is shown that the hydrogen bonds in the clathrate structures around DMA molecules are stronger than those around DMF molecules.Key words: Raman spectrum, DMF, DMA, aqueous solution, low temperature.

Aims: The aim of this study is to clarify the effect of Tween 80 on bile tolerance of lactococci. Methods and Results: Four out of the six strains of lactococci could grow in broth containing 0·3% bile in the presence of 1% Tween 80, but grew slightly or not at all in the absence of Tween 80. Growing with Tween 80 altered the fatty acid composition of all three strains tested, but it is not clear which fatty acid influences bile tolerance. Material that absorbed light at 260 nm leaked from the cells tested with bile, but the leakage was decreased by addition of 1% Tween 80. Coincidentally, the decrease in the cell count by exposure to bile was suppressed by addition of Tween 80. Conclusions: Tween 80 enhances bile tolerance of some strains of lactococci. Significance and Impact of the Study: It is clarified that Tween 80 in the broth contributes to the bile tolerance of lactococci by reducing the cellular leakage caused by bile.

Chemical measurements made in the northern North Pacific from a commercial volunteer observing ship (VOS) program during March 1995–March 1998 are presented. Quasi-continuous measurements of the fugacity of CO2 (fCO2, which takes into account the nonideal nature of the gas; the values are within 0.5–1.5 μatm of the partial pressure in surface water) in seawater were made from two independent systems with different designs, and those results are emphasized here. One system used a fast response bubbling equilibrator with measurements each minute; the other system used a showerhead equilibrator with hourly measurements. Comparison of the results from these side-by-side systems provides useful information about the requirements for making high quality measurements of surface seawater and atmospheric fCO2. From this comparison, the fast response system is deemed to be more stable and potentially more accurate. The utility of this system in waters with high spatial variability is also demonstrated. Fac...

We conducted a randomized double-blind trial to evaluate the effects of fermented milk produced using only Lactococcus lactis strain H61 as a starter bacterium (H61-fermented milk) on the general health and various skin properties of young women. Healthy female volunteers (n=23; age=19-21r) received H61-fermented milk (10(10) cfu of strain H61/d) or conventional yogurt (10(10) cfu of both Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus per day), as a reference food, daily for 4 wk. Before and at the end of 4 wk, blood samples were taken, and skin hydration (inner forearms and cheek) and melanin content, elasticity, and sebum content (cheek only) were measured. Skin hydration at the inner forearm was higher at wk 4 than at wk 0 in both groups. Sebum content in cheek rose significantly after intervention in the H61-fermented milk group, but not the conventional yogurt group. Other skin parameters did not differ in either group. Serum analysis showed that total protein concentration and platelet count were elevated and reactive oxygen species decreased in both groups after the intervention. Although H61-fermented milk and conventional yogurt had similar effects on skin status and some blood characteristics of participants, an increase of sebum content in cheek is preferable to H61-fermented milk. As skin lipids contribute to maintaining the skin barrier, H61-fermented milk would provide beneficial effects on skin for young women.

Racemic 4,4,4-trifluoro-3-(indole-3-)butyric acid (TFIBA) has been synthesized and shown to inhibitAvena coleoptile elongation. (S)-(+)-TFIBA (fig. 1), which was prepared by an enzymatic method and markedly promotes root growth of Chinese cabbage, lettuce and rice plants, is a novel fluorinated plant growth regulator. Activity of the (S)-(+)-enantiomer of TFIBA was 10-fold greater than that of the (R)-(−)-enantiomer in the first two plant species and 5-fold greater in rice.

To exert their beneficial effects, probiotics need to survive in the stringent conditions of the gastrointestinal tract. Symbiosis between different bacteria is a potential way of enhancing this survival. In developing new probiotic cultures, we investigated the synergic effect between Enterococcus mundtii IFO 13712 and 7 strains of Lactococcus lactis, many of which are widely used as starter bacteria for making dairy products and have probiotic properties. The growth yield of a mixed culture of L. lactis strain Y and IFO 13712 in de Man, Rogosa, and Sharpe broth was greater than that of a single culture. Supernatant from culture of strain IFO 13712 enhanced the growth of strain Y, but that of strain Y did not enhance the growth of strain IFO 13712. This commensalism phenomenon was confirmed by using a simpler tryptone-yeast extract-glucose (TYG) broth. Increased cell yield in mixed culture of the 2 strains compared with single cultures was observed in TYG broth in the presence of both Tween 80 and citrate but not in TYG broth alone or TYG broth containing either Tween 80 or citrate. Thus, the Tween 80 and citrate in the broth contributed to the commensalism. Metabolite analysis revealed that ethanol production in the co-metabolism of glucose and citrate by strain Y was suppressed by mixed culture in TYG broth containing Tween 80 and citrate, compared with that in TYG broth containing citrate alone. The mechanism supporting the observed commensal symbiosis between strains Y and IFO 13712 was the increase in availability of glucose for lactate production by strain Y because, in glycolysis, the pathway from glucose to lactate is energic, whereas the pathway from glucose to ethanol is not. Whether growth stimulation of strain Y by mixing it with IFO 13712 in milk products will enhance the survival of strain Y in the intestine remains to be elucidated.

Lactococcus lactis H61 can increase the cellular immune responses of aged (14-mo-old) senescence-accelerated mice. The aim of this study was to investigate the factors contributing to IL-12 induction by strain H61 by analyzing strains derived from it. Strain H61 derivative no. 13 was obtained by growing the parent strain at 37°C. This derivative induced significantly lower production of IL-12 from J774.1 macrophage cells than did the parent strain H61. The 2 strains differed in the resistance of their whole cells or cell walls to lysozyme, a cell wall-degrading enzyme. Sodium hydroxide treatment to de-O-acetylate muramic acid in the cell walls of the 2 strains reduced the lysozyme resistance, compared with untreated cell walls: at 3h after adding lysozyme, the lysozyme resistance of untreated and NaOH treated cell wall from strain H61 was 55.4% and 11.7%, respectively. The values of untreated and NaOH-treated cell walls from strain no.13 were 73.7 and 42.8%, respectively. The reduction was higher in strain H61, indicating that the cell walls of strain H61 were highly O-acetylated. Trichloroacetic acid treatment to remove wall-associated polymers such as teichoic acids made the lysozyme resistance of the cell walls of both strains similar. The sugar content of cell walls prepared from strain H61 was significantly higher than that of strain no. 13 cell wall. A derivative with less activity for inducing IL-12 by macrophage cells had less O-acetylation and had lower sugar content in the cell wall than did strain H61. Modifying the cell wall of strain H61 may be a useful way to regulate its ability to induce IL-12. Strain H61 has been used as a starter bacterium in the dairy industry. This study could lead to enhancing the value of dairy products made by strain H61 by characterizing the key factor(s) responsible for its stimulation of immunity.

The IL-12-inducing ability of lactic acid bacteria could be a critical index of immunomodulatory activity, especially in promoting T-helper-1 responses and in suppressing T-helper-2-mediated allergic responses. We aimed to develop a simple method for enhancing the IL-12-inducing ability of bacteria. We examined the in vitro effects of strains of lysozyme-modified Lactococcus (ML-LYS), prepared by heat treatment of the Lactococcus strain in the presence of lysozyme, on the ability of mouse macrophage-like J774.1 cells and spleen cells to produce IL-12. An IL-12-inducing ability greater than that of heat-killed bacteria was shown by 41 of 46 ML-LYS strains in J774.1 cells and by all 46 ML-LYS strains in mouse spleen cells. In contrast, bacteria modified by α-lactalbumin, β-lactoglobulin, or ovalbumin did not enhance IL-12 production in J774.1 cells. Microscopically, ML-LYS showed stronger resistance to lysozyme and macrophage digestion than did heat-killed bacteria or the other modified bacteria. Addition of chitotriose, a lysozyme inhibitor, enhanced IL-12 production by J774.1 cells stimulated with heat-killed bacteria. Therefore, enhancement of resistance to lysozyme may be a key factor in the strong IL-12-inducing ability of ML-LYS. These findings have important implications for the design of dairy products that have an immunomodulatory effect using the modified bacteria.

The factors of bile tolerance (as one among the fundamental characteristics of probiotic bacteria) were determined in lactococci by using plasmid variants. Bile tolerance of Lactococcus lactis wild-type (WT) strains 527 and N7 (determined by viability counts on bile-containing agar) was equivalent to the corresponding plasmid-free derivatives. In contrast, L. lactis WT strain DRC1 had lower bile tolerance than its plasmid-free derivative DRC1021. Plasmid pDR1-1B, extracted from strain DRC1, was introduced into strain DRC1021 by co-transformation with the vector plasmid pGKV21 as an indicator. Strain DRC121 (DRC1021 harboring pGKV21) had good bile tolerance as did strain DRC1021, while strain DRC13 (DRC1021 harboring both pDR1-1B and pGKV21) did not. Fatty acid (FA) composition was different between strains DRC121 and DRC13. The plasmid pDR1-1B or plasmid profile and FA composition are key factors for bile tolerance of strain DRC1, and therefore changing the plasmid profile might be a way of modulating bile tolerance in lactococci.

Lactococcus lactis subsp. lactis G50 has immunomodulatory activity and is a candidate for use as a probiotic strain. We investigated the factors that affect the immunomodulatory activity of this strain. The macrophage-like cell line J774.1A was exposed to live or dead cells of strain G50 grown in different media, and the interleukin (IL) 12 produced by the cell line was then measured. Live cells grown in M17 supplemented with glucose (GM17 cells) induced IL-12 production by J774.1 cells significantly more than did cells grown in deMan Rogosa Sharpe (MRS) broth (MRS cells; P < 0.05). In the case of dead cells, the opposite results were obtained in these two samples. The sugar content of GM17 cells was significantly higher than that of MRS cells (P < 0.01). The fatty acid compositions of GM17 cells and MRS cells differed. Lysis of GM17 cells by lysozyme, which degrades the cell wall, was greater than in MRS cells. The cell wall fraction prepared from GM17 cells induced significantly more IL-12 production than did the fraction from MRS cells (P < 0.05). These results indicated that alterations in cellular components or in the structure of the cell surface by the growth media affected the immunomodulatory activity of strain G50. Attention should be paid to the selection of growth medium in testing for the immunomodulatory activity of lactic acid bacteria.

Uterine leiomyosarcoma occurring spontaneously in a domestic golden hamster was examined histologically and immunohistochemically. The histological findings for this tumour were similar to those for leiomyosarcomas described in other species. Immunohistochemical examination demonstrated the positivity of neoplastic cells with alpha-smooth muscle actin and desmin. From the results mentioned above, the tumour of this case was revealed to be of smooth muscle origin. To our knowledge, this is the first report of a uterine leiomyosarcoma in domestic golden hamsters.

Aims: The aim of this study was to obtain new Lactococcus lactis strains from nondairy materials for use as milk fermentation starters. The genetic and phenotypic traits of the obtained strains were characterized and compared with those of L. lactis strains derived from milk. It was confirmed that the plant-derived bacteria could be used as milk fermentation starters. Methods and Results: About 2600 lactic acid bacteria were subjected to screening for L. lactis with species-specific PCR. Specific DNA amplification was observed in 106 isolates. Forty-one strains were selected, including 30 strains of milk-derived and 11 of plant-derived, and their phenotypic traits and genetic profiles were determined. The plant-derived strains showed tolerance for high salt concentration and high pH value, and fermented many more kinds of carbohydrates than the milk-derived strains. There were no remarkable differences in the profiles of enzymes, such as lipases, peptidases and phosphatases. Isolates were investigated by cluster analysis based on randomly amplified polymorphic DNA profiles. There were no significant differences between isolates from milk and those from plant. The L. lactis subsp. cremoris strains were clustered into two distinct groups, one composed of the strains having the typical cremoris phenotype and the other composed of strains having a phenotype similar to subsp. lactis. Fermented milk manufactured using the plant-derived strains were not inferior in flavour to that manufactured using the milk-derived strains. Conclusions: Plant-derived L. lactis strains are genetically close to milk-derived strains but have various additional capabilities, such as the ability to ferment many additional kinds of carbohydrates and greater stress-tolerance compared with the milk-derived strains. Significance and Impact of the Study: The lactic acid bacteria obtained from plants in this study may be applicable for use in the dairy product industry.

A high-speed X-address decoding scheme with wired-OR bipolar predecoders and partial decoding level converters is presented. In addition, a sensing scheme with small signal voltage swing (particularly for read bus lines) is described. These two high-speed schemes and a double-level polysilicon layer, double-level metal layer, 0.8- mu m BiCMOS process technology were used to implement a 5-ns address access time, 1-W power dissipation, and 1-Mb emitter-coupled logic input/output (I/O) interface SRAM (static random-access memory). >

The purpose of the present study was to evaluate the effect of intravenous albumin administration on the serum total and unbound bilirubin values in term non-hemolytic hyperbilirubinemic neonates during intensive phototherapy.Fifty-eight infants (gestational age 39.4 +/- 1.4 weeks; birth weight 3,245 +/- 435 g) were given phototherapy with similar light energy. Twenty infants (control group) received only phototherapy, while 38 others (albumin-treated group) were also given human albumin at 1 g/kg bodyweight, i.v., during the first 2 h of phototherapy.When comparing changes in total and unbound bilirubin values 0, 2, 6 and 24 h after entering the study between the albumin-treated group and the control group, there was a significant reduction in the serum unbound bilirubin values at the end of albumin treatment and at 6 and 24 h. However, there was no significant reduction in total serum bilirubin values during the study period. In the albumin-treated group, the mean serum unbound bilirubin reduction from the baseline level at the end of albumin treatment and at 6 and 24 h was 0.40 +/- 0.19, 0.41 +/- 0.20 and 0.43 +/- 0.20 microg/dL, respectively.The results suggest that albumin priming may be effective for an immediate reduction in serum unbound bilirubin values, the fraction that is potentially neurotoxic.

Amination of aryl trifluoromethyl ketones with ammonium formate readily gave racemic 2,2,2-trifluoro-1-arylethylamines in good yields. Resolution of 2,2,2-trifluoro-1-phenylethylamine was carried out with the Pseudomonas fluorescens lipase via enantioselective alcoholysis of its chloroacetamide.

There have been few studies on the probiotic activity of Lactococcus strains although they are commonly used as starter bacteria in manufacturing many kinds of fermented dairy products. Nine strains of the genus Lactococcus were examined for their probiotic properties, such as adherence to human enterocyte-like Caco-2 cells and tolerance to acid and bile. Six strains were adhesive and the highest adhesion was observed with Lactcoccus lactis ssp. lactis NIAI527. This strain adhered to the microvilli of cells as observed by scanning electron microscopy and also tolerated low pH and bile. These properties should make strain 527 a potential new probiotic strain.

Nine mixed-strain starters were examined for their abilities to produce gamma-aminobutyric acid. Six commercial starters were found to produce gamma-aminobutyric acid in a skim milk culture. The bacterium that produced gamma-aminobutyric acid was isolated from the mixed-strain starters, identified as citrate-utilizing Lactococcus lactis ssp. lactis (formerly L. lactis ssp. lactis biovar diacetylactis) and designated as strain 01-7. A cell extract showed glutamate decarboxylase activity, for which the optimum pH was 4.7. In pH-controlled cultivation, gamma-aminobutyric acid was generated at pH 5.0 but not above pH 5.5. Cheeses were prepared experimentally using strain 01-7 to determine the relationship between the pH values and the production of gamma-aminobutyric acid during cheese ripening. gamma-Aminobutyric acid increased linearly in the experimental cheeses as the pH of the cheese decreased. Based on these results, gamma-aminobutyric acid was concluded to be produced by the cheese starters during ripening.

Publisher Summary This chapter presents a methodology for time-independent and time-dependent shape identification problems. The problem considered is that of determining the phase-change interface from several observed temperatures. In the present method, imaginary heat sources arranged in an imaginary domain are introduced. Then the phase-change interface is identified as the isothermal surface at the melting temperature by controlling the imaginary heat source intensities. Using the delta-function type imaginary heat sources, their corresponding Green's functions can numerically be calculated before the identification. As a result, the imaginary heat source intensities can explicitly be obtained by the least-squares method. The features of the present method in this chapter can be summarized as follows: first, by optimally controlling imaginary heat sources arranged in an imaginary domain, the temperature distribution in solid phase can be realized and phase-change interface can be determined as a contour surface of the phase-change temperature. Second, by numerically calculating Green's functions corresponding to delta-function type imaginary heat sources, the optimal heat source intensities can explicitly be determined by the least-squares method. Third, by using the symmetry of Green's functions, the imaginary heat source locations can also be optimized by a conventional optimization method without iterative numerical simulations of the heat conduction field. Fourth, Green's function converges rapidly with respect to the time. Fifth, the present method can easily be applied to nonlinear problem with temperature-dependent thermal conductivity by adopting Kirchhoff's transform.

The susceptibility of monocyte-derived cultured dendritic cells (DCs) to human immunodeficiency virus (HIV) infection and their role in viral transmission in the immune response were studied in detail. We observed that highly purified cultured DCs were infected with the T-tropic Lai strain of HIV type 1 (HIV-1Lai) via the CD4 receptor, and this was followed by formation of the complete provirus as detected by PCR. HIV mRNAs were transcribed at only low levels, and virus production was undectable; however, the addition of the purified protein derivative antigen of tuberculin and of autologous resting T cells to HIV-1Lai-infected DCs but not to HIV-1Lai-infected macrophages led to massive HIV transmission and production. These data suggest that the interaction of infected DCs with T cells during the normal immune response could play an important role in the activation and expansion of HIV.

Immunoglobulin mu chains synthesized in murine pre-B cells are known to be associated with surrogate light chains designated as omega (omega), iota (iota) and B34. In addition to these molecules, we identified the complexes of polypeptides (50, 40, 27 and 15.5 kd) associated with surface or intracellular mu chains of pre-B cell lines. Most of these polypeptides were continuously synthesized and associated with mu chains in virgin B cells lines, although some of them scarcely bound to the mu kappa dimer or mu 2 kappa 2 tetramer concomitantly present in the same clone or population. However, in mature B cells they were no longer detectable except B34. Cross-linking of micron chains on the surface of pre-B cells resulted in an increase in intracellular free Ca2+, indicating that the micron chain complex on the surface of pre-B cell lines acted as a signal transduction molecule. However, the receptor cross-linkage of pre-B cell lines did not induce the increased inositol phospholipid metabolism usually observed in virgin and mature B cell lines. These results suggest that, during the differentiation from pre-B to mature B cells, the cells express two types of mu chain complexes which exhibit different structures as a whole and possess different signal transducing capacities.

The title compound, 5,5,8,8-tetrafluoro-6-methoxy-5,8-dihydroquinoline, C 10 H 7 F 4 NO, has a planar 1,4-cyclohexadiene ring with a maximum deviation of 0.019(3) A from planarity, The C(6)=C(7) double bond [1.327(4) A] is shorter than the C(9)=C(10) double bond [1.382 (4) A], the latter value being consistent with that normally found in pyridine rings.

We performed a cytogenetic study on 140 nonpolymalformed patients with mental retardation of clinically undefined origin, using a high resolution banding technique, to determine how much chromosome abnormalities contribute to the etiology of this condition. A total of 15 patients (10.7%) were found to have autosomal or sex chromosomal abnormalities. Autosomal abnormalities included partial monosomy (5 cases), reciprocal translocation (one case), 13/14 robertsonian translocation (3 cases), unbalanced translocation (one case), inverted duplication of 15q (one case) and mosaic trisomy 21 (one case). Sex chromosomal abnormalities comprised structural rearrangement of the short arm of the X chromosome (one case) and 47, XXY in a pure or mosaic form (two cases). It should be noted that four out of the 5 cases of partial monosomy had subtle interstitial deletions, which might have been unidentified by the conventional G-banding method alone. In one case of the robertsonian translocation 46,XY,t(13;14)/45,XY,t(13;14), a small deletion was thought to have occurred in the cells with a chromosome number of 45. Comparison of clinical features of the 15 chromosomally abnormal patients with those of patients with normal karyotypes did not show any clinical parameter indicative of chromosome imbalance. These results suggest that a subtle chromosomal deletion is specific to mental retardation associated with few malformations. We believe that diagnostic evaluation of mentally retarded patients, even if nonmalformed, should include chromosome analysis using a high resolution banding technique.

Papular acrodermatitis of childhood (PAC) has recently been reported to be associated with hepatitis B surface antigen (HBsAg) subtype ayw. Between September, 1978, and June, 1979, we saw 14 patients with PAC in a small epidemic occurring in Iwakuni City, Japan. HBsAg was detected in sera from all patients. Subtyping of HBsAg in 11 patients showed that 8 had a determinant adr and 3 had no detectable determinant because of low antigen titers. The result suggests that factors other than the specific HBsAg subtype contribute to the development of PAC.

The main reason for unfavourable surgical outcome of lung cancer is latent distant metastases over looked during surgery, which ultimately cause recurrence, or death of the patients even in cases undergoing curative surgery. This fact necessitates the indispensable use of systemic adjuvant therapy in patients under going surgery for lung cancer. There have been mary reports concerning the clinical efficacy of surgical adjuvant chemotherapy for non-small cell lung cancer using various kinds of drugs in various treatment modalities, but the results have been controversial. During the past eleven years, we have used postoperative chemotherapy in three ways over three different periods: in the earliest period, short-term combined chemotherapy (STCC) was used, in the middle period, intermittent long-term combined chemotherapy (ILTCC) was used in combination with immunotherapy for a randomized group, and in the latest period, when continuous long-term combined chemotherapy (CLTCC) with immunotherapy was employed. A comparison was then made between these three kinds of treatment groups. In Comparing of the results obtained for the earliest and middle periods, ILTCC showed a significantly improved beneficial effect over STCC in terms of further increased survival rate. Furthermore, by randomized study, it was clarified that the favourable effect of ILTCC was further improved by concomitant use of immunotherapy. CLTCC with immunotherapy carried out in the latest period seemed to be prevent early recurrences in patients with stage I or II who underwent curative surgery, even though a short-term observation period of for 20 months was employed. It is conceivable that the latest treatment modality used will exerted best the most favourable beneficial effect in comparison with the two early treatments. A review of the literature was presented along with a discussion of the clinical value of chemotherapy and immunochemotherapy as a surgical adjuvant.

Alkylbenzole (I) werden unter photolytischen Bedingungen mit Hexafluorpropen (II) umgesetzt und die erhaltenen Addukte charakterisiert.