Illumination enhances methane production from thermophilic anaerobic digestion

Incandescent lamp illumination enhanced methane production from a thermophilic anaerobic digestion reactor (55 degrees C) supplied with glucose. After 10 days of operation, the volume of methane produced from light reactors was approximately 2.5 times higher than that from dark reactors. A comparison of the carbon balance between light and dark conditions showed that methane produced from hydrogen and carbon dioxide in the light reactors was higher than that from the dark reactors. When hydrogen or acetate was fed into the reactors, methane production with added hydrogen was faster and higher under light conditions than under dark conditions. The use of blue light-emitting diodes also enhanced methane production over that under dark conditions. The 16S rRNA gene copy numbers for Methanothermobacter spp. in the light reactor and in the dark reactor were at the same level. The copy number for Methanosarcina spp. in the light reactors was approximately double than that in the dark reactors. These results suggest that blue light enhances the methanogenic activity of hydrogenotrophic methanogens.

Phylogenetic description of immobilized methanogenic community using real-time PCR in a fixed-bed anaerobic digester

After immobilization of anaerobes on polyurethane foam in a thermophilic, fixed-bed, anaerobic digester supplied with acetate, the results of real-time PCR analysis indicated that the major immobilized methanogenic archaea were Methanosarcina spp., and that the major free-living methanogenic archaea were Methanosarcina and Methanobacterium spp. 16S rRNA gene densities of Methanosarcina spp. and Methanobacterium spp. immobilized on the polyurethane foam were 7.6x10(9) and 2.6x10(8) copies/cm3, respectively. Immobilized methanogenic archaea could be concentrated 1000 times relative to those in the original anaerobically digested sludge from a completely mixed thermophilic digester supplied with cattle waste. On the other hand, immobilized bacteria could be concentrated only 10 times. The cell densities of the immobilized methanogenic archaea and bacteria were higher than those of the free-living methanogenic archaea and bacteria in the reactor. The results of clone analysis indicate that the major methanogenic archaea of the original thermophilic sludge are members of the order Methanomicrobiales, and that the major methanogenic archaea immobilized on the polyurethane foam are Methanosarcina spp., and those of the liquid phase are Methanobacterium spp. The results of the real time PCR analysis approximately agree with those of the clone analysis. These results indicate that real-time PCR analysis is useful for quantitatively describing methanogenic communities.

Microalgal cultivation in a solution recovered from the low-temperature catalytic gasification of the microalga

Microalgal cultivation in a solution recovered from the low-temperature catalytic gasification of the microalga itself was studied. The growth of Chlorella vulgaris in 75-300-fold diluted recovered solution containing phosphate, magnesium ions and micro-elements was comparable to that in the standard culture medium. It was suggested that C. vulgaris could use ammonium in the recovered solution as its nitrogen source and at the same time could provide a source of biomass which was recycled via gasification.

Treatment of liquid fraction separated from liquidized food waste in an upflow anaerobic sludge blanket reactor

Thermochemical liquidization as a pretreatment for anaerobic digestion of food waste was studied using a laboratory-scale upflow anaerobic sludge blanket (UASB) reactor for a period of 82 d. Model food waste (approximately 90 wt% moisture content) was thermochemically liquidized at 175 degrees C for 1 h. The liquidized food waste was separated into a solid phase (6-10 wt%) and a liquid phase (85-89 wt%). The diluted liquid phase was continuously treated by anaerobic digestion using a UASB reactor at 35 degrees C. The volumetric loading rate was increased stepwise to 6.4-7.2 g total organic carbon (TOC)/l-reactor/d. Methane production was found to be approximately 0.35-0.61 l/g-TOC removed. The range of TOC removal efficiencies was 67-69% at an influent TOC concentration of 10.1-11.1 g/l and a volumetric loading rate of 4.8-5.3 g-TOC/l-reactor/d. This treatment process using an UASB reactor could be suitable for resource recovery from food waste.

Characterization of lighted upflow anaerobic sludge blanket (LUASB) method under sulfate-rich conditions

Growth of phototrophic bacteria was induced from granules in a lighted upflow anaerobic sludge blanket (LUASB) reactor supplied with an organic-acid-based medium containing 141.7 mg S.l(-1) of SO4(2-) under light conditions (100 microE.m(-2).s(-1)). We investigated the population dynamics of phototrophic bacteria in the LUASB reactor and the performance of the LUASB reactor for wastewater treatment and poly-beta-hydroxybutyrate (PHB) production under anaerobic light and sulfate-rich conditions. In vivo absorption spectra and a colony count suggested that populations of Rhodopseudomonas palustris and Blastochloris sulfoviridis in the LUASB reactor supplied with a medium containing 574.4 mg S.l(-1) of SO4(2-) under light conditions were lower than those supplied with a medium containing 1.0 or 141.7 mg S.l(-1) of SO4(2-) under parallel conditions. Removal efficiencies of ammonium and phosphate in the LUASB reactor supplied with the medium containing 141.7 mg S.l(-1) of SO4(2-) under light conditions were higher than those under parallel conditions but without illumination. The difference in the results of runs under light or dark conditions suggested that the ammonium and phosphate ion removal efficiencies were improved by increasing the amount of phototrophic bacterial biomass in the LUASB reactor under sulfate-rich conditions. The average PHB production rates of the bacterial cells recovered from the effluent of the LUASB reactor supplied with a medium containing 141.7, 283.5 or 574.4 mg S.l(-1) of SO4(2-) were 1.0-2.9 mg.l(-1)-reactor.d(-1) and the average PHB content based on the dry bacterial biomass was 1.4-3.6%.

Ovariectomy is sufficient to accelerate spontaneous skin ageing and to stimulate ultraviolet irradiation-induced photoageing of murine skin

BACKGROUND

Wrinkling and sagging of the skin during photoageing is physiologically associated with diminished elasticity, which can be attributed to increased fibroblast-derived elastase activity. This degrades the dermal elastic fibres needed to maintain the three-dimensional structure of the skin. We previously reported that ovariectomy accelerates ultraviolet (UV)B-induced wrinkle formation in rat hind limb skin by altering the three-dimensional structure of elastic fibres.

OBJECTIVES

In this study, we used hairless mice to assess the effects of ovariectomy with or without chronic UVA or UVB radiation on sagging and wrinkling of skin, on the elasticity of skin, as well as on matrix metalloproteinase activities in the skin.

METHODS

Ovariectomies or sham operations were performed on 6-week-old female ICR/HR hairless mice.

RESULTS

Even in the ovariectomy group without UV irradiation, the skin elasticity was significantly decreased during the 3-13 weeks after ovariectomy, which was accompanied by a significant increase in elastase activity in the skin. After UVA or UVB irradiation, skin elasticity was significantly decreased to a greater extent in the ovariectomy group than in the sham operation group, and this was accompanied by a reciprocal increase in elastase activity but not in the activities of collagenases I or IV in the skin. Consistent with the decreased skin elasticity, UVA irradiation for 12 weeks elicited more marked sagging in the ovariectomy group than in the sham operation group. UVB irradiation for 12 weeks also induced more marked wrinkle formation in the ovariectomy group than in the sham operation group.

CONCLUSIONS

These results suggest that ovariectomy alone is sufficient to accelerate skin ageing and to increase UV sensitivity, which results in the further deterioration of the skin and photoageing, and may account for the accelerated skin ageing seen in postmenopausal women.

Synthesis and evaluation of novel pyrimido-acridone, -phenoxadine, and -carbazole as topoisomerase II inhibitors

As part of a series of studies to discover new topoisomerase II inhibitors, novel pyrimidoacridones, pyrimidophenoxadines, and pyrimidocarbazoles were synthesized, and in vitro and in vivo antitumor activities and DNA-protein and/or DNA-topoisomerase II cross-linking activity as an indicator of topoisomerase II-DNA cleavable complex formation were evaluated. The pyrimidocarbazoles possessed high in vitro and in vivo potencies. Compound 26 (ER-37326), 8-acetyl-2-[2-(dimethylamino)ethyl]-1H-pyrimido[5,6,1-jk]carbazole-1,3(2H)-dione, showed in vitro growth inhibitory activity with respective IC(50) values of 0.049 microM and 0.35 microM against mouse leukemia P388 and human oral cancer KB. In vivo, this compound inhibited the tumor growth of mouse sarcoma M5076 implanted into mice with T/C values of 42% and 13% at 3.13 and 6.25 mg/kg/d respectively without significantly affecting the body weight. In addition, compound 26 (ER-37326) increased the formation of DNA-topoisomerase II cross-linking in P388 cells.

GWT1 gene is required for inositol acylation of glycosylphosphatidylinositol anchors in yeast

Glycosylphosphatidylinositol (GPI) is a conserved post-translational modification to anchor cell surface proteins to plasma membrane in all eukaryotes. In yeast, GPI mediates cross-linking of cell wall mannoproteins to beta1,6-glucan. We reported previously that the GWT1 gene product is a target of the novel anti-fungal compound, 1-[4-butylbenzyl]isoquinoline, that inhibits cell wall localization of GPI-anchored mannoproteins in Saccharomyces cerevisiae (Tsukahara, K., Hata, K., Sagane, K., Watanabe, N., Kuromitsu, J., Kai, J., Tsuchiya, M., Ohba, F., Jigami, Y., Yoshimatsu, K., and Nagasu, T. (2003) Mol. Microbiol. 48, 1029-1042). In the present study, to analyze the function of the Gwt1 protein, we isolated temperature-sensitive gwt1 mutants. The gwt1 cells were normal in transport of invertase and carboxypeptidase Y but were delayed in transport of GPI-anchored protein, Gas1p, and were defective in its maturation from the endoplasmic reticulum to the Golgi. The incorporation of inositol into GPI-anchored proteins was reduced in gwt1 mutant, indicating involvement of GWT1 in GPI biosynthesis. We analyzed the early steps of GPI biosynthesis in vitro by using membranes prepared from gwt1 and Deltagwt1 cells. The synthetic activity of GlcN-(acyl)PI from GlcN-PI was defective in these cells, whereas Deltagwt1 cells harboring GWT1 gene restored the activity, indicating that GWT1 is required for acylation of inositol during the GPI synthetic pathway. We further cloned GWT1 homologues in other yeasts, Cryptococcus neoformans and Schizosaccharomyces pombe, and confirmed that the specificity of acyl-CoA in inositol acylation, as reported in studies of endogenous membranes (Franzot, S. P., and Doering, T. L. (1999) Biochem. J. 340, 25-32), is due to the properties of Gwt1p itself and not to other membrane components.

Medicinal genetics approach towards identifying the molecular target of a novel inhibitor of fungal cell wall assembly

Glycosylphosphatidylinositol (GPI)-anchored cell wall mannoproteins are required for the adhesion of pathogenic fungi, such as Candida albicans, to human epithelium. Small molecular inhibitors of the cell surface presentation of GPI-anchored mannoproteins would be promising candidate drugs to block the establishment of fungal infections. Here, we describe a medicinal genetics approach to identifying the gene encoding a novel target protein that is required for the localization of GPI-anchored cell wall mannoproteins. By means of a yeast cell-based screening procedure, we discovered a compound, 1-[4-butylbenzyl]isoquinoline (BIQ), that inhibits cell wall localization of GPI-anchored mannoproteins in Saccharomyces cerevisiae. Treatment of C. albicans cells with this compound resulted in reduced adherence to a rat intestine epithelial cell monolayer. A previously uncharacterized gene YJL091c, named GWT1, was cloned as a dosage-dependent suppressor of the BIQ-induced phenotypes. GWT1 knock-out cells showed similar phenotypes to BIQ-treated wild-type cells in terms of cell wall structure and transcriptional profiles. Two different mutants resistant to BIQ each contained a single missense mutation in the coding region of the GWT1 gene. These results all suggest that the GWT1 gene product is the primary target of the compound.

Removal of 3-chlorobenzoate using an upflow anaerobic sludge blanket reactor under light conditions

The possibility of 3-chlorobenzoate removal from water using an upflow anaerobic sludge blanket (UASB) reactor without the addition of any extra dechlorinating culture under light conditions has been studied on a laboratory scale. Benzoate removal was observed in the first three months of operation under light conditions, but the 3-chlorobenzoate removal was not observed. After three months of operation under light conditions, the 3-chlorobenzoate concentration in the UASB reactor effluent gradually decreased to less than 1 mg x h(-1). The 3-chlorobenzoate concentration in the effluent did not increase under dark conditions. The DOC concentration in the effluent decreased according to the removal of the 3-chlorobenzoate by the UASB granules. These results indicated that granules in the UASB reactor provided the 3-chlorobenzoate removability after 80-100 d of adaptation to the 3-chlorobenzoate, and that the UASB reactor is useful for 3-chlorobenzoate removal.

Anticancer agent E7070 inhibits amino acid and uracil transport in fission yeast

E7070 is a novel sulfonamide anticancer agent that inhibits cell cycle progression in G1 in mammalian cells, but its action targets are not known. We recently employed the genetically amenable fission yeast Schizosaccharomyces pombe as a model organism to search for its targets. Here, we show that E7070 inhibits imports of amino acid and uracil into S. pombe cells. Unlike their prototrophic counterparts, leucine- and uracil-auxotrophic strains are sensitive to E7070 and are unable to proliferate with a delayed G1-S transition in low-glucose yeast extract-polypeptone medium containing this drug because this chemical markedly inhibits the uptake of leucine and uracil in low glucose medium. Furthermore, addition of leucine or uracil to the culture medium or overexpression of genes encoding an amino acid or uracil transporter suppresses the E7070-imposed growth inhibition of these auxotrophic strains. Thus, some of the molecular targets for E7070 action in S. pombe are likely to be leucine and uracil transporters.

Diurnal variation affects age-related profile in skin thickness

We have previously demonstrated that over the course of each day there are changes in skin thickness that can be measured by B-mode ultrasonography. This suggests that there is a shift in dermal fluid from the face toward the legs by gravity, resulting in a diurnal variation in skin thickness. Therefore, age-dependent profiles in skin thickness were evaluated by B-mode ultrasonography in the morning or in the afternoon for 130 normal Japanese females aged 18-83 years. Three areas of the face (the forehead, the corners of the eye, and the cheeks) were measured as distinctively sun-exposed areas while the flexion side of the forearm was measured as a weakly sun-exposed area. A weak correlation between skin thickness and age was found in all areas measured (positive for the forehead, the corners of the eye, and the cheeks; negative for forearms) in the morning but not in the afternoon, when only a weak positive correlation was observed in the cheek. These results indicate that when measuring skin thickness, an appropriate time for taking measurements should be selected with consideration of the movements of dermal fluid over the course of each day.

Low-dose tissue plasminogen activator followed by planned rescue angioplasty reduces time to reperfusion for acute myocardial infarction treated at community hospitals

The time from admission to reperfusion in patients with acute myocardial infarction (AMI) was compared according to the type of hospital and treatment strategy. A total of 164 patients with a first AMI within 12h of onset were enrolled at one tertiary emergency center (TEC) and 6 community hospitals (CHs). The subjects were randomly assigned to receive either primary percutaneous transluminal coronary angioplasty (PTCA) (TEC-primary PTCA and CHs-primary PTCA groups) or 800,000 units of intravenous monteplase, half the standard dose of a mutant tissue plasminogen activator (t-PA), followed by rescue PTCA if the Thrombolysis in Myocardial Infarction (TIMI) flow grade was 2 or less (TEC-monteplase and CHs-monteplase groups) on the first coronary angiogram. Sixty minutes after admission, TIMI flow grade 3 rates of the study groups were as follows, in descending order: TEC-monteplase group, CHs-monteplase group, TEC-primary PTCA group, and CHs-primary PTCA group (56%, 41%, 36%, and 8%, respectively; p<0.01). However, there was no significant difference in the final TIMI flow grade 3 rate among the 4 groups. In the CHs, the peak creatine kinase tended to be lower in the monteplase group than in the primary PTCA group. The results suggest that low-dose monteplase followed by rescue PTCA is an effective strategy for promoting early reperfusion in patients with AMI, especially those who are treated at CHs.

Dermal fluid translocation is an important determinant of the diurnal variation in human skin thickness

BACKGROUND

Ultrasonography has been used as a non-invasive approach to measure skin thickness. To date there have been no studies on diurnal variations in skin thickness.

OBJECTIVES

To evaluate diurnal variations in skin thickness and to compare these with corresponding echogenicity and skin elasticity.

METHODS

Measurements by ultrasonography B-mode and by Cutometer SEM 575 were carried out in the morning and in the afternoon on 20 men and 20 women (mean age 30 years) on three areas of the face (forehead, corner of the eye and cheek), the forearm and the upper arm, and the flank, thigh and calf.

RESULTS

From the morning to the afternoon, the skin thickness in both sexes significantly decreased on three areas of the face, the forearm and the upper arm, but significantly increased on the thigh and calf. In parallel, the echogenicity significantly increased from the morning to the afternoon on the three areas of the face, the forearm and the upper arm, but decreased significantly on the thigh and calf. Measurements of mechanical properties at four sites demonstrated that from the morning to the afternoon, the major parameters of skin elasticity Ue* and Uf* increased significantly in both sexes on two areas of the face and slightly on the forearm, but decreased significantly on the calf.

CONCLUSIONS

The diurnal profiles of skin thickness and skin elasticity in the upper half of the body are the reverse of those in the lower half of the body. These findings suggest that shifts of dermal fluid from the face to the leg by gravity during the day cause the diurnal variation in skin thickness.

Selective inhibition of skin fibroblast elastase elicits a concentration-dependent prevention of ultraviolet B-induced wrinkle formation

We previously reported that wrinkle formation in the skin following long-term ultraviolet B irradiation is accompanied by decreases in skin elasticity and the curling of elastic fibers in the dermis. We further showed that wrinkles could be repaired by treatment with retinoic acid and that this was concomitant with the recovery of skin elasticity ascribed to the repair of damaged elastic fibers. Those studies suggested that decreasing the tortuosity of dermal elastic fibers is an important factor involved in inhibiting or repairing wrinkle formation. Therefore, it is of particular interest to determine whether the inhibition of elastase activity in vivo would prevent the damage of dermal elastic fibers and might abolish wrinkle formation associated with the loss of skin elasticity. Because the major elastase in the skin under noninflammatory conditions is skin fibroblast elastase, we used a specific inhibitor of that enzyme to assess its biologic role in wrinkle formation. The hind limb skins of Sprague-Dawley rats were irradiated with ultraviolet B at a suberythemal dose three times a week for 6 wk. During that period, 0.1-10.0 mM N-phenetylphosphonyl-leucyl-tryptophane, an inhibitor of skin fibroblast elastase, was applied topically five times a week. N-phenetylphosphonyl-leucyl-tryptophane application at concentrations of 0.1-1.0 mM abolished wrinkle formation in a concentration-dependent manner, with a peak for inhibition at 1.0 mM. This inhibition was accompanied by a continued low tortuosity of dermal elastic fibers and a maintenance of skin elasticity. Measurement of elastase activity after 6 wk of ultraviolet B irradiation demonstrated that whereas phosphoramidon-sensitive elastase activity was significantly enhanced in the ultraviolet B-exposed skin, there was no significant increase in that activity in the ultraviolet B-exposed, N-phenetylphosphonyl-leucyl-tryptophane-treated skin. These findings suggest that skin fibroblast elastase plays an essential part in the degeneration and/or tortuosity of elastic fibers induced by cumulative ultraviolet B irradiation.

Inhibitory effect of an extract of Sanguisorba officinalis L. on ultraviolet-B-induced photodamage of rat skin

We previously reported that chronic Ultraviolet-B (UVB) irradiation causes wrinkle formation, decreases skin elasticity, and damages/curls dermal elastic fibers. Those UVB-induced wrinkles can be improved by treatment with retinoic acid or with a CO2 laser which results in a recovery of skin elasticity and a repair of elastic fiber linearity. We showed further that topical application of N-phenetyl-leucyl-tryptophane, an agent that specifically inhibits fibroblast-derived elastase, immediately after UVB irradiation inhibited UVB-induced wrinkle formation, maintained skin elasticity, and inhibited changes in the three-dimensional structure of dermal elastic fibers in a dose-dependent manner. In this study, the effects of an extract of Sanguisorba officinalis L., which also inhibits fibroblast-derived elastase, was evaluated for possible inhibition of UVB induced wrinkle formation, maintenance of skin elasticity, and prevention of damage to the 3-dimensional structure of dermal elastic fibers. Hind limb skins of 3-week-old Sprague-Dawley rats were irradiated with UVB at a suberythemal dose 3 times a week for 6 weeks. Simultaneously, an extract of Sanguisorba officinalis L. (at 0.2% (v/v) or 1% (v/v)) was topically applied 5 times per week immediately following each UVB irradiation and 1 d later. The extract of Sanguisorba officinalis L. inhibited wrinkle formation, maintained skin elasticity, and inhibited the decrease of dermal elastic fiber linearity in the rat hind limb skin in a dose-dependent manner. We have confirmed that the inhibition of elastase activity in fibroblasts immediately after UVB irradiation using an extract of Sanguisorba officinalis L. prevents chronic photodamage following UVB irradiation.