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101.
Background: Active hexose correlated compound (AHCC) (a mixture of polysaccharides, amino acids, lipids and minerals derived from cultured mycelia of a Basidiomycete mushroom, Lentinula edodes) was used to assess amelioration of alopecia (hair loss) caused by cytosine arabinoside (Ara-C) and modulation of liver injury caused by single doses 6-mercaptopurine (6-MP) plus methotrexate (MTX). Methods: Follicular integrity and hair growth was assessed in male and female SD neonatal rats (8 days old) treated with a single dose of Ara-C (30 mg/kg/day, i.p.) and AHCC (500 mg/kg/day, p.o.) for 7 consecutive days. The side effects of a single oral dose of 6-MP (2.5 mg/kg body weight) plus MTX (30 mg/kg body weight) and their amelioration by treatment with AHCC (1000 mg/kg body weight) for 28 days were assessed in male ddY mice (8 weeks old). Results: Of the Ara-C treated rats 71.4% showed severe alopecia and 28.6% showed moderate alopecia. However, the AHCC (p.o.)-treated Ara-C group was significantly protected from alopecia. Ara-C treated rats had profound loss of hair follicles but the Ara-C plus AHCC-treated group had mild losses of follicles. AHCC supplementation to the 6-MP- and MTX-treated mice significantly increased body weight, erythrocytes, leukocytes and serum albumin, improved liver hypertrophy and degeneration, normalized the activities of serum glutamic oxaloacetic transaminase (sGOT) and serum glutamic pyruvic transaminase (sGPT), and enhanced liver drug-metabolizing enzymes. Conclusion: Co-administration of AHCC significantly reduced the side effects associated with Ara-C, 6-MP and MTX. However, the molecular mechanism for AHCC activity and its clinical integrity for use needs defining.  相似文献   
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We describe a new species of dicroglossid frog of the Fejervarya limnocharis complex from western Honshu, Japan Mainland. The new species, Fejervarya kawamurai, is genetically closer to F. sakishimensis than to F. limnocharis. It differs from F. sakishimensis by smaller tympanum, head, forelimb, hindlimb, foot, and tibia lengths, all relative to snout-vent length, and from F. multistriata by relatively shorter forelimb, hindlimb, foot, and tibia. From F. limnocharis and F. iskandari, it is differentiated by relatively smaller forelimb, hindlimb, foot, and tibia lengths. Taxonomic problems of Fejervarya populations occurring in Central Ryukyus, continental China, and Taiwan are discussed.  相似文献   
105.
To elucidate the mechanism by which C4b-binding protein inhibits the cofactor activity of protein S for anticoagulant-activated protein C, the interactions between protein S, activated protein C, and C4b-binding protein were studied using solid-phase enzyme immunoassays. Both activated protein C and C4b-binding protein bound to protein S fixed to microplate wells. C4b-binding protein did not inhibit the binding of activated protein C to protein S, nor did activated protein C inhibit the binding of C4b-binding protein to protein S. Activated protein C bound to a protein S-C4b-binding protein complex which was cross-linked with a chemical reagent as well as it bound to free protein S. Protein S-C4b-binding protein complex competitively inhibited activated protein C-binding to free protein S and also the cofactor activity of free protein S. Immunoblotting analysis showed ternary complex formation with protein S, C4b-binding protein, and activated protein C in the liquid phase by treatment with the cross-linking reagent. These findings suggest that the protein S-C4b-binding protein complex inhibits the cofactor activity of free protein S probably by inhibition of functionally active protein S-activated protein C complex formation by the apparent competitive formation of an inactive ternary complex with protein S, C4b-binding protein, and activated protein C.  相似文献   
106.
Systemic acquired resistance (SAR) is a potent innate immunity system in plants that is induced through the salicylic acid-mediated pathway. N-cyanomethyl-2-chloroisonicotinamide (NCI) is able to induce a broad range of disease resistance in tobacco and rice and induces SAR marker gene expression without SA accumulation in tobacco. To clarify the detailed mode of action of NCI, we analyzed its ability to induce defense gene expression and resistance in Arabidopsis mutants that are defective in various defense signaling pathways. Wild-type Arabidopsis treated with NCI exhibited increased expression of several pathogenesis-related genes and enhanced resistance to the bacterial pathogen, Pseudomonas syringae pv. tomato DC3000. NCI induced disease resistance and PR gene expression in NahG transgenic plants, but not in the npr1 mutant. NCI could induce PR gene expression in the etr1-1, ein2-1 and jar1-1 mutants. Thus, NCI activates SAR, independently from ethylene and jasmonic acid, by stimulating the site between SA and NPR1.  相似文献   
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An endo β-1, 3-glucanase which is able to disrupt the cells of living yeast has been purified in homogeneous state from the culture filtrate of Flavobacterium dormitator var. glucanolyticae. The molecular weight of the enzyme was estimated to be 17,000 ~ 22,000. The mode of enzyme action has been suggested to be a “random” type of β-1, 3-glucanase. The enzyme preferes larger chains saccharides as substrate for its action, however, smaller oligosaccharides such as laminaritriose and laminaribiose are also decomposed by the enzyme. The Km values of the enzyme for laminarin, laminarihexaose, and laminaritetraose were determined to be 0.26, 1.18, and 2.00 g/liter, respectively. The ability of this enzyme to disrupt the cells of living yeast is its remarkable point, since endo β-1, 3-glucanase of a smaller oligosaccharide-producing type from most sources has been recognized to be inactive (or very weakly active) on living yeast cells.  相似文献   
109.
Xylem parenchyma cells (XPCs) of boreal hardwood species adapt to sub-freezing temperatures by deep supercooling to maintain a liquid state of intracellular water near −40 °C. Our previous study found that crude xylem extracts from such tree species exhibited anti-ice nucleation activity to promote supercooling of water. In the present study, thus, we attempted to identify the causative substances of supercooling. Crude xylem extracts from katsura tree ( Cercidiphyllum japonicum ), of which XPCs exhibited deep supercooling to −40 °C, were prepared by methanol extraction. The crude extracts were purified by liquid–liquid extraction and then by silica gel column chromatography. Although all the fractions obtained after each purification step exhibited some levels of anti-ice nucleation activity, only the most active fraction was retained to proceed to the subsequent level of purification. High-performance liquid chromatography (HPLC) analysis of a fraction with the highest level of activity revealed four peaks with high levels of anti-ice nucleation activity in the range of 2.8–9.0 °C. Ultraviolet (UV), mass and nuclear magnetic resonance (NMR) spectra revealed that these four peaks corresponded to quercetin-3- O - β -glucoside (Q3G), kaempferol-7- O - β -glucoside (K7G), 8-methoxykaempferol-3- O - β -glucoside (8MK3G) and kaempferol-3- O - β -glucoside (K3G). Microscopic observations confirmed the presence of flavonoids in cytoplasms of XPCs. These results suggest that diverse kinds of anti-ice nucleation substances, including flavonol glycosides, may have important roles in deep supercooling of XPCs.  相似文献   
110.
The synthesis and SAR studies of 3- and 4-substituted 7-hydroxycoumarins as novel 17β-HSD3 inhibitors are discussed. The most potent compounds from this series exhibited low nanomolar inhibitory activity with acceptable selectivity versus other 17β-HSD isoenzymes and nuclear receptors.  相似文献   
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