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41.
42.
The antiangiogenic effects of fucoxanthin and a deacetylated product, fucoxanthinol, were examined. Fucoxanthin significantly suppressed HUVEC proliferation and tube formation at more than 10 microM, but it had no significant effect on HUVEC chemotaxis. The formation of blood vessel-like structures from CD31-positive cells was evaluated using embryonic stem cell-derived embryoid bodies. Fucoxanthin effectively suppressed the development of these structures at 10-20 microM, suggesting that it could suppress differentiation of endothelial progenitor cells into endothelial cells involving new blood vessel formation. Fucoxanthin and fucoxanthinol suppressed microvessel outgrowth in an ex vivo angiogenesis assay using a rat aortic ring, in a dose-dependent manner. These results imply that fucoxanthin having antiangiogenic activity might be useful in preventing angiogenesis-related diseases.  相似文献   
43.
Two detection methods combining loop-mediated isothermal amplification (LAMP) and a bait trap were developed to detect Pythium helicoides in greenhouses containing roses, miniature roses, and poinsettias in hydroponic culture systems. In “Bait-LAMP”, a crude extract derived from perilla seeds as the bait was used in the LAMP reaction, whereas in the “Bait culture-LAMP”, a crude extract of mycelia grown out from perilla seeds onto Pythium-selective medium served as the bait. The two methods are simple and rapid for practical monitoring of P. helicoides in hydroponic culture systems.  相似文献   
44.
Degradation of chitin, which is an aminopolysaccharide used as a soil amendment, has been often monitored in soil via its degradation products such as carbon dioxide and ammonium. We report here the applicability of thermogravimetry to measure the amount of chitin added to soil. The maximum pyrolysis rate of the upland surface soil of Brown Forest soil supplemented with chitin was strongly correlated with added chitin content (r = 0.999) when the content exceeded 6.0 g kg?1. The maximum pyrolysis rates of chitin-added soil (around 385°C) was distinctive from those of soil supplemented with cellulose, chitosan, N-acetylglucosamine, and N,N’-diacetylchitobiose (around 340°C, 300°C, 200°C, and 240°C, respectively), indicating the specific detection of chitin. Soil incubation study demonstrated that 60 g kg?1 chitin added to the soil declined exponentially (r = 0.993) within days and could not be detected at 90 days after the addition of chitin. Total carbon (C) content also decreased within days whereas total nitrogen (N) remained almost constant over the 90 days. The amount of ammonium-N increased in the initial 30 days after the addition of chitin and reached about 3.6 g kg?1, which corresponded to the amount of N in the added chitin (4.1 g kg?1) while the amount of nitrite-N and nitrate-N were below 2.0 and 15 mg kg?1, respectively. Comparison of the measured ammonium-N and total-C contents with those calculated from the measured chitin-content implied that addition of chitin enhanced degradation of native organic compounds in soil.  相似文献   
45.
We investigated the feasibility of cryopreservation of spermatogonia and oogonia in the critically endangered cyprinid honmoroko Gnathopogon caerulescens using slow-cooling (freezing) and rapid-cooling (vitrification) methods. Initially, we examined the testicular cell toxicities and glass-forming properties of the five cryoprotectants: ethylene glycol (EG), glycerol (GC), dimethyl sulfoxide (DMSO), propylene glycol (PG), and 1,3-butylene glycol (BG), and we determined cryoprotectant concentrations that are suitable for freezing and vitrification solutions, respectively. Subsequently, we prepared the freezing solutions of EG, GC, DMSO, PG, and BG at 3, 2, 3, 2, and 2 M and vitrification solutions at 7, 6, 5, 5, and 4 M, respectively. Following the cryopreservation of the testicular cells mainly containing early-stage spermatogenic cells (e.g., spermatogonia and primary spermatocytes), cells were cultured for 7 days and immunochemically stained against germ cell marker protein Vasa. Areas occupied by Vasa-positive cells indicated that vitrification led to better survival of germ cells than the freezing method, and the best result was obtained with 5 M PG, about 50% recovery of germ cells following vitrification. In the case of ovarian cells containing oogonia and stage I, II, and IIIa oocytes, vitrification with 5 M DMSO resulted the best survival of oogonia, with equivalent cell numbers to those cultured without vitrification. The present data suggest that male and female gonial cells of the endangered species G. caerulescens can be efficiently cryopreserved using suitable cryoprotectants for spermatogonia and oogonia, respectively.  相似文献   
46.
The disinfection effect of slightly acidic electrolyzed water (SAEW) use in a farm where Pseudomonas mastitis has spread was evaluated. Despite the application of antibiotic therapy and complete cessation of milking infected quarters, numerous new and recurrent Pseudomonas aeruginosa clinical mastitis infections (5.8–7.1% of clinical mastitis cases) occurred on the farm from 2003 to 2005. Procedural changes and equipment modifications did not improve environmental contamination or the incidence of Pseudomonas mastitis. To more thoroughly decontaminate the milking parlor, an SAEW system was installed in 2006. All milking equipment and the parlor environment were sterilized with SAEW (pH 5–6.5, available chlorine 12 parts per million) before and during milking time. After adopting the SAEW system, the incidence of clinical and subclinical Pseudomonas mastitis cases decreased significantly (< 0.0001) and disappeared. These findings suggest that SAEW effectively reduced the incidence of mastitis in a herd contaminated by Pseudomonas species. This is the first report to demonstrate the effectiveness of disinfection by SAEW against mastitis pathogens in the environment.  相似文献   
47.
Toll-like receptor 4 (TLR4) and myeloid differentiation factor 2 (MD-2) are essential for recognizing the lipopolysaccharides (LPS) of Gram-negative bacteria. We determined the sequences of cDNAs encoding TLR4 and MD-2 from cetaceans and generated three-dimensional (3D) models for a better understanding of their modes of interaction and LPS recognition. The 3D reconstructions showed that cetacean TLR4 and MD-2 formed a horseshoe-like structure comprised of parallel β-strands and a β-cup structure consisting of two anti-parallel β-sheets, respectively. The (TLR4-MD-2)2 duplex-heterodimer was shown to form a symmetrical structure. Comparison with the interfaces of the complexes in other mammals revealed that cetacean TLR4s have some amino acid residue substitutions involved in duplex-heterodimer formation and in species variation for LPS recognition. These substitutions in the changed amino acid residues may alter the interaction among TLR4, MD-2, and LPS and modify the TLR4/MD-2 immunological responses.  相似文献   
48.
Quantitative PCR revealed that Tomato chlorotic dwarf viroid (TCDVd) was present in substantial amounts in viroid-infected tomato flowers. Healthy tomato plants were arranged in two different glasshouses, and plants were mechanically inoculated with TCDVd. Bumblebees (Bombus ignitus) were then introduced into the glasshouses to reveal whether the viroid was transmitted from infected source plants to neighbouring healthy plants. TCDVd infection was found in neighbouring tomato plants more than 1 month after the introduction of the bees, some of which expressed symptoms, in both glasshouses. Thus, bumblebees transmitted TCDVd from tomato to tomato by pollination activities.  相似文献   
49.
Fisheries Science - Gene expression profiles during the transition from fasting to refeeding were investigated in the gut and liver of Masu salmon Oncorhynchus masou masou. Fish were starved for...  相似文献   
50.
Changes in the diet have been previously reported to alter the gut bacterial profile in several organisms, including shrimp. These shifts in microbial structure either promote beneficial effects to the host or cause diseases. Supplementation of 5‐aminolevulinic acid (5‐ALA), the precursor of tetrapyrroles, has been previously reported to enhance shrimp's immune response. To know whether 5‐ALA has effects on the gut bacterial structure in Pacific white shrimp (Litopenaeus vannamei), we investigated the bacterial communities in the intestine and stomach of L. vannamei using high‐throughput Illumina sequencing of 16S rRNA gene libraries. One week of 5‐ALA supplementation altered the bacterial community structure (beta diversity) in both tissues, as shown by the results of multi‐dimensional scaling (MDS) plots and analysis of similarities (ANOSIM). DESeq2 analysis revealed enrichment of differentially abundant taxa in the 5‐ALA group (e.g. Enhydrobacter and Oceaniovalibus) and control group (e.g. Tenacibaculum and Mycobacterium). Metagenomic predictions suggested that the control group had more KEGG pathways associated with ‘metabolism’ than the 5‐ALA group. This study suggests that 5‐ALA supplementation potentially promotes the formation of a beneficial bacterial community structure in shrimp. This is the first report on the effect of 5‐ALA supplementation on the bacterial community profile in any organism.  相似文献   
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