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1.
A comparison of changes in stable isotope ratios in the epidermal mucus and muscle tissue of slow‐growing adult catfish 下载免费PDF全文
Atsushi Maruyama Emi Tanahashi Takanobu Hirayama Ryuji Yonekura 《Ecology of Freshwater Fish》2017,26(4):636-642
Although stable isotope analysis is a powerful tool for determining diet, migration patterns and the structure of food webs in aquatic systems, the slow response of isotopic ratios in the widely used muscle tissue often hampers this approach, particularly in slow‐growing or adult fishes. We conducted a diet‐switch experiment to compare the changes in the stable carbon isotope ratio (δ13C values) in the epidermal mucus and muscle tissue of five‐year‐old catfish (Silurus asotus). The isotope ratios in noninvasively sampled mucus changed more rapidly than those in the muscle tissue. As isotopic change in mucus was relatively rapid, this technique can be used over a finer timescale than traditional isotopic analyses using the muscle tissue. The isotopic change half‐life in our experimental condition was 200 days, which would not be short enough for some research purposes. Examining mucus along with the muscle would enable food habits of slow‐growing fishes to be determined over different timescales. However, the rate of isotopic change in the mucus was negatively affected by the size of fish and was slower than the previously reported rates in juvenile steelhead. These findings suggest that mucus turnover rates need to be determined prior to the field data interpretation. 相似文献
2.
Charlotte M. Keenan Julia F. Baker Alys E. Bradley Dawn G. Goodman Takanori Harada Ronald Herbert Wolfgang Kaufmann Rupert Kellner Beth Mahler Emily Meseck Thomas Nolte Susanne Rittinghausen John Vahle Katsuhiko Yoshizawa 《Journal of toxicologic pathology》2015,28(1):51-53
The INHAND Proposal (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) has been operational since 2005. A Global Editorial Steering Committee (GESC) manages the overall objectives of the project and the development of harmonized terminology for each organ system is the responsibility of the Organ Working Groups (OWG), drawing upon experts from North America, Europe and Japan.Great progress has been made with 9 systems published to date – Respiratory, Hepatobiliary, Urinary, Central/Peripheral Nervous Systems, Male Reproductive and Mammary, Zymbals, Clitoral and Preputial Glands in Toxicologic Pathology and the Integument and Soft Tissue and Female Reproductive System in the Journal of Toxicologic Pathology as supplements and on a web site – www.goreni.org. INHAND nomenclature guides offer diagnostic criteria and guidelines for recording lesions observed in rodent toxicity and carcinogenicity studies. The guides provide representative photo-micrographs of morphologic changes, information regarding pathogenesis, and key references. During 2012, INHAND GESC representatives attended meetings with representatives of the FDA Center for Drug Evaluation and Research (CDER), Clinical Data Interchange Standards Consortium (CDISC), and the National Cancer Institute (NCI) Enterprise Vocabulary Services (EVS) to begin incorporation of INHAND terminology as preferred terminology for SEND (Standard for Exchange of Nonclinical Data) submissions to the FDA. The interest in utilizing the INHAND nomenclature, based on input from industry and government toxicologists as well as information technology specialists, suggests that there will be wide acceptance of this nomenclature. The purpose of this publication is to provide an update on the progress of INHAND. 相似文献
3.
Kazuhiko ARAHARA Takashi MATSUMOTO Fumiki MORIMATSU Katsuhiko ARAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1503-1506
In this study, the effect of fibronectin on the neurite outgrowth from embryoid
bodies (EBs) in neurodifferentiated embryonal carcinoma P19 cells was examined. The
neurite outgrowth on fibronectin was maintained for a longer time in comparison with those
on collagen or laminin. Quantitative RT-PCR revealed that mRNA level corresponding to
sonic hedgehog (Shh) in neurodifferentiated P19 cells was upregulated on fibronectin,
whereas collagen or laminin did not affect. Further knockdown of integrin αv subunit in
P19 cells demonstrated that expression of Shh was mediated through interaction between
fibronectin and integrin. Additionally, exogenous Shh agonist accelerated neurite
outgrowth from embryonic stem cell-derived EBs without large change of neuronal phenotype
expression. Taken together, fibronectin could maintain neurite outgrowth via increased Shh
expression. 相似文献
4.
We studied the effect of genotypes of planting stocks regarding the variation of the modulus of elasticity of tree trunks on standing trees (trunk-MOE), tree height (TH), and diameter at breast height (DBH) in a 19-year-old Japanese cedar plantation made with root cuttings. Trunk-MOE was assessed nondestructively using a tree-bending method. Genotypes of individual trees were detected using the random amplified polymorphic DNA (RAPD) technique. RAPD analysis revealed that the sampled plantation consisted of 14 genotypes. Genotypic effects on DBH and TH were unclear, and there was no significant difference among genotypes. This result indicated that an acquired variation should have more influence than an inherited variation on DBH and TH. For trunk-MOE, there were significant differences among the four largest genotypes at the 5% level. However the coefficient of variation in trunk-MOE of each genotype ranged from 7.5% to 26.8%. It seems reasonable to assume that the wide variation in trunk-MOE in a sampled plantation may depend on the environmental effect within a clone as well as on the genetic origin of clones. We therefore conclude that the use of multiple planting stocks from different cuttings for which the wood quality is unknown contributed strongly to the wide variation in trunk-MOE in the plantation of Japanese cedar. 相似文献
5.
Somatic embryogenesis in Chamaecyparis pisifera Sieb. et Zucc. was initiated from immature seeds collected from the end of June to early July. Mass propagation through adventitious
shoot bud production from somatic embryo culture on Woody Plant (WP) medium and artificial seed production using sodium alginate
was achieved. A high bud forming index value (25.8) was obtained on medium supplemented with 1 μM 6-benzylaminopurine. The conversion rates from artificial seeds under aseptic and nonaseptic conditions were 60%–100% and
10%–12%, respectively. For germplasm conservation, somatic embryos and embryogenic cells were successfully stored at 4°C (medium-term
storage) and in liquid nitrogen for long-term storage.
Received: December 21, 2001 / Accepted: August 1, 2002
Acknowledgments This work was supported in part by the Japan Science and Technology Corporation and in part by a Grant for Research for the
Future Program from the Japan Society for the Promotion of Science.
Correspondence to:E. Maruyama 相似文献
6.
F.?Ishiguri S.?Maruyama K.?Takahashi Z.?Abe S.?Yokota M.?Andoh N.?YoshizawaEmail author 《Journal of Wood Science》2003,49(2):135-139
Sugi green logs with red or black heartwood were smoke-heated, and the changes in the color of the heartwood after ultraviolet
(UV) (λ = 365 nm) radiation exposure were then observed. After UV radiation exposure, the redness and yellowness increased in both
the red and black heartwoods, whereas the brightness decreased. In the black heartwood, the resulting color turned from yellowish
white to reddish brown. Reddening in black heartwood after exposure to a combination of smoke heating and UV radiation is
thought to be due to a decrease in brightness and an increase in both redness and yellowness. However, the degree of change
in heartwood color by UV radiation exposure was not greatly affected by smoke-heating treatments of various lengths. When
methanol extracts were fractionated and exposed to UV radiation, the yellowness increased in the n-hexane-soluble portion and the redness increased in the acetone-soluble fractions from the n-hexane-insoluble portion. These results suggest that the n-hexane-soluble fraction contains the substances that allow heartwood color to change to yellow after UV radiation exposure,
and the acetone-soluble-fraction from the n-hexane-insoluble portion contains the substances that allow it to change to red.
Received: November 14, 2001 / Accepted: June 3, 2002
Acknowledgment This research was supported in part by a Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of
Science.
This study was presented in part at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001
Correspondence to:N. Yoshizawa 相似文献
7.
8.
Hitoshi Fujiie Atsushi Maruyama Masako Fujiie Michiko Takagaki Douglas J. Merrey Masao Kikuchi 《Irrigation and Drainage Systems》2011,25(1):39-60
It is well-known that major irrigation projects have a strong scale economy, handicapping irrigation development in sub-Saharan
Africa (SSA) because of the difficulty in formulating large-scale projects. Using project-level investment cost and performance
data of major and minor irrigation projects, this paper examines the causes of the economy of scale phenomenon. We find that
strong scale economy exists not only for major but also for minor projects, i.e., small- and micro-scale, projects. This is
largely because of the existence of indivisible overhead costs such as high-opportunity-cost human resources for planning,
designing and engineering management and supervision. We also find that large differences between major and minor projects
in the absolute level of overhead as well as construction costs creates a strong scale diseconomy and results in better performance
of minor projects. The advantage of minor projects holds even when their higher risk associated with the water source is taken
into consideration. We argue that there is an urgent need to promote irrigation development in SSA through developing minor
projects, and to reduce the heavy burden of overhead costs by developing the capacity of human resources at the national,
local and farmer levels in the fields of irrigation engineering, irrigation agronomy, institutional development, and micro
water management technologies. 相似文献
9.
Sekimata K Han SY Yoneyama K Takeuchi Y Yoshida S Asami T 《Journal of agricultural and food chemistry》2002,50(12):3486-3490
Screening for brassinosteroid biosynthesis inhibitors was performed to find azole derivatives that induced dwarfism, to resemble brassinosteroid-deficient mutants in Arabidopsis, and which could be rescued by brassinosteroid. Through this screening experiment, propiconazole fungicide was selected as a likely inhibitor of brassinosteroid biosynthesis and, thus, propiconazole derivatives with optimized activity and selectivity were synthesized. The biological activity of these compounds was evaluated by examining cress stem elongation. Among the compounds tested, 2RS,4RS-1-[2-(4-trifluoromethylphenyl)-4-n-propyl-1,3-dioxolan-2-ylmethyl]-1H-1,2,4-triazole (12) showed the most potent capability to retard cress stem elongation in the light. The compound-induced hypocotyl dwarfism was restored by the coapplication of 10 nM brassinolide but not by 1 microM gibberellin. These results suggest that 12 should affect brassinosteroid biosynthesis. The potency and specificity of 12 were greater than those of brassinazole, a previously reported brassinosteroid biosynthesis inhibitor. 相似文献
10.
Tandang MR Adachi M Inui N Maruyama N Utsumi S 《Journal of agricultural and food chemistry》2004,52(22):6810-6817
The primary structure of Brassica napus procruciferin 2/3a was engineered to elucidate structure-function relationships and to improve the functionality of cruciferin. The following mutants were constructed: (1) C287T, (2) DeltaII, variable region II was deleted; (3) C287T/DeltaII, mutation involving (1) and (2); (4) DeltaIV + A1aIV; and (5) DeltaIV + A3IV, variable region IV was replaced with variable region IV containing many charged residues from soybean glycinin A1aB1b and A3B4 subunits. Differential scanning calorimetry analysis revealed that the A1aIV region has a more favorable interaction with the procruciferin molecule than does A3IV as well as the original regions. On the basis of heat-induced precipitation analysis, it was concluded that replacement of the free cysteine residue with threonine (C287T) and insertion of charged regions (DeltaIV + A1aIV and DeltaIV + A3IV) could lead procruciferin to form soluble aggregates after heating. Low solubility was observed in mutants DeltaIV + A3IV, DeltaII, and C287T/DeltaII, especially between pH 4 and 6 at mu = 0.08, but not in DeltaIV + A1aIV, indicating that the number of acidic amino acid residues and the high number of glutamine residues are important factors for solubility at mu = 0.08. None of the mutants showed any improvements in emulsifying ability, indicating that destabilization and addition of the hydrophilic region are not effective for emulsification. The insertion of the A1aIV region in procruciferin made the molecule more susceptible to alpha-chymotrypsin. 相似文献