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51.
Kyotaro Noguchi Tadashi Sakata Takeo Mizoguchi Masamichi Takahashi 《Journal of Forest Research》2005,10(6):435-441
Fine roots are a key component of forested ecosystems, but available information is still limited. This study examined the
production and mortality of fine roots less than 1 mm in diameter in a Japanese cedar (Cryptomeria japonica D. Don) plantation located on the Kanto Plain in central Japan. We used a minirhizotron technique in combination with soil
coring, and collected data for 1 year (May 2002–May 2003). Fine root production and mortality were determined from changes
in the lengths of individual fine roots on minirhizotron tubes. Both fine root production and mortality rates were greater
in the upper soil than in lower soil levels. Both rates were seasonal, with higher values in summer than in winter; this trend
was more pronounced in upper soil levels. These results suggest that environmental conditions, such as temperature or soil
properties, affect the production and mortality rates of fine roots. Fine root production and mortality occurred simultaneously,
and their rates were similar, which may have led to unclear seasonal changes in fine root standing crop estimates. Soil coring
indicated that the fine root biomass of this stand was about 120 g m−2, of which 40% was from Japanese cedar. The estimated rates of dry matter production and mortality of total fine roots, including
understory plants, were both approximately 300 g m−2 year−1. 相似文献
52.
Vitamin D Status in Different Stages of Disease Severity in Dogs with Chronic Valvular Heart Disease 下载免费PDF全文
T. Osuga K. Nakamura T. Morita S.Y. Lim K. Nisa N. Yokoyama N. Sasaki K. Morishita H. Ohta M. Takiguchi 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(6):1518-1523
Background
In humans with heart disease, vitamin D deficiency is associated with disease progression and a poor prognosis. A recent study showed that serum 25‐hydroxyvitamin D [25(OH)D] concentration, the hallmark of vitamin D status, was lower in dogs with heart failure than in normal dogs, and a low concentration was associated with poor outcome in dogs with heart failure.Objectives
To elucidate the vitamin D status of dogs with chronic valvular heart disease (CVHD) at different stages of disease severity.Animals
Forty‐three client‐owned dogs with CVHD.Methods
In this cross‐sectional study, dogs were divided into 3 groups (14 dogs in Stage B1, 17 dogs in Stage B2, and 12 dogs in Stage C/D) according to ACVIM guidelines. Dogs underwent clinical examination including echocardiography. Serum 25(OH)D concentrations were measured in each dog.Results
Serum 25(OH)D concentration was significantly lower in Stage B2 (median, 33.2 nmol/L; range, 4.9–171.7 nmol/L) and C/D (13.1 nmol/L; 4.9–58.1 nmol/L) than in Stage B1 (52.5 nmol/L; 33.5–178.0 nmol/L) and was not significantly different between Stage B2 and Stage C/D. Among clinical variables, there were significant negative correlations between 25(OH)D concentration and both left atrial‐to‐aortic root ratio and left ventricular end‐diastolic diameter normalized for body weight.Conclusions and Clinical Importance
These results indicate that vitamin D status is associated with the degree of cardiac remodeling, and the serum 25(OH)D concentration begins to decrease before the onset of heart failure in dogs with CVHD. 相似文献53.
Kimiko HONSHO Michiko HIROSE Masanori HATORI Lubna YASMIN Haruna IZU Shogo MATOBA Sumie TOGAYACHI Hiroyuki MIYOSHI Tadashi SANKAI Atsuo OGURA Arata HONDA 《The Journal of reproduction and development》2015,61(1):13-19
Quality evaluation of pluripotent stem cells using appropriate animal models needs to be improved for human regenerative medicine. Previously, we demonstrated that although the in vitro neural differentiating capacity of rabbit induced pluripotent stem cells (iPSCs) can be mitigated by improving their baseline level of pluripotency, i.e., by converting them into the so-called “naïve-like” state, the effect after such conversion of rabbit embryonic stem cells (ESCs) remains to be elucidated. Here we found that naïve-like conversion enhanced the differences in innate in vitro differentiation capacity between ESCs and iPSCs. Naïve-like rabbit ESCs exhibited several features indicating pluripotency, including the capacity for teratoma formation. They differentiated into mature oligodendrocytes much more effectively (3.3–7.2 times) than naïve-like iPSCs. This suggests an inherent variation in differentiation potential in
vitro among PSC lines. When naïve-like ESCs were injected into preimplantation rabbit embryos, although they contributed efficiently to forming the inner cell mass of blastocysts, no chimeric pups were obtained. Thus, in vitro neural differentiation following naïve-like conversion is a promising option for determining the quality of PSCs without the need to demonstrate chimeric contribution. These results provide an opportunity to evaluate which pluripotent stem cells or treatments are best suited for therapeutic use. 相似文献
54.
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment in an aerobic bioreactor packed with carbon fibers 下载免费PDF全文
Takahiro Yamashita Ryoko Yamamoto‐Ikemoto Hiroshi Yokoyama Hirofumi Kawahara Akifumi Ogino Takashi Osada 《Animal Science Journal》2015,86(3):358-368
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N2O emission and avoiding NOx (NO3 + NO2) accumulation. The N2O emission factor was 0.0003 g N2O‐N/gTN‐load in the CF bioreactor compared to 0.03 gN2O‐N/gTN‐load in an activated sludge reactor (AS reactor). N2O and CH4 emissions from the CF reactor were 42 g‐CO2 eq/m3/day, while those from the AS reactor were 725 g‐CO2 eq/m3/day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH4‐N, and accumulated an average of 14 mg/L of the NO3‐N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH4‐N and accumulated an average 183 mg/L of the NO3‐N. NO2‐N was almost undetectable in both reactors. 相似文献
55.
Takaya Y Furukawa T Miura S Akutagawa T Hotta Y Ishikawa N Niwa M 《Journal of agricultural and food chemistry》2007,55(1):75-79
Constituents in a distillation residue of Awamori (millet spirits) and their antioxidant activity are investigated in this study. The supernatant of the distillation residue obtained by centrifugation was partitioned with n-hexane, chloroform, ethyl acetate, and n-butanol against water to afford the corresponding solubles. Among them, n-hexane and chloroform solubles showed higher antioxidant potency than l-ascorbic acid by the bleomycin-Fe method. In chloroform solubles, seven cyclic dipeptides were identified along with ethyl 2-pyrrolidione-5-carboxylate, tyrosol, and ethyl p-hydoroxyphenyllactate. Antioxidant activity of ethyl p-hydoroxyphenyllactate was 4.2 times that of l-ascorbic acid, whereas cyclic dipeptides showed activity 0.89-1.29 times as strong as that of l-ascorbic acid. On the other hand, scavenging effect of cyclic dipeptides against O(2)(-.) and OH(.) by using electron spin resonance was also investigated. In the results, cyclo(l-Ile-l-Pro) showed significantly strong inhibitory effect against OH(.) (95.4% at 2.5 x 10-3 M) and cyclo(l-Phe-l-Pro), cyclo(l-Pro-l-Val), and cyclo(l-Leu-l-Pro) inhibited OH(.) 64.9, 54.1, and 51.0%, respectively, whereas alpha-tocopherol showed 37.7% inhibition, though only a few cyclic dipeptides weakly inhibited O(2)(-.). 相似文献
56.
Yokoyama T Matsumoto Y Meshitsuka G 《Journal of agricultural and food chemistry》2007,55(4):1301-1307
Several phenolic compounds were subjected to oxygen-alkali oxidations under oxygen delignification conditions, and their degradations were examined in detail by applying a novel formula. The formula was established on the basis of the two following considerations. The degradation of the phenolic compounds should be expressed by the sum of two types, each of which is caused by molecular oxygen and by highly reactive active oxygen species (HAOS). The degradation should be described by a mathematical equation to which a rate function, k(t), dependent on reaction time t, is applied instead of a rate constant. By rearrangements, the following formula was obtained: k(t) = A/(t + B) (A, B are constants). This is hyperbola, and the illustration of k(t) visualized the contribution of HAOS to the degradation of the phenolic compounds. HAOS did not contribute so much to the degradation, especially at 70 degrees C, which suggests the low energy supply for the HAOS generation at 70 degrees C. The extrapolation of k(t) to the beginning of the reaction gives its initial value, k(initial), which is the rate constant of the reaction between the phenolic compounds and molecular oxygen. As expected, k(initial) was dependent on the electronic property of their substituents. Quantification of the phenolic compounds degraded by HAOS showed that the contribution of HAOS to the degradation is not great. The maximum contribution was observed in the oxidation of 2,6-dimethylphenol at 85 degrees C. In this case, 5 and 95% of the compound were degraded by HAOS and molecular oxygen, respectively. 相似文献
57.
K. Nakamura T. Osuga K. Morishita S. Suzuki T. Morita N. Yokoyama H. Ohta M. Yamasaki M. Takiguchi 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(6):1746-1752
Background
A strong correlation between left atrial (LA) dysfunction and the severity of cardiac disease has been described in human patients with various cardiac diseases. The role of LA dysfunction in dogs with chronic mitral valvular heart disease (CMVHD) has not been addressed.Objectives
To investigate the correlation between LA function and the prognosis of dogs with CMVHD.Animals
Thirty‐eight client‐owned dogs with CMVHD.Methods
Prospective clinical cohort study. Dogs were divided into 2 groups (survivors and nonsurvivors) based on the onset of cardiac‐related death within 1 year. Physical examination and echocardiographic variables were compared between the groups. For the assessment of the comparative accuracy in identifying patients with cardiac‐related death, receiver operating characteristic (ROC) curves and multivariate logistic analysis were used.Results
The highest accuracy was obtained for the LA active fractional area change (LA‐FAC act), with an area under the ROC curve (AUC) of 0.95, followed by the left atrial to aortic root ratio (LA/Ao), with an AUC of 0.94; peak early diastolic mitral inflow velocity (E), with an AUC of 0.85; and LA total fractional area change (LA‐FAC total), with an AUC of 0.85. In the multivariate logistic regression analysis, LA‐FAC act emerged as the only independent correlate of cardiac‐related death within 1 year (odds ratio = 1.401, P = .002).Conclusions and Clinical Importance
Regarding both the size and function, the LA has a strong correlation with the prognosis of dogs with CMVHD. The most significant independent predictor of mortality in this study was LA‐FAC act. 相似文献58.
Henneguya pagri n. sp. (Myxozoa: Myxosporea) is described from netpen-cultured red sea bream, Pagrus major, in Japan. Affected fish displayed anaemic gills, an enlarged bulbus arteriosus and internal haemorrhaging in the pericardial cavity. Disease outbreaks occurred during the summer and the prevalence of infection reached 75% in August. Plasmodia of H. pagri developed in the bulbus arteriosus of red sea bream, in which degenerative cardiomyopathy was observed. Following maturation of the parasite, the influx of spores into the gills caused congestion of the gill capillaries, resulting in proliferative branchitis. Spores (10.5 x 7.5 microm) were ovoid with two caudal appendages (29.6 microm in average length), with a whip-like extension from the end. Partial small subunit ribosomal RNA gene sequences of H. pagri are closely related to those of H. lateolabracis infecting the bulbus arteriosus of Chinese sea bass, Lateolabrax sp. 相似文献
59.
60.
Shoshi Mizuta Yuko Nakanishi Masashi Shiraishi Yoshihiro Yokoyama Reiji Yoshinaka 《Fisheries Science》2007,73(6):1353-1361
ABSTRACT: To obtain fundamental information for the effective use of scallop Patinopecten yessoensis mantle, which is one of the underutilized marine resources. Some properties of collagen contained in the mantle were examined by chemical and histochemical techniques. Collagen content in the mantle varied annually, ranging from 0.98 to 1.72% of wet tissue, 7.7 to 12.6% of dry tissue and 13.5 to 26.5% of total protein, being relatively in high level of collagen content of invertebrate muscles. Collagen fiber was densely distributed in the inner connective tissue matrix of the mantle pallial, in contrast to the inner fold part which was rich in muscle fibers. The collagen contained in the crude collagen fraction (residue after alkali extraction), prepared from the mantle, was revealed to have considerably low solubility on hot-water extraction, constantly less than 20% of the total collagen at the temperatures in the range of 20–90°C. 相似文献