Corynespora leaf spot of scarlet sage caused by <Emphasis Type="Italic">Corynespora cassiicola</Emphasis>

A leaf spot disease of scarlet sage (Salvia splendens Sellow ex J.A. Shultes) found in Kanagawa and Tokyo prefectures was demonstrated to be caused by Corynespora cassiicola (Berk. and Curt.) Wei based on inoculation experiments, and morphological identification of the pathogenic fungus. Isolates of C. cassiicola from cucumber, green pepper, and hydrangea were also pathogenic to scarlet sage leaves. Although the isolates from cucumber, green pepper, and hydrangea were pathogenic to scarlet sage leaves, the scarlet sage isolate was not pathogenic to cucumber, green pepper, hydrangea, eggplant, tomato or soybean.     

章古台地区樟子松年轮宽度和管胞长度的径向变异

对章古台地区不同密度樟子人工林松年轮宽度和管胞长度进行测定,结果表明：章古台地区胸径年轮数30a的樟子松林,已出现生长衰退现象,生长衰退期开始林龄与林分密度有关,降低林分密度可延缓衰退期出现林龄。樟子松管胞长度与距离髓心的年轮数之间存在Y=alnx＋b（Y：管胞长度;X：距离髓心的年轮数．b：第1年轮的管胞长度）关系。不同密度樟子松年轮宽度不同,但管胞长度与未成熟材范围无显著变化,未成熟材范围距离髓心的年轮数均为21～23a。     

Supplementing transglucosidase with a high-fiber diet for prevention of postprandial hyperglycemia in streptozotocin-induced diabetic dogs

Indigestible oligosaccharides have been shown to normalize blood glucose and insulin concentration thereby promoting good health and preventing diseases, such as diabetes. Transglucosidase (TG, α-glucosidase, enzyme code (EC) 3.2.1.20) is an enzyme capable of converting starch to oligosaccharides, such as iso-malto-oligosaccharides from maltose, via the action of amylase. The aim of this study was to evaluate whether oral administration of TG with maltose or dextrin is capable of reducing post-prandial serum glucose concentration in experimentally streptozotocin (STZ)-induced diabetic dogs fed on a high-fiber diet. Five healthy and five STZ-induced diabetic dogs were employed in this study. TG supplementation with dextrin or maltose had no detrimental effect in healthy dogs. In fact, TG and dextrin exhibited a flatlined serum glucose pattern, while reducing mean post-prandial serum insulin and glucose concentration as compared to control diet alone. When TG supplementation was tested in STZ-induced diabetic dogs under the context of a high fiber diet, a 13.8% and 23.9% reduction in mean glucose concentration for TG with maltose and dextrin, respectively was observed. Moreover, TG with dextrin resulted in a 13% lower mean post-prandial glucose concentration than TG with maltose, suggesting that dextrin may be a more efficient substrate than maltose when used at the same concentration (1 g/kg). Our results indicate that TG supplementation with diet can lead to lower postprandial glucose levels versus diet alone. However, the efficacy of TG supplementation may depend on the type of diet it is supplemented with. As such, TG administration may be useful for preventing the progression of diabetes mellitus and in its management in dogs.     

Age, growth, and reproductive characteristics of dolphinfish Coryphaena hippurus in the waters off west Kyushu, northern East China Sea

The growth and reproductive characteristics of dolphinfish Coryphaena hippurus collected in the waters off western Kyushu from May 2008 to April 2011 were determined based on scale and otolith readings and gonad histological examinations, respectively. Based on annual increments in scales and daily increments in sagittal otoliths, the von Bertalanffy growth curves in male and females were determined as $ FL_{t} = 1049[1 - \exp \{ - 0.835(t + 6.975 \times 10^{ - 14} )\} ] $ and $ FL_{t} = 938[1 - \exp \{ - 1.029(t + 6.975 \times 10^{ - 14} )\} ] $ , respectively, where FL _t is the mean fork length (mm) at age t. The spawning period was found to last from June to August for dolphinfish, based on an examination of the monthly changes in the gonadosomatic index and histological observations. Therefore, based on the relationship between the fork length and the developmental stage of the testes or ovaries, male and female dolphinfish were found to reach sexual maturity by the following spawning season after hatching in the northern East China Sea.     

Highly efficient induction of triploid Pacific abalone <Emphasis Type="Italic">Haliotis discus hannai</Emphasis> by caffeine treatment

ABSTRACT:   In order to develop a highly efficient method for mass production of triploid Pacific abalone Haliotis discus hannai , caffeine treatment that is safe and inexpensive was optimized. To suppress the first meiotic division, fertilized eggs were exposed to either a 10- or 15-mM caffeine solution for 24 min beginning at 12 min after fertilization. In most treated batches, the rates of cleaved eggs showed no significant difference from the control batches. However, in most treated batches, the rates of occurrence of normal larvae and the survival rates of the early juveniles were significantly lower than those of the controls. The triploid rates at 6 days to 11 months after settlement in all the treated batches were extremely high (91–100%). There was no significant difference in the mean triploid rates between 10- and 15-mM caffeine treatments. These results suggest that both treatment conditions were conducive to triploid abalone production. One live 2n/3n mosaic specimen was found in the treated batches. However, since the frequency of mosaic was extremely low, the mosaicism would probably not have an adverse effect on the stable production of triploid abalones.     

Formation process of staining-type hypermelanosis in Japanese flounder juveniles revealed by examination of chromatophores and scales

Staining-type hypermelanosis, defined as blind-side melanosis occurring after completion of metamorphosis, reduces commercial value in hatchery-produced flatfishes. Detailed characterization was performed on the stained area of juvenile Japanese flounder Paralichthys olivaceus to physiologically understand this phenomenon. From 80 to 120 days after hatching, juveniles were reared in sandy and sandless tanks. By classifying the staining degree into 7 levels, about 2 times higher occurrence of middle-level staining was reconfirmed in sandless tank (about 80 %) than in sandy tank (about 40 %). In the stained area, we found 3 types of chromatophores (melanophore, xanthophore, and iridophore) and ctenoid scales, which would be typically observed on the normal ocular side. Detailed examination on the melanophores revealed further similarity between the stained area and the normal ocular side, in terms of the distribution at 2 layers (shallower and deeper than scale), and the densities in both layers (about 1000 cells/mm² above scale and 200 cells/mm² beneath scale). These results strongly suggest that the staining is a status change in the body surface conditions from the blind side to that on the ocular side, and not a simple darkening caused by disordered proliferation of melanophores on the blind side.     

Self-feeding behavior of yellowtail, Seriola quinqueradiata, in net cages: diel and seasonal patterns and influences of environmental factors

The self-feeding pattern of yellowtail, Seriola quinqueradiata, maintained in floating net cages was examined throughout a year, and the influence of seasonal changes of the photoperiod and water temperature on the feeding pattern was investigated. Two groups of 50 yellowtail (initial mean body weight about 50 and 80 g, respectively) were kept in two experimental net cages (2×3×4 m deep), with a self-feeding device installed on each. It was possible to maintain yellowtail in net cages using a self-feeder throughout almost a year. The number of daily food demands was greatly affected by the seasonal changes in water temperature. Yellowtail showed high self-feeding activity, above 18 °C; depressing water temperatures did not influence the activity when the water temperature was over 18 °C. However, the activity decreased when the water temperature fell below 18 °C. The feeding pattern in a 24-h period was greatly affected by the temporal changes in light intensity. Annual observations revealed that yellowtail showed generally crepuscular plus nocturnal feeding behavior and had two peaks of feeding activity a day. These peaks appeared at dawn and dusk; moreover, a clear association between the most active time of self-feeding and the period of the greatest change in light intensity was observed. The results suggest that a change in light intensity might stimulate the appetite of yellowtail or that there is a light level at which yellowtail prefer to eat.     

Protective effects of thiol compounds on chromate-induced cytotoxicity in HeLa cells.

The effects of several thiol compounds on the cytotoxicity induced by chromate (potassium dichromate) were examined. HeLa cells were incubated in Eagle's minimum essential medium (MEM) with or without the chromate alone, or with both chromate and any one of L-cysteine ethyl ester (LCysEE), L-cysteine methyl ester (LCysME), N-acetyl-L-(+)-cysteine, 2,3-dimercaptosuccinic acid (DMSA), 2, 3-dimercapto-1-propanesulfonic acid (DMPS), or dithiothreitol. After a given period of incubation, the number of viable cells was counted using the trypan blue exclusion test and the chromium content of the cells was estimated by atomic absorption spectrophotometry. The results obtained were as follows. 1) Chromate-induced cytotoxicity evaluated by inhibition of cell growth at 3 days of incubation was diminished by all of the thiol compounds tested when the cells were incubated in MEM with 2.5 to 10.0 microM chromate and 25 to 100 microM thiol compounds. 2) All of the thiol compounds produced a concentration-dependent reduction of chromate when a solution of the thiol compound (12.5 to 100 microM) was mixed with a solution of chromate (10 microM) in distilled water. 3) When cells were incubated in MEM with both 10 microM chromate and 25 to 100 microM thiol compounds, the chromium content of the cells at 6 hr of incubation was decreased in a concentration-dependent manner. 4) When these thiol compounds were added to MEM 1 hr before or after chromate, no or little protective effects of these thiol compounds against chromate-induced cytotoxicity and chromium uptake by the cells were observed.(ABSTRACT TRUNCATED AT 250 WORDS)     

Induction of lipid peroxidation in mice by hexavalent chromium and its relation to the toxicity

Comparative effects of hexavalent (K2Cr2O7:Cr(VI)) and trivalent chromium (Cr(NO3)3:Cr(III)) on the development of lipid peroxidation, and the relationship between the lipid peroxidation and damage to tissues were studied using male ddY strain mice. The animals were administered with either of two chemicals at a dose of 20 mg Cr/kg by a single intraperitoneal injection. The results obtained were as follows: (1) Lipid peroxidation in the liver, as measured by the synthesis of thiobarbituric acid reactive substances (TBARS), showed a significant increase at 24 and 48 hr after Cr(VI) injection, while in the kidney it was observed only at 48 hr. In the mice administered with Cr(III), TBARS formation in the liver went down below the control levels, while no change was observed in the kidney. (2) Chromium contents in the liver and kidney showed a maximum level at 6 hr after injection of Cr(VI) and then those declined to the half of the maximum level at 48 hr, respectively. Chromium contents in the liver and kidney of the mice injected with Cr(III) were lower than those injected with Cr(VI) during the experimental period. (3) Increases of TBARS formation in the liver, chromium content in the liver and kidney, and ornithine carbamyl transferase (OCT) activity indicative of the liver cell damage, and urea nitrogen content in the serum, indicative of the kidney damage, observed at 24 hr after injection of Cr(VI) were inhibited by simultaneous injection of 100 mg/kg of L-ascorbic acid, as antichrome agent, respectively. These observations might suggest a possible causative role of lipid peroxidation in Cr(VI) toxicity.(ABSTRACT TRUNCATED AT 250 WORDS)