Demonstration of cytotoxic lymphocytes to virus-infected target cells in pigs inoculated with transmissible gastroenteritis virus.

Lymphocytes, cytotoxic to virus-infected target cells, were induced in pigs orally exposed to transmissible gastroenteritis virus. They were studied and experiments were carried out by using autochthonous testicle cells as target cells to avoid genetic incompatibility of effector lymphocytes and target cells. Cytotoxic lymphocytes were demonstrated in Peyer's patches, mesenteric lymph nodes, spleen, and peripheral blood on postinoculation day (PID) 7. Cytotoxic activity of lymphocytes increased thereafter and reached the maximal amount at PID 21. Lymphocyte cytotoxicity was somewhat greater in lymphocytes of peripheral blood and spleen than in those of Peyer's patches and mesenteric lymph nodes after PID 14. On the contrary, lymphocyte reactivity to the viral antigen measured by lymphocyte proliferative assay was higher in Peyer's patch and mesenteric lymph node cells than in peripheral blood and splenic cells. Lymphocyte cytotoxicity was depressed by treating effector cells with anti-porcine thymocyte serum and complement. However, lymphocyte suspensions treated with anti-porcine thymocyte serum and complement were still cytotoxic to some extent against virus-infected target cells, although T lymphocytes were completely excluded by the treatment. This suggests that cytotoxic mechanism other than the direct action of cytotoxic T lymphocytes may be involved in the cytotoxicity assay systems used in the present studies. In experiments in which allogenic cells (testicle cells of siblings) were used together with autochthonous cells as targets, lymphocyte cytotoxicity was equally expressed against both autochthonous and allogenic target cells in 2 of 3 experiments. However, lymphocyte cytotoxicity was greater against autochthonous cells than against allogenic target cells in 1 of 3 experiments.     

Damping-off of cabbage plug seedlings caused by Pythium ultimum var. ultimum in Japan

In October 2004, Pythium ultimum var. ultimum was isolated from rotten stems of cabbage plug seedlings in a commercial nursery in Mie Prefecture (Japan). The isolated fungus was then used to inoculate seedlings and subsequently reisolated from the seedlings with the damping-off disease, showing that P. ultimum var. ultimum is a new pathogen causing cabbage seedling disease.     

Multiplication of isolate R-5 of <Emphasis Type="Italic">Streptomyces galbus</Emphasis> on rhododendron leaves and its production of cell wall-degrading enzymes

 An endophytic actinomycete, isolate R-5 of Streptomyces galbus Frommer, that has promising potential as a biocontrol agent was originally isolated from field-grown rhododendron. In this study, the mode of entry of R-5 into leaves of tissue-cultured seedlings of rhododendron was investigated in connection with its production of cell wall-degrading enzymes. Light and scanning electron microscopy (SEM) revealed that R-5 grew on leaf surfaces and entered leaf tissues via stomata and that the internal mycelia grew out of stomata after colonization in host tissues. Micromanipulation at the SEM level demonstrated a prominent depression in the host surface at the interfaces with the mycelia, suggesting that such a depression could be caused by degradation of cell wall components by hydrolytic enzymes secreted from R-5 mycelia. In subsequent plate assays, R-5 produced cellulase, pectinase, xylanase, and nonspecific esterase when cultured in liquid medium. Moreover, R-5 multiplied in mineral medium containing cellulose, pectin, or xylan as a single carbon source. Thus, R-5 mycelia could degrade host cell walls at contact sites and probably utilize the degradation products as carbon sources. Received: May 16, 2002 / Accepted: July 9, 2002     

Physiological levels of C-reactive protein in normal canine sera

This study was undertaken to investigate whether the level of C-reactive protein (CRP) in the serum of dogs undergoes physiological variation, using 10 normal Beagle dogs (5 males and 5 females), 1–2 years old, maintained in a healthy condition in a controlled environment. The CRP concentration in the sera collected seven times each day at intervals of approximately 3 h ranged from 0.8 to 16.4 µg/ml (mean 5.06±3.60) in one experiment and from 0.8 to 14.0 µg/ml (mean 4.50±2.80) in a second experiment. On examining the 24-h variations in the concentration of CRP in serum, neither consistent changes nor a definite pattern of circadian rhythm was detected. During 28 days observation, only very slight changes, which seemed attributable to analytical errors, were seen in any of the dogs, except one. The concentration of CRP in the serum during the 28 days ranged from 0.8 to 22.6 µg/ml (mean 3.65±1.40). The concentrations underwent no significant variations in individual dogs, but significant differences were found between the dogs (p<0.01).     

施肥对不同种植模式下春玉米光合特性的影响

建立了一种密度与单作相同的超大宽窄行种植模式。通过小区试验,研究了该模式下施肥对春玉米单株叶面积、净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)及光响应曲线的影响,比较了该模式与单作模式玉米光合特性的异同。结果表明,随着施肥量的增加,Pn、Gs、Ci和单株叶面积都有增加趋势。间作玉米与单作玉米相比,玉米的单株叶面积表现为间作在生育前期小于单作,但在灌浆期及以后的生育时期单作下降较快,表现出间作明显大于单作;玉米叶片Pn生育前期单作较高,但生育后期间作明显高于单作。叶片光响应曲线及其拟合结果也表明,间作前期的最大净光合速率和表观量子效率均小于单作,生育后期大于单作。本试验表明,超大宽窄行种植模式有助于玉米生育后期光合条件的改善。     

Isoprenoid-substituted flavonoids from wood of Artocarpus heterophyllus on B16 melanoma cells: Cytotoxicity and structural criteria

As a result of cytotoxicity-guided fractionation, nine flavonoids, artocarpin (1), cudraflavone C (2), 6-prenylapigenin (3), kuwanon C (4), norartocarpin (5), albanin A (6), cudraflavone B (7), brosimone I (8) and artocarpanone (9) were identified from the methanol extract of the wood of Artocarpus heterophyllus, known commonly as Nangka in Indonesia. A structure–activity investigation of the effect of these isolated compounds (1–9) and structurally related compounds on B16 melanoma cells indicated that isoprenoid moiety substitutions in flavonoids enhance their cytotoxicity, and that the position of attachment and the number of isoprenoid-substituent moieties per molecule influence flavonoid cytotoxicity.     

Development of acid soil conditioning agent from lignin by ozone treatment I

A purified softwood kraft lignin was modified by ozone treatment and its activity as an acid soil conditioning agent, mainly focusing on elimination of aluminum toxicity, was assayed by planting experiments. The growth of radish root was examined in nutrient solution containing CaCl₂ and AlCl₃ at pH 4.8 with and without modified kraft lignins. The modified kraft lignins that absorbed 1.8 and 3.9 moles of ozone per C6-C3 unit (M _w 180) showed two effects: the elimination of aluminum toxicity and the acceleration of root growth. The effect on the elimination of aluminum toxicity was observed even with modified kraft lignin that absorbed 1.0 mole of ozone per C6-C3 unit. The high molecular weight part of the modified kraft lignin that absorbed 3.9 moles of ozone per C6-C3 unit also proved to be effective not only in elimination of aluminum toxicity but also in acceleration of root growth. The acceleration effect of ozone-treated lignins on root growth was also observed under the absence of aluminum in planting experiments. This report was presented in part at the 56th Annual Meeting of the Japan Wood Research Society, Akita, Japan, August 2006     

Nested PCR‐RFLP is a high‐speed method to detect fungicide‐resistant Botrytis cinerea at an early growth stage of grapes

BACKGROUND: Grey mould caused by the fungus Botrytis cinerea Pers. ex Fr. is one of the major diseases in grapes. The use of fungicides is a simple strategy to protect grapes against B. cinerea disease. However, phenotypes exhibiting resistance to fungicides have been detected in B. cinerea populations. The variation of fungicide‐resistant B. cinerea isolates renders B. cinerea disease control difficult in grapevine fields. RESULTS: The authors have developed a nested polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) method to detect fungicide‐resistant B. cinerea isolates at an early growth stage of grapes in grapevine fields. The nested PCR‐RFLP method was carried out to detect benzimidazole‐, phenylcarbamate‐ and/or dicarboximide‐resistant B. cinerea isolates from grape berries and leaves at Eichorn–Lorenz growth stage 25 to 29. This method successfully detected fungicide‐resistant B. cinerea isolates at an early growth stage of grapes. In addition, only 8 h was required from tissue sampling to phenotyping of fungicide resistance of the isolates. CONCLUSION: It is proposed that the early diagnosis of fungicide‐resistant B. cinerea isolates would contribute to further improvement of integrated pest management against B. cinerea in grapevine fields, and that the nested PCR‐RFLP method is a high‐speed, sensitive and reliable tool for this purpose. Copyright © 2008 Society of Chemical Industry     

Effect of High β-Glucan Barley on Serum Cholesterol Concentrations and Visceral Fat Area in Japanese Men—A Randomized,Double-blinded,Placebo-controlled Trial

This study investigated whether the consumption of a diet in which high-β-glucan barley replaced rice would reduce the visceral fat area as well as the serum low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) in hypercholesterolemic Japanese men. A randomized, double-blinded, placebo-controlled intervention study was conducted in 44 hypercholesterolemic Japanese men with a body mass index (BMI) >22 kg/m². The subjects were randomly assigned to groups consuming either rice (placebo group) or a mixture of rice and pearl barley with a high β-glucan content (test group, 7.0 g β-glucan per day) for 12 weeks. Blood samples were taken, and CT scan obtained before the trial and every four weeks during the trial. The pearl barley intake significantly reduced serum concentrations of LDL-C (P = 0.041) and TC (P = 0.037) during the trial. Significant differences between the test and placebo groups were found for the visceral fat (P = 0.039), BMI (P = 0.015), and waist circumference (P = 0.011) at the end point. The consumption of pearl barley with a high β-glucan content reduces not only LDL-C but also visceral fat area.