Overwintering of brown leaf spot fungus, Mycochaetophora gentianae, in infected gentian leaves as the primary inoculum source

Overwintering of the brown leaf spot fungus, Mycochaetophora gentianae, in infected gentian leaves was studied in Iwate, northern Japan. Sporophores were produced on overwintered, infected leaves when they were sampled from January to July, but not in August after incubation in high humidity at 15 °C. Symptoms developed on gentian plants grown in soil artificially infested with overwintered, infected leaves that were either left throughout the experiments or removed before planting. Few lesions developed when plants were grown in soil infested with conidia. These results indicate that M. gentianae can overwinter in infected leaves, which act as the primary inoculum source.     

Mechanism underlying potato spindle tuber viroid affecting tomato (Solanum lycopersicum): loss of control over reactive oxygen species production

Journal of General Plant Pathology - Severe infection of the tomato cultivar ‘Rutgers’ with potato spindle tuber viroid (PSTVd) variants resulted in systemic stunting, leaf...     

The activity of matrix metalloproteinases (MMPS) and tissue inhibitors of metalloproteinases (TIMPs) in mammary tumors of dogs and rats

We conducted zymography for detecting the activity of matrix metalloproteinases (MMPs) and reverse zymography for the activity of tissue inhibitors of metalloproteinases (TIMPs) in canine spontaneous and rat 7, 12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumor tissues. The activities of MMPs of canine mammary tumors were quite higher than those of the rat chemically induced tumors. The activities of MMPs were significantly higher in malignant tissues than in benign ones of canine tumors, whereas the activity of only MMP-2 was higher in both benign and malignant rat tumors compared to normal tissues. There were no differences of MMPs activities between benign and malignant rat tumors. The results of reverse zymography indicated that the activities of TIMP-1, -2 and -3 were strikingly higher in rat tumors than in canine tumors. The activities were higher in malignant tissues than in benign ones of dogs, and higher in tumor tissues than in normal mammary tissues of rats. The results of film in situ zymography for tissue localization of gelatinolytic activity showed that the digested area was more extended in malignant tumors than in benign ones of dogs. However, the area was similarly extended in both benign and malignant rat tumors. These results may indicate that the canine spontaneous malignant mammary tumors possess more aggressive nature than the rat chemically induced counterpart, resulting from the high level of MMPs and low level of TIMPs activities of the tumor tissues.     

Effect of an automatic milking system on milking traits

Recent studies in Japan of the effect of automatic milking systems (AMS) on the behavior of dairy cows have confirmed the labor-saving aspect of AMS, but have not solved some of the problems affecting milking traits. The influence of AMS on milking was examined in 39 Holstein cows at Iwate Agricultural Research Center from June 1998 to December 1999, by measuring and recording the yield per milking, milking finish time, milking frequency, and daily yield of milking. Four milking traits were analyzed separately as the objective variable in a linear model, with parity, days in milking, month after installation of the AMS as independent variables. Primiparous cows milked more frequently in the middle and late stage of lactation, yielded less per milking and less per day in the early stage of lactation than multiparous cows with the AMS. Lower frequencies were observed at noon and midnight for cleaning of the bulk tank. By contrast, higher milking frequency in the forenoon was shown. The yield per milking rose and declined, following a normal lactation curve. However, milking frequency rose slowly, and declined gradually in the late stage of lactation. After installing a one-way gate, the cows milked more frequently, with a lower yield per milking and a greater daily milk yield, than before installation.     

AFLP analysis of diploid species in the genus Vigna subgenus Ceratotropis

A representative set of germplasm of genusVigna subgenus Ceratotropis specieswas used to analyze genetic diversity using amplified fragment lengthpolymorphism (AFLP) methodology. The germplasm was selected based onmorphological diversity and geographic origin and includes 18 out of the 21species in the subgenus Ceratotropis. Genetic diversitywithin and between taxa was measured using information generated by AFLP bandpolymorphism from which Jaccard's similarity coefficient and nucleotidediversity were estimated. The data were also used to generate phenograms tovisualize relationships among analyzed accessions. All species in sectionsCeratotropis and Aconitifoliae arewell separated. However, most of the species in sectionAngulares show a high level of similarity suggesting a lowlevel of genetic differentiation. In section Angulares onespecies, V. trinervia, is welldifferentiated from the other species and represents a separate evolutionarybranch between section Ceratotropis and other species insection Angulares. The relationships between the newlydescribed species V. aridicola,V. exilis, V.nepalensis and V.tenuicaulis and other species in the subgenusCeratotropis are described for the first time based on AFLPdata.     

Tyrosinase inhibitor from black rice bran

The inhibitor of tyrosinase activity in black rice bran was investigated. The methanol extract from black rice bran was re-extracted with hexane, chloroform, ethyl acetate, or water. The ethyl acetate extract had the most potent inhibition against tyrosinase activity by 80.5% at a concentration of 0.4 mg/mL. Inhibitory compound in the ethyl acetate fraction was isolated by silica gel column chromatography, and identified as protocatechuic acid methyl ester (compound 1) by GC, GC-MS, IR, and 1H and 13C NMR spectroscopy. Compound 1 inhibited 75.4% of tyrosinase activity at a concentration of 0.50 micromol/mL. ID(50) (50% inhibition dose) value of compound 1 was 0.28 micromol/mL. To study the structure-activity relationship, protocatechuic acid (2), vanillic acid (3), vanillic acid methyl ester (4), isovanillic acid (5), isovanillic acid methyl ester (6), veratric acid (7), and veratric acid methyl ester (8) were also assayed.     

Evaluation of iron bioavailability from bonito dark muscle using anemic rats

The bioavailability of iron from ferrous sulfate (FeII-S), heme iron prepared from hemoglobin (HIP), and bonito dark muscle (BDM) was assessed in anemic rats using a hemoglobin regeneration efficiency (HRE) method. Freeze-dried BDM (FD), boiled and freeze-dried BDM (B/FD), and boiled and smoke-dried BDM (B/SD) were used as BDM source. Rats were made anemic by feeding on an iron-deficient diet for 28 days. To replete their iron levels, anemic rats were then fed on a diet containing iron at a level of 17 ppm for 14 days. Rats receiving FeII-S gained significantly more weight and had greater food intake and higher HRE compared to the other four groups. The bioavailability of iron from HIP was poor compared with that from FeII-S and BDM. When the HRE of rats fed FeII-S was 100, that of rats fed BDF was approximately 80. These results suggest that BMD is an effective dietary source of iron.     

Inhibitory activity of corn-derived bisamide compounds against alpha-glucosidase

Bioassay guided fractionation from corn gluten meal, a byproduct of a starch manufacturing plant, gave N-p-coumaroyl-N'-feruloylputrescine (1) and N,N'-diferuloylputrescine (2) as alpha-glucosidase inhibitors. Some structure-activity relationships were studied by comparing the inhibitory activity by preparing some related compounds, and it was revealed that the hydroxyl group was important for the inhibitory activity of bisamide alkaloids, but not the redox potential.