MicroRNAs as tumour suppressors in canine and human melanoma cells and as a prognostic factor in canine melanomas

Malignant melanoma (MM) is one of the most aggressive cancers in dogs and in humans. However, the molecular mechanisms of its development and progression remain unclear. Presently, we examined the expression profile of microRNAs (miRs) in canine oral MM tissues and paired normal oral mucosa tissues by using the microRNA‐microarray assay and quantitative RT‐PCR. Importantly, a decreased expression of miR‐203 was significantly associated with a shorter survival time. Also, miR‐203 and ‐205 were markedly down‐regulated in canine and human MM cell lines tested. Furthermore, the ectopic expression of miR‐205 had a significant inhibitory effect on the cell growth of canine and human melanoma cells tested by targeting erbb3. Our data suggest that miR‐203 is a new prognostic factor in canine oral MMs and that miR‐205 functions as a tumour suppressor by targeting erbb3 in both canine and human MM cells.     

Rainfall-runoff responses and roles of soil moisture variations to the response in tropical rain forest, bukit tarek, peninsular Malaysia

Field observations were conducted at Bukit Tarek Experimental Watershed in Peninsular Malaysia to investigate the relationship between rainfall-runoff responses and variation in soil moisture in a tropical rain forest. Stormflow depended strongly on the antecedent wetness as represented by the initial runoff rate. Though heavy rains fell in almost every month, the soil moisture decreased when fair weather was sustained. The soil moisture depleted and became dry at 160 cm depth during occasional dry spells. During dry conditions, streamflow responded quickly to rain events but declined rapidly after the rain stopped, and the soil moisture of surface soil (≤20 cm) increased but remained dry at lower depths (≽80 cm). This suggests that the rain water was mostly retained in the soil and only small proportions appeared as stormflow. As soil moisture conditions became wetter, the recession limb of the storm hydrograph was more gradual. Stormflow volume increased with increasing soil moisture. During wet conditions, the soil profile was moist at all parts of the slope. The hydraulic gradient was around 1.0 and there was downward soil water flux, which followed the pressure gradient. This suggests that subsurface flow from the upper part of the slope might also be important for stream-flow production. Positive pressures were observed at 10 cm and 160 cm depths during large storms. The behavior of the subsurface flow might be an important determinant of stormflow.     

Measurement of porcine luteinizing hormone concentration in blood by time-resolved fluoroimmunoassay

We validated a time-resolved fluoroimmunoassay (TR-FIA) using the lanthanide element europium as a non-radiological tracer for measuring luteinizing hormone (LH) in porcine peripheral blood. The dose-response curve of the reference standard ranged from 0.2048 to 50 ng/ml. Good parallelism was noted between the LH standard and plasma sample. The profile of LH throughout the estrous cycle, assessed by daily blood sampling, was consistent with the previous findings obtained by radioimmunoassays (RIAs). Moreover, the secretory patterns of pulsatile LH in the follicular phase and the preovulatory LH surge were also similar to those obtained in previous RIAs. We conclude that TR-FIA can be used to measure LH levels in porcine blood, with practical and convenient applications.     

Production of inhibin A and inhibin B in boars: changes in testicular and circulating levels of dimeric inhibins and characterization of inhibin forms during testis growth

We investigated the production of inhibin in boars from the infantile to pubertal periods by: (1) measurement of testicular and circulating levels of inhibin, (2) characterization of inhibin forms and (3) localization of inhibin subunits in the testis. Total inhibin levels in the testis increased until 8 weeks of age but then declined to much lower values at 15 weeks. Testicular inhibin A and inhibin B were high until 8 weeks. Circulating levels of total inhibin and inhibin A were also high until 8 weeks, then declined from 10 weeks; inhibin B was not detected, because of low sensitivity of the inhibin B assay. Analyses of inhibin A and inhibin B levels in the eluted fractions obtained from testes after immunoaffinity chromatography and SDS-PAGE showed the presence of a peak of approximately 45 kDa until 10 weeks of age. As the boars aged, the levels of inhibin A and inhibin B increased in the molecular weight region of 29–31 kDa. The fractions corresponding to 29 and 30 kDa suppressed FSH release from rat pituitary cells, but the 45 kDa fraction had no FSH-suppressing activity. Total amounts of inhibin A isolated from the SDS gels were similar to those of inhibin B until 10 weeks of age, but were three times higher than those of inhibin B between 15 and 25 weeks. Further fractionation by reverse phase high-performance liquid chromatography revealed that the 29–31 kDa immunoreactive material was composed of mature forms of inhibin A and inhibin B, in addition to a 26 kDa monomer. Immunohistochemistry indicated that positive immunostaining for the subunits was observed in Sertoli cells from the infantile to pubertal periods. Elongated spermatids also showed positive signals at age 25 weeks. These results clearly indicated that: (1) the boar testis has the ability to produce inhibin A and inhibin B during the infantile period but inhibin A is the predominant form towards puberty and (2) the molecular weight forms of inhibin and the sites of production of inhibin change with testicular development.     

Springiness of Pancake and Its Relation to Binding of Prime Starch to Tailings in Stored Wheat Flour

Wheat flours were stored at room temperature (15–25°C), 40, 60, 80, and 100°C for various times. The baking performance of these flours was then evaluated in terms of the springiness of pancakes (recovery from crushing). Baking performance improved with increased storage time at each temperature. Brabender Amylograph tests of the flours indicated that the onset temperature in viscosity decreased with increased storage time at each temperature. When the flours were fractionated by acetic acid (pH 3.5) with mortar and pestle, recoveries of the water-solubles and gluten fractions were unchanged, but recoveries of prime starch and tailings fractions changed remarkably with increased storage time. On the other hand, those changes were not observed when flours were fractionated with a Waring blender. The binding of prime starch to tailings was correlated significantly with baking performance.     

Understanding why farmers plant trees in the homestead agroforestry in Bangladesh

Because trees cover only 6.4% of the total land area of Bangladesh, while agricultural expansion continues to massively deplete the natural forests, a well-managed homestead forestry practice is vital for reversing the existing trend and promoting the ecological balance of the country. An understanding of the decision-making process of the farmers who practice homestead forestry is important in expanding and improving the practice. This paper seeks to characterize and analyze factors influencing farmers' decisions about tree planting. Logistic and multiple regression analyses were applied to determine the factors that influence the farmers' tree-planting decisions. The analyses demonstrate a number of important conclusions: (i) tree-planting increases with the amount of homestead land owned; (ii) farmers whose main source of income is non-agricultural are more likely to decide to plant trees in the homestead; (iii) purchasing cost of fuelwood has a positive influence on tree-planting decisions; (iv) number of male family member has a positive influence on farmers' tree-planting decisions; and (v) knowledge of the activities of the forestry extension programs has a positive influence on tree-planting decisions. The results of the study demonstrate that, in recent years, farmers' decisions of whether or not to plant trees have been based primarily on economic rather than ecological concerns. It is concluded that there is substantial potential for the improvement of homestead forestry, and that properly managed homestead forestry can alleviate the poverty of rural people by increasing overall household income. To this end, it is suggested that forestry extension workers work more closely with the local people in order to implement homestead forestry.This revised version was published online in November 2005 with corrections to the Cover Date.     

Individual-scale responses of five dominant tree species to single-tree selection harvesting in a mixed forest in Hokkaido, northern Japan

We investigated the individual-scale responses of five dominant species (Abies sachalinensis, Acer mono, Tilia japonica, Quercus crispula, and Betula ermanii) to single-tree selection harvesting in a conifer–broadleaved mixed forest in Hokkaido, northern Japan. Using data from stems with a diameter at breast height of ≥12.5 cm, collected during 20 years of monitoring a 6.7-ha stand, we analyzed the effects of harvesting in the neighborhood on tree recruitment and the growth (diameter class transition) and mortality of the residual trees. The effects of harvesting varied considerably among tree sizes and species. Harvesting improved the recruitment of A. mono and B. ermanii, and moderated the negative effect of the initial basal area of the surrounding canopy trees on the recruitment of Q. crispula. Conversely, harvesting limited the recruitment of A. sachalinensis by offsetting the positive effect of the initial basal area of the surrounding canopy trees. The growth of A. sachalinensis and Q. crispula decreased with the initial basal area of the surrounding canopy trees. Harvesting in the neighborhood resulted in an improvement in the growth of the trees of these species only in the smaller size classes. With increasing local harvesting intensity, the mortality of smaller A. sachalinensis trees decreased, whereas the mortality of larger trees increased. These results suggest that differences in the local harvesting intensity, spatial patterns of harvesting, and initial stand structures influence the stand-scale dynamics in response to partial harvesting in the mixed forests of this region.     

Individual growing conditions that affect diameter increment of tree saplings after selection harvesting in a mixed forest in northern Japan

We analyzed temporal patterns in diameter growth of saplings following selection harvesting in an uneven-aged mixed stand dominated by Abies sachalinensis, Acer mono, Quercus crispula, and Betula ermanii in Hokkaido, northern Japan. We examined interspecific differences in growth responses to local growing conditions including harvesting intensity, crowding, stem size, and past duration of the small growth period. Consistent with expectations based on shade tolerance of the species, the age at which the individual reached a diameter at breast height (DBH) of 12.5 cm was highest for A. sachalinensis and lowest for B. ermanii. The interspecific growth differences between saplings that had or had not experienced local harvesting increased gradually for A. sachalinensis and B. ermanii, but peaked at around 4–6 years after harvesting for Q. crispula. Generalized linear mixed model analysis clearly suggested that individual growth conditions required to enhance diameter growth of saplings differed considerably among species. For Q. crispula and B. ermanii, local harvesting intensity was most strongly and positively associated with diameter growth rate, whereas for A. sachalinensis and A. mono, stem size had the strongest negative effect. Abies sachalinensis saplings responded more to surrounding harvesting when they were relatively small, whereas A. mono showed a weak opposite response. The duration of the small growth period before harvesting had negative effect for A. sachalinensis, but not for the other species. Our study indicated that the influence of selection harvesting on growth of shade-tolerant species depends upon pre- and post-harvest growing conditions.     

Inhibition of Df-protease associated with allergic diseases by polyphenol.

It was reported that Df-protease from house dust mite (Dermatophagoides farinae) catalyzes the activation of the kallikrein-kinin system in human plasma and is closely associated with mite-induced allergy. Therefore, to prevent the release of kinin by Df-protease, the inhibitory activity of polyphenols including catechins and flavonols was tested in vitro and in vivo. Among them, myricetin and epigallocatechin gallate (EGCg) effectively inhibited the amidase activity of Df-protease with K(i) values of 1 x 10(-)(8) and 6 x 10(-)(4) M, respectively. The kinin release in human plasma was extensively inhibited by the addition of EGCg in comparison with myricetin. Enhancement of vascular permeability in guinea pigs caused by Df-protease was markedly suppressed by EGCg.