Analysis of the function of activin betaC subunit using recombinant protein

Activins, TGF-beta superfamily members, have multiple functions in a variety of cells and tissues. Additional activin beta subunit genes, betaC and betaE, have been identified in humans and rodents. To explore the role of activin betaC subunit, we generated recombinant human activin C using Chinese hamster ovary cells. Recombinant activin C from the conditioned medium was purified by consecutive hydrophobic, size-exclusion, and high performance liquid chromatography. SDS-PAGE and Western blot analysis of the purified protein revealed that activin C formed disulfide bridges. However, activin C had no effect on the proliferation of cultured liver cells. Furthermore, there were no significant differences in erythroid differentiation and follicle stimulating hormone secretion in vitro. It was also shown that immunoreactive bands indicated the hetrodimer of activin betaC, and inhibin alpha subunits were detected in the conditioned medium from the activin C-producing cells, which were stably transfected with inhibin alpha subunit cDNA. This suggests that activin betaC subunit may have been present and that it may exert its effect as inhibin C.     

叶面喷施寡糖对生菜生长和品质的调节作用

为探究不同单一寡糖和复配寡糖对作物生长发育、产量及品质的影响,选择生长周期较短的生菜品种“意大利耐抽薹”作为研究对象,以80mg·L-1的纤维寡糖（ZH-A）、低聚木糖（ZH-B）、甲壳低聚糖（ZH-C）和以上3种寡糖等质量比的复配寡糖（ZH-M）以及多糖海藻酸钠（GY-D）对定植后的生菜进行4次叶面喷施处理,以喷清水为对照（CK）。从定植后的第3天（三叶一心）开始,每隔2d连续喷施4次,至采收期（定植23d）测定生菜的生长特征（生物量、叶面积、荧光光合）、根系表型特征（根长、根表面积、根体积）以及品质特征（可溶性糖、叶绿素、Vc、硝酸盐）。结果表明：单一寡糖、复配寡糖及海藻酸钠多糖处理均能显著增加生菜生物量;纤维寡糖（ZH-A）对促进根系生长及降低硝酸盐含量具有显著效果;甲壳低聚糖（ZH-C）对叶绿素含量、最大光化学效率Fv/Fm及可溶性糖含量有显著的提高作用;复配寡糖对生菜地上部、地下部及品质的增长和提升效果明显优于单一寡糖和多糖,采收期地上部鲜重及叶面积分别增加52.58%和57.60%,根干重、总根长、总体积及总表面积分别增加35.07%、89.10%、49.23%和40.68%,可溶性糖增加25.20%,叶绿素含量增加21.50%,Vc含量提高12.08%,硝酸盐含量降低27.65%。综上可知,不同寡糖对生菜生长特征和生理性状的作用效果和调控机制具有明显差异;复配寡糖对生菜促生长和提品质的调节效果显著优于单一寡糖。     

New lactic acid bacteria for skin health via oral intake of heat‐killed or live cells

Lactic acid bacteria play an essential role in the food industry in the manufacture of many fermented products (cheese, yogurt, fermented vegetables, etc.). Application of these organisms is now being extended to the area of health improvement, as their probiotic activities become known. Probiotics are defined as viable microorganisms that exert a beneficial effect on the health of the host when they are ingested in sufficient quantity. Lactic acid bacteria and bifidobacteria isolated from the human intestine are the most common probiotics used for human consumption. The development of new probiotics with new beneficial effects is eagerly awaited in the food industry. This review introduces Lactococcus, which are one of the genera of lactic acid bacteria and are mainly isolated from dairy products and fermented vegetables, as new probiotics, focusing especially on Lactococcus lactis H61, which improves skin status in Japanese women with oral intake of heat‐killed or live cells. The deduced mechanisms associated with the beneficial effects of strain H61 are also discussed.     

Influence of volcanic ash sediments on spore adhesion of the red alga Gelidium elegans from the coastal seabed around Miyakejima Island, Japan

The populations of red alga Gelidium elegans along the coast of Miyakejima Island were severely damaged by a volcanic eruption in 2000. The effect of this volcanic eruption has been long lasting, and populations of this red alga still have not recovered. We investigated the effect of seabed sediment particles derived from volcanic ash on the substrate adhesion of G.?elegans spores. The analysis provides evidence that increasing amounts of sediment particles result in lower adhesion rates of G.?elegans spores, and that smaller sediment particles have a greater influence on adhesion. The amount of seabed sediment particles around Miyakejima Island was 9.3?C1815.4?mg/cm². This amount has changed greatly from year to year. The adhesion rate of G.?elegans spores in water around Miyakejima Island was 0?% at all points in 2008 and 2010, but it was estimated as 6.3?C38.6?% in 2009. These results suggest that there is significant inhibition of algal spore adhesion by seabed sediment particles derived from volcanic ash around Miyakejima Island.     

Spontaneous Malignant T Cell Lymphoma in a Young Male Common Marmoset (Callithrix jacchus)

We histopathologically and immunohistochemically investigated a case of malignant lymphoma that spontaneously developed in a male common marmoset at two years of age. Beginning at two years four months of age, the animal had an enlargement of the submandibular and inguinal lymph nodes, small subcutaneous nodules near the right breast and an approximately fivefold increase in peripheral lymphocyte count compared with the previous examination value. The postmortem findings at two years eight months of age showed lymphadenopathy with enlargement of the thymus and spleen. Small- to intermediate-sized neoplastic lymphocytes had diffusely proliferated in the enlarged nodes. The neoplastic cells were pleomorphic and had irregularly shaped nuclei. The nuclear chromatin staining revealed hyperchromatism in the small-sized cells, and the intermediate-sized cells exhibited vesicular staining. An immunohistochemical examination indicated that the neoplastic lymphocytes were positive for CD3 and negative for CD20, thus suggesting that they had originated from T cells. In addition, the proliferation of high endothelial venules and reactive epithelioid histiocytes was observed. Scattered tingible body-laden macrophages were infrequently detected. Neoplastic lymphocytes were also observed in the thymus, spleen, heart, lungs, liver, kidneys, adrenal glands and femoral and sternal bone marrow. This malignant lymphoma in a young male common marmoset was considered to fit the category of “peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS)” according to the new WHO system of classification.     

Influences of human activities on sediment discharge from devastated weathered granite hills of southern China: effects of 4-year elimination of human activities

Sediment discharge is a serious problem in the weathered granite mountains of southern China. Human activities, such as the harvesting of ferns and litter for fuel, are the main source of sediment, but the details of the processes and mechanisms leading to sediment discharge are unclear. Data on sediment yields, percentages of peak storm runoff and fern undergrowth and litter cover extent in the two basins—one a control from which people have been excluded since 1997, and the other where normal harvesting practices are permitted—were used to evaluate how human activity affects sediment discharge. The annual sediment discharge decreased immediately after implementing control practice, despite no marked changes in the 4 years after 1997 in the percentages of peak storm turnoff and the fern and litter cover extent and density. The 4-year period of control practice was too short to affect the relationship between peak rainfall and peak storm runoff and the fern and litter covers and their amounts, but long enough to contribute to the reductions in sediment discharge in the control basin by decreasing erodibility. Thus, sediment discharge was probably reduced to some extent by the elimination of human impacts even though a well-developed vegetation layer did not develop.     

Effects of time,temperature, and humidity on acetaldehyde emission from wood-based materials

Acetaldehyde emissions from particleboard, fiberboard, and plywood were studied using the small chamber method and high-performance liquid chromatography analysis. The chamber tests were conducted for 1 month to examine the time dependence of acetaldehyde emission. Effects of temperature and relative humidity were also examined. Acetaldehyde emissions from these wood-based materials decreased rapidly and their behavior could be described by an exponential function or by the sum of two exponential functions. This result suggests that in an adequately ventilated atmosphere, the acetaldehyde emission factor decreases quickly following the board’s production. Under fixed absolute humidity conditions, the initial acetaldehyde emission factor was larger under higher temperature conditions, but tended to show almost the same value after 14 days. This suggests that higher temperatures promote higher initial concentrations and a faster decline of acetaldehyde. A semi-empirical linear equation was obtained for the early stage relationship between the emission factor and temperature. Under fixed temperature conditions, higher relative humidity caused a larger acetaldehyde emission factor throughout the testing period, and it did not result in a significantly faster decline in emissions. The relationship between acetaldehyde emission and relative humidity can be described using an exponential function.     

Effect of sodium acetate on the adhesion to porcine gastric mucin in a Lactococcus lactis strain grown on fructose

The association of lactic acid bacteria with mucosal surfaces plays important roles in the beneficial effects of these bacteria on human health, such as colonization of the gastrointestinal tract for pathogen antagonism. Previously, we found that the adhesion of Lactococcus lactis 7‐1 to porcine gastric mucin was higher with fructose than with lactose, galactose or xylose as the carbon source. In this study, we examined the effect of growth conditions on the adhesion of strain 7‐1 grown on fructose. Medium components affect the adhesion: the adhesion of strain 7‐1 grown with sodium acetate was higher than that without it. The enhancement of adhesion by sodium acetate was not observed under aerobic conditions. Cellular properties grown with or without sodium acetate were characterized: strain 7‐1 grown with sodium acetate had similar sugar contents, and different fatty acid composition to those grown without it. Strain 7‐1 grown with sodium acetate showed significantly lower cell yield and significantly higher hydrophobicity than those grown without it, which is associated with higher adhesion. Fructose and sodium acetate are frequently used in the food industry; this study may reveal a simple way to enhance the adhesion of lactic acid bacteria by growing them with these substances.     

Acoustic pressure sensitivities and effects of particle motion in red sea bream Pagrus major

The auditory pressure thresholds of red sea bream were examined using cardiac response in the field by placing fish subjects far from the sound source to prevent particle motion. Pressure and particle motion thresholds were also obtained using the auditory brainstem response (ABR) technique. The thresholds at 100 and 200 Hz were significantly higher when measured using the cardiac response in the far field than those obtained in previously conducted experiments in experimental tub. However, thresholds obtained using ABR from 200 to 500 Hz were not remarkably lower, although significantly different (0.01 < P < 0.05), compared with those obtained using cardiac response in the far field. Furthermore, calculated particle velocity thresholds indicated that fish probably detected particle motion within the frequency range of 50–200 Hz, even in fish with a deactivated lateral line. Although the ABR method is widely applied in fish auditory study, hearing thresholds are apparently affected by particle motion.