Expression of interleukin-10 activity by Epstein-Barr virus protein BCRF1

Cytokine synthesis inhibitory factor (CSIF; interleukin-10), a product of mouse TH2 T cell clones that inhibits synthesis of cytokines by mouse TH1 T cell clones, exhibits extensive sequence similarity to an uncharacterized open reading frame in the Epstein-Barr virus BCRF1. Recombinant BCRF1 protein mimics the activity of interleukin-10, suggesting that BCRF1 may have a role in the interaction of the virus with the host's immune system.     

Magnetoreception in honeybees

Magnetoreception by honeybees (Apis mellifera) is demonstrated by such activities as comb building and homing orientation, which are affected by the geomagnetic field. In other magnetoreceptive species, iron oxide crystals in the form of magnetite have been shown to be necessary for primary detection of magnetic fields. Here it is shown that trophocytes, which are apparently the only iron granule-containing cells in honeybees, contain super-paramagnetic magnetite. These cells are innervated by the nervous system, which suggests that trophocytes might be primarily responsible for magnetoreception. Electron microscopy also shows cytoskeletal attachments to the iron granule membrane.     

Neural systems responding to degrees of uncertainty in human decision-making

Much is known about how people make decisions under varying levels of probability (risk). Less is known about the neural basis of decision-making when probabilities are uncertain because of missing information (ambiguity). In decision theory, ambiguity about probabilities should not affect choices. Using functional brain imaging, we show that the level of ambiguity in choices correlates positively with activation in the amygdala and orbitofrontal cortex, and negatively with a striatal system. Moreover, striatal activity correlates positively with expected reward. Neurological subjects with orbitofrontal lesions were insensitive to the level of ambiguity and risk in behavioral choices. These data suggest a general neural circuit responding to degrees of uncertainty, contrary to decision theory.     

Association of the HL-A7 cross-reacting group with a specific reaginic antibody response in allergic man

A relatively small proportion (17 percent) of individuals highly allergic to ragweed were found to develop marked reaginic (immunoglobulin E-mediated) skin sensitivity to a minor ragweed pollen allergen Ra5 (molecular weight 5200). Sensitivity to Ra5 was significantly associated with the possession of a major histocompatibility antigen of the HL-A7 cross-reacting group. This appears to be the first evidence of a strong association between a specific immune response and a specific group of closely related HL-A antigens in man.     

Antiproliferative lactams and spiroenone from adlay bran in human breast cancer cell lines

Two new lactams, coixspirolactam D (1) and coixspirolactam E (2), and a new spiroenone, coixspiroenone (3), together with seven known compounds, coixspirolactam A (4), coixspirolactam B (5), coixspirolactam C (6), coixlactam (7), coixol (8), ethyl dioxindole-3-acetate (9), and isoindol-1-one (10), and two neolignans, zhepiresionol (11) and ficusal (12), were isolated from the bioactive subfraction of adlay bran ethanolic extract (ABE). Compounds 9 and 10 are the first isolates from natural resources. The structures of new compounds were identified by spectroscopic methods, including infrared (IR) spectrum, 1D and 2D nuclear magnetic resonance (NMR), and mass spectrum (MS). All of the isolated compounds were tested for antiproliferative effects on MCF-7, MDA-MB-231, and T-47D cells. Results showed that compounds 1, 3, 4, 6, and 7 at 50 μM significantly inhibited MCF-7 cell proliferation by 30.2, 19.2, 21.0, 13.5, and 32.4%, respectively; compounds 2, 4, and 7 significantly inhibited T-47D cells at 50 μM by 20.7, 24.8, and 28.9%; and compounds 1, 2, and 12 significantly inhibited MDA-MB-231 cells at 50 μM by 47.4, 25.3, and 69.3%, respectively. In conclusion, ABE has antiproliferative activities, and this effect is partially related to the presence of lactams and spiroenone.     

台东木坑溪集水区潜在崩塌评估准则之建立

 木坑溪集水区位于台东纵谷,为利吉层泥岩之代表地区,地质复杂,地层脆弱。该文依调查之地形、地质与土地利用现况等条件,参考相关学者对于潜在崩塌地评估之论述,进行访谈问卷之设计与调查统计,并作为研究之评估准则。研究结果得知,台东木坑溪集水区现有崩塌地之崩塌危险指数均属于危险等级,不宜随意开发利用。在进行问卷访谈时,区位因子并未被多数受访者所认同,然而现场调查结果却发现多数之崩塌其发生均与区位因子有相当之关联性,因此,该项目因子值得后续研究探讨。由于研究范围的限定,使得某些参数值并无太大差异,若将研究调查范围扩大,将会使得立地条件之影响更为显着。     

Scientific goals and experiments of the project “winter precipitation at Mount Rigi”: An overview

Wet deposition plays an important role as a mechanism for cleansing of the polluted troposphere. Fluxes of pollutants from the atmosphere to earth's surface can affect soil and aquatic ecosystems. The investigation of the pollutant incorporation into wet deposition is therefore of considerable interest for environmental research. The project “Winter precipitation at Mount Rigi” addresses the processes determining the chemical composition of wet deposition through an integrated approach considering atmospheric physical and chemical processes and their complex interactions. The investigated topics include: aerosol and gas scavenging, atmospheric chemistry (cloud water chemistry), cloud physics and dynamics. The design of the experiment, using three ground based measuring stations at the northwestern slope of the mountain, and the conceptual ideas using case study investigations are discussed.     

Both dioscorin,the tuber storage protein of yam (Dioscorea alata cv. Tainong No. 1), and its peptic hydrolysates exhibited angiotensin converting enzyme inhibitory activities

Dioscorin, the tuber storage protein of yam (Dioscorea alata cv. Tainong No. 1), was purified to homogeneity by DE-52 ion-exchange chromatography. This purified dioscorin was shown by spectrophotometric methods to inhibit angiotensin converting enzyme (ACE) in a dose-dependent manner (12.5-750 microg, respectively, 20.83-62.5% inhibitions) using N-[3-(2-furyl)acryloyl]-Phe-Gly-Gly (FAPGG) as substrates. The 50% inhibition (IC(50)) of ACE activity was 6.404 microM dioscorin (250 microg corresponding to 7.81 nmol) compared to that of 0.00781 microM (0.0095 nmol) for captopril. The commercial bovine serum albumin and casein (bovine milk) showed less ACE inhibitory activity. The use of qualitative TLC also showed dioscorin as ACE inhibitors. Dioscorin showed mixed noncompetitive inhibitions against ACE; when 31.25 microg of dioscorin (0.8 microM) was added, the apparent inhibition constant (K(i)) was 2.738 microM. Pepsin was used for dioscorin hydrolysis at 37 degrees C for different times. It was found that the ACE inhibitory activity was increased from 51.32% to about 75% during 32 h hydrolysis. The smaller peptides were increased with increasing pepsin hydrolytic times. Dioscorin and its hydrolysates might be a potential for hypertension control when people consume yam tuber.     

高产水稻土结构特性的初步研究

随着稻、麦的持续高产,高产稳产水稻土的土壤条件日益受到重视,不少单位进行了专门研究(上海市农业科学院土肥植保研究所土壤组,1975;广东省农业科学院土肥所土壤组,1976;中国科学院南京土壤研究所苏南调查组,1977).但研究的内容多偏重于土壤的农业化学性状或土壤形态的描述,而较少进行土壤结构性的研究.