Larvicidal and adulticidal activity of alkylphthalide derivatives from rhizome of Cnidium officinale against Drosophila melanogaster

The insecticidal activity of the chloroform extract of Cnidium officinale rhizomes and its constituents was investigated against larvae and adults of Drosophila melanogaster and compared with that of rotenone. Bioassay-guided isolation of the chloroform extract of C. officinale resulted in the isolation and characterization of four alkylphthalides, cnidilide (1), (Z)-ligustilide (2), (3S)-butylphthalide (3), and neocnidilide (4). The structures of these compounds were established by spectroscopic analysis. The isolated compounds 2, 3, and 4 exhibited LC50 values of 2.54, 4.99, and 9.90 micromol/mL of diet concentration against larvae of D. melanogaster, respectively. Against both sexes (males/females, 1:1) of adults (5-7 days old), compound 3 showed the most potent activity of the compounds isolated with the LD50 value of 5.93 microg/adult, comparable to that of rotenone (LD50 = 3.68 microg/adult). Structure-activity relationships of phthalides isolated suggest that the presence of conjugation with the carbonyl group in the lactone ring appeared to play an important role in the larvicidal activity. Acetylcholinesterase (prepared from the adult heads of D. melanogaster) inhibitory activity was also investigated in vitro to determine the insecticide mode of action for the acute adulticidal activity.     

Inhibitory effects of citrus essential oils and their components on the formation of N-nitrosodimethylamine

Twenty-eight kinds of citrus essential oils and their components were studied for inhibitory effects on the formation of N-nitrosodimethylamine (NDMA). The reaction mixture consisted of dimethylamine and sodium nitrite adjusted at pH 3.6, in addition to essential oils and an emulsifying agent. The quantification was determined by high-performance liquid chromatography monitored at 220 nm. All of the essential oils inhibited the formation of NDMA in the range of 20-85%. The oils of ujukitsu (Citrus ujukitsu Hort. ex Shirai), yuzu (C. junos Tanaka), mochiyu (C. inflata Hort. ex Tanaka), and ponkan (C. reticulata Blanco cv. F-2426) inhibited the formation of NDMA much more effectively than other citrus oils. The inhibitory proportions of components of citrus essential oils such as myrcene, alpha-terpinene, and terpinolene were as high as 80%.     

A Growth Performance and Nonlinear Growth Curve Functions of Large- and Normal-Sized Japanese Quail (Coturnix japonica)

This study aimed to evaluate the differences between the growth patterns of large- and normal-sized Japanese quail strains and their F₁ progeny, by fitting their growth parameter values to five nonlinear regression growth models (Weibull, Logistic, Gompertz, Richards, and Brody). The Richards model presented the best fit for both sexes of the large-sized quail strain, whereas the Gompertz model presented the best fit for both sexes of the normal-sized quail strain, based on goodness-of-fit criteria (higher adjusted R² and lower Akaike and Bayesian information criteria). Both sexes of F₁ birds derived from the cross between normal-sized females and large-sized males were best fitted by the Richards model. In contrast, growth parameters of the F₁ birds derived from the cross between large-sized females and normal-sized males were best fitted to the Gompertz model. The data could be fitted nearly as well to the Weibull and Logistic models as to the Richards and Gompertz models. The Brody model presented the poorest fit for the growth parameter values. The results indicated that the Richards and Gompertz models could best describe the growth characteristics of both large- and normal-sized quails. Moreover, the observed growth pattern of the F₁ birds was likely inherited from the male parental strain. To the best of our knowledge, this is the first study comparing the growth curves of the reciprocal F₁ generations with their parental strains in quails.     

The enhancement of Th1 immune response by anti-PD-L1 antibody in cattle infected with Mycobacterium avium subsp. paratuberculosis

Johne’s disease, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic enteritis of ruminants. Previous studies have shown that programmed death-ligand 1 (PD-L1) is associated with the disease progression, and PD-L1 blockade activates MAP-specific Th1 responses in vitro. Here, we performed anti-PD-L1 antibody administration using 2 MAP-infected cattle at the late subclinical stage of infection. After administration, bacterial shedding was reduced or maintained at a low level. Additionally, MAP-specific Th1 cytokine production was upregulated, and CD69 expression was increased in T cells. Collectively, the treatment has a potential as a novel control method against Johne’s disease.     

Estimation of Zinc and Copper Balance in Japanese Farmland Soil Associated with the Application of Chemical Fertilizers and Livestock Excreta

We estimated the zinc (Zn) and copper (Cu) balance in Japanese farmland soil in 1997. Zinc and Cu uptake by crops amounted to 563 Mg and 108 Mg, respectively, while Zn and Cu doses from chemical fertilizer were 297 Mg and 63 Mg, respectively. Zinc and Cu contents of livestock excreta were estimated to be 2,863 Mg and 713 Mg, and 1,551 Mg and 337 Mg of this was applied to farmland soil. As a result, there was an excess of 1,285 Mg of Zn and 292 Mg of Cu in farmland soil. This excess corresponded to 0.379% of the amount of total Zn and 0.270% of the amount of total Cu in farmland soil. Even if all excess Zn and Cu was accumulated in farmland soil, it would take more than 190 years to reach the permissible upper level of Zn, based on the average Zn concentration in non-polluted farmland soil. However, the promotion of the use of livestock excreta, especially pig excreta that contain high levels of Zn and Cu, may shorten the time required to reach the level. Although there are some guidelines, the recommended dose level has not clearly determined. Conventional dose of Zn applied through chemical fertilizer and manure is lower than the recommended Zn application level. Doses may depend on plant diagnosis and we should monitor the contamination of soils and crops with Zn and Cu, or the application might depend on other indicators like the Zn/cadmium ratio.     

Statistical interferometric investigation of nano-scale root growth: effects of short-term ozone exposure on ectomycorrhizal pine (<Emphasis Type="Italic">Pinus densiflora</Emphasis>) seedlings

This study presents the effects of short-term ozone exposure on the nano-scale growth behavior of the fine roots of Pinus densiflora (Japanese red pine) seedlings. Root elongation measurements were obtained in nanometers for very short (sub-second) time intervals by using the optical interference method called statistical interferometry, developed by the authors. Three categories of P. densiflora seedlings were investigated; two categories were infected with ectomycorrhiza of Pisolithus sp. (Ps) and Cenococcum geophilum (Cg), while the third was without any fungal infection. In experiments, two points on a root with a separation of 3 mm were illuminated by laser beams and the elongation was measured continuously by analyzing speckle patterns successively taken by a CCD camera. The ectomycorrhizal fungi-infected and uninfected seedlings were exposed to ozone at concentrations of 120 and 240 ppb for periods of 1, 3, or 5 h in separate treatments. The root elongations of P. densiflora seedlings were measured before and immediately after the each ozone treatment and then the root elongation rates (RER) were determined for growth-measurement periods of 5.5 s and 9.5 min. From the measurements obtained for 9.5 min, we found that the RERs of uninfected and Cg-infected seedlings were reduced by 42 and 18%, respectively, after 5 h of exposure to 120 ppb ozone compared with that before exposure, while the reduction in RER of Ps-infected seedlings was not significant. When the concentration of ozone was increased to 240 ppb, the RERs of Ps-infected and Cg-infected seedlings were reduced by 32 and 44%, respectively, after exposure for 5 h, while the reduction in RER of uninfected seedlings was 59%. These observations prove that the non-mycorrhizal seedling roots are more sensitive to ozone stress. From this study, we found that the RERs of both mycorrhizal and non-mycorrhizal seedlings apparently fluctuated throughout the measurements, even within a few minutes.     

Gigantic photoresponse in 1/4-filled-band organic salt (EDO-TTF)2PF6

We report that the organic salt (EDO-TTF)2PF6 with 3/4-filled-band (1/4-filled in terms of holes), which forms an organic metal with strong electron and lattice correlation, shows a highly sensitive response to photoexcitation. An ultrafast, photoinduced phase transition from the insulator phase to the metal phase can be induced with very weak excitation intensity at near room temperature. This response makes the material attractive for applications in switching devices with room-temperature operation. The observed photo-induced spectroscopic change shows that this photoinduced phase transition process is caused by the cooperative melting of charge ordering assisted by coherent phonon generation.     

Human hypertension caused by mutations in WNK kinases

Hypertension is a major public health problem of largely unknown cause. Here, we identify two genes causing pseudohypoaldosteronism type II, a Mendelian trait featuring hypertension, increased renal salt reabsorption, and impaired K+ and H+ excretion. Both genes encode members of the WNK family of serine-threonine kinases. Disease-causing mutations in WNK1 are large intronic deletions that increase WNK1 expression. The mutations in WNK4 are missense, which cluster in a short, highly conserved segment of the encoded protein. Both proteins localize to the distal nephron, a kidney segment involved in salt, K+, and pH homeostasis. WNK1 is cytoplasmic, whereas WNK4 localizes to tight junctions. The WNK kinases and their associated signaling pathway(s) may offer new targets for the development of antihypertensive drugs.