为害小麦新害虫——显脉污灯蛾Spilarctia bisecta Leech (Lepidoptera: Arctiidae)

小麦是我国三大粮食作物之一, 其在生产过程中受到多种害虫为害;在调查重庆市潼南区小麦病虫害过程中新发现一种鳞翅目害虫为害小麦, 对其进行形态学及细胞色素氧化酶Ⅰ亚基(cytochrome oxidase Ⅰ, COⅠ)基因序列鉴定, 确定其为显脉污灯蛾Spilarctia bisecta Leech。污灯蛾属中有多种为害农作物的害虫, 但显脉污灯蛾在中国还未有为害小麦的确切报道, 这一发现提醒我们应当注意小麦和其他禾本科作物上的潜在害虫。     

A new alpha-methylene gamma-lactone sesquiterpene from Hedyosmum arborescens

A new sesquiterpene lactone, 7alpha,10alpha-epoxy-1alpha(H),5alpha(H)-guaia-3,11(13)-dien-8alpha,12-olide, was isolated from the leaves of Hedyosmum arborescens. The structure of this unusual 7,10-epoxy-guaianolide was determined by spectroscopic methods, particularly one- and two-dimensional 1H and 13C NMR.     

A new Delta7,22 sterol from the bulbs of Autonoë madeirensis

The spectral data of a new Δ^7,22 sterol, 24S-ethyl-5α-cholesta-7,22E-dien-3α-ol β-galactopyranoside, isolated from the bulbs of Autonoë madeirensis, are reported.     

Lignin fragments rich in detached side-chain structures found in water-soluble LCC

The content of the glyceraldehyde-2-aryl ether-type structure in water-soluble lignin–carbohydrate complex (LCC) fractions, which were obtained from Japanese cedar and birch residual wood meal after milled wood lignin isolation, was determined by ozonation. Quite high amounts of the glyceraldehyde-2-aryl ether-type structure were found in water-soluble LCC fractions of both species; about 3–5 times higher than those of other fractions. This result, as well as the high content of the β-1 structure in these fractions shown in our previous reports, suggest that lignin in these fractions has the characteristics of endwise-type lignin, because the glyceraldehyde-2-aryl ether-type structure and β-1 structure are typical characteristics of this type of lignin fraction. These results are in good agreement with the generally accepted hypothesis that the glyceraldehyde-2-aryl ether-type structure and β-1 structure are generated at the same time by a radical coupling reaction. The results also indicated that these two structures are present in close proximity in the lignin.     

构造柱施工质量的几项控制措施的一点体会

本文作者介绍了构造柱的设置、施工程序等 ,并且对其施工质量常出现的问题提出了几项控制措施。     

Time course of the incidence/multiplicity and histopathological features of murine colonic dysplasia,adenoma and adenocarcinoma induced by benzo[a]pyrene and dextran sulfate sodium

Benzo[a]pyrene (BP) is mutagenic but noncarcinogenic in the murine colon. Recently, we reported rapid induction of colonic tumors by treatment of CD2F₁ mice with BP (125 mg/kg for 5 days) followed by a colitis inducer, dextran sulfate sodium (DSS) (4% in drinking water for 1 or 2 weeks). However, there are no reports on detailed time course and histopathological features of colonic proliferative lesions in this model. Here, we show the detailed time course of colonic dysplasia, adenoma and adenocarcinoma induced by treatment with BP, DSS, and a combination of the two (BP/DSS). In the colon of mice exposed to BP/DSS, 14.6 dysplastic foci per mouse were present one week after DSS treatment (week 4). The number of dysplastic foci decreased with time to 3.1 at week 9 and thereafter remained almost constant. At week 4, 1.5 adenocarcinomas were also observed, with a marked increase in numbers with time, reaching 29.3 at week 14. In contrast, the number of dysplastic foci induced by DSS alone showed a time course similar to that following BP/DSS treatment; however, only a few tumors appeared. Neither dysplastic foci nor neoplastic lesions were induced by BP only. In mice exposed to BP/DSS, β-catenin was demonstrated immunohistochemically in the nucleus and/or cytoplasm of the tumor cells, and this translocation from the cell membrane was evident in subsets of dysplastic foci. In dysplastic foci induced by DSS alone, β-catenin was absent in the nucleus/cytoplasm. These finding suggest that aberrant β-catenin accumulation in dysplastic foci is associated with tumor progression in this BP/DSS model.     

Plasma fluctuation in estradiol-17β and bone resorption markers around parturition in dairy cows

Blood samples were obtained sequentially from 10 dairy cows around the time of parturition to assess plasma fluctuations in estradiol-17β (E₂) levels in association with those of several bone resorption markers. Plasma E₂ concentration increased sharply a few days prepartum and decreased quickly after parturition. In terms of bone resorption markers, the plasma level of tartrate-resistant acid phosphatase isoform 5b (TRAP5b) rose significantly, commencing 1 week prepartum, and was maintained at this level to a few days postpartum. The plasma concentration of carboxyterminal collagen cross-links of type-I collagen (CTx) increased significantly after parturition. These observations suggest that osteoclast-mediated bone resorption was activated after parturition when plasma E₂ concentrations decreased.     

Downregulation of the expression of inhibin α subunit and betaglycan in porcine cystic follicles

Inhibins, as members of the transforming growth factor beta (TGF-β) superfamily, downregulate the synthesis and secretion of follicle-stimulating hormone (FSH) in an endocrine manner. The role of inhibin/betaglycan in the ovary regulation recently gained attention. To date, no data exist on the function of inhibin α subunit and betaglycan in cystic follicles. In this study, the expressions of inhibin α subunit and betaglycan in cystic follicles were investigated using immunohistochemistry, real-time PCR and Western blot analysis. Both inhibin α subunit and betaglycan immunoreactivities were mainly localized in the granulosa cells of follicles. Expression of inhibin α subunit and betaglycan was inferior in cystic follicles compared with that in normal large follicles. However, the result of enzyme-linked immunosorbent assay showed no significant difference in the decreasing in concentration of inhibin α subunit in cystic follicular fluid compared with the control (P>0.05). In this study, we explored the effects of FSH on betaglycan expression in granulosa cells in vitro. As expected, a significant increase in the expressions of betaglycan mRNA and protein in granulosa cells was observed in response to exogenous FSH (30 ng/ml) (P<0.05) compared with the control. Consequently, this study provides evidence that the expressions of inhibin α subunit and betaglycan are inferior in cystic follicles, and this may be caused by the decrease in FSH in the presence of a cystic follicle.     

Effect of Megasphaera elsdenii NCIMB 41125 dosing on rumen development,volatile fatty acid production and blood β‐hydroxybutyrate in neonatal dairy calves

Thirty calves were randomly assigned to two treatments and fed until weaning [42 days (d) of age]. Treatments were a control group (n = 15), which did not receive Megasphaera elsdenii (Me0) and a M. elsdenii group, which received a 50‐ml oral dose of M. elsdenii NCIMB 41125 (10⁸ CFU/ml) at day 14 day of age (Me14). Calves were given colostrum for the first 3 day followed by limited whole milk feeding. A commercial calf starter was offered ad libitum starting at day 4 until the end of the study. Fresh water was available throughout the study. Feed intake and growth were measured. Blood samples were collected via jugular venipuncture to determine β‐hydroxybutyrate (BHBA) concentrations. Fourteen male calves (seven per group) were euthanised on day 42 and digestive tracts harvested. Reticulo‐rumen weight was determined and rumen tissue samples collected from the cranial and caudal sacs of the ventral and dorsal portions of the rumen for measurements of papillae length, papillae width and rumen wall thickness. Dosing with M. elsdenii NCIMB 41125 improved starter dry matter intake (DMI), weaning body weight (BW) and tended to improve average daily gain. Calves in Me14 group had greater plasma BHBA concentration than Me0‐calves during the last 3 weeks of the trial and had at day 42 greater reticulo‐rumen weight, papillae width and papillae density compared to Me0. No differences in rumen wall thickness or papillae length were observed between the two groups. Total volatile fatty acids, acetate and propionate production did not differ between treatments, but butyrate production was greater in Me14 than Me0. Dosing M. elsdenii NCIMB 41125 showed benefit for calves with improved feed intake and rumen development suggesting increased epithelium metabolism and improved absorption of digestive end products.