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1.
As shown by chemical analysis and field trapping, the sex pheromone of Grapholita lobarzewskii consists of a blend of (E)-8-dodecenyl acetate and (Z)-8-dodecenyl acetate. Maximum attractiveness was found at 80–95%. Dodecyl acetate and tetradecyl acetate, both present in the female gland, did not affect trap catch. G. lobarzewskii has recently gained importance as a pest of apple and plum, but has so far been referred to as Grapholita janthinana. The latter is attracted to the same two compounds, but in reversed portions (20% E).
Zusammenfassung Chemische Analysen und Feldversuche zeigen, dass das Sexualpheromon des Kleinen Fruchtwicklers, G. lobarzewskii aus (E)-8-Dodecenylacetat (Z8-12:Ac) und (Z)-8-Dodecenylacetat (Z8-12:Ac) besteht. Die grösste Lockwirkung wurde mit einem Gemisch der beiden Substanzen bei einem E-Anteil von 80–95% erzielt. Dodecylacetat (12:Ac) und Tetradecylacetat (14:Ac) wurden ebenfalls in den weiblichen Pheromondrüsen nachgewiesen, hatten aber im Freiland keinen Einfluss auf die Lockwirkung. G. lobarzewskii tritt seit einiger Zeit in der Schweiz als Schädling von Apfel und Zwetschge auf und ist an ihrem charakteristischem Frassgang leicht erkennbar. Die Art wurde bisher irrtümlich als G. janthinana bezeichnet. G. janthinana lebt auf Rosaceen, und wird vom gleichen Substanzpaar angelockt, allerdings bei umgekehrtem Mischungsverhältnis (20% E).
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2.
Résumé La métamorphose des insectes est régie par un équilibre hormonal complexe dans lequel l'hormone juvénile (HJ) joue un rôle important. Au dernier stade larvaire, la teneur en HJ est particulièrement faible dans le corps de l'insecte. Si un régulateur de croissance d'insectes (RCI)-un mimétique de l'HJ-est appliqué à ce moment-là, la mue nymphale est pertubée provoquant des déformations morphogénétiques caractéristiques. La teneur en HJ est également très faible dans les ufs fraîchement pondus. Les traitements aux RCI peuvent par conséquent perturber le développement embryonnaire de certaines espèces et produire ainsi un effet ovicide. Depuis quelques années deux RCI-le fenoxycarb et le CGA 45 128-ont été testés pour leur activité morphogénétique sur le dernier stade larvaire de quelques ravageurs tels qu'Adoxophyes orana F.v.R., ainsi que pour leur activité ovicide sur les ufs frais de Cydia pomonella L. et Grapholita funebrana Tr. Après quelques années d'expérimentation et de commercialisation des RCI dans les vergers européens, il s'avère que l'utilisation de ces produits peu toxiques, sélectifs et peu nocifs pour la faune utile, constitue une amélioration considérable pour l'aménagement de la lutte intégrée.
Insect growth regulators (IGR), mimics of juvenile hormone, as morphological and ovicidal means of control against orchard tortricids
Summary Metamorphosis is regulated by a complex hormonal balance in which juvenile hormone (JH) plays an important part. At the last larval instar the content of JH is particularly low in the insect body. If an insect growth regulator (IGR) — a mimic of JH-is applied at this time, the pupal moult may be disturbed with the characteristic morphogenetical deformations. The JH content is also very low in freshly laid eggs. Therefore IGR treatments may disturb the embryonic development of some species and produce an ovicidal activity. During a few years two IGR-fenoxycarb and CGA 45128-were evaluated for their morphogenetical effect on the last larval instar of Adoxophyes orana F.v.R. and their ovicidal effect on freshly laid eggs of Cydia pomonella L. and Grapholita funebrana Tr. After a few years of experimentation with both compounds and of commercialisation of fenoxycarb in European orchards, IGR confirmed to present a considerable improvement in integrated pest management due to selectivity, and low mammal toxicity.
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3.
Galanin is a modulator of fast transmission in adult brain and recent evidence suggests that it also acts as a trophic factor during neurogenesis and neural injury and repair. Previous studies in our laboratory have identified galanin mRNA in Purkinje cells of adult and developing rat (but not adult mouse) cerebellum; and galanin-binding sites in adult mouse (but not rat) cerebellum. The post-natal development of the cerebellum provides a unique and convenient model for the investigation of developmental processes and to learn more about putative cerebellar galanin systems, the current study examined the presence and distribution of galanin-like-immunoreactivity (- LI), [(125)I]-galanin binding sites and galanin receptor-1 (GalR1) mRNA in post-natal mouse cerebellum. Using autoradiography and in situ hybridization, [(125)I]-galanin binding sites and GalR1 mRNA were first detected on post-natal day 10 (P10) in the external germinal layer of all lobes and high levels were maintained until P14. Quantitative real-time PCR assays detected GalR1 mRNA in whole cerebellum across the post-natal period, with a strong induction and peak of expression at P10. Assessment of galanin levels in whole cerebellum by radioimmunoassay revealed relatively similar concentrations from P5 to P20 and in adult mice (80-170 pg/mg protein), with a significantly higher concentration (250 pg/mg, p < 0.01) detected at P3. These concentrations were some four- to six-fold lower than those in adult forebrain samples. Using immunohistochemistry, galanin-like-immuno-reactivity was observed in prominent fibrous elements within the white matter tracts of the cerebellum at P3-5 and in more punctate elements in the internal granule cell layer and associated with the Purkinje cell layer at P12 and P20. Increased levels of GalR1 mRNA and galanin binding (attributed to GalR1) in the external granule cell layer at P10-12/(14) coincide with granule cell migration from the external to the inner granule cell layer and together with demonstrated effects of other neuropeptide-receptor systems suggest a role for GalR1 signalling in regulating this or related developmental processes.  相似文献   
4.
Tang TK  Wu MP  Chen ST  Hou MH  Hong MH  Pan FM  Yu HM  Chen JH  Yao CW  Wang AH 《Proteomics》2005,5(4):925-937
Severe acute respiratory syndrome (SARS) is a serious health threat and its early diagnosis is important for infection control and potential treatment of the disease. Diagnostic tools require rapid and accurate methods, of which a capture ELISA method may be useful. Toward this goal, we have prepared and characterized soluble full-length nucleocapsid proteins (N protein) from SARS and 229E human coronaviruses. N proteins form oligomers, mostly as dimers at low concentration. These two N proteins degrade rapidly upon storage and the major degraded N protein is the C-terminal fragment of amino acid (aa) 169-422. Taken together with other data, we suggest that N protein is a two-domain protein, with the N-terminal aa 50-150 as the RNA-binding domain and the C-terminal aa 169-422 as the dimerization domain. Polyclonal antibodies against the SARS N protein have been produced and the strong binding sites of the anti-nucleocapsid protein (NP) antibodies produced were mapped to aa 1-20, aa 150-170 and aa 390-410. These sites are generally consistent with those mapped by sera obtained from SARS patients. The SARS anti-NP antibody was able to clearly detect SARS virus grown in Vero E6 cells and did not cross-react with the NP from the human coronavirus 229E. We have predicted several antigenic sites (15-20 amino acids) of S, M and N proteins and produced antibodies against those peptides, some of which could be recognized by sera obtained from SARS patients. Antibodies against the NP peptides could detect the cognate N protein clearly. Further refinement of these antibodies, particularly large-scale production of monoclonal antibodies, could lead to the development of useful diagnostic kits for diseases associated with SARS and other human coronaviruses.  相似文献   
5.
Searching for virulence marking tests for Mycobacterium tuberculosis, Dubos and Middlebrook reported in 1948 that in an alkaline aqueous solution of neutral-red, the cells of the virulent H37Rv M. tuberculosis strain fixed the dye and became red in color, whereas the cells of the avirulent H37Ra M. tuberculosis strain remained unstained. In the 1950 and 1960s, fresh isolates of M. tuberculosis were tested for this neutral-red cytochemical reaction and it was reported that they were neutral-red positive, whereas other mycobacteria of diverse environmental origins that were non-pathogenic for guinea pigs were neutral-red negative. However, neutral-red has not really been proven to be a virulence marker. To test if virulence is in fact correlated to neutral-red, we studied a clinical isolate of M. tuberculosis that was originally neutral-red positive but, after more than 1 year passing through culture mediums, turned neutral-red negative. We found that, in comparison to the original neutral-red positive strain, this neutral-red negative variant was attenuated in two murine models of experimental tuberculosis. Lipid analysis showed that this neutral-red negative natural mutant lost the capacity to synthesize pthiocerol dimycocerosates, a cell wall methyl-branched lipid that has been related to virulence in M. tuberculosis. We also studied the neutral-red of different gene-targeted M. tuberculosis mutants unable to produce pthiocerol dimycocerosates or other cell wall methyl-branched lipids such as sulfolipids, and polyacyltrehaloses. We found a negative neutral-red reaction in mutants that were deficient in more than one type of methyl-branched lipids. We conclude that neutral-red is indeed a marker of virulence and it indicates important perturbations in the external surface of M. tuberculosis cells.  相似文献   
6.
Sinomenine, the main alkaloid extracted from the medicinal plant Sinomenium acutum, is known for its anti-inflammatory effects. Recent studies have suggested its anti-cancer effect in synovial sarcoma, lung cancer and hepatic cancer. However, the underlying molecular mechanism for its anti-cancer effect still remains unclear. This study investigated the anti-tumor activity of sinomenine hydrochloride (SH), a hydrochloride form of sinomenine, in human breast cancer cells in vitro and in vivo. We found that SH potently inhibited cell viability of a broad panel of breast cancer cell lines. Two representative breast cancer cell lines, namely ER(−)/PR(−) MDA-MB-231 and ER(+)/PR(+) MCF-7, were used for further investigation. The results showed that SH induced G1/S cell cycle arrest, caused apoptosis and induced ATM/Chk2- and ATR/Chk1-mediated DNA-damage response in MDA-MB-231 and MCF-7. The anti-cancer effect of SH was regulated by increased expression levels of p-ERK, p-JNK and p-38 MAPK. Further studies showed that SH resulted in an increase in reactive oxygen species (ROS) and inhibition of ROS by N-acetyl-L-cysteine (NAC) almost blocked SH-induced DNA damage but only mitigated SH-induced MAPK expression changes, suggesting that both ROS-dependent and -independent pathways were involved in MAPK-mediated SH-induced breast cancer cell death. The in vivo study demonstrated that SH effectively inhibited tumor growth without showing significant toxicity. In conclusion, SH induced breast cancer cell death through ROS-dependent and -independent pathways with an upregulation of MAPKs, indicating that SH may be a potential anti-tumor drug for breast cancer treatment.In recent decades, breast cancer is increasing in both developed and developing countries.1, 2, 3 Breast cancer has become the most common cancer and the leading cause of death in women all over the world.4 Although current strategies targeting breast cancer have improved markedly, breast cancer patients often develops metastasis5 and drug resistance.6 Therefore, it is necessary to search for new effective therapies for breast cancer treatment.Plants are one of the most important sources of compounds for chemoprevention and >60% of cancer therapeutics on the market or in preclinical trials are based on natural products.7, 8 The medicinal plant Sinomenium acutum Rehd. et Wils. (Fam. Menispermaceae) has been used to effectively treat rheumatoid arthritis for centuries in the Far East.9 Since its main effective component sinomenine (7,8-didehydro-4-hydroxy-3,7-dimethoxy-17-methylmorphinan-6-one, C19H23NO4, molecular weight: 329.38 Da, Figure 1a), a pure alkaloid, was extracted from the plant, numerous studies have been conducted on its underlying mechanisms for rheumatoid arthritis treatment10, 11 and other possible pharmacological effects, such as attenuation of ischemia/reperfusion injury,12, 13 treatment of neurodegenerative disorders14 and reduction of analgesic tolerance.15 Sinomenine hydrochloride (SH, Figure 1b), a hydrochloride chemical form of sinomenine, is widely used in clinical treatment of rheumatoid diseases for its anti-inflammatory and anti-immune effects.16 Recently, its anti-tumor activity has been found in synovial sarcoma, lung cancer and hepatic cancer;17, 18, 19 however, the molecular mechanisms and the signaling pathways of SH against cancer are still not clarified, and no studies have investigated whether SH could induce breast cancer cell death.Open in a separate windowFigure 1SH inhibited human breast cancer cell viability. Chemical structures of (a) sinomenine and (b) SH. (c) A panel of human breast cancer cell lines (MDA-MB-231, MCF-7, SK-BR-3, ZR-75-30, BT474 and T47D) were treated with SH (0, 0.1, 0.5 and 5.0 μmol/ml) for 48 h. Cell viability was measured by MTT assay. (d) Time-dependent inhibition of SH was evaluated by MTT assay. Data are represented as mean±S.D. of three independent experiments. *P <0.05, #P <0.01, SH-treated group compared with the untreated control group. (e) Cell colony formation was evaluated by clonogenic assay. (f) Morphology changes of breast cancer cells treated with SH. Representative data from three independent experiments are shownThere exist seven classes of mitogen-activated protein kinase (MAPK) intracellular signaling cascades, and four of them are implicated in breast diseases and function in mammary epithelial cells, including the extracellular-regulated kinase (ERK)1/2 pathway, the c-Jun N-terminal kinase (JNK) pathway, the p38 MAPK pathway and the ERK5 pathway.20 In this study, we especially focused on three prominent MAPK pathways, namely ERK1/2, JNK and p38. Milde-Langosch et al.21 have pointed out in a clinical study that high phosphorylated ERK proteins are good prognostic indicators in breast cancer. Sustained phosphorylation of p38 and JNK in breast cancer cells are also involved in anti-cancer treatment.22 Considering the important roles of MAPKs in breast cancer progression and cell proliferation, we hypothesized that SH inhibited breast cancer growth via modulation of MAPK pathways.In this study, we first demonstrated the anti-proliferative effect of SH on breast cancer cells in vitro and in vivo. We found that SH induced G1/S cell cycle arrest, caused cell apoptosis and triggered oxidative DNA damage in breast cancer cells. The results also demonstrated that SH induced breast cancer cell death by upregulating MAPK pathways and increasing intracellular reactive oxygen species (ROS) generation. The ROS scavenger N-acetyl-L-cysteine (NAC) almost blocked SH-induced DNA damage but only mitigated SH-induced MAPK expression changes, indicating that both ROS-dependent and -independent pathways were involved in the MAPK-mediated anti-cancer effect of SH.  相似文献   
7.
Abstract: Four populations of codling moth Cydia pomonella L. were collected as overwintering larvae from apple orchards with different pesticide pressure (S. Michele, Roncafort, Revò and Vervò) in the Trento province (northern Italy). Mortality rate caused by a predetermined discriminating concentration of tebufenozide topically applied on overwintering larvae was evaluated. Neonate F1 progeny of the same populations were assayed for susceptibility to tebufenozide by feeding them on thinning apples treated with an appropriate discriminating dose of the insecticide. The activities of the main enzyme systems involved in the detoxification of insecticides were also evaluated in each population and related to their susceptibility to tebufenozide. The topical test detected a significant loss in susceptibility to tebufenozide in two populations, S. Michele and Roncafort, while all the overwintering larvae collected in the orchards of Revò and Vervò died when treated topically with the discriminating concentration. The apple‐dipping test performed on the neonate larvae showed a highly significant reduction in the susceptibility of the two populations of S. Michele and Roncafort. A less significant reduction in mortality rate was found in the Revò population; however, no statistical difference was found between the Vervò population and the susceptible reference. None of the four field populations significantly differed from the susceptible strain for Glutathione‐S‐transferase and esterase activity. A significantly higher frequency of individuals of the S. Michele and Roncafort populations exhibited a higher mixed function oxidase activity than the susceptible strain. The small resistance ratio values found for the two populations together with the low frequency of individuals exibiting enhanced enzymatic activity, reveals that the selection process was still at the early stage. Because of its efficiency in early detection of resistance to tebufenozide, topical application on diapausing larvae can thus be considered an appropriate, simple and robust tool for implementing resistance monitoring programmes for tebufenozide.  相似文献   
8.
9.
To study the effect of hypercholesterolemia on vascular smooth muscle cell (VSMC) function, atherosclerosis-prone but plaque-free endothelium-denuded aortic rings (width 2mm) from C57Bl6 Wild Type (WT) and apolipoprotein E-deficient (apoE(-/-)) mice (age 4 months) were mounted in a myograph and loaded with Fura-2 AM to simultaneously measure free Ca(2+) ([Ca(2+)](i)) and force development. In comparison with WT, apoE(-/-) mice displayed higher basal [Ca(2+)](i). Moreover, the time constant of the second phase of the biphasic high K(+)-induced [Ca(2+)](i) response was significantly increased in apoE(-/-) compared to WT mice. This phase was abolished by treatment with cyclopiazonic acid (CPA), depleting sarcoplasmic reticulum (SR). Further investigation of SR dependent [Ca(2+)](i) handling with CPA and caffeine revealed no alteration of maximal SERCA or ryanodine receptor function. Inositol (1,4,5)-triphosphate receptor (IP(3)R)-mediated [Ca(2+)](i) release was, however, significantly increased in apoE(-/-) mice compared to WT mice as established with phenylephrine and ATP. In Ca(2+)-free conditions the ATP-induced [Ca(2+)](i) was not altered. The ATP-induced store-operated Ca(2+) entry was, however, significantly increased in apoE(-/-) compared to WT mice. The results demonstrate that basal [Ca(2+)](i) levels and IP(3)R-mediated store-operated [Ca(2+)](i) release over the plasma membrane were elevated in hypercholesterolemic but plaque-free apoE(-/-) mice.  相似文献   
10.
WW domain-containing oxidoreductase (WWOX), a putative tumour suppressor, is suggested to be involved in the hyperphosphorylation of Alzheimer's Tau. Tau is a microtubule-associated protein that has an important role in microtubule assembly and stability. Glycogen synthase kinase 3β (GSK3β) has a vital role in Tau hyperphosphorylation at its microtubule-binding domains. Hyperphosphorylated Tau has a low affinity for microtubules, thus disrupting microtubule stability. Bioinformatics analysis indicated that WWOX contains two potential GSK3β-binding FXXXLI/VXRLE motifs. Immunofluorescence, immunoprecipitation and molecular modelling showed that WWOX interacts physically with GSK3β. We demonstrated biochemically that WWOX can bind directly to GSK3β through its short-chain alcohol dehydrogenase/reductase domain. Moreover, the overexpression of WWOX inhibited GSK3β-stimulated S396 and S404 phosphorylation within the microtubule domains of Tau, indicating that WWOX is involved in regulating GSK3β activity in cells. WWOX repressed GSK3β activity, restored the microtubule assembly activity of Tau and promoted neurite outgrowth in SH-SY5Y cells. Conversely, RNAi-mediated knockdown of WWOX in retinoic acid (RA)-differentiated SH-SY5Y cells inhibited neurite outgrowth. These results suggest that WWOX is likely to be involved in regulating GSK3β activity, reducing the level of phosphorylated Tau, and subsequently promoting neurite outgrowth during neuron differentiation. In summary, our data reveal a novel mechanism by which WWOX promotes neuronal differentiation in response to RA.  相似文献   
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