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101.
Scydmaenine beetles are commonly described as predators specialized in capturing and feeding on armored mites of the order Oribatida, and documented cases of feeding on other live arthropods have not been known. Based on laboratory observations and a broad choice of Acari (armored and soft‐bodied) and other soil arthropods, food preferences and associated behavior of two scydmaenine species are clarified and described. Adults of Scydmaenus tarsatus ignored oribatid and mesostigmatan mites, but readily attacked and fed on a soft‐bodied Rhizoglyphus sp. (Acaridae), and on small springtails, especially on Ceratophysella denticulata (Hypogastruridae). A water drinking behavior was observed for this species, not reported previously in any Staphylinidae. Scydmaenus hellwigii ignored all tested Acari (including Rhizoglyphus) and scavenged on dead neanurine collembolans or freshly cut pieces of large springtails; a long term culture was maintained by feeding beetles with isotomid springtails. Previously reported strict specialization of Scydmaenus as a predator on Oribatida was not confirmed and it is concluded that the studied species feed on live soft‐bodied organisms and scavenge on dead arthropods.  相似文献   
102.
C V Dang  E M Tan  J A Traugh 《FASEB journal》1988,2(8):2376-2379
Spontaneously occurring autoantibody to threonyl-tRNA synthetase found in the serum of patients with polymyositis and experimentally induced antibody against highly purified rabbit reticulocyte threonyl-tRNA synthetase were used to analyze the epitopes of threonyl-tRNA synthetase. The PL-7 autoantibody reacted with the native but not the denatured form of threonyl-tRNA synthetase, whereas the experimentally induced antibody recognized both the native and denatured forms of the enzyme. In addition, the PL-7 autoantibody specifically inhibited threonyl-tRNA synthetase activity whereas the experimentally induced antibody had no effect on aminoacylation. Thus, the epitopes recognized by the PL-7 autoantibody are formed by the tertiary structure of the enzyme and are associated with the catalytic site of the synthetase whereas the experimentally induced antibody recognizes epitopes formed by primary sequences not related to the catalytic function of the synthetase.  相似文献   
103.
Neotropical genera of Cephenniini characterized by an additional leg ‘segment’ (‘trochantellus’) are revised, and the following new taxa are described: Shyri gen.n. , Shyri pichincha sp.n. (type species of Shyri) (Ecuador), Shyri perversus sp.n. (Ecuador), Shyri quitu sp.n. (Ecuador), Shyri microphthalmus sp.n. (Ecuador), Monstrophennium gen.n. (type species: Cephennium spinicolle Schaufuss), Furcodes gen.n. , Furcodes apicalis sp.n. (type species of Furcodes) (Mexico), Furcodes tutule sp.n. (Honduras), Paracephennium pumilio sp.n. (Costa Rica), Pseudocephennium iwokramanum sp.n. (Guyana), Pseudocephennium trilineatum sp.n. (Guyana), Pseudocephennium araguanum sp.n. (Venezuela), Pseudocephennium maximum sp.n. (Venezuela), Pseudocephennium peruvianum sp.n. (Peru), Pseudocephennium cochabambanum sp.n. (Bolivia), Pseudocephennium saramaccanum sp.n. (Suriname) and Pseudocephennium brokopondonum sp.n. (Suriname). Pseudocephennium spinicolle (Schaufuss) is transferred to Monstrophennium. Cladistic analysis of characters from adult morphology of all genera of Cephenniini and a large outgroup sample from Cyrtoscydmini, Eutheiini, Scydmaenini, Clidicini and Mastigini strongly supported the monophyly of Cephenniini. However, only the Cephennomicrus group comprising nine genera was strongly supported as a monophyletic clade, while only weak support was found for the previously suggested Cephennodes group and Cephennium group. Two alternative hypotheses concerning the phylogeny of Cephenniini are put forward and discussed: (i) the Cephennium group is sister to all remaining Cephenniini; or (ii) the Cephennomicrus group is sister to all remaining Cephenniini. The Neotropical genera with ‘trochantellus’ form a well‐supported clade derived from the ancestral lineage of the Cephennodes group.  相似文献   
104.
Inhibition of casein kinase II by heparin   总被引:24,自引:0,他引:24  
Casein kinase II, a cyclic nucleotide-independent protein kinase from rabbit reticulocytes, was shown to be inhibited by heparin. Heparin specifically inhibited the enzyme and had no effect on other protein kinases, including casein kinase I, the type I and II cAMP-dependent protein kinases, protease-activated kinase I, and the hemin-controlled repressor. Heparan sulfate was found to be 40-fold less effective than heparin towards casein kinase II; other acid mucopolysaccharides had little or no effect on the enzymatic activity. Steady state studies revealed that heparin acted as a competitive inhibitor with respect to the substrate, casein. A value of 20 ng/ml or about 1.4 nM was obtained for the apparent Ki. The inhibition was not reversed by ATP and varying the ATP and heparin concentrations in the assay only altered the maximum velocity.  相似文献   
105.
Four initiation factors (eIF-2, -3, -4B, and -4F), previously shown to be phosphorylated in vivo, are each phosphorylated to a significant extent in vitro (greater than 0.3 mol of phosphate/mol of factor) by at least three different protein kinases. An S6 kinase from liver, an active form of protease-activated kinase II which modifies the same sites on S6 as those phosphorylated in vivo in response to mitogens, phosphorylates the beta subunit of eIF-2, eIF-3 (p120-p130), eIF-4B, and eIF-4F (p220). The Ca2+, phospholipid-dependent protein kinase phosphorylates eIF-2 beta, eIF-3 (p170, p120-p130), eIF-4B, and eIF-4F (p220, p25). The cAMP-dependent protein kinase significantly modifies eIF-4B and, to a lesser extent, eIF-3 (p130). Casein kinase I incorporates phosphate only into eIF-4B, but to a limited extent. Casein kinase II phosphorylates eIF-2 beta, eIF-3 (p170, p120), and eIF-4B, while protease-activated kinase I modifies eIF-3 (p170, p120-p130), eIF-4B, and eIF-4F (p220). The mitogen-stimulated S6 kinase from 3T3-L1 cells, activated in response to insulin, does not phosphorylate any of the initiation factors. There is no significant incorporation of phosphate into eIF-2 alpha or -gamma, eIF-4A, eIF-4C, eIF-4D, EF-1, or EF-2 by any of the protein kinases examined. Phosphopeptide mapping of tryptic digests of the phosphorylated subunits shows that the individual protein kinases modify different sites. The sites phosphorylated in vitro reflect those modified in vivo as shown with eIF-4F in concomitant studies with reticulocytes treated with tumor-promoting phorbol ester (Morley, S.J., and Traugh, J. A. J. Biol. Chem., in press). Thus, we have identified multipotential protein kinases which modify four initiation factors phosphorylated in vivo and have shown that phosphorylation of these translational components can be coordinately regulated.  相似文献   
106.
Hexazonium pararosaniline is a valuable reagent that has been used in enzyme activity histochemistry for 50 years. It is an aqueous solution containing the tris-diazonium ion derived from pararosaniline, an aminotriarylmethane dye, and it contains an excess of nitrous acid that was not consumed in the diazotization reaction. Other investigators have found that immersion for 2 min in an acidic (pH 3.5) 0.0015 M hexazonium pararosaniline solution can protect cryostat sections of unfixed animal tissues from the deleterious effects of aqueous reagents such as buffered solutions used in immunohistochemistry, while preserving specific affinities for antibodies. In the present investigation hexazonium pararosaniline protected lymphoid tissue and striated muscle against the damaging effects of water or saline. The same protection was conferred on unfixed sections treated with dilute nitrous or hydrochloric acid in concentrations similar to those in hexazonium pararosaniline solutions. Model tissues (solutions, gels or films containing gelatin and/or bovine albumin) responded predictably to well known cross-linking (formaldehyde) or coagulant (mercuric chloride) fixatives. Hexazonium pararosaniline solutions prevented the dissolution of protein gels in water only after 9 or more days of contact, during which time considerable swelling occurred. It is concluded that there is no evidence for a “fixative” action of hexazonium pararosaniline. The protective effect on frozen sections of unfixed tissue is attributable probably to the low pH of the solution.  相似文献   
107.
Objective: To identify factors influencing attitudes of partially dentate adults towards dental treatment in Ireland. Background: People are retaining more teeth later in life than ever before. Management of partially dentate older adults will be a major requirement for the future and it is important to determine factors which may influence patients’ attitudes to care. Methods: Subjects: A purposive sample of 22 partially dentate patients was recruited; 12 women and 12 men, ranging in age from 45 to 75 years. Data Collection: Semi‐structured individual interviews. Results: Dental patients have increasing expectations in relation to (i) a more sophisticated approach to the management of missing teeth and (ii) their right to actively participate in decision making regarding the management of their tooth loss. There is some evidence of a cohort effect with younger patients (45–64 years) having higher expectations. Conclusions: The evidence of a cohort effect within this study in relation to higher patient expectations indicates that both contemporary and future patients are likely to seek a service based on conservation and restoration of missing teeth by fixed prostheses.  相似文献   
108.
Persistent inflammation and associated excessive oxidative stress have been crucially implicated in quartz-induced pulmonary diseases, including fibrosis and cancer. We have investigated the significance of the particle surface reactivity of respirable quartz dust in relation to the in vivo generation of reactive oxygen and nitrogen species (ROS/RNS) and the associated induction of oxidative stress responses in the lung. Therefore, rats were intratracheally instilled with 2 mg quartz (DQ12) or quartz whose surface was modified by either polyvinylpyridine-N-oxide (PVNO) or aluminium lactate (AL). Seven days after instillation, the bronchoalveolar lavage fluid (BALF) was analysed for markers of inflammation (total/differential cell counts), levels of pulmonary oxidants (H2O2, nitrite), antioxidant status (trolox equivalent antioxidant capacity), as well as for markers of lung tissue damage, e.g. total protein, lactate dehydrogenase and alkaline phosphatase. Lung homogenates as well as sections were investigated regarding the induction of the oxidative DNA-lesion/oxidative stress marker 8-hydroxy-2''-deoxyguanosine (8-OHdG) using HPLC/ECD analysis and immunohistochemistry, respectively. Homogenates and sections were also investigated for the expression of the bifunctional apurinic/apyrimidinic endonuclease/redox factor-1 (APE/Ref-1) by Western blotting and immunohistochemistry. Significantly increased levels of H2O2 and nitrite were observed in rats treated with non-coated quartz, when compared to rats that were treated with either saline or the surface-modified quartz preparations. In the BALF, there was a strong correlation between the number of macrophages and ROS, as well as total cells and RNS. Although enhanced oxidant generation in non-coated DQ12-treated rats was paralleled with an increased total antioxidant capacity in the BALF, these animals also showed significantly enhanced lung tissue damage. Remarkably however, elevated ROS levels were not associated with an increase in 8-OHdG, whereas the lung tissue expression of APE/Ref-1 protein was clearly up-regulated. The present data provide further in vivo evidence for the crucial role of particle surface properties in quartz dust-induced ROS/RNS generation by recruited inflammatory phagocytes. Our results also demonstrate that quartz dust can fail to show steady-state enhanced oxidative DNA damage in the respiratory tract, in conditions were it elicits a marked and persistent inflammation with associated generation of ROS/RNS, and indicate that this may relate to compensatory induction of APE/Ref-1 mediated base excision repair.  相似文献   
109.
Leonardite is an oxidized form of lignite carbon, which is obtained from fossilized organic materials. Such materials are used for the extraction of humic acids (HA). The result of the addition of HA of organic origin on soil structure is known; however, the effects of adding HA of Leonardite on soil structure have been scarcely investigated. The objectives of this research were (1) to determine the influence of humic acids derived from Leonardite in increasing the aggregate stability of an Aridisol under greenhouse conditions, and (2) evaluate the morphology of the root xylem during the phenological development of melon plants (Cucumis melo L.). Three treatments of HA solution application to the soil were used: soil without solution application (HA0), and application of HA solution to the soil with pH 6 (HA6) or (HA7). Aggregate stability (As) and bulk density (Da) were evaluated as soil variables. Development and quantification of xylem area were studied on plants. There were significant differences in aggregate stability. Also, there was an increase in the root xylem area, and the best treatment was when AH7 solution was applied. Humic acids derived from Leonardite increased the stability of soil aggregates when plants grew under greenhouse conditions, and fostered the development of xylem conduits during the fruiting stage.  相似文献   
110.
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