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1.
Over the past 25 years, new techniques, new discoveries, and new ideas have profoundly impacted our understanding of deuterostome interrelationships and, ultimately, deuterostome evolution. During the late 1980s and early 1990s morphological cladistic analyses made predictions about both taxonomic history and homology, predictions that would be tested independent of the morphological characters themselves with the advent of molecular systematics, the rise of evolutionary developmental biology, and continued exploration of the fossil record. Thanks to these three areas of inquiry, we have gone from scenarios where animals like mobile enteropneust hemichordates and chordates were derived from sessile filter-feeding animals like modern lophophorates, echinoderms, and pterobranch hemichordates, to a new perspective where hemichordates are recognized as the nearest living relative of the echinoderms, and that vagile gill-bearing animals like Cambrian vetulicolians are seen—at least by some—as close to the deuterostome last common ancestor, with both sessility and filter-feeding convergent features of deuterostomes (e.g., echinoderm) and non-deuterostomes (e.g., lophophorates) alike. Although much of the backbone of the new deuterostome phylogeny is supported by multiple independent data sets, as are statements of homology of several different morphological characters, in particular the homology of gill slits across Deuterostomia, nonetheless, the next quarter century of study on this remarkable group of animals promises to be as equally illuminating and exciting as the past quarter century.  相似文献   

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New neprilysin inhibitors containing an α-mercaptoketone HSC(R1R2)CO group, as zinc ligand were designed. Two parameters were explored for potency optimization: the size of the inhibitor which could interact with the S1, S1′ or S2′ domain of the enzyme and the nature of the substituents R1, R2 of the mercaptoketone group. Introduction of a cyclohexyl chain in R1, R2 position and a (3-thiophen)benzyl group in position R3 (compound 12n) yielded to the most potent inhibitor of this series with a Ki value of 2 ± 0.3 nM. This result suggests that this new inhibitor interacts within the S1, S1′ domain of NEP allowing a pentacoordination of the catalytic Zn2+ ion by the mercaptoketone moiety.  相似文献   

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The recent recognition of the earliest Andean Tithonian ammonite fauna (Picunleufuense Zone) has allowed a balanced classification of the ataxioceratid ammonites, reflecting their phylogenetic relationships. The Picunleufuense Zone fauna, first recognized in the Neuquén Basin at the base of the Vaca Muerta Formation, is represented by numerous records of sparse ammonite faunas from Antarctica, the Austral Basin and the Tarapacá Basin (N. Chile and S. Peru). These Southeastern Pacific faunas include the Tithonian genera Indansites, Choicensisphinctes, Zapalia, Krantziceras (Tithonian–lower Berriasian) and Platydiscus. These five genera are grouped in a new subfamily established in this paper: Zapaliinae subfam. nov. (type genus: Zapalia). The origin of Indansites and Choicensisphinctes (possibly via Indanistes) from Lithacoceras is discussed. Zapalia must have been originated from Indanistes in the upper Proximus Zone. Platydiscus could have been originated from Krantziceras. The Tithonian Southeastern Pacific ataxioceratids (Zapaliinae subfam. nov.) form a group well separated from the Tithonian Indo-Madagascan Virgatosphinctinae.  相似文献   

7.
Yin ZW  Li LZ  Zhao MJ 《ZooKeys》2012,(175):75-86
Two new species, Pselaphodes linae Yin & Li, sp. n. (Hainan, Fujian) and Pselaphodes shii Yin & Li, sp. n. (Hainan) are described from South China. Taiwanophodes minor Hlaváč is reported from outside Taiwan for the first time. Illustrations of major diagnostic features are provided for all treated taxa. The latest key to Chinese Pselaphodes is modified to include the new species.  相似文献   

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Some new α-aminomethylenephosphonic acids 111 were synthesised and characterised by 1H, 13C, 31P NMR, IR spectroscopy and elemental analysis. The potencies of these compounds to inhibit human erythrocyte acetylcholinesterase (hAChE, EC 3.1.1.7) were studied by a modified Ellman’s method. In addition, the log P values were computed by Hyperchem software. Here, alendronate was used as a reference inhibitor. Results showed that the IC50 values ranged from 9.11 to 28.72?mM. The half maximal inhibitory concentration (IC50) value decreased with an increasing number of carbon atoms of the amine group in compounds 15. Also, in most cases, increasing the number of carbon atoms led to enhancement of the toxicity as predicted by the log P values. Using Lineweaver-Burk and Dixon analysis, it was indicated that compounds 110 are mixed inhibitors while compound 11 is a coupling or uncompetitive inhibitor. The results showed that the electronic changes have ignorable effects, steric influence is important in some cases, but the lipophilicity parameter is the most significant factor in hAChE inhibition by bisphosphonates.  相似文献   

10.
Summary -d-N-acetylglucosaminidase staining characteristics of rosetted or non-rosetted normal and malignant lymphoid cells were compared with those observed after nonspecific esterase and acid phosphatase staining. With the three cytochemical techniques a similar staining pattern was observed in T cells (E-rosettes), their subpopulations T and T, B cells and the non-T, non-B cells, as well as in the T cell populations defined with the monoclonal antibodies OKT3,4 and 8. T cells mostly diplayed a dot-like reaction, T and the non-T, non-B cells a fine to heavy granular reaction, while most B cells were negative. OKT4 and OKT8 positive lymphocytes showed for the larger part a dot-like staining pattern, however, the frequency of cells with a granular pattern was distinctly higher in the OKT8, than in the OKT4 positive cells.E(+)mIg(–) and E(–)mIg(–) A.L.L. blasts stained either with a dot-like or granular pattern or failed to react when stained cytochemically for -d-N-acetylglucosaminidase, nonspecific esterase and acid phosphatase activity. Only in a few instances a discrepancy was observed between the types of staining for esterase and acid phosphatase on one hand and those for -d-N-acetylglucosaminidase on the other.  相似文献   

11.
1. Lasiohelea aeschrodenta, sp. nov Female Head with eyes bare, AR 2.09;maxillary palp with a sensory pore on segment 3. Buccal armature has about 10 teeth which separated irregulary in the cibarium;clypeus with about 16 setae. Wing about 0.86 mm. long, with bare areas along veins. TR 1.74 in hind leg, with narrow scales on each tarsus. Spermatheca round and small, with abroad basical pore. Holotype:♀ Dukou, Sichuan, 1979 X. 10-11; Paratypes: 2♀♀Sichuan,Xichang, 1979 X. 5.  相似文献   

12.
A series of aromatic disulfonamide (1-8) derivatives and 4-methylbenzenesulfonyl hydrazide (9) were synthesized and characterized. All compounds were evaluated in vitro for their antimicrobial activity against Staphylococcus aureus ATCC 25953, Bacillus cereus ATCC 6633, Bacillus magaterium RSKK 5117, Escherichia coli ATCC 11230, Salmonella enterititis ATCC 13076 by microdilution and disc diffusion methods. Antimicrobial activity of the aromatic disulfonamides decreased as the length of the carbon chain increased. An analysis of the structure- activity relationship (SAR) along with computational studies showed that the most active compound (9) possessed low lipophilicity (AlogP=0.59) and high solubility (logS = -1.33).  相似文献   

13.
We revise the 10 genera and 23 species of the tribe Phaeogenini (Ichneumonidae: Ichneumoninae) known to occur in the Afrotropical region. We describe the following 13 new taxa: Kibalus Rousse, van Noort & Diller, gen. n.; K. toro Rousse, van Noort & Diller, sp. n.; K. mubfs Rousse & van Noort, sp. n.; Arearia oxymoron Rousse & van Noort, sp. n.; Chauvinia nyanga Rousse & van Noort, sp. n.; Dicaelotus asantesana Rousse & van Noort, sp. n.; D. hoerikwaggoensis Rousse & van Noort, sp. n.; D. tablemountainensis Rousse & van Noort, sp. n.; Heterischnus mfongosi Rousse & van Noort, sp. n.; H. mkomazi Rousse & van Noort, sp. n.; Lusius flummox Rousse & van Noort, sp. n.; Tycherus amatola Rousse & van Noort, sp. n.; and T. nardousberg Rousse & van Noort, sp. n. New distribution records: Heterischnus africanus (Heinrich, 1936) from South Africa, Tanzania and Uganda; H. krausi Schönitzer, 1999 from Rwanda; Lusius tenuissimus (Heinrich, 1938) from Democratic Republic of Congo, Malawi, Nigeria, South Africa, and Zimbabwe. A doubtful record of Aethecerus foveolatus Gregor, 1940 from Sao Tome is additionaly reported in the appendix. We provide illustrated diagnoses and identification notes. Online interactive dichotomous and matrix Lucid keys to genera and species are available at http://www.waspweb.org.  相似文献   

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The male of Brumptomyia angelae, sp. nov., a new species of Phlebotominae (Diptera, Psychodidae) of the Atlantic forest of the state of Paraná, Brazil, is described and illustrated. This new taxon is closely related to Brumptomyia ortizi Martins, Silva & Falc?o 1971, Brumptomyia nitzulescui (Costa Lima, 1932), and Brumptomyia troglodytes (Lutz, 1922). The male genitalia of these three latter species have also been drawn.  相似文献   

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In transmissible spongiform encephalopathies (TSEs) and Alzheimer disease (AD) both misfolding and aggregation of specific proteins represent key features. Recently, it was observed that PrPC is a mediator of a synaptic dysfunction induced by Aβ oligomers. We tested a novel γ-secretase modulator (CHF5074) in a murine model of prion disease. Groups of female mice were intracerebrally or intraperitoneally infected with the mouse-adapted Rocky Mountain Laboratory prions. Two weeks prior infection, the animals were provided with a CHF5074-medicated diet (375 ppm) or a standard diet (vehicle) until they showed neurological signs and eventually died. In intracerebrally infected mice, oral administration of CHF5074 did not prolong survival of the animals. In intraperitoneally-infected mice, CHF5074-treated animals showed a median survival time of 21 d longer than vehicle-treated mice (p < 0.001). In these animals, immunohistochemistry analyses showed that deposition of PrPSc in the cerebellum, hippocampus and parietal cortex in CHF5074-treated mice was significantly lower than in vehicle-treated animals. Immunostaining of glial fibrillary acidic protein (GFAP) in parietal cortex revealed a significantly higher reactive gliosis in CHF5074-treated mice compared with the control group of infected animals. Although the mechanism underlying the beneficial effects of CHF5074 in this murine model of human prion disease is unclear, it could be hypothesized that the drug counteracts PrPSc toxicity through astrocyte-mediated neuroprotection. CHF5074 shows a pharmacological potential in murine models of both AD and TSEs thus suggesting a link between these degenerative pathologies.Key words: TSE, prion, murine model, γ-secretase modulator, therapy  相似文献   

17.
γ1- and γ2-zeathionins (γ1-Z and γ2-Z) are members of a family of small and basic peptides involved in plant protection. These plant defensins exhibit remarkable structural similarity to scorpion neurotoxins and insect defensins. In the present report, we used the whole-cell patch clamp technique to investigate the inhibition of the sodium current (INa) by γ1-Z and γ2-Z in the GH3 cell line. Both γ1-Z and γ2-Z rapidly and reversibly inhibited INa without changing the kinetics or voltage dependence of activation or inactivation. To our knowledge, this is the first example of a plant protein that inhibits the sodium channel. From structural comparisons with the μ-conotoxins, a family of peptides that block the sodium channel, we detected some similar features that could provide the basis of inhibition of sodium channels by γ-zeathionins.  相似文献   

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This report discribes 2 new species of Haematopota, 1 new species of Tabanus and 2 males of T. omeishanensis Xu, and T. liangshanensis Xu. All the types are deposited in the Institute of Microbiology & Epidemiology, Academy of Military Medical Sciences, P.L.A., China. Haematopota erlangshanensis, sp. nov. (fig. 1; 2—2) This species is related to H. hakusanensis Togashi, but is easily  相似文献   

20.
The nuclear protein HMGB1, a new kind of chemokine?   总被引:5,自引:0,他引:5  
The chromosomal protein HMGB1 is now regarded as a proinflammatory cytokine. Importantly, HMGB1 has chemotactic activity suggesting its involvement in the early and late events of the inflammatory reaction. Therefore, HMGB1 has all the hallmarks of a chemokine (chemotactic cytokine). We propose to classify HMGB1 into a new group of proteins unrelated structurally to chemokines but having chemokine-like functions, and to name this class CLF (chemokine-like functions). The CLF class should include other unrelated molecules such as urokinase and its receptor, cytokines macrophage migration inhibitory factor (MIF) and interleukin (IL)-6, anaphylatoxin C5a, ribosomal protein S19, and thioredoxin that have similar chemokine-like activities. This innovative concept may lead to the identification of new therapeutic targets.  相似文献   

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