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1.
Analyses of ITS sequences for 49 species of Olearia, including representatives from all currently recognised intergeneric sections, and 43 species from 23 other genera of Astereae,
rooted on eight sequences from Anthemideae, provide no support for the monophyly of this large and morphologically diverse
Australasian genus. Eighteen separate lineages of Olearia are recognised, including seven robust groups. Three of these groups and another eight species are placed within a primary
clade incorporating representatives of Achnophora, Aster, Brachyscome, Calotis, Camptacra, Erigeron, Felicia, Grangea, Kippistia, Lagenifera, Minuria, Oritrophium,
Peripleura, Podocoma, Remya, Solidago, Tetramolopium and Vittadinia. The remaining four groups and three individual species lie within a sister clade that also includes Celmisia, Chiliotrichum, Damnamenia, Pleurophyllum and Pachystegia. Relationships within each primary clade are poorly resolved. There is some congruence between this molecular estimate of
the phylogeny and the distribution of types of abaxial leaf-hair, which is the basis of the present sectional classification
of Olearia, but all states appear to have arisen more than once within the tribe. It is concluded that those species placed within the
second primary clade should be removed from the genus, but the extent to which species placed within the first primary clade
constitute a monophyletic group can only be resolved with further sequence data.
Received November 12, 2001; accepted April 29, 2002 Published online: November 22, 2002
Addresses of authors: Edward W. Cross, Centre for Plant Biodiversity Research, CSIRO, GPO Box 1600, Canberra, ACT 2601, Australia
(E-mail: ed.cross@csiro.au); Christopher J . Quinn, Royal Botanic Gardens, Mrs Macquaries Rd., Sydney, NSW 2000, Australia;
Steven J. Wagstaff, Landcare Research, PO Box 69, Lincoln 8152, New Zealand. 相似文献
2.
A. Gough S. Chapman K. Wagstaff P. Emery E. Elias 《BMJ (Clinical research ed.)》1996,312(7024):169-172
Monocycline is the most widely prescribed systemic antibiotic for acne largely because it needs to be given only once or twice a day and seems not to induce resistance. Up to April 1994 11 cases of minocycline induced systemic lupus erythematosus and 16 cases of hepatitis had been reported to the Committee on Safety of Medicines. An analysis of these cases together with seven other cases shows the severity of some of these reactions. Two patients died while taking the drug for acne and a further patient needed a liver transplant. Acne itself can induce arthritis and is often seen in association with autoimmine liver disease, but the clinical and biochemical resolution seen after withdrawal of the drug, despite deterioration of the acne, suggests a drug reaction. In five cases re-exposure led to recurrence. Because reactions may be severe early recognition is important to aid recovery and also to avoid invasive investigations and treatments such as corticosteroids and immunosuppresants. Safer alternatives should be considered for treating acne. 相似文献
3.
Chemical reaction of coenzyme M, sodium 2-mercaptoethanesulphonate (HS-CoM, Na+), and formaldehyde formed sodium 2-(hydroxymethylthio)ethanesulphonate (HOCH2-S-CoM), whereas reaction with the ammonium salt of HS-CoM yielded iminobis-[2-(methylthio)ethanesulphonate], monoammonium salt [NH = (CH2 - S - CoM)2]. In water, NH = (CH2 - S - CoM)2 decomposed to 2-(aminomethylthio)ethanesulphonate (NH2CH2 - S - CoM) and HOCH2-S-CoM. NH-2-CH2 - CoM was degraded further to form more HOCH2-S-CoM. The structures of these coenzyme M derivatives were confirmed by i.r. and n.m.r. spectroscopy and by elemental analysis. When added to cell extracts of Methanobacterium thermoautotrophicum, methane was formed from either HOCH2 - S - CoM or NH = (CH2 - S - CoM)2 at rates comparable with the rate of methane formation from the methanogenic precursor 2-(methylthio)-ethanesulphonate (CH3 - S - CoM). Formaldehyde was reduced to methane at similar rates. In addition, certain hemimercaptals, including thiazolidine and thiazolidine-4-carboxylate, were reduced, although at slower rates. The reduction of formaldehyde, thiazolidine, or thiazolidine-4-carboxylate required catalytic amounts of HS-CoM. ATP was required by cells extracts for reduction of each of these methane precursors. 相似文献
4.
Peptide YY (PYY) and ghrelin (GHR) may modulate one another's actions within the hypothalamus. Peripheral infusion of PYY in humans acutely suppresses circulating concentrations of GHR. Whether an association between PYY and GHR exists in the peripheral circulation of humans over 24 h is unknown. The purpose of this study was to determine if circulating concentrations of PYY and GHR were significantly associated over 24 h in humans. Participants (n = 13) were normal weight, moderately active, women ages 18–24 yr. Blood samples were obtained q10 min for 24 h and assayed using RIA for total PYY and total GHR hourly from 0800 to 1000 h and 2000 to 0800 h and q20 min from 1000 to 2000 h. Dietary intake during the 24 h procedure was comprised of 55% carbohydrates, 30% fat, and 15% protein (three meals and a snack). Statistical analyses included linear mixed-effects modeling to test whether PYY predicted GHR concentrations over 24 h. Participants weighed 57.0 ± 1.5 kg and had 26.1 ± 1.5% body fat (15.0 ± 1.1 kg), 42.1 ± 1.1 kg fat free mass, a BMI of 21.3 ± 0.5 kg/m2 and RMR of 1072 ± 28 kcal/24 h. Visually, PYY and GHR exhibited an inverse association over nearly the entire 24 h period. Statistically, circulating concentrations of 24 h PYY predicted 24 h GHR (ghrelin = 1860.51–2.14*PYY; p = 0.04). Circulating concentrations of PYY are inversely associated with GHR over 24 h. These data provide evidence that PYY may contribute to the modulation of the secretion of GHR in normal weight, premenopausal women over a 24 h period and supports similar inferences from experimental studies in animals and humans. 相似文献
5.
Pasquier CM; Promponas VI; Varvayannis NJ; Hamodrakas SJ 《Bioinformatics (Oxford, England)》1998,14(8):749-750
Summary : FT is a tool written in C++, which implements the Fourier
analysis method to locate periodicities in aminoacid or DNA sequences. It
is provided for free public use on a WWW server with a Java interface.
Availability : The server address is http://o2.db. uoa.gr/FT Contact :
shamodr@atlas.uoa.gr
相似文献
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Caitlin L. Rowe Kylie M. Wagstaff Sibil Oksayan Dominic J. Glover David A. Jans Gregory W. Moseley 《PloS one》2016,11(3)
Rabies virus P-protein is expressed as five isoforms (P1-P5) which undergo nucleocytoplasmic trafficking important to roles in immune evasion. Although nuclear import of P3 is known to be mediated by an importin (IMP)-recognised nuclear localization sequence in the N-terminal region (N-NLS), the mechanisms underlying nuclear import of other P isoforms in which the N-NLS is inactive or has been deleted have remained unresolved. Based on the previous observation that mutation of basic residues K214/R260 of the P-protein C-terminal domain (P-CTD) can result in nuclear exclusion of P3, we used live cell imaging, protein interaction analysis and in vitro nuclear transport assays to examine in detail the nuclear trafficking properties of this domain. We find that the effect of mutation of K214/R260 on P3 is largely dependent on nuclear export, suggesting that nuclear exclusion of mutated P3 involves the P-CTD-localized nuclear export sequence (C-NES). However, assays using cells in which nuclear export is pharmacologically inhibited indicate that these mutations significantly inhibit P3 nuclear accumulation and, importantly, prevent nuclear accumulation of P1, suggestive of effects on NLS-mediated import activity in these isoforms. Consistent with this, molecular binding and transport assays indicate that the P-CTD mediates IMPα2/IMPβ1-dependent nuclear import by conferring direct binding to the IMPα2/IMPβ1 heterodimer, as well as to a truncated form of IMPα2 lacking the IMPβ-binding autoinhibitory domain (ΔIBB-IMPα2), and IMPβ1 alone. These properties are all dependent on K214 and R260. This provides the first evidence that P-CTD contains a genuine IMP-binding NLS, and establishes the mechanism by which P-protein isoforms other than P3 can be imported to the nucleus. These data underpin a refined model for P-protein trafficking that involves the concerted action of multiple NESs and IMP-binding NLSs, and highlight the intricate regulation of P-protein subcellular localization, consistent with important roles in infection. 相似文献
9.
Zuluaga Diana L. Graham Neil S. Klinder Annett van Ommen Kloeke A. E. Elaine Marcotrigiano Angelo R. Wagstaff Carol Verkerk Ruud Sonnante Gabriella Aarts Mark G. M. 《Plant molecular biology》2019,101(1-2):65-79
Plant Molecular Biology - Overexpression of BoMYB29 gene up-regulates the aliphatic glucosinolate pathway in Brassica oleracea plants increasing the production of the anti-cancer metabolite... 相似文献
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