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1.
Noel H. Holmgren 《Brittonia》2018,70(1):115-139
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations. 相似文献
2.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes. 相似文献
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4.
D. J. Goyder 《Kew Bulletin》2008,63(2):331-333
Summary
Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed. 相似文献
5.
Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner.
The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate
larvae Galleria
mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host. 相似文献
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7.
A genetic transformation system has been developed for callus cells of Crataegus
aronia using Agrobacterium
tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with
5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different
types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red
colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli
were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this
is the first time to report an Agrobacterium-mediated transformation system in Crataegus
aronia. 相似文献
8.
Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile. 相似文献
9.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae. 相似文献
10.
Rosario Gil-Benso Javier Megías Teresa San-Miguel Sandra Pinto Robert C. Callaghan Concha López-Ginés Miguel Cerdá-Nicolás 《Cytotechnology》2017,69(4):539-550
Pleomorphic undifferentiated sarcoma (PUS), also called malignant fibrous histiocytoma, is a soft tissue sarcoma which occurs predominantly in the extremities. Its origin is a poorly defined mesenchymal cell, which derives to histiocytic and fibroblastic cells. The patient, a 58 year-old man, presented a lesion located in the forearm composed by spindle cells and multinucleated giant cells, which expressed vimentin and adopted a histological pattern formed by irregular-swirling fascicles. Cells were cultured in vitro and a new cell line was established. We characterized this new cell line by histological analyses, cytogenetics (using G-bands and spectral karyotype technique) and cytometric analyses. Cells were grown in culture for more than 100 passages. They had elongated or polygonal morphology. The cells presented a saturation rate of 70,980 cells/cm2, a plating efficiency of 21.5% and a mitotic index of 21 mitoses per field. The cell line was tumorigenic in nude mice. The ploidy study using flow cytometry revealed an aneuploid peak with a DNA index of 1.43. A side population was detected, demonstrating the presence of stem and progenitor cells. Cytogenetics showed a hypotriploid range with many clonal unbalanced rearrangements. Loss of p53 gene was evidenced by MLPA. We describe, for the first time, the characterization of a new human PUS TP53-null cell line called mfh-val2. Mfh-val2 presents a wide number of applications as a TP53-null cell line and a great interest in order to characterize genetic alterations influencing the oncogenesis or progression of PUS and to advance in the biological investigation of this tumor. 相似文献
11.
Sarawood Sungkaew Atchara Teerawatananon John A. N. Parnell Chris M. A. Stapleton Trevor R. Hodkinson 《Kew Bulletin》2008,63(4):669-673
Summary A new monotypic bamboo genus Phuphanochloa (Poaceae: Bambusoideae) from north-eastern Thailand is described, together with a new species, P. speciosa. 相似文献
12.
Lima FL de Carvalho MA Apolônio AC Bemquerer MP Santoro MM Oliveira JS Alviano CS Farias Lde M 《Journal of industrial microbiology & biotechnology》2008,35(2):103-110
Aggregatibacter (Actinobacillus) actinomycetemcomitans P7–20 strain isolated from a periodontally diseased patient has produced a bacteriocin (named as actinomycetemcomitin) that is
active against Peptostreptococcus anaerobius ATCC 27337. Actinomycetemcomitin was produced during exponential and stationary growth phases, and its amount decreased until
it disappeared during the decline growth phase. It was purified by ammonium sulphate precipitation (30–60% saturation), and
further by FPLC (mono-Q ionic exchange and Phenyl Superose hydrophobic interaction) and HPLC (C-18 reversed-phase). This bacteriocin
loses its activity after incubation at a pH below 7.0 or above 8.0, following heating for 30 min at 45°C, and after treatment
with proteolytic enzymes such as trypsin, α-chymotrypsin, and papain. Actinomycetemcomitin has a molecular mass of 20.3 KDa
and it represents a new bacteriocin from A. actinomycetemcomitans. 相似文献
13.
Nguyen Van Du 《Kew Bulletin》2008,63(3):491-493
Summary
Typhonium stigmatilobatum V. D. Nguyen, a new species from Vietnam, is described and illustrated. 相似文献
14.
Perugini LD Murphy JP Marshall D Brown-Guedira G 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(3):417-425
Powdery mildew is an important foliar disease in wheat, especially in areas with a cool or maritime climate. A dominant powdery
mildew resistance gene transferred to the hexaploid germplasm line NC99BGTAG11 from T. timopheevii subsp. armeniacum was mapped distally on the long arm of chromosome 7A. Differential reactions were observed between the resistance gene in
NC99BGTAG11 and the alleles of the Pm1 locus that is also located on chromosome arm 7AL. Observed segregation in F2:3 lines from the cross NC99BGTAG11 × Axminster (Pm1a) demonstrate that germplasm line NC99BGTAG11 carries a novel powdery mildew resistance gene, which is now designated as Pm37. This new gene is highly effective against all powdery mildew isolates tested so far. Analyses of the population with molecular
markers indicate that Pm37 is located 16 cM proximal to the Pm1 complex. Simple sequence repeat (SSR) markers Xgwm332 and Xwmc790 were located 0.5 cM proximal and distal, respectively, to Pm37. In order to identify new markers in the region, wheat expressed sequence tags (ESTs) located in the distal 10% of 7AL that
were orthologous to sequences from chromosome 6 of rice were targeted. The two new EST-derived STS markers were located distal
to Pm37 and one marker was closely linked to the Pm1a region. These new markers can be used in marker-assisted selection schemes to develop wheat cultivars with pyramids of powdery
mildew resistance genes, including combinations of Pm37 in coupling linkage with alleles of the Pm1 locus. 相似文献
15.
Brian Schrire 《Kew Bulletin》2008,63(3):477-479
Summary Eleven species comprising the Madagascan genus Vaughania are subsumed within the large pantropical genus Indigofera. Six new combinations are made; the remaining species were originally described in Indigofera. 相似文献
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17.
A new Dactylella species, Dactylella alba was isolated from the ascospores of Orbilia alba collected in Wenshan County, Yunnan Province, China. Conidiophores were either not branched or occasionally branched, bearing
divergent sterigmata on the tip with single conidium on each. Conidia were elongated ellipsoids, 1–2 septate, mostly 1 septate.
By combining the ITS sequence with morphological characteristics, a new anamorphic species is described and illustrated together
with its teleomorph. 相似文献
18.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora:
Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii
,
Rumex densiflorus var. pycnanthus
,
R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage. 相似文献
19.
M. J. E. Coode 《Kew Bulletin》2010,65(3):355-399
The Ganitrus group of Elaeocarpus L. (incl. Elaeocarpus Sect. Ptilanthus Schltr.) as found in Malesia is examined and some understanding reached. The group is more complex and speciose in eastern
Malesia, especially in Papuasia (with the Philippines, Sulawesi and Maluku somewhat less rich) than in western and central
Malesia. E. angustifolius Blume (syn. E. ganitrus & E. sphaericus auctt. mult.) — the source of the ornamental beads known as rudraksha of eastern commerce, from which malas or rosaries are made — is considered to be very variable in Malesia and probably varies further in the extremes of its range;
outside Malesia the Ganitrus group is represented by ‘E. angustifolius s.l.’ only. The following species are recognised: E. altisectus Schltr. with a new subsp. carrii Coode from New Guinea; E. angustifolius Blume; E. avium Coode sp. nov. from New Guinea; E. buderi Coode; E. dolichostylus Schltr. with E. chloranthus treated as var. chloranthus (A. C. Sm.) Coode from New Guinea, with a new var. elliptifolius Coode from the Talaud/Sangihe Is. and a new var. hentyi Coode (replacing and re-interpreting subsp. collinus Coode) from New Guinea; E. fulvus Elmer; E. kaniensis Schltr.; E. ornatus Coode sp. nov. from New Guinea; E. osiae Coode sp. nov. from Bougainville I.; E. ptilanthus Schltr.; E. ramiflorus Merr. and E. trichopetalus Merr. & Quisumb. — a total of 12 species although the last two are perhaps not truly distinct from E. angustifolius. The stone sculpturing is discussed and some useful characters revealed. Attention is drawn to a collection from mid-altitude
in Papua New Guinea, inadequately known but probably a new species in this group. 相似文献
20.
Iain Darbyshire 《Kew Bulletin》2008,63(2):261-268
Summary Three new species are described in Barleria L. sect. Stellatohirta M. Balkwill from tropical Africa: B. aristata from south-central Tanzania, B. aenea from south-western Tanzania and northeast Zambia, and B. purpureotincta from south-western Zambia. Their affinities and conservation status are discussed. 相似文献