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Species Designation (species + designation)

Distribution by Scientific Domains

Life Sciences	75%

Selected Abstracts

Survival After Lung Transplantation of Cystic Fibrosis Patients Infected with Burkholderia cepacia Complex

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2008
B. D. Alexander
Within the Burkholderia cepacia complex (Bcc), B. cenocepacia portends increased mortality compared with other species. We investigated the impact of Bcc infection on mortality and re-infection following lung transplant (LT). Species designation for isolates from Bcc-infected patients was determined using 16S rDNA and recA gene analyses. Of 75 cystic fibrosis patients undergoing LT from September 1992 to August 2002, 59 had no Bcc and 16 had Bcc (including 7 B. cenocepacia) isolated in the year before LT. Of the latter, 87.5% had Bcc recovered after transplantation, and all retained their pretransplant strains. Survival was 97%, 92%, 76% and 63% for noninfected patients; 89%, 89%, 67% and 56% for patients infected with Bcc species other than B. cenocepacia; and 71%, 29%, 29% and 29% for patients with B. cenocepacia (p = 0.014) at 1 month, 1 year, 3 years and 5 years, respectively. Patients infected with B. cenocepacia before transplant were six times more likely to die within 1 year of transplant than those infected with other Bcc species (p = 0.04) and eight times than noninfected patients (p < 0.00005). Following LT, infection with Bcc species other than B. cenocepacia does not significantly impact 5-year survival whereas infection with B. cenocepacia pretransplant is associated with decreased survival. [source]

The separation of Pterodroma madeira (Zino's Petrel) from Pterodroma feae (Fea's Petrel) (Aves: Procellariidae)

IBIS, Issue 2 2008
FRANCIS ZINO
The taxonomic status of petrels from the North East Atlantic has long been a matter of debate. Breeding colonies of petrels occurring on the islands of Madeira, Bugio and Cape Verde were originally thought to be outlying populations of the polytypic species Pterodroma mollis. Subsequent taxonomic treatments have varied considerably in their classification of birds from these islands. The petrel populations on Madeira and Bugio represent some of Europe's rarest breeding birds and their exact species designation, and hence relation to conservation mandates, is a question of considerable importance. In this study we use molecular techniques alongside more traditional taxonomic characters to confirm the existence of two species of the genus Pterodroma in the Archipelago of Madeira. We also discuss identification of these species in the field and the implications for their conservation management. [source]

Phytophthora andina sp. nov., a newly identified heterothallic pathogen of solanaceous hosts in the Andean highlands

PLANT PATHOLOGY, Issue 4 2010
R. F. Oliva
A blight disease on fruits and foliage of wild and cultivated Solanum spp. was found to be associated with a new species of Phytophthora. The proposed novel species is named Phytophthora andina Adler & Flier, sp. nov. based on morphological characteristics, pathogenicity assays, mitochondrial DNA haplotyping, AFLP fingerprinting and nuclear and mitochondrial DNA sequence analyses. Isolates of P. andina (n = 48) from the Andean highland tropics of Ecuador were collected from 1995 to 2006. Phytophothora andina is closely related to P. infestans and has semipapillate, ellipsoidal sporangia borne on sympodially branched sporangiophores. It is heterothallic and produces amphigynous antheridia. The species consists of several clonal lineages, including the EC-2 and EC-3 RFLP lineages, which were described previously as P. infestans. Approximately 75% of isolates react as compatibility type A2 when paired with an A1 compatibility type isolate of P. infestans. However, when A2 isolates from the Anarrhichomenum section of Solanum were paired in all combinations, viable oospores were obtained in several crosses, suggesting that there is a unique compatibility interaction in P. andina that is complementary to that described in P. infestans. Nuclear and mitochondrial sequence analysis supported the species designation of P. andina. This newly identified heterothallic pathogen shares a common ancestor with P. infestans and may have arisen from hybridization events with sister taxa in the Andes. [source]

World-wide genetic differentiation of Eubalaena: questioning the number of right whale species

MOLECULAR ECOLOGY, Issue 11 2000
H. C. Rosenbaum
Abstract Few studies have examined systematic relationships of right whales (Eubalaena spp.) since the original species descriptions, even though they are one of the most endangered large whales. Little morphological evidence exists to support the current species designations for Eubalaena glacialis in the northern hemisphere and E. australis in the southern hemisphere. Differences in migratory behaviour or antitropical distribution between right whales in each hemisphere are considered a barrier to gene flow and maintain the current species distinctions and geographical populations. However, these distinctions between populations have remained controversial and no study has included an analysis of all right whales from the three major ocean basins. To address issues of genetic differentiation and relationships among right whales, we have compiled a database of mitochondrial DNA control region sequences from right whales representing populations in all three ocean basins that consist of: western North Atlantic E. glacialis, multiple geographically distributed populations of E. australis and the first molecular analysis of historical and recent samples of E. glacialis from the western and eastern North Pacific Ocean. Diagnostic characters, as well as phylogenetic and phylogeographic analyses, support the possibility that three distinct maternal lineages exist in right whales, with North Pacific E. glacialis being more closely related to E. australis than to North Atlantic E. glacialis. Our genetic results provide unequivocal character support for the two usually recognized species and a third distinct genetic lineage in the North Pacific under the Phylogenetic Species Concept, as well as levels of genetic diversity among right whales world-wide. [source]