Slow breathing reduces sympathoexcitation in COPD

Neurohumoral activation has been shown to be present in hypoxic patients with chronic obstructive pulmonary disease (COPD). The aims of the present study were to investigate whether there is sympathetic activation in COPD patients in the absence of hypoxia and whether slow breathing has an impact on sympathoexcitation and baroreflex sensitivity. Efferent muscle sympathetic nerve activity, blood pressure, cardiac frequency and respiratory movements were continuously measured in 15 COPD patients and 15 healthy control subjects. Baroreflex sensitivity was analysed by autoregressive spectral analysis and the alpha-angle method. At baseline, sympathetic nerve activity was significantly elevated in COPD patients and baroreflex sensitivity was decreased (5.0+/-0.6 versus 8.9+/-0.8 ms.mmHg(-1)). Breathing at a rate of 6 breaths.min(-1) caused sympathetic activity to drop significantly in COPD patients (from 61.3+/-4.6 to 53.0+/-4.3 bursts per 100 heartbeats) but not in control subjects (39.2+/-3.2 versus 37.5+/-3.3 bursts per 100 heartbeats). In both groups, slow breathing significantly enhanced baroreflex sensitivity. In conclusion, sympathovagal imbalance is present in normoxic chronic obstructive pulmonary disease patients. The possibility of modifying these changes by slow breathing may help to better understand and influence this systemic disease

Molecular species identification of Central European ground beetles (Coleoptera: Carabidae) using nuclear rDNA expansion segments and DNA barcodes

<p>Abstract</p> <p>Background</p> <p>The identification of vast numbers of unknown organisms using DNA sequences becomes more and more important in ecological and biodiversity studies. In this context, a fragment of the mitochondrial cytochrome <it>c </it>oxidase I (COI) gene has been proposed as standard DNA barcoding marker for the identification of organisms. Limitations of the COI barcoding approach can arise from its single-locus identification system, the effect of introgression events, incomplete lineage sorting, numts, heteroplasmy and maternal inheritance of intracellular endosymbionts. Consequently, the analysis of a supplementary nuclear marker system could be advantageous.</p> <p>Results</p> <p>We tested the effectiveness of the COI barcoding region and of three nuclear ribosomal expansion segments in discriminating ground beetles of Central Europe, a diverse and well-studied invertebrate taxon. As nuclear markers we determined the 18S rDNA: V4, 18S rDNA: V7 and 28S rDNA: D3 expansion segments for 344 specimens of 75 species. Seventy-three species (97%) of the analysed species could be accurately identified using COI, while the combined approach of all three nuclear markers provided resolution among 71 (95%) of the studied Carabidae.</p> <p>Conclusion</p> <p>Our results confirm that the analysed nuclear ribosomal expansion segments in combination constitute a valuable and efficient supplement for classical DNA barcoding to avoid potential pitfalls when only mitochondrial data are being used. We also demonstrate the high potential of COI barcodes for the identification of even closely related carabid species.</p

A DNA barcode library for ground beetles of Germany: the genus Agonum Bonelli, 1810 (Insecta, Coleoptera, Carabidae)

The ground beetle genus Agonum Bonelli, 1810 is a large genus of the tribe Platynini with many species that show high amounts of intraspecific variations, making a correct identification challenging. As part of the German Barcode of Life initiative, this publication provides a comprehensive DNA barcode library for species of Agonum that are reported for Germany. In total, DNA barcodes from 258 beetles and 23 species were analysed using the Barcode of Life Data System (BOLD) workbench, including sequences from former studies and 68 newly-generated sequences. The neighbour-joining analyses, based on K2P distances, revealed distinct clustering for all studied species, with unique Barcode Index Numbers (BINs) for 15 species (65%). BIN sharing but distinct clustering was found for three species pairs: Agonum micans/Agonum scitulum, Agonum impressum/Agonum sexpunctatum and Agonum duftschmidi/Agonum emarginatum. The given dataset and its analysis represent another important step in generating a comprehensive DNA barcode library for the ground beetles of Germany and Central Europe in terms of modern biodiversity research

A DNA barcode library for ground beetles of Germany: the genus Amara Bonelli, 1810 (Insecta, Coleoptera, Carabidae)

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About Notiophilus Duméril, 1806 (Coleoptera, Carabidae): Species delineation and phylogeny using DNA barcodes

The genus Notiophilus Duméril, 1806 is a distinctive taxon of small, diurnal and morphologically similar beetles exhibiting large eyes and widened second elytral intervals. In this study we analysed the effectiveness of DNA barcodes to discriminate 67 specimens that represent 8 species of Notiophilus from Central Europe. Interspecific K2P distances below 2.2% were found for N. biguttatus (Fabricius, 1779) and N. quadripunctatus Dejean, 1826, whereas intraspecific distances with values > 2.2% were revealed for N. rufipes Curtis, 1829. An additional phylogenetic analysis of all available species revealed a close relationship of N. directus Casey, 1920, N. semistriatus Say, 1823, N. simulator Fall, 1906 and N. sylvaticus Dejean, 1831, possibly indicating a radiation of these species in North America. Low support values of most other nodes, however, do not allow additional phylogenetic conclusions

A DNA barcode library for ground beetles of Germany: the genus Pterostichus Bonelli, 1810 and allied taxa (Insecta, Coleoptera, Carabidae)

Species of the ground beetle genus Pterostichus Bonelli, 1810 are some of the most common carabids in Europe. This publication provides a first comprehensive DNA barcode library for this genus and allied taxa including Abax Bonelli, 1810, Molops Bonelli, 1810, Poecilus Bonelli, 1810, and Stomis Clairville, 1806 for Germany and Central Europe in general. DNA barcodes were analyzed from 609 individuals that represent 51 species, including sequences from previous studies as well as more than 198 newly generated sequences. The results showed a 1:1 correspondence between BIN and traditionally recognized species for 44 species (86%), whereas two (4%) species were characterized by two BINs. Three BINs were found for one species (2%), while one BIN for two species was revealed for two species pairs (8%). Low interspecific distances with maximum pairwise K2P values below 2.2% were found for four species pairs. Haplotype sharing was found for two closely related species pairs: Pterostichus adstrictus Eschscholtz, 1823/Pterostichus oblongopunctatus (Fabricius, 1787) and Pterostichus nigrita Paykull, 1790/Pterostichus rhaeticus Heer, 1837. In contrast to this, high intraspecific sequence divergences with values above 2.2% were shown for three species (Molops piceus (Panzer, 1793), Pterostichus panzeri (Panzer, 1805), Pterostichus strenuus (Panzer, 1793)). Summarizing the results, the present DNA barcode library does not only allow the identification of most of the analyzed species, but also provides valuable information for alpha-taxonomy as well as for ecological and evolutionary research. This library represents another step in building a comprehensive DNA barcode library of ground beetles as part of modern biodiversity research

About Notiophilus Duméril, 1806 (Coleoptera, Carabidae): Species delineation and phylogeny using DNA barcodes

The genus Notiophilus Duméril, 1806 is a distinctive taxon of small, diurnal and morphologically similar beetles exhibiting large eyes and widened second elytral intervals. In this study we analysed the effectiveness of DNA barcodes to discriminate 67 specimens that represent 8 species of Notiophilus from Central Europe. Interspecific K2P distances below 2.2% were found for N. biguttatus (Fabricius, 1779) and N. quadripunctatus Dejean, 1826, whereas intraspecific distances with values > 2.2% were revealed for N. rufipes Curtis, 1829. An additional phylogenetic analysis of all available species revealed a close relationship of N. directus Casey, 1920, N. semistriatus Say, 1823, N. simulator Fall, 1906 and N. sylvaticus Dejean, 1831, possibly indicating a radiation of these species in North America. Low support values of most other nodes, however, do not allow additional phylogenetic conclusions

A DNA barcode library for ground beetles (Insecta, Coleoptera, Carabidae) of Germany: The genus Bembidion Latreille, 1802 and allied taxa

As molecular identification method, DNA barcoding based on partial cytochrome c oxidase subunit 1 (COI) sequences has been proven to be a useful tool for species determination in many insect taxa including ground beetles. In this study we tested the effectiveness of DNA barcodes to discriminate species of the ground beetle genus Bembidion and some closely related taxa of Germany. DNA barcodes were obtained from 819 individuals and 78 species, including sequences from previous studies as well as more than 300 new generated DNA barcodes. We found a 1:1 correspondence between BIN and traditionally recognized species for 69 species (89%). Low interspecific distances with maximum pairwise K2P values below 2.2% were found for three species pairs, including two species pairs with haplotype sharing (Bembidion atrocaeruleum/Bembidion varicolor and Bembidion guttula/Bembidion mannerheimii). In contrast to this, deep intraspecific sequence divergences with distinct lineages were revealed for two species (Bembidion geniculatum/Ocys harpaloides). Our study emphasizes the use of DNA barcodes for the identification of the analyzed ground beetles species and represents an important step in building-up a comprehensive barcode library for the Carabidae in Germany and Central Europe as well