Ventilator associated pneumonia : analyses of volatile fingerprints for identification of causative microorganisms, assessment of anti-fungals and use of in vitro models for early clinical sample prediction

This study has involved the analysis of volatile fingerprints using a hybrid electronic nose (e-nose) to discriminate between and diagnose the microorganisms which cause ventilator–associated pneumonia (VAP), one of the most important infections in the hospital environment. This infection occurs in hospitalised patients with 48-72 hrs of mechanical ventilation. VAP diagnostics still remains a problem due to the lack of a precise diagnostic tool. The current tests are mostly based on quantitative cultures of samples from the lower lung airways with clinical findings, which do not often result in accurate diagnoses of the disease. Cont/d.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Distinguishing colour variants of <i>Serapias perez-chiscanoi</i> (Orchidaceae) from related taxa on the Iberian Peninsula

Serapias perez-chiscanoi has a stable and uniform appearance with green flowers. Throughout its distribution area, however, plants have been found with deviant pink to red flowers that show similarities with other taxa that are occasionally pale flowered. S. perez-chiscanoi is easy to differentiate from S. cordigera subsp. cordigera by the colour of the flowers (S. cordigera subsp. cordigera has red to purple flowers) and the fact that the hypochile dimensions of S. perez-chiscanoi are significantly smaller. It is, however, more difficult to distinguish it from individuals of S. cordigera subsp. gentilii with pale flowers, which occur frequently. The two taxa differ in colour pattern and floral dimensions, especially the hypochile length, which is shorter in S. perez-chiscanoi. Pale-flowered individuals of another species, S. parviflora, are easily distinguished by their significantly smaller flowers. S. perez-chiscanoi occurs in Spain in the autonomous regions of Extremadura and Castilla-La Mancha and in Portugal, S. cordigera subsp. gentilii seems to occur along the coastal regions of SW Portugal, while S. cordigera subsp. cordigera and S. parviflora are distributed throughout the Iberian Peninsula

Heterochromatin distribution in selected taxa of the 42-chromosomes Orchis s. l.

In six 42-chromosomes taxa belonging to genus Orchis s. l. heterochromatin location and distribution and staining properties were analysed by means of C-banding and of the fluorochromes 4'-6-diamino-2-phenylindole-2HCl (DAPI) and Hoechst 33258. Most species could be distinguished on the basis of heterochromatin amounts and distribution. In the species O. mascula and O. provincialis most DAPI-positive sites did not co-localize with C-bands. DAPI revealed bright fluorescence at telomeric or subtelomeric regions of numerous chromosomes of O. mascula and particularly large/bright blocks at the telomeres of O. provincialis. In O. x penzigiana (Orchis mascula ssp. ichnusae x O. provincialis) overall heterochromatin distribution followed that of the parental species. In Neotinea group all DAPI positive bands co-localize with C-bands, but have different distribution in the taxa analysed. Present and literature data indicate a high level of plasticity of heterochromatin organization in Orchis s. l., and suggest evolutionary pathways in agreement with recent molecular data

Localization of rDNA loci by Fluorescent In Situ

The 18S-5.8S-25S (pTa71) and 5S (pTa794) rDNA were used as probes for in situ hybridization to reveal the physical localisation of ribosomal genes in some species of orchids. Earlia robertiana (2n = 36) revealed one chromo- some pair with both pTa71 and pTa794 signals; Anacamptis papilionacea (2n = 32) showed two pairs of 5S rDNA and one pair of 18S-25S sites; A. morio (2n = 36) had two pairs of 18S-25S rDNA and one pair of 5S sites; the natural hybrid A. x gennarii (A. morio x A. papilionacea, 34 chromosomes) showed three 18S-25S and three 5S rDNA sites; finally, A. collina (2n = 36) showed only one pair of 18S-25S rDNA and one pair of 5S rDNA sites. This preliminary contribution indicates that repetitive DNA sequences in orchids may prove very useful for the understanding of evolutionary trends

Advances in the Study of Orchidinae Subtribe (Orchidaceae) Species with 40,42-Chromosomes in the Mediterranean Region

This study presents an updated analysis of cytogenetic data for several species within the 40,42-chromosome genera of the subtribe Orchidinae. The research includes insights into the distribution of heterochromatin obtained using C-banding and fluorochrome techniques. Our investigation confirmed variation in the distribution of heterochromatin and repetitive DNA sequences among species pertaining to Neotinea s.l. and Orchis s.str. These variations also potentially contribute to the diversification of these species. Cytogenetic analyses of the Neotinea group demonstrated that both H33258 and DAPI staining result in blocks of fluorescent regions on numerous chromosomes. Particular attention was paid to the cytological composition of the polyploid Neotinea commutata, focusing on its potential origin. Based on the karyological results acquired, a hypothesis concerning the origin of N. commutata is proposed. The most noteworthy revelations regard the O. mascula complex. In these species, the telomeric areas of all chromosome sets display extensive heterochromatin. Fluorochrome staining revealed telomeric blocks on many chromosomes that were not seen with Giemsa staining. This highlighted a distinct feature of O. mascula, where particularly large C-bands surrounding the centromeric regions of multiple chromosomes were found. However, in O. mascula, O. provincialis, O. pauciflora, and O. patens, C+ chromatin may not show a significant response to fluorochrome Hoechst or DAPI+ staining. The unique cytomorphological arrangement observed in the O. mascula species, unlike other members of the O. mascula complex, suggest epigenetic phenomena. Additional data are presented for the genera Dactylorhiza and Gymnadenia. A deeper understanding of the diversity of chromosomal structures among these orchids promises to shed light on the mechanisms underlying speciation, adaptation, and the remarkable diversity characteristic of the Orchidaceae family

Comparative Cytogenetic of the 36-Chromosomes Genera of Orchidinae Subtribe (Orchidaceae) in the Mediterranean Region: A Summary and New Data

This article provides a summary of the current knowledge on the cytogenetics of four genera, which are all composed of 36 chromosomes, within the Orchidinae subtribe (Orchidaceae). Previous classical studies have revealed differences in karyomorphology among these genera, indicating genomic diversity. The current study includes an analysis of the current knowledge with an update of the karyotype of 47 species with 36 chromosomes from the genera Anacamptis, Serapias, Himantoglossum, and Ophrys. The study discusses comparisons of karyotypes among these genera that used traditional techniques as well as karyotype asymmetry relationships with various asymmetry indices. Additionally, the study reports new findings on polyploidy in Anacamptis pyramidalis and Serapias lingua, which were observed through karyotype and meiotic metaphase analyses in EMC. Moreover, the study detected B chromosomes for the first time in A. papilionacea and A. palustris. The article also describes the use of fluorescent in situ hybridization in some specimens of A. papilionacea and A. collina to locate different sites of the 18S-5.8S-25S rDNA and 5S rDNA ribosomal complexes on chromosomes. The information derived from these cytogenetic analyses was used to refine the classification of these orchids and identify evolutionary relationships among different species and genera