970 resultados para description interprétative
Resumo:
The taxonomic position of Actinobacillus capsulatus, a member of the family Pasteurellaceae found in rabbits, hares and hamsters, has been challenged. 16S rRNA gene (rrs) sequence data show the species to be heterogeneous. Using a polyphasic approach, 23 strains that were identified previously as belonging, or closely related, to A. capsulatus were analysed. Eighty characters were included in the phenotypic analysis. Phylogenetic analysis was done based on rrs, rpoB, infB and recN sequences. In addition, the recN sequence similarities were used to calculate the whole-genome sequence relatedness of all strains investigated as well as that with other members of the family Pasteurellaceae. The phenotypic analysis allowed identification of five groups. The major group of 17 strains could be classified as A. capsulatus. Two hamster isolates were closely related to A. capsulatus but differed in a few characters. Single isolates from a rabbit and snowshoe-hare were phenotypically related to Actinobacillus suis. One rabbit isolate was related to the genus Mannheimia, while another isolate could not be classified phenotypically with known taxa. The phylogenetic analysis confirmed the phenotypic grouping. In contrast to the rrs-based tree, the A. capsulatus strains clustered unambiguously with the type species and related species of the genus Actinobacillus in the rpoB-, infB- and recN-based trees. Genome similarity comparison using recN finally confirmed the high genomic relationship of the A. capsulatus strains with the type species and related species of the genus Actinobacillus and allowed a clear assignment of the other unrelated strains to the phenotypic and phylogenetic clusters outlined. The present findings allow the description of A. capsulatus to be emended and separate it more clearly from other species, both phenotypically and genotypically. The type strain of A. capsulatus is CCUG 12396(T) (=Frederiksen 243(T)=ATCC 51571(T)=NCTC 11408(T)=CIP 103283(T)).
Resumo:
Principles and guidelines are presented to ensure a solid scientific standard of papers dealing with the taxonomy of taxa of Pasteurellaceae Pohl 1981. The classification of the Pasteurellaceae is in principle based on a polyphasic approach. DNA sequencing of certain genes is very important for defining the borders of a taxon. However, the characteristics that are common to all members of the taxon and which might be helpful for separating it from related taxa must also be identified. Descriptions have to be based on as many strains as possible (inclusion of at least five strains is highly desirable), representing different sources with respect to geography and ecology, to allow proper characterization both phenotypically and genotypically, to establish the extent of diversity of the cluster to be named. A genus must be monophyletic based on 16S rRNA gene sequence-based phylogenetic analysis. Only in very rare cases is it acceptable that monophyly can not be achieved by 16S rRNA gene sequence comparison. Recently, the monophyly of genera has been confirmed by sequence comparison of housekeeping genes. In principle, a new genus should be recognized by a distinct phenotype, and characters that separate the new genus from its neighbours should be given clearly. Due to the overall importance of accurate classification of species, at least two genotypic methods are needed to show coherence and for separation at the species level. The main criterion for the classification of a novel species is that it forms a monophyletic group based on 16S rRNA gene sequence-based phylogenetic analysis. However, some groups might also include closely related species. In these cases, more sensitive tools for genetic recognition of species should be applied, such as DNA-DNA hybridizations. The comparison of housekeeping gene sequences has recently been used for genotypic definition of species. In order to separate species, phenotypic characters must also be identified to recognize them, and at least two phenotypic differences from existing species should be identified if possible. We recommend the use of the subspecies category only for subgroups associated with disease or similar biological characteristics. At the subspecies level, the genotypic groups must always be nested within the boundaries of an existing species. Phenotypic cohesion must be documented at the subspecies level and separation between subspecies and related species must be fully documented, as well as association with particular disease and host. An overview of methods previously used to characterize isolates of the Pasteurellaceae has been given. Genotypic and phenotypic methods are separated in relation to tests for investigating diversity and cohesion and to separate taxa at the level of genus as well as species and subspecies.
Resumo:
Airway access is needed for a number of experimental animal models, and the majority of animal research is based on mouse models. Anatomical conditions in mice are small, and the narrow glottic opening allows intubation only with a subtle technique. We therefore developed a microscopic endotracheal intubation method with a wire guide technique in mice anaesthetized with halothane in oxygen. The mouse is hung perpendicularly with its incisors on a thread fixed on a vertical plate. The tongue is placed with a pair of forceps between the left hand's thumb and forefinger and slightly pulled, while the neck and thorax are positioned using the third and fourth fingers. By doing so, the neck can be slightly stretched, which allows optimal visualization of the larynx and the vocal cords. To ensure a safe intubation, a fine wire guide is placed under vision between the vocal cords and advanced about 5 mm into the trachea. An intravenous 22G x 1 in. plastic or Teflon catheter is guided over this wire. In a series of 41 mice, between 21 and 38 g, the success rate for the first intubation attempt was >95%. Certainty of the judgement procedure was 100% and success rate was higher using the described method when compared with a transillumination method in a further series. The technique is safe, less invasive than tracheostomy and suitable for controlled ventilation and pulmonary substance application.
Resumo:
BACKGROUND: Congenital retinal macrovessels are large aberrant branches of retinal arteries or veins that cross the macula. We present three patients with a unilateral congenital retinal macrovessel and we conduct a review of the literature. PATIENTS AND METHODS: A 22-year-old man complaining of chronic headache as well as two other men, 18 and 23 years old, respectively, during a routine ophthalmological examination, were found with a unilateral congenital retinal macrovessel each. A thorough ophthalmological examination was performed, including colour fundus photography in all three patients and fluorescein angiography in two of the patients. We followed them up for five years. THERAPY AND OUTCOME: Investigation revealed a unilateral venous congenital retinal macrovessel in all patients. Clinical findings and visual acuity remained unchanged throughout the entire follow-up period. No complications were recorded. CONCLUSIONS: Congenital retinal macrovessels are rare and they tend to remain stable. Visual acuity is preserved in most cases. Complications occur only occasionally and have been described in the literature. Differential diagnosis from other arteriovenous malformations affecting multiple organs is necessary.
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OBJECTIVE: To describe the prevalence, main characteristics, and treatment of severe autoimmune cytopenias [autoimmune hemolytic anemia (AIHA), autoimmune thrombocytopenic purpura (AITP)] in patients with chronic hepatitis C virus (HCV) infection. METHODS: Retrospective chart review of patients with chronic HCV infection seen at our institution. Two additional departments contributed eight more patients to assess therapy of HCV-related autoimmune cytopenias. RESULTS: Eight patients (seven AITP, one AIHA) fulfilled the inclusion criteria in our population of 4345 HCV-infected patients. The number of patients with AITP was much greater than would be expected by chance (P<0.0001). Patients with HCV-related AITP were older and demonstrated more immunological markers than a group of 40 controls. Eight additional patients (six AITP, two Evans syndrome) were included. We only assessed the response for AITP patients because of the single case of AIHA. Patients with AITP had a poor response to initial corticosteroids [one complete response (CR), three partial response (PR), and four failures]. Intravenous immunoglobulins led to transient efficacy in three of four patients. In second-line therapy, five of seven patients responded to splenectomy. Rituximab proved effective in increasing platelets in two patients. Of eight patients treated with antiviral therapy (IFN-alpha+/-ribavirin), five responded (three CR, two PR). CONCLUSION: AITP occurs more commonly in patients with chronic HCV infection than would be expected by chance. HCV-positive AITP requires a treatment strategy different from that used in HCV-negative AITP. On the basis of the results from our study and a literature analysis, we propose an algorithm for treatment of severe HCV-related autoimmune cytopenias.
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In contrast-enhanced (CE) MR myelography, hyperintense signal outside the intrathecal space in T1-weighted sequences with spectral presaturation inversion recovery (SPIR) is usually considered to be due to CSF leakage. We retrospectively investigated a hyperintense signal at the apex of the lung appearing in this sequence in patients with SIH (n = 5), CSF rhinorrhoea (n = 2), lumbar spine surgery (n = 1) and in control subjects (n = 6). Intrathecal application of contrast agent was performed in all patients before MR examination, but not in the control group. The reproducible signal increase was investigated with other fat suppression techniques and MR spectroscopy. All patients and controls showed strongly hyperintense signal at the apex of the lungs imitating CSF leakage into paraspinal tissue. This signal increase was identified as an artefact, caused by spectroscopically proven shift and broadening of water and lipid resonances (1-2 ppm) in this anatomical region. Only patients with SIH showed additional focal enhancement along the spinal nerve roots and/or in the spinal epidural space. In conclusion CE MR myelography with spectral selective fat suppression shows a reproducible cervicothoracic artefact, imitating CSF leakage. Selective water excitation technique as well as periradicular and epidural contrast collections may be helpful to discriminate between real pathological findings and artefacts.
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From october 2000 to march 2003 the project has been coordinated by the institute of social work and welfare studies of the TU Dresden and financed by the European Commission (INCO-COPERNICUS-Programme). It was an international cooperation between the TU Dresden (Germany), the University of Internal Affairs and the National Technical University in Kharkiv (Ukraine), the research institute AREA in Valenciá (Spain) and the Belgorod Juridical Institute of the Ministry of Internal Affairs (Russia) which was established for improving the knowledge base of drug prevention activities by the East European partners. The overall aim of the project was the analysis and elaboration of approaches to drug and addiction prevention. Under consideration of the specific conditions within the East-European countries this work should contribute to the development of pluralistic approaches towards health promotion which are embedded into an intercultural, European horizon.
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This investigation was based on 23 isolates from several European countries collected over the past 30 years, and included characterization of all isolates. Published data on amplified fragment length polymorphism typing of isolates representing all biovars as well as protein profiles were used to select strains that were then further characterized by polyamine profiling and sequencing of 16S rRNA, infB, rpoB and recN genes. Comparison of 16S rRNA gene sequences revealed a monophyletic group within the avian 16S rRNA group of the Pasteurellaceae, which currently includes the genera Avibacterium, Gallibacterium and Volucribacter. Five monophyletic subgroups related to Gallibacterium anatis were recognized by 16S rRNA, rpoB, infB and recN gene sequence comparisons. Whole-genome similarity between strains of the five subgroups and the type strain of G. anatis calculated from recN sequences allowed us to classify them within the genus Gallibacterium. In addition, phenotypic data including biochemical traits, protein profiling and polyamine patterns clearly indicated that these taxa are related. Major phenotypic diversity was observed for 16S rRNA gene sequence groups. Furthermore, comparison of whole-genome similarities, phenotypic data and published data on amplified fragment length polymorphism and protein profiling revealed that each of the five groups present unique properties that allow the proposal of three novel species of Gallibacterium, for which we propose the names Gallibacterium melopsittaci sp. nov. (type strain F450(T) =CCUG 36331(T) =CCM 7538(T)), Gallibacterium trehalosifermentans sp. nov. (type strain 52/S3/90(T) =CCUG 55631(T) =CCM 7539(T)) and Gallibacterium salpingitidis sp. nov. (type strain F150(T) =CCUG 15564(T) =CCUG 36325(T) =NCTC 11414(T)), a novel genomospecies 3 of Gallibacterium and an unnamed taxon (group V). An emended description of the genus Gallibacterium is also presented.
Resumo:
In this paper we present XSAMPL3D, a novel language for the high-level representation of actions performed on objects by (virtual) humans. XSAMPL3D was designed to serve as action representation language in an imitation-based approach to character animation: First, a human demonstrates a sequence of object manipulations in an immersive Virtual Reality (VR) environment. From this demonstration, an XSAMPL3D description is automatically derived that represents the actions in terms of high-level action types and involved objects. The XSAMPL3D action description can then be used for the synthesis of animations where virtual humans of different body sizes and proportions reproduce the demonstrated action. Actions are encoded in a compact and human-readable XML-format. Thus, XSAMPL3D describtions are also amenable to manual authoring, e.g. for rapid prototyping of animations when no immersive VR environment is at the animator's disposal. However, when XSAMPL3D descriptions are derived from VR interactions, they can accomodate many details of the demonstrated action, such as motion trajectiories,hand shapes and other hand-object relations during grasping. Such detail would be hard to specify with manual motion authoring techniques only. Through the inclusion of language features that allow the representation of all relevant aspects of demonstrated object manipulations, XSAMPL3D is a suitable action representation language for the imitation-based approach to character animation.
Resumo:
The aim of this study was to improve the definition and identification of a group of veterinarily important bacteria referred to as the [Pasteurella] aerogenes-[Pasteurella] mairii-[Actinobacillus] rossii complex. These organisms have mainly been isolated from the reproductive and intestinal tracts of pigs and in most cases have been considered as opportunistic pathogens. A collection of 87 strains were characterized by phenotypic analysis from which 41 strains were selected for 16S rRNA gene sequence comparison, out of which 23 have been sequenced in the present study. One group of 21 strains phenotyped as biovars 1, 3-5, 9-11, 19 and 25-27, including the type strain of [P.] aerogenes, showed 16S rRNA gene sequence similarities of 99.6 % or higher; another group of 18 strains including biovars 2, 6-8, 12-15, 21, 23, 24 and 26A and the type strain of [A.] rossii showed 97.8 % or higher 16S rRNA gene sequence similarity. Between the two groups, 93.8-95.7 % 16S rRNA gene sequence similarity was observed. Strains of [P.] mairii showed 99.5 % similarity, with 95.5-97.2 and 93.8-95.5 % similarity to strains of [P.] aerogenes and [A.] rossii, respectively. Four strains could not be classified with any of these groups and belonged to other members of Pasteurellaceae. Comparisons were also made to DNA-DNA hybridization data. Biovars 1, 9, 10, 11 and 19, including the type strain of [P.] aerogenes, linked at 70 % DNA reassociation, whereas strains identified as biovars 2, 6, 7, 8, 12, 15 and 21 of [P.] aerogenes linked at 81 %. The latter group most likely represents [A.] rossii based on the 16S rRNA gene sequence comparisons. DNA reassociation between the [P.] aerogenes and [A.] rossii groups was at most 37 %, whereas 47 % was the highest DNA reassociation found between [P.] aerogenes and [P.] mairii. The study showed that [P.] aerogenes, [P.] mairii and [A.] rossii can not be easily separated and may consequently be misidentified based on current knowledge of their phenotypic characteristics. In addition, these taxa are difficult to separate from other taxa of the Pasteurellaceae. A revised scheme for separation based upon phenotypic characters is suggested for the three species [P.] aerogenes emend., [P.] mairii emend. and [A.] rossii emend., with the respective type strains ATCC 27883T, NCTC 10699T and ATCC 27072T.
Resumo:
The understanding of lumbar spine pathologies made substantial progress at the turn of the twentieth century. The authors review the original publication of Otto Veraguth in 1929 reporting on the successful resection of a herniated lumbar disc, published exclusively in the German language. His early report is put into the historical context, and its impact on the understanding of pathologies of the intervertebral disc (IVD) is estimated. The Swiss surgeon and Nobel Prize laureate Emil Theodor Kocher was among the first physicians to describe the traumatic rupture of the IVD in 1896. As early as 1909 Oppenheim and Krause published 2 case reports on surgery for a herniated lumbar disc. Goldthwait was the first physician to delineate the etiopathogenes is between annulus rupture, symptoms of sciatica, and neurological signs in his publication of 1911. Further publications by Middleton and Teacher in 1911 and Schmorl in 1929 added to the understanding of lumbar spinal pathologies. In 1929, the Swiss neurologist Veraguth (surgery performed by Hans Brun) and the American neurosurgeon Walter Edward Dandy both published their early experiences with the surgical therapy of a herniated lumbar disc. Veraguth's contribution, however, has not been appreciated internationally to date. The causal relationship between lumbar disc pathology and sciatica remained uncertain for some years to come. The causal relationship was not confirmed until Mixter and Barr's landmark paper in 1934 describing the association of sciatica and lumbar disc herniation, after which the surgical treatment became increasingly popular. Veraguth was among the first physicians to report on the clinical course of a patient with successful resection of a herniated lumbar disc. His observations should be acknowledged in view of the limited experience and literature on this ailment at that time.