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Over a 17-year period, 92 patients with esophageal disease underwent colon interposition or bypass, with each operation performed by the same surgeon. The indication was cure of cancer in 20 patients, relief of dysphagia in 55 (cancer in 17 patients and benign in 38), loss of gastrointestinal (G.I.) continuity in ten, and tracheoesophageal fistula in seven patients (malignant in five, benign in 2). The thirty-day operative mortality rate was 5%, and the hospital mortality rate was 9%. Graft necrosis occurred in seven of 92 patients, four of whom later underwent a successful second reconstruction. Thirteen patients required subsequent revisional surgery. In 85 patients, the left colon based on the inferior mesenteric artery was used, and in seven, the right colon was used. Technical insights were gained to help preserve the blood supply to the graft and improve its function in transporting food. Thirty-four patients were available for interview 2-17 years after operation (median of 5 years) 28 of whom had benign disease, and six of whom had malignant disease); 82% of the patients felt they were cured of their preoperative symptoms, 18% improved, and none worsened. Eighty-eight per cent of the patients were able to receive an unrestricted diet. All patients except one were satisfied with the results of surgery, and, asked what they would do if they had to make the choice again, all responded that they would have the operation. Twenty-six of the interviewed patients had their eating ability evaluated with a test meal and the transit time of a liquid and solid barium bolus measured. Compared to controls, patients with colon interpositions consumed a smaller capacity meal over a longer period of time and were not dependent on liquids to flush the food through the colon graft. A colon interposition provides good quality of deglutition, is very durable, and is the organ of choice for patients who require an esophageal substitute and are potential candidates for long survival.

Mycoplasma mycoides subsp. mycoidesSC (MmymySC)is the etiological agent of contagious bovine pleuropneumonia (CBPP), a highly contagious respiratory disease in cattle. The genome of Mmymy SC type strain PG1T has been sequenced to map all the genes and to facilitate further studies regarding the cell function of the organism and CBPP. The genome is characterized by a single circular chromosome of 1,211,703 bp with the lowest G+C content (24 mole%)and the highest density of insertion sequences (13% of the genome size)of all sequenced bacterial genomes. The genome contains 985 putative genes, of which 72 are part of insertion sequences and encode transposases. Anomalies in the GC-skew pattern and the presence of large repetitive sequences indicate a high genomic plasticity. A variety of potential virulence factors was identified, including genes encoding putative variable surface proteins and enzymes and transport proteins responsible for the production of hydrogen peroxide and the capsule, which is believed to have toxic effects on the animal.

The so-called Mycoplasma mycoides cluster consists of six species or subspecies of mycoplasmas (Mollicutes). These species are pathogenic for ruminants and some of them are of great concern in veterinary medicine. The members of the M. mycoides cluster have two rRNA operons (rrnA and rrnB). The nucleotide sequences of the 16S rRNA genes of 10 strains, representing all of the known species and subspecies of the M. mycoides cluster, were determined by direct automated solid-phase DNA sequencing. The sequences of both rRNA operons were determined by a novel strategy involving in vitro amplification by PCR with one operon-specific primer pair and one general primer pair. Interestingly, sequence differences (polymorphisms) between the two operons were observed for all strains. Two strains of M. capricolum subsp. capripneumoniae were sequenced, and 15 polymorphisms were found in the type strain (F38) and 17 polymorphisms were found in the other strain (4/2LC). Eight polymorphisms were found in the 16S rRNA genes of the M. mycoides subsp. mycoides smallcolony type, and sequence length variations in a poly(A) region were observed in the 16S rRNA genes of the two operons of this species. Secondary-structure analysis showed that polymorphisms were present in both stem and loop regions. The nucleotide substitutions in the polymorphic sites of the stem regions often resulted in a change from a canonical to a noncanonical base pairing or vice versa. A compensatory mutation was never observed in the other nucleotide of the base pair. Phylogenetic analysis based on the 16S rRNA sequences indicated that Mycoplasma sp. strain PG50 should be included in the M. capricolum species group. Furthermore, the 16S rRNA sequences of M. mycoides subsp. capri and the M. mycoides subsp. mycoides large-colony type were 99.9% identical. We therefore suggest that these species be reclassified in a common species group (for instance, "Mycoplasma capri") distinct from the M. mycoides subsp. mycoides small-colony type, which formed an intermediate branch between the M. capricolum species group and the M. capri species group.Many species belonging to the class Mollicutes (trivial name, mycoplasmas) are pathogenic and of great economic concern in livestock production. There is one interesting group of six closely related mycoplasmas named the Mycoplasma mycoides cluster, consisting of several ruminant pathogens (13,49,50). This group comprises the following species, subspecies, or strains: M. capricolum subsp. capricolum (formerly M. capricolum), M. capricolum subsp. capripneumoniae (formerly Mycoplasma sp. strain F38), M. mycoides subsp. capri, the M. mycoides subsp. mycoides large-colony (LC) and small-colony (SC) types, and Mycoplasma sp. strain PG50.The best-known species in the M. mycoides cluster is perhaps the M. mycoides subsp. mycoides SC type, which is the causative agent of contagious bovine pleuropneumonia. This disease has been known since the 18th century, and the organism was first isolated in 1898 by Nocard and Roux (38). The M. myco...

Almost complete (>96%) 16s rRNA sequences from nine ruminant mycoplasmas have been determined by solid-phase DNA sequencing. Polymorphisms were found in four of the 16s rRNA sequences, which indicated the existence of two different rRNA operons. Seven polymorphisms were found in Mycoplasma agalactiae, three were found in Mycoplasma bovis, one was found in Mycoplasma alkalescens, and one was found in Mycophinu bovirhinis. The sequence data were used for construction of phylogenetic trees. All but one of the ruminant mycoplasmas sequenced in this work clustered in the hominis group. A close relationship was found between M. agalactiae and M. bovis, with a 99% nucleotide similarity between their 16s rRNA sequences. They were also found to be members of the Mycoplasma lipophilum cluster of the hominis group. Furthermore, the 16s rRNA comparisons showed that Mycoplasma alkalescens and Mycoplasma canadense are closely related (>98.5%), and these species were found to cluster in the Mycoplasma hominis cluster of the hominis group. Interestingly, M. bovirhinis grouped in a new phylogenetic cluster of the hominis group. The new cluster, which was supported by bootstrap percentage values, signature nucleotide analysis, and higher-order structural elements, was named the Mycoplasma synoviae cluster. Mycoplasma bovoculi, Mycoplasma conjunctivae, and Mycoplasma ovipneumoniae clustered in the Mycoplasma neurolyticum cluster of the hominis group. Mycoplasma alvi clustered with Mycoplasma pirum in the M. pneumoniae cluster of the pneumoniae group.Mycoplasmas (class Mollicutes) are among the smallest microorganisms capable of self-replication and autonomous life. About 150 species are known today, and they are closely related to gram-positive bacteria with a low G+C content in the genome (17). Many mycoplasmas are pathogenic for animals, and they are therefore of great concern in veterinary medicine (18,20). Most mycoplasmas are host specific, and ruminants harbor a number of interesting species. Two very important and closely related species are Mycoplasma bovis and Mycoplasma agalactiae. The former causes calf pneumonia, mastitis, and arthritis in cattle (3,21), and the latter species is the causal agent of contagious agalactia in goats and sheep (10). The other species used for 16s rRNA sequencing in this study are also of clinical significance, except Mycoplasma alvi. Mycoplasma alkalescens causes arthritis in cattle. M. alvi has no known disease-causing potential, but has been isolated from the respiratory tract of cattle. Mycoplasma bovirhinis is often isolated from cattle with respiratory disease, but is probably not a primary pathogen. Mycoplasma bovoculi is associated with conjunctivitis and keratoconjunctivitis in cattle and is often found in the eyes of calves. Mycoplasma canadense is believed to cause mastitis in cattle. Mycoplasma conjunctivae is the causal agent of keratoconjunctivitis in goats and sheep, but it is not clear whether it is a primary or a secondary pathogen. Mycoplasma ovipneumoniae is by far the mos...

Reflux is the predominant risk factor for BO, and proximal gastric colonization of H. pylori seems to amplify this risk.

The situation for governors and managers of natural resources has increased in complexity. Previously it was enough to sustain the yields of wood, food and energy. Today, maintenance of ecosystem services, conservation of biodiversity, rural development and human wellbeing are new additional objectives. At the same time there are new risks and uncertainties linked to climate change, economic globalisation, energy security and water supply. Consequently, adaptive and holistic research, governance and management are needed. Landscape is a concept and framework that can be used as an approach to enhance implementation of policies about sustainable development as a societal process and sustainability as outcomes on the ground. For our analysis to define the landscape approach we used a hierarchical framework consisting of principles, concepts and initiatives; and included three principles defining SD and sustainability and five international concepts to analyze its implementation for our analysis to define landscape approach. We propose a practical operationalization that consists of five core attributes, (1) a sufficiently large area that matches management requirements and challenges to deliver desired goods, services and values, (2) multi-level and multi-sector stakeholder collaboration that promotes sustainable development as a social process, (3) commitment to and understanding of sustainability as an aim among stakeholders, (4) integrative knowledge production, and (5) sharing of experience, results and information, to develop local or tacit to general or explicit knowledge. Finally, we discuss the need for integrative research to study landscape approach concepts and what local initiatives using different concepts deliver on the ground.