Host adapted serotypes of <i>Salmonella enterica</i>

Salmonella constitutes a genus of zoonotic bacteria of worldwide economic and health importance. The current view of salmonella taxonomy assigns the members of this genus to two species: S. enterica and S. bongori. S. enterica itself is divided into six subspecies, enterica, salamae, arizonae, diarizonae, indica, and houtenae, also known as subspecies I, II, IIIa, IIIb, IV, and VI, respectively. Members of Salmonella enterica subspecies enterica are mainly associated with warm-blooded vertebrates and are usually transmitted by ingestion of food or water contaminated by infected faeces. The pathogenicity of most of the distinct serotypes remains undefined, and even within the most common serotypes, many questions remain to be answered regarding the interactions between the organism and the infected host. Salmonellosis manifests itself in three major forms: enteritis, septicaemia, and abortion, each of which may be present singly or in combination, depending on both the serotype and the host involved. Although currently over 2300 serovars of Salmonella are recognized, only about 50 serotypes are isolated in any significant numbers as human or animal pathogens and they all belong to subspecies enterica. Of these, most cause acute gastroenteritis characterized by a short incubation period and a severe systemic disease in man or animals, characterized by septicaemia, fever and/or abortion, and such serotypes are often associated with one or few host species. It is the intention of this review to present a summary of current knowledge of these host-adapted serotypes of S. enterica. The taxonomic relationships between the serotypes will be discussed together with a comparison of the pathology and pathogenesis of the disease that they cause in their natural host(s). Since much of our knowledge on salmonellosis is based on the results of work on Typhimurium, this serotype will often be used as the baseline in discussion. It is hoped that an appreciation of the differences that exist in the way these serotypes interact with the host will lead to a greater understanding of the complex host–parasite relationship that characterizes salmonella infections

The N=1 supersymmetric bootstrap and Lie algebas

The bootstrap programme for finding exact S-matrices of integrable quantum field theories with N=1 supersymmetry is investigated. New solutions are found which have the same fusing data as bosonic theories related to the classical affine Lie algebras. When the states correspond to a spinor spot of the Dynkin diagram they are kinks which carry a non-zero topological charge. Using these results, the S-matrices of the supersymmetric O($2n$) sigma model and sine-Gordon model can be shown to close under the bootstrap.Comment: 21 pages, 3 figures (uses psfig.tex), plain tex with macro include

Contributors to the December Issue/Notes

Notes by Warren A. Deahl, W. J. Rafferty, Timothy M. Green, Bernard F. Grainey, and Jerome Gold

The Analytic Structure of Trigonometric S Matrices

$S$-matrices associated to the vector representations of the quantum groups for the classical Lie algebras are constructed. For the $a_{m-1}$ and $c_m$ algebras the complete $S$-matrix is found by an application of the bootstrap equations. It is shown that the simplest form for the $S$-matrix which generalizes that of the Gross-Neveu model is not consistent for the non-simply-laced algebras due to the existence of unexplained singularities on the physical strip. However, a form which generalizes the $S$-matrix of the principal chiral model is shown to be consistent via an argument which uses a novel application of the Coleman-Thun mechanism. The analysis also gives a correct description of the analytic structure of the $S$-matrix of the principle chiral model for $c_m$.Comment: 25 pages (macro included, 6 figures included as uuencoded compressed tar file), CERN-TH.6888/93, (An important argument is corrected leading to a novel application of the Coleman-Thun mechanism. Also decided to risk some figures.

Contributors to the December Issue/Notes

Notes by Warren A. Deahl, W. J. Rafferty, Timothy M. Green, Bernard F. Grainey, and Jerome Gold

Estimation of rate coefficients and branching ratios for gas-phase reactions of OH with aliphatic organic compounds for use in automated mechanism construction

Reaction with the hydroxyl (OH) radical is the dominant removal process for volatile organic compounds (VOCs) in the atmosphere. Rate coefficients for reactions of OH with VOCs are therefore essential parameters for chemical mechanisms used in chemistry transport models, and are required more generally for impact assessments involving the estimation of atmospheric lifetimes or oxidation rates for VOCs. Updated and extended structure–activity relationship (SAR) methods are presented for the reactions of OH with aliphatic organic compounds, with the reactions of aromatic organic compounds considered in a companion paper. The methods are optimized using a preferred set of data including reactions of OH with 489 aliphatic hydrocarbons and oxygenated organic compounds. In each case, the rate coefficient is defined in terms of a summation of partial rate coefficients for H abstraction or OH addition at each relevant site in the given organic compound, so that the attack distribution is defined. The information can therefore guide the representation of the OH reactions in the next generation of explicit detailed chemical mechanisms. Rules governing the representation of the subsequent reactions of the product radicals under tropospheric conditions are also summarized, specifically their reactions with O2 and competing processes

Validation of the English Language Pain Sensitivity Questionnaire

Background and Objectives: The Pain Sensitivity Questionnaire (PSQ) is predictive of pain-related responses to experimental stimuli in German-speaking individuals. Here, we explored the validation of the English translation of the PSQ (PSQ-E). Methods: One hundred thirty-six patients scheduled to undergo a low back interventional procedure completed the PSQ-E and other questionnaires including the Brief Pain Inventory. Pain ratings on a visual analog scale (VAS) were obtained following 2 standardized injections of subcutaneous lidocaine (VAS 1, infiltration in hand; VAS 2, infiltration of procedural site). The VAS measures were compared with the PSQ-E data and other inventories using linear regression analysis with stepwise selection of variables. Results: The PSQ-E properties were in all respects similar to those of the original German PSQ. VAS 1 magnitude was predicted by PSQ-E-minor (r = 0.26, P < 0.01). VAS 2 magnitude was predicted by PSQ-E-minor (r = 0.34, P < 0.001), and the prediction was significantly enhanced by further inclusion of the Brief Pain Inventory interference score (total r = 0.40, P < 0.001). Conclusions: The study demonstrated that a significant correlation exists between the PSQ-E and clinically relevant pain ratings. This study validates the PSQ-E both in terms of measuring pain sensitivity and as possible means of recognizing patients with high pain sensitivity. Defining this subset of patients may have clinical utility in the future

A fossil peat deposit from the Late Triassic (Carnian) of Zimbabwe with preserved cuticle of Pteridospermopsida and Ginkgoales, and its geological setting

Well-preserved cuticular material of Pteridospermopsida and Ginkgoales from the Late Triassic of Zimbabwe is described here for the first time. It is preserved within a brown peat-like lens in the Upper Karoo Angwa Sandstone Formation. The locality is on the Manyima River in the lower portion of the mid-Zambezi Valley of Zimbabwe. Using SEM and light microscopy to identify the taxa, the fragmentary cuticles are of Pteridospermopsida type and have been assigned to Lepidopteris sp. (Peltaspermales) and Dicroidium sp. A, B, (Corystospermales). Cuticles of the ginkgoalean leaf genus, Sphenobaiera, are also described. Well-preserved ovules were found in close association with the cuticles, but as the stomata are not visible they cannot be assigned to any genus. Based on their close similarity to the Dicroidium flora of the South African Upper Karoo, the plants are considered to be equivalent to the South African Molteno Formation in age (Carnian). The palynoflora supports this age bracket, as does fauna preserved nearby. The taphonomic process was one of transport, sorting and deposition in a fluvial system.The CNRS-NRF agreement between France and South Afric