FtsZ-independent septal recruitment and function of cell wall remodelling enzymes in chlamydial pathogens.

The nature and assembly of the chlamydial division septum is poorly defined due to the paucity of a detectable peptidoglycan (PG)-based cell wall, the inhibition of constriction by penicillin and the presence of coding sequences for cell wall precursor and remodelling enzymes in the reduced chlamydial (pan-)genome. Here we show that the chlamydial amidase (AmiA) is active and remodels PG in Escherichia coli. Moreover, forward genetics using an E. coli amidase mutant as entry point reveals that the chlamydial LysM-domain protein NlpD is active in an E. coli reporter strain for PG endopeptidase activity (ΔnlpI). Immunolocalization unveils NlpD as the first septal (cell-wall-binding) protein in Chlamydiae and we show that its septal sequestration depends on prior cell wall synthesis. Since AmiA assembles into peripheral clusters, trimming of a PG-like polymer or precursors occurs throughout the chlamydial envelope, while NlpD targets PG-like peptide crosslinks at the chlamydial septum during constriction.

Reference intervals for common carotid intima-media thickness measured with echotracking: relation with risk factors.

AIMS: Common carotid artery intima-media thickness (CCIMT) is widely used as a surrogate marker of atherosclerosis, given its predictive association with cardiovascular disease (CVD). The interpretation of CCIMT values has been hampered by the absence of reference values, however. We therefore aimed to establish reference intervals of CCIMT, obtained using the probably most accurate method at present (i.e. echotracking), to help interpretation of these measures. METHODS AND RESULTS: We combined CCIMT data obtained by echotracking on 24 871 individuals (53% men; age range 15-101 years) from 24 research centres worldwide. Individuals without CVD, cardiovascular risk factors (CV-RFs), and BP-, lipid-, and/or glucose-lowering medication constituted a healthy sub-population (n = 4234) used to establish sex-specific equations for percentiles of CCIMT across age. With these equations, we generated CCIMT Z-scores in different reference sub-populations, thereby allowing for a standardized comparison between observed and predicted ('normal') values from individuals of the same age and sex. In the sub-population without CVD and treatment (n = 14 609), and in men and women, respectively, CCIMT Z-scores were independently associated with systolic blood pressure [standardized βs 0.19 (95% CI: 0.16-0.22) and 0.18 (0.15-0.21)], smoking [0.25 (0.19-0.31) and 0.11 (0.04-0.18)], diabetes [0.19 (0.05-0.33) and 0.19 (0.02-0.36)], total-to-HDL cholesterol ratio [0.07 (0.04-0.10) and 0.05 (0.02-0.09)], and body mass index [0.14 (0.12-0.17) and 0.07 (0.04-0.10)]. CONCLUSION: We estimated age- and sex-specific percentiles of CCIMT in a healthy population and assessed the association of CV-RFs with CCIMT Z-scores, which enables comparison of IMT values for (patient) groups with different cardiovascular risk profiles, helping interpretation of such measures obtained both in research and clinical settings.

Chest wall syndrome among primary care patients: a cohort study.

BACKGROUND: The epidemiology of chest pain differs strongly between outpatient and emergency settings. In general practice, the most frequent cause is the chest wall pain. However, there is a lack of information about the characteristics of this syndrome. The aims of the study are to describe the clinical aspects of chest wall syndrome (CWS). METHODS: Prospective, observational, cohort study of patients attending 58 private practices over a five-week period from March to May 2001 with undifferentiated chest pain. During a one-year follow-up, questionnaires including detailed history and physical exam, were filled out at initial consultation, 3 and 12 months. The outcomes were: clinical characteristics associated with the CWS diagnosis and clinical evolution of the syndrome. RESULTS: Among 24 620 consultations, we observed 672 cases of chest pain and 300 (44.6%) patients had a diagnosis of chest wall syndrome. It affected all ages with a sex ratio of 1:1. History and sensibility to palpation were the keys for diagnosis. Pain was generally moderate, well localised, continuous or intermittent over a number of hours to days or weeks, and amplified by position or movement. The pain however, may be acute. Eighty-eight patients were affected at several painful sites, and 210 patients at a single site, most frequently in the midline or a left-sided site. Pain was a cause of anxiety and cardiac concern, especially when acute. CWS coexisted with coronary disease in 19 and neoplasm in 6. Outcome at one year was favourable even though CWS recurred in half of patients. CONCLUSION: CWS is common and benign, but leads to anxiety and recurred frequently. Because the majority of chest wall pain is left-sided, the possibility of coexistence with coronary disease needs careful consideration.

Survival and Sensemaking: Organizational Resilience in a Wall Street Trading Room After 9/11

How do organizations cope with extreme uncertainty? The existing literature is divided on this issue: some argue that organizations deal best with uncertainty in the environment by reproducing it in the organization, whereas others contend that the orga nization should be protected from the environment. In this paper we study the case of a Wall Street investment bank that lost its entire office and trading technology in the terrorist attack of September 11 th. The traders survived, but were forced to relocate to a makeshift trading room in New Jersey. During the six months the traders spent outside New York City, they had to deal with fears and insecurities inside the company as well as outside it: anxiety about additional attacks, questions of professional identity, doubts about the future of the firm, and ambiguities about the future re-location of the trading room. The firm overcame these uncertainties by protecting the traders' identities and their ability to engage in sensemaking. The organization held together through a leadership style that managed ambiguities and created the conditions for new solutions to emerge.

Cartilage thickness at the posterior medial femoral condyle is increased in femorotibial knee osteoarthritis: a cross-sectional CT arthrography study (Part 2).

OBJECTIVE: To evaluate the thickness of cartilage at the posterior aspect of the medial and lateral condyle in Osteoarthritis (OA) knees compared to non-OA knees using computed tomography arthrography (CTA). DESIGN: 535 consecutive knee CTAs (mean patient age = 48.7 ± 16.0; 286 males), were retrospectively analyzed. Knees were radiographically classified into OA or non-OA knees according to a modified Kellgren/Lawrence (K/L) grading scheme. Cartilage thickness at the posterior aspect of the medial and lateral femoral condyles was measured on sagittal reformations, and compared between matched OA and non-OA knees in the whole sample population and in subgroups defined by gender and age. RESULTS: The cartilage of the posterior aspect of medial condyle was statistically significantly thicker in OA knees (2.43 mm (95% confidence interval (CI) = 2.36, 2.51)) compared to non-OA knees (2.13 mm (95%CI = 2.02, 2.17)) in the entire sample population (P < 0.001), as well as for all subgroups of patients over 40 years old (all P ≤ 0.01), except for females above 60 years old (P = 0.07). Increase in cartilage thickness at the posterior aspect of the medial condyle was associated with increasing K/L grade in the entire sample population, as well as for males and females separately (regression coefficient = 0.10-0.12, all P < 0.001). For the lateral condyle, there was no statistically significant association between cartilage thickness and OA (either presence of OA or K/L grade). CONCLUSIONS: Cartilage thickness at the non-weight-bearing posterior aspect of the medial condyle, but not of the lateral condyle, was increased in OA knees compared to non-OA knees. Furthermore, cartilage thickness at the posterior aspect of the medial condyle increased with increasing K/L grade.

Transmission Fourier transform infrared microspectroscopy allows simultaneous assessment of cutin and cell-wall polysaccharides of Arabidopsis petals.

A procedure for the simultaneous analysis of cell-wall polysaccharides, amides and aliphatic polyesters by transmission Fourier transform infrared microspectroscopy (FTIR) has been established for Arabidopsis petals. The combination of FTIR imaging with spectra derivatization revealed that petals, in contrast to other organs, have a characteristic chemical zoning with high amount of aliphatic compounds and esters in the lamina and of polysaccharides in the stalk of the petal. The hinge region of petals was particular rich in amides as well as in vibrations potentially associated with hemicellulose. In addition, a number of other distribution patterns have been identified. Analyses of mutants in cutin deposition confirmed that vibrations of aliphatic compounds and esters present in the lamina were largely associated with the cuticular polyester. Calculation of spectrotypes, including the standard deviation of intensities, allowed detailed comparison of the spectral features of various mutants. The spectrotypes not only revealed differences in the amount of polyesters in cutin mutants, but also changes in other compound classes. For example, in addition to the expected strong deficiencies in polyester content, the long-chain acyl CoA synthase 2 mutant showed increased intensities of vibrations in a wavelength range that is typical for polysaccharides. Identical spectral features were observed in quasimodo2, a cell-wall mutant of Arabidopsis with a defect in pectin formation that exhibits increased cellulose synthase activity. FTIR thus proved to be a convenient method for the identification and characterization of mutants affected in the deposition of cutin in petals.

Ecologies of Value in a Wall Street Trading Room

Our task in this paper is to analyze the organization of trading in the era of quantitative finance. To do so, we conduct an ethnography of arbitrage, the trading strategy that best exemplifies finance in the wake of the quantitative revolution. In contrast to value and momentum investing, we argue, arbitrage involves an art of association-the construction of equivalence (comparability) of properties across different assets. In place of essential or relational characteristics, the peculiar valuation that takes place in arbitrage is based on an operation that makes something the measure of something else-associating securities to each other. The process of recognizing opportunities and the practices of making novel associations are shaped by the specific socio-spatial and socio-technical configurations of the trading room. Calculation is distributed across persons and instruments as the trading room organizes interaction among diverse principles of valuation.

Audit report on the City of Wall Lake, Iowa for the year ended June 30, 2006.

Audit report on the City of Wall Lake, Iowa for the year ended June 30, 2006.

Initial experiences with in vivo right coronary artery human MR vessel wall imaging at 3 tesla.

Due to their relatively small size and central location within the thorax, improvement in signal-to-noise (SNR) is of paramount importance for in vivo coronary vessel wall imaging. Thus, with higher field strengths, coronary vessel wall imaging is likely to benefit from the expected "near linear" proportional gain in SNR. In this study, we demonstrate the feasibility of in vivo human high field (3 T) coronary vessel wall imaging using a free-breathing black blood fast gradient echo technique with respiratory navigator gating and real-time motion correction. With the broader availability of more SNR efficient fast spin echo and spiral techniques, further improvements can be expected.

How to recognize opportunities: Heterarchical search in a Wall Street trading room

Our task in this paper is to analyze the organization of trading in the era of quantitativefinance. To do so, we conduct an ethnography of arbitrage, the trading strategy that bestexemplifies finance in the wake of the quantitative revolution. In contrast to value andmomentum investing, we argue, arbitrage involves an art of association - the constructionof equivalence (comparability) of properties across different assets. In place of essentialor relationa l characteristics, the peculiar valuation that takes place in arbitrage is based on an operation that makes something the measure of something else - associating securities to each other. The process of recognizing opportunities and the practices of making novel associations are shaped by the specific socio-spatial and socio-technical configurations of the trading room. Calculation is distributed across persons and instruments as the trading room organizes interaction among diverse principles of valuation.

Long-term treatment of eosinophilic esophagitis esophagitis with budesonide

BACKGROUND: Eosinophilic esophagitis (EoE) is a chronic-inflammatory disease of the esophagus, characterized by esophagus-related symptoms and a dense tissue eosinophilia, both refractory to proton pump inhibitors. Topical corticosteroids have proven effective in inducing clinical and histologic remission. However, a long-term strategy for the management of this chronic disease is not yet defined. METHODS: In a randomized, double-blind, placebocontrolled, long-term trial, we evaluated the efficacy of twice-daily 0.25 mg swallowed budesonide in maintaining a remission in adult EoE with prior response to induction therapy. Pre- and post-treatment disease activity was assessed clinically, endoscopically, histologically, by immunofluorescence and by high-resolution endosonography. The primary end point was the ability to maintain histologic remission (<5 eos/hpf) of EoE in. Secondary end points were the efficacy on symptom control and on tissue remodeling as well as the determination of the safety of long-term esophageal administration of topical corticosteroids. RESULTS: During a 50-week therapy of quiescent EoE with low-dose budesonide the esophageal eosinophil load (ECP staining) increased from 1.1 to 29.9 eos/hpf, but under placebo the increase was significantly larger (0.5 to 51.1 eos/hpf; p=0.01). At the end of the studyperiod, 35.7% (5/14) of the budesonide patients were in complete and 14.3% (2/14) in partial histologic remission; with placebo no patient was in complete and 28.6% (4/14) were in partial remission (p=0.0647). The increase of the symptom score was markedly lower in budesonide- (0.79 to 2.29 points) than in placebo-patients (0.71 to 4.00 points; p=0.0875). The median time to relapse of symptoms was >125 days in the budesonide and 95 days in the placebo group (p = 0.14). Measured by high-resolution endosonography, all EoE patients had pre-treatment a highly thickened esophageal wall compared with healthy controls (3.05±1.08 mm vs. 2.18±0.35 mm; p<0.0001). Long-term topical budesonide reduced mainly the thickness of the superficial wall layers (mucosa, 0.75 mm to 0.45 mm; p=0.025) whereas the response of the deeper layers was less pronounced (submucosa 1.31 to 1.08 mm; p=0.19 and muscularis 0.82 to 0.76 mm; p=0.72). Budesonide did not evoke any mucosal atrophy. CONCLUSIONS: This study clearly demonstrates that 1) Untreated eosinophil inflammation results in an impressive remodeling of the esophagus; 2) A therapy is therefore needed; 3) The high relapse rate after short-term therapy requires a long-term management and 4) Maintenance treatment with budesonide is well tolerated and keeps half of the patients in remission.

Artifact-free coronary magnetic resonance angiography and coronary vessel wall imaging in the presence of a new, metallic, coronary magnetic resonance imaging stent.

BACKGROUND: Coronary in-stent restenosis cannot be directly assessed by magnetic resonance angiography (MRA) because of the local signal void of currently used stainless steel stents. The aim of this study was to investigate the potential of a new, dedicated, coronary MR imaging (MRI) stent for artifact-free, coronary MRA and in-stent lumen and vessel wall visualization. METHODS AND RESULTS: Fifteen prototype stents were deployed in coronary arteries of 15 healthy swine and investigated with a double-oblique, navigator-gated, free-breathing, T2-prepared, 3D cartesian gradient-echo sequence; a T2-prepared, 3D spiral gradient-echo sequence; and a T2-prepared, 3D steady-state, free-precession coronary MRA sequence. Furthermore, black-blood vessel wall imaging by a dual-inversion-recovery, turbo spin-echo sequence was performed. Artifacts of the stented vessel segment and signal intensities of the coronary vessel lumen inside and outside the stent were assessed. With all investigated sequences, the vessel lumen and wall could be visualized without artifacts, including the stented vessel segment. No signal intensity alterations inside the stent when compared with the vessel lumen outside the stent were found. CONCLUSIONS: The new, coronary MRI stent allows for completely artifact-free coronary MRA and vessel wall imaging.