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This tutorial reviewdiscusses synthetic strategies towards aromatic belts, defined here as double-stranded conjugated macrocycles, such as [n]cyclacenes, [n]cyclophenacenes, Schlüter belt, and Vögtle belt. Their appeal stems, firstly, from the unique nature of their conjugation, having p orbitals oriented radiallyrather than perpendicular to the plane of the macrocycle. Secondly, as aromatic belts are model compounds of carbon nanotubes of different chiralities, a synthetic strategy towards the buildup of structural strain in these compounds could finally open a route towards rational chemical synthesis of carbon nanotubes. The elusiveness of these compounds has stimulated fascinating and ingenious synthetic strategies over the last decades. The various strategies are classified here by their approach to the buildup of structural strain, which is the main obstacle in the preparation of these curved polyarenes. [ABSTRACT FROM AUTHOR]

STUDY DESIGN.: A randomized controlled trial. OBJECTIVE.: To investigate the effectiveness and cost of usual care plus patient choice of acupuncture, chiropractic, or massage therapy (choice) compared with usual care alone in patients with acute low back pain (LBP). SUMMARY OF BACKGROUND DATA.: Few studies have evaluated care models with facilitated access to and financial coverage for adjunctive complementary and alternative medicine therapies. METHODS.: A total of 444 patients with acute LBP (<21 days) were recruited from 4 clinical sites and randomized into 2 groups: usual care or choice. Outcomes included symptoms (bothersomeness), functional status (Roland), and satisfaction between baseline and 5 weeks, and cost of medical care in the 12 weeks after randomization. RESULTS.: After 5 weeks, providing patients with a choice did not yield clinically important reductions in symptoms (median −4, [interquartile range −7, −2] for usual care, and −5 [−7, −3] for choice; P = 0.002) or improvements in functional status (−8 [−13, −2] for usual care, and −9 [−15, −4] for choice; P = 0.15). Although there was a significantly greater satisfaction with care in the choice group, this came at a net increase in costs of $244 per patient. This consisted of a $99 reduction in the average cost to the insurer for medical care but an additional cost of $343, for an average of 6.0 complementary and alternative medicine treatments per patient. CONCLUSIONS.: A model of care that offered access to a choice of complementary and alternative medicine therapies for acute LBP did not result in clinically significant improvements in symptom relief or functional restoration. This model was associated with greater patient satisfaction but increased total costs. Future evaluations of this choice model should focus on patients with chronic conditions (including chronic back pain) for which conventional medical care is often costly and of limited benefit. [ABSTRACT FROM AUTHOR]

Pantothenate synthetase (PS) from Mycobacterium tuberculosis represents a potential target for antituberculosis drugs. PS catalyzes the ATP-dependent condensation of pantoate and β-alanine to form pantothenate. Previously, we determined the crystal structure of PS from M. tuberculosis and its complexes with AMPCPP, pantoate, and pantoyl adenylate. Here, we describe the crystal structure of this enzyme complexed with AMP and its last substrate, β-alanine, and show that the phosphate group of AMP serves as an anchor for the binding of β-alanine. This structure confirms that binding of β-alanine in the active site cavity can occur only after formation of the pantoyl adenylate intermediate. A new crystal form was also obtained; it displays the flexible wall of the active site cavity in a conformation incapable of binding pantoate. Soaking of this crystal form with ATP and pantoate gives a fully occupied complex of PS with ATP. Crystal structures of these complexes with substrates, the reaction intermediate, and the reaction product AMP provide a step-by-step view of the PS-catalyzed reaction. A detailed reaction mechanism and its implications for inhibitor design are discussed. [ABSTRACT FROM AUTHOR]

Summary: The MiSink Plugin converts Cytoscape, an open-source bioinformatics platform for network visualization, to a graphical interface for the database of interacting proteins (DIP: http://dip.doe-mbi.ucla.edu). Seamless integration is possible by providing bi-directional communication between Cytoscape and any Web site supplying data in XML or tab-delimited format. Availability: MiSink is freely available for download at http://dip.doe-mbi.ucla.edu/Software.cgi Contact: lukasz@mbi.ucla.edu [ABSTRACT FROM AUTHOR]

Background: An effective proficiency testing program must utilize accurate splitting procedures to ensure that customers receive equivalent (by some measure) test items. When test items are not equivalent, it becomes impossible to separate variation among laboratories from variation among test items, and the program cannot achieve its objectives. Therefore, there is a critical need to validate the splitting process used to manufacture test items. Objective: The incorporation of MicrotracersTM was investigated for validating the splitting process used in the Association of American Feed Control Officials Proficiency Testing Program and as a potential quality control event for a production run. Methods: Microtracers were incorporated into six production runs. From each run, 12 test items were randomly selected for evaluation. Proficiency test materials were prepared from commercially available feedstuffs using base animal feeds and feed additives. The tracers were incorporated into base feed with other additives, recovered, and counted from the randomly selected test items. Results: Uniformity of test items was evaluated with the following two statistical methods: (1) relative standard deviation (RSD) of particle counts according to a Poisson distribution and (2) a Pearson’s Chi-square test. RSDs for counts (per mass basis) ranged from 2.49 to 4.13%, and Chi-square P values ranged from 0.0097 to 0.3740 over the six sets. Conclusions: Microtracers were determined to be a potential tool for validating the splitting process used to manufacture proficiency test items and a tool for incorporating quality control events into the manufacture of proficiency test items. Highlights: The authors offer suggestions for proficiency testing programs [ABSTRACT FROM AUTHOR]

Abstract  Colonoscopy is a common procedure with the rare complication of a splenic injury. The proposed mechanism of injury is excessive splenocolic ligament traction. The diagnosis is made by computed tomography and the treatment is determined by the patient’s stability. Here we report a case of splenic injury during colonoscopy with failure to manage conservatively. A review of the literature and suggested guidelines are also provided. [ABSTRACT FROM AUTHOR]