A chemoselective and continuous synthesis of m-sulfamoylbenzamide analogues

For the synthesis of m-sulfamoylbenzamide analogues, small molecules which are known for their bioactivity, a chemoselective procedure has been developed starting from m-(chlorosulfonyl) benzoyl chloride. Although a chemoselective process in batch was already reported, a continuous-flow process reveals an increased selectivity at higher temperatures and without catalysts. In total, 15 analogues were synthesized, using similar conditions, with yields ranging between 65 and 99%. This is the first automated and chemoselective synthesis of m- sulfamoylbenzamide analogues

Point Defects in Crystals of Charged Colloids

Charged colloidal particles - both on the nano and micron scales - have been instrumental in enhancing our understanding of both atomic and colloidal crystals. These systems can be straightforwardly realized in the lab, and tuned to self-assemble into body-centered cubic (BCC) and face-centered cubic (FCC) crystals. While these crystals will always exhibit a finite number of point defects, including vacancies and interstitials - which can dramatically impact their material properties - their existence is usually ignored in scientific studies. Here, we use computer simulations and free-energy calculations to characterize vacancies and interstitials in both FCC and BCC crystals of point-Yukawa particles. We show that, in the BCC phase, defects are surprisingly more common than in the FCC phase, and the interstitials manifest as so-called crowdions: an exotic one-dimensional defect proposed to exist in atomic BCC crystals. Our results open the door to directly observing these elusive defects in the lab.Comment: 8 pages, 4 figure

Brucellosis serology as an alternative diagnostic test for patients with malaria-like symptoms

Background: In a low transmission zone for malaria, we explored the presence of brucellosis as an alternative diagnosis in febrile patients. Specifically, the objective of our study was to determine the proportion of patients presenting to the hospital with malaria-like febrile symptoms that were concurrently brucellosis sero-positive, and assess related risk factors.Methods: The study was done at the rural hospital in Endulen, in the Ngorongoro Conservation Area (NCA), Tanzania. Hospital patients were enrolled showing malaria-like febrile symptoms and were tested for malaria (microscopy) as well as brucellosis (agglutination test, plus commercial ELISAs for IgM and for IgG). Patient demographic characteristics and risk factors for brucellosis were determined using a questionnaire interview.Results: A total of 159 patients were enrolled, of which 57 were positive for malaria and 58 were positive by ELISA for brucellosis, with 54 (93%) of these brucellosis-positives solely positive for isotype IgG, 1 (1.7%) solely for isotype IgM, and 3 (5.2%) positive for both IgM and IgG. However, the brucellosis agglutination test was only positive in 9 of 159 samples. Co-infections of malaria and brucellosis occurred, but malaria disease status was not significantly correlated with brucellosis status. Patients serologically positive for brucellosis were more likely to have had contact with aborted animal materials (p=0.002).Conclusions: Brucellosis is a potentially missed diagnosis amongst pastoralists in rural Tanzania with malaria-like symptoms. However, concurrent and isotope-specific serology is integral to ensure detection and appropriate clinical management.  

Applicability and accuracy of an intraoral scanner for scanning multiple implants in edentulous mandibles:A pilot study

Statement of problem. In the past 5 years, the use of intraoral digitizers has increased. However, data are lacking on the accuracy of scanning implant restorative platforms for prosthodontics with intraoral digitizers. Purpose. The purpose of this clinical pilot study was to assess the applicability and accuracy of intraoral scans by using abutments designed for scanning (scan abutments) in edentulous mandibles. Material and methods. Twenty-five participants with complete mandibular overdentures retained by 2 implants and frameworks were included in this study. Scan abutments were placed on the implants intraorally and scanned with the iTero intraoral scanner. Also, scan abutments were placed on the implant analogs of the definitive casts and scanned with an extraoral laboratory scanner (Lava Scan ST scanner). Two 3-dimensional computer-aided design models of the scan abutments with predetermined center lines were subsequently imported and registered, together with each of the scanned equivalents. The distance between the centers of the top of the scan abutments and the angulations between the scan abutments was assessed. These values were compared with the measurements made on the 3-dimensional scans ofthe definitive casts, which were the participants' original definitive casts used for fabrication of soldered bars. The threshold for distance error was established to be 100 mu m. Results. Four of the 25 intraoral scans were not suitable for research because the intraoral scanner was not able to stitch the separate scans together. Five of the 21 suitable scans demonstrated an interimplant distance error >100 Rm. Three of the 25 intraoral scans showed interimplant angulation errors >0.4 degrees. Only 1 scan showed both an acceptable interimplant distance ( Conclusions. Based on the intraoral scans obtained in this study, distance and angulation errors were too large to fabricate well-fitting frameworks on implants in edentulous mandibles. The main reason for the unreliable scans seemed to be the lack of anatomic landmarks for scanning