Modification of the cladinose C-4″ position via manipulation of the corresponding keto derivatives afforded two stereochemically pure series of compounds. The synthesis and structure determination of ...these compounds is described within. The in vitro and in vivo biological activity of this novel series of C-4″ modified macrolides is also described.
Novel C-4″ modified macrocyclic antibiotics with potent in vitro activity against
Pasteurella multocida and
Escherichia coli strains of bacteria are described.
Aryl and hetero aryl substituted 3,6-ketals of 15-membered azalide analogues were synthesized and were found to have potent in vitro antibacterial activity against veterinary pathogens, including
...Staphylococcus aureus and
Pasteurella multocida.
Aryl and hetero aryl substituted 3,6-ketals of 15-membered azalide analogues were synthesized and were found to have potent in vitro antibacterial activity against veterinary pathogens, including
Staphylococcus aureus and
Pasteurella multocida.
3,6-Ketals of 15-membered azalide pseudoaglycones are a novel series of macrolide antibiotics. The aromatic derivatives of the azalide 3,6-ketals demonstrated potent antibacterial activities against ...both Gram-positive and Gram-negative bacteria.
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Drugs can cause long-QTc-syndrome (LQTS), thereby elevating the risk for palpitations, syncopes, and sudden cardiac death. Additional risk factors such as the intake of more than one QTc-prolongating ...drug (QTPD) and surgery (cardiac and non-cardiac) increase the risk considerably. Therefore, a good knowledge of patientś perioperative risk is important. Data concerning this issue in surgical patients is, however, scarce. We aimed to determine the number of surgical patients taking QTPD at hospital admission and to assess the presence of additional risk factors for LQTS. In addition, we determined the LQTS-risk at hospital admission by calculating the Tisdale Risk Score, enabling early detection of patients at risk. In a retrospective study, the pre-hospital medication of a 4-month cohort of surgical patients admitted to a tertiary teaching hospital was evaluated for QTPD-intake. For these patients, additional risk factors for LQTS were assessed and the Tisdale Risk Score was calculated. Of 837 surgical patients, 419 (50%) took at least one QTPD. In total, 3,376 drugs were taken and 723 (21%) classified as QTPD with a median number of 2 (range 1-8) per patient. The median number of LQTS-risk factors for these patients at hospital admission was 2 (range 0-5). The Tisdale Risk Score classified 23 patients (5%) as high, 187 (45%) as moderate, and 209 (50%) as low risk. These findings indicate a high number of surgical patients with QTPD and additional risk factors. The Tisdale Risk Score can be used as a screening instrument for patients at risk for QTc-prolongation during medication reconciliation by pharmacists at hospital admission. Patients identified as high and moderate risk should be evaluated for adjustable risk factors and monitored adequately. Medical treatment needs to be chosen carefully in view of in-hospital patient safety.
Atoms made of a particle and an antiparticle are unstable, usually surviving less than a microsecond. Antihydrogen, made entirely of antiparticles, is believed to be stable, and it is this longevity ...that holds the promise of precision studies of matter-antimatter symmetry. We have recently demonstrated trapping of antihydrogen atoms by releasing them after a confinement time of 172 ms. A critical question for future studies is: how long can anti-atoms be trapped? Here, we report the observation of anti-atom confinement for 1,000 s, extending our earlier results by nearly four orders of magnitude. Our calculations indicate that most of the trapped anti-atoms reach the ground state. Further, we report the first measurement of the energy distribution of trapped antihydrogen, which, coupled with detailed comparisons with simulations, provides a key tool for the systematic investigation of trapping dynamics. These advances open up a range of experimental possibilities, including precision studies of charge-parity-time reversal symmetry and cooling to temperatures where gravitational effects could become apparent. PUBLICATION ABSTRACT
Abstract
The CERN ALPHA experiment makes precision measurements of antihydrogen atoms, confined in a superconducting magnetic minimum trap. Recent measurements of the antihydrogen spectrum have ...already provided high-resolution tests of fundamental symmetries, and ALPHA has now embarked on an ambitious upgrade programme aimed at directly comparing hydrogen and antihydrogen within their existing atom trap. One aspect of this upgrade will be the development of a low-energy (50 eV) hydrogen ion source that is compatible with ALPHA’s existing magnetic charged particle beamlines. PELLIS, previously developed at JYFL, is a 5 keV filament-driven source that generates H
-
beams with low emittances and currents of up to 50
μ
A. Here, we explore the feasibility of a proposed electrostatic beamline design to transport H
-
ions from a PELLIS-type ion source into ALPHA’s various particle traps. We present SIMION simulations that were used to develop the beamline, focusing on components such as a quadrupole switchyard and drift tube deceleration stage.
Peptidoglycan (PGN) is ubiquitous in nearly all bacterial species. The PGN sacculus protects the cells against their own internal turgor making PGN one of the most important targets for antibacterial ...treatment. Within the last sixty years PGN composition has been intensively studied by various methods. The breakthrough was the application of HPLC technology on the analysis of muropeptides. However, preparation of pure PGN relied on a very time consuming method of about one week. We established a purification protocol for both Gram-positive and Gram-negative bacteria which can be completely performed in plastic reaction tubes yielding pure muropeptides within 24 hours. The muropeptides can be analyzed by UPLC-MS, allowing their immediate determination. This new rapid method provides the feasibility to screen PGN composition even in high throughput, making it a highly useful tool for basic research as well as for the pharmaceutical industry.
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