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Inelastic $\alpha$-particle scattering at energies of a few hundred MeV and very-forward scattering angles including $0^\circ$ has been established as a tool for the study of the isoscalar giant monopole (IS0) strength distributions in nuclei. An independent investigation of the IS0 strength in nuclei across a wide mass range was performed using the $0^\circ$ facility at iThemba Laboratory for Accelerator Based Sciences (iThemba LABS), South Africa, to understand differences observed between IS0 strength distributions in previous experiments performed at the Texas A\&M University (TAMU) Cyclotron Institute, USA and the Research Center for Nuclear Physics (RCNP), Japan. The isoscalar giant monopole resonance (ISGMR) was excited in $^{58}$Ni, $^{90}$Zr, $^{120}$Sn and $^{208}$Pb using $\alpha$-particle inelastic scattering with $196$ MeV $\alpha$ beam and scattering angles $\theta_{\text{Lab}} = 0^\circ$ and $4^\circ$. The K$600$ magnetic spectrometer at iThemba LABS was used to detect and momentum analyze the inelastically scattered $\alpha$ particles. The IS0 strength distributions in the nuclei studied were deduced with the difference-of-spectra (DoS) technique including a correction factor for the $4^\circ$ data based on the decomposition of $L > 0$ cross sections in previous experiments. IS0 strength distributions for $^{58}$Ni, $^{90}$Zr, $^{120}$Sn and $^{208}$Pb are extracted in the excitation-energy region $E_{\rm x} = 9 - 25$ MeV.Using correction factors extracted from the RCNP experiments, there is a fair agreement with their published IS0 results. Good agreement for IS0 strength in $^{58}$Ni is also obtained with correction factors deduced from the TAMU results, while marked differences are found for $^{90}$Zr and $^{208}$Pb., Comment: 12 pages, 10 figures, regular article submitted to PRC

The present study evaluated the in vitro potency of ceftazidime and cefepime among carbapenem-resistant Pseudomonas aeruginosa isolates collected as part of a global surveillance program and assessed the pharmacodynamic implications using previously published population pharmacokinetics. When susceptible, MICs resulted at the high end of distribution for both ceftazidime and cefepime, thus 6 g/day was required to achieve optimal pharmacodynamic profiles. These findings should be considered in the clinic and for the application of CLSI susceptibility breakpoints.

The present study evaluated the in vitro potency of ceftazidime and cefepime among carbapenem-resistant Pseudomonas aeruginosa isolates collected as part of a global surveillance program and assessed the pharmacodynamic implications using previously published population pharmacokinetics. When susceptible, MICs resulted at the high end of distribution for both ceftazidime and cefepime, thus 6 g/day was required to achieve optimal pharmacodynamic profiles. These findings should be considered in the clinic and for the application of CLSI susceptibility breakpoints. © 2021 American Society for Microbiology.

Background. Klebsiella pneumoniae is an opportunistic pathogen often associated with nosocomial infections. A suspected outbreak of K. pneumoniae isolates, exhibiting reduced susceptibility to carbapenem antibiotics, was detected during the month of May 2012 among patients admitted to a haematology unit of a tertiary academic hospital in Cape Town, South Africa (SA).Objectives. An investigation was done to determine possible epidemiological links between the case patients and to describe the mechanisms of carbapenem resistance of these bacterial isolates.Methods. Relevant demographic, clinical and laboratory information was extracted from hospital records and an observational review of infection prevention and control practices in the affected unit was performed. Antimicrobial susceptibility testing including phenotypic testing and genotypic detection of the most commonly described carbapenemase genes was done. The phylogenetic relationship of all isolates containing the blaOXA-181 carbapenemase gene was determined by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing.Results. Polymerase chain reaction analysis identified a total of seven blaOXA-181-positive, carbapenem-resistant K. pneumoniae isolates obtained from seven patients, all from a single unit. These isolates were indistinguishable using PFGE analysis and belonged to sequence type ST-14. No other carbapenemase enzymes were detected.Conclusion. This is the first documented laboratory-confirmed outbreak of OXA-181-producing K. pneumoniae in SA, and highlights the importance of enforcing strict adherence to infection control procedures and the need for ongoing surveillance of antibiotic-resistant pathogens in local hospitals.