Gera Kisselman - Academia.edu (original) (raw)

Papers by Gera Kisselman

Research paper thumbnail of research papers Acta Crystallographica Section D Biological

X-CHIP: an integrated platform for high-throughput protein crystallization and on-the-chip X-ray ... more X-CHIP: an integrated platform for high-throughput protein crystallization and on-the-chip X-ray diffraction data collection

Research paper thumbnail of protein PA0269 from Pseudomonas aeruginosa

Homology of the AhpD-like structural family

Research paper thumbnail of Echo Milestones: A Novel Simulation-Based Echocardiography Competence Tool for Formative Assessment in Cardiology Training

Journal of the American College of Cardiology, 2017

Background: There is a paradigm shift in cardiology education to competency-based approaches, whi... more Background: There is a paradigm shift in cardiology education to competency-based approaches, which promote skill development through self-regulated learning and multiple formative assessments. We propose a simulation-based echocardiography competence assessment tool (ECAT) in a large Canadian cardiology training program. Methods: Pilot study of cardiology trainees at the University of Toronto in 2016 (n=5 PGY4; n=5 PGY5; n=4 PGY³6). Trainees were oriented to the simulator, had 30 minutes to practice, and underwent ECAT testing. We video-recorded performance and acquired simulated echo videos. Four raters assessed performance in real-time or off-line; we assessed inter-rater reliability. We examined relationships between ECAT score and level of training, self-reported echos seen, performed and interpreted, diagnostic scan quality and end of year exam score. Trainees received video footage immediately, and rater feedback within 2 weeks. We interviewed trainees and rater about their ECAT experience. Results: ECAT score was positively associated with level of training (p=0.0056), previous echos seen (p=0.01), performed (p=0.01), and interpreted (p=0.02), and diagnostic quality of scan (p=0.0006). ECAT score correlated with end of year exam score (p=0.01). Intra-class correlation coefficient was 0.56 and Cronbach coefficient alpha was 0.94. Preliminary review of interview transcripts revealed three areas of discussion: 1) the clinical learning environment is variable, and the simulator offers an innovative, standardized setting to practice skills; 2) trainees, particularly novices, report receiving limited feedback, and valued opportunities to be coached; 3) trainees believed the feedback enhanced their learning and motivation, and requested additional opportunities for future learning. Conclusions: The ECAT process, feedback, and technology were highly valued by by millennial learners. The ECAT has high internal consistency, and scores correlate positively with trainees' clinical experience. While there is a need to improve inter-rater reliability, the validity evidence is promising for using ECAT to provide directions for skills development in echo training.

Research paper thumbnail of Identification of novel fragment-based hits forP. bergheiorotidine 5′-monophosphate decarboxylase

Acta Crystallographica Section A Foundations of Crystallography, 2008

For a quarter of a century the isolation of polymorph from III of paracetamol has been a problem ... more For a quarter of a century the isolation of polymorph from III of paracetamol has been a problem due to its instability. In 1997 P. Di Martino et al [1] published the first route to prepare form III of paracetamol but they were not able to observe an x-ray diffractogram from form III. Recently J.B. Burley et al [2] isolated the polymorphic form III, but they could not draw conclusions from the powder diffractogram due to the large non-crystalline fraction. In this paper we present x-ray powder diffraction data from paracetamol form III as well as data from forms II and I. Also data collected at non-ambient temperatures will be discussed. Lattice parameters and a structure for form III will be proposed on the basis of the collected x-ray powder diffraction data.

![Research paper thumbnail of The structure of SAV1646 fromStaphylococcus aureusbelonging to a new `ribosome-associated' subfamily of bacterial proteins](https://a.academia-assets.com/images/blank-paper.jpg)

Acta Crystallographica Section D Biological Crystallography, 2015

The crystal structure of the SAV1646 protein from the pathogenic microorganismStaphylococcus aure... more The crystal structure of the SAV1646 protein from the pathogenic microorganismStaphylococcus aureushas been determined at 1.7 Å resolution. The 106-amino-acid protein forms a two-layer sandwich with α/β topology. The protein molecules associate as dimers in the crystal and in solution, with the monomers related by a pseudo-twofold rotation axis. A sequence-homology search identified the protein as a member of a new subfamily of yet uncharacterized bacterial `ribosome-associated' proteins with at least 13 members to date. A detailed analysis of the crystal protein structure along with the genomic structure of the operon containing thesav1646gene allowed a tentative functional model of this protein to be proposed. The SAV1646 dimer is assumed to form a complex with ribosomal proteins L21 and L27 which could help to complete the assembly of the large subunit of the ribosome.

Research paper thumbnail of X-CHIP: an integrated platform for high-throughput protein crystallization and on-the-chip X-ray diffraction data collection

Acta Crystallographica Section D Biological Crystallography, 2011

Research paper thumbnail of Crystal structure of alkyl hydroperoxidase D like protein PA0269 from Pseudomonas aeruginosa: Homology of the AhpD-like structural family

BMC Structural Biology, 2011

Background Alkyl hydroperoxidase activity provides an important antioxidant defense for bacterial... more Background Alkyl hydroperoxidase activity provides an important antioxidant defense for bacterial cells. The catalytic mechanism requires two peroxidases, AhpC and AhpD, where AhpD plays the role of an essential adaptor protein. Results The crystal structure of a putative AhpD from Pseudomonas aeruginosa has been determined at 1.9 Å. The protein has an all-helical fold with a chain topology similar to a known AhpD from Mycobacterium tuberculosis despite a low overall sequence identity of 9%. A conserved two α-helical motif responsible for function is present in both. However, in the P. aeruginosa protein, helices H3, H4 of this motif are located at the N-terminal part of the chain, while in M. tuberculosis AhpD, the corresponding helices H8, H9 are situated at the C-terminus. Residues 24-62 of the putative catalytic region of P. aeruginosa have a higher sequence identity of 33% where the functional activity is supplied by a proton relay system of five residues, Glu36, Cys48, Tyr50, ...

Research paper thumbnail of research papers Acta Crystallographica Section D Biological

X-CHIP: an integrated platform for high-throughput protein crystallization and on-the-chip X-ray ... more X-CHIP: an integrated platform for high-throughput protein crystallization and on-the-chip X-ray diffraction data collection

Research paper thumbnail of protein PA0269 from Pseudomonas aeruginosa

Homology of the AhpD-like structural family

Research paper thumbnail of Echo Milestones: A Novel Simulation-Based Echocardiography Competence Tool for Formative Assessment in Cardiology Training

Journal of the American College of Cardiology, 2017

Background: There is a paradigm shift in cardiology education to competency-based approaches, whi... more Background: There is a paradigm shift in cardiology education to competency-based approaches, which promote skill development through self-regulated learning and multiple formative assessments. We propose a simulation-based echocardiography competence assessment tool (ECAT) in a large Canadian cardiology training program. Methods: Pilot study of cardiology trainees at the University of Toronto in 2016 (n=5 PGY4; n=5 PGY5; n=4 PGY³6). Trainees were oriented to the simulator, had 30 minutes to practice, and underwent ECAT testing. We video-recorded performance and acquired simulated echo videos. Four raters assessed performance in real-time or off-line; we assessed inter-rater reliability. We examined relationships between ECAT score and level of training, self-reported echos seen, performed and interpreted, diagnostic scan quality and end of year exam score. Trainees received video footage immediately, and rater feedback within 2 weeks. We interviewed trainees and rater about their ECAT experience. Results: ECAT score was positively associated with level of training (p=0.0056), previous echos seen (p=0.01), performed (p=0.01), and interpreted (p=0.02), and diagnostic quality of scan (p=0.0006). ECAT score correlated with end of year exam score (p=0.01). Intra-class correlation coefficient was 0.56 and Cronbach coefficient alpha was 0.94. Preliminary review of interview transcripts revealed three areas of discussion: 1) the clinical learning environment is variable, and the simulator offers an innovative, standardized setting to practice skills; 2) trainees, particularly novices, report receiving limited feedback, and valued opportunities to be coached; 3) trainees believed the feedback enhanced their learning and motivation, and requested additional opportunities for future learning. Conclusions: The ECAT process, feedback, and technology were highly valued by by millennial learners. The ECAT has high internal consistency, and scores correlate positively with trainees' clinical experience. While there is a need to improve inter-rater reliability, the validity evidence is promising for using ECAT to provide directions for skills development in echo training.

Research paper thumbnail of Identification of novel fragment-based hits forP. bergheiorotidine 5′-monophosphate decarboxylase

Acta Crystallographica Section A Foundations of Crystallography, 2008

For a quarter of a century the isolation of polymorph from III of paracetamol has been a problem ... more For a quarter of a century the isolation of polymorph from III of paracetamol has been a problem due to its instability. In 1997 P. Di Martino et al [1] published the first route to prepare form III of paracetamol but they were not able to observe an x-ray diffractogram from form III. Recently J.B. Burley et al [2] isolated the polymorphic form III, but they could not draw conclusions from the powder diffractogram due to the large non-crystalline fraction. In this paper we present x-ray powder diffraction data from paracetamol form III as well as data from forms II and I. Also data collected at non-ambient temperatures will be discussed. Lattice parameters and a structure for form III will be proposed on the basis of the collected x-ray powder diffraction data.

![Research paper thumbnail of The structure of SAV1646 fromStaphylococcus aureusbelonging to a new `ribosome-associated' subfamily of bacterial proteins](https://a.academia-assets.com/images/blank-paper.jpg)

Acta Crystallographica Section D Biological Crystallography, 2015

The crystal structure of the SAV1646 protein from the pathogenic microorganismStaphylococcus aure... more The crystal structure of the SAV1646 protein from the pathogenic microorganismStaphylococcus aureushas been determined at 1.7 Å resolution. The 106-amino-acid protein forms a two-layer sandwich with α/β topology. The protein molecules associate as dimers in the crystal and in solution, with the monomers related by a pseudo-twofold rotation axis. A sequence-homology search identified the protein as a member of a new subfamily of yet uncharacterized bacterial `ribosome-associated' proteins with at least 13 members to date. A detailed analysis of the crystal protein structure along with the genomic structure of the operon containing thesav1646gene allowed a tentative functional model of this protein to be proposed. The SAV1646 dimer is assumed to form a complex with ribosomal proteins L21 and L27 which could help to complete the assembly of the large subunit of the ribosome.

Research paper thumbnail of X-CHIP: an integrated platform for high-throughput protein crystallization and on-the-chip X-ray diffraction data collection

Acta Crystallographica Section D Biological Crystallography, 2011

Research paper thumbnail of Crystal structure of alkyl hydroperoxidase D like protein PA0269 from Pseudomonas aeruginosa: Homology of the AhpD-like structural family

BMC Structural Biology, 2011

Background Alkyl hydroperoxidase activity provides an important antioxidant defense for bacterial... more Background Alkyl hydroperoxidase activity provides an important antioxidant defense for bacterial cells. The catalytic mechanism requires two peroxidases, AhpC and AhpD, where AhpD plays the role of an essential adaptor protein. Results The crystal structure of a putative AhpD from Pseudomonas aeruginosa has been determined at 1.9 Å. The protein has an all-helical fold with a chain topology similar to a known AhpD from Mycobacterium tuberculosis despite a low overall sequence identity of 9%. A conserved two α-helical motif responsible for function is present in both. However, in the P. aeruginosa protein, helices H3, H4 of this motif are located at the N-terminal part of the chain, while in M. tuberculosis AhpD, the corresponding helices H8, H9 are situated at the C-terminus. Residues 24-62 of the putative catalytic region of P. aeruginosa have a higher sequence identity of 33% where the functional activity is supplied by a proton relay system of five residues, Glu36, Cys48, Tyr50, ...