Interaction of [Rh2(O2CCH3)4(H2O)2] and [Rh2(O2CCH(OH)Ph)2(phen)2(H2O)2](O2C-CH(OH)Ph)2 With Sulfhydryl Compounds and Ceruloplasmin

The interaction of binuclear rhodium(II) complexes [Rh2(OOCCH3)4(H2O)2], [Rh2{OOCCH(OH)Ph}2(phen)2(H2O)2] {OOCCH(OH)Ph}2, [Rh2(OOCCH3)2(bpy)2(H2O)2](OOCCH3)2 and [Rh2Cl2(OOCMe)2(bpy)2](3H2O) with ceruloplasmin, cysteine, glutathione and coenzyme A have been investigated using. UV-Vis and CD spectroscopies. The complexes containing phen or bpy at pH = 7.4 and 4.0 are readily reduced with sulfhydryl compounds, while rhodium(II) acetate is relatively stable in these conditions. Complex [Rh2{OOCCH(OH)Ph}2(phen)2(H2O)2] strongly changes structure of ceruloplasmin leading to the decrease of of α-helix content and loss of oxidase activity

Augmented versus Virtual Reality Laparoscopic Simulation: What Is the Difference?: A Comparison of the ProMIS Augmented Reality Laparoscopic Simulator versus LapSim Virtual Reality Laparoscopic Simulator

BACKGROUND: Virtual reality (VR) is an emerging new modality for laparoscopic skills training; however, most simulators lack realistic haptic feedback. Augmented reality (AR) is a new laparoscopic simulation system offering a combination of physical objects and VR simulation. Laparoscopic instruments are used within an hybrid mannequin on tissue or objects while using video tracking. This study was designed to assess the difference in realism, haptic feedback, and didactic value between AR and VR laparoscopic simulation. METHODS: The ProMIS AR and LapSim VR simulators were used in this study. The participants performed a basic skills task and a suturing task on both simulators, after which they filled out a questionnaire about their demographics and their opinion of both simulators scored on a 5-point Likert scale. The participants were allotted to 3 groups depending on their experience: experts, intermediates and novices. Significant differences were calculated with the paired t-test. RESULTS: There was general consensus in all groups that the ProMIS AR laparoscopic simulator is more realistic than the LapSim VR laparoscopic simulator in both the basic skills task (mean 4.22 resp. 2.18, P <0.000) as well as the suturing task (mean 4.15 resp. 1.85, P <0.000). The ProMIS is regarded as having better haptic feedback (mean 3.92 resp. 1.92, P <0.000) and as being more useful for training surgical residents (mean 4.51 resp. 2.94, P <0.000). CONCLUSIONS: In comparison with the VR simulator, the AR laparoscopic simulator was regarded by all participants as a better simulator for laparoscopic skills training on all tested feature

Do Basic Psychomotor Skills Transfer Between Different Image-based Procedures?

Background - Surgical techniques that draw from multiple types of image-based procedures (IBP) are increasing, such as Natural Orifice Transluminal Endoscopic Surgery, fusing laparoscopy and flexible endoscopy. However, little is known about the relation between psychomotor skills for performing different types of IBP. For example, do basic psychomotor colonoscopy and laparoscopy skills interact? Methods - Following a cross-over study design, 29 naïve endoscopists were trained on the Simbionix GI Mentor and the SimSurgery SEP simulators. Group C (n = 15) commenced with a laparoscopy session, followed by four colonoscopy sessions and a second laparoscopy session. Group L (n = 14) started with a colonoscopy session, followed by four laparoscopy sessions and a second colonoscopy session. Results - No significant differences were found between the performances of group L and group C in their first training sessions on either technique. With additional colonoscopy training, group C outperformed group L in the second laparoscopy training session on the camera navigation task. Conclusions - Overall, training in the basic colonoscopy tasks does not affect performance of basic laparoscopy tasks (and vice versa). However, to limited extent, training of basic psychomotor skills for colonoscopy do appear to contribute to the performance of angled laparoscope navigation tasks. Thus, training and assessment of IBP typespecific skills should focus on each type of tasks independently. Future research should further investigate the influence of psychometric abilities on the performance of IBP and the transfer of skills for physicians who are experienced in one IBP type and would like to become proficient in another type of IBP.Industrial DesignIndustrial Design Engineerin

Algebraically special axisymmetric solutions of the higher-dimensional vacuum Einstein equation

A d-dimensional spacetime is "axisymmetric" if it possesses an SO(d-2) isometry group whose orbits are (d-3)-spheres. In this paper, algebraically special, axisymmetric solutions of the higher dimensional vacuum Einstein equation (with cosmological constant) are investigated. Necessary and sufficient conditions for static axisymmetric solutions to belong to different algebraic classes are presented. Then general (possibly time-dependent) axisymmetric solutions are discussed. All axisymmetric solutions of algebraic types II, D, III and N are obtained.Comment: 28 page

Suturing training in Augmented Reality: gaining proficiency in suturing skills faster

Background: Providing informative feedback and setting goals tends to motivate trainees to practice more extensively. Augmented Reality simulators retain the benefit of realistic haptic feedback and additionally generate objective assessment and informative feedback during the training. This study researched the performance curve of the adapted suturing module on the ProMIS Augmented Reality simulator. Methods: Eighteen novice participants were pretrained on the MIST-VR to become acquainted with laparoscopy. Subsequently, they practiced 16 knots on the suturing module, of which the assessment scores were recorded to evaluate the gain in laparoscopic suturing skills. The scoring of the assessment method was calculated from the “time spent in the correct area” during the knot tying and the quality of the knot. Both the baseline knot and the knot at the top of the performance curve were assessed by two independent objective observers, by means of a standardized evaluation form, to objectify the gain in suturing skills. Results: There was a statistically significant difference between the scores of the second knot (mean 72.59, standard deviation (SD) 16.28) and the top of the performance curve (mean 95.82, SD 3.05; p < 0.001, paired t-test). The scoring of the objective observers also differed significantly (mean 11.83 and 22.11, respectively; SD 3.37 and 3.89, respectively; p < 0.001) (interobserver reliability Cronbach’s alpha = 0.96). The median amount of repetitions to reach the top of the performance curve was eight, which also showed significant differences between both the assessment score (mean 88.14, SD 13.53, p < 0.001) and scoring of the objective observers of the second knot (mean 20.51, SD 4.14; p < 0.001). Conclusions: This adapted suturing module on the ProMIS Augmented Reality laparoscopic simulator is a potent tool for gaining laparoscopic suturing skills.Industrial DesignIndustrial Design Engineerin

Custom Made Candy Plug for Distal False Lumen Occlusion in Aortic Dissection: International Experience

Objective: To evaluate early and midterm outcomes of the Candy Plug (CP) technique for distal false lumen (FL) occlusion in thoracic endovascular aortic repair for aortic dissection (AD) in a more real world cohort of patients from an international multicentre registry. Methods: A multicentre retrospective study was conducted of all consecutive patients from the contributing centres with subacute and chronic AD treated with the CP technique from October 2013 to April 2020 at 18 centres. Results: A custom made CP was used in 155 patients (92 males, mean age 62 ± 11 years). Fourteen (9%) presented with ruptured false lumen aneurysms. Technical success was achieved in all patients (100%). Clinical success was achieved in 138 patients (89%). The median hospital stay was 7 days (1 – 77). The 30 day mortality rate was 3% (n = 5). Stroke occurred in four patients (3%). Spinal cord ischaemia occurred in three patients (2%). The 30 day computed tomography angiogram (CTA) confirmed successful CP placement at the intended level in all patients. Early complete FL occlusion was achieved in 120 patients (77%). Early (30 day) CP related re-intervention was required in four patients (3%). The early (30 day) stent graft related re-intervention rate was 8% (n = 12). Follow up CTA was available in 142 patients (92%), with a median follow up of 23 months (6 – 87). Aneurysmal regression was achieved in 68 of 142 patients (47%); the aneurysm diameter remained stable in 69 of 142 patients (49%) and increased in five of 142 patients (4%). A higher rate of early FL occlusion was detected in the largest volume centre patients (50 [88%] vs. 70 [71%] from other centres; p = .019). No other differences in outcome were identified regarding volume of cases or learning curve. Conclusion: This international CP technique experience confirmed its feasibility and low mortality and morbidity rates. Aortic remodelling and false lumen thrombosis rates were high and support the concept of distal FL occlusion in AD using the CP technique

Imaging of Streptomyces coelicolor A3(2) with Reduced Autofluorescence Reveals a Novel Stage of FtsZ Localization

Imaging of low abundance proteins in time and space by fluorescence microscopy is typically hampered by host-cell autofluorescence. Streptomycetes are an important model system for the study of bacterial development, and undergo multiple synchronous cell division during the sporulation stage. To analyse this phenomenon in detail, fluorescence microscopy, and in particular also the recently published novel live imaging techniques, require optimal signal to noise ratios. Here we describe the development of a novel derivative of Streptomyces coelicolor A3(2) with strongly reduced autofluorescence, allowing the imaging of fluorescently labelled proteins at significantly higher resolution. The enhanced image detail provided novel localization information for the cell division protein FtsZ, demonstrating a new developmental stage where multiple FtsZ foci accumulate at the septal plane. This suggests that multiple foci are sequentially produced, ultimately connecting to form the complete Z ring. The enhanced imaging properties are an important step forward for the confocal and live imaging of less abundant proteins and for the use of lower intensity fluorophores in streptomycetes

Constitutive expression of ftsZ overrides the whi developmental genes to initiate sporulation of Streptomyces coelicolor

The filamentous soil bacteria Streptomyces undergo a highly complex developmental programme. Before streptomycetes commit themselves to sporulation, distinct morphological checkpoints are passed in the aerial hyphae that are subject to multi-level control by the whi sporulation genes. Here we show that whi-independent expression of FtsZ restores sporulation to the early sporulation mutants whiA, whiB, whiG, whiH, whiI and whiJ. Viability, stress resistance and high-resolution electron microscopy underlined that viable spores were formed. However, spores from sporulation-restored whiA and whiG mutants showed defects in DNA segregation/condensation, while spores from the complemented whiB mutant had increased stress sensitivity, perhaps as a result of changes in the spore sheath. In contrast to the whi mutants, normal sporulation of ssgB null mutants—which fail to properly localise FtsZ—could not be restored by enhancing FtsZ protein levels, forming spore-like bodies that lack spore walls. Our data strongly suggest that the whi genes control a decisive event towards sporulation of streptomycetes, namely the correct timing of developmental ftsZ transcription. The biological significance may be to ensure that sporulation-specific cell division will only start once sufficient aerial mycelium biomass has been generated. Our data shed new light on the longstanding question as to how whi genes control sporulation, which has intrigued scientists for four decades