52 research outputs found

    Current training on the basics of robotic surgery in the Netherlands: Time for a multidisciplinary approach?

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    Introduction: The following research questions were answered: (1) What are the training pathways followed by the current robot professionals? (2) Are there any differences between the surgical specialties in robot training and robot use? (3) What is their opinion about multidisciplinary basic skills training? Methods: An online questionnaire was sent to 91 robot professionals in The Netherlands. The questionnaire contained 21 multiple-choice questions focusing on demographics, received robot training, and their opinion on basic skills training in robotic surgery. Results: The response rate was 62 % (n = 56): 13 general surgeons, 16 gynecologists, and 27 urologists. The urologists performed significantly more robotic procedures than surgeons and gynecologists. The kind of training of all professionals varied from a training program by Intuitive Surgical, master-apprenticeship with or without duo console, fellowship, and self-designed training programs. The training did neither differ significantly among the different specialties nor the year of starting robotic surgery. Majority of respondents favor an obliged training program including an examination for the basics of robot skills training. Conclusion: Training of the current robot professionals is mostly dependent on local circumstances and the manufacturer of the robot system. Training is independent of the year of start with robotic surgery and speciality. To guarantee the quality of future training of residents and fellows in robot-assisted surgery, clear training goals should be formulated and implemented. Since this study shows that current training of different specialities does not differ, training in robotic surgery could be started by a multidisciplinary basic skills training and assessment

    Mechanistic Investigations into the Catalytic Levulinic Acid Hydrogenation, Insight in H/D Exchange Pathways, and a Synthetic Route to d<sub>8</sub>-?-Valerolactone

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    gamma-Valerolactone (GVL) is readily accessible by catalytic hydrogenation of carbohydrate-derived levulinic acid (LA) and is an attractive biobased chemical with a wide range of applications in both the chemical (e.g., as biomass-derived solvent) and the transportation fuel sector. In this study, we used isotopic labeling experiments to provide insights into the catalytic hydrogenation pathways involved in the conversion of LA to GVL under different reaction conditions using water as an environmentally benign solvent and Ru/C as a readily available catalyst. H-2 NMR experiments combined with quantum chemical calculations revealed that deuterium atoms can be incorporated at different positions as well as the involvement of the different intermediates 4-hydroxypentanoic acid and alpha-angelica lactone (alpha-AL). The insight provided by these studies revealed an as of yet unexploited sequential deuteration route to synthesize fully deuterated LA and GVL. The route starts by the conversion of LA to alpha-AL followed by a selective deuteration of the acidic protons of alpha-AL by H/D exchange with D2O. Subsequent ring-opening in D2O (d(2)-AL to d(3)-LA) and exchange of the remaining protons of d(3)-LA via a keto-enol tautomerization by heating in D2O under acidic conditions gives d(8)-LA. Finally, the d(8)-LA is catalytically reduced at low temperature using Ru/C with D-2 in D2O to d(8)-GVL

    Loss of HR6B ubiquitin-conjugating activity results in damaged synaptonemal complex structure and increased crossing-over frequency during the male meiotic prophase.

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    The ubiquitin-conjugating enzymes HR6A and HR6B are the two mammalian homologs of Saccharomyces cerevisiae RAD6. In yeast, RAD6 plays an important role in postreplication DNA repair and in sporulation. HR6B knockout mice are viable, but spermatogenesis is markedly affected during postmeiotic steps, leading to male infertility. In the present study, increased apoptosis of HR6B knockout primary spermatocytes was detected during the first wave of spermatogenesis, indicating that HR6B performs a primary role during the meiotic prophase. Detailed analysis of HR6B knockout pachytene nuclei showed major changes in the synaptonemal complexes. These complexes were found to be longer. In addition, we often found depletion of synaptonemal complex proteins from near telomeric regions in the HR6B knockout pachytene nuclei. Finally, we detected an increased number of foci containing the mismatc

    The ubiquitin-conjugating DNA repair enzyme is a maternal factor essential for early embryonic development in mice

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    The Saccharomyces cerevisiae RAD6 protein is required for a surprising diversity of cellular processes, including sporulation and replicational damage bypass of DNA lesions. In mammals, two RAD6-related genes, HR6A and HR6B, encode highly homologous proteins. Here, we describe the phenotype of cells and mice deficient for the mHR6A gene. Just like mHR6B knockout mouse embryonic fibroblasts, mHR6A-deficient cells appear to have normal DNA damage resistance properties, but mHR6A knockout male and female mice display a small decrease in body weight. The necessity for at least one functional mHR6A (X-chromosomal) or mHR6B (autosomal) allele in all somatic cell types is supported by the fact that neither animals lacking both proteins nor females with only one intact mHR6A allele are viable. In striking contrast to mHR6B knockout males, which show a severe spermatogenic defect, mHR6A knockout males are normally fertile. However, mHR6A knockout females fail to produce offspring despite a normal ovarian histology and ovulation. The absence of mHR6A in oocytes prevents development beyond the embryonic two-cell stage but does not result in an aberrant methylation pattern of histone H

    No evidence for an association of plasma homocysteine levels and refractive error - Results from the population-based Gutenberg Health Study (GHS)

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    Purpose There is a strong association between severe hyperhomocysteinemia and myopia. Thus we studied the hypothesis that even moderately increased levels of homocysteine (Hcy) might be a potentially treatable risk factor for myopia. Methods The Gutenberg Health Study (GHS) is a population-based, prospective, observational cohort study in Germany, including 15,010 participants aged between 35 and 74 at recruitment. The baseline examination was conducted from 2007-2012. Refraction was measured using autorefraction (HARK 599, Carl Zeiss AG, Jena, Germany). Hcy was measured by an immunoassay. We included only phakic participants without a history of corneal surgery or corneal laser treatment. We used linear regression models to evaluate the potential association between Hcy and refraction at baseline, and between Hcy and change in refraction between baseline and 5-year-follow-up examination. We used generalized estimating equation models to account for the correlation between fellow eyes. Results We included 13,749 participants, categorized as having no myopia (spherical equivalent > -0.75 D, 65.2%), low myopia (-0.75 D-2.75 D, 21.5%), moderate myopia (-3.00 D- 5.75 D, 9.8%) and high myopia (≤ -6
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