520 research outputs found
Current reflections of the vascular surgeon on the assessment and treatment of critical limb ischaemia
How to evaluate the quality of fracture reduction and fixation of the wrist and ankle in clinical practice: a Delphi consensus
METHOD: A Delphi study was conducted to obtain consensus on the most important criteria for the radiological evaluation of the reduction and fixation of the wrist and ankle. The Delphi study consisted of a bipartite online questionnaire, focusing on the interpretation of radiographs and CT scans of the wrist and the ankle. Questions addressed imaging techniques, aspects of the anatomy and fracture reduction and fixation. Agreement was expressed as the percentage of respondents with similar answers. Consensus was defined as an agreement of at least 90%. RESULTS: In three Delphi rounds, respectively, 64, 74 and 62 specialists, consisting of radiologists, trauma and orthopaedic surgeons from the Netherlands responded. After three Delphi rounds, consensus was reached for three out of 14 (21%) imaging techniques proposed, 11 out of the 13 (85%) anatomical aspects and 13 of the 22 (59%) items for the fracture reduction and fixation. This Delphi consensus differs from existing scoring protocols in terms of the greater number of anatomical aspects and aspects of fracture fixation requiring evaluation and is more suitable in clinical practice due to a lower emphasis on measurements
History and structure of the closed pedigreed population of Icelandic Sheepdogs
<p>Abstract</p> <p>Background</p> <p>Dog breeds lose genetic diversity because of high selection pressure. Breeding policies aim to minimize kinship and therefore maintain genetic diversity. However, policies like mean kinship and optimal contributions, might be impractical. Cluster analysis of kinship can elucidate the population structure, since this method divides the population in clusters of related individuals. Kinship-based analyses have been carried out on the entire Icelandic Sheepdog population, a sheep-herding breed.</p> <p>Results</p> <p>Analyses showed that despite increasing population size and deliberately transferring dogs, considerable genetic diversity has been lost. When cluster analysis was based on kinships calculated seven generation backwards, as performed in previous studies, results differ markedly from those based on calculations going back to the founder-population, and thus invalidate recommendations based on previous research. When calculated back to the founder-population, kinship-based clustering reveals the distribution of genetic diversity, similarly to strategies using mean kinship.</p> <p>Conclusion</p> <p>Although the base population consisted of 36 Icelandic Sheepdog founders, the current diversity is equivalent to that of only 2.2 equally contributing founders with no loss of founder alleles in descendants. The maximum attainable diversity is 4.7, unlikely achievable in a non-supervised breeding population like the Icelandic Sheepdog. Cluster analysis of kinship coefficients can provide a supporting tool to assess the distribution of available genetic diversity for captive population management.</p
Comment on: Lipsky and Berendt. Hyperbaric Oxygen Therapy for Diabetic Foot Wounds: Has Hope Hurdled Hype? Diabetes Care 2010;33:1143–1145
Delphi study to reach international consensus among vascular surgeons on major arterial vascular surgical complications
BackgroundThe complications discussed with patients by surgeons prior to surgery vary, because no consensus on major complications exists. Such consensus may improve informed consent and shared decision-making. This study aimed to achieve consensus among vascular surgeons on which complications are considered major' and which minor,' following surgery for abdominal aortic aneurysm (AAA), carotid artery disease (CAD) and peripheral artery disease (PAD).MethodsComplications following vascular surgery were extracted from Cochrane reviews, national guidelines, and reporting standards. Vascular surgeons from Europe and North America rated complications as major or minor on five-point Likert scales via an electronic Delphi method. Consensus was reached if >= 80% of participants scored 1 or 2 (minor) or 4 or 5 (major).ResultsParticipants reached consensus on 9-12 major and 6-10 minor complications per disease. Myocardial infarction, stroke, renal failure and allergic reactions were considered to be major complications of all three diseases. All other major complications were treatment specific or dependent on disease severity, e.g., spinal cord ischemia, rupture following AAA repair, stroke for CAD or deep wound infection for PAD.ConclusionVascular surgeons reached international consensus on major and minor complications following AAA, CAD and PAD treatment. This consensus may be helpful in harmonizing the information patients receive and improving standardization of the informed consent procedure. Since major complications differed between diseases, consensus on disease-specific complications to be discussed with patients is necessary
A monitor for Cellular Oxygen METabolism (COMET): monitoring tissue oxygenation at the mitochondrial level
After introduction of the protoporphyrin IX-triplet state lifetime technique as a new method to measure mitochondrial oxygen tension in vivo, the development of a clinical monitor was started. This monitor is the “COMET”, an acronym for Cellular Oxygen METabolism. The COMET is a non-invasive electrically powered optical device that allows measurements on the skin. The COMET is easy to transport, due to its lightweight and compact size. After 5-aminolevulinic acid application on the human skin, a biocompatible sensor enables detection of PpIX in the mitochondria. PpIX acts as a mitochondrially located oxygen-sensitive dye. Three measurement types are available in the touchscreen-integrated user interface, ‘Single’, ‘Interval’ and ‘Dynamic measurement’. COMET is currently used in several clinical studies in our institution. In this first description of the COMET device we show an incidental finding during neurosurgery. To treat persisting intraoperative hypertension a patient was administered clonidine, but due to rapid administration an initial phase of peripheral vasoconstriction occurred. Microvascular flow and velocity parameters measured with laser-doppler (O2C, LEA Medizintechnik) decreased by 44 and 16% respectively, but not the venous-capillary oxygen saturation. However, mitochondrial oxygen tension in the skin detected by COMET decreased from a steady state of 48 to 16 mmHg along with the decrease in flow and velocity. We conclude that COMET is ready for clinical application and we see the future for this bedside monitor on the intensive care, operating theater, and testing of mitochondrial effect of pharmaceuticals
Delphi Study to Reach International Consensus Among Vascular Surgeons on Major Arterial Vascular Surgical Complications
Background: The complications discussed with patients by surgeons prior to surgery vary, because no consensus on major complications exists. Such consensus may improve informed consent and shared decision-making. This study aimed to achieve consensus among vascular surgeons on which complications are considered ‘major’ and which ‘minor,’ following surgery for abdominal aortic aneurysm (AAA), carotid artery disease (CAD) and peripheral artery disease (PAD). Methods: Complications following vascular surgery were extracted from Cochrane reviews, national guidelines, and reporting standards. Vascular surgeons from Europe and North America rated complications as major or minor on five-point Likert scales via an electronic Delphi method. Consensus was reached if ≥ 80% of participants scored 1 or 2 (minor) or 4 or 5 (major). Results: Participants reached consensus on 9–12 major and 6–10 minor complications per disease. Myocardial infarction, stroke, renal failure and allergic reactions were considered to be major complications of all three diseases. All other major complications were treatment specific or dependent on disease severity, e.g., spinal cord ischemia, rupture following AAA repair, stroke for CAD or deep wound infection for PAD. Conclusion: Vascular surgeons reached international consensus on major and minor complications following AAA, CAD and PAD treatment. This consensus may be helpful in harmonizing the information patients receive and improving standardization of the informed consent procedure. Since major complications differed between diseases, consensus on disease-specific complications to be discussed with patients is necessary
Direct visualization reveals dynamics of a transient intermediate during protein assembly
Interactions between proteins underlie numerous biological functions. Theoretical work suggests that protein interactions initiate with formation of transient intermediates that subsequently relax to specific, stable complexes. However, the nature and roles of these transient intermediates have remained elusive. Here, we characterized the global structure, dynamics, and stability of a transient, on-pathway intermediate during complex assembly between the Signal Recognition Particle (SRP) and its receptor. We show that this intermediate has overlapping but distinct interaction interfaces from that of the final complex, and it is stabilized by long-range electrostatic interactions. A wide distribution of conformations is explored by the intermediate; this distribution becomes more restricted in the final complex and is further regulated by the cargo of SRP. These results suggest a funnel-shaped energy landscape for protein interactions, and they provide a framework for understanding the role of transient intermediates in protein assembly and biological regulation
The resting oxidized state of small laccase analyzed with paramagnetic NMR spectroscopy
nuclei. Two sequence-specific assignments are proposed on the basis of a second-coordination shell variant that also lacks the copper ion at the T1 site, SLAC-T1D/Q291E. This double mutant is found to be exclusively in the RO state, revealing a subtle balance between the RO and the NI states.NWONWO-BOO 022.005.029Macromolecular BiochemistrySolid state NMR/Biophysical Organic Chemistr
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