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Pain is one of the most common reasons for consultation in the ER. As far as class II analgesics are concerned, tramadol is most usually used. According to some data from the literature, it would seem that oxycodone and tramadol are equivalent in terms of analgesia. We have tried to prove that oxycodone (Oxynorm® instant) is not less effective than tramadol (Tradonal® odis) in an emergency unit. This is a prospective, monocentric, randomized study carried out amongst ambulatory patients. Those included in the study were given 1 g of paracetamol and a weight-ajusted dose of either tramadol or oxycodone. Every 30 minutes, a simple numerical scale (NS) was established and the clinical parameters were checked. We studied a total of 121 patients divided into 2 groups. There is an average difference of -1.47 between the average ?NS of the oxycodone group and the average ?NS of the tramadol group, with a confidence interval of 95 % (-9.42 - 6.48). The confidence interval does not cross the -10 line considered as the acceptable loss of efficiency, which allows us to conclude that oxycodone is not inferior to tramadol. As far as the adverse effects studied are concerned, there is no significant link between the treatment and the appearance of any side effect.La douleur est l’un des motifs de consultation le plus fréquent en salle d’urgence. Au sein du palier 2, l’utilisation du tramadol est la plus fréquente malgré ses effets secondaires fréquents. Des données de la littérature suggèrent une équivalence en termes d’analgésie entre l’oxycodone et le tramadol. Nous avons tenté de montrer la non-infériorité de l’oxycodone (Oxynorm® instant) en comparaison au tramadol (Tradonal® odis) dans un service d’urgence. Cette étude est prospective monocentrique randomisée menée au sein d’une population de patients désignés comme ambulants. Les patients inclus recevaient 1 g de paracétamol et une dose de tramadol ou d’oxycodone ajustée au poids corporel. Une échelle numérique simple (EN), outil d’évaluation de la douleur, a été réalisée toutes les 30 minutes, accompagnée par la prise des paramètres cliniques. Nous avons étudié un total de 121 patients. La moyenne de la différence entre la moyenne de ?EN du groupe oxycodone et la moyenne de ?EN du groupe tramadol est de -1,47 (IC à 95 % -9,42 – 6,48). L’intervalle de confiance ne vient pas croiser la valeur de -10 fixée comme la perte d’efficacité acceptable, ce qui nous permet de conclure à la non-infériorité de l’oxycodone par rapport au tramadol. Il n’y a pas d’association significative entre le traitement et le fait de présenter des effets secondaires.

This article presents survey results from 2013 to 2016 that show an increase in public awareness of fracking in Pennsylvania. It suggests that the increased awareness of fracking is due to the expansion of the industry in the Commonwealth, lowered gas prices, and increased political discussion following the 2014 gubernatorial race and that it is also part of a national trend. Results of a Pennsylvania survey and three national surveys show opinions split along gender and partisan lines.

Early diagnosis and treatment of intracranial hypertension (ICHT) are major components of the management of neurological emergencies. The optic nerve sheath diameter is closely dependent on intracranial pressure and can be measured by bedside ultrasound (US). We report the story of a 70-year-old COPD patient initially admitted to the emergency room for a sepsis of pulmonary origin. An unusual confusion prompted us to perform an US of the optic nerve sheath. This exam clearly suggested the presence of an ICHT. Hence, the diagnostic approach was proceeded and a herpetic encephalitis was demonstrated and successfully treated. In this clinical report, the optic nerve sheath US guided the diagnostic approach and, eventually, therapeutic decision. Several papers have shown the close relationship between increased optic nerve sheath diameter and intracranial hypertension, but we still need further studies to validate a threshold value of this diameter. The clinical relevance of the US optic nerve diameter measure appears interesting. However, further studies on larger samples of patients are needed to confirm this and to establish a validated threshold value.La précocité du diagnostic et du traitement de l’hypertension intracrânienne (HTIC) est un élément majeur de la prise en charge des pathologies neurologiques aux urgences. Le diamètre de la gaine des nerfs optiques est le reflet direct de la pression intracrânienne et peut être mesuré à l’aide de l’échographie au lit du patient. Nous relatons le cas d’un patient de 70 ans, initialement pris en charge pour un sepsis d’origine pulmonaire dans un contexte de BPCO, et chez qui une confusion inhabituelle a mené à la réalisation d’une échographie de la gaine des nerfs optiques. Celle-ci ayant mis en évidence une HTIC, la démarche diagnostique a été poussée plus en avant et une encéphalite zostérienne a été mise en évidence et traitée précocement avec efficacité. Dans ce cas clinique, l’échographie des nerfs optiques occupe une place prépondérante dans la démarche diagnostique et thérapeutique. L’efficacité de la mesure de la gaine des nerfs optiques pour diagnostiquer une HTIC est démontrée; cependant, il n’existe pas, à l’heure actuelle, de consensus sur une valeur «seuil» de diamètre de la gaine. De nouvelles études sont nécessaires pour préciser ce paramètre.

High levels of fine particulate matter and ozone in many major cities are causing increased respiratory problems, increased asthma attacks and premature death. Natural gas vehicles have been reported to emit up to 95% less particulate matter than diesel powered vehicles and up to 90% less ozone-producing carbon monoxide and reactive hydrocarbons. The adoption of natural gas vehicles, therefore, could play a large role in improving air quality in many cities. Because of the many costs associated with the introduction of a new fueling infrastructure, optimum distribution of fueling stations will play a major role in widespread use of natural gas vehicles, especially in the early stages of market penetration. A model was developed that can be used to optimize fueling station placement-based on traffic volume using a Monte Carlo algorithm. In particular, the Monte Carlo method allows for the placement of the fueling stations based upon their proximity to high volume traffic flow and the placement of all the fueling stations are optimized simultaneously. Traffic volume data from Pittsburgh, PA was used in the model simulations.

One of the many concerns for parents of young children and caregivers of geriatric patients is the potential for scalds. Skin tissue can be thinner and more susceptible to scalds, and the accidental spilling of hot soups can be a common source of burns. The type of soup, however, may not elicit any such misgivings. Here, we elucidate the effects of reduced skin thickness on the severity of soup burns. In particular, we compare the two most popular types of soups (tomato and chicken noodle) along with hot water, to identify the roles that the viscosity and solid constituents in these different soups may play in the severity of the burn. We find that the more solid constituents in the chicken noodle soup, in particular, prevents the soup from flowing from the skin, which increases the time of exposure to elevated temperatures, and therefore increases the severity of the burn.

Recent interest in concentrating photovoltaics (CPV) have led to research and development of multiple CPV systems throughout the world. Much of the focus has been on 3D high concentration systems without cell cooling. This research makes use of a system simulation to model a medium 2D solar concentration energy system with an active cooling system. The simulation encompasses the modeling of a GaInP/GaAs/Ge triple-junction solar cell, the fluid and heat transfer properties of the cooling system, and the storage tank. The simulation was coded in Engineering Equation Solver and was used to simulate the linear concentrating photovoltaic system (LCPV) under Phoenix, AZ, solar and climactic conditions for a full year. The output data from this simulation was used to evaluate the LCPV system from an economic and environmental perspective, showing that over one year a 6.2 kWp LCPV system would save a residential user $1623 in electricity and water heating, as well as displace 10.35 tons of CO 2 .

Surgery for abdominal aortic aneurysm may be challenging when rare renal or venous anomalies are present. This article reports two similar cases of aortic abdominal aneurysm associated with horseshoe kidney and left-sided inferior vena cava treated with a transperitoneal approach. Preoperative knowledge of the anatomic situation enabled appropriate aneurysm repair. Operative strategy is discussed. This report describes an uncommon venous vascular malformation complex and stresses the importance of computed tomography imaging not only in assessing the characteristics of the aneurysmal disease but also in detecting variations in pertinent vascular or parenchymal anatomy.

Recent studies have shown that cholesterol plays a significant role in the ability of Toxin A from Clostridium difficile to enter eukaryotic cells. The translocation process is one of three major steps during intoxication that could be targeted for intervention against the severe antibiotic-associated diarrhea caused by C. difficile.

Aim of the study : To evaluate the role of perioperative, catheter-guided fibrinolysis in the management of thrombosed popliteal artery aneurysms. Material : From 1990 to 2005, six patients suffering subacute limb ischemia, secondary to thrombosis of a popliteal artery aneurysm, benefited selective intra-arterial fibrinolysis, followed by subsequent aneurysm exclusion and bypass grafting. This represents ten percent of all popliteal aneurysms operated on in that time period and 28% of all throm- bosed popliteal artery aneurysms. Results : The lytic procedure was successful in all cases, restituting patency in two (n = 3), one (n = 2) or all (n = 1) crural arteries. The venous bypass graft remained patent in all but one patient. In one patient, the graft occluded at 10 months without limb loss. This outcome compares more favorable than the result obtained with emergent surgery alone for thrombosed popliteal artery aneurysms with profound limb ischemia (eight patients, of whom one required amputation at day 5 and one lost his limb at nine months following graft thrombosis). Conclusion : Preoperative intra-arterial lytic therapy, in the setting of subacute limb ischemia caused by thrombosis of a popliteal artery aneurysm, can be considered as safe and effective.

We investigated the emergence of visually realistic contour in the human figure drawing. Young children initially draw geometric and regular parts, which they combine in an additive fashion. Thus, their human figures look artificial. In one longitudinal study covering ages 6-10 years, and two cross-sectional studies covering ages 5-11 years, we examined when children draw visually realistic looking shapes, which are integrated into a figure silhouette. Both aspects, drawing of parts with a visually realistic contour and integration into a whole, gradually increased but took several years to unfold. In the most prescriptive task of Study 3, analyses of growth curves indicated that mastery of drawing contour may require either of two kinds of cognitive investment: first, gradually increasing attention to perceptual detail, and/or second, more conceptual processing when attending to the spatial layout of the whole figure silhouette.

Uridine-5′-diphospho-1-α-d-glucose (UDP-Glc) is a common substrate used by glucosyltransferases, including certain bacterial toxins such as Toxins A and B from Clostridium difficile. Fluorescent analogs of UDP-Glc have been prepared for use in our studies of the clostridial toxins. These compounds are related to the methylanthraniloyl-ATP compounds commonly used to probe the chemistry of ATP-dependent enzymes. The reaction of excess methylisatoic anhydride with UDP-Glc in aqueous solution yields primarily the 2′ and 3′ isomers of methylanthraniloyl-UDP-Glc (MUG). As the 2′ and 3′ isomers readily interconvert, this isomeric mixture was copurified by HPLC away from the other isomeric products, and was characterized by a combination of NMR, fluorescence and mass spectrometric methods. TcdA binds MUG competitively with respect to UDP-Glc with an affinity of 15 ± 2 µm in the absence of Mg2+. There is currently no evidence that the fluorescent substrate analog is turned over by the toxin in either glucosyltransferase or glucosylhydrolase reactions. Using a competition assay, the affinity of UDP-Glc was determined to be 45±10 µm in the absence of Mg2+. The binding of UDP-Glc and Mg2+ are highly coupled with Mg2+ affinities in the range of 90–600 µm, depending on the experimental conditions. These results imply that one of the significant roles of the metal ion might be to stabilize the enzyme–substrate complex prior to initiation of the transferase chemistry.

Introduction Groin lymphatic fistulas are a troublesome finding after limb revascularization surgery. Its management represents a difficult task for the clinician. Report We report our experience in the treatment of such a condition with negative-pressure wound therapy (NPWT) in a 70-year-old man which benefited from extra-anatomic prosthetic axillofemoral bypass. After a week of treatment, the fistula dried up and closure was obtained with simple suture under local anaesthesia. Follow-up at 9 months showed stable coverage without any sign of leakage. Discussion This study depicts NPWT as an effective non-invasive treatment in the management of groin lymphocutaneous fistula.

The recent focus on renewable energy has lead to an increased awareness of solar energy. Concentrating photovoltaic systems have seen a resurgence in research interest since their earlier pilot plant origins in the 1970s and 1980s. The use of concentration reduces the amount of expensive photovoltaic materials while maintaining a high level of incident solar radiation. This research combines the advantage of concentrating solar energy with high efficiency multijunction cells and an active cooling system to create a system that efficiently produces both electricity and heat. A linear concentrating photovoltaic system model was developed in order to simulate the system under actual solar and climatic conditions, where a number of different system variables can be adjusted. This simulation was used to evaluate the effects of domestic hot water use on a 6.2 kWp system. The results show the changes in solar cell efficiency, electricity produced, thermal energy produced, dollar value displaced, and global warming potential displaced as the domestic hot water use of the system is varied. This simulation can be used to find an optimal system for given input conditions and can be used to find optimal operating conditions for a given system size.

Protein-ligand docking is an essential technique in computer-aided drug design. While generally available docking programs work well for most drug classes, carbohydrates and carbohydrate-like compounds are often problematic for docking. We present a new docking method specifically designed to handle docking of carbohydrate-like compounds. BALLDock/SLICK combines an evolutionary docking algorithm for flexible ligands and flexible receptor side chains with carbohydrate-specific scoring and energy functions. The scoring function has been designed to identify accurate ligand poses, while the energy function yields accurate estimates of the binding free energies of these poses. On a test set of known protein-sugar complexes we demonstrate the ability of the approach to generate correct poses for almost all of the structures and achieve very low mean errors for the predicted binding free energies.

Protein-ligand docking is an essential technique in computer-aided drug design. While generally available docking programs work well for most drug classes, carbohydrates and carbohydrate-like compounds are often problematic for docking. We present a new docking method specifically designed to handle docking of carbohydrate-like compounds. BALLDock/SLICK combines an evolutionary docking algorithm for flexible ligands and flexible receptor side chains with carbohydrate-specific scoring and energy functions. The scoring function has been designed to identify accurate ligand poses, while the energy function yields accurate estimates of the binding free energies of these poses. On a test set of known protein-sugar complexes we demonstrate the ability of the approach to generate correct poses for almost all of the structures and achieve very low mean errors for the predicted binding free energies.

Recently a new computed tomography semiology of the pulmonary adenocarcinoma was highlighted. Studies on ground-glass nodule and on mixed nodule showed the relation between these radiological images and the different anatomopathological forms of lung adenocarcinoma. Ground-glass opacity can correspond to precancerous lesions and morphological characteristics of nodules are correlated with the prognosis. The presence of spiculation, pleural retraction and air bronchogram is significantly more important in neoplasic lesions. The presence or the apparition of a solid component inside the nodule or the presence of indentation is highly suggestive of adenocarcinoma. A lesion smaller than 20 mm and persistant after 1 month must be, either followed up, or removed by a limited surgical resection. Lesions larger than 20 mm or associated with a solid component must be treated by conventional surgery.

Standard 12-lead electrocardiogram (ECG) is, with biomarkers, the most accurate method in the diagnosis of acute coronary syndrome (ACS). However, posterior (V7-V8-V9) and right (V3R-V4R-V5R) derivations are not systematically performed due to the time-consuming procedure involved, despite major therapeutic implications (fluid loading instead of nitrates use in right ventricular involvement) and published guidelines [1]. Recently, an 18-lead ECG system, standard 12-lead ECG and six additional synthesized leads (assessing posterior and right ventricular areas) in only one recording procedure has been developed. The reliability of this material (ECG 2550; Nihon Kohden Co. Ltd, Japan) was already validated in this indication in an Asian population [2,3].

Protein-carbohydrate interactions are increasingly being recognized as essential for many important biomolecular recognition processes. From these, numerous biomedical applications arise in areas as diverse as drug design, immunology, or drug transport. We introduce SLICK, a package containing a scoring and an energy function, which were specifically designed to predict binding modes and free energies of sugars and sugarlike compounds to proteins. SLICK accounts for van der Waals interactions, solvation effects, electrostatics, hydrogen bonds, and CH...pi interactions, the latter being a particular feature of most protein-carbohydrate interactions. Parameters for the empirical energy function were calibrated on a set of high-resolution crystal structures of protein-sugar complexes with known experimental binding free energies. We show that SLICK predicts the binding free energies of predicted complexes (through molecular docking) with high accuracy. SLICK is available as part of our molecular modeling package BALL (www.ball-project.org).

Objective: To assess factors influencing operative and long-term outcome in octogenarians undergoing aortic valve surgery (AVR). Methods: Records of 220 consecutive octogenarians having AVR between 1992 and 2004 were reviewed, and follow-up obtained (99% complete). Of the group (mean age: 82.8 years; 174 females), 142 patients (65%) were in New York Heart Association (NYHA) class III—IV, 22 (10%) had previous myocardial infarction, 11 (5%) had previous coronary artery bypass grafting (CABG), and 8 (4%) had percutaneous aortic valvuloplasty. There were 44 urgent procedures (20%), and additional CABG was performed in 58 patients (26%). Results: Operative mortality was 13% (9% for AVR, 24% for AVR + CABG). Among the 29 patients who died, 14 (48%) were operated on urgently (32% mortality for urgent procedures). Causes of hospital death were respiratory insufficiency or infection in 16 patients (16/29 = 55%), myocardial infarction in 8 (28%), stroke in 2 (7%), sepsis in 2 (7%), and renal failure in 1 (3%). Significant postoperative complications were atrial fibrillation in 48 patients (22%), respiratory insufficiency in 46 (21%), permanentatrio-ventricular bloc in 12 (5%), myocardial infarctionin10 (5%), hemodialysis in 4 (2%), and stroke in 4 (2%). Meanhospital and intensive care unit (ICU) stays were 17.6 5.2 and 6.9 3.4 days, respectively. Multivariate predictors (p < 0.05) of hospital death were urgent procedure, associated CABG, NYHA class IV, and percutaneous aortic valvuloplasty. Age, associated CABG, and urgent procedure were predictors of prolonged ICU stay. Mean follow-up was 58.2 months and actuarial 5-year survival was 73.2 6.9%. Age, preoperative myocardial infarction, urgent procedure, and duration of ICU stay were independent predictors of late death. Among 130 patients alive at follow-up, 91% were angina free and 81% in class I—II. Conclusions: AVR in octogenarians can be performed with acceptable mortality, although significant morbidity. These results stress the importance of early operation on elderly patients with aortic valve disease, avoiding urgent procedures. Associated coronary artery disease is a harbinger of poor operative outcome. Long-term survival and functional recovery are excellent. # 2007 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Infected abdominal aortic aneurysms are uncommon but not rare (1-3% of all abdominal aortic aneurysms). This life-threatening disease can lead to rapid uncontrolled sepsis and/or aortic rupture. We report one case that underlines two notions. Firstly computed tomography is effective to detect early stages of the pathology providing complete depiction of the anatomical abnormalities. Secondly infected aortic aneurysm can be successfully treated by antibiotherapy and in situ replacement with cryopreserved arterial homograft.

In drug design, the prediction of the binding mode of drug-like substances in the binding site of a receptor is one of the most important tools. Over the last years, many different approaches have been developed and applied successfully to a number of substances. However, some classes of substances are still hard to predict with docking techniques. One very important class of such molecular complexes is the domain of carbohydrates binding to proteins. This thesis introduces an approach to protein-carbohydrate docking. The method is based on thorough analysis of those interactions, which are important for protein-carbohydrate complexes. Computational models of these effects are employed for creating a scoring and an energy function for this kind of complexes. By integrating these functions into a docking programme, the effectiveness of this new approach is proven. After a brief introduction into the problem addressed by this theses, the biochemical background of protein-carbohydrate complexation is explained. The main characteristics of such complexes, which are the basis for the development of the functions, are detailed. Furthermore, physical models for the atomic interactions that are deemed important for protein-carbohydrate complexes are explained. Based on these interactions, the SLICK package, consisting of an energy function and a scoring function is developed. The effectiveness of both functions is proven. Eventually, their effectiveness in protein-carbohydrate docking is shown by integrating SLICK into a molecular docking programme. In der Wirkstoffentwicklung ist das so genannte Docking, also die Vorhersage des Bindungsmodus wirkstoffähnlicher Moleküle an einen Rezeptor, ein wichtiges Werkzeug. In den letzten Jahren wurde eine Vielzahl von Methoden und Ansätzen entwickelt und für eine Reihe von Wirkstoffklassen erfolgreich eingesetzt. Jedoch gibt es immer noch Bereiche, in denen Dockingverfahren scheitern. Eine wichtige Klasse von Molekülkomplexen, die mit Dockingverfahren immer noch schwer zu handhaben sind, stellen zuckerbindende Proteine dar. Die vorliegende Arbeit stellt einen Ansatz vor, der das Docking von Zuckern an Proteine ermöglicht. Dieses Verfahren basiert auf einer genauen Analyse der für Protein-Zucker-Komplexe wichtigen Wechselwirkungen und der Modellierung jener Eigenschaften in Form einer Energie- und einer Scoringfunktion. Es wird gezeigt, dass durch die Einbettung dieser beiden Funktionen in ein Dockingprogramm eine automatische Vorhersage des Bindungsmodus von Protein-Zucker-Komplexen möglich wird. Nach einer knappen Einführung in das zu behandelnde Problem beleuchtet diese Arbeit den biochemischen Hintergrund der Bindung von Zuckern an Proteine. Dabei werden die Hauptmerkmale erläutert, die für die Entwicklung eines Dockingverfahrens von Bedeutung sind. Desweiteren werden physikalische Modelle für die für Protein-Zucker-Komplexe charakteristischen atomaren Wechselwirkungen behandelt. Aufbauend auf diesen Modellen werden Scoring- und Energiefunktion entwickelt, die zusammen das Paket SLICK bilden. Es wird gezeigt, dass die Scoringfunktion in der Lage ist, aus einer großen Menge von Dockingkandidaten viel versprechende Strukturen herauszufiltern. Anschließend wird die Vorhersagequalität der Energiefunktion statistisch anhand verfügbarer experimenteller Daten analysiert. Schließlich wird durch die Integration von SLICK in ein Dockingprogramm nachgewiesen, dass mit Hilfe der in dieser Arbeit entwickelten Verfahren das bisher schwierige Problem des Dockings von Zuckern an Proteine lösbar wird.

To assess risk factors for early and late outcome after concurrent carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG).Records of all 311 consecutive patients having concurrent CEA and CABG from 1989 to 2002 were reviewed, and follow-up obtained (100% complete). In the group (mean age 67 years; 74% males), 62% had triple-vessel disease, 57% unstable angina, 31% left main coronary stenosis, 19% congestive heart failure, and 35% either a history of vascular procedures or existing vasculopathies. Preoperative assessment revealed transient ischaemic attack in 16%, stroke in 7%, and bilateral carotid disease in 20%. There were 7% emergent and 19% urgent operations, and ascending aorta was described as atheromatous or calcified in 21%. Hospital death occurred in 19 patients, myocardial infarction in seven, and permanent stroke in 12. Significant multivariable predictors of hospital death were aortic calcifications, coexisting vasculopathy, and emergent procedure. Significant predictors of postoperative stroke were calcified or dilated aorta, and of prolonged hospital stay were advanced age, unstable angina, and coexisting vascular disease. For hospital survivors, 10-year actuarial late event-free rates were: death, 50%; myocardial infarction, 84%; stroke, 93%; percutaneous angioplasty, 95%; redo CABG, 98%; and all morbidity and mortality, 48%. Significant multivariable predictors of late deaths were coexisting vasculopathy, age, renal insufficiency, previous cardiac surgery, tobacco abuse, calcified or atheromatous aorta, and duration of intensive care unit stay.Concurrent CEA and CABG can be performed with acceptable operative mortality and morbidity, and good long-term freedom from coronary and neurologic events. Atheromatous aortic disease is a harbinger of poor operative and long-term outcome.

The paper discusses SiLVIA simulation library. The main purpose of SiLVIA is to supply procedures for simulating the dynamics of colliding rigid bodies and the interactive manipulation of these bodies in virtual environments. Detecting collisions between virtual objects and calculating their reaction to these collisions play an important role in VR applications such as ergonomy, studies or virtual assembly simulations.

Uridine-5'-diphospho-1-alpha-d-glucose (UDP-Glc) is a common substrate used by glucosyltransferases, including certain bacterial toxins such as Toxins A and B from Clostridium difficile. Fluorescent analogs of UDP-Glc have been prepared for use in our studies of the clostridial toxins. These compounds are related to the methylanthraniloyl-ATP compounds commonly used to probe the chemistry of ATP-dependent enzymes. The reaction of excess methylisatoic anhydride with UDP-Glc in aqueous solution yields primarily the 2' and 3' isomers of methylanthraniloyl-UDP-Glc (MUG). As the 2' and 3' isomers readily interconvert, this isomeric mixture was copurified by HPLC away from the other isomeric products, and was characterized by a combination of NMR, fluorescence and mass spectrometric methods. TcdA binds MUG competitively with respect to UDP-Glc with an affinity of 15 +/- 2 microm in the absence of Mg2+. There is currently no evidence that the fluorescent substrate analog is turned over by the toxin in either glucosyltransferase or glucosylhydrolase reactions. Using a competition assay, the affinity of UDP-Glc was determined to be 45+/-10 microm in the absence of Mg2+. The binding of UDP-Glc and Mg2+ are highly coupled with Mg2+ affinities in the range of 90-600 microm, depending on the experimental conditions. These results imply that one of the significant roles of the metal ion might be to stabilize the enzyme-substrate complex prior to initiation of the transferase chemistry.

Aims Because the elderly are increasingly referred for operation, we reviewed the results of cardiac surgery in patients of 80 years or older. Methods and Results Records of 182 consecutive octogenarians who had had cardiac operations between 1992 and 1998 were reviewed. Follow-up was 100% complete. Seventy patients had coronary grafting (CABG), 70 aortic valve replacement, 30 aortic valve replacement+CABG, and 12 mitral valve repair/replacement. Rates of hospital death, stroke, and prolonged stay (>14 days) were as follows: CABG: 7 (10%), 2 (2·8%) and 41 (58%); aortic valve replacement: 6 (8·5%), 2 (2·8%) and 32 (45·7%); aortic valve replacement+CABG: 8 (26·5%), 1 (3·8%) and 14 (46·6%); mitral valve repair/replacement: 3 (25%), 1 (8·3%) and 5 (41·6%). Multivariate predictors ( P