Xenogeneic, extracorporeal liver perfusion in primates improves the ratio of branched-chain amino acids to aromatic amino acids (Fischer's ratio)

In fulminant hepatic failure (FHF), the development of hepatic encephalopathy is associated with grossly abnormal concentrations of plasma amino acids (PAA). Normalization of the ratio of branched-chain amino acids to aromatic amino acids (Fischer's ratio) correlates with clinical improvement. This study evaluated changes in PAA metabolism during 4 h of isolated, normothermic extracorporeal liver perfusion using a newly designed system containing human blood and a rhesus monkey liver. Bile and urea production were within the physiological range. Release of the transaminases AST, ALT and LDH were minimal. The ratio of branched (valine, leucine, isoleucine) to aromatic (tyrosine, phenylalanine) amino acids increased significantly. These results indicate that a xenogeneic extracorporeal liver perfusion system is capable of significantly increasing Fischer's ratio and may play a role in treating and bridging patients in FHF in the future

Alfvén waves in the near-PSBL lobe: Cluster observations

Electromagnetic low-frequency waves in the magnetotail lobe close to the PSBL (Plasma Sheet Boundary Layer) are studied using the Cluster spacecraft. The lobe waves show Alfvénic properties and transport their wave energy (Poynting flux) on average toward the Earth along magnetic field lines. Most of the wave events are rich with oxygen (O+) ion plasma. The rich O+ plasma can serve to enhance the magnetic field fluctuations, resulting in a greater likelihood of observation, but it does not appear to be necessary for the generation of the waves. Taking into account the fact that all events are associated with auroral electrojet enhancements, the source of the lobe waves might be a substorm-associated instability, i.e. some instability near the reconnection site, or an ion beam-related instability in the PSBL

Causal trajectories description of atom diffraction by surfaces

9 pages, 7 figures -- PACS numbers: 79.20.Rf, 03.65.Sq, 03.65.BzThe method of quantum trajectories proposed by de Broglie and Bohm is applied to the study of atom diffraction by surfaces. As an example, a realistic model for the scattering of He off corrugated Cu is considered. In this way, the final angular distribution of trajectories is obtained by box-counting, which is in excellent agreement with the results calculated by standard S-matrix methods of scattering theory. More interestingly, the accumulation of quantum trajectories at the different diffraction peaks is explained in terms of the corresponding quantum potential. This non-local potential "guides" the trajectories causing a transition from a distribution near the surface, which reproduces its shape, to the final diffraction pattern observed in the asymptotic region, far from the diffracting object. These two regimes are homologous to the Fresnel and Fraunhofer regions described in undulatory optics. Finally, the turning points of the quantum trajectories provide a better description of the surface electronic density than the corresponding classical ones, usually employed for this task.This work was supported by DGES (Spain) under contracts No PB95-71, PB95-425 and PB96-76. A.S. Sanz also acknowledges the Universidad Autónoma de Madrid for a doctoral grant.Peer reviewe

Plasma convection in the magnetotail lobes: statistical results from Cluster EDI measurements

A major part of the plasma in the Earth's magnetotail is populated through transport of plasma from the solar wind via the magnetotail lobes. In this paper, we present a statistical study of plasma convection in the lobes for different directions of the interplanetary magnetic field and for different geomagnetic disturbance levels. The data set used in this study consists of roughly 340 000 one-minute vector measurements of the plasma convection from the Cluster Electron Drift Instrument (EDI) obtained during the period February 2001 to June 2007. The results show that both convection magnitude and direction are largely controlled by the interplanetary magnetic field (IMF). For a southward IMF, there is a strong convection towards the central plasma sheet with convection velocities around 10 km s<sup>−1</sup>. During periods of northward IMF, the lobe convection is almost stagnant. A <I>B<sub>y</sub></I> dominated IMF causes a rotation of the convection patterns in the tail with an oppositely directed dawn-dusk component of the convection for the northern and southern lobe. Our results also show that there is an overall persistent duskward component, which is most likely a result of conductivity gradients in the footpoints of the magnetic field lines in the ionosphere

Der Einfluss von Haftungsunsicherheit auf den Sorgfaltsstandard

Optimal abgestimmte Vergütungs- und Haftungsregeln regen den Arzt zu einer effizienten Ressourcenverwendung und einem angemessenen Sorgfaltsniveau an. Die nicht nur in Deutschland zu beobachtende Abkehr von der Kostenerstattung hin zu Vergütungsformen mit mehr Kostenverantwortung für den Arzt zielt vornehmlich auf eine Ressourceneinsparung. Da sie zugleich aber das Sorgfaltsniveau bedroht, sollte ein geeigneter Haftungsanreiz bestehen. Im vorliegenden Papier beschreibe ich unter prospektiver Vergütung sowie den realistischen Annahmen von Haftungsunsicherheit und Unterschieden zwischen den Ärzten in der Sorgfaltswaltung einen wohlfahrtsoptimalen Sorgfaltsstandard. Dieser entscheidet unter dem herrschenden Verschuldensprinzip über die Verurteilung eines Arztes zu Schadensersatz und definiert damit den Haftungsanreiz. Es erweist sich, dass der Standard in Abhängigkeit von den Eigenschaften der Ärzte, der Wahrscheinlichkeit gerichtlicher Fehlentscheidungen und der relativen gesellschaftlichen Belastung durch Fahrlässigkeit und Defensivmedizin größer oder kleiner als das Wohlfahrtsoptimum unter Sicherheit ist. Dieses Ergebnis steht im Kontrast zu Empfehlungen von Experten, die in Anbetracht eines steigenden Haftungsdrucks eine Absenkung der Sorgfaltsanforderungen befürworten.Optimally designed reimbursement and liability rules lead physicians to practice efficiently and carefully. The introduction of supply-side cost sharing in Germany and elsewhere should therefore be complemented by an appropriate liability incentive. Otherwise, resources are used efficiently but the level of care is too low. Under the assumptions of liability uncertainty and heterogeneous physicians I derive an optimal standard of due care. In deciding whether a physician acted negligently or not, the standard defines the liability threat of the negligence rule. Dependent on the distribution of physicians' types, probabilities of type one and type two errors in courts' judgments, and society's costs of negligence and defensive medicine, this second-best standard may well be above the first-best level of care. In contrast, medico-legal experts currently plead for a decrease of the standard of due care to cope with an increase of liability threat

Obesity and Undiagnosed Diabetes in the U.S.

OBJECTIVE—To study whether obese individuals, who are at higher risk for diabetes and disparities in care than nonobese individuals, are more likely to have undiagnosed diabetes

An Exploration of the Patient Lived Experience of Remission and Relapse of Type 2 Diabetes Following Bariatric Surgery

BACKGROUND: Bariatric surgery is the most effective treatment for patients with obesity and type 2 diabetes (T2DM), inducing profound metabolic changes associated with improvements in glycaemic control. In spite of the recognition of the physiological changes associated with bariatric surgery, what remains underappreciated is the patient experience of surgery to treat T2DM. OBJECTIVES: This study explored the patient experience with regard to motivations, expectations and outcomes, including remission and relapse of diabetes. METHODS: An in-depth qualitative approach was adopted, encompassing semi-structured interviews with patients (n=17) living with obesity and T2DM both pre- and postsurgery. Interpretive thematic analysis identified emergent themes using a grounded approach. RESULTS: Analysis revealed a number of themes throughout the interviews which included motivations and perceived benefits of surgery, obesity stigma and its impact on self-worth as well as perceptions of remission or relapse and the implications for sense of control. CONCLUSIONS: The motivation for undergoing bariatric surgery was driven by health concerns, namely T2DM and the desire to reduce the risk of developing diabetes-related complications. Patients highlighted social and self-stigmatisation associated with obesity and T2DM, leading to feelings of shame and an inability to seek support from family or healthcare professionals. Stigmatisation created a sense of failure and feeling of guilt for having T2DM. As a result, patients felt responsible for maintaining disease remission postoperatively and regarded the need for medication as a sign of treatment failure

Responses to gestational weight management guidance: a thematic analysis of comments made by women in online parenting forums

Background: The National Institute for Health and Clinical Excellence (NICE) published guidance on weight management in pregnancy in July 2010[1], and this received considerable press coverage across a range of media. This offered an opportunity to examine how gestational weight management guidance was received by UK women. Methods: A thematic analysis was conducted of 400 posts made in UK-based parenting internet forums in the week following the publication of the NICE guidance. This allowed us to examine the naturally occurring comments from 202 women who posted about the guidance on public forums. Results: Three main themes were identified and explored: i) Perceived control/responsibility ii) Risk perception iii) Confused messages. Conclusions: Women differed in their perceptions of the level of control that they had over being overweight with some feeling responsible and motivated to maintain a healthy lifestyle. Others felt there were multiple factors influencing their weight issues beyond their control. There were reports of feeling guilty about the impact of weight on the growing baby and experiencing significant obesity stigma from the public and health professionals. Information about the risks of overweight and obesity in pregnancy were difficult messages for women to hear, and for health professionals to deliver. Women reported being confused by the messages that they received. Health messages need to be delivered sensitively to women, and health professionals need support and training to do this. Risk information should always be accompanied with clear advice and support to help women to manage their weight in pregnancy. Keywords: internet-mediated research, gestational weight gain, parenting forums, NICE, women, views, risk perception</p

‘Do i care?’ young adults' recalled experiences of early adolescent overweight and obesity: a qualitative study

&lt;p&gt;Objective: Individual behaviour change to reduce obesity requires awareness of, and concern about, weight. This paper therefore describes how young adults, known to have been overweight or obese during early adolescence, recalled early adolescent weight-related awareness and concerns. Associations between recalled concerns and weight-, health- and peer-related survey responses collected during adolescence are also examined.&lt;/p&gt; &lt;p&gt;Design: Qualitative semi-structured interviews with young adults; data compared with responses to self-report questionnaires obtained in adolescence.&lt;/p&gt; &lt;p&gt;Participants: A total of 35 participants, purposively sub-sampled at age 24 from a longitudinal study of a school year cohort, previously surveyed at ages 11, 13 and 15. Physical measures during previous surveys allowed identification of participants with a body mass index (BMI) indicative of overweight or obesity (based on British 1990 growth reference) during early adolescence. Overall, 26 had been obese, of whom 11 had BMI99.6th centile, whereas 9 had been overweight (BMI=95th–97.9th centile).&lt;/p&gt; &lt;p&gt;Measures: Qualitative interview responses describing teenage life, with prompts for school-, social- and health-related concerns. Early adolescent self-report questionnaire data on weight-worries, self-esteem, friends and victimisation (closed questions).&lt;/p&gt; &lt;p&gt;Results: Most, but not all recalled having been aware of their overweight. None referred to themselves as having been obese. None recalled weight-related health worries. Recollection of early adolescent obesity varied from major concerns impacting on much of an individual's life to almost no concern, with little relation to actual severity of overweight. Recalled concerns were not clearly patterned by gender, but young adult males recalling concerns had previously reported more worries about weight, lower self-esteem, fewer friends and more victimisation in early adolescence; no such pattern was seen among females. Conclusion: The popular image of the unhappy overweight teenager was not borne out. Many obese adolescents, although well aware of their overweight recalled neither major dissatisfaction nor concern. Weight-reduction behaviours are unlikely in such circumstances.&lt;/p&gt