bluuebunny/crossref_metadata_2025_split huggingface dataset:
Turbulence Dynamics at the Shoal–Channel Interface in a Partially Stratified Estuary
Authors: Collignon Audric G. , Stacey Mark T. 
Published: January 2013

Abstract
Turbulence observations at the shoal–channel interface in South San Francisco Bay are described and analyzed in this work. Profiles of turbulent kinetic energy (TKE) shear production and dissipation rate are estimated from ADCP beam velocities over a nine-day period during winter 2009 when the estuary was partially stratified. The TKE shear production profiles are consistent with a tidally driven bottom boundary layer, except late in the ebb when shear production intensifies and the region of maximum production is located in the upper half of the water column. A simple scaling for the depth-averaged TKE shear production based on bed friction performs well except during this late ebb period when it fails to predict the peak in shear production, which suggests that a mechanism other than bottom drag drives turbulence dynamics during this period. The profiles of TKE dissipation rates also display a late ebb peak. A lateral circulation develops at the shoal–channel interface during this late ebb period, and its effects on turbulence dynamics are investigated. An analytical framework is developed to identify and quantify these effects. Four mechanisms through which the lateral circulation can impact stability are identified, and two are found to be important during the late ebb period in South San Francisco Bay: the straining of the lateral density and velocity gradients in the lateral circulation. These results suggest that the lateral circulation acts to reduce the gradient Richardson number and is driving the late ebb peak in turbulence production and dissipation.
Do former substance users with psychosis differ in their symptoms or function from non-substance users? A systematic meta-analysis
Authors: Gupta Pal , Mullin Katherine , Nielssen Olav , Harris Anthony , Large Matthew 
Published: January 2013

Objective: To compare the symptoms and function of patients with psychosis who have ceased using substances to those who have psychosis but do not have a history of substance use. Method: The databases EMBASE, MEDLINE and PsycINFO were searched for peer-reviewed publications in English reporting the characteristics of patients with psychotic illness who had stopped using substances and those who had never used substances. The searches yielded 20 articles that met the inclusion criteria. Four key outcome variables – positive symptoms, negative symptoms, depression and global function – and four other outcome measures reported in five or more studies were examined using meta-analysis. Results: Former substance-using patients were significantly younger than non-substance-using patients and were more likely to be male, but did not differ in age at onset of psychosis or in their level of education. There were no significant differences between former substance users and non-substance users in ratings of positive symptoms, negative symptoms, depression or global function. Among first-episode patients there was a trend towards former substance users having less severe depressive symptoms than non-substance users. In contrast, among non-first-episode patients, former substance users had significantly more depressive symptoms than non-substance users. In studies rated as being of higher quality, former substance users had significantly less severe positive symptoms than non-substance users. Conclusion: The absence of significant differences between the two groups suggests that a history of substance use is not a poor prognostic indicator for patients who are able to stop using substances.
Metabolite profiles in the anterior cingulate cortex of depressed patients differentiate those taking N-acetyl-cysteine versus placebo
Authors: Das Pritha , Tanious Michelle , Fritz Kristina , Dodd Seetal , Dean Olivia M , Berk Michael , Malhi Gin S 
Published: January 2013

Background: Increased oxidative stress is thought to contribute to the pathophysiology of major depressive disorder (MDD), which is in part due to diminished levels of glutathione, the primary anti-oxidant of the brain. Oral administration of N-acetyl-cysteine (NAC) replenishes glutathione and has therefore been shown to reduce depressive symptoms. Proton magnetic spectroscopy (1H-MRS) that allows quantification of brain metabolites pertinent to both MDD and oxidative biology may provide some novel insights into the neurobiological effects of NAC, and in particular metabolite concentrations within the anterior cingulate cortex (ACC) are likely to be important given the key role of this region in the regulation of affect. Objective: The aim of this study was to determine whether the metabolite profile of the ACC in MDD patients predicts treatment with adjunctive NAC versus placebo. Methods: This study was nested within a multicentre, randomized, double-blind, placebo-controlled study of MDD participants treated with adjunctive NAC. Participants ( n = 76) from one site completed the spectroscopy component at the end of treatment (12 weeks). Spectra from a single-voxel in the ACC were acquired and absolute concentrations of glutamate (Glu), glutamate-glutamine (Glx), N-acetyl-aspartate (NAA) and myo-inositol (mI) were obtained. Binary logistic regression analysis was performed to determine whether metabolite profiles could predict NAC versus placebo group membership. Results: When predicting group outcome (NAC or placebo), Glx, NAA and mI were a significant model, and had 75% accuracy, while controlling for depression severity and sex. However, the Glu, NAA and mI profile was only predictive at a trend level, with 68.3% accuracy. For both models, the log of the odds of a participant being in the NAC group was positively related to NAA, Glx and Glu levels and negatively related to mI levels. Conclusion: The finding of higher Glx and NAA levels being predictive of the NAC group provides preliminary support for the putative anti-oxidative role of NAC in MDD.
Further evidence for slow binocular rivalry rate as a trait marker for bipolar disorder
Authors: Vierck Esther , Porter Richard J , Luty Sue E , Moor Stephanie , Crowe Marie T , Carter Janet D , Inder Maree L , Joyce Peter R 
Published: January 2013

Objective: Binocular rivalry refers to a situation where contradictory information is presented simultaneously to the same location of each eye. This leads to the alternation of images every few seconds. The rate of alternation between images has been shown to be slower in euthymic participants with bipolar disorder than in healthy controls. The alternation rate is not uniformly slowed in bipolar disorder patients and may be influenced by clinical variables. The present study examined whether bipolar disorder patients have slower alternation rates, examined the influence of depression and explored the role of clinical variables and cognitive functions on alternation rate. Method: Ninety-six patients with bipolar disorder and 24 control participants took part in the study. Current mood status and binocular rivalry performance were analysed with nonparametric tests. A slow and a normal alternation group were created by median split. We subsequently explored the distribution of several clinical variables across these groups. Further, we investigated associations between alternation rate and various cognitive functions, such as visual processing, memory, attention and general motor speed. Results: The median alternation rate was significantly slower for participants with bipolar disorder type I (0.39 Hz) and for participants with bipolar spectrum disorder (0.43 Hz) than for control participants (0.47 Hz). Depression had no effect on alternation rate. There were no differences between participants with bipolar disorder type I and type II and in regard to medication regime and predominance of one rivalry image. There were also no differences in regard to the clinical variables and no significant associations between alternation rate and the cognitive functions explored. Conclusion: We replicated a slowing in alternation rate in some bipolar disorder participants. The alternation rate was not affected by depressed mood or any of the other factors explored, which supports views of binocular rivalry rates as a trait marker in bipolar disorder.
Babies Need Healthy Moms
Authors: Frazzitta Marie A. , Anderson Michele , Egan Elizabeth 
Published: January 2013

Purpose Healthy Babies Need Healthy Moms (HBNHM) is an innovative education program that combines the recommended 2-hour postpartum oral glucose tolerance test (OGTT) with diabetes prevention education for women who had gestational diabetes mellitus. During the class, the 2-hour OGTT is performed, and in the time between venipunctures, the women participate in group education focused on evidence-based diabetes prevention strategies that promote healthy family nutrition and lifestyle behavior, importance of preconception care for subsequent pregnancies, and the need for follow-up care for women who screen positive for abnormal glucose levels. The purpose of this article is to describe this model to encourage replication in other diabetes programs. Conclusion The HBNHM program is a low-budget education program that provides postpartum OGTT screening for women who had gestational diabetes mellitus during their pregnancies while simultaneously offering education designed to improve future outcomes. For those women whose screening is positive for overt diabetes or prediabetes, the educational strategies are directed at encouraging follow-up care. For those patients who have normal screening results, the program is designed to help the patient prevent the future development of type 2 diabetes. Preconception counseling is included in an effort to improve outcomes in future pregnancies and provide patients with the tools needed to help enhance the health of their families.
Practical techniques Vacuum-assisted venous return in pediatric cardiopulmonary bypass
Authors: Berryessa Richard , Wiencek Robert , Jacobson John , Hollingshead Dan , Farmer Ken , Cahill George 
Published: January 2013

Vacuum-assisted venous return (VAVR) has been reported to offer benefits for adults undergoing cardiopulmonary bypass (CPB), such as improved venous return, lowering priming volume (by eliminating the need to prime the venous line), and the use of smaller venous cannulae. All these benefits would be of particular value in pediatric perfusion because of the unique challenges of these smaller patients and the relatively large components of the CPB circuit. We have been using VAVR in children since the early summer of 1998 after we became comfortable with the technique and convinced of its efficacy in adults. Ours is a medium-sized pediatric caseload of slightly more than 100 CPB cases per year. With that caseload, it is most effective for us to minimize the inventory of different sizes of disposables used. We have opted for an oxygenator/reservoir that has a maximum flow of 4 liters with a priming volume of about 1 liter. We have been unhappy with the large prime volume in infants and earlier, in 1997-1998, were using a smaller prime oxygenator/reservoir until it was recalled. Faced again with a larger priming volume in the infants, we decided to try vacuum to decrease hemodilution and to evaluate other possible benefits. Through the use of VAVR, we have been able to decrease our priming volume, use smaller venous cannulae, and have more consistent return while experiencing no adverse effects of VAVR in our pediatric cardiac surgery patients.
Oxygen consumption, carbon dioxide production and lactic acid during normothermic cardiopulmonary bypass
Authors: Engoren Milo , Evans Michael 
Published: January 2013

The objective of this study was to measure oxygen consumption, carbondioxide production and lactic acid levels during normothermic cardiopulmonary bypass. A prospective study was undertaken in a tertiary care community hospital, involving 20 adults undergoing cardiopulmonary bypass with prolonged (>65 min) crossclamping of the aorta. O2 consumption, CO2 production, hemoglobin and lactic acid levels were measured 5, 35 and 65 min after crossclamping of the aorta. O2 consumption was 79.7 ± 14.5, 78.8 ± 15.4 and 81.5 ± 14.1 ml/min/m2 at 5, 35 and 65 min after crossclamping the aorta. CO2 production was 61.8 ± 42.9, 60.6 ± 26.3 and 62.2 ± 35.9 ml/min/m2 at the same times. Lactic acid levels were 1.6 ± 0.5 mM/dl at all three times and did not correlate with O2 consumption or CO2 production. In conclusion, although oxygen consumption was low, there was no evidence of abnormal lactate or anaerobic metabolism to suggest tissue ischemia.
Simple modified ultrafiltration
Authors: Myers Gerard J , Leadon Richard B , Mitchell Lance B , Ross David B 
Published: January 2013

After reviewing all available methods of modified ultrafiltration (MUF), an attempt was made to develop a more simplified approach to this beneficial method of post-bypass fluid removal by withdrawing blood from the right atrium and reinfusing into the aortic cannula (venoarterial). The simplicity of operation, ease of setup and analysis of hemoglobin, hematocrit, total proteins and colloid osmotic pressure, and fluid removed were examined in 12 consecutive neonatal and pediatric patients undergoing cardiac surgery. Results indicate that this simplified modified ultrafiltration (SMUF) is comparable to all other methods of MUF by achieving dramatic improvements in all parameters measured. In addition, SMUF provides the perfusionist with the ability to run conventional ultrafiltration throughout the bypass procedure, using this one circuit design. As well as finding the learning curve for SMUF to be very short, this method was found to be superior in its simplicity of operation, ease of setup, reduced risk of complications and acceptance by the surgeon and anesthetist.
Assembly of the Heparin Removal Device for patients with suspected adverse reaction to protamine sulphate
Authors: Jegger D , Tevaearai H T , Horisberger J , Mueller X M , Seigneuil I , Pierrel N , Boone Y , von Segesser L K 
Published: January 2013

Protamine sulphate is routinely used after cardiopulmonary bypass (CPB) to restore the patient’s baseline coagulatory state. However, adverse reactions are encountered, and alternative means to neutralize heparin are, therefore, necessary. The Heparin Removal Device (HRD) constitutes an extracorporeal circuit that allows ex vivo deheparinization by mean of a polycationic ligand that binds heparin molecules. This paper presents the setup of the HRD circuit. It is illustrated by the report of a 68-year-old man with a known severe crustacean allergy. The patient (78 kg, 170 cm) was admitted for elective coronary artery bypass graft surgery. It was decided that the HRD would be used as a precaution in order to avoid the risks of using protamine sulphate. The CPB time and aortic crossclamp time were 70 and 40 min, respectively. At the end of CPB, the device was inserted and processing started. Activated coagulation time values were monitored over a 130 min period and diminished from 480 to 300 s after 45 min, 220 s after 90 min, and settled at 150 s. Haemostasis was acceptable and processing stopped. The operation was terminated and the patient transferred to the intensive care unit. Clinical evolution was excellent, with minimal postoperative bleeding. The HRD presents an alternative to protamine sulphate when this drug is contraindicated for a certain patient population who might have a suspected, known or emergency adverse reaction.
Investigation and quantification of the blood trauma caused by the combined dynamic forces experienced during cardiopulmonary bypass
Authors: Mulholland J W , Massey W , Shelton J C 
Published: January 2013

Blood is exposed to various dynamic forces during cardiopulmonary bypass (CPB). Understanding the damaging nature of these forces is paramount for research and development of the CPB circuit. The object of this study was to identify the most damaging dynamic non-physiological forces and then quantify this damage. A series of in vitro experiments simulated the different combinations of dynamic forces experienced during CPB while damage to the blood was closely monitored. A combination of air interface ( a) and negative pressure ( P) caused the greatest rate of change in plasma Hb (Δp Hb) (4.94 10-3 mg/dl/s) followed by negative pressure and then an air interface. Shear stresses, positive pressures, wall impact forces and a blood-nonendothelial surface caused the least damage (0.26 10-3 mg/dl/s). An air interface showed no threshold value for blood damage, with the relationship between the size of the interface and the blood damage modelled by a second-order polynomial. However, negative pressure did exhibit a threshold value at -120 mmHg, beyond which point there was a linear relationship. Investigating the reasons for the increased blood trauma caused by the low-pressure suction (LPS) system makes it clear how research into minimizing or completely avoiding certain forces must be the next step to advancing extracorporeal technology.
Anti-inflammatory pre-treatment and the resultant effects of interleukin-10: adjuncts to multi-therapeutical strategies
Authors: Fernando Roldan , Chan Richard 
Published: January 2013

With the advent of off-pump coronary bypass surgery, there is increasing demand for research in attenuating the deleterious effects of cardiopulmonary bypass (CPB). An improved understanding of the systemic inflammatory response syndrome (SIRS) has distinguished which areas of components have the most adverse effects and which are, in fact, anti-inflammatory. This classification of inflammatory components allows strategic treatment for those likely to cause the most clinically significant ‘effect’, suitably termed ‘effectors’. This article will identify current methods in treating ‘effectors’, as well as those components having anti-inflammatory effects. This article selectively features certain inflammatory components by: (1) grouping them as being ‘mediators’ or ‘effectors’; (2) relating them to interleukin-10 (IL-10) and treatments potentiating anti-inflammatory effects; (3) summarizing their mechanisms of action; (4) recognizing the time periods during bypass exhibiting peak levels; and (5) investigating current treatment methods and identifying their significance to ‘effectors’. A literature search in MEDLINE was performed, featuring articles of the English-language within the past 5 years. Because of the characteristic of having interlinked multi-component cascades, it is evident that treating SIRS with a one-dimensional method would be inadequate. This article not only confirms the importance of a multi-factorial therapeutic approach, but also targets the inflammatory components having the highest potential for causing direct tissue damage, known as ‘effectors’. In addition, previous studies have found IL-10 to have ‘regulatory effects’ during periods of excessive pro-inflammatory stimuli. These findings may arouse new ideas in exploring the area of anti-inflammatory cytokines. In fact, future treatments may suggest a new classification featuring ‘mediators’, ‘effectors’, and ‘regulators’.
Five-year clinical experience with Abiomed BVS 5000 as a ventricular assist device for cardiac failure
Authors: Dekkers Renè J , FitzGerald Daniel J , Couper Gregory S 
Published: January 2013

Mechanical support for the failing heart has interested and challenged cardiac specialists for decades. In the United States alone, there are close to 375 000 cardiac surgical procedures performed each year, and, despite the recent advances in myocardial protection, surgical techniques, intra-aortic balloon therapy and maximal pharmacological support, postoperative ventricular dysfunction continues to occur in 0.5-1.0% of all patients undergoing cardiac surgery. This retrospective review describes our 5-year clinical experience at the Brigham and Women's Hospital with the Abiomed BVS 5000 as a means of ventricular support. During the period of 1994 to present, 7428 cardiac surgical operations were performed at our institution. The Abiomed BVS 5000 has been implanted in 47 patients exhibiting ventricular failure. There were 38 patients in the bridge-to-recovery group and nine patients in the bridge-to-transplantation group. Twenty-five patients (66%) in the bridge-to-recovery group were weaned and 16 patients (42%) went on to discharge. In the bridge-to-transplantation group, one patient actually recovered myocardial function and one expired on the device. The remaining seven patients (77%) underwent cardiac transplantation with post-transplant survival at 66%. Overall, patients were supported in the isolated left ventricular mode (28%), in the biventricular mode (45%) and in the isolated right ventricular mode (28%). The Abiomed BVS 5000 has been shown to be a safe and simple cardiac support system with no mechanical failure. Our experience shows that a substantial number of patients suffering from ventricular failure will benefit from the use of this device. The results also justify the use of this device in groups of patients other that of postcardiotomy ventricular failure.
Significant reduction of air microbubbles with the dynamic bubble trap during cardiopulmonary bypass
Authors: Schönburg M. , Urbanek P. , Erhardt G. , Kraus B. , Taborski U. , Mühling A. , Hein S. , Roth M. , Tiedtke HJ , Klövekorn WP 
Published: January 2013

Air microbubbles mostly occur unnoticed during cardiopulmonary bypass and are predominantly responsible for serious postoperative psycho- neurological dysfunction. A dynamic bubble trap (DBT), which removes air microbubbles from the arterial blood, was tested in a clinical study. The aim was to evaluate the efficiency of microbubble removal under clinical conditions. As blood passes through the DBT, which is placed in the arterial line between the arterial filter and arterial cannula, it is converted into a rotating stream. The bubbles are directed to the centre of the blood flow and are collected in the distal end of the DBT, from where they are returned to the cardiotomy reservoir. Doppler ultrasonography was used to detect the microbubbles before and after the DBT, and also the number of high- intensity transient signals (HITS) in the right and left middle cerebral artery during extracorporeal circulation. A significant reduction of microbubbles in the arterial line (3990 before DBT, 537 after, p < 0.001) and HITS in the brain (51 in the DBT group, 77 in the placebo group, p = 0.04) was measured.