bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of a Protective Cage for an Intravascular Axial Flow Blood Pump to Mechanically Assist the Failing Fontan
Authors: Throckmorton Amy L. , Kishore Ravi A. 
Published: June 2009

AbstractCurrently, no long‐term mechanical bridge‐to‐transplant or bridge‐to‐recovery therapeutic alternative exists for failing single ventricles. A blood pump that would augment pressure in the cavopulmonary circulation is needed, and would lead to a reduction in elevated systemic venous pressure, and improve cardiac output. Thus, we are developing a collapsible, percutaneously inserted, axial flow blood pump to support the cavopulmonary circulation in adult patients with a failing single ventricle physiology. This collapsible axial flow pump is designed for percutaneous positioning. The outer protective cage will be designed with radially arranged filaments as touchdown surfaces to protect the vessel wall from the rotating components. This study examined the geometric characteristics of the protective cage of filaments and the impeller through the development and numerical analysis of 13 models. A blood damage analysis was also performed on selected geometric models to assess the probability of blood trauma. All models demonstrated an acceptable hydraulic performance by delivering 2–6 L/min at a rotational speed of 6000–10 000 rpm and generating pressure rise of 5–20 mm Hg. Expected trends in the hydraulic performance of the pump models were found. This study represents the initial first design phase of the impeller and protective cage of filaments. Validation of these flow and performance predictions will be completed in the next round of experimental testing with blood bag evaluation.
Preservation of Muscular and Elastic Artery Distensibility After an Intercontinental Cryoconserved Exchange: Theoretical Advances in Arterial Homograft Generation and Utilization
Authors: Bia Daniel , Atienza José M. , Salvucci Fernando , Zócalo Yanina , Rojo Francisco J. , García‐Herrera Claudio , Claes Els , Pérez Héctor , Craiem Damián , Lluberas Sebastián , Fernández Daniel , Laza Sebastián , Guinea Gustavo V. , Armentano Ricardo L. 
Published: June 2009

AbstractWhile the situation of tissue donation and transplantation differs between Latin American and European countries, a common problem is tissue deficiency. Hence, at present, there is a pressing need to generate alternatives so as to increase the possibilities of obtaining the requested materials. Consequently, it would be of significant interest to establish an intercontinental network for tissue exchange, to improve international cooperation, and to help patients that need tissue transplantation, and to evaluate the feasibility of using an intercontinental network for the exchange of cryopreserved arteries (cryografts), preserving the arterial distensibility and ensuring a reduced native artery–cryograft biomechanical mismatch. Distensibility was studied in ovine arteries divided into three groups: intact (in vivo tests, conscious animals), fresh control (in vitro tests immediately after the artery excision, Uruguay), and cryografts (in vitro tests of cryopreserved‐transported‐defrosted arteries, Spain). Histological studies were performed so as to analyze changes in the endothelial layer and elastic components. The comparison between fresh control and cryografts showed that neither the cryopreservation nor the exchange network impaired the distensibility, despite the expected histological changes found in the cryografts. The comparison between intact and cryografts showed that the cryografts would be capable of ensuring a reduced biomechanical mismatch. The cryopreservation and the intercontinental network designed for artery exchange preserved the arterial distensibility. It could be possible to transfer cryografts between Latin America and Europe to be used in cardiovascular surgeries and/or for tissue banking reprocessing, with basic biomechanical properties similar to those of the fresh and/or native arteries.
Simulation of Thrombus Formation in Shear Flows Using Lattice Boltzmann Method
Authors: Tamagawa Masaaki , Kaneda Hiroaki , Hiramoto Miki , Nagahama Sho 
Published: June 2009

AbstractThis article describes the prediction of index of thrombus formation in shear blood flow by computational fluid dynamics with the Lattice Boltzmann Method (LBM), applying to backward‐facing step flow, which is a simple model of shear flow in the rotary blood pumps and complicated geometry of medical fluid devices. Assuming that the blood flow is a multiphase flow composed of blood plasma and activated fibrinogen, the effects of surface tension and adhesion force to the wall were added to the LBM computational model. It was found that the thrombus formation in the backward‐facing step flow occurred just after the reattachment point and behind the step. These results corresponded to our observation results of thrombus formation. For the thrombus formation in every case of blood flow to be predicted, effects of threshold level of physical parameters such as shear rate and adhesion force (effective distance from the wall) were estimated. Moreover, it was also found that the predicted adhesion point on the wall agrees with the visualization of thrombus formation by predicting proper thresholds.
Development of a Closed Air Loop Electropneumatic Actuator for Driving a Pneumatic Blood Pump
Authors: Jeong Gi Seok , Hwang Chang Mo , Nam Kyoung Won , Ahn Chi Bum , Kim Ho Chul , Lee Jung Joo , Choi Jaesoon , Son Ho Sung , Fang Yong Hu , Son Kuk Hui , Lim Choon Hak , Sun Kyung 
Published: June 2009

AbstractIn this study, we developed a small pneumatic actuator that can be used as an extracorporeal biventricular assist device. It incorporated a bellows‐transforming mechanism to generate blood‐pumping pressure. The cylindrical unit is 88 ± 0.1 mm high, has a diameter of 150 ±  0.1 mm, and weighs 2.4 ± 0.01 kg. In vitro, maximal outflow at the highest pumping rate (PR) exceeded 8 L/min when two 55 mL blood sacs were used under an afterload pressure of 100 mm Hg. At a pumping rate of 100 beats per minute (bpm), maximal hydraulic efficiency was 9.34% when the unit supported a single ventricle and 13.8% when it supported both ventricles. Moreover, pneumatic efficiencies of the actuator were 17.3% and 33.1% for LVAD and BVAD applications, respectively. The energy equivalent pressure was 62.78∼208.10 mm Hg at a PR of 60∼100 bpm, and the maximal value of dP/dt during systole was 1269 mm Hg/s at a PR of 60 bpm and 979 mm Hg/s at a PR of 100 bpm. When the unit was applied to 15 calves, it stably pumped 3∼4 L/min of blood at 60 bpm, and no mechanical malfunction was experienced over 125 days of operation. We conclude that the presently developed pneumatic actuator can be utilized as an extracorporeal biventricular assist device.
Beneficial Effect of Preventative Intra‐Aortic Balloon Pumping in High‐Risk Patients Undergoing First‐Time Coronary Artery Bypass Grafting—A Single Center Experience
Authors: Gong Qingcheng , Xing Jialin , Miao Na , Zhao Yanyan , Jia Zaishen , Li Jiawei , Chen Yu , Gao Quanxin , Liu Anxin , Sun Zhiquan , Liu Xiaojun , Ji Bingyang 
Published: June 2009

AbstractAlthough intra‐aortic balloon pumping (IABP) has been used widely as a routine cardiac assist device for perioperative support in coronary artery bypass grafting (CABG), the optimal timing for high‐risk patients undergoing first‐time CABG using IABP is unknown. The purpose of this investigation is to compare preoperative and preventative IABP insertion with intraoperative or postoperative obligatory IABP insertion in high‐risk patients undergoing first‐time CABG. We reviewed our IABP patients' database from 2002 to 2007; there were 311 CABG patients who received IABP treatment perioperatively. Of 311 cases, 41 high‐risk patients who had first‐time on‐pump or off‐pump CABG (presenting with three or more of the following criteria: left ventricular ejection fraction less than 0.45, unstable angina, CABG combined with aneurysmectomy, or left main stenosis greater than 70%) entered the study. We compared perioperatively the clinical results of 20 patients who underwent preoperative IABP placement (Group 1) with 21 patients who had obligatory IABP placement intraoperatively or postoperatively during CABG (Group 2). There were no differences in preoperative risk factors, except left ventricular aneurysm resection, between the two groups. There were no differences in indications for high‐risk patients between the two groups. The mean number of grafts was similar. There were no significant differences in the need for inotropes, or in cerebrovascular, gastrointestinal, renal, and infective complications postoperatively. There were no IABP‐related complications in either group. Major adverse cardiac event (severe hypotension and/or shock, myocardial infarction, and severe hemodynamic instability) was higher in Group 2 (14 [66.4%] vs. 1 [5%], P < 0.0001) during surgery. The time of IABP pumping in Group 1 was shorter than in Group 2 (72.5 ± 28.9 h vs. 97.5 ± 47.7 h, P < 0.05). The duration of ventilation and intensive care unit stay in Group 1 was significantly shorter than in Group 2, respectively (22.0 ± 1.6 h vs. 39.6 ± 2.1 h, P < 0.01 and 58.0 ± 1.5 h vs. 98.5 ± 1.9 h, P < 0.005). There were no differences in mortality between the two groups (n = 1 in Group 1 and n = 3 in Group 2). Preoperative and preventative insertion of IABP can be performed safely in selected high‐risk patients undergoing CABG, with results comparable to those in patients who received obligatory IABP intraoperatively and postoperatively. Therefore, earlier IABP support as part of surgical strategy may help to improve the outcome in high‐risk first‐time CABG patients.
Treatment of Acute Renal Failure in the Intensive Care Unit: Lower Costs by Intermittent Dialysis Than Continuous Venovenous Hemodiafiltration
Authors: Farese Stefan , Jakob Stephan M. , Kalicki Robert , Frey Felix J. , Uehlinger Dominik E. 
Published: June 2009

AbstractIntermittent and continuous renal replacement therapies (RRTs) are available for the treatment of acute renal failure (ARF) in the intensive care unit (ICU). Although at present there are no adequately powered survival studies, available data suggest that both methods are equal with respect to patient outcome. Therefore, cost comparison between techniques is important for selecting the modality. Expenditures were prospectively assessed as a secondary end point during a controlled, randomized trial comparing intermittent hemodialysis (IHD) with continuous venovenous hemodiafiltration (CVVHDF). The outcome of the primary end points of this trial, that is, ICU and in‐hospital mortality, has been previously published. One hundred twenty‐five patients from a Swiss university hospital ICU were randomized either to CVVHDF or IHD. Out of these, 42 (CVVHDF) and 34 (IHD) were available for cost analysis. Patients' characteristics, delivered dialysis dose, duration of stay in the ICU or hospital, mortality rates, and recovery of renal function were not different between the two groups. Detailed 24‐h time and material consumption protocols were available for 369 (CVVHDF) and 195 (IHD) treatment days. The mean daily duration of CVVHDF was 19.5 ± 3.2 h/day, resulting in total expenditures of €436 ± 21 (21% for human resources and 79% for technical devices). For IHD (mean 3.0 ±  0.4 h/treatment), the costs were lower (€268 ± 26), with a larger proportion for human resources (45%). Nursing time spent for CVVHDF was 113 ± 50 min, and 198 ± 63 min per IHD treatment. Total costs for RRT in ICU patients with ARF were lower when treated with IHD than with CVVHDF, and have to be taken into account for the selection of the method of RRT in ARF on the ICU.
Recharging the Battery of Implantable Biomedical Devices by Light
Authors: Algora Carlos , Peña Rafael 
Published: June 2009

AbstractThis article describes a new powering system for implantable medical devices that could significantly increase their lifetime. The idea is based on the substitution of the usual implantable device battery for an electric accumulator (rechargeable battery), which is fed by the electric power generated by a photovoltaic converter inside the implantable device. Light impinges on the photovoltaic device through an optical fiber going from the photovoltaic device to just beneath the patient's epidermis. Light can enter the optical fiber by passing through the skin. A complete power‐by‐light system has been developed and tested with a real implantable pulse generator for spinal cord stimulation. The feasibility of the proposed system has been evaluated theoretically. For example, after 13 h/week of laser exposure, the lifetime of the implantable device would increase by 50%. Other combinations resulting in lifetime increases of more than 100% are also possible. So, the proposed system is now ready to take a further step forward: in vivo animal testing.
Mating status, immune defence, and multi‐parasite burden in the damselfly Coenagrion armatum
Authors: Honkavaara J. , Rantala M. J. , Suhonen J. 
Published: June 2009

AbstractImmunity and reproductive effort are both physiologically costly and often a trade‐off between these functions has been shown. In studies with damselflies, parasite load has been associated with fitness costs, such as reductions in mating success, male condition, and survival. Although each individual may be simultaneously infected by various parasite species, most studies have concentrated on the effects of a single parasite taxon. We examined natural ecto‐ and endoparasite infection levels in male Coenagrion armatum (Charpentier) (Odonata: Coenagrionidae) damselflies in relation to their mating status, fat reserves, and ability to further mount an immune response, measured as encapsulation of an experimentally introduced foreign object. Encapsulation response was lower for mated (paired) males than for single males and declined with increasing water mite abundance. Mated males had fewer water mites than single males. Male weight or fat reserves did not explain variation in encapsulation response. The number of gregarine gut parasites was not related to the level of encapsulation response and did not differ between mated and single males. However, there was a negative correlation between mite abundance and gregarine load. Our data suggest that current mite infection may compromise a male’s resistance against further infections by pathogens and parasites, and there may be a trade‐off between reproductive effort and encapsulation response in male C. armatum.
Actual Proliferating Index and p53 protein expression as prognostic marker in odontogenic cysts
Authors: Gadbail AR , Chaudhary M , Patil S , Gawande M 
Published: June 2009

Background:  The purpose of this study was to evaluate the biological aggressiveness of odontogenic keratocyst/keratocystic odontogenic tumour (KCOT), radicular cyst (RC) and dentigerous cyst (DC) by observing the actual proliferative activity of epithelium, and p53 protein expression.Methods:  The actual proliferative activity was measured by Ki‐67 Labelling Index and argyrophilic nucleolar organizing regions (AgNOR) count per nucleus. The p53 protein expression was also evaluated.Results:  Ki‐67 positive cells were observed higher in suprabasal cell layers of KCOT with uniform distribution, a few of them were predominantly observed in basal cell layer in RC and DC. The AgNOR count was significantly higher in suprabasal cell layers of KCOT. The actual proliferative activity was noted to be higher in suprabasal cell layers of KCOT. The p53 immunolabelling was dense and scattered in basal and suprabasal cell layers in KCOT. The weakly stained p53 positive cells were observed diffusely distributed in KCOT, whereas they were mainly seen in basal cell layer of RC and DC.Conclusion:  The quantitative and qualitative differences of the proliferative activity and the p53 protein expression in sporadic KCOT may be associated with intrinsic growth potential that could play a role in its development and explain locally aggressive biological behaviour. AgNOR count and p53 protein detection in odontogenic lesions can be of great consequence to predict the biological behaviour and prognosis.
Schizophrenia: genetics, prevention and rehabilitation
Authors: Olgiati Paolo , Mandelli Laura , Lorenzi Cristina , Marino Elena , Adele Pirovano , Ferrari Barbara , De Ronchi Diana , Serretti Alessandro 
Published: June 2009

Objective:Genetic factors are largely implicated in predisposing to schizophrenia. Environmental factors contribute to the onset of the disorder in individuals at increased genetic risk. Cognitive deficits have emerged as endophenotypes and potential therapeutic targets for schizophrenia because of their association with functional outcome. The aims of this review were to analyse the joint effect of genetic and environmental (G×E) factors on liability to schizophrenia and to investigate relationships between genes and cognitive endophenotypes focusing on practical applications for prevention and rehabilitation.Methods:Medline search of relevant studies published between 1990 and 2008.Results:In schizophrenia, examples of G×E interaction include the catechol-O-methyl transferase (COMT) (Val158Met) polymorphism, which was found to moderate the onset of psychotic manifestations in response to stress and to increase the risk for psychosis related to cannabis use, and neurodevelopmental genes such as AKT1 (serine-threonine kinase), brain-derived neurotrophic factor (BDNF), DTNBP1 (dysbindin) and GRM3 (metabotropic glutamate receptor 3), which were associated with development of schizophrenia in adulthood after exposure to perinatal obstetric complications. Neurocognitive deficits are recognised as core features of schizophrenia that facilitate the onset of the disorder and have a great impact on functional outcome. Neurocognitive deficits are also endophenotypes that have been linked to a variety of genes [COMT, neuregulin (NRG1), BDNF, Disrupted-In-Schizophrenia 1 (DISC1) and dysbindin] conferring susceptibility to schizophrenia. Recently, it has emerged that cognitive improvement during rehabilitation therapy was under control of COMT (Val158Met) polymorphism.Conclusion:This review could indicate a pivotal role of psychiatric genetics in prevention and rehabilitation of schizophrenic psychoses.
Safety, tolerability and efficacy of a rapid dose escalation of quetiapine in bipolar I mania: the FATIMA study
Authors: Constant Eric , Seghers Arlette , Ranalli Enio , Ryckmans Vincent , Snauwaert Phillippe , Parent Marcel , Vandenhoven Guy 
Published: June 2009

Objective:The FATIMA study (FAst TItration of quetiapine fumarate in bipolar I MAnia) evaluated the safety, tolerability and efficacy of a rapid dose escalation of quetiapine in acutely ill bipolar I patients experiencing a manic episode.Methods:In an open-label, phase II pilot study, 29 patients aged 18 years or older, hospitalised with a bipolar I manic episode, received quetiapine twice daily for 21 days. Quetiapine was administered at 200, 400, 600, then 800 mg/day on the first 4 days, with flexible dosing (400–800 mg/day) subsequently. The primary endpoint was the proportion of patient dropouts because of adverse drug reactions during the first 7 days. Secondary safety assessments included incidences of adverse drug reactions and significant changes in vital signs. Efficacy assessments included Young Mania Rating Scale (YMRS) and Clinical Global Impressions Severity of Illness (CGI-S) score changes from day 1 to day 21.Results:Twenty patients (69%) completed the study. No patients withdrew as a result of drug-related adverse events (AEs) during the first 7 days. Twenty-three patients reported 58 adverse events, and most of the adverse events were mild or moderate. No clinically relevant abnormalities in vital signs were reported. Mean YMRS and CGI-S scores decreased significantly from baseline to day 21 (p < 0.001). Response and remission rates were 78 and 70%, respectively, at the end of the study.Conclusion:Rapid dose escalation of quetiapine to 800 mg/day over 4 days was well tolerated and effective in reducing symptoms within 5 days in acutely ill bipolar I patients with a manic episode.
Upstream genetic variant nearINSIG2, influences response to carnitine supplementation in bipolar patients with valproate-induced weight gain
Authors: Doudney K , Harley JA , Pearson JF , Miller A , Aitchison A , Kennedy MA , Porter RJ , Elmslie JL , Joyce PR 
Published: June 2009

Background:The protein product ofINSIG2is involved in cholesterol and triglyceride metabolism and homeostasis. Variation at rs7566605 near the geneINSIG2has been associated with increased BMI.Objective:To evaluate the effect of rs7566605/INSIG2genotype on the ability of valproate-treated bipolar patients (BMI ≥ 25 kg/m2) to lose weight using carnitine supplementation during a 26-week lifestyle intervention study.Design:Forty-eight bipolar patients with clinically significant treatment emergent weight gain were genotyped at the rs7566605 SNP. Participants were randomised tol-carnitine (15 mg/kg/day) or placebo for 26 weeks in conjunction with a moderately energy restricted, low-fat diet. Weight and body fat percent were measured fortnightly. Waist circumference measurements and dual-energy X-ray absorptiometry were used to assess changes in body composition. Obesity-related biomarkers were measured at baseline and 26 weeks.Results:There was a significant interaction between rs7566605/INSIG2genetic status and treatment with carnitine or placebo. Carnitine had no significant effect on body composition measures in G allele homozygous patients who lost between 0.97 and 2.23 kg of fat. However C allele carriers on average gained 2.28 kg when given a placebo. Carnitine supplementation in this group enabled average weight loss of 2.22 kg of fat (p= 0.01). Approximately half of this mass was in the vital truncal compartment (p= 0.002). Bioinformatic analysis detected that the SNP lies in a highly conserved 336 bp sequence which potentially affectsINSIG2gene expression.Conclusions:C-carriers at rs7566605, possibly regulating the homeostasis geneINSIG2, lost significantly less weight in this lifestyle intervention study. This effect was reversed by carnitine supplementation.
Olfactory identification in young relatives at risk for schizophrenia
Authors: Keshavan Matcheri S. , Vora Anvi , Montrose Debra , Diwadkar Vaibhav A. , Sweeney John 
Published: June 2009

Objective:Olfactory identification deficits (OIDs) are seen in schizophrenia, but it is unclear whether they are state- or trait-related.Methods:We examined the prevalence of OIDs, as assessed by the University of Pennsylvania Smell Identification Test (UPSIT), and their correlations with prodromal symptoms in young relatives at risk for schizophrenia or schizoaffective disorder (HR-S).Results:UPSIT scores were lower in HR- S than in healthy controls, but were non-significant after covarying the effects of age, gender and IQ. OID deficits in HR-S were correlated, after covarying out the effects of age and IQ, with prodromal disorganisation.Conclusion:The potential value of OID deficits as markers of psychopathological vulnerability in young relatives at risk for schizophrenia deserves further investigation.