bluuebunny/crossref_metadata_2025 huggingface dataset:
Heparin‐coated Cardiopulmonary Bypass Circuits in Coronary Bypass Surgery
Authors: Horimoto Hitoshi , Kondo Keiichiro , Asada Kunio , Sasaki Shinjiro
Published: November 2008

Abstract: Cardiopulmonary bypass (CPB) is a nonphysiologic environment for an organism. The damage of blood components may also lead to organ dysfunction, sometimes recognized as postperfusion syndrome. One possible way to diminish the risk of these complications would be to reduce the thorombogenicity and to improve the biocompatibility of the artificial surfaces by using a heparin‐coated CPB circuit. In this study, we compared a heparin‐coated CPB circuit with a noncoated CPB circuit in terms of biocompatibility in 20 patients undergoing elective coronary bypass surgery. We employed a Dura‐flo II (n = 10) as a heparin‐coated CPB circuit and a Univox IC (n = 10) as control subjects. Ten patients (Group C) were operated on using the heparin‐coated CPB circuit. A total of 10 patients were given heparin in a reduced dose (2.0 mg/kg), and additional heparin was given if the activated clotting time (ACT) was below 400 s. The control group also included 10 patients (Group NC), who were operated on with noncoated devices. They received 2.5 mg/kg of heparin, and additional heparin was given if the ACT was below 450 s. All patients had normal coagulation parameters and did not receive blood transfusion. We measured complement activation levels (C3a, C4a), platelet count, thrombin‐antithrombin III complex levels, D‐dimer levels, and ACT during CPB and respiratory index postoperatively. The concentration of C3a in group NC was significantly higher than that in group C. Platelet reduction in group NC was significantly greater than that in group C. There were no significant differences in the remaining parameters between the 2 groups. We concluded that heparin‐coated CPB circuits improved biocompatibility by reducing complement activation and platelet consumption and enabled us to reduce the dose of heparin required for systemic heparinization.
Proposal of a New Auditory Nerve Stimulation Method for Cochlear Prosthesis
Authors: Miyoshi Shigeki , Iida Youhei , Shimizu Shunji , Matsushima Jun‐ichi , Ifukube Tohru
Published: November 2008

Abstract: The stimulation electrodes of cochlear implants are covered by a lymph liquid with high electrical conductivity, which causes the transmitted information to be reduced by channel interaction. Even if this problem were solved, the stimulation regions may be discrete; therefore, there may be regions in which the electrode array cannot stimulate selectively. To solve these problems, we proposed a new auditory nerve stimulation method which we call the tripolar electrode stimulation method for cochlear implants. Our method stimulates using 3 adjacent electrodes selected from among the electrodes of the electrode array. The center electrode receives the currents emitted from the electrodes on both sides. We conducted animal experiments using this method. On the basis of the results we obtained, we concluded that our method may succeed in narrowing the stimulation region and continuously moving the stimulation site.
Surgical Results of Tympanoplasty with Hokudai‐Shaped Partial and Total Ossicular Replacement Prostheses
Authors: Sakai Noboru , Asai Toshiyuki , Matsushima Jun‐ichi , Kokubun Takehiko , Kurihara Hideo , Koichi Ken‐ichi , Inuyama Yukio , Terayama Yoshihiko
Published: November 2008

Abstract: The surgical results of tympanoplasty using a ceramic partial ossicular replacement prosthesis (PORP) or a ceramic total ossicular replacement prosthesis (TORP) were analyzed. The present study included 25 ears in 22 patients who underwent tympanoplasty between December 1986 and September 1994 and were followed up for more than 6 months postoperatively. Because the ceramic prosthesis was extruded from 2 of the 25 ears, the surgical results in the other 23 ears were analyzed. Surgical results were assessed according to a criterion that permits comparison with data from around the world. The criterion considers a postoperative air‐bone gap within 20 dB as a success. According to this criterion, the success rate was 90.9% for PORP, 50.0% for TORP, and 69.6% in total. These results are comparable with those found at other centers.
Metabolic Acidosis in Hemodialysis Patients: A Study of Prevalence and Factors Affecting Intradialytic Bicarbonate Gain
Authors: Sepandj F. , Jindal K. , Kiberd B. , Hirsch D.
Published: November 2008

Abstract The correction of uremic acidosis is one of the goals of hemodialysis; however, despite acceptable hemodialysis protocols, metabolic acidosis remains a common problem. The prevalence of acidosis and significance of factors affecting bicarbonate flux during hemodialysis were studied. A cohort of 70 stable patients receiving high‐efficiency hemodialysis for at least 4 months was studied prospectively over a 1‐year period. Twenty patients (28%) had a mean predialysis serum bicarbonate of less than 21 mEq/L. The patients with or without metabolic acidosis had similar mean net ultrafiltration and percent ultrafiltration, but acidotic patients had a higher percent increase in bicarbonate during hemodialysis (35 ± 12 versus 27 ± 10 [p = 0.008]). The latter suggests an increased net daily acid gain in patients with metabolic acidosis (1.19 ± 0.32 mEq/kg versus 1.05 ± 0.35 mEq/kg [p = 0.04]). A review of factors affecting intradialytic bicarbonate gain showed that predialysis serum bicarbonate (diffusive gradient) was the most significant with a demonstrated linear relationship between these two variables (R2 0.51). The role of dialysance and blood flow, assessed together using percent urea reduction, was minor as was the effect of ultrafiltration. At our level of dialysis delivery, prevalence of metabolic acidosis is low, and dialysis‐related factors do not contribute to the persistence of metabolic acidosis. Net daily acid gain was higher in acidotic patients and accounts for the long‐term maintenance of metabolic acidosis. For individual dialysis treatments, the diffusive gradient is the most important determinant of bicarbonate gain, with only a minor role being demonstrated for percent urea reduction and ultrafiltration rate.
Use of an Integrated Sideport for Diagnosis and Management of Decreased Flow Rates in a Programmable Implanted Insulin Delivery System
Authors: Scavini Marina , Reich Sanford , Philip Eaton R. , Arthur Charles M. , Dunn Fredrick L.
Published: November 2008

Abstract The aim of this study was to develop procedures for the diagnosis and nonsurgical management of decreased insulin flow in an implantable programmable pump for long‐term intraperitoneal or intravenous insulin delivery featuring a sideport. Patency of the catheter lumen was tested by measuring the time needed for sideport pressure to decrease by 50% after the injection of 0.1 ml of buffer solution. Pumping unit performances were assessed by measuring the volume of pump pulses after diverting the pump flow at the sideport. A catheter flush with buffer solution through the sideport was effective in clearing 79% of intraperitoneal and 84% of intravenous catheter occlusions. Washing the pumping unit with an alkaline solution after diverting pump flow at the sideport was effective in dissolving insulin aggregates inside the pumping unit and in restoring normal pump flow. These procedures were associated with a 1.3% rate of hypoglycemic episodes.
Effects of Heparin Coating of Cardiopulmonary Bypass Circuits on In Vitro Oxygen Free Radical Production During Coronary Bypass Surgery
Authors: Bozdayi Mithat , Borowiec Jan , Nilsson Leif , Venge Per , Thelin Stefan , Hansson Hans‐Erik
Published: November 2008

Abstract During cardiopulmonary bypass (CPB) oxygen free radicals (OFR) are formed, which can mediate reactions damaging tissue components. Blood contact with artificial surfaces during CPB leads to an activation of leukocytes, which are one of the sources of the OFR. Heparin coating of the CPB circuit reduces granulocyte activation. In the present study, the heparin‐coated circuits with noncoated cardiotomy reservoirs (Group HC) were compared with noncoated, otherwise similar CPB sets (Group C). In each group, 8 patients were operated on for coronary revascularization. The release of granulocyte granule proteins myeloperoxidase (MPO) and lac‐toferrin (LF) was evaluated. Production of OFR in the whole blood and in the granulocyte suspension were measured by chemiluminescence (CL). In both groups the whole blood CL declined during CPB. The whole blood CL induced by serum‐opsonized zymosan, when enhanced by luminol, was significantly lower in Group HC at 45 min after CPB start (68 ± 6% of initial values in Group HC vs. 87 ± 6% in Group C, mean ± SEM) and 30 min after protaminization (54 ± 6% of initial values in Group HC vs. 72 ± 6% in Group C, mean ± SEM), and CL was significantly higher in Group HC at CPB end (83 ±5% of initial values in Group HC vs. 67 ± 5% in Group C, mean ± SEM) when enhanced by lucigenin. CL of isolated granulocytes showed no significant differences between the groups. Release of MPO at CPB end and of LF 45 min after start of CPB and at CPB end were significantly lower in the heparin‐coated CPB circuits.
Sweep Gas Flowrate and C02 Exchange in Artificial Lungs
Authors: Federspiel William J. , Haulert Brack G.
Published: November 2008

Abstract A simple analysis and graphic result are presented for characterizing the dependence of CO2 exchange on the sweep gas (ventilating gas) flowrate in artificial lungs. The analysis requires no knowledge of the device‐specific mass transfer characteristics of an artificial lung, nor does it require detailed mathematical modeling or computer simulation. Rather, it uses appropriate normalization to establish generic features of the gas flow dependency of CO2 exchange that are applicable to all artificial lung devices. Principal results are that the transition from relatively gas flow‐sensitive to gas flow‐insensitive CO2, exchange occurs at sweep gas flowrates of approximately 40–60 times the CO2 exchange rate. Achieving a CO2 exchange rate within 85% of maximal (for a given oxygenator and blood‐side conditions) requires a sweep gas flowrate of no less than approximately 50 times the nominal CO2 exchange rate. When the sweep gas flowrate is less than 20 times the CO2 exchange rate, CO2 exchange is highly gas flow dependent and less than one‐half the maximal possible rate.
Nonlinear Mathematical Analysis of the Hemodynamic Parameters During Left Ventricular Assistance with Oscillated Blood Flow
Authors: Yambe Tomoyuki , Kobayashi Shin‐ichi , Sonobe Taro , Naganuma Shigeru , Nanka Shun‐suke , Hashimoto Hiroyuki , Yoshizawa Makoto , Tabayashi Kouichi , Takayasu Hideki , Takeda Hiroshi , Nitta Shinichi
Published: November 2008

Abstract: For the development of a totally implantable ventricular assist system (VAS), we have been developing the vibrating flow pump (VFP), which can generate oscillated blood flow with a relatively high frequency (10–50 Hz) for a totally implantable system. In this study, effects of left ventricular assistance with this unique oscillated blood flow were analyzed by nonlinear mathematics for evaluation as the entire circulatory regulatory system, not as a separate part of the system. Left heart bypasses using VFPs from the left atriums to the descending aortas were performed in chronic animal experiments using healthy adult goats. Electrocardiogram (ECG), arterial blood pressure, VFP pump flow, and flow of the descending aorta data taken while the goats were awake were recorded in the data recorder and analyzed in the personal computer system through the AD convertor. Using nonlinear mathematics, time series data were embedded into the phase space, and the Lyapunov numerical method, fractal dimension analysis, and power spectrum analysis were performed to evaluate the nonlinear dynamics. During left ventricular assistance with the VFP, Mayer wave fluctuations were decreased in the power spectrum, the fractal dimension of the hemodynamics was significantly decreased, and peripheral vascular resistance was significantly decreased. These results suggest that nonlinear dynamics, which mediate the cardiovascular dynamics, may be affected during LV bypass with oscillated flow. Decreased power of the Mayer wave in the spectrum caused the limit cycle attractor of the hemodynamics and decreased the peripheral resistance. Decreased sympathetic discharges may be the origin of the decreased Mayer wave and fractal dimension. These nonlinear dynamical analyses may be useful to design the optimal VAS control.
Wireless Monitoring and Control for Implantable Rotary Blood Pumps
Authors: Mussivand Tofy , Hum Albert , Holmes Kevin S. , Keon Wilbert J.
Published: November 2008

Abstract: A wireless biotelemetry system for the transfer of digital data through intact skin and tissue has been developed to provide a safe and noninvasive means of communication between implanted medical devices and the outside of the body. The system utilizes 2 miniature infrared transmitter/receiver modules. Data are transmitted through intact skin and subcutaneous tissue on an 890 nm infrared carrier signal. The system has been evaluated in human cadavers and during in vivo implantation of artificial hearts and ventricular assist devices for durations of up to % h. Acceptable data transfer (error rate <10‐5) through a typical tissue thickness of 5–25 mm has been demonstrated. The ability to monitor and control a device from a remote site using public communication systems such as telephone lines and asynchronous transfer mode (ATM) systems has also been demonstrated. Design optimization is currently ongoing In preparation for clinical utilization with artificial heart systems and other implant‐able devices (such as rotary blood pumps).
Hemolytic Effect of Surface Roughness of an Impeller in a Centrifugal Blood Pump
Authors: Takami Yoshiyuki , Nakazawa Tadashi , Makinouchi Kenzo , Tayama Eiki , Glueck Julie , Benkowski Robert , Nosé Yukihiko
Published: November 2008

Abstract: The present study investigates how the surface roughness of an impeller affects hemolysis in the pivot bearing supported Gyro C1E3 pump. This study focuses on particular areas of the impeller surface in the impeller type centrifugal pump. Seven Gyro C1E3 pumps were prepared with smooth surface housings and different impeller parts with different surface roughnesses. The vanes, top side, and backside of the impeller were independently subjected to vapor polishing, fine sand blasting, or coarse sand blasting to produce three different grades of surface roughness. These surfaces were then examined by a surface profile instrument. Using these pumps with different impellers, in vitro hemolysis tests were performed simulating cardiopulmonary bypass (5 Wmin, 350 mm Hg). The findings of this study conclusively proved that surface roughness of the back side of the impeller has the greatest effect on hemolysis, followed by the top side and then the vanes. The following are reasons for these findings. First, the shear rate may be greater on the back side than on the top side because of the smaller gap between the back and the housing and the greater relative speed against the impeller. Second, the fluid beneath the impeller may have a longer exposure time because there is little chance for the fluid to mix beneath the impeller. Third, the shear rate may be greater on the top side of the impeller than on the vanes because a vortex formation occurs behind the vanes.
Evaluation of Hemolysis in a Pulsatile Assist Device for Centrifugal Pump
Authors: Iwaya Fumio , Igari Tsuguo , Hoshino Shunichi , Hikichi Hitoshi
Published: November 2008

Abstract: To evaluate the blood trauma caused by a new device for producing a pulsatile flow of the centrifugal pump, the pulsatile assist device for the centrifugal pump (PAD‐CP) that we have developed, a hemolysis study was performed in vitro and in animal experimentation. For the in vitro testing, 2 identical sets of hemolysis test circuits were prepared with 2,400 ml of bovine blood. The 2 circuits were pumped simultaneously. Plasma total hemoglobin levels were less than 40 mg/dl after 3 h, under a pump flow of 2 L/min. Hemolysis increased to a severe level after 4 h of 4 L/min pump flow. The cause of this hemolysis was thought to be a vibration of the circuit because of incomplete compression of the polyurethane tube in the PADCP. Five adult sheep (average body weight, 47 kg) were used for in vivo evaluation of hemolysis. Hemolysis was less than 30 mg/dl of plasma hemoglobin after 4 h of open chest extracorporeal circulation with 3.0–3.6 Limin of flow rate using the PAD‐CP. Other hematologic changes after PAD‐CP driving were within normal limits. We conclude that the PAD‐CP has proven to have possible clinical applications.
The Method for Keeping Low Perfusion Flow Weaning from Centrifugal Pumps: An Evaluation of Hemolysis in the Circulator Units
Authors: Hachiro Yoshikazu , Morishita Kiyofumi , Ito Toshiro , Sakata Junichi , Baba Toshio , Tsukamoto Masaru , Abe Tomio
Published: November 2008

Abstract: Currently, the clinical application of extracor‐poreal and assisted circulation using centrifugal pumps is becoming popular. However, a problem in the use of centrifugal pumps is the difficulty in controlling the flow rate when it is a low range. Although we have been controlling the flow rate with a control unit that simply squeezes the blood outlet tube from the outside, hemolysis resulting from turbulent flow in the tube was discovered. Therefore, this control procedure was evaluated experimentally. Two groups were tested as follows: in Group A (n = 10), the tube was squeezed from the outside using the control unit, and in Group B (n = lo), no control unit was used. Blood in each circuit was circulated at 1,500 rpm, and the flow rate was controlled to 250 ml/min using the control unit for Group A. Time‐course changes of lactate dehydrogenase (LDH) and free hemoglobin in the blood were measured during 8 h of circulation. There were no significant differences between the 2 groups in the mean values of LDH and free hemoglobin. Therefore, the present low flow rate control provided by the control unit makes it appear to be a simple and useful apparatus for controlling blood circulation using centrifugal pumps.
Development of a Novel Centrifugal Pump: Magnetic Rotary Pump
Authors: Naganuma Shigeru , Yambe Tomoyuki , Sonobe Taro , Kobayashi Shin‐ichi , Nitta Shin‐ichi
Published: November 2008

Abstract: The rotational axis of the centrifugal pump has some associated problems such as blood destruction and sealing between the axis and pump housing. To improve upon these deficits we have developed a new type of blood pump, the magnetic rotary pump (MRP). The MRP has an original design with no rotational axis and no impellers. We made a prototype MRP and examined its hemodynamics in mock circulation. The prototype MRP flow rate is only 1.0 L/min with an afterload of 30 mm Hg, and we have made some modifications in the size and drive mechanisms from these results. The modified MRP can achieve high flow rates and rotational speeds (6.0 L/min with an after‐load of 100 mm Hg, 2,000 rpm) in a mock circuit, and the modified MRP was used for left heart assistance in an acute animal experiment. The MRP could maintain the hemodynamics of an anesthetized adult goat. These results suggest that the MRP needs to be improved in several areas, but the MRP may be useful as a blood pump.
Comparison of the Gyro C1E3 and BioMedicus Centrifugal Pump Performances During Cardiopulmonary Bypass
Authors: Nakazawa Tadashi , Takami Yoshiyuki , Makinouchi Kenzo , Gay Joseph , Taylor Deborah , Ueyama Keishi , Ohashi Yukio , Kawahito Koji , Tayama Eiki , Glueck Julie , Nosé Yukihiko
Published: November 2008

Abstract: The compact eccentric inlet port (ClE3) centrifugal blood pump was developed as a cardiopulmonary bypass (CPB) pump. The C1E3 pump incorporated a seal‐less design with a blood stagnation free structure. The pump impeller was magnetically coupled to the driver magnet in a sealless manner. To develop an atraumatic and antithrombogenic centrifugal pump without a shaft seal junction, a double pivot bearing system was introduced. Recently, a mass production model of the C1E3 was fabricated and evaluated. The ratio of the normalized index of hemolysis (NIH) of the C1E3 was 0.007 g/ 100 L, in comparison to the NIH of the BP‐80, 0.018 g/ 100 L, each in a CPB condition of 5 Limin against 325 mm Hg. Both pumps were compared in identical in vitro circuits. To further evaluate the pumps during cardio pulmonary bypass for reliability and function, 6 h of CPB was performed on each of 8 bovines using either the C1E3 or BP‐80 centrifugal pump. The BP‐80 and C1E3 provided pump flows of 5MO ml/kg/min without incident. The hemodynamics were stable, and the hematology and biochemistry data were within normal ranges. There were no statistically significant differences between the 2 groups. Concerning the plasma free hemoglobin values. a mass production model of the C1E3 pump had the same hemolysis levels as the BP‐80. Our preliminary studies reveal that the C1E3 pump is reliable. Also, the C1E3 will satisfy clinical requirements as a cardiopulmonary bypass pump.
Recent Experience of Integrated Myocardial Management: The Newest Strategy for Myocardial Protection
Authors: Qkamoto F. , Sugawara H. , Minatoya Y. , Adachi A. , Sakai K. , Shimoyama Y. , Tanimura H.
Published: November 2008

Abstract: From April 1994 until June 1996, we exclusively utilized the integrated myocardial management (IMM) proposed by Buckberg et al. at UCLA. Two hundred sixtytwo consecutive patients undergoing open heart surgery at our hospital were divided into 2 groups, the non‐IMM (n = 49. from July 1993 until March 1994) and the IMM (n = 213, from April 1994 until June 1996) groups. Although many older and more severely ill patients were treated with IMM, acceptable clinical outcomes with comparable safety and efficiency were obtained. Shorter durations of total cardiopulmonary bypass (CPB) and aortic cross‐clamping (AXC) were needed in the IMM group despite there being many more procedures undertaken during a single cross‐clamp period.
Clinical Evaluation of Pulsatile Flow Mode of Terumo Capiox Centrifugal Pump
Authors: Nishida Hiroshi , Uesugi Hideyuki , Nishinaka Tomohiro , Uwabe Kazuhiko , Aomi Shigeyuki , Endo Masahiro , Koyanagi Hitoshi , Oshiyama Hiroaki , Nogawa Atsuhiko , Akutsu Tetsuzo
Published: November 2008

Abstract: The Terumo Capiox centrifugal pump system possesses an automatic priming function in which the motor repeatedly stops and runs intermittently to eliminate air bubbles in the circuit through the micropores of the hollow‐fiber membrane oxygenator. By modifying this mechanism, we have developed a pulsatile flow mode. In this mode, maximum and minimum pump rotational speeds can be independently set every 20 rpm in the range of 0 to 3,000 rpm. The duration of the pump run at maximum and minimum speeds can also be independently set every 0.1 s in the range of 0.2 to 15 s. In a clinical trial, after obtaining the desired flow rate, 2.4 L/min/m2in nonpulsatile flow mode, a pulsatile flow mode of 60 cycles/min (with 1 cycle being maximum speed for 0.4 s and minimum speed for 0.6 s) was obtained by adding and subtracting 500 rpm to and from the rotational speed in nonpulsatile flow mode. Pulse pressures in the femoral artery and in the circuit just proximal to the perfusion cannula (6.5 mm Sarns high flow cannula with metal tip) were measured in 5 patients who underwent pulsatile cardiopulmonary bypass (CPB) for a coronary artery bypass graft (CABG), and compared to pulse pressures obtained by intraaortic balloon pumping (IABP) in 3 patients and by the pulsatile mode of the 3M Delphin pump in 3 patients. The platelet count, free hemoglobin, and β‐thromboglobulin (β‐TG) were measured and compared with measurements from another 5 patients who underwent nonpulsatile CPB. Although the pulse pressure measured in the circuit was 180 mm Hg on average, the pressure in the femoral artery was only 15 to 40 mm Hg with a mean of 20 mm Hg. In the same patients, 60 to 80 mm Hg pulse pressure was obtained with IABP. The pulse pressure obtained with the Delphin pump was not more than that obtained with the Terumo pump. There were no significant differences in percents of preoperative levels of platelet counts (pulsatile, 87.6 ± 15.8% and nonpulsatile, 72.4 ± 40.6%), free hemoglobin (pulsatile, 18 ± 8 mg/dl and nonpulsatile, 25 ± 7 mg/dl), and β‐TG (pulsatile 298 ± 28 ng/ml and nonpulsatile, 312 ± 143 nglml). In conclusion, although the pulsatile mode of the Terumo centrifugal pump did not exhibit any adverse effects hematologically, the pulse pressure obtained was unsatisfactorily small, mainly because of dumping caused by the perfusion cannula.
Prevention of Remote Organ Injury in Cardiopulmonary Bypass: The Impact of Flow Generation Technique
Authors: Hyde Jonathan A.J. , Riddington David W. , Hutton Peter , Wilson Ian C. , Boivin Christopher M. , Nash Gerard , Graham Timothy R.
Published: November 2008

Abstract: The purpose of this study was to investigate the effects of 3 different types of flow generation for cardiopulmonary bypass on gastrointestinal permeability and on neutrophil expression of CD11b, a surface marker of neutrophil activation. Fourteen patients undergoing elective coronary revascularization were selected randomly to receive 1 of the 3 flow generation techniques (roller, pulsatile, or centrifugal). Intestinal permeability was assessed by the fraction of an oral dose of 51chromium‐ethylenedi‐aminetetraacetate (51Cr‐EDTA) recovered in the urine over 24 h. Neutrophil activation was determined by expression of CD11b markers at 6 time points. Overall, the 14 patients showed significant increases in intestinal permeability. It was not possible to demonstrate statistically significant differences among the flow generation groups: however, when compared to both roller pump groups, the centrifugal pump group showed a 3.2% reduction in intestinal permeability. There was no change in the expression of CD11b receptors throughout the time points, nor was there a relationship of CD11b markers to the flow generation technique.
Removal of Plasmodium falciparum–infected red blood cells from whole blood by leukoreduction filters
Authors: Cardo Lisa J. , Salata Jeanne , Wilder Donna
Published: November 2008

BACKGROUND: There has been an unexplained decrease in the incidence of transfusion‐transmitted malaria in recent years. The decrease in incidence has paralleled the increasing use of leukoreduction filters. Malaria‐infected red blood cells (RBCs) share surface characteristics of hemoglobin S–containing cells. Because units collected from donors with sickle trait do not filter optimally due to adherence of RBCs to the filters, the possibility that malaria‐infected RBCs may also adhere to filters was investigated.

STUDY DESIGN AND METHODS: Malaria‐infected whole blood or calcium ionophore (A25187)‐treated and control RBCs were filtered with leukoreduction filters. Quantitation of malaria‐infected RBCs before and after filtration was performed by flow cytometry to determine the presence of DNA within RBCs, indicating malaria infection. Annexin V binding was also determined before and after filtration of RBCs treated with A25187. Immediately after filtration, filters were fixed and examined by scanning and transmission electron microscopy.

RESULTS: There were at least three configurations of adherence of malaria‐infected RBCs demonstrated within the filters. The first was direct adherence of infected RBCs to filter fibers; the second involved adherence of malaria‐infected RBCs to platelets, which were adherent to filter fibers; and the third was adherence of infected RBCs to other RBCs. Filtration also resulted in preferential removal of phosphatidylserine (PS)‐expressing cells as seen by the reduction of annexin V binding after filtration. This was further confirmed by electron micrographic examination of the filters in which untreated RBCs sit within the filter resting on top of filter fibers; however, calcium ionophore–treated RBCs are seen to cling tightly to the fibers.

CONCLUSIONS: PS expression by RBCs leads to their adherence within leukoreduction filters. Malaria‐infected RBCs are retained via more than one mechanism. The efficiency of removal requires further study.
Stylet penetration behavior of Myzus persicae related to transmission of Zucchini yellow mosaic virus
Authors: Symmes E. J. , Walker G. P. , Perring T. M.
Published: November 2008

The direct current electrical penetration graph (DC‐EPG) technique was used to identify stylet penetration behaviors of Myzus persicae (Sulzer) (Hemiptera: Sternorrhyncha: Aphididae) that are related to successful acquisition and inoculation of the non‐persistently transmitted potyvirus, Zucchini yellow mosaic virus (ZYMV), to melon, Cucurbita pepo L. (Cucurbitaceae). Stylet penetration behaviors of two sources of M. persicae that differ in their ZYMV transmission efficiency were examined to determine if behavioral differences were related to their differing ZYMV transmission efficiencies. Successful acquisition of ZYMV by M. persicae was significantly related to longer total time in intracellular subphase II‐3 of potential drops. Successful inoculation of ZYMV by M. persicae was related to a greater number of intracellular punctures, shorter durations of intracellular punctures, and longer total time in intracellular subphase II‐1. Of these variables that were related to ZYMV transmission, the two aphid sources differed in the total time spent in subphases II‐1 and II‐3. These results suggest that the differences in ZYMV transmission efficiencies between the aphids may be at least partially caused by behavioral differences during stylet penetrations of the host plant tissue, specifically behaviors that occur during intracellular punctures.
Starvation tolerance of macropter brown planthopper, Nilaparvata lugens, from temperate, subtropical, and tropical populations in East and South‐East Asia
Authors: Wada Takashi , Ito Kiyomitsu , Takahashi Akihiko , Tang Jian
Published: November 2008

We compared the starvation tolerance of macropter brown planthopper, Nilaparvata lugens Stål (Homoptera: Delphacidae), a characteristic favoring long‐distance migration, among populations collected from subtropical and temperate East Asia, tropical Indochina, and the Malay Peninsula. Starvation tolerance of planthoppers was significantly affected by climatic zone in which the planthoppers had been collected and by feeding duration after adult eclosion. After 24 h feeding on rice, newly emerged macropters originating from East Asia lived longer without feeding (starvation tolerance) than macropters from the tropical populations. The difference in longevity between the two groups of populations became more conspicuous when macropters fed on rice for 48 or 72 h, indicating that post‐eclosion feeding markedly increased starvation tolerance in East Asian populations relative to the tropical populations. These facts provide evidence that N. lugens populations that are adapted for long‐distance migration are distributed in subtropical and temperate East Asia. From the data on post‐eclosion feeding together with starvation tolerance, we discuss the timing of planthopper takeoff from paddies and the difference in resource allocation (vitellogenesis or stored resources) between East Asian and tropical populations.
Using survival regression to study patterns of expansion of invasive species: will the common waxbill expand with global warming?
Authors: Reino Luís , Moya‐Laraño Jordi , Cláudio Heitor António
Published: November 2008

Different approaches can be used to model the spread of invasive species. Here we demonstrate the use of survival regression, an approach that can be used to study a variety of events, not just death, to model the time to colonization. The advantage of survival regression to study colonisation of new areas is that information on those areas that have not been invaded by the end of a study can be included in the analysis, thus potentially increasing the accuracy of parameter estimation. We use proportional hazards regression (PHR; a type of survival regression) to model the spread of the common waxbillEstrilda astrildin Portugal. The species invaded Portugal in two peaks of invasion between 1964 and 1999. We built a PHR model with the information available up to the first invasion peak, then used this model to predict the pattern of invasion in the second peak. PHR had useful forecasting capabilities: areas that were actually colonised by 1999 had significantly higher hazards of colonization based on information from the first wave of invasion than areas that were not colonised. We then built a final model of expansion of the common waxbill that combined all available data up to 1999. Among climate variables, the most important predictor of colonization was temperature, followed by relative humidity. We used this model to estimate the invasion potential of the species under climate change scenarios, observing that an increase of 1°C in mean annual temperature increased the risk of a new invasion by 47%. Our analyses suggest that survival regression may be a useful tool for studying the geographical spread of invasive species. However, PHR was conceived as a descriptive technique rather than as a predictive tool, and thus further research is needed to empirically test the predictive capabilities of PHR.
Predicting the spread of an invasive plant: combining experiments and ecological niche model
Authors: Ebeling Susan K. , Welk Erik , Auge Harald , Bruelheide Helge
Published: November 2008

Rapid evolutionary adjustments to novel environments may contribute to the successful spread of invasive species, and can lead to niche shifts making range dynamics unpredictable. These effects might be intensified by artificial selection in the course of breeding efforts, since many successful plant invaders were deliberately introduced and cultivated as ornamentals. We hypothesized that the invasion success of Buddleja davidii, the ornamental butterfly bush, is facilitated by local adaptation to minimum temperatures and thus, exhibits unpredictable range dynamics. To assess the potential effects of adaptive evolution and artificial selection on the spread of B. davidii, we combined a common garden experiment investigating local adaptation to frost, with ecological niche modelling of the species’ native and invasive ranges. We expected that populations naturalized in sub‐continental climate are less susceptible to frost than populations from oceanic climate, and that the invasive range does not match predictions based on climatic data from the native range. Indeed, we revealed significant variation among invasive B. davidii populations in frost resistance. However, frost hardiness was not related to geographic location or climatic variables of the populations’ home site, suggesting that invasive B. davidii populations are not locally adapted to minimum temperatures. This is in line with results of our ecological niche model that did not detect a niche shift between the species’ native range in China, and its invasive range in Europe and North America. Furthermore, our niche model showed that the potential invasive range of B. davidii is still not completely occupied. Together with the frost resistance data obtained in our experiment, the results indicate that climatic conditions are currently not limiting the further spread of the species in Europe and North America.
The efficacy of oral irrigation in addition to a toothbrush on plaque and the clinical parameters of periodontal inflammation: a systematic review
Authors: Husseini A , Slot DE , Van der Weijden GA
Published: November 2008

Abstract:  Aim:  The aim of this review was to systematically review the literature on the adjunctive effect of oral irrigation in addition to toothbrushing on plaque and clinical parameters of periodontal inflammation.

Material and Methods:  Papers in the MEDLINE‐PubMed and Cochrane Central register of Controlled Trials (CENTRAL) databases up to January 2008 were searched to identify appropriate studies. Clinical parameters of periodontal inflammation such as plaque, bleeding, gingivitis and pocket depth, were selected as outcome variables.

Results:  Independent screening of the titles and abstracts of 809 PubMed and 105 Cochrane papers resulted in seven publications that met the eligibility criteria. Mean values and standard deviations were collected by data extraction. Descriptive comparisons with brushing alone or regular oral hygiene are presented.

Conclusion:  As an adjunct to brushing, the oral irrigator does not have a beneficial effect in reducing visible plaque. However, there is a positive trend in favour of oral irrigation improving gingivial health over regular oral hygiene or toothbrushing only.
Riboflavin‐induced Priming for Pathogen Defense in Arabidopsis thaliana
Authors: Zhang Shujian , Yang Xue , Sun Maowu , Sun Feng , Deng Sheng , Dong Hansong
Published: November 2008

Riboflavin (vitamin B2) participates in a variety of redox processes that affect plant defense responses. Previously we have shown that riboflavin induces pathogen resistance in the absence of hypersensitive cell death (HCD) in plants. Herein, we report that riboflavin induces priming of defense responses in Arabidopsis thaliana toward infection by virulent Pseudomonas syringae pv. tomato DC3000 (Pst). Induced resistance was mechanistically connected with the expression of defense response genes and cellular defense events, including H2O2 burst, HCD, and callose deposition in the plant. Riboflavin treatment and inoculation of plants with Pst were neither active but both synergized to induce defense responses. The priming process needed NPR1 (essential regulator of systemic acquired resistance) and maintenance of H2O2 burst but was independent of salicylic acid, jasmonic acid, ethylene, and abscisic acid. Our results suggest that the role of riboflavin in priming defenses is subject to a signaling process distinct from the known pathways of hormone signal transduction.
Involvement of Polyamine Oxidase in Abscisic Acid‐induced Cytosolic Antioxidant Defense in Leaves of Maize
Authors: Xue Beibei , Zhang Aying , Jiang Mingyi
Published: November 2008

Using pharmacological and biochemical approaches, the role of maize polyamine oxidase (MPAO) in abscisic acid (ABA)‐induced antioxidant defense in leaves of maize (Zea mays L.) plants was investigated. Exogenous ABA treatment enhanced the expression of the MPAO gene and the activities of apoplastic MPAO. Pretreatment with two different inhibitors for apoplastic MPAO partly reduced hydrogen peroxide (H2O2) accumulation induced by ABA and blocked the ABA‐induced expression of the antioxidant genes superoxide dismutase 4 and cytosolic ascorbate peroxidase and the activities of the cytosolic antioxidant enzymes. Treatment with spermidine, the optimum substrate of MPAO, also induced the expression and the activities of the antioxidant enzymes, and the upregulation of the antioxidant enzymes was prevented by two inhibitors of MPAO and two scavengers of H2O2. These results suggest that MPAO contributes to ABA‐induced cytosolic antioxidant defense through H2O2, a Spd catabolic product.
Construction of a Bacterial Artificial Chromosome Library of TM‐1, a Standard Line for Genetics and Genomics in Upland Cotton
Authors: Hu Yan , Guo Wang‐Zhen , Zhang Tian‐Zhen
Published: November 2008

A bacterial artificial chromosome (BAC) library was constructed for Gossypium hirsutum acc. TM‐1, a genetic and genomic standard line for Upland cotton. The library consists of 147 456 clones with an average insert size of 122.8 kb ranging from 97 to 240 kb. About 96.0% of the clones have inserts over 100 kb. Therefore, this library represents theoretically 7.4 haploid genome equivalents based on an AD genome size of 2 425 Mb. Clones were stored in 384 384−
well plates and arrayed into multiplex pools for rapid and reliable library screening. BAC screening was carried out by four‐round polymerase chain reactions using 23 simple sequence repeats (SSR) markers, three sequence‐related amplified polymorphism markers and one pair of primers for a gene associated with fiber development to test the quality of the library. Correspondingly, in total 92 positive BAC clones were identified with an average four positive clones per SSR marker, ranging from one to eight hits. Additionally, since these SSR markers have been localized to chromosome 12 (A12) and 26 (D12) according to the genetic map, these BAC clones are expected to serve as seeds for the physical mapping of these two homologous chromosomes, sequentially map‐based cloning of quantitative trait loci or genes associated with important agronomic traits.
The Turning Factor in the Estimation of Stream‐Aquifer Seepage
Authors: Morel‐Seytoux Hubert J.
Published: November 2008

A combined analytical‐numerical approach is presented to characterize properly the exchange flow between a stream and a hydraulically connected aquifer. It eliminates the need to use a three‐dimensional fine grid under and in the vicinity of the river cross section in order to obtain accurate results. Basically the approach matches an analytical solution in a vertical two‐dimensional (2D) plane with the numerical description of the aquifer behavior in a 2D horizontal plane. The approach is compared with a finite‐difference formulation such as used in MODFLOW.
Reconstruction of the Water Table from Self‐Potential Data: A Bayesian Approach
Authors: Jardani A. , Revil A. , Barrash W. , Crespy A. , Rizzo E. , Straface S. , Cardiff M. , Malama B. , Miller C. , Johnson T.
Published: November 2008

Ground water flow associated with pumping and injection tests generates self‐potential signals that can be measured at the ground surface and used to estimate the pattern of ground water flow at depth. We propose an inversion of the self‐potential signals that accounts for the heterogeneous nature of the aquifer and a relationship between the electrical resistivity and the streaming current coupling coefficient. We recast the inversion of the self‐potential data into a Bayesian framework. Synthetic tests are performed showing the advantage in using self‐potential signals in addition to in situ measurements of the potentiometric levels to reconstruct the shape of the water table. This methodology is applied to a new data set from a series of coordinated hydraulic tomography, self‐potential, and electrical resistivity tomography experiments performed at the Boise Hydrogeophysical Research Site, Idaho. In particular, we examine one of the dipole hydraulic tests and its reciprocal to show the sensitivity of the self‐potential signals to variations of the potentiometric levels under steady‐state conditions. However, because of the high pumping rate, the response was also influenced by the Reynolds number, especially near the pumping well for a given test. Ground water flow in the inertial laminar flow regime is responsible for nonlinearity that is not yet accounted for in self‐potential tomography. Numerical modeling addresses the sensitivity of the self‐potential response to this problem.
PRESIDENTIAL INFLUENCE AND CENTRALIZATION: THE CASE OF NIXON AND GEORGE ROMNEY
Authors: Lamb Charles M. , Twombly Jim
Published: November 2008

Political scientists have always been interested in presidential influence in American politics, but they have rarely explored the process of centralization as a mechanism for presidents to exert their influence. To date, Terry Moe has developed the best conceptual framework for understanding presidential influence in general and centralization in particular. We rely on and go beyond Moe's concept of centralization in a study of fair housing policy during the Nixon administration. Though we conclude that centralization may potentially be detrimental to existing democratic structures, there are cases where centralization may be the only viable alternative for a president to secure policy outputs in accordance with his desired outcomes.
Communitarian Citizenship and Civil Disobedience
Authors: Pickett Brent L.
Published: November 2008

Perhaps the most frequent criticism of communitarianism is that it is too sympathetic to community, and too hostile to individualism. It is alleged that the community and its agent, the state, are given too much power, and hence the important role of dissent is dangerously marginalized. To evaluate and respond to this criticism, this paper expounds the communitarian understanding of citizenship and addresses communitarians' critics, in part through a close reading of Charles Taylor's essay, “Atomism”. Some forms of communitarianism, especially those that put an emphasis upon citizen participation, have an adequate response to the critics. Moreover, in some ways communitarianism has a better understanding of, and a more central role for, dissent and civil disobedience.
Political Skills and Context in Prime Ministerial Leadership in Britain
Authors: Theakston Kevin
Published: November 2008

This article discusses the experience of the four prime ministers who have held office in Britain since 1976 (James Callaghan, Margaret Thatcher, John Major and Tony Blair) in order to explore the scope for, forms of and constraints upon prime ministerial leadership. The focus is on four key factors: party leadership, ideology and aims, political style and skills, and political and economic context. A favorable match of skill and context is crucial in determining the effectiveness of prime ministerial leadership. High‐level skill(s) deployed in a favorable situation make major achievements possible; accomplished statecraft and political astuteness in an unfavorable context may account for the difference between political survival and disaster; political misjudgments, a lack or loss of feel for the situation, or ineptness can aggravate problems and make a difference for the worse. Though structural, institutional and contextual factors are important, individual prime ministers' personalities, political skills and leadership styles are key and relevant variables.
Comparing Jacques Delors and Jacques Santer as Presidents of the European Commission: Skill in Supranational Context
Authors: Lord Christopher J.
Published: November 2008

This article compares the leadership skills that Jacques Delors (1985–1995) and Jacques Santer (1995–1999) brought to the presidency of the European Commission. It analyses challenges common to all presidents of the Commission, not least a wide range of disagreement as to exactly what their leadership role should be. It then goes on to qualify the received wisdom that Delors and Santer were ‘strong’ and ‘weak’ presidents respectively. Instead it suggests that the two men had contrasting leadership skills—those of risk‐taker (Delors) and consolidator (Santer)—which, crucially for the development of the European Union in the 1980s and 1990s, were deployed sequentially.
The Asymmetric Impact of Inflation on Presidential Approval
Authors: Cho Sungdai , Young Garry
Published: November 2008

This article examines the impact of unexpected inflation on U.S. presidential approval levels for the period 1953–96. Unlike most previous considerations of economic expectations and presidential approval, we find clear evidence that unexpected inflation affects approval, but it does so in an asymmetric fashion. Higher than expected inflation has a negative impact on presidential approval, and VAR results indicate that the effects linger for more than two years. In contrast, lower than expected inflation has a negligible impact on presidential approval.
Right to Privacy in the Federal District Courts: A Research Note
Authors: Stidham Ronald , Carp Robert A.
Published: November 2008

This study analyzes opinions published in the Federal Supplement between 1984 and 1995 which involve a right to privacy issue. Overall, only a slight majority of the opinions are supportive of the right to privacy claim raised in the case. However, opinions written by a Democratic judge are significantly more likely to support a right to privacy claim.