Abstract:
:Stimulation of different spinal cord segments in humans is a widely developed clinical practice for modification of pain, altered sensation, and movement. The human lumbar cord has become a target for modification of motor control by epidural and, more recently, by transcutaneous spinal cord stimulation. Posterior columns of the lumbar spinal cord represent a vertical system of axons and when activated can add other inputs to the motor control of the spinal cord than stimulated posterior roots. We used a detailed three-dimensional volume conductor model of the torso and the McIntyre-Richard-Grill axon model to calculate the thresholds of axons within the posterior columns in response to transcutaneous lumbar spinal cord stimulation. Superficially located large-diameter posterior column fibers with multiple collaterals have a threshold of 45.4 V, three times higher than posterior root fibers (14.1 V). With the stimulation strength needed to activate posterior column axons, posterior root fibers of large and small diameters as well as anterior root fibers are coactivated. The reported results inform on these threshold differences, when stimulation is applied to the posterior structures of the lumbar cord at intensities above the threshold of large-diameter posterior root fibers.
journal_name
Artif Organsjournal_title
Artificial organsauthors
Danner SM,Hofstoetter US,Ladenbauer J,Rattay F,Minassian Kdoi
10.1111/j.1525-1594.2011.01213.xsubject
Has Abstractpub_date
2011-03-01 00:00:00pages
257-62issue
3eissn
0160-564Xissn
1525-1594journal_volume
35pub_type
杂志文章abstract::The VentrAssist pump has no shaft or seal, and the device is unique in design because the rotor is suspended passively by hydrodynamic forces, and urging is accomplished by an integrated direct current motor rotor that also acts as the pump impeller. This device has led to many challenges in its fluidic design, namely...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2000.06584.x
更新日期:2000-06-01 00:00:00
abstract::The major restrictions to the transport of solute and solvent across the peritoneum are the limited peritoneal blood flow, area and permeability. Recent investigations have demonstrated that several vasoactive drugs influence transport parameters. Isoproterenol, nitroprusside, dipyridamole and dopamine exemplify drugs...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1979.tb01052.x
更新日期:1979-08-01 00:00:00
abstract::Thirteen percent of 99 patients undergoing maintenance hemodialysis showed an increased predialysis peripheral blood eosinophil count (mean value of 828 cells/mm3, range 410-2,710). Patients with eosinophilia were predominantly male and evidenced more frequent elevation of total plasma IgE levels. Otherwise, no differ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1987.tb02635.x
更新日期:1987-04-01 00:00:00
abstract::Right ventricular (RV) function immediately after left ventricular assist device (LVAD) implantation is a crucial prognostic factor. RV failure is linked to increased mortality and worse outcome. A phosphodiesterase 5 inhibitor, sildenafil, was shown to decrease pulmonary vascular resistance and pulmonary artery press...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12277
更新日期:2014-11-01 00:00:00
abstract::Characteristics of morphology, cardiac function, and cardiac reserve at late state were evaluated at rest, by changing the pacing rates, and after exercise in patients with ventricular pacemakers for isolated congenital complete atrioventricular block. Heart size was reduced statistically after pacemaker implantation,...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1987.tb02667.x
更新日期:1987-06-01 00:00:00
abstract::In a healthy human cardiac system, a large asymmetric clockwise vortex present in the left ventricle (LV) efficiently diverts the filling jet from the mitral annulus to the left ventricular outflow track. However, prior clinical studies have shown that artificial mitral valve replacement can affect the formation of ph...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13781
更新日期:2020-12-01 00:00:00
abstract::Sera from 138 patients who had experienced hypersensitivity-type reactions while on hemodialysis (reactors) were examined retrospectively by the radioallergosorbent test (RAST) for specific IgE antibody to ethylene oxide (ETO). Seventy-eight hemodialysis patients without a history of reaction were also evaluated as co...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1987.tb02638.x
更新日期:1987-04-01 00:00:00
abstract::The therapy of terminal heart failure with left ventricular assist devices has become a standard in cardiac surgery. Yet the surgical implantation technique is not standardized and differs from center to center. Complications associated with left ventricular assist device (LVAD) inflow cannula placement are thrombosis...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12735
更新日期:2017-03-01 00:00:00
abstract::Pump power loss is defined as input power that is not used for the output work of the pump. Less pump power loss means a higher pump efficiency. A common opinion is that the pump power loss is closely related to heat generation of the pump, which may affect not only the endurance of pump materials, but also blood dama...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1996.tb04542.x
更新日期:1996-07-01 00:00:00
abstract::Plasma levels of the platelet markers beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) are among the most sophisticated indexes of biocompatibility available to evaluate new members for hemodialysis. This investigation was designed to determine the extent of platelet activation by measuring the alpha-granule...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1987.tb00954.x
更新日期:1987-10-01 00:00:00
abstract::We assessed the relationship of certain clinical variables (including bradykinin [BK] release and dialysis membrane) to initial mean arterial pressure (MAP) reduction in 47 patients requiring continuous renal replacement therapy (CRRT) in an intensive care unit. The pretreatment MAP was 84 +/- 14 mm Hg for the group a...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2001.06703.x
更新日期:2001-12-01 00:00:00
abstract::As the aortic valve (AV) opens, the pump pressure head remains constant, which is reflected as a "notch/plateau" in pump pressure and flow signals. However, instantaneous flow estimation may be influenced by friction and is particularly difficult in axial pumps. Therefore, a new method to determine the duration of AV ...
journal_title:Artificial organs
pub_type: 杂志文章,多中心研究
doi:10.1111/aor.12570
更新日期:2015-08-01 00:00:00
abstract::Two series of experiments were conducted to assess the potential of artificial ventricular bypass in restoring cardiac activity. One series evaluated use of a paracorporeal left ventricle in 17 calves; the other evaluated biventricular bypass in 11 calves. Module pumps with a seamless blood chamber of polyurethane wer...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1987.tb02622.x
更新日期:1987-02-01 00:00:00
abstract::Polynitroxylated pegylated hemoglobin (PNPH) as a multifunctional therapeutic takes advantage of the ability of hemoglobin (Hb) to transport oxygen, the antioxidative stress activities from the redox coupling of nitroxide and heme iron, and the hypercolloid properties of pegylation. The published preclinical data demo...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2011.01307.x
更新日期:2012-02-01 00:00:00
abstract::One hundred and seventy-two patients at The Methodist Hospital in Houston, Texas, were placed on BioMedicus centrifugal ventricular support. One hundred thirty-nine patients were male and 33 were female with a mean age of 59.7 years. Reasons for support were postcardiotomy cardiac failure (129 patients), cardiac allog...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1995.tb02419.x
更新日期:1995-07-01 00:00:00
abstract::Biofilms are communities of bacteria that can cause infections which are resistant to the immune system and antimicrobial treatments, posing a significant threat for patients with implantable and indwelling medical devices. The purpose of our research was to determine if utilizing specific parameters for electric curr...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12678
更新日期:2016-08-01 00:00:00
abstract::The feasibility of extracorporeal adsorption of 1.5-3 L plasma on protein A-Sepharose was investigated in six patients with advanced cancer. Anticoagulation with heparin was associated with respiratory distress syndrome in two patients, most likely caused by complement activation as indicated by a transient leukopenia...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1984.tb04247.x
更新日期:1984-02-01 00:00:00
abstract::A physiological controller is a key component to optimize the performance of left ventricular assist devices (LVADs) from short term to long term (10-20 years). The difficulties of its design lie in the inaccurate modeling of any particular human cardiovascular system because of limited knowledge, the large fluctuatio...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2004.07381.x
更新日期:2004-10-01 00:00:00
abstract::Tissue responses to various percutaneous materials with different surface properties and structures were investigated. Dense hydroxyapatite (HA), tricalcium phosphate (TCP), glassy carbon (GC), and 2 types of porous HA were used. Cutaneous and subcutaneous tissues were tightly attached to the surface of the penetratin...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1997.tb00514.x
更新日期:1997-09-01 00:00:00
abstract::The abdominal left ventricular assist device (ALVAD) is an order of magnitude more effective than conventional intra-aortic balloon pumping (IABP) in unloading and providing circulatory support to the failing left ventricle. This is a report of a unique case which demonstrates that in the absence of pulmonary vascular...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1978.tb01632.x
更新日期:1978-11-01 00:00:00
abstract::While pediatric HeartWare HVAD application has increased, determining candidacy and timing for initiation of pediatric VAD support has remained a challenge. We present our experience with a systematic approach to HVAD implantation as a bridge to pediatric heart transplantation. We performed a retrospective, single cen...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13344
更新日期:2019-01-01 00:00:00
abstract::To overcome the weak mechanical properties of cell/hydrogel composites, a poly(DL-lactic-co-glycolic acid) sandwiched adipose-derived stem cell (ADSC)/fibrin construct was fabricated using a step-by-step mold/extraction method to generate the middle smooth muscle layer of natural blood vessels. A pulse bioreactor with...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2010.01137.x
更新日期:2011-06-01 00:00:00
abstract::In a preliminary experiment, 38% of the spent dialysis fluid water was reclaimed by a forward osmosis process through a cellulose triacetate membrane. The simplicity of forward osmosis and its minimal external energy requirements may allow the construction of a small bulk device that can reclaim a considerable portion...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2009.00816.x
更新日期:2009-12-01 00:00:00
abstract::To develop an effective hybrid bioartificial liver (BAL) device, the material of the scaffold is very important to support hepatocytes that have both growth ability and hepatic differentiated functions. In this study we used paper (Kimwipe, Kimberly-Clark Corp., Roswell, GA, U.S.A.) as a scaffold. Primary hepatocytes ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2000.06506.x
更新日期:2000-04-01 00:00:00
abstract::One hundred eighty-eight Mitroflow pericardial valves, implanted on 166 patients from March 1983 to December 1986, have been followed for a total of 4316 patients x months. Mortality rate in the first three postoperative months is approximately 10% related to noncardiac complications. One hundred forty-nine patients a...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1988.tb02781.x
更新日期:1988-08-01 00:00:00
abstract::Total hip arthroplasty (THA) can be achieved by using a cemented or noncemented prosthesis. Besides patient's age, weight, and other clinical signs, the evaluation of the quality of the bones is a crucial parameter on which orthopedic surgeons base the choice between cemented and noncemented THA. Although bone density...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12033
更新日期:2013-06-01 00:00:00
abstract::The presence in rat serum of three novel immunosuppressive proteins is associated with induction of tolerance after liver grafting. One of these, KX-5 (40 kilodalton molecular weight) is present 40-100 days after grafting of DA liver into PVG, a combination in which liver grafts are not rejected; two others, KX-2 (87 ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1996.tb00646.x
更新日期:1996-10-01 00:00:00
abstract::The major problems with existing centrifugal pumps are leakage, mechanical trauma, and thrombus formation. In consideration of these problems, a new compact centrifugal pump system was developed. The purpose of this study was to evaluate the new centrifugal pump system clinically. Ten patients underwent open heart sur...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1994.tb03403.x
更新日期:1994-09-01 00:00:00
abstract::Flow visualization experiments and computational fluid dynamic (CFD) analyses were performed and the results were compared to clarify the detailed fluid dynamic characteristics for the prototype design of a centrifugal pump, namely, an implantable ventricular assist system from Sun Medical, whose hemocompatibility was...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2004.07161.x
更新日期:2004-05-01 00:00:00
abstract::Loss of photoreceptor cells is one of the major causes of blindness. Several groups are exploring the functional replacement of photoreceptors by a retinal prosthesis. The goal of this study was to simulate the vision levels that recipients of retinal prostheses with 4 x 4, 6 x 10, and 16 x 16 electrode arrays may exp...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2003.07309.x
更新日期:2003-11-01 00:00:00