bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrafiltration by Hemofilter - A new Therapeutic Measure in Intractable Ascites
Authors: Lai K.N. , Leung J.W.C. , Loke J. , Panesar N.S. , Swaminathan R. , Vallance-Owen J. 
Published: April 2018

The clinical efficacy of ultrafiltration (UF) of ascitic fluid with hemofilter in the treatment of intractable ascites associated with chronic liver disease or intraabdominal malignancy was studied in fifteen patients. The ascitic fluid was reinfused into the peritoneal cavity after ultrafiltration. An average of 6.2 liters of fluid was removed during 4.4 hours of ultrafiltration with no significant change in blood pressure, central venous pressure, hemoglobin, platelets or plasma creatinine. Ascitic fluid albumin rose significantly immediately after the procedure (from 5.2 ± 4.3 gm/L to 31.9 ± 30.0 gm/L, P < 0.01). The plasma albumin concentration increased significantly at the end of UF (P < 0.001). Also there was a significant increase in urine output (P < 0.001), urinary sodium excretion (P < 0.001), and endogenous creatinine clearance (P < 0.01) during the 48 hours following UF. There was no evidence of hemodynamic, renal or hematological dysfunction, and other complications, including encephalopathy, peritonitis and variceal bleeding were not experienced. Ultrafiltration of ascitic fluid with hemofilter may be safely used in the temporary relief of refractory ascites due to cirrhosis or intra-abdominal malignancy.
Old Patients and Uremia: Rates of Acceptance to and Withdrawal from Dialysis
Authors: Husebye D.G. , Kjellstrand C.M. 
Published: April 2018

We studied the entry of elderly uremic patients to chronic dialysis in the U.S. in 1979. We also reviewed long-term survival, causes of death, and risk factors for death in old patients on dialysis at one center for the period 1966 to 1983. A comparison of the number of patients at risk with the number entering dialysis in the United States in 1979 indicates that 80% of the patients aged 25-45 years, 30% of patients over the age of 65 years, and 6% of those over the age of 75 years entered dialysis during that period. Of 239 patients over the age of 70 years followed at the Regional Kidney Disease Program at Hennepin County Medical Center in Minneapolis, the seven-year cumulative survival was 17%. In this program withdrawal from dialysis was the commonest cause of death, accounting for 40% of all deaths. Age groups over 75 years, sex, time period, duration of dialysis, eight pre-existing degenerative diseases, living situation, family support, and site and type of dialysis were not risk factors for termination of dialysis, but living in a nursing home was. When compared to the young, total deaths and deaths from discontinuation were much higher, and this decision was made earlier. Half of the patients who died because dialysis was discontinued were competent and decided for themselves; the other half were incompetent and families and physicians made the decision. Thus, old patients do not live as long, and they withdraw from dialysis more frequently than the young. Qualitatively, though, the decisions to stop dialysis are no different from those decisions made by or for younger patients.
Solute and Water Transport during Continuous Arteriovenous Hemofiltration (CAVH)
Authors: Ronco C. , Brendolan A. , Bragantini L. , Fabris A. , Feriani M. , Chiaramonte S. , Dell'aquila R. , Milan M. , La Greca G. 
Published: April 2018

The transport mechanisms governing solvent and solute removal during CAVH were elucidated on the basis of in vitro and in vivo observations. Using a typical hemofilter (Diafilter D-20, AMICON), filtration rate rose with inlet blood flow rate until an asymptote was reached at blood flows of approximately 150 ml/min. The onset of the asymptote coincided with transition from a regime controlled by oncotic pressure (filtration pressure equilibrium), to one governed by simple Darcy's law filtration behaviour. Subsequent measurements showed that under clinical conditions, CAVH is generally in the pre-asymptotic regime and operates at filtration pressure equilibrium. These observations offer the theoretical bases for a new design for CAVH hemofilters. As a possible corollary, middle-molecule sieving coefficients were found to be stable with time during CAVH in vivo, whereas in chronic mechanical hemofiltration they declined significantly during clinical treatment. The sieving coefficients, however, were lower in mechanical hemofiltration from the beginning of the session. These observations suggest that the measured sieving coefficient for a membrane is not necessarily a constant directly and solely related to the membrane standard reflection coefficient for a given solute. Concentration polarization and the ultrafiltration rate per unit of surface area may in fact have a major effect on the final concentration of solutes in the ultrafiltrate.
Effects of Membrane Plasma Exchange on the Hemostatic System and on Thyroid Hormones in Critically Ill Patients
Authors: Krämer B.K. , Ickrath O. , Keppler G. , Ress K.M. , Risler T. 
Published: April 2018

The present study examined the effects of repeated plasma exchanges with membrane filtration (Plasmaflux P2 membrane, 4.3 I human albumin solution) on the hemostatic system and on thyroid hormones in critically ill patients. Clotting factors V, VII, VIII, IX, X, XI, XII, XIII, fibrinogen, antithrombin III (ATIII), prothrombin time (PT), activated partial thromboplastin time (PTT), total (TT3) and free tri-iodothyronine (FT3), total (TT4) and free thyroxine (FT4), and thyroxine binding globulin (TBG) were determined before, immediately after, 1, 3, 6 and 24 h after plasma exchange in 6 patients (3 with glomerulonephritis, 2 with IgG myeloma, 1 with chronic polyneuritis) during 18 plasma exchanges. After plasma exchange levels of clotting factors and ATIII were markedly lowered but except for fibrinogen and factor XIII, they were not reduced by repeated exchange procedures. Thyroid hormones and TBG were reconstituted after 24 h. Pre-exchange levels, except for TT4 and TBG, were not lowered by repeated exchange procedures. Risk of bleeding or thrombosis is small and there is no appreciable risk of loss of thyroid hormones during repeated plasma exchanges.
Clinical Evaluation of a New High-Flux Cellulose Acetate Membrane
Authors: Schaefer R. M. , Huber L. , Gilge U. , Bausewein K. , Vienken J. , Heidland A. 
Published: April 2018

One major goal of dialysis therapy has become the removal of ß2-microglobulin (ß2-m). The interdialytic elimination of ß2-m was studied using a newly developed high-flux cellulose acetate (CA) membrane. The results show that high-flux CA dialyzers offer better biocompatibility than classical Cuprophan or high-flux Cuprophan devices, with regard to leukopenia, C3a desarg generation, and elastase release from polymorphonuclear (PMN) leukocytes. Compared to high-flux CA membranes, high-flux PMMA membranes induce less C3a desarg formation but comparable leukopenia. High-flux PMMA membranes, however cause greater leukocyte stimulation than CA as demonstrated by more PMN elastase release during hemodialysis. Using high-flux CA or high-flux PMMA membranes, serum ß2-m levels decreased 32% during dialysis. Serum ß2-m dropped 10% with high-flux Cuprophan membranes, but remained unchanged with conventional Cuprophan dialyzers. Sieving coefficients for ß2-microglobulin (ß2-m) were virtually zero with classical Cuprophan and 0.66 with high-flux cellulose acetate membranes. High-flux membranes made of Cuprophan and PMMA gave coefficients of 0.25 and 0.45, respectively. This indicates the high removal capacity of the new CA-membrane for substances with high molecular weight. This high-flux CA membrane thus appears to combine a good degree of biocompatibility with a high capacity for ß2-m removal.
Isolation of Unusually Composed Sialyl-Compounds from Hemofiltrate
Authors: Brunner H. , Weißhaar G. , Friebolin H. , Baumann W. , Mann H. , Sieberth H.G. , Opferkuch H.J. 
Published: April 2018

Sialyl compounds are essential components of various biological fluids but relatively little is known about their occurrence in the extracellular fluid of patients with end-stage renal disease. As we have developed a macropreparative method for concentrating and desalting a wide range of fractions from diluted biological fluids we have been able to isolate and identify 5 sialooligosaccharides, 3 sialosugarphosphates, 2 monosialoglycopeptides and 1 disialoglycopeptide. The structures have been elucidated predominantly by one and two-dimensional NMR spectroscopy, enzymatic degradation and FAB mass spectrometry. The accumulation of these compounds in uremic sera may be of particular interest as they may interact in the molecular biology of diseases typically associated with the uremic state, e.g., immune deficiency, neurological disorders, receptor binding abnormalities, complement system disturbances and cell membrane alterations.
Effects of Oral Base Therapy on Serum Ionized Calcium, Phosphorus and Parathyroid Hormone in Chronic Hemodialysis Patients
Authors: Caruana R. J. , Weinstein R. S. , Campbell H. T. , Chaudhary B. A. , Smith K. L. , Kurunsaari K. M. 
Published: April 2018

The purpose of this study was to evaluate the effects of oral base therapy on selected chemical parameters in chronic hemodialysis patients. Oral base supplements were administered to 20 acidotic chronic hemodialysis patients for one month. Serum bicarbonate levels rose from 18.6 ± 2.9 to 22.5 ± 4.0 mEq/L (p<0.0005) and pH rose from 7.35 ± 0.03 to 7.39 ± 0.04 (p<0.0005). Serum ionized calcium levels fell from 5.03 ± 0.37 to 4.83 ± 0.34 mg/dL (1.25 ± 0.09 to 1.21 ± 0.08 mmol/L) (p<0.01), while intact parathyroid hormone (PTH) levels rose from 547 ± 697 to 619 ± 776 pg/mL (p<0.05). Base therapy did not result in significant changes in serum levels of total calcium, phosphorus, alkaline phosphatase, urea nitrogen, creatinine, total protein, albumin or potassium. If empiric therapy with exogenous base is given to dialysis patients, ionized calcium levels should be closely monitored since changes in calcium supplement or vitamin D therapy may be required to maintain ionized calcium and parathyroid hormone values at the pre-treatment levels.
Use of Hepatocytes in Adhesion and Suspension Cultures for Liver Support Bioreactors
Authors: Gerlach J. , Klöppel K. , Schauwecker H.H. , Tauber R. , Müller Ch. , Bücherl E.S. 
Published: April 2018

Hepatocyte cultivation in bioreactors for hybrid liver support systems is possible under two conditions: attached to a substrate like membranes or microcarriers or in suspension culture. To compare the ammonia metabolism of hepatocytes cultivated under these two conditions, cultures of primary seeded rat hepatocytes were cultivated either attached to collagen coated tissue culture plastic or as a suspension culture. During the time course of culture, the ability of hepatocytes to reduce the ammonia content of the medium decreased in both adhesion and suspension cultures, though to different extents. In suspension cultures, ammonia content was reduced from 350 μM to about 100 μM (day 4) and to about 180 μM (day 6). No significant reduction was seen on day 8 of culture. In contrast, hepatocytes attached to collagen coated dishes remained viable and functional for at least 8 days after plating, reducing ammonia content from 350 μM to 70 μM (day 4), 90 μM (day 6) and 180 μM (day 8). The period of useful metabolism of hepatocytes in bioreactors for hybrid liver support systems appears to depend on the culture conditions
Prevention of Chronic Glomerular Uremia in Steroid Resistant Glomerulonephritis. A Clinical Trial with a New Antithrombotic Agent
Authors: Frascà G.M. , Vangelista A. , Martella D. , Dondi M. , Bonomini V. 
Published: April 2018

To investigate the possibility of slowing down disease progression 27 patients with primary glomerular diseases unresponsive to steroids and cytotoxic drugs were treated with Defibrotide. This drug is a single stranded DNA fraction which has profibrinolytic and deaggregating properties and can promote the generation and release of prostacyclin from vascular tissue. Before treatment all patients showed proteinuria in excess of 1 g/day and 16 had a nephrotic syndrome (59%); 10 patients had serum creatinine above 1.6 mg/dl (37%) and 6 were hypertensive. After therapy a significant decrease in daily proteinuria was observed, although the reduction exceeded 50% of pre-treatment values in only 16 patients (59%). A progressive decrease in serum creatinine occurred in patients with abnormal renal function; serial measurement of renal plasma flow showed a progressive improvement with an average increase of 6 and 12%, after 1 and 3 months of treatment, respectively. These observations confirm the view that drugs improving endothelial function and renal hemodynamics can be of value in the treatment of chronic glomerular diseases and can contribute to the maintenance of renal function.
Effect of Left Ventricular Assistance on Sympathetic Tone
Authors: Yambe T. , Nitta S. , Katahira Y. , Sonobe T. , Tanaka M. , Miura M. , Satoh N. , Mohri H. , Yoshizawa M. , Takeda H. 
Published: April 2018

To determine the effect of left ventricular assist device (LVAD) pumping on sympathetic tone, renal sympathetic nerve activity (RSNA) was detected in acute animal experiments. Our TH-7B pneumatically driven, sac-type ventricular assist device was used in 7 adult mongrel dogs. RSNA was detected by the use of bipolar electrodes attached to the left renal sympathetic nerve. RSNA was amplified and integrated by use of an R-C integrator circuit. The area of the integrated nerve discharge per unit time was calculated in the computer system and expressed as RSNA per unit time. During LVAD pumping, RSNA decreased with increase in blood pressure, with an increase in pulmonary artery flow, and with a decrease in left atrial pressure. These data suggest that LVAD has an effect on the sympathetic nervous system which is mediated by the aortic and cardiopulmonary baroreflex system.
Automatic Modules for Extracorporeal Circulation Control
Authors: Chauveau N. , Van Meurs W. , Barthelemy R. , Morucci J.P. 
Published: April 2018

Maintenance of a constant level in the oxygenator during surgical extracorporeal circulation (ECC) is of paramount importance. We propose a device able to regulate the pump speed accordingly to the level in the oxygenator, and an automatic clamp to control venous return from the patient. The level regulator permits pump speed control and also stops the pump when a prefixed low level is reached (during ECC). Linearization of the level sensor has been made in order to optimize the PI regulator. Simulation results are presented and the regulator is evaluated in a clinical environment. The automatic clamp provides a good solution for reproducible and easy transitions in venous return. When coupled with the level regulator, the pump speed will increase automatically from zero to the correct equilibrium speed, with variable duration (from 30 seconds to 5 minutes) chosen by the operator. The same technique is used for stopping the ECC. These two devices are, in fact, modules, making up part of an evolutive device for ECC automation. The modules can exchange data with a supervising microcomputer.
Biocompatibility of Blood Tubings
Authors: Branger B. , Garreau M. , Baudin G. , Gris J.C. 
Published: April 2018

We studied hemocompatibility of various blood tubings with C3a anaphylatoxin measurement and comparative electron scanning microscopy. The following tubing materials were tested: polyvinylchloride (PVC) plasticised with phthalate (PVC), pvc plasticised with phthalate coextruded with polyurethane (PIV), and two phathalate-free lines: pvc plasticised with trimellitate coextruded with polyurethane (TRI) and pvc plasticised with LT 360 (LTP). Results of C3a generation rate showed a significant activation by all blood tubings, with a reduced rate with PIV when compared to all others. Electron scanning microscopy showed marked alterations of PIV surface on tubings stored for 6 months. Protein deposits on internal surfaces after dialysis were similar whatever tubing material was tested, but adhesive cell number was greater with TRI when compared to PVC and LTP. Hemocompatibility is unchanged with phthalate-free tubings when compared to phthalate plasticised ones. In contrast with phthalate plasticised PVC there is no beneficial effect of polyurethane coextrusion with trimellitate plasticised PVC in regard to C3a generation.
New Methods for the Development of Pneumatic Displacement Pumps for Cardiac Assist
Authors: Knierbein B. , Rosarius N. , Reul H. , Rau G. 
Published: April 2018

The primary goal of the presented project was to develop a pump family with stroke volumes of 20, 50, 70 and 90 ml, which could be produced at low cost but with sufficient quality. The housing parts of the pump were thermoformed from technical semifinished materials. All blood contacting surfaces of the pump were coated with biomaterials in a controlled dipping process. During the design and fabrication process a professional CAD-system was used. This facilitated spatial presentations of pump components for first evaluations at the initial draft stages. The CAD-design data were then transformed to CNC-controlled lathes and mill's for the fabrication of pump tools. The stresses and strains of the moving blood pump components, such as membranes and valves, were precalculated by means of Finite-Element-Analysis (FEM). After completion of the pump, the internal flow fields were investigated by flow-visualization techniques using non-Newtonian test fluids, and the pump characteristics (function curves) were investigated in appropriate circulatory mock loops. The paper covers all above aspects from first draft to final fabrication and testing.
Plasma-exchange in Chronic Peripheral Neurological Disorders
Authors: Mazzi G. , Raineri A. , Zucco M. , Passadore P. , Pomes A. , Orazi B.M. 
Published: April 2018

We investigated 19 patients affected by chronic peripheral neurological disorders treated with therapeutic plasma exchange (TPE) to verify the efficacy of the therapeutic protocol used in these diseases. Every patient was clinically considered after 5 TPE. Those who showed an improvement started chemotherapy and continued TPE at the rate of 2 procedures/week for 2 weeks, then 1 procedure/week for 1 month and finally 1 procedure every 2 weeks for 2 months. Intravenous immunoglobulins (IVIg) were infused at the end of apheretic treatment in one of the patients affected by neurological disorders due to monoclonal gammopathy undetermined significance. HCV-positive patients with cryoglobulins were treated with α-interferon (α-IFN) for 6 months before TPE. Eleven patients (58%) had a symptomatic improvement, 2 (1.5%) stopped TPE treatment owing to side effects and 6 (31.5%) did not respond to apheretic therapy. In order to improve the advantages of TPE we suggest using IVIg at the end of apheretic therapy, while in HCV-positive patients, at least one year of α-IFN therapy is required before initiating TPE.
The “Aachen” Keratoprosthesis: A New Approach towards Successful Keratoprosthesis-Surgery
Authors: von Fischern T. , Langefeld S. , Yuan L , VÖlcker N. , Reim M. , Kirchhof B. , Schrage N. F. 
Published: April 2018

Background None of the keratoprostheses available today is absolutely successful in the long term, neither the problems of extrusion, retroprosthetic membrane formation and intraocular pressure rise are yet solved. A new type of keratoprosthesis is required which can show improved ingrowth characteristics and allow intraocular pressure measurements. In order to possibly meet the above mentioned requirements we developed a flexible silicone keratoprosthesis with scleral fixation and chemical surface modification. Methods The one-piece keratoprosthesis is made of silicone rubber. Its optical zone has a diameter of 11 mm and is 0.3 mm thick. The surface-modified haptic consists of a scleral rim and eight branches for scleral fixation. A ridge at the back of the keratoprosthesis fitting into the trephination hole shall avoid leakage and retroprosthetic membrane formation. Optical and mechanical qualities are characterised by tensile tests, spectrophotometry and topography. Results A method for keratoprosthesis-production was established. The optical quality of the device was improved by submicron lathing of the mould. Spectrophotometry showed high visible and ultraviolet light transmission of the silicone. Mechanical tests with silicone samples revealed high tensile strength and elongation at break. The mechanical properties were not impaired by surface modification. Conclusions The production of a flexible silicone keratoprosthesis with high optical and mechanical properties was established. Its use both for the treatment of permanently opacified corneas and as temporary keratoprosthesis seems to be possible.
Plantar Pressure Measurements and Geometric Analysis of Patients With and Without Morton’s Neuroma
Authors: Naraghi Reza , Slack-Smith Linda , Bryant Alan 
Published: April 2018

Background: The purpose of this research was to see if there were any differences in peak pressure, contact time, pressure-time integrals, and geometric variables such as forefoot width, foot length, coefficient of spreading, and arch index between subjects with Morton’s neuroma (MN) and control subjects. Methods: Dynamic peak plantar pressure, contact time, pressure-time integral, and geometric data were extracted using the EMED-X platform in 52 subjects with MN and 31 control subjects. Differences in peak pressure, contact time, pressure-time integral, and geometric data between participants with and those without MN were determined using independent-samples t tests. There were no significant differences in age, weight, height, and body mass index between patients with MN and control subjects. Results: There were no significant differences in the peak pressures of all masked areas and pressure-time integrals under metatarsal 2 to 4 heads between patients with MN and control subjects. In addition, no significant differences were observed between patients with MN and control subjects in geometric measurements of forefoot length, width, coefficient of spreading, foot progression angle, and arch index. Conclusion: No relationship was found in this study between peak pressure, contact time, and pressure-time integral under the metatarsal heads, forefoot width, foot length, coefficient of spreading, and foot progression angle in a symptomatic MN group compared with a control group. The need to perform osteotomies to treat MN not associated with other lesser metatarsal phalangeal joint pathologies is questionable. Level of Evidence: Level III, Case-Control Study