bluuebunny/crossref_metadata_2025 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.
Serum Ferroxidase I and II in Uremic Patients under Conservative Treatment and Maintenance Hemodialysis
Authors: Frangos-Plemenos M. , Agroyannis B. , Koutsicos D. , Tzanatos-Exarchou H. , Logothetis E. , Sarris E. , Kaya S. , Yatzidis H.
Published: April 2018

Serum ferroxidase I (ceruloplasmin) and ferroxidase II activities were studied in 49 uremic patients under conservative treatment, in 79 patients undergoing hemodialysis and in 56 healthy subjects, as controls. Ferroxidase I was significantly higher in both groups of patients. Ferroxidase II was significantly elevated only in patients undergoing chronic hemodialysis. The cause of this difference is not clear, but seems to be of considerable interest.
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.
Enrichment of Marrow Hemopoietic Progenitor Cells using a Blood Cell Processor
Authors: Angelini A. , lacone A. , Dragani A. , Accorsi P. , D'Antonio D. , Geraci L. , Berardi A. , Quaglietta A. , Cacciafiori G. , Mascitelli G. , Vizioli M. , Di Bartolomeo P. , Torlontano G.
Published: April 2018

A total of 93 bone marrows (BM) from normal donors and patients were processed using the IBM-COBE 2991 blood cell washer to produce a concentrated buffy coat (BC) for either bone marrow transplantation (BMT) or cryopreservation for subsequent autologous BMT. The reduction in volume was 73.3 ± 8.5% and nucleated blood cells (NBC) recovery was 87.1 ± 9.1% of original marrow. Red blood cell (RBC) and platelet (PLT) contamination was reduced 64.5 ± 10.9% and 41.2 ± 24.1%, respectively. Clonogenic activity indicated that the NBC fraction was highly enriched in hematopoietic progenitor cells (> 100%) as assessed in vitro (CFU-GM). Results were not affected by diagnosis, initial marrow volume or cell count of the BM suspension. We conclude that this is a simple and reproducible method using blood bank, facilities and permits BC preparation from BM without significant loss of hematopoietic progenitor cells.
Comparative Evaluation of Disk- and Tri Leaflet Valves in Left-Ventricular Assist Devices (LVAD)
Authors: Reul H. , Taguchi K. , Herold M. , Lo H.B. , Reck B. , MÜckter H. , Messmer B.J. , Rau G.
Published: April 2018

Two identical LVADs were equipped with different types of heart valve prostheses (Björk-Shiley disk and PU-valves) and tested in two simultaneous calf experiments for 28 days each. Noise levels, accelerations of the pump housing and thrombus formation were higher for the mechanical valve pump.
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.
Continuous Transcutaneous Gas Monitoring in Adults on Regular Dialysis Treatment
Authors: Agazia B. , Guarda L. , Lombini C. , Saporiti E.
Published: April 2018

We tested a transcutaneous (tc) oxygen (O2) and carbon dioxide (COz) sensor in 15 normal adults and in 20 patients on regular dialysis treatment (RDT). We compared the tc gas values (ptcO2, PtcCO2) with the gas tension values in arterial blood samples (PaO2, PaCO2), in normal adults and in RDT-patients at the end of a 30-min test and six times during RDT. During the test, PtcO2 correlated with PaO2 both in normal adults (r 0.72p<0.01) and in RDT patients (r 0.41 p<0.05). PtcCO2 correlated with PaCO2 (r 0.59 in normal adults and r 0.76 in RDT). During 14 acetate dialyses the changes were expressed as %Δ from time 0. %Δ PaO2 was – 12.7 at 60 min, + 4.8 at 240 min; %Δ PtcO2 – 6.0 at 60 min, + 9.7 at 240 min; %Δ PaCO2 – 17.7 at 240 min, – 1.8 1 h later; %Δ PtcCO2 was – 15.8 at 240 min, – 3.2 1 h later. Both in normal adults and in RDT, patients there was a good relationship between PtcCO2 and PaCO2 values. In normal adults the absolute PtcO2 values were always lower than PaO2 (– 14.4± 10 mmHg); in RDT-patients this difference was more pronounced (– 27.6± 15.1) and is probably attributable to the lower Hb levels (6.7± 1.1 vs 12.4± 1.2). During RDT the pattern was the same between tc and gas tension values. The tc-sensor seems to be useful in continuous monitoring, especially in acetate dialysis and/or in patients suspected of developing hypoxemia, but it cannot replace direct blood gas measurements in arterial blood samples.
Problems Associated with Pregnancy in Renal Allograft Recipients
Authors: O'Connell P. J. , Caterson R.J. , Stewart J. H. , Mahony J. F.
Published: April 2018

Of 18 pregnancies in 11 renal transplant recipients, three were terminated and in the remaining 15 (in 8 women) there were 10 live births (including one set of twins), five intrauterine deaths, and one spontaneous abortion. Graft function deteriorated in six women, from obstruction of the transplanted ureter in two, recurrent glomerulonephritis in two, rejection in one, and pelvi-ureteric junction obstruction in one. Hypertension worsened or developed in all but one of the pregnancies and proteinuria appeared in eight. Of the 10 live births only one reached 38 weeks gestation (mean 35 weeks) and four neonates were small for gestational age. One infant died early from intraventricular hemorrhage and hyaline membrane disease, one fetus had hydrocephalus, and the others were normal. Factors associated with a poor fetal outcome were deterioration in graft function during pregnancy, pre-existing hypertension, or the development of hypertension before the third trimester
Acute Abdominal Events and Their Impact on Morbidity and Mortality in a CAPD Program
Authors: Chandran P.K.G. , Flynn C.T. , Shadur C.A. , Lane T.M.
Published: April 2018

A retrospective analysis was done to explore the impact of acute abdominal events other than peritonitis, on morbidity and mortality in a CAPD program over a span of 6 years. Subtlety of clinical manifestations and low yield from investigational attempts (except microbiologic) made decision-making as to whether or not to continue CAPD, hard. An increased prevalence of septicemic shock with its inevitable high risk of morbidity and mortality was striking. Timely termination of CAPD and change over to hemodialysis may help to prevent dissemination of infection in these patients. Among the vascular causes of death in CAPD patients, bowel infarction seemed to be the most common.
Plasma Dilution during Transdermal Clonidine Antihypertensive Monotherapy
Authors: Zawada E. T. , Jensen R. A. , Williams L. , Zeigler D.W. , Kauker M.L.
Published: April 2018

In eight hypertensive patients treated with transdermal clonidine for one year, there was plasma dilution, as shown by a reduction in serum sodium, hemoglobin, and serum protein levels. Free water clearance did not change significantly. Plasma dilution was likely sustained by increased water intake due to “dry mouth”, as frequently seen with central acting drugs such as Clonidine.
Light and Electronmicroscopic Examination of Calf Lung Tissue after Left Ventricular Assisted Circulation with the Spindle Pump
Authors: Hager J. , Dietze O. , Brandstaetter F. , Koller I. , Unger F.
Published: April 2018

The influence of the spindle pump, a nonpulsatile blood pump, used as LVAD on calf lung tissue was examined by means of the actual 16th protoype, which was applied in 3 “acute ” tests up to 13 hours of pumping duration and 8 prolonged experiments with pumping periods up to 63 hours. Samples were taken during the operation and after exitus of the test animal and investigated by light and electronmicroscopy. Histological findings of tissue changes could be ascribed to mechanical manipulations and shock-like influences. Regardless of the time of nonpulsatile perfusion this tissue damage remained within an acceptable range, indicating the absence of a deleterious effect of nonpulsatile flow.
Aluminium Bone Deposits in Normal Renal Function Patients after Long-Term Treatment by Plasma Exchange
Authors: Mousson C. , Charhon S.A. , Ammar M. , Accominotti M. , Rifle G.
Published: April 2018

The accumulation of aluminium (AI) can cause AI bone deposits, osteomalacia and encephalopathy. As albumin solutions used as replacement fluid in plasma exchange (PE) are contaminated with AI, we studied AI overload in two symptomless patients with normal renal function, treated by long-term plasma exchange (PE). Total AI loading was calculated at 1750 μmol in patient 1 (178 PE sessions) and 2100 μmol in patient 2 (153 PE sessions). Bone biopsy showed AI deposits and low bone formation without osteomalacia in patient 1 and only osteoporosis in patient 2. Plasma AI levels were useless in detecting early AI overload, because the remained in the normal range, even after PE in both patients. Bone biopsy was the best means of recognizing AI intoxication, but cannot be recommended for frequent evaluations. However, the desferrioxamine mobilization test can be proposed as a repetitive non-invasive investigation method.
Defibrotide in Extracorporeal Circulation on Healthy Rabbits
Authors: Marsili M. , Lorenzi P. , Librenti M. , Doni L. , Benassai C. , Martini E. , Fabbri L.P. , Cinotti S. , Morfini M. , Boncinelli S.
Published: April 2018

Defibrotide, a partially depolymerized DNA fraction obtained from mammalian lung, was found to have significant antithrombotic and fibrinolytic activities. On the basis of this evidence defibrotide could be of clinical value during hemoperfusive treatment. The present study was designed to evaluate the biological tolerance of this technique in a model of extracorporeal circulation, using an original Silastic apparatus, with defibrotide (0.83 mg/kg–1/min–1 after a 50 mg/kg–1 bolus injection) and heparin (0.66 IU/kg–1/min–1 after a 400 IU/kg–1 bolus injection) in ten rabbits (Group 1) and heparin only in ten others (Group 2, control group). In this study defibrotide produced a significantly lower pressure inside the circuit compared to the control group and gave a protective effect against those pathological changes which appeared during extracorporeal circulation and that may be considered omens of a state of shock. However the use of defibrotide in addition to heparin seemed to have a poor effect on platelet and leukocyte count alterations during application of this technique.
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
Insulin Delivery by Implanted Pumps: One-Year Trial with Programmable Infusion Systems (The Point Study)
Authors: Walter H.
Published: April 2018

A feasibility trial was carried out in four European centers to test the safety and efficacy of stabilized insulin (HOE 21GH) in twenty remote-controlled infusion pumps (Siemens AG) implanted in twenty type I diabetic patients. Fifteen had been implanted with intraperitoneal and five with the intravenous access route. Total observation time was 18.2 patient years. A total of 36,077 self blood glucose measurements were collected from the patients. Of these 62.9% were in the acceptable range of 70–160 mg/dl. Symptomatic hypoglycemias were rare and reported in a frequency of 2.6 per patient months; of these 0.22 per patient year required medical attention. The median of HbA1c was in the upper normal range or slightly above. Three pumps had to be explanted prematurely because of surgical and technical problems. Although some technical and clinical problems were still observed, the study shows the successful clinical use of implanted, remote-controlled dosing devices and the special insulin preparation stabilized with polyethylene-polypropylene-glycol (Hoechst AG).
Flow Rate Dependence of in vitro Removal of Anti-A and Anti-B Antibodies by Immunoadsorbents with Synthetic Oligosaccharides Representing Blood Group Substances
Authors: Kaplan M. , Mazid M.A.
Published: April 2018

In vitro removal of anti-A and anti-B antibodies by immunoadsorbents with synthetic oligosaccharide structures representing blood group substances have been studied under controlled and simulated extracorporeal perfusion conditions at different flow rates ranging from 20 to 160 mL/min. There is a gradual decline in antibody titers in the plasma, as it relates to the antibody binding capacity and efficiency of the immunoadsorbents, both as a function of time and plasma volume at any of the flow rates employed. Approximately the same maximal binding capacity is achieved in about 4 hours of perfusion regardless of the flow rate, whereas increased number of plasma volumes are required at higher flow rates to compensate for the appropriate residence times needed in the column to utilize the same capacity. The perfusion time alone appears to be a critical factor which via the flow rate determines the residence time between the plasma and the immobilized hapten in the column. Also, the optimal flow rate at which maximum binding capacity of the immunoadsorbent may be utilized efficiently appears to fall within a range of the flow rate. The factors determining this range and the efficiency of the immunoadsorbents under dynamic conditions are discussed. The results obtained under the controlled conditions and the discussions that follow are expected to be generally useful, at least, as approximate clinical guidelines, for selective removal of specific substances by extracorporeal perfusion techniques utilizing therapeutic intervention with immunoadsorbents in this important area of medical therapy
Transport Functions in a Bioartificial Kidney under Uremic Conditions
Authors: Uludag H. , Ip T. K. , Aebischer P.
Published: April 2018

A bioartifical kidney, a confluent monolayer of renal tubular cells attached to a permselective synthetic membrane, may some day substitute for the failing renal function. In such a device, the cells would have to exhibit transport properties when exposed to uremic plasma. To test the feasibility of a bioartificial kidney, LLC-PK1 cells derived from the proximal tubule were grown to confluence on microporous, cellulose nitrate membranes and transepithelial transport of inulin, glucose and tetraethylammonium (TEA) was investigated with standard tissue culture medium and with the hemofiltrate obtained from a uremic patient. Inulin, which is neither reabsorbed nor secreted by renal epithelial cells, did not diffuse through the LLC-PK1 monolayer in either tissue culture fluid or hemofiltrate. Glucose was preferentially reabsorbed and TEA was preferentially secreted in both media. In hemofiltrate, LLC-PK1 cells reabsorbed glucose at the same rate as in tissue culture fluid but secreted TEA at a significantly higher rate. This difference was related to the pH of the fluids since it was abolished by correction to the same pH value. For both solutes, the passive transepithelial leakage was significantly lower in hemofiltrate. We conclude that LLC-PK1 cells retain their reabsorbtive and secretory transport characteristics under uremic conditions.
Monitoring of Blood Gases during Extracorporeal Circulation with an Artificial Lung
Authors: Lautier A. , Gaillard D. , Juvin A.M. , Gille J.P. , Sargentini J.C. , Dehe T.
Published: April 2018

During cardiopulmonary bypass, the heart-lung machine and the patient's gas exchange systems (uptake and elimination) form an undissociable couple. Changes in one of the components lead to corresponding changes in the other. In the artificial lung, like in the natural lung and peripheral tissues, gas exchanges depend on several parameters: blood inlet conditions, blood flow rate, temperature, composition of the gas mixture used for ventilation, blood tissue perfusion, O2 consumption, etc. The perfusionist's primary objective is to obtain from the artificial lung adequate O2 delivery to and CO2 removal from the tissues. This paper discusses the main parameters which must be taken into account and analyses the main sensors currently available for in-line measurement of blood gases.
Clinical and Laboratory Evaluation of Hemocarboadsorption in Autoimmune Bullous Dermatoses
Authors: Grando S.A. , Drannik G.N. , Glukhenky B.T. , Kostromin A.P. , Romanenko A.B. , Chayun O.A. , Chernyavski A.I.
Published: April 2018

Hemocarboadsorption (HCA) with the following immunosuppressive therapy was used to treat 48 patients with pemphigus vulgaris (PV) and 31 patients with bullous pemphigoid (BP) in the acute phase. The levels of autoantibodies, eicosanoids, endoproteases and their inhibitors as well as interleukin (IL) 1 and IL 2 production and absorption of exogenous IL 2 were examined in the treatment dynamics. The therapeutic effect of HCA was displayed in prompt disease remission in 43 PV and 29 BP patients. Clinical improvement was accompanied by antibody elimination and interleukin cascade reaction normalization. HCA resulted in growth of patients’ serum immunosuppressive activity. It was concluded that HCA has some immunoregulatory effect.
In Vitro Evaluation of Left Ventricular Assistance by Cannulation of Both Femoral Arteries
Authors: De Paulis R. , Engelhardt H. , Chiariello L. , Reul H. , Morea M.
Published: April 2018

The possibility of achieving effective mechanical ventricular assistance without the need for thoracotomy provides great clinical advantages. Two in vitro systems were used to assess left ventricular unloading by means of a small-diameter cannula inserted retrograde into the left ventricle by cannulation of the femoral artery. This cannula is connected to the inlet of a centrifugal blood pump (CP) that delivers the blood into the controlateral femoral artery. Steady-flow test circulation was used to pump fluid in a closed loop from a reservoir through the test cannula back into the reservoir. Pressure drops over cannulae with inner diameters of 4, 5, 6, 7, and 8 mm at flows of 2, 2.5, 3 L/min, against a pressure of 60, 80, 100, and 120 mmHg were calculated. A stationary pressure drop of 120 mmHg was measured at a flow of 3 L/min through a 100 cm cannula with an inner diameter of 6 mm. The second system was a pulsatile mock circulation composed of an atrial and an arterial reservoir linked by a pneumatic prosthetic ventricle. This system was coupled with a 100 cm cannula, 6.1 mm inner diameter, which was passed across the outflow valve of the pulsatile prosthetic ventricle and connected to a CP. Fluid was withdrawn from the ventricle and pumped back into the arterial reservoir. Pulsatile pressure drop over the cannula was measured at different CP flows for increasing systolic ventricular pressure; heart unloading was quantified as a function of CP flow under baseline and failing conditions of the prosthetic left ventricle model. At a constant CP flow the pressure drop over the cannula increased with the pulsatility inside the ventricle. The work of the prosthetic ventricle was reduced by more than 50% when the CP pump was set to 3 L/min; at the same flow setting, when the situation of a failing left ventricle was simulated, the CP was able to take over all the work of the prosthetic ventricle, establishing a stationary flow and a 25% higher mean aortic pressure. This approach to left ventricular assistance may have significant clinical relevance.
Protein Adsorption and Cellular Adhesion and Activation on Biomedical Polymers
Authors: Anderson J.M. , Bonfield T.L. , Ziats N.P.
Published: April 2018

The design and development of new biomedical polymers for clinical application in devices, prostheses, and artificial organs requires a basic and fundamental understanding of biological interactions with biomedical polymers. Efforts in our laboratory have been directed towards appreciating the humoral and cellular interactions which govern protein adsorption and cellular adhesion and activation on biomedical polymers. Information and data are presented on protein adsorption from whole human blood, complement activation and receptors, and monocyte/macrophage adhesion and activation with growth factor release. Supported by experimental evidence, concepts regarding protein/polymer, cell/ polymer, cell/protein/polymer, and cell/cell interactions as they are related to in vivo events are presented.
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.
Immune Response to a Recombinant Hepatitis B Vaccine in Hemodialysis Patients
Authors: Docci D. , Cipolloni P.A. , Baldrati L. , Capponcini C. , Turci F. , Feletti C.
Published: April 2018

A 20-μg dose of a recombinant hepatitis B vaccine was given at 0, 1, 2 and 6 months to 24 hemodialysis patients. From month 7 (i.e., 1 month after the fourth injection), 58.3% (14/24) of the patients had developed protective levels of antibodies against hepatitis B surface antigen (anti-HBs). In patients responding to vaccination, the fourth injection led to an abrupt rise of the anti-HBs titres which reached their maximum 2 months later, that is, in month 8. At that time, the geometric mean titre of anti-HBs was 145.79 mlU/ml. Eighteen months after the start of vaccination, 50% (12/24) of the patients were maintaining protective levels of anti-HBs antibodies. It is noteworthy that these results could be obtained with a considerably lower dosage than previously recommended.
Magnetic Resonance Imaging of the Bone Marrow following Treatment with Recombinant Human Erythropoietin in Patients with End-Stage Renal Disease
Authors: Jensen K.E. , Stenver D. , Jensen M. , Sørensen P. Grundtvig , Karle H. , Thomsen C. , Henriksen O. , Nielsen B.
Published: April 2018

We used magnetic resonance imaging (MRI) to study vertebral bone marrow in hemodialysis patients during treatment with recombinant human erythropoietin (rHuEPO). We found changes in T1 relaxation times and image contrast within 14 days after starting treatment, before any response was seen in the hemoglobin concentration in peripheral blood. The increase in T1 relaxation times, together with earlier reported changes observed with localized magnetic resonance spectroscopy, indicate an alteration in cellular composition of the hemopoietic bone marrow with an increase in the amount of hemopoietic active tissue. MRI may be a useful, non-invasive way of evaluating bone marrow response to different modes of rHuEPO administration and dosage.
Activity of Type 1 Erythrocyte Complement Receptors in Uremia and after Renal Transplantation
Authors: Klinger M. , Słowik E. , Kopeć W. , Szewczyk Z.
Published: April 2018

The effect of uremia on the activity of the erythrocyte complement receptors type 1 (CR1), and the changes occurring after renal transplantation, were studied. The complement receptor activity was measured by immune adherence utilizing a rosette technique. Patients with terminal kidney failure on the hemodialysis program exhibited significantly lower values of the erythrocyte CR1 activity in comparison with healthy controls. The circulating immune complexes did not affect erythrocyte CR1 activity. After successful renal transplantation, irrespective of the immunosuppressive program used, a significant increase in erythrocyte CR1 activity appeared, similar to control group values. However, the activity of erythrocyte CR1, in the graft recipients under cyclosporin A treatment, was significantly higher than in the patients receiving azathioprine with prednisone. Therefore, it is possible that cyclosporin A, transported in the erythrocytes, modifies the complement receptor function.
Raster-Electron-Microscopic Investigations in Large-Bore Catheters for Extracorporeal Detoxification
Authors: Bambauer R. , Mestres P. , Piroung K.J.
Published: April 2018

Large bore catheters (n = 42, 31 patients) which remained in position for a period of between 2 to 73 days ([Formula: see text] days/patients) were investigated with raster electron-microscopy (scanning electron micrographic: SEM) and for bacterial colonisation. Microbiological findings indicated colonisation of the intravascular large bore catheters in 8 out of 42 catheters (19%). SEM morphological investigation showed bacterial colonisation in only 3 catheters (7%). The 3 different catheter materials had small deposits of fibrin and protein on the inner and outer surfaces after 2 days. This second layer covered the entire surface after 3 days and increased to a thickness of 3-60 μm in the following days. In this matrix erythrocytes, thrombocytes and granulocytes could also been seen.
Cardiopulmonary Dynamics during Pumpless Arteriovenous Bypass for Respiratory Assistance
Authors: Awad J. , Rao T.J. , Deslauriers J. , Martin L. , Lautier A. , Guidoin R.
Published: April 2018

The effect of a pumpless arteriovenous bypass with a microporous membrane oxygenator (MO) on the cardiopulmonary dynamics of dogs revealed an increase in cardiac output and cardiac work proportional to the increase in extracorporeal blood flow. Several current MOs offer so little resistance to blood flow that shunt flows exceeding a third of the normal cardiac output can easily be obtained. This should be enough for CO2 extraction covering metabolic production, and would add a non negligible amount of O2 to the blood
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.
Non-A, Non-B Hepatitis and Anti-HCV Antibodies in Dialysis Patients
Authors: Gilli P. , Moretti M. , Soffritti S. , Marchi N. , Malacarne F. , Bedani P.L. , De Paoli Vitali E. , Fiocchi O. , Menini C.
Published: April 2018

To define the prevalence of non-A, non-B hepatitis, antibodies to HCV were detected in 193 patients on renal replacement therapy (52 transplant and 141 hemodialysis patients) and in 50 staff members of a Nephrology Department. Unequivocal seroconversion was documented in 5 transplant (9.6%) and in 26 dialysis patients (18.4%). In the dialysis population, the prevalence of anti-HCV antibodies was evaluated in patients grouped according to the number of blood transfusions and to the different sections of dialytic treatment. The most striking findings were the marked differences in the prevalence of anti-HCV antibodies among patients treated in different sections (from 0% to 70%), and the presence of a significant increase in alanine-amino-transferase (ALT) concentrations in 14 anti-HCV negative patients. The results suggest that the diffusion of non-A, non-B hepatitis is mainly transfusion-related, with the possibility of significant environmental diffusion related to the violation of infection-control measures. The current immunoassay is probably unable to detect the actual frequency of the infection.
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.
Effects of Chronic Renal Failure and Hemodialysis on Plasma Glomerulopressin
Authors: Zhou X.J. , Vaziri N.D. , Kaupke C.J.
Published: April 2018

Glomerulopressin (GP) is a small molecular weight hepatic hormone which increases glomerular capillary pressure and enhances glomerular filtration rate (GFR) in experimental animals. Protein ingestion, glucagon secretion and volume expansion raise plasma GP activity. Effects of end-stage renal disease (ESRD) and hemodialysis (HD) on GP activity are unknown. We measured plasma levels and HD clearance of GP in eight ESRD patients and four normals. Predialysis plasma GP in the ESRD group was significantly higher than in the control group (p < 0.01). Plasma GP activity was significantly lowered by HD (p < 0.01). GP activity of hemofiltrate averaged 38.1% of that in the predialysis plasma. Single passage through the dialyzer resulted in a significant fall in plasma GP activity (p < 0.001). Dialyzer clearance of GP was 143.8 ± 73.4 ml/min, representing 75.4% of that of urea. Conclusions: a) plasma GP activity is elevated in ESRD, due probably to increased production (volume expansion) and reduced renal elimination, b) GP is readily removed by HD and c) the fall in plasma GP postdialysis is due to removal by dialysis and possibly reduced hepatic release with the correction of hypervolemia.
Automatic, Noninvasive Intradialytic Clearance Measurement
Authors: Polaschegg H.D.
Published: April 2018

The feasibility of non invasive, automatic intradialytic measurement of effective clearance is demonstrated by a mathematical derivation. In a practical setting the conductivity difference between dialysate inlet and outlet of the dialyzer is measured for two different dialysate inlet concentrations. This allows for the calculation of the electrolyte dialysance, which is equal to the effective urea clearance, provided dialysate flow, blood flow and blood electrolyte composition remain unchanged during the measuring interval
Biotrans: Description of a Data Transfer Program for the Biostator
Authors: Heinemann L. , Heise T. , Kamper K.
Published: April 2018

Glucose clamp experiments are often performed by means of a Biostator. Due to the fact that this device does not provide data storage, data analysis has to be done manually or data must be fed into the computer. In order to enhance the efficacy of data analysis and to avoid time consuming work, a data acquisition program (Biotrans) has been developed which allows data transfer from the Biostator into an IBM compatible computer. After a complex analysis of incoming data, Biotrans provides on-line data storage and display features (blood glucose concentrations and glucose infusion rate). Off-line analysis of the stored data is accomplished by conventional spread sheet programs, thus permitting complex data calculations and graphic presentation. In more than 300 glucose clamp experiments performed within the last three years Biotrans was an important tool providing data storage capabilities, better control of ongoing events during an experiment and rapid and reliable data analysis immediately after completion of individual experiments.
Evaluation of Collagen Modification and Surface Properties of a Bovine Artery via Polyepoxy Compound Fixation
Authors: Wang E. , Thyagarajan K. , Tu R. , Lin D. , Hata C. , Shen S.H. , Quijano R.C.
Published: April 2018

Collagen of bovine internal thoracic artery (BITA) was treated with glutaraldehyde (GA) or polyepoxy compounds (PC). This study was to evaluate the surface properties as a result of tissue tanning reaction with PC. The fixation resulted in a significant reduction of available lysine, histidine, and other amino acid residues in PC fixed grafts as compared to fresh pre-fixed arteries. Among them, the lysine (Lys) content was reduced by about 80%, indicating that PC reactions mainly involve with Lys residues. Both PC and GA treatment led to crosslinking as evidenced by the increase in the denaturation temperature. The critical surface tension and the Fourier Transform Infrared Spectrum (FTIR) on a preimplant and its 96 days explant were evaluated and found to be similar. The FTIR analysis of a pre-implant and the 96 day explant indicated that there was no lipid deposition.