bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physicochemical and Pharmacological Comparison of Pyridoxylated Hemoglobin Bound to Polyoxyethylene or Polymerized by Glutaraldehyde
Authors: Menu P. , Mouelle P. , Clerc Y. , Labrude P. , Vigneron C. 
Published: March 2018

Two modified hemoglobin solutions were assessed using the same physico-chemical and pharmacological techniques. The first was prepared by covalent binding of monomethoxypolyoxyethylene (MPOE) 1.9 kDa to pyridoxylated hemoglobin (PLP-Hb). The resulting conjugate had a molecular size of 100 kDa (MPOE-PLP-Hb). The solution was cleared of non-fixed MPOE through ion exchange chromatography on Spherodex, thus bringing viscosity and oncotic pressure back to physiological values. The second was prepared by limited polymerization of pyridoxylated hemoglobin with glutaraldehyde (POLY-PLP-Hb). Tangential flow ultrafiltration achieved a satisfactory polymer/oligomer return. Quality controls showed no difference between the solutions. Total isovolemic exsanguinotransfusions in the rat did not help differentiate the two solutions. Hemorrhagic shock (80% of blood volume, rat) gave definitive survival for 8 of the 14 animals tested with MPOE-PLP-Hb (57%) but only 3 of the 8 animals tested with POLY-PLP-Hb (38%). None of the chemical approaches to reduce hemoglobin loss proved any more efficient than another, with the evaluation techniques employed.
An Equation for Calculating Postdialysis Plasma Sodium
Authors: Lopot F. , Bláha J. , Válek A. 
Published: March 2018

Well defined dry weight is a must for adequate UF control during haemodialysis (HD). However, interdialytic weight gain (ΔBW) must not be excessive. ΔBW is closely related to interdialytic thirst which in turn is strongly influenced by postdialysis plasma sodium (CPNapost), but little is known about the desired CpNapost. The points below serve as a basis for establishing this value. a) Thirst is mediated by osmoreceptors. b) A strong correlation has been found between ΔBW and intradialytic increase in plasma sodium but no such correlation exists with the interdialytic increase in plasma urea. This indicates that fluid intake between dialyses depends solely on electrolytes. c) Pre-dialysis plasma sodium in an individual is stable, indicating that the patient is at his “set value” of electrolyte osmolality. d) Half of the potassium removed during HD comes from the extra- and half from the intracellular space. Assuming that it is desirable not to disturb a patient's predialysis osmotic steady state, it can be calculated that the desired CPNapost should be higher than the predialysis value by half of the intradialytic plasma potassium drop, i.e., approx. CPNapost = CPNapre + 1 to 2 mmol/l.
A Modular Mock Circulation for Hydromechanical Studies on Valves, Stenoses, Vascular Grafts and Cardiac Assist Devices
Authors: Schima H. , Baumgartner H. , Spitaler F. , Kūhn P. , Wolner E. 
Published: March 2018

Devices for hydrodynamic simulation are required in a variety of studies such as device evaluation, cardiovascular modeling and for student training. Most studies today use different, incompatible circuits, which must be redesigned for every new application. To obtain a universal apparatus, a unitized system with standard connectors was developed. Three types of connectors were selected: 1″ flange connectors, ½″ tubing connectors and Luer-connectors with a 2 mm lumen. The complete system consists of reservoirs, throttles, valve holders, adapters for Doppler ultrasound probes, and converters to link these basic diameters. The apparatus can be driven by membrane, centrifugal and geared pumps. The system has successfully been used in echocardiographic studies of stenosis and valvular insufficiency, for pulse propagation in vascular grafts, and to test the hydraulic performance of cardiac assist devices. Flow rates between 0.1 and 30 l/min and pressure gradients up to 250 mmHg were achieved. In practical use, the system can be adapted to suit various investigations, with minimal expense. Standardization of the parts and connectors results in simple documentation and good reproducibility.
Prolonged Extracorporeal Circulation for Acute Myocarditis
Authors: Moreno-Cabral C.E. , Moreno-Cabral R.J. , McNamara J.J. , Dembitsky W.P. , Adamson R.M. 
Published: March 2018

Total circulatory support for acute reversible myocardial failure is rarely used in clinical situations outside the postoperative period following cardiac surgery. We treated an 8-year-old girl who suffered acute viral myocarditis and sustained cardiac arrest requiring cardiopulmonary bypass for resuscitation. This was accomplished with the use of the portable cardiopulmonary support system (CPS), which consists of a centrifugal pump and a membrane oxygenator. This patient was placed on CPS in Hawaii and transported after 3 days to San Diego (4200 km) for further mechanical support and possible heart transplantation. Adequate cardiac function returned and CPS was stopped after 6 days. She is alive and well, attending school two and a half years after the event. Prolonged use of CPS for acute myocardial failure outside the operating room, including long distance transportation, is effective and easily accomplished with currently and widely available equipment, and should be used in acute, reversible catastrophic heart disease
Gait restoration in a spinal cord injured subject via neuromuscular electrical stimulation controlled by an artificial neural network
Authors: Sepulveda F. , Granat M.H. , Cliquet A. 
Published: March 2018

Attempts to restore gait in spinal cord injured subjects have stumbled on control difficulties associated to the neuromuscular system's non-linearity and time-variance. Thus, a simple auto-adaptive artificial neural network has been devised to control gait swing generation by means of neuromuscular electrical stimulation. Both theoretical and experimental approaches were taken. The computer-based system consisted of a three-layer artificial neural network that read angular data from the hip, knee and ankle joints. The output signal consisted of variations on the applied stimulation pulse width. Surface electrical stimulation was applied to the femoral and peroneal nerves of one leg. Neural network training included off-line supervised learning schemes. The system was tested on a male subject with an incomplete C6-level lesion. Several tests were run to determine whether the off-line trained neural network could correctly control the motion. The effect of on-line learning upon the control performance was also evaluated. The system was found to control the motion with success only at times. Control performance was found to improve in response to the application of on-line learning. Learning stability following on-line learning was found to be satisfactory. In a final test, the artificial neural system had appropriate responses to an initial perturbation, which suggests that further research in this area should be pursued. (Int J Artif Organs 1998; 21:49–62)
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: March 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.
Effects of Zinc Supplementation on the Immune System and on Antibody Response to Multivalent Influenza Vaccine in Hemodialysis Patients
Authors: TüRK S. , Bozfakioglu S. , Ecder S.T. , Kahraman T. , GüREL N. , Erkoç R. , Aysuna N. , Türkmen A. , Bekiroglu N. , Ark E. 
Published: March 2018

The depression of the immune system in chronic uremia is a well-known phenomenon but the role of serum zinc (Zn) levels on both cell-mediated and humoral immunity is still controversial. The aim of this study was to investigate the effect of Zn supplementation on the immune system and on antibody response to multivalent influenza vaccine (MIV) in hemodialysis patients (HP). Twenty-six HP and 11 healthy subjects (HS) were vaccinated with MIV. Hemodialysis patients were randomly divided into two groups. Group 1 (13 HP) was supplemented with 120 mg ZnS04 after each dialysis session. Group II (13 HP) and Grouip III (11 HS) were given placebo. In all cases, the serum Zn levels, CD3, CD4, CD8, CD19, HLA-DR+ cell percentages, CD4/CD8 ratio and CD3+HLA-DR+ cell percentages were determined before and 30 days after vaccination. Antibody levels to subgroups of MIV were also measured. All the baseline parameters studied were not statistically different between Group I and II. However, there was a significant difference between the basal parameters of Group III and the other two groups, except for CD3 and CD4 cell percentages. Serum Zn, CD19 cell percentage and antibody levels to MIV subgroups were significantly increased in Group I at the end of the first month of the study (p<0.01, p<0.05, p<0.001, p<0.001, and p<0.01, respectively), but the other parameters showed no significant changes. The only significant change observed in Groups II and III was an increase in antibody levels to MIV subgroups one month after vaccination. Antibody levels to MIV subgroups, were not statistically different between Groups I and II, but in Group III they were strikingly higher than those of HP (p<0.001). These results led us to conclude that Zn supplementation could not restore the immune parameters and enhance antibody response to MIV in HP.
Biocompatibility Evaluation of Polyamide Hemofiltration
Authors: Panichi V. , Bianchi A.M. , Andreini B. , Casarosa L. , Migliori M. , Depietro S. , Taccola D. , Giovannini L. , Palla R. 
Published: March 2018

Introduction Postdilution hemofiltration with a polyamide membrane is a renal replacement technique widely used, but very little information is available regarding the biocompatibility of this treatment. In this paper we report the results of an acute study of the biocompatibility of polyamide hemofiltration. Patients and methods Complement activation such as C3a and C5a Des Arg (RIA), granulocyte degranulation like alpha 1 elastase intradialytic increase (ELISA) and the expression of high affinity membrane receptors for IL-2 (anti-TAC) were determined. Beta 2-microglobulin (RIA) intradialytic decrease, as well as its convective removal, was evaluated. The nature of protein layer adsorbed onto the polyamide membrane, at the end of the dialytic session was investigated with a new immunohistochemical tecnique. Cell-associated cytokine concentration (like IL-1 beta and IL-1Ra - ELISA) was determined on mononuclear cell lysates. Results A low degree of complement activation was detected with the polyamide membrane when data were adjusted for hemoconcentration and for 1 m2 of membrane surface area. An important convective removal not only of Beta 2-microglobulin (258±20 mg/session), but also of the activated anaphylatoxins (225±76 ng/ml for C3a and 22.5±4 ng/ml for C5a) was revealed. A marked deposition of all coagulation factors with no detectable amount of immunoglobulins and complement factors was revealed on the polyamide membrane at the end of the dialytic session. No intradialytic (for IL-1beta) (from 14.1±3.0 to 13.5±2.9 pg/ 2.5 x 106 cell) and interdialytic (for IL-1Ra) (from 4572±1076 to 5408±615 pg/ 2.5 x 106 cell) cell-associated cytokine expression was induced by hemofiltration. Discussion and Conclusion Polyamide hemofiltration is a highly biocompatible technique due to the use of a synthetic membrane with a sterile reinfusion fluid and the convective removal of the activated anaphylatoxins and Beta 2-microglobulin.
Fever in Dialysis Patients with Recently Rejected Renal Allografts
Authors: Sever M.Ş. , TüRkmen A. , Yildiz A. , Ecder T. , Orhan Y. 
Published: March 2018

Introduction Fever of unknown origin is a complex problem in dialysis patients with recently rejected renal allografts, due to the contribution of the newly withheld immunosuppressive agents to the immunosuppression of uremia, resulting in an atypical presentation of infections, a main cause of fever in these cases. Materials and Methods Two dialysis patients with recently rejected renal allografts who were hospitalized because of fever of unknown origin are reported. Biochemical, bacteriological and imaging studies were performed for specific diagnosis. Results Extensive laboratory investigations failed to yield any diagnosis and allograft nephrectomy was performed in one patient, with a probable diagnosis of inflammation of the allograft, which resulted in no improvement. Eventually, both patients were found to have adrenal insufficiency responsible for the fever, which improved after steroid replacement. Conclusions Adrenal insufficiency should be suspected in all dialysis patients presenting with fever and atypical symptoms, but only after other potential causes are eliminated; since steroid administration may normalize fever regardless of the etiology, it may mask the signs and symptoms and delay the treatment of other (if any) underlying disorder(s).
Conductivity: On-Line Monitoring of Dialysis Adequacy
Authors: Del Vecchio L. , Di Filippo S. , Andrulli S. , Manzoni C. , Corti M. , Barbisoni F. , Locatelli F. 
Published: March 2018

Cardiovascular disease and the inadequacy of delivered dialysis are the main factors determining morbidity and mortality in dialysis patients. We have already demonstrated that a conductivity kinetic model makes it possible to match interdialytic sodium loading and intradialytic sodium removal (the main factor determining cardiovascular morbidity) without the need for blood samples and, thus, in routine clinical practice. The aim of the present study was to test the possibility of using the conductivity method also to determine Kt/v without blood or dialysate sampling. In 18 steady-state patients, the urea distribution volume (V) was kinetically determined once using ionic dialysance (D) values instead of those of effective urea clearance. One month later, the Kt/V was determined by using the current D and T values and the predetermined V (Dt/V), then compared with the equilibrated Kt/V computed by means of the SPVV kinetic model (eqKt/V). The mean value of Dt/V was 1.18 ± 0.15; while of eqKt/V it was 1.18 ± 0.16, with a mean difference of 0.00 ± 0.07. The conductivity method therefore seems to be very promising not only for monitoring the sodium balance, but also for quantifying delivered dialysis. Since its simplicity and low-cost make it suitable for use at each dialysis session, the conductivity method could therefore lead to significant progress in dialytic practice by contributing to the elimination of the two main causes of morbidity and mortality in dialysis patients.
Chronic Hemodialysis: Kt/V or Solute Removal Index to Evaluate the Effective Delivered Dose?
Authors: Di Filippo S. , Manzoni C. , Corti M. , Locatelli F. 
Published: March 2018

A standard for quantifying the hemodialysis dose has not yet been defined. Many authors suggest the use of an alternative method to Kt/V: the solute removal index (SRI). We compared three methods based on blood-side urea determinations with the direct quantification method (DDQ) for estimating the delivered dialysis dose, expressed as SRI as well as Kt/V. Eight patients underwent three consecutive dialysis sessions, with the same dialytic efficiency. For each patient and each dialytic session the SRI and Kt/V were determined using the DDQ method and the single pool variable volume kinetic model, in its classical version (SPVV) as well by using the post-dialysis urea value determined 30 min after the end of the session (eqSPVV). Double pool Kt/V was also estimated by the Daugirdas-Schneditz rate equation. Our results showed that the SPVV kinetic model significantly overestimated the delivered dialysis dose, the mean value of SRI and Kt/V were respectively 8.9% and 17% higher than those obtained by DDQ. The eqSPVV allowed the SRI to be estimated with a difference of -0.3% and Kt/V with a difference of -2% in comparison with DDQ. By using the Daugirdas-Schneditz rate of equation, which does not require blood samples to be drawn after the end of the session, the difference in Kt/V value was 3%. Therefore, both the eqSPVV kinetic model and the Daugirdas method allow quantification of the delivered dialysis dose with results similar to those determined by DDQ, which cannot be routinely applied. Kt/V seems the best marker for dialytic doses quantification.
In Vitro Thrombogenicity Testing of Artificial Organs
Authors: Paul R. , Marseille O. , Hintze E. , Huber L. , Schima H. , Reul H. , Rau G. 
Published: March 2018

Thromboembolic complications remain as one of the main problems for blood contacting artificial organs such as heart valves, bloodpumps and others. In vitro evaluation of thrombogenesis in prototypes has not previously been part of the standard evaluation of these devices. In comparison to hemolysis testing, evaluation of the thrombogenic potential is more difficult to perform because of the complexity of the blood coagulation system. We present an in vitro testing procedure that allows the accelerated examination of the thrombogenic potential of different types of blood pumps. Additionally, first results are presented that indicate the reliability of the accelerated clotting test for mechanical heart valves. Results for the centrifugal pump BioMedicus and two microaxial pumps have shown typical thrombus formation at locations such as bearings. The results indicate that the accelerated clotting test is an excellent addition to the much more expensive animal testing of artificial organs or assist devices. In vitro testing permits studies of thrombus formation to be performed at an early stage and at low costs and also facilitates a more precise investigation of device areas known to be potential hot spots for thrombus formation.
Quality of Life and End Stage Renal Disease Therapeutic Programs
Authors: Mingardi G. ,   For the DIA-QOL Group, Mingardi G. , Marchesi D. , Perticucci E. , Rota S. , Tiraboschi G. , Cornalba L. , Brunzieri C. , Foroni I. , Lupi G. , Cortinovis E. , Ondei P. , Alongi G. , Lorenz M. , Apolone G. , Mosconi P. , Ruggiata R. 
Published: March 2018

Because patients with ESRD cannot be cured of their underlying conditions and because the therapeutic programs have an important impact on the patients’ life style, the patient's own assessment of health should have a central place in clinical care. Until now, attention has almost exclusively focused on technical and clinical outcomes, and survival. Functional status, well-being and quality of life, satisfaction with care, or in other words “patient's experience”, have been only marginally considered. There is a growing recognition that use of mortality data alone is not the most effective way to asses the quality of care provided to these patients. Generic and disease-specific health issues can be investigated with the use of questionnaires, by asking questions that cover physical, psychological and social domains. Health related quality of life data regarding chronic renal failure, dialysis and transplantation are briefly presented and discussed. These data show differences between patient's subjective feelings and physician's opinions about patients, between objective quality of life indexes and subjective quality of life scores. A more comprehensive view of our patients seems possible and useful.
Accreditation Manual for Nephrology
Authors: Oliva D. 
Published: March 2018

The IRS did not develop a new theory of accreditation but drew up a methodology for assessing public policies, which internalised accreditation philosophy and was based on a theory of the decision-making process. Two questions underlie this theory: 1) whether health is a professional organisation, a company or a public policy, 2) whether accreditation in the internationally accepted meaning of the term is the most effective system of continuous improvement for this sector as it is organised in Italy. According to the IRS, health is all three of these things and accreditation responds adequately to the complexity of the sector. In fact: a) internalises professional knowledge (and is therefore ideal for a professional organisation); b) it triggers a process of continuous improvement of the product/service supplied (and that is ideal for a company that must maintain the competitiveness of its product/service as high as possible); c. it uses a methodology which highlights the mechanisms of interaction between the actors (a methodology udnerlying decision making theory where there are actors who decide, knowing that they have to find a consensus and who exchange resources in a virtuous circle. The principal qualitative element identified by the IRS methodology was the internalisation by the health system of patients’ expectations and patients’ satisfaction in the welfare process. The main feature of the accreditation methodology designed by the IRS is that the assessment focuses neither on structures (which would have been useful to measure the degree of reliability) nor on the compilation of behaviour guidelines, but is centred on the assessment of a function, on the quality of the provision of a specialist health service. The decision to assess a specialist function (e.g. nephrology) and not a structure (e.g. a nephrology department or a hospital) gives maximum importance to the figure of the professional.