bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mass Preparation of Primary Porcine Hepatocytes and the Design of a Hybrid Artificial Liver Module using Spheroid Culture for a Clinical Trial
Authors: Fukuda J. , Sakiyama R. , Nakazawa K. , Ijima H. , Yamashita Y. , Shimada M. , Shirabe K. , Tsujita E. , Sugimachi K. , Funatsu K. 
Published: March 2018

To isolate a large number of porcine hepatocytes, we originally developed a mass preparation method that combined the usual collagenase perfusion method of a whole liver with a collagenase redigestion method of tissue fragments after liver perfusion. Using a pig of 10kg, collagenase perfusion only resulted in a yield of 63 ± 78 x 108 total cells with a viability of 69.2 ± 25.3 %, but our combined method had a yield of 167 ± 31 x 108 total cells with a viability of 87.9 ± 4.4 % (mean ± SD). Also, the combined method was applied to two pigs of 10kg body weight at the same time, and isolated 387 ± 89 x 108 hepatocytes with a viability of 87.1 ± 6.9 % and a purity of 93.6 ± 2.8 % in 11 experiments. We designed a large multi-capillary polyurethane foam (MC-PUF) packed-bed module containing 1 x 1010 porcine hepatocytes on a clinical trial scale. The porcine hepatocytes in the module formed spherical multicellular aggregates (spheroids) of 200 – 500 μm diameter. Most hepatocytes forming spheroids were viable judged by fluorescein diacetate and ethidium bromide staining. The activities of ammonia removal, albumin secretion and oxygen consumption of the large MC-PUF module were the same as for a small MC-PUF module containing 2 x 108 porcine hepatocytes, and were maintained for at least 9 days of culture. These results show that a large MC-PUF module is successfully scaled up 50 times. In conclusion, we succeeded in developing a mass preparation method of porcine hepatocytes and a large hybrid artificial liver module on a clinical trial scale.
Long Term Clinical and Echocardiographic Results of Isolated Aortic Valve Replacement in Elderly Patients
Authors: De Feo M. , Renzulli A. , Vicchio M. , Onorati F. , Dialetto G. , De Santo L.S. , Corte A. Della , Cotrufo M. 
Published: March 2018

Results after isolated aortic valve replacement with bileaflet prostheses in patients over 70 years old were reviewed. One-hundred-twenty-eight elderly patients were operated on between January 1988 and January 2000. Patients with associated heart disease were excluded from the study. Preoperative data, early and late postoperative mortality, all valve related complications and data concerning anticoagulation status were recorded. Hospital mortality was 9.3%. Mean follow-up time was 60.98±2.23 months. Twelve-year actuarial survival was 69.6±0.08%. Valve related and anticoagulation related complication rates (0.8% and 1.6% respectively) and actuarial freedom (99±0.009 both) were low, as well as the mean interval between consecutive INR checks (18.39±1.90 days) and the mean INR value (2.17±0.135). Late echocardiographic results showed low postoperative mean transprosthetic gradients (15.48±0.94). Bileaftlet prostheses in the elderly can achieve excellent results with a low incidence of anticoagulation related complications and low risk of reoperation. Older age can no longer be considered a contraindication to bileaftlet prosthesis implant.
The Influence of Different Glucose Concentrations in Haemodialysis Solutions on Metabolism and Blood Pressure Stability in Diabetic Patients
Authors: Simic-Ogrizovic S. , Backus G. , Mayer A. , Vienken J. , Djukanovic L. , Kleophas W. 
Published: March 2018

In recent years the percentage of diabetic patients on haemodialysis has increased. Considering the high frequency of intradialytic hypotensive and hypoglycaemic episodes experienced by these patients, it was the aim of the present study to evaluate the influence of different dialysate glucose concentrations (5.5 mmol/L or 11 mmol/L) on blood pressure and glycaemic regulation, using special dialysis equipment - the GENIUS® System. This cross-over, prospective and randomised study, total duration 14 weeks, included 20 diabetic patients on maintenance haemodialysis. Group 1: 9 patients dialysed using dialysate with a glucose concentration of 5.5 mmol/L and after 7 weeks switched to dialysate with a glucose concentration of 11 mmol/L. Group 2: vice versa. Results show a statistically higher number of patients with hypoglycaemic and hypotensive episodes using dialysate with a 5.5 mmol/L glucose concentration. Also, mean serum glucose values were higher during haemodialysis sessions with a glucose dialysate concentration of 11 mmol/L. There were no statistical differences between the groups in laboratory values, HbA1C, insulin doses or in anthropometric parameters. Our results suggest that fewer diabetic patients undergoing haemodialysis using a higher dialysate glucose concentration of 11 mmol/L have hypoglycaemic and hypotensive episodes. Since this dialysate glucose concentration had no influence on lipid or hepatic metabolism, anthropometric parameters and especially HbA1C values in this short-term study, the long term examination of its effects is warranted.
Evaluation of Cartilage Specific Matrix Synthesis of Human Articular Chondrocytes after Extended Propagation on Microcarriers by Image Analysis
Authors: Goepfert Christiane , Lutz Vivien , Lünse Svenja , Kittel Sabrina , Wiegandt Katharina , Kammal Michael , Püschel Klaus , Pörtner Ralf 
Published: March 2018

Background Cell-based technologies for the repair of cartilage defects usually rely on the expansion of low numbers of chondrocytes isolated from biopsies of healthy cartilage. Proliferating chondrocytes are known to undergo dedifferentiation characterized by downregulation of collagen type II and proteoglycan production, and by upregulation of collagen type I synthesis. Re-expression of cartilage specific matrix components by expanded chondrocytes is therefore critical for successful cartilage repair. Methods Human articular chondrocytes were expanded on microcarriers Cytodex 3. The growth area was increased by adding empty microcarriers. Added microcarriers were colonized by bead-to-bead transfer of the cells. The chondrocytes were harvested from the microcarriers and characterized by their ability to synthesize collagen type II when cultivated in alginate beads using chondrogenic growth factors. A semi-automatic image analysis technique was developed to determine the fractions of collagen type II and type I positive cells. Results The expansion of human articular chondrocytes on microcarriers yielded high cell numbers and propagation rates compared to chondrocytes expanded in flask culture for one passage. The proportion of collagen type II positive cells compared to collagen type I synthesizing cells was increased compared to chondrocytes expanded using conventional methods. The matrix synthesis upon treatment with chondrogenic factors IGF-I and BMP-7 was enhanced whereas TGF-β had an inhibitory effect on microcarrier expanded chondrocytes. Conclusions Expanding human articular chondrocytes on microcarriers omitting subcultivation steps leads to superior ratios of collagen type II to type I forming cells compared to the expansion in conventional monolayer culture.
Feasibility of Monte CarlO simulations in Quantitative Tissue Imaging
Authors: Maeder Ulf , Schmidts Thomas , Avci Ersin , Heverhagen Johannes T. , Runkel Frank , Fiebich Martin 
Published: March 2018

Purpose The feasibility of Monte Carlo simulations as a tool to facilitate quantitative image analysis is investigated by means of simulating light transport in skin phantoms. Methods A Monte Carlo tool is used to compare if simulated fluorescent signals show agreement with measured data. The lipophilic fluorescent probe Nile Red and dedicated skin phantoms are also used in simulations to investigate the influence of the optical properties of the skin on the signal. Results It is shown that the simulated and measured fluorescence signals show linear behavior up to a certain concentration of Nile Red. The simulations of the skin phantoms show the varying influence of single skin layers on the fluorescence signal. A calibration factor for quantitative analysis can be determined for the different skin layers. Conclusion Characterizing the influence of different media on imaging signals is a primary task in developing quantitative analysis methods. Monte Carlo simulations are a useful tool to investigate imaging properties of biological specimen where quantifying signals is important. However, detailed models must be provided.
Off-Label use of Stretchable Polytetrafluoroethylene: Overexpansion of Synthetic Shunts
Authors: Verbelen Tom O. , Famaey Nele , Gewillig Marc , Rega Filip R. , Meyns Bart 
Published: March 2018

Purpose To describe our experience with balloon dilatation and stenting of modified systemic-to-pulmonary artery (PA) shunts in relation to an assessment and interpretation of the mechanical properties of thin-walled expandable polytetrafluoroethylene (ePTFE) stretch vascular grafts. Methods Our pediatric cardiology/cardiac surgery database was reviewed to identify all infants and children with a modified systemic-to-PA shunt who underwent cardiac catheterization. Reports and images were reviewed. Thin-walled stretchable and regular Gore-Tex® vascular grafts were mechanically compared using tensiometry. Results 11 patients underwent dilatation or stenting procedures of a systemic-to-PA shunt. No major complications occurred and none of our patients died during or due to this intervention. High pressures in balloons and stents with diameters larger than the graft were used. Shunt diameters and oxygen saturation levels increased from 2.05 ± 1.25 mm to 4.75 ± 0.88 mm and with 12 ± 6.8%, respectively. In 6 patients re-catheterizations were performed. Four patients died, all with patent shunts. The fail-stress and the fail-strain in the circumferential direction of the stretchable graft were significantly higher than in the non-stretchable graft. Conclusions Dilatation and stenting of stenosed modified systemic-to-PA shunts is feasible and safe. Dilatation and stenting of these shunts to calibers larger than those provided by the manufacturer is possible. Results of our technical study posit a great advantage for the use of the thin-walled stretch configuration of ePTFE.
Adaptive Support Ventilation: A Translational Study Evaluating the Size of Delivered Tidal Volumes
Authors: Veelo Denise P. , Dongelmans Dave A. , Binnekade Jan M. , Paulus Frederique , Schultz Marcus J. 
Published: March 2018

Purpose Adaptive support ventilation (ASV) is a microprocessor-controlled, closed-loop mode of mechanical ventilation that adapts respiratory rates and tidal volumes (VTs) based on the Otis least work of breathing formula. We studied calculated VTs in a computer simulation model, and VTs delivered in a test lung setting as well as in clinical practice. Materials and Methods In a computer simulation model using the Otis formula, VTs were calculated for increasing predicted body weights (from 50 to 80 kg) and increasing minute volumes (from 0.7 to 1.5 ml/kg). Different compliance-resistance combinations were chosen to mimic “acute lung injury (ALI)” (compliance 27 ml/cmH2O, resistance 20 cmH20 l/s), “ALI using an open lung approach” (compliance 50 ml/cmH2O, resistance 20 cmH20 l/s), “healthy lungs” (compliance 65 ml/cmH2O, resistance 20 cmH20 l/s) and “chronic obstructive pulmonary disease (COPD)” (compliance 80 ml/cmH2O, resistance 50 cmH2O l/s). In a test setting using a human ventilator connected to a test lung set to mimic similar pulmonary conditions, VTs delivered by the ASV were studied. In a series of stable intensive care unit patients after cardiothoracic surgery, the delivered VTs were collected and analyzed. Results VTs with the Otis formula resembled those in the test setting. With ALI, the ventilator delivered VTs between 6 and 8 ml/kg. With ALI using an open lung approach and with healthy lungs, the ventilator delivered VTs between 8 and 10 ml/kg. With COPD, all VTs were above 10 ml/kg. In patients after coronary artery bypass surgery ASV delivered VTs between 7 and 9 ml/kg and VTs never exceeded 10 ml/kg. Discussion The ASV performed as intended, bearing in mind that the ASV algorithm was originally designed to provide VTs between 8 and 12 ml/kg. However, the VTs that were calculated and delivered were frequently higher than those presently recommended in the guidelines. Considering the size of VT delivered in the setting of ALI using an open lung approach as well as in the setting of COPD, we feel caution should be taken when applying ASV in patients with these conditions.
Clinical Evaluation of Five Commercially Available Adult Oxygenators in Terms of Pressure Drop during Normothermic and Hypothermic Cardiopulmonary Bypass
Authors: Ji Bingyang , Wang Hongyue , Miao Na , Xing Jialin , Liu Wei , Liu Ruifang , Long Cun 
Published: March 2018

Background It is well documented that trans-membrane pressure drop (TMPD) of hollow-fiber membrane oxygenators (HFMO) may lead to hemolysis, damage to platelets, and systemic inflammatory response. The purpose of this study was to evaluate five commercially available adult oxygenators in terms of pressure drop during normothermic and hypothermic cardiopulmonary bypass (CPB). Materials and Methods In a clinical setting, 5 different adult HFMOs were tested in terms of TMPDs. Forty patients scheduled for cardiac surgery were enrolled in the study and were divided into 5 groups according to the type of oxygenator used during CPB: group J (Maquet Quardox n=8), group A (Affinity NT n=8), group P (Polystan Safe Maxi n=8), group T (Terumo Capiox SX 18 n=8) and group C (COBE APEX-TM n=8). Clinical parameters were collected during CPB, including mean arterial pressure (MAP), pump flow, temperature, hematocrit, duration of CPB, cross-clamp time and bypass time. TMPDs of pre-oxygenator and post-oxygenator pressures were recorded at the start of systemic cooling (T1), 10 min after stable hypothermia at 30°C (T2), and at termination of rewarming before the end of CPB (T3). Results There were no significant differences among the 5 groups in pump-flow rate, temperature, hematocrit, and mean arterial pressure during CPB. TMPDs of group J were the lowest at different time-points (T1, 30.71 ± 8.42mmHg; T2, 25.71 ± 5.41 mmHg; T3, 27.42 ± 13.01 mmHg). Compared to the other 3 groups (P, C and T groups), TMPDs of groups J and A at various time-points were lower (J group compared with the other three groups (p<0.001). Although TMPDs in groups A, P and T during hypothermia were higher than during normothermia and post-rewarming, there was no significant statistical difference (p> 0.05). Conclusions These results suggest that the HFMOs in groups J and A produced significantly lower TMPDs and pre- and post-oxygenator extracorporeal circuit pressures during normothermic and hypothermic CPB.
Mineral Water Administration may Increase Kidney Elimination of Urea, Creatinine and Folic Acid in a Concentration-Dependent Fashion
Authors: Calomino Francesco , Di Paolo Nicola , Nicolai Giulia , Miglio Antonio 
Published: March 2018

Background In a previous experimental study we showed that the administration of a large water load in a short time increases the urinary flow and the transport capacity in the excretory tract of the rabbit ureter. In human subjects drinking a water load of 25 ml/kgBW in 30 minutes, diuresis, creatinine and urea clearance increase more than in those drinking the same load in 24 hours. Purpose The aim of the present study was to investigate possible correlations between percent reduction and baseline values of serum urea, creatinine, folic acid, and magnesium in humans. Methods and results: 20 volunteers were divided in two groups. Subjects in group 1 received a water load of 25 ml/kgBW in 24 hours followed by the same load in 30 minutes. Subjects in group 2 received the same water load but in inverse order. Before and after each water administration, the following variables were measured and compared: diuresis, serum urea, creatinine, folic acid and magnesium concentration, and urea and creatinine clearance. Results Serum urea and folic acid concentration decreased up to 40% after administration of the water load in 24 hours. Serum creatinine concentration decreased up to 20% after administration of the water load in 30 minutes. The concentration drop of these metabolites increased with increasing baseline metabolite concentrations.
Feasibility of using Sodium Chloride as a Tracer for the Characterization of the Distribution of Matter in Complex Multi-Compartment 3D Bioreactors for Stem Cell Culture
Authors: Gerlach Jörg C. , Witaschek Tom , Strobel Catrin , Brayfeld Candace A. , Bornemann Reinhard , Catapano Gerardo , Zeilinger Katrin 
Published: March 2018

The experimental characterization of the distribution of matter in complex multi-compartment three-dimensional membrane bioreactors for human cell culture is complicated by tracer interactions with the membranes and other bioreactor constituents. This is due to the fact that membranes with a high specific surface area often feature a hydrophobic chemical backbone that may adsorb tracers often used to this purpose, such as proteins and dyes. Membrane selectivity, and its worsening caused by protein adsorption, may also hinder tracer transfer across neighboring compartments, thus preventing effective characterization of the distribution of matter in the whole bioreactor. Tracer experiments with sodium chloride (NaCl) may overcome some of these limitations and be effectively used to characterize the distribution of matter in complex 3D multi-compartments membrane bioreactors for stem cell culture. NaCl freely permeates most used membranes, it does not adsorb on uncharged membranes, and its concentration may be accurately measured in terms of solution conductivity. In this preliminary study, the feasibility of complex multi-compartment membrane bioreactors was investigated with a NaCl concentration pulse challenge to characterize how their distribution of matter changes when they are operated under different conditions. In particular, bioreactors consisting of three different membrane types stacked on top of one another to form a 3D network were characterized under different feed conditions.
A New Hemodialysis Monitoring Device Using Filtrate Concentrations: A Comparison with Standard Serum Techniques
Authors: Munaretto G. , Bonadonna A. , Piccoli A. , Sama C. 
Published: March 2018

A new device allowing sampling to be performed at any time, and using the filtrate obtained during hemodialysis is described. The device was used in 27 patients undergoing regular dialysis. Urea, creatinine and potassium were measured in samples taken both from arterial blood and from the device at 10, 40, 120 and 230 minutes after the beginning of the dialysis. The results were compared. A constant bias of about 10% was noted between the two sets of results but statistical analysis showed this was correctable.
Efficacy of Discontinuous Flow Centrifugation Compared with Cascade Filtration in Waldenstrom's Macroglobulinemia: A Pilot Study
Authors: Valbonesi M. , Montani F. , Guzzini F. , Angelini G. , Florio G. 
Published: March 2018

In the treatment of Waldenstrom's macroglobulinemia (WM) and lipoprotein or immune complex mediated diseases, centrifugal and membrane plasma separation systems have been successfully employed over the past years. More recently, semiselective double filtration systems have been used in isolated cases. While it is hoped that cascade filtration (CF) will soon become a routine technique, a note of caution came from some investigators because of the lack of any evidence that CF does really deplete patients' plasma of known pathogenic macromolecules. The aim of this study was to test the efficacy of CF in the removal of IgM paraproteins in comparison with discontinuous flow centrifugation (DFC). Eight patients were treated by DFC and seven by CF; there were no significant differences between the two groups in terms of sex, age, clinical severity and IgM plasma concentration. After DFC or CF sessions, IgM concentration diminished by 50% and plasma viscosity by 60%, producing a comparable mean reduction in patients' clinical severity. Our in vivo results thus preliminarily answer the question whether CF is capable of removing known pathogenic macromolecules from patiets' plasma, and the technique appears to warrant further investigations.
Comparative Analysis of Two Volumetrical Ultrafiltration Monitors for Hemodialysis
Authors: Berden J.H.M. , Wokke J.M.P. , Koene R.A.P. 
Published: March 2018

Controlled ultrafiltration (UF) during hemodialysis may prevent dialysis associated hypotension. A prerequisite for controlled ultrafiltration is an accurate measurement of ultrafiltration. Volumetric measurement is the best currently available method for this purpose. In this study we compared in a clinical setting two volumetric ultrafiltration monitors (UFM): one device constructed in our hospital using oval flowmeters (UFM-N) and the other using electromagnetic flow transducers (UFM-G: UFM 10-2, Gambro Lund Sweden). The UF measurements of both UFM's were compared with UF calculated from bedscales weight monitoring and standard scales determinations. During dual needle hemodialysis (n = 8) with a hollow fiber dialyzer the accuracy of the UFM-N was 91% and that of the UFM-G 97%. During dual needle dialysis with a parallel flow dialyzer the UFM-N appeared to be more sensitive for pulsatile changes in the dialysate flow due to the greater compliance of this type of dialyzer. The accuracy of the UFM-N in this setting was 80%, while that of the UFM-G was 87% (n = 11). During single needle dialysis with a parallel flow dialyzer (n = 14) only the UFM-G was tested and it measured UF with an accuracy of 92%. Finally the UFM-G can control UF actively by adjusting the TMP to obtain a given UF rate. The accuracy of the UFM-G in this setting was 94%, and the lineair regression correlation coefficient between planned UF and actually obtained UF was 0.974 (n - 61). In conclusion volumetric monitoring of UF is accurate and reliable, but its accuracy is dependent on the type of dialyzer used. The UFM-G proved to be useful in every dialysis modality tested, while the UFM-N can be used in dual-needle dialysis using hollow fiber dialyzers.
Plasma Exchange in Severe Erythema Nodosum Leprosum
Authors: Wallach D. , Bussel A. , Koch P. , Pennec J. , Cottenot F. 
Published: March 2018

Four patients with severe erythema nodosum leprosum were treated by plasma exchange and/or fresh frozen plasma infusions after failure of classical therapy. After the procedures, the patients improved rapidly; with a follow-up between 4 and 7 years after the last plasma exchange, no clinical relapse was noted. The replacement fluids were variable; the most beneficial procedure seemed to be plasma exchange replaced with fresh frozen plasma. Elimination of circulating immune complexes, replacement of a lacking plasma factor are possible mechanisms of action. Plasma exchange may also work like a regulator of immune mechanisms, since it has been shown that there is a depression of suppressor cells in erythema nodosum leprosum.