bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Hydroxy Ethyl Starch Infusion on Serum Bilirubin Levels in Cirrhotic Patients Treated with Artificial Liver Support
Authors: Kramer L. , Bauer E. , Gendo A. , Madl C. , Gangl A.
Published: January 2018

Serum bilirubin levels are commonly used to assess extracorporeal detoxification by liver support systems. We tested the hypothesis that intravenous colloids administered before liver support treatment could confound bilirubin values. Eight cirrhotic patients received an infusion of a 6% hydroxy ethyl starch solution (10 ml/kg, 30 minutes) before detoxification using a liver support system (FPSA). Bilirubin was measured before and 1 hour after infusion, and after FPSA treatment (7 hours). Infusion of hydroxy ethyl starch was associated with a drop in bilirubin values (mean, 18%, range, 1–44%, p=0.03 versus baseline values). Bilirubin levels were further reduced during FPSA treatment (mean, 27%, range, 22–34%; p=0.02 versus pre-treatment values). In conclusion, hydroxy ethyl starch solution may decrease bilirubin levels in hyperbilirubinemic cirrhotic patients receiving extracorporeal detoxification. The role of potentially confounding factors in liver support studies is discussed further.
Effects of Sorbent Suspension Dialysis on Plasma Amino Acid Levels in Cirrhotic Patients with Refractory Hepatic Encephalopathy
Authors: Bauer E. , Gendo A. , Madl C. , Garo F. , Roth E. , Kramer L.
Published: January 2018

In cirrhotic patients, plasma amino acid levels are severely deranged. A decreased ratio of branched-chain to aromatic amino acids (Fischer ratio) has been implicated in the pathogenesis of hepatic encephalopathy. In this prospective study, we investigated the effects of extracorporeal detoxification on amino acid levels using a sorbent suspension dialysis system. Twenty patients with documented cirrhosis and hepatic encephalopathy grade II-III not responding to standard treatment were randomized to receive either six hours of sorbent dialysis and standardized conventional medical treatment or ongoing medical treatment alone. In contrast to previous uncontrolled studies, no significant effect on amino acid levels, Fischer ratio or clinical grade of hepatic encephalopathy was detected in either treatment group. In conclusion, a 6-hour treatment with sorbent dialysis did not significantly influence plasma levels of amino acids and did not ameliorate the clinical grade of hepatic encephalopathy.
ALEX® (Artificial Liver for Extracorporeal Xenoassistance): A New Bioreactor Containing a Porcine Autologous Biomatrix as Hepatocyte Support. Preliminary Results in an ex Vivo Experimental Model
Authors: Ambrosino G. , Varotto S. , Basso S. , Galavotti D. , Cecchetto A. , Carraro P. , Naso A. , De Silvestro G. , Plebani M. , Giron G. , Abatangelo G. , Donato D. , Braga G.P. , Cestrone A. , Marrelli L. , Trombetta M. , Lorenzelli V. , Picardi A. , Valente M.L. , Palu G. , Colantoni A. , Van Thiel D. , Ricordi C. , D'amico D.F.
Published: January 2018

Long-term maintenance of viability and expression of differentiated hepatocyte function is crucial for bioartificial liver support. We developed a new bioreactor design (ALEX®), associated with a new extracellular autologous hepatocyte biomatrix (Porcine Autologous Biomatrix - PBM) support. To test this new bioreactor, we compared it to a standard BAL (Bio-Artificial Liver) cartridge in a ex vivo model using human plasma added to bilirubin, ammonium and lidocaine. A pathology study was performed on both bioreactors.

The results suggest that ALEX® allows a maximal contact between the perfusing plasma and the liver cells and a proper hepatocyte support by a cell-to-matrix attachment. ALEX® is a suitable cell support bioreactor, guaranteeing long-term maintenance of the metabolic activity of hepatocytes when compared to a standard BAL cartridge.
In Vitro Hydrodynamics of a Decellularized Pulmonary Porcine Valve, Compared with a Glutaraldehyde and Polyurethane Heart Valve
Authors: Dohmen P.M. , Scheckel M. , Stein-Konertz M. , Erdbruegger W. , Affeld K. , Konertz W.
Published: January 2018

Background:

Hydrodynamic performance of a decellularized pulmonary porcine valve was evaluated with a computer versatile pulse duplicator and compared to glutaraldehyde fixated stentless porcine bioprosthesis and a polyurethane heart valve.

Methods:

Decellularized pulmonary porcine matrices (Group I, n=5) were treated chemically to become cell-free collagen matrices. The findings of this heart valve were compared with aortic glutaraldehyde treated porcine prostheses (Group II, n=5) and polyurethane three leaflet valve prostheses (Group III, n=1). Measurements were performed in 0.9% saline test fluid at room temperature. Measurements compared were closing time, closing volume, systemic pressure difference and energy losses. Each valve was measured 6 times with 70 beats/minute, a stroke volume of 70 ml corresponds to a cardiac output of 4.9 L/minute.

Results:

Group I and group III showed no significant differences between parameters. The measured closing time was significantly different (p<0.001) between group I and II, respectively 24.333 and 53.600 ms and group II and III respectively 53.600 and 24.000. Difference in closing volume was significant (p<0.05) between groups II and I respectively 3.67 and 0.68 ms and group II and III respectively 3.67 and 0.71. Systolic mean pressure gradient was 18.25 ± 1.04 mm Hg in group II which was significantly different (p<0.001) from groups I and III, respectively 10.65 ± 0.29 mm Hg and 7.70 ± 0.30 mm Hg.

Conclusions:

Decellularized pulmonary porcine valves showed the same excellent performance as polyurethane valve prosthesis, which are superior to the investigated glutaraldehyde fixed xenograft.
Placement, Performance and Complications of the Ash Split Cath™ Hemodialysis Catheter
Authors: Gallieni M. , Conz P.A. , Rizzioli E. , Butti A. , Brancaccio D.
Published: January 2018

A tunneled catheter is the alternative vascular access for those patients in need of hemodialysis who cannot undergo dialysis through an arterio-venous fistula or a vascular graft.

This study was undertaken to evaluate the performance of the Ash Split Cath™, a 14 French chronic hemodialysis catheter with D-shaped lumens and a Dacron® cuff. After tunneling through a transcutaneous portion the catheter enters the venous system, where it splits into two separate limbs.

Data regarding catheter positioning, function and adequacy of dialysis were collected from two hemodialysis facilities. Twenty-eight Ash-split catheters were placed in 28 patients, with no complications, and immediate technical success was 100%.

Patients were followed up for a total of 7,286 catheter days. No catheter-related infections were observed. Only one catheter failed after 15 days, with a primary catheter patency of 96% for the whole study length. Mean blood flow was 303 ± 20 ml/min at 1 week after insertion, 306 ± 17 ml/min at 3 months, 299 ± 44 ml/min at 6 months, and 308 ± 16 ml/min at 12 months. With a mean dialysis session duration of 234 ± 25 minutes, adequate dialysis dose was observed for 96% of catheters, as reflected by a mean urea reduction ratio (URR) of 71%±8 or a mean urea kinetic modeling, or Kt/V, value of 1.51±0.3 during follow up. In conclusion, compared with previous studies we report the best permanent catheter performance, confirming that the Ash-split catheter is a good alternative for vascular access in hemodialysis patients who are not candidates for surgical A-V fistula or graft placement.
Intraindividual Comparison of two Extracorporeal LDL Apheresis Methods: Lipidfiltration and HELP
Authors: Julius U. , Metzler W. , Pietzsch J. , Faßbender T. , Klingel R.
Published: January 2018

Low density lipoprotein (LDL) apheresis is an effective treatment option for patients with severe hypercholesterolemia not adequately responding to diet and drug therapy. Membrane differential filtration (MDF), synonymous with double filtration plasmapheresis (DFPP), here named Lipidfiltration, and heparin-induced extracorporeal LDL-precipitation (HELP) are two of the five methods available for extracorporeal LDL apheresis.

In this prospective investigation 6 patients with severe LDL-hypercholesterolemia and CAD were treated in a cross-over design with Lipidfiltration at two stages of technical development and HELP to compare the efficacy of these two LDL apheresis methods with respect to lowering and modifying plasma lipids and rheologically relevant plasma proteins, especially fibrinogen. In total, 44 LDL apheresis sessions were investigated. In weekly intervals, patients were treated with consecutive LDL apheresis sessions with either Lipidfiltration and HELP, treating identical plasma volumes. In one part of the investigation Lipidfiltration was performed with the novel Lipidfilter EC-50, combined with a newly developed blood and plasma therapy machine allowing optimized plasma heating.

The results showed that the reduction rates of LDL-cholesterol, lipoprotein(a) and triglycerides were essentially identical for both methods. Also pretreatment levels of total cholesterol, triglycerides, LDL-cholesterol and HDL-cholesterol were not significantly different in both treatment groups. Both methods lead to a significant reduction of serum lipoproteins, especially for LDL-cholesterol, which was decreased by 61.4% with Lipidfiltration (treated plasma volume: 2998 ml) and 61.3% with HELP (treated plasma volume: 3013 ml). With respect to Lipidfiltration LDL-cholesterol reduction was more efficient with the novel Lipidfilter EC-50. Mean pretreatment HDL cholesterol concentrations remained unchanged. Comparing Cascadeflo AC-1770 with the novel Lipidfilter EC-50 reduction rates of HDL-cholesterol (17.4% versus 6.4%) and total protein (17.9% versus 7.8%) were significantly reduced. Lipidfiltration and HELP both resulted in a reduction of plasma viscosity and hemorheologically relevant plasma proteins, like fibrinogen.
Exploring the Damage Limitation Possibilities of Mineral Fibres for Future Integrated Solutions: An in Vitro Study
Authors: Gabbanelli F. , Mattioli-Belmonte M. , Giantomassi F. , Rimondini L. , Viticchi C. , Biagini G. , Torricelli P. , Gualtieri A.F. , Lesci I.G. , Giardino R.
Published: January 2018

Owing to their possible carcinogenic effect, asbestos and other silica derivatives have been identified as priority substances for risk reduction and prevention of pollution. Neutralisation procedures have thus become a topical research subject in many European and American countries. In the present study, silica derivatives (asbestos-containing and asbestos substitutes like slag wool, rock wool, cement asbestos) were fully impregnated with an epoxy resin according to the procedure used for the in situ impregnation with viscous polymeric media, which penetrate and cement the fibres in place and reduce the risk of their dispersion in air. Untreated and treated samples were used to investigate their in vitro interaction with a human continuous epithelial cell line (NCTC 2544 keratinocytes) and test the resin's efficiency in passivating the surface activity of the fibrous particulate. SEM and morpho-quantitative data evidenced that impregnation with the epoxy resin modifies the mineral fibres' bioactivity (reduction of cell adhesion and decreased spread/round cell ratio) and demonstrated the value of in vitro cell testing after passivation as a risk-assessment procedure. These tests could be used for the rapid determination of the level of passivation of new synthetic mineral fibrous materials subjected to resin impregnation.
Numerical Simulation of Carotid Hemodynamics in Patients with Rotary Blood Pump Cardiac Assist
Authors: Schima H. , Lackner B. , Prosi M. , Perktold K.
Published: January 2018

In recipients of rotary blood pumps for cardiac assist, the pulsatility of arterial flow is considerably diminished. This influences the shear stress patterns and streamlines in the arterial bed, with potential influence on washout and subsequent plaque growth. To study these effects, a three-dimensional computer simulation of the carotid bifurcation at various levels of flow pulsatility was performed. The results showed that as expected pulsatile shear stress varied considerably, whereas local mean shear stress levels were nearly identical for all degrees of pulsatility. Particle residence time in the carotid bulb did only increase for less than 15%, with secondary washout patterns contributing to good washout also in nonpulsatile conditions. It is concluded that also under continuous pump support the local flow patterns in the carotids provide sufficient washout and fluid exchange to prevent excessive plaque growth.
Acellular Scaffold Implantation – No Alternative to Tissue Engineering
Authors: Walles T. , Puschmann C. , Haverich A. , Mertsching H.
Published: January 2018

Objective

Degradation mechanisms of cardiovascular bioprostheses may play an important role in bioartificial implants. The fate of acellular implanted and cellular cardiovascular scaffolds was examined in an in vivo model.

Methods

Decellularized or native ovine carotid artery (CA, n=42) and aorta (AO, n=42) were implanted subcutaneously into rats for 2, 4 and 8 weeks. Immunohistochemical methods were used to monitor repopulation. Desmin-vimentin, CD31-, CD4- and CD18-antibodies for myocytes, endothelium, and inflammatory cell-infiltration, respectively. Calcification was detected by von-Kossa staining. Cell density was quantified by DNA-isolation.

Results

Acellular AO and CA matrices showed progressive calcification. Cellular AO and CA matrices trigger a strong inflammatory reaction which subsides after two weeks. CA scaffolds are revascularized progressively, whereas AO biocomposites degenerate. Calcification is less pronounced in cellular AO scaffolds and lacking in CA.

Conclusions

Acellular bioartificial implants demonstrate degradation mechanisms similar to currently applied cardiovascular bioprostheses. Cellularized viable implants are promising clinical alternatives.
Regeneration of Hypogastric Nerve Using a Polyglycolic Acid (PGA)-Collagen Nerve Conduit Filled with Collagen Sponge Proved Electrophysiologically in a Canine Model
Authors: Ito T. , Nakamura T. , Suzuki K. , Takagi T. , Toba T. , Hagiwara A. , Kihara K. , Miki T. , Yamagishi H. , Shimizu Y.
Published: January 2018

The hypogastric nerve (HGN) is a sympathetic nerve in the peritoneal cavity and controls urinary and seminal functions. In this study, the regeneration of HGN was determined by using a new type of an artificial nerve conduit, polyglycolic acid (PGA)-collagen nerve conduit filled with collagen sponge in two dogs. A PGA-collagen nerve conduit (diameter=2mm) was interposed in a 10 mm gap of the right HGN. The regeneration of the HGN was evaluated electrophysiologically 8 months after the operation. The intraluminal pressure of spermatic duct and the bladder neck were elevated 80 mmHg and 25 mmHg respectively by the stimulation across the regenerated HGN. The prostate contraction was also elicited. The responses diminished after the excision of the regenerated portion of HGN. These results proved the regeneration of HGN and this nerve conduit will be great help for patients who suffer from urinary and seminal disturbances.
Continuous Renal Replacement Therapy: Does Technique Influence Electrolyte and Bicarbonate Control?
Authors: Morimatsu H. , Uchino S. , Bellomo R. , Ronco C.
Published: January 2018

Background and objectives

Different techniques of continuous renal replacement therapy (CRRT) might have different effects on electrolyte and acid-base control. The aim of this study was to determine whether continuous veno-venous hemodiafiltration (CVVHDF) or continuous veno-venous hemofiltration (CVVH) achieve better control of serum sodium, potassium and bicarbonate concentrations.

Design

Retrospective controlled study.

Setting

Two tertiary intensive care units.

Patients

Critically ill patients with acute renal failure (ARF) treated with CVVHDF (n=49) or CVVH (n=50).

Interventions

Retrieval of daily morning sodium and potassium values and arterial bicarbonate levels from computerized biochemical records before and after the initiation of CRRT for up to 2 weeks of treatment. Statistical comparison of findings.

Measurements and results

Before treatment, abnormal (high or low) values were frequently observed for sodium (65.1% for CVVHDF vs. 80.0% for CVVH; NS), potassium (45.9% vs. 34.0%; NS), and bicarbonate (73.3% vs. 68.0%; NS). After treatment, however, CVVHDF was more likely to achieve serum sodium concentrations within the normal range (74.1% vs. 62.9%; p=0.0026). Both treatments decreased the mean serum potassium concentration over the first 48 h (p=0.0059 and p <0.0001, respectively), but there was no difference in terms of the normalization of serum potassium concentration during the entire treatment period (88.3% vs. 90.5%; NS). Both treatments increased the mean arterial bicarbonate concentration over the first 48 hours (p=0.011 and p <0.0001, respectively). However, CVVH was associated with a lower incidence of metabolic acidosis (13.8% for CVVH vs. 34.5% for CVVHDF; p <0.0001) and a higher incidence of metabolic alkalosis (38.9% vs. 1.1%; p <0.0001) during the entire treatment period.

Conclusions

CRRT strategies based on different techniques have a significantly different impact on sodium and bicarbonate control.
Role of Inflammation and Ischemia after Implantation of Xenogeneic Pulmonary Valve Conduits: Histological Evaluation after 6 to 12 Months in Sheep
Authors: Wilhelmi M.H. , Rebe P. , Leyh R. , Wilhelmi M. , Haverich A. , Mertsching H.
Published: January 2018

Objective

Commercially available biological heart valve prostheses undergo degenerative changes, which finally lead to complete destruction. Here we evaluate the role of inflammation and ischemia after implantation of xenogeneic heart valve conduits (XPC) generated by novel concepts of tissue engineering.

Methods

Acellularized (a-)XPC and autologus re-seeded (s-)XPC were implanted into sheep. Samples were taken as follows: after acellularization (n=2), after re-seeding (n=2), 6 months (seeded/non-seeded: n=3/5), 9 months (n=2/5), and 12 months (n=3/2) post implantation. Five native porcine conduits served as control. Using histological methods, samples were evaluated for pathological changes and existence/density of microvessels.

Results

Prior to implantation a-XPC were completely free of cells. Six months after implantation, leaflets and pulmonary arteries of s-XPC and a-XPC showed good endothelial surface coverage. Microvessel density within the myocardial cuffs and pulmonary vessel walls were comparable to control in all grafts. However, 6, 9 and 12 months after implantation pathological severe microvessel ingrowth, calcification and cellular infiltrations were observed on a-XPC and s-XPC valves, whereas myocardial cuffs and XPC-artery walls showed only mild degenerative alterations.

Conclusions

Inflammatory reactions play a pivotal role in the degeneration of a-XPC and s-XPC. Thus, since ischemia seems to have little or no influence on this process, inflammation inductive factors should be the center of interest.
Long-Term Therapy with Paricalcitol for Secondary Hyperparathyroidism in Hemodialysis Patients
Authors: Pai A. Barton , Lin S. , Arruda J.A.L. , Lau A. H.
Published: January 2018

Purpose

The efficacy of the vitamin D analog paricalcitol has mainly been shown in short-term studies. There are limited data regarding long-term treatment with this agent. This purpose of this study was to determine long-term effects of paricalcitol therapy on parathyroid hormone (PTH) suppression and serum levels of calcium, phosphorus and calcium-phosphorus product (Ca × P).

Patients and Methods

Patients who received paricalcitol for ≥ 3 months had the following data collected: demographics, drug dosage, serum PTH, corrected serum calcium concentration, serum phosphorus concentrations and serum Ca × P values.

Results

Sixteen patients received paricalcitol for a mean of 18 months. The mean ± SD dose of paricalcitol was 0.13 ± 0.12 mcg/kg. The mean ± SD pre-paricalcitol serum PTH concentration was 705 ± 423 pg/mL. PTH concentration did not change significantly over the duration of treatment (mean ± SD: 821 ± 480 pg/mL). The number of patients who had at least one corrected serum calcium concentration ≥ 11.5 mg/dL, one serum phosphorus concentration ≥ 6.5 mg/dL, or one Ca × P level ≥ 70 were 75%, 94% and 82%, respectively. Hypercalcemia and elevated Ca × P value resulted in a mean of 17% of doses being withheld during therapy.

Conclusion

During the study, PTH was not adequately suppressed by paricalcitol. This was primarily attributed to withholding paricalcitol doses due to elevated serum calcium and Ca × P levels.
Retinoic Acid Maintains Differentiated Cell Morphology and Functions in Long-term Cultured Porcine Hepatocytes: Obtaining Functional Cells for Prolonged Treatments with Bioartificial Liver
Authors: Bertagnolo V. , Puviani A.C. , Brogli M. , Carini C. , Brugnoli F. , Colamussi M.L. , Bellini G. , Morsiani E. , Capitani S.
Published: January 2018

Porcine hepatocytes show several immunological characteristics and enzymatic activities of human liver, representing an ideal xenogenic source of cells as biological component of bioartificial liver (BAL). Isolated hepatocytes rapidly lose their specific metabolic activities and their typical morphology when cultured in the presence of serum. Since in BAL porcine hepatocytes are perfused by the patient's plasma, procedures able to minimize de-differentiation of cells could be useful for long-term treatment of acute liver failure (ALF).

In this work we found that, in the presence of micromolar concentration of All trans-retinoic acid (ATRA), porcine parenchymal liver cells undergo to a lower extent the de-differentiating effects of long-term culture in the presence of serum. The evaluation of lidocaine metabolism showed that ATRA-treated cells retain specific hepatocyte function for a significantly longer time when compared to control hepatocytes. A tyrosine phosphorylation of PLC-γ1 was observed in concomitance with the ATRA-induced maximal functional activity. An increased expression of PLC-ß3 and PKC-α and -ß2 was also evidentiated at the longer time points explored, when the effects of ATRA in preservation of the differentiated morphology were maximal.

These results provide the first evidence that ATRA plays a differentiating role in adult porcine hepatocytes cultured under de-differentiating conditions. The administration of ATRA to isolated parenchymal cells from pig liver may provide functional hepatocytes for prolonged treatment with BAL.
In Vitro Behaviour of Osteoblasts Cultured on Orthopaedic Biomaterials with Different Surface Roughness, Uncoated and Fluorohydroxyapatite-Coated, Relative to the in Vivo Osteointegration Rate
Authors: Fini M. , Giardino R. , Borsari V. , Torricelli P. , Rimondini L. , Giavaresi G. , Aldini N. Nicoli
Published: January 2018

The effects of two surfaces with different roughness (Low Roughness, LR: Ra: 5.6–5.9 μm; High Roughness, HR: Ra: 21.5–22.5 μm), uncoated and fluorohydroxyapatite(FHA)-coated, were investigated in MG-63 osteoblasts. At 72 hours, cells proliferated on biomaterials more slowly than in the control group (p < 0.0001), the proliferation rate was higher on FHA-coated LR than uncoated HR (p = 0.037). Collagen-I production was positively affected by the LR surface (p = 0.001) as compared to controls, while it was significantly lower (p = 0.0001) in the HR surfaces. Compared to controls, LR and HR surfaces led to enhanced production of TGF-β1, further improved by FHA (FHA-coated LR: p = 0.007; FHA-coated HR p < 0.0001 respectively). ALP, OC, IL-6 and TNF-α levels were not significantly different from the controls. Results suggest that collagen-I production could be useful in predicting the in vivo osteointegration rate of biocompatible biomaterials observed in previous studies.
Changes in Serum Electrolytes during Treatment of Patients in Liver Failure with Molecular Adsorbent Recirculating System
Authors: Doria C. , Doyle H.R. , Mandalà L. , Marino I.R. , Caruana G. , Gruttadauria S. , Lauro A. , Magnone M. , Foglieni C. Scotti , Lamonaca V. , Scott V.L.
Published: January 2018

Purpose

To study the effect of MARS on serum electrolytes during liver failure.

Design

Twenty-three patients admitted to a quaternary health care facility from September 2000 to May 2002, 22 adults and 1 child, 11 males (48%) and 12 females (52%), age 15–70 (median 53), treated with MARS for: 12 acute-on-chronic liver failure (52%); 4 fulminant hepatic failure (17%); 3 intractable pruritus (13%); 2 primary-non-function (9%); 2 following major liver resection (9%).

Procedures

Sodium, potassium, chloride, phosphorus, calcium, and magnesium were measured in the serum, ultrafiltrate and albumin circuit before and after MARS.

Statistical methods

A comparison of electrolyte concentrations, before and after MARS, was performed using a paired t test.

Main findings

Serum electrolyte concentrations before and after MARS, while statistically significant in some cases, were very small, and of no clinical relevance.

Conclusion

MARS exchanges potassium, chloride, calcium, and magnesium by ultrafiltration; sodium by the albumin dialysis.
Enhanced in Vitro Maturation of Subcultivated Fetal Human Hepatocytes in Three Dimensional Culture using Poly-L-Lactic Acid Scaffolds in the Presence of Oncostatin M
Authors: Hanada S. , Kayano H. , Jiang J. , Kojima N. , Miyajima A. , Sakoda A. , Sakai Y.
Published: January 2018

Fetal human liver cell fractions, which contain large numbers of hepatocyte progenitors, have high proliferation potential in vitro. To create an engineered liver tissue equivalent of a clinically significant size, however, repeated subcultivation and functional maturation are necessary in vitro. A commercially available human fetal liver cell fraction that was cultivated for some time in vitro has been reported to lose liver specific functions almost completely. We therefore investigated the effects of oncostatin M (OSM) and hepatocyte growth factor (HGF) in long term three-dimensional (3D) culture using macroporous poly-L-lactic acid (PLLA) scaffolds on the restoration of such liver-specific functions of the fraction.

3D culture using PLLA scaffolds with OSM remarkably enhanced the albumin production and cytochrome P450 1A1/2 capacity with the culture time. HGF alone had no preferable effect on these functions even in 3D culture. α-fetoprotein production was consistently suppressed in the 3D culture compared with that in monolayers. This suppression was not observed in the same types of culture of hepatocarcinoma Hep G2 cells.

Despite these favorable observations on the 3D culture with OSM, the final attained functional levels at the 5th week were still over ten-times lower than those of Hep G2 cells when standardized with a cellular DNA amount. Although further improvement is needed for the complete functional restoration and maturation in vitro, these results demonstrate that a combination of 3D culture using PLLA scaffolds and OSM offers promising culture conditions for in vitro maturation of human hepatocyte progenitors.
Biomaterials in Orthopedic Surgery: Effects of a Nickel-Reduced Stainless Steel on in Vitro Proliferation and Activation of Human Osteoblasts
Authors: Torricelli P. , Fini M. , Borsari V. , Lenger H. , Bernauer J. , Tschon M. , Bonazzi V. , Giardino R.
Published: January 2018

A new austenitic stainless steel compound, P558, has been widely recognized to have good mechanical properties, excellent potential for corrosion resistance and negligible nickel ion release, making it a promising substitute for more expensive metallic prostheses with limited machinable features.

The effect of P558 was studied in vitro and human osteoblast- like cells (MG63) were cultured directly on P558, Ti6Al4V alloy (Ti), and polystyrene (Control) for 72 hours. Osteoblast functions were evaluated by assaying cell proliferation and synthetic activity after 1.25(OH)2D3 stimulation. Results demonstrated that growth of MG63 on P558 was not negatively affected when compared to the Ti and Control groups and showed no alteration in the production of ALP, NO and PICP. Moreover, IL-6 was lower, whereas OC and TGFß1 were significantly higher. SEM images revealed that cells proliferated and differentiated on P558 without any alteration in their morphology.

The current findings have demonstrated that P558 promotes osteoblast proliferation, activation and differentiation without negative effects and, thus, its good biocompatibility when used for orthopedic application.
Chronic Hemodialysis in a Nigerian Teaching Hospital: Practice and Costs
Authors: Agaba E.I. , Lopez A. , Ma I. , Martinez R. , Tzamaloukas R.A. , Vanderjagt D.J. , Glew R.H. , Tzamaloukas A.H.
Published: January 2018

The incidence of end-stage renal disease (ESRD) is on the rise in developing countries. To identify issues related to renal replacement therapy in ESRD patients in the developing world, we analyzed the practice and costs of hemodialysis in Nigerian ESRD patients. Ten ESRD patients were dialyzed at the Jos University Teaching Hospital, Jos, Plateau State, Nigeria, between June 15 and July 15, 2003. In these patients, we analyzed initiation, vascular access issues, frequency, duration, adequacy and economics of chronic hemodialysis. The Nigerian patients were referred to the nephrologist for the first time only when they had developed frank uremia. No patient had a permanent vascular access at the time dialysis was initiated. Only two patients had a functioning dialysis fistula, while the other eight patients were dialyzed through temporary femoral vein catheters that were removed after each dialysis. Frequency of dialysis was three times weekly in 2 patients, twice weekly in 1 patient and once weekly or less frequently in 7 patients. The duration of a dialysis session was prescribed to be 4 hours, but sessions often lasted for as long as 10 hours because of breakdowns of the antiquated dialysis machines. The urea reduction ratio was 45.3±8.6%. In every case, the cost of dialysis was borne by the patients and their families. Comparison of the cost of dialysis, with extensive re-use of supplies, to monthly incomes of Nigerians with different professions revealed that the great majority of Nigerians cannot afford three times weekly dialysis. Underdialysis in Nigerian ESRD patients is common and caused by socioeconomic factors and technologic deficits. One step towards correction of underdialysis could be sharing of the cost of dialysis by the public.
Elimination of Microbubbles from the Extracorporeal Circuit: Dynamic Bubble Trap versus Arterial Filter
Authors: Martens S. , Dietrich M. , Pietrzyk R. , Graubitz K. , Keller H. , Moritz A.
Published: January 2018

Background

Open heart surgery is associated with important risk of cerebral and peripheral organ dysfunction, attributed in part to microbubbles generated in or not eliminated from the ECC. For elimination of microbubbles, a dynamic bubble trap (DBT(tm)) was developed for the arterial line of ECCs.

Methods

Bubble eliminating properties of an arterial filter were evaluated in four CABG patients and compared to the performance of the DBT in four patients. One patient received both devices.

Results

Elimination of bubbles between 40–120μm was significantly higher with the DBT (88% vs. 57% with arterial filter, p=0.034). Reduction of bubbles below 40μm was equivalent in both groups. The combination of both devices was most effective (94% for bubbles >40μm).

Conclusion

Arterial filter and DBT are equally effective in elimination of smaller gas bubbles. However, bigger bubbles possibly causing cerebral and peripheral organ damage are eliminated to a greater degree by the DBT.
Aortic Valve Replacement and Perioperative Management in Hemodialyzed Patient wth Antiphospholipid Syndrome
Authors: Lango R. , Pawlaczyk R. , Raszeja-Specht A. , Smoleński R.T. , Rogowski J. , Rutkowski B. , Szutowicz A.
Published: January 2018

Antiphospholipid syndrome is characterized by the presence of antiphospholipid antibodies, hypercoagulability, and prolonged phospholipid-dependent coagulation indices such as activated clotting time (ACT). Perioperative thrombotic complications are frequent among patients with antiphospholipid syndrome submitted to cardiac surgery, therefore, in these patients, heparin-protamine titration for anticoagulation monitoring is particularly recommended. We demonstrate a case of 42-year-old hemodialyzed patient with antiphospholipid syndrome, submitted to the replacement of stenotic aortic valve. In our patient celite ACT and heparin concentration during cardiopulmonary bypass did not correspond to each other. Anticoagulation based on heparin concentration assessment resulted in safe perioperative hemostatic management.
Pregnancy-Associated Plasma Protein a during Hemodialysis with Polyamide and Diacetate Cellulosic Membranes
Authors: Kalousov¡ M. , Lachmanov¡ J. , Mokrejšov¡ M. , Míkov¡ B. , Fialov¡ L. , Malbohan I.M. , Tesař V. , Zima T.
Published: January 2018

Pregnancy-associated plasma protein A (PAPP-A) is a new prognostic factor of acute coronary syndrome in the general population. It is elevated in hemodialysis (HD) patients and at baseline, it was shown to be related to inflammation and oxidative stress. The aim of the study was to examine the relationship of PAPP-A and oxidative stress and inflammatory markers to HD treatment. Studied parameters were determined in 10 chronic HD patients treated with low flux polyamide (1st session) and diacetate cellulosic membranes (2nd session) at the beginning, after 15 minutes and at the end of the dialysis session. TRACE method (Time Resolved Amplified Cryptate Emission) was used for PAPP-A assessment. Results were evaluated with ANOVA.

PAPP-A levels did not depend on the type of HD membrane but changed significantly with the time of the HD session. They increased significantly from the beginning of HD to 15 min and then decreased to the end of the HD session – p<0.05 15 min of HD vs start, p<0.01 end vs start, p<0.0001 end vs 15 min of HD for polyamide membrane and p=0.05 15 min of HD vs start, p<0.01 end vs start, p<0.0001 end vs 15 min of HD for diacetate cellulosic membrane. Changes in other parameters and differences between membranes were only minimal.

We can conclude that PAPP-A as a marker of cardiovascular damage shows significant changes during the HD session. Its initial increase might be ascribed to its release from complexes or storage. During dialysis, it might be destroyed or cleaved and removed as free fragments. Its levels both before and after the HD session are higher than in healthy subjects.
Epidemiology and Outcome in Renal Failure
Authors: Vincent J-L. , Bota D. PERES , De Backer D.
Published: January 2018

Acute renal failure (ARF) in the ICU patient usually occurs as part of a wider multiple organ dysfunction, and is associated with mortality rates of around 50%. Differences in definitions make comparing study populations difficult and moves are being made to improve uniformity, and to recognize that ARF is not a single event but a continuous process from mild renal dysfunction through to complete organ failure requiring renal replacement therapy. In this review we will discuss the epidemiology of ARF within the limitations imposed by comparing studies that use different definitions and focus on different patient populations.
Acute Renal Failure and Rhabdomyolysis
Authors: Polderman K.H.
Published: January 2018

The clinical syndrome of rhabdomyolysis is caused by injury of skeletal muscles, leading to the release of various intracellular muscle constituents. Rhabdomyolysis occurs frequently but is usually asymptomatic (i.e., lab abnormalities only). However, in more serious cases, severe electrolyte disorders and acute renal failure may occur, leading to life-threatening situations. Rhabdomyolysis can develop in any circumstances where energy demands in muscles exceed the available energy supplies; it accounts for between 2 and 5% of all cases of acute renal failure in the ICU. Frequent causes of severe rhabdomyolysis include crush injuries, prolonged immobilization, seizures, severe infections and drug toxicity. Factors contributing to the development of more severe clinical symptoms include hypovolemia, hyperthermia, electrolyte disorders and the presence of preexisting (congenital) muscle disorders. The diagnosis is established by elevation of serum muscle enzymes and muscle constituents such as creatinine phosphokinase and myoglobin. Preventive measures include maintenance of normal or high intravascular volume and administration of diuretics (loop diuretics rather than mannitol) once hypervolemia/euvolemia have been achieved. Some evidence suggests that early initiation of renal replacement therapy can help improve outcome. Administration of bicarbonate to induce urinary alkalosis can be considered, but it has not been proven to be effective.
Hemofiltration in Heart Failure
Authors: Marenzi G. , Agostoni P.
Published: January 2018

In patients with severe congestive heart failure (CHF), removal of edema by hemofiltration is associated with significant clinical and hemodynamic improvement, correction of hyponatremia, restoration of urine output and diuretic responsiveness, and with a striking fall in neurohormonal activation. Through these effects, hemofiltration is able to interrupt the progression of CHF toward refractoriness, and to revert the clinical condition of CHF patients to a lower functional class.

Fluid refilling from the overhydrated interstitium is the major compensatory mechanism in the prevention of hypovolemia during hemofiltration.

Hemofiltration can also be beneficial in patients who have only moderate cardiac insufficiency (NYHA classes II and III) and in whom over-hydration is restricted to the pulmonary district significantly contributing to limiting patients functional capacity. In this setting, hemofiltration, differently from diuretics, is able to remove the increased lung water content and to improve clinical condition, exercise capacity and lung function.
Two Spent Dialysate Samples are Sufficient for Hemodialysis Efficacy Assessment
Authors: Kovacic V. , Ljutic D.
Published: January 2018

Introduction

The measure of dialysis efficacy is expressed as Kt/V value (calculated from predialysis and postdialysis blood urea concentration). The aim of this study was to assess the possibility of direct calculation of Kt/V value from two spent dialysate samples by using the regular blood-based Kt/V calculation formula with dialysate samples used as surrogates for blood samples, and to detect the most appropriate couple of dialysate samples for Kt/V estimation.

Patients and Methods

Fifty-two single hemodialysis treatments in 34 anuric patients on chronic bicarbonate low-flux hemodialysis were observed. Kt/V values according to Daugirdas formula from two blood samples and from two dialysate samples were calculated.

Results

Kt/V values calculated according to Daugirdas 2nd generation formula from blood samples (Kt/Vsp Daugirdas) were in significant correlation with all Kt/V values obtained from two spent dialysate samples. The highest correlation coefficient (r = 0.74, p & 0.001) and the least standard error of mean of the differences were found between Kt/Vsp Daugirdas and value obtained with substitution of urea concentration from dialysate samples taken 60 minutes after dialysis start and at the end of the dialysis into Daugirdas 2nd generation formula (Kt/VDCD(60)-CD(e)), which can be expressed as a equation of linear regression y = 0.47 + 0.86x. The highest correlation coefficient (r = 0.74, p & 0.001) was found between Kt/Vsp Daugirdas values equilibrated according to Daugirdas rate formula, and Kt/VDCD(60)-CD(e) value, which can also be expressed as an equation of linear regression y = 0.43 + 0.73x.

Conclusion

The results of this study clearly show the sufficiency of only two spent dialysate samples for direct estimation of the Kt/V values, with no blood sample required.
Augmentation of Abdominal Organ Perfusion during Cardiopulmonary Bypass with a Novel Intra-aortic Pulsatile Catheter Pump
Authors: Gu Y.J. , De Kroon T.L. , Elstrodt J.M. , Van Oeveren W. , Boonstra P.W. , Rakhorst G.
Published: January 2018

Background

Current pulsatile pumps for cardiopulmonary bypass (CPB) are far from satisfactory because of the poor pulsatility. This study was undertaken to examine the efficiency of a novel pulsatile catheter pump on pulsatility and its effect on abdominal organ perfusion during CPB.

Methods

Twelve pigs weighing 89±11 kg were randomly divided into a pulsatile group (n=6) and a non-pulsatile group (n=6). All animals had a CPB for 120 min, aorta clamped for 60 min, temperature down to 32°C, and a perfusion flow of 60 ml/kg/min. In the pulsatile group, a 21 Fr intra-aortic pulsatile catheter, which was connected to a 40 mL membrane pump, was placed in the descending aorta and activated by a balloon pump driver during the first 90 minutes of CPB until aortic declamping. Hemodynamics, organ blood flow, body metabolism, and blood trauma were studied during experiments.

Results

Compared with the non-pulsatile group during CPB, the pulsatile group had a higher systolic blood pressure (P&0.01), higher mean arterial pressure (P&0.05), and higher blood flow to the superior mesenteric artery (P&0.05). The hemodynamic energy, indicated by the energy equivalent pressure (EEP) was higher in the gastrointestinal tract and kidney in the pulsatile group (P&0.01, P&0.01). Abdominal organ perfusion status, as indicated by SvO2 in the inferior vena cava, was higher in the pulsatile group (P&0.05) 30 min after cessation of CPB. Hemolysis indicated by release of free hemoglobin during CPB was similar in the two groups.

Conclusion

Applying the pulsatile catheter pump in the descending aorta is effective in supplying the pulsatile flow to the abdominal organs and results in improved abdominal organ perfusion during the ischemic phase of CPB.
Myofibroblastic Differentiation in Simple Peritoneal Sclerosis
Authors: Del Peso G. , Jiménez-Heffernan J.A. , Bajo M.A. , Hevia C. , Aguilera A. , Castro M.J. , Sánchez-Tomero J.A. , LÓPez-Cabrera M. , Selgas R.
Published: January 2018

Objective

To analyze the presence of myofibroblasts in a series of peritoneal dialysis (PD) patients with simple sclerosis and non-PD, uremic patients. Since there is a close correlation between active fibrosis and myofibroblastic differentiation we wanted to test if myofibroblasts are present in uremic, non-PD peritoneal samples. To determine if there are correlations between myofibroblastic presence and other functional and morphologic peritoneal parameters.

Methods

Biopsies were collected from three patient groups: 1) Normal control samples (n=15) of parietal and visceral peritoneum 2) non-PD uremic patients (n=16); and 3) uremic patients on PD (n=32). Peritoneal morphologic and functional parameters and immunohistochemical expression of α-smooth muscle actin was analyzed in each case. Vascular endothelial growth factor (VEGF), bcl-2 anti-apoptotic protein, and progesterone receptor was evaluated in a subset of cases.

Results

Myofibroblasts were present in 56.3% of the patients with PD-related simple sclerosis. In most cases they were distributed in the upper submesothelial area. None of the biopsies from normal controls and uremic, non-PD patients showed myofibroblasts. Within the group of PD patients, myofibroblasts showed no correlation with time on dialysis, urea/creatinine MTAC, episodes of peritonitis, submesothelial thickening, hyalinizing vasculopathy or mesothelial status. In a subset of PD patients VEGF expression was observed in submesothelial fibroblastic cells. No expression of progesterone receptor or bcl-2 was observed.

Conclusions

Myofibroblasts are a reliable and simple indicator of fibrosis since they appear in early stages of PD treatment and in patients with minor morphologic anomalies. They are not exclusive of patients with sclerosing peritonitis, ultrafiltration loss or long standing treatment. Their absence in non-PD, uremic patients suggest that uremia-related fibrosis takes place without a significant participation of myofibroblasts.
Management of Fluid Balance in CRRT: A Technical Approach
Authors: Ronco C. , Ricci Z. , Bellomo R. , Baldwin I. , Kellum J.
Published: January 2018

Background

The possibility of making fluid balance errors during continuous renal replacement therapy has been identified since the beginning of this modality of treatment. The advent of automated machines has partially overcome this problem. Nevertheless, there are conditions and operation modes in which the potential for fluid balance errors is still present.

Objective

To analyse fluid balance management in CRRT therapies across a range of currently marketed machine.

Methods

The tests were conducted in vitro, utilizing saline solution for the blood circuit and regular dialysate/reinfusate for the dialysate/reinfusion circuit. The methodology used was based on the voluntary creation of a fluid balance error by altering the correct flow in the circuit of the different machines. Subsequently, the time for alarm occurrence and the threshold value for fluid balance error was evaluated. The alarm was overridden and the overall fluid error allowed by the machine was evaluated. Each machine was tested in conditions of different dialysate/filtrate flow rates and in different simulated treatment modalities.

Results

Fluid balance errors can be easily avoided not only by a correct and careful adherence to the protocols of use of the current CRRT machines, but also by the compliance to prescriptions and programmed controls during therapy. Most importantly, if an alarm appears on the machine, one can try to override it without major problems; major problems may occur when multiple override commands are operated without identifying the problem and solving it adequately.

Conclusion

Machines seem to be designed with adequate safety features and accurate alarm systems. However, features and alarms can be manipulated by operators creating the opportunity for serious error. Physicians and nurses involved in prescription and delivery of CRRT should have precise protocols and defined procedures in relation to machine alarms to prevent major clinical problems.
Ex Vivo Evaluation of a New Extracorporeal Lung Assist Device: NovaLung® Membrane Oxygenator
Authors: Jegger D. , Revelly J.-P. , Horisberger J. , Mallabiabarrena I. , Seigneul I. , Jachertz M. , Von Segesser L.K.
Published: January 2018

When lung function is compromised, alternative devices need to be deployed in order to maintain blood oxygenation. A new device, NovaLung®, has been designed for acute lung failure. We went about evaluating its gas exchange capability.

Three calves (79.5±7.8 kg) were connected to the NovaLung® System with a priming volume of 240 mL, gas exchange surface area of 1.3 m2 and exhibiting a biologically coated surface. A standard battery of blood samples were taken before implantation and over a six hour period.

Hematocrit remained stable ranging from 27±4% (baseline) to 29±5% (6 hrs). Platelets were preserved ranging from 882±27.4 U/L (baseline) to 734±147 (6 hrs). LDH remained stable at 719±85 U/L (baseline) vs 686±190 U/L (6 hrs) and the pressure drop was maintained below 20 mmHg. Minimal hemolysis was observed. Oxygen transfer peaked at two hours acute extracorporeal lung support (ECLS) with a mean value of 130±50 ml/min.

In conclusion, the device is easy to use, provides adequate O2 and CO2 transfer for partial lung support in an acute setting. Shows minimal signs of hemolysis and platelets levels are maintained throughout the six hour ECLS period.