bluuebunny/crossref_metadata_2025 huggingface dataset:
The Aachen-Keratoprosthesis - A Flexible KPro that Permits Intraocular Pressure Measurement
Authors: Krug A. , Kompa S. , Schrage N.F.
Published: January 2018

Purpose

Postoperative glaucoma is one of the major complications observed in patients with keratoprostheses (KPro). The optical components of the majority of KPros are rigid and inflexible, which prevents indirect tonometry by common methods. This study confirms that the Aachen-KPro allows measurements of intraocular pressure (IOP) due to its flexible optical part with a modified Schiotz tonometer.

Methods

The Aachen-KPro was placed in a special chamber where pressure can be generated and monitored by a transducer. Measurements were taken by common ophthalmologic methods. The results were compared to the initial pressure values in the chamber.

Results

With the Goldmann tonometer, the Tono-Pen and the topography system (Technomed), no significant pressure changes could be observed. The results of the Schiotz tonometer were promising. It was slightly modified and standard curves with different weights could be obtained.

Conclusions

With a modified Schiotz tonometer, it is possible to detect elevated IOPs. Modifying this common instrument is inexpensive and can be easily performed. This advantage of the Aachen-KPro permits early management of postoperative high tension glaucoma.
Diffusive Permeability of Rabbit Peritoneum for Small Solutes in Vitro: Effect of Gentamicin and Insulin
Authors: Szary B. , Czyżewska K.
Published: January 2018

The purpose of the in vitro study was to compare the diffusive transport of creatinine, uric acid and glucose, directed from the interstitial (I) to the mesothelial (M) side of the peritoneum and in the opposite direction, before (15–60min) and after (75–120min) application of gentamicin and insulin. The experiments were undertaken on the rabbit parietal peritoneum in a modified Ussing chamber. A mathematical model was used to calculate a diffusive permeability coefficient P (in cm/s) and a diffusive mass transport coefficient KH (in mL/min). In the basic experimental series without drugs, the dynamics of peritoneal transport for examined solutes remained constant and there were no differences between transport directions (I→ M and M→ I). Mean values of P±SEM (KH±SEM) were 3.06±0.32 (321.1±33.5), 2.09±0.29 (219.2±30.7) and 2.73±0.47 (286.7±49.6) for creatinine, uric acid and glucose, respectively. The introduction of gentamicin decreased glucose transport directed from the mesothelial to the interstitial side of the membrane by about 12%. After insulin application we observed the increase of creatinine and glucose peritoneal transport rate. For creatinine, the above augmentation was by about 31% for I→ M and 83% for M→ I direction. In these conditions, the glucose transport directed from the interstitial to the mesothelial side of membrane increased by about 24%. Generally, in vitro gentamicin decreases, but insulin increases the diffusive permeability of the peritoneum for some small solutes. We suppose that these findings may be important for the efficiency of peritoneal dialysis.
The Role of Autologous Fibrin-Platelet Glue in Plastic Surgery: A Preliminary Report
Authors: Valbonesi M. , Giannini G. , Migliori F. , Dalla Costa R. , Galli A.
Published: January 2018

To promote wound healing, we used autologous fibrin-platelet glue in 14 patients with skin and soft tissue losses caused by recent trauma or chronic pathology. The level of improvement was scored, arbitrarily, from 0 to 4. Very favourable results (score 3–4) were seen in 11 out of 14 patients. The glue preparation is very easy, inexpensive and creates excellent and stable hemostasis. From a general point of view, we have confirmed the utility of fibrin-platelet glue in terms of reduced infections and length of hospital stay.
Approach to Vascular Access for Hemodialysis: Experiences from the Republic of Macedonia
Authors: Oncevski A. , Dejanov P. , Gerasimovska V. , Polenakovic M.H.
Published: January 2018

Eight thousand eight hundred and forty nine different vascular hemodialysis accesses were performed in the period from 1976 until 1999 at the Department of Nephrology, Skopje: 3,114 native arterial-venous fistula (AVF), 715 arterial-venous shunts (AVS), 4,964 temporary or permanent catheters (4,411/88.86% femoral, 410/8.26% subclavian, 143/2.88% jugular) and 56 PTFE vascular grafts. Femoral catheterization (4,312/86.86%) is the favoured solution if a temporary vascular dialysis access is taken into consideration. The most popular chronic dialysis angio-access in our country is native AVF (90.5% of 3,440 permanent dialytic vascular accesses). The tunneled subcutaneously positioned catheters as a permanent dialytic angio-access were present in 270 cases (7.9%): 99 in femoral veins (our original method), 123 in subclavian veins and 48 catheters in jugular veins. The synthetic vascular grafts-PTFE (polytetrafluoro-ethylene) represent only 1.6% of all dialysis angio-accesses. The number of preventive AVFs created in patients with preterminal end-stage renal disease eventually increased; from 14% in the eighties, 20.8% after 10 years and 31.50% in 1999. Most of the preventive AVFs are done in outpatients 71.8% in 1999. This year 44.4% of all chronic vascular access were created in the same way.

We prefer femoral catheters for both temporary and permanent access because our results show that femoral catheterization has a lower rate of early complications when compared to the subclavian catheterization group; the rate of late complications (thrombosis, stenosis, infections) is lower or the same; infections in femoral catheterizations are less frequent, compared to subclavian and jugular ones.

Our contributions in the field of vascular access surgery are the three original methods which are constantly used at the Department: 1. Combination of temporary (AVS) and permanent vascular access (AVF) using the same blood vessels, performed in one surgical act; 2. Tunneled femoral catheter as a permanent vascular access for hemodialysis (2 types: on the abdominal wall and on the infrainguinal region - thigh); 3. Reduction of hyper-flow in AVF without the operation of “banding”, with ligation of the artery before arteriovenous anastomosis.
Extracorporeal Treatment Strategy in Acute Renal Failure
Authors: Jörres A.
Published: January 2018

The mortality of acute renal failure remains high (around 50–70%) despite manifold improvements in terms of techniques and equipment for renal replacement therapies as well as patient monitoring and intensive care support. At present, it is not clear if the method chosen for renal replacement therapy, i.e. intermittent hemodialysis or continuous hemofiltration, might impact on the outcome of these patients. Whilst earlier retrospective studies suggested that CVVH might result in better survival and renal recovery in acute patients, recent prospective studies indicated that this may not be the case or, conversely, outcomes may be better with IHD. These studies were, however, not evenly randomised in terms of illness severity or were too small to produce conclusive results. In addition, a meta-analysis of 9 published prospective studies in 692 pts. indicated a similar mortality with CVVH vs. IHD. Some of the studies enrolled for this meta-analysis, however, suffered from methodological and/or randomisation problems, thus this important question remains to date unanswered. Typically, CVVH is chosen for treating patients with hemodynamic instability and volume overload. In such cases, however, CVVH should be performed with a filtrate volume of at least 35 ml/kg body weight per hour as this was shown to be associated with better survival as compared to smaller filtrate volumes. A second controversy exists to date whether the choice of the dialyzer membrane might be of relevance for the outcome of patients with acute renal failure. Earlier studies indicated that the use of biocompatible membranes in these patients may result in improved patient survival and renal recovery. More recently, however, similar studies could not confirm these results. Another meta-analysis of controlled prospective trials (671 patients in 7 separate studies) calculated a relative mortality risk of 1.01 for cuprophan vs. biocompatible membranes. Thus, the choice of the dialyzer membrane should be based on individual assessment rather than treatment bias.
Priorities in Renal Replacement Programs
Authors: Bonomini V.
Published: January 2018

The various alternative programs in renal replacement therapy have precise meritocratic ranking which unfortunately is still largely ideal today. New directions and scientific plans (bioartificial kidney, new immunomodulators, gene therapy) have to be followed to make today's ideal ranking become reality.
Sodium and body fluid homeostasis in profiling hemodialysis treatment
Authors: Stefanidis I. , Stiller S. , Ikonomov V. , Mann H.
Published: January 2018

Acute adverse side-effects of hemodialysis such as hypotension, muscle cramps, osmotic imbalance and thirst are induced by the interference with fluid and electrolyte balance occurring during treatment. Changes in osmolarity due to alterations of plasma sodium concentration during hemodialysis strongly influence fluid distribution between extracellular and intracellular fluid volume. Increased sodium dialysate concentration induces fluid shift from the intracellular to the extracellular compartment. This shift leads to a more efficient ultrafiltration by increasing plasma refilling volume but also to an increased thirst. Treatment of hypotension, cramps and nausea with hypertonic saline solution leads also to a considerable retention of sodium. Profiling hemodialysis consists in deliberately changing ultrafiltration and dialysate sodium in order to combine an efficient ultrafiltration with a balanced sodium handling and to prevent side-effects during treatment. Continuous measurement and control of blood volume seems to be the best method to prevent hypotensive episodes. Profiling of sodium should not be the cause of a positive sodium balance. The clinical benefits of sodium profiling to the patients have still to be proven.
Testing protein permeability of dialysis membranes using SDS-PAGE
Authors: Mann H. , Melzer H. , Al-Bashir A. , Xu X.Q. , Stiller S.
Published: January 2018

Background

Permeability of dialysis membranes for high molecular weight compounds should be similar to that of the glomerular membrane in order to remove uremic toxins like the human kidney does. In order to evaluate permeability of high-flux dialysis membranes SDS-PAGE is applied for examination of filtrate of dialysers during routine dialysis with different membranes.

Method

SDS-PAGE analysis is performed with silver staining method according to the modification of Melzer (5) and consecutive laser densitometry.

Results

The protein pattern of filtrate from dialysis membranes is similar to that of the glomerular membrane containing IgG, transferrin, albumin, alpha-1-microglobulin, retinol binding protein and beta-2-microglobulin. Comparing different membranes there are considerable differences depending on cut-off, charge and adsorption capacity of the particular membrane. In all membranes tested permeability of proteins decreases during one treatment session.

Conclusion

Protein permeability of high-flux dialysis membranes is similar to the gloemerular membrane but modified according to pore-size, surface charge, adsorption and time on dialysis. In contrast to the glomerular membrane in each of the investigated membranes protein permeability decreases during function.
Heparin-Coated versus Uncoated Palmaz-Schatz Stent in Native Coronary Circulation. A Randomized Study with Blind Angioscopic Assessment
Authors: Kedev S. , Guagliumi G. , Valsechi O. , Tespili M.
Published: January 2018

The increasing use of stenting to treat more complex lesions and highly thrombogenic situations still carries higher risk for subacute stent thrombosis. To assess new heparin-coated stents in a more stringent reality, 40 consecutive patients were randomized in 1:1 ratio to receive either heparin-coated (group 1, 25 stents) or uncoated Palmaz-Schatz stents (group 2, 32 stents). The two groups were similar in baseline clinical, pre-and post-procedural angiographic and angioscopic characteristics. High pressure stent deployment without intravascular ultrasound guidance was used. All pts received antiplatelet agents alone. We applied serial angioscopy (baseline and on 7th day) to evaluate thrombus formation and quantitative coronary angiography (QCA) to define late (6 months, n=39, 100% the eligible pts) neointimal regrowth. There was one subacute stent thrombosis with subsequent acute myocardial infarction and death in the uncoated group.

Conclusion

The implantation of heparin-coated stents in nonselected population is well tolerated and associated with no clinical or angioscopic evidence of new thrombus formation, resulting in favorable long-term clinical and angiographic outcome.
Minimized Weight Gain between Hemodialysis Contributes to a Reduced Risk of Death
Authors: Stegmayr B.G. , Brannstrom M. , Bucht S. , Dimeny E. , Ekspong A. , Granroth B. , Grontoft K.C. , Hadimeri H. , Holmberg B. , Ingman B. , Isaksson B. , Johansson G. , Lindberger K. , Lundberg L. , Lundstrom O. , Mikaelsson L. , Mortzell M. , Olausson E. , Persson B. , Svensson L. , Wikdahl A.M.
Published: January 2018

The risk of death is higher in dialysis patients compared to age matched healthy subjects, the main reason being cardiovascular. This prospective study investigated if the extent of ultrafiltration was of importance for the outcome.

Material and Methods

88 hemodialysis patients were included and followed prospectively. The outcome was registered in regard to death, acute myocardial infarction or coronary vascular intervention. The extent of ultrafiltration needed at dialysis was calculated as a mean during the observation period as were other variables. The mean extent of ultrafiltration was compared for patients who had survived without end-points (group 1, n = 53) versus those who reached any endpoint during the period (group 2, n = 35).

Results

In total, 40% of the patients reached end-point during the observation period. There was no difference at baseline between the groups in regard to age, prevalence of diabetes mellitus or history of previous cardiovascular disease, KT/V, residual renal function ultrafiltration need, C-reactive protein, s-albumin, cholesterol, LDL-cholesterol, HDL-cholesterol, appetite or wellbeing, while triglyceride was lower in group 2 (p = 0.035). The observation period for group 1 was at a mean 24.7 months (SD13.1) and for those in group 2 at a mean 13.8 (±11.7 months, p < 0.001). Patients representing group 1 at 24 and 30 months had less need of ultrafiltration than those in group 2. Thus, the need of ultrafiltration was about 27% lower at 24 months (for 29 persons in group 1: 3.63 ± 1.93 weight% versus 4.97 ± 1.70 weight% for 9 patients from group 2, p = 0.046) and 46% at 30 months (for 18 from group 1: 3.48 ± 1.95 versus 6.45 ± 1.55 for 3 from group 2, p = 0.030). C-reactive protein did not differ significantly between the groups during the period.

Conclusion

After a prolonged period of 24 months the extent of ultrafiltration need seems to be important for the outcome of the patients. Thereby those with higher need of ultrafiltration had worse prognosis. It seems important to motivate patients to reduce the extent of fluid intake between dialysis to prolong survival.
Double Kidney Transplantation: Initial Experience of the Bologna Transplant Center
Authors: Nardo B. , Pacilè V. , Bertelli R. , Beltempo P. , Montalti R. , Puviani L. , Neri F. , Mosconi G. , Scolari M.P. , Liviano D'Arcangelo G. , Stefoni S. , Faenza A.
Published: January 2018

Aim

Double-kidney transplantation is performed using organs from marginal donors with a histological score not suitable for single kidney transplantation. The aim of the study is to verify the results obtained with double-kidney transplantation in terms of graft and patient survival and complications.

Methods

Between September 2001 and September 2004, 16 double-kidney transplantations were performed in our center. The kidneys were all perfused with Celsior solution and the mean cold ischemia time was 17.6 ± 2.7 hours. In all cases a pre-transplant kidney biopsy was performed to evaluate the damage. Immunosuppression was tacrolimus based for all patients.

Results

Eight patients had good renal postoperative function while the other eight had acute tubular necrosis. Two of the patients who had severe acute tubular necrosis never recovered renal function. There was only one episode of acute rejection, while the incidence of urinary complications was 31.2%; there were two surgical revisions for intestinal perforation. The graft and recipient survival was 78.1% and 100% and 78.1% and 93.7% at 3 and 36 months.

Conclusions

Double-kidney transplantation is a safe way to face the organ shortage. Moreover the score used in this study is useful to determine whether a kidney should be refused or suitable for single or dual-kidney transplantation. The results of our initial experience are encouraging, but this series is too small in number to consent a conclusive statement.
Time Dependent Non-Newtonian Numerical Study of the Flow Field in a Realistic Model of Aortic Arch
Authors: Del Gaudio C. , Morbiducci U. , Grigioni M.
Published: January 2018

A three-dimensional time dependent numerical simulation was performed in a geometric model of aortic arch complete with a realistic aortic root and major branches originating from the arch, for a peak Reynolds number set at 2200 and Womersley number set at 20.4. The computational fluid dynamic analysis was aimed to provide spatial and temporal distribution of the shear stress all along the entire model together with the velocity patterns, related both to the non planar geometry of the aortic system here considered and to the pulsatility imposed on the numerical model to simulate physiologic conditions. A non-Newtonian evolving fluid was considered to account for the actual rheological nature of blood; a comparison on the incidence of wall shear stress, implementing a Newtonian fluid, was also made as reference.

The spatial shear stress pattern, within the cardiac cycle, was shown to have higher values in correspondence to the inner wall of the aortic arch and the sites where the major vessels originated from the arch itself. The velocity patterns, on transversal sections of the aorta, resulted in highly skewed morphology. The resulting complex fluid dynamics, established in the aortic arch and in its branches, can be related to the possible endothelium response to mechanical stimuli, induced by wall shear stress, in the promotion of inflammatory events.
Coronary Artery Calcification, Common Carotid Artery Intima-Media Thickness and Aortic Pulse Wave Velocity in Patients on Peritoneal Dialysis
Authors: StompóR T. , Rajzer M. , Pasowicz M. , KraśNiak A. , SuƗOwicz W. , Kawecka-Jaszcz K. , Tracz W. , Janda K. , Tabor B. , Kowalczyk-MichaƗEk M.E. , WÓJcik K. , Konieczynska M. , Klimeczek P. , Janusz-Grzybowska E.
Published: January 2018

An increasing body of evidence suggests that atherosclerosis in patients with uremia differs from that found in general population in terms of advancement and localization of vascular lesions. It has also been suggested that different non-invasive techniques of vascular system evaluation are designed to show different types of lesions (i.e. vascular calcification, stiffness or “classical” atherosclerosis). The aim of the study was to search for possible associations between results obtained with three different non-invasive methods of vascular system assessment in three different vascular sites in patients treated with peritoneal dialysis (PD).

61 patients (28 F, 33 M), mean age of 50.4 ± 13.6 years, on maintenance PD for a median period of 10 months (range 1–96 months) were included. Coronary artery disease (CAD) was present in 21 subjects. In all subjects coronary artery calcification score (CaSc) using multi-row spiral computed tomography (MSCT), aortic pulse wave velocity (AoPWV) and ultrasound-based common carotid artery intima-media thickness (CCA-IMT) were performed as methods for assessing coronary calcium burden, arterial stiffness and atherosclerosis, respectively.

Median value of CaSc equaled 11.5 Agatston units (range 0–5502.8 units). Median AoPWV was 10.4 m/s (range 7.56–18.1 m/s), and median CCA-IMT – 0.6 mm (range 0.3–1.0 mm). In 16 patients (26.2%) at least one plaque in at least one common carotid artery was found on ultrasound. CaSc correlated with AoPWV (R = 0.32, p < 0.01) and with CCA-IMT (R = 0.35, p < 0.005), whereas no association was found between AoPWV and CCA-IMT. AoPWV, but not CaSc nor IMT correlated with blood pressure. The values of CCA-IMT and AoPWV increased together with consecutive Agatston categories (with p < 0.001 for differences in AoPWV and p < 0.05 for CCA-IMT). Patients with at least one plaque found in at least one CCA and patients with CAD were characterized with significantly higher values of CaSc, IMT and PWV, when compared to plaque-free and CAD- negative subjects, respectively.

Association between CaSc and both IMT and PWV may suggest that the mechanism of three assessed vascular pathologies may be based, to some extent, on the process of pathologic calcium-phosphate deposition. Lack of correlation found between PWV and IMT may suggest that aortic stiffness and carotid atherosclerosis may partially differ in their pathologic background and/or are dissociated in time.
Antigen Clearing from Porcine Heart Valves with Preservation of Structural Integrity
Authors: Ueda Y. , Torrianni M.W. , Coppin C.M. , Iwai S. , Sawa Y. , Matsuda H.
Published: January 2018

Bioprostheses currently used for replacement of diseased cardiovascular tissue are preserved and partially protected from immune rejection through chemical fixation. However, after implantation, chemically preserved (fixed) material has limited durability and lacks the ability to revitalize through cellular ingrowth and remodeling. As an alternative to fixation, we aimed at thoroughly removing antigens from tissue, leaving an intact scaffold, suitable for integration and revitalization in the host. Extensive washing of porcine heart valves with a mixture of two detergents (SDS and Triton X-100) yielded an intact matrix devoid of cells and depleted of soluble proteins that was minimally immunogenic in rabbits. A detailed characterization of the biomechanics and durability of the tissue is under way. If the lack of immunogenicity is confirmed in primates, our results would suggest that a detergent-washed, unfixed porcine heart valve can be an attractive non-inflammatory scaffold for heart valve regeneration in humans.
Evaluation of PDTC for Removing Ni(II) from Human Serum Transferrin in Vitro
Authors: Hooshmand A. , Badiei A. , Fatemi S.J.
Published: January 2018

Pyrrolidine dithiocarbamate (PDTC) can be an oral chelator with pKa= 3.300±0.002. It behaves as a bidentate ligand at serum pH. The effect of pH on Ni2+-Tf indicated that the maximum adsorption was at pH=7.4. The effective Ni-PDTC binding constant was determined (logk=11.1±0.1) for the 1:2 Ni(PDTC)2 complex using UV-vis spectra. The isosbestic point at 298 indicated that the complexation reaction was done directly (without side reaction). Removal of Ni from transferrin (Tf) was investigated by reverse titration of PDTC at 25°C and pH=7.4 using UV-vis spectra. PDTC is able to remove 25% of Ni from human serum transferrin.
Surface and Hemocompatibility Studies of Bi-Soft Segment Polyurethane Membranes
Authors: Queiroz D.P. , Pinto I.M. , Besteiro M.C.F. , Silva A.F.M. , Gil M.H. , Guiomar A.J. , De Pinho M.N.
Published: January 2018

Cross-linked urethane/urea membranes with two soft segments were prepared by extending a poly(propylene oxide) based tri-isocyanate-terminated prepolymer (PUR) with polybutadiene diol (PBDO). The ratio of prepolymer and polybutadiene diol was varied to yield cross-linked membranes with different compositions, exhibiting different degrees of phase-separation of the PBDO segments in the bulk and of surface enrichment in PUR. In this work, surface energy and hemocompatibility aspects (hemolysis and thrombosis) of the PUR/PBDO membranes were evaluated. The results showed that the membrane surface energy increased with the PBDO content until 25% of PBDO, and decreased thereafter. The introduction of the second, more hydrophobic, soft segment (PBDO) in the PUR membranes turned hemolytic into non-hemolytic membranes and, for a blood-material contact time of 10 minutes, decreased the thrombogenicity significantly. The 10% PBDO membrane was the least thrombogenic and was also non-hemolytic. The hemolysis degree did not vary significantly with the PBDO content while, for blood-material contact times of 10 minutes, the thrombogenicity increased with an increase in PBDO content above 10%. Membrane thrombogenicity varied with the blood-material contact time. For blood contact times of 10 minutes, all membranes tested were less thrombogenic than glass.
Histomorphometric Analysis of Poly-L/D-Lactide 96/4 Sutures in the Gastrocnemius Tendon of Rabbits
Authors: Kangas J. , Pajala A. , Leppilahti J. , RyhäNen J. , LäNsman S. , TöRmäLä P. , Waris T. , Ashammakhi N.
Published: January 2018

Background

Common Achilles tendon ruptures are not usually fixed by bioabsorbable sutures due to limitations in their strength retention properties. Modern technology has made it possible to develop bioabsorbable sutures with prolonged strength retention.

Aims

To evaluate histologically tissue reactions of poly-L/D-lactide (PLDLA) sutures implanted in Achilles tendon of rabbits.

Material and Methods

Fifteen rabbits were evaluated at 2, 6 and 12 weeks postoperatively, with five rabbits in each follow-up group. PLDLA monofilament sutures were implanted into the medial gastrocnemius tendon. Polyglyconate monofilament sutures with similar diameter (Maxon® 4–0, Cyanamid of Great Britain Ltd., Gosport, UK) were implanted in the contralateral gastrocnemius tendon. The histology was studied in hard-resin embedded samples. The thickness of the formed fibrous tissue capsule was determined histomorphometrically.

Results

PLDLA led to formation of significantly thinner fibrous tissue capsule than Maxon® sutures of the same diameter. Median thickness (PLDLA vs. Maxon®) at two weeks was 5.26 vs. 13.22μm, at six weeks 11.66 vs. 80.97μm, and at 12 weeks 10.63 vs. 17.59μm (p<0.01).

Conclusions

During the 12 week follow-up period, PLDLA sutures implanted intratendineously formed thinner fibrous capsule than Maxon® sutures of the same diameter. The suture materials were not totally absorbed by 12 weeks.
Molecular Recognition Based Iron Removal from Human Plasma with Imprinted Membranes
Authors: Yavuz H. , Andaç M. , Uzun L. , Say R. , Denizli A.
Published: January 2018

The aim of this study is to prepare ion-imprinted poly(2-hydroxyethyl methacrylate) (HEMA) based membranes which can be used for the selective removal of Fe3+ ions from Fe3+-overdosed human plasma. N-methacryloyl-(L)-glutamic acid (MAGA) was chosen as the ioncomplexing monomer. In the first step, Fe3+ was complexed with MAGA and then, the Fe3+-imprinted poly(HEMA-MAGA) membranes were prepared by UV-initiated photo-polymerization of HEMA and MAGA-Fe3+ complex in the presence of an initiator (benzoyl peroxide). After that, the template (i.e., Fe3+ ions) was removed by using 0.1 M EDTA solution at room temperature. The specific surface area of the Fe3+-imprinted poly(HEMA-MAGA) membranes was found to be 49.2 m2/g and the swelling ratio was 92%. According to the elemental analysis results, the polymeric membranes contained 145.7 μmol MAGA/g polymer. The maximum adsorption capacity was 164.2 μmol Fe3+/g membrane. The relative selectivity coefficients of ion-imprinted membranes for Fe3+/Zn2+ and Fe3+/Cr3+ were 12.6 and 62.5 times greater than the non-imprinted matrix, respectively. The Fe3+-imprinted poly(HEMA-MAGA) membranes could be used many times without decreasing their Fe3+ adsorption capacities significantly.
Comparison of Inflammatory Response during on-pump and off-pump Coronary Artery Bypass Surgery
Authors: Rimmelé Thomas , Venkataraman Ramesh , Madden Nicholas J. , Elder Michele M. , Wei Lawrence M. , Pellegrini Ronald V. , Kellum John A.
Published: January 2018

Purpose

On-pump coronary artery bypass graft (CABG) surgery has been traditionally associated with a higher magnitude of inflammatory response than off-pump CABG. However, with the development of polymer-coated biocompatible extracorporeal circuits, we wanted to see if cardiopulmonary bypass still played an important role in triggering this inflammatory response.

Methods

In this prospective observational study, 33 patients undergoing CABG surgeries (25 on-pump and 8 off-pump patients) were studied. Serial plasma cytokine (TNF, IL-6, IL-10) and procalcitonin concentrations were measured at different time-points during and after the surgery. Demographic and baseline clinical data, intra-operative management details and post-operative complications were also collected from the patients' charts.

Results

Plasma levels of all 4 mediators increased during surgery and returned towards normal post-operatively. There were no differences between groups for any mediator at any time-point.

Conclusions

We conclude that with the use of recent polymer-coated biocompatible extracorporeal circuits, the inflammatory response triggered by on-pump CABG becomes very similar in magnitude and pattern to that triggered by off-pump CABG. Thus, the surgical procedure contributes to most of the inflammatory response, with the extra-corporeal circuit having minimal to no effect on this response.
Improved Management of Intradialytic Hypotension (IDH) using Vitamin E-bonded polysulfone Membrane Dialyzer
Authors: Matsumura Masaki , Sasaki Hisako , Sekizuka Kumiko , Sano Hiroyuki , Ogawa Kouji , Shimizu Chihiro , Yoshida Hiroaki , Kobayashi Satsuki , Koremoto Masahide , Aritomi Masaharu , Ueki Kazue
Published: January 2018

Background

Intradialytic hypotension (IDH) is a common clinical trait in hemodialysis (HD) which is caused by poor biocompatibility of the dialyzer membrane. Aiming to improve IDH, vitamin E-bonded polysulfone dialyzer (VPS-H) was evaluated in a pilot study.

Methods

Eight IDH patients on standard HD were switched from their conventional high-flux dialyzers to VPS-H, and intradialytic blood pressure (BP) was monitored regularly for 10 months.

Results

The results showed that hypotension of systolic BP (SBP), diastolic BP (DBP) and pulse pressure (PP) during the session were improved after changing the dialyzer. Notably, almost all the values recorded from 120 minutes into the session until the end of the treatment in the period between the second and tenth month after treatment were significantly different from the corresponding baseline values. Moreover, after 8 to 10 months, the SBP prior to a dialysis session was significantly reduced compared with baseline values. On the other hand, the pulse rate showed no difference throughout the study period.

Conclusions

This study provides early evidence of the beneficial role that vitamin E-bonded dialyzers may have in preventing IDH. Larger controlled trials are needed to confirm this original finding.
Construction of Ureteral Grafts by Seeding Urothelial Cells and Bone Marrow Mesenchymal Stem Cells into Polycaprolactone-Lecithin Electrospun Fibers
Authors: Shen Jie , Fu Xiaoling , Ou Lailiang , Zhang Min , Guan Yong , Wang Kai , Che Yongzhe , Kong Deling , Steinhoff Gustav , Li Wenzhong , Yu Yaoting , Ma Nan
Published: January 2018

The aim of the present study was to investigated the construction of polycaprolactone-lecithin (PCL-L) electrospun fibers as a novel scaffold material for a tissue-engineered ureter. The effect of bone marrow mesenchymal stem cells (BM-MSCs) on the neovascularization of the scaffolds and the viability of planted urothelial cells (UCs) on PCL-L were also studied. UCs were obtained from New Zealand rabbit bladders, cultured and then seeded onto the lumen of the tubular scaffolds before being subcutaneously transplanted into the space of nude mice. The cultured UCs showed vacuolar degeneration after 7 days of transplantation and they gradually degraded thereafter. To facilitate the regeneration of the tissue-engineered ureter and the survival of UCs in the implant, MSCs were seeded into the tubular grafts by rolling up the nanofibrous membrane, followed by the seeding of UCs. This facilitated the survival of the UCs, which formed several cellular layers after 30 days. The mean microvessel density was significantly increased in tissues seeded with MSCs. Cell-tracking experiments revealed that the transplanted MSCs did not integrate directly into capillaries for angiogenesis. Our results demonstrated that the PCL-L electrospun fibrous scaffold has a high potential for a tissue-engineered ureter, especially when seeded with BM-MSCs, which enhanced angiogenesis.
Improvement of gas Transfer by Hemosome
Authors: Kim Gi-Beum , Hong Chul-Un , Kim Jin-Shang , Kim Min-Ho , Kang Hyung-Sub
Published: January 2018

Intravascular oxidation is a respiratory assist method used to treat acute respiratory distress syndrome (ARDS). However, intravascular oxidation through higher gas exchange is needed for successful clinical applications. In this study, an attempt was made to improve the gas exchange of an intravascular lung assist device by decreasing the level of damage to the blood through the microen-capsulation of hemoglobin. The results showed that a hemosome 0.8 μm in diameter could be produced by microencapsulating the hemoglobin extracted from fresh bovine blood with the phospholipids extracted from egg yolk. The oxygen saturation curve of hemosome was S-shaped, which is similar to that found in normal blood, and the P50 was 24 mmHg. The oxygen saturation in the mixed solution of hemosome and blood at a 1:4 (v/v%) ratio was similar to that of normal blood. The gas exchange of the blood-hemosome mixed solution was more effective than whole blood. Therefore, the hemosome solution is expected to improve oxygen transfer.
Improvement of Cytokine Response and Survival Time by Bioartificial Kidney Therapy in Acute Uremic Pigs with Multi-Organ Dysfunction
Authors: Wang Hengjin , Zhang Miao , Wang Xiaoyun , Mao Huijuan , Ying Xumin , Zhu Wenbin , Sun Cheng , Jiang Chunming
Published: January 2018

Objective

To explore whether bioartificial kidney (BAK) ameliorates cytokine response and biochemical indices, and prolongs the survival time in acute uremic pigs with multiple organ dysfunction syndrome (MODS).

Methods

Hybridized pigs suffering from MODS and acute renal failure (ARF) were treated with BAK (Group A, n=6) or sham-BAK containing no cells (Group B, n=6), or received no treatment (Group C, n=5). Data on blood pressure, hepatic and renal function, IL-10, TNF-α, arterial blood gas, and survival time of all the pigs was recorded.

Results

Mean arterial pressure (MAP, mmHg) responded more rapidly and reached higher values in Group A (91.82±5.73) compared with Groups B and C at 24 hours (p<0.01). The peak level of serum IL-10 (pg/mL) in Group A (249.57±43.51) was significantly higher than in Groups B and C (132.06±17.53, 104.25±13.42, p<0.01). Serum TNF-α level (pg/mL) in Group A dropped gradually to 402.91±32.47 at 24 hours, and showed a significant discrepancy compared with those before treatment (537.16±38.45) and Group B (512.94±19.5, p<0.05). There was no difference in plasma endotoxin and serum IL-6 between pre-treatment and post-treatment in Groups A and B. BAK treatment, however, resulted in a significant decline in IL-6/IL-10 ratios. The average survival time (hours) in Group A (113.01±14.32) was significantly longer, prolonged by 35.93% and 63.90% compared to Groups B and C (p<0.01), respectively.

Conclusions

The addition of renal tubule cell therapy to hemofiltration in an acutely uremic animal model with MODS altered systemic cytokine balance, ameliorated MAP, and prolonged survival time.
Microcontact Printing of Fibronectin on a Biodegradable Polymeric Surface for Skeletal Muscle Cell Orientation
Authors: Altomare Lina , Riehle Mathis , Gadegaard Nikolaj , Tanzi Mariacristina , Farè Silvia
Published: January 2018

Background and Objectives

Micropatterning and microfabrication techniques have been widely used to control cell adhesion and proliferation along a preferential direction according to contact guidance theory. One of these techniques is microcontact printing, a soft lithographic technique based on the transfer of a “molecular ink” from an elastomeric stamp to a surface. This method allows the useful attachment of biomolecules in a few seconds on a variety of surfaces with sub-micrometer resolution and control, without modifying the biomolecule properties. The aim of this study is to develop an easy and versatile technique for in vitro production of arrays of skeletal muscle myofibers using microcontact printing technique on biodegradable substrata.

Methods

Microcontact printing of fibronectin stripes (10, 25, 50 μm in width) was performed onto biodegradable L-lactide/trimethylene carbonate copolymer (PLLA-TMC) films. C2C12, a murine myoblast cell line, was used for the production of parallel myofibers.

Results

This approach proved to be simple, reliable and effective in obtaining a stable pattern of fibronectin on the PLLA-TMC surface as observed by fluorescence microscopy. C2C12 cells were well aligned along the pattern 24 hours after seeding, especially on fibronectin stripes 10 and 25 μm in width. Seven days after confluence cells fused and formed aligned multinucleated cells expressing α-actinin.

Conclusions

Fibronectin patterning seems to be a useful method to induce cell alignment and to improve myotube formation. Further studies will be focused on the possibility of applying external stimuli to these structures to obtain healthy myotubes and to induce myofiber development.
Prolonged Hypoxemia and Acidemia in Anesthetized Pigs: A Model for Research on Extracorporeal Organ Support in an Intensive Care Setting
Authors: Russ Martin , Ott Sascha , Bedarf Janis R. , Haacke Nadine , Keckel Tobias , Unger Juliane K.
Published: January 2018

Purpose

Hypoxemia and acidemia (hypoxemia/acidemia) are serious complications in the critically ill and often occur in unstable patients exposed to extracorporeal organ support. Still, little is known about the biocompatibility interactions of hypoxemia/acidemia with extracorporeal circuits (ECC). Existing animal models often include the release of mediator cascades (sepsis-, lung injury models) or are based on small laboratory animals. We established a porcine model of hypoxemia/acidemia without an underlying disease and further challenged the situation with an extracorporeal circuit (ECC).

Methods

Hypoxemia/acidemia were induced (3.5 h) and maintained (3 h) in anesthetized pigs (40 kg) by a stepwise reduction in oxygenation, infusion of 0.4 mol·l−1 lactic and hydrochloric acid and by low tidal volume ventilation, targeting an PaO2 < 70 mmHg, SvO2 < 65%, pH ~ 7.2. Venovenous hemofiltration (CVVH) operated in recirculation mode without volume exchange was chosen to prove the suitability of the model for studies on ECCs under clinical conditions (ECC group, n=6). Another 6 animals underwent the same protocol except for the CVVH (reference group, n=6).

Results

The median PaO2 during hypoxemia/acidemia was 62 mmHg, the median SvO2 was 38%, and the median pH was 7.22. Hypoxemia/acidemia was successfully induced and maintained for 6.5 h in all pigs. CVVH could be performed for 3 h with blood flow rates up to 300 ml·min−1 and filtrate rates up to 60 ml·min−1.

Conclusions

Our model provides hypoxemia/acidemia with blood gas values comparable to critically ill adult patients for several hours, during which it is possible to perform CVVH. Thus, it enables research on the biocompatibility reactions of extracorporeal circuits under intensive care conditions.
YhgC protects Bacillus anthracis from oxidative stress
Authors: Kiran Madanahally D. , Bala Shashi , Hirshberg Miriam , Balaban Naomi
Published: January 2018

Bacillus anthracis can cause lethal inhalational anthrax and can be used as a bioweapon due to its ability to form spores and to survive under various environmental stress conditions. YhgC in bacilli are structural homologues of TRAP, a protein involved in stress response in staphylococci. To test the role of YhgC in B. anthracis, YhgC gene was deleted in B. anthracis strain Sterne and parent and mutant strains tested. Immunolocalization studies indicated that YhgC is clustered both on the cell surface and within the cytoplasm. Phenotypic analyses indicated that YhgC is an important factor for oxidative stress tolerance and for macrophage infection in vitro. Accordingly, transcriptomics studies indicated that yhgC has a profound effect on genes encoding for stress response regulatory proteins where it negatively regulates the expression of genes encoding for Class I and Class III stress response proteins belonging to the regulons hrcA (hrcA, grpE, dnaK, dnaJ, groEL and groES) and ctsR (ctsR, mcsA, mcsB, clpC/mecB, clpP1). Proteomics studies also indicated that YhgC positively regulates the expression of ClpP-2 and camelysin, which are proteins involved in adaptive responses and pathogenesis in various Gram-positive bacteria. Put together, these results suggest that YhgC is important for the survival of B. anthracis under oxidative stress conditions and thus inhibition of YhgC may compromise the ability of the bacteria to survive within the host.
Time-Dependent Effects of Rifampicin on Staphylococcal Biofilms
Authors: Gattringer Klaus-Bernhard , Suchomel Miranda , Eder Michaela , Lassnigg Andrea M. , Graninger Wolfgang , Presterl Elisabeth
Published: January 2018

Objective

To test the time-dependent effects of rifampicin on established biofilms of Staphylococcus epidermidis isolated from patients with cardiac implant infections and catheter-related bacteremia.

Methods

Biofilms were grown in microtiter plates for 24 hours, dyed and stained with crystal violet. The mean optical density (OD) was used for quantification. The OD ratio (ODr = OD of the treated biofilm/OD of the untreated biofilm) was used to measure changes in the thickness of the biofilms over the time. Biofilms were incubated with rifampicin (0.6 mg/mL) for 1, 5, 15, 30 and 60 minutes. Unstained biofilms were sonicated and plated on Columbia agar for time-kill curves.

Results

The incubation of the biofilms with rifampicin led to a significant reduction of the OD of the biofilms within 1 minute (ODr baseline: 1; ODr 1 min: 0.333 ± 0.131) (p<0.001). With regard to bacterial killing, rifampicin reduced the mean log count, but viable bacteria were still grown from biofilms in 13 out of 28 isolates despite MIC values < 0.01 mg/L.

Conclusions

In conclusion, our results confirm that rifampicin at a concentration of 1.2 mg/mL immediately reduces established biofilms formed by S. epidermidis although it is not bactericidal despite very low MICs at planktonic conditions.
Photodynamic Action of Tri-meso (N-methylpyridyl), meso (N-tetradecyl-pyridyl) Porphine on Staphylococcus Epidermidis Biofilms Grown on Ti6Al4V Alloy
Authors: Saino Enrica , Sbarra Maria S. , Arciola Carla Renata , Scavone Mariangela , Bloise Nora , Nikolov Peter , Ricchelli Fernanda , Visai Livia
Published: January 2018

Staphylococcus epidermidis is a leading cause of nosocomial infections, and its virulence is attributable to formation of biofilm, especially on implanted devices. Photodynamic treatment (PDT) has been actively investigated for the eradication of bacterial biofilm growing on dental plaques and oral implants. In this study, we used Tri-meso (N-methyl-pyridyl), meso (N-tetradecyl-pyridyl) porphine (C14) for inactivation of two structurally distinct S. epidermidis biofilms grown on Ti6Al4V alloy and compared its photosensitizing efficiency with that of the parent molecule, tetra-substituted N-methylpyridyl-porphine (C1). A more significant reduction in bacterial survival was observed when both bacterial biofilms were exposed to a lower dose of C14, and simultaneously to visible light in comparison with C1. The different responses of both staphylococcal biofilms to C1- or C14-treatment appeared to depend on photosensitizer endocellular concentration. C14 bound to both biofilms to a greater extent than C1. Moreover, C14 penetrates deeper into the bacterial membranes, as determined by fluorescence quenching experiments with methylviologen, allowing for better bacterial killing photoefficiency. Confocal laser scanning microscope (CLSM) analysis indicated damage to bacterial cell membranes in both photodynamically treated biofilms, while disruption of PDT-treated biofilm was confirmed by scanning electron microscopy (SEM). In summary, C14 may be a potential photosensitizer for the inactivation of staphylococcal biofilms for many device-related infections which are accessible to visible light.
Antimicrobial Activity of Sodium Hypochlorite-Based Irrigating Solutions
Authors: Poggio Claudio , Arciola Carla Renata , Dagna Alberto , Chiesa Marco , Sforza Dario , Visai Livia
Published: January 2018

Purpose

The objective of the present study was the in vitro evaluation of the antimicrobial activity of three different NaOCl-based endodontic irrigating solutions: a 5.25% conventional sodium hypochlorite solution; and two new irrigating solutions, a 5.25% sodium hypochlorite solution with the addition of a proteolytic enzyme and a surfactant; and a 5.25% sodium hypochlorite gel with inorganic silicate.

Methods

Enterococcus faecalis, Staphylococcus aureus and Streptococcus mutans strains were selected to evaluate the antimicrobial activity of the endodontic irrigating solutions by the agar disc diffusion test. Paper disks were saturated with each one of the tested solutions (at room temperature and pre-warmed at 45°C) and placed onto culture agar-plates pre-adsorbed with bacterial cells and further incubated for 24 h at 37°C. The growth inhibition zones around each irrigating solution were recorded and compared for each bacterial strain.

Results

The results were significantly different among the tested irrigating solutions: 5.25% sodium hypochlorite solution produced the highest inhibition areas; 5.25% sodium hypochlorite solution with a proteolytic enzyme and a surfactant, and 5.25% sodium hypochlorite gel with inorganic silicate showed the lowest zones of inhibition.

Conclusions

Even if all tested irrigating solution possessed antibacterial activity versus all tested bacterial strains, 5.25% sodium hypochlorite solution with a proteolytic enzyme and a surfactant, and 5.25% sodium hypochlorite gel with inorganic silicate showed lower in vitro efficacy than 5.25% conventional sodium hypochlorite solution.