bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clearance of Levofloxacin by an in Vitro Model of Continuous Venovenous Hemodialysis (CVVHD)
Authors: Siewert S. , Drewelow B. , Mueller S.C. 
Published: January 2018

Information about the elimination and the adequate dosing of levofloxacin during renal replacement therapy is scarce. The aim of this study was to characterize in vitro the elimination of levofloxacin during continuous venovenous hemodialysis (CVVHD) and to investigate whether the CVVHD clearances of creatinine and urea are correlated with the levofloxacin clearance in order to facilitate dosage adjustments. An in vitro model of CVVHD was established using five dialyzer membranes at varying dialysate flow rates applied in the clinical setting (8, 16, 25, 33 and 41 ml/min). Plasma and dialysate samples were drawn for determination of levofloxacin, creatinine and urea concentrations to evaluate clearances by CVVHD. During CVVHD, the clearance of levofloxacin varied between 9.02 and 33.30 ml/min, depending on the chosen setup. Positive correlations (p<0.001) were received for: dialysate flow rate (QD) and creatinine/urea clearances (R>0.93); QD and levofloxacin clearance (R 0.59–0.71); levofloxacin and creatinine clearance (R 0.69–0.75); and levofloxacin and urea clearance (R 0.56–0.75) as well. When dosing critically ill patients, therefore, extracorporeal as well as total clearance of levofloxacin should be considered.
Integration of Blood Volume, Blood Pressure, Heart Rate and Bioimpedance Monitoring for the Achievement of Optimal Dry Body Weight during Chronic Hemodialysis
Authors: Bonello M. , House A.A. , Cruz D. , Asuman Y. , Andrikos E. , Petras D. , Strazzabosco M. , Ronco F. , Brendolan A. , Crepaldi C. , Nalesso F. , Ronco C. 
Published: January 2018

Background Achieving optimal dry body weight in hemodialysis is challenging. Clinical assessment alone is inadequate, and methods such as bioimpedance monitoring may be impractical for every patient treatment. Continuous blood volume monitoring, blood pressure and heart rate variability inform clinical decision-making, but integrated use of multiple methodologies to achieve dry weight and understand patient factors has not yet been described. Methods Nineteen chronic hemodialysis patients underwent thrice-weekly treatments for two weeks. Baseline hydration status and target weight were determined by bioimpedance. During subsequent treatments, ultrafiltration was adjusted and relative blood volume, blood pressure and pulse were recorded non-invasively Bioimpedance was repeated to assess hydration. Response of variables to progressive change in weight was assessed and selected patients underwent additional autonomic function testing. Results Four distinct hemodynamic patterns emerged. Profile A: 4 patients demonstrated overhydration at baseline. With decreasing target, pulse and blood pressure remained stable while blood volume and bioimpedance demonstrated achievement of dry weight. Profile B: 8 patients demonstrated overhydration at baseline. With decreasing target, blood pressure remained stable while pulse increased. Profile C: 5 patients were overhydrated, but as weight decreased, blood pressure became unstable and heart rate failed to compensate. Further testing confirmed autonomic dysfunction. Profile D: 2 patients were dehydrated, and with increasing target demonstrated stable pulse and pressure, while blood volume and bioimpedance revealed achievement of dry weight. Conclusions Integrating existing non-invasive, continuous monitoring during hemodialysis enabled achievement of dry weight and identified distinct profiles of the patients, some with autonomic dysfunction. This strategy may contribute to achieving optimum dry weight while improving cardiovascular tolerability of hemodialysis.
Uterine Myometrium as a Cell Patch as an Alternative Graft for Transplantation to Infarcted Cardiac Myocardium: A Preliminary Study
Authors: Taheri S.A. , Yeh J. , Batt R.E. , Fang Y. , Ashraf H. , Heffner R. , Nemes B. , Naughton J. 
Published: January 2018

Purpose Currently, only a small fraction of patients are able to receive reperfusion therapy for myocardial infarctions. We hypothesize that myometrial cell patch transplantation could be an alternative approach for the treatment of myocardial infarction. Design We performed a preliminary study to determine the feasibility of this novel therapeutic approach in a rabbit model. Procedures Six adult female New Zealand rabbits were used. Myocardial infarction was induced by left anterior descending artery ligation. A segment of uterus was removed via a laparotomy incision, and this uterine segment was transplanted as an autologous graft over the infarcted myocardium, which was then reinforced by greater omentum. Statistical methods and outcome measures Hemodynamic measurements and histological studies. Main findings: All uterine myometrial patches survived in the test animals. Fluoroscopic hemodynamic measurements were made for ejection fractions at 8 weeks after the application of the uterine patch. Histological study demonstrated well-healed myometrial-myocardium junctions with minimum scar tissue. Angiogenesis occurred in the transplanted myometrium. Connexin 43 expression was demonstrated in the transplanted patches. Conclusion Our noncontrolled preliminary rabbit experiments indicate that patches of uterine myometrium reinforced by greater omentum can be used as autologous transplant therapy for infracted myocardium. This is an innovative technique that could lead to future treatment for individuals who may suffer from an infarcted myocardium and may not be eligible for traditional reperfusion therapy.
Neurophysiological Assessment of the Electrostimulation Procedures Used in Stroke Patients during Rehabilitation
Authors: Lisiński P. , Huber J. , Samborski W. , Witkowska A. 
Published: January 2018

The aim of this study was to evaluate the effectiveness of the associated electrotherapeutical and kinesiotherapeutical treatment in patients after ischemic stroke (N=24), mainly by means of neurophysiological tests. All patients underwent the same 20 days of neurorehabilitation procedures. Particular attention was paid to three-stage modified electrotherapy procedures such as: oververtebral functional electrical stimulation (FES), transcutaneous electrical nerve stimulation (TENS) and the alternate neuromuscular functional electrical stimulation (NMFES) of antagonistic muscles of the wrist and the ankle (N=16). Electrotherapy was supplemented with kinesiotherapeutic (mainly PNF) procedures acting as an amplifier. Clinical assessment included muscle tension (Ashworth's scale), muscle force (Lovett's scale) and reflex scoring at wrist and ankle. However, the effectiveness of the procedures was measured by the assessment of results in complex and repetitive, bilaterally performed global electromyography (EMG) and electroneurography (ENG; M-wave studies). The statistical analysis obtained from results in clinical and neurophysiological examinations suggested that the dorsiflexion of wrist and ankle was improved in the majority of patients who took part in this study. EMG and ENG examinations showed that 20 days of therapy improved both activity in muscle motor units on the more paralyzed side (mainly within upper extremities) and to a lesser degree in the transmission of efferent impulses within motor fibers of nerves. The results obtained suggest that patients after ischemic strokes never show an isolated unilateral disability in motor functions. No definite similarities between the results of clinical and neurophysiological studies were found, which may suggest greater accuracy of the neurophysiological evaluation.
Residual of Bacterial Dna in Hemodialyzers: The Proof of Subclinical Infection Sustaining Chronic Inflammation
Authors: De Cal M. , Cazzavillan S. , Rassu M. , Ronco C. 
Published: January 2018

Background and purpose Inflammation and infection seem to be important causes of morbidity and mortality in Chronic Kidney Disease (CKD) patients. Subclinical infections have been proposed as an important cause of inflammatory syndrome but to date this hypothesis remains speculative. In this investigation, we developed a method for molecular detection of the presence of bacterial DNA in a population of chronic kidney disease patients in order to correlate molecular data with the degree and level of inflammation and to evaluate the usefulness of the method in the diagnosis of subclinical infection. Design The study was divided into two phases: the study of a population of 81 CKD patients for prevalence and level of inflammation and infection; and the molecular evaluation of a subgroup of 38 patients without evident clinical causes of inflammation for molecular evaluation of subclinical infection. Results Patients hemoculture negative turned out positive for the presence of bacterial DNA when molecular methods were used. We found a trend of correlation with the presence of bacterial DNA and the increase in hs-CRP, IL-6 and oxidative stress (AOPP) levels and a reduction in MFI DR+. Hemodialyzer membranes seem to have properties that are “sticky” to bacteria/bacterial DNA and work as concentrators. Moreover our data suggest that DNA can traverse hemodialysis membranes. Conclusions Molecular methods have turned out to be far more sensitive than standard methods in detecting subclinical infection. The presence of bacterial DNA seems to influence the variation of some parameters of inflammation and immunity. Apart from the limitations and pitfalls, a molecular method could be useful for the screening of subclinical infection and diagnosis of sepsis when the hemoculture is negative. The identification of the microorganism involved, however, must be done with species-specific primers. These results are preliminary and more investigations will have to be performed in order to confirm our results.
Vascular Endothelial Growth Factor in Dialysate in Relation to Intensity of Peritoneal Inflammation
Authors: Pawlaczyk K. , Polubinska A. , Numata M. , Nakayama M. , Pecoits-Filho R. , Czekalski S. , Lindholm B. , Breborowicz A. 
Published: January 2018

Background Peritoneal inflammation may induce changes in peritoneal microvessels, including neoangiogenesis/vasculogenesis, leading to increased peritoneal solute transport rate (PSTR) and loss of ultrafiltration capacity. We hypothesized that an inflammatory reaction in the peritoneal cavity during peritonitis induces increased synthesis of vascular endothelial growth factor (VEGF). We therefore studied the relationship between peritoneal inflammation markers, VEGF, and transport of fluid and solutes in rats during acute peritoneal inflammation induced by lipopolysaccharide (LPS) added to standard glucose-based dialysis solution. Methods Under ether anesthesia, male Wistar rats were injected intraperitoneally with 30 mL Dianeal 3.86% without (Control; n=6) or with LPS (μg/mL): 0.001 (LPS 0.001; n=6), 0.01 (LPS 0.01; n=7), 0.1 (LPS 0.1; n=7), 1.0 (LPS 1.0; n=8). After 8 hours, dialysate volume (IPV), peritoneal solute transport rate (PSTR) and dialysate cell count (DCC) were measured and effluent samples were collected. Results LPS i.p. resulted in increased PSTR and decreased IPV (p<0.005). DCC (cells/μL) and the neutrophil/macrophage ratio were higher for all LPS concentrations compared to the control group. After 8 hours, LPS-exposed rats had significantly higher dialysate levels of all investigated cytokines (TNF-α, MCP-1 and IL-10) than the control group. Addition of LPS resulted in increased dialysate VEGF concentrations (pg/mL) (LPS 0.001, 28.2±5.9; LPS 0.01, 38.9±11.6; LPS 0.1, 43.0±5.9; LPS 1.0, 46.6±11.3; Control, 14.5±9.8; p<0.0005 for all LPS vs. Control). Conclusions The infusion of Dianeal 3.86% with different doses of LPS induced a strong acute intraperitoneal inflammatory reaction with increased DCC and cytokine levels, resulting in increased peritoneal solute transport and decreased IPV LPS induced a dose-dependent parallel increase of the intraperitoneal concentrations of MCP-1, IL-10 and TNF-α, as well as of VEGF. These results suggest that intraperitoneal VEGF synthesis is induced in response to inflammation, and that this may be an important component in the process leading to peritoneal transport alterations.
Still Stuck in the Slime
Authors: Arciola C. R. 
Published: January 2018

The role of biofilm in implant infections and the genetic control of its production are still giving rise to great interest and controversial new results are continuing to emerge from widespread investigations. Bacteria embedded in biofilms are more resistant to most antibiotics. Hypotheses regarding the mechanisms of antibiotic multi-resistance in biofilm are brought to light, including the onset of persister cells during the attachment of bacteria to implant surfaces. This 2008 special issue “Focus on Implant Infections”, presents new strategies for combating biofilm infections, such as the use of staphylococcal quorum-sensing inhibitors or the “bioelectric effect”: the phenomenon by which electric current can enhance the activity of some antimicrobial agents against bacteria in biofilms. (Int J Artif Organs 2008; 31: 749–51)
The Extracellular Polymer Substance of Pseudomonas Aeruginosa: Too slippery for Neutrophils to Migrate On?
Authors: HÄnsch G. M. , Brenner-Weiss G. , Prior B. , Wagner C. , Obst U. 
Published: January 2018

Purpose Biofilm formation is increasingly recognized as the cause of persistent infections and there is evidence that P. aeruginosa organized into biofilms are quite resistant toward host defence mechanisms, particularly against an attack by polymorphonuclear neutrophils (PMN). Apparently, the migration of PMN through the biofilms is impaired, and thus the bactericidal activity remains highly localized. The aim of this study was to directly investigate the interaction of PMN with the biofilm and the extracted extracellular polymeric substance (EPS) of P. aeruginosa. Material and Methods Chemotaxis and random migration of PMN through P. aeruginosa biofilms was tested, as was their migration through and along the EPS. Results We found that the EPS and mature biofilms, but not immature or developing ones, reduced the chemotactic migration of PMN. On EPS, rather than immobilize the cells, their random, spontaneous migration was enhanced. Conclusion We propose that on EPS, the PMN lose their capacity to sense the direction and just slide over the EPS in a disoriented manner. (Int J Artif Organs 2008; 31: 796–803)
Effects of Coupled Plasma Filtration Adsorption on Immune Function of Patients with Multiple Organ Dysfunction Syndrome
Authors: Mao H.-J. , Yu S. , Yu X.-B. , Zhang B. , Zhang L. , Xu X.-R. , Wang X.-Y. , Xing C.-Y. 
Published: January 2018

Objective To investigate the effects of coupled plasma filtration adsorption (CPFA) on the immune function of patients with multiple organ dysfunction syndrome (MODS). Methods This study was a prospective, pilot, before-and-after self-crossover, clinical trial. Seven patients diagnosed with MODS and severe infection were randomly allocated to both 10 hours of CPFA and 10 hours of high-volume hemofiltration (HVHF) with a 12-hour interval and in random order. Serum concentrations of 7 cytokines including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), interleukin-10 (IL-10), interleukin-1 receptor antagonist (IL-1Ra), and soluble tumor necrosis factor receptors 1 and 2 (sTNFR1 and sTNFR2) were measured during each treatment. The HLA-DR expression by the blood monocytes and the TNF-α production by the patients’ blood (both spontaneous and lipopolysaccharide stimulated) were tested before and after the treatment. TNF-α production of normal human monocytes (THP-1 cells) incubated in vitro with the patient plasma was also measured. Results During CPFA, the fall in serum TNF-α and rise in serum IL-1Ra coincided with the rise in ratios of sTNFR2/TNF-α and IL-1Ra/IL-1β (p<0.05), which were different from those seen within HVHF (p<0.05). HLA-DR expression increased after CPFA (84.32% ± 4.63% vs. 73.65% ± 11.52%, p=0.037), but there was no change after HVHF (p>0.05). Spontaneous and lipopolysaccharide-induced TNF-α production increased over time with CPFA (p=0.038, p=0.034, respectively), but did not change with HVHF (p>0.05). Patient plasma suppressed the production of TNF-α by cultured normal monocytes. This effect decreased over time with CPFA (p=0.041), but there was no effect with HVHF (p>0.05). Conclusions CPFA was superior to HVHF in increasing the ratios of antiinflammatory to proinflammatory mediators, improving antigen presentation ability, and restoring leukocyte responsiveness. These findings suggest a potential role for CPFA in the treatment of MODS.
Preventive Effect of α-Tocopherol and Glycyrrhizin against Platelet-Neutrophil Complex Formation Induced by Hemodialysis Membranes
Authors: Takeshita Kana , Susuki Chie , Itoh Saotomo , Tsuji Tsutomu 
Published: January 2018

Background The intradialytic activation of leukocytes is a major cause of hemodialysis (HD)-associated complications. Contact between blood and HD membranes frequently induces the formation of microaggregates composed of activated platelets and leukocytes, causing leukocyte activation that includes the generation of reactive oxygen species (ROS). This complex formation is mediated primarily by the interaction between P-selectin on activated platelets and its counter-ligands on leukocytes. Objective We examined the preventive effects of α-tocopherol and glycyrrhizin in vitro against platelet-neutrophil microaggregate formation and neutrophil ROS production induced by HD membranes. Methods and Results Microaggregate formation induced by the incubation of heparinized whole blood with polysulfone (PS) HD membranes was effectively inhibited by α-tocopherol and glycyrrhizin. α-Tocopherol, but not glycyrrhizin, was found to inhibit PS membrane-induced P-selectin expression on the platelet surface; however, glycyrrhizin did inhibit both the formation of neutrophil-platelet microaggregates induced by adenosine diphosphate (ADP) and the adhesion of HL60 leukemic cells to P-selectin-expressing Chinese hamster ovary (CHO) cells, suggesting that glycyrrhizin acts as a competitive inhibitor of P-selectin-mediated cell adhesion. Finally, these compounds almost completely abrogated PS membrane-induced and platelet-dependent ROS production by neutrophils. Conclusions These results suggest that α-tocopherol and glycyrrhizin may function as preventive agents of HD-associated leukocyte activation though the modulation of platelet-leukocyte interaction.
Dynamic Modeling and Identification of an Axial Flow Ventricular Assist Device
Authors: Moscato Francesco , Danieli Guido A. , Schima Heinrich 
Published: January 2018

An accurate characterization of the hemodynamic behavior of ventricular assist devices (VADs) is of paramount importance for proper modeling of the heart-pump interaction and the validation of control strategies. This paper describes an advanced test bench, which is able to generate complex hydraulic loads, and a procedure to characterize rotary blood pump performance in a pulsatile environment. Special focus was laid on model parameter identifiability in the frequency domain and the correlation between dynamic and steady-state models. Twelve combinations of different flow/head/speed signals, which covered the clinical VAD working conditions, were generated for the pump characterization. Root mean square error (RMSE) between predicted and measured flow was used to evaluate the VAD model. The found parameters were then validated with broadband random signals. In the experiments the optimization process always successfully converged. Even in the most demanding dynamic conditions the RMSE was 7.4 ml/sec and the absolute error never exceeded 24.9 ml/sec. Validity ranges for the identified VAD model were: flow 0–180 ml/sec; head 0–120 mmHg; speed 7.5–12.5 krpm. In conclusion, a universal test bench and a characterization procedure to describe the hydrodynamic properties of rotary blood pumps were established. For a particular pump, a reliable mathematical model was identified that correctly reproduced the relationship between instantaneous VAD flow, head and impeller speed.
Ovine Models for Chronic Heart Failure
Authors: Geens Jefh , Trenson Sander , Rega Filip R. , Verbeken Erik K. , Meyns Bart P. 
Published: January 2018

Purpose Testing and optimizing of surgical therapies for chronic heart failure (CHF) requires large animal models. CHF has been induced in several large animal species. Sheep have modest body mass increase and demonstrate docile behavior and are therefore a preferred species in research on surgical therapies for CHF. Methods A literature search for existing ovine CHF models was performed, using search terms “sheep” and “heart failure”. Relevant secondary references were traced. Results Rapid ventricular pacing produces rapid-onset CHF. Its severity ranges from moderate left ventricular failure to severe biventricular failure, depending on length and frequency of pacing. Its counterpart in human CHF is tachycardia-induced HF, since it is reversible upon cessation of pacing. Myocardial damage models include CHF induced by cardiototoxic drugs and ischemia. Ischemia-based models include coronary microembolization, occlusion and ischemia/reperfusion models. The microembolization model is relevant to diabetic cardiomyopathy. Coronary occlusion models exhibit variable functional impairment, some with aneurysm formation, and some with mitral valve regurgitation, depending on occlusion localization. They are relevant to CHF following non-reperfused myocardial infarction. Coronary occlusion/reperfusion models are relevant to the occurrence of human CHF despite coronary artery recanalization. Pressure overload of left and right ventricle is induced by aortic and pulmonary artery banding, respectively. Hypertrophy precedes CHF, as in patients with valve stenosis and hypertension. Volume overload is induced by valve damage or shunt creation. Atrioventricular valve regurgitation is the most important clinical counterpart. Conclusion Several ovine CHF models exist. Since they exhibit important cardiac pathology differences, the choice of model should be based on the specific experimental question.
Heterotypic Cell-Cell Interaction on Micropatterned Surfaces
Authors: Lamponi Stefania , Canio Clara Dl , Barbucci Rolando 
Published: January 2018

Purpose The aim of this paper was to study the influence of chemical and topographical signals on cell behavior and to obtain a heterotypic cell-cell interaction on microstructured domains. Methods The polysaccharide hyaluronic acid (Hyal) was photoimmobilized on glass surfaces in order to obtain a pattern with squares and rectangles of different dimensions and chemistry. The microstructured surfaces were characterized by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The behavior of Human Coronary Artery Endothelial Cells (HCAEC) and human tumoral dermal fibroblasts (C54) was investigated on these micropatterned surfaces by adhesion studies. Moreover, heterotypic interaction among C54 and HCAEC adherent on patterned surfaces was evaluated by time-lapse video microscopy. Results Surface analysis revealed the presence of a pattern consisting of alternating glass and Hyal microstructures whose dimensions decreased from the center to the edge of the sample. Neither HCAEC nor C54 adhered to the immobilized Hyal but both adapted their shape to the different sizes of the glass squares and rectangles. The number of adherent cells depended on the dimensions of both the glass domains and the nuclei of the cells. Co-cultured C54 on HCAEC patterned surfaces showed a heterotypic cell-cell interaction in the same chemical and topographic domain. Conclusions A heterotypic cell-cell interaction occurred in the same chemical and topographic micro-domains but in narrow areas only. Moreover, the number of cells adhering to the glass domains and cell morphology depended on the dimensions of both adhesive areas and cell nuclei.