Replacement Technique Research Articles

Comparison of Spatial Distributions of Intracluster Light and Dark Matter

In a galaxy cluster, the relative spatial distributions of dark matter, member galaxies, gas, and intracluster light (ICL) may connote their mutual interactions over the cluster’s evolution. However, it is a challenging problem to provide a quantitative measure for matching the shapes between two multidimensional scalar distributions. We present a novel methodology, named the weighted overlap coefficient (WOC), to quantify the similarity of two-dimensional spatial distributions. We compare the WOC with a standard method known as the modified Hausdorff distance (MHD) method. We find that our method is robust, and performs well even with the existence of multiple substructures. We apply our methodology to search for a visible component whose spatial distribution resembles that of dark matter. If such a component could be found to trace the dark-matter distribution with high fidelity for more relaxed galaxy clusters, then the similarity of the distributions could also be used as a dynamical stage estimator of the cluster. We apply the method to six galaxy clusters at different dynamical stages, simulated within a GRT simulation, which is an N-body simulation using the galaxy replacement technique. Among the various components (stellar particles, galaxies, ICL), the ICL+brightest cluster galaxy (BCG) component most faithfully traced the dark-matter distribution. Among the sample galaxy clusters, the relaxed clusters show stronger similarity in the spatial distribution of the dark matter and ICL+BCG than the dynamically young clusters, while the results of the MHD method show a weaker trend with the dynamical stages.

Bicuspid Aortic Valves: an Up-to-Date Review on Genetics, Natural History, and Management.

Bicuspid aortic valve (BAV) is the most common congenital cardiac abnormality. It has a wide spectrum of clinical manifestations including aortic regurgitation (AR), aortic stenosis, and an associated aortopathy with a small but increased risk of aortic dissection. This review describes current knowledge of BAV, from anatomy and genetics to a discussion of multifaceted strategies utilized in the management of this unique patient population. This review will also highlight critical knowledge gaps in areas of basic and clinical research to enhance further understanding of this clinical entity. The current knowledge regarding pathophysiologic mechanisms, screening, and surveillance guidelines for BAV and the associated aortopathy is discussed. We also discuss current management techniques for aortic valve repair versus replacement, indications for aortic surgery (root or ascending aorta), and the emergence of the Ross procedure as a viable management option not only in children, but also in adolescents and adults. The varied clinical phenotype of the BAV, resulting in its specific complex hemodynamic interactions, renders it an entity which is separate and distinct from the tricuspid aortic valve pathologies. While various aortic histopathologic and protein alterations in BAV patients have been described, it remains unclear if these changes are causal or the result of hemodynamic alterations imposed by sheer stress on the intrinsically dysfunctional BAV. Medical management for patients with BAV with AS, AI, or dilated aortic roots/ascending aortas remains challenging and needs further investigation. More than 50% of patients with BAV will undergo AVR during their lifetime, and more than 25% of patients with BAV undergo aortic surgery performed for dilation of the aortic root or ascending aorta, often concurrently with AVR. The search for the ultimate genetic or epigenetic cause of the different bicuspid phenotypes will ultimately be facilitated by the next-generation sequencing tools that allow for study of large populations at low cost. Improvements in diagnostic and stratification criteria to accurately risk assess BAV patients are critical to this process.

Novel technique of sutureless pulmonic valve replacement for quadricuspid pulmonic valve with huge pulmonary artery aneurysm.

Novel technique of sutureless pulmonic valve replacement for quadricuspid pulmonic valve with huge pulmonary artery aneurysm.

Partial replacement of broom sorghum panicle residue and tallow with whole cottonseed in growing-finishing diets for lambs

Sixty-four Pelibuey × Katahdin male lambs (14.3± 2.2 kg initial live weight) were used in an 84-d growing-finishing trial to evaluate optimal levels of inclusion of whole cottonseed (WCS) in a broom sorghum panicle residue-based diet. Dietary treatments consisted in partial replacement of broom sorghum panicle residue (SPR) and tallow with 0, 10, 20 or 30% WCS. Control diet contained 66.5% PSR and 3% tallow, and replacing were as follows: 10% of WCS replaced 9% SPR and 1% tallow (WCS10), 20% WCS replaced 18 SPR and 2% tallow (WCS20), and 30% WCS replaced 27% SPR and 3% tallow (WCS30). Inclusion of WCS increased (quadratic component, P=0.03) average daily gain (ADG), dry matter intake (DMI) and gain efficiency. However, with increasing level of WCS substitution the observed/expected dietary net energy ratio decreased (linear effect, P<0.01). The estimated NEm value for WCS determining by the replacement technique at the 10, 20 and 30% levels of inclusion were 2.48, 2.23, and 2.15 Mcal/kg, respectively. Consistent with the increased final weight, hot carcass weight and longissimus muscle area were increased (linear effect, P≤0.03) with increasing level of WCS inclusion. While, dressing percentage and fat thickness tended to increase (linear effect, P=0.10) with increasing WCS level. The partially replacement of broom sorghum panicle residue and tallow by up to 20% inclusion of WCS in finishing diets for lambs enhances ADG, gain efficiency, carcass weight, and LM area. However, the net energy value of WCS decreases with level of inclusion greater than 10%.

Proximal humerus fractures: anatomy, diagnosis and management.

Proximal humeral fractures are common with a bimodal distribution and sex discrepancy, affecting younger men and older women. The presentation of a proximal humeral fracture can vary greatly because of this bimodal distribution and the associated differences in mechanism of injury. Initial management should involve assessment of life- and limb-threatening injuries as outlined by the British Orthopaedic Association Standards for Trauma, with particular attention paid to axillary nerve function and vascular status. Initial imaging should involve orthogonal X-rays in three planes to determine fracture characteristics and exclude glenohumeral dislocation. Computed tomography imaging improves interobserver agreement and is the gold standard in determining fracture management. Management depends on fracture pattern, patient functionality and bone stock. Most patients with proximal humeral fractures achieve good functional outcomes via conservative methods (sling support and early, graded mobilisation), although there is a lack of evidence in certain populations, including younger patients. Surgery is required for open fractures and more complex fracture patterns where there is a risk of avascular necrosis of the humeral head, unacceptable impairment of functionality or neurovascular compromise. Surgical techniques can be head-sparing or involve replacement of the humeral head. There are several head-sparing techniques, each with different cost-benefit and complication profiles with no one technique superior to any other. However, improvements in plate technology may render open reduction internal fixation a more suitable technique, particularly in younger patients. Head replacement techniques (hemiarthroplasty and reverse shoulder arthroplasty) are indicated when the risk of avascular necrosis is too high or in older patients with osteoporotic bone. In these patients, reverse shoulder arthroplasty is preferred as it achieves better functional results than hemiarthroplasty. Complication rates vary depending on the fracture configuration and the course of management undertaken.

Technique for replacement of Groshong® peripherally inserted central venous catheters (PICCs) in children.

The use of peripherally inserted central catheters (PICCs) in children is increasingly common due to their certain advantages and low rate of adverse events. Valved PICCs, when displaced, must be removed and new a PICC must be placed in another vein. We present our PICC replacement technique over a Seldinger guidewire using the same entrance vein. This prospective study involved all consecutive patients with a previously inserted Groshong PICC (Bard Access Systems Inc., Salt Lake City, UT, USA) requiring replacement due to displacement managed at our institution between January 2018 and January 2019. All procedures were performed at the patients' bedside, under local anesthesia. All the steps of the procedure were described. The procedure was performed in 19 patients (mean 10.4 years, range 5-18 years) in a mean time of 12 minutes (range 10-35). In all cases, the maneuver was quick and painless. No complications were encountered during the procedure and at follow-up. Our preliminary experience suggests that the PICC replacement technique using the same entrance vein is simple, safe, and feasible, and provides clear benefits to preserve children's venous patrimony.

ANALISIS KESALAHAN BERBAHASA TATARAN SINTAKSIS PADA TEKS BERITA SISWA KELAS VIII SMPN 2 PANGENAN CIREBON TAHUN PELAJARAN 2021/2022

This research is a qualitative descriptive study with the subject of this research in the form of a document of the results of the VIII grade students of SMPN 2 Pangenan Cirebon. Data collection techniques used by researchers in this study are in the form of documentation techniques and note-taking techniques. Meanwhile, the validity checking technique used triangulation technique. The data analysis used in this study used the agih method and continued using the basic technique for direct elements or the BUL technique. After using the basic technique, it was continued using advanced techniques, namely by using the lesap technique, the replacement technique, the reverse technique, and the extension technique to facilitate data analysis. The results of this study are in the form of a description of the analysis of language errors at the syntactic level in the student news text. The results are 39 forms of phrase errors and 11 forms of sentence errors. With the results of the analysis of language errors at the syntactic level, educators should be able to obtain an overview of appropriate learning models, methods, and media to support the improvement of students' writing skills, especially in the field of syntax.. Keywords: Language Error, Syntax, News Text

An Analysis of Paraphrasing Techniques Used by Student at the Fifth Grade English Education Department of IAIN Bukittinggi Academic Year 2022/2023

This research was conducted based on the problem found in academic writing class about paraphrasing at English Education Department at the fifth semester IAIN Bukittinggi. Paraphrasing is known as a way to avoid plagiarism while creating scientific papers or journals. However, the researcher interviewed the lecturer and found that the most of the students have difficulty putting the ideas into their own words. They used too many words from the original passage that shows the students were lack of vocabulary mastery. Moreover, the students used monotonous technique of paraphrase. This research used mixed method. It is a procedure for collecting, analyzing, and mixing both quantitative and qualitative methods in a single study or a series to understand a research problem. The students were given a paraphrasing test to know the students ability. The data were analyzed using scoring rubric proposed by Callison. After that, some students were interviewed to find out the dominant paraphrasing technique used by the students. After calculating the score, the result of the study showed that the student’s ability in paraphrasing was 59. As writing band suggested by Leo, the students’ ability in paraphrasing is in moderate level where it is rather well organized. Arguments are rather relevant in relation to writer’s view. Main ideas and supporting ideas are rather clear. The message is almost clear but with some loss of detail. In addition, the interview showed that most of the students use synonym replacement technique in paraphrasing the text. It is because most of the student agreed that the technique is the easiest technique to use.

An analysis of complication rates and the influence on patient satisfaction and cosmetic outcomes following oncoplastic breast surgery

This study aimed to evaluate complication rates, patient satisfaction, and cosmetic outcomes after oncoplastic breast-conserving surgery (OPS). Furthermore, outcome differences between volume displacement and volume replacement techniques and the effect of postoperative complications on outcomes were evaluated. This was a prospective single-center study addressing patients who underwent OPS from 2017 to 2020. The BREAST-Q was used to measure patient satisfaction, and cosmetic outcomes were assessed by patient self-evaluation and panel evaluation based on medical photographs. A total of 75 patients were included. The overall complication rate was 18.7%, of which 4% required invasive interventions. Median BREAST-Q scores ranged from 56 to 100 and cosmetic outcomes were scored good to excellent in 60-86%. No differences in complications were observed between volume replacement and volume displacement techniques. Following volume displacement techniques, patients-reported higher BREAST-Q scores for the domain "physical well-being of the chest" and lower cosmetic outcomes scores for "mammary symmetry." Patients with complications scored significantly lower on several domains of the BREAST-Q and in various cosmetic outcome categories. In this cohort, an overall complication rate of 18.7% was observed. Patients were generally satisfied, and most cosmetic outcomes were good to excellent. Volume displacement or replacement techniques were performed for different indications and generally showed comparable results. Expected differences in physical discomfort and symmetry between both techniques were observed. In addition, the occurrence of complications resulted in lower patient satisfaction and cosmetic outcomes. These findings emphasize the importance of thorough preoperative counselling.

Performance of Geopolymer Mortar and Steel Fiber Reinforced Geopolymer Mortar on Rehabilitation of Seismically Detailed Beam-Column Joint

ABSTRACT Recently, it was reported that seismically detailed beam-column joint suffered from joint damage during earthquake. Performance of geopolymer as repair material for seismically detailed beam-column joint following removal and replacement technique under cyclic loading is yet to be explored. Experimental program was carried out to examine suitability of geopolymer mortar (GM) and steel fiber reinforced geopolymer mortar (GMSF) to rehabilitate seismically detailed beam-column joint under cyclic loading. It was observed that GM failed to restore cyclic performance of rehabilitated specimens, whereas specimens rehabilitated with GMSF showed better performance in terms of stiffness degradation, ductility, energy dissipation, and damage index.

The Safety of Fat Grafting: An Institutional Retrospective Review.

Autologous fat grafting is a popular technique for volume replacement in the breast and face. The efficacy, safety, and complication rate of this technique at the division of plastic surgery at the University of Alabama at Birmingham will be described in this review. An institutional review board-approved retrospective review of patients undergoing fat grafting procedures from January 2015 to July 2018 was performed. Records were reviewed for fat graft recipient site, donor site, amount grafted, and complications. Continuous variables were compared using either a t test or one-way analysis of variance test. Categorical data were compared using χ2 test. A P value of 0.05 or less was considered statistically significant for all comparisons. A total of 396 patients who underwent fat grafting procedures of the face and body from January 2015 through July 2018 met inclusion criteria. Average amount of fat grafted for all grafts was 124.4 +/- 6.74 grams. Two hundred fifty of the grafts (62.7%) involved the bilateral breasts with an average of 140.6 +/- 93.97 g used, 70 per side. Of the 396 patients, 110 (27.8%) experienced complications. Forty three of the complications (10.9%) were considered to be major, which included hematomas/seromas, fat necrosis, dermatitis/cellulitis, and infection. No statistical differences were seen among recipient site complication rate. Types of minor complications were statistically significant per recipient sites with bilateral breasts more likely to experience asymmetry than the other recipient sites (20% for bilateral breasts vs 16% overall, P < 0.05). Fifty nine of the 110 patients (53.6%) had the complications reported to be resolved. Fat grafting is a reliable method for volumization of the breasts and face. Minor complications were not infrequent in this case series; however, no life-threatening complications were observed. Continued work needs to be done to use fat grafting beyond traditional measures.

A Review of Population Pharmacokinetic Analyses of Linezolid.

In recent years, many studies on population pharmacokinetics of linezolid have been conducted. This comprehensive review aimed to summarize population pharmacokinetic models of linezolid, by focusing on dosage optimization to maximize the probability of attaining a certain pharmacokinetic-pharmacodynamic parameter in special populations. We searched the PubMed and EMBASE databases for population pharmacokinetic analyses of linezolid using a parametric non-linear mixed-effect approach, including both observational and prospective trials. Of the 32 studies, 26 were performed in adults, four in children, and one in both adults and children. High between-subject variability was determined in the majority of the models, which was in line with the variability of linezolid concentrations previously detected in observational studies. Some studies found that patients with renal impairment, hepatic failure, advanced age, or low body weight had higher exposure and adverse reactions rates. In contrast, lower concentrations and therapeutic failure were associated with obese patients, young patients, and patients who had undergone renal replacement techniques. In critically ill patients, the inter-individual and intra-individual variability was even greater, suggesting that this population is at an even higher risk of underexposure and overexposure. Therapeutic drug monitoring may be warranted in a large proportion of patients given that the Monte Carlo simulations demonstrated that the one-size-fits-all labeled dosing of 600 mg every 12 h could lead to toxicity or therapeutic failure for high values of the minimum inhibitory concentration of the target pathogen. Further research on covariates, including renal function, hepatic function, and drug–drug interactions related to P-glycoprotein could help to explain variability and improve linezolid dosing regimens.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40262-022-01125-2.

David Procedure as Valve-Sparing Root Replacement.

Composite replacement of the aortic root and aortic valve is a valid surgical strategy in a case of annuloaortic ectasia. However, valve-sparing root replacement procedures have become the gold standard in cases with a morphologically intact or at least repairable aortic valve, and offer several advantages compared to conventional replacement techniques. Above all, the David procedure has become established as a well-known valve-sparing root replacement strategy with excellent short- and long-term outcomes, and it has been further applied to additional patient populations with characteristics like a bicuspid aortic valve or in the setting of acute type A aortic dissection. This narrative review offers an overview of the indications as well as the surgical steps of the T. David V procedure, and highlights important key points regarding the surgical feasibility and criteria of patient selection for valve-sparing root replacement.

Osteochondral lesion of the talus: still a problem?

Osteochondral lesion of the talus (OLT) often occurs after ankle trauma or repetitive micro-traumata, whereas the actual etiology remains unclear. The most common symptoms are local pain deep in the medial or lateral ankle that increases with weight-bearing and activity, accompanied by tenderness and swelling.Eventually, most patients with symptomatic or unstable OLT require surgery. Many reasonable operative techniques have been described, whereas most lead to similar and satisfactory results. They can be divided into cartilage repair, cartilage regeneration and cartilage replacement techniques. The OLT size and morphology in the first place but also surgeon and individual patient aspects are considered when it comes to surgery.For high postoperative success and low recurrence rates, underlying causes, for example, ligamentous instability and hindfoot malalignment should also be addressed during surgery.

Finding complete minimum driver node set with guaranteed control capacity

A critical prerequisite for controlling complex networks is to find a driver node set with a structural controllability guarantee. This paper introduces the control capacity for a driver node set and solves the problem of finding a complete minimum driver node set that not only guarantees network structural controllability but achieves the desired level of control capacity. A novel algorithmic framework is proposed which is based on the concept of equivalent set and approximate matching replacement technique. The proposed algorithmic framework is shown to outperform the state-of-the-art approaches in the literature. The validity of the proposed algorithm is analyzed and the performance is evaluated by experiments on artificial and real-world complex networks.

Early outcomes of the suprasternal transcatheter aortic valve replacement technique.

Transcatheter aortic valve replacement (TAVR) is now an established treatment option for patients with severe aortic stenosis. The most utilized approach remains transfemoral. In patients with difficult femoral access a variety of alternate approaches have been used. Recently, suprasternal access has emerged as a viable alternate approach in patients with very complex vascular access. We describe our 30-day outcomes of patients who underwent suprasternal transcatheter aortic valve replacement (suprasternal [SS]-TAVR), which constitutes the largest single-center cohort to date. From May 2016 to September 2021, 658 patients underwent TAVR at our institution. Of which 29underwent SS-TAVR. We performed a retrospective analysis to evaluate early (30 days) outcomes of this procedure. Main outcomes evaluated included 30-day mortality, stroke and pacemaker rates, length of stay, readmission, and valvular function. All patients were alive 30 days after the procedure. The median hospital length-of-stay was 2 days. Two patients (6.9%) had a stroke on the contra-lateral side of access. Two patients (6.90%) had significant cardiac arrhythmias requiring pacemaker placement. In 30 days, one patient was readmitted (3.45%). Our data confirmthe SS-TAVR as a feasible and safe alternative with comparable results to established approaches in patients who are unsuitable for femoral artery access and offers clinicians another access site in patients with very complex anatomy.

Bilateral oncoplastic breast-conserving surgery with volume replacement technique using the omental flap: a case report

BackgroundMany oncoplastic volume replacement techniques have been reported, however, it is generally difficult to utilize a single distant flap for bilateral breast carcinomas.Case presentationWe report a case of bilateral multiple breast carcinomas successfully treated with immediate volume replacement technique with an omental flap. Bilateral partial mastectomies were performed for bilateral breast carcinomas (one in the left breast and two in the right breast). The pedicled omental flap was laparoscopically harvested, and divided at the mid-portion of the flap. The proximal half of the flap was used to fill the right defect, and the distal half of the flap filled two defects in the left breast. Cosmetic outcome was excellent with minimal donor-site scars.ConclusionsThe omental flap can be considered for highly selected patients with bilateral breast carcinomas.

Aortic valve reimplantation in patients with Marfan and other connective tissue syndromes: a success story for these patients!

After the introduction of aortic valve (AV) and root replacement (Bentall–De Bono procedure), survival changed dramatically for patients with AV and/or root pathologies, including patients with Marfan syndrome or other genetic connective tissue diseases (CTD) [1, 2]. Since the latter mentioned patients are presented for surgery at a very young age, mechanical prosthesis is generally chosen over the biological. The consequent need for life-long anticoagulation exposes the patients to the potential, sometimes severe complications accounting up to 5% per year [3]. Due to this fact, AV-sparing techniques have been evolving over the last 30 years. Especially, AV reimplantation, as described by David and Feindel in 1992, became the standard technique for valve-sparing aortic root replacement with excellent short- and long-term results, even in patients with Marfan syndrome or other CTD [2, 4, 5]. In this issue of the European Journal of Cardiothoracic Surgery, Gil et al. describe their experience with AV reimplantation (David operation) in 157 patients with Marfan syndrome (143 patients) and other CTD [6]. The presented cohort is one of the largest published yet. The early- and long-term outcomes (median of 7.3 years) are impressively good. Especially, survival at 10 and 15 years with 98% is excellent and not different to the general Spanish population for the same age and gender. Furthermore, reported freedom from greater than moderate aortic regurgitation and reintervention were 90% and 96% at 10 years, respectively. Importantly, all these patients were operated by the same cardiosurgical team. The clear message that can be derived from this article is that David operation is an excellent option for the surgical treatment of these patients. The authors also conclude these patients should be centralized in referral centres and operated by very experienced surgeons. Finally, based on these results, authors postulate the threshold for prophylactic surgery in CTD should be reviewed and lowered.

MO473: Conservative Management in Hospitalized Patients With Advanced Chronic Kidney Disease—A Single Centre 4-Years’ Experience

Abstract BACKGROUND AND AIMS There is an increasing number of patients with advanced chronic kidney disease (CKD) who are older, frail, with multi-morbidity, and with poor functional status. Renal palliative medicine or kidney supportive care is an evolving branch of nephrology. In medicine, strict respect for the patient's wishes related to their health is essential, but the medical decision to suspend or not initiate treatments considered inappropriate or futile is also crucial, whenever the limits of diagnostic and/or therapeutic intervention dictated by the current state of knowledge are exceeded. There is a need for better evidence about medical management versus dialysis at different ages, to better support our patients in all stages of their renal disease. The aim of this study was to analyze the applicability and outcomes of a conservative management of advanced CKD in patients admitted to a nephrology ward between January 2018 and December 2021. METHOD Retrospective observational study was carried out through the analysis of digital data of all patients admitted to a nephrology ward between January 2018 and December 2021. All the patients included in this study had a decision of therapeutic limitation signed. This was applicable in situations of advanced illness and at the end stage of life, in which the use of extraordinary means for sustaining life may be considered inappropriate, or even a cause of damage. Therapeutic limitation parameters include the artificial route for nutrition, parenteral nutrition, use of vasoactive drugs, transfusions, invasive mechanical ventilation, defibrillators, cardiopulmonary resuscitation and renal function replacement techniques. Data regarding patients’ baseline characteristics, the Katz Index of independence in activities of daily living, comorbidities, symptoms, laboratory findings, length of hospital stay, treatment regimens and clinical outcomes were collected by consulting electronic medical records. Statistical analyses were performed using SPSS statistics version 23.0. RESULTS A total of 102 patients (female 55.9%) with a mean age of 86 ± 9 (range 55–99) years were selected. Prior to hospitalization, patients were mostly residing in nursing homes (n = 41, 40.2%), followed by their private residences (n = 40, 39.2%) and then continuous care units (n = 16, 15.7%). Diseases of the respiratory tract were the most common causes of hospitalization (n = 21, 20.7%), followed by acute kidney injury/worsening of CKD (n = 20, 19.6%) and heart failure (n = 15, 14.8%). We defined two groups: patients who died (group 1) and patients who were discharged (group 2). G1 (n = 88; 86.3%) and G2 (n = 14; 13.7%) had similar distributions of gender (female: 50.7% versus 54.9%, P = .081) opposite to age (82.9 ± 9 versus 73.8 ± 10 years, P = .016). At admission, groups were compared for dementia (62.1% versus 47.4%, P &amp;lt; .001), arterial hypertension (48.3% versus 37.9%, P = .061), diabetes (52.2% versus 37.8%, P &amp;lt; .001), oncologic disease (50.4% versus 26.6%, P &amp;lt; 0.001), hypoalbuminaemia (serum albumin &amp;lt;3.0 g/dL) (57.7% versus 59.9%, P = .056) and Katz Index of independence in activities of daily living &amp;lt;3 points (66.9% versus 62.3%, P = .081). Dialysis was suspended (n = 89; 87%) or not started (n = 13; 13%) in the number total of patients. A total of 86.3% of patients died (n = 88). The average number of days between the decision to limit therapy and death was 7 days (ranging from 1 to 23 days). The rest of the patients were discharged from the hospital, maintaining the conservative strategy. CONCLUSION Currently, we have a group of patients with CKD who are older and have more comorbidities. As demonstrated in our study, conservative management or the suspension of supportive treatment is a legitimate option for frail, elderly CKD patients in whom dialysis may not lead to an improvement in quality or duration of life. In fact, it is possible to medically ∼10%–15% of patients with advanced CKD and refer them to a renal palliative care consultation.

FC090: Stevia as an Alternative Osmotic Agent for Peritoneal Dialysis Fluid

Abstract BACKGROUND AND AIMS Peritoneal dialysis (PD) is a renal replacement technique that requires repeated contact of the peritoneum with hyperosmolar fluids. Unfortunately, it generates metabolic and biomechanical insults that promote structural and functional alterations of the peritoneal membrane (PM). PM is lined by a mesothelial cells (MCs) monolayer that is in direct contact with the PD fluids (PDFs). Repeated PDF exposure causes a mesothelial–mesenchymal transition (MMT) of the MCs, as well as an inflammatory response, angiogenesis and fibrosis of the peritoneal tissue. For decades, glucose (Gl) has been the most commonly used osmotic agent, and Gl itself is responsible for the aforementioned changes. Furthermore, Gl degradation products (GDPs) contribute to deleterious effects on the PM [1]. Therefore, there is an unmet need for more biocompatible osmotic agents able to better maintain the structure and function of the PM. Here we evaluated the biocompatibility of Stevia (STV), a compound of natural origin with a mixture of glycosides. STV has a molecular weight close to the theoretical ideal weight for an osmotic agent in PD [2] and it was used instead of Gl for PDF. METHODS The osmotic capacity of STV-containing fluids was analysed using an in vitro device with artificial membranes and compared to Gl-based fluids. In order to investigate the STV biocompatibility, human omental peritoneal mesothelial cells (HOMCs) were cultured in the presence of different types of Gl-based PDFs (Conventional 4.25% Gl solution with a high GDP level and biocompatible 2.3% Gl solution with low GDPs level), STV-based fluids or TGF-b for 48 h. Mice submitted to surgery of an intraperitoneal catheter insertion were treated for 40 days with STV- or Gl-based PDFs. Peritoneal tissues were collected to determine thickness, MMT, angiogenesis and inflammatory markers, as well as effluents to analyse infiltrating cells. RESULTS Experimentally, using artificial membranes we demonstrated that 1, 0.75 and 0.5% STV-based fluids have a maintained and prolonged osmotic capacity similar to commercial PDFs containing Gl concentrations between 1.5 and 2.3%. Moreover, 1.5% STV-based fluid showed an osmotic capacity higher than a PDF with Gl 2.3% and reached values similar to Gl 4.25% at longer time points. In addition, HOMCs exposed to STV-based fluids showed higher viability and did not induce MMT. Gl-based fluids induced upregulation of mesenchymal markers (VEGF, fibronectin, snail) and also downregulation of the epithelial marker E-cadherin in the case of the highest concentration of Gl (4.25%). None of these markers were significantly affected by STV treatment. In vivo, STV-based fluids preserved MCs monolayer and induced less PM thickness (Figure 1), angiogenesis, leukocyte infiltration and MMT than Gl-based fluids. Furthermore, STV solutions did not promote the release of pro-inflammatory cytokines by HOMCs nor by cells present in mice parietal peritoneal tissue in contrast to Gl-based PDFs. CONCLUSIONS STV-based fluids showed better biocompatibility than Gl-based PDFs in vivo and ex vivo since STV did not induce PM thickness, MMT, angiogenesis or the release of pro-inflammatory cytokines.