Bioactive Sambong oil-loaded electrospun cellulose acetate nanofibers: Preparation, characterization, and in-vitro biocompatibility.

Blumea balsamifera oil loaded cellulose acetate nanofiber mats were prepared by electrospinning. The inclusion of blumea oil increased the nanofiber diameter. FTIR spectra confirm the addition of blumea oil in the nanofiber mats. The XRD pattern suggests that the inclusion of blumea oil has caused a misalignment in the polymer chains of the cellulose acetate. Thus, a decrease in the tensile strength was observed for the blumea oil loaded nanofibers. The increase in fiber diameter causes a reduction in the porosity of the nanofiber mats. The blumea oil loaded nanofiber mats showed antibacterial efficacy against Escherichia coli and Staphylococcus aureus. The blumea oil showed antioxidant abilities against the DPPH solution. MVTR of the neat and blumea oil loaded nanofiber mats was in the range of 2450-1750 g/m2/day, which is adequate for the transport of air and moisture from the wound surface. Blumea oil loaded mats showed good cell viability ~92% for NIH 3T3 cells in more extended periods of incubation. A biphasic release profile was obtained, and the release followed the first-order kinetics depending upon the highest value of the coefficient of correlation R 2 (88.6%).

Alumina Ceramic Exacerbates the Inflammatory Disease by Activation of Macrophages and T Cells.

(1) Background: Aluminum oxide (Al2O3) ceramic is one of the materials used for artificial joints, and it has been known that their fine particles (FPs) are provided by the wear of the ceramic. Al2O3 FPs have been shown to induce macrophage activation in vitro; however, the inflammatory effect in vivo has not been studied. (2) Methods: We examined the in vivo effect of Al2O3 FPs on the innate and adaptive immune cells in the mice. (3) Results: Al2O3 FPs promoted the activation of spleen macrophages; however, conventional dendritic cells (cDCs), plasmacytoid DCs (pDCs), and natural killer (NK) cells were not activated. In addition, increases in the CD4 and CD8 T cells was induced in the spleens of the mice treated with Al2O3 FPs, which differentiated into interferon-gamma (IFN-γ)-producing helper T1 (Th1) and cytotoxic T1 (Tc1) cells. Finally, the injection of Al2O3 FPs exacerbated dextran sulfate sodium (DSS)-induced inflammation in the colon, mediated by activated and increased number of CD4 and CD8 T cells. (4) Conclusions: These data demonstrate that FPs of Al2O3 ceramic may contribute to the exacerbation of inflammatory diseases in the patients.

Design, characterization, and evaluation of antibacterial gels, Boc-D-Phe-γ4-L-Phe-PEA/chitosan and Boc-L-Phe-γ4-L-Phe-PEA/chitosan, for biomaterial-related infections.

Self-assembled peptide gels have generated interest as antibacterial materials to prevent biomaterial-related infections but these peptides are often associated with poor proteolytic stability. Efforts have been made to stabilize peptides by incorporating non-natural amino acids and/or linkages but complexation with polymers have not been explored. Therefore, we developed self-assembled peptide/chitosan gels, Boc-D-Phe-γ4-L-Phe-PEA (NH007)/chitosan and Boc-L-Phe-γ4-L-Phe-PEA (NH009)/chitosan, by complexing dipeptide NH007 or NH009 with chitosan in DMSO:acetic acid. The gels were characterized using SEM, FTIR, contact angle, and rheology data and found to exhibit excellent viscoelastic and self-healing characteristics. Complexation with chitosan led to an increase in stability against proteolytic degradation. Peptide/chitosan gels showed broad spectrum antibacterial activities against Gram-negative and Gram-positive bacteria, such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis at a high inoculum of 107-108 cfu/mL. NH007/chitosan gels showed 70-75% inhibition, whereas NH009/chitosan showed 78-81% inhibition and NH009/chitosan gels, in particular, showed strong antibacterial activity against pathogenic strain of P. aeruginosa. A unique feature of these gels is that the antibacterial activities did not decrease gradually but were sustained for up to 48 h. The mechanistic studies using SEM and HR-TEM indicated interaction of gels with bacterial membrane components, leading to cell lysis. The MTT and LDH assays indicated >90% cell viability and only 8-10% toxicity towards NIH 3T3 fibroblast cells. Thus, peptide/chitosan gels developed in the present work showed improved proteolytic stability and sustained antibacterial activities and, therefore, may be used for preventing biomaterial-related infections.

Hyperbaric oxygen therapy for dermal ischemia after dermal filler injection with calcium hydroxylapatite: a case report.

Dermal injection of fillers is a popular and relatively safe aesthetic procedure. Severe complications are rare, but they do occur. One of the most threatening complications after dermal filler injection is skin necrosis due to vascular occlusion. Different treatment options are available, including the use of hyperbaric oxygen (HBO2) therapy. A 46-year-old female received facial dermal filler injections with calcium hydroxylapatite at an aesthetic clinic. A few days after injection she developed a burning pain, numbness of the skin and white discoloration in the injected area. Two days after injection treatment was started with hyaluronidase and warm compresses. In addition, the patient received prednisolone, sildenafil and nifedipine. After the start of these treatments, the pain, numbness and discoloration of the skin persisted. Because of dermal ischemia and to improve healing she was referred for HBO2. Treatment consisted of 10 sessions of 100% oxygen for 90 minutes in a multiplace chamber at 2.5 atmospheres absolute pressure. During HBO2 the discoloration resolved, pain and numbness disappeared, and the tissue healed completely. After a six-month follow-up she had an excellent cosmetic outcome. Given the pathophysiologic mechanisms of vascular complications after dermal filler injection, HBO2 should be considered when treating these complications.

Artificial shear stress effects on leukocytes at a biomaterial interface.

Medical devices, such as ventricular assist devices (VADs), introduce both foreign materials and artificial shear stress to the circulatory system. The effects these have on leukocytes and the immune response are not well understood. Understanding how these two elements combine to affect leukocytes may reveal why some patients are susceptible to recurrent device-related infections and provide insight into the development of pump thrombosis. Biomaterials-DLC: diamond-like carbon-coated stainless steel; Sap: single-crystal sapphire; and Ti: titanium alloy (Ti6 Al4 V) were attached to the parallel plates of a rheometer. Whole human blood was left between the two discs for 5 minutes at +37°C with or without the application of shear stress (0 s-1 or 1000 s-1 ). Blood was removed and used for complete blood cell counts, flow cytometry (leukocyte activation, cell death, microparticle generation, phagocytic ability, and reactive oxygen species [ROS] production), and the production of pro-inflammatory cytokines. L-selectin expression on monocytes was decreased when blood was exposed to the biomaterials both with and without shear. Applying shear stress to blood on a Sap and Ti surface led to activation of neutrophils shown as decreased L-selectin expression. Sap and Ti blunted the LPS-stimulated macrophage migration inhibitory factor (MIF) production, most notably when sheared on Ti. The biomaterials used here have been shown to activate leukocytes in a static environment. The introduction of shear appears to exacerbate this activation. Interestingly, a widely accepted biocompatible material (Ti) utilized in many different types of devices has the capacity for immune cell activation and inhibition of MIF secretion when combined with shear stress. These findings contribute to our understanding of the contribution of biomaterials and shear stress to recurrent infections and vulnerability to sepsis in some VAD patients as well as pump thrombosis.

Light Perception Vision Recovery After Treatment for Calcium Hydroxylapatite Cosmetic Filler-Induced Blindness.

A 51-year-old woman presented with no light perception vision of the right eye 12 hours after another provider injected calcium hydroxylapatite into the glabella and dorsum of the nose. Exam and fluorescein angiography demonstrated optic nerve edema and choroidal hypoperfusion consistent with ischemia of the posterior ciliary circulation. The central retinal circulation appeared intact. One thousand two hundred units of retrobulbar hyaluronidase were injected urgently in several boluses. Oral prednisone and aspirin also were administered. Ocular massage was also initiated. One day later, visual acuity improved to light perception that remained stable at 3 months. Retrobulbar hyaluronidase injection, ocular massage, prednisone, and aspirin were correlated to recovery of light perception vision in this case of calcium hydroxylapatite filler embolization to the choroidal circulation. The mechanism for the recovery of some vision and the role of hyaluronidase and other medications remain uncertain. Further research in treatments for ophthalmic complications of facial fillers is warranted.

Alumina Biocompatibility.

Alumina (Al2O3) ceramic is widely used for medical devices and its biocompatibility is well known and is reported in articles and textbooks. However, finding proof of this assertion gathered over more than 40 years can be challenging. We performed a literature review about alumina biocompatibility to compile data from the literature. We searched for articles on the biocompatibility of alumina in relation to the ISO 10993-1 International Standard, which defines the biocompatibility of biomaterials. For every biological effect listed in the norm, such as cytotoxicity, sensitization, implantation, and genotoxicity, in vitro and in vivo tests in animals and humans did not reveal any abnormal biological response. Proof for the the well-known biocompatibility of alumina is summarized in this review.

Autoimmune/inflammatory syndrome induced by adjuvants-ASIA-related to biomaterials: analysis of 45 cases and comprehensive review of the literature.

Systemic autoimmune or granulomatous disorders related to biomaterials of human use have rarely been described. The aim of this study was to report cases of autoimmune/inflammatory syndrome induced by adjuvants (ASIA) related to biomaterial injections and prostheses, mainly silicone, hyaluronic acid, acrylamides and methacrylate compounds in a Spanish patient cohort. This study is a retrospective analysis of clinical, laboratory, histopathological and follow-up data of 45 cases of patients suffering from late-onset, non-infectious inflammatory/autoimmune disorders related to bioimplants. Late onset was defined as 3 months or more post injection. Data were obtained through a further non-systematic but comprehensive review of the literature. Forty-five cases of late-onset adverse reactions related to biomaterial injections or prostheses were reviewed. All cases had systemic complaints that could be categorised as ASIA. In all but four patients, inflammatory features at the implantation site preceded distant or systemic manifestations. Abnormal blood tests were common. Localised inflammatory nodules and panniculitis in 40/45 (88.88%) evolved into a variety of disorders, viz., primary biliary cirrhosis, Sjögren's syndrome, sarcoidosis, human adjuvant disease, vasculitis, inflammatory bowel syndrome and inflammatory polyradiculopathy. Five (11.11%) cases presented primarily with systemic autoimmune disorders. Biomaterials and prostheses can provoke late-onset systemic autoimmune disorders fulfilling ASIA criteria, or present primarily local/regional inflammatory reactions that may eventually evolve into systemic autoimmune and/or granulomatous disorders which fall under ASIA.

In vivo characterization of a new type of biodegradable starch microsphere for transarterial embolization.

Transarterial embolization is an established minimally invasive treatment for solid tumors. Unintended inflammation, foreign body reactions and ischemia-triggered neoangiogenesis are clinical drawbacks of permanent embolic materials. The aim of the current study was to characterize a new type of biodegradable starch microsphere with regard to angiographic and histopathological features such as patterns of acute arterial occlusion as well as induction of tissue necrosis, microsphere biodegradation, and inflammation and foreign body reactions during follow-up. Key characteristics of both biodegradable prototypes (L1 and L2; prototype groups) were as follows: microspheres are biodegradable by serum α-amylase, produced from chemically crosslinked potato starch to different extents, in a diameter range of ∼300-800 µm, differing in size distribution and featuring a microsphere deformation of ∼1%. In vivo transarterial embolization with L1 and L2, while applying clinical standard techniques, was performed and compared with clinically established permanent microspheres (Embosphere®500-700 and Embosphere®700-900; control groups). Twenty-four pig kidneys were embolized with the different embolic materials by following the study protocol, and there were no technical failures or complications. Parenchymal necrosis with interstitial calcification was observed in all kidneys independent of the type of embolic material used. Compared with the permanent embolic materials, biodegradable microspheres showed complete (L1) or partial (L2) biodegradation within one week after transarterial embolization, and induced a comparable (L1) or a lower (L2) degree of arterial wall necrosis and a lower degree of inflammation and foreign body reactions. In conclusion, the presented new type of biodegradable microsphere is promising, and could be further evaluated in terms of clinical translation.

Effect of the incorporation of chitosan on the physico-chemical, mechanical properties and biological activity on a mixture of polycaprolactone and polyurethanes obtained from castor oil.

In the present study, polyurethane materials were obtained from castor oil, polycaprolactone and isophorone diisocyanate by incorporating different concentrations of chitosan (0.5, 1.0 and 2.0% w/w) as an additive to improve the mechanical properties and the biological activity of polyurethanes. The polyurethanes were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, stress/strain fracture tests and swelling analysis, and the hydrophilic character of the surface was determined by contact angle trials. The objectives of the study were to evaluate the effect of the incorporation of chitosan on the changes of the physico-chemical and mechanical properties and the in vitro biological activity of the polyurethanes. It was found that the incorporation of chitosan enhances the ultimate tensile strength of the polyurethanes and does not affect the strain at fracture in polyurethanes with 5% w/w of polycaprolactone and concentrations of chitosan ranging from 0 to 2% w/w. In addition, PCL5-Q-PU formulations and their degradation products did not affect cell viability of L929 mouse fibroblast and 3T3, respectively. Polyurethane formulations showed antibacterial activities against Staphylococcus aureus and Escherichia coli bacteria. The results of this study have highlighted the potential biomedical application of this polyurethanes related to soft and cardiovascular tissues.

Thermal-Responsive Behavior of a Cell Compatible Chitosan/Pectin Hydrogel.

Biopolymer hydrogels are important materials for wound healing and cell culture applications. While current synthetic polymer hydrogels have excellent biocompatibility and are nontoxic, they typically function as a passive matrix that does not supply any additional bioactivity. Chitosan (CS) and pectin (Pec) are natural polymers with active properties that are desirable for wound healing. Unfortunately, the synthesis of CS/Pec materials have previously been limited by harsh acidic synthesis conditions, which further restricted their use in biomedical applications. In this study, a zero-acid hydrogel has been synthesized from a mixture of chitosan and pectin at biologically compatible conditions. For the first time, we demonstrated that salt could be used to suppress long-range electrostatic interactions to generate a thermoreversible biopolymer hydrogel that has temperature-sensitive gelation. Both the hydrogel and the solution phases are highly elastic, with a power law index of close to -1. When dried hydrogels were placed into phosphate buffered saline solution, they rapidly rehydrated and swelled to incorporate 2.7× their weight. As a proof of concept, we removed the salt from our CS/Pec hydrogels, thus, creating thick and easy to cast polyelectrolyte complex hydrogels, which proved to be compatible with human marrow-derived stem cells. We suggest that our development of an acid-free CS/Pec hydrogel system that has excellent exudate uptake, holds potential for wound healing bandages.

Inflammatory response to nano- and microstructured hydroxyapatite.

The proliferation and activation of leukocytes upon contact with a biomaterial play a crucial role in the degree of inflammatory response, which may then determine the clinical failure or success of an implanted biomaterial. The aim of this study was to evaluate whether nano- and microstructured biomimetic hydroxyapatite substrates can influence the growth and activation of macrophage-like cells. Hydroxyapatite substrates with different crystal morphologies consisting of an entangled network of plate-like and needle-like crystals were evaluated. Macrophage proliferation was evaluated on the material surface (direct contact) and also in extracts i.e. media modified by the material (indirect contact). Additionally, the effect of supplementing the extracts with calcium ions and/or proteins was investigated. Macrophage activation on the substrates was evaluated by quantifying the release of reactive oxygen species and by morphological observations. The results showed that differences in the substrate's microstructure play a major role in the activation of macrophages as there was a higher release of reactive oxygen species after culturing the macrophages on plate-like crystals substrates compared to the almost non-existent release on needle-like substrates. However, the difference in macrophage proliferation was ascribed to different ionic exchanges and protein adsorption/retention from the substrates rather than to the texture of materials.

Human adjuvant-related syndrome or autoimmune/inflammatory syndrome induced by adjuvants. Where have we come from? Where are we going? A proposal for new diagnostic criteria.

In 1964, Miyoshi reported a series of patients with diverse symptoms after receiving treatment with silicone or paraffin fillers. Miyoshi named this condition 'human adjuvant disease'. Since then, the literature has been flooded with case reports and case series of granulomatous and systemic autoimmune disorders related to vaccines, infection or other adjuvants such as silicone and other biomaterials. A new term -autoimmune/inflammatory syndrome induced by adjuvants--has recently been coined for a process that includes several clinical features previously described by Miyoshi plus other clinical and laboratory parameters related to exposure to diverse external stimuli. Disorders such as siliconosis, Gulf War syndrome, macrophagic myofasciitis syndrome, sick building syndrome and post-vaccination syndrome have been included in autoimmune/inflammatory syndrome induced by adjuvants. Disorders such as Spanish toxic oil syndrome and Ardystil syndrome could also be included. Furthermore, biomaterials other than silicone should also be considered as triggering factors for these adjuvant-related syndromes. New diagnostic criteria in this field have been proposed. Nevertheless, many of these criteria are too subjective, leading to some patients being diagnosed with chronic fatigue syndrome or other 'central sensitization syndromes'. Diagnostic criteria based only on objective clinical and laboratory data to be further discussed and validated are proposed herein.

Efficacy and safety of the C-Qur™ Film Adhesion Barrier for the prevention of surgical adhesions (CLIPEUS Trial): study protocol for a randomized controlled trial.

BACKGROUND: Adhesions develop in over 90% of patients after intra-abdominal surgery. Adhesion barriers are rarely used despite the high morbidity caused by intra-abdominal adhesions. Only one of the currently available adhesion barriers has demonstrated consistent evidence for reducing adhesions in visceral surgery. This agent has limitations through poor handling characteristics because it is sticky on both sides. C-Qur™ Film is a novel thin film adhesion barrier and it is sticky on only one side, resulting in better handling characteristics. The objective of this study is to assess efficacy and safety of C-Qur™ Film to decrease the incidence of adhesions after colorectal surgery. METHODS/DESIGN: This is a prospective, investigator initiated, randomized, double-blinded, multicenter trial. Eligible patients undergoing colorectal resection requiring temporary loop ileostomy or loop/split colostomy by laparotomy or hand assisted laparoscopy will be included in the trial. Before closure, patients are randomized 1:1 to either the treatment arm (C-Qur™ Film) or control arm (no adhesion barrier). Patients will return 8 to 16 weeks post-colorectal resection for take down of their ostomy. During ostomy takedown, adhesions will be evaluated for incidence, extent, and severity. The primary outcome evaluation will be assessment of adhesions to the incision site. It is hypothesized that the use of C-Qur™ Film underneath the primary incision reduces the incidence of adhesion at the incision by 30%. To demonstrate 30% reduction in the incidence of adhesions, a sample size of 84 patients (32 + 10 per group (25% drop out)) is required (two-sided test, α = 0.05, 80% power). DISCUSSION: Results of this study add to the evidence on the use of anti-adhesive barriers in open and laparoscopic 'hand-assisted' colorectal surgery. We chose incidence of adhesions to the incision site as primary outcome measure since clinical outcomes such as small bowel obstruction, secondary infertility and adhesiolysis related complications are considered multifactorial and difficult to interpret. Incidence of adhesions at repeat surgery is believed to be the most valuable surrogate endpoint for clinically relevant adhesion prevention, since small bowel obstruction and adhesiolysis at repeat surgery are not likely to occur when complete adhesion reduction in a patient is accomplished. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT01872650, registration date 6 June 2013.

Bioactive magnetic nanoparticles of Fe-Ga synthesized by sol-gel for their potential use in hyperthermia treatment.

Hyperthermia is one of the most recents therapies for cancer treatment using particles with nanometric size and appropriate magnetic properties for destroying cancer cells. Magnetic nanoparticles (MNP's) of Fe-Ga and synthesized using a polycondensation reaction by sol-gel method were obtained. MNP's of Fe(1.4)Ga(1.6)O(4) that possess an inverse spinel structure were identified by X-Ray Diffraction, Transmission Electron Microscopy, Scanning Electron Microscopy and Energy Dispersive Spectroscopy. The results showed that the MNP's are composed only by Fe, Ga and O and their size is between 15 and 20 nm. The magnetic properties measured by Vibration Sample Magnetometry demonstrated a saturation magnetization value of 37.5 emu/g. To induce the MNP's bioactivity, a biomimetic method was used which consisted in the immersion of MNP's in a Simulated Body Fluid (SBF) for different periods of time (7, 14 and 21 d) along with a wollastonite disk. The formation of a bioactive layer, which closely resembles that formed on the existing bioactive systems and with a Ca/P atomic ratio within a range of 1.37-1.73 was observed on the MNP's. Cytotoxicity of MNP's was evaluated by in vitro hemolysis testing using human red blood cells at concentrations between 0.25 and 6.0 mg/mL. It was found that the MNP's were not cytotoxic at none of the concentrations used. The results indicate that Fe-Ga MNP's are potential materials for cancer treatment of both hard and soft tissue by hyperthermia and drug carriers, among other applications.

Aesthetic applications of calcium hydroxylapatite volumizing filler: an evidence-based review and discussion of current concepts: (part 1 of 2).

BACKGROUND: Calcium hydroxylapatite filler (CaHA; Radiesse) is a synthetic, non-animal derived product composed of minerals that occur naturally in bone and teeth. Following its development in the US, initial approval by the US FDA for non-aesthetic indications and CE marking in Europe, it was used off FDA-labeling for aesthetic purposes. Its use has grown further since its FDA approval in 2006 for long-lasting correction of moderate to severe wrinkles and folds. It is a popular filler for volume restoration to the face, and also to nonfacial areas such as the dorsum of the hands. METHODS: The first article of this two-part series provides an evidence-based review of study data pertaining to the mechanism of action and biocompatibility of CaHA filler, and its safety, efficacy and tolerability when used for aesthetic purposes. The review includes data from a number of prospective, controlled comparative studies, from several retrospective studies, and from a meta-analysis of reported complications from alloplastic filler procedures over a 20-year period. The study methodology and number of study subjects are sufficiently robust to provide a high Evidence Level for much of the data. RESULTS: CaHA has good safety, efficacy and tolerability profiles that are comparable to those of hyaluronic acid (HA) fillers. It provides an initial, immediate volume replacement for up to 12 months followed by longer term correction due to biostimulation, resulting in collagenesis. Evidence Level II studies show longevity of 30 months or more after nasolabial fold implantation. Other studies demonstrate the appropriateness of CaHA filler for volume restoration to areas including the mid face, lower face and hands. CaHA is classified as an adjustable filler, whereas HA is fully reversible by hyaluronidase digestion. For this reason, and also because of CaHA's high viscosity and elasticity, evidence-based and experiential consensus suggests its avoidance in highly mobile areas (e.g. lips) or in anatomically unforgiving areas (e.g. the periocular region), where there may be increased incidence of nodules. CONCLUSION: CaHA filler is safe, efficacious and well-tolerated when used appropriately. It is increasingly recognized that many patients require pan-facial volume restoration, and that many can benefit from combined treatments. Therefore, CaHA and HA fillers may be considered complementary rather than competitive to each other. The second article of this series offers a discussion of product characteristics, scientific principles and injection techniques to optimize treatment with CaHA filler, including special considerations for avoidance and management of complications.

Purpura and fillers: a review of pre-procedural, intra-procedural, and post-procedural considerations.

Injectable aesthetic fillers are associated with the common and expected side effect of purpura or bruising. There are pre-procedural, intra-procedural and post-procedural considerations that can potentially minimize bruising. Traditional and newer techniques are discussed in this review and the benefits and risks of each technique will be provided.

Evaluation of four biodegradable, injectable bone cements in an experimental drill hole model in sheep.

Four cement applications were tested in this investigation. Two dicalcium phosphate dihydrate (DCPD-brushite) hydraulic cements, an apatite hydraulic fiber loaded cement, and a calcium sulfate cement (Plaster of Paris) were implanted in epiphyseal and metaphyseal cylindrical bone defects in sheep. The in vivo study was performed to assess the biocompatibility and bone remodeling of four cement formulations. After time periods of 2, 4, and 6 months, the cement samples were clinically and histologically evaluated. Histomorphometrically, the amount of new bone formation, fibrous tissue, and bone marrow and the area of remaining cement were measured. In all specimens, no signs of inflammation were detectable either macroscopically or microscopically. Cements differed mainly in their resorption time. Calcium sulfate was already completely resorbed at 2 months and showed a variable amount of new bone formation and/or fibrous tissue in the original drill hole over all time periods. The two DCPD cements in contrast were degraded to a large amount at 6 months, whereas the apatite was almost unchanged over all time periods.

Bulking agents: an analysis of 500 cases and review of the literature.

INTRODUCTION AND HYPOTHESIS: Stress urinary incontinence (SUI) is common, impacts women's quality of life, and generates high costs. Physiotherapy is the first-line therapy, and if it fails, suburethral slings are the gold standard in SUI surgery. Bulking agents injected periurethrally might be a beneficial alternative, but there is a paucity of data on bulking therapy. The aim of this study was to prospectively analyze the efficacy and safety of bulking agents in the setting of a tertiary referral center. METHODS: In the last 13 years, 514 elderly women with SUI were treated by injection therapy with either collagen (Contigen), hyaluronic acid (Zuidex), ethylene vinyl alcohol (Tegress), or polyacrylamide hydrogel (Bulkamid). Subjective and objective outcome was recorded at the 12-month postoperative appointment using the King's Health Questionnaire, visual analogue scale (VAS) describing their incontinence severity, standardized pad test, and urethral pressure profile. RESULTS: Demographic data were equally distributed in all four groups of agents used. Sixty-one patients were lost to follow-up (10.6 %). Statistically significant changes were found for maximum urethral closure pressure (MUCP), pad weight, and VAS before and after bulking for the four agents used. Pad test was negative in 73.2 % of patients after bulking therapy. Subjective assessment showed improvements in general health and role limitations. The overall complication rate was low for all agents. CONCLUSIONS: This study shows improvement in incontinence after bulking therapy according to subjective and objective outcomes in an elderly population. In contrast to earlier reports, side effects due to injections were few and mild. We can advocate bulking therapy for treating SUI, as it is simple, safe, and shows both objective and subjective improvement and relief.