Impact of human umbilical cord-derived stem cells (HUMSCs) on host responses to a synthetic polypropylene mesh for pelvic floor reconstruction in a rat model.

In order to evaluate the effects of human umbilical cord-derived stem cells (HUMSCs) on the biocompatibility of and tissue response to a polypropylene (PP) mesh (Gynemesh™ PS) implanted in rat vaginas, HUMSCs were isolated and characterized in vitro and then combined with Gynemesh™ PS to create a tissue-engineered mesh. This tissue-engineered mesh and pure PP mesh were implanted in the submucosae of the posterior vaginal walls of rats. Mesh/tissue complexes were harvested at 1, 4 and 12 weeks after implantation. Histological evaluations including an assessment of the inflammatory reaction, neovascularization and fibrosis around the mesh fibers were performed and real-time quantitative polymerase chain reaction (RT-PCR) was used to analyze the mRNA expression of genes involved in wound healing at the tissue-mesh interface. After being seeded onto the PP mesh scaffold, HUMSCs grew and proliferated well in vitro culture. One week after implantation, the HUMSC-seeded mesh elicited a greater inflammatory response than the pure PP mesh (3.33 ± 0.21 vs. 2.63 ± 0.18, p = 0.026), while 4 and 12 weeks after implantation, the inflammatory response in the HUMSC-seeded mesh was lower than that in the unseeded mesh (p < 0.05). At 12 weeks, the HUMSC-seeded mesh induced a lower expression of matrix metalloproteinase (MMP)-1 and a higher expression of anti-inflammatory cytokine interleukin (IL)-4. HUMSCs may decrease the inflammatory response and improve the biocompatibility of a conventional synthetic mesh and may have the potential to reduce postoperative complications such as mesh exposure or erosion.

Physicochemical stability of an admixture of lidocaine and ketamine in polypropylene syringe used in opioid-free anaesthesia.

Objectives: Opioid-free anaesthesia is a treatment strategy of pain management based on the use of drugs such as lidocaine, ketamine and dexmedetomidine that do not interact significantly with opioid receptors. In particular, these drugs are used by anaesthesiologists to ensure adequate levels of analgesia during surgical procedures for burn patients such as daily wound dressings and graft surgeries. Furthermore, for hypothermia prevention and wound-healing purposes, ambient temperature must be kept high for these patients, usually between 27°C and 30°C. To facilitate the use of this technique, clinicians want to mix lidocaine and ketamine in the same syringe. No stability data is available to determine the feasibility of this admixture and at this temperature. The objective was to study the physicochemical stability of lidocaine 20 mg/mL with ketamine 2.5 mg/mL diluted with 0.9% sodium chloride (0.9% NaCl) stored at 28°C in polypropylene syringe for 48 hours. Methods: Physical stability was evaluated by visual examination and by measuring turbidity with a spectrophotometer. Chemical stability was determined after preparation and after 6, 24 and 48 hours of conservation with a high performance liquid chromatography and pH measurements. The method was validated according to International Conference on Harmonisation Q2(R1) guidelines. Results: Both lidocaine (99.98%±1.44%) and ketamine (100.70%±0.95%) retained more than 95% of their initial concentration after 48 hours storage. pH measurements remained stable over the course of the study (less than 0.21 point of variation). No signs of physical instability were observed after visual and subvisual inspections. Conclusions: The physicochemical stability of lidocaine 20 mg/mL and ketamine 2.5 mg/mL diluted with 0.9% NaCl in a polypropylene syringe stored at 28°C protected from light was demonstrated for 48 hours. This infusion technique is therefore feasible from a pharmaceutical point of view in burn-unit settings.

Consensus Statement of the European Urology Association and the European Urogynaecological Association on the Use of Implanted Materials for Treating Pelvic Organ Prolapse and Stress Urinary Incontinence.

CONTEXT: Surgical nonautologous meshes have been used for several decades to repair abdominal wall herniae. Implantable materials have been adopted for the treatment of female and male stress urinary incontinence (SUI) and female pelvic organ prolapse (POP). OBJECTIVE: A consensus review of existing data based on published meta-analyses and reviews. EVIDENCE ACQUISITION: This document summarises the deliberations of a consensus group meeting convened by the European Association of Urology (EAU) and the European Urogynecological Association, to explore the current evidence relating to the use of polypropylene (PP) materials used for the treatment of SUI and POP, with reference to the 2016 EAU guidelines (European Association of Urology 2016), the European Commission's SCENIHR report on the use of surgical meshes (SCENIHR 2015), other available high-quality evidence, guidelines, and national recommendations. EVIDENCE SYNTHESIS: Current data suggest that the use of nonautologous durable materials in surgery has well-established benefits but significant risks, which are specific to the condition and location they are used for. Various graft-related complications have been described-such as infection, chronic pain including dyspareunia, exposure in the vagina, shrinkage, erosion into other organs of xenografts, synthetic PP tapes (used in SUI), and meshes (used in POP)-which differ from the complications seen with abdominal herniae. CONCLUSIONS: When considering surgery for SUI, it is essential to evaluate the available options, which may include synthetic midurethral slings (MUSs) using PP tapes, bulking agents, colposuspension, and autologous sling surgery. The use of synthetic MUSs for surgical treatment of SUI in both male and female patients has good efficacy and acceptable morbidity. Synthetic mesh for POP should be used only in complex cases with recurrent prolapse in the same compartment and restricted to those surgeons with appropriate training who are working in multidisciplinary referral centres. PATIENT SUMMARY: Synthetic slings can be safely used in the surgical treatment of stress incontinence in both male and female patients. Patients need to be aware of the alternative therapy and potential risks and complications of this therapy. Synthetic mesh for treating prolapse should be used only in complex cases with recurrent prolapse in specialist referral centres.

Stability of 11 prevalent synthetic cannabinoids in authentic neat oral fluid samples: glass versus polypropylene containers at different temperatures.

Although synthetic cannabinoids have been intensively investigated in recent years and oral fluid testing is becoming increasingly popular in suspected driving under the influence of drugs cases, only scarce data on their stability in authentic neat oral fluid (nOF) samples are yet available. However, especially for these new psychoactive drugs, investigations focusing on stability issues are necessary as inappropriate storage conditions may lead to considerable analytical problems. Since it has been shown for Δ(9) -tetrahydrocannabinol that adsorption to plastic surfaces may lead to considerable drug loss, we aimed to evaluate whether adsorption also has to be taken into account for synthetic cannabinoids in nOF samples. In this paper, the results of investigations on the recovery of 11 prevalent synthetic cannabinoids from authentic nOF samples stored over 72 h in RapidEASE (high quality borosilicate glass) and Sciteck Saliva Split Collector (polypropylene) tubes at 4 and 25 °C are presented. Our findings clearly demonstrate that lipophilic synthetic cannabinoids present in nOF samples adsorb to the surface of polypropylene containers when stored at room temperature, leading to considerable drug loss. Hence, when using polypropylene tubes, samples should be shipped cooled in order to avoid a substantial decrease of the analyte concentration during transportation.

Managing wound exudate using a super-absorbent polymer dressing: a 53-patient clinical evaluation.

This real-life, observational evaluation shows that, by absorbing and retaining within its structure the corrosive enzymes found in chronic exudate, this dressing both reduces the likelihood of peri-wound maceration and promotes healing.

Stability of fentanyl 5 microg/mL diluted with 0.9% sodium chloride injection and stored in polypropylene syringes.

PURPOSE: The stability of fentanyl 5 microg/mL in 0.9% sodium chloride solution packaged in polypropylene syringes was studied. METHODS: Samples of fentanyl 5 microg (as the citrate) per milliliter in 0.9% sodium chloride injection were prepared and assessed for chemical stability using a validated, stability-indicating high- performance liquid chromatographic (HPLC) assay. A total of 12 syringe samples were submitted for chemical stability testing by HPLC. The syringes were protected from light and stored in controlled ambient conditions (23-27 degrees C and 55-65% relative humidity) in an environmental chamber. Three samples were tested initially and at each 30-day interval. Each syringe sample was tested with two determinations, using the average of the determinations for the assay result. Samples were assessed for pH and inspected for color and visible particulate matter. Stability was defined as the retention of 90-110% of the initial drug concentration at 30, 60, and 90 days. RESULTS: Fentanyl citrate injection maintained the appearance of a clear, colorless solution, with mean +/- S.D. pH values ranging from 4.13 +/- 0.01 to 4.52 +/- 0.02 throughout the study period. Recovery of fentanyl ranged from 99.86% +/- 0.29% to 102.74% +/- 1.60% of the initial concentration, with no detectable changes in the chromatographic profiles of all tested samples. CONCLUSION: Fentanyl 5 microg (as the citrate) per milliliter in 0.9% sodium chloride injection, packaged in polypropylene syringes and stored protected from light, was stable for at least 90 days in controlled ambient conditions.

Tensile properties of five commonly used mid-urethral slings relative to the TVT.

We characterized the tensile properties of five mid-urethral slings relative to the Gynecare TVT. Slings were divided and loaded to failure. The heat-sealed Boston Scientific mid-section and the American Medical Systems (AMS) tensioning suture were examined separately. Analysis of the resulting nonlinear load elongation curves included calculation of low and high stiffness, the transition point between them (inflection point), load at failure, and relative elongation. Permanent elongation was measured after repetitive loads. Mean values were compared using a one-way analysis of variance. The curves of the Gynecare, Boston Scientific (no midsection) and AMS (no suture) were nonlinear with similar low stiffness and inflection points. The Bard, Caldera, and Mentor slings were stiffer. Heat sealing the Boston Scientific mid-section increased stiffness, while the AMS suture had negligible effect. Cyclical loading induced permanent elongation that was similar for Gynecare, AMS, and Boston Scientific (without mid-section) and lower for Bard, Caldera, and Mentor. With the exception of AMS, the overall effect of newer sling modifications was an increase in tensile stiffness.

Tissue resistance of the tension-free procedure: what about healing?

The aim of our work was to objectify and quantify the mechanical benefits of healing with regards to tearing meshes off of tissues and maximal resistance after cicatrization. In vivo, we tested the mechanical gain in resistance by healing after implantation of a Prolene mesh. We measured the value of forces when traction was exerted until mobilization at different stages of cicatrization. Resistance increased progressively at the beginning of tissue inclusion. A maximal plateau was reached around the 25th day. It is important to understand the role of sustaining and reinforcement we hope tissue integration of the mesh will play. We can thus adapt procedures to have the best kinetics and maximal resistance of montages. Study of the kinetics and maximal plateau allows us to make the best clinical recommendations.

Square not a running knot.

BACKGROUND: The tensile strength of running monofilament polypropylene sutures anchored with square knots was compared with the strength of the same size sutures anchored with half hitches. STUDY DESIGN: Polypropylene (Prolene; Ethicon) 0, 2-0, 3-0, 4-0, and 5-0 sutures were secured to a tensionometer with either square knots or half hitches. As tension was applied to the running suture end, the force required to break the suture and the point at which the break occurred were recorded. RESULTS: The sutures anchored with square knots showed only 75% of the strength of the sutures secured with half hitches (p=<0.001). Every suture tied with square knots broke precisely at the point where the last two squared throws invariably tumbled into half hitches with increased tension on the running end. The resulting stress transformation distorted and weakened the suture, as documented by electron microscopy scanning. The sutures secured with half hitches did not show any surface defects, and none of the running sutures tied down with half hitches broke at the knots. CONCLUSIONS: A running polypropylene suture initially anchored with half hitches is stronger and safer than a running suture tied down with square knots.

Qual embalagem você tem usado para autoclavar os seus materiais? / What package are you using for material steam sterilization purpose?

O presente artigo apresenta o uso da embalagem industrial de polipropileno, de gramatura 80g/m², para esterilização de materiais em autoclave. São apresentados os testes laboratoriais piloto comprovando sua eficácia. Diante do seu baixo custo e ótima apresentação, recomendamos o seu uso como alternativa ao grau cirúrgico e ao papel kraft.

Characterization of the structure and properties of authentic and counterfeit polypropylene surgical meshes.

A counterfeit version of the Ethicon Prolene polypropylene mesh was distributed to hospitals and clinics and unintentionally implanted into patients undergoing tension-free hernia repair. On December 19, 2003, the Food and Drug Administration (FDA) issued a public health web notification indicating that the counterfeit mesh was not sterile or safe to use. To develop safety recommendations for patients with the counterfeit mesh implant, we compared the counterfeit's structural, physical, chemical and mechanical properties with polypropylene meshes previously cleared by FDA. The mesh fibers for all the products tested were found to have similar chemical and physical properties. The mechanical properties were directly related to the knitted structure (loop size, repeat distance, fabric tightness) and the porosity. Extracts from the counterfeit mesh passed cytotoxicity screening tests. The FDA further recommended that if the mesh had been inadvertently implanted, then those patients should be monitored as would be the practice for any patient with an implanted surgical mesh.

Collagen deposition around polypropylene tapes implanted in the rectus fascia of female rats.

OBJECTIVE: Implantation of the mesh induces a foreign-body reaction followed by the development of connective tissue that may alter tape property. The aim of our study was to evaluate the deposition of collagen in the vicinity of monofilament tension-free vaginal tape (TVT; Ethicon Inc., Johnson & Johnson) and multifilament intravaginal slingplasty (IVS; Tyco Healthcare) polypropylene tapes implanted in female rats. METHODS: The samples of the meshes (10 mg each) were implanted in the rectus fascia of 14 Wistar female rats and removed after 42 days. Collagen was extracted with 0.5 M acetic acid and subsequently with pepsin (1 mg/ml in 0.5 M acetic acid). Collagen concentration was measured using Sircol Collagen Assay (Biocolor Ltd.) and normalised for milligrams of tape weight. For histological examination, tape samples were stained with haematoxylin and eosin or with silver for type III collagen. RESULTS: The total amount of collagen extracted did not differ significantly between TVT and IVS samples. For both tapes, extraction with acetic acid yielded a higher amount of collagen (about 70%) than extraction with pepsin. On histological examination, less densely packed bundles of collagen fibres and a slightly more intense inflammatory reaction were observed with TVT compared with IVS mesh. CONCLUSION: The total amount of collagen deposited around the polypropylene mesh implanted in female rats was similar for TVT and IVS meshes, but differences were noted in the arrangement of the collagen fibres and the intensity of the inflammatory reaction.

Clinical evaluation of the polypropylene-polyester knit used as a cranioplasty material.

UNLABELLED: The paper presents clinical evaluation of the polypropylene-polyester knit used as a cranioplasty material. MATERIAL: Between year 1980 and 2002 275 cranioplastic procedures using the polypropylene-polyester plates Codubix were carried out in the Department of Neurosurgery of the Medical University of Lódz. There were 146 patients who primarily sustained head injuries and 129 non-traumatic patients with craniectomies carried out for various other reasons. In the majority of cases, i.e. in 158 patients, cranioplasty was performed later than 6 months after the primary surgery. The largest implant measured 430 cm2. RESULTS: Excellent and good outcome was achieved in 92% of the patients whereas the rate of local infection was 8%. CONCLUSIONS: Codubix knitted polypropylene-polyester implant proved to be useful and a safe cranioplastic material.

[Tissue reaction to polypropylene mono-or multi-filament tapes used in surgical techniques of stress urinary incontinence treatment]. / Reakcja tkankowa wokól wszczepionych fragmentów tasmy polipropylenowej: mono-i multifilamentowej stosowanych w leczeniu wysilkowego nietrzymania moczu u kobiet.

OBJECTIVES: The "gold standard" in surgical treatment of stress urinary incontinence (SUI) is sling operation with polypropylene tape appliance under the mid urethra. There are two types of polypropylene tape which are the most popular nowadays. These two tapes are differently knitted so they have different biomechanical features. The TVT tape is monofilament, rarely knitted and highly elastic but the IVS mesh is multifilament, densly knitted and has only little possibility to stretch. The aim of our study was to assess the tissue reaction to the mono-(TVT) and multifilament (IVS) tapes. MATERIAL AND METHODS: The 10 mm x 10 mm pieces of TVT and IVS tapes were implanted inlay the fascia of musculus abdominis rectus of 14 rat females (2 groups of 7 animals). The tapes with the margin of surrounding fascia were taken off after 6 weeks of healing. All samples were fixed in 10% Formaldehyde in phosphate buffered saline and embedded in paraffin. Four micron tissue sections were stained with hematoxylin and eosin, the reticulin silver impregnation stain according to Gomori (for collagen type III) and periodic acid Schiff and alcian blue (for proteoglycan). RESULTS: In all sections filaments visible as elipsoids were surrounded by resorptive granulation with large multinucleated giant cells like around "foreign body". The diameter of monofilaments was about 150 microns. The connective tissue in the vicinity of mesh was rich of inflammatory cells like histiocytes, lymphocytes, a few polymorphonuclear leucocytes as well as adipocytes and fibroblasts. The large multinucleated giant cells adjacent to monofilaments were relatively bigger than these cells around multifilaments. Moreover, this granulation tissue has a lot of new blood vessels and collagenous fibrous tissue. The multifilaments were about 40 microns in diameter. The inflammatory granulation infiltrated aggregates of multifilaments. This tissue had only few inflammatory cells in comparison to tissue around monofilaments. The large multinucleated giant cells apposed to the mesh were small and collagen created thicker, more compacted bundles. CONCLUSION: The multifilament polypropylene tape induces weaker inflammatory tissue reaction than monofilament mesh. The thicker and more compacted collagen bundles are created around multifilaments so the natural tensile strength of the surrounding tissue is probably higher.

[Mechanical properties of biological or synthetic implants used to treat genital prolapse and stress incontinence in women : what is the ideal material?]. / Propriétés mécaniques des implants biologiques ou synthétiques utilisés dans les cures de prolapsus et d'incontinence urinaire de la femme: quel est le matériau idéal?

INTRODUCTION: Many surgical techniques proposed for genital prolapse or stress incontinence use prosthetic material to reinforce native tissues. Most of the synthetic meshes used have been designed for hernia repair. MATERIAL AND METHOD: We study the biomechanical properties of human Alloderm or animals tissues like Pelvicol and of synthetic resorbable and permanent meshes. We report the results from the literature. We report the results of a personal study of the biomechanical properties of synthetic meshes. RESULTS: The literature on biomechanical properties of biological or synthetic meshes and their evolution after implantation is sparse. Biogyn ITY or Prolène are the only meshes without spatial orientation. Their resistance to rupture and mechanical properties are variable and seem poor for Biogyn W8 et Mersuture. DISCUSSION: Reviewing the literature we discuss the ideal properties for synthetic meshes used for cure of genital prolapse.

In vitro study of Human Dermal Fibroblasts seeded on two kinds of surgical meshes: monofilamented Polypropylene and multifilamented Polyestere.

Many different synthetic biomaterials have been recently proposed in the majority of the techniques for hernioplasty and pelvic floor surgery. Required qualities of an implantable prosthetic material have been well established in the past and today the biomaterials better performing to this purpose are the monofilamented Polypropylene (Marlex) and the multifilamented Polyestere (Mersilene). But, in spite of a wide surgical use of these two kinds of meshes, many failures of these implantations are reported leading to removal of the prosthetic implanted material. If some of these failures are due to errors in surgical technique, others seem to be due to inadequacy of the selected material, too much soft or too much stiff, or too much or too little incorporated into the host tissue. This experiment investigated the different behaviour of in vitro cultured Human Dermal Fibroblasts, seeded on specimens of both meshes and then observed by Light (LM) and Scanning Electron Microscopy (SEM). Around the multifilamented threads of Polyestere mesh, fibroblasts could grow very well, filling the holes and making a continous cell layer completely envelopping the mesh. At the same culture time, around the Polypropylene mesh only big groups of fibroblasts were evident at the thread interlacing points. Therefore, it could be concluded that both meshes stimulate good fibroblast attachment and proliferation but in a very different way and amount; it will be up to the surgeon to select the appropriate mesh according to the specific surgical purpose.