The inhibitory effect of a Lactobacillus acidophilus derived biosurfactant on biofilm producer Serratia marcescens

PubMed Central

Shokouhfard, Maliheh; Kermanshahi, Rouha Kasra; Shahandashti, Roya Vahedi; Feizabadi, Mohammad Mehdi; Teimourian, Shahram

2015-01-01

Objective(s): Serratia marcescens is one of the nosocomial pathogen with the ability to form biofilm which is an important feature in the pathogenesis of S. marcescens. The aim of this study was to determine the anti-adhesive properties of a biosurfactant isolated from Lactobacillus acidophilus ATCC 4356, on S. marcescens strains. Materials and Methods: Lactobacillus acidophilus ATCC 4356 was selected as a probiotic strain for biosurfactant production. Anti-adhesive activities was determined by pre-coating and co- incubating methods in 96-well culture plates. Results: The FTIR analysis of derived biosurfactant revealed the composition as protein component. Due to the release of such biosurfactants, L. acidophilus was able to interfere with the adhesion and biofilm formation of the S. marcescens strains. In co-incubation method, this biosurfactant in 2.5 mg/ml concentration showed anti-adhesive activity against all tested strains of S. marcescens (P<0.05). Conclusion: Our results show that the anti-adhesive properties of L. acidophilus biosurfactant has the potential to be used against microorganisms responsible for infections in the urinary, vaginal and gastrointestinal tracts, as well as skin, making it a suitable alternative to conventional antibiotics. PMID:26730335

Novel amphiphilic poly(dimethylsiloxane) based polyurethane networks tethered with carboxybetaine and their combined antibacterial and anti-adhesive property

NASA Astrophysics Data System (ADS)

Jiang, Jingxian; Fu, Yuchen; Zhang, Qinghua; Zhan, Xiaoli; Chen, Fengqiu

2017-08-01

The traditional nonfouling materials are powerless against bacterial cells attachment, while the hydrophobic bactericidal surfaces always suffer from nonspecific protein adsorption and dead bacterial cells accumulation. Here, amphiphilic polyurethane (PU) networks modified with poly(dimethylsiloxane) (PDMS) and cationic carboxybetaine diol through simple crosslinking reaction were developed, which had an antibacterial efficiency of 97.7%. Thereafter, the hydrolysis of carboxybetaine ester into zwitterionic groups brought about anti-adhesive properties against bacteria and proteins. The surface chemical composition and wettability performance of the PU network surfaces were investigated by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and contact angle analysis. The surface distribution of PDMS and zwitterionic segments produced an obvious amphiphilic heterogeneous surface, which was demonstrated by atomic force microscopy (AFM). Enzyme-linked immunosorbent assays (ELISA) were used to test the nonspecific protein adsorption behaviors. With the advantages of the transition from excellent bactericidal performance to anti-adhesion and the combination of fouling resistance and fouling release property, the designed PDMS-based amphiphilic PU network shows great application potential in biomedical devices and marine facilities.

Antimicrobial and antibiofilm potential of biosurfactants isolated from lactobacilli against multi-drug-resistant pathogens

PubMed Central

2014-01-01

Background Biosurfactants (BS) are amphiphilic compounds produced by microbes, either on the cell surface or secreted extracellularly. BS exhibit strong antimicrobial and anti-adhesive properties, making them good candidates for applications used to combat infections. In this study, our goal was to assess the in vitro antimicrobial, anti-adhesive and anti-biofilm abilities of BS produced by Lactobacillus jensenii and Lactobacillus rhamnosus against clinical Multidrug Resistant (MDR) strains of Acinetobacter baumannii, Escherichia coli, and Staphylococcus aureus (MRSA). Cell-bound BS from both L. jensenii and L. rhamnosus were extracted and isolated. The surface activities of crude BS samples were evaluated using an oil spreading assay. The antimicrobial, anti-adhesive and anti-biofilm activities of both BS against the above mentioned MDR pathogens were determined. Results Surface activities for both BS ranged from 6.25 to 25 mg/ml with clear zones observed between 7 and 11 cm. BS of both L. jensenii and L. rhamnosus showed antimicrobial activities against A. baumannii, E. coli and S. aureus at 25-50 mg/ml. Anti-adhesive and anti-biofilm activities were also observed for the aforementioned pathogens between 25 and 50 mg/ml. Finally, analysis by electron microscope indicated that the BS caused membrane damage for A. baumannii and pronounced cell wall damage in S. aureus. Conclusion Our results indicate that BS isolated from two Lactobacilli strains has antibacterial properties against MDR strains of A. baumannii, E. coli and MRSA. Both BS also displayed anti-adhesive and anti-biofilm abilities against A. baumannii, E. coli and S. aureus. Together, these capabilities may open up possibilities for BS as an alternative therapeutic approach for the prevention and/or treatment of hospital-acquired infections. PMID:25124936

Nano-graphene oxide incorporated into PMMA resin to prevent microbial adhesion.

PubMed

Lee, Jung-Hwan; Jo, Jeong-Ki; Kim, Dong-Ae; Patel, Kapil Dev; Kim, Hae-Won; Lee, Hae-Hyoung

2018-04-01

Although polymethyl methacrylate (PMMA) is widely used as a dental material, a major challenge of using this substance is its poor antimicrobial (anti-adhesion) effects, which increase oral infections. Here, graphene-oxide nanosheets (nGO) were incorporated into PMMA to introduce sustained antimicrobial-adhesive effects by increasing the hydrophilicity of PMMA. After characterizing nGO and nGO-incorporated PMMA (up to 2wt%) in terms of morphology and surface characteristics, 3-point flexural strength and hardness were evaluated. The anti-adhesive effects were determined for 4 different microbial species with experimental specimens and the underlying anti-adhesive mechanism was investigated by a non-thermal oxygen plasma treatment. Sustained antimicrobial-adhesive effects were characterized with incubation in artificial saliva for up to 28 days. The typical nanosheet morphology was observed for nGO. Incorporating nGO into PMMA roughened its surface and increased its hydrophilicity without compromising flexural strength or surface hardness. An anti-adhesive effect after 1h of exposure to microbial species in artificial saliva was observed in nGO-incorporated specimens, which accelerated with increasing levels of nGO without significant cytotoxicity to oral keratinocytes. Plasma treatment of native PMMA demonstrated that the antimicrobial-adhesive effects of nGO incorporation were at least partially due to increased hydrophilicity, not changes in the surface roughness. A sustained antimicrobial-adhesive property against Candida albicans was observed in 2% nGO for up to 28 days. The presence of sustained anti-adhesion properties in nGO-incorporated PMMA without loading any antimicrobial drugs suggests the potential usefulness of this compound as a promising antimicrobial dental material for dentures, orthodontic devices and provisional restorative materials. Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Antiadhesive Character of Mucin O-glycans at the Apical Surface of Corneal Epithelial Cells

PubMed Central

Sumiyoshi, Mika; Ricciuto, Jessica; Tisdale, Ann; Gipson, Ilene K.; Mantelli, Flavio; Argüeso, Pablo

2008-01-01

Purpose Prolonged contact of opposite mucosal surfaces, which occurs on the ocular surface, oral cavity, reproductive tract, and gut, requires a specialized apical cell surface that prevents adhesion. The purpose of this study was to evaluate the contribution of mucin O-glycans to the antiadhesive character of human corneal–limbal epithelial (HCLE) cells. Methods Mucin O-glycan biosynthesis in HCLE cells was disrupted by metabolic interference with benzyl-α-GalNAc. The cell surface mucin MUC16 and its carbohydrate epitope H185 were detected by immunofluorescence and Western blot. HCLE cell surface features were assessed by field emission scanning electron microscopy. Cell–cell adhesion assays were performed under static conditions and in a parallel plate laminar flow chamber. Results Benzyl-α-GalNAc disrupted the biosynthesis of O-glycans without affecting apomucin biosynthesis or cell surface morphology. Static adhesion assays showed that the apical surface of differentiated HCLE cells expressing MUC16 and H185 was more antiadhesive than undifferentiated HCLE cells, which lacked MUC16. Abrogation of mucin O-glycosylation in differentiated cultures with benzyl-α-GalNAc resulted in increased adhesion of applied corneal epithelial cells and corneal fibroblasts. The antiadhesive effect of mucin O-glycans was further demonstrated by fluorescence video microscopy in dynamic flow adhesion assays. Cationized ferritin labeling of the cell surface indicated that anionic repulsion did not contribute to the antiadhesive character of the apical surface. Conclusions These results indicate that epithelial O-glycans contribute to the antiadhesive properties of cell surface–associated mucins in corneal epithelial cells and suggest that alterations in mucin O-glycosylation are involved in the pathology of drying mucosal diseases (e.g., dry eye). PMID:18172093

Evaluation of the durability and antiadhesive action of 2-methacryloyloxyethyl phosphorylcholine grafting on an acrylic resin denture base material.

PubMed

Takahashi, Nana; Iwasa, Fuminori; Inoue, Yuuki; Morisaki, Hirobumi; Ishihara, Kazuhiko; Baba, Kazuyoshi

2014-08-01

The polymer 2-methacryloyloxyethyl phosphorylcholine is currently used on medical devices to prevent infection. Denture plaque-associated infection is regarded as a source of serious dental and medical complications in the elderly population, and denture hygiene, therefore, is an issue of considerable importance for denture wearers. Furthermore, because denture bases are exposed to mechanical stresses, for example, denture brushing, the durability of the coating is important for retaining the antiadhesive function of 2-methacryloyloxyethyl phosphorylcholine. The purpose of this study is to investigate the durability and antiadhesive activity of two 2-methacryloyloxyethyl phosphorylcholine polymer coating techniques: poly-2-methacryloyloxyethyl phosphorylcholine grafting and poly-2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate coating. It was revealed that 2-methacryloyloxyethyl phosphorylcholine polymer coating of the denture base resin polymethyl methacrylate decreases bacterial biofilm formation. Durability was examined by rhodamine staining and elemental surface analysis and by determining the wetting properties of the 2-methacryloyloxyethyl phosphorylcholine polymer-modified polymethyl methacrylate after a friction test that comprised 500 brushing cycles. Antiadhesive activity was examined by using a Streptococcus mutans biofilm formation assay. Poly-2-methacryloyloxyethyl phosphorylcholine-grafted polymethyl methacrylate retained 2-methacryloyloxyethyl phosphorylcholine units and antiadhesive activity even after repetitive mechanical stress, whereas co-n-butyl methacrylate-coated polymethyl methacrylate did not. These results demonstrated that graft polymerization of 2-methacryloyloxyethyl phosphorylcholine on denture surfaces may contribute to the durability of the coating and prevent microbial retention. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Determination of the antibiofilm, antiadhesive, and anti-MRSA activities of seven Salvia species.

PubMed

Al-Bakri, Amal G; Othman, Ghadeer; Afifi, Fatma U

2010-10-01

Several Salvia species are indigenous to Jordan and are widely used as beverages and spices and for their medicinal properties. The objective of the study was to establish the antimicrobial activities, including the antiadhesive and antibiofilm effects of seven different Salvia species. Methods used for planktonic culture included agar diffusion, broth microdilution, and minimal biocidal concentration determination while viable count was used for the determination of the antibiofilm and antiadhesion activities. Overnight cultures of reference strains of Candida albicans, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and clinical strains of methicillin-resistant S. aureus (MRSA) were used as test microorganisms. An antimicrobial activity toward planktonic cultures demonstrated a significant bacteriocidal activity (≥4 log cycle reduction) for the S. triloba extract against S. aureus including MRSA. Its volatile oil exhibited an antimicrobial activity covering all tested microorganisms with the exception of P. aeruginosa. S. triloba extract and volatile oil were successful in preventing and controlling the biofilm, demonstrating antiadhesion and antibiofilm activities, respectively. These reported activities for S. triloba extract and volatile oil allows their listing as potential antibiofilm and anti-MRSA natural agents. This might suggest their use as an antiseptic in the prophylaxis and treatment of S. aureus-associated skin infections. The antimicrobial activity of the other tested Salvia species was negligible.

Flavones in citrus exhibit antiadhesive action on platelets.

PubMed

Robbins, R C

1988-01-01

Two methoxylated flavones isolated from citrus, sinensetin (5 methoxyls) and heptamethoxy flavone (7 methoxyls), were compared in vitro with nobiletin for antiadhesive activity on rat platelets. Nobiletin (a hexamethoxyflavone also isolated from citrus) has been previously shown by several workers to have antiadhesive and antithrombogenic activity. The penta- and heptamethoxylated flavones exhibited anti-adhesive activity similar to that of nobiletin. However, activity did not parallel number of methoxyl groups which appear to indicate some degree of specificity between flavone structure and antiadhesive activity on platelets.

The antimicrobial and antiadhesion activities of micellar solutions of surfactin, CTAB and CPCl with terpinen-4-ol: applications to control oral pathogens.

PubMed

Bucci, Andreia R; Marcelino, Larissa; Mendes, Renata K; Etchegaray, Augusto

2018-06-06

The oral pathogen Streptococcus mutans is involved in tooth decay by a process that initiates with biofilm adhesion and caries development. The presence of other microbes such as Candida albicans may worsen the demineralization process. Since both microbes are virulent to the host and will proliferate under specific host immune deficiencies and systemic diseases, it is important to study antimicrobial substances and their effects on both pathogens. There are several antiseptic agents used to reduce plaque biofilm and its outcome (dental caries and/or periodontal disease). However, some of these have undesired effects. In the current study we investigated the antimicrobial and anti-adhesion properties of micellar solutions of surfactants and the plant natural product terpinen-4-ol (TP). The results revealed an increase in antimicrobial properties of the synthetic surfactants, cetylpyridinium chloride (CPC) and cetyltrimethylammonium bromide (CTAB), when mixed with TP. In addition, although surfactin, a biosurfactant, has little antimicrobial activity, it was demonstrated that it enhanced the effect of TP both as antimicrobial and anti-adhesion compound. Surfactin and the synthetic surfactants promote the antimicrobial activity of TP against S. mutans, the causal agent of tooth decay, suggesting specificity for membrane interactions that may be facilitated by surfactants. This is the first report on the successful use of surfactin in association with TP to inhibit the growth and adhesion of microbial pathogens. Surfactin has other beneficial properties besides being biodegradable, it has antiviral and anti-mycoplasma activities in addition to adjuvant properties and encapsulating capacity at low concentration.

Invited review: Anti-adhesive properties of bovine oligosaccharides and bovine milk fat globule membrane-associated glycoconjugates against bacterial food enteropathogens.

PubMed

Douëllou, T; Montel, M C; Thevenot Sergentet, D

2017-05-01

The prevalence of the main raw milk and raw milk-derived dairy product enteropathogens (Campylobacter, Shiga toxin-producing Escherichia coli, Listeria, and Salmonella) is higher than the number of epidemiological cases related to ingesting these foodstuffs. Bovine milk oligosaccharides and milk fat globule membrane (MFGM)-linked glycoconjugates interact with foodborne enteropathogens to inhibit their adhesion to intestinal cells and tissues. This review examines the main mechanisms and strategies used by enteropathogens to adhere to their target, details the anti-adhesive properties of MFGM against enteropathogens and enterotoxins, assesses the integrity of bacteria-MFGM complexes during dairy product manufacture and digestion, and discusses the potential for using these macromolecules and glycoconjugates in foods for public health. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Determination of the antibiofilm, antiadhesive, and anti-MRSA activities of seven Salvia species

PubMed Central

Al-Bakri, Amal G.; Othman, Ghadeer; Afifi, Fatma U.

2010-01-01

Background: Several Salvia species are indigenous to Jordan and are widely used as beverages and spices and for their medicinal properties. The objective of the study was to establish the antimicrobial activities, including the antiadhesive and antibiofilm effects of seven different Salvia species. Materials and Methods: Methods used for planktonic culture included agar diffusion, broth microdilution, and minimal biocidal concentration determination while viable count was used for the determination of the antibiofilm and antiadhesion activities. Overnight cultures of reference strains of Candida albicans, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and clinical strains of methicillin-resistant S. aureus (MRSA) were used as test microorganisms. Results: An antimicrobial activity toward planktonic cultures demonstrated a significant bacteriocidal activity (≥4 log cycle reduction) for the S. triloba extract against S. aureus including MRSA. Its volatile oil exhibited an antimicrobial activity covering all tested microorganisms with the exception of P. aeruginosa. S. triloba extract and volatile oil were successful in preventing and controlling the biofilm, demonstrating antiadhesion and antibiofilm activities, respectively. Conclusion: These reported activities for S. triloba extract and volatile oil allows their listing as potential antibiofilm and anti-MRSA natural agents. This might suggest their use as an antiseptic in the prophylaxis and treatment of S. aureus-associated skin infections. The antimicrobial activity of the other tested Salvia species was negligible. PMID:21120026

Estimating in vivo airway surface liquid concentration in trials of inhaled antibiotics.

PubMed

Hasan, M A; Lange, C F

2007-01-01

Antibiotic drugs exhibit concentration dependence in their efficacy. Therefore, ensuring appropriate concentration of these drugs in the relevant body fluid is important for obtaining the desired therapeutic and physiological action. Until recently there had been no suitable method available to measure or estimate concentration of drugs in the human airways resulting from inhaled aerosols or to determine the amount of inhaled antibiotics required to ensure minimum inhibitory concentration of a drug in the airway surface liquid (ASL). In this paper a numerical method is used for estimating local concentration of inhaled pharmaceutical aerosols in different generations of the human tracheobronchial airways. The method utilizes a mathematical lung deposition model to estimate amounts of aerosols depositing in different lung generations, and a recent ASL model along with deposition results to assess the concentration of deposited drugs immediately following inhalation. Examples of concentration estimates for two case studies: one for the antibiotic tobramycin against Pseudomonas aeruginosa, and another for taurolidine against Burkholderia cepacia are presented. The aerosol characteristics, breathing pattern and properties of nebulized solutions were adopted from two recent clinical studies on efficacy of these drugs in cystic fibrosis (CF) patients and from other sources in the literature. While the clinically effective tobramycin showed a concentration higher than the required in vivo concentration, that for the ineffective taurolidine was found to be below the speculated required in vivo concentration. Results of this study thus show that the mathematical ASL model combined with the lung deposition model can be an effective tool for helping decide the optimum dosage of inhaled antibiotic drugs delivered during human clinical trials.

Standard Biocompatibility Studies Do Not Predict All Effects of PVA/CMC Anti-Adhesive Gel in vivo.

PubMed

Freytag, Christiane; Odermatt, Erich K

2016-01-01

PVA/CMC (polyvinyl alcohol/carboxymethyl cellulose) hydrogel fulfills various physiochemical properties required for an adhesion barrier and has shown good anti-adhesion properties in previous in vivo studies. In this investigation, we assessed the in vitro and in vivo biocompatibility of PVA/CMC gel and compared this to the functionality and promotion of wound healing for two surgical indications. Standardized ISO10993 in vitro and in vivo biocompatibility studies, comprising cytotoxicity, genotoxicity, acute systemic toxicity, delayed contact and maximization sensitization test, intracutaneous reactivity and local muscle implantation, were performed on PVA/CMC gel. In the functional studies, PVA/CMC gel was applied - on the one hand - to a rabbit abdominal wall model enforced with a polypropylene mesh for testing the anti-adhesion properties and - on the other hand - to an end- to-end anastomosis model that was selected for surveying potential influences of different dosages of PVA/CMC gel on anastomotic wound healing. The ISO10993 methods indicated generally good biocompatibility properties, such as the absence of cytotoxic and mutagenic effects as well as no signs of systemic toxicity and sensitization potentials. No irritation effects were observed after the intracutaneous injection of lipophilic PVA/CMC sesame oil extract. However, the injection of hydrophilic PVA/CMC physiologic saline extract induced slight irritation. Following rabbit muscle implantation of the PVA membrane for 2, 4, 12, 26 and 52 weeks, a slight irritant effect was observed at 12 weeks due to the peak of phagocytosis. In the functionality tests, PVA/CMC gel showed good anti-adhesive effects in the abdominal wall model enforced with the mesh, with significantly lower and less tense adhesions compared to the untreated control. However, moderate signs of inflammation, especially in the spleen were observed after the intra-abdominal implantation of 3.3 ml PVA/CMC gel per kg body weight. In the end-to-end anastomosis model, PVA/CMC gel had no influence on wound healing. For dosages of 1-6 ml gel per treatment, no signs of intestinal leaks were detected, and tensile strength was equal to that of the untreated control, but again more moderate signs of inflammation in the spleen were observed at a dosage >3 ml. Comparing the standardized ISO10993 methods, anti-adhesive PVA/CMC gel displays good biocompatibility. However, those methods do not seem to be sensitive enough because the rabbit abdominal wall and the end-to-end anastomosis models display more effects with respect to the dosage and routes of the intra-abdominal resorption of PVA/CMC gel - with the recommended <2 ml PVA/CMC gel per kg body weight as a secure dosage. © 2016 S. Karger AG, Basel.

Poly(l-glutamic acid)-g-poly(ethylene glycol) external layer in polyelectrolyte multilayer films: Characterization and resistance to serum protein adsorption.

PubMed

Szczepanowicz, Krzysztof; Kruk, Tomasz; Świątek, Wiktoria; Bouzga, Aud M; Simon, Christian R; Warszyński, Piotr

2018-06-01

Formation of protein-resistant surfaces is a major challenge in the design of novel biomaterials and an important strategy to prevent protein adsorption is the formation of protein-resistant coatings. It can be achieved by proper modification of surfaces, e.g., by immobilization of hydrophilic polymers such as poly(ethylene glycol) (PEG). An appropriate method to immobilize PEG at charged surfaces is the adsorption of copolymers with PEG chains grafted onto polyelectrolyte backbone. The growing interest in the use of polyelectrolyte multilayer coatings in biomedical applications to improve biocompatibility and/or to prepare coating with antiadhesive properties has been the main reason for these studies. Therefore the aim was to produce protein resistant polyelectrolyte multilayer films. They were formed via the layer-by-layer approach, while their pegylation by the deposition of pegylated polyanion, PGA-g-PEG, as an external layer. The influence of PEG chain length and grafting density of PGA-g-PEG copolymers on the protein antiadhesive properties of pegylated polyelectrolyte multilayer films was investigated. To monitor the formation of pegylated and non-pegylated multilayer films, adsorption of the following proteins: HSA, Fibrinogen, and FBS were measured by quartz crystal microbalance (QCM - D). We found that protein adsorption onto all pegylated polyelectrolyte multilayers was significantly reduced in comparison to non-pegylated ones. Long-term performance tests confirmed the stability and the durability of the protein resistant properties of the pegylated multilayers. Antiadhesive properties of tested surfaces pegylated by PGA-g-PEG were compared to the available data for pegylated polycation PLL-g-PEG. Copyright © 2018 Elsevier B.V. All rights reserved.

Manuka honey inhibits adhesion and invasion of medically important wound bacteria in vitro.

PubMed

Maddocks, Sarah Elizabeth; Jenkins, Rowena Eleri; Rowlands, Richard Samuel; Purdy, Kevin John; Cooper, Rose Agnes

2013-12-01

To characterize the effect of manuka honey on medically important wound bacteria in vitro, focusing on its antiadhesive properties. Crystal violet biofilm assays, fluorescent microscopy, protein adhesion assay and gentamicin protection assay were used to determine the impact of manuka honey on biofilm formation, human protein binding and adherence to/invasion into human keratinocytes. Manuka honey effectively disrupted and caused extensive cell death in biofilms of Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus pyogenes. Sublethal doses of manuka honey inhibited bacterial adhesion to the fibronectin, fibrinogen and collagen. Manuka honey impaired adhesion of laboratory and clinical isolates of S. aureus, P. aeruginosa and S. pyogenes to human keratinocytes in vitro, and inhibited invasion by S. pyogenes and homogeneous vancomycin intermediate S. aureus. Manuka honey can directly affect bacterial cells embedded in a biofilm and exhibits antiadhesive properties against three common wound pathogens.

Preparation and High-temperature Anti-adhesion Behavior of a Slippery Surface on Stainless Steel.

PubMed

Zhang, Pengfei; Huawei, Chen; Liu, Guang; Zhang, Liwen; Zhang, Deyuan

2018-03-29

Anti-adhesion surfaces with high-temperature resistance have a wide application potential in electrosurgical instruments, engines, and pipelines. A typical anti-wetting superhydrophobic surface easily fails when exposed to a high-temperature liquid. Recently, Nepenthes-inspired slippery surfaces demonstrated a new way to solve the adhesion problem. A lubricant layer on the slippery surface can act as a barrier between the repelled materials and the surface structure. However, the slippery surfaces in previous studies rarely showed high-temperature resistance. Here, we describe a protocol for the preparation of slippery surfaces with high-temperature resistance. A photolithography-assisted method was used to fabricate pillar structures on stainless steel. By functionalizing the surface with saline, a slippery surface was prepared by adding silicone oil. The prepared slippery surface maintained the anti-wetting property for water, even when the surface was heated to 300 °C. Also, the slippery surface exhibited great anti-adhesion effects on soft tissues at high temperatures. This type of slippery surface on stainless steel has applications in medical devices, mechanical equipment, etc.

Fabrication of anti-adhesion surfaces on aluminium substrates of rubber plastic moulds using electrolysis plasma treatment

NASA Astrophysics Data System (ADS)

Meng, Jianbing; Dong, Xiaojuan; Wei, Xiuting; Yin, Zhanmin

2015-04-01

An anti-adhesion surface with a water contact angle of 167° was fabricated on aluminium samples of rubber plastic moulds by electrolysis plasma treatment using mixed electrolytes of C6H5O7(NH4)3 and Na2SO4, followed by fluorination. To optimise the fabrication conditions, several important processing parameters such as the discharge voltage, discharge time, concentrations of supporting electrolyte and stearic acid ethanol solution were examined systematically. Using scanning electron microscopy (SEM) to analyse surfaces morphology, micrometer scale pits, and protrusions were found on the surface, with numerous nanometer mastoids contained in the protrusions. These binary micro/nano-scale structures, which are similar to the micro-structures of soil-burrowing animals, play a critical role in achieving low adhesion properties. Otherwise, the anti-adhesion behaviours of the resulting samples were analysed by the atomic force microscope (AFM), Fourier-transform infrared spectrophotometer (FTIR), electrons probe micro-analyzer (EPMA), optical contact angle meter, digital Vickers microhardness (Hv) tester, and electronic universal testing. The results show that the electrolysis plasma treatment does not require complex processing parameters, using a simple device, and is an environment-friendly and effective method. Under the optimised conditions, the contact angle (CA) for the modified anti-adhesion surface is up to 167°, the sliding angle (SA) is less than 2°, roughness of the sample surface is only 0.409μm. Moreover, the adhesion force and Hv are 0. 9KN and 385, respectively.

Polysaccharide-based antibiofilm surfaces.

PubMed

Junter, Guy-Alain; Thébault, Pascal; Lebrun, Laurent

2016-01-01

Surface treatment by natural or modified polysaccharide polymers is a promising means to fight against implant-associated biofilm infections. The present review focuses on polysaccharide-based coatings that have been proposed over the last ten years to impede biofilm formation on material surfaces exposed to bacterial contamination. Anti-adhesive and bactericidal coatings are considered. Besides classical hydrophilic coatings based on hyaluronic acid and heparin, the promising anti-adhesive properties of the algal polysaccharide ulvan are underlined. Surface functionalization by antimicrobial chitosan and derivatives is extensively surveyed, in particular chitosan association with other polysaccharides in layer-by-layer assemblies to form both anti-adhesive and bactericidal coatings. Bacterial contamination of surfaces, leading to biofilm formation, is a major problem in fields as diverse as medicine, first, but also food and cosmetics. Many prophylactic strategies have emerged to try to eliminate or reduce bacterial adhesion and biofilm formation on surfaces of materials exposed to bacterial contamination, in particular implant materials. Polysaccharides are widely distributed in nature. A number of these natural polymers display antibiofilm properties. Hence, surface treatment by natural or modified polysaccharides is a promising means to fight against implant-associated biofilm infections. The present manuscript is an in-depth look at polysaccharide-based antibiofilm surfaces that have been proposed over the last ten years. This review, which is a novelty compared to published literature, will bring well documented and updated information to readers of Acta Biomaterialia. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Fabrication of anti-adhesion surfaces on aluminium substrates of rubber plastic moulds using electrolysis plasma treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meng, Jianbing, E-mail: jianbingmeng@126.com; Dong, Xiaojuan; Wei, Xiuting

An anti-adhesion surface with a water contact angle of 167° was fabricated on aluminium samples of rubber plastic moulds by electrolysis plasma treatment using mixed electrolytes of C{sub 6}H{sub 5}O{sub 7}(NH{sub 4}){sub 3} and Na{sub 2}SO{sub 4}, followed by fluorination. To optimise the fabrication conditions, several important processing parameters such as the discharge voltage, discharge time, concentrations of supporting electrolyte and stearic acid ethanol solution were examined systematically. Using scanning electron microscopy (SEM) to analyse surfaces morphology, micrometer scale pits, and protrusions were found on the surface, with numerous nanometer mastoids contained in the protrusions. These binary micro/nano-scale structures, whichmore » are similar to the micro-structures of soil-burrowing animals, play a critical role in achieving low adhesion properties. Otherwise, the anti-adhesion behaviours of the resulting samples were analysed by the atomic force microscope (AFM), Fourier-transform infrared spectrophotometer (FTIR), electrons probe micro-analyzer (EPMA), optical contact angle meter, digital Vickers microhardness (Hv) tester, and electronic universal testing. The results show that the electrolysis plasma treatment does not require complex processing parameters, using a simple device, and is an environment-friendly and effective method. Under the optimised conditions, the contact angle (CA) for the modified anti-adhesion surface is up to 167°, the sliding angle (SA) is less than 2°, roughness of the sample surface is only 0.409μm. Moreover, the adhesion force and H{sub v} are 0. 9KN and 385, respectively.« less

Anti-adhesive effects of a newly developed two-layered gelatin sheet in dogs.

PubMed

Torii, Hiroko; Takagi, Toshitaka; Urabe, Mamoru; Tsujimoto, Hiroyuki; Ozamoto, Yuki; Miyamoto, Hiroe; Ikada, Yoshihito; Hagiwara, Akeo

2017-08-01

Adhesion after pelvic surgery causes infertility, ectopic pregnancy, and ileus or abdominal pain. The materials currently available for clinical use are insufficient. The purpose of this study was to develop an anti-adhesive material that overcomes the limitations of conventional anti-adhesive agents. The adhesion prevention effects of three methods - a two-layered sheet composed of gelatin film and gelatin sponge, Seprafilm and INTERCEED - were evaluated in 37 dogs. Anti-adhesive effects were investigated macroscopically and microscopically in a cauterized uterus adhesion model. Cell growth on the materials in vitro using human peritoneal mesothelial cells, fibroblasts and uterine smooth muscle cells were also evaluated. The two-layered gelatin sheet had significantly superior anti-adhesive effects compared to the conventional materials (Seprafilm and INTERCEED). A single-cell layer of mature mesothelium formed three weeks after surgery in the gelatin group. Peritoneum regeneration in the Seprafilm and INTERCEED groups was delayed and incomplete in the early phase. Little inflammation around the materials occurred and cell growth was significantly proliferated with the gelatin sheet. The anti-adhesive effects of a two-layered gelatin sheet were superior to conventional agents in a cauterized canine uterus model, demonstrating early regeneration of the peritoneum, little inflammation and material endurance. The newly developed two-layered gelatin sheet is a useful option as an anti-adhesive agent for deeply injured and hemorrhagic sites. © 2017 The Authors. Journal of Obstetrics and Gynaecology Research published by John Wiley & Sons Australia, Ltd on behalf of Japan Society of Obstetrics and Gynecology.

In vitro and in vivo degradation of potential anti-adhesion materials: Electrospun membranes of poly(ester-amide) based on l-phenylalanine and p-(dioxanone).

PubMed

Wang, Bing; Dong, Jun; Niu, Lijing; Chen, Wenyan; Chen, Dongliang; Shen, Chengyi; Zhu, Jiang; Zhang, Xiaoming

2017-08-01

Electrospun membranes of poly(p-dioxanone-co-l-phenylalanine) (PDPA) hold potential as an anti-adhesion material. Since adjustable degradation properties are important for anti-adhesion materials, in this study, the in vitro and in vivo degradation processes of PDPA electrospun membranes were investigated in detail. The morphological analysis of these membranes revealed the main degradation conditions of PDPA membranes. The weight remaining and molecular weight variation showed that the overall degradation rate of the membranes could be adjusted by modulating the molecular structure of the PDPAs. Especially, α-chymotrypsin could catalyze the degradation process of PDPAs. Based on these results, the in vitro degradation mechanism was demonstrated, and confirmed by 1 H NMR of the hydrolysis products. Finally, the in vivo degradation and biocompatibility of different PDPAs were investigated. The kinetic study showed that the in vitro and in vivo molecular weight loss of PDPAs have the first-order characteristics. The in vivo degradation rate of the most Phe-containing PDPA-3 is the slowest, and this result relates to the biocompatibilities of PDPAs. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1369-1378, 2017. © 2016 Wiley Periodicals, Inc.

Protective potential of non-dialyzable material fraction of cranberry juice on the virulence of P. gingivalis and F. nucleatum mixed infection.

PubMed

Polak, David; Naddaf, Raja; Shapira, Lior; Weiss, Ervin I; Houri-Haddad, Yael

2013-07-01

Periodontitis is a polymicrobial infectious disease. A novel potential chemical treatment modality may lie in bacterial anti-adhesive materials, such as cranberry juice fractions. The aim of this study is to explore the effect of high molecular weight cranberry constituent (non-dialyzable material [NDM]) on the virulence of a mixed infection with Porphyromonas gingivalis and Fusobacterium nucleatum in mice. In vitro, the anti-adhesive property of NDM was validated on epithelial cell culture, and inhibition of coaggregation was tested using a coaggregation assay. The in vivo effect was tested on the outcome of experimental periodontitis induced by a P. gingivalis and F. nucleatum mixed infection, and also on the local host response using the subcutaneous chamber model of infection. Phagocytosis was also tested on RAW macrophages by the use of fluorescent-labeled bacteria. NDM was found to inhibit the adhesion of both species of bacteria onto epithelial cells and to inhibit coaggregation in a dose-dependent manner. NDM consumption by mice attenuated the severity of experimental periodontitis compared with a mixed infection without NDM treatment. In infected subcutaneous chambers, NDM alone reduced tumor necrosis factor-α (TNF-α) levels induced by the mixed infection. In vitro, NDM eliminated TNF-α expression by macrophages that were exposed to P. gingivalis and F. nucleatum, without impairing their viability. Furthermore, NDM increased the phagocytosis of P. gingivalis. The results indicate that the use of NDM may hold potential protective and/or preventive modalities in periodontal disease. Underlying mechanisms for this trait may perhaps be the anti-adhesive properties of NDM or its potential effect on inflammation.

Peritoneal adhesion prevention with a biodegradable and injectable N,O-carboxymethyl chitosan-aldehyde hyaluronic acid hydrogel in a rat repeated-injury model

PubMed Central

Song, Linjiang; Li, Ling; He, Tao; Wang, Ning; Yang, Suleixin; Yang, Xi; Zeng, Yan; Zhang, Wenli; Yang, Li; Wu, Qinjie; Gong, Changyang

2016-01-01

Postoperative peritoneal adhesion is one of the serious issues because it induces severe clinical disorders. In this study, we prepared biodegradable and injectable hydrogel composed of N,O-carboxymethyl chitosan (NOCC) and aldehyde hyaluronic acid (AHA), and assessed its anti-adhesion effect in a rigorous and severe recurrent adhesion model which is closer to clinical conditions. The flexible hydrogel, which gelated in 66 seconds at 37 °C, was cross-linked by the schiff base derived from the amino groups of NOCC and aldehyde groups in AHA. In vitro cytotoxicity test showed the hydrogel was non-toxic. In vitro and in vivo degradation examinations demonstrated the biodegradable and biocompatibility properties of the hydrogel. The hydrogel discs could prevent the invasion of fibroblasts, whereas fibroblasts encapsulated in the porous 3-dimensional hydrogels could grow and proliferate well. Furthermore, the hydrogel was applied to evaluate the anti-adhesion efficacy in a more rigorous recurrent adhesion model. Compared with normal saline group and commercial hyaluronic acid (HA) hydrogel, the NOCC-AHA hydrogel exhibited significant reduction of peritoneal adhesion. Compared to control group, the blood and abdominal lavage level of tPA was increased in NOCC-AHA hydrogel group. These findings suggested that NOCC-AHA hydrogel had a great potential to serve as an anti-adhesion candidate. PMID:27869192

Dynamic surface tension measurement for the screening of biosurfactants produced by Lactobacillus plantarum subsp. plantarum PTCC 1896.

PubMed

Bakhshi, Nafiseh; Soleimanian-Zad, Sabihe; Sheikh-Zeinoddin, Mahmoud

2017-06-01

Currently, screening of microbial biosurfactants (BSs) is based on their equilibrium surface tension values obtained using static surface tension measurement. However, a good surfactant should not only have a low equilibrium surface tension, but its dynamic surface tension (DST) should also decrease rapidly with time. In this study, screening of BSs produced by Lactobacillus plantarum subsp. plantarum PTCC 1896 (probiotic) was performed based on their DST values measured by Wilhelmy plate tensiometry. The relationship between DST and structural and functional properties (anti-adhesive activity) of the BSs was investigated. The results showed that the changes in the yield, productivity and structure of the BSs were growth medium and incubation time dependent (p<0.05). Structurally different BSs produced exhibited identical equilibrium surface tension values. However, differences among the structure/yield of the BSs were observed through the measurement of their DST. The considerable dependence of DST on the concentration and composition of the BS proteins was observed (p<0.05). Moreover, the anti-adhesive activity of the BS was found to be positively correlated with its DST. The results suggest that the DST measurement could serve as an efficient method for the clever screening of BSs producer/production condition, and consequently, for the investigation of probiotic features of bacteria, since the anti-adhesive activity is an important criterion of probiotics. Copyright © 2017 Elsevier Inc. All rights reserved.

Peritoneal adhesion prevention with a biodegradable and injectable N,O-carboxymethyl chitosan-aldehyde hyaluronic acid hydrogel in a rat repeated-injury model

NASA Astrophysics Data System (ADS)

Song, Linjiang; Li, Ling; He, Tao; Wang, Ning; Yang, Suleixin; Yang, Xi; Zeng, Yan; Zhang, Wenli; Yang, Li; Wu, Qinjie; Gong, Changyang

2016-11-01

Postoperative peritoneal adhesion is one of the serious issues because it induces severe clinical disorders. In this study, we prepared biodegradable and injectable hydrogel composed of N,O-carboxymethyl chitosan (NOCC) and aldehyde hyaluronic acid (AHA), and assessed its anti-adhesion effect in a rigorous and severe recurrent adhesion model which is closer to clinical conditions. The flexible hydrogel, which gelated in 66 seconds at 37 °C, was cross-linked by the schiff base derived from the amino groups of NOCC and aldehyde groups in AHA. In vitro cytotoxicity test showed the hydrogel was non-toxic. In vitro and in vivo degradation examinations demonstrated the biodegradable and biocompatibility properties of the hydrogel. The hydrogel discs could prevent the invasion of fibroblasts, whereas fibroblasts encapsulated in the porous 3-dimensional hydrogels could grow and proliferate well. Furthermore, the hydrogel was applied to evaluate the anti-adhesion efficacy in a more rigorous recurrent adhesion model. Compared with normal saline group and commercial hyaluronic acid (HA) hydrogel, the NOCC-AHA hydrogel exhibited significant reduction of peritoneal adhesion. Compared to control group, the blood and abdominal lavage level of tPA was increased in NOCC-AHA hydrogel group. These findings suggested that NOCC-AHA hydrogel had a great potential to serve as an anti-adhesion candidate.

Promising results of cranberry in the prevention of oral Candida biofilms.

PubMed

Girardot, Marion; Guerineau, Amandine; Boudesocque, Leslie; Costa, Damien; Bazinet, Laurent; Enguehard-Gueiffier, Cécile; Imbert, Christine

2014-04-01

In the context of dental caries prevention by natural foodstuff sources, antifungal and antibiofilm activities of dry commercial extracts of cranberry fruit (Vaccinium macrocarpon Aiton) and two other red fruits (Vaccinium myrtillus L. and Malpighia punicifolia L.) were assessed on Candida albicans and Candida glabrata yeasts. When added to the culture medium, the cranberry extract displayed a significant anti-adhesion activity against Candida spp. when used at low concentrations. In addition, the pretreatment of surfaces with this extract induced an anti-adhesion activity mainly against C. glabrata yeasts and an antibiofilm activity against C. albicans. This activity was dependent on concentration, species, and strain. A phytochemical investigation bioguided by anti-adhesion tests against the two Candida species was carried out on crude cranberry juice to determine the active fractions. Three subfractions enriched in proanthocyanidins showed an anti-adhesion activity at low concentrations. This study investigated for the first time the interest of crude extracts of cranberry and cranberry juice fractions to prevent biofilms of C. glabrata. It highlighted the potency of consuming this fruit and using it as a source of anti-adhesion agents. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Comparison of the Anti-Adhesion Activity of Three Different Cranberry Extracts on Uropathogenic P-fimbriated Escherichia coli: a Randomized, Double-blind, Placebo Controlled, Ex Vivo, Acute Study.

PubMed

Howell, Amy; Souza, Dan; Roller, Marc; Fromentin, Emilie

2015-07-01

Research suggests that cranberry (Vaccinium macrocarpon) helps maintain urinary tract health. Bacterial adhesion to the uroepithelium is the initial step in the progression to development of a urinary tract infection. The bacterial anti-adhesion activity of cranberry proanthocyanidins (PACs) has been demonstrated in vitro. Three different cranberry extracts were developed containing a standardized level of 36 mg of PACs. This randomized, double-blind, placebo controlled, ex vivo, acute study was designed to compare the anti-adhesion activity exhibited by human urine following consumption of three different cranberry extracts on uropathogenic P-fimbriated Escherichia coli in healthy men and women. All three cranberry extracts significantly increased anti-adhesion activity in urine. from 6 to 12 hours after intake of a single dose standardized to deliver 36 mg of PACs (as measured by the BL-DMAC method), versus placebo.

Anti-adhesive characteristics of CHF{sub 3}/O{sub 2} and C{sub 4}F{sub 8}/O{sub 2} plasma-modified silicon molds for nanoimprint lithography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Jaemin; Lee, Junmyung; Lee, Hyun Woo

The anti-adhesive characteristics of a plasma-modified silicon mold surface for nanoimprint lithography are presented. Both CHF{sub 3}/O{sub 2} and C{sub 4}F{sub 8}/O{sub 2} plasma were used to form an anti-adhesive layer on silicon mold surfaces. The gas mixing ratios of CHF{sub 3}/O{sub 2} and C{sub 4}F{sub 8}/O{sub 2} were experimentally changed between 0% and 80% to optimize the plasma conditions to obtain a low surface energy of the silicon mold. The plasma characteristics were examined by optical emission spectroscopy (OES). In order to investigate the changes in surface energy and surface chemistry of the anti-adhesive layer during repeated demolding cycles,more » contact angle measurements and X-ray photoelectron spectroscopy (XPS) were performed on the plasma-modified silicon mold surface. Simultaneously, the surface morphology of the demolded resists was evaluated by field-emission scanning electron microscope (FE-SEM) in order to examine the effect of the anti-adhesive layers on the duplicated patterns of the resists. It was observed that the anti-adhesive layer formed by CHF{sub 3}/O{sub 2} plasma treatment was worn out more easily during repeated demolding cycles than the film formed by C{sub 4}F{sub 8}/O{sub 2} plasma treatment, because CHF{sub 3}/O{sub 2} gas plasma formed a thinner plasma-polymerized film over the same plasma treatment time.« less

Influence of anti-adhesive agent on incidence of bile leakage after liver resection: A prospective cohort study.

PubMed

Yu, Young-Dong; Kim, Dong-Sik; Jung, Sung-Won; Han, Jae-Hyun; Suh, Sung-Ock

2016-07-01

Anti-adhesive agents are increasingly used to reduce the incidence of postoperative adhesions following abdominal surgery. Bile leakage after liver resection remains a major cause of postoperative morbidity. The aim of this study was to examine the effect of anti-adhesive agent on bile leakage after liver resection. 77 patients were enrolled to receive an anti-adhesive agent (study group) during liver resection between May 2012 and August 2013. The study group was compared to a match-paired control group. Clinical data were collected including bilirubin concentration in serum and drain fluid and bile leakage rate. In addition, a separate analysis was performed between patients with and without postoperative bile leakage. There was no difference in bile leakage rate or hospital stay between the study group (n = 77) and control group (n = 77). Of the total number of patients (n = 154), there were 29 patients with postoperative bile leak and 125 patients without bile leak. On univariate analysis, patients without history of hepatitis were significantly associated with bile leakage. In addition, liver resection with broader cut surface area was associated with bile leakage. Application of anti-adhesive agent was not associated with bile leakage. On multivariate analysis, resection with broader cut surface area (OR = 2.788, p = 0.026) and patients without history of hepatitis (OR = 5.153, p = 0.039) were significantly associated with bile leakage. Larger area of cut-surface and patients without history of hepatitis were significant risk factors for bile leakage. The use of anti-adhesive agent was not associated with increased risk of bile leakage. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Anti-adhesion Property of the Potential Probiotic Strain Lactobacillus fermentum 8711 Against Methicillin-Resistant Staphylococcus aureus (MRSA).

PubMed

Jayashree, Sathyanarayanan; Karthikeyan, Raman; Nithyalakshmi, Sampath; Ranjani, Jothi; Gunasekaran, Paramasamy; Rajendhran, Jeyaprakash

2018-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug-resistant pathogen and one of the leading causes of nosocomial infection worldwide. Probiotic bacteria play a significant role in preventive or therapeutic interventions of gastrointestinal infections in human as well as animals. In this study, we have investigated the adhesion property of the probiotic strain Lactobacillus fermentum MTCC 8711 and its ability to prevent the adhesion of MRSA to human colon adenocarcinoma cells, Caco-2. We have shown that L. fermentum could efficiently adhere to the Caco-2 cells. Also, we have shown that L. fermentum significantly reduced MRSA adhesion to Caco-2 cells. Three types of experiments were performed to assess the anti-adhesion property of L. fermentum against MRSA. Inhibition (Caco-2 cells were pre-treated with L. fermentum , and subsequently MRSA was added), competition (both L. fermentum and MRSA were added to Caco-2 cells simultaneously), and displacement or exclusion (Caco-2 cells were pre-treated with MRSA, and subsequently L. fermentum was added). In all three experiments, adhesion of MRSA was significantly reduced. Interestingly, L. fermentum could efficiently displace the adhered MRSA, and hence this probiotic can be used for therapeutic applications also. In cytotoxicity assay, we found that L. fermentum per se was not cytotoxic, and also significantly reduced the MRSA-induced cytotoxicity. The protective effect occurred without affecting Caco-2 cell morphology and viability.

Will Parents Participate in and Comply with Programs and Regimens Using Xylitol for Preventing Acute Otitis Media in Their Children?

ERIC Educational Resources Information Center

Danhauer, Jeffrey L.; Johnson, Carole E.; Baker, Jason A.; Ryu, Jung A.; Smith, Rachel A.; Umeda, Claire J.

2015-01-01

Purpose: Antiadhesive properties in xylitol, a natural sugar alcohol, can help prevent acute otitis media (AOM) in children by inhibiting harmful bacteria from colonizing and adhering to oral and nasopharyngeal areas and traveling to the Eustachian tube and middle ear. This study investigated parents' willingness to use and comply with a regimen…

Polysaccharides as Bacterial Antiadhesive Agents and "Smart" Constituents for Improved Drug Delivery Systems Against Helicobacter pylori Infection.

PubMed

Menchicchi, Bianca; Hensel, Andreas; Goycoolea, Francisco M

2015-01-01

The standard eradication treatment of the hostile Helicobacter pylori (H. pylori) stomach infection is facing increasing alarming antibiotic resistance worldwide and calls for alternative strategies to the use of antibiotics. One new perspective in this direction is cytoprotective compounds for targeted prevention of the adhesion of the bacteria to the stomach host cell and to inhibit the bacterial cell-cell communication via quorum sensing by specific inhibitors. Bacterial adhesion of H. pylori to the host cells is mainly mediated by carbohydrate-protein interactions. Therefore, the use of polyvalent carbohydrates, (e.g. plant-derived polysaccharides), as potential antiadhesive compounds, seems to be a promising tool to prevent the initial docking of the bacterium to the stomach cells. Polysaccharides are common constituents of daily food, either as starch or as dietary fiber and often also function as excipients for galenic drug-delivery formulations. In addition, polysaccharides with defined pharmacodynamics action against bacterial outer membrane proteins can have potential as therapeutic tools in the treatment of bacterial infections. Some polysaccharides are known to possess antibacterial properties against gram-positive bacteria, others to inhibit bacterial colonization by blocking specific carbohydrate receptors involved in host-bacteria interaction. This mode of action is advocated as alternative antiadhesion therapy. Ongoing research is also seeking for polysaccharide-based nanoformulations with potential for local drug delivery at the stomach as novel H. pylori therapies. These approaches pose challenges concerned with the stability of the nanomaterials in the harsh conditions of the gastric environment and their capacity to adhere to the stomach mucosa. In a global scenario, geographical diversity and social habits, namely lifestyle and dietary factors, influence the prevalence of the H. pylori-associated diseases and their severity. In this context, the exploration of the biological activity of plant-derived products or polysaccharides commonly present in foods is increasingly becoming more and more attractive. This review aims to present the current state-of-the-art on the antiadhesive capacity of different polysaccharide families, on polysaccharide-based nanosystems and the proof-of-concept evidence of their potential use as alternative medicines against H. pylori.

Antiadhesive Activity and Metabolomics Analysis of Rat Urine after Cranberry (Vaccinium macrocarpon Aiton) Administration.

PubMed

Peron, Gregorio; Pellizzaro, Anna; Brun, Paola; Schievano, Elisabetta; Mammi, Stefano; Sut, Stefania; Castagliuolo, Ignazio; Dall'Acqua, Stefano

2017-07-19

Cranberry (Vaccinium macrocarpon Aiton) is used to treat noncomplicated urinary tract infections (UTIs). A-type procyanidins (PAC-A) are considered the active constituents able to inhibit bacterial adhesion to the urinary epithelium. However, the role of PAC-A in UTIs is debated, because of their poor bioavailability, extensive metabolism, limited knowledge about urinary excretion, and contradictory clinical trials. The effects of 35-day cranberry supplementation (11 mg/kg PAC-A, 4 mg/kg PAC-B) were studied in healthy rats using a ultra performance liquid chromatography-mass spectrometry (UPLC-MS)-based metabolomics approach. Microbial PAC metabolites, such as valeric acid and valerolactone derivatives, were related to cranberry consumption. An increased urinary excretion of glucuronidated metabolites was also observed. In a further experiment, urine samples were collected at 2, 4, 8, and 24 h after cranberry intake and their antiadhesive properties were tested against uropathogenic Escherichia coli. The 8 h samples showed the highest activity. Changes in urinary composition were studied by ultra performance liquid chromatography-time-of-flight (UPLC-QTOF), observing the presence of PAC metabolites. The PAC-A2 levels were measured in all collected samples, and the highest amounts, on the order of ng/mL, were found in the samples collected after 4 h. Results indicate that the antiadhesive activity against uropathogenic bacteria observed after cranberry consumption is ascribable to PAC-A metabolites rather than to a direct PAC-A effect, as the measured PAC-A levels in urine was lower than those reported as active in the literature.

Lidocaine/ketorolac-loaded biodegradable nanofibrous anti-adhesive membranes that offer sustained pain relief for surgical wounds.

PubMed

Kao, Ching-Wei; Lee, Demei; Wu, Min-Hsuan; Chen, Jan-Kan; He, Hong-Lin; Liu, Shih-Jung

2017-01-01

The aim of this study was to develop and evaluate the effectiveness of biodegradable nanofibrous lidocaine/ketorolac-loaded anti-adhesion membranes to sustainably release analgesics on abdominal surgical wounds. The analgesic-eluting membranes with two polymer-to-drug ratios (6:1 and 4:1) were produced via an electrospinning technique. A high-performance liquid chromatography (HPLC) assay was employed to characterize the in vivo and in vitro release behaviors of the pharmaceuticals from the membranes. It was found that all biodegradable anti-adhesion nanofibers released effective concentrations of lidocaine and ketorolac for over 20 days post surgery. In addition, a transverse laparotomy was setup in a rat model for an in vivo assessment of activity of postoperative recovery. No tissue adhesion was observed at 2 weeks post surgery, demonstrating the potential anti-adhesion capability of the drug-eluting nanofibrous membrane. The postoperative activities were recorded for two groups of rats as follows: rats that did not have any membrane implanted (group A) and rats that had the analgesic-eluting membrane implanted (group B). Rats in group B exhibited faster recovery times than those in group A with regard to postoperative activities, confirming the pain relief effectiveness of the lidocaine- and ketorolac-loaded nanofibrous membranes. The experimental results suggested that the anti-adhesion nanofibrous membranes with sustainable elution of lidocaine and ketorolac are adequately effective and durable for the purposes of postoperative pain relief in rats.

Lidocaine/ketorolac-loaded biodegradable nanofibrous anti-adhesive membranes that offer sustained pain relief for surgical wounds

PubMed Central

Kao, Ching-Wei; Lee, Demei; Wu, Min-Hsuan; Chen, Jan-Kan; He, Hong-Lin; Liu, Shih-Jung

2017-01-01

The aim of this study was to develop and evaluate the effectiveness of biodegradable nanofibrous lidocaine/ketorolac-loaded anti-adhesion membranes to sustainably release analgesics on abdominal surgical wounds. The analgesic-eluting membranes with two polymer-to-drug ratios (6:1 and 4:1) were produced via an electrospinning technique. A high-performance liquid chromatography (HPLC) assay was employed to characterize the in vivo and in vitro release behaviors of the pharmaceuticals from the membranes. It was found that all biodegradable anti-adhesion nanofibers released effective concentrations of lidocaine and ketorolac for over 20 days post surgery. In addition, a transverse laparotomy was setup in a rat model for an in vivo assessment of activity of postoperative recovery. No tissue adhesion was observed at 2 weeks post surgery, demonstrating the potential anti-adhesion capability of the drug-eluting nanofibrous membrane. The postoperative activities were recorded for two groups of rats as follows: rats that did not have any membrane implanted (group A) and rats that had the analgesic-eluting membrane implanted (group B). Rats in group B exhibited faster recovery times than those in group A with regard to postoperative activities, confirming the pain relief effectiveness of the lidocaine- and ketorolac-loaded nanofibrous membranes. The experimental results suggested that the anti-adhesion nanofibrous membranes with sustainable elution of lidocaine and ketorolac are adequately effective and durable for the purposes of postoperative pain relief in rats. PMID:28860755

Multi-functional electrospun antibacterial core-shell nanofibrous membranes for prolonged prevention of post-surgical tendon adhesion and inflammation.

PubMed

Shalumon, K T; Sheu, Chialin; Chen, Chih-Hao; Chen, Shih-Heng; Jose, Gils; Kuo, Chang-Yi; Chen, Jyh-Ping

2018-05-01

The possibility of endowing an electrospun anti-adhesive barrier membrane with multi-functionality, such as lubrication, prevention of fibroblast attachment and anti-infection and anti-inflammation properties, is highly desirable for the management of post-surgical tendon adhesion. To this end, we fabricated core-shell nanofibrous membranes (CSNMs) with embedded silver nanoparticles (Ag NPs) in the poly(ethylene glycol) (PEG)/poly(caprolactone) (PCL) shell and hyaluronic acid (HA)/ibuprofen in the core. HA imparted a lubrication effect for smooth tendon gliding and reduced fibroblast attachment, while Ag NPs and ibuprofen functioned as anti-infection and anti-inflammation agents, respectively. CSNMs with a PEG/PCL/Ag shell (PPA) and HA core containing 0% (H/PPA), 10% (HI10/PPA), 30% (HI30/PPA) and 50% (HI50/PPA) ibuprofen were fabricated through co-axial electrospinning and assessed through microscopic, spectroscopic, thermal, mechanical and drug release analyses. Considering nutrient passage through the barrier, the microporous CSNMs exerted the same barrier effect but drastically increased the mass transfer coefficients of bovine serum albumin compared with the commercial anti-adhesive membrane SurgiWrap®. Cell attachment/focal adhesion formation of fibroblasts revealed effective reduction of initial cell attachment on the CSNM surface with minimum cytotoxicity (except HI50/PPA). The anti-bacterial effect against both Gram-negative and Gram-positive bacteria was verified to be due to the Ag NPs in the membranes. In vivo studies using H/PPA and HI30/PPA CSNMs and SurgiWrap® in a rabbit flexor tendon rupture model demonstrated the improved efficacy of HI30/PPA CSNMs in reducing inflammation and tendon adhesion formation based on gross observation, histological analysis and functional assays. We conclude that HI30/PPA CSNMs can act as a multifunctional barrier membrane to prevent peritendinous adhesion after tendon surgery. A multi-functional anti-adhesion barrier membrane that could reduce fibroblasts attachment and penetration while simultaneously prevent post-surgical infection and inflammation is urgently needed. To this end, we prepared electrospun core-shell hyaluronic acid + ibuprofen/polyethylene glycol + polycaprolactone + Ag nanoparticles nanofibrous membranes by co-axial electrospinning as an ideal anti-adhesive membrane. The core-shell structure could meet the need of a desirable anti-adhesion barrier through release of ibuprofen and Ag nanoparticles to reduce infection and inflammation while hyaluronic acid can reduce fibroblasts adhesion. The superior performance of this multi-functional core-shell nanofibrous membrane in preventing peritendinous adhesion and post-surgical inflammation was demonstrated in a rabbit flexor tendon rupture model. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Counterbalancing anti-adhesive effects of Tenascin-C through fibronectin expression in endothelial cells.

PubMed

Radwanska, Agata; Grall, Dominique; Schaub, Sébastien; Divonne, Stéphanie Beghelli-de la Forest; Ciais, Delphine; Rekima, Samah; Rupp, Tristan; Sudaka, Anne; Orend, Gertraud; Van Obberghen-Schilling, Ellen

2017-10-06

Cellular fibronectin (FN) and tenascin-C (TNC) are prominent development- and disease-associated matrix components with pro- and anti-adhesive activity, respectively. Whereas both are present in the tumour vasculature, their functional interplay on vascular endothelial cells remains unclear. We have previously shown that basally-oriented deposition of a FN matrix restricts motility and promotes junctional stability in cultured endothelial cells and that this effect is tightly coupled to expression of FN. Here we report that TNC induces FN expression in endothelial cells. This effect counteracts the potent anti-adhesive activity of TNC and leads to the assembly of a dense highly-branched subendothelial matrix that enhances tubulogenic activity. These findings suggest that pro-angiogenic remodelling of the perivascular matrix may involve TNC-induced upregulation of FN in endothelial cells.

Antiadhesive Properties of Abelmoschus esculentus (Okra) Immature Fruit Extract against Helicobacter pylori Adhesion

PubMed Central

Shevtsova, Anna; Glocker, Erik; Borén, Thomas; Hensel, Andreas

2014-01-01

Background Traditional Asian and African medicine use immature okra fruits (Abelmoschus esculentus) as mucilaginous food to combat gastritis. Its effectiveness is due to polysaccharides that inhibit the adhesion of Helicobacter pylori to stomach tissue. The present study investigates the antiadhesive effect in mechanistic detail. Methodology A standardized aqueous fresh extract (Okra FE) from immature okra fruits was used for a quantitative in vitro adhesion assay with FITC-labled H. pylori J99, 2 clinical isolates, AGS cells, and fluorescence-activated cell sorting. Bacterial adhesins affected by FE were pinpointed using a dot-blot overlay assay with immobilized Lewisb, sialyl-Lewisa, H-1, laminin, and fibronectin. 125I-radiolabeled Okra FE polymer served for binding studies to different H. pylori strains and interaction experiments with BabA and SabA. Iron nanoparticles with different coatings were used to investigate the influence of the charge-dependence of an interaction on the H. pylori surface. Principal findings Okra FE dose-dependently (0.2 to 2 mg/mL) inhibited H. pylori binding to AGS cells. FE inhibited the adhesive binding of membrane proteins BabA, SabA, and HpA to its specific ligands. Radiolabeled compounds from FE bound non-specifically to different strains of H. pylori, as well as to BabA/SabA deficient mutants, indicating an interaction with a still-unknown membrane structure in the vicinity of the adhesins. The binding depended on the charge of the inhibitors. Okra FE did not lead to subsequent feedback regulation or increased expression of adhesins or virulence factors. Conclusion Non-specific interactions between high molecular compounds from okra fruits and the H. pylori surface lead to strong antiadhesive effects. PMID:24416297

Anti-adhesive effect of poloxamer-based thermo-sensitive sol-gel in rabbit laminectomy model.

PubMed

Shin, Sung Joon; Lee, Jae Hyup; So, Jungwon; Min, Kyungdan

2016-11-01

Poloxamer-based thermo-sensitive sol-gel has been developed to reduce the incidence of postoperative scar formation at the laminectomy site. The purpose of this study was to evaluate the anti-adhesive effect of poloxamer based thermo-sensitive sol-gel compared to hyaluronate based solution after laminectomy, using a rabbit model. A thermo-sensitive anti-adhesive with a property of sol-gel transition was manufactured by a physical mixture of Poloxamer188/407, Chitosan and Gelatin. The viscosity in different temperatures was assessed. 72 adult New Zealand rabbits underwent lumbar laminectomy and were randomly divided into experimental (treated with the newly developed agent), positive (treated with hyaluronate based solution), and negative control groups. Each group was subdivided into 1 and 4-week subgroups. Gross and histological evaluations were performed to assess the extent of epidural adhesion. The experimental group showed significantly higher viscosity compared to the positive control group and showed a significant increase of viscosity as the temperature increased. Gross evaluation showed no statistically significant differences between the 1- and 4-week subgroups. However, histologic evaluation showed significant differences both in 1- and 4-week subgroups. Although the 4-week histologic results of the experimental and the positive control subgroups showed no significant difference, both subgroups revealed higher value compared to the negative control subgroup with regard to the ratio of adhesion less than 50 %. The new poloxamer based thermo-sensitive agent showed superior efficacy over the hyaluronate based agent at 1 week postoperatively. At 4 weeks postoperatively, there were no statistically significant differences between the two agents, although both showed efficacy over the sham group.

Antibacterial and tribological behavior of self-assembled monolayer on optical lens

NASA Astrophysics Data System (ADS)

Horng, J. H.; Jeng, Y. R.; Wei, C. C.; Tasi, Y. T.

2010-10-01

This paper studies the effects of the antibacterial and anti-adhesion properties of self-assembled monolayers (SAMs) on optical parts. Therefore, the experiments in this study prepared several kinds of SAMs, including alkyl and biphenyl spacer chains with different surface terminal groups (-CH3,-COOH) and head groups (-SH). This study reports the growth of eight self-assembled monolayers on optical parts: OTS, ODS, OTS with antibacterial solution, ODS with antibacterial solution, and pure antibacterial solution, with bio-compatibility. Experimental results regarding the contact angle of five self-assembled monolayers show that ODS with antibacterial illustrated the maximum contact angle 103° 12 hours after reaction. The solutions of OTS, ODS with antibacterial, OTS with antibacterial, and pure anti-bacterial showed contact angles of 102°, 99°, 101°, and 59° respectively. These results indicate that the antibacterial solution has negligible effects on anti-adhesion property of optical lenses. The results of digital optical microscope system analysis show that in the antibacterial experiment of eight kinds of selfassembled monolayers, the OTSanti50% effect cultured for 24 hours achieved the best results, with a growth rate of 12%. The descending order of antibacterial effect is antibacterial 10%>ODS>OTS> antibacterial 50%>ODSanti50%>OTSanti10%>ODSanti10%. In summary, the surface treatment of optical lenses involving OTSanti 50% is the most capable of effectively increasing antifouling and antibacterial functions.

Bacterial self-defense antibiotics release from organic-inorganic hybrid multilayer films for long-term anti-adhesion and biofilm inhibition properties.

PubMed

Xu, Qingwen; Li, Xi; Jin, Yingying; Sun, Lin; Ding, Xiaoxu; Liang, Lin; Wang, Lei; Nan, Kaihui; Ji, Jian; Chen, Hao; Wang, Bailiang

2017-12-14

Implant-associated bacterial infections pose serious medical and financial issues due to the colonization and proliferation of pathogens on the surface of the implant. The as-prepared traditional antibacterial surfaces can neither resist bacterial adhesion nor inhibit the development of biofilm over the long term. Herein, novel (montmorillonite/poly-l-lysine-gentamicin sulfate) 8 ((MMT/PLL-GS) 8 ) organic-inorganic hybrid multilayer films were developed to combine enzymatic degradation PLL for on-demand self-defense antibiotics release. Small molecule GS was loaded into the multilayer films during self-assembly and the multilayer films showed pH-dependent and linear growth behavior. The chymotrypsin- (CMS) and bacterial infections-responsive film degradation led to the peeling of the films and GS release. Enzyme-responsive GS release exhibited CMS concentration dependence as measured by the size of the inhibition zone and SEM images. Notably, the obtained antibacterial films showed highly efficient bactericidal activity which killed more than 99.9% of S. aureus in 12 h. Even after 3 d of incubation in S. aureus, E. coli or S. epidermidis solutions, the multilayer films exhibited inhibition zones of more than 1.5 mm in size. Both in vitro and in vivo antibacterial tests indicated good cell compatibility, and anti-inflammatory, and long-term bacterial anti-adhesion and biofilm inhibition properties.

Application of a hyaluronic acid gel after intrauterine surgery may improve spontaneous fertility: a randomized controlled trial in New Zealand White rabbits.

PubMed

Huberlant, Stephanie; Fernandez, Herve; Vieille, Pierre; Khrouf, Mohamed; Ulrich, Daniela; deTayrac, Renaud; Letouzey, Vincent

2015-01-01

Intrauterine adhesions (IUAs) are the most common complication after hysteroscopy in patients of reproductive age. Intra-abdominal anti-adhesion gel reduces the incidence of adhesions, but effects on fertility after uterine surgery are not known. The objective of our work was to evaluate the effect of intrauterine anti-adhesion gel on spontaneous fertility after repeated intrauterine surgery with induced experimental synechiae in the rabbit model. Twenty New Zealand White rabbits underwent a double uterine curettage 10 days apart and were randomized into two groups. Each rabbit served as its own control: one uterine tube was the treatment group (A), the second uterine tube was the control group (B) to avoid bias through other causes of infertility. Group A received a post curettage intrauterine instillation of anti-adhesion gel whereas group B, the control group, underwent curettage without instillation of the gel. After a recovery period, the rabbits were mated. An abdominal ultrasound performed 21 days after mating allowed us to diagnose pregnancy and quantify the number of viable fetuses. There was a significant difference in total fetuses in favor of group A, with an average of 3.7 (range, 0-9) total fetuses per tube against 2.1 (0-7) in group B (p = .04). The number of viable fetuses shows a trend in favor of group A, with an average of 3.4 (0-7) viable fetuses per tube against 1.9 (0-6) viable fetuses per tube in group B (p = .05). The use of immediate postoperative anti-adhesion gel improved fertility in an animal model after intrauterine surgery likely to cause uterine synechiae. This experimental model will permit comparison of different anti-adhesion solutions, including assessment of their tolerance and potential mucosal toxicity on embryonic development.

Nanofiber mats composed of a chitosan-poly(d,l-lactic-co-glycolic acid)-poly(ethylene oxide) blend as a postoperative anti-adhesion agent.

PubMed

Ko, Jae Eok; Ko, Young-Gwang; Kim, Won Il; Kwon, Oh Kyoung; Kwon, Oh Hyeong

2017-10-01

Postoperative tissue adhesion causes serious complications and suffering in 90% of patients after peritoneum surgery, while commercial anti-adhesion agents cannot completely prevent postoperative peritoneal adhesions. This study demonstrates electrospining of a blended solution of chitosan, poly(d,l-lactic-co-glycolic acid) (PLGA), and poly(ethylene oxide) (PEO) to fabricate a chitosan-based nanofibrous mat as a postoperative anti-adhesion agent. Rheological studies combined with scanning electron microscopy reveal that the spinnability of the chitosan-PLGA solution could be controlled by adjusting the blend ratio and concentration with average fiber diameter from 634 to 913 nm. Biodegradation of the nanofiber specimens showed accelerated hydrolysis by chitosan. Proliferation of fibroblasts and antimicrobial activity of nanofibers containing chitosan was analyzed. Abdominal defects with cecum adhesion in rats demonstrated that the blend nanofiber mats were effective in preventing tissue adhesion as a barrier (4 weeks after abdominal surgery) by coverage of exfoliated peritoneum and insufficient wound sites at the beginning of the wound healing process. Chitosan-PLGA-PEO blend nanofiber mats will provide a promising key as a postoperative anti-adhesion agent. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1906-1915, 2017. © 2016 Wiley Periodicals, Inc.

Nanopatterning of steel by one-step anodization for anti-adhesion of bacteria.

PubMed

Chen, Shiqiang; Li, Yuan; Cheng, Y Frank

2017-07-13

Surface nanopatterning of metals has been an effective technique for improved performance and functionalization. However, it is of great challenge to fabricate nanostructure on carbon steels despite their extensive use and urgent needs to maintain the performance reliability and durability. Here, we report a one-step anodization technique to nanopattern a carbon steel in 50 wt.% NaOH solution for highly effective anti-adhesion by sulphate reducing bacteria (SRB), i.e., Desulfovibrio desulfuricans subsp. desulfuricans (Beijerinck) Kluyver and van Niel. We characterize the morphology, structure, composition, and surface roughness of the nanostructured film formed on the steel as a function of anodizing potential. We quantify the surface hydrophobicity by contact angle measurements, and the SRB adhesion by fluorescent analysis. The optimal anodization potential of 2.0 V is determined for the best performance of anti-adhesion of SRB to the steel, resulting in a 23.5 times of reduction of SRB adhesion compared to bare steel. We discuss the mechanisms for the film formation on the steel during anodization, and the high-performance anti-adhesion of bacteria to nanopatterned steels. Our technique is simple, cost-effective and environment-friendly, providing a promising alternative for industry-scale surface nanopatterning of carbon steels for effective controlling of bacterial adhesion.

Glycan-functionalized diamond nanoparticles as potent E. coli anti-adhesives.

PubMed

Barras, Alexandre; Martin, Fernando Ariel; Bande, Omprakash; Baumann, Jean-Sébastien; Ghigo, Jean-Marc; Boukherroub, Rabah; Beloin, Christophe; Siriwardena, Aloysius; Szunerits, Sabine

2013-03-21

Bacterial attachment and subsequent biofilm formation on biotic surfaces or medical devices is an increasing source of infections in clinical settings. A large proportion of these biofilm-related infections are caused by Escherichia coli, a major nosocomial pathogen, in which the major adhesion factor is the FimH adhesin located at the tip of type 1 fimbriae. Inhibition of FimH-mediated adhesion has been identified as an efficient antibiotic-alternative strategy to potentially reduce E. coli-related infections. In this article we demonstrate that nanodiamond particles, covently modified with mannose moieties by a "click" chemistry approach, are able to efficiently inhibit E. coli type 1 fimbriae-mediated adhesion to eukaryotic cells with relative inhibitory potency (RIP) of as high as 9259 (bladder cell adhesion assay), which is unprecedented when compared with RIP values previously reported for alternate multivalent mannose-functionalized nanostructures designed to inhibit E. coli adhesion. Also remarkable is that these novel mannose-modified NDs reduce E. coli biofilm formation, a property previously not observed for multivalent glyco-nanoparticles and rarely demonstrated for other multivalent or monovalent mannose glycans. This work sets the stage for the further evaluation of these novel NDs as an anti-adhesive therapeutic strategy against E. coli-derived infections.

A postoperative anti-adhesion barrier based on photoinduced imine-crosslinking hydrogel with tissue-adhesive ability.

PubMed

Yang, Yunlong; Liu, Xiaolin; Li, Yan; Wang, Yang; Bao, Chunyan; Chen, Yunfeng; Lin, Qiuning; Zhu, Linyong

2017-10-15

Postoperative adhesion is a serious complication that can further lead to morbidity and/or mortality. Polymer anti-adhesion barrier material provides an effective precaution to reduce the probability of postoperative adhesion. Clinical application requires these materials to be easily handled, biocompatible, biodegradable, and most importantly tissue adherent to provide target sites with reliable isolation. However, currently there is nearly no polymer barrier material that can fully satisfy these requirements. In this study, based on the photoinduced imine-crosslinking (PIC) reaction, we had developed a photo-crosslinking hydrogel (CNG hydrogel) that composed of o-nitrobenzyl alcohol (NB) modified carboxymethyl cellulose (CMC-NB) and glycol chitosan (GC) as an anti-adhesion barrier material. Under light irradiation, CMC-NB generated aldehyde groups which subsequently reacted with amino groups distributed on GC or tissue surface to form a hydrogel barrier that covalently attached to tissue surface. Rheological analysis demonstrated that CNG hydrogel (30mg/mL polymer content) could be formed in 30s upon light irradiation. Tissue adhesive tests showed that the tissue adhesive strength of CNG hydrogel (30mg/mL) was about 8.32kPa-24.65kPa which increased with increasing CMC-NB content in CNG hydrogel. Toxicity evaluation by L929 cells demonstrated that CNG hydrogel was cytocompatible. Furthermore, sidewall defect-cecum abrasion model of rat was employed to evaluate the postoperative anti-adhesion efficacy of CNG hydrogel. And a significantly reduction of tissue adhesion (20% samples with low score adhesion) was found in CNG hydrogel treated group, compared with control group (100% samples with high score adhesion). In addition, CNG hydrogel could be degraded in nearly 14days and showed no side effect on wound healing. These findings indicated that CNG hydrogel can effectively expanded the clinical treatments of postoperative tissue adhesion. In this study, a tissue adhesive photo-crosslinking hydrogel (CNG) was developed based on photo-induced imine crosslinking reaction (PIC) for postoperative anti-adhesion. CNG hydrogel showed the features of easy and convenient operation, fast and controllable gelation, suitable gel strength, good biocompatibility, and most importantly strong tissue adhesiveness. Therefore, it shows very high performance to prevent postoperative tissue adhesion. Overall, our study provides a more suitable hydrogel barrier material that can overcome the shortcomings of current barriers for clinical postoperative anti-adhesion. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Fabrication of Novel Hydrogel with Berberine-Enriched Carboxymethylcellulose and Hyaluronic Acid as an Anti-Inflammatory Barrier Membrane

PubMed Central

Huang, Yu-Chih; Huang, Kuen-Yu; Yang, Bing-Yuan

2016-01-01

An antiadhesion barrier membrane is an important biomaterial for protecting tissue from postsurgical complications. However, there is room to improve these membranes. Recently, carboxymethylcellulose (CMC) incorporated with hyaluronic acid (HA) as an antiadhesion barrier membrane and drug delivery system has been reported to provide excellent tissue regeneration and biocompatibility. The aim of this study was to fabricate a novel hydrogel membrane composed of berberine-enriched CMC prepared from bark of the P. amurense tree and HA (PE-CMC/HA). In vitro anti-inflammatory properties were evaluated to determine possible clinical applications. The PE-CMC/HA membranes were fabricated by mixing PE-CMC and HA as a base with the addition of polyvinyl alcohol to form a film. Tensile strength and ultramorphology of the membrane were evaluated using a universal testing machine and scanning electron microscope, respectively. Berberine content of the membrane was confirmed using a UV-Vis spectrophotometer at a wavelength of 260 nm. Anti-inflammatory property of the membrane was measured using a Griess reaction assay. Our results showed that fabricated PE-CMC/HA releases berberine at a concentration of 660 μg/ml while optimal plasticity was obtained at a 30 : 70 PE-CMC/HA ratio. The berberine-enriched PE-CMC/HA had an inhibited 60% of inflammation stimulated by LPS. These results suggest that the PE-CMC/HA membrane fabricated in this study is a useful anti-inflammatory berberine release system. PMID:28119926

A simple and rapid method for optical visualization and quantification of bacteria on textiles

PubMed Central

Stiefel, Philipp; Schneider, Jana; Amberg, Caroline; Maniura-Weber, Katharina; Ren, Qun

2016-01-01

To prevent bacterial contamination on textiles and the associated undesired effects different biocidal coatings have been investigated and applied. However, due to health and environmental concerns anti-adhesive coatings preventing the binding of bacteria would be favored. To develop such anti-adhesive coatings simple assays for reliable and fast screening are beneficial. Here an easy-to-handle, robust and rapid assay to assess bacteria on textiles utilizing a tetrazolium salt was reported. The assay allowed direct eye visualization of the color change of the textiles containing bacteria, facilitating fast screening. Quantification of the adhered bacteria could be done by generating standard curves which correlate the staining intensity to cell numbers. An additional advantage of the described assay is that with the same detection method anti-adhesive and biocidal effects can be investigated. The method was applied to different coatings, using Pseudomonas aeruginosa and Staphylococcus aureus as model organisms. The detection limit was found to be between 2.5 * 106 and 9.4 * 108 for P. aeruginosa and between 1 * 106 and 3.3 * 108 for S. aureus. The anti-adhesive coating PLUMA was demonstrated to reduce bacterial adhesion without killing them, whereas the biocidal coating TH22-27 caused a clear reduction in the number of viable cells. PMID:28004762

Heterofunctional nanosheet controlling cell adhesion properties by collagen coating.

PubMed

Niwa, Daisuke; Fujie, Toshinori; Lang, Thorsten; Goda, Nobuhito; Takeoka, Shinji

2012-08-01

Recently, biomaterials have been widely used in a variety of medical applications. We previously reported that a poly-l-lactic acid (PLLA) nanosheet shows anti-adhesive properties and constitutes a useful biomaterial for preventing unwanted wound adhesion in surgical operations. In this article, we examine whether the PLLA nanosheet can be specifically modified with biomacromolecules on one surface only. Such an approach would endow each side of the nanosheet with discrete functions, that is anti-adhesive and pro-healing properties. We fabricated two distinct PLLA nanosheets: (i) collagen cast on the surface of a PLLA nanosheet (Col-Cast-PLLA) and (ii) collagen spin-coated on the nanosheet (Col-Spin-PLLA). In the Col-Spin-PLLA nanosheet, the collagen layer had a thickness of 5-10 nm on the PLLA surface and displayed increased hydrophilicity compared to both PLLA and Col-Cast-PLLA nanosheets. In addition, atomic force microscopy showed disorganized collagen fibril formation on the PLLA layer when covered using the spin-coating method, while apparent bundle formations of collagen were formed in the Col-Cast-PLLA nanosheet. The Col-Spin-PLLA nanosheet provided a microenvironment for cells to adhere and spread. By contrast, the Col-Cast-PLLA nanosheet displayed reduced cell adhesion compared to the Col-Spin-PLLA nanosheet. Consistent with these findings, immunocytochemical analysis clearly showed fine networks of actin filaments in cells cultured on the Col-Spin-PLLA, but not the Col-Cast-PLLA nanosheet. Therefore, the Col-Spin-PLLA nanosheet was shown to be more suitable for acting as a scaffold. In conclusion, we have succeeded in developing a heterofunctional nanosheet comprising a collagen modified side, which has the ability to rapidly adhere cells, and an unmodified side, which acts as an adhesion barrier, by using a spin-coating technique.

Evaluation of the anti-adhesive effect of milk fat globule membrane glycoproteins on Helicobacter pylori in the human NCI-N87 cell line and C57BL/6 mouse model.

PubMed

Horemans, Tessa; Kerstens, Monique; Clais, Sofie; Struijs, Karin; van den Abbeele, Pieter; Van Assche, Tim; Maes, Louis; Cos, Paul

2012-08-01

 The interest in non-antibiotic therapies for Helicobacter pylori infections in man has considerably grown because increasing numbers of antibiotic-resistant strains are being reported. Intervention at the stage of bacterial attachment to the gastric mucosa could be an approach to improve the control/eradication rate of this infection.  Fractions of purified milk fat globule membrane glycoproteins were tested in vitro for their cytotoxic and direct antibacterial effect. The anti-adhesive effect on H. pylori was determined first in a cell model using the mucus-producing gastric epithelial cell line NCI-N87 and next in the C57BL/6 mouse model after dosing at 400 mg/kg protein once or twice daily from day -2 to day 4 post-infection. Bacterial loads were determined by using quantitative real-time PCR and the standard plate count method.  The milk fat globule membrane fractions did not show in vitro cytotoxicity, and a marginal antibacterial effect was demonstrated for defatted milk fat globule membrane at 256 μg/mL. In the anti-adhesion assay, the results varied from 56.0 ± 5.3% inhibition for 0.3% crude milk fat globule membrane to 79.3 ± 3.5% for defatted milk fat globule membrane. Quite surprisingly, in vivo administration of the same milk fat globule membrane fractions did not confirm the anti-adhesive effects and even caused an increase in bacterial load in the stomach.  The promising anti-adhesion in vitro results could not be confirmed in the mouse model, even after the highest attainable exposure. It is concluded that raw or defatted milk fat globule membrane fractions do not have any prophylactic or therapeutic potential against Helicobacter infection. © 2012 Blackwell Publishing Ltd.

Bioprosthetic Mesh in Abdominal Wall Reconstruction

PubMed Central

Baumann, Donald P.; Butler, Charles E.

2012-01-01

Mesh materials have undergone a considerable evolution over the last several decades. There has been enhancement of biomechanical properties, improvement in manufacturing processes, and development of antiadhesive laminate synthetic meshes. The evolution of bioprosthetic mesh materials has markedly changed our indications and methods for complex abdominal wall reconstruction. The authors review the optimal properties of bioprosthetic mesh materials, their evolution over time, and their indications for use. The techniques to optimize outcomes are described using bioprosthetic mesh for complex abdominal wall reconstruction. Bioprosthetic mesh materials clearly have certain advantages over other implantable mesh materials in select indications. Appropriate patient selection and surgical technique are critical to the successful use of bioprosthetic materials for abdominal wall repair. PMID:23372454

Immobilized liquid layers: A new approach to anti-adhesion surfaces for medical applications

PubMed Central

Sotiri, Irini; Overton, Jonathan C; Waterhouse, Anna

2016-01-01

Surface fouling and undesired adhesion are nearly ubiquitous problems in the medical field, complicating everything from surgeries to routine daily care of patients. Recently, the concept of immobilized liquid (IL) interfaces has been gaining attention as a highly versatile new approach to antifouling, with a wide variety of promising applications in medicine. Here, we review the general concepts behind IL layers and discuss the fabrication strategies on medically relevant materials developed so far. We also summarize the most important findings to date on applications of potential interest to the medical community, including the use of these surfaces as anti-thrombogenic and anti-bacterial materials, anti-adhesive textiles, high-performance coatings for optics, and as unique platforms for diagnostics. Although the full potential and pitfalls of IL layers in medicine are just beginning to be explored, we believe that this approach to anti-adhesive surfaces will prove broadly useful for medical applications in the future. PMID:27022136

Anti-Adhesive Activity of Cranberry Phenolic Compounds and Their Microbial-Derived Metabolites against Uropathogenic Escherichia coli in Bladder Epithelial Cell Cultures.

PubMed

de Llano, Dolores González; Esteban-Fernández, Adelaida; Sánchez-Patán, Fernando; Martínlvarez, Pedro J; Moreno-Arribas, Maria Victoria; Bartolomé, Begoña

2015-05-27

Cranberry consumption has shown prophylactic effects against urinary tract infections (UTI), although the mechanisms involved are not completely understood. In this paper, cranberry phenolic compounds and their potential microbial-derived metabolites (such as simple phenols and benzoic, phenylacetic and phenylpropionic acids) were tested for their capacity to inhibit the adherence of uropathogenic Escherichia coli (UPEC) ATCC®53503™ to T24 epithelial bladder cells. Catechol, benzoic acid, vanillic acid, phenylacetic acid and 3,4-dihydroxyphenylacetic acid showed anti-adhesive activity against UPEC in a concentration-dependent manner from 100-500 µM, whereas procyanidin A2, widely reported as an inhibitor of UPEC adherence on uroepithelium, was only statistically significant (p < 0.05) at 500 µM (51.3% inhibition). The results proved for the first time the anti-adhesive activity of some cranberry-derived phenolic metabolites against UPEC in vitro, suggesting that their presence in the urine could reduce bacterial colonization and progression of UTI.

Tunneled catheters with taurolidine-citrate-heparin lock solution significantly improve the inflammatory profile of hemodialysis patients.

PubMed

Fontseré, Néstor; Cardozo, Celia; Donate, Javier; Soriano, Alex; Muros, Mercedes; Pons, Mercedes; Mensa, Josep; Campistol, Josep M; Navarro-González, Juan F; Maduell, Francisco

2014-07-01

Mortality and morbidity are significantly higher among patients with dialysis catheters, which has been associated with chronic activation of the immune system. We hypothesized that bacteria colonizing the catheter lumen trigger an inflammatory response. We aimed to evaluate the inflammatory profile of hemodialysis patients before and after locking catheters with an antimicrobial lock solution. High-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), IL-10, and tumor necrosis factor alpha (TNF-α) were measured in serum, and levels of mRNA gene expression of IL-6, IL-10, and TNF-α were analyzed in peripheral blood mononuclear cells (PBMC). Samples were obtained at baseline and again after 3 months' use of taurolidine-citrate-heparin lock solution (TCHLS) in 31 hemodialysis patients. The rate of catheter-related bloodstream infections (CRBSI) was 1.08 per 1,000 catheter-days in the heparin period and 0.04 in the TCHLS period (P = 0.023). Compared with the baseline data, serum levels of hs-CRP and IL-6 showed median percent reductions of 18.1% and 25.2%, respectively (P < 0.01), without significant changes in TNF-α or IL-10 levels. Regarding cytokine gene expression in PBMC, the median mRNA expression levels of TNF-α and IL-6 decreased by 20% (P < 0.05) and 19.7% (P = 0.01), respectively, without changes in IL-10 expression levels. The use of TCHLS to maintain the catheter lumen sterility significantly reduces the incidence of CRBSI and improves the inflammatory profile in hemodialysis patients with tunneled catheters. Further studies are needed to evaluate the potential beneficial effects on clinical outcomes. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Tunneled Catheters with Taurolidine-Citrate-Heparin Lock Solution Significantly Improve the Inflammatory Profile of Hemodialysis Patients

PubMed Central

Cardozo, Celia; Donate, Javier; Soriano, Alex; Muros, Mercedes; Pons, Mercedes; Mensa, Josep; Campistol, Josep M.; Navarro-González, Juan F.; Maduell, Francisco

2014-01-01

Mortality and morbidity are significantly higher among patients with dialysis catheters, which has been associated with chronic activation of the immune system. We hypothesized that bacteria colonizing the catheter lumen trigger an inflammatory response. We aimed to evaluate the inflammatory profile of hemodialysis patients before and after locking catheters with an antimicrobial lock solution. High-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), IL-10, and tumor necrosis factor alpha (TNF-α) were measured in serum, and levels of mRNA gene expression of IL-6, IL-10, and TNF-α were analyzed in peripheral blood mononuclear cells (PBMC). Samples were obtained at baseline and again after 3 months' use of taurolidine-citrate-heparin lock solution (TCHLS) in 31 hemodialysis patients. The rate of catheter-related bloodstream infections (CRBSI) was 1.08 per 1,000 catheter-days in the heparin period and 0.04 in the TCHLS period (P = 0.023). Compared with the baseline data, serum levels of hs-CRP and IL-6 showed median percent reductions of 18.1% and 25.2%, respectively (P < 0.01), without significant changes in TNF-α or IL-10 levels. Regarding cytokine gene expression in PBMC, the median mRNA expression levels of TNF-α and IL-6 decreased by 20% (P < 0.05) and 19.7% (P = 0.01), respectively, without changes in IL-10 expression levels. The use of TCHLS to maintain the catheter lumen sterility significantly reduces the incidence of CRBSI and improves the inflammatory profile in hemodialysis patients with tunneled catheters. Further studies are needed to evaluate the potential beneficial effects on clinical outcomes. PMID:24820084

Staphylococcus haemolyticus as a potential producer of biosurfactants with antimicrobial, anti-adhesive and synergistic properties.

PubMed

Rossi, C C; Santos-Gandelman, J F; Barros, E M; Alvarez, V M; Laport, M S; Giambiagi-deMarval, M

2016-09-01

Staphylococcus haemolyticus is an opportunistic human pathogen that usually gains entry into the host tissue in association with medical device contamination. Biofilm formation is a key factor for the establishment of this bacterium and its arrangement and dynamics can be influenced by the synthesis of biosurfactants. Biosurfactants are structurally diverse amphiphilic molecules with versatile biotechnological applications, but information on their production by staphylococci is still scarce. In this work, two Staph. haemolyticus strains, showing high potential for biosurfactant production - as observed by four complementary methods - were investigated. Biosurfactant extracts were produced and studied for their capacity to inhibit the growth and biofilm formation by other bacterial human pathogens. The biosurfactant produced by the one of the strains inhibited the growth of most bacteria tested and subinhibitory concentrations of the biosurfactant were able to decrease biofilm formation and showed synergistic effects with tetracycline. Because these results were also positive when the biosurfactants were tested against the producing strains, it is likely that biosurfactant production by Staph. haemolyticus may be an unexplored virulence factor, important for competition and biofilm formation by the bacterium, in addition to the biotechnological potential. This work is the first to show the production of biosurfactants by Staphylococcus haemolyticus strains. Extracts showed antimicrobial, anti-adhesive and synergistic properties against a variety of relevant human pathogens, including the producing strains. In addition to the biotechnological potential, biosurfactants produced by Staph. haemolyticus are potentially undescribed virulence determinants in their producing strains. © 2016 The Society for Applied Microbiology.

Evaluation of adhesive and anti-adhesive properties of Pseudomonas aeruginosa biofilms and their inhibition by herbal plants

PubMed Central

Zameer, Farhan; MS, Rukmangada; Chauhan, Jyoti Bala; Khanum, Shaukath Ara; Kumar, Pramod; Devi, Aishwarya Tripurasundari; MN, Nagendra Prasad; BL, Dhananjaya

2016-01-01

Background and Objectives: Adhesion and colonization are prerequisites for the establishment of bacterial pathogenesis. The biofilm development of Pseudomonas aeruginosa was assessed on adhesive surfaces like dialysis membrane, stainless steel, glass and polystyrene. Materials and Methods: Microtiter plate biofilm assay was performed to assess the effect of nutrient medium and growth parameters of P. aeruginosa. Further, its growth on adhesive surfaces namely hydrophilic (dialysis membrane) and hydrophobic (polystyrene plate, square glass and stainless steel coupon) was assessed. The exopolysaccharide (EPS) was quantified using ruthenium red microplate assay and microscopic analysis was used to observe P. aeruginosa biofilm architecture. The anti-biofilm activity of herbal extracts on mature P. aeruginosa was performed. Results: The formation of large scale biofilms on dialysis membrane for 72 h was proved to be the best surface. In microscopic studies, very few exopolysaccaride fibrils, indicating a rather loose matrix was observed at 48 h. Further, thick exopolysaccaride, indicated higher adhesive properties at 72 h which is evident from ruthenium red staining. Among the plant extract used, Justicia wynaadensis leaf and Aristolochia indica (Eswari) root extract showed significant reduction of anti-biofilm activity of 0.178 OD and 0.192 OD in inhibiting mature biofilms at 0.225 OD respectively, suggesting the possible use of these extracts as efficient anti-adhesive and biofilm-disrupting agents with potential applications in controlling biofilms on surfaces. Conclusion: Our study facilitates better understanding in the development of P. aeruginosa biofilms on different food processing and clinical surfaces ultimately taking care of food safety and hygiene. PMID:27307976

Anti-bacterial properties of ultrafiltration membrane modified by graphene oxide with nano-silver particles.

PubMed

Li, Jingchun; Liu, Xuyang; Lu, Jiaqi; Wang, Yudan; Li, Guanglu; Zhao, Fangbo

2016-12-15

To improve the anti-biofouling properties of PVDF membranes, GO-Ag composites were synthesized and used as membrane antibacterial agent by a simple and environmentally friendly method. As identified by XRD, TEM and FTIR analysis, AgNPs were uniformly assembled on the synthesized GO-Ag sheets. The membranes were prepared by phase inversion method with different additional amounts (0.00-0.15wt%) of GO-Ag composites. The GO-Ag composites modified membranes show improved hydrophilicity, mechanical property and permeability than unmodified PVDF membrane. Specially, the antibacterial properties and inhibition of biofilm formation were greatly enhanced based on conventional inhibition zone test and anti-adhesion of bacterial experiment. The modified membranes also reveal a remarkable long-term continuous antimicrobial activity with slower release rate of Ag + compared to AgNPs/PVDF membrane. Copyright © 2016 Elsevier Inc. All rights reserved.

Antiadhesive activity of poly-hydroxy butyrate biopolymer from a marine Brevibacterium casei MSI04 against shrimp pathogenic vibrios.

PubMed

Kiran, George Seghal; Lipton, Anuj Nishanth; Priyadharshini, Sethu; Anitha, Kumar; Suárez, Lucia Elizabeth Cruz; Arasu, Mariadhas Valan; Choi, Ki Choon; Selvin, Joseph; Al-Dhabi, Naif Abdullah

2014-08-13

Vibrio pathogens are causative agents of mid-culture outbreaks, and early mortality syndrome and secondary aetiology of most dreadful viral outbreaks in shrimp aquaculture. Among the pathogenic vibrios group, Vibrio alginolyticus and V. harveyi are considered as the most significant ones in the grow-out ponds of giant black tiger shrimp Penaeus monodon in India. Use of antibiotics was banned in many countries due to the emergence of antibiotic-resistant strains and accumulation of residual antibiotics in harvested shrimp. There is an urgent need to consider the use of alternative antibiotics for the control of vibriosis in shrimp aquaculture. Biofilm formation is a pathogenic and/or establishment mechanism of Vibrio spp. This study aims to develop novel safe antibiofilm and/or antiadhesive process using PHB to contain vibrios outbreaks in shrimp aquaculture. In this study a poly-hydroxy butyrate (PHB) polymer producing bacterium Brevibacterium casei MSI04 was isolated from a marine sponge Dendrilla nigra and production of PHB was optimized under submerged-fermentation (SmF) conditions. The effect of carbon, nitrogen and mineral sources on PHB production and enhanced production of PHB by response surface methods were demonstrated. The maximum PHB accumulation obtained was 6.74 g/L in the optimized media containing 25 g/L starch as carbon source, 96 h of incubation, 35°C and 3% NaCl. The highest antiadhesive activity upto 96% was recorded against V. vulnificus, and V. fischeri, followed by 92% against V. parahaemolyticus and V. alginolyticus and 88% inhibition was recorded against V. harveyi. In this study, a thermostable biopolymer was chemically characterized as PHB based on 1HNMR spectra, FT-IR and GC-MS spectra. The NMR spectra revealed that the polymer was an isocratic homopolymer and it also confirmed that the compound was PHB. The antiadhesive activity of PHB was determined in microtitre plate assay and an effective concentration (EC) of PHB (200 μl containing 0.6 mg PHB) was confirmed by confocal laser scanning microscopic analysis of vibrio biofilm on pre-treated glass and polystyrene surfaces. This is a first report on anti-adhesive activity of PHB against prominent vibrio pathogens in shrimp aquaculture.

Development of anti-adhesive spongy sheet composed of hyaluronic acid and collagen containing epidermal growth factor.

PubMed

Kuroyanagi, Misato; Yamamoto, Akiko; Shimizu, Nahoko; Toi, Ayako; Inomata, Tomonori; Takeda, Akira; Kuroyanagi, Yoshimitsu

2014-01-01

Anti-adhesive products need to be designed while considering the concept of wound healing. Two main events must proceed simultaneously: facilitating wound healing in surgically excised tissue, as well as preventing injured tissue from adhering to the surrounding tissue. The present study aimed to develop an anti-adhesive spongy sheet composed of hyaluronic acid and collagen (Col) containing epidermal growth factor, and to investigate the potential of this spongy sheet using an in vitro wound surface model (placing a spongy sheet on a fibroblast-incorporating Col gel sheet) and an in vitro inter-tissue model (placing a spongy sheet between two fibroblast-incorporating Col gel sheets). These in vitro experiments demonstrated that this spongy sheet effectively stimulates fibroblasts to release an increased amount of vascular endothelial growth factor and hepatocyte growth factor, which are essential for wound healing to proceed succesfully. In addition, anti-adhesive performance of this spongy sheet was evaluated in animal experiments using Sprague Dawley rats. Under anesthesia, a 1 cm × 2 cm segment of peritoneum was superficially excised from walls, and the cecum was then abraded by scraping with a scalpel blade over a 1 cm × 2 cm area. A piece of spongy sheet was placed on the peritoneal defect. Both defects were placed in contact, and the incision was closed by suturing. Peritoneal condition was evaluated after one week. This spongy sheet was capable of facilitating the wound healing of surgically excised tissue and preventing surgically excised tissue from adhering to surrounding tissues.

Gravidity-Dependent Production of Antibodies That Inhibit Binding of Plasmodium falciparum-Infected Erythrocytes to Placental Chondroitin Sulfate Proteoglycan during Pregnancy

PubMed Central

O'Neil-Dunne, Iona; Achur, Rajeshwara N.; Agbor-Enoh, Sean T.; Valiyaveettil, Manojkumar; Naik, Ramachandra S.; Ockenhouse, Christian F.; Zhou, Ainong; Megnekou, Rosette; Leke, Rose; Taylor, Diane W.; Gowda, D. Channe

2001-01-01

During pregnancy, Plasmodium falciparum-infected erythrocytes sequester in the placenta by adhering to chondroitin 4-sulfate, creating a risk factor for both the mother and the fetus. The primigravidae are at higher risk for placental malaria than the multigravidae. This difference in susceptibility has been attributed to the lack of antibodies that block the adhesion of infected erythrocytes to placental chondroitin 4-sulfate in primigravid women. However, recent results show that many primigravidae at term have antibody levels similar to those of multigravidae, and thus the significance of antiadhesion antibodies in providing protection against malaria during pregnancy remains unclear. In this study, we analyzed plasma samples from women of various gravidities at different gestational stages for antiadhesion antibodies. The majority of women, regardless of gravidity, had similar levels of antibodies at term. Most primigravidae had low levels of or no antiadhesion antibodies prior to ∼20 weeks of pregnancy and then produced antibodies. Multigravidae also lacked antibodies until ∼12 weeks of pregnancy, but thereafter they efficiently produced antibodies. In pregnant women who had placental infection at term, higher levels of antiadhesion antibodies correlated with lower levels of placental parasitemia. The difference in kinetics of antibody production between primigravidae and multigravidae correlated with the prevalence of malaria in these groups, suggesting that antibodies are produced during pregnancy in response to placental infection. The early onset of efficient antibody response in multigravidae and the delayed production to antibodies in primigravidae appear to account for the gravidity-dependent differential susceptibilities of pregnant women to placental malaria. PMID:11705924

Role of anti-adhesive barriers following rotator cuff repair surgery: an experimental study.

PubMed

Kalem, Mahmut; Şahin, Ercan; Songür, Murat; Zehir, Sinan; Armangil, Mehmet; Demirtaş, Mehmet A

2016-01-01

This experimental study investigates the effectiveness of expanded polytetrafluoroethylene (Dualmesh®, Gore Medical, Flagstaff, AZ, USA), sodium hyaluronate-carboxymethyl cellulose (Seprafilm®, Genzyme, Cambridge, MA, USA), and polysiloxane (silicone) as anti-adhesive barriers for inhibition of fibrosis in the subacromial area following rotator cuff repair. Rabbit rotator cuff tenotomy and repair was conducted on 24 rabbits in 4 groups: control (Group A), Dualmesh® (Group B), Seprafilm® (Group C), and silicone (Group D). Anti-adhesive barrier materials were sutured over the repaired rotator cuff. Macroscopic and histological evaluations were made at the end of the sixth postoperative week. Macroscopic evaluation revealed that minimal adhesion occurred in the control and silicone groups, while the Seprafilm® and Dualmesh® groups showed evidence of fibrosis. Microscopic evaluation revealed diffuse fibrosis and collagen accumulation in the Dualmesh® and Seprafilm® groups, whereas minimal collagen deposition and inflammatory cell reaction was found among the silicone and control groups. Significant differences were found between the silicone and Dualmesh® (p=0.001) and silicone and Seprafilm® groups (p=0.002), as well as between the control and Dualmesh® (p=0.002) and control and Seprafilm® groups (p=0.002). Expanded polytetrafluoroethylene (ePTFE/Dualmesh®) and sodium hyaluronate carboxymethyl cellulose (SH-CMC/Seprafilm®) did not prevent or attenuate postoperative subacromial fibrosis following cuff tear repair. Nor did silicone prevent or attenuate fibrosis. More detailed research is needed for development of an effective anti-adhesive barrier for use after rotator cuff tear surgery.

Gravidity-dependent production of antibodies that inhibit binding of Plasmodium falciparum-infected erythrocytes to placental chondroitin sulfate proteoglycan during pregnancy.

PubMed

O'Neil-Dunne, I; Achur, R N; Agbor-Enoh, S T; Valiyaveettil, M; Naik, R S; Ockenhouse, C F; Zhou, A; Megnekou, R; Leke, R; Taylor, D W; Gowda, D C

2001-12-01

During pregnancy, Plasmodium falciparum-infected erythrocytes sequester in the placenta by adhering to chondroitin 4-sulfate, creating a risk factor for both the mother and the fetus. The primigravidae are at higher risk for placental malaria than the multigravidae. This difference in susceptibility has been attributed to the lack of antibodies that block the adhesion of infected erythrocytes to placental chondroitin 4-sulfate in primigravid women. However, recent results show that many primigravidae at term have antibody levels similar to those of multigravidae, and thus the significance of antiadhesion antibodies in providing protection against malaria during pregnancy remains unclear. In this study, we analyzed plasma samples from women of various gravidities at different gestational stages for antiadhesion antibodies. The majority of women, regardless of gravidity, had similar levels of antibodies at term. Most primigravidae had low levels of or no antiadhesion antibodies prior to ~20 weeks of pregnancy and then produced antibodies. Multigravidae also lacked antibodies until ~12 weeks of pregnancy, but thereafter they efficiently produced antibodies. In pregnant women who had placental infection at term, higher levels of antiadhesion antibodies correlated with lower levels of placental parasitemia. The difference in kinetics of antibody production between primigravidae and multigravidae correlated with the prevalence of malaria in these groups, suggesting that antibodies are produced during pregnancy in response to placental infection. The early onset of efficient antibody response in multigravidae and the delayed production to antibodies in primigravidae appear to account for the gravidity-dependent differential susceptibilities of pregnant women to placental malaria.

Antiadhesion and anti-inflammation effects of noni (Morinda citrifolia) fruit extracts on AGS cells during Helicobacter pylori infection.

PubMed

Huang, Hsin-Lun; Ko, Chien-Hui; Yan, Yeong-Yu; Wang, Chin-Kun

2014-03-19

Helicobacter pylori is a human gastric pathogen that adheres to host cells and injects cytotoxin-associated gene A (CagA) to induce interleukin-8 (IL-8), inducible nitric oxide (iNOS), and cyclooxygenase 2 (COX-2). Noni (Morinda citrifolia) is found to possess antibacteria, anti-inflammation, and antioxidation activities, but its effect on H. pylori infection is still unknown. Ethanol and ethyl acetate extracts of noni fruit were used in this study. The inhibitory effect on CagA and H. pylori-induced IL-8, iNOS, and COX-2 were determined. The coculture medium was collected for measuring neutrophil chemotaxis. Both extracts of noni fruit showed weak inhibition on H. pylori. Both ethanol and ethyl acetate extracts provided antiadhesion of H. pylori to AGS cells and down-regulation on the CagA, IL-8, COX-2, and iNOS expressions. Results also indicated both extracts relieved neutrophil chemotaxis. Noni fruit extracts down-regulated inflammatory responses during H. pylori infection, and the phenolic compounds play key role in antiadhesion.

Application of hyaluronic acid/sodium alginate-based microparticles to prevent tissue adhesion in a rabbit model.

PubMed

Back, Ja Hoon; Cho, Wan Jin; Kim, Jun Ho; Park, Il Kyu; Kwon, Sung Won

2016-04-01

Postsurgical adhesion formation is a concern in every field of surgery. We evaluated the efficacy of hyaluronic acid/sodium alginate-based microparticle anti-adhesive agents (MP) for the prevention of postsurgical adhesion formation in a standardized rabbit model. To evaluate the anti-adhesion effect, a uterus-abdominal wall abrasion model was created in rabbits. On the surface of the injured uterus, an anti-adhesive agent, Interceed(®) or MP, was applied (positive control and study groups, respectively; n = 10 each). In another group of 10 animals, neither agent was applied (negative control group). The adhesion levels were graded 3 weeks after surgery. Acute and chronic toxicity was also evaluated. The grade of adhesion was significantly lower in the MP group than in the negative control and positive control groups. No evidence of acute or chronic toxicity induced by this material was found in blood and tissue analysis. MP shows potential as an effective novel type of resorbable biomaterial to reduce postoperative adhesion. The easy placement and handling of this material make the MP powder attractive as a tissue adhesion barrier.

Antiadhesive effect of polyurethane foam packing in the guinea pig middle ear.

PubMed

Choi, Cheol Hee; Jang, Chul Ho

2015-02-01

No significant subepithelial healing differences were found between Gelfoam and polyurethane foam (PUF). However, levels of hyperplasia of the mucosal lining and inflammation were lower with PUF packing. PUF packing is not feasible as a middle ear packing material for abraded mucosa. Further studies are required before clinical application. To date, there have been few reports on the antiadhesive effect of PUF as a middle ear packing. The purpose of this study was to investigate the antiadhesive effect of PUF soaked with saline in an animal model of mucosal trauma. Bioresorbable PUF soaked with saline was placed over abraded mucosa in the experimental group (n = 7), and compressed Gelfoam soaked with saline was placed in the control group (n = 7). After measurement of auditory brainstem responses (ABRs), the animals were sacrificed 3 weeks after packing placement for histological observation. The ABR results at postoperative week 3 showed no statistically significant difference between the preoperative and post-packing values. An adhesion pattern with subepithelial thickening was observed in the control group. Adhesion was not observed in the experimental group; however, subepithelial fibrous thickening was noted.

Methodologies for screening of bacteria-carbohydrate interactions: anti-adhesive milk oligosaccharides as a case study.

PubMed

Lane, Jonathan A; Mariño, Karina; Rudd, Pauline M; Carrington, Stephen D; Slattery, Helen; Hickey, Rita M

2012-07-01

Many studies have demonstrated the capacity of glycan-based compounds to disrupt microbial binding to mucosal epithelia. Therefore, oligosaccharides have potential application in the prevention of certain bacterial diseases. However, current screening methods for the identification of anti-adhesive oligosaccharides have limitations: they are time-consuming and require large amounts of oligosaccharides. There is a need to develop analytical techniques which can quickly screen for, and structurally define, anti-adhesive oligosaccharides prior to using human cell line models of infection. Considering this, we have developed a rapid method for screening complex oligosaccharide mixtures for potential anti-adhesive activity against bacteria. Our approach involves the use of whole bacterial cells to "deplete" free oligosaccharides from solution. As a case study, the free oligosaccharides from the colostrum of Holstein Friesian cows were screened for interactions with whole Escherichia coli cells. Reductions in oligosaccharide concentrations were determined by High pH Anion Exchange Chromatography and Hydrophilic Interaction Liquid Chromatography (HILIC-HPLC). Oligosaccharide structures were confirmed by a combination of HILIC-HPLC, exoglycosidase digestion and off-line negative ion mode MS/MS. The depletion assay confirmed selective bacterial interaction with certain bovine oligosaccharides which in previous studies, by other methodologies, had been shown to interact with E. coli. In particular, the bacterial cells depleted the following oligosaccharides in a population dependent manner: 3'-sialyllactose, disialyllactose, and 6'-sialyllactosamine. The assay methodology was further validated by studies in which we demonstrated the inhibitory activity of 3'-sialyllactose, and a mixture of bovine colostrum oligosaccharides, on E. coli adhesion to differentiated HT-29 cells. Copyright © 2012 Elsevier B.V. All rights reserved.

Predictive modelling of a novel anti-adhesion therapy to combat bacterial colonisation of burn wounds

PubMed Central

Huebinger, Ryan M.; Keen, Emma

2018-01-01

As the development of new classes of antibiotics slows, bacterial resistance to existing antibiotics is becoming an increasing problem. A potential solution is to develop treatment strategies with an alternative mode of action. We consider one such strategy: anti-adhesion therapy. Whereas antibiotics act directly upon bacteria, either killing them or inhibiting their growth, anti-adhesion therapy impedes the binding of bacteria to host cells. This prevents bacteria from deploying their arsenal of virulence mechanisms, while simultaneously rendering them more susceptible to natural and artificial clearance. In this paper, we consider a particular form of anti-adhesion therapy, involving biomimetic multivalent adhesion molecule 7 coupled polystyrene microbeads, which competitively inhibit the binding of bacteria to host cells. We develop a mathematical model, formulated as a system of ordinary differential equations, to describe inhibitor treatment of a Pseudomonas aeruginosa burn wound infection in the rat. Benchmarking our model against in vivo data from an ongoing experimental programme, we use the model to explain bacteria population dynamics and to predict the efficacy of a range of treatment strategies, with the aim of improving treatment outcome. The model consists of two physical compartments: the host cells and the exudate. It is found that, when effective in reducing the bacterial burden, inhibitor treatment operates both by preventing bacteria from binding to the host cells and by reducing the flux of daughter cells from the host cells into the exudate. Our model predicts that inhibitor treatment cannot eliminate the bacterial burden when used in isolation; however, when combined with regular or continuous debridement of the exudate, elimination is theoretically possible. Lastly, we present ways to improve therapeutic efficacy, as predicted by our mathematical model. PMID:29723210

Inhibitory effect of 1,2,4-triazole-ciprofloxacin hybrids on Haemophilus parainfluenzae and Haemophilus influenzae biofilm formation in vitro under stationary conditions.

PubMed

Kosikowska, Urszula; Andrzejczuk, Sylwia; Plech, Tomasz; Malm, Anna

2016-10-01

Haemophilus parainfluenzae and Haemophilus influenzae, upper respiratory tract microbiota representatives, are able to colonize natural and artificial surfaces as biofilm. The aim of the present study was to assay the effect of ten 1,2,4-triazole-ciprofloxacin hybrids on planktonic or biofilm-forming haemophili cells in vitro under stationary conditions on the basis of MICs (minimal inhibitory concentrations) and MBICs (minimal biofilm inhibitory concentrations). In addition, anti-adhesive properties of these compounds were examined. The reference strains of H. parainfluenzae and H. influenzae were included. The broth microdilution microtiter plate (MTP) method with twofold dilution of the compounds, or ciprofloxacin (reference agent) in 96-well polystyrene microplates, was used. The optical density (OD) reading was made spectrophotometrically at a wavelength of 570 nm (OD570) both to measure bacterial growth and to detect biofilm-forming cells under the same conditions with 0.1% crystal violet. The following values of parameters were estimated for 1,2,4-triazole-ciprofloxacin hybrids - MIC = 0.03-15.63 mg/L, MBIC = 0.03-15.63 mg/L, MBIC/MIC = 0.125-8, depending on the compound, and for ciprofloxacin - MIC = 0.03-0.06 mg/L, MBIC = 0.03-0.12 mg/L, MBIC/MIC = 1-2. The observed strong anti-adhesive properties (95-100% inhibition) of the tested compounds were reversible during long-term incubation at subinhibitory concentrations. Thus, 1,2,4-triazole-ciprofloxacin hybrids may be considered as starting compounds for designing improved agents not only against planktonic but also against biofilm-forming Haemophilus spp. cells. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Flagellin based biomimetic coatings: From cell-repellent surfaces to highly adhesive coatings.

PubMed

Kovacs, Boglarka; Patko, Daniel; Szekacs, Inna; Orgovan, Norbert; Kurunczi, Sandor; Sulyok, Attila; Khanh, Nguyen Quoc; Toth, Balazs; Vonderviszt, Ferenc; Horvath, Robert

2016-09-15

Biomimetic coatings with cell-adhesion-regulating functionalities are intensively researched today. For example, cell-based biosensing for drug development, biomedical implants, and tissue engineering require that the surface adhesion of living cells is well controlled. Recently, we have shown that the bacterial flagellar protein, flagellin, adsorbs through its terminal segments to hydrophobic surfaces, forming an oriented monolayer and exposing its variable D3 domain to the solution. Here, we hypothesized that this nanostructured layer is highly cell-repellent since it mimics the surface of the flagellar filaments. Moreover, we proposed flagellin as a carrier molecule to display the cell-adhesive RGD (Arg-Gly-Asp) peptide sequence and induce cell adhesion on the coated surface. The D3 domain of flagellin was replaced with one or more RGD motifs linked by various oligopeptides modulating flexibility and accessibility of the inserted segment. The obtained flagellin variants were applied to create surface coatings inducing cell adhesion and spreading to different levels, while wild-type flagellin was shown to form a surface layer with strong anti-adhesive properties. As reference surfaces synthetic polymers were applied which have anti-adhesive (PLL-g-PEG poly(l-lysine)-graft-poly(ethylene glycol)) or adhesion inducing properties (RGD-functionalized PLL-g-PEG). Quantitative adhesion data was obtained by employing optical biochips and microscopy. Cell-adhesion-regulating coatings can be simply formed on hydrophobic surfaces by using the developed flagellin-based constructs. The developed novel RGD-displaying flagellin variants can be easily obtained by bacterial production and can serve as alternatives to create cell-adhesion-regulating biomimetic coatings. In the present work, we show for the first time that. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Antiadhesion activity of juniper (Juniperus communis L.) preparations against Campylobacter jejuni evaluated with PCR-based methods.

PubMed

Klančnik, Anja; Zorko, Špela; Toplak, Nataša; Kovač, Minka; Bucar, Franz; Jeršek, Barbara; Smole Možina, Sonja

2018-03-01

The food-borne pathogen Campylobacter jejuni can cause bacterial gastrointestinal infections. Biofilm formation amplifies the risk of human infection by improving survival and persistence of C. jejuni in food processing environments and its transmission through the food chain. We aimed to control C. jejuni using an alternative strategy of low doses of Juniperus communis fruit preparations to target bacterial adhesion properties in the first step of biofilm formation. First, we defined the anti-Campylobacter activity of a juniper fruit crude extract and its fractionated biflavonoids, flavone glycosides, and purified amentoflavone, of juniper fruit essential oil and of juniper fruit postdistillation waste material extract. For accurate quantification of adherent C. jejuni, we optimised digital Polymerase Chain Reaction (PCR) and quantitative real-time PCR for construction of standard curves and quantification. We show for the first time that juniper fruit formulations can effectively inhibit adhesion of C. jejuni to polystyrene. Furthermore, ≥94% of the antiadhesion activity of juniper fruit crude extract and juniper fruit essential oil remained under food-related conditions: modified culture medium with glucose, or a stainless steel surface, or mixed co-cultures of C. jejuni and Listeria monocytogenes. This study indicates that addition of juniper fruit formulations can control growth and adhesion of C. jejuni and thus limit food chain transmission of campylobacters. Copyright © 2017 John Wiley & Sons, Ltd.

Cranberry juice-- a well-characterized folk-remedy against bacterial urinary tract infection.

PubMed

Nowack, Rainer

2007-01-01

Cranberry (Vaccinium macrocarpon) is a North-American folk remedy for treating and preventing infection. Research has identified an anti-adhesive mechanism of cranberry-proanthocyanidins that inhibit docking of bacteria on tissues "in vitro". This efficacy mechanism can be traced in the patient's urine following oral intake of cranberry juice. The efficacy of cranberry juice and extracts as a prophylactic agent against recurrent urinary infections is well documented in women. The anti-adhesion effect of cranberry-proanthocyandins can also be applied for treatment of other common diseases of bacterial pathogenesis, e.g. Helicobacter pylori-associated gastritis and dental caries/periodontal disease.

Screening of binding activity of Streptococcus pneumoniae, Streptococcus agalactiae and Streptococcus suis to berries and juices.

PubMed

Toivanen, Marko; Huttunen, Sanna; Duricová, Jana; Soininen, Pasi; Laatikainen, Reino; Loimaranta, Vuokko; Haataja, Sauli; Finne, Jukka; Lapinjoki, Seppo; Tikkanen-Kaukanen, Carina

2010-01-01

Antiadhesion therapy is a promising approach to the fight against pathogens. Antibiotic resistance and the lack of effective vaccines have increased the search for new methods to prevent infectious diseases. Previous studies have shown the antiadhesion activity of juice from cultivated cranberries (Vaccinium macrocarpon Ait.) against bacteria, especially E. coli. In this study, the binding of two streptococcal strains, Streptococcus pneumoniae and Streptococcus agalactiae, to molecular size fractions (FI, FII and FIII, <10 kDa, 10-100 kDa, and >100 kDa, respectively) of berries and berry and fruit juices from 12 plant species were studied using a microtiter well assay. For Streptococcus suis a hemagglutination inhibition assay was used. In general, binding activity was detected especially to wild cranberry (Vaccinium oxycoccos L.) and to other Vaccinium species. S. pneumoniae cells bound most to cranberry juice fraction FI and S. agalactiae cells to cranberry fraction FIII. Hemagglutination induced by S. suis was most effectively inhibited by cranberry fraction FII. NMR spectra of some characteristic active and non-active fractions were also measured. They indicate that fractions FII and FIII contained proanthocyanidins and/or other phenolic compounds. The results suggest Vaccinium berries as possible sources of antiadhesives against bacterial infections.

Novel Anti-Adhesive CMC-PE Hydrogel Significantly Enhanced Morphological and Physiological Recovery after Surgical Decompression in an Animal Model of Entrapment Neuropathy.

PubMed

Urano, Hideki; Iwatsuki, Katsuyuki; Yamamoto, Michiro; Ohnisi, Tetsuro; Kurimoto, Shigeru; Endo, Nobuyuki; Hirata, Hitoshi

2016-01-01

We developed a novel hydrogel derived from sodium carboxymethylcellulose (CMC) in which phosphatidylethanolamine (PE) was introduced into the carboxyl groups of CMC to prevent perineural adhesions. This hydrogel has previously shown excellent anti-adhesive effects even after aggressive internal neurolysis in a rat model. Here, we confirmed the effects of the hydrogel on morphological and physiological recovery after nerve decompression. We prepared a rat model of chronic sciatic nerve compression using silicone tubing. Morphological and physiological recovery was confirmed at one, two, and three months after nerve decompression by assessing motor conduction velocity (MCV), the wet weight of the tibialis anterior muscle and morphometric evaluations of nerves. Electrophysiology showed significantly quicker recovery in the CMC-PE group than in the control group (24.0 ± 3.1 vs. 21.0± 2.1 m/s (p < 0.05) at one months and MCV continued to be significantly faster thereafter. Wet muscle weight at one month significantly differed between the CMC-PE (BW) and control groups (0.148 ± 0.020 vs. 0.108 ± 0.019%BW). The mean wet muscle weight was constantly higher in the CMC-PE group than in the control group throughout the experimental period. The axon area at one month was twice as large in the CMC-PE group compared with the control group (24.1 ± 17.3 vs. 12.3 ± 9 μm2) due to the higher ratio of axons with a larger diameter. Although the trend continued throughout the experimental period, the difference decreased after two months and was not statistically significant at three months. Although anti-adhesives can reduce adhesion after nerve injury, their effects on morphological and physiological recovery after surgical decompression of chronic entrapment neuropathy have not been investigated in detail. The present study showed that the new anti-adhesive CMC-PE gel can accelerate morphological and physiological recovery of nerves after decompression surgery.

Dosage effect on uropathogenic Escherichia coli anti-adhesion activity in urine following consumption of cranberry powder standardized for proanthocyanidin content: a multicentric randomized double blind study

PubMed Central

2010-01-01

Background Ingestion of cranberry (Vaccinium macrocarpon Ait.) has traditionally been utilized for prevention of urinary tract infections. The proanthocyanidins (PACs) in cranberry, in particular the A-type linkages have been implicated as important inhibitors of primarily P-fimbriated E. coli adhesion to uroepithelial cells. Additional experiments were required to investigate the persistence in urine samples over a broader time period, to determine the most effective dose per day and to determine if the urinary anti-adhesion effect following cranberry is detected within volunteers of different origins. Methods Two separate bioassays (a mannose-resistant hemagglutination assay and an original new human T24 epithelial cell-line assay) have assessed the ex-vivo urinary bacterial anti-adhesion activity on urines samples collected from 32 volunteers from Japan, Hungary, Spain and France in a randomized, double-blind versus placebo study. An in vivo Caenorhabditis elegans model was used to evaluate the influence of cranberry regimen on the virulence of E. coli strain. Results The results indicated a significant bacterial anti-adhesion activity in urine samples collected from volunteers that consumed cranberry powder compared to placebo (p < 0.001). This inhibition was clearly dose-dependent, prolonged (until 24 h with 72 mg of PAC) and increasing with the amount of PAC equivalents consumed in each cranberry powder regimen. An in vivo Caenorhabditis elegans model showed that cranberry acted against bacterial virulence: E. coli strain presented a reduced ability to kill worms after a growth in urines samples of patients who took cranberry capsules. This effect is particularly important with the regimen of 72 mg of PAC. Conclusions Administration of PAC-standardized cranberry powder at dosages containing 72 mg of PAC per day may offer some protection against bacterial adhesion and virulence in the urinary tract. This effect may offer a nyctohemeral protection. PMID:20398248

Cleaved high-molecular-weight kininogen inhibits neointima formation following vascular injury.

PubMed

Daniel, Jan-Marcus; Reich, Fabian; Dutzmann, Jochen; Weisheit, Simona; Teske, Rebecca; Gündüz, Dursun; Bauersachs, Johann; Preissner, Klaus T; Sedding, Daniel G

2015-08-31

Cleaved high-molecular-weight kininogen (HKa) or its peptide domain 5 (D5) alone exert anti-adhesive properties in vitro related to impeding integrin-mediated cellular interactions. However, the anti-adhesive effects of HKa in vivo remain elusive. In this study, we investigated the effects of HKa on leukocyte recruitment and neointima formation following wire-induced injury of the femoral artery in C57BL/6 mice. Local application of HKa significantly reduced the accumulation of monocytes and also reduced neointimal lesion size 14 days after injury. Moreover, C57BL/6 mice transplanted with bone marrow from transgenic mice expressing enhanced green fluorescence protein (eGFP) showed a significantly reduced accumulation of eGFP+-cells at the arterial injury site and decreased neointimal lesion size after local application of HKa or the polypeptide D5 alone. A differentiation of accumulating eGFP+-cells into highly specific smooth muscle cells (SMC) was not detected in any group. In contrast, application of HKa significantly reduced the proliferation of locally derived neointimal cells. In vitro, HKa and D5 potently inhibited the adhesion of SMC to vitronectin, thus impairing their proliferation, migration, and survival rates. In conclusion, application of HKa or D5 decreases the inflammatory response to vascular injury and exerts direct effects on SMC by impeding the binding of integrins to extracellular matrix components. Therefore, HKa and D5 may hold promise as novel therapeutic substances to prevent neointima formation.

Stopping bacterial adhesion: a novel approach to treating infections.

PubMed

Bavington, C; Page, C

2005-01-01

Adhesion and colonization are prerequisites for the establishment of bacterial pathogenesis. The prevention of adhesion is an attractive target for the development of new therapies in the prevention of infection. Bacteria have developed a multiplicity of adhesion mechanisms commonly targeting surface carbohydrate structures, but our ability to rationally design effective antiadhesives is critically affected by the limitations of our knowledge of the human 'glycome' and of the bacterial function in relation to it. The potential for the future development of carbohydrate-based antiadhesives has been demonstrated by a significant number of in vitro and in vivo studies. Such therapies will be particularly relevant for infections of mucosal surfaces where topical application or delivery is possible. (c) 2005 S. Karger AG, Basel

Microbial biosurfactants as additives for food industries.

PubMed

Campos, Jenyffer Medeiros; Stamford, Tânia Lúcia Montenegro; Sarubbo, Leonie Asfora; de Luna, Juliana Moura; Rufino, Raquel Diniz; Banat, Ibrahim M

2013-01-01

Microbial biosurfactants with high ability to reduce surface and interfacial surface tension and conferring important properties such as emulsification, detergency, solubilization, lubrication and phase dispersion have a wide range of potential applications in many industries. Significant interest in these compounds has been demonstrated by environmental, bioremediation, oil, petroleum, food, beverage, cosmetic and pharmaceutical industries attracted by their low toxicity, biodegradability and sustainable production technologies. Despite having significant potentials associated with emulsion formation, stabilization, antiadhesive and antimicrobial activities, significantly less output and applications have been reported in food industry. This has been exacerbated by uneconomical or uncompetitive costing issues for their production when compared to plant or chemical counterparts. In this review, biosurfactants properties, present uses and potential future applications as food additives acting as thickening, emulsifying, dispersing or stabilising agents in addition to the use of sustainable economic processes utilising agro-industrial wastes as alternative substrates for their production are discussed. © 2013 American Institute of Chemical Engineers.

Co-immobilization of Palm and DNase I for the development of an effective anti-infective coating for catheter surfaces.

PubMed

Alves, Diana; Magalhães, Andreia; Grzywacz, Daria; Neubauer, Damian; Kamysz, Wojciech; Pereira, Maria Olívia

2016-10-15

Biomaterial-associated infections, in particular, catheter-associated infections (CAI) are a major problem in clinical practice due to their ability to resist antimicrobial treatment and the host immune system. This study aimed to co-immobilize the antimicrobial lipopeptide Palm and the enzyme DNase I to introduce both antimicrobial and anti-adhesive functionalities to polydimethylsiloxane (PDMS) material, using dopamine chemistry. Surface characterization confirmed the immobilization of both compounds and no leaching of Palm from the surfaces for up to 5days. Co-immobilization of both agents resulted in a bifunctional coating with excellent surface antimicrobial and anti-biofilm properties against both Staphylococcus aureus and Pseudomonas aeruginosa. The modified surfaces demonstrated superior biocompatibility. To better discriminate co-adhesion of both species on modified surfaces, PNA FISH (Fluorescence in situ hybridization using peptide nucleic acid probes) was employed, and results showed that P. aeruginosa was the dominant organism, with S. aureus adhering afterwards on P. aeruginosa agglomerates. Furthermore, Palm immobilization exhibited no propensity to develop bacterial resistance, as opposite to the immobilization of an antibiotic. The overall results highlighted that co-immobilization of Palm and DNase I holds great potential to be applied in the development of catheters. Catheter-associated infections (CAI) are the most common hospital-acquired infections worldwide. Several coating strategies have been proposed to fight these infections but most of them present some important limitations, including the emergence of resistant bacteria and toxicity concerns. The present work describes a two-step polydopamine-based surface modification strategy to successfully co-immobilize an antimicrobial peptide (Palm) and an enzyme targeting an important component of biofilm matrix (DNase I). This immobilization approach imparted polydimethylsiloxane surfaces with both anti-adhesive and antimicrobial properties against the adhesion of relevant bacteria as single and dual-species, with excellent stability and biocompatible and anti-biofilm properties, holding, therefore, great potential in the development of catheters able to prevent CAI. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Alpinia katsumadai Extracts Inhibit Adhesion and Invasion of Campylobacter jejuni in Animal and Human Foetal Small Intestine Cell Lines.

PubMed

Pogačar, Maja Šikić; Klančnik, Anja; Bucar, Franz; Langerholc, Tomaž; Možina, Sonja Smole

2015-10-01

Alpinia katsumadai is used in traditional Chinese medicine for abdominal distention, pain, and diarrhoea. Campylobacter jejuni is the most common cause of bacterial food-borne diarrhoeal illnesses worldwide. Adhesion to gut epithelium is a prerequisite in its pathogenesis. The antimicrobial, cytotoxic, and anti-adhesive activities of a chemically characterised extract (SEE) and its residual material of hydrodistillation (hdSEE-R) from A. katsumadai seeds were evaluated against C. jejuni. Minimal inhibitory concentrations for SEE and hdSEE-R were 0.5 mg/mL and 0.25 mg/mL, respectively, and there was no cytotoxic influence in the anti-adhesion tests, as these were performed at much lower concentrations of these tested plant extracts. Adhesion of C. jejuni to pig (PSI) and human foetal (H4) small-intestine cell lines was significantly decreased at lower concentrations (0.2 to 50 µg/mL). In the same concentration range, the invasiveness of C. jejuni in PSI cells was reduced by 45% to 65% when they were treated with SEE or hdSEE-R. The hdSEE-R represents a bioactive waste with a high phenolic content and an anti-adhesive activity against C. jejuni and thus has the potential for use in pharmaceutical and food products. Copyright © 2015 John Wiley & Sons, Ltd.

Antiadhesive effect of bioresorbable polylactide film in abraded middle ear mucosa.

PubMed

Jang, Chul Ho; Jo, Si Young; Cho, Yong Beom; Choi, Cheol Hee; Jung, Won Kyo

2014-12-01

Polylactide film (PLF) is used to prevent postoperative peridural adhesion in spinal surgery. Up until now, the antiadhesive effect of bioresorbable PLF in ear middle surgery has not been reported. The purpose of this study is to evaluate the antiadhesive effect of PLF in guinea pigs serving as a model for middle ear mucosal trauma. The animals were divided into two groups: the PLF group and the silastic sheeting group. There were seven guinea pigs (fourteen ears) in both groups. Under aseptic conditions, the middle ear mucosa was abraded using a pick inserted transbullaly. A PLF or silicone sheet was then placed into the guinea pigs' middle ear cavities. The auditory brainstem responses (ABRs) were assessed preoperatively and at three weeks postoperatively while the animals were under general anesthesia. A histopathological study was performed 3 weeks after the operation. The difference between the ABR results before the operation and three weeks postoperatively were not statistically significant. The adhesion formation did not appeared in either group. Prominent fibrous capsule formation and inflammation were observed in the silastic sheeting group, but not in the PLF group. Mild fibrous thickening of regenerated mucosa was observed in the PLF group. From our results, bioresorbable PLF is nonototoxic and biocompatible with the guinea pig's middle ear cavity by short-term evaluation. Further long-term evaluation study is necessary before clinical application. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Amino acids and peptides. XXXII: A bifunctional poly(ethylene glycol) hybrid of fibronectin-related peptides.

PubMed

Maeda, M; Izuno, Y; Kawasaki, K; Kaneda, Y; Mu, Y; Tsutsumi, Y; Lem, K W; Mayumi, T

1997-12-18

An amino acid type poly(ethylene glycol) (aaPPEG) was prepared and its application to a drug carrier was examined. The peptides, Arg-Gly-Asp (RGD) and Glu-Ile-Leu-Asp-Val (EILDV) which were reported as active fragments of Fibronectin (a cell adhesion protein), were conjugated with aaPEG (molecular weight, 10,000). The hybrid, RGD-aaPEG-EILDV, was prepared by a combination of the solid-phase method and the solution method. Antiadhesive activity of the peptides was not lost by its hybrid formation with the large aaPEG molecule. A mixture of RGD (0.43 mmol) and EILDV (0.43 mmol) did not demonstrate an antiadhesive effect, but the hybrid containing 0.43 mmol of each peptide did exhibit this effect.

In vitro anti-bacterial and anti-adherence effects of Lactobacillus delbrueckii subsp bulgaricus on Escherichia coli

PubMed Central

Abedi, D.; Feizizadeh, S.; Akbari, V.; Jafarian-Dehkordi, A.

2013-01-01

Considering the emergence of antibiotic resistance, scientists are interested in using new antimicrobial agents in the treatment of infectious diseases including infections of the enteric systems. Lactic acid bacteria have the great potential to produce antimicrobial compounds that inhibit and control pathogenic bacteria. The aim of this study was to determine the anti-bacterial and anti-adherence properties of Lactobacillus delbrueckii subsp bulgaricus against Escherichia coli. The antibacterial activity of L. delbrueckii was investigated using disc diffusion and spot on lawn methods. In vitro anti-adhesion effect of L. delbrueckii against E. coli was examined using Caco-2 cells. In anti-adhesion assay, three competition conditions including competitive inhibition, adhesion inhibition, and displacement were examined. In spot on lawn method the zone of growth inhibition of E. coli by L. delbrueckii was 21.1 mm. The cell free supernatant of L. delbrueckii showed a good antibacterial activity against E. coli which was mainly related to lactic acid produced by L. delbrueckii. When two bacteria added simultaneously (competitive inhibition) degree of inhibition of E. coli binding by L. delbrueckii was 77%. In adhesion inhibition assay, L. delbrueckii was able to exclude E. coli adherence by around 43.5%. Displacement assay showed that L. delbrueckii had strong displacement ability toward E. coli and reduction of E. coli attachment by bound L. delbrueckii was 81.3%. The results suggest that L. delbrueckii may be able to inhibit E. coli infection in the gut; however more studies including in vivo studies need to be performed. PMID:24082895

Long-term drug release from electrospun fibers for in vivo inflammation prevention in the prevention of peritendinous adhesions.

PubMed

Hu, Changmin; Liu, Shen; Zhang, Yang; Li, Bin; Yang, Huilin; Fan, Cunyi; Cui, Wenguo

2013-07-01

Physical barriers such as electrospun fibrous membranes are potentially useful in preventing peritendinous adhesions after surgery. However, inflammatory responses caused by degradation of barrier materials remain a major challenge. This study aimed to fabricate electrospun composite fibrous membranes based on drug-loaded modified mesoporous silica (MMS) and poly (l-lactic acid) (PLLA). Using a co-solvent-based electrospinning method ibuprofen (IBU)-loaded MMS was successfully and uniformly encapsulated in the PLLA fibers. The electrospun PLLA-MMS-IBU composite fibrous membranes showed significantly lower initial burst release (6% release in the first 12h) compared with that of electrospun PLLA-IBU fibrous membranes (46% release in the first 12h) in in vitro release tests. Moreover, the release from PLLA-MMS-IBU was also for significantly longer than that from PLLA-IBU (100 vs. 20days). In animal studies both PLLA-IBU and PLLA-MMS-IBU showed improved anti-adhesion properties and anti-inflammatory effects compared with PLLA fibrous membrane alone 4weeks after implantation. Further, animals implanted with PLLA-MMS-IBU for 8weeks showed the lowest inflammation and best recovery compared with those implanted with PLLA-IBU and PLLA, most likely as a result of its long-term IBU release profile. Therefore, this study provides a platform technique for fabricating fibrous membranes with long-term sustained drug release characteristics which may function as a novel carrier for long-term anti-inflammation and anti-adhesion to prevent peritendinous adhesions. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Thrombin Cleavage of Plasmodium falciparum Erythrocyte Membrane Protein 1 Inhibits Cytoadherence

PubMed Central

Gillrie, Mark R.; Renaux, Bernard; Russell-Goldman, Eleanor; Avril, Marion; Brazier, Andrew J.; Mihara, Koichiro; Di Cera, Enrico; Milner, Danny A.; Hollenberg, Morley D.; Smith, Joseph D.

2016-01-01

ABSTRACT Plasmodium falciparum malaria remains one of the most deadly infections worldwide. The pathogenesis of the infection results from the sequestration of infected erythrocytes (IRBC) in vital organs, including the brain, with resulting impairment of blood flow, hypoxia, and lactic acidosis. Sequestration occurs through the adhesion of IRBC to host receptors on microvascular endothelium by Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), a large family of variant surface antigens, each with up to seven extracellular domains that can bind to multiple host receptors. Consequently, antiadhesive therapies directed at single endothelial adhesion molecules may not be effective. In this study, we demonstrated that the serine protease thrombin, which is pivotal in the activation of the coagulation cascade, cleaved the major parasite adhesin on the surface of IRBC. As a result, adhesion under flow was dramatically reduced, and already adherent IRBC were detached. Thrombin cleavage sites were mapped to the Duffy binding-like δ1 (DBLδ1) domain and interdomains 1 and 2 in the PfEMP1 of the parasite line IT4var19. Furthermore, we observed an inverse correlation between the presence of thrombin and IRBC in cerebral malaria autopsies of children. We investigated a modified (R67A) thrombin and thrombin inhibitor, hirugen, both of which inhibit the binding of substrates to exosite I, thereby reducing its proinflammatory properties. Both approaches reduced the barrier dysfunction induced by thrombin without affecting its proteolytic activity on PfEMP1, raising the possibility that thrombin cleavage of variant PfEMP1 may be exploited as a broadly inhibitory antiadhesive therapy. PMID:27624125

In vitro anti-bacterial and anti-adherence effects of Lactobacillus delbrueckii subsp bulgaricus on Escherichia coli.

PubMed

Abedi, D; Feizizadeh, S; Akbari, V; Jafarian-Dehkordi, A

2013-10-01

Considering the emergence of antibiotic resistance, scientists are interested in using new antimicrobial agents in the treatment of infectious diseases including infections of the enteric systems. Lactic acid bacteria have the great potential to produce antimicrobial compounds that inhibit and control pathogenic bacteria. The aim of this study was to determine the anti-bacterial and anti-adherence properties of Lactobacillus delbrueckii subsp bulgaricus against Escherichia coli. The antibacterial activity of L. delbrueckii was investigated using disc diffusion and spot on lawn methods. In vitro anti-adhesion effect of L. delbrueckii against E. coli was examined using Caco-2 cells. In anti-adhesion assay, three competition conditions including competitive inhibition, adhesion inhibition, and displacement were examined. In spot on lawn method the zone of growth inhibition of E. coli by L. delbrueckii was 21.1 mm. The cell free supernatant of L. delbrueckii showed a good antibacterial activity against E. coli which was mainly related to lactic acid produced by L. delbrueckii. When two bacteria added simultaneously (competitive inhibition) degree of inhibition of E. coli binding by L. delbrueckii was 77%. In adhesion inhibition assay, L. delbrueckii was able to exclude E. coli adherence by around 43.5%. Displacement assay showed that L. delbrueckii had strong displacement ability toward E. coli and reduction of E. coli attachment by bound L. delbrueckii was 81.3%. The results suggest that L. delbrueckii may be able to inhibit E. coli infection in the gut; however more studies including in vivo studies need to be performed.

A bioabsorbable membrane (Seprafilm®) may prevent postoperative mediastinal adhesions following mediastinoscopy: an experimental study in rats.

PubMed

Büyükkale, Songül; Çıtak, Necati; İşgörücü, Özgür; Sayar, Adnan

2015-01-01

The aim of this experimental study was to investigate the anti-adhesion property of a bioabsorbable membrane following mediastinoscopy in a rat model. The study was conducted in 20 male Sprague-Dawley rats. Mediastinoscopy was performed all of them. Rats were divided into two groups; control group (n=10); mediastinoscopy alone, study group (n=10); mediastinoscopy and sodiumhyaluronate-carboxymethlycellulose film (Seprafilm®; Genzyme Corporation, Cambridge, Mass. USA). It was used to the mediastinal surface at the end of the surgical procedure in study group. Re-mediastinoscopy was performed after 7 days. Adhesion and vascularity grade description scores were analyzed. The parameters evaluated were presence of polymorhphonucleer leucocyte, macrophage, lymphocyte, fibroblasts, edema, neovascularisation, collagenisation, and foreing body reaction. All the rats survived uneventfully until being sacrificed without any postoperative complications. The mean adhesion score was found to be significantly higher in control group (n=2.5±0.5) compared with study group (n=1.0±0.1) (P=0.007). Vascularity grade description score was significantly higher in control group (n=2.3±0.6) than in study group (n=1.4±0.6) (P=0.009). There were no statistical differences between the groups with regard to edema, lymphocyte and macrophage infiltration, fibroblast proliferation and foreign body reactions (P>0.05). The used of Seprafilm® during the primary procedure can reduce to the mediastinal adhesions. However, further studies are required to assess the precise impact of the anti-adhesive agents on adhesion.

Polymeric mannosides prevent DC-SIGN-mediated cell-infection by cytomegalovirus.

PubMed

Brument, S; Cheneau, C; Brissonnet, Y; Deniaud, D; Halary, F; Gouin, S G

2017-09-20

Human cytomegalovirus (HCMV) is a beta-herpesvirus with a high prevalence in the population. HCMV is asymptomatic for immunocompetent adults but is a leading cause of morbidity for new born and immunocompromised patients. It was recently shown that the envelope glycoprotein B (gB) of HCMV interacts with the Dendritic Cell-Specific ICAM-3 Grabbing Non integrin (DC-SIGN) to infect the host. In this work we developed a set of DC-SIGN blockers based on mono-, di-, tetra and polyvalent mannosides. The multivalent mannosides were designed to interact with the carbohydrate recognition domains of DC-SIGN in a chelate or bind and recapture process, and represent the first chemical antiadhesives of HCMV reported so far. Polymeric dextrans coated with triazolylheptylmannoside (THM) ligands were highly potent, blocking the gB and DC-SIGN interaction at nanomolar concentrations. The compounds were further assessed for their ability to prevent the DC-SIGN mediated HCMV infection of dendritic cells. A dextran polymer coated with an average of 902 THM ligands showed an outstanding effect in blocking the HCMV trans-infection with IC 50 values down to the picomolar range (nanomolar when expressed in THM concentration). Each THM moiety on the polymer surpassed the antiadhesive effect of the methylmannoside reference by more than four orders of magnitude. The compound proved non-cytotoxic at the high concentration of 2 mM and therefore represents an interesting antiadhesive candidate against HCMV and potentially against other virus hijacking dendritic cells to infect the host.

Postoperative anti-adhesion ability of a novel carboxymethyl chitosan from silkworm pupa in a rat cecal abrasion model.

PubMed

Zhu, Lin; Zhang, Yu-Qing

2016-04-01

N,O-Carboxymethyl chitosan (NOCC) can prevent postsurgical adhesion formation. Here, we described the preparation of a novel silkworm pupa NOCC and its effects on the prevention of postoperative adhesion in a rat cecal abrasion model. The degree of deacetylation (DDA) of silkworm pupa chitosan was only 49.87 ± 0.86%; regardless, it was used as the raw material to construct the novel silkworm pupa NOCC, which had a weaker crystallinity than the NOCC standard. Sixty male Sprague-Dawley rats were divided into three groups and treated as follows: 0.9% normal saline solution as a negative control, medical anti-adhesion gel as a positive control and the silkworm pupa NOCC anti-adhesion solution. Two and three weeks after surgery, the animals were killed and the adhesion formation was scored. The silkworm pupa NOCC solution significantly decreased the levels of WBC, TNF-α, IL-1β, IL-2, IL-6 and IL-8 but had no effect on IL-4. Additionally, a lower level of TGF-β1 expression was found in the silkworm pupa NOCC group, and significantly less collagen (P<0.01) and fewer inflammatory cells and fibroblasts were detected in the animals of this group. These results suggested that the novel NOCC from silkworm pupa using the method described here have potential applications in the prevention of postoperative intestinal adhesion. Copyright © 2015 Elsevier B.V. All rights reserved.

Antagonistics against pathogenic Bacillus cereus in milk fermentation by Lactobacillus plantarum ZDY2013 and its anti-adhesion effect on Caco-2 cells against pathogens.

PubMed

Zhang, Zhihong; Tao, Xueying; Shah, Nagendra P; Wei, Hua

2016-04-01

Lactobacillus plantarum ZDY2013 is a potential probiotic isolated from fermented bean acid. In this study, we aimed to evaluate the in vitro antimicrobial activity of this organism against Bacillus cereus in milk fermentation, the antiadhesion ability on intestinal epithelial cells, as well as its ability to abrogate the cytotoxic effect and expression levels of genes. We found no antimicrobial activity produced by L. plantarum once the pH was adjusted to 6.0 and 7.0. The pH decreased continuously when L. plantarum and B. cereus were co-incubated during milk fermentation, which caused a decrease in the B. cereus counts. Antiadhesion assays showed that L. plantarum can significantly inhibit the adhesion of enterotoxin-producing B. cereus ATCC14579 and pathogenic B. cereus HN001 by inhibition, competition, and displacement. The supernatants of B. cereus, either alone or in conjunction with L. plantarum, caused damage to the membrane integrity of Caco-2 cells to release lactate dehydrogenase. In addition, L. plantarum tended to attenuate proinflammatory cytokine and oxidative stress gene expression on Caco-2 cells, inducing with B. cereus HN001 supernatants. This study provided systematic insights into the antagonistic effect of L. plantarum ZDY2013, and the information may be helpful to explore potential control measures for preventing food poisoning by lactic acid bacteria. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A review of the biomaterials technologies for infection-resistant surfaces.

PubMed

Campoccia, Davide; Montanaro, Lucio; Arciola, Carla Renata

2013-11-01

Anti-infective biomaterials need to be tailored according to the specific clinical application. All their properties have to be tuned to achieve the best anti-infective performance together with safe biocompatibility and appropriate tissue interactions. Innovative technologies are developing new biomaterials and surfaces endowed with anti-infective properties, relying either on antifouling, or bactericidal, or antibiofilm activities. This review aims at thoroughly surveying the numerous classes of antibacterial biomaterials and the underlying strategies behind them. Bacteria repelling and antiadhesive surfaces, materials with intrinsic antibacterial properties, antibacterial coatings, nanostructured materials, and molecules interfering with bacterial biofilm are considered. Among the new strategies, the use of phages or of antisense peptide nucleic acids are discussed, as well as the possibility to modulate the local immune response by active cytokines. Overall, there is a wealth of technical solutions to contrast the establishment of an implant infection. Many of them exhibit a great potential in preclinical models. The lack of well-structured prospective multicenter clinical trials hinders the achievement of conclusive data on the efficacy and comparative performance of anti-infective biomaterials. © 2013 Elsevier Ltd. All rights reserved.

Visible and UV-curable chitosan derivatives for immobilization of biomolecules.

PubMed

Kim, Eun-Hye; Han, Ga-Dug; Kim, Jae-Won; Noh, Seung-Hyun; Lee, Jae-Gwan; Ito, Yoshihiro; Son, Tae-Il

2017-11-01

Chitosan, which has many biocompatible properties, is used widely in medical field like wound healing, drug delivery and so on. Chitosan could be used as a biomaterial to immobilize protein-drug. There are many methods to immobilize protein-drug, but they have some drawbacks such as low efficiency and denaturation of protein. Therefore, photo-immobilization method is suggested to immobilize protein-drug. Photo-immobilization method is simple-reaction and also needs no additional crosslinking reagent. There has been some effort to modify chitosan to have an ability of photo-immobilization. Generally, visible and UV light reactive chitosan derivatives were prepared. Various types of photo-curable chitosan derivatives showed possibility for application to medical field. For example, they showed ability for protein-immobilization and some of them showed wound-healing effect, anti-adhesive effect, or property to interact directly with titanium surface. In this study, we introduce many types of photo-curable chitosan derivative and their possibility of medical application. Copyright © 2017 Elsevier B.V. All rights reserved.

Current and emerging biologics for ulcerative colitis.

PubMed

Park, Sung Chul; Jeen, Yoon Tae

2015-01-01

Conventional medical treatment for ulcerative colitis can have limited efficacy or severe adverse reactions requiring additional treatment or colectomy. Hence, different biological agents that target specific immunological pathways are be-ing investigated for treating ulcerative colitis. Anti-tumor necrosis factor (TNF) agents were the first biologics to be used for treating inflammatory bowel disease. For example, infliximab and adalimumab, which are anti-TNF agents, are be-ing used for treating ulcerative colitis. Recently, golimumab, another anti-TNF agent, and vedolizumab, an anti-adhesion therapy, have been approved for ulcerative colitis by the U.S. Food and Drug Administration. In addition, new medications such as tofacitinib, a Janus kinase inhibitor, and etrolizumab, another anti-adhesion therapy, are emerging as therapeutic agents. Therefore, there is a need for further studies to select appropriate patient groups for these biologics and to improve the outcomes of ulcerative colitis treatment through appropriate medical usage.

Inhibition of Oral Pathogens Adhesion to Human Gingival Fibroblasts by Wine Polyphenols Alone and in Combination with an Oral Probiotic.

PubMed

Esteban-Fernández, Adelaida; Zorraquín-Peña, Irene; Ferrer, Maria D; Mira, Alex; Bartolomé, Begoña; González de Llano, Dolores; Moreno-Arribas, M Victoria

2018-03-07

Several benefits have been described for red wine polyphenols and probiotic strains in the promotion of colonic metabolism and health. On the contrary, knowledge about their role in the management of oral health is still scarce. In this work, the antiadhesive capacity of selected red wine polyphenols and oenological extracts against the oral pathogens Porphyromonas gingivalis, Fusobacterium nucleatum, and Streptococcus mutans in an in vitro model of human gingival fibroblasts has been explored as well as their complementary action with the candidate oral probiotic Streptococcus dentisani. Results highlighted the antiadhesive capacity of caffeic and p-coumaric acids as well as grape seed and red wine oenological extracts. Both, caffeic and p-coumaric acids increased their inhibition potential against S. mutans adhesion when combined with S. dentisani. Additionally, UHPLC-MS/MS analysis demonstrated the oral metabolism of wine phenolics due to both, cellular and bacterial activity.

Chemical characterization and complement fixation of pectins from Cola cordifolia leaves.

PubMed

Austarheim, Ingvild; Christensen, Bjørn E; Aas, Hoai Thi Nguyen; Thöle, Christian; Diallo, Drissa; Paulsen, Berit S

2014-02-15

Defatted leaves from the medicinal tree Cola cordifolia were extracted with 50% EtOH, 50 °C and 100 °C water. The polysaccharide rich extracts were fractionated and the structure of the polysaccharides elucidated. Linkage analysis of the polysaccharides indicates a rhamnogalacturonan type I backbone where both Rha and parts of GalA are substituted in position 3, indicating a highly branched polymer with short side chains. The purified fractions were tested for complement fixation, macrophage stimulating activity and anti-adhesion activity towards Helicobacter pylori. Here we report on complex and polydisperse types of pectins (Mw: 3-1300 kDa) as well as the presence of low Mw (<3 kDa) acidic oligosaccharides. The fractions showed a moderate complement fixing activity and no macrophage activating effects after LPS removal. Anti-adhesion activity towards H. pylori was not found. Copyright © 2013 Elsevier Ltd. All rights reserved.

Current and Emerging Biologics for Ulcerative Colitis

PubMed Central

Park, Sung Chul; Jeen, Yoon Tae

2015-01-01

Conventional medical treatment for ulcerative colitis can have limited efficacy or severe adverse reactions requiring additional treatment or colectomy. Hence, different biological agents that target specific immunological pathways are being investigated for treating ulcerative colitis. Anti-tumor necrosis factor (TNF) agents were the first biologics to be used for treating inflammatory bowel disease. For example, infliximab and adalimumab, which are anti-TNF agents, are being used for treating ulcerative colitis. Recently, golimumab, another anti-TNF agent, and vedolizumab, an anti-adhesion therapy, have been approved for ulcerative colitis by the U.S. Food and Drug Administration. In addition, new medications such as tofacitinib, a Janus kinase inhibitor, and etrolizumab, another anti-adhesion therapy, are emerging as therapeutic agents. Therefore, there is a need for further studies to select appropriate patient groups for these biologics and to improve the outcomes of ulcerative colitis treatment through appropriate medical usage. PMID:25547087

Role of the endothelial surface layer in neutrophil recruitment.

PubMed

Marki, Alex; Esko, Jeffrey D; Pries, Axel R; Ley, Klaus

2015-10-01

Neutrophil recruitment in most tissues is limited to postcapillary venules, where E- and P-selectins are inducibly expressed by venular endothelial cells. These molecules support neutrophil rolling via binding of PSGL-1 and other ligands on neutrophils. Selectins extend ≤ 38 nm above the endothelial plasma membrane, and PSGL-1 extends to 50 nm above the neutrophil plasma membrane. However, endothelial cells are covered with an ESL composed of glycosaminoglycans that is ≥ 500 nm thick and has measurable resistance against compression. The neutrophil surface is also covered with a surface layer. These surface layers would be expected to completely shield adhesion molecules; thus, neutrophils should not be able to roll and adhere. However, in the cremaster muscle and in many other models investigated using intravital microscopy, neutrophils clearly roll, and their rolling is easily and quickly induced. This conundrum was thought to be resolved by the observation that the induction of selectins is accompanied by ESL shedding; however, ESL shedding only partially reduces the ESL thickness (to 200 nm) and thus is insufficient to expose adhesion molecules. In addition to its antiadhesive functions, the ESL also presents neutrophil arrest-inducing chemokines. ESL heparan sulfate can also bind L-selectin expressed by the neutrophils, which contributes to rolling and arrest. We conclude that ESL has both proadhesive and antiadhesive functions. However, most previous studies considered either only the proadhesive or only the antiadhesive effects of the ESL. An integrated model for the role of the ESL in neutrophil rolling, arrest, and transmigration is needed. © Society for Leukocyte Biology.

Role of the endothelial surface layer in neutrophil recruitment

PubMed Central

Marki, Alex; Esko, Jeffrey D.; Pries, Axel R.; Ley, Klaus

2015-01-01

Neutrophil recruitment in most tissues is limited to postcapillary venules, where E- and P-selectins are inducibly expressed by venular endothelial cells. These molecules support neutrophil rolling via binding of PSGL-1 and other ligands on neutrophils. Selectins extend ≤38 nm above the endothelial plasma membrane, and PSGL-1 extends to 50 nm above the neutrophil plasma membrane. However, endothelial cells are covered with an ESL composed of glycosaminoglycans that is ≥500 nm thick and has measurable resistance against compression. The neutrophil surface is also covered with a surface layer. These surface layers would be expected to completely shield adhesion molecules; thus, neutrophils should not be able to roll and adhere. However, in the cremaster muscle and in many other models investigated using intravital microscopy, neutrophils clearly roll, and their rolling is easily and quickly induced. This conundrum was thought to be resolved by the observation that the induction of selectins is accompanied by ESL shedding; however, ESL shedding only partially reduces the ESL thickness (to 200 nm) and thus is insufficient to expose adhesion molecules. In addition to its antiadhesive functions, the ESL also presents neutrophil arrest-inducing chemokines. ESL heparan sulfate can also bind L-selectin expressed by the neutrophils, which contributes to rolling and arrest. We conclude that ESL has both proadhesive and antiadhesive functions. However, most previous studies considered either only the proadhesive or only the antiadhesive effects of the ESL. An integrated model for the role of the ESL in neutrophil rolling, arrest, and transmigration is needed. PMID:25979432

The influences of a novel anti-adhesion device, thermally cross-linked gelatin film on peritoneal dissemination of tumor cells: The in vitro and in vivo experiments using murine carcinomatous peritonitis models.

PubMed

Miyamoto, Hiroe; Tsujimoto, Hiroyuki; Horii, Tsunehito; Ozamoto, Yuki; Ueda, Joe; Takagi, Toshitaka; Saitoh, Naoto; Hagiwara, Akeo

2017-10-10

To create anti-adhesive materials to be more effective and safer, we developed a thermally cross-linked gelatin film that showed superior anti-adhesive effects with excellent peritoneal regeneration. However, it may act as a convenient scaffold for tumor cell growth, thereby accelerating peritoneal dissemination when used in surgery for abdominal tumors. In this study, we tried to clarify this issue using mouse carcinomatous peritonitis models. First, we examined the in vitro tumor cell growth of mouse B16 melanoma or Colon26 cells on the gelatin film or the conventional hyarulonate/carboxymethylcellulose film. Tumor cell growth on each film was significantly lower than that of the control (no film). Next, we conducted the following in vivo experiments: After the parietal peritoneum was partially removed and covered with each film or without any film, mice were inoculated intraperitoneally with B16 melanoma or Colon26/Nluc cells expressing NanoLuc luciferase gene. At 7 days after the operation, we measured the weight of B16 melanoma tumors or the NanoLuc activity of Colon26/Nluc cells using in vivo imaging at the injured sites. There were no significant differences in the weight of the tumors and the NanoLuc activity among the three groups. We also observed the survival time of mice receiving the same operation and treatments. There was no significant difference in the survival time among the three groups. These results suggest that the gelatin film will likely not accelerate peritoneal dissemination as a convenient scaffold for tumor cell growth when used in surgery for abdominal tumors. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017. © 2017 Wiley Periodicals, Inc.

Efficacy of hyaluronic acid and hydroxyethyl starch in preventing adhesion following endoscopic sinus surgery.

PubMed

Kim, Su-Jong; Shin, Jae-Min; Lee, Eun Jung; Park, Il-Ho; Lee, Heung-Man; Kim, Kyung-Su

2017-10-01

Adhesion is a major complication of endoscopic sinus surgery that may lead to recurrence of chronic rhinosinusitis, necessitating revision surgery. The purpose of this study was to evaluate the effect of hyaluronic acid and hydroxyethyl starch (HA-HES) relative to hyaluronic acid and carboxymethylcellulose (HA-CMC) with regard to anti-adhesion effect. In this multi-center, prospective, single-blind, randomized controlled study, 77 consecutive patients who underwent bilateral endoscopic sinus surgery were enrolled between March 2014 and March 2015. HA-HES and HA-CMC were applied to randomly assigned ethmoidectomized cavities after the removal of middle meatal packing. At the 1st, 2nd and 4th weeks after surgery, the presence and grades of adhesion, edema, and infection were, respectively, examined via endoscopy by a blinded assessor. The incidence and grades of adhesion at the 2-week follow-up were significantly less in the HA-CMC group than in the HA-HES group (p < 0.05). However, with the exception of week 2, there were no significant differences in the incidence or grades of adhesion, edema, and infection between the two groups. When the primary endpoint-the presence of adhesion at the 4-week follow-up-was compared between two groups, the incidence of adhesion in HA-HES group at the 4-week follow-up was 32% and in HA-CMC was 41.3%, indicating that HA-HES was not inferior to HA-CMC in terms of anti-adhesive effect. No severe adverse reactions were noted during the study period. In conclusion, HA-HES is a safe substitutional anti-adhesion agent that has equivalent effect as HA-CMC after endoscopic sinus surgery.

Quick-release medical tape

PubMed Central

Laulicht, Bryan; Langer, Robert; Karp, Jeffrey M.

2012-01-01

Medical tape that provides secure fixation of life-sustaining and -monitoring devices with quick, easy, damage-free removal represents a longstanding unmet medical need in neonatal care. During removal of current medical tapes, crack propagation occurs at the adhesive–skin interface, which is also the interface responsible for device fixation. By designing quick-release medical tape to undergo crack propagation between the backing and adhesive layers, we decouple removal and device fixation, enabling dual functionality. We created an ordered adhesive/antiadhesive composite intermediary layer between the medical tape backing and adhesive for which we achieve tunable peel removal force, while maintaining high shear adhesion to secure medical devices. We elucidate the relationship between the spatial ordering of adhesive and antiadhesive regions to create a fully tunable system that achieves strong device fixation and quick, easy, damage-free device removal. We also described ways of neutralizing the residual adhesive on the skin and have observed that thick continuous films of adhesive are easier to remove than the thin islands associated with residual adhesive left by current medical tapes. PMID:23112196

Cranberry juice for prophylaxis of urinary tract infections--conclusions from clinical experience and research.

PubMed

Nowack, Rainer; Schmitt, Wilhelm

2008-09-01

Cranberry juice (Vaccinium macrocarpon) is a widely used and recommended North-American folk remedy for prophylaxis of urinary tract infections (UTI). Clinical trials have documented its efficacy in women with recurrent UTI, but so far not in other groups of patients. The composition of effective cranberry products and its dosage in UTI prophylaxis have not been defined. Intriguing experimental research has identified an anti-adhesive mechanism of cranberry juice that prevents docking of bacteria on host tissues. This efficacy mechanism can be traced in patients' urine following oral intake of cranberry products and appears to be due to proanthocyanidins with an A-type linkage of flavanols. The application of this anti-adhesion mechanism of cranberry-proanthocyandins is currently also investigated in other common diseases of bacterial pathogenesis, for example Helicobacter pylori-associated gastritis and dental caries/periodontal disease. The use of cranberry products appears to be safe and provide additional benefits by anti-oxidant and cholesterol-lowering activity.

Cranberry xyloglucan structure and inhibition of Escherichia coli adhesion to epithelial cells

USDA-ARS?s Scientific Manuscript database

Cranberry juice has been used to treat urinary tract infections based on scientific reports of proanthocyanidin anti-adhesion activity for Escherichia coli as well as folklore. Xyloglucan oligosaccharides were also detected in cranberry juice and the pulp remaining following commercial juice extract...

96X Screen-Printed Gold Electrode Platform to Evaluate Electroactive Polymers as Marine Antifouling Coatings.

PubMed

Brisset, Hugues; Briand, Jean-François; Barry-Martinet, Raphaëlle; Duong, The Hy; Frère, Pierre; Gohier, Frédéric; Leriche, Philippe; Bressy, Christine

2018-04-17

Several alternatives are currently investigated to prevent and control the natural process of colonization of any seawater submerged surfaces by marine organisms. Since few years we develop an approach based on addressable electroactive coatings containing conducting polymers or polymers with lateral redox groups. In this article we describe the use of a screen-printed plate formed by 96 three-electrode electrochemical cells to assess the potential of these electroactive coatings to prevent the adhesion of marine bacteria. This novel platform is intended to control and record the redox properties of the electroactive coating in each well during the bioassay (15 h) and to allow screening its antiadhesion activity with enough replicates to support significant conclusions. Validation of this platform was carried out with poly(ethylenedioxythiophene) (PEDOT) as electroactive coating obtained by electropolymerization of EDOT monomer in artificial seawater electrolyte on the working electrode of each electrochemical cell of the 96-well microplate.

Fabrication of porous hierarchical polymer/ceramic composites by electron irradiation of organic/inorganic polymers: route to a highly durable, large-area superhydrophobic coating.

PubMed

Lee, Eun Je; Kim, Jae Joon; Cho, Sung Oh

2010-03-02

Polymer/ceramic composite films with micro- and nanocombined hierarchical structures are fabricated by electron irradiation of poly(methyl methacrylate) (PMMA) microspheres/silicone grease. Electron irradiation induces volume contraction of PMMA microspheres and simultaneously transforms silicone grease into a ceramic material of silicon oxycarbide with many nanobumps. As a result, highly porous structures that consist of micrometer-sized pores and microparticles decorated with nanobumps are created. The fabricated films with the porous hierarchical structure exhibit good superhydrophobicity with excellent self-cleaning and antiadhesion properties after surface treatment with fluorosilane. In addition, the porous hierarchical structures are covered with silicon oxycarbide, and thus the superhydrophobic coatings have high hardness and strong adhesion to the substrate. The presented technique provides a straightforward route to producing large-area, mechanically robust superhydrophobic films on various substrate materials.

Evaluation of biocompatibility and toxicity of biodegradable poly (DL-lactic acid) films

PubMed Central

Li, Rui-Yun; Liu, Zhi-Gang; Liu, Huan-Qiu; Chen, Lei; Liu, Jian-Feng; Pan, Yue-Hai

2015-01-01

Regeneration and functional recovery of nerves after peripheral nerve injury is the key to peripheral nerve repair. One of the putative therapeutic strategies is to use anti-adhesion polymer films, made of polymeric biomaterials. Recently, a novel biodegradable poly (DL-lactic acid) (PDLLA) film has been prepared using a method of phase transformation with biodegradable polylactic acid polymer as the substrate. This novel, anti-adhesion film has a porous structure, which provides better mechanical properties, better flexibility, more complete diffusion through the polymer of tissue biologic factors like growth factors, and more controllable degradation compared to traditional non-porous films. Little is known, however, about the in vitro and in vivo biocompatibility and cytotoxicity of this type of PDLLA film. Therefore, our aim was to evaluate the biocompatibility and cytotoxicity of this novel PDLLA film using various experimental methods, including a skin irritation test, MTT analysis, and the mouse bone marrow cell micronucleus test, as well as hematology or clinical chemistry measurements in rats after receiving sciatic nerve transection and anastomosis with wrapping of the anastomosis with DLLA films. We demonstrated that exposure to PDLLA film extracts did not generate apparent erythema or edema in rabbit skin and had no effect on the proliferation of Vero cells. Additionally, treatment with PDLLA film extracts did not alter the incidence of micronucleated polychromatic erythrocytes as compared with saline Treated group. Furthermore, implantation of PDLLA film did not alter liver or renal function as measured by serum levels of ALT, AST, TP, A/G, Cr, and BUN, and pathologic examinations showed that implantation of PDLLA film did not cause pathologic changes to the rat liver, kidney, pancreas, or spleen. Taken together, these results suggest that PDLLA films have excellent biocompatibility and no obvious toxicity in vivo, and may be used to prevent nerve adhesion, thereby promoting nerve regeneration. PMID:26396667

Advances in biomaterials for preventing tissue adhesion.

PubMed

Wu, Wei; Cheng, Ruoyu; das Neves, José; Tang, Jincheng; Xiao, Junyuan; Ni, Qing; Liu, Xinnong; Pan, Guoqing; Li, Dechun; Cui, Wenguo; Sarmento, Bruno

2017-09-10

Adhesion is one of the most common postsurgical complications, occurring simultaneously as the damaged tissue heals. Accompanied by symptoms such as inflammation, pain and even dyskinesia in particular circumstances, tissue adhesion has substantially compromised the quality of life of patients. Instead of passive treatment, which involves high cost and prolonged hospital stay, active intervention to prevent the adhesion from happening has been accepted as the optimized strategy against this complication. Herein, this paper will cover not only the mechanism of adhesion forming, but also the biomaterials and medicines used in its prevention. Apart from acting as a direct barrier, biomaterials also show promising anti-adhesive bioactivity though their intrinsic physical and chemical are still not completely unveiled. Considering the diversity of human tissue organization, it is imperative that various biomaterials in combination with specific medicine could be tuned to fit the microenvironment of targeted tissues. With the illustration of different adhesion mechanism and solutions, we hope this review can become a beacon and further inspires the development of anti-adhesion biomedicines. Copyright © 2017 Elsevier B.V. All rights reserved.

Traditionally used medicinal plants against uncomplicated urinary tract infections: Are unusual, flavan-4-ol- and derhamnosylmaysin derivatives responsible for the antiadhesive activity of extracts obtained from stigmata of Zea mays L. against uropathogenic E. coli and Benzethonium chloride as frequent contaminant faking potential antibacterial activities?

PubMed

Rafsanjany, Nasli; Sendker, Jandirk; Lechtenberg, Matthias; Petereit, Frank; Scharf, Birte; Hensel, Andreas

2015-09-01

The dried stigmata from Zea mays L. are used traditionally for the treatment of uncomplicated urinary tract infections. A recent screening has indicated that hydroalcoholic extract of the herbal material inhibits the adhesion of uropathogenic Escherichia coli (UPEC) to T24 bladder cells. For verification of these data EtOH-water (1:1) extracts from 4 different batches of Maydis stigmata were investigated. Within an in vitro adhesion assay (UPEC strain 2980 and human T24 bladder cells) a dose-dependent antiadhesive activity against UPEC was verified (IC50 1040μg/mL). Bioassay guided fractionation of M. stigmata, batch S1, by EtOH-water extraction, followed by chromatography on Sephadex LH20 revealed two active fractions (I and XI). Further purification of fraction I and structure elucidation of the isolated compound revealed the presence of significant amounts of the biocide benzethonium chloride as contaminant. Benzethonium chloride was also identified in subsequent investigations in 2 different batches of M. stigmata. The presence of such nondeclared and illegal contaminants in the herbal raw material market has to be discussed intensively. From benzethonium-free raw material (batch S2) as well as from batch S1 fraction XI was further fractionated by MPLC and preparative HPLC, leading to a still complex subfraction XIG, which was analyzed by UHPLC/+ESI-QTOF-MS analysis. Advanced data processing and species-metabolite relationship database revealed the tentatively existence of the unusual C-glycosidic flavones derhamnosylmaysin (6), 3'-deoxyrhamnosylmaysin (4), 3'-O-methylderhamnosylmaysin (3), apiferol (2) and alternanthin (8) which might be related to the antiadhesive activity of this subfraction against UPEC. Copyright © 2015 Elsevier B.V. All rights reserved.

Biocompatibility of electrospun human albumin: a pilot study.

PubMed

Noszczyk, B H; Kowalczyk, T; Łyżniak, M; Zembrzycki, K; Mikułowski, G; Wysocki, J; Kawiak, J; Pojda, Z

2015-03-02

Albumin is rarely used for electrospinning because it does not form fibres in its native globular form. This paper presents a novel method for electrospinning human albumin from a solution containing pharmaceutical grade protein and 25% polyethylene oxide (PEO) used as the fibre-forming agent. After spontaneous cross-linking at body temperature, with no further chemicals added, the fibres become insoluble and the excess PEO can be washed out. Albumin deposited along the fibres retains its native characteristics, such as its non-adhesiveness to cells and its susceptibility for degradation by macrophages. To demonstrate this we evaluated the mechanical properties, biocompatibility and biodegradability of this novel product. After subcutaneous implantation in mice, albumin mats were completely resorbable within six days and elicited only a limited local inflammatory response. In vitro, the mats suppressed cell attachment and migration. As this product is inexpensive, produced from human pharmaceutical grade albumin without chemical modifications, retains its native protein properties and fulfils the specific requirements for anti-adhesive dressings, its clinical use can be expedited. We believe that it could specifically be used when treating paediatric patients with epidermolysis bullosa, in whom non-healing wounds occur after minor hand injuries which lead to rapid adhesions and devastating contractures.

Adhesion of Asaia bogorensis to Glass and Polystyrene in the Presence of Cranberry Juice.

PubMed

Antolak, Hubert; Kregiel, Dorota; Czyzowska, Agata

2015-06-01

The aim of the study was to evaluate the adhesion abilities of the acetic acid bacterium Asaia bogorensis to glass and polystyrene in the presence of American cranberry (Vaccinium macrocarpon) juice. The strain of A. bogorensis used was isolated from spoiled commercial fruit-flavored drinking water. The cranberry juice was analyzed for polyphenols, organic acids, and carbohydrates using high-performance liquid chromatography and liquid chromatography-mass spectrometry techniques. The adhesive abilities of bacterial cells in culture medium supplemented with cranberry juice were determined using luminometry and microscopy. The viability of adhered and planktonic bacterial cells was determined by the plate count method, and the relative adhesion coefficient was calculated. This strain of A. bogorensis was characterized by strong adhesion properties that were dependent upon the type of surface. The highest level of cell adhesion was found on the polystyrene. However, in the presence of 10% cranberry juice, attachment of bacterial cells was three times lower. Chemical analysis of juice revealed the presence of sugars, organic acids, and anthocyanins, which were identified as galactosides, glucosides, and arabinosides of cyanidin and peonidin. A-type proanthocyanidins responsible for the antiadhesion properties of V. macrocarpon also were detected.

Comprehensive assessment of the quality of commercial cranberry products. Phenolic characterization and in vitro bioactivity.

PubMed

Sánchez-Patán, Fernando; Bartolomé, Begoña; Martín-Alvarez, Pedro J; Anderson, Mark; Howell, Amy; Monagas, María

2012-04-04

Cranberry (Vaccinium macrocarpon) products have been widely recommended in traditional American medicine for the treatment of urinary tract infection (UTI). A total of 19 different commercial cranberry products from American and European markets have been analyzed by different global phenolic methods and by UPLC-DAD-ESI-TQ MS. In addition, in vitro antioxidant capacity and uropathogenic bacterial antiadhesion activity tests have been performed. Results revealed that products found in the market widely differed in their phenolic content and distribution, including products completely devoid of flavan-3-ols to highly purified ones, either in A-type proanthocyanidins (PACs) or in anthocyanins. The product presentation form and polyphenolic profile widely affected the antiadhesion activity, ranging from a negative (nulel) effect to a MIC = 0.5 mg/mL for cranberry powders and a MIC=112 mg/mL for gel capsule samples. Only 4 of 19 products would provide the recommended dose of intake of 36 mg total PACs/day. Of most importance was the fact that this dose would actually provide as low as 0.00 and up to 205 μg/g of procyanidin A2, indicating the lack of product standardization and incongruence between global and individual compound analysis.

Prevention of Intraabdominal Adhesions: An Experimental Study Using Mitomycin-C and 4% Icodextrin.

PubMed

Urkan, Murat; Özerhan, İsmail Hakkı; Ünlü, Aytekin; Can, Mehmet Fatih; Öztürk, Erkan; Günal, Armağan; Yağcı, Gökhan

2017-01-01

Intraabdominal adhesions remain a significant cause of morbidity and mortality. Moreover, intraabdominal adhesions can develop in more than 50% of abdominal operations. We compared the anti-adhesive effects of two different agents on postoperative adhesion formation in a cecal abrasion model. Experimental animal study. Forty Wistar albino type female rats were anesthetized and underwent laparotomy. Study groups comprised Sham, Control, Mitomycin-C, 4% Icodextrin, and Mitomycin-C +4% Icodextrin groups. Macroscopic and histopathological evaluations of adhesions were performed. The frequencies of moderate and severe adhesions were significantly higher in the control group than the other groups. The mitomycin-C and Mitomycin-C +4% Icodextrin groups were associated with significantly lower adhesion scores compared to the control group and 4% Icodextrin group scores (p=0.002 and p=0.008, respectively). The adhesion scores of the Mitomycin-C group were also significantly lower than those of the 4% Icodextrin group (p=0.008). Despite its potential for bone marrow toxicity, Mitomycin-C seems to effectively prevent adhesions. Further studies that prove an acceptable safety profile relating to this promising anti-adhesive agent are required before moving into clinical trials.

Hyaluronic Acid and Its Composites as a Local Antimicrobial/Antiadhesive Barrier

PubMed Central

Romanò, C.L.; De Vecchi, E.; Bortolin, M.; Morelli, I.; Drago, L.

2017-01-01

Living in biofilms is probably the most common condition for bacteria and fungi and biofilm-related infections account for the majority of bacterial infectious diseases worldwide. Among others biofilm-related infections, those associated with implanted biomaterials have an enormous and still largely underestimated impact in orthopaedics and trauma, cardio-surgery and several other surgical disciplines. Given the limited efficacy of existing antibiotics in the prevention and treatment of bacterial biofilms, new strategies are needed to protect implants and host tissues, overcoming the striking ability of the microorganisms to adhere on different surfaces and to immediately protect themselves by forming the biofilm matrix. Adhesion is a necessary first step in microbial colonization and pathogenesis and provides a potential target for new preventive and treatment approach. Among various polymers, tested as antibacterial coatings, hyaluronic acid and some of its composites do offer a well-established long-term safety profile and a proven ability to reduce bacterial adhesion and biofilm formation. Aim of the present review is to summarize the available evidence concerning the antiadhesion/antibiofilm activity of hyaluronic acid and some of its derivatives to reduce/prevent bacterial adhesion and biofilm formation in various experimental and clinical settings. PMID:28529865

Occupational allergic and irritant contact dermatitis in workers exposed to polyurethane foam.

PubMed

Kieć-Świerczyńska, Marta; Swierczyńska-Machura, Dominika; Chomiczewska-Skóra, Dorota; Nowakowska-Świrta, Ewa; Kręcisz, Beata

2014-04-01

To evaluate sensitization to chemicals present in work environment after an outbreak of contact dermatitis in workers of vehicle equipment factory, exposed to polyurethane foam, based on 4,4'-diphenylmethane diisocyanate (MDI). From among 300 employees, 21 individuals reporting work-related skin and/or respiratory tract symptoms underwent clinical examination, patch testing, skin prick tests, spirometry and MDI sIgE measurement in serum. Patch tests included isocyanates series, selected rubber additives, metals, fragrances, preservatives, and an antiadhesive agent. Clinical examination revealed current eczema in the area of hands and/or forearms in 10 workers. Positive patch test reactions were found in 10 individuals, the most frequent to diaminodiphenylmethane and 4-phenylenediamine (7 persons). Reactions to an antiadhesive agent were assessed as irritant (5 workers). Except for sensitization to common aeroallergens, no significant abnormalities were found in the remaining tests. Occupational allergic contact dermatitis was diagnosed in 7 workers, irritant contact dermatitis in 10 and coexisiting allergic and irritant contact dermatitis in 3 workers. In workers manufacturing products from polyurethane foam, attention should be paid to the risk of developing contact dermatitis. Skin problems in our study group were attributable probably to insufficient protection of the skin.

Adhesion inhibition of F1C-fimbriated Escherichia coli and Pseudomonas aeruginosa PAK and PAO by multivalent carbohydrate ligands.

PubMed

Autar, Reshma; Khan, A Salam; Schad, Matthias; Hacker, Jörg; Liskamp, Rob M J; Pieters, Roland J

2003-12-05

In order to evaluate their inhibition of bacterial adhesion, the carbohydrate sequences GalNAcbeta1-->4Gal and GalNAcbeta1-->4Galbeta1-->4Glc were synthesized. The disaccharide was conjugated to dendrons based on the 3,5-di-(2-aminoethoxy)-benzoic acid branching unit to yield di- and tetravalent versions of these compounds. A divalent compound was also prepared that had significantly longer spacer arms. Relevant monovalent compounds were prepared for comparison. Their anti-adhesion properties against F1C-fimbriated uropathogenic Escherichia coli were evaluated in an ELISA-type assay by using a recombinant strain and also by using Pseudomonas aeruginosa strains PAO and PAK. Adhesion inhibition was observed in all cases, and multivalency effects of up to one order of magnitude were observed. The combination of spacer and multivalency effects led to a 38-fold increase in the potency of a divalent inhibitor with long spacer arms towards the PAO strain when compared with the free carbohydrate.

Biosurfactant production through Bacillus sp. MTCC 5877 and its multifarious applications in food industry.

PubMed

Anjum, Farhan; Gautam, Gunjan; Edgard, Gnansounou; Negi, Sangeeta

2016-08-01

In this study Bacillus sp. MTCC5877 was explored for the production of biosurfactant (BSs) and various carbon sources 1% (w/v), 0.5% (w/v) nitrogen sources were tested at different pH, and temperature. Yield was measured in terms of Emulsification index (EI), Oil Displacement Area (ODA) and Drop Collapse Area (DCA) and maximum emulsification activities of BSs were found (E24) 50%, 76% and 46%, respectively, and maximum ODA of 5.0, 6.2 and 4.7cm, were shown respectively. The BS was able to reduce the surface tension of water from 72 to 30mN/m and 72 to 32mN/m. Structural compositions of BS were confirmed by FTIR, GC-MS and NMR. Anti-adhesive property of BS was determined and found effective against biofilm formation. It could remove 73% Cd from vegetable which confirms its application in food industry. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of hierarchical structures and insulating liquid media on adhesion

NASA Astrophysics Data System (ADS)

Yang, Weixu; Wang, Xiaoli; Li, Hanqing; Song, Xintao

2017-11-01

Effects of hierarchical structures and insulating liquid media on adhesion are investigated through a numerical adhesive contact model established in this paper, in which hierarchical structures are considered by introducing the height distribution into the surface gap equation, and media are taken into account through the Hamaker constant in Lifshitz-Hamaker approach. Computational methods such as inexact Newton method, bi-conjugate stabilized (Bi-CGSTAB) method and fast Fourier transform (FFT) technique are employed to obtain the adhesive force. It is shown that hierarchical structured surface exhibits excellent anti-adhesive properties compared with flat, micro or nano structured surfaces. Adhesion force is more dependent on the sizes of nanostructures than those of microstructures, and the optimal ranges of nanostructure pitch and maximum height for small adhesion force are presented. Insulating liquid media effectively decrease the adhesive interaction and 1-bromonaphthalene exhibits the smallest adhesion force among the five selected media. In addition, effects of hierarchical structures with optimal sizes on reducing adhesion are more obvious than those of the selected insulating liquid media.

Bioinspired polyethylene terephthalate nanocone arrays with underwater superoleophobicity and anti-bioadhesion properties

NASA Astrophysics Data System (ADS)

Liu, Wendong; Liu, Xueyao; Fangteng, Jiaozi; Wang, Shuli; Fang, Liping; Shen, Huaizhong; Xiang, Siyuan; Sun, Hongchen; Yang, Bai

2014-10-01

This paper presents a facile method to fabricate bioinspired polyethylene terephthalate (PET) nanocone arrays via colloidal lithography. The aspect ratio (AR) of the nanocones can be finely modulated ranging from 1 to 6 by regulating the etching time. The samples with the AR value of 6 can present underwater superoleophobicity with the underwater oil contact angle (OCA) of 171.8°. The as-prepared PET nanocone arrays perform anti-bioadhesion behavior, which inhibits the formation of the actin cytoskeleton when it used as the substrate for cell culture. Moreover, the oil wettability is temperature controlled after modifying the PET nanocone arrays with PNIPAAm film, and the oil wettability of the functionalized nanocone arrays can be transformed from the superoleophobic state with OCA about 151° to the oleophilic state with OCA about 25° reversibly. Due to the high-throughput, parallel fabrication and cost-efficiency of this method, it will be favourable for researchers to introduce oleophobic properties to various substrate and device surfaces. Due to the superoleophobicity and simple functionalizing properties, the PET nanocone arrays are very promising surfaces for anti-adhesion, self-cleaning and have potential applications in material, medical, and biological fields.This paper presents a facile method to fabricate bioinspired polyethylene terephthalate (PET) nanocone arrays via colloidal lithography. The aspect ratio (AR) of the nanocones can be finely modulated ranging from 1 to 6 by regulating the etching time. The samples with the AR value of 6 can present underwater superoleophobicity with the underwater oil contact angle (OCA) of 171.8°. The as-prepared PET nanocone arrays perform anti-bioadhesion behavior, which inhibits the formation of the actin cytoskeleton when it used as the substrate for cell culture. Moreover, the oil wettability is temperature controlled after modifying the PET nanocone arrays with PNIPAAm film, and the oil wettability of the functionalized nanocone arrays can be transformed from the superoleophobic state with OCA about 151° to the oleophilic state with OCA about 25° reversibly. Due to the high-throughput, parallel fabrication and cost-efficiency of this method, it will be favourable for researchers to introduce oleophobic properties to various substrate and device surfaces. Due to the superoleophobicity and simple functionalizing properties, the PET nanocone arrays are very promising surfaces for anti-adhesion, self-cleaning and have potential applications in material, medical, and biological fields. Electronic supplementary information (ESI) available: The optical microscopy image of the self-assembled 2D PS microspheres over a large area, the diameter of the PS microsphere is 580 nm; The top-view SEM image of the PET nanocone arrays over a large area, the AR of the nanocone is 6; The SEM image of the PET nanocone arrays obtained after 30 min etching; The optical image of the water droplet on the PET nanocone arrays with an AR of 6; The schematic illustration of the nanocone arrays modification with PNIPAAm; High resolution XPS spectra of the PNIPAAm modified PET nanocone arrays. See DOI: 10.1039/c4nr04471a

Enhancement of antibacterial properties of polyurethanes by chitosan and heparin immobilization

NASA Astrophysics Data System (ADS)

Kara, Filiz; Aksoy, E. Ayse; Yuksekdag, Zehranur; Aksoy, Serpil; Hasirci, Nesrin

2015-12-01

Being antibacterial is a required property for the materials used in medical devices and instruments. Polyurethanes (PUs) are one class of polymers widely used in the production of devices that especially come in contact with blood (e.g. heart valves, blood vessels, vascular grafts and catheters). In this study, hexamethylene diisocyanate based polyurethanes (PUh) were synthesized and antibacterial and anti-adhesive properties were added by immobilizing chitosan (CH) and heparin (Hep) on the samples of PUh via a stepwise process. Chemistry and topography of the modified film samples (PUh-CH and PUh-CH-Hep) were examined by Fourier Transform Infrared Spectrophotometry-Attenuated Total Reflectance (FTIR-ATR), Electron Spectroscopy for Chemical Analysis (ESCA) and Atomic Force Microscopy (AFM), and surface free energy (SFE) values after each step were determined by goniometer. PUh-CH and PUh-CH-Hep samples were found to be antibacterial against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis) (both Gram positive) and Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) (both Gram negative) bacteria, and bacterial adhesion results showed a significant decrease in the number of viable bacteria on both modified samples where PUh-CH-Hep was the most effective. The findings of this study show that polymeric surfaces can be effectively modified and converted to be antibacterial by chitosan and heparin immobilization, and presence of both chemicals enhance efficacy against bacteria.

The use of chitosan-dextran gel shows anti-inflammatory, antibiofilm, and antiproliferative properties in fibroblast cell culture.

PubMed

Paramasivan, Sathish; Jones, Damien; Baker, Leonie; Hanton, Lyall; Robinson, Simon; Wormald, Peter J; Tan, Lorwai

2014-01-01

Chitosan-dextran gel has been used as an antihemostatic agent and antiadhesive agent after endoscopic sinus surgery. Because Staphylococcus aureus biofilms have been implicated in recalcitrant chronic rhinosinusitis, this study aimed to further investigate the (i) anti-inflammatory, (ii) bacterial biofilm inhibition, (iii) antiproliferative effects, and (iv) wound-healing properties of chitosan and chitosan-dextran gel. Fibroblasts were isolated from human nasal tissue and were used to determine the effects of chitosan and chitosan-dextran gel on (i) cell proliferation, (ii) wound healing, (iii) inflammation in fibroblast cultures challenged with superantigens S. aureus enterotoxin B (SEB) and toxic shock syndrome toxin (TSST), and (iv) on S. aureus biofilms. Chitosan was highly effective at reducing IL-8 expression after TSST and SEB challenge. Chitosan was also effective at reducing IL-8 expression of nonchallenged fibroblasts showing its anti-inflammatory effects on fibroblasts in a diseased state. Chitosan-dextran gel showed strong antibiofilm properties at 50% (v/v) concentration in vitro. Dextran, on its own, showed antibiofilm properties at 1.25% (w/v) concentration. Chitosan, on its own, reduced proliferation of fibroblasts to 82% of control proliferation and chitosan-dextran gel reduced proliferation of the fibroblasts to 0.04% of control proliferation. Relative to the no treatment controls, chitosan-dextran gel significantly delayed the wound-healing rate over the first 48 hours of the experiment. Chitosan-dextran gel reduced fibroblast proliferation and wound-healing time, showing a possible mechanism of reducing adhesions in the postsurgical period. Chitosan reduced IL-8 levels, showing its anti-inflammatory properties. Chitosan-dextran gel and dextran treatment showed antibiofilm properties in our model.

Surface modification of silicon wafer by grafting zwitterionic polymers to improve its antifouling property

NASA Astrophysics Data System (ADS)

Sun, Yunlong; Chen, Changlin; Xu, Heng; Lei, Kun; Xu, Guanzhe; Zhao, Li; Lang, Meidong

2017-10-01

Silicon (111) wafer was modified by triethoxyvinylsilane containing double bond as an intermedium, and then P4VP (polymer 4-vinyl pyridine) brush was "grafted" onto the surface of silicon wafer containing reactive double bonds by adopting the "grafting from" way and Si-P4VP substrate (silicon wafer grafted by P4VP) was obtained. Finally, P4VP brush of Si-P4VP substrate was modified by 1,3-propanesulfonate fully to obtain P4VP-psl brush (zwitterionic polypyridinium salt) and the functional Si-P4VP-psl substrate (silicon wafer grafted by zwitterionic polypyridinium salt based on polymer 4-vinyl pyridine) was obtained successfully. The antifouling property of the silicon wafer, the Si-P4VP substrate and the Si-P4VP-psl substrate was investigated by using bovine serum albumin, mononuclear macrophages (RAW 264.7) and Escherichia coli (E. coli) ATTC25922 as model bacterium. The results showed that compared with the blank sample-silicon wafer, the Si-P4VP-psl substrate had excellent anti-adhesion ability against bovine serum albumin, cells and bacterium, due to zwitterionic P4VP-psl brush (polymer 4-vinyl pyridine salt) having special functionality like antifouling ability on biomaterial field.

Non-pharmacological treatment of Helicobacter pylori

PubMed Central

Shmuely, Haim; Domniz, Noam; Yahav, Jacob

2016-01-01

Many food and plant extracts have shown in vitro anti-Helicobacter pylori (H. pylori) activity, but are less effective in vivo. The anti-H. pylori effects of these extracts are mainly permeabilitization of the membrane, anti-adhesion, inhibition of bacterial enzymes and bacterial grown. We, herein, review treatment effects of cranberry, garlic, curcumin, ginger and pistacia gum against H. pylori in both in vitro, animal studies and in vivo studies. PMID:27158532

Anti-Adhesion Activity of A2-type Proanthocyanidins (a Cranberry Major Component) on Uropathogenic E. coli and P. mirabilis Strains

PubMed Central

Nicolosi, Daria; Tempera, Gianna; Genovese, Carlo; Furneri, Pio M.

2014-01-01

Urinary tract infections (UTIs) are relatively common in women and may be classified as uncomplicated or complicated, depending upon the urinary tract anatomy and physiology. Acute uncomplicated cystitis (AUC) occurs when urinary pathogens from the bowel or vagina colonize the periurethral mucosa and reach the bladder. The vast majority of episodes in healthy women involving the same bacterial strain that caused the initial infection are thought to be reinfections. About 90% of AUC are caused by uropathogenic Escherichia coli (UPEC), but Proteus mirabilis also plays an important role. Several studies support the importance of cranberry (Vaccinium macrocarpon) proanthocyanidins in preventing adhesion of P-fimbriated UPEC to uroepithelial cells. In this study, we evaluated the in vitro anti-adhesion activity of A2-linked proanthocyanidins from cranberry on a UPEC and Proteus mirabilis strains and their possible influence on urease activity of the latter. A significant reduction of UPEC adhesion (up to 75%) on the HT1376 cell line was observed vs. control. For the strains of P. mirabilis there was also a reduction of adhesion (up to 75%) compared to controls, as well as a reduction in motility and urease activity. These results suggest that A2-type cranberry proanthocyanidins could aid in maintaining urinary tract health. PMID:27025740

Patterning N-type and S-type neuroblastoma cells with Pluronic F108 and ECM proteins.

PubMed

Corey, Joseph M; Gertz, Caitlyn C; Sutton, Thomas J; Chen, Qiaoran; Mycek, Katherine B; Wang, Bor-Shuen; Martin, Abbey A; Johnson, Sara L; Feldman, Eva L

2010-05-01

Influencing cell shape using micropatterned substrates affects cell behaviors, such as proliferation and apoptosis. Cell shape may also affect these behaviors in human neuroblastoma (NBL) cancer, but to date, no substrate design has effectively patterned multiple clinically important human NBL lines. In this study, we investigated whether Pluronic F108 was an effective antiadhesive coating for human NBL cells and whether it would localize three NBL lines to adhesive regions of tissue culture plastic or collagen I on substrate patterns. The adhesion and patterning of an S-type line, SH-EP, and two N-type lines, SH-SY5Y and IMR-32, were tested. In adhesion assays, F108 deterred NBL adhesion equally as well as two antiadhesive organofunctional silanes and far better than bovine serum albumin. Patterned stripes of F108 restricted all three human NBL lines to adhesive stripes of tissue culture plastic. We then investigated four schemes of applying collagen and F108 to different regions of a substrate. Contact with collagen obliterates the ability of F108 to deter NBL adhesion, limiting how both materials can be applied to substrates to produce high fidelity NBL patterning. This patterned substrate design should facilitate investigations of the role of cell shape in NBL cell behavior. Copyright 2009 Wiley Periodicals, Inc.

Patterning N-type and S-type Neuroblastoma Cells with Pluronic F108 and ECM Proteins

PubMed Central

Corey, Joseph M.; Gertz, Caitlyn C.; Sutton, Thomas J.; Chen, Qiaoran; Mycek, Katherine B.; Wang, Bor-Shuen; Martin, Abbey A.; Johnson, Sara L.; Feldman, Eva L.

2009-01-01

Influencing cell shape using micropatterned substrates affects cell behaviors, such as proliferation and apoptosis. Cell shape may also affect these behaviors in human neuroblastoma (NBL) cancer, but to date, no substrate design has effectively patterned multiple clinically important human NBL lines. In this study, we investigated whether Pluronic F108 was an effective anti-adhesive coating for human NBL cells and whether it would localize three NBL lines to adhesive regions of tissue culture plastic or collagen I on substrate patterns. The adhesion and patterning of an S-type line, SH-EP, and two N-type lines, SH-SY5Y and IMR-32, were tested. In adhesion assays, F108 deterred NBL adhesion equally as well as two anti-adhesive organofunctional silanes and far better than bovine serum albumin. Patterned stripes of F108 restricted all three human NBL lines to adhesive stripes of tissue culture plastic. We then investigated four schemes of applying collagen and F108 to different regions of a substrate. Contact with collagen obliterates the ability of F108 to deter NBL adhesion, limiting how both materials can be applied to substrates to produce high fidelity NBL patterning. This patterned substrate design should facilitate investigations of the role of cell shape in NBL cell behavior. PMID:19609877

Sickle red cell adhesion: many issues and some answers.

PubMed

Kaul, D K

2008-01-01

Among multiple pathologies associated with sickle cell disease, sickle red cell-endothelial interaction has been implicated as a potential initiating mechanism in vaso-occlusive events that characterize this disease. Vast literature exists on various aspects of sickle red cell adhesion, but many issues remain unresolved, especially pertaining to the role of sickle red cell heterogeneity, the relative role of multiple adhesion mechanisms and targets of antiadhesive therapy. This review briefly analyzes these issues.

Role of surface layer collagen binding protein from indigenous Lactobacillus plantarum 91 in adhesion and its anti-adhesion potential against gut pathogen.

PubMed

Yadav, Ashok Kumar; Tyagi, Ashish; Kaushik, Jai Kumar; Saklani, Asha Chandola; Grover, Sunita; Batish, Virender Kumar

2013-12-14

Human feacal isolates were ascertain as genus Lactobacillus using specific primer LbLMA1/R16-1 and further identified as Lactobacillus plantarum with species specific primers Lpl-3/Lpl-2. 25 L. plantarum strains were further assessed for hydrophobicity following the microbial adhesion to hydrocarbons (MATH) method and colonization potentials based on their adherence to immobilized human collagen type-1. Surface proteins were isolated from selected L. plantarum 91(Lp91) strain. The purified collagen binding protein (Cbp) protein was assessed for its anti-adhesion activity against enteric Escherichia coli 0157:H7 pathogen on immobilized collagen. Four L. plantarum strains displayed high degree of hydrophobicity and significant adhesion to collagen. A 72 kDa protein was purified which reduced 59.71% adhesion of E. coli 0157:H7 on immobilized collagen as compared to control well during adhesion assay. Cbp protein is the major influencing factor in inhibition of E. coli 0157:H7 adhesion with extracellular matrix (ECM) components. Hydrophobicity and adhesion potential are closely linked attributes precipitating in better colonization potential of the lactobacillus strains. Cbp is substantiated as a crucial surface protein contributing in adhesion of lactobacillus strains. The study can very well be the platform for commercialization of indigenous probiotic strain once their functional attributes are clinically explored. Copyright © 2013 Elsevier GmbH. All rights reserved.

In vitro characterization of multivalent adhesion molecule 7-based inhibition of multidrug-resistant bacteria isolated from wounded military personnel.

PubMed

Krachler, Anne Marie; Mende, Katrin; Murray, Clinton; Orth, Kim

2012-07-01

Treatment of wounded military personnel at military medical centers is often complicated by colonization and infection of wounds with pathogenic bacteria. These include nosocomially transmitted, often multidrug-resistant pathogens such as Acinetobacter baumannii-calcoaceticus complex, Pseudomonas aeruginosa and extended spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae. We analyzed the efficacy of multivalent adhesion molecule (MAM) 7-based anti-adhesion treatment of host cells against aforementioned pathogens in a tissue culture infection model. Herein, we observed that a correlation between two important hallmarks of virulence, attachment and cytotoxicity, could serve as a useful predictor for the success of MAM7-based inhibition against bacterial infections. Initially, we characterized 20 patient isolates (five from each pathogen mentioned above) in terms of genotypic diversity, antimicrobial susceptibility and important hallmarks of pathogenicity (biofilm formation, attachment to and cytotoxicity toward cultured host cells). All isolates displayed a high degree of genotypic diversity, which was also reflected by large strain-to-strain variability in terms of biofilm formation, attachment and cytotoxicity within each group of pathogen. Using non-pathogenic bacteria expressing MAM7 or latex beads coated with recombinant MAM7 for anti-adhesion treatment, we showed a decrease in cytotoxicity, indicating that MAM7 has potential as a prophylactic agent to attenuate infection by multidrug-resistant bacterial pathogens.

In vitro characterization of multivalent adhesion molecule 7-based inhibition of multidrug-resistant bacteria isolated from wounded military personnel

PubMed Central

Krachler, Anne Marie; Mende, Katrin; Murray, Clinton; Orth, Kim

2012-01-01

Treatment of wounded military personnel at military medical centers is often complicated by colonization and infection of wounds with pathogenic bacteria. These include nosocomially transmitted, often multidrug-resistant pathogens such as Acinetobacter baumannii-calcoaceticus complex, Pseudomonas aeruginosa and extended spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae. We analyzed the efficacy of multivalent adhesion molecule (MAM) 7-based anti-adhesion treatment of host cells against aforementioned pathogens in a tissue culture infection model. Herein, we observed that a correlation between two important hallmarks of virulence, attachment and cytotoxicity, could serve as a useful predictor for the success of MAM7-based inhibition against bacterial infections. Initially, we characterized 20 patient isolates (five from each pathogen mentioned above) in terms of genotypic diversity, antimicrobial susceptibility and important hallmarks of pathogenicity (biofilm formation, attachment to and cytotoxicity toward cultured host cells). All isolates displayed a high degree of genotypic diversity, which was also reflected by large strain-to-strain variability in terms of biofilm formation, attachment and cytotoxicity within each group of pathogen. Using non-pathogenic bacteria expressing MAM7 or latex beads coated with recombinant MAM7 for anti-adhesion treatment, we showed a decrease in cytotoxicity, indicating that MAM7 has potential as a prophylactic agent to attenuate infection by multidrug-resistant bacterial pathogens. PMID:22722243

Polyphenol, antioxidant and antimicrobial potential of six different white and red wine grape processing leftovers.

PubMed

Trošt, Kajetan; Klančnik, Anja; Mozetič Vodopivec, Branka; Sternad Lemut, Melita; Jug Novšak, Katja; Raspor, Peter; Smole Možina, Sonja

2016-11-01

During winemaking, grape polyphenols are only partly extracted, and consequently unexploited. The main aim was to characterize the phenolic content of freeze-dried grape skin and seed (FDSS) extracts obtained from Slovenian and international grape varieties and to evaluate their antioxidant, antimicrobial and anti-adhesive activities. FDSS of six Vitis vinifera L. grapevine cultivars from Vipava Valley region (Slovenia) underwent extraction and sonification under different conditions. Flavonols were the predominant content of extracts from white 'Zelen' and 'Sauvignon Blanc' grape varieties, with strong antimicrobial activities against Gram-negative bacteria. 'Pinot Noir' FDSS extracted with 50% aqueous ethanol extraction produced a high phenolic content in the final extract, which was further associated with strong antioxidant and antimicrobial activities against all tested bacteria. Bacterial adhesion to stainless steel surfaces with minimal and maximal surface roughness was significantly inhibited (up to 60%) across a wide FDSS concentration range, with lower concentrations also effective with two types of stainless steel surfaces. FDSS extracts from winery by-products show interesting phenolic profiles that include flavonols, catechins, anthocyanins and hydroxycinnamic acids, with yields influenced by grapevine cultivar and extraction conditions. The antioxidant, antimicrobial and anti-adhesive activities of 50% aqueous ethanol 'Pinot Noir' FDSS extract reveals potential applications in food, pharmaceutical and cosmetic industries for these bioactive residues. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Antibacterial and Antiadhesive Activities of Extracts from Edible Plants against Soft Drink Spoilage by Asaia spp.

PubMed

Antolak, Hubert; Czyzowska, Agata; Kregiel, Dorota

2017-01-01

This study was conducted to investigate the antibacterial and antiadhesive activities of ethanol extracts from five edible plant parts: cinnamon bark ( Cinnamomum zeylanicum ), licorice root ( Glycyrrhiza radix ), nettle leaves ( Urtica dioica ), green tea leaves ( Camellia sinensis ), and elderberry flowers ( Sambucus nigra ). The chemical constituents of the extracts were identified using high-performance liquid chromatography and liquid chromatography plus mass spectrometry. Six strains of Asaia lannensis and Asaia bogorensis bacteria isolated from spoiled commercial fruit-flavored noncarbonated mineral water were used. Bacterial adhesion to polystyrene as an attachment substrate in culture media supplemented with 10% plant extract was evaluated using luminometric measurement of the ATP extracted from adhered cells. The viability of the adhered and planktonic cells was assessed using the plate count method, and the relative adhesion coefficient was calculated. All tested crude extracts contained flavonols (kaempferol, quercetin, and their derivatives), flavanols (catechin and derivatives), flavanones (glabrol, licorice glycoside A, and liquiritin), and phenolic acids (gallic, quinic, chlorogenic, neochlorogenic, caffeic, coumaric, and ferulic). The culture medium with 10% elderberry extract provided the least favorable environment for all tested bacterial strains. Extracts from green tea, cinnamon, and licorice also had significant inhibitory effects on the adhesion of the tested bacterial strains. This research suggests that the addition of selected edible plant extracts could improve the microbial stability of noncarbonated soft drinks.

Structure and mechanical behaviors of protective armored pangolin scales and effects of hydration and orientation.

PubMed

Liu, Z Q; Jiao, D; Weng, Z Y; Zhang, Z F

2016-03-01

As natural flexible dermal armor, pangolin scales provide effective protection against predatory threats and possess other notable properties such as anti-adhesion and wear-resistance. In this study, the structure, mechanical properties, deformation and damage behaviors of pangolin scales were systematically investigated with the effects of hydration and orientation evaluated. The scales are divided into three macro-layers constituted by overlapping keratin tiles with distinct lamellar arrangements which are further composed of lower-ordered lamellae. Both hardness and strength are significantly decreased by hydration; while the plasticity is markedly improved concomitantly, and as such, the mechanical damages are mitigated. The tensile strength invariably approximates to one third of hardness in value. The tensile deformation is dominated by lamellae stretching and pulling out under wet condition, which is distinct from the trans-lamellar fracture in dry samples. The compressive behaviors are featured by pronounced plasticity in both dry and wet scales; and notable strain-hardening capacity is introduced by hydration, especially along the thickness direction wherein kinking occurs. Inter-lamellar cracking is effectively alleviated in wet samples compared with the dry ones and both of them deform by macroscopic buckling. This study may help stimulate possible inspiration for the design of high-performance synthetic armor materials by mimicking pangolin scales. Copyright © 2015 Elsevier Ltd. All rights reserved.

Adhesions and endometriosis: challenges in subfertility management : (An expert opinion of the ANGEL-The ANti-Adhesions in Gynaecology Expert PaneL-group).

PubMed

De Wilde, R L; Alvarez, J; Brölmann, H; Campo, R; Cheong, Y; Lundorff, P; Pawelczyk, L; Roman, H; di Spiezio Sardo, A; Wallwiener, M

2016-08-01

There is molecular evidence that endometriosis has a negative impact on the ovaries, although the exact pathophysiology concerning endometriosis-associated subfertility is not known. The negative impact on the tubo-ovarian unit can be directly by distorting the anatomy, indirectly by invoking inflammation or by oxidative damage with poorer-quality oocytes. Endometriosis even seems to have a negative effect on pregnancy outcome after in vitro fertilization.

[Cranberry (Vaccinium macrocarpon) and urinary tract infections: study model and review of literature].

PubMed

Lavigne, J-P; Bourg, G; Botto, H; Sotto, A

2007-11-01

Cranberries (Vaccinium macrocarpon) have long been the focus of interest for their beneficial effects in preventing urinary tract infections. Among cranberry compounds, a group of proanthocyanidins (PACs) with A-type linkages were isolated which exhibit bacterial anti-adhesion activity against uropathogenic Escherichia coli strains. These PAC inhibit P-fimbriae synthesis and induce a bacterial deformation. This activity was demonstrated on both antibiotic susceptible and resistant bacteria. This review focused on the last discoveries in the knowledge of cranberry effects.

Prospects for the therapeutic application of sulfated polysaccharides of brown algae in diseases of the cardiovascular system: review.

PubMed

Zaporozhets, Tatyana; Besednova, Natalia

2016-12-01

Fucoidans are water-soluble, highly sulfated, branched homo- and hetero-polysaccharides derived from the fibrillar cell walls and intercellular spaces of brown seaweeds of the class Phaeophyceae. Fucoidans possess mimetic properties of the natural ligands of protein receptors and regulate functions of biological systems via key signaling molecules. The aim of this review was to collect and combine all available scientific literature about the potential use of the fucoidans for diseases of cardiovascular system. The review has been compiled using references from major databases such as Web of Science, PubMed, Scopus, Elsevier, Springer and Google Scholar (up to September 2015). After obtaining all reports from database (a total number is about 580), the papers were carefully analyzed in order to find data related to the topic of this review (129 references). An exhaustive survey of literature revealed that fucoidans possess a broad spectrum of biological activity, including anti-coagulant, hypolipidemic, anti-thrombotic, anti-inflammatory, immunomodulatory, anti-tumor, anti-adhesive and anti-hypertensive properties. Numerous investigations of fucoidans in diseases of the cardiovascular system mainly focus on pleiotropic anti-inflammatory effects. Fucoidans also possess pro-angiogenic and pro-vasculogenic properties. A great number of investigations in the past years have demonstrated that fucoidans has great potential for in-depth investigation of their effects on cardiovascular system. Through this review, the authors hope to attract the attention of researchers to use fucoidan as mimetic of natural ligand receptor protein with the view of developing new formulations with an improved therapeutic value.

Utilization of star-shaped polymer architecture in the creation of high-density polymer brush coatings for the prevention of platelet and bacteria adhesion

PubMed Central

Totani, Masayasu; Terada, Kayo; Terashima, Takaya; Kim, Ill Yong; Ohtsuki, Chikara; Xi, Chuanwu; Tanihara, Masao

2014-01-01

We demonstrate utilization of star-shaped polymers as high-density polymer brush coatings and their effectiveness to inhibit the adhesion of platelets and bacteria. Star polymers consisting of poly(2-hydroxyethyl methacrylate) (PHEMA) and/or poly(methyl methacrylate) (PMMA), were synthesized using living radical polymerization with a ruthenium catalyst. The polymer coatings were prepared by simple drop casting of the polymer solution onto poly(ethylene terephthalate) (PET) surfaces and then dried. Among the star polymers prepared in this study, the PHEMA star polymer (star-PHEMA) and the PHEMA/PMMA (mol. ratio of 71/29) heteroarm star polymer (star-H71M29) coatings showed the highest percentage of inhibition against platelet adhesion (78–88% relative to noncoated PET surface) and Escherichia coli (94–97%). These coatings also showed anti-adhesion activity against platelets after incubation in Dulbecco's phosphate buffered saline or surfactant solution for 7 days. In addition, the PMMA component of the star polymers increased the scratch resistance of the coating. These results indicate that the star-polymer architecture provides high polymer chain density on PET surfaces to prevent adhesion of platelets and bacteria, as well as coating stability and physical durability to prevent exposure of bare PET surfaces. The star polymers provide a simple and effective approach to preparing anti-adhesion polymer coatings on biomedical materials against the adhesion of platelets and bacteria. PMID:25485105

The Conformational Variability of FimH: Which Conformation Represents the Therapeutic Target?

PubMed

Eris, Deniz; Preston, Roland C; Scharenberg, Meike; Hulliger, Fabian; Abgottspon, Daniela; Pang, Lijuan; Jiang, Xiaohua; Schwardt, Oliver; Ernst, Beat

2016-06-02

FimH is a bacterial lectin found at the tips of type 1 pili of uropathogenic Escherichia coli (UPEC). It mediates shear-enhanced adhesion to mannosylated surfaces. Binding of UPEC to urothelial cells initiates the infection cycle leading to urinary tract infections (UTIs). Antiadhesive glycomimetics based on α-d-mannopyranose offer an attractive alternative to the conventional antibiotic treatment because they do not induce a selection pressure and are therefore expected to have a reduced resistance potential. Genetic variation of the fimH gene in clinically isolated UPEC has been associated with distinct mannose binding phenotypes. For this reason, we investigated the mannose binding characteristics of four FimH variants with mannose-based ligands under static and hydrodynamic conditions. The selected FimH variants showed individually different binding behavior under both sets of conditions as a result of the conformational variability of FimH. Clinically relevant FimH variants typically exist in a dynamic conformational equilibrium. Additionally, we evaluated inhibitory potencies of four FimH antagonists representing different structural classes. Inhibitory potencies of three of the tested antagonists were dependent on the binding phenotype and hence on the conformational equilibrium of the FimH variant. However, the squarate derivative was the notable exception and inhibited FimH variants irrespective of their binding phenotype. Information on antagonist affinities towards various FimH variants has remained largely unconsidered despite being essential for successful antiadhesion therapy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The effect of Piper betle and Psidium guajava extracts on the cell-surface hydrophobicity of selected early settlers of dental plaque.

PubMed

Razak, Fathilah Abdul; Othman, Rofina Yasmin; Rahim, Zubaidah Haji Abd

2006-06-01

The adhesion of early settlers of dental plaque to the tooth surface has a role in the initiation of the development of dental plaque. The hydrophobic surface properties of the bacteria cell wall are indirectly responsible for the adhesion of the bacteria cell to the acquired pellicle on the tooth surfaces. In this study, the effect of aqueous extract of two plants (Psidium guajava and Piper betle) on the cell-surface hydro-phobicity of early settlers of dental plaque was determined in vitro. Hexadecane, a hydrocarbon was used to represent the hydrophobic surface of the teeth in the oral cavity. It was found that treatment of the early plaque settlers with 1 mg/ml extract of Psidium guajava reduced the cell-surface hydrophobicity of Strep. sanguinis, Strep. mitis and Actinomyces sp. by 54.1%, 49.9% and 40.6%, respectively. Treatment of these bacteria with the same concentration of Piper betle however, showed a comparatively lesser effect (< 10%). It was also observed that the anti-adhesive effect of the two extracts on the binding of the early plaque settlers to hexadecane is concentration dependent.

Initial Bacterial Adhesion on Different Yttria-Stabilized Tetragonal Zirconia Implant Surfaces in Vitro

PubMed Central

Karygianni, Lamprini; Jähnig, Andrea; Schienle, Stefanie; Bernsmann, Falk; Adolfsson, Erik; Kohal, Ralf J.; Chevalier, Jérôme; Hellwig, Elmar; Al-Ahmad, Ali

2013-01-01

Bacterial adhesion to implant biomaterials constitutes a virulence factor leading to biofilm formation, infection and treatment failure. The aim of this study was to examine the initial bacterial adhesion on different implant materials in vitro. Four implant biomaterials were incubated with Enterococcus faecalis, Staphylococcus aureus and Candida albicans for 2 h: 3 mol % yttria-stabilized tetragonal zirconia polycrystal surface (B1a), B1a with zirconium oxide (ZrO2) coating (B2a), B1a with zirconia-based composite coating (B1b) and B1a with zirconia-based composite and ZrO2 coatings (B2b). Bovine enamel slabs (BES) served as control. The adherent microorganisms were quantified and visualized using scanning electron microscopy (SEM); DAPI and live/dead staining. The lowest bacterial count of E. faecalis was detected on BES and the highest on B1a. The fewest vital C. albicans strains (42.22%) were detected on B2a surfaces, while most E. faecalis and S. aureus strains (approximately 80%) were vital overall. Compared to BES; coated and uncoated zirconia substrata exhibited no anti-adhesive properties. Further improvement of the material surface characteristics is essential. PMID:28788415

Initial Bacterial Adhesion on Different Yttria-Stabilized Tetragonal Zirconia Implant Surfaces in Vitro.

PubMed

Karygianni, Lamprini; Jähnig, Andrea; Schienle, Stefanie; Bernsmann, Falk; Adolfsson, Erik; Kohal, Ralf J; Chevalier, Jérôme; Hellwig, Elmar; Al-Ahmad, Ali

2013-12-04

Bacterial adhesion to implant biomaterials constitutes a virulence factor leading to biofilm formation, infection and treatment failure. The aim of this study was to examine the initial bacterial adhesion on different implant materials in vitro . Four implant biomaterials were incubated with Enterococcus faecalis , Staphylococcus aureus and Candida albicans for 2 h: 3 mol % yttria-stabilized tetragonal zirconia polycrystal surface (B1a), B1a with zirconium oxide (ZrO₂) coating (B2a), B1a with zirconia-based composite coating (B1b) and B1a with zirconia-based composite and ZrO₂ coatings (B2b). Bovine enamel slabs (BES) served as control. The adherent microorganisms were quantified and visualized using scanning electron microscopy (SEM); DAPI and live/dead staining. The lowest bacterial count of E. faecalis was detected on BES and the highest on B1a. The fewest vital C. albicans strains (42.22%) were detected on B2a surfaces, while most E. faecalis and S. aureus strains (approximately 80%) were vital overall. Compared to BES; coated and uncoated zirconia substrata exhibited no anti-adhesive properties. Further improvement of the material surface characteristics is essential.

Will parents participate in and comply with programs and regimens using xylitol for preventing acute otitis media in their children?

PubMed

Danhauer, Jeffrey L; Johnson, Carole E; Baker, Jason A; Ryu, Jung A; Smith, Rachel A; Umeda, Claire J

2015-04-01

Antiadhesive properties in xylitol, a natural sugar alcohol, can help prevent acute otitis media (AOM) in children by inhibiting harmful bacteria from colonizing and adhering to oral and nasopharyngeal areas and traveling to the Eustachian tube and middle ear. This study investigated parents' willingness to use and comply with a regimen of xylitol for preventing AOM in their preschool- and kindergarten-aged children. An Internet questionnaire was designed and administered to parents of young children in preschool and kindergarten settings. Most parents were unaware of xylitol's use for AOM and would not likely comply with regimens for preventing AOM in their children; however, parents having previous knowledge of xylitol and whose children had a history of AOM would be more likely to do so. Generally, most of these parents did not know about xylitol and probably would not use it to prevent ear infections. Unfortunately, these results parallel earlier findings for teachers and schools, which present obstacles for establishing ear infection prevention programs using similar protocols for young children. The results showed that considerable education and age-appropriate vehicles for administering xylitol are needed before establishing AOM prevention programs in schools and/or at home.

Brochosomal coats turn leafhopper (Insecta, Hemiptera, Cicadellidae) integument to superhydrophobic state

PubMed Central

Rakitov, Roman; Gorb, Stanislav N.

2013-01-01

Leafhoppers (Insecta, Hemiptera, Cicadellidae) actively coat their integuments with brochosomes, hollow proteinaceous spheres of usually 200–700 nm in diameter, with honeycombed walls. The coats have been previously suggested to act as a water-repellent and anti-adhesive protective barrier against the insect's own exudates. We estimated their wettability through contact angle (CA) measurements of water, diiodomethane, ethylene glycol and ethanol on detached wings of the leafhoppers Alnetoidia alneti, Athysanus argentarius and Cicadella viridis. Intact brochosome-coated integuments were repellent to all test liquids, except ethanol, and exhibited superhydrophobicity, with the average water CAs of 165–172°, and the apparent surface free energy (SFE) estimates not exceeding 0.74 mN m−1. By contrast, the integuments from which brochosomes were removed with a peeling technique using fluid polyvinylsiloxane displayed water CAs of only 103–129° and SFEs above 20 mN m−1. Observations of water-sprayed wings in a cryo-scanning electron microscope confirmed that brochosomal coats prevented water from contacting the integument. Their superhydrophobic properties appear to result from fractal roughness, which dramatically reduces the area of contact with high-surface-tension liquids, including, presumably, leafhopper exudates. PMID:23235705

Endogenous adenosine produced during hypoxia attenuates neutrophil accumulation: coordination by extracellular nucleotide metabolism.

PubMed

Eltzschig, Holger K; Thompson, Linda F; Karhausen, Jorn; Cotta, Richard J; Ibla, Juan C; Robson, Simon C; Colgan, Sean P

2004-12-15

Hypoxia is a well-documented inflammatory stimulus and results in tissue polymorphonuclear leukocyte (PMN) accumulation. Likewise, increased tissue adenosine levels are commonly associated with hypoxia, and given the anti-inflammatory properties of adenosine, we hypothesized that adenosine production via adenine nucleotide metabolism at the vascular surface triggers an endogenous anti-inflammatory response during hypoxia. Initial in vitro studies indicated that endogenously generated adenosine, through activation of PMN adenosine A(2A) and A(2B) receptors, functions as an antiadhesive signal for PMN binding to microvascular endothelia. Intravascular nucleotides released by inflammatory cells undergo phosphohydrolysis via hypoxia-induced CD39 ectoapyrase (CD39 converts adenosine triphosphate/adenosine diphosphate [ATP/ADP] to adenosine monophosphate [AMP]) and CD73 ecto-5'-nucleotidase (CD73 converts AMP to adenosine). Extensions of our in vitro findings using cd39- and cd73-null animals revealed that extracellular adenosine produced through adenine nucleotide metabolism during hypoxia is a potent anti-inflammatory signal for PMNs in vivo. These findings identify CD39 and CD73 as critical control points for endogenous adenosine generation and implicate this pathway as an innate mechanism to attenuate excessive tissue PMN accumulation.

Nanoscale biophysical properties of the cell surface galactosaminogalactan from the fungal pathogen Aspergillus fumigatus

NASA Astrophysics Data System (ADS)

Beaussart, Audrey; El-Kirat-Chatel, Sofiane; Fontaine, Thierry; Latgé, Jean-Paul; Dufrêne, Yves F.

2015-09-01

Many fungal pathogens produce cell surface polysaccharides that play essential roles in host-pathogen interactions. In Aspergillus fumigatus, the newly discovered polysaccharide galactosaminogalactan (GAG) mediates adherence to a variety of substrates through molecular mechanisms that are poorly understood. Here we use atomic force microscopy to unravel the localization and adhesion of GAG on living fungal cells. Using single-molecule imaging with tips bearing anti-GAG antibodies, we found that GAG is massively exposed on wild-type (WT) germ tubes, consistent with the notion that this glycopolymer is secreted by the mycelium of A. fumigatus, while it is lacking on WT resting conidia and on germ tubes from a mutant (Δuge3) deficient in GAG. Imaging germ tubes with tips bearing anti-β-glucan antibodies shows that exposure of β-glucan is strongly increased in the Δuge3 mutant, indicating that this polysaccharide is masked by GAG during hyphal growth. Single-cell force measurements show that expression of GAG on germ tubes promotes specific adhesion to pneumocytes and non-specific adhesion to hydrophobic substrates. These results provide a molecular foundation for the multifunctional adhesion properties of GAG, thus suggesting it could be used as a potential target in anti-adhesion therapy and immunotherapy. Our methodology represents a powerful approach for characterizing the nanoscale organization and adhesion of cell wall polysaccharides during fungal morphogenesis, thereby contributing to increase our understanding of their role in biofilm formation and immune responses.

Inhibition of blood platelet adhesion by phenolics' rich fraction of Hippophae rhamnoides L. fruits.

PubMed

Olas, B; Kontek, B; Szczesna, M; Grabarczyk, L; Stochmal, A; Zuchowski, J

2017-04-01

Beneficial influence of fruits on human health may be their ability to prevent the hyperactivation of blood platelets and cardiovascular disorders. Effects of the phenolic fraction from Hippophae rhamnoides fruit on different stages of blood platelet activation (platelet adhesion and aggregation) were studied in vitro. We also examined effects of the H. rhamnoides fraction on metabolism of thiol groups, which plays an important role in platelet functions. The effects of the H. rhamnoides fraction on adhesion of blood platelets to collagen and fibrinogen were determined with Tuszynski's and Murphy's method. The platelet aggregation was determined with turbidimetry. The action of the H. rhamnoides fraction on the level of thiol groups in platelet proteins and a level of glutathione (GSH) in platelets was estimated with 5,5'-dithio-bis(2-nitro-benzoic acid). The tested fraction of H. rhamnoides (0.5 - 50 μg/ml; 30 min of the incubation time 30 min) inhibited blood platelets adhesion to collagen and fibrinogen. The effect of the tested fraction on blood platelet adhesion depended on concentration of fraction. In presence of the highest tested concentration which was 50 μg/ml, inhibition of platelet adhesion for thrombin-activated platelets was about 55%. On the other hand, tested plant fraction had no anti-aggregatory properties. Our results showed anti-adhesive properties of phenolic fraction from H. rhamnoides fruit and we suggest that it may be beneficial for prevention of cardiovascular diseases.

Inhibition of type 1 fimbriae-mediated Escherichia coli adhesion and biofilm formation by trimeric cluster thiomannosides conjugated to diamond nanoparticles

NASA Astrophysics Data System (ADS)

Khanal, Manakamana; Larsonneur, Fanny; Raks, Victoriia; Barras, Alexandre; Baumann, Jean-Sébastien; Martin, Fernando Ariel; Boukherroub, Rabah; Ghigo, Jean-Marc; Ortiz Mellet, Carmen; Zaitsev, Vladimir; Garcia Fernandez, Jose M.; Beloin, Christophe; Siriwardena, Aloysius; Szunerits, Sabine

2015-01-01

Recent advances in nanotechnology have seen the development of a number of microbiocidal and/or anti-adhesive nanoparticles displaying activity against biofilms. In this work, trimeric thiomannoside clusters conjugated to nanodiamond particles (ND) were targeted for investigation. NDs have attracted attention as a biocompatible nanomaterial and we were curious to see whether the high mannose glycotope density obtained upon grouping monosaccharide units in triads might lead to the corresponding ND-conjugates behaving as effective inhibitors of E. coli type 1 fimbriae-mediated adhesion as well as of biofilm formation. The required trimeric thiosugar clusters were obtained through a convenient thiol-ene ``click'' strategy and were subsequently conjugated to alkynyl-functionalized NDs using a Cu(i)-catalysed ``click'' reaction. We demonstrated that the tri-thiomannoside cluster-conjugated NDs (ND-Man3) show potent inhibition of type 1 fimbriae-mediated E. coli adhesion to yeast and T24 bladder cells as well as of biofilm formation. The biofilm disrupting effects demonstrated here have only rarely been reported in the past for analogues featuring such simple glycosidic motifs. Moreover, the finding that the tri-thiomannoside cluster (Man3N3) is itself a relatively efficient inhibitor, even when not conjugated to any ND edifice, suggests that alternative mono- or multivalent sugar-derived analogues might also be usefully explored for E. coli-mediated biofilm disrupting properties.Recent advances in nanotechnology have seen the development of a number of microbiocidal and/or anti-adhesive nanoparticles displaying activity against biofilms. In this work, trimeric thiomannoside clusters conjugated to nanodiamond particles (ND) were targeted for investigation. NDs have attracted attention as a biocompatible nanomaterial and we were curious to see whether the high mannose glycotope density obtained upon grouping monosaccharide units in triads might lead to the corresponding ND-conjugates behaving as effective inhibitors of E. coli type 1 fimbriae-mediated adhesion as well as of biofilm formation. The required trimeric thiosugar clusters were obtained through a convenient thiol-ene ``click'' strategy and were subsequently conjugated to alkynyl-functionalized NDs using a Cu(i)-catalysed ``click'' reaction. We demonstrated that the tri-thiomannoside cluster-conjugated NDs (ND-Man3) show potent inhibition of type 1 fimbriae-mediated E. coli adhesion to yeast and T24 bladder cells as well as of biofilm formation. The biofilm disrupting effects demonstrated here have only rarely been reported in the past for analogues featuring such simple glycosidic motifs. Moreover, the finding that the tri-thiomannoside cluster (Man3N3) is itself a relatively efficient inhibitor, even when not conjugated to any ND edifice, suggests that alternative mono- or multivalent sugar-derived analogues might also be usefully explored for E. coli-mediated biofilm disrupting properties. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr05906a

Zwitterionic sulfobetaine polymer-immobilized surface by simple tyrosinase-mediated grafting for enhanced antifouling property.

PubMed

Kwon, Ho Joon; Lee, Yunki; Phuong, Le Thi; Seon, Gyeung Mi; Kim, Eunsuk; Park, Jong Chul; Yoon, Hyunjin; Park, Ki Dong

2017-10-01

Introducing antifouling property to biomaterial surfaces has been considered an effective method for preventing the failure of implanted devices. In order to achieve this, the immobilization of zwitterions on biomaterial surfaces has been proven to be an excellent way of improving anti-adhesive potency. In this study, poly(sulfobetaine-co-tyramine), a tyramine-conjugated sulfobetaine polymer, was synthesized and simply grafted onto the surface of polyurethane via a tyrosinase-mediated reaction. Surface characterization by water contact angle measurements, X-ray photoelectron spectroscopy and atomic force microscopy demonstrated that the zwitterionic polymer was successfully introduced onto the surface of polyurethane and remained stable for 7days. In vitro studies revealed that poly(sulfobetaine-co-tyramine)-coated surfaces dramatically reduced the adhesion of fibrinogen, platelets, fibroblasts, and S. aureus by over 90% in comparison with bare surfaces. These results proved that polyurethane surfaces grafted with poly(sulfobetaine-co-tyramine) via a tyrosinase-catalyzed reaction could be promising candidates for an implantable medical device with excellent bioinert abilities. Antifouling surface modification is one of the key strategy to prevent the thrombus formation or infection which occurs on the surface of biomaterial after transplantation. Although there are many methods to modify the surface have been reported, necessity of simple modification technique still exists to apply for practical applications. The purpose of this study is to modify the biomaterial's surface by simply immobilizing antifouling zwitterion polymer via enzyme tyrosinase-mediated reaction which could modify versatile substrates in mild aqueous condition within fast time period. After modification, pSBTA grafted surface becomes resistant to various biological factors including proteins, cells, and bacterias. This approach appears to be a promising method to impart antifouling property on biomaterial surfaces. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Preclinical studies in support of defibrotide for the treatment of multiple myeloma and other neoplasias.

PubMed

Mitsiades, Constantine S; Rouleau, Cecile; Echart, Cinara; Menon, Krishna; Teicher, Beverly; Distaso, Maria; Palumbo, Antonio; Boccadoro, Mario; Anderson, Kenneth C; Iacobelli, Massimo; Richardson, Paul G

2009-02-15

Defibrotide, an orally bioavailable polydisperse oligonucleotide, has promising activity in hepatic veno-occlusive disease, a stem cell transplantation-related toxicity characterized by microangiopathy. The antithrombotic properties of defibrotide and its minimal hemorrhagic risk could serve for treatment of cancer-associated thrombotic complications. Given its cytoprotective effect on endothelium, we investigated whether defibrotide protects tumor cells from cytotoxic antitumor agents. Further, given its antiadhesive properties, we evaluated whether defibrotide modulates the protection conferred to multiple myeloma cells by bone marrow stromal cells. Defibrotide lacks significant single-agent in vitro cytotoxicity on multiple myeloma or solid tumor cells and does not attenuate their in vitro response to dexamethasone, bortezomib, immunomodulatory thalidomide derivatives, and conventional chemotherapeutics, including melphalan and cyclophosphamide. Importantly, defibrotide enhances in vivo chemosensitivity of multiple myeloma and mammary carcinoma xenografts in animal models. In cocultures of multiple myeloma cells with bone marrow stromal cells in vitro, defibrotide enhances the multiple myeloma cell sensitivity to melphalan and dexamethasone, and decreases multiple myeloma-bone marrow stromal cell adhesion and its sequelae, including nuclear factor-kappaB activation in multiple myeloma and bone marrow stromal cells, and associated cytokine production. Moreover, defibrotide inhibits expression and/or function of key mediators of multiple myeloma interaction with bone marrow stromal cell and endothelium, including heparanase, angiogenic cytokines, and adhesion molecules. Defibrotide's in vivo chemosensitizing properties and lack of direct in vitro activity against tumor cells suggest that it favorably modulates antitumor interactions between bone marrow stromal cells and endothelia in the tumor microenvironment. These data support clinical studies of defibrotide in combination with conventional and novel therapies to potentially improve patient outcome in multiple myeloma and other malignancies.

Preclinical Studies in Support of Defibrotide for the Treatment of Multiple Myeloma and Other Neoplasias

PubMed Central

Mitsiades, Constantine S.; Rouleau, Cecile; Echart, Cinara; Menon, Krishna; Teicher, Beverly; Distaso, Maria; Palumbo, Antonio; Boccadoro, Mario; Anderson, Kenneth C.; Iacobelli, Massimo; Richardson, Paul G.

2015-01-01

Purpose of the study Defibrotide (DF), an orally bioavailable polydisperse oligonucleotide has promising activity in hepatic veno-occlusive disease (VOD), a stem cell transplantation-related toxicity, characterized by microangiopathy. The anti-thrombotic properties of DF and its minimal hemorrhagic risk could serve for treatment of cancer-associated thrombotic complications. Given its cytoprotective effect on endothelium, we investigated whether DF protects tumor cells from cytotoxic anti-tumor agents. Further, given its anti-adhesive properties, we evaluated whether DF modulates the protection conferred to multiple myeloma (MM) cells by bone marrow stromal cells (BMSCs). Methods-Results DF lacks significant single-agent in vitro cytotoxicity on MM or solid tumor cells and does not attenuate their in vitro response to dexamethasone, bortezomib, immunomodulatory thalidomide derivatives, and conventional chemotherapeutics, including melphalan and cyclophosphamide. Importantly, DF enhances in vivo chemosensitivity of MM and mammary carcinoma xenografts in animal models. In co-cultures of MM cells with BMSCs in vitro, DF enhances the MM cell sensitivity to melphalan and dexamethasone, decreases MM-BMSC adhesion and its sequelae, including NF-κB activation in MM and BMSCs, and associated cytokine production. Moreover, DF inhibits expression and/or function of key mediators of MM interaction with BMSC and endothelium, including heparanase, angiogenic cytokines and adhesion molecules. Conclusion Defibrotide’s in vivo chemosensitizing properties and lack of direct in vitro activity against tumor cells suggest that it favorably modulates antitumor interactions between BMSC and endothelia in the tumor microenvironment. These data support clinical studies of DF in combination with conventional and novel therapies to potentially improve patient outcome in MM and other malignancies. PMID:19228727

Preventing Pseudomonas aeruginosa and Chromobacterium violaceum infections by anti-adhesion-active components of edible seeds

PubMed Central

2012-01-01

Background Pseudomonas aeruginosa adhesion to animal/human cells for infection establishment involves adhesive proteins, including its galactose- and fucose-binding lectins PA-IL (LecA) and PA-IIL (LecB). The lectin binding to the target-cell receptors may be blocked by compatible glycans that compete with those of the receptors, functioning as anti-adhesion glycodecoys. The anti-adhesion treatment is of the utmost importance for abrogating devastating antibiotic-resistant P. aeruginosa infections in immunodeficient and cystic fibrosis (CF) patients. This strategy functions in nature in protecting embryos and neonates. We have shown that PA-IL, PA-IIL, and also CV-IIL (a PA-IIL homolog produced in the related pathogen Chromobacterium violaceum) are highly useful for revealing natural glycodecoys that surround embryos in diverse avian eggs and are supplied to neonates in milks and royal jelly. In the present study, these lectins were used as probes to search for seed embryo-protecting glycodecoys. Methods The lectin-blocking glycodecoy activities were shown by the hemagglutination-inhibition test. Lectin-binding glycoproteins were detected by Western blotting with peroxidase-labeled lectins. Results The present work reports the finding - by using PA-IL, PA-IIL, and CV-IIL - of rich glycodecoy activities of low (< 10 KDa) and high MW (> 10 kDa) compounds (including glycoproteins) in extracts of cashew, cocoa, coffee, pumpkin, and tomato seeds, resembling those of avian egg whites, mammal milks, and royal jelly. Conclusions Edible seed extracts possess lectin-blocking glycodecoys that might protect their embryos from infections and also might be useful for hampering human and animal infections. PMID:22336073

Effects of a Temperature-Sensitive, Anti-Adhesive Agent on the Reduction of Adhesion in a Rabbit Laminectomy Model

PubMed Central

Park, Jeong Woo; Cho, Tae Koo; Chun, Hyoung-Joon; Ryu, Je Il

2016-01-01

Objective A common cause of failure in laminectomy surgery is when epidural, peridural, or perineural adhesion occurs postoperatively. The purpose of this study is to examine the efficacy of a temperature-sensitive, anti-adhesive agent (TSAA agent), Guardix-SG®, as a mechanical barrier for the prevention or reduction of peridural scar adhesion in a rabbit laminectomy model. Methods Twenty-six mature rabbits were used for this study. Each rabbit underwent two separate laminectomies at lumbar vertebrae L3 and L6, left empty (the control group) and applied 2 mL of the TSAA agent (the experimental group), respectively. Invasive scar formation or inflammation after laminectomy was quantitatively evaluated by measuring the thickness of the dura, the distance from the surface of dura to the scar tissues, the number of inflammatory cells in the scar tissues at the laminectomy site, and the concentration of collagen in histological sections. Results At 6 weeks postsurgery, the dura was significantly thinner and the distance from the surface of dura to the scar tissues was greater in the experimental group than in the control group (p=0.04 and p=0.01). The number of inflammatory cells was not significantly different in the two groups (p=0.08), although the mean number of inflammatory cells was relatively lower in the experimental group than in the control group. Conclusion The current study suggests that the TSAA agent, Guardix-SG®, could be useful as an interpositional physical barrier after laminectomy for the prevention or reduction of adhesion. PMID:27226857

Glycosyltransferase-mediated Sweet Modification in Oral Streptococci.

PubMed

Zhu, F; Zhang, H; Wu, H

2015-05-01

Bacterial glycosyltransferases play important roles in bacterial fitness and virulence. Oral streptococci have evolved diverse strategies to survive and thrive in the carbohydrate-rich oral cavity. In this review, we discuss 2 important biological processes mediated by 2 distinct groups of glycosyltransferases in oral streptococci that are important for bacterial colonization and virulence. The first process is the glycosylation of highly conserved serine-rich repeat adhesins by a series of glycosyltransferases. Using Streptococcus parasanguinis as a model, we highlight new features of several glycosyltransferases that sequentially modify the serine-rich glycoprotein Fap1. Distinct features of a novel glycosyltransferase fold from a domain of unknown function 1792 are contrasted with common properties of canonical glycosyltransferases. The second biological process we cover is involved in building sticky glucan matrix to establish cariogenic biofilms by an important opportunistic pathogen Streptococcus mutans through the action of a family of 3 glucosyltransferases. We focus on discussing the structural feature of this family as a glycoside hydrolase family of enzymes. While the 2 processes are distinct, they all produce carbohydrate-coated biomolecules, which enable bacteria to stick better in the complex oral microbiome. Understanding the making of the sweet modification presents a unique opportunity to develop novel antiadhesion and antibiofilm strategies to fight infections by oral streptococci and beyond. © International & American Associations for Dental Research 2015.

Glycosyltransferase-mediated Sweet Modification in Oral Streptococci

PubMed Central

Zhu, F.; Zhang, H.

2015-01-01

Bacterial glycosyltransferases play important roles in bacterial fitness and virulence. Oral streptococci have evolved diverse strategies to survive and thrive in the carbohydrate-rich oral cavity. In this review, we discuss 2 important biological processes mediated by 2 distinct groups of glycosyltransferases in oral streptococci that are important for bacterial colonization and virulence. The first process is the glycosylation of highly conserved serine-rich repeat adhesins by a series of glycosyltransferases. Using Streptococcus parasanguinis as a model, we highlight new features of several glycosyltransferases that sequentially modify the serine-rich glycoprotein Fap1. Distinct features of a novel glycosyltransferase fold from a domain of unknown function 1792 are contrasted with common properties of canonical glycosyltransferases. The second biological process we cover is involved in building sticky glucan matrix to establish cariogenic biofilms by an important opportunistic pathogen Streptococcus mutans through the action of a family of 3 glucosyltransferases. We focus on discussing the structural feature of this family as a glycoside hydrolase family of enzymes. While the 2 processes are distinct, they all produce carbohydrate-coated biomolecules, which enable bacteria to stick better in the complex oral microbiome. Understanding the making of the sweet modification presents a unique opportunity to develop novel antiadhesion and antibiofilm strategies to fight infections by oral streptococci and beyond. PMID:25755271

Cationic Copolymerization of 3,3-Bis(hydroxymethyl)oxetane and Glycidol: Biocompatible Hyperbranched Polyether Polyols with High Content of Primary Hydroxyl Groups.

PubMed

Christ, Eva-Maria; Hobernik, Dominika; Bros, Matthias; Wagner, Manfred; Frey, Holger

2015-10-12

The cationic ring-opening copolymerization of 3,3-bis(hydroxymethyl)oxetane (BHMO) with glycidol using different comonomer ratios (BHMO content from 25 to 90%) and BF3OEt2 as an initiator has been studied. Apparent molecular weights of the resulting hyperbranched polyether copolymers ranged from 1400 to 3300 g mol(-1) (PDI: 1.21-1.48; method: SEC, linear PEG standards). Incorporation of both comonomers is evidenced by MALDI-TOF mass spectroscopy. All hyperbranched polyether polyols with high content of primary hydroxyl groups portray good solubility in water, which correlates with an increasing content of glycerol units. Detailed NMR characterization was employed to elucidate the copolymer microstructures. Kinetic studies via FTIR demonstrated a weak gradient-type character of the copolymers. MTT assays of the copolymers (up to 100 μg mL(-1)) on HEK and fibroblast cell lines (3T3, L929, WEHI) as well as viability tests on the fibroblast cells were carried out to assess the biocompatibility of the materials, confirming excellent biocompatibility. Transfection efficiency characterization by flow cytometry and confocal laser microscopy demonstrated cellular uptake of the copolymers. Antiadhesive properties of the materials on surfaces were assessed by adhesion assays with fibroblast cells.

Surfactant-free Colloidal Particles with Specific Binding Affinity

PubMed Central

2017-01-01

Colloidal particles with specific binding affinity are essential for in vivo and in vitro biosensing, targeted drug delivery, and micrometer-scale self-assembly. Key to these techniques are surface functionalizations that provide high affinities to specific target molecules. For stabilization in physiological environments, current particle coating methods rely on adsorbed surfactants. However, spontaneous desorption of these surfactants typically has an undesirable influence on lipid membranes. To address this issue and create particles for targeting molecules in lipid membranes, we present here a surfactant-free coating method that combines high binding affinity with stability at physiological conditions. After activating charge-stabilized polystyrene microparticles with EDC/Sulfo-NHS, we first coat the particles with a specific protein and subsequently covalently attach a dense layer of poly(ethyelene) glycol. This polymer layer provides colloidal stability at physiological conditions as well as antiadhesive properties, while the protein coating provides the specific affinity to the targeted molecule. We show that NeutrAvidin-functionalized particles bind specifically to biotinylated membranes and that Concanavalin A-functionalized particles bind specifically to the glycocortex of Dictyostelium discoideum cells. The affinity of the particles changes with protein density, which can be tuned during the coating procedure. The generic and surfactant-free coating method reported here transfers the high affinity and specificity of a protein onto colloidal polystyrene microparticles. PMID:28847149

Inhibition of P-fimbriated Escherichia coli adhesion by multivalent galabiose derivatives studied by a live-bacteria application of surface plasmon resonance.

PubMed

Salminen, Annika; Loimaranta, Vuokko; Joosten, John A F; Khan, A Salam; Hacker, Jörg; Pieters, Roland J; Finne, Jukka

2007-09-01

Uropathogenic P-fimbriated Escherichia coli adheres to host cells by specific adhesins recognizing galabiose (Galalpha1-4Gal)-containing structures on cell surfaces. In search of agents inhibiting this first step of infection, the inhibition potency of a set of synthetic mono- and multivalent galabiose compounds was evaluated. In order to mimic the flow conditions of natural infections, a live-bacteria application of surface plasmon resonance (SPR) was established. For the measurement of the binding of E. coli to a surface containing galabiose, live bacteria were injected over the flow cell, and the inhibition of adhesion caused by the galabiose inhibitors was recorded. Quantitative binding data were recorded in real-time for each inhibitor. The results were compared with those of conventional static haemagglutination and ELISA-based cell adhesion assays. Compared with the Gram-positive Streptococcus suis bacteria, which also bind to galabiose and whose binding inhibition is strongly dependent on the multivalency of the inhibitor, E. coli inhibition was only moderately affected by the valency. However, a novel octavalent compound was found to be the most effective inhibitor of E. coli PapG(J96) adhesion, with an IC50 value of 2 microM. Measurement of bacterial adhesion by SPR is an efficient way to characterize the adhesion of whole bacterial cells and allows the characterization of the inhibitory potency of adhesion inhibitors under dynamic flow conditions. Under these conditions, multivalency increases the anti-adhesion potency of galabiose-based inhibitors of P-fimbriated E. coli adhesion and provides a promising approach for the design of high-affinity anti-adhesion agents.

Numerical modeling of mechanical behavior of multilayered composite plates with defects under static loading

NASA Astrophysics Data System (ADS)

Korepanov, V. V.; Serovaev, G. S.

2017-06-01

Evaluation of the mechanical state of a structure or its components in the process of operation based on detection of internal damages (damage detection) becomes especially important in such rapidly developing spheres of production as machine building, aerospace industry, etc. One of the most important features of these industries is the application of new types of materials among which polymer based composite materials occupy a significant position. Hence, they must have sufficient operational rigidity and strength. However, defects of various kinds may arise during the manufacture. Delamination is the most common defect in structures made from composite materials and represents a phenomenon that involves the complex fracture of layers and interlayer compounds. Among the reasons of delamination occurrence are: disposition of anti-adhesive lubricants, films; insufficient content of binder, high content of volatile elements; violation of the molding regime; poor quality of anti-adhesive coating on the surface of the tooling. One of the effective methods for analyzing the influence of defects is numerical simulation. With the help of numerical methods, it is possible to track the evolution of various parameters when the defect size and quantity change. In the paper, a multilayered plate of an equally resistant carbon fiber reinforced plastic was considered, with a thickness of each layer equal to 0.2 mm. Various static loading cases are studied: uniaxial tension, three and four-point bending. For each type of loading, a numerical calculation of the stress-strain state was performed for healthy and delaminated plates, with different number and size of the defects. Contact interaction between adjacent surfaces in the zone of delamination was taken into account.

A proteinaceous fraction of wheat bran may interfere in the attachment of enterotoxigenic E. coli K88 (F4+) to porcine epithelial cells.

PubMed

González-Ortiz, Gemma; Bronsoms, Sílvia; Quarles Van Ufford, H C; Halkes, S Bart A; Virkola, Ritva; Liskamp, Rob M J; Beukelman, Cees J; Pieters, Roland J; Pérez, José Francisco; Martín-Orúe, Susana María

2014-01-01

Wheat bran (WB) from Triticum aestivum has many beneficial effects on human health. To the best of our knowledge, very little has been published about its ability to prevent pathogenic bacterial adhesion in the intestine. Here, a WB extract was fractionated using different strategies, and the obtained fractions were tested in different in vitro methodologies to evaluate their interference in the attachment of enterotoxigenic Escherichia coli (ETEC) K88 to intestinal porcine epithelial cells (IPEC-J2) with the aim of identifying the putative anti-adhesive molecules. It was found that a proteinaceous compound in the >300-kDa fraction mediates the recognition of ETEC K88 to IPEC-J2. Further fractionation of the >300-kDa sample by size-exclusion chromatography showed several proteins below 90 kDa, suggesting that the target protein belongs to a high-molecular-weight (MW) multi-component protein complex. The identification of some relevant excised bands was performed by mass spectrometry (MS) and mostly revealed the presence of various protease inhibitors (PIs) of low MW: Serpin-Z2B, Class II chitinase, endogenous alpha-amylase/subtilisin inhibitor and alpha-amylase/trypsin inhibitor CM3. Furthermore, an incubation of the WB extract with ETEC K88 allowed for the identification of a 7S storage protein globulin of wheat, Globulin 3 of 66 kDa, which may be one of the most firmly attached WB proteins to ETEC K88 cells. Further studies should be performed to gain an understanding of the molecular recognition of the blocking process that takes place. All gathered information can eventually pave the way for the development of novel anti-adhesion therapeutic agents to prevent bacterial pathogenesis.

Bacterial Adhesion of Streptococcus suis to Host Cells and Its Inhibition by Carbohydrate Ligands

PubMed Central

Kouki, Annika; Pieters, Roland J.; Nilsson, Ulf J.; Loimaranta, Vuokko; Finne, Jukka; Haataja, Sauli

2013-01-01

Streptococcus suis is a Gram-positive bacterium, which causes sepsis and meningitis in pigs and humans. This review examines the role of known S. suis virulence factors in adhesion and S. suis carbohydrate-based adhesion mechanisms, as well as the inhibition of S. suis adhesion by anti-adhesion compounds in in vitro assays. Carbohydrate-binding specificities of S. suis have been identified, and these studies have shown that many strains recognize Galα1-4Gal-containing oligosaccharides present in host glycolipids. In the era of increasing antibiotic resistance, new means to treat infections are needed. Since microbial adhesion to carbohydrates is important to establish disease, compounds blocking adhesion could be an alternative to antibiotics. The use of oligosaccharides as drugs is generally hampered by their relatively low affinity (micromolar) to compete with multivalent binding to host receptors. However, screening of a library of chemically modified Galα1-4Gal derivatives has identified compounds that inhibit S. suis adhesion in nanomolar range. Also, design of multivalent Galα1-4Gal-containing dendrimers has resulted in a significant increase of the inhibitory potency of the disaccharide. The S. suis adhesin binding to Galα1-4Gal-oligosaccharides, Streptococcal adhesin P (SadP), was recently identified. It has a Galα1-4Gal-binding N-terminal domain and a C-terminal LPNTG-motif for cell wall anchoring. The carbohydrate-binding domain has no homology to E. coli P fimbrial adhesin, which suggests that these Gram-positive and Gram-negative bacterial adhesins recognizing the same receptor have evolved by convergent evolution. SadP adhesin may represent a promising target for the design of anti-adhesion ligands for the prevention and treatment of S. suis infections. PMID:24833053

Quantitative comparison of cancer and normal cell adhesion using organosilane monolayer templates: an experimental study on the anti-adhesion effect of green-tea catechins.

PubMed

Sakamoto, Rumi; Kakinuma, Eisuke; Masuda, Kentaro; Takeuchi, Yuko; Ito, Kosaku; Iketaki, Kentaro; Matsuzaki, Takahisa; Nakabayashi, Seiichiro; Yoshikawa, Hiroshi Y; Yamamoto, Hideaki; Sato, Yuko; Tanii, Takashi

2016-09-01

The main constituent of green tea, (-)-Epigallocatechin-3-O-gallate (EGCG), is known to have cancer-specific chemopreventive effects. In the present work, we investigated how EGCG suppresses cell adhesion by comparing the adhesion of human pancreatic cancer cells (AsPC-1 and BxPC-3) and their counterpart, normal human embryonic pancreas-derived cells (1C3D3), in catechin-containing media using organosilane monolayer templates (OMTs). The purpose of this work is (1) to evaluate the quantitativeness in the measurement of cell adhesion with the OMT and (2) to show how green-tea catechins suppress cell adhesion in a cancer-specific manner. For the first purpose, the adhesion of cancer and normal cells was compared using the OMT. The cell adhesion in different type of catechins such as EGCG, (-)-Epicatechin-3-O-gallate (ECG) and (-)-Epicatechin (EC) was also evaluated. The measurements revealed that the anti-adhesion effect of green-tea catechins is cancer-specific, and the order is EGCG≫ECG>EC. The results agree well with the data reported to date, showing the quantitativeness of the new method. For the second purpose, the contact area of cells on the OMT was measured by reflection interference contrast microscopy. The cell-OMT contact area of cancer cells decreases with increasing EGCG concentration, whereas that of normal cells remains constant. The results reveal a twofold action of EGCG on cancer cell adhesion-suppressing cell attachment to a candidate adhesion site and decreasing the contact area of the cells-and validates the use of OMT as a tool for screening cancer cell adhesion.

Anti-adhesive and pro-apoptotic effects of 2-hydroxyethyl methacrylate on human gingival fibroblasts co-cultured with Streptococcus mitis strains

PubMed Central

Zara, S; Di Giulio, M; D’Ercole, S; Cellini, L; Cataldi, A

2011-01-01

Aim To evaluate and observe the cellular reactions that occur during the interaction/integration between 2-hydroxyethyl methacrylate/host tissue/microbial environment, in a co-culture of human gingival fibroblasts (HGF) and Streptococcus mitis strains. Methodology Streptococcus mitis were cultured with strains in the presence of 3 mmol L−1 HEMA for 48 h and 72 h. Cytotoxicity was evaluated by the trypan blue dye exclusion test. Apoptosis was evaluated by TUNEL analysis. Adhesion was evaluated by immunofluorescence and western blot analyses. Quantitative analyses of the results were acquired by Qwin Plus 3.5 and QuantityOne I-D analysis software, respectively. The statistical significance of the results was evaluated using t-tests and linear regression tests. Results The trypan blue dye test revealed 47.3% and 46.5% of dead fibroblasts after 48 and 72 h HEMA treatment, respectively, while bacterial viability was not influenced by the presence of HEMA and fibroblasts. The expression of pro-collagen I, involved in fibroblast adhesion, in untreated samples ranged from 12.49% to 6.91% of the positive area after 48 and 72 h, respectively, dropping to below 2% of the positive area in the other experimental conditions. Unlike the trypan blue test, co-cultured samples treated with HEMA showed 20% and 25% versus 17% and 21% (after 48 and 72 h, respectively) of apoptotic cells. Conclusions The evidence for HEMA toxicity and anti-adhesive effects against eukaryotic cells was reduced in the presence of bacteria, suggesting that dental resins should be well polymerized to avoid the spread of toxic monomers within the mouth. PMID:21902700

Inhibitory effect of dimeric beta peptide on the recurrence and metastasis of hepatocellular carcinoma in vitro and in mice.

PubMed

Wang, Song-Mei; Zhu, Jun; Pan, Luan-Feng; Liu, Yin-Kun

2008-05-21

To block the adhesion of tumor cells to the extracellular matrix, and prevent tumor metastasis and recurrence, the dimer of the beta peptide (DLYYLMDLSYSMKGGDLYYLMDLSYSMK, beta2) was designed and synthesized and its anti-adhesion and anti-invasion effects on hepatocellular carcinoma cells were assessed. Additionally, its influence on the metastasis and recurrence of mouse hepatocellular carcinoma was measured. The anti-adhesion effect of beta2 on the highly metastatic hepatocellular carcinoma cell line HCCLM6 cells and fibronectin (FN) was assayed by the MTT assay. The inhibition of invasion of HCCLM6 cells by beta2 was observed using a Transwell (modified Boyden chamber) and matrigel. Using the hepatocellular carcinoma metastasis model and LCI-D20 nude mice, the influence of beta2 on the metastasis and recurrence of hepatocellular carcinoma after early resection was investigated. HCCLM6 cells co-incubated with 100 mumol/L, 50 micromol/L, 20 micromol/L or 10 micromol/L beta2 for 3 h showed an obvious decrease in adhesion to FN. The adhesion inhibition ratios were 11.8%, 21.7%, 29.6% and 48.7%, respectively. Additionally, HCCLM6 cells cultured with 100 mumol/L beta2 had a dramatic decrease in cell invasion. beta2 was also observed to inhibit the incisal edge recurrence and the distant metastasis of nude mice hepatocellular carcinoma after early resection (P < 0.05). The beta2 peptide can specifically block the adhesion and invasion of HCCLM6 cells, and can inhibit HCC recurrence and metastasis of LCI-D20 model posthepatectomy in vivo. Thus, beta2 should be further studied as a new anti-tumor drug.

The membrane mucin MUC4 is elevated in breast tumor lymph node metastases relative to matched primary tumors and confers aggressive properties to breast cancer cells.

PubMed

Workman, Heather C; Miller, Jamie K; Ingalla, Ellen Q; Kaur, Rouminder P; Yamamoto, Diane I; Beckett, Laurel A; Young, Lawrence Jt; Cardiff, Robert D; Borowsky, Alexander D; Carraway, Kermit L; Sweeney, Colleen; Carraway, Kermit L

2009-01-01

Previous studies indicate that overexpression of the membrane-associated mucin MUC4 is potently anti-adhesive to cultured tumor cells, and suppresses cellular apoptotic response to a variety of insults. Such observations raise the possibility that MUC4 expression could contribute to tumor progression or metastasis, but the potential involvement of MUC4 in breast cancer has not been rigorously assessed. The present study aimed to investigate the expression of the membrane mucin MUC4 in normal breast tissue, primary breast tumors and lymph node metastases, and to evaluate the role of MUC4 in promoting the malignant properties of breast tumor cells. MUC4 expression levels in patient-matched normal and tumor breast tissue was initially examined by immunoblotting lysates of fresh frozen tissue samples with a highly specific preparation of anti-MUC4 monoclonal antibody 1G8. Immunohistochemical analysis was then carried out using tissue microarrays encompassing patient-matched normal breast tissue and primary tumors, and patient-matched lymph node metastases and primary tumors. Finally, shRNA-mediated knockdown was employed to assess the contribution of MUC4 to the cellular growth and malignancy properties of JIMT-1 breast cancer cells. Immunoblotting and immunohistochemistry revealed that MUC4 levels are suppressed in the majority (58%, p < 0.001) of primary tumors relative to patient-matched normal tissue. On the other hand, lymph node metastatic lesions from 37% (p < 0.05) of patients expressed higher MUC4 protein levels than patient-matched primary tumors. MUC4-positive tumor emboli were often found in lymphovascular spaces of lymph node metastatic lesions. shRNA-mediated MUC4 knockdown compromised the migration, proliferation and anoikis resistance of JIMT-1 cells, strongly suggesting that MUC4 expression actively contributes to cellular properties associated with breast tumor metastasis. Our observations suggest that after an initial loss of MUC4 levels during the transition of normal breast tissue to primary tumor, the re-establishment of elevated MUC4 levels confers an advantage to metastasizing breast tumor cells by promoting the acquisition of cellular properties associated with malignancy.

Antiadhesion agents against Gram-positive pathogens.

PubMed

Cascioferro, Stella; Cusimano, Maria Grazia; Schillaci, Domenico

2014-01-01

A fundamental step of Gram-positive pathogenesis is the bacterial adhesion to the host tissue involving interaction between bacterial surface molecules and host ligands. This review is focused on antivirulence compounds that target Gram-positive adhesins and on their potential development as therapeutic agents alternative or complementary to conventional antibiotics in the contrast of pathogens. In particular, compounds that target the sortase A, wall theicoic acid inhibitors, carbohydrates able to bind bacterial proteins and proteins capable of influencing the bacterial adhesion, were described. We further discuss the advantages and disadvantages of this strategy in the development of novel antimicrobials and the future perspective of this research field still at its first steps.

Botanical medicines for the urinary tract.

PubMed

Yarnell, Eric

2002-11-01

Four important categories of urologic herbs, their history, and modern scientific investigations regarding them are reviewed. Botanical diuretics are discussed with a focus on Solidago spp (goldenrod) herb, Levisticum officinale (lovage) root, Petroselinum crispus (parsley) fruit, and Urtica dioica (stinging nettle) herb. Urinary antiseptic and anti-adhesion herbs, particularly Arctostaphylos uva-ursi (uva-uri) leaf, Juniperus spp (juniper) leaf, and Vaccinium macrocarpon (cranberry) fruit are reviewed. The antinephrotoxic botanicals Rheum palmatum (Chinese rhubarb) root and Lespedeza capitata (round-head lespedeza) herb are surveyed, followed by herbs for symptoms of benign prostatic hyperplasia, most notably Serenoa repens (saw palmetto) fruit, Urtica dioica root, and Prunus africana (pygeum) bark.

Enhanced antiadhesive properties of chitosan/hyaluronic acid polyelectrolyte multilayers driven by thermal annealing: Low adherence for mammalian cells and selective decrease in adhesion for Gram-positive bacteria.

PubMed

Muzzio, Nicolás E; Pasquale, Miguel A; Diamanti, Eleftheria; Gregurec, Danijela; Moro, Marta Martinez; Azzaroni, Omar; Moya, Sergio E

2017-11-01

The development of antifouling coatings with restricted cell and bacteria adherence is fundamental for many biomedical applications. A strategy for the fabrication of antifouling coatings based on the layer-by-layer assembly and thermal annealing is presented. Polyelectrolyte multilayers (PEMs) assembled from chitosan and hyaluronic acid were thermally annealed in an oven at 37°C for 72h. The effect of annealing on the PEM properties and topography was studied by atomic force microscopy, ζ-potential, circular dichroism and contact angle measurements. Cell adherence on PEMs before and after annealing was evaluated by measuring the cell spreading area and aspect ratio for the A549 epithelial, BHK kidney fibroblast, C2C12 myoblast and MC-3T3-E1 osteoblast cell lines. Chitosan/hyaluronic acid PEMs show a low cell adherence that decreases with the thermal annealing, as observed from the reduction in the average cell spreading area and more rounded cell morphology. The adhesion of S. aureus (Gram-positive) and E. coli (Gram-negative) bacteria strains was quantified by optical microscopy, counting the number of colony-forming units and measuring the light scattering of bacteria suspension after detachment from the PEM surface. A 20% decrease in bacteria adhesion was selectively observed in the S. aureus strain after annealing. The changes in mammalian cell and bacteria adhesion correlate with the changes in topography of the chitosan/hyaluronic PEMs from a rough fibrillar 3D structure to a smoother and planar surface after thermal annealing. Copyright © 2017. Published by Elsevier B.V.

Microencapsulation of rifampicin for the prevention of endophthalmitis: In vitro release studies and antibacterial assessment.

PubMed

Lee, Mi Yeon; Bourgeois, Sandrine; Almouazen, Eyad; Pelletier, Jocelyne; Renaud, François; Fessi, Hatem; Kodjikian, Laurent

2016-05-30

Rifampicin encapsulated microparticles were designed for intraocular injection after cataract surgery to prevent postoperative endophthalmitis. Microparticles were formulated by emulsification diffusion method using poly(lactic acid-co-glycolic acid) (PLGA) as polymer in order to propose a new form of rifampicin that overcome its limitations in intraocular delivery. Depending on processing formulation, different types of microparticles were prepared, characterized and evaluated by in vitro release studies. Two types of microparticles were selected to get a burst release of rifampicin, to reach minimal inhibitory concentrations to inhibit 90% of Staphylococcus epidermidis mainly involved in postoperative endophthalmitis, combined with a sustained release to maintain rifampicin concentration over 24h. The antibacterial activity and antiadhesive property on intraocular lenses were evaluated on S. epidermidis. Microparticles, with a rapid rifampicin release profile, showed an effect towards bacteria development similar to free rifampicin over 48h. However, slow-release profile microparticles exhibited a similar antibacterial effect during the first 24h, and were able to destroy all the S epidermidis in the medium after 30h. The association of the two formulations allowed obtaining interesting antibacterial profile. Moreover, rifampicin-loaded microparticles have shown a very efficient anti-adherent effect of S. epidermidis on intraocular lenses at 24h. These results propose rifampicin microparticles as suitable for antibioprophylaxis of the postoperative endophthalmitis. Copyright © 2016 Elsevier B.V. All rights reserved.

Fabrication of nonfouling, bactericidal, and bacteria corpse release multifunctional surface through surface-initiated RAFT polymerization.

PubMed

Wang, Bailiang; Ye, Zi; Tang, Yihong; Han, Yuemei; Lin, Quankui; Liu, Huihua; Chen, Hao; Nan, Kaihui

Infections after surgery or endophthalmitis are potentially blinding complications caused by bacterial adhesion and subsequent biofilm formation on the intraocular lens. Neither single-function anti-adhesion surface nor contacting killing surface can exhibit ideal antibacterial function. In this work, a novel (2-(dimethylamino)-ethyl methacrylate- co -2-methacryloyloxyethyl phosphorylcholine) (p (DMAEMA- co -MPC)) brush was synthesized by "grafting from" method through reversible-addition fragmentation chain transfer polymerization. 1-Bromoheptane was used to quaternize the p (DMAEMA- co -MPC) brush coating and to endow the surface with bactericidal function. The success of the surface functionalization was confirmed by atomic force microscopy, water contact angle, and spectroscopic ellipsometry. The quaternary ammonium salt units were employed as efficient disinfection that can eliminate bacteria through contact killing, whereas the 2-methacryloyloxyethyl phosphorylcholine units were introduced to suppress unwanted nonspecific adsorption. The functionalized poly(dimethyl siloxane) surfaces showed efficiency in reducing bovine serum albumin adsorption and in inhibiting bacteria adhesion and biofilm formation. The copolymer brushes also demonstrated excellent bactericidal function against gram-positive ( Staphylococcus aureus ) bacteria measured by bacteria live/dead staining and shake-flask culture methods. The surface biocompatibility was evaluated by morphology and activity measurement with human lens epithelial cells in vitro. The achievement of the p (DMAEMA + - co -MPC) copolymer brush coating with nonfouling, bactericidal, and bacteria corpse release properties can be used to modify intraocular lenses.

Green tea polyphenol tailors cell adhesivity of RGD displaying surfaces: multicomponent models monitored optically

PubMed Central

Peter, Beatrix; Farkas, Eniko; Forgacs, Eniko; Saftics, Andras; Kovacs, Boglarka; Kurunczi, Sandor; Szekacs, Inna; Csampai, Antal; Bosze, Szilvia; Horvath, Robert

2017-01-01

The interaction of the anti-adhesive coating, poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) and its Arg-Gly-Asp (RGD) functionalized form, PLL-g-PEG-RGD, with the green tea polyphenol, epigallocatechin-gallate (EGCg) was in situ monitored. After, the kinetics of cellular adhesion on the EGCg exposed coatings were recorded in real-time. The employed plate-based waveguide biosensor is applicable to monitor small molecule binding and sensitive to sub-nanometer scale changes in cell membrane position and cell mass distribution; while detecting the signals of thousands of adhering cells. The combination of this remarkable sensitivity and throughput opens up new avenues in testing complicated models of cell-surface interactions. The systematic studies revealed that, despite the reported excellent antifouling properties of the coatings, EGCg strongly interacted with them, and affected their cell adhesivity in a concentration dependent manner. Moreover, the differences between the effects of the fresh and oxidized EGCg solutions were first demonstrated. Using a semiempirical quantumchemical method we showed that EGCg binds to the PEG chains of PLL-g-PEG-RGD and effectively blocks the RGD sites by hydrogen bonds. The calculations supported the experimental finding that the binding is stronger for the oxidative products. Our work lead to a new model of polyphenol action on cell adhesion ligand accessibility and matrix rigidity. PMID:28186133

Inhibition of type 1 fimbriae-mediated Escherichia coli adhesion and biofilm formation by trimeric cluster thiomannosides conjugated to diamond nanoparticles.

PubMed

Khanal, Manakamana; Larsonneur, Fanny; Raks, Victoriia; Barras, Alexandre; Baumann, Jean-Sébastien; Martin, Fernando Ariel; Boukherroub, Rabah; Ghigo, Jean-Marc; Ortiz Mellet, Carmen; Zaitsev, Vladimir; Garcia Fernandez, Jose M; Beloin, Christophe; Siriwardena, Aloysius; Szunerits, Sabine

2015-02-14

Recent advances in nanotechnology have seen the development of a number of microbiocidal and/or anti-adhesive nanoparticles displaying activity against biofilms. In this work, trimeric thiomannoside clusters conjugated to nanodiamond particles (ND) were targeted for investigation. NDs have attracted attention as a biocompatible nanomaterial and we were curious to see whether the high mannose glycotope density obtained upon grouping monosaccharide units in triads might lead to the corresponding ND-conjugates behaving as effective inhibitors of E. coli type 1 fimbriae-mediated adhesion as well as of biofilm formation. The required trimeric thiosugar clusters were obtained through a convenient thiol-ene "click" strategy and were subsequently conjugated to alkynyl-functionalized NDs using a Cu(I)-catalysed "click" reaction. We demonstrated that the tri-thiomannoside cluster-conjugated NDs (ND-Man3) show potent inhibition of type 1 fimbriae-mediated E. coli adhesion to yeast and T24 bladder cells as well as of biofilm formation. The biofilm disrupting effects demonstrated here have only rarely been reported in the past for analogues featuring such simple glycosidic motifs. Moreover, the finding that the tri-thiomannoside cluster (Man3N3) is itself a relatively efficient inhibitor, even when not conjugated to any ND edifice, suggests that alternative mono- or multivalent sugar-derived analogues might also be usefully explored for E. coli-mediated biofilm disrupting properties.

Green tea polyphenol tailors cell adhesivity of RGD displaying surfaces: multicomponent models monitored optically.

PubMed

Peter, Beatrix; Farkas, Eniko; Forgacs, Eniko; Saftics, Andras; Kovacs, Boglarka; Kurunczi, Sandor; Szekacs, Inna; Csampai, Antal; Bosze, Szilvia; Horvath, Robert

2017-02-10

The interaction of the anti-adhesive coating, poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) and its Arg-Gly-Asp (RGD) functionalized form, PLL-g-PEG-RGD, with the green tea polyphenol, epigallocatechin-gallate (EGCg) was in situ monitored. After, the kinetics of cellular adhesion on the EGCg exposed coatings were recorded in real-time. The employed plate-based waveguide biosensor is applicable to monitor small molecule binding and sensitive to sub-nanometer scale changes in cell membrane position and cell mass distribution; while detecting the signals of thousands of adhering cells. The combination of this remarkable sensitivity and throughput opens up new avenues in testing complicated models of cell-surface interactions. The systematic studies revealed that, despite the reported excellent antifouling properties of the coatings, EGCg strongly interacted with them, and affected their cell adhesivity in a concentration dependent manner. Moreover, the differences between the effects of the fresh and oxidized EGCg solutions were first demonstrated. Using a semiempirical quantumchemical method we showed that EGCg binds to the PEG chains of PLL-g-PEG-RGD and effectively blocks the RGD sites by hydrogen bonds. The calculations supported the experimental finding that the binding is stronger for the oxidative products. Our work lead to a new model of polyphenol action on cell adhesion ligand accessibility and matrix rigidity.

Multi-effect of the water-soluble Moringa oleifera lectin against Serratia marcescens and Bacillus sp.: antibacterial, antibiofilm and anti-adhesive properties.

PubMed

Moura, M C; Trentin, D S; Napoleão, T H; Primon-Barros, M; Xavier, A S; Carneiro, N P; Paiva, P M G; Macedo, A J; Coelho, L C B B

2017-10-01

To evaluate the antibiofilm potential of water-soluble Moringa oleifera seed lectin (WSMoL) on Serratia marcescens and Bacillus sp. WSMoL inhibited biofilm formation by S. marcescens at concentrations lower than 2·6 μg ml -1 and impaired bacterial growth at higher concentrations, avoiding biofilm formation. For Bacillus sp., the lectin inhibited bacterial growth at all concentrations. The antibiofilm action of WSMoL is associated with damage to bacterial cells. WSMoL did not disrupt preformed S. marcescens biofilms but was able to damage cells inside them. On the other hand, the lectin reduced the number of cells in Bacillus sp. biofilm treated with it. WSMoL was able to control biofilm formation when immobilized on glass surface (116 μg cm -2 ), damaging S. marcescens cells and avoiding adherence of Bacillus sp. cells on glass. The Bacillus sp. isolate is member of Bacillus subtilis species complex and closely related to species of the conspecific 'amyloliquefaciens' group. WSMoL prevented biofilm development by S. marcescens and Bacillus sp. and the antibiofilm effect is also observed when the lectin is immobilized on glass. Taking together, our results provide support to the potential use of WSMoL for controlling biofilm formation by bacteria. © 2017 The Society for Applied Microbiology.

Sirolimus-coated, poly(L-lactic acid)-modified polypropylene mesh with minimal intra-peritoneal adhesion formation in a rat model.

PubMed

Lu, S; Hu, W; Zhang, Z; Ji, Z; Zhang, T

2018-05-18

This study evaluated the manufacturing method and anti-adhesion properties of a new composite mesh in the rat model, which was made from sirolimus (SRL) grafts on a poly(L-lactic acid) (PLLA)-modified polypropylene (PP) hernia mesh. PLLA was first grafted onto argon-plasma-treated native PP mesh through catalysis of stannous chloride. SRL was grafted onto the surface of PP-PLLA meshes using catalysis of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and 4-dimethylaminopyridine (DMAP) in a CH 2 Cl 2 solvent. Sprague-Dawley female rats received either SRL-coated meshes, PP-PLLA meshes, or native PP meshes to repair abdominal wall defects. At different intervals, rats were euthanized by a lethal dose of chloral hydrate and adhesion area and tenacity were evaluated. Sections of the mesh with adjacent tissues were assessed histologically. Attenuated total reflection Fourier transformed infrared (ATR-FTIR) spectroscopy indicated the existence of a C=O group absorption peak (1724.1 cm -1 ), and scanning electron microscope morphological analysis indicated that the surface of the PP mesh was covered with SRL. Compared to the native PP meshes and PP-PLLA meshes, SRL-coated meshes demonstrated the greatest ability to decrease the formation of adhesions (P < 0.05) and inflammation. The SRL-coated composite mesh showed minimal formation of intra-abdominal adhesions in a rat model of abdominal wall defect repair.

Fabrication of nonfouling, bactericidal, and bacteria corpse release multifunctional surface through surface-initiated RAFT polymerization

PubMed Central

Wang, Bailiang; Ye, Zi; Tang, Yihong; Han, Yuemei; Lin, Quankui; Liu, Huihua; Chen, Hao; Nan, Kaihui

2017-01-01

Infections after surgery or endophthalmitis are potentially blinding complications caused by bacterial adhesion and subsequent biofilm formation on the intraocular lens. Neither single-function anti-adhesion surface nor contacting killing surface can exhibit ideal antibacterial function. In this work, a novel (2-(dimethylamino)-ethyl methacrylate-co-2-methacryloyloxyethyl phosphorylcholine) (p (DMAEMA-co-MPC)) brush was synthesized by “grafting from” method through reversible–addition fragmentation chain transfer polymerization. 1-Bromoheptane was used to quaternize the p (DMAEMA-co-MPC) brush coating and to endow the surface with bactericidal function. The success of the surface functionalization was confirmed by atomic force microscopy, water contact angle, and spectroscopic ellipsometry. The quaternary ammonium salt units were employed as efficient disinfection that can eliminate bacteria through contact killing, whereas the 2-methacryloyloxyethyl phosphorylcholine units were introduced to suppress unwanted nonspecific adsorption. The functionalized poly(dimethyl siloxane) surfaces showed efficiency in reducing bovine serum albumin adsorption and in inhibiting bacteria adhesion and biofilm formation. The copolymer brushes also demonstrated excellent bactericidal function against gram-positive (Staphylococcus aureus) bacteria measured by bacteria live/dead staining and shake-flask culture methods. The surface biocompatibility was evaluated by morphology and activity measurement with human lens epithelial cells in vitro. The achievement of the p (DMAEMA+-co-MPC) copolymer brush coating with nonfouling, bactericidal, and bacteria corpse release properties can be used to modify intraocular lenses. PMID:28053527

Action of Monomeric/Gemini Surfactants on Free Cells and Biofilm of Asaia lannensis.

PubMed

Koziróg, Anna; Kręgiel, Dorota; Brycki, Bogumił

2017-11-22

We investigated the biological activity of surfactants based on quaternary ammonium compounds: gemini surfactant hexamethylene-1,6-bis-( N,N -dimethyl- N -dodecylammonium bromide) (C6), synthesized by the reaction of N,N -dimethyl- N- dodecylamine with 1,6-dibromohexane, and its monomeric analogue dodecyltrimethylammonium bromide (DTAB). The experiments were performed with bacteria Asaia lannensis , a common spoilage in the beverage industry. The minimal inhibitory concentration (MIC) values were determined using the tube standard two-fold dilution method. The growth and adhesive properties of bacterial cells were studied in different culture media, and the cell viability was evaluated using plate count method. Both of the surfactants were effective against the bacterial strain, but the MIC of gemini compound was significantly lower. Both C6 and DTAB exhibited anti-adhesive abilities. Treatment with surfactants at or below MIC value decreased the number of bacterial cells that were able to form biofilm, however, the gemini surfactant was more effective. The used surfactants were also found to be able to eradicate mature biofilms. After 4 h of treatment with C6 surfactant at concentration 10 MIC, the number of bacterial cells was reduced by 91.8%. The results of this study suggest that the antibacterial activity of the gemini compound could make it an effective microbiocide against the spoilage bacteria Asaia sp. in both planktonic and biofilm stages.

Green tea polyphenol tailors cell adhesivity of RGD displaying surfaces: multicomponent models monitored optically

NASA Astrophysics Data System (ADS)

Peter, Beatrix; Farkas, Eniko; Forgacs, Eniko; Saftics, Andras; Kovacs, Boglarka; Kurunczi, Sandor; Szekacs, Inna; Csampai, Antal; Bosze, Szilvia; Horvath, Robert

2017-02-01

The interaction of the anti-adhesive coating, poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) and its Arg-Gly-Asp (RGD) functionalized form, PLL-g-PEG-RGD, with the green tea polyphenol, epigallocatechin-gallate (EGCg) was in situ monitored. After, the kinetics of cellular adhesion on the EGCg exposed coatings were recorded in real-time. The employed plate-based waveguide biosensor is applicable to monitor small molecule binding and sensitive to sub-nanometer scale changes in cell membrane position and cell mass distribution; while detecting the signals of thousands of adhering cells. The combination of this remarkable sensitivity and throughput opens up new avenues in testing complicated models of cell-surface interactions. The systematic studies revealed that, despite the reported excellent antifouling properties of the coatings, EGCg strongly interacted with them, and affected their cell adhesivity in a concentration dependent manner. Moreover, the differences between the effects of the fresh and oxidized EGCg solutions were first demonstrated. Using a semiempirical quantumchemical method we showed that EGCg binds to the PEG chains of PLL-g-PEG-RGD and effectively blocks the RGD sites by hydrogen bonds. The calculations supported the experimental finding that the binding is stronger for the oxidative products. Our work lead to a new model of polyphenol action on cell adhesion ligand accessibility and matrix rigidity.

Synthesis, characterization, and application of reversible PDLLA-PEG-PDLLA copolymer thermogels in vitro and in vivo

PubMed Central

Shi, Kun; Wang, Ya-Li; Qu, Ying; Liao, Jin-Feng; Chu, Bing-Yang; Zhang, Hua-Ping; Luo, Feng; Qian, Zhi-Yong

2016-01-01

In this study, a series of injectable thermoreversible and thermogelling PDLLA-PEG-PDLLA copolymers were developed and a systematic evaluation of the thermogelling system both in vitro and in vivo was performed. The aqueous PDLLA-PEG-PDLLA solutions above a critical gel concentration could transform into hydrogel spontaneously within 2 minutes around the body temperature in vitro or in vivo. Modulating the molecular weight, block length and polymer concentration could adjust the sol-gel transition behavior and the mechanical properties of the hydrogels. The gelation was thermally reversible due to the physical interaction of copolymer micelles and no crystallization formed during the gelation. Little cytotoxicity and hemolysis of this polymer was found, and the inflammatory response after injecting the hydrogel to small-animal was acceptable. In vitro and in vivo degradation experiments illustrated that the physical hydrogel could retain its integrity as long as several weeks and eventually be degraded by hydrolysis. A rat model of sidewall defect-bowel abrasion was employed, and a significant reduction of post-operative adhesion has been found in the group of PDLLA-PEG-PDLLA hydrogel-treated, compared with untreated control group and commercial hyaluronic acid (HA) anti-adhesion hydrogel group. As such, this PDLLA-PEG-PDLLA hydrogel might be a promising candidate of injectable biomaterial for medical applications. PMID:26752008

Systematic review of antimicrobial lock therapy for prevention of central-line-associated bloodstream infections in adult and pediatric cancer patients.

PubMed

Norris, LeAnn B; Kablaoui, Farah; Brilhart, Maggie K; Bookstaver, P Brandon

2017-09-01

Central venous catheter (CVC) use is commonplace in cancer patients. Antimicrobial lock therapy (ALT), the instillation of a concentrated antimicrobial solution into the catheter lumen, is one method for preventing infection among CVCs. This systematic review discusses the effectiveness and safety of prophylactic ALT in cancer patients with CVCs. A literature search was performed using the Medline database and Google Scholar from inception until April 2016. The following terms were used: 'antimicrobial lock solution', 'antibiotic lock solution', 'oncology', 'hematology', 'pediatrics', 'prevention', 'cancer', 'catheter related bloodstream infections', 'central-line associated bloodstream infection' (CLABSI) and 'central venous catheter'. Studies evaluating prophylactic ALT in cancer patients alone were eligible for inclusion. Case reports, case series and in-vitro studies were excluded. In total, 78 articles were identified. Following all exclusions, 13 articles (three adult and 10 pediatric) were selected for evaluation. The most common agents utilized were vancomycin with heparin; ethanol; taurolidine; and minocycline with EDTA. Quality of evidence was moderate to high in adult studies and low to moderate in pediatric studies. Use of ALT decreased the incidence of CLABSI in the majority of studies; however, there were significant differences in definitions of CVC-related infection, dwell times and lock solutions. Lock therapy may be an adjunct in high-risk cancer patients for the prevention of CLABSI; higher quality evidence is needed for specific ALT recommendations. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

In Vitro Assessment of the Antimicrobial Efficacy of Optimized Nitroglycerin-Citrate-Ethanol as a Nonantibiotic, Antimicrobial Catheter Lock Solution for Prevention of Central Line-Associated Bloodstream Infections

PubMed Central

Reitzel, Ruth A.; Hirsh-Ginsberg, Cheryl; Murray, Kimberly; Chaftari, Anne-Marie; Hachem, Ray; Raad, Issam

2016-01-01

The rapid, broad-spectrum, biofilm-eradicating activity of the combination of 0.01% nitroglycerin, 7% citrate, and 20% ethanol and its potential as a nonantibiotic, antimicrobial catheter lock solution (ACLS) were previously reported. Here, a nitroglycerin-citrate-ethanol (NiCE) ACLS optimized for clinical assessment was developed by reducing the nitroglycerin and citrate concentrations and increasing the ethanol concentration. Biofilm-eradicating activity was sustained when the ethanol concentration was increased from 20 to 22% which fully compensated for reducing the citrate concentration from 7% to 4% as well as the nitroglycerin concentration from 0.01% to 0.0015% or 0.003%. The optimized formulations demonstrated complete and rapid (2 h) eradication of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-intermediate Staphylococcus aureus (VISA), methicillin-resistant Staphylococcus epidermidis (MRSE), vancomycin-resistant enterococci (VRE), multidrug-resistant (MDR) Pseudomonas aeruginosa, MDR Klebsiella pneumoniae, MDR Enterobacter cloacae, MDR Acinetobacter baumannii, MDR Escherichia coli, MDR Stenotrophomonas maltophilia, Candida albicans, and Candida glabrata biofilms. The optimized NiCE lock solutions demonstrated anticoagulant activities comparable to those of heparin lock solutions. NiCE lock solution was significantly more effective than taurolidine-citrate-heparin lock solution in eradicating biofilms of Staphylococcus aureus and Candida glabrata. The optimized, nonantibiotic, heparin-free NiCE lock solution demonstrates rapid broad-spectrum biofilm eradication as well as effective anticoagulant activity, making NiCE a high-quality ACLS candidate for clinical assessment. PMID:27297475

Moxifloxacin superior to cefuroxime in reducing bacterial adhesion of Staphylococcus epidermidis on hydrophobic intraocular lenses.

PubMed

Benbouzid, Fathalah; Kodjikian, Laurent; Hartmann, Daniel; Renaud, François; Baillif, Stéphanie

2016-02-01

To compare the anti-adhesive effect of cefuroxime and moxifloxacin on the primary attachment phase of Staphylococcus epidermidis on hydrophobic acrylic intraocular lenses (IOLs). Forty hydrophobic acrylic IOLs were used. Two groups of IOLs were soaked in a moxifloxacin (Mox-T1: 0.5 mg/0.1 ml) or a cefuroxime (Cef-T1: cefuroxime 1 mg/0.1 ml) solution before incubation in a S. epidermidis bacterial suspension. Two other groups were incubated in the bacterial suspension before antibiotics (Cef-T2 and Mox-T2) were added. The control group (Ctrl) consisted of IOLs incubated in the bacterial suspension. After incubation, IOLs were sonicated and vortexed. The resultant suspension was spread over a nutritive agar plate. Bacterial colonies were counted after 24 hr of incubation. Mean number of colony-forming units per IOL was Cef-T1: 184 × 10(3) (SE: 5.24; SD: 28.21), Cef-T2: 117 × 10(3) (SE: 5.74; SD: 30.37), Mox-T1: 1.27 × 10(3) (SE: 0.12; SD: 0.61), Mox-T2: 25 × 10(3) (SE:1.98; SD: 9.72) and Ctrl: 361 × 10(3) (SE: 26.9; SD: 107.6). The number of adhering bacteria did not vary whether cefuroxime was added before or after IOL incubation in the bacterial suspension (p = 0.132). Moxifloxacin was more effective in reducing the number of adhering bacteria when used before IOL incubation (p < 0.001). Overall for T1 and T2, moxifloxacin was more effective than cefuroxime in reducing bacterial adhesion on IOLs (p < 0.001). Moxifloxacin and cefuroxime significantly reduced S. epidermidis adhesion on hydrophobic acrylic IOLs. The anti-adhesive effect was superior with moxifloxacin. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Hydrogen sulfide triggers late-phase preconditioning in postischemic small intestine by an NO- and p38 MAPK-dependent mechanism

PubMed Central

Yusof, Mozow; Kamada, Kazuhiro; Kalogeris, Theodore; Gaskin, F. Spencer; Korthuis, Ronald J.

2009-01-01

Hydrogen sulfide (H2S) is one of three endogenous gases, along with carbon monoxide (CO) and nitric oxide (NO), that exert a variety of important vascular actions in vivo. Although it has been demonstrated that CO or NO can trigger the development of a preconditioned phenotype in postischemic tissues, it is unclear whether H2S may also induce protection in organs subsequently exposed to ischemia-reperfusion (I/R). In light of these observations, we postulated that preconditioning with the exogenous H2S donor sodium hydrosulfide (NaHS-PC) would inhibit leukocyte rolling (LR) and adhesion (LA) induced by I/R. We used intravital microscopic techniques to demonstrate that NaHS-PC 24 h, but not 1 h, before I/R causes postcapillary venules to shift to an anti-inflammatory phenotype in wild-type (WT) mice such that these vessels fail to support LR and LA during reperfusion. The protective effect of NaHS-PC on LR was largely abolished by coincident pharmacological inhibition of NO synthase (NOS) in WT animals and was absent in endothelial NOS-deficient (eNOS−/−) mice. A similar pattern of response was noted in WT mice treated concomitantly with NaHS plus p38 mitogen-activated protein kinase (MAPK) inhibitors (SB 203580 or SK-86002). Whereas the reduction in LA induced by antecedent NaHS was attenuated by pharmacological inhibition of NOS or p38 MAPK in WT mice, the antiadhesive effect of NaHS was still evident in eNOS−/− mice. Thus NaHS-PC prevents LR and LA by triggering the activation of an eNOS- and p38 MAPK-dependent mechanism. However, the role of eNOS in the antiadhesive effect of NaHS-PC was less prominent than its effect to reduce LR. PMID:19168723

In Vivo Consumption of Cranberry Exerts ex Vivo Antiadhesive Activity against FimH-Dominated Uropathogenic Escherichia coli: A Combined in Vivo, ex Vivo, and in Vitro Study of an Extract from Vaccinium macrocarpon.

PubMed

Rafsanjany, Nasli; Senker, Jandirk; Brandt, Simone; Dobrindt, Ulrich; Hensel, Andreas

2015-10-14

For investigation of the molecular interaction of cranberry extract with adhesins of uropathogenic Escherichia coli (UPEC), urine from four volunteers consuming standardized cranberry extract (proanthocyanidin content = 1.24%) was analyzed within ex vivo experiments, indicating time-dependent significant inhibition of 40-50% of bacterial adhesion of UPEC strain NU14 to human T24 bladder cells. Under in vitro conditions a dose-dependent increase in bacterial adhesion was observed with proanthocyanidin-enriched cranberry Vaccinium macrocarpon extract (proanthocyanidin content = 21%). Confocal laser scanning microscopy and scanning electron microscopy proved that V.m. extract led to the formation of bacterial clusters on the outer plasma membrane of the host cells without subsequent internalization. This agglomerating activity was not observed when a PAC-depleted extract (V.m. extract(≠PAC)) was used, which showed significant inhibition of bacterial adhesion in cases where type 1 fimbriae dominated and mannose-sensitive UPEC strain NU14 was used. V.m. extract(≠PAC) had no inhibitory activity against P- and F1C-fimbriae dominated strain 2980. Quantitative gene expression analysis indicated that PAC-containing as well as PAC-depleted cranberry extracts increased the fimH expression in NU14 as part of a feedback mechanism after blocking FimH. For strain 2980 the PAC-containing extract led to up-regulation of P- and F1C-fimbriae, whereas the PAC-depleted extract had no influence on gene expression. V.m. and V.m. extract(≠PAC) did not influence biofilm and curli formation in UPEC strains NU14 and 2980. These data lead to the conclusion that also proanthocyanidin-free cranberry extracts exert antiadhesive activity by interaction with mannose-sensitive type 1 fimbriae of UPEC.

Marine bacteria from Danish coastal waters show antifouling activity against the marine fouling bacterium Pseudoalteromonas sp. strain S91 and zoospores of the green alga Ulva australis independent of bacteriocidal activity.

PubMed

Bernbom, Nete; Ng, Yoke Yin; Kjelleberg, Staffan; Harder, Tilmann; Gram, Lone

2011-12-01

The aims of this study were to determine if marine bacteria from Danish coastal waters produce antifouling compounds and if antifouling bacteria could be ascribed to specific niches or seasons. We further assess if antibacterial effect is a good proxy for antifouling activity. We isolated 110 bacteria with anti-Vibrio activity from different sample types and locations during a 1-year sampling from Danish coastal waters. The strains were identified as Pseudoalteromonas, Phaeobacter, and Vibrionaceae based on phenotypic tests and partial 16S rRNA gene sequence similarity. The numbers of bioactive bacteria were significantly higher in warmer than in colder months. While some species were isolated at all sampling locations, others were niche specific. We repeatedly isolated Phaeobacter gallaeciensis at surfaces from one site and Pseudoalteromonas tunicata at two others. Twenty-two strains, representing the major taxonomic groups, different seasons, and isolation strategies, were tested for antiadhesive effect against the marine biofilm-forming bacterium Pseudoalteromonas sp. strain S91 and zoospores of the green alga Ulva australis. The antiadhesive effects were assessed by quantifying the number of strain S91 or Ulva spores attaching to a preformed biofilm of each of the 22 strains. The strongest antifouling activity was found in Pseudoalteromonas strains. Biofilms of Pseudoalteromonas piscicida, Pseudoalteromonas tunicata, and Pseudoalteromonas ulvae prevented Pseudoalteromonas S91 from attaching to steel surfaces. P. piscicida killed S91 bacteria in the suspension cultures, whereas P. tunicata and P. ulvae did not; however, they did prevent adhesion by nonbactericidal mechanism(s). Seven Pseudoalteromonas species, including P. piscicida and P. tunicata, reduced the number of settling Ulva zoospores to less than 10% of the number settling on control surfaces. The antifouling alpP gene was detected only in P. tunicata strains (with purple and yellow pigmentation), so other compounds/mechanisms must be present in the other Pseudoalteromonas strains with antifouling activity.

Marine Bacteria from Danish Coastal Waters Show Antifouling Activity against the Marine Fouling Bacterium Pseudoalteromonas sp. Strain S91 and Zoospores of the Green Alga Ulva australis Independent of Bacteriocidal Activity▿†

PubMed Central

Bernbom, Nete; Ng, Yoke Yin; Kjelleberg, Staffan; Harder, Tilmann; Gram, Lone

2011-01-01

The aims of this study were to determine if marine bacteria from Danish coastal waters produce antifouling compounds and if antifouling bacteria could be ascribed to specific niches or seasons. We further assess if antibacterial effect is a good proxy for antifouling activity. We isolated 110 bacteria with anti-Vibrio activity from different sample types and locations during a 1-year sampling from Danish coastal waters. The strains were identified as Pseudoalteromonas, Phaeobacter, and Vibrionaceae based on phenotypic tests and partial 16S rRNA gene sequence similarity. The numbers of bioactive bacteria were significantly higher in warmer than in colder months. While some species were isolated at all sampling locations, others were niche specific. We repeatedly isolated Phaeobacter gallaeciensis at surfaces from one site and Pseudoalteromonas tunicata at two others. Twenty-two strains, representing the major taxonomic groups, different seasons, and isolation strategies, were tested for antiadhesive effect against the marine biofilm-forming bacterium Pseudoalteromonas sp. strain S91 and zoospores of the green alga Ulva australis. The antiadhesive effects were assessed by quantifying the number of strain S91 or Ulva spores attaching to a preformed biofilm of each of the 22 strains. The strongest antifouling activity was found in Pseudoalteromonas strains. Biofilms of Pseudoalteromonas piscicida, Pseudoalteromonas tunicata, and Pseudoalteromonas ulvae prevented Pseudoalteromonas S91 from attaching to steel surfaces. P. piscicida killed S91 bacteria in the suspension cultures, whereas P. tunicata and P. ulvae did not; however, they did prevent adhesion by nonbactericidal mechanism(s). Seven Pseudoalteromonas species, including P. piscicida and P. tunicata, reduced the number of settling Ulva zoospores to less than 10% of the number settling on control surfaces. The antifouling alpP gene was detected only in P. tunicata strains (with purple and yellow pigmentation), so other compounds/mechanisms must be present in the other Pseudoalteromonas strains with antifouling activity. PMID:22003011

[Hybrid repair of postoperative ventral hernia].

PubMed

Gogiya, B Sh; Alyautdinov, R R; Karmazanovsky, G G; Chekmareva, I A; Kopyltsov, A A

2018-01-01

To develop new technique of abdominal wall repair for postoperative ventral hernia without disadvantages which are intrinsic for open and laparoscopic surgery. Combined open and laparoscopic hernia repair was used in 18 patients with postoperative ventral hernia. Open stage provided safe dissection of abdominal adhesions and defect closure by autoplasty, laparoscopic procedure consisted of prosthesis deployment without separation of abdominal wall layers. Two types of composite endoprostheses with anti-adhesive coating were used for abdominal wall repair. There were no cases of recurrence or infectious complications in long-term period (from 3 to 106 months). Hybrid repair of postoperative ventral hernia is safe and effective procedure. Further studies are necessary to assess cost-effectiveness ratio of this method in view of expensive composite endoprostheses and laparoscopic supplies.

Aptamer Technology: Adjunct Therapy for Malaria

PubMed Central

Nik Kamarudin, Nik Abdul Aziz; Mohammed, Nurul Adila; Mustaffa, Khairul Mohd Fadzli

2017-01-01

Malaria is a life-threatening parasitic infection occurring in the endemic areas, primarily in children under the age of five, pregnant women, and patients with human immunodeficiency virus and acquired immunodeficiency syndrome (HIV)/(AIDS) as well as non-immune individuals. The cytoadherence of infected erythrocytes (IEs) to the host endothelial surface receptor is a known factor that contributes to the increased prevalence of severe malaria cases due to the accumulation of IEs, mainly in the brain and other vital organs. Therefore, further study is needed to discover a new potential anti-adhesive drug to treat severe malaria thus reducing its mortality rate. In this review, we discuss how the aptamer technology could be applied in the development of a new adjunct therapy for current malaria treatment. PMID:28536344

Binding of high molecular weight kininogen to human endothelial cells is mediated via a site within domains 2 and 3 of the urokinase receptor.

PubMed Central

Colman, R W; Pixley, R A; Najamunnisa, S; Yan, W; Wang, J; Mazar, A; McCrae, K R

1997-01-01

The urokinase receptor (uPAR) binds urokinase-type plasminogen activator (u-PA) through specific interactions with uPAR domain 1, and vitronectin through interactions with a site within uPAR domains 2 and 3. These interactions promote the expression of cell surface plasminogen activator activity and cellular adhesion to vitronectin, respectively. High molecular weight kininogen (HK) also stimulates the expression of cell surface plasminogen activator activity through its ability to serve as an acquired receptor for prekallikrein, which, after its activation, may directly activate prourokinase. Here, we report that binding of the cleaved form of HK (HKa) to human umbilical vein endothelial cells (HUVEC) is mediated through zinc-dependent interactions with uPAR. These occur through a site within uPAR domains 2 and 3, since the binding of 125I-HKa to HUVEC is inhibited by vitronectin, anti-uPAR domain 2 and 3 antibodies and soluble, recombinant uPAR (suPAR), but not by antibody 7E3, which recognizes the beta chain of the endothelial cell vitronectin receptor (integrin alphavbeta3), or fibrinogen, another alphavbeta3 ligand. We also demonstrate the formation of a zinc-dependent complex between suPAR and HKa. Interactions of HKa with endothelial cell uPAR may underlie its ability to promote kallikrein-dependent cell surface plasmin generation, and also explain, in part, its antiadhesive properties. PMID:9294114

Promoting peripheral nerve regeneration with biodegradable poly (DL-lactic acid) films

PubMed Central

Li, Ruijun; Chen, Lei; Fu, Jinling; Liu, Zhigang; Wang, Shuang; Pan, Yuehai

2015-01-01

Regeneration and repair of peripheral nerve injury has always been a major problem in the clinic. The conventional technique based on suturing the nerve ends to each other coupled with the implantation of nerve conduits outside is associated with postoperative adhesions and scar problems. Recently, a novel biodegradable poly (DL-lactic acid) (PDLLA) film has been introduced. This novel anti-adhesion film has a porous structure with better mechanical properties, better flexibility, and more controllable degradation as compared to traditional non-porous nerve conduits. However, little is known about the effects of such PDLLA films on regeneration and repair of peripheral nerve injury in vivo. In this study, we evaluated the effects of PDLLA films implantation after sciatic nerve transection and anastomosis on subsequent sciatic nerve regeneration in vivo, using a rat sciatic nerve injury model. Sciatic nerve transection surgery coupled with direct suturing only, suturing and wrapping with traditional nerve conduits, or suturing and wrapping with PDLLA films was performed on adult Wistar rats. The additional wrapping with PDLLA films inhibited the nerve adhesion after 12 weeks recovery from surgery. It also increased the compound muscle action potentials and tibialis and gastrocnemius muscle wet weight ratio following 8 weeks recovery from surgery. Regenerated nerve fibers were relatively straight and the aligned structure was complete in rats with implantations of PDLLA films. The results suggested that PDLLA films can improve the nutritional status in the muscles innervated by the damaged nerves and promote nerve regeneration in vivo. PMID:26339372

Inhibition of herpes simplex type 1 and type 2 infections by Oximacro(®), a cranberry extract with a high content of A-type proanthocyanidins (PACs-A).

PubMed

Terlizzi, Maria Elena; Occhipinti, Andrea; Luganini, Anna; Maffei, Massimo E; Gribaudo, Giorgio

2016-08-01

In the absence of efficient preventive vaccines, topical microbicides offer an attractive alternative in the prevention of Herpes simplex type 1 (HSV-1) and type 2 (HSV-2) infections. Because of their recognized anti-adhesive activity against bacterial pathogens, cranberry (Vaccinium macrocarpon Ait.) extracts may represent a natural source of new antiviral microbicides. However, few studies have addressed the applications of cranberry extract as a direct-acting antiviral agent. Here, we report on the ability of the novel cranberry extract Oximacro(®) and its purified A-type proanthocyanidins (PACs-A), to inhibit HSV-1 and HSV-2 replication in vitro. Analysis of the mode of action revealed that Oximacro(®) prevents adsorption of HSV-1 and HSV-2 to target cells. Further mechanistic studies confirmed that Oximacro(®) and its PACs-A target the viral envelope glycoproteins gD and gB, thus resulting in the loss of infectivity of HSV particles. Moreover, Oximacro(®) completely retained its anti-HSV activity even at acidic pHs (3.0 and 4.0) and in the presence of 10% human serum proteins; conditions that mimic the physiological properties of the vagina - a potential therapeutic location for Oximacro(®). Taken together, these findings indicate Oximacro(®) as an attractive candidate for the development of novel microbicides of natural origin for the prevention of HSV infections. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

The fibrinolytic mechanism of defibrotide: effect of defibrotide on plasmin activity.

PubMed

Echart, Cinara L; Graziadio, Barbara; Somaini, Simona; Ferro, Laura I; Richardson, Paul G; Fareed, Jawed; Iacobelli, Massimo

2009-12-01

Fibrinolytic activity has been shown to be reduced in many vascular diseases, including hepatic veno-occlusive disease after stem cell transplantation, a microangiopathy characterized by sinusoidal endothelial cell injury. Defibrotide is a polydisperse oligonucleotide with antithrombotic, profibrinolytic, anti-ischemic, and antiadhesive properties. Numerous clinical studies have shown promising activity of defibrotide in the treatment and prevention of veno-occlusive disease, with minimal toxicity. In corollary laboratory studies, defibrotide has been shown to decrease plasminogen activator inhibitor-1, increase tissue plasminogen activator levels, and increase overall plasma fibrinolytic activity in patients. Plasmin, a potent and nonspecific serine protease, plays a pivotal role in fibrinolysis by virtue of its ability to effectively degrade fibrin clots. In this study, defibrotide increases the activity of plasmin in hydrolyzing its substrate in a dose-dependent and length-dependent manner. Similar concentration-dependent effects of defibrotide were observed when plasmin was generated by tissue plasminogen activator or urokinase activation of plasminogen. In contrast, defibrotide had no direct effect on the activation of plasminogen to plasmin. Defibrotide was also able to enhance the activity of plasmin in degrading fibrin clot formed from fibrinogen, plasminogen, and thrombin. This effect was also concentration-dependent and directly correlated with the enzymatic activity of plasmin. This study therefore demonstrates that defibrotide is capable of enhancing the activity of plasmin and so contributes to its fibrinolytic activity. Taken together, these results support the effect of defibrotide in restoring the fibrinolytic vascular phenotype, in microangiopathic conditions such as veno-occlusive disease.

Acellular derivatives of mesenchymal stem cells prevent peritoneal adhesions in an animal model.

PubMed

Rojo, Daniel; Conget, Paulette

2018-03-01

Peritoneal adhesions are nonanatomical connections that bind organs to the abdominal wall or among them. They arise after peritoneal injury, which triggers an inflammatory response followed by a healing process that leads to fibrotic tissue formation. Mesenchymal stem cells and their secretion products, also referred to as acellular derivatives (ACDs), have anti-inflammatory, fibrinolytic, and antifibrogenic properties. The aim of this study was to determine the effect of intraoperative administration of ACD on the appearance, severity, and progression of peritoneal adhesions, in an animal model. Cecal erosions were mechanically induced in adult mice. Before closure, the vehicle, ACD, or Seprafilm was administered. Seven days later, the presence and grade of peritoneal adhesions were assessed macroscopically. One, 3, and 7 d after intervention, molecular and cellular markers of inflammation, fibrinolysis, and fibrogenesis were evaluated both locally and systemically. ACDs avoided the appearance of clinically relevant peritoneal adhesions. The vehicle had no effect, and Seprafilm reduced them inconsistently. The antiadhesive effect of ACD was associated with an early reduction of proinflammatory cytokine (tumor necrosis factor-alpha and interferon-gamma) secretion and leukocyte (polymorphonuclears, mononuclears, and macrophages) infiltration. High levels of D-dimer, low fibrin deposits, low myofibroblasts infiltration, and less fibrosis were also observed. ACD administered at the end of abdominal surgeries prevents the formation of peritoneal adhesions due to the modulation of inflammatory, fibrinolytic, and fibrogenic processes. Copyright © 2017 Elsevier Inc. All rights reserved.

Podocyte cytoskeleton is connected to the integral membrane protein podocalyxin through Na+/H+-exchanger regulatory factor 2 and ezrin.

PubMed

Takeda, Tetsuro

2003-12-01

During development, glomerular visceral epithelial cells, or podocytes, undergo extensive morphologic changes necessary for the creation of the glomerular filter. These changes include formation of interdigitating foot processes, replacement of tight junctions with slit diaphragms, and the concomitant opening of filtration slits. It was postulated previously and confirmed recently that podocalyxin, a sialomucin, plays a major role in keeping the urinary space open by virtue of the physicochemical properties of its highly negatively charged ectodomain. By a cell aggregation assay, the expression level of podocalyxin correlated closely with the anti-adhesion effect. Treatment of the cells with sialidase reversed the inhibitory effect of podocalyxin, indicating that sialic acid residue is required for inhibition of cell adhesion. In addition to its ectodomain, the highly conserved cytoplasmic tail of podocalyxin may contribute to the unique organization of podocytes. By immunocytochemistry, it was shown that two cytosolic adaptor proteins, Na(+)/H(+)-exchanger regulatory factor 2 (NHERF2) and ezrin, colocalize with podocalyxin along the apical plasma membrane of podocytes, where they form a co-immunoprecipitable complex. Moreover, the podocalyxin/NHERF2 /ezrin complex interacts with the actin cytoskeleton, and this interaction is disrupted in pathologic conditions associated with changes in the foot processes, indicating its importance in maintaining the unique organization of this epithelium. Further studies will be needed to identify the signaling molecules responsible for the regulation of this complex in podocyte damage.

A novel high-throughput assay to quantify the vaccine-induced inhibition of Bordetella pertussis adhesion to airway epithelia.

PubMed

Zanaboni, Elisa; Arato, Vanessa; Pizza, Mariagrazia; Seubert, Anja; Leuzzi, Rosanna

2016-09-15

Pertussis or whooping cough is an acute respiratory illness caused by the Gram-negative pathogen Bordetella pertussis. Despite high vaccination coverage whooping cough is currently re-emerging in many developed countries. Although the causes of pertussis resurgence are matter of debate, emerging evidences suggest that acellular vaccines efficiently protect against the hallmark symptoms of pertussis disease but fail to prevent colonization. This presumably impacts on increased risk of bacterial transmission and consequent spread throughout the population. These evidences suggest that improved vaccines may be required for efficient bacterial clearance in the upper respiratory tract. Consequently, there is a need for novel bioassays to evaluate at pre-clinical or clinical level the impact of different vaccines on B. pertussis colonization. We developed a high-throughput bacterial adhesion inhibition (BAI) assay based on human respiratory cell lines and on live bacteria chemically conjugated to a fluorescent dye. Employing A549 cells as model, we evaluated the impact of antibodies elicited by acellular (aP) and whole cell (wP) vaccines on B. pertussis adhesion in vitro. Moreover, we settled the method also on polarized Calu-3 cells grown at air-liquid interface (ALI), showing that this assay can be extended to more complex cell models mimicking the airway epithelium. We proved that this method is a sensitive, rapid and reproducible system to evaluate the anti-adhesive properties of vaccine-induced antibodies and can be employed to assess improved pertussis vaccines.

In Vitro Assessment of the Antimicrobial Efficacy of Optimized Nitroglycerin-Citrate-Ethanol as a Nonantibiotic, Antimicrobial Catheter Lock Solution for Prevention of Central Line-Associated Bloodstream Infections.

PubMed

Reitzel, Ruth A; Rosenblatt, Joel; Hirsh-Ginsberg, Cheryl; Murray, Kimberly; Chaftari, Anne-Marie; Hachem, Ray; Raad, Issam

2016-09-01

The rapid, broad-spectrum, biofilm-eradicating activity of the combination of 0.01% nitroglycerin, 7% citrate, and 20% ethanol and its potential as a nonantibiotic, antimicrobial catheter lock solution (ACLS) were previously reported. Here, a nitroglycerin-citrate-ethanol (NiCE) ACLS optimized for clinical assessment was developed by reducing the nitroglycerin and citrate concentrations and increasing the ethanol concentration. Biofilm-eradicating activity was sustained when the ethanol concentration was increased from 20 to 22% which fully compensated for reducing the citrate concentration from 7% to 4% as well as the nitroglycerin concentration from 0.01% to 0.0015% or 0.003%. The optimized formulations demonstrated complete and rapid (2 h) eradication of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-intermediate Staphylococcus aureus (VISA), methicillin-resistant Staphylococcus epidermidis (MRSE), vancomycin-resistant enterococci (VRE), multidrug-resistant (MDR) Pseudomonas aeruginosa, MDR Klebsiella pneumoniae, MDR Enterobacter cloacae, MDR Acinetobacter baumannii, MDR Escherichia coli, MDR Stenotrophomonas maltophilia, Candida albicans, and Candida glabrata biofilms. The optimized NiCE lock solutions demonstrated anticoagulant activities comparable to those of heparin lock solutions. NiCE lock solution was significantly more effective than taurolidine-citrate-heparin lock solution in eradicating biofilms of Staphylococcus aureus and Candida glabrata The optimized, nonantibiotic, heparin-free NiCE lock solution demonstrates rapid broad-spectrum biofilm eradication as well as effective anticoagulant activity, making NiCE a high-quality ACLS candidate for clinical assessment. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Antifungal activity of ionic liquids based on (-)-menthol: a mechanism study.

PubMed

Suchodolski, Jakub; Feder-Kubis, Joanna; Krasowska, Anna

2017-04-01

The mechanism of toxicity of chiral ionic liquids with (1R,2S,5R)-(-)-menthol [C n -Am-Men][Cl] (n=10, 11 or 12) in the fungus Candida albicans is reported here. Ionic liquids were more toxic towards Candida strain lacking all identified multidrug resistance efflux pumps. Moreover, the compounds tested inhibited C. albicans filamentation at the concentration at which detached fungal cells also adhered to the plastic surface. Our results showed the high activity of all the tested chiral ionic liquids in the permeabilization of C. albicans' membranes and in the digestion and interruption of the cell wall. The investigated ionic liquids thus have potential as disinfectants because besides their antifungal and antiadhesive action these compounds do not cause hemolysis. Copyright © 2017 Elsevier GmbH. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hopmann, Ch.; Weber, M.; Schöngart, M.

Micro structured optical plastics components are intensively used i. e. in consumer electronics, for optical sensors in metrology, innovative LED-lighting or laser technology. Injection moulding has proven to be successful for the large-scale production of those parts. However, the production of those parts still causes difficulties due to challenges in the moulding and demoulding of plastics parts created with laser structured mould inserts. A complete moulding of the structures often leads to increased demoulding forces, which then cause a breaking of the structures and a clogging of the mould. An innovative approach is to combine PVD-coated (physical vapour deposition), lasermore » structured inserts and a variothermal moulding process to create functional mic8iüro structures in a one-step process. Therefore, a PVD-coating is applied after the laser structuring process in order to improve the wear resistance and the anti-adhesive properties against the plastics melt. In a series of moulding trials with polycarbonate (PC) and polymethylmethacrylate (PMMA) using different coated moulds, the mould temperature during injection was varied in the range of the glass transition and the melt temperature of the polymers. Subsequently, the surface topography of the moulded parts is evaluated by digital 3D laser-scanning microscopy. The influence of the moulding parameters and the coating of the mould insert on the moulding accuracy and the demoulding behaviour are being analysed. It is shown that micro structures created by ultra-short pulse laser ablation can be successfully replicated in a variothermal moulding process. Due to the mould coating, significant improvements could be achieved in producing micro structured optical plastics components.« less

Mechanism for rapid passive-dynamic prey capture in a pitcher plant.

PubMed

Bauer, Ulrike; Paulin, Marion; Robert, Daniel; Sutton, Gregory P

2015-10-27

Plants use rapid movements to disperse seed, spores, or pollen and catch animal prey. Most rapid-release mechanisms only work once and, if repeatable, regaining the prerelease state is a slow and costly process. We present an encompassing mechanism for a rapid, repeatable, passive-dynamic motion used by a carnivorous pitcher plant to catch prey. Nepenthes gracilis uses the impact of rain drops to catapult insects from the underside of the canopy-like pitcher lid into the fluid-filled trap below. High-speed video and laser vibrometry revealed that the lid acts as a torsional spring system, driven by rain drops. During the initial downstroke, the tip of the lid reached peak velocities similar to fast animal motions and an order of magnitude faster than the snap traps of Venus flytraps and catapulting tentacles of the sundew Drosera glanduligera. In contrast to these active movements, the N. gracilis lid oscillation requires neither mechanical preloading nor metabolic energy, and its repeatability is only limited by the intensity and duration of rainfall. The underside of the lid is coated with friction-reducing wax crystals, making insects more vulnerable to perturbations. We show that the trapping success of N. gracilis relies on the combination of material stiffness adapted for momentum transfer and the antiadhesive properties of the wax crystal surface. The impact-driven oscillation of the N. gracilis lid represents a new kind of rapid plant movement with adaptive function. Our findings establish the existence of a continuum between active and passive trapping mechanisms in carnivorous plants.

Mechanism for rapid passive-dynamic prey capture in a pitcher plant

PubMed Central

Bauer, Ulrike; Paulin, Marion; Robert, Daniel; Sutton, Gregory P.

2015-01-01

Plants use rapid movements to disperse seed, spores, or pollen and catch animal prey. Most rapid-release mechanisms only work once and, if repeatable, regaining the prerelease state is a slow and costly process. We present an encompassing mechanism for a rapid, repeatable, passive-dynamic motion used by a carnivorous pitcher plant to catch prey. Nepenthes gracilis uses the impact of rain drops to catapult insects from the underside of the canopy-like pitcher lid into the fluid-filled trap below. High-speed video and laser vibrometry revealed that the lid acts as a torsional spring system, driven by rain drops. During the initial downstroke, the tip of the lid reached peak velocities similar to fast animal motions and an order of magnitude faster than the snap traps of Venus flytraps and catapulting tentacles of the sundew Drosera glanduligera. In contrast to these active movements, the N. gracilis lid oscillation requires neither mechanical preloading nor metabolic energy, and its repeatability is only limited by the intensity and duration of rainfall. The underside of the lid is coated with friction-reducing wax crystals, making insects more vulnerable to perturbations. We show that the trapping success of N. gracilis relies on the combination of material stiffness adapted for momentum transfer and the antiadhesive properties of the wax crystal surface. The impact-driven oscillation of the N. gracilis lid represents a new kind of rapid plant movement with adaptive function. Our findings establish the existence of a continuum between active and passive trapping mechanisms in carnivorous plants. PMID:26438874

The Fucosylation Inhibitor, 2-Fluorofucose, Inhibits Vaso-Occlusion, Leukocyte-Endothelium Interactions and NF-ĸB Activation in Transgenic Sickle Mice

PubMed Central

Belcher, John D.; Chen, Chunsheng; Nguyen, Julia; Abdulla, Fuad; Nguyen, Phong; Nguyen, Minh; Okeley, Nicole M.; Benjamin, Dennis R.; Senter, Peter D.; Vercellotti, Gregory M.

2015-01-01

2-Fluorofucose (2FF) blocks the fucosylation and the tethering of sialyl-Lewisx tetrasaccharide and structural variants on leukocytes and red blood cells to P- and E-selectins on activated endothelial cell surfaces. Because P- and E-selectin are required for vaso-occlusion in murine sickle cell disease (SCD), we investigated whether 2FF would inhibit vaso-occlusion in SCD mice. Microvascular stasis was measured in subcutaneous venules in NY1DD and HbSS-Townes SCD mice with dorsal skin-fold chambers after infusion of hemoglobin or exposure to hypoxia/reoxygenation. 2FF in drinking water or administered by gavage inhibited stasis in sickle mice in a dose-responsive manner. Significant inhibitory effects on stasis were seen 1 day post-treatment. 2FF treatment of SCD mice also significantly reduced leukocyte rolling and adhesion along the vessel walls of SCD mice and the static adhesion of neutrophils and sickle red blood cells isolated from 2FF-treated SCD mice to resting and activated endothelial cells. Total white blood cell counts increased in response to 2FF. NF-ĸB activation and VCAM-1 and E-selectin expression were inhibited in the livers of SCD mice consistent with an overall decrease in vascular inflammation and ischemia-reperfusion physiology. Pretreatment with 2FF completely eliminated heme-induced lethality in HbSS-Townes mice, consistent with the observed anti-inflammatory and anti-adhesive properties of 2FF in SCD mice. These data suggest that 2FF may be beneficial for preventing or treating vaso-occlusive crises in SCD patients. PMID:25706118

Green synthesis of Kocuran-functionalized silver glyconanoparticles for use as antibiofilm coatings on silicone urethral catheters

NASA Astrophysics Data System (ADS)

Ganesh Kumar, C.; Sujitha, Pombala

2014-08-01

Microbial infections due to biofilm formation on medical implants are serious complications arising after surgery which can be prevented by using antimicrobial coatings on biomaterial surfaces. We developed a simple, rapid and green chemistry approach for synthesis of silver glyconanoparticles (AgNPs) using Kocuran, an exopolysaccharide produced by Kocuria rosea strain BS-1. Kocuran-capped AgNPs exhibited a characteristic surface plasmon resonance (SPR) peak around 435 nm. They were mono-dispersed, spherical with an average particle size of 12 nm. XRD and SAED studies suggested that AgNPs were crystalline in nature. AgNPs had a zeta potential of -33.9 mV and were anionic charged. They showed colloidal stability at different pH (6 to 10), temperatures (30 °C to 100 °C), in NaCl, NaNO3 and BSA solutions. Kocuran-capped AgNPs exhibited effective antimicrobial activity against Staphylococcus aureus and Escherichia coli and cell death was mainly due to hydroxyl radical induction and depletion of NADH. They also inhibited the biofilm development by S. aureus and E. coli and confocal scanning laser microscopic images revealed the damage of intact cell architecture. In vitro evaluation of Kocuran-capped silver glyconanoparticles on human gingival fibroblasts demonstrated good cell proliferation as compared to commercial AgNPs suggesting that they are biocompatible and non-toxic in nature. This is a first report on Kocuran-functionalized AgNPs exhibiting potential antibacterial and antiadhesive properties for use as antimicrobial coatings against bacterial adhesion and biofilm formation on silicone urethral catheters.

Implications of Biofilm Formation on Urological Devices

NASA Astrophysics Data System (ADS)

Cadieux, Peter A.; Wignall, Geoffrey R.; Carriveau, Rupp; Denstedt, John D.

2008-09-01

Despite millions of dollars and several decades of research targeted at their prevention and eradication, biofilm-associated infections remain the major cause of urological device failure. Numerous strategies have been aimed at improving device design, biomaterial composition, surface properties and drug delivery, but have been largely circumvented by microbes and their plethora of attachment, host evasion, antimicrobial resistance, and dissemination strategies. This is not entirely surprising since natural biofilm formation has been going on for millions of years and remains a major part of microorganism survival and evolution. Thus, the fact that biofilms develop on and in the biomaterials and tissues of humans is really an extension of this natural tendency and greatly explains why they are so difficult for us to combat. Firstly, biofilm structure and composition inherently provide a protective environment for microorganisms, shielding them from the shear stress of urine flow, immune cell attack and some antimicrobials. Secondly, many biofilm organisms enter a metabolically dormant state that renders them tolerant to those antibiotics and host factors able to penetrate the biofilm matrix. Lastly, the majority of organisms that cause biofilm-associated urinary tract infections originate from our own oral cavity, skin, gastrointestinal and urogenital tracts and therefore have already adapted to many of our host defenses. Ultimately, while biofilms continue to hold an advantage with respect to recurrent infections and biomaterial usage within the urinary tract, significant progress has been made in understanding these dynamic microbial communities and novel approaches offer promise for their prevention and eradication. These include novel device designs, antimicrobials, anti-adhesive coatings, biodegradable polymers and biofilm-disrupting compounds and therapies.

Modification of the surfaces of medical devices to prevent microbial adhesion and biofilm formation.

PubMed

Desrousseaux, C; Sautou, V; Descamps, S; Traoré, O

2013-10-01

The development of devices with surfaces that have an effect against microbial adhesion or viability is a promising approach to the prevention of device-related infections. To review the strategies used to design devices with surfaces able to limit microbial adhesion and/or growth. A PubMed search of the published literature. One strategy is to design medical devices with a biocidal agent. Biocides can be incorporated into the materials or coated or covalently bonded, resulting either in release of the biocide or in contact killing without release of the biocide. The use of biocides in medical devices is debated because of the risk of bacterial resistance and potential toxicity. Another strategy is to modify the chemical or physical surface properties of the materials to prevent microbial adhesion, a complex phenomenon that also depends directly on microbial biological structure and the environment. Anti-adhesive chemical surface modifications mostly target the hydrophobicity features of the materials. Topographical modifications are focused on roughness and nanostructures, whose size and spatial organization are controlled. The most effective physical parameters to reduce bacterial adhesion remain to be determined and could depend on shape and other bacterial characteristics. A prevention strategy based on reducing microbial attachment rather than on releasing a biocide is promising. Evidence of the clinical efficacy of these surface-modified devices is lacking. Additional studies are needed to determine which physical features have the greatest potential for reducing adhesion and to assess the usefulness of antimicrobial coatings other than antibiotics. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Carbohydrate Coating Reduces Adhesion of Biofilm-Forming Bacillus subtilis to Gold Surfaces

PubMed Central

Kesel, S.; Mader, A.; Seeberger, P. H.; Lieleg, O.

2014-01-01

The growth of bacterial biofilms in pipes and food tanks causes severe problems in industry. Biofilms growing on medical implants or catheters are of great concern, as they can cause serious infections and decrease the functionality of the medical device. The prevention of bacterial adhesion—the first step in colonization and biofilm formation—is therefore very important. Current research comprises alterations in surface properties, the prevention of adhesin biosynthesis, inhibition with receptor analogs, or the development of anti-adhesive vaccines. We present a new approach that allows us to study bacterial adhesion with high sensitivity in real-time while testing several different surfaces in parallel. Using the cantilever-array technique we demonstrate that coating of gold surfaces with mono- or disaccharides results in a reduction of the bacterial adhesion of the biofilm-forming bacterium Bacillus subtilis NCIB 3610 to these gold surfaces. This reduction in bacterial adhesion is independent of the studied carbohydrate. Using several mutant strains, we investigate the underlying molecular interactions, and our results suggest that adhesion to gold surfaces is mediated by thiol groups present in proteins of the bacterial cell membrane or biofilm matrix proteins expressed at low levels by the wild-type strain. Furthermore, our data indicate that the adhesion of B. subtilis NCIB 3610 to carbohydrate-coated gold surfaces is facilitated by interactions between carbohydrates installed on the cantilever gold surface and an exopolysaccharide expressed by this strain. Understanding general and specific contributions of molecular interactions mediating bacterial adhesion will enable its prevention in the future. PMID:25038098

Inhibition of metastatic potential of B16-F10 melanoma cell line in vivo and in vitro by biflorin.

PubMed

Andrade Carvalho, Adriana; da Costa, Patrícia Marçal; Da Silva Souza, Luciana Gregório; Lemos, Telma Leda G; Alves, Ana Paula Negreiros Nunes; Pessoa, Cláudia; de Moraes, Manoel Odorico

2013-08-14

The aim of this study was to determine the antimetastatic potential of biflorin using in vivo and in vitro approaches. Biflorin was isolated from Capraria biflora collected in Fortaleza, Ceará, Brazil. Adhesion, migration and invasion assays were performed to avail of the antimetastatic potential of this quinone. Experimental metastasis was performed to avail of the antimetastatic potential of bilflorin using in vivo assay. Treatment with biflorin (25 and 50mg/kg/day) was shown to be effective in reducing B16-F10 melanoma metastasis in C57BL/6 mice. The administration of biflorin at 25mg/kg/day intraperitoneally inhibited the formation of metastases by about 57% compared to untreated control animals. When the animals were treated with 50mg/kg/day intraperitoneally, there was a 71% decrease in the number of lung metastases. Morphological assays showed the presence of hemosiderin and erythrocytes in the lung parenchyma, indicating the occurrence of hemorrhage, probably a side effect of biflorin. Biflorin at non-toxic concentrations (0.5, 1.0 and 1.5g/mL) was tested directly on B16-F10 cells in vitro, and it inhibited cell adhesion to type I collagen and cell motility using the wound-healing assay. These data suggest that biflorin has a promising antimetastatic potential, as shown by its anti-adhesion, anti-migration and anti-invasion properties against a metastatic melanoma cell line. However, further studies are essential to elucidate its mechanism of action. Copyright © 2013 Elsevier Inc. All rights reserved.

Coating Reduces Ice Adhesion

NASA Technical Reports Server (NTRS)

Smith, Trent; Prince, Michael; DwWeese, Charles; Curtis, Leslie

2008-01-01

The Shuttle Ice Liberation Coating (SILC) has been developed to reduce the adhesion of ice to surfaces on the space shuttle. SILC, when coated on a surface (foam, metal, epoxy primer, polymer surfaces), will reduce the adhesion of ice by as much as 90 percent as compared to the corresponding uncoated surface. This innovation is a durable coating that can withstand several cycles of ice growth and removal without loss of anti-adhesion properties. SILC is made of a binder composed of varying weight percents of siloxane(s), ethyl alcohol, ethyl sulfate, isopropyl alcohol, and of fine-particle polytetrafluoroethylene (PTFE). The combination of these components produces a coating with significantly improved weathering characteristics over the siloxane system alone. In some cases, the coating will delay ice formation and can reduce the amount of ice formed. SILC is not an ice prevention coating, but the very high water contact angle (greater than 140 ) causes water to readily run off the surface. This coating was designed for use at temperatures near -170 F (-112 C). Ice adhesion tests performed at temperatures from -170 to 20 F (-112 to -7 C) show that SILC is a very effective ice release coating. SILC can be left as applied (opaque) or buffed off until the surface appears clear. Energy dispersive spectroscopy (EDS) and x-ray photoelectron spectroscopy (XPS) data show that the coating is still present after buffing to transparency. This means SILC can be used to prevent ice adhesion even when coating windows or other objects, or items that require transmission of optical light. Car windshields are kept cleaner and SILC effectively mitigates rain and snow under driving conditions.

Gold glyconanoparticles as new tools in antiadhesive therapy.

PubMed

Rojo, Javier; Díaz, Vicente; de la Fuente, Jesús M; Segura, Inmaculada; Barrientos, Africa G; Riese, Hans H; Bernad, Antonio; Penadés, Soledad

2004-03-05

Gold glyconanoparticles (GNPs) have been prepared as new multivalent tools that mimic glycosphingolipids on the cell surface. GNPs are highly soluble under physiological conditions, stable against enzymatic degradation and nontoxic. Thereby GNPs open up a novel promising multivalent platform for biological applications. It has recently been demonstrated that specific tumor-associated carbohydrate antigens (glycosphingolipids and glycoproteins) are involved in the initial step of tumor spreading. A mouse melanoma model was selected to test glyconanoparticles as possible inhibitors of experimental lung metastasis. A carbohydrate-carbohydrate interaction is proposed as the first recognition step for this process. Glyconanoparticles presenting lactose (lacto-GNPs) have been used successfully to significantly reduce the progression of experimental metastasis. This result shows for the first time a clear biological effect of lacto-GNPs, demonstrating the potential application of this glyconanotechnology in biological processes.

Immunotherapy in the management of sepsis.

PubMed

Sikora, Janusz Piotr

2002-01-01

This work presents the role of Gram-negative bacteria endotoxins, pro- and anti-inflammatory cytokines and reactive oxygen species (ROS) in the complex and not fully explained pathogenesis of sepsis. The so-called "respiratory burst" of neutrophils and the antioxidant mechanisms of the host are also discussed. The work focuses on possible approaches to the management of sepsis connected with immunotherapy. Neutralization of endotoxin lipopolysaccharide (LPS), anti-tumor necrosis factor alpha (TNF-alpha) therapy with monoclonal antibodies or pentoxifylline (PTXF), as well as soluble recombinant cytokine agonists and antagonists used in clinical trials are taken into consideration. In addition, cytokine manipulation therapy, anti-adhesion techniques, glucocorticoides and antioxidant barrier interference are also described. So far there has been no immunotherapy of sepsis in children of proven clinical efficacy, which prompts an aggressive examination of the immune system aimed at affecting its function.

[Skin diseases and sensitization to metals in construction workers engaged in the production of pre-cast cellular concrete slabs].

PubMed

Kieć-Swierczyńska, M; Woźniak, H; Wojtczak, J

1989-01-01

The study involved 461 building workers exposed to ashes, cement and ash-cement mixtures in direct production and at auxiliary posts (fitters, welders, mechanics, electricians etc.). In addition, all those workers were exposed to lubricants ans machine oils, as well as anti-adhesive oils used to lubricate moulds. All the subjects underwent patch tests. Dermatitis was found in 18.9%, whereas oil acne in 7.4% of subjects, 23.0% exhibited chromium allergy, 15.2% - cobalt allergy and 5.0% - nickel allergy. Two workers were ++hypersensitive to zinc. No differences were found in the rates of dermatitis, oil acne and metal allergy between production workers and auxiliary ones. Airborne dust concentrations at those workplaces were similar. Cement and ashes contained compounds of chromium, cobalt and nickel.

Update on the Medical Management of Crohn's Disease.

PubMed

Deepak, Parakkal; Bruining, David H

2015-11-01

The medical management of Crohn's disease is a rapidly evolving field with expanding therapeutic drug options and treatment strategies. In addition to corticosteroids, immunomodulators, and anti-tumor necrosis (anti-TNF) agents, a new anti-adhesion medication (vedolizumab) has been approved. Individualized patient-based dosing of immunomodulators and biologic agents is now possible with therapeutic drug monitoring (TDM). There is a changing paradigm in treatment goals to achieve deeper remission identified by composite clinical and endoscopic endpoints. More aggressive treatment strategies in the postoperative setting have been proposed due to emerging data on medication efficacy in this setting. Management algorithms that stratify CD patients into risk groups to balance treatment benefit against adverse events and costs are being developed to translate research into clinical practice. This review provides an update on these new developments for practicing gastroenterologists.

Antibacterial Applications of Nanodiamonds.

PubMed

Szunerits, Sabine; Barras, Alexandre; Boukherroub, Rabah

2016-04-12

Bacterial infectious diseases, sharing clinical characteristics such as chronic inflammation and tissue damage, pose a major threat to human health. The steady increase of multidrug-resistant bacteria infections adds up to the current problems modern healthcare is facing. The treatment of bacterial infections with multi-resistant germs is very difficult, as the development of new antimicrobial drugs is hardly catching up with the development of antibiotic resistant pathogens. These and other considerations have generated an increased interest in the development of viable alternatives to antibiotics. A promising strategy is the use of nanomaterials with antibacterial character and of nanostructures displaying anti-adhesive activity against biofilms. Glycan-modified nanodiamonds (NDs) revealed themselves to be of great promise as useful nanostructures for combating microbial infections. This review summarizes the current efforts in the synthesis of glycan-modified ND particles and evaluation of their antibacterial and anti-biofilm activities.

Biodegradable and thermosensitive monomethoxy poly(ethylene glycol)-poly(lactic acid) hydrogel as a barrier for prevention of post-operative abdominal adhesion.

PubMed

Fu, Shao Zhi; Li, Zhi; Fan, Jun Ming; Meng, Xiao Hang; Shi, Kun; Qu, Ying; Yang, Ling Lin; Wu, Jing Bo; Fan, Juan; Luot, Feng; Qian, Zhi Yong

2014-03-01

Post-operative peritoneal adhesions are serious consequences of abdominal or pelvic surgery and cause severe bowel obstruction, chronic pelvic pain and infertility. In this study, a novel nano-hydrogel system based on a monomethoxy poly(ethylene glycol)-poly(lactic acid) (MPEG-PLA) di-block copolymer was studied for its ability to prevent abdominal adhesion in rats. The MPEG-PLA hydrogel at a concentration of 40% (w/v) was injected and was able to adhere to defect sites at body temperature. The ability of the hydrogel to inhibit adhesion of post-operative tissues was evaluated by utilizing a rat model of abdominal sidewall-cecum abrasion. It was possible to heal wounded tissue through regeneration of neo-peritoneal tissues ten days after surgery. Our data showed that this hydrogel system is equally as effective as current commercialized anti-adhesive products.

Muc4/MUC4 functions and regulation in cancer.

PubMed

Carraway, Kermit L; Theodoropoulos, George; Kozloski, Goldi A; Carothers Carraway, Coralie A

2009-12-01

The membrane mucin MUC4 (human) is abundantly expressed in many epithelia, where it is proposed to play a protective role, and is overexpressed in some epithelial tumors. Studies on the rat homologue, Muc4, indicate that it acts through anti-adhesive or signaling mechanisms. In particular, Muc4/MUC4 can serve as a ligand/modulator of the receptor tyrosine kinase ErbB2, regulating its phosphorylation and the phosphorylation of its partner ErbB3, with or without the involvement of the ErbB3 ligand neuregulin. Muc4/MUC4 can also modulate cell apoptosis via multiple mechanisms, both ErbB2 dependent and independent. Muc4/MUC4 expression is regulated by multiple mechanisms, ranging from transcriptional to post-translational. The roles of MUC4 in tumors suggest that it may be valuable as a tumor marker or target for therapy.

Impact of cranberry on Escherichia coli cellular surface characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Brandy J.; Lin Baochuan; Dinderman, Michael A.

2008-12-19

The anti-adhesive effects of cranberry have been attributed to both interactions of its components with the surface of bacterial cells and to inhibition of p-fimbriae expression. Previous reports also suggested that the presence of cranberry juice changed the Gram stain characteristics of Escherichia coli. Here, we show that the morphology of E. coli is changed when grown in the presence of juice or extract from Vaccinium macrocarpon (cranberry). Gene expression analysis indicates the down regulation of flagellar basal body rod and motor proteins. Consistent with this finding and previous reports, the SEM images indicate a decrease in the visible p-fimbriae.more » The iodine used in Gram-staining protocols was found to interact differently with the bacterial membrane when cells were cultured in spiked media. Slight alterations in the Gram stain protocol demonstrated that culturing in the presence of cranberry juice does not change the Gram stain characteristics contradicting other reports.« less

Antibacterial Applications of Nanodiamonds

PubMed Central

Szunerits, Sabine; Barras, Alexandre; Boukherroub, Rabah

2016-01-01

Bacterial infectious diseases, sharing clinical characteristics such as chronic inflammation and tissue damage, pose a major threat to human health. The steady increase of multidrug-resistant bacteria infections adds up to the current problems modern healthcare is facing. The treatment of bacterial infections with multi-resistant germs is very difficult, as the development of new antimicrobial drugs is hardly catching up with the development of antibiotic resistant pathogens. These and other considerations have generated an increased interest in the development of viable alternatives to antibiotics. A promising strategy is the use of nanomaterials with antibacterial character and of nanostructures displaying anti-adhesive activity against biofilms. Glycan-modified nanodiamonds (NDs) revealed themselves to be of great promise as useful nanostructures for combating microbial infections. This review summarizes the current efforts in the synthesis of glycan-modified ND particles and evaluation of their antibacterial and anti-biofilm activities. PMID:27077871

Streptococcus faecium M 74 in control of diarrhoea induced by a human enterotoxigenic Escherichia coli strain in an infant rabbit model.

PubMed

Wadström, T

1984-08-01

Streptococcus faecium strain M 74 was evaluated as a prophylacticum for enterotoxigenic Escherichia coli (ETEC) diarrhoea with human isolates of E. coli with CFA/I and CFA/II surface fimbrial haemagglutinins (adhesins) in a rabbit model. Young rabbits (3 to 4 days old) were given S. faecium organisms (5 X 10(9)) 15 min before (group A), 6 h before (group B) and 12 h after (group C) challenge with ETEC organisms. Only 4 out of 26 rabbits in group A, 6 out of 21 in group B and 7 out of 23 in group C developed diarrhoea. In conclusion, this S. faecium strain M 74 seems efficiently to protect animals from ETEC diarrhoea when given as a prophylactic agent at a high dose. This animal model seems useful for comparative studies on new preventive methods for ETEC diarrhoea such as testing probiotics and antiadhesive drugs.

Effective new membrane for preventing postthoracotomy pleural adhesion by surface water induction technology

PubMed Central

Nakata, Mary; Goya, Seijirow; Fukayama, Toshiharu

2017-01-01

Background After thoracic surgery, adhesions between the pleura can cause substantial complications. This study investigated the effectiveness of a novel membrane utilizing surface water induction technology to prevent adhesions. Methods Eight beagles were divided into an experimental group (five males) and a control group (three females). The experimental group underwent thoracotomy on both the left and right sides of the chest. Both sides received the membrane, and the membrane on one side was glued to the pleura using tissue adhesive. The control group underwent thoracotomy only on the left side. Two weeks postoperatively, all dogs were sacrificed and adhesions were evaluated macroscopically and microscopically. Results Severe adhesion was seen between the parietal and visceral pleura in all control dogs, whereas the experimental group showed minor adhesion in only one dog on one side. Conclusions Our novel anti-adhesive membrane appeared highly effective in preventing postthoracotomy pleural adhesions. PMID:28654705

Injection moulding of optical functional micro structures using laser structured, PVD-coated mould inserts

NASA Astrophysics Data System (ADS)

Hopmann, Ch.; Weber, M.; Schöngart, M.; Schäfer, C.; Bobzin, K.; Bagcivan, N.; Brögelmann, T.; Theiß, S.; Münstermann, T.; Steger, M.

2015-05-01

Micro structured optical plastics components are intensively used i. e. in consumer electronics, for optical sensors in metrology, innovative LED-lighting or laser technology. Injection moulding has proven to be successful for the large-scale production of those parts. However, the production of those parts still causes difficulties due to challenges in the moulding and demoulding of plastics parts created with laser structured mould inserts. A complete moulding of the structures often leads to increased demoulding forces, which then cause a breaking of the structures and a clogging of the mould. An innovative approach is to combine PVD-coated (physical vapour deposition), laser structured inserts and a variothermal moulding process to create functional mic8iüro structures in a one-step process. Therefore, a PVD-coating is applied after the laser structuring process in order to improve the wear resistance and the anti-adhesive properties against the plastics melt. In a series of moulding trials with polycarbonate (PC) and polymethylmethacrylate (PMMA) using different coated moulds, the mould temperature during injection was varied in the range of the glass transition and the melt temperature of the polymers. Subsequently, the surface topography of the moulded parts is evaluated by digital 3D laser-scanning microscopy. The influence of the moulding parameters and the coating of the mould insert on the moulding accuracy and the demoulding behaviour are being analysed. It is shown that micro structures created by ultra-short pulse laser ablation can be successfully replicated in a variothermal moulding process. Due to the mould coating, significant improvements could be achieved in producing micro structured optical plastics components.

Novel properties of Hippophae rhamnoides L. twig and leaf extracts - anti-virulence action and synergy with antifungals studied in vitro on Candida spp. model.

PubMed

Sadowska, Beata; Budzyńska, Aleksandra; Stochmal, Anna; Żuchowski, Jerzy; Różalska, Barbara

2017-06-01

Original, chemically characterized Sea buckthorn (SBT) twig and leaf extracts were in vitro studied in terms of anti-Candida activity. Minimum inhibitory concentrations (MICs) of the extracts against C. albicans ATCC 10231 ranged: 250 μg/ml (twig), 31.5 μg/ml (leaf), and against C. glabrata G1 (clinical isolate) - 15.6 μg/ml (twig), 3.9 μg/ml (leaf). Next the extracts have been used at their subMIC. Both extracts significantly enhanced activity of fluconazole (FLC) and caspofungin (CAS) against C. albicans and increased their efficacy against C. glabrata, measured by an agar dilution assay combined with the E-test. The extracts inhibited C. albicans morphogenesis such as germ tube and hyphae formation as well as invasion to the "Spider" Agar. Antiadhesive and anti-biofilm activities of the extracts were evaluated by Alamar Blue reduction assay. It showed not significant reduction in the degree of cell adhesion (by 10-15%) but noticeable decrease of biofilm formation (by 80% in the case of SBT-twig extract). In conclusion, this study provided the evidence that SBT extracts, used at non-cytotoxic concentrations for the fibroblasts (IC 50 from 664.8 μg/ml to 1060.4 μg/ml), targeted some of Candida spp. virulence factors essential for the establishment of the infection. SBT twigs, previously regarded as waste material, were shown to be also a valuable source of the substances with promising antimicrobial activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization of increasing stages of invasiveness identifies stromal/cancer cell crosstalk in rat models of mesothelioma

PubMed Central

Nader, Joëlle S.; Abadie, Jérôme; Deshayes, Sophie; Boissard, Alice; Blandin, Stéphanie; Blanquart, Christophe; Boisgerault, Nicolas; Coqueret, Olivier; Guette, Catherine; Grégoire, Marc; Pouliquen, Daniel L.

2018-01-01

Sarcomatoid mesothelioma (SM) is a devastating cancer associated with one of the poorest outcome. Therefore, representative preclinical models reproducing different tumor microenvironments (TME) observed in patients would open up new prospects for the identification of markers and evaluation of innovative therapies. Histological analyses of four original models of rat SM revealed their increasing infiltrative and metastatic potential were associated with differences in Ki67 index, blood-vessel density, and T-lymphocyte and macrophage infiltration. In comparison with the noninvasive tumor M5-T2, proteomic analysis demonstrated the three invasive tumors F4-T2, F5-T1 and M5-T1 shared in common a very significant increase in the abundance of the multifunctional proteins galectin-3, prohibitin and annexin A5, and a decrease in proteins involved in cell adhesion, tumor suppression, or epithelial differentiation. The increased metastatic potential of the F5-T1 tumor, relative to F4-T2, was associated with an increased macrophage vs T-cell infiltrate, changes in the levels of expression of a panel of cytokine genes, an increased content of proteins involved in chromatin organization, ribosome structure, splicing, or presenting anti-adhesive properties, and a decreased content of proteins involved in protection against oxidative stress, normoxia and intracellular trafficking. The most invasive tumor, M5-T1, was characterized by a pattern of specific phenotypic and molecular features affecting the presentation of MHC class I-mediated antigens and immune cell infiltration, or involved in the reorganization of the cytoskeleton and composition of the extracellular matrix. These four preclinical models and data represent a new resource available to the cancer research community to catalyze further investigations on invasiveness. PMID:29662647

Effects of sevuparin on rosette formation and cytoadherence of Plasmodium falciparum infected erythrocytes

PubMed Central

Saiwaew, Somporn; Sritabal, Juntima; Piaraksa, Nattaporn; Keayarsa, Srisuda; Ruengweerayut, Ronnatrai; Utaisin, Chirapong; Sila, Patima; Niramis, Rangsan; Udomsangpetch, Rachanee; Charunwatthana, Prakaykaew; Pongponratn, Emsri; Pukrittayakamee, Sasithon; Leitgeb, Anna M.; Wahlgren, Mats; Lee, Sue J.; Day, Nicholas P. J.; White, Nicholas J.; Dondorp, Arjen M.; Chotivanich, Kesinee

2017-01-01

In severe falciparum malaria cytoadherence of parasitised red blood cells (PRBCs) to vascular endothelium (causing sequestration) and to uninfected red cells (causing rosette formation) contribute to microcirculatory flow obstruction in vital organs. Heparin can reverse the underlying ligand-receptor interactions, but may increase the bleeding risks. As a heparin-derived polysaccharide, sevuparin has been designed to retain anti-adhesive properties, while the antithrombin-binding domains have been eliminated, substantially diminishing its anticoagulant activity. Sevuparin has been evaluated recently in patients with uncomplicated falciparum malaria, and is currently investigated in a clinical trial for sickle cell disease. The effects of sevuparin on rosette formation and cytoadherence of Plasmodium falciparum isolates from Thailand were investigated. Trophozoite stages of P. falciparum-infected RBCs (Pf-iRBCs) were cultured from 49 patients with malaria. Pf-iRBCs were treated with sevuparin at 37°C and assessed in rosetting and in cytoadhesion assays with human dermal microvascular endothelial cells (HDMECs) under static and flow conditions. The proportion of Pf-iRBCs forming rosettes ranged from 6.5% to 26.0% (median = 12.2%). Rosetting was dose dependently disrupted by sevuparin (50% disruption by 250 μg/mL). Overall 57% of P. falciparum isolates bound to HDMECs under static conditions; median (interquartile range) Pf-iRBC binding was 8.5 (3.0–38.0) Pf-iRBCs/1000 HDMECs. Sevuparin in concentrations ≥ 100 μg/mL inhibited cytoadherence. Sevuparin disrupts P. falciparum rosette formation in a dose dependent manner and inhibits cytoadherence to endothelial cells. The data support assessment of sevuparin as an adjunctive treatment to the standard therapy in severe falciparum malaria. PMID:28249043

Occurrence of N-phenylpropenoyl-L-amino acid amides in different herbal drugs and their influence on human keratinocytes, on human liver cells and on adhesion of Helicobacter pylori to the human stomach.

PubMed

Hensel, A; Deters, A M; Müller, G; Stark, T; Wittschier, N; Hofmann, T

2007-02-01

Thirty commonly used medicinal plants were screened by a selective and specific LC-MS/MS method for the occurrence of N-phenylpropenoyl- L-amino acid amides, a new homologous class of secondary products. In 15 plants, one or more of the respective derivatives (1 to 12) were found and quantitated. Especially roots from Angelica archangelica, fruits of Cassia angustifolia, C. senna, Coriandrum sativum, leaves from Hedera helix, flowers from Lavandula spec. and from Sambucus nigra contained high amounts (1 to 11 microg/g) of mixtures of the different amides 1 to 12. For functional investigations on potential activity in cellular physiology, two amides with an aliphatic (8) and an aromatic amino acid residue (5) were used. N-(E)-Caffeic acid L-aspartic acid amide (8) and N-(E)-caffeic acid L-tryptophan amide (5) stimulated mitochondrial activity as well as the proliferation rate of human liver cells (HepG2) at 10 microg/mL significantly. When monitoring the influence of selected phase I and II metabolizing enzymes, both compounds did not influence CYP3A4 gene expression, but stimulated CYP1A2 gene expression and inhibited GST expression. Also, the proliferation of human keratinocytes (NHK) was increased up to 150% by both amides 5 and 8; this stimulation was also detectable on the level of gene expression by an up-regulation of the transcription factor STAT6. The aliphatic aspartic compound 8 showed strong antiadhesive properties on the adhesion of Helicobacter pylori to human stomach tissue.

Evaluation of probiotic properties of Lactobacillus plantarum WLPL04 isolated from human breast milk.

PubMed

Jiang, Meiling; Zhang, Fen; Wan, Cuixiang; Xiong, Yonghua; Shah, Nagendra P; Wei, Hua; Tao, Xueying

2016-03-01

Lactobacillus plantarum WLPL04, a specific strain isolated from human breast milk, was investigated for its survival capacity (acid and bile salt tolerance, survival in simulated gastrointestinal tract, inhibition of pathogens, antibiotic susceptibility, yield of exopolysaccharides) and probiotic properties (antiadhesion of pathogens, protection from harmful effect of sodium dodecyl sulfate, and antiinflammatory stress on Caco-2 cells). The results showed that Lb. plantarum WLPL04 had broad-spectrum activity against gram-positive strains (Listeria monocytogenes CMCC54007, Bacillus cereus ATCC14579, and Staphylococcus aureus CMCC26003) and gram-negative strains (Pseudomonas aeruginosa MCC10104, Shigella sonnei ATCC25931, Enterobacter sakazakii ATCC29544, Salmonella typhimurium ATCC13311, and Escherichia coli O157:H7). Antibiotic susceptibility tests showed that Lb. plantarum WLPL04 was susceptible to 8 of 14 antibiotics (e.g., erythromycin and nitrofurantoin) and resistant to 6 of 14 antibiotics (e.g., kanamycin and bacitracin). Lactobacillus plantarum WLPL04 was able to survive at pH 2.5 for 3h and at 0.45% bile salt for 12h, suggesting that it can survive well in the gastrointestinal tract. In addition, the exopolysaccharide yield of Lb. plantarum WLPL04 reached 426.73 ± 65.56 mg/L at 24h. With strategies of competition, inhibition, and displacement, Lb. plantarum WLPL04 reduced the adhesion of E. coli O157:H7 (35.51%), Sal. typhimurium ATCC 13311 (8.10%), and Staph. aureus CMCC 26003 (40.30%) on Caco-2 cells by competition, and subsequently by 59.80, 62.50, and 42.60%, respectively, for the 3 pathogens through inhibition, and by 75.23, 39.97, and 52.88%, respectively, through displacement. Lactobacillus plantarum WLPL04 attenuated the acute stress induced by sodium dodecyl sulfate on Caco-2 cells and significantly inhibited the expression of inflammatory cytokines (IL-6, IL-8 and tumor necrosis factor-α) on Caco-2 cells but increased IL-10 expression in vitro compared with the Salmonella-treated group. In summary, Lb. plantarum WLPL04 from breast milk could be considered as a probiotic candidate for dairy products to promote human health. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The Design of Simple Bacterial Microarrays: Development towards Immobilizing Single Living Bacteria on Predefined Micro-Sized Spots on Patterned Surfaces.

PubMed

Arnfinnsdottir, Nina Bjørk; Ottesen, Vegar; Lale, Rahmi; Sletmoen, Marit

2015-01-01

In this paper we demonstrate a procedure for preparing bacterial arrays that is fast, easy, and applicable in a standard molecular biology laboratory. Microcontact printing is used to deposit chemicals promoting bacterial adherence in predefined positions on glass surfaces coated with polymers known for their resistance to bacterial adhesion. Highly ordered arrays of immobilized bacteria were obtained using microcontact printed islands of polydopamine (PD) on glass surfaces coated with the antiadhesive polymer polyethylene glycol (PEG). On such PEG-coated glass surfaces, bacteria were attached to 97 to 100% of the PD islands, 21 to 62% of which were occupied by a single bacterium. A viability test revealed that 99% of the bacteria were alive following immobilization onto patterned surfaces. Time series imaging of bacteria on such arrays revealed that the attached bacteria both divided and expressed green fluorescent protein, both of which indicates that this method of patterning of bacteria is a suitable method for single-cell analysis.

Fermentation and dry fractionation increase bioactivity of cloudberry (Rubus chamaemorus).

PubMed

Puupponen-Pimiä, Riitta; Nohynek, Liisa; Juvonen, Riikka; Kössö, Tuija; Truchado, Pilar; Westerlund-Wikström, Benita; Leppänen, Tiina; Moilanen, Eeva; Oksman-Caldentey, Kirsi-Marja

2016-04-15

Phenolic composition and bioactivity of cloudberry was modified by bioprocessing, and highly bioactive fractions were produced by dry fractionation of the press cake. During fermentation polymeric ellagitannins were partly degraded into ellagic acid derivatives. Phenolic compounds were differentially distributed in seed coarse and fine fractions after dry fractionation process. Tannins concentrated in fine fraction, and flavonol derivatives were mainly found in coarse fraction. Ellagic acid derivatives were equally distributed between the dry fractions. Fermentation and dry fractionation increased statistically significantly anti-adhesion and anti-inflammatory activity of cloudberry. The seed fine fraction showed significant inhibition of P fimbria-mediated haemagglutination assay of uropathogenic Escherichia coli. The seed coarse fraction significantly reduced NO and IL-6 production and iNOS expression in activated macrophages. Fermentation did not affect antimicrobial activity, but slight increase in activity was detected in dry fractions. The results indicate the potential of cloudberry in pharma or health food applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biofouling behavior and performance of forward osmosis membranes with bioinspired surface modification in osmotic membrane bioreactor.

PubMed

Li, Fang; Cheng, Qianxun; Tian, Qing; Yang, Bo; Chen, Qianyuan

2016-07-01

Forward osmosis (FO) has received considerable interest for water and energy related applications in recent years. Biofouling behavior and performance of cellulose triacetate (CTA) forward osmosis membranes with bioinspired surface modification via polydopamine (PD) coating and poly (ethylene glycol) (PEG) grafting (PD-g-PEG) in a submerged osmotic membrane bioreactor (OMBR) were investigated in this work. The modified membranes exhibited lower flux decline than the pristine one in OMBR, confirming that the bioinspired surface modification improved the antifouling ability of the CTA FO membrane. The result showed that the decline of membrane flux related to the increase of the salinity and MLSS concentration of the mixed liquid. It was concluded that the antifouling ability of modified membranes ascribed to the change of surface morphology in addition to the improvement of membrane hydrophilicity. The bioinspired surface modifications might improve the anti-adhesion for the biopolymers and biocake. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Results of patch tests using basic allergens in construction workers].

PubMed

Kieć-Swierczyńska, M

1983-01-01

A group of 853 construction industry workers exposed to irritants and allergens (mainly cement, lime, sand, water, lubricants and antiadhesive oils and a control group of 74 subjects (sawers) underwent patch tests after Jadassohn--Bloch with seven allergens most common in the construction industry working environment (compounds of chromium, nickel and cobalt, turpentine and three rubber allergens--mercantobenzothiazole, thiocarbamoyl and diphenylguanidine). Allergy was found in 25.5% of the construction industry workers, in this 7.7% were those with eczema and dermatitis, 17.8%--those with latent allergy (in 12.2% allergy was accompanied by dermatoses of non-allergic etiology, 5.6% construction workers no skin changes). The highest number of skin positive tests was that with chromium (22.4% of affected workers) and cobalt (12.4%). Most susceptible to allergy were: painters, bricklayers, carpenters, joiners, reinforcing concretors, terrazers, concretors, electricians, smiths and reinforcers. In addition, allergy was found to be dependent on age and length of employment.

Enzymatic Synthesis and Purification of Galactosylated Chitosan Oligosaccharides Reducing Adhesion of Enterotoxigenic Escherichia coli K88.

PubMed

Yan, Ya Lu; Hu, Ying; Simpson, David J; Gänzle, Michael G

2017-06-28

Enterotoxigenic Escherichia coli (ETEC) K88 causes diarrhea in weaned piglets and represent a suitable model system for ETEC causing childhood diarrhea. This study aimed to evaluate the effects of oligosaccharides against ETEC K88 adhesion to porcine erythrocytes with two bioassays. Galactosylated chitosan-oligosaccharides (Gal-COS) were synthesized through transgalactosylation by β-galactosidase. Fractions 2-5 of Gal-COS were obtained through cation exchange and size exclusion chromatography. Fractions 2-5 of acetylated Gal-COS were obtained through chemical acetylation followed by size exclusion chromatography. Gal-COS F2 containing the largest oligosaccharides had the highest antiadhesion activity with the minimum inhibitory concentration of 0.22 g/L, followed by F3 and F4. Acetylation of Gal-COS decreased their ability to reduce ETEC K88 adhesion. The composition of active oligosaccharides was determined with LC-MS. Galactosylation of COS produces oligosaccharides which reduce ETEC K88 adhesion; moreover, resulting oligosaccharides match the composition of human milk oligosaccharides, which prevent adhesion of multiple pathogens.

Effects of Antiadhesion preparation on free fibrinogen and fibrin degrading products in abdominal exudates of rabbits postoperatively

PubMed Central

Wang, You-Li; Pan, Cheng-En; Yang, Ping-Lin; Tian, Yuan; Pei, Shu-Wen; Dong, Ming

2004-01-01

AIM: To observe effects of ACOL on fibrinogen (FIB), fibrin degrading products (FDP) and changes of FIB and FDP concentration in rabbits with intro-abdominal exudates during 7 d after major abdominal surgery. METHODS: Sixty New Zealand rabbits were randomly divided into 4 groups: ACOL group, the control group, DCT group and the normal group. After being modeled, except the normal group, the other 3 groups were treated with different ways for a week; the intro-abdominal exudates of rabbits in the 4 groups were drawn for FIB and FDP measurement once daily during 7 d after major abdominal surgery. RESULTS: FIB and FDP in the intro-abdominal exudates altered in a regular way and ACOL could change the concentration of FIB and FDP in the intra-abdominal exudates after major abdominal surgery. CONCLUSION: ACOL can prevent intestinal adhesion by reducing the concentration of FIB and raising that of FDP in the intro-abdominal exudates after major abdominal surgery. PMID:15309738

The tumor suppressor DAPK is reciprocally regulated by tyrosine kinase Src and phosphatase LAR.

PubMed

Wang, Won-Jing; Kuo, Jean-Cheng; Ku, Wei; Lee, Yu-Ru; Lin, Feng-Chi; Chang, Yih-Leong; Lin, Yu-Min; Chen, Chun-Hau; Huang, Yuan-Ping; Chiang, Meng-Jung; Yeh, Sheng-Wen; Wu, Pei-Rung; Shen, Che-Hung; Wu, Chen-Tu; Chen, Ruey-Hwa

2007-09-07

Death-associated protein kinase (DAPK) is a calmodulin-regulated serine/threonine kinase and elicits tumor suppression function through inhibiting cell adhesion/migration and promoting apoptosis. Despite these biological functions, the signaling mechanisms through which DAPK is regulated remain largely elusive. Here, we show that the leukocyte common antigen-related (LAR) tyrosine phosphatase dephosphorylates DAPK at pY491/492 to stimulate the catalytic, proapoptotic, and antiadhesion/antimigration activities of DAPK. Conversely, Src phosphorylates DAPK at Y491/492, which induces DAPK intra-/intermolecular interaction and inactivation. Upon EGF stimulation, a rapid Src activation leads to subsequent LAR downregulation, and these two events act in synergism to inactivate DAPK, thereby facilitating tumor cell migration and invasion toward EGF. Finally, DAPK Y491/492 hyperphosphorylation is found in human cancers in which Src activity is aberrantly elevated. These results identify LAR and Src as a DAPK regulator through their reciprocal modification of DAPK Y491/492 residues and establish a functional link of this DAPK-regulatory circuit to tumor progression.

Antivirulence Properties of Probiotics in Combating Microbial Pathogenesis.

PubMed

Surendran Nair, M; Amalaradjou, M A; Venkitanarayanan, K

2017-01-01

Probiotics are nonpathogenic microorganisms that confer a health benefit on the host when administered in adequate amounts. Ample evidence is documented to support the potential application of probiotics for the prevention and treatment of infections. Health benefits of probiotics include prevention of diarrhea, including antibiotic-associated diarrhea and traveler's diarrhea, atopic eczema, dental carries, colorectal cancers, and treatment of inflammatory bowel disease. The cumulative body of scientific evidence that demonstrates the beneficial effects of probiotics on health and disease prevention has made probiotics increasingly important as a part of human nutrition and led to a surge in the demand for probiotics in clinical applications and as functional foods. The ability of probiotics to promote health is attributed to the various beneficial effects exerted by these microorganisms on the host. These include lactose metabolism and food digestion, production of antimicrobial peptides and control of enteric infections, anticarcinogenic properties, immunologic enhancement, enhancement of short-chain fatty acid production, antiatherogenic and cholesterol-lowering attributes, regulatory role in allergy, protection against vaginal or urinary tract infections, increased nutritional value, maintenance of epithelial integrity and barrier, stimulation of repair mechanism in cells, and maintenance and reestablishment of well-balanced indigenous intestinal and respiratory microbial communities. Most of these attributes primarily focus on the effect of probiotic supplementation on the host. Hence, in most cases, it can be concluded that the ability of a probiotic to protect the host from infection is an indirect result of promoting overall health and well-being. However, probiotics also exert a direct effect on invading microorganisms. The direct modes of action resulting in the elimination of pathogens include inhibition of pathogen replication by producing antimicrobial substances like bacteriocins, competition for limiting resources in the host, antitoxin effect, inhibition of virulence, antiadhesive and antiinvasive effects, and competitive exclusion by competition for binding sites or stimulation of epithelial barrier function. Although much has been documented about the ability of probiotics to promote host health, there is limited discussion on the above mentioned effects of probiotics on pathogens. Being in an era of antibiotic resistance, a better understanding of this complex probiotic-pathogen interaction is critical for development of effective strategies to control infections. Therefore, this chapter will focus on the ability of probiotics to directly modulate the infectious nature of pathogens and the underlying mechanisms that mediate these effects. Copyright © 2017 Elsevier Inc. All rights reserved.

Chemical modification of polyvinyl chloride and silicone elastomer in inhibiting adhesion of Aeromonas hydrophila.

PubMed

Kregiel, Dorota; Berlowska, Joanna; Mizerska, Urszula; Fortuniak, Witold; Chojnowski, Julian; Ambroziak, Wojciech

2013-07-01

Disease-causing bacteria of the genus Aeromonas are able to adhere to pipe materials, colonizing the surfaces and forming biofilms in water distribution systems. The aim of our research was to study how the modification of materials used commonly in the water industry can reduce bacterial cell attachment. Polyvinyl chloride and silicone elastomer surfaces were activated and modified with reactive organo-silanes by coupling or co-crosslinking silanes with the native material. Both the native and modified surfaces were tested using the bacterial strain Aeromonas hydrophila, which was isolated from the Polish water distribution system. The surface tension of both the native and modified surfaces was measured. To determine cell viability and bacterial adhesion two methods were used, namely plate count and luminometry. Results were expressed in colony-forming units (c.f.u.) and in relative light units (RLU) per cm(2). Almost all the chemically modified surfaces exhibited higher anti-adhesive and anti-microbial properties in comparison to the native surfaces. Among the modifying agents examined, poly[dimethylsiloxane-co-(N,N-dimethyl-N-n-octylammoniopropyl chloride) methylsiloxane)] terminated with hydroxydimethylsilyl groups (20 %) in silicone elastomer gave the most desirable results. The surface tension of this modifier, was comparable to the non-polar native surface. However, almost half of this value was due to the result of polar forces. In this case, in an adhesion analysis, only 1 RLU cm(-2) and less than 1 c.f.u. cm(-2) were noted. For the native gumosil, the results were 9,375 RLU cm(-2) and 2.5 × 10(8) c.f.u. cm(-2), respectively. The antibacterial activity of active organo-silanes was associated only with the carrier surface because no antibacterial compounds were detected in liquid culture media, in concentrations that were able to inhibit cell growth.

Composition and Antibacterial Activity of the Essential Oils of Orthosiphon stamineus Benth and Ficus deltoidea Jack against Pathogenic Oral Bacteria.

PubMed

Azizan, Nuramirah; Mohd Said, Shahida; Zainal Abidin, Zamirah; Jantan, Ibrahim

2017-12-05

In this study, the essential oils of Orthosiphon stamineus Benth and Ficus deltoidea Jack were evaluated for their antibacterial activity against invasive oral pathogens, namely Enterococcus faecalis , Streptococcus mutans , Streptococcus mitis , Streptococcus salivarius , Aggregatibacter actinomycetemcomitans , Porphyromonas gingivalis and Fusobacterium nucleatum . Chemical composition of the oils was analyzed using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antibacterial activity of the oils and their major constituents were investigated using the broth microdilution method (minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC)). Susceptibility test, anti-adhesion, anti-biofilm, checkerboard and time-kill assays were also carried out. Physiological changes of the bacterial cells after exposure to the oils were observed under the field emission scanning electron microscope (FESEM). O. stamineus and F. deltoidea oils mainly consisted of sesquiterpenoids (44.6% and 60.9%, respectively), and β-caryophyllene was the most abundant compound in both oils (26.3% and 36.3%, respectively). Other compounds present in O. stamineus were α-humulene (5.1%) and eugenol (8.1%), while α-humulene (5.5%) and germacrene D (7.7%) were dominant in F. deltoidea . The oils of both plants showed moderate to strong inhibition against all tested bacteria with MIC and MBC values ranging 0.63-2.5 mg/mL. However, none showed any inhibition on monospecies biofilms. The time-kill assay showed that combination of both oils with amoxicillin at concentrations of 1× and 2× MIC values demonstrated additive antibacterial effect. The FESEM study showed that both oils produced significant alterations on the cells of Gram-negative bacteria as they became pleomorphic and lysed. In conclusion, the study indicated that the oils of O. stamineus and F. deltoidea possessed moderate to strong antibacterial properties against the seven strains pathogenic oral bacteria and may have caused disturbances of membrane structure or cell wall of the bacteria.

A Novel Assay for Easy and Rapid Quantification of Helicobacter pylori Adhesion.

PubMed

Skindersoe, Mette E; Rasmussen, Lone; Andersen, Leif P; Krogfelt, Karen A

2015-06-01

Reducing adhesion of Helicobacter pylori to gastric epithelial cells could be a new way to counteract infections with this organism. We here present a novel method for quantification of Helicobacter pylori adhesion to cells. Helicobacter pylori is allowed to adhere to AGS or MKN45g cells in a 96-well microtiter plate. Then wells are added saponin, which lyses the cells without affecting the bacteria. After addition of alamarBlue(®) (resazurin) and 1- to 2-hour incubation, fluorescence measurements can be used to quantify the number of adherent bacteria. By use of the method, we demonstrate that adhesion of both a sabA and babA deletion mutant of H. pylori is significantly reduced compared to the wild type. The method offers a number of applications and may be used to compare the adherence potential of different strains of H. pylori to either cells or different materials or to screen for potential anti-adhesive compounds. The results presented here suggest that this easy and reproducible assay is well suited for quantitative investigation of H. pylori adhesion. © 2015 John Wiley & Sons Ltd.

Titanium surfaces immobilized with the major antimicrobial fragment FK-16 of human cathelicidin LL-37 are potent against multiple antibiotic-resistant bacteria.

PubMed

Mishra, Biswajit; Wang, Guangshun

2017-08-01

Infections on implanted medical devices are a challenging problem, especially when bacteria form difficult-to-treat biofilms. Antimicrobial peptides are considered to be a solution due to their potency against antibiotic-resistant superbugs. Previously, the authors' laboratory demonstrated the prevention of staphylococcal biofilm formation in an animal catheter model by injecting merecidin (formerly known as 17BIPHE2), a peptide engineered based on the only human cathelicidin. This study documents an alternative solution via covalent immobilization of FK-16, amino acid sequence FKRIVQRIKDFLRNLV-amide, which corresponds to the major antimicrobial region (residues 17-32) of LL-37. FK-16 is superior to the longer peptide LL-37 in terms of synthesis cost and the shorter peptide KR-12 in terms of activity spectrum. Indeed, the FK16-coated titanium surface showed a broad-spectrum activity against the ESKAPE pathogens, including Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species. It also demonstrated anti-adhesion and biofilm inhibition capabilities against both S. aureus and E. coli.

In vivo studies of sickle red blood cells.

PubMed

Kaul, Dhananjay K; Fabry, Mary E

2004-03-01

The defining clinical feature of sickle cell anemia is periodic occurrence of painful vasoocclusive crisis. Factors that promote trapping and sickling of red cells in the microcirculation are likely to trigger vasoocclusion. The marked red cell heterogeneity in sickle blood and abnormal adhesion of sickle red cells to vascular endothelium would be major disruptive influences. Using ex vivo and in vivo models, the authors show how to dissect the relative contribution of heterogeneous sickle red cell classes to adhesive and obstructive events. These studies revealed that (1) both rheological abnormalities and adhesion of sickle red cells contribute to their abnormal hemodynamic behavior, (2) venules are the sites of sickle cell adhesion, and (3) sickle red cell deformability plays an important role in adhesive and obstructive events. Preferential adhesion of deformable sickle red cells in postcapillary venules followed by selective trapping of dense sickle red cells could result in vasoocclusion. An updated version of this 2-step model is presented. The multifactorial nature of sickle red cell adhesion needs to be considered in designing antiadhesive therapy in vivo.

Adherent-invasive Escherichia coli in inflammatory bowel disease.

PubMed

Palmela, Carolina; Chevarin, Caroline; Xu, Zhilu; Torres, Joana; Sevrin, Gwladys; Hirten, Robert; Barnich, Nicolas; Ng, Siew C; Colombel, Jean-Frederic

2018-03-01

Intestinal microbiome dysbiosis has been consistently described in patients with IBD. In the last decades, Escherichia coli , and the adherent-invasive E coli (AIEC) pathotype in particular, has been implicated in the pathogenesis of IBD. Since the discovery of AIEC, two decades ago, progress has been made in unravelling these bacteria characteristics and its interaction with the gut immune system. The mechanisms of adhesion of AIEC to intestinal epithelial cells (via FimH and cell adhesion molecule 6) and its ability to escape autophagy when inside macrophages are reviewed here. We also explore the existing data on the prevalence of AIEC in patients with Crohn's disease and UC, and the association between the presence of AIEC and disease location, activity and postoperative recurrence. Finally, we highlight potential therapeutic strategies targeting AIEC colonisation of gut mucosa, including the use of phage therapy, bacteriocins and antiadhesive molecules. These strategies may open new avenues for the prevention and treatment of IBD in the future. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Prevention of peritendinous adhesions with electrospun ibuprofen-loaded poly(L-lactic acid)-polyethylene glycol fibrous membranes.

PubMed

Liu, Shen; Hu, Changmin; Li, Fengfeng; Li, Xu-jun; Cui, Wenguo; Fan, Cunyi

2013-02-01

Physical barriers are commonly used to reduce peritendinous adhesion after injury. However, the inflammatory response to surgery cannot be prevented. This study was designed to evaluate the ability of ibuprofen-loaded poly(l-lactic acid)-polyethylene glycol (PELA) diblock copolymer fibrous membranes in preventing adhesion formation and reduce inflammation. Electrospun PELA fibrous membranes underwent mechanical testing and were characterized by morphology, surface wettability, drug release, and degradation. Results of an in vitro drug release study showed that a burst release was followed by sustained release from fibrous membranes with high initial ibuprofen content. Fewer L929 mouse fibroblasts adhered to and proliferated on the ibuprofen-loaded PELA fibrous membrane compared with tissue culture plates or PELA fibrous membrane without ibuprofen. In a chicken model of flexor digitorum profundus tendon surgery, the ibuprofen-loaded PELA fibrous membranes prevented tissue adhesion and significantly reduced inflammation. Taken together, these results demonstrate that ibuprofen-loaded PELA fibrous membranes prevent peritendinous adhesion formation better than membranes that do not contain ibuprofen, through anti-adhesion and anti-inflammatory actions.

Quantitative comparison of a human cancer cell surface proteome between interphase and mitosis.

PubMed

Özlü, Nurhan; Qureshi, Mohammad H; Toyoda, Yusuke; Renard, Bernhard Y; Mollaoglu, Gürkan; Özkan, Nazlı E; Bulbul, Selda; Poser, Ina; Timm, Wiebke; Hyman, Anthony A; Mitchison, Timothy J; Steen, Judith A

2015-01-13

The cell surface is the cellular compartment responsible for communication with the environment. The interior of mammalian cells undergoes dramatic reorganization when cells enter mitosis. These changes are triggered by activation of the CDK1 kinase and have been studied extensively. In contrast, very little is known of the cell surface changes during cell division. We undertook a quantitative proteomic comparison of cell surface-exposed proteins in human cancer cells that were tightly synchronized in mitosis or interphase. Six hundred and twenty-eight surface and surface-associated proteins in HeLa cells were identified; of these, 27 were significantly enriched at the cell surface in mitosis and 37 in interphase. Using imaging techniques, we confirmed the mitosis-selective cell surface localization of protocadherin PCDH7, a member of a family with anti-adhesive roles in embryos. We show that PCDH7 is required for development of full mitotic rounding pressure at the onset of mitosis. Our analysis provided basic information on how cell cycle progression affects the cell surface. It also provides potential pharmacodynamic biomarkers for anti-mitotic cancer chemotherapy. © 2014 The Authors.

Quantitative comparison of a human cancer cell surface proteome between interphase and mitosis

PubMed Central

Özlü, Nurhan; Qureshi, Mohammad H; Toyoda, Yusuke; Renard, Bernhard Y; Mollaoglu, Gürkan; Özkan, Nazlı E; Bulbul, Selda; Poser, Ina; Timm, Wiebke; Hyman, Anthony A; Mitchison, Timothy J; Steen, Judith A

2015-01-01

The cell surface is the cellular compartment responsible for communication with the environment. The interior of mammalian cells undergoes dramatic reorganization when cells enter mitosis. These changes are triggered by activation of the CDK1 kinase and have been studied extensively. In contrast, very little is known of the cell surface changes during cell division. We undertook a quantitative proteomic comparison of cell surface-exposed proteins in human cancer cells that were tightly synchronized in mitosis or interphase. Six hundred and twenty-eight surface and surface-associated proteins in HeLa cells were identified; of these, 27 were significantly enriched at the cell surface in mitosis and 37 in interphase. Using imaging techniques, we confirmed the mitosis-selective cell surface localization of protocadherin PCDH7, a member of a family with anti-adhesive roles in embryos. We show that PCDH7 is required for development of full mitotic rounding pressure at the onset of mitosis. Our analysis provided basic information on how cell cycle progression affects the cell surface. It also provides potential pharmacodynamic biomarkers for anti-mitotic cancer chemotherapy. PMID:25476450

A novel TaqI polymorphism in the coding region of the ovine TNXB gene in the MHC class III region: morphostructural and physiological influences.

PubMed

Ajayi, Oyeyemi O; Adefenwa, Mufliat A; Agaviezor, Brilliant O; Ikeobi, Christian O N; Wheto, Matthew; Okpeku, Moses; Amusan, Samuel A; Yakubu, Abdulmojeed; De Donato, Marcos; Peters, Sunday O; Imumorin, Ikhide G

2014-02-01

The tenascin-XB (TNXB) gene has antiadhesive effects, functions in matrix maturation in connective tissues, and localizes to the major histocompatibility complex class III region. We hypothesized that it may influence adaptive physiological response through an effect on blood vessel function. We identified a novel g.1324 A→G polymorphism at a TaqI recognition site in a 454 bp fragment of ovine TNXB and genotyped it in 150 Nigerian sheep using PCR-RFLP. The missense mutation changes glutamic acid (GAA) to glycine (GGA). Among SNP genotypes, significant differences (P < 0.05) were observed in body weight and fore cannon bone length. Interaction effects of breed, SNP genotype, and geographic location had a significant effect (P < 0.05) on chest girth. The SNP genotype was significantly (P < 0.05) associated with physiological traits of pulse rate and skin temperature. The observed effect of this novel polymorphism may be mediated through its role in connective tissue biology, requiring further association and functional studies.

The effect of montelukast and antiadhesion barrier solution on the capsule formation after insertion of silicone implants in a white rat model.

PubMed

Yang, J-D; Kwon, O-H; Lee, J-W; Chung, H-Y; Cho, B-C; Park, H-Y; Kim, T-G

2013-01-01

Capsular contracture is one of the most severe complications that can occur in breast surgery following silicone implant insertion. The purpose of this study was to investigate the effect of montelukast and antiadhesion barrier solution (AABS) on reducing capsular formation and their possible synergism. This study was approved by the Animal Ethics Committee (Reference No. KNU 2012-33) and was conducted in accordance with the Kyungpook National University - Institutional Animal Care and Use Committee, Animal Ethics Committee. The experiments in this study were conducted in vivo in 4 groups of 24 rats. Following silicone implant insertion, the pocket was injected with different agents. Group I (control group) was given normal saline injections into the pocket and fed with pure water. Group II was given injections of AABS and fed with pure water. Group III was given injections of normal saline and the medication montelukast during the experimental period. Group IV was given injections of AABS and montelukast as postoperative medication. Peri-implant capsules were excised after 8 weeks and were evaluated for transparency, inflammatory cell content, capsule thickness, collagen pattern and TGF-β expression. The capsules in the experimental groups (i.e., groups II-IV) were significantly more transparent than those in group I (controls; p < 0.05, Student's t test). The mean capsule thickness of the experimental groups II (296 ± 14.76 μm), III (280 ± 14.77 μm) and IV (276 ± 39.28 μm) was smaller than that of the control group I (361 ± 35.43 μm). Compared to the control group, the histologic findings in the experimental groups suggested a decreased inflammatory response occurring in the peri-implant capsules as they exhibited minor vascularization and a reduced number of mast cells and macrophages. The collagen patterns in the experimental groups were of a lower density than in the control group with the former showing a loose, tidy collagen pattern. The amounts of TGF-β and collagen I were higher in the control group than in the experimental groups. Group IV (the synergic effect group) had a more pronounced effect on all the parameters examined than that in groups II and III with separate drug administration. Montelukast and AABS reduced the thickness, the inflammatory cell infiltrate and the myofibroblast content of the peri-implant capsules around silicone implants in this white rat model. They lowered the expression of the fibrotic mediator, TGF-β, and inhibited the peri-implant capsular fibrosis. Therefore, montelukast and AABS are effective in the reduction of silicone-induced peri-implant capsular formation.

Cellular response of healing tissue to DegraPol tube implantation in rabbit Achilles tendon rupture repair: an in vivo histomorphometric study.

PubMed

Buschmann, Johanna; Meier-Bürgisser, Gabriella; Bonavoglia, Eliana; Neuenschwander, Peter; Milleret, Vincent; Giovanoli, Pietro; Calcagni, Maurizio

2013-05-01

In tendon rupture repair, improvements such as higher primary repair strength, anti-adhesion and accelerated healing are needed. We developed a potential carrier system of an electrospun DegraPol tube, which was tightly implanted around a transected and conventionally sutured rabbit Achilles tendon. Histomorphometric analysis of the tendon tissue 12 weeks postoperation showed that the tenocyte density, tenocyte morphology and number of inflammation zones were statistically equivalent, whether or not DegraPol tube was implanted; only the collagen fibres were slightly less parallelly orientated in the tube-treated case. Comparison of rabbits that were operated on both hind legs with ones that were operated on only one hind leg showed that there were significantly more inflammation zones in the two-leg cases compared to the one-leg cases, while the implantation of a DegraPol tube had no such adverse effects. These findings are a prerequisite for using DegraPol tube as a carrier system for growth factors, cytokines or stem cells in order to accelerate the healing process of tendon tissue. Copyright © 2012 John Wiley & Sons, Ltd.

Topical non-barrier agents for postoperative adhesion prevention in animal models.

PubMed

Imai, Atsushi; Suzuki, Noriko

2010-04-01

Pelvic adhesion can form as a result of inflammation, endometriosis or surgical trauma. Most surgical procedures performed by obstetrician-gynecologists are associated with pelvic adhesions that may cause subsequent serious sequelae, including small bowel obstruction, infertility, chronic pelvic pain, and difficulty in postoperative treatment, including complexity during subsequent surgical procedures. An increasing number of adhesion reduction agents, in the form of site-specific and broad-coverage barriers and solutions, are becoming available to surgical teams. The most widely studied strategies include placing synthetic barrier agents between the pelvic structures. Most of the adhesions in the barrier-treated patients develop in uncovered areas in the abdomen. This fact suggests that the application of liquid or gel anti-adhesive agents to cover all potential peritoneal lesions, together with the use of barrier agents, may reduce the formation of postoperative adhesions. This article introduces the topical choices available for adhesion prevention mentioned in preliminary clinical applications and animal models. To date there is no substantial evidence that their use reduces the incidence of postoperative adhesions. In combination with good surgical techniques, these non-barrier agents may play an important role in adhesion reduction. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Imprint Molding of a Microfluidic Optical Cell on Thermoplastics with Reduced Surface Roughness for the Detection of Copper Ions.

PubMed

Wu, Jing; Lee, Nae Yoon

2016-01-01

Here, we introduce a simple and facile technique for fabricating microfluidic optical cells by utilizing a micropatterned polymer mold, followed by imprinting on thermoplastic substrates. This process has reduced the surface roughness of the microchannel, making it suitable for microscale optical measurements. The micropatterned polymer mold was fabricated by first micromilling on a poly(methylmethacrylate) (PMMA) substrate, and then transferring the micropattern onto an ultraviolet (UV)-curable optical adhesive. After an anti-adhesion treatment of the polymer mold fabricated using the UV-curable optical adhesive, the polymer mold was used repeatedly for imprinting onto various thermoplastics, such as PMMA, polycarbonate (PC), and poly(ethyleneterephthalate) (PET). The roughness values for the PMMA, PC, and PET microchannels were approximately 11.3, 20.3, and 14.2 nm, respectively, as compared to those obtained by micromilling alone, which were 15.9, 76.8, and 207.5 nm, respectively. Using the imprint-molded thermoplastic optical cell, rhodamine B and copper ions were successfully quantified. The reduced roughness of the microchannel surface resulted in improved sensitivity and reduced noise, paving the way for integration of the detection module so as to realize totally integrated microdevices.

Prevention of intra-abdominal adhesion by bi-layer electrospun membrane.

PubMed

Jiang, Shichao; Wang, Wei; Yan, Hede; Fan, Cunyi

2013-06-04

The aim of this study was to compare the anti-adhesion efficacy of a bi-layer electrospun fibrous membrane consisting of hyaluronic acid-loaded poly(ε-caprolactone) (PCL) fibrous membrane as the inner layer and PCL fibrous membrane as the outer layer with a single-layer PCL electrospun fibrous membrane in a rat cecum abrasion model. The rat model utilized a cecal abrasion and abdominal wall insult surgical protocol. The bi-layer and PCL membranes were applied between the cecum and the abdominal wall, respectively. Control animals did not receive any treatment. After postoperative day 14, a visual semiquantitative grading scale was used to grade the extent of adhesion. Histological analysis was performed to reveal the features of adhesion tissues. Bi-layer membrane treated animals showed significantly lower adhesion scores than control animals (p < 0.05) and a lower adhesion score compared with the PCL membrane. Histological analysis of the bi-layer membrane treated rat rarely demonstrated tissue adhesion while that of the PCL membrane treated rat and control rat showed loose and dense adhesion tissues, respectively. Bi-layer membrane can efficiently prevent adhesion formation in abdominal cavity and showed a significantly decreased adhesion tissue formation compared with the control.

Oligosaccharide receptor mimics inhibit Legionella pneumophila attachment to human respiratory epithelial cells.

PubMed

Thomas, Richard J; Brooks, Tim J

2004-02-01

Legionnaire's disease is caused by the intracellular pathogen Legionella pneumophila, presenting as an acute pneumonia. Attachment is the key step during infection, often relying on an interaction between host cell oligosaccharides and bacterial adhesins. Inhibition of this interaction by receptor mimics offers possible novel therapeutic treatments. L. pneumophila attachment to the A549 cell line was significantly reduced by treatment with tunicamycin (73.6%) and sodium metaperiodate (63.7%). This indicates the importance of cell surface oligosaccharide chains in adhesion. A number of putative anti-adhesion compounds inhibited attachment to the A549 and U937 cell lines. The most inhibitory compounds were polymeric saccharides, GalNAcbeta1-4Gal, Galbeta1-4GlcNAc and para-nitrophenol. These compounds inhibited adhesion to a range of human respiratory cell lines, including nasal epithelial, bronchial epithelial and alveolar epithelial cell lines and the human monocytic cell line, U937. Some eukaryotic receptors for L. pneumophila were determined to be the glycolipids, asialo-GM1 and asialo-GM2 that contain the inhibitory saccharide moiety, GalNAcbeta1-4Gal. The identified compounds have the potential to be used as novel treatments for Legionnaire's disease.

Non-conventional therapeutics for oral infections

PubMed Central

Allaker, Robert P; Ian Douglas, CW

2015-01-01

As our knowledge of host-microbial interactions within the oral cavity increases, future treatments are likely to be more targeted. For example, efforts to target a single species or key virulence factors that they produce, while maintaining the natural balance of the resident oral microbiota that acts to modulate the host immune response would be an advantage. Targeted approaches may be directed at the black-pigmented anaerobes, Porphyromonas gingivalis and Prevotella intermedia, associated with periodontitis. Such pigments provide an opportunity for targeted phototherapy with high-intensity monochromatic light. Functional inhibition approaches, including the use of enzyme inhibitors, are also being explored to control periodontitis. More general disruption of dental plaque through the use of enzymes and detergents, alone and in combination, shows much promise. The use of probiotics and prebiotics to improve gastrointestinal health has now led to an interest in using these approaches to control oral disease. More recently the potential of antimicrobial peptides and nanotechnology, through the application of nanoparticles with biocidal, anti-adhesive and delivery capabilities, has been explored. The aim of this review is to consider the current status as regards non-conventional treatment approaches for oral infections with particular emphasis on the plaque-related diseases. PMID:25668296

Biological therapy targeting the IL-23/IL-17 axis in inflammatory bowel disease.

PubMed

Verstockt, Bram; Van Assche, Gert; Vermeire, Séverine; Ferrante, Marc

2017-01-01

As many inflammatory bowel disease (IBD) patients do not benefit from long-term anti-tumour necrosis factor treatment, new anti-inflammatories are urgently needed. After the discovery of the interleukin (IL) 23/17 axis being pivotal in IBD pathogenesis, many different compounds were developed, targeting different components within this pathway. Areas covered: A literature search to March 2016 was performed to identify the most relevant reports on the role of the IL-23/IL-17 axis in IBD and on the different molecules targeting this pathway. First, the authors briefly summarize the immunology of the IL-23/IL-17 pathway to elucidate the mode of action of all different agents. Second, they describe all different molecules targeting this pathway. Besides discussing efficacy and safety data, they also explore immunogenicity, exposure during pregnancy and pharmacokinetics. Expert opinion: A new era in IBD treatment has recently been initiated: besides immunomodulators and TNF-antagonists, anti-adhesion molecules and monoclonal antibodies targeting the IL-23/IL-17 pathway have been developed. Biomarkers for personalized medicine are urgently needed. This therapeutic (r)evolution will further improve disease-related and patient-reported outcome, though a lot of questions should still be addressed in future years.

Logarithmic contact time dependence of adhesion force and its dominant role among the effects of AFM experimental parameters under low humidity

NASA Astrophysics Data System (ADS)

Lai, Tianmao; Meng, Yonggang

2017-10-01

The influences of contact time, normal load, piezo velocity, and measurement number of times on the adhesion force between two silicon surfaces were studied with an atomic force microscope (AFM) at low humidity (17-15%). Results show that the adhesion force is time-dependent and increases logarithmically with contact time until saturation is reached, which is related with the growing size of a water bridge between them. The contact time plays a dominant role among these parameters. The adhesion forces with different normal loads and piezo velocities can be quantitatively obtained just by figuring out the length of contact time, provided that the contact time dependence is known. The time-dependent adhesion force with repeated contacts at one location usually increases first sharply and then slowly with measurement number of times until saturation is reached, which is in accordance with the contact time dependence. The behavior of the adhesion force with repeated contacts can be adjusted by the lengths of contact time and non-contact time. These results may help facilitate the anti-adhesion design of silicon-based microscale systems working under low humidity.

Hydrogel brushes grafted from stainless steel via surface-initiated atom transfer radical polymerization for marine antifouling

NASA Astrophysics Data System (ADS)

Wang, Jingjing; Wei, Jun

2016-09-01

Crosslinked hydrogel brushes were grafted from stainless steel (SS) surfaces for marine antifouling. The brushes were prepared by surface-initiated atom transfer radical polymerization (SI-ATRP) of 2-methacryloyloxyethyl phosphorylcholine (MPC) and poly(ethylene glycol) methyl ether methacrylate (PEGMA) respectively with different fractions of crosslinker in the feed. The grafted layers prepared with different thickness were characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), ellipsometry and water contact angle measurements. With the increase in the fraction of crosslinker in the feed, the thickness of the grafted layer increased and the surface became smooth. All the brush-coated SS surfaces could effectively reduce the adhesion of bacteria and microalgae and settlement of barnacle cyprids, as compared to the pristine SS surface. The antifouling efficacy of the PEGMA polymer (PPEGMA)-grafted surface was higher than that of the MPC polymer (PMPC)-grafted surfaces. Furthermore, the crosslinked hydrogel brush-grafted surfaces exhibited better fouling resistance than the non-crosslinked polymer brush-grafted surfaces, and the antifouling efficacy increased with the crosslinking density. These hydrogel coatings of low toxicity and excellent anti-adhesive characteristics suggested their useful applications as environmentally friendly antifouling coatings.

Nanoporous aerogel as a bacteria repelling hygienic material for healthcare environment

NASA Astrophysics Data System (ADS)

Oh, Jun Kyun; Kohli, Nandita; Zhang, Yuanzhong; Min, Younjin; Jayaraman, Arul; Cisneros-Zevallos, Luis; Akbulut, Mustafa

2016-02-01

Healthcare-associated infections (HAIs) caused by pathogenic bacteria are a worldwide problem and responsible for numerous cases of morbidity and mortality. Exogenous cross-contamination is one of the main mechanisms contributing to such infections. This work investigates the potential of hydrophobically modified nanoporous silica aerogel as an antiadhesive hygienic material that can inhibit exogenous bacterial contamination. Nanoporous silica aerogels were synthesized via sol-gel polymerization of tetraethyl orthosilicate and hydrophobized using trimethylsilyl chloride. Bacterial adhesion characteristics were evaluated via dip-inoculation in suspensions of Gram-negative Escherichia coli O157:H7 and Gram-positive Staphylococcus aureus. The attachment of E. coli O157:H7 and S. aureus to hydrophobic nanoporous silica aerogel (HNSA) was found to be significantly lower than that to hydrophilic and hydrophobic nonporous silica materials: 99.91% (E. coli O157:H7) and 99.93% (S. aureus) reduction in comparison to hydrophilic nonporous silica, and 82.95% (E. coli O157:H7) and 84.90% (S. aureus) reduction in comparison to hydrophobic nonporous silica. These results suggest that the use of HNSA as surfaces that come into contact with bacterial pathogens in the healthcare environment can improve bacterial hygiene, and therefore may reduce the rate of HAIs.

Nanoporous aerogel as a bacteria repelling hygienic material for healthcare environment.

PubMed

Oh, Jun Kyun; Kohli, Nandita; Zhang, Yuanzhong; Min, Younjin; Jayaraman, Arul; Cisneros-Zevallos, Luis; Akbulut, Mustafa

2016-02-26

Healthcare-associated infections (HAIs) caused by pathogenic bacteria are a worldwide problem and responsible for numerous cases of morbidity and mortality. Exogenous cross-contamination is one of the main mechanisms contributing to such infections. This work investigates the potential of hydrophobically modified nanoporous silica aerogel as an antiadhesive hygienic material that can inhibit exogenous bacterial contamination. Nanoporous silica aerogels were synthesized via sol-gel polymerization of tetraethyl orthosilicate and hydrophobized using trimethylsilyl chloride. Bacterial adhesion characteristics were evaluated via dip-inoculation in suspensions of Gram-negative Escherichia coli O157:H7 and Gram-positive Staphylococcus aureus. The attachment of E. coli O157:H7 and S. aureus to hydrophobic nanoporous silica aerogel (HNSA) was found to be significantly lower than that to hydrophilic and hydrophobic nonporous silica materials: 99.91% (E. coli O157:H7) and 99.93% (S. aureus) reduction in comparison to hydrophilic nonporous silica, and 82.95% (E. coli O157:H7) and 84.90% (S. aureus) reduction in comparison to hydrophobic nonporous silica. These results suggest that the use of HNSA as surfaces that come into contact with bacterial pathogens in the healthcare environment can improve bacterial hygiene, and therefore may reduce the rate of HAIs.

Targeting Integrin-Dependent Adhesion and Signaling with 3-Arylquinoline and 3-Aryl-2-Quinolone Derivatives: A new Class of Integrin Antagonists

PubMed Central

Fiorucci, Sandrine; Lin, Xiaochen; Sadoul, Karin; Fournet, Guy; Bouvard, Daniel; Vinogradova, Olga; Joseph, Benoît; Block, Marc R.

2015-01-01

We previously reported the anti-migratory function of 3-aryl-2-quinolone derivatives, chemically close to flavonoids (Joseph et al., 2002). Herein we show that 3-arylquinoline or 3-aryl-2-quinolone derivatives disrupt cell adhesion in a dose dependent and reversible manner yet antagonized by artificial integrin activation such as manganese. Relying on this anti-adhesive activity, a Structure-Activity Relationship (SAR) study was established on 20 different compounds to throw the bases of future optimization strategies. Active drugs efficiently inhibit platelet spreading, aggregation, and clot retraction, processes that rely on αllbβ3 integrin activation and clustering. In vitro these derivatives interfere with β3 cytoplasmic tail interaction with kindlin-2 in pulldown assays albeit little effect was observed with pure proteins suggesting that the drugs may block an alternative integrin activation process that may not be directly related to kindlin recruitment. Ex vivo, these drugs blunt integrin signaling assayed using focal adhesion kinase auto-phosphorylation as a read-out. Hence, 3-arylquinoline and 3-aryl-2-quinolone series are a novel class of integrin activation and signaling antagonists. PMID:26509443

Biogenic nanosilver synthesized in Metarhizium robertsii waste mycelium extract – As a modulator of Candida albicans morphogenesis, membrane lipidome and biofilm

PubMed Central

Budzyńska, Aleksandra; Bernat, Przemysław

2018-01-01

Due to low efficacy of classic antimicrobial drugs, finding new active preparations attracts much attention. In this study an innovative, cost-effective and environmentally friendly method was applied to produce silver nanoparticles (AgNPs) using filamentous fungi Metarhizium robertsii biomass waste. It was shown that these NPs possess prominent antifungal effects against C. albicans, C. glabrata and C. parapsilosis reference strains. Further detailed studies were performed on C. albicans ATCC 90028. AgNPs kill curve (CFU method and esterase-mediated reduction of fluorescein diacetate); fractionally inhibitory concentration index (FICI) with fluconazole (FLC); effect on fungal cell membrane permeability (propidium iodide (PI) staining), membrane lipids profile (HPLC-MS), yeast morphotypes and intracellular reactive oxygen species level (H2DCFDA probe) were investigated. Anti-adhesive and anti-biofilm properties of AgNPs (alone and in combination with FLC) were also tested. Biosafety of AgNPs use was assessed in vitro in cytotoxicity tests against L929 fibroblasts, pulmonary epithelial A549 cell line, and red blood cells. Significant reduction in the viability of yeast cells treated with AgNPs was shown within 6 h. The proportion of C. albicans PI-positive cells increased in a dose and time-dependent manner. Changes in the qualitative and quantitative profile of cell membrane lipids, including significant decline in the quantity of most phospholipid species containing C18:2 and an increase in the amount of phospholipids containing C18:1 acyl species were observed after yeast exposure to AgNPs. CLSM images showed an enhancement in ROS intracellular accumulation in C. albicans treated with biogenic nanosilver. C. albicans transformation from yeast to hyphal forms was also reduced. AgNPs decreased adhesion of yeast to abiotic surfaces, as well as acted synergistically with FLC against sessile population. At fungicidal and fungistatic concentrations, they were non-toxic to mammalian cells. Obtained results confirm suitability of our “green synthesis” method to produce AgNPs with therapeutic potential against fungal infections. PMID:29554119

A pre-therapeutic coating for medical devices that prevents the attachment of Candida albicans.

PubMed

Vargas-Blanco, Diego; Lynn, Aung; Rosch, Jonah; Noreldin, Rony; Salerni, Anthony; Lambert, Christopher; Rao, Reeta P

2017-05-19

Hospital acquired fungal infections are defined as "never events"-medical errors that should never have happened. Systemic Candida albicans infections results in 30-50% mortality rates. Typically, adhesion to abiotic medical devices and implants initiates such infections. Efficient adhesion initiates formation of aggressive biofilms that are difficult to treat. Therefore, inhibitors of adhesion are important for drug development and likely to have a broad spectrum efficacy against many fungal pathogens. In this study we further the development of a small molecule, Filastatin, capable of preventing C. albicans adhesion. We explored the potential of Filastatin as a pre-therapeutic coating of a diverse range of biomaterials. Filastatin was applied on various biomaterials, specifically bioactive glass (cochlear implants, subcutaneous drug delivery devices and prosthetics); silicone (catheters and other implanted devices) and dental resin (dentures and dental implants). Adhesion to biomaterials was evaluated by direct visualization of wild type C. albicans or a non-adherent mutant edt1 -/- that were stained or fluorescently tagged. Strains grown overnight at 30 °C were harvested, allowed to attach to surfaces for 4 h and washed prior to visualization. The adhesion force of C. albicans cells attached to surfaces treated with Filastatin was measured using Atomic Force Microscopy. Effectiveness of Filastatin was also demonstrated under dynamic conditions using a flow cell bioreactor. The effect of Filastatin under microfluidic flow conditions was quantified using electrochemical impedance spectroscopy. Experiments were typically performed in triplicate. Treatment with Filastatin significantly inhibited the ability of C. albicans to adhere to bioactive glass (by 99.06%), silicone (by 77.27%), and dental resin (by 60.43%). Atomic force microcopy indicated that treatment with Filastatin decreased the adhesion force of C. albicans from 0.23 to 0.017 nN. Electrochemical Impedance Spectroscopy in a microfluidic device that mimic physiological flow conditions in vivo showed lower impedance for C. albicans when treated with Filastatin as compared to untreated control cells, suggesting decreased attachment. The anti-adhesive properties were maintained when Filastatin was included in the preparation of silicone materials. We demonstrate that Filastatin treated medical devices prevented adhesion of Candida, thereby reducing nosocomial infections.

NCAM polysialylation during adherence transitions: live cell monitoring using an antibody-mimetic EGFP-endosialidase and the viability dye DRAQ7.

PubMed

Smith, Paul J; Furon, Emeline; Wiltshire, Marie; Chappell, Sally; Patterson, Laurence H; Shnyder, Steven D; Falconer, Robert A; Errington, Rachel J

2013-07-01

Polysialylation of neural cell adhesion molecule (NCAM) in small-cell lung cancer (SCLC) is thought to regulate NCAM-mediated cell-surface interactions, imparting antiadhesive properties to cells. However, SCLC cells in culture demonstrate anchorage-independent growth and spontaneously generate adherent forms. Here, the ability of polySia-NCAM to influence cell proliferation and adherence is unclear. We analyzed live SCLC cell polySia-NCAM expression by flow cytometry, using the novel combination of a polySia antibody-mimetic eGFP-tagged endosialidase and the viability dye DRAQ7. Enrichment for adherence (<30 population doublings) in SCLC cell lines resolved populations with increased (SHP-77 and COR-L279) or negligible (NCI-H69) polysialylation compared with nonadherent parent populations. Adherent forms retained NCAM expression as confirmed by immunofluorescence and immunoblotting. Initial transition to adherence and loss of polysialylation in NCI-H69 was linked to a reduced proliferation rate with no increase in cell death. This reduced proliferation rate was reiterated in vivo as determined by the growth of noninvasive subcutaneous xenografts in mice. Continued selection for enhanced substrate adherence in NCI-H69 (>150 population doublings) resolved cells with stable re-expression of polySia and increased growth rates both in vitro and in vivo. Endoneuraminidase removal of polySia from re-expressing cells showed that rapid adherence to extracellular matrix components was functionally independent of polySia. PolySia expression was not altered when isolated adherent forms underwent enforced cell-cell contact in three-dimensional culture. Coculture of polySia expression variants modulated overall polySia expression profiles indicating an influence of SCLC microcommunity composition independent of substrate adherence potential. We conclude that an obligatory linkage between substrate adherence potential and polySia expression is rejected for SCLC cells. We suggest that a degree of homeostasis operates to regulate polysialylation within heterogeneous cell populations. The findings suggest a new model for SCLC progression while the application of live cell profiling of polysialylation could be used to assess polySia-NCAM-targeted therapies. Copyright © 2013 International Society for Advancement of Cytometry.

Single-cell force spectroscopy of the medically important Staphylococcus epidermidis-Candida albicans interaction

NASA Astrophysics Data System (ADS)

Beaussart, Audrey; Herman, Philippe; El-Kirat-Chatel, Sofiane; Lipke, Peter N.; Kucharíková, Soňa; van Dijck, Patrick; Dufrêne, Yves F.

2013-10-01

Despite the clinical importance of bacterial-fungal interactions, their molecular details are poorly understood. A hallmark of such medically important interspecies associations is the interaction between the two nosocomial pathogens Staphylococcus aureus and Candida albicans, which can lead to mixed biofilm-associated infections with enhanced antibiotic resistance. Here, we use single-cell force spectroscopy (SCFS) to quantify the forces engaged in bacterial-fungal co-adhesion, focusing on the poorly investigated S. epidermidis-C. albicans interaction. Force curves recorded between single bacterial and fungal germ tubes showed large adhesion forces (~5 nN) with extended rupture lengths (up to 500 nm). By contrast, bacteria poorly adhered to yeast cells, emphasizing the important role of the yeast-to-hyphae transition in mediating adhesion to bacterial cells. Analysis of mutant strains altered in cell wall composition allowed us to distinguish the main fungal components involved in adhesion, i.e. Als proteins and O-mannosylations. We suggest that the measured co-adhesion forces are involved in the formation of mixed biofilms, thus possibly as well in promoting polymicrobial infections. In the future, we anticipate that this SCFS platform will be used in nanomedicine to decipher the molecular mechanisms of a wide variety of pathogen-pathogen interactions and may help in designing novel anti-adhesion agents.

Antimicrobial, antiadhesive and antibiofilm activity of an ethanolic, anthocyanin-rich blueberry extract purified by solid phase extraction.

PubMed

Silva, S; Costa, E M; Mendes, M; Morais, R M; Calhau, C; Pintado, M M

2016-09-01

The present work aimed to characterize the impact of an anthocyanin-rich blueberry extract upon the growth, adhesion and biofilm formation of several pathogens including some multiresistant bacteria. A group comprised of reference strains and clinical multiresistant isolates of Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis, Acinetobacter baumannii and Staphylococcus aureus, were used to screen for antimicrobial activity. Microbial growth was determined through the measurement of the optical density while adhesion and biofilm formation was determined using the standard crystal violet staining procedure. The results showed that, while blueberry extract was only effective in hindering the growth of Staph. aureus and E. coli, it was capable of significantly inhibiting biofilm formation and bacterial adhesion for all micro-organisms tested. The extract demonstrated a considerable potential as a natural, alternative antimicrobial capable of either interfering with microbial growth or hamper the adhesion to surfaces, with Staph. aureus proving to be the most susceptible micro-organism. The overall study demonstrates the potential of anthocyanin extracts as natural effective alternative antimicrobial agents. Additionally, the extract's capacity to reduce adhesion without reducing bacterial growth reduces the likeliness of resistance development while reducing the probability of infection. © 2016 The Society for Applied Microbiology.

UroPathogenic Escherichia coli (UPEC) Infections: Virulence Factors, Bladder Responses, Antibiotic, and Non-antibiotic Antimicrobial Strategies

PubMed Central

Terlizzi, Maria E.; Gribaudo, Giorgio; Maffei, Massimo E.

2017-01-01

Urinary tract infections (UTIs) are one of the most common pathological conditions in both community and hospital settings. It has been estimated that about 150 million people worldwide develop UTI each year, with high social costs in terms of hospitalizations and medical expenses. Among the common uropathogens associated to UTIs development, UroPathogenic Escherichia coli (UPEC) is the primary cause. UPEC strains possess a plethora of both structural (as fimbriae, pili, curli, flagella) and secreted (toxins, iron-acquisition systems) virulence factors that contribute to their capacity to cause disease, although the ability to adhere to host epithelial cells in the urinary tract represents the most important determinant of pathogenicity. On the opposite side, the bladder epithelium shows a multifaceted array of host defenses including the urine flow and the secretion of antimicrobial substances, which represent useful tools to counteract bacterial infections. The fascinating and intricate dynamics between these players determine a complex interaction system that needs to be revealed. This review will focus on the most relevant components of UPEC arsenal of pathogenicity together with the major host responses to infection, the current approved treatment and the emergence of resistant UPEC strains, the vaccine strategies, the natural antimicrobial compounds along with innovative anti-adhesive and prophylactic approaches to prevent UTIs. PMID:28861072

Superhydrophobic Blood-Repellent Surfaces.

PubMed

Jokinen, Ville; Kankuri, Esko; Hoshian, Sasha; Franssila, Sami; Ras, Robin H A

2018-06-01

Superhydrophobic surfaces repel water and, in some cases, other liquids as well. The repellency is caused by topographical features at the nano-/microscale and low surface energy. Blood is a challenging liquid to repel due to its high propensity for activation of intrinsic hemostatic mechanisms, induction of coagulation, and platelet activation upon contact with foreign surfaces. Imbalanced activation of coagulation drives thrombogenesis or formation of blood clots that can occlude the blood flow either on-site or further downstream as emboli, exposing tissues to ischemia and infarction. Blood-repellent superhydrophobic surfaces aim toward reducing the thrombogenicity of surfaces of blood-contacting devices and implants. Several mechanisms that lead to blood repellency are proposed, focusing mainly on platelet antiadhesion. Structured surfaces can: (i) reduce the effective area exposed to platelets, (ii) reduce the adhesion area available to individual platelets, (iii) cause hydrodynamic effects that reduce platelet adhesion, and (iv) reduce or alter protein adsorption in a way that is not conducive to thrombus formation. These mechanisms benefit from the superhydrophobic Cassie state, in which a thin layer of air is trapped between the solid surface and the liquid. The connections between water- and blood repellency are discussed and several recent examples of blood-repellent superhydrophobic surfaces are highlighted. © 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Robust Non-Wetting PTFE Surfaces by Femtosecond Laser Machining

PubMed Central

Liang, Fang; Lehr, Jorge; Danielczak, Lisa; Leask, Richard; Kietzig, Anne-Marie

2014-01-01

Nature shows many examples of surfaces with extraordinary wettability, which can often be associated with particular air-trapping surface patterns. Here, robust non-wetting surfaces have been created by femtosecond laser ablation of polytetrafluoroethylene (PTFE). The laser-created surface structure resembles a forest of entangled fibers, which support structural superhydrophobicity even when the surface chemistry is changed by gold coating. SEM analysis showed that the degree of entanglement of hairs and the depth of the forest pattern correlates positively with accumulated laser fluence and can thus be influenced by altering various laser process parameters. The resulting fibrous surfaces exhibit a tremendous decrease in wettability compared to smooth PTFE surfaces; droplets impacting the virgin or gold coated PTFE forest do not wet the surface but bounce off. Exploratory bioadhesion experiments showed that the surfaces are truly air-trapping and do not support cell adhesion. Therewith, the created surfaces successfully mimic biological surfaces such as insect wings with robust anti-wetting behavior and potential for antiadhesive applications. In addition, the fabrication can be carried out in one process step, and our results clearly show the insensitivity of the resulting non-wetting behavior to variations in the process parameters, both of which make it a strong candidate for industrial applications. PMID:25110862

Xylitol-supplemented nutrition enhances bacterial killing and prolongs survival of rats in experimental pneumococcal sepsis

PubMed Central

Renko, Marjo; Valkonen, Päivi; Tapiainen, Terhi; Kontiokari, Tero; Mattila, Pauli; Knuuttila, Matti; Svanberg, Martti; Leinonen, Maija; Karttunen, Riitta; Uhari, Matti

2008-01-01

Background Xylitol has antiadhesive effects on Streptococcus pneumoniae and inhibits its growth, and has also been found to be effective in preventing acute otitis media and has been used in intensive care as a valuable source of energy. Results We evaluated the oxidative burst of neutrophils in rats fed with and without xylitol. The mean increase in the percentage of activated neutrophils from the baseline was higher in the xylitol-exposed group than in the control group (58.1% vs 51.4%, P = 0.03 for the difference) and the mean induced increase in the median strength of the burst per neutrophil was similarly higher in the xylitol group (159.6 vs 140.3, P = 0.04). In two pneumococcal sepsis experiments rats were fed either a basal powder diet (control group) or the same diet supplemented with 10% or 20% xylitol and infected with an intraperitoneal inoculation of S. pneumoniae after two weeks. The mean survival time was 48 hours in the xylitol groups and 34 hours in the control groups (P < 0.001 in log rank test). Conclusion Xylitol has beneficial effects on both the oxidative killing of bacteria in neutrophilic leucocytes and on the survival of rats with experimental pneumococcal sepsis. PMID:18334022

Human Milk Oligosaccharides (HMOS): Structure, Function, and Enzyme-Catalyzed Synthesis.

PubMed

Chen, Xi

2015-01-01

The important roles played by human milk oligosaccharides (HMOS), the third major component of human milk, in the health of breast-fed infants have been increasingly recognized, as the structures of more than 100 different HMOS have now been elucidated. Despite the recognition of the various functions of HMOS as prebiotics, antiadhesive antimicrobials, and immunomodulators, the roles and the applications of individual HMOS species are less clear. This is mainly due to the limited accessibility to large amounts of individual HMOS in their pure forms. Current advances in the development of enzymatic, chemoenzymatic, whole-cell, and living-cell systems allow for the production of a growing number of HMOS in increasing amounts. This effort will greatly facilitate the elucidation of the important roles of HMOS and allow exploration into the applications of HMOS both as individual compounds and as mixtures of defined structures with desired functions. The structures, functions, and enzyme-catalyzed synthesis of HMOS are briefly surveyed to provide a general picture about the current progress on these aspects. Future efforts should be devoted to elucidating the structures of more complex HMOS, synthesizing more complex HMOS including those with branched structures, and developing HMOS-based or HMOS-inspired prebiotics, additives, and therapeutics. © 2015 Elsevier Inc. All rights reserved.

Precision glass molding of high-resolution diffractive optical elements

NASA Astrophysics Data System (ADS)

Prater, Karin; Dukwen, Julia; Scharf, Toralf; Herzig, Hans P.; Plöger, Sven; Hermerschmidt, Andreas

2016-04-01

The demand of high resolution diffractive optical elements (DOE) is growing. Smaller critical dimensions allow higher deflection angles and can fulfill more demanding requirements, which can only be met by using electron-beam lithography. Replication techniques are more economical, since the high cost of the master can be distributed among a larger number of replicas. The lack of a suitable mold material for precision glass molding has so far prevented an industrial use. Glassy Carbon (GC) offers a high mechanical strength and high thermal strength. No anti-adhesion coatings are required in molding processes. This is clearly an advantage for high resolution, high aspect ratio microstructures, where a coating with a thickness between 10 nm and 200 nm would cause a noticeable rounding of the features. Electron-beam lithography was used to fabricate GC molds with highest precision and feature sizes from 250 nm to 2 μm. The master stamps were used for precision glass molding of a low Tg glass L-BAL42 from OHARA. The profile of the replicated glass is compared to the mold with the help of SEM images. This allows discussion of the max. aspect-ratio and min. feature size. To characterize optical performances, beamsplitting elements are fabricated and their characteristics were investigated, which are in excellent agreement to theory.

Oil adsorption ability of three-dimensional epicuticular wax coverages in plants

NASA Astrophysics Data System (ADS)

Gorb, Elena V.; Hofmann, Philipp; Filippov, Alexander E.; Gorb, Stanislav N.

2017-04-01

Primary aerial surfaces of terrestrial plants are very often covered with three-dimensional epicuticular waxes. Such wax coverages play an important role in insect-plant interactions. Wax blooms have been experimentally shown in numerous previous studies to be impeding locomotion and reducing attachment of insects. Among the mechanisms responsible for these effects, a possible adsorption of insect adhesive fluid by highly porous wax coverage has been proposed (adsorption hypothesis). Recently, a great decrease in insect attachment force on artificial adsorbing materials was revealed in a few studies. However, adsorption ability of plant wax blooms was still not tested. Using a cryo scanning electron microscopy approach and high-speed video recordings of fluid drops behavior, followed by numerical analysis of experimental data, we show here that the three-dimensional epicuticular wax coverage in the waxy zone of Nepenthes alata pitcher adsorbs oil: we detected changes in the base, height, and volume of the oil drops. The wax layer thickness, differing in samples with untreated two-layered wax coverage and treated one-layered wax, did not significantly affect the drop behavior. These results provide strong evidence that three-dimensional plant wax coverages due to their adsorption capability are in general anti-adhesive for insects, which rely on wet adhesion.

Protopine inhibits heterotypic cell adhesion in MDA-MB-231 cells through down-regulation of multi-adhesive factors.

PubMed

He, Kai; Gao, Jian-Li

2014-01-01

A Chinese herb Corydalis yanhusuo W.T. Wang that showed anticancer and anti-angiogenesis effects in our previous studies was presented for further studies. In the present study, we studied the anticancer proliferation and adhesion effects of five alkaloids which were isolated from Corydalis yanhusuo. MTT dose response curves, cell migration assay, cell invasion assay, as well as three types of cell adhesive assay were performed on MDA-MB-231 human breast cancer cells. The mechanism of the compounds on inhibiting heterotypic cell adhesion were further explored by determining the expression of epidermal growth factor receptor (EGFR), Intercellular adhesion molecule 1 (ICAM-1), αv-integrin, β1-integrin and β5-integrin by western blotting assay. In five tested alkaloids, only protopine exhibited anti-adhesive and anti-invasion effects in MDA-MB-231 cells, which contributed to the anti-metastasis effect of Corydalis yanhusuo. The results showed that after treatment with protopine for 90 min, the expression of EGFR, ICAM-1, αv-integrin, β1-integrin and β5-integrin were remarkably reduced. The present results suggest that protopine seems to inhibit the heterotypic cell adhesion between MDA-MB-231 cells, and human umbilical vein endothelial cells by changing the expression of adhesive factors.

Biomimetic multifunctional surfaces inspired from animals.

PubMed

Han, Zhiwu; Mu, Zhengzhi; Yin, Wei; Li, Wen; Niu, Shichao; Zhang, Junqiu; Ren, Luquan

2016-08-01

Over millions of years, animals have evolved to a higher intelligent level for their environment. A large number of diverse surface structures on their bodies have been formed to adapt to the extremely harsh environment. Just like the structural diversity existed in plants, the same also applies true in animals. Firstly, this article provides an overview and discussion of the most common functional surface structures inspired from animals, such as drag reduction, noise reduction, anti-adhesion, anti-wear, anti-erosion, anti-fog, water capture, and optical surfaces. Then, some typical characteristics of morphologies, structures, and materials of the animal multifunctional surfaces were discussed. The adaptation of these surfaces to environmental conditions was also analyzed. It mainly focuses on the relationship between their surface functions and their surface structural characteristics. Afterwards, the multifunctional mechanisms or principles of these surfaces were discussed. Models of these structures were provided for the development of structure materials and machinery surfaces. At last, fabrication techniques and existing or potential technical applications inspired from biomimetic multifunctional surfaces in animals were also discussed. The application prospects of the biomimetic functional surfaces are very broad, such as civil field of self-cleaning textile fabrics and non-stick pots, ocean field of oil-water separation, sports field of swimming suits, space development field of lens arrays. Copyright © 2016 Elsevier B.V. All rights reserved.

A Polymethyl Methacrylate-Based Acrylic Dental Resin Surface Bound with a Photoreactive Polymer Inhibits Accumulation of Bacterial Plaque.

PubMed

Fukunishi, Miya; Inoue, Yuuki; Morisaki, Hirobumi; Kuwata, Hirotaka; Ishihara, Kazuhiko; Baba, Kazuyoshi

The aim of this study was to examine the ability of a poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butylmethacrylate-co-2-methacryloyloxyethyloxy-p-azidobenzoate) (PMBPAz) coating on polymethyl methacrylate (PMMA)-based dental resin to inhibit bacterial plaque formation, as well as the polymer's durability against water soaking and chemical exposure. Successful application of PMBPAz on PMMA surfaces was confirmed by x-ray photoelectron spectroscopy (XPS) and measuring the static air contact angle in water. The anti-adhesive effects to bacterial plaque were evaluated using Streptococcus mutans biofilm formation assay. The mechanical and chemical durabilities of the PMBPAz coating on the PMMA surfaces were examined using soaking and immersion tests, respectively. XPS signals for phosphorus and nitrogen atoms and hydrophilic status on PMMA surfaces treated with PMBPAz were observed, indicating the presence of the polymer on the substrates. The treated PMMA surfaces showed significant inhibition of S mutans biofilm formation compared to untreated surfaces. The PMBPAz coating was preserved after water soaking and chemical exposure. In addition, water soaking did not decrease the ability of treated PMMA to inhibit biofilm formation compared to treated PMMA specimens not subjected to water soaking. This study suggests that PMBPAz coating may represent a useful modification to PMMA surfaces for inhibiting denture plaque accumulation.

Synergistic Activity of Dispersin B and Cefamandole Nafate in Inhibition of Staphylococcal Biofilm Growth on Polyurethanes▿

PubMed Central

Donelli, G.; Francolini, I.; Romoli, D.; Guaglianone, E.; Piozzi, A.; Ragunath, C.; Kaplan, J. B.

2007-01-01

Antibiotic therapies to eradicate medical device-associated infections often fail because of the ability of sessile bacteria, encased in their exopolysaccharide matrix, to be more drug resistant than planktonic organisms. In the last two decades, several strategies to prevent microbial adhesion and biofilm formation on the surfaces of medical devices, based mainly on the use of antiadhesive, antiseptic, and antibiotic coatings on polymer surfaces, have been developed. More recent alternative approaches are based on molecules able to interfere with quorum-sensing phenomena or to dissolve biofilms. Interestingly, a newly purified β-N-acetylglucosaminidase, dispersin B, produced by the gram-negative periodontal pathogen Actinobacillus actinomycetemcomitans, is able to dissolve mature biofilms produced by Staphylococcus epidermidis as well as some other bacterial species. Therefore, in this study, we developed new polymeric matrices able to bind dispersin B either alone or in combination with an antibiotic molecule, cefamandole nafate (CEF). We showed that our functionalized polyurethanes could adsorb a significant amount of dispersin B, which was able to exert its hydrolytic activity against the exopolysaccharide matrix produced by staphylococcal strains. When microbial biofilms were exposed to both dispersin B and CEF, a synergistic action became evident, thus characterizing these polymer-dispersin B-antibiotic systems as promising, highly effective tools for preventing bacterial colonization of medical devices. PMID:17548491

Accessibility and contribution to glucan masking of natural and genetically tagged versions of yeast wall protein 1 of Candida albicans

PubMed Central

2018-01-01

Yeast wall protein 1 (Ywp1) is an abundant glycoprotein of the cell wall of the yeast form of Candida albicans, the most prevalent fungal pathogen of humans. Antibodies that bind to the polypeptide backbone of isolated Ywp1 show little binding to intact yeast cells, presumably because the Ywp1 epitopes are masked by the polysaccharides of the mannoproteins that form the outer layer of the cell wall. Rare cells do exhibit much greater anti-Ywp1 binding, however, and one of these was isolated and characterized. No differences were seen in its Ywp1, but it exhibited greater adhesiveness, sensitivity to wall perturbing agents, and exposure of its underlying β-1,3-glucan layer to external antibodies. The molecular basis for this greater epitope accessibility has not been determined, but has facilitated exploration of how these properties change as a function of cell growth and morphology. In addition, previously engineered strains with reduced quantities of Ywp1 in their cell walls were also found to have greater β-1,3-glucan exposure, indicating that Ywp1 itself contributes to the masking of wall epitopes, which may be important for understanding the anti-adhesive effect of Ywp1. Ectopic production of Ywp1 by hyphae, which reduces the adhesivity of these filamentous forms of C. albicans, was similarly found to reduce exposure of the β-1,3-glucan in their walls. To monitor Ywp1 in the cell wall irrespective of its accessibility, green fluorescent protein (Gfp) was genetically inserted into wall-anchored Ywp1 using a bifunctional cassette that also allowed production from a single transfection of a soluble, anchor-free version. The wall-anchored Ywp1-Gfp-Ywp1 accumulated in the wall of the yeast forms but not hyphae, and appeared to have properties similar to native Ywp1, including its adhesion-inhibiting effect. Some pseudohyphal walls also detectably accumulated this probe. Strains of C. albicans with tandem hemagglutinin (HA) epitopes inserted into wall-anchored Ywp1 were previously created by others, and were further explored here. As above, rare cells with much greater accessibility of the HA epitopes were isolated, and also found to exhibit greater exposure of Ywp1 and β-1,3-glucan. The placement of the HA cassette inhibited the normal N-glycosylation and propeptide cleavage of Ywp1, but the wall-anchored Ywp1-HA-Ywp1 still accumulated in the cell wall of yeast forms. Bifunctional transformation cassettes were used to additionally tag these molecules with Gfp, generating soluble Ywp1-HA-Gfp and wall-anchored Ywp1-HA-Gfp-Ywp1 molecules. The former revealed unexpected electrophoretic properties caused by the HA insertion, while the latter further highlighted differences between the presence of a tagged Ywp1 molecule (as revealed by Gfp fluorescence) and its accessibility in the cell wall to externally applied antibodies specific for HA, Gfp and Ywp1, with accessibility being greatest in the rapidly expanding walls of budding daughter cells. These strains and results increase our understanding of cell wall properties and how C. albicans masks itself from recognition by the human immune system. PMID:29329339

Accessibility and contribution to glucan masking of natural and genetically tagged versions of yeast wall protein 1 of Candida albicans.

PubMed

Granger, Bruce L

2018-01-01

Yeast wall protein 1 (Ywp1) is an abundant glycoprotein of the cell wall of the yeast form of Candida albicans, the most prevalent fungal pathogen of humans. Antibodies that bind to the polypeptide backbone of isolated Ywp1 show little binding to intact yeast cells, presumably because the Ywp1 epitopes are masked by the polysaccharides of the mannoproteins that form the outer layer of the cell wall. Rare cells do exhibit much greater anti-Ywp1 binding, however, and one of these was isolated and characterized. No differences were seen in its Ywp1, but it exhibited greater adhesiveness, sensitivity to wall perturbing agents, and exposure of its underlying β-1,3-glucan layer to external antibodies. The molecular basis for this greater epitope accessibility has not been determined, but has facilitated exploration of how these properties change as a function of cell growth and morphology. In addition, previously engineered strains with reduced quantities of Ywp1 in their cell walls were also found to have greater β-1,3-glucan exposure, indicating that Ywp1 itself contributes to the masking of wall epitopes, which may be important for understanding the anti-adhesive effect of Ywp1. Ectopic production of Ywp1 by hyphae, which reduces the adhesivity of these filamentous forms of C. albicans, was similarly found to reduce exposure of the β-1,3-glucan in their walls. To monitor Ywp1 in the cell wall irrespective of its accessibility, green fluorescent protein (Gfp) was genetically inserted into wall-anchored Ywp1 using a bifunctional cassette that also allowed production from a single transfection of a soluble, anchor-free version. The wall-anchored Ywp1-Gfp-Ywp1 accumulated in the wall of the yeast forms but not hyphae, and appeared to have properties similar to native Ywp1, including its adhesion-inhibiting effect. Some pseudohyphal walls also detectably accumulated this probe. Strains of C. albicans with tandem hemagglutinin (HA) epitopes inserted into wall-anchored Ywp1 were previously created by others, and were further explored here. As above, rare cells with much greater accessibility of the HA epitopes were isolated, and also found to exhibit greater exposure of Ywp1 and β-1,3-glucan. The placement of the HA cassette inhibited the normal N-glycosylation and propeptide cleavage of Ywp1, but the wall-anchored Ywp1-HA-Ywp1 still accumulated in the cell wall of yeast forms. Bifunctional transformation cassettes were used to additionally tag these molecules with Gfp, generating soluble Ywp1-HA-Gfp and wall-anchored Ywp1-HA-Gfp-Ywp1 molecules. The former revealed unexpected electrophoretic properties caused by the HA insertion, while the latter further highlighted differences between the presence of a tagged Ywp1 molecule (as revealed by Gfp fluorescence) and its accessibility in the cell wall to externally applied antibodies specific for HA, Gfp and Ywp1, with accessibility being greatest in the rapidly expanding walls of budding daughter cells. These strains and results increase our understanding of cell wall properties and how C. albicans masks itself from recognition by the human immune system.

A bioinspired approach to the generation of novel antimicrobial materials

NASA Astrophysics Data System (ADS)

Nowlin, Kyle S.

Advancements in particle beam microscopy have allowed scientists to discover a wealth of surface architectures with nanoscale dimensions, many of which endow the surfaces with fascinating properties. Investigations of such surfaces have revealed some exciting physical phenomena, ranging from complex interactions with light such as brilliant iridescent colors resulting from diffraction and interference to water repelling self-cleaning superhydrophobic surfaces. Interestingly, the biological world, especially that of insects, has perhaps contributed the greatest number of these discoveries and will likely continue to do so as long as scientists entertain the idea that nature still has a vast collection of lessons to teach us. Examples of such phenomena include the structurally derived colors displayed by Chrysiridia rhipheus (Madagascan sunset moth), the anti-reflective and self-cleaning wings of Psaltoda claripennis (Clanger cicada), along with its more recent discovery of mechanically induced bactericidal activity. The implications of such a discovery are truly revolutionary as it is the first time that surface topography has been linked to microbial death. With this discovery a new defensive strategy against biofilm derived pathogenesis and related problems has arrived and must be further investigated for a more thorough understanding. It's a generally accepted notion that fungi much like bacteria can form complex protective biofilms and are undoubtedly a source of pathogenesis. For example C. albicans is the fourth most frequent organism found in the blood of hospitalized patients. While bacterial infections have been given much attention, less has been given to fungal biofilms though they are a major source of nosocomial infections attributed in part to adhesion to invasive devices such as catheters, cardiac pacemakers, prosthetic heart valves etc. S. cerevisiae, a generally non-pathogenic yeast, has been proposed as a model for fungal biofilm formation with similar behaviors but far more genetic tools available. In the present work I investigate the effects that the nano-structured wings of our local Dog Day cicada Tibicen tibicen have on adhered S. cerevisiae to assess for antifungal activity. Resembling that of the bactericidal activity, my study concludes antifungal activity of a cell rupturing mechanical nature attributed to the nano-topography of the Dog Day cicada wing. Following this discovery I utilize nano-sphere lithography (NSL) to fabricate analogous nanostructures as well as proportionally smaller and larger nanostructures in common synthetic polymers to be tested for translation of function. Studies with E. coli and S. cerevisiae reveal the overlooked but fundamentally important mechanical properties of nano-structures as they apply to mechanical microbicidal functionality. In addition to biocidal activity studies, I also demonstrate the remarkable anti-adhesive nature of a particular scale nano-patterned surface relative to flat surfaces of analogous chemistry.

Interaction of Poly(l-lysine)/Polysaccharide Complex Nanoparticles with Human Vascular Endothelial Cells.

PubMed

Weber, Dominik; Torger, Bernhard; Richter, Karsten; Nessling, Michelle; Momburg, Frank; Woltmann, Beatrice; Müller, Martin; Schwartz-Albiez, Reinhard

2018-05-23

Angiogenesis plays an important role in both soft and hard tissue regeneration, which can be modulated by therapeutic drugs. If nanoparticles (NP) are used as vectors for drug delivery, they have to encounter endothelial cells (EC) lining the vascular lumen, if applied intravenously. Herein the interaction of unloaded polyelectrolyte complex nanoparticles (PECNP) composed of cationic poly(l-lysine) (PLL) and various anionic polysaccharides with human vascular endothelial cells (HUVEC) was analyzed. In particular PECNP were tested for their cell adhesive properties, their cellular uptake and intracellular localization considering composition and net charge. PECNP may form a platform for both cell coating and drug delivery. PECNP, composed of PLL in combination with the polysaccharides dextran sulfate (DS), cellulose sulfate (CS) or heparin (HEP), either unlabeled or labeled with fluorescein isothiocyanate (FITC) and either with positive or negative net charge were prepared. PECNP were applied to human umbilical cord vein endothelial cells (HUVEC) in both, the volume phase and immobilized phase at model substrates like tissue culture dishes. The attachment of PECNP to the cell surface, their intracellular uptake, and effects on cell proliferation and growth behavior were determined. Immobilized PECNP reduced attachment of HUVEC, most prominently the systems PLL/HEP and PLL/DS. A small percentage of immobilized PECNP was taken up by cells during adhesion. PECNP in the volume phase showed no effect of the net charge sign and only minor effects of the composition on the binding and uptake of PECNP at HUVEC. PECNP were stored in endosomal vesicles in a cumulative manner without apparent further processing. During mitosis, internalized PECNP were almost equally distributed among the dividing cells. Both, in the volume phase and immobilized at the surface, PECNP composed of PLL/HEP and PLL/DS clearly reduced cell proliferation of HUVEC, however without an apparent cytotoxic effect, while PLL/CS composition showed minor impairment. PECNP have an anti-adhesive effect on HUVEC and are taken up by endothelial cells which may negatively influence the proliferation rate of HUVEC. The negative effects were less obvious with the composition PLL/CS. Since uptake and binding for PLL/HEP was more efficient than for PLL/DS, PECNP of PLL/HEP may be used to deliver growth factors to endothelial cells during vascularization of bone reconstitution material, whereas those of PLL/CS may have an advantage for substituting biomimetic bone scaffold material.

Thermo-responsive in-situ forming hydrogels as barriers to prevent post-operative peritendinous adhesion.

PubMed

Chou, Pang-Yun; Chen, Shih-Heng; Chen, Chih-Hao; Chen, Shih-Hsien; Fong, Yi Teng; Chen, Jyh-Ping

2017-11-01

In this study, we aimed to assess whether thermo-responsive in-situ forming hydrogels based on poly(N-isopropylacrylamide) (PNIPAM) could prevent post-operative peritendinous adhesion. The clinical advantages of the thermo-responsive hydrogels are acting as barrier material to block penetration of fibroblasts, providing mobility and flexibility during application and enabling injection through a small opening to fill spaces of any shape after surgery. The thermo-responsiveness of hydrogels was determined to ensure their clinic uses. By grafting hydrophilic biopolymers chitosan (CS) and hyaluronic acid (HA) to PNIPAM, the copolymer hydrogels show enhanced water retention and lubrication, while reduced volume shrinkage during phase transition. In cell culture experiments, the thermo-responsive hydrogel has good biocompatibility and reduces fibroblast penetration. In animal experiments, the effectiveness of preventing post-operative peritendinous adhesion was studied in a rabbit deep flexor tendon model. From gross examination, histology, bending angles of joints, tendon gliding excursion and pull-out force, HA-CS-PNIPAM (HACPN) was confirmed to be the best barrier material to prevent post-operative peritendinous adhesion compared to PNIPAM and CS-PNIPAM (CPN) hydrogels and a commercial barrier film Seprafilm®. There was no significant difference in the breaking strength of HACPN-treated tendons and spontaneously healed ones, indicating HACPN hydrogel application did not interfere with normal tendon healing. We conclude that HACPN hydrogel can provide the best functional outcomes to significantly prevent post-operative tendon adhesion in vivo. We prepared thermo-responsive in-situ forming hydrogels based on poly(N-isopropylacrylamide) (PNIPAM) to prevent post-operative peritendinous adhesion. The injectable barrier hydrogel could have better anti-adhesive properties than current commercial products by acting as barrier material to block penetration of fibroblasts, providing mobility and flexibility during application and enabling injection through a small opening to fill spaces of any shape after surgery. The effectiveness of preventing post-operative peritendinous adhesion was studied in a rabbit deep flexor tendon model. From gross examination, histology, bending angles of joints, tendon gliding excursion and pull-out force, HA-CS-PNIPAM (HACPN) was confirmed to be the best barrier material to prevent post-operative peritendinous adhesion compared to PNIPAM and CS-PNIPAM (CPN) hydrogels and a commercial barrier film Seprafilm®. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Tissue response to five commercially available peritoneal adhesion barriers-A systematic histological evaluation.

PubMed

Schmitt, Volker H; Mamilos, Andreas; Schmitt, Christine; Neitzer-Planck, Constanze N E; Rajab, Taufiek K; Hollemann, David; Wagner, Willi; Krämer, Bernhard; Hierlemann, Helmut; James Kirkpatrick, C; Brochhausen, Christoph

2018-02-01

Separating wounded serosa by physical barriers is the only clinically approved adjunct for postoperative adhesion prevention. Since the optimal adhesion barrier has not been found, it is essential to improve our pathogenic understanding of adhesion formation and to compare the effects of different barrier materials on tissue and cells. Wistar rats underwent standardized peritoneal damage and were treated either with Seprafilm, Adept, Intercoat, Spraygel, SupraSeal or remained untreated as a control. 14 days postoperatively, the lesions were explanted and histomorphologically analyzed using the European ISO score to evaluate material implants. Striking differences between the material groups were present regarding the inflammation, fibrosis, and foreign body reaction. According to the ISO score, Intercoat and Spraygel were considered as nonirritating to tissue. Adept, Seprafilm, and SupraSeal were assessed as mild-irritating materials. Interestingly, the most effective material in adhesion prevention revealed moderate inflammation accompanied by minor fibrosis. The degree of inflammation to barrier materials does not predict the efficacy in the prevention of adhesions. Histopathological investigations are crucial to improve our understanding of the cellular mechanisms during adhesion formation and elucidate the tissue response to material approaches used in adhesion prevention. This will lead to improved antiadhesive strategies and the development of functional barrier biomaterials. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 598-609, 2018. © 2017 Wiley Periodicals, Inc.

In vivo performance of melimine as an antimicrobial coating for contact lenses in models of CLARE and CLPU.

PubMed

Cole, Nerida; Hume, Emma B H; Vijay, Ajay K; Sankaridurg, Padmaja; Kumar, Naresh; Willcox, Mark D P

2010-01-01

One strategy to minimize bacteria-associated adverse responses such as microbial keratitis, contact lens-induced acute red eye (CLARE), and contact lens induced peripheral ulcers (CLPUs) that occur with contact lens wear is the development of an antimicrobial or antiadhesive contact lens. Cationic peptides represent a novel approach for the development of antimicrobial lenses. A novel cationic peptide, melimine, was covalently incorporated into silicone hydrogel lenses. Confirmation tests to determine the presence of peptide and anti-microbial activity were performed. Cationic lenses were then tested for their ability to prevent CLPU in the Staphylococcus aureus rabbit model and CLARE in the Pseudomonas aeruginosa guinea pig model. In the rabbit model of CLPU, melimine-coated lenses resulted in significant reductions in ocular symptom scores and in the extent of corneal infiltration (P < 0.05). Evaluation of the performance of melimine lenses in the CLARE model showed significant improvement in all ocular response parameters measured, including the percentage of eyes with corneal infiltrates, compared with those observed in the eyes fitted with the control lens (P < or = 0.05). Cationic coating of contact lenses with the peptide melimine may represent a novel method of prevention of bacterial growth on contact lenses and consequently result in reduction of the incidence and severity of adverse responses due to Gram-positive and -negative bacteria during lens wear.

Polyethyleneimine brushes effectively inhibit encrustation on polyurethane ureteral stents both in dynamic bioreactor and in vivo.

PubMed

Gultekinoglu, Merve; Kurum, Barış; Karahan, Siyami; Kart, Didem; Sagiroglu, Meral; Ertaş, Nusret; Haluk Ozen, A; Ulubayram, Kezban

2017-02-01

Polyurethane (PU) ureteral stents have been widely used as biomedical devices to aid the flow of the urine. Due to the biofilm formation and encrustation complications it has been hindered their long term clinical usage. To overcome these complications, in this study, cationic polyethyleneimine (PEI) brushes grafted on PU stents and their performances were tested both in a dynamic biofilm reactor system (in vitro) and in a rat model (in vivo). Thus, we hypothesized that PEI brushes inhibit bacterial adhesion owing to the dynamic motion of brushes in liquid environment. In addition, cationic structure of PEI disrupts the membrane and so kills the bacteria on time of contact. Cationic PEI brushes decreased the biofilm formation up to 2 orders of magnitude and approximately 50% of encrustation amount in respect to unmodified PU, in vitro. In addition, according to Atomic Absorption Spectroscopy (AAS) results, approximately 90% of encrustation was inhibited on in vivo animal models. Decrease in encrustation was clearly observed on the stents obtained from rat model, by Scanning Electron Microscopy (SEM). Also, histological evaluations showed that; PEI brush grafting decreased host tissue inflammation in close relation to decrease in biofilm formation and encrustation. As a results; dual effect of anti-adhesive and contact-killing antibacterial strategy showed high efficiency on PEI brushes grafted PU stents both in vitro and in vivo. Copyright © 2016 Elsevier B.V. All rights reserved.

An Experimental Implementation of Chemical Subtraction

PubMed Central

Chen, Shao-Nong; Turner, Allison; Jaki, Birgit U.; Nikolic, Dejan; van Breemen, Richard B.; Friesen, J. Brent; Pauli, Guido F.

2008-01-01

A preparative analytical method was developed to selectively remove (“chemically subtract”) a single compound from a complex mixture, such as a natural extract or fraction, in a single step. The proof of concept is demonstrated by the removal of pure benzoic acid (BA) from cranberry (Vaccinium macrocarpon Ait.) juice fractions that exhibit anti-adhesive effects vs. uropathogenic E. coli. Chemical subtraction of BA, representing a major constituent of the fractions, eliminates the potential in vitro interference of the bacteriostatic effect of BA on the E. coli anti-adherence action measured in bioassays. Upon BA removal, the anti-adherent activity of the fraction was fully retained, 36% inhibition of adherence in the parent fraction at 100 ug/mL increased to 58% in the BA-free active fraction. The method employs countercurrent chromatography (CCC) and operates loss-free for both the subtracted and the retained portions as only liquid-liquid partitioning is involved. While the high purity (97.47% by quantitative 1H NMR) of the subtracted BA confirms the selectivity of the method, one minor impurity was determined to be scopoletin by HR-ESI-MS and (q)HNMR and represents the first coumarin reported from cranberries. A general concept for the selective removal of phytoconstituents by CCC is presented, which has potential broad applicability in the biological evaluation of medicinal plant extracts and complex pharmaceutical preparations. PMID:18234463

Possible involvement of the transient receptor potential vanilloid type 1 channel in postoperative adhesive obstruction and its prevention by a kampo (traditional Japanese) medicine, daikenchuto.

PubMed

Tokita, Yohei; Yamamoto, Masahiro; Satoh, Kazuko; Nishiyama, Mitsue; Iizuka, Seiichi; Imamura, Sachiko; Kase, Yoshio

2011-01-01

This study focused on the localization of transient receptor potential vanilloid type 1 (TRPV1) in the intestines in postoperative adhesion model rats and investigated the underlying mechanism for the anti-adhesion action of daikenchuto (DKT), especially in relation to TRPV1. Postoperative intestinal adhesion was induced by sprinkling talc in the small intestine. The expression of TRPV1 mRNA was examined by in situ hybridization and real-time RT-PCR. The effects of DKT and its major ingredient, hydroxy sanshool, with or without ruthenium red, a TRP-channel antagonist, on talc-induced intestinal adhesions were evaluated. The level of TRPV1 mRNA was higher in the adhesion regions of talc-treated rats than in normal small intestine of sham-operated rats. Localization of TRPV1 mRNA expression was identified in the submucosal plexus of both sham-operated and talc-treated rats; and in talc-treated rats, it was observed also in the myenteric plexus and regions of adhesion. Capsaicin, DKT, and hydroxy sanshool significantly prevented formation of intestinal adhesions. The effects of DKT and hydroxy sanshool were abrogated by subcutaneous injection of ruthenium red. These results suggest that pharmacological modulation of TRPV1 might be a possible therapeutic option in postoperative intestinal adhesion, which might be relevant to the prevention of postoperative adhesive obstruction by DKT.

A rat hysteropexy model for evaluating adhesion formation and comparison of two different structured meshes.

PubMed

Gokmen-Karasu, Ayse Filiz; Aydin, Serdar; Sonmez, Fatma Cavide; Adanir, Ilknur; Ilhan, Gulsah; Ates, Seda

2017-11-01

Peritonization of mesh during sacrohysteropexy is generally advocated to prevent adhesions to the viscera; however, randomized clinical trials are lacking, and peritonization may not be completely possible in a laparoscopic hysteropexy procedure. Our main objective was to describe a basic experimental rat sacrohysteropexy model. We hypothesized that even when peritoneal closure was omitted, using composite mesh would result in less adhesions to the viscera. Twenty in-bred female virgin Wistar Hannover rats were used in this study. Standardized hysteropexy procedure and adhesion model is described step by step with two different mesh materials: polypropylene and a composite polyester. Mesh was anchored between the posterior cervix and anterior longitudinal ligament of the lumbar vertebrae. Macroscopic adhesion scores and histopathological tissue reaction was investigated. Macroscopically, the surface area involved in adhesions was similar between groups. However, adhesions in the polypropylene group were more dense, required sharp dissection for lysis, and yielded higher total macroscopic adhesion scores (p < 0.001). Histologically, a more pronounced host inflammatory response was encountered in the polyester group (p < 0.001). We describe a rat hysteropexy model and a previously established uterine adhesion model. Adhesion scores in the composite mesh group were lower, and bowel involvement was not seen. Our findings are promising, and further research investigating antiadhesive composite mesh use for hysterosacropexy would be appropriate, especially when peritoneal closure is omitted.

Mitigation of Biofilm Development on Thin-Film Composite Membranes Functionalized with Zwitterionic Polymers and Silver Nanoparticles.

PubMed

Liu, Caihong; Faria, Andreia F; Ma, Jun; Elimelech, Menachem

2017-01-03

We demonstrate the functionalization of thin-film composite membranes with zwitterionic polymers and silver nanoparticles (AgNPs) for combating biofouling. Combining hydrophilic zwitterionic polymer brushes and biocidal AgNPs endows the membrane with dual functionality: antiadhesion and bacterial inactivation. An atom transfer radical polymerization (ATRP) reaction is used to graft zwitterionic poly(sulfobetaine methacrylate) (PSBMA) brushes to the membrane surface, while AgNPs are synthesized in situ through chemical reduction of silver. Two different membrane architectures (Ag-PSBMA and PSBMA-Ag TFC) are developed according to the sequence AgNPs, and PSBMA brushes are grafted on the membrane surface. A static adhesion assay shows that both modified membranes significantly reduced the adsorption of proteins, which served as a model organic foulant. However, improved antimicrobial activity is observed for PSBMA-Ag TFC (i.e., AgNPs on top of the polymer brush) in comparison to the Ag-PSBMA TFC membrane (i.e., polymer brush on top of AgNPs), indicating that architecture of the antifouling layer is an important factor in the design of zwitterion-silver membranes. Confocal laser scanning microscopy (CLSM) imaging indicated that PSBMA-Ag TFC membranes effectively inhibit biofilm formation under dynamic cross-flow membrane biofouling tests. Finally, we demonstrate the regeneration of AgNPs on the membrane after depletion of silver from the surface of the PSBMA-Ag TFC membrane.

Antifouling coatings via plasma polymerization and atom transfer radical polymerization on thin film composite membranes for reverse osmosis

NASA Astrophysics Data System (ADS)

Hirsch, Ulrike; Ruehl, Marco; Teuscher, Nico; Heilmann, Andreas

2018-04-01

A major drawback to otherwise highly efficient membrane-based desalination techniques like reverse osmosis (RO) is the susceptibility of the membranes to biofouling. In this work, a combination of plasma activation, plasma bromination and surface-initiated atom transfer radical polymerization (si-ATRP) of hydrophilic and zwitterionic monomers, namely hydroxyethyl methacrylate (HEMA), 2-methacryloyloxyethyl phosphorylcholine (MPC) and [2-(methacryloyloxy)ethyl]-dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA), was applied to generate non-specific, anti-adhesive coatings on thin film composite (TFC) membranes. The antifouling effect of the coatings was shown by short-time batch as well as long-time steady state cultivation experiments with the microorganism Pseudomonas fluorescens. It could be shown that plasma functionalization and polymerization is possible on delicate thin film composite membranes without restricting their filtration performance. All modified membranes showed an increased resistance towards the adhesion of Pseudomonas fluorescens. On average, the biofilm coverage was reduced by 51.4-12.6% (for HEMA, SBMA, and MPC), the highest reduction was monitored for MPC with a biofilm reduction by 85.4%. The hydrophilic coatings applied did not only suppress the adhesion of Pseudomonas fluorescens, but also significantly increase the permeate flux of the membranes relative to uncoated membranes. The stability of the coatings was however not ideal and will have to be improved for future commercial use.

Cholera Toxin Inhibitors Studied with High-Performance Liquid Affinity Chromatography: A Robust Method to Evaluate Receptor–Ligand Interactions

PubMed Central

Bergström, Maria; Liu, Shuang; Kiick, Kristi L.; Ohlson, Sten

2009-01-01

Anti-adhesion drugs may be an alternative to antibiotics to control infection of micro-organisms. The well-characterized interaction between cholera toxin and the cellular glycolipid GM1 makes it an attractive model for inhibition studies in general. In this report, we demonstrate a high-performance liquid affinity chromatography approach called weak affinity chromatography to evaluate cholera toxin inhibitors. The cholera toxin B-subunit was covalently coupled to porous silica and a (weak) affinity column was produced. The KD values of galactose and meta-nitrophenyl α-D-galactoside were determined with weak affinity chromatography to be 52 and 1 mM, respectively, which agree well with IC50 values previously reported. To increase inhibition potency multivalent inhibitors have been developed and the interaction with multivalent glycopolypeptides was also evaluated. The affinity of these compounds was found to correlate with the galactoside content but KD values were not obtained because of the inhomogeneous response and slow off-rate from multivalent interactions. Despite the limitations in obtaining direct KD values of the multivalent galactopolypeptides, weak affinity chromatography represents an additional and valuable tool in the evaluation of monovalent as well as multivalent cholera toxin inhibitors. It offers multiple advantages, such as a low sample consumption, high reproducibility and short analysis time, which are often not observed in other methods of analysis. PMID:19152642

Trehalose does not affect the functions of human neutrophils in vitro.

PubMed

Tanaka, Koji; Kawamura, Mikio; Otake, Kohei; Toiyama, Yuji; Okugawa, Yoshinaga; Inoue, Yasuhiro; Uchida, Keiichi; Araki, Toshimitsu; Mohri, Yasuhiko; Kusunoki, Masato

2014-02-01

Trehalose, naturally occurring disaccharide, has been reported to prevent postoperative abdominal adhesions in animal models. We investigated whether trehalose affects the function of human polymorphonuclear neutrophils (PMNs) in vitro to assess the feasibility of its clinical application as an anti-adhesive barrier. Human PMNs were obtained from 17 healthy volunteers. Escherichia coli and Staphylococcus aureus were used for the bacterial infection model, whereas lipopolysaccharide (LPS) and interleukin (IL)-1β were used for inflammation induction model. The PMN phagocytosis rates of bacteria and apoptosis/necrosis were assessed on trehalose, maltose, and control media. Cytokines; namely, tumor necrosis factor-α, IL-1α, IL-1Ra, IL-6, and IL-8; and PMN-elastase were measured on each medium in both models. There were no significant differences in the phagocytosis rates, apoptosis/necrosis rates, or levels of all cytokines or PMN-elastase among the three media in the bacterial infection model. There were also no significant differences in the levels of all cytokines and PMN-elastase among the three media in the IL-1β inflammation induction model. PMN-elastase was lower in trehalose and maltose medium after LPS stimulation, at 3 and 24 h. Our results suggest that trehalose does not affect the cellular function, cytokine production, or release of PMN-elastase of human PMNs in an in vitro bacterial infection model.

Surface modifications for antimicrobial effects in the healthcare setting: a critical overview.

PubMed

Adlhart, C; Verran, J; Azevedo, N F; Olmez, H; Keinänen-Toivola, M M; Gouveia, I; Melo, L F; Crijns, F

2018-02-02

The spread of infections in healthcare environments is a persistent and growing problem in most countries, aggravated by the development of microbial resistance to antibiotics and disinfectants. In addition to indwelling medical devices (e.g. implants, catheters), such infections may also result from adhesion of microbes either to external solid-water interfaces such as shower caps, taps, drains, etc., or to external solid-gas interfaces such as door handles, clothes, curtains, computer keyboards, etc. The latter are the main focus of the present work, where an overview of antimicrobial coatings for such applications is presented. This review addresses well-established and novel methodologies, including chemical and physical functional modification of surfaces to reduce microbial contamination, as well as the potential risks associated with the implementation of such anticontamination measures. Different chemistry-based approaches are discussed, for instance anti-adhesive surfaces (e.g. superhydrophobic, zwitterions), contact-killing surfaces (e.g. polymer brushes, phages), and biocide-releasing surfaces (e.g. triggered release, quorum sensing-based systems). The review also assesses the impact of topographical modifications at distinct dimensions (micrometre and nanometre orders of magnitude) and the importance of applying safe-by-design criteria (e.g. toxicity, contribution for unwanted acquisition of antimicrobial resistance, long-term stability) when developing and implementing antimicrobial surfaces. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

The use of clamping grips and friction pads by tree frogs for climbing curved surfaces

PubMed Central

Ji, Aihong; Yuan, Shanshan; Hill, Iain; Wang, Huan; Barnes, W. Jon P.; Dai, Zhendong; Sitti, Metin

2017-01-01

Most studies on the adhesive mechanisms of climbing animals have addressed attachment against flat surfaces, yet many animals can climb highly curved surfaces, like twigs and small branches. Here we investigated whether tree frogs use a clamping grip by recording the ground reaction forces on a cylindrical object with either a smooth or anti-adhesive, rough surface. Furthermore, we measured the contact area of fore and hindlimbs against differently sized transparent cylinders and the forces of individual pads and subarticular tubercles in restrained animals. Our study revealed that frogs use friction and normal forces of roughly a similar magnitude for holding on to cylindrical objects. When challenged with climbing a non-adhesive surface, the compressive forces between opposite legs nearly doubled, indicating a stronger clamping grip. In contrast to climbing flat surfaces, frogs increased the contact area on all limbs by engaging not just adhesive pads but also subarticular tubercles on curved surfaces. Our force measurements showed that tubercles can withstand larger shear stresses than pads. SEM images of tubercles revealed a similar structure to that of toe pads including the presence of nanopillars, though channels surrounding epithelial cells were less pronounced. The tubercles' smaller size, proximal location on the toes and shallow cells make them probably less prone to buckling and thus ideal for gripping curved surfaces. PMID:28228509

The Improvement of Laparoscopic Surgical Skills Obtained by Gynecologists after Ten Years of Clinical Training Can Reduce Peritoneal Adhesion Formation during Laparoscopic Myomectomy: A Retrospective Cohort Study

PubMed Central

Peiretti, Michele; Minerba, Luigi

2017-01-01

Objective To evaluate if improvement of laparoscopic skills can reduce postoperative peritoneal adhesion formation in a clinical setting. Study Design We retrospectively evaluated 25 women who underwent laparoscopic myomectomy from January 1993 to June 1994 and 22 women who underwent laparoscopic myomectomy from March 2002 to November 2004. Women had one to four subserous/intramural myomas and received surgery without antiadhesive agents or barriers. Women underwent second-look laparoscopy for assessment of peritoneal adhesion formation 12 to 14 weeks after myomectomy. Adhesions were graded according to the Operative Laparoscopy Study Group scoring system. The main variable to be compared between the two cohorts was the proportion that showed no adhesions at second-look laparoscopy. Results Demographic and surgical characteristics were similar between the two cohorts. No complications were observed during surgery. No adverse events were recorded during postoperative course. At second-look laparoscopy, a higher proportion of adhesion-free patients was observed in women who underwent laparoscopic myomectomy from March 2002 to November 2004 (9 out of 22) compared with women who underwent the same surgery from January 1993 to June 1994 (3 out of 25). Conclusion The improvement of surgeons' skills obtained after ten years of surgery can reduce postoperative adhesion formation. PMID:29410967

Unique natural exopolysaccharides for biomimetic protective effect against urban pollution.

PubMed

Borel, Magali; Lamarque, Elisabeth; Loing, Estelle

Through natural selection, living organisms have evolved well-adapted survival strategies over time. The shallow salt waters of Moorea lagoon are the site of accumulation of microbial mats called "Kopara," in the native Polynesian language. This unique ecosystem is rich in film-forming exopolysaccharides (EPSs) secreted by microorganisms within the biofilm, as a mean to protect themselves from environmental stress (strong ultraviolet [UV], pH, salinity … ). Using blue biotechnology, a manufacturing process was developed to obtain an EPS with skin benefits. The active ingredient (EPS-229) protects against urban pollution, including free radicals, heavy metals, hydrocarbons, and PM 2.5 (particulate matter with a size lower than 2.5 μm). The anti-lipid peroxidation action of EPS-229 was studied in an in vitro UVB-irradiated keratinocyte culture model, using lipophilic fluorescent probe. The chelating properties of EPS-229 were evaluated in tubo in the presence of cadmium and lead. The protective effect of EPS-229 on pollution-exposed skin explants was investigated through quantification of released malondialdehyde (MDA) and histological observation of skin morphology using optical microscopy. Clinical evaluation of the protective and cleansing efficacy of a water solution containing EPS-229 (0.02% and 0.01% w/v, respectively) was performed, against placebo, on a panel of 18 volunteers. For these studies, the forearms of volunteers were treated with EPS-229 before (anti-adhesion affect) or after (cleansing effect) application of PM 2.5 (iron particles of 1 μm). The presence of skin-adherent particles was observed and quantified by image analysis, using specific digital masks. In vitro , EPS-229 significantly protected keratinocyte cell membranes from lipid peroxidation. A decrease of 28% was achieved when a concentration of 0.001% w/v EPS-229 was applied to the cell culture. In tubo , EPS-229 also presented strong chelating properties. Maximal adsorption was estimated at 154 mg/g (1.37 mmol/g) of EPS-299 for cadmium and at 250 mg/g (1.21 mmol/g) of EPS-229 for lead. In the skin explant model of pollution exposure, EPS-229 (0.03% w/v) reduced MDA production by 44%, preserved cell integrity, improved dermal-epidermal cohesion, and normalized the collagen network. In vivo , treatment of skin with EPS-229 before exposure to PM 2.5 created a protective film limiting particle adhesion. When used in a cleansing solution after exposure to PM 2.5 , EPS-229 formed a mesh that entrapped particles and removed them from the skin surface. Inspired by the French Polynesia Kopara unique ecosystem, a bioactive exopolysaccharide (EPS-229) has been developed that offers protection from environmental aggression. As a biomimetic shield at the surface of the skin, EPS-229 provides an immediate multiprotective action that efficiently fights the harmful effects of urban pollution and smog.

Vitamin E Phosphate Coating Stimulates Bone Deposition in Implant-related Infections in a Rat Model.

PubMed

Lovati, Arianna B; Bottagisio, Marta; Maraldi, Susanna; Violatto, Martina B; Bortolin, Monica; De Vecchi, Elena; Bigini, Paolo; Drago, Lorenzo; Romanò, Carlo L

2018-06-01

Implant-related infections are associated with impaired bone healing and osseointegration. In vitro antiadhesive and antibacterial properties and in vivo antiinflammatory effects protecting against bone loss of various formulations of vitamin E have been demonstrated in animal models. However, to the best of our knowledge, no in vivo studies have demonstrated the synergistic activity of vitamin E in preventing bacterial adhesion to orthopaedic implants, thus supporting the bone-implant integration. The purpose of this study was to test whether a vitamin E phosphate coating on titanium implants may be able to reduce (1) the bacterial colonization of prosthetic implants and (2) bone resorption and osteomyelitis in a rat model of Staphylococcus aureus-induced implant-related infection. Twelve rats were bilaterally injected in the femurs with S aureus UAMS-1-Xen40 and implanted with uncoated or vitamin E phosphate-coated titanium Kirschner wires without local or systemic antibiotic prophylaxis. Eight rats represented the uninfected control group. A few hours after surgery, two control and three infected animals died as a result of unexpected complications. With the remaining rats, we assessed the presence of bacterial contamination with qualitative bioluminescence imaging and Gram-positive staining and with quantitative bacterial count. Bone changes in terms of resorption and osteomyelitis were quantitatively analyzed through micro-CT (bone mineral density) and semiquantitatively through histologic scoring systems. Six weeks after implantation, we found only a mild decrease in bacterial count in coated versus uncoated implants (Ti versus controls: mean difference [MD], -3.705; 95% confidence interval [CI], -4.416 to -2.994; p < 0.001; TiVE versus controls: MD, -3.063; 95% CI, -3.672 to -2.454; p < 0.001), whereas micro-CT analysis showed a higher bone mineral density at the knee and femoral metaphysis in the vitamin E-treated group compared with uncoated implants (knee joint: MD, -11.88; 95% CI, -16.100 to -7.664; p < 0.001 and femoral metaphysis: MD, -19.87; 95% CI, -28.82 to -10.93; p < 0.001). We found decreased osteonecrosis (difference between medians, 1.5; 95% CI, 1-2; p < 0.002) in the infected group receiving the vitamin E-coated nails compared with the uncoated nails. These preliminary findings indicate that vitamin E phosphate implant coatings can exert a protective effect on bone deposition in a highly contaminated animal model of implant-related infection. The use of vitamin E coatings may open new perspectives for developing coatings that can limit septic loosening of infected implants with bacterial contamination. However, a deeper insight into the mechanism of action and the local release of vitamin E as a coating for orthopaedic implants is required to be used in clinics in the near future. Although this study cannot support the antimicrobial properties of vitamin E, promising results were obtained for bone-implant osseointegration. These preliminary results will require further in vivo investigations to optimize the host response in the presence of antibiotic prophylaxis.

Homing of human B cells to lymphoid organs and B-cell lymphoma engraftment are controlled by cell adhesion molecule JAM-C.

PubMed

Doñate, Carmen; Ody, Christiane; McKee, Thomas; Ruault-Jungblut, Sylvie; Fischer, Nicolas; Ropraz, Patricia; Imhof, Beat A; Matthes, Thomas

2013-01-15

Junctional adhesion molecule C (JAM-C) is expressed by vascular endothelium and human but not mouse B lymphocytes. The level of JAM-C expression defines B-cell differentiation stages and allows the classification of marginal zone-derived (JAM-C-positive) and germinal center-derived (JAM-C-negative) B-cell lymphomas. In the present study, we investigated the role of JAM-C in homing of human B cells, using a xenogeneic nonobese diabetic/severe combined immunodeficient mouse model. Treatment with anti-JAM-C antibodies in short-term experiments reduced migration of normal and malignant JAM-C-expressing B cells to bone marrow, lymph nodes, and spleen. Blocking homing to the spleen is remarkable, as most other antiadhesion antibodies reduce homing of B cells only to bone marrow and lymph nodes. Long-term administration of anti-JAM-C antibodies prevented engraftment of JAM-Cpos lymphoma cells in bone marrow, spleen, and lymph nodes of mice. Plasmon resonance studies identified JAM-B as the major ligand for JAM-C, whereas homotypic JAM-C interactions remained at background levels. Accordingly, anti-JAM-C antibodies blocked adhesion of JAM-C-expressing B cells to their ligand JAM-B, and immunofluorescence analysis showed the expression of JAM-B on murine and human lymphatic endothelial cells. Targeting JAM-C could thus constitute a new therapeutic strategy to prevent lymphoma cells from reaching supportive microenvironments not only in the bone marrow and lymph nodes but also in the spleen.

PVA gel as a potential adhesion barrier: a safety study in a large animal model of intestinal surgery.

PubMed

Renz, Bernhard W; Leitner, Kurt; Odermatt, Erich; Worthley, Daniel L; Angele, Martin K; Jauch, Karl-Walter; Lang, Reinhold A

2014-03-01

Intra-abdominal adhesions following surgery are a major source of morbidity and mortality including abdominal pain and small bowel obstruction. This study evaluated the safety of PVA gel (polyvinyl alcohol and carboxymethylated cellulose gel) on intestinal anastomoses and its potential effectiveness in preventing adhesions in a clinically relevant large animal model. Experiments were performed in a pig model with median laparotomy and intestinal anastomosis following small bowel resection. The primary endpoint was the safety of PVA on small intestinal anastomoses. We also measured the incidence of postoperative adhesions in PVA vs. control groups: group A (eight pigs): stapled anastomosis with PVA gel compared to group B (eight pigs), which had no PVA gel; group C (eight pigs): hand-sewn anastomosis with PVA gel compared to group B (eight pigs), which had no anti-adhesive barrier. Animals were sacrificed 14 days after surgery and analyzed. All anastomoses had a patent lumen without any stenosis. No anastomoses leaked at an intraluminal pressure of 40 cmH2O. Thus, anastomoses healed very well in both groups, regardless of whether PVA was administered. PVA-treated animals, however, had significantly fewer adhesions in the area of stapled anastomoses. The hand-sewn PVA group also had weaker adhesions and trended towards fewer adhesions to adjacent organs. These results suggest that PVA gel does not jeopardize the integrity of intestinal anastomoses. However, larger trials are needed to investigate the potential of PVA gel to prevent adhesions in gastrointestinal surgery.

Peptides Derived from a Phage Display Library Inhibit Adhesion and Protect the Host against Infection by Paracoccidioides brasiliensis and Paracoccidioides lutzii

PubMed Central

de Oliveira, Haroldo C.; Michaloski, Jussara S.; da Silva, Julhiany F.; Scorzoni, Liliana; de Paula e Silva, Ana C. A.; Marcos, Caroline M.; Assato, Patrícia A.; Yamazaki, Daniella S.; Fusco-Almeida, Ana M.; Giordano, Ricardo J.; Mendes-Giannini, Maria J. S.

2016-01-01

Paracoccidioides brasiliensis and Paracoccidioides lutzii are dimorphic fungi and are the etiological agents of paracoccidioidomycosis (PCM). Adhesion is one of the most important steps in infections with Paracoccidioides and is responsible for the differences in the virulence of isolates of these fungi. Because of the importance of adhesion to the establishment of an infection, this study focused on the preliminary development of a new therapeutic strategy to inhibit adhesion by Paracoccidioides, thus inhibiting infection and preventing the disease. We used two phage display libraries to select peptides that strongly bind to the Paracoccidioides cell wall to inhibit adhesion to host cells and extracellular matrix (ECM) components (laminin, fibronectin, and type I and type IV collagen). This approach allowed us to identify four peptides that inhibited up to 64% of the adhesion of Paracoccidioides to pneumocytes in vitro and inhibited the adhesion to the ECM components by up to 57%. Encouraged by these results, we evaluated the ability of these peptides to protect Galleria mellonella from Paracoccidioides infection by treating G. mellonella larvae with the different peptides prior to infection with Paracoccidioides and observing larval survival. The results show that all of the peptides tested increased the survival of the larvae infected with P. brasiliensis by up to 64% and by up to 60% in those infected with P. lutzii. These data may open new horizons for therapeutic strategies to prevent PCM, and anti-adhesion therapy could be an important strategy. PMID:28066254

Evaluation of tetraethoxysilane (TEOS) sol-gel coatings, modified with green synthesized zinc oxide nanoparticles for combating microfouling.

PubMed

Krupa, A Nithya Deva; Vimala, R

2016-04-01

Green synthesis of zinc oxide nanoparticles (ZnO-NPs) is gaining importance as an eco-friendly alternative to conventional methods due to its enormous applications. The present work reports the synthesis of ZnO-NPs using the endosperm of Cocos nucifera (coconut water) and the bio-molecules responsible for nanoparticle formation have been identified. The synthesized nanoparticles were characterized using UV-Visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM) and Zeta potential measurement. The results obtained reveal that the synthesized nanoparticles are moderately stable with the size ranging from 20 to 80 nm. The bactericidal effect of the nanoparticles was proved by well diffusion assay and determination of minimum inhibitory concentration (MIC) against marine biofilm forming bacteria. Further the green synthesized ZnO-NPs were doped with TEOS sol-gels (TESGs) in order to assess their antimicrofouling capability. Different volumes of liquid sol-gels were coated on to 96-well microtitre plate and cured under various conditions. The optimum curing conditions were found to be temperature 60 °C, time 72 h and volume 200 μl. Antiadhesion test of the undoped (SG) and ZnO-NP doped TEOS sol-gel (ZNSG) coatings were evaluated using marine biofilm forming bacteria. ZNSG coatings exhibited highest biofilm inhibition (89.2%) represented by lowest OD value against Pseudomonasotitidis strain NV1. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of polylactic film (Surgi-Wrap) on preventing postoperative ileus after major hepato-pancreato-biliary surgery

PubMed Central

Lee, Chang Hyung; Kim, Hongbeom; Kim, Suh Min; Kwak, Beom Seok; Baik, Yong Hae; Park, Young Jin; Oh, Min Gu

2016-01-01

Backgrounds/Aims Major hepato-pancreato-biliary (HPB) surgery is usually performed via an open method rather than a laparoscopic method. Postoperative ileus (POI) is a classic complication after open surgery. The purpose of this study was to determine whether polylactic film is useful in the prevention of POI. Methods A total of 179 patients who underwent major HPB surgery between 2005 and 2014, were retrospectively reviewed. A diagnosis of POI was made by a physical examination, laboratory, and radiological findings. Surgi-Wrap® polylactic film was preferentially used intraperitoneally by surgeons, just before wound closure. Results Major HPB surgery included pancreatoduodenectomy (n=48), distal or subtotal pancreatectomy (n=24), hepatectomy (n=67), other bile duct or gallbladder operations (n=35), and others (n=5). Although patients with polylactic film showed a significantly lower incidence of POI (n=3, 4.1% vs. n=14, 13.3%, p=0.041), they showed a significantly higher complication rate (n=20, 27.0% vs. n=19, 18.1%, p=0.004), particularly intra-abdominal fluid collection (n=7, 9.4% vs. n=2, 1.9%), and wound infections (n=6, 8.1% vs. n=3, 2.9%), than those who did not receive the film, respectively. Conclusions Although the polylactic film prevented POI, more complications other than POI were observed. Well-designed randomized controlled trials, using this anti-adhesive product, are needed to evaluate its effect on POI after major HPB surgery. PMID:28261699

Efficacy of Seprafilm for preventing adhesive bowel obstruction and cost-benefit analysis in pediatric patients undergoing laparotomy.

PubMed

Inoue, Mikihiro; Uchida, Keiichi; Otake, Kohei; Nagano, Yuka; Ide, Shozo; Hashimoto, Kiyoshi; Matsushita, Kohei; Koike, Yuhki; Mohri, Yasuhiko; Kusunoki, Masato

2013-07-01

This aim of the study is to determine whether the use of Seprafilm reduces the incidence and the medical costs of adhesive bowel obstruction (ABO) in children. Pediatric patients undergoing laparotomy were prospectively assigned to the Seprafilm group, n = 441). A historical control group consisted of children without using Seprafilm (n = 409). The incidence of ABO during a 24-month follow-up period was compared between the groups. To clarify the cost-benefit relations, expenses for Seprafilm and medical costs for hospitalization related to ABO in the Seprafilm group were compared with the ABO-associated hospitalization costs in the control group. The cumulative incidence rate of ABO in the control group was significantly higher than in the Seprafilm group (4.9% vs. 2.0%, p = 0.015). Nearly all cases that required adhesiolysis had adhesions to areas other than the incision in both groups. In cost-benefit analysis, cost per patient was $105 higher in the control group than in the Seprafilm group, but this did not reach significance (p = 0.63). Seprafilm reduces the incidence of ABO in the pediatric patients undergoing laparotomy. Although associated medical costs in the Seprafilm group were not significantly reduced, use of Seprafilm did not lead to an increase in cost. Wider range of Seprafilm application or an additional anti-adhesion device may help in preventing adhesion to areas other than the incision. Copyright © 2013 Elsevier Inc. All rights reserved.

Designing a VAR2CSA-based vaccine to prevent placental malaria.

PubMed

Fried, Michal; Duffy, Patrick E

2015-12-22

Placental malaria (PM) due to Plasmodium falciparum is a major cause of maternal, fetal and infant mortality, but the mechanisms of pathogenesis and protective immunity are relatively well-understood for this condition, providing a path for vaccine development. P. falciparum parasites bind to chondroitin sulfate A (CSA) to sequester in the placenta, and women become resistant over 1-2 pregnancies as they acquire antibodies that block adhesion to CSA. The protein VAR2CSA, a member of the PfEMP1 variant surface antigen family, mediates parasite adhesion to CSA, and is the leading target for a vaccine to prevent PM. Obstacles to PM vaccine development include the large size (∼ 350 kD), high cysteine content, and sequence variation of VAR2CSA. A number of approaches have been taken to identify the combination of VAR2CSA domains and alleles that can induce broadly active antibodies that block adhesion of heterologous parasite isolates to CSA. This review summarizes these approaches, which have examined VAR2CSA fragments for binding activity, antigenicity with naturally acquired antibodies, and immunogenicity in animals for inducing anti-adhesion or surface-reactive antibodies. Two products are expected to enter human clinical studies in the near future based on N-terminal VAR2CSA fragments that have high binding affinity for CSA, and additional proteins preferentially expressed by placental parasites are also being examined for their potential contribution to a PM vaccine. Copyright © 2015. Published by Elsevier Ltd.

Anti-adhesion activity of thyme (Thymus vulgaris L.) extract, thyme post-distillation waste, and olive (Olea europea L.) leaf extract against Campylobacter jejuni on polystyrene and intestine epithelial cells.

PubMed

Šikić Pogačar, Maja; Klančnik, Anja; Bucar, Franz; Langerholc, Tomaž; Smole Možina, Sonja

2016-06-01

In order to survive in food-processing environments and cause disease, Campylobacter jejuni requires specific survival mechanisms, such as biofilms, which contribute to its transmission through the food chain to the human host and present a critical form of resistance to a wide variety of antimicrobials. Phytochemical analysis of thyme ethanolic extract (TE), thyme post-hydrodistillation residue (TE-R), and olive leaf extract (OE) using high-performance liquid chromatography with photodiode array indicates that the major compounds in TE and TE-R are flavone glucuronides and rosmarinic acid derivatives, and in OE verbascoside, luteolin 7-O-glucoside and oleuroside. TE and TE-R reduced C. jejuni adhesion to abiotic surfaces by up to 30% at 0.2-12.5 µg mL(-1) , with TE-R showing a greater effect. OE from 3.125 to 200 µg mL(-1) reduced C. jejuni adhesion to polystyrene by 10-23%. On the other hand, C. jejuni adhesion to PSI cl1 cells was inhibited by almost 30% over a large concentration range of these extracts. Our findings suggest that TE, the agro-food waste material TE-R, and the by-product OE represent sources of bioactive phytochemicals that are effective at low concentrations and can be used as therapeutic agents to prevent bacterial adhesion. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Surface wettability of plasma SiOx:H nanocoating-induced endothelial cells' migration and the associated FAK-Rho GTPases signalling pathways

PubMed Central

Shen, Yang; Wang, Guixue; Huang, Xianliang; Zhang, Qin; Wu, Jiang; Tang, Chaojun; Yu, Qingsong; Liu, Xiaoheng

2012-01-01

Vascular endothelial cell (EC) adhesion and migration are essential processes in re-endothelialization of implanted biomaterials. There is no clear relationship and mechanism between EC adhesion and migration behaviour on surfaces with varying wettabilities. As model substrates, plasma SiOx:H nanocoatings with well-controlled surface wettability (with water contact angles in the range of 98.5 ± 2.3° to 26.3 ± 4.0°) were used in this study to investigate the effects of surface wettability on cell adhesion/migration and associated protein expressions in FAK-Rho GTPases signalling pathways. It was found that EC adhesion/migration showed opposite behaviour on the hydrophilic and hydrophobic surfaces (i.e. hydrophobic surfaces promoted EC migration but were anti-adhesions). The number of adherent ECs showed a maximum on hydrophilic surfaces, while cells adhered to hydrophobic surfaces exhibited a tendency for cell migration. The focal adhesion kinase (FAK) inhibitor targeting the Y-397 site of FAK could significantly inhibit cell adhesion/migration, suggesting that EC adhesion and migration on surfaces with different wettabilities involve (p)FAK and its downstream signalling pathways. Western blot results suggested that the FAK-Rho GTPases signalling pathways were correlative to EC migration on hydrophobic plasma SiOx:H surfaces, but uncertain to hydrophilic surfaces. This work demonstrated that surface wettability could induce cellular behaviours that were associated with different cellular signalling events. PMID:21715399

Stable Binding of Alternative Protein-enriched Food Matrices with Concentrated Cranberry Bioflavonoids for Functional Food Applications

PubMed Central

Grace, Mary H.; Guzman, Ivette; Roopchand, Diana E.; Moskal, Kristin; Cheng, Diana M.; Pogrebnyak, Natasha; Raskin, Ilya; Howell, Amy; Lila, Mary Ann

2013-01-01

Defatted soy flour (DSF), soy protein isolate (SPI), hemp protein isolate (HPI), medium roast peanut flour (MPF) and pea protein isolate (PPI) stably bind and concentrate cranberry (CB) polyphenols, creating protein/polyphenol-enriched matrices. Proanthocyanidins (PAC) in the enriched matrices ranged from 20.75 mg/g (CB-HPI) to 10.68 mg/g (CB-SPI). Anthocyanins (ANC) ranged from 3.19 mg/g (CB-DSF) to 1.68 mg/g (CB-SPI), while total phenolics (TP) ranged from 37.61 mg/g (CB-HPI) to 21.29 mg/g (CB-SPI). LC-MS indicated that the enriched matrices contained all identifiable ANC, PAC and flavonols present in CB juice. Complexation with SPI stabilized and preserved the integrity of the CB polyphenolic components for at least 15 weeks at 37 °C. PAC isolated from enriched matrices demonstrated comparable anti-adhesion bioactivity to PAC isolated directly from CB juice (MIC 0.4 to 0.16 mg/mL), indicating their potential utility for maintenance of urinary tract health. Approximately 1.0 g of polyphenol-enriched matrix delivered the same amount of PAC available in one cup (300 mL) of commercial CB juice cocktail; which has been shown clinically to be the prophylactic dose for reducing recurring urinary tract infections. CB-SPI inhibited gram- positive and gram-negative bacterial growth. Nutritional and sensory analyses indicated that the targeted CB-matrix combinations have high potential for incorporation in functional food formulations. PMID:23786629

Consumption of cranberry beverage improved endogenous antioxidant status and protected against bacteria adhesion in healthy humans: a randomized controlled trial.

PubMed

Mathison, Bridget D; Kimble, Lindsey L; Kaspar, Kerrie L; Khoo, Christina; Chew, Boon P

2014-05-01

Consumption of polyphenol-rich foods is associated with lower risk from many chronic diseases. We hypothesized that a single dose of cranberry beverage would improve indices of oxidative stress, inflammation, and urinary antibacterial adhesion activity in healthy humans. Six males and 6 females (18-35 years; body mass index, 19-25 kg/m(2)) consumed placebo, cranberry leaf extract beverage, or low-calorie cranberry juice cocktail (LCJC) once in a randomized, double-blind, placebo-controlled cross-over experimental design trial. The washout period between beverages was 1 week. Blood was collected 0, 2, 4, 8, and 24 hours after beverage consumption for measuring oxidative and inflammatory biomarkers. Urine was collected at 0, 0 to 3, 3 to 6, 6 to 9, 9 to 12, and 24 hours postintervention to assess antibacterial adhesion activity. Consumption of cranberry leaf extract beverage elevated (P < .05) blood glutathione peroxidase activity, whereas LCJC consumption increased (P < .05) glutathione concentrations and superoxide dismutase activity compared with placebo. Cranberry leaf extract beverage and LCJC consumption had no effect on the inflammatory biomarkers measured as compared with placebo. At 0 to 3 hours postconsumption, urine from participants who consumed cranberry beverages had higher (P < .05) ex vivo antiadhesion activity against P-fimbriated Escherichia coli compared with placebo. An acute dose of cranberry beverages improved biomarkers of antioxidant status and inhibition of bacterial adhesion in urine. Copyright © 2014 Elsevier Inc. All rights reserved.

Neuropeptides, via specific receptors, regulate T cell adhesion to fibronectin.

PubMed

Levite, M; Cahalon, L; Hershkoviz, R; Steinman, L; Lider, O

1998-01-15

The ability of T cells to adhere to and interact with components of the blood vessel walls and the extracellular matrix is essential for their extravasation and migration into inflamed sites. We have found that the beta1 integrin-mediated adhesion of resting human T cells to fibronectin, a major glycoprotein component of the extracellular matrix, is induced by physiologic concentrations of three neuropeptides: calcitonin gene-related protein (CGRP), neuropeptide Y, and somatostatin; each acts via its own specific receptor on the T cell membrane. In contrast, substance P (SP), which coexists with CGRP in the majority of peripheral endings of sensory nerves, including those innervating the lymphoid organs, blocks T cell adhesion to fibronectin when induced by CGRP, neuropeptide Y, somatostatin, macrophage inflammatory protein-1beta, and PMA. Inhibition of T cell adhesion was obtained both by the intact SP peptide and by its 1-4 N-terminal and its 4-11, 5-11, and 6-11 C-terminal fragments, used at similar nanomolar concentrations. The inhibitory effects of the parent SP peptide and its fragments were abrogated by an SP NK-1 receptor antagonist, suggesting they all act through the same SP NK-1 receptor. These findings suggest that neuropeptides, by activating their specific T cell-expressed receptors, can provide the T cells with both positive (proadhesive) and negative (antiadhesive) signals and thereby regulate their function. Thus, neuropeptides may influence diverse physiologic processes involving integrins, including leukocyte-mediated migration and inflammation.

Human milk oligosaccharides: every baby needs a sugar mama.

PubMed

Bode, Lars

2012-09-01

Human milk oligosaccharides (HMOs) are a family of structurally diverse unconjugated glycans that are highly abundant in and unique to human milk. Originally, HMOs were discovered as a prebiotic "bifidus factor" that serves as a metabolic substrate for desired bacteria and shapes an intestinal microbiota composition with health benefits for the breast-fed neonate. Today, HMOs are known to be more than just "food for bugs". An accumulating body of evidence suggests that HMOs are antiadhesive antimicrobials that serve as soluble decoy receptors, prevent pathogen attachment to infant mucosal surfaces and lower the risk for viral, bacterial and protozoan parasite infections. In addition, HMOs may modulate epithelial and immune cell responses, reduce excessive mucosal leukocyte infiltration and activation, lower the risk for necrotizing enterocolitis and provide the infant with sialic acid as a potentially essential nutrient for brain development and cognition. Most data, however, stem from in vitro, ex vivo or animal studies and occasionally from association studies in mother-infant cohorts. Powered, randomized and controlled intervention studies will be needed to confirm relevance for human neonates. The first part of this review introduces the pioneers in HMO research, outlines HMO structural diversity and describes what is known about HMO biosynthesis in the mother's mammary gland and their metabolism in the breast-fed infant. The second part highlights the postulated beneficial effects of HMO for the breast-fed neonate, compares HMOs with oligosaccharides in the milk of other mammals and in infant formula and summarizes the current roadblocks and future opportunities for HMO research.

Comparison of the effects of Mitomycin-C and sodium hyaluronate/carboxymethylcellulose [NH/CMC] (Seprafilm) on abdominal adhesions.

PubMed

Ozerhan, Ismail Hakkı; Urkan, Murat; Meral, Ulvi Mehmet; Unlu, Aytekin; Ersöz, Nail; Demirag, Funda; Yagci, Gokhan

2016-01-01

Intra-abdominal adhesions (IA) may occur after abdominal surgery and also may lead to complications such as infertility, intestinal obstruction and chronic pain. The aim of this study was to compare the effects of Mitomycin-C (MM-C) and sodium hyaluronate/carboxymethylcellulose [NH/CMC] on abdominal adhesions in a cecal abrasion model and to investigate the toxicity of MM-C on complete blood count (CBC) and bone marrow analyses. The study comprised forty rats in four groups (Control, Sham, Cecal abrasion + MM-C, and Cecal abrasion + NH/CMC). On postoperative day 21, all rats except for the control (CBC + femur resection) group, were sacrificed. Macroscopical and histopathological evaluations of abdominal adhesions were performed. In order to elucidate the side effects of MM-C; CBC analyses and femur resections were performed to examine bone marrow cellularity. CBC analyses and bone marrow cellularity assessment revealed no statistically significant differences between MM-C, NH/CMC and control groups. No significant differences in inflammation scores were observed between the groups. The MM-C group had significantly lower fibrosis scores compared to the NH/CMC and sham groups. Although the adhesion scores were lower in the MM-C group, the differences were not statistically significant. Despite its potential for systemic toxicity, MM-C may show some anti-fibrosis and anti-adhesive effects. MM-C is a promising agent for the prevention of IAs, and as such, further trials are warranted to study efficacy.

Metastatic outgrowth encompasses COL-I, FN1, and POSTN up-regulation and assembly to fibrillar networks regulating cell adhesion, migration, and growth.

PubMed

Soikkeli, Johanna; Podlasz, Piotr; Yin, Miao; Nummela, Pirjo; Jahkola, Tiina; Virolainen, Susanna; Krogerus, Leena; Heikkilä, Päivi; von Smitten, Karl; Saksela, Olli; Hölttä, Erkki

2010-07-01

Although the outgrowth of micrometastases into macrometastases is the rate-limiting step in metastatic progression and the main determinant of cancer fatality, the molecular mechanisms involved have been little studied. Here, we compared the gene expression profiles of melanoma lymph node micro- and macrometastases and unexpectedly found no common up-regulation of any single growth factor/cytokine, except for the cytokine-like SPP1. Importantly, metastatic outgrowth was found to be consistently associated with activation of the transforming growth factor-beta signaling pathway (confirmed by phospho-SMAD2 staining) and concerted up-regulation of POSTN, FN1, COL-I, and VCAN genes-all inducible by transforming growth factor-beta. The encoded extracellular matrix proteins were found to together form intricate fibrillar networks around tumor cell nests in melanoma and breast cancer metastases from various organs. Functional analyses suggested that these newly synthesized protein networks regulate adhesion, migration, and growth of tumor cells, fibroblasts, and endothelial cells. POSTN acted as an anti-adhesive molecule counteracting the adhesive functions of FN1 and COL-I. Further, cellular FN and POSTN were specifically overexpressed in the newly forming/formed tumor blood vessels. Transforming growth factor-beta receptors and the metastasis-related matrix proteins, POSTN and FN1, in particular, may thus provide attractive targets for development of new therapies against disseminated melanoma, breast cancer, and possibly other tumors, by affecting key processes of metastasis: tumor/stromal cell migration, growth, and angiogenesis.

Prevention of Pleural Adhesions by Bioactive Polypeptides - A Pilot Study

PubMed Central

Åkerberg, D.; Posaric-Bauden, M.; Isaksson, K.; Andersson, R.; Tingstedt, B.

2013-01-01

Objective: Postoperative pleural adhesions lead to major problems in repeated thoracic surgery. To date, no antiadhesive product has been proven clinically effective. Previous studies of differently charged polypeptides, poly-L-lysine (PL) and poly-L-glutamate (PG) have shown promising results reducing postoperative abdominal adhesions in experimental settings. This pilot study examined the possible pleural adhesion prevention by using the PL+PG concept after pleural surgery and its possible effect on key parameters; plasmin activator inhibitor-1 (PAI-1) and tissue growth factor beta 1 (TGFb) in the fibrinolytic process. Methods: A total of 22 male rats were used in the study, one control group (n=10) and one experimental group (n=12). All animals underwent primary pleural surgery, the controls receiving saline in the pleural cavity and the experimental group the PL+PG solution administered by spray. The animals were evaluated on day 7. Macroscopic appearance of adhesions was evaluated by a scoring system. Histology slides of the adhesions and pleural biopsies for evaluation of PAI-1 and TGFb1 were taken on day 7. Results: A significant reduction of adhesions in the PL+PG group (p<0.05) was noted at day 7 both regarding the length and severity of adhesions. There were no significant differences in the concentration of PAI-1 and TGFb1 when comparing the two groups. Conclusions: PL+PG may be used to prevent pleural adhesions. The process of fibrinolysis, and fibrosis was though not affected after PLPG administration. PMID:24151443

[Strategies and surgical management of endometriosis: CNGOF-HAS Endometriosis Guidelines].

PubMed

Roman, H; Ballester, M; Loriau, J; Canis, M; Bolze, P A; Niro, J; Ploteau, S; Rubod, C; Yazbeck, C; Collinet, P; Rabischong, B; Merlot, B; Fritel, X

2018-03-01

The article presents French guidelines for surgical management of endometriosis. Surgical treatment is recommended for mild to moderate endometriosis, as it decreases pelvic painful complaints and increases the likelihood of postoperative conception in infertile patients (A). Surgery may be proposed in symptomatic patients with ovarian endometriomas which diameter exceeds 20mm. Cystectomy allows for better postoperative pregnancy rates when compared to ablation using bipolar current, as well as for lower recurrences rates when compared to ablation using bipolar current or CO 2 laser. Ablation of ovarian endometriomas using bipolar current is not recommended (B). Surgery may be employed in patients with deep endometriosis infiltrating the colon and the rectum, with good impact on painful complaints and postoperative conception. In these patients, laparoscopic route increases the likelihood of postoperative spontaneous conception when compared to open route. When compared to conservative rectal procedures (shaving or disc excision), segmental colorectal resection increases the risk of postoperative stenosis, requiring additional endoscopic or surgical procedures. In large deep endometriosis infiltrating the rectum (>20mm length of bowel infiltration), conservative rectal procedures do not improve postoperative digestive function when compared to segmental resection. In patients with bowel anastomosis, placing anti-adhesion agents on contact with bowel suture is not recommended, due to higher risk of bowel fistula (C). Various other recommendations are proposed in the text, however, they are based on studies with low level of evidence. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Live Streptococcus suis type 5 strain XS045 provides cross-protection against infection by strains of types 2 and 9.

PubMed

Jiang, Xiaowu; Yang, Yunkai; Zhu, Lexin; Gu, Yuanxing; Shen, Hongxia; Shan, Ying; Li, Xiaoliang; Wu, Jiusheng; Fang, Weihuan

2016-12-12

Streptococcus suis is one of the common pathogens causing diseases in pigs and covers 35 serotypes with the type 2 strains being more pathogenic and zoonotic. Existing inactivated or subunit vaccines, in clinical use or under trial, could not provide cross protection against other serotypes. We identified a natural low-virulence S. suis type 5 strain XS045 as a live vaccine candidate because it is highly adhesive to the cultured HEp-2 cells, but with no apparent pathogenicity in mice and piglets. We further demonstrate that subcutaneous administration of the live XS045 strain to mice induced high antibody responses and was able to provide cross protection against challenges by a type 2 strain HA9801 (100% protection) and a type 9 strain JX13 (85% protection). Induction of high-titer antibodies with opsonizing activity as well as their cross-reactivity to surface proteins of the types 2 and 9 strains and anti-adhesion effect could be the mechanisms of cross protection. This is the first report that a live vaccine candidate S. suis type 5 strain could induce cross-protection against strains of types 2 and 9. This candidate strain is to be further examined for safety in pigs of different ages and breeds as well as for its protection against other serotypes or other strains of the type 2, a serotype of particular importance from public health concern. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biosurfactant from a marine bacterium disrupts biofilms of pathogenic bacteria in a tropical aquaculture system.

PubMed

Hamza, Faseela; Satpute, Surekha; Banpurkar, Arun; Kumar, Ameeta Ravi; Zinjarde, Smita

2017-11-01

Bacterial infections are major constraints in aquaculture farming. These pathogens often adapt to the biofilm mode of growth and resist antibiotic treatments. We have used a non-toxic glycolipid biosurfactant (BS-SLSZ2) derived from a marine epizootic bacterium Staphylococcus lentus to treat aquaculture associated infections in an eco-friendly manner. We found that BS-SLSZ2 contained threose, a four-carbon sugar as the glycone component, and hexadecanoic and octadecanoic acids as the aglycone components. The critical micelle concentration of the purified glycolipid was 18 mg mL-1. This biosurfactant displayed anti-adhesive activity and inhibited biofilm formation by preventing initial attachment of cells onto surfaces. The biosurfactant (at a concentration of 20 μg) was able to inhibit Vibrio harveyi and Pseudomonas aeruginosa biofilms by 80.33 ± 2.16 and 82 ± 2.03%, respectively. At this concentration, it was also able to disrupt mature biofilms of V. harveyi (78.7 ± 1.93%) and P. aeruginosa (81.7 ± 0.59%). The biosurfactant was non-toxic towards Artemia salina. In vivo challenge experiments showed that the glycolipid was effective in protecting A. salina nauplii against V. harveyi and P. aeruginosa infections. This study highlights the significance of marine natural products in providing alternative biofilm controlling agents and decreasing the usage of antibiotics in aquaculture settings. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

ANTI-ADHESIVE AND ANTI-BIOFILM ACTIVITIES IN VITRO OF LINEZOLID, VANCOMYCIN, TIGECYCLINE AND DAPTOMYCIN AGAINST STAPHYLOCOCCUS HAEMOLYTICUS.

PubMed

Juda, Marek; Helon, Pawel; Malm, Anna

2016-11-01

Biofilm may be formed on wide variety of surfaces, including indwelling medical devices, leading to several infectious diseases, e.g., bacteremia and sepsis. The most,important pathogens related with infections associated with medical devices are coagulase-negative staphylococci, including Staphylococcus haeinolyticus - bacterial species which express quite often the multidrug resistance. The four clinical multiresistant and methicillin-resistant S. haenzolyticus were included in the present study. The evaluation of drug susceptibility was performed by using disc-diffusion method and broth microdilution method according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. The biofilm formation on the Nelaton catheter and the effect of linezolid, vancomycin, tigecycline and daptomycin on the biofilm formation and disruption of mature structure was based on the method with TTC (2,3,5-triphenyltetrazolium chloride). The adhesion process of S. haenzolyticus to the Nelaton catheter was inhibited by antibiotics, as follows: line-zolid at concentration 0.25-0.5 x MIC, vancomycin - concentration 0.5 x MIC, tigecycline - concentration 0.25-4 x MIC and daptomycin - concentration 0.06-1 x MIC, depending on the isolate. Linezolid inhibited the biofilm formation at concentration between 0.5-1 x MIC, vancomycin - 1-2 x MIC, tigecycline - 0.5-4 x MIC and daptomycin - 0.06-2 x MIC. The concentration of linezolid eradicating the mature biofilm was found to be 1-2 x MIC, vancomycin - 2-8 x MIC, tigecycline - 2-4 x MIC and daptomycin - 0.06-2 x MIC. The most active antibiotic against S. haentolyticus biofilm formation and disruption of mature structure seems to be daptomycin.

Natural Antimicrobials and Oral Microorganisms: A Systematic Review on Herbal Interventions for the Eradication of Multispecies Oral Biofilms

PubMed Central

Karygianni, Lamprini; Al-Ahmad, Ali; Argyropoulou, Aikaterini; Hellwig, Elmar; Anderson, Annette C.; Skaltsounis, Alexios L.

2016-01-01

Oral diseases such as caries and periodontitis are mainly caused by microbial biofilms. Antibiotic therapy has reached its limits with regard to antimicrobial resistance, and new therapeutic measures utilizing natural phytochemicals are currently a focus of research. Hence, this systematic review provides a critical presentation of the antimicrobial effects of various medicinal herbs against in vitro, ex vivo, and in situ formed multispecies oral biofilms. Searches were performed in three English databases (PubMed, EMBASE, CAMbase) and the electronic archives of five German journals from the times of their establishment until October 10th, 2014, with the search terms “(plant extracts OR herbal extracts OR plant OR herb) AND (oral biofilm OR dental biofilm OR dental plaque OR oral disease OR dental disease).” The pooled data were assessed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA). Initially, 1848 articles were identified, out of which 585 full-text articles were screened, 149 articles were reevaluated for eligibility and finally, 14 articles met all inclusion criteria. The data of 14 reports disclosed enhanced antiadhesive and antibiofilm activity by the plant extracts obtained from Vitis vinifera, Pinus spp., Coffea canephora, Camellia sinensis, Vaccinium macrocarpon, Galla chinensis, Caesalpinia ferrea Martius, Psidium cattleianum, representative Brazilian plants and manuka honey. Overall, a positive correlation was revealed between herb-based therapies and elimination rates of all types of multispecies oral biofilms. In that context, integrating or even replacing conventional dental therapy protocols with herbal-inspired treatments can allow effective antimicrobial control of oral biofilms and thus, dental diseases. PMID:26834707

Aptamer-based hydrogel barcodes for the capture and detection of multiple types of pathogenic bacteria.

PubMed

Xu, Yueshuang; Wang, Huan; Luan, Chengxin; Liu, Yuxiao; Chen, Baoan; Zhao, Yuanjin

2018-02-15

Rapid and sensitive diagnosing hematological infections based on the separation and detection of pathogenic bacteria in the patient's blood is a significant challenge. To address this, we herein present a new barcodes technology that can simultaneously capture and detect multiple types of pathogenic bacteria from a complex sample. The barcodes are poly (ethylene glycol) (PEG) hydrogel inverse opal particles with characteristic reflection peak codes that remain stable during bacteria capture on their surfaces. As the spherical surface of the particles has ordered porous nanostructure, the barcodes can provide not only more surface area for probe immobilization and reaction, but also a nanopatterned platform for highly efficient bioreactions. In addition, the PEG hydrogel scaffold could decrease the non-specificity adsorption by its anti-adhesive effect, and the decorated aptamer probes in the scaffolds could increase the sensitivity, reliability, and specificity of the bacteria capture and detection. Moreover, the tagged magnetic nanoparticles in the PEG scaffold could impart the barcodes with controllable movement under magnetic fields, which can be used to significantly increase the reaction speed and simplify the processing of the bioassays. Based on the describe barcodes, it was demonstrated that the bacteria could be captured and identified even at low bacterial concentrations (100 CFU mL -1 ) within 2.5h, which is effectively shortened in comparison with the "gold standard" in clinic. These features make the barcodes ideal for capturing and detecting multiple bacteria from clinical samples for hematological infection diagnostics. Copyright © 2017 Elsevier B.V. All rights reserved.

Deposition of Fibrinogen on the Surface of in vitro Thrombi Prevents Platelet Adhesion

PubMed Central

Owaynat, Hadil; Yermolenko, Ivan S.; Turaga, Ramya; Lishko, Valeryi K.; Sheller, Michael R.; Ugarova, Tatiana P.

2015-01-01

The initial accumulation of platelets after vessel injury is followed by thrombin-mediated generation of fibrin which is deposited around the plug. While numerous in vitro studies have shown that fibrin is highly adhesive for platelets, the surface of experimental thrombi in vivo contains very few platelets suggesting the existence of natural anti-adhesive mechanisms protecting stabilized thrombi from platelet accumulation and continuous thrombus propagation. We previously showed that adsorption of fibrinogen on pure fibrin clots results in the formation of a nonadhesive matrix, highlighting a possible role of this process in surface-mediated control of thrombus growth. However, the deposition of fibrinogen on the surface of blood clots has not been examined. In this study, we investigated the presence of intact fibrinogen on the surface of fibrin-rich thrombi generated from flowing blood and determined whether deposited fibrinogen is nonadhesive for platelets. Stabilized fibrin-rich thrombi were generated using a flow chamber and the time that platelets spend on the surface of thrombi was determined by video recording. The presence of fibrinogen and fibrin on the surface of thrombi was analyzed by confocal microscopy using specific antibodies. Examination of the spatial distribution of two proteins revealed the presence of intact fibrinogen on the surface of stabilized thrombi. By manipulating the surface of thrombi to display either fibrin or intact fibrinogen, we found that platelets adhere to fibrin- but not to fibrinogen-coated thrombi. These results indicate that the fibrinogen matrix assembled on the outer layer of stabilized in vitro thrombi protects them from platelet adhesion. PMID:26482763

Deposition of fibrinogen on the surface of in vitro thrombi prevents platelet adhesion.

PubMed

Owaynat, Hadil; Yermolenko, Ivan S; Turaga, Ramya; Lishko, Valeryi K; Sheller, Michael R; Ugarova, Tatiana P

2015-12-01

The initial accumulation of platelets after vessel injury is followed by thrombin-mediated generation of fibrin which is deposited around the plug. While numerous in vitro studies have shown that fibrin is highly adhesive for platelets, the surface of experimental thrombi in vivo contains very few platelets suggesting the existence of natural anti-adhesive mechanisms protecting stabilized thrombi from platelet accumulation and continuous thrombus propagation. We previously showed that adsorption of fibrinogen on pure fibrin clots results in the formation of a nonadhesive matrix, highlighting a possible role of this process in surface-mediated control of thrombus growth. However, the deposition of fibrinogen on the surface of blood clots has not been examined. In this study, we investigated the presence of intact fibrinogen on the surface of fibrin-rich thrombi generated from flowing blood and determined whether deposited fibrinogen is nonadhesive for platelets. Stabilized fibrin-rich thrombi were generated using a flow chamber and the time that platelets spend on the surface of thrombi was determined by video recording. The presence of fibrinogen and fibrin on the surface of thrombi was analyzed by confocal microscopy using specific antibodies. Examination of the spatial distribution of two proteins revealed the presence of intact fibrinogen on the surface of stabilized thrombi. By manipulating the surface of thrombi to display either fibrin or intact fibrinogen, we found that platelets adhere to fibrin- but not to fibrinogen-coated thrombi. These results indicate that the fibrinogen matrix assembled on the outer layer of stabilized in vitro thrombi protects them from platelet adhesion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Production of hybrid macro/micro/nano surface structures on Ti6Al4V surfaces by picosecond laser surface texturing and their antifouling characteristics.

PubMed

Rajab, Fatema H; Liauw, Christopher M; Benson, Paul S; Li, Lin; Whitehead, Kathryn A

2017-12-01

The development of surfaces which reduce biofouling has attracted much interest in practical applications. Three picosecond laser generated surface topographies (Ti1, Ti2, Ti3) on titanium were produced, treated with fluoroalkylsilane (FAS), then characterised using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Raman Spectroscopy, Fourier Transform Infra-Red (FTIR) spectroscopy, contact angle measurements and white light interference microscopy. The surfaces had a range of different macro/micro/nano topographies. Ti2 had a unique, surface topography with large blunt conical peaks and was predominantly a rutile surface with closely packed, self-assembled FAS; this was the most hydrophobic sample (water contact angle 160°; ΔG iwi was -135.29mJm -2 ). Bacterial attachment, adhesion and retention to the surfaces demonstrated that all the laser generated surfaces retained less bacteria than the control surface. This also occurred following the adhesion and retention assays when the bacteria were either not rinsed from the surfaces or were retained in static conditions for one hour. This work demonstrated that picosecond laser generated surfaces may be used to produce antiadhesive surfaces that significantly reduced surface fouling. It was determined that a tri-modally dimensioned surface roughness, with a blunt conical macro-topography, combined with a close-packed fluoroalkyl monolayer was required for an optimised superhydrophobic surface. These surfaces were effective even following surface immersion and static conditions for one hour, and thus may have applications in a number of food or medical industries. Copyright © 2017 Elsevier B.V. All rights reserved.

Human milk oligosaccharides: Every baby needs a sugar mama

PubMed Central

Bode, Lars

2012-01-01

Human milk oligosaccharides (HMOs) are a family of structurally diverse unconjugated glycans that are highly abundant in and unique to human milk. Originally, HMOs were discovered as a prebiotic “bifidus factor” that serves as a metabolic substrate for desired bacteria and shapes an intestinal microbiota composition with health benefits for the breast-fed neonate. Today, HMOs are known to be more than just “food for bugs”. An accumulating body of evidence suggests that HMOs are antiadhesive antimicrobials that serve as soluble decoy receptors, prevent pathogen attachment to infant mucosal surfaces and lower the risk for viral, bacterial and protozoan parasite infections. In addition, HMOs may modulate epithelial and immune cell responses, reduce excessive mucosal leukocyte infiltration and activation, lower the risk for necrotizing enterocolitis and provide the infant with sialic acid as a potentially essential nutrient for brain development and cognition. Most data, however, stem from in vitro, ex vivo or animal studies and occasionally from association studies in mother–infant cohorts. Powered, randomized and controlled intervention studies will be needed to confirm relevance for human neonates. The first part of this review introduces the pioneers in HMO research, outlines HMO structural diversity and describes what is known about HMO biosynthesis in the mother's mammary gland and their metabolism in the breast-fed infant. The second part highlights the postulated beneficial effects of HMO for the breast-fed neonate, compares HMOs with oligosaccharides in the milk of other mammals and in infant formula and summarizes the current roadblocks and future opportunities for HMO research. PMID:22513036

Antimicrobial peptide AMPNT-6 from Bacillus subtilis inhibits biofilm formation by Shewanella putrefaciens and disrupts its preformed biofilms on both abiotic and shrimp shell surfaces.

PubMed

Deng, Qi; Pu, Yuehua; Sun, Lijun; Wang, Yaling; Liu, Yang; Wang, Rundong; Liao, Jianmeng; Xu, Defeng; Liu, Ying; Ye, Riying; Fang, Zhijia; Gooneratne, Ravi

2017-12-01

Shewanella putrefaciens biofilm formation is of great concern for the shrimp industry because it adheres easily to food and food-contact surfaces and is a source of persistent and unseen contamination that causes shrimp spoilage and economic losses to the shrimp industry. Different concentrations of an antimicrobial lipopeptide, the fermentation product of Bacillus subtilis, AMPNT-6, were tested for the ability to reduce adhesion and disrupt S. putrefaciens preformed biofilms on two different contact surfaces (shrimp shell, stainless steel sheet). AMPNT-6 displayed a marked dose- and time-dependent anti-adhesive effect>biofilm removal. 3MIC AMPNT-6 was able both to remove biofilm and prevent bacteria from forming biofilm in a 96-well polystyrene microplate used as the model surface. 2MIC AMPNT-6 prevented bacteria from adhering to the microplate surface to form biofilm for 3h and removed already existing biofilm within 24h. Secretion of extracellular polymeric substances incubated in LB broth for 24h by S. putrefaciens was minimal at 3× MIC AMPNT-6. Scanning electron microscopy showed that damage to S. putrefaciens bacteria by AMPNT-6 possibly contributed to the non-adherence to the surfaces. Disruption of the mature biofilm structure by AMPNT-6 contributed to biofilm removal. It is concluded that AMPNT-6 can be used effectively to prevent attachment and also detach S. putrefaciens biofilms from shrimp shells, stainless steel sheets and polystyrene surfaces. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stability of milk fat globule membrane proteins toward human enzymatic gastrointestinal digestion.

PubMed

Le, T T; Van de Wiele, T; Do, T N H; Debyser, G; Struijs, K; Devreese, B; Dewettinck, K; Van Camp, J

2012-05-01

The milk fat globule membrane (MFGM) fraction refers to the thin film of polar lipids and membrane proteins that surrounds fat globules in milk. It is its unique biochemical composition that renders MFGM with some beneficial biological activities, such as anti-adhesive effects toward pathogens. However, a prerequisite for the putative bioactivity of MFGM is its stability during gastrointestinal digestion. We, therefore, subjected MFGM material, isolated from raw milk, to an in vitro enzymatic gastrointestinal digestion. Sodium dodecyl sulfate PAGE, in combination with 2 staining methods, Coomassie Blue and periodic acid Schiff staining, was used to evaluate polypeptide patterns of the digest, whereas mass spectrometry was used to confirm the presence of specific MFGM proteins. Generally, it was observed that glycoproteins showed higher resistance to endogenous proteases compared with non-glycosylated proteins. Mucin 1 displayed the highest resistance to digestion and a considerable part of this protein was still detected at its original molecular weight after gastric and small intestine digestion. Cluster of differentiation 36 was also quite resistant to pepsin. A significant part of periodic acid Schiff 6/7 survived the gastric digestion, provided that the lipid moiety was not removed from the MFGM material. Overall, MFGM glycoproteins are generally more resistant to gastrointestinal digestion than serum milk proteins and the presence of lipids, besides glycosylation, may protect MFGM glycoproteins from gastrointestinal digestion. This gastrointestinal stability makes MFGM glycoproteins amenable to further studies in which their putative health-promoting effects can be explored. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Pharmacotherapeutical strategies in the prevention of acute, vaso-occlusive pain in sickle cell disease: a systematic review

PubMed Central

Mager, David J.; Davis, Shyrin C. A. T.; Biemond, Bart J.

2017-01-01

Sickle-cell disease (SCD) is characterized by frequent and painful vaso-occlusive crises (VOCs). Various treatments have been evaluated over the years. However, a clear overview is lacking. The objective of this study was to systematically review all pharmacotherapeutical strategies in the prevention of VOCs beyond hydroxyurea. We performed a systematic literature search (MEDLINE, Embase, CENTRAL). Eligible studies were controlled clinical trials evaluating pharmacotherapeutical interventions targeting the reduction of VOCs in patients with SCD. Primary outcomes were the number or duration of SCD-related pain days, VOCs, or hospital admissions for VOCs. Secondary outcomes included time to first VOC or hospital admission for a VOC. A standardized data extraction sheet was used. The methodological quality of studies was assessed using Cochrane’s risk-of-bias tool. A total of 36 studies were included in this review, covering 26 different prophylactic interventions. The most promising interventions for reducing the frequency of either VOCs or hospitalizations were the oral antioxidants l-glutamine and ω-3 fatty acids and the IV antiadhesive agent crizanlizumab. Twenty-three studies did not show any beneficial effect of the intervention under investigation, and 6 studies were either too small or methodologically inadequate to draw conclusions. Because of the heterogeneity of interventions, no meta-analysis was performed. In conclusion, this review identified 3 promising pharmacotherapeutical strategies in the prevention of VOCs in SCD. Importantly, this study highlights the discrepancy between the significant burden of SCD worldwide and the low number of adequate trials performed. This review was registered at PROSPERO (CRD42015025250). PMID:29296801

The expression of heterologous MAM-7 in Lactobacillus rhamnosus reduces its intrinsic capacity to inhibit colonization of pathogen Vibrio parahaemolyticus in vitro.

PubMed

Beltran, Sebastian; Munoz-Bergmann, Cristian A; Elola-Lopez, Ana; Quintana, Javiera; Segovia, Cristopher; Trombert, Annette N

2016-01-07

Vibrio parahaemolyticus (V. parahaemolyticus) is a Gram-negative, halophilic bacterium recognized as one of the most important foodborne pathogen. When ingested, V. parahaemolyticus causes a self-limiting illness (Vibriosis), characterized mainly by watery diarrhoea. Treatment is usually oral rehydration and/or antibiotics in complicated cases. Since 1996, the pathogenic and pandemic V. parahaemolyticus O3:K6 serotype has spread worldwide, increasing the reported number of vibriosis cases. Thus, the design of new strategies for pathogen control and illness prevention is necessary. Lactobacillus sp. grouped Gram positive innocuous bacteria, part of normal intestinal microbiota and usually used as oral vaccines for several diarrheic diseases. Recombinants strains of Lactobacillus (RL) expressing pathogen antigens can be used as part of an anti-adhesion strategy where RL block the pathogen union sites in host cells. Thus, we aimed to express MAM-7 V. parahaemolyticus adhesion protein in Lactobacillus sp. to generate an RL that prevents pathogen colonization. We cloned the MAM-7 gene from V. parahaemolyticus RIMD 2210633 in Lactobacillus expression vectors. Recombinant strains (Lactobacillus rhamnosus pSEC-MAM7 and L. rhamnosus pCWA-MAM7) adhered to CaCo-2 cells and competed with the pathogen. However, the L. rhamnosus wild type strain showed the best capacity to inhibit pathogen colonization in vitro. In addition, LDH-assay showed that recombinant strains were cytotoxic compared with the wild type isogenic strain. MAM-7 expression in lactobacilli reduces the intrinsic inhibitory capacity of L. rhamnosus against V. parahaemolyticus.

Effect of sodium hyaluronate/carboxymethyl cellulose (Guardix-sol) on retear rate and postoperative stiffness in arthroscopic rotator cuff repair patients: A prospective cohort study.

PubMed

Jeong, Jeung Yeol; Chung, Pill Ku; Yoo, Jae Chul

2017-01-01

Hyaluronate-based anti-adhesive agents are expected to enhance rotator cuff healing; however, their effect on the incidence and extent of postoperative complications such as stiffness and retears has not been investigated. From July 2012 to February 2013, 80 patients undergoing arthroscopic rotator cuff repair surgery were prospectively enrolled. Forty patients were assigned to the control group, while the other 40 were assigned to the injection group and received a Guardix-sol injection immediately after surgery. Passive range of motion, pain visual analog scale, and functional score were assessed at 8 weeks, 6 months, and 24 months postoperatively. Gliding motion between the deltoid muscle and the greater tuberosity of the proximal humerus was evaluated using ultrasonography at 2 and 8 weeks postoperatively, and tendon integrity was evaluated using magnetic resonance imaging at 6 months postoperatively. We found no significant difference between the groups regarding gliding motion at 2 weeks postoperatively. However, at 8 weeks, the incidence of poor gliding motion was 2.5% and 15% for the injected patients and control group, respectively, which was statistically significant. At 6 months after surgery, the retear rate between the two groups was not statistically significant. We found no statistically significant difference between the two groups regarding retear rate and clinical score throughout the follow-up period. We noted no complications related to the use of Guardix-sol. Patients who received the Guardix-sol injection showed improved gliding motion between the deltoid muscle and the greater tuberosity in the early postoperative period.

Natural Antimicrobials and Oral Microorganisms: A Systematic Review on Herbal Interventions for the Eradication of Multispecies Oral Biofilms.

PubMed

Karygianni, Lamprini; Al-Ahmad, Ali; Argyropoulou, Aikaterini; Hellwig, Elmar; Anderson, Annette C; Skaltsounis, Alexios L

2015-01-01

Oral diseases such as caries and periodontitis are mainly caused by microbial biofilms. Antibiotic therapy has reached its limits with regard to antimicrobial resistance, and new therapeutic measures utilizing natural phytochemicals are currently a focus of research. Hence, this systematic review provides a critical presentation of the antimicrobial effects of various medicinal herbs against in vitro, ex vivo, and in situ formed multispecies oral biofilms. Searches were performed in three English databases (PubMed, EMBASE, CAMbase) and the electronic archives of five German journals from the times of their establishment until October 10th, 2014, with the search terms "(plant extracts OR herbal extracts OR plant OR herb) AND (oral biofilm OR dental biofilm OR dental plaque OR oral disease OR dental disease)." The pooled data were assessed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA). Initially, 1848 articles were identified, out of which 585 full-text articles were screened, 149 articles were reevaluated for eligibility and finally, 14 articles met all inclusion criteria. The data of 14 reports disclosed enhanced antiadhesive and antibiofilm activity by the plant extracts obtained from Vitis vinifera, Pinus spp., Coffea canephora, Camellia sinensis, Vaccinium macrocarpon, Galla chinensis, Caesalpinia ferrea Martius, Psidium cattleianum, representative Brazilian plants and manuka honey. Overall, a positive correlation was revealed between herb-based therapies and elimination rates of all types of multispecies oral biofilms. In that context, integrating or even replacing conventional dental therapy protocols with herbal-inspired treatments can allow effective antimicrobial control of oral biofilms and thus, dental diseases.

Structure-Function Relationships of Human Milk Oligosaccharides123

PubMed Central

Bode, Lars; Jantscher-Krenn, Evelyn

2012-01-01

Human milk contains more than a hundred structurally distinct oligosaccharides. In this review, we provide examples of how the structural characteristics of these human milk oligosaccharides (HMO) determine functionality. Specific α1–2-fucosylated HMO have been shown to serve as antiadhesive antimicrobials to protect the breast-fed infant against infections with Campylobacter jejuni, one of the most common causes of bacterial diarrhea. In contrast, α1–2-fucosylation may abolish the beneficial effects of HMO against Entamoeba histolytica, a protozoan parasite that causes colitis, acute dysentery, or chronic diarrhea. In a different context, HMO need to be both fucosylated and sialylated to reduce selectin-mediated leukocyte rolling, adhesion, and activation, which may protect breast-fed infants from excessive immune responses. In addition, our most recent data show that a single HMO that carries not 1 but 2 sialic acids protects neonatal rats from necrotizing enterocolitis, one of the most common and often fatal intestinal disorders in preterm infants. Oligosaccharides currently added to infant formula are structurally different from the oligosaccharides naturally occurring in human milk. Thus, it appears unlikely that they can mimic some of the structure-specific effects of HMO. Recent advances in glycan synthesis and isolation have increased the availability of certain HMO tri- and tetrasaccharides for in vitro and in vivo preclinical studies. In the end, intervention studies are needed to confirm that the structure-specific effects observed at the laboratory bench translate into benefits for the human infant. Ultimately, breastfeeding remains the number one choice to nourish and nurture our infants. PMID:22585916

Effect of oligosaccharides on the adhesion of gut bacteria to human HT-29 cells.

PubMed

Altamimi, M; Abdelhay, O; Rastall, R A

2016-06-01

The influence of five oligosaccharides (cellobiose, stachyose, raffinose, lactulose and chito-oligosaccharides) on the adhesion of eight gut bacteria (Bifidobacterium bifidum ATCC 29521, Bacteroides thetaiotaomicron ATCC 29148D-5, Clostridium leptum ATCC 29065, Blautia coccoides ATCC 29236, Faecalibacterium prausnitzii ATCC 27766, Bacteroides fragilis ATCC 23745, Clostridium difficile ATCC 43255 and Lactobacillus casei ATCC 393) to mucous secreting and non-mucous secreting HT-29 human epithelial cells, was investigated. In pure culture, the bacteria showed variations in their ability to adhere to epithelial cells. The effect of oligosaccharides diminished adhesion and the presence of mucus played a major factor in adhesion, likely due to high adhesiveness to mucins present in the native human mucus layer covering the whole cell surface. However, clostridia displayed almost the same level of adhesion either with or without mucus being present. Bl. coccoides adhesion was decreased by stachyose and cellobiose in non-mucus-secreting cells in pure culture, while in mixed faecal culture cellobiose displayed the highest antiadhesive activity with an overall average of 65% inhibition amongst tested oligomers and lactulose displayed the lowest with an average of 47.4%. Bifidobacteria, Bacteroides, lactobacilli and clostridia were inhibited within the following ranges 47-78%, 32-65%, 11.7-58% and 64-85% respectively. This means that clostridia were the most strongly influenced members of the microflora amongst the bacterial groups tested in mixed culture. In conclusion, introducing oligosaccharides which are candidate prebiotics into pure or mixed cultures has affected bacterial adhesion. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cholesteryl butyrate solid lipid nanoparticles inhibit adhesion of human neutrophils to endothelial cells

PubMed Central

Dianzani, Chiara; Cavalli, Roberta; Zara, Gian Paolo; Gallicchio, Margherita; Lombardi, Grazia; Gasco, Maria Rosa; Panzanelli, Patrizia; Fantozzi, Roberto

2006-01-01

Adhesion of polymorphonuclear cells (PMNs) to vascular endothelial cells (EC) is a critical step in recruitment and infiltration of leukocytes into tissues during inflammation. High doses of butyric acid have been shown to ameliorate inflammation in inflammatory bowel diseases (IBD). Cholesteryl-butyrate solid lipid nanoparticles (chol-but SLN) as prodrug are a possible delivery system for butyric acid. Sodium butyrate or chol-but SLN were coincubated with human PMNs and human umbilical vein EC (HUVEC); adhesion was quantified by computerized microimaging fluorescence analysis. Both chol-but SLN and sodium butyrate displayed antiadhesive effects on FMLP- and IL-1β-stimulated cells in a concentration–response curve (10−8–10−5 M), but chol-but SLN were in all cases more active. Moreover, chol-but SLN inhibited FMLP-induced adhesion of PMNs to FCS-coated plastic wells, thus showing a direct effect on PMNs, while sodium butyrate had little effect. Confocal microscopy showed that fluorescent SLN entered PMNs and HUVEC after 10 min incubation. Chol-but SLN acted either on activated PMN or HUVEC. Chol-but SLN inhibited O2−· production and myeloperoxidase release by PMNs evoked by FMLP, in a dose-dependent, but not time-dependent, manner and were more active than sodium butyrate. In conclusion, in all tests chol-but SLN were more active than sodium butyrate. Thus, chol-but SLN might be a valid alternative to sodium butyrate in the anti-inflammatory therapy of ulcerative colitis, avoiding complications related to the administration of sodium butyrate. PMID:16702992

Combustion products of plastics as indicators for refuse burning in the atmosphere.

PubMed

Simoneit, Bernd R T; Medeiros, Patricia M; Didyk, Borys M

2005-09-15

Despite all of the economic problems and environmental discussions on the dangers and hazards of plastic materials, plastic production worldwide is growing at a rate of about 5% per year. Increasing techniques for recycling polymeric materials have been developed during the last few years; however, a large fraction of plastics are still being discarded in landfills or subjected to intentional or incidental open-fire burning. To identify specific tracer compounds generated during such open-fire combustion, both smoke particles from burning and plastic materials from shopping bags, roadside trash, and landfill garbage were extracted for gas chromatography-mass spectrometry analyses. Samples were collected in Concón, Chile, an area frequently affected by wildfire incidents and garbage burning, and the United States for comparison. Atmospheric samples from various aerosol sampling programs are also presented as supportive data. The major components of plastic extracts were even-carbon-chain n-alkanes (C16-C40), the plasticizer di-2-ethylhexyl phthalate, and the antioxidants and lubricants/antiadhesives Irganox 1076, Irgafos 168, and its oxidation product tris(2,4-di-tertbutylphenyl) phosphate. Major compounds in smoke from burning plastics include the non-source-specific n-alkanes (mainly even predominance), terephthalic acid, phthalates, and 4-hydroxybenzoic acid, with minor amounts of polycyclic aromatic hydrocarbons (including triphenylbenzenes) and tris(2,4-di-tert-butylphenyl)phosphate. 1,3,5-Triphenylbenzene and tris(2,4-di-tert-butylphenyl)- phosphate were found in detectable amounts in atmospheric samples where plastics and refuse were burned in open fires, and thus we propose these two compounds as specific tracers for the open-burning of plastics.

Interference in adhesion of bacteria and yeasts isolated from explanted voice prostheses to silicone rubber by rhamnolipid biosurfactants.

PubMed

Rodrigues, L R; Banat, I M; van der Mei, H C; Teixeira, J A; Oliveira, R

2006-03-01

The effects and extent of adhesion of four different bacterial and two yeast strains isolated from explanted voice prostheses to silicone rubber with and without an adsorbed rhamnolipid biosurfactant layer obtained from Pseudomonasaeruginosa DS10-129 was studied. The ability of rhamnolipid biosurfactant to inhibit adhesion of micro-organisms to silicone rubber was investigated in a parallel-plate flow chamber. The anti-adhesive activity of the biosurfactant at different concentrations was significant against all the strains and depended on the micro-organism tested. The results showed an effective reduction in the initial deposition rates, and the number of bacterial cells adhering after 4 h, for all micro-organisms tested at the 4 g l(-1) undiluted rhamnolipid solution. Maximum initial reduction of adhesion rate (an average of 66%) occurred for Streptococcus salivarius GB 24/9 and Candida tropicalis GB 9/9. The number of cells adhering after 4 h on silicone rubber conditioned with biosurfactant was reduced to 48% for Staphylococcus epidermidis GB 9/6, Strep. salivarius GB 24/9, Staphylococcus aureus GB 2/1 and C. tropicalis GB 9/9 in comparison to controls. Perfusing the flow chamber with biosurfactant containing solution followed by the passage of a liquid-air interface, to investigate detachment of micro-organisms adhering to silicone rubber, produced high detachment (96%) of adhered cells for all micro-organisms studied, except for Staph. aureus GB 2/1 (67%). It is concluded that biosurfactant represent suitable compounds that should be considered in developing future strategies to prevent the microbial colonization of silicone rubber voice prostheses.

Assessment of adhesion formation after laparoscopic intraperitoneal implantation of Dynamesh IPOM mesh

PubMed Central

Jałyński, Marek; Piskorz, Łukasz; Brocki, Marian

2013-01-01

Introduction Formation of adhesions after laparoscopic hernia repair using the intra-peritoneal onlay mesh (IPOM) procedure can lead to intestinal obstruction or mesh erosion into intestinal lumen. The aims of this study included: measurement of adhesion formation with Dynamesh IPOM after laparoscopic intraperitoneal implantation, and assessment of the occurrence of isolated adhesions at the fastening sites of slowly absorbable sutures. Material and methods Twelve healthy pigs underwent laparoscopic implantation of 2 Dynamesh IPOM mesh fragments each, one was fastened with PDSII, and the other with Maxon sutures. An assessment of adhesion formation was carried out after 6 weeks and included an evaluation of surface area, hardness according to the Zhulke scale, and index values. The occurrence of isolated adhesions at slowly absorbable suture fixation points was also analyzed. Results Adhesions were noted in 83.3% of Dynamesh IPOM meshes. Adhesions covered on average 37.7% of the mesh surface with mean hardness 1.46 and index value 78.8. In groups fixed with PDS in comparison to Maxon sutures adhesions covered mean 31.6% vs. 42.5% (p = 0.62) of the mesh surface, mean hardness was 1.67 vs.1.25 (p = 0.34) and index 85.42 vs. 72.02 (p = 0.95). Conclusions The Dynamesh IPOM mesh, in spite of its anti-adhesive layer of PVDF, does not prevent the formation of adhesions. Adhesion hardness, surface area, and index values of the Dynamesh IPOM mesh are close to the mean values of these parameters for other commercially available 2-layer meshes. Slowly absorbable sutures used for fastening did not increase the risk of adhesion formation. PMID:23847671

Inflammatory pathways of importance for management of inflammatory bowel disease.

PubMed

Pedersen, Jannie; Coskun, Mehmet; Soendergaard, Christoffer; Salem, Mohammad; Nielsen, Ole Haagen

2014-01-07

Inflammatory bowel disease (IBD) is a group of chronic disorders of the gastrointestinal tract comprising Crohn's disease (CD) and ulcerative colitis (UC). Their etiologies are unknown, but they are characterised by an imbalanced production of pro-inflammatory mediators, e.g., tumor necrosis factor (TNF)-α, as well as increased recruitment of leukocytes to the site of inflammation. Advantages in understanding the role of the inflammatory pathways in IBD and an inadequate response to conventional therapy in a large portion of patients, has over the last two decades lead to new therapies which includes the TNF inhibitors (TNFi), designed to target and neutralise the effect of TNF-α. TNFi have shown to be efficient in treating moderate to severe CD and UC. However, convenient alternative therapeutics targeting other immune pathways are needed for patients with IBD refractory to conventional therapy including TNFi. Indeed, several therapeutics are currently under development, and have shown success in clinical trials. These include antibodies targeting and neutralising interleukin-12/23, small pharmacologic Janus kinase inhibitors designed to block intracellular signaling of several pro-inflammatory cytokines, antibodies targeting integrins, and small anti-adhesion molecules that block adhesion between leukocytes and the intestinal vascular endothelium, reducing their infiltration into the inflamed mucosa. In this review we have elucidated the major signaling pathways of clinical importance for IBD therapy and highlighted the new promising therapies available. As stated in this paper several new treatment options are under development for the treatment of CD and UC, however, no drug fits all patients. Hence, optimisations of treatment regimens are warranted for the benefit of the patients either through biomarker establishment or other rationales to maximise the effect of the broad range of mode-of-actions of the present and future drugs in IBD.

Safety and Efficacy of Alginate Adhesion Barrier Gel in Compromised Intestinal Anastomosis.

PubMed

Chaturvedi, Ankit A; Yauw, Simon T K; Lomme, Roger M L M; Hendriks, Thijs; van Goor, Harry

For any anti-adhesive barrier developed for abdominal surgery, the use under conditions in which anastomotic healing is compromised needs to be investigated. The current study evaluates the effect of a new ultrapure alginate gel on early healing of high-risk anastomoses in the ileum and compares this with the gold standard used in clinical practice. In 75 adult male Wistar rats, a 5 mm ileal segment was resected and continuity was restored by construction of an inverted anastomosis. Rats were divided randomly into a control group and groups receiving either alginate gel or a sodium hyaluronate carboxymethylcellulose (HA/CMC) film around the anastomosis (n = 25 each). Carprofen, given in a daily dose of 1.25 mg/kg, was used to compromise anastomotic healing. At day three, animals were killed and scored for signs of anastomotic leakage and the presence of adhesions. The incidence of adhesion formation was 95% in the HA/CMC film group, which was significantly higher than in the controls (64%, p = 0.010) and the alginate gel group (52%, p = 0.004). The adhesion score was nearly 40% lower in the alginate gel group compared with the HA/CMC film group. The incidence of ileal leakage in the HA/CMC film group (92%) was significantly higher than in the controls (68%, p = 0.016). Leakage rate did not differ between the alginate gel and control groups. There was no significant difference between groups in either incision bursting pressure or incision breaking strength. Ultrapure alginate gel does not interfere with repair of ileal anastomoses constructed under conditions in which chances of anastomotic dehiscence are high. The alginate gel performs better than the HA/CMC film.

Single-Port Onlay Mesh Repair of Recurrent Inguinal Hernias after Failed Anterior and Laparoscopic Repairs

PubMed Central

Tran, Kim; Zajkowska, Marta; Lam, Vincent; Hawthorne, Wayne J.

2015-01-01

Background and Objectives: Despite the exponential increase in the use of laparoscopic inguinal herniorrhaphy, overall recurrence rates have remained unchanged. Therefore, a growing number of patients are presenting with recurrent hernias after conventional anterior and laparoscopic repairs have failed. This study reports our experience with single-incision laparoscopic (SIL) intraperitoneal onlay mesh (IPOM) repair of these hernias. Methods: Patients referred with two or more recurrences of inguinal hernia underwent SIL-IPOM from November 1, 2009, to June 24, 2014. A 2.5-cm infraumbilical incision was made, and an SIL port was placed intraperitoneally. Modified dissection techniques were used: chopstick and inline dissection, 5.5-mm/52-cm/30° angled laparoscope, and conventional straight dissecting instruments. The peritoneum was incised above the pubic symphysis, and dissection was continued laterally and proximally, raising the inferior flap below the previous extraperitoneal mesh while reducing any direct, indirect, femoral, or cord lipoma before placement of antiadhesive mesh, which was fixed to the pubic ramus, as well as superiorly, with nonabsorbable tacks before the inferior border was fixed with fibrin sealant. The inferior peritoneal flap was then tacked back onto the mesh. Results: Nine male patients underwent SIL-IPOM. Their mean age was 53 years and mean body mass index was 26.8 kg/m2. Mean mesh size was 275 cm2. Mean operation time was 125 minutes, with a hospital stay of 1 day. The umbilical scar length was 23 mm at the 6-week follow-up. There were no intra-/postoperative complications, port-site hernias, chronic groin pain, or recurrence of the hernia during a mean follow-up of 24 months. Conclusion: Inguinal hernias recurring after two or more failed conventional anterior and laparoscopic repairs can be safely and efficiently treated with SIL-IPOM. PMID:25848186

Single-Incision Laparoscopic Intraperitoneal Onlay Mesh Repair for the Treatment of Multiple Recurrent Inguinal Hernias

PubMed Central

Tran, Kim; Zajkowska, Marta; Lam, Vincent; Hawthorne, Wayne

2014-01-01

Introduction: Despite an exponential rise in laparoscopic surgery for inguinal herniorrhaphy, overall recurrence rates have remained unchanged. Therefore, an increasing number of patients present with recurrent hernias after having failed anterior and laparoscopic repairs. This study reports our experience with single-incision laparoscopic (SIL) intraperitoneal onlay mesh (IPOM) repair for these hernias. Materials and methods: All patients referred with multiply recurrent inguinal hernias underwent SIL-IPOM from November 1 2009 to October 30 2013. A 2.5-cm infraumbilical incision was made and a SIL surgical port was placed intraperitoneally. Modified dissection techniques, namely, “chopsticks” and “inline” dissection, 5.5 mm/52 cm/30° angled laparoscope and conventional straight dissecting instruments were used. The peritoneum was incised above the symphysis pubis and dissection continued laterally and proximally raising an inferior flap, below a previous extraperitoneal mesh, while reducing any direct/indirect/femoral/cord lipoma before placement of antiadhesive mesh that was fixed into the pubic ramus as well as superiorly with nonabsorbable tacks before fixing its inferior border with fibrin sealant. The inferior peritoneal flap was then tacked back onto the mesh. Results: There were 9 male patients who underwent SIL-IPOM. Mean age was 55 years old and mean body mass index was 26.8 kg/m2. Mean mesh size was 275 cm2. Mean operation time was 125 minutes with hospital stay of 1 day and umbilical scar length of 21 mm at 4 weeks' follow-up. There were no intraoperative/postoperative complications, port-site hernias, chronic groin pain, or recurrence with mean follow-up of 20 months. Conclusions: Multiply recurrent inguinal hernias after failed conventional anterior and laparoscopic repairs can be treated safely and efficiently with SIL-IPOM. PMID:25392643

A belgian multicenter prospective observational cohort study shows safe and efficient use of a composite mesh with incorporated oxidized regenerated cellulose in laparoscopic ventral hernia repair.

PubMed

Berrevoet, F; Tollens, T; Berwouts, L; Bertrand, C; Muysoms, F; De Gols, J; Meir, E; De Backer, A

2014-01-01

A variety of anti-adhesive composite mesh products have become available to use inside the peritoneal cavity. However, reimbursement of these meshes by the Belgian Governemental Health Agency (RIZIV/INAMI) can only be obtained after conducting a prospective study with at least one year of clinical follow-up. This -Belgian multicentric cohort study evaluated the experience with the use of Proceed®-mesh in laparoscopic ventral hernia repair. During a 25 month period 210 adult patients underwent a laparoscopic primary or incisional hernia repair using an intra-abdominal placement of Proceed®-mesh. According to RIZIV/INAMI criteria recurrence rate after 1 year was the primary objective, while postoperative morbidity, including seroma formation, wound and mesh infections, quality of life and recurrences after 2 years were evaluated as secondary endpoints (NCT00572962). In total 97 primary ventral and 103 incisional hernias were repaired, of which 28 (13%) were recurrent. There were no conversions to open repair, no enterotomies, no mesh infections and no mortality. One year cumulative follow-up showed 10 recurrences (n = 192, 5.2%) and chronic discomfort or pain in 4.7% of the patients. Quality of life could not be analyzed due to incomplete data set. More than 5 years after introduction of this mesh to the market, this prospective multicentric study documents a favorable experience with the Proceed mesh in laparoscopic ventral hernia repair. However, it remains to be discussed whether reimbursement of these meshes in Belgium should be limited to the current strict criteria and therefore can only be obtained after at least 3-4 years of clinical data gathering and necessary follow-up. Copyright© Acta Chirurgica Belgica.

Impaired ATP release from red blood cells promotes their adhesion to endothelial cells: A mechanism of hypoxemia after transfusion

PubMed Central

Zhu, Hongmei; Zennadi, Rahima; Xu, Bruce X.; Eu, Jerry P.; Torok, Jordan A.; Telen, Marilyn J.; McMahon, Timothy J.

2011-01-01

Objective Transfusion of red blood cells (RBCs) has been linked to disappointing clinical outcomes in the critically ill, but specific mechanisms of organ dysfunction after transfusion remain poorly understood. We tested the hypothesis that RBC storage impairs the ability of RBCs to release ATP and that impaired ATP-release was injurious in vivo, in part through increased RBC adhesion. Design Prospective, controlled, mechanistic study. Setting University research laboratory. Subjects Human and mouse blood donors; nude mouse transfusion recipients. Interventions Manipulation of ATP release, supplemental ATP, and antibodies to RBC and endothelial adhesion receptors were used in vitro and in vivo to probe the roles of released ATP and adhesion in responses to (transfused) RBCs. Measurements and main results The ability of stored RBCs to release ATP declined markedly within 14 days after collection, despite relatively stable levels of ATP within the RBCs. Inhibiting ATP release promoted the adhesion of stored RBCs to endothelial cells in vitro and RBC sequestration in the lungs of transfused mice in vivo. Unlike transfusion of fresh human RBCs, stored-RBC transfusion in mice decreased blood oxygenation and increased extravasation of RBCs into the lung’s alveolar airspaces. Similar findings were seen with transfusion of fresh RBCs treated with the ATP-release inhibitors glibenclamide and carbenoxolone. These findings were prevented by either co-infusion of an ATP analog or pre-transfusion incubation of the RBCs with an antibody against the erythrocyte adhesion receptor LW (Landsteiner-Wiener; ICAM-4). Conclusions The normal flow of RBCs in pulmonary microvessels depends in part on the release of anti-adhesive ATP from RBCs, and storage-induced deficiency in ATP release from transfused RBCs may promote or exacerbate microvascular pathophysiology in the lung, in part through increased RBC adhesion. PMID:21765360

Pre-hatching embryo-dependent and -independent programming of endometrial function in cattle

PubMed Central

Sponchiado, Mariana; Gomes, Nathália Souza; Fontes, Patrícia Kubo; Martins, Thiago; del Collado, Maite; Pastore, Athos de Assumpção; Pugliesi, Guilherme; Nogueira, Marcelo Fábio Gouveia

2017-01-01

The bovine pre-implantation embryo secretes bioactive molecules from early development stages, but effects on endometrial function are reported to start only after elongation. Here, we interrogated spatially defined regions of the endometrium transcriptome for responses to a day 7 embryo in vivo. We hypothesize that exposure to an embryo changes the abundance of specific transcripts in the cranial region of the pregnant uterine horn. Endometrium was collected from the uterotubal junction (UTJ), anterior (IA), medial (IM) and posterior (IP) regions of the uterine horn ipsilateral to the CL 7 days after estrus from sham-inseminated (Con) or artificially inseminated, confirmed pregnant (Preg) cows. Abundance of 86 transcripts was evaluated by qPCR using a microfluidic platform. Abundance of 12 transcripts was modulated in the Preg endometrium, including classical interferon-stimulated genes (ISG15, MX1, MX2 and OAS1Y), prostaglandin biosynthesis genes (PTGES, HPGD and AKR1C4), water channel (AQP4) and a solute transporter (SLC1A4) and this was in the UTJ and IA mainly. Additionally, for 71 transcripts, abundance varied according to region of the reproductive tract. Regulation included downregulation of genes associated with proliferation (IGF1, IGF2, IGF1R and IGF2R) and extracellular matrix remodeling (MMP14, MMP19 and MMP2) and upregulation of anti-adhesive genes (MUC1) in the cranial regions of uterine horn. Physical proximity to the embryo provides paracrine regulation of endometrial function. Embryo-independent regulation of the endometrial transcriptome may support subsequent stages of embryo development, such as elongation and implantation. We speculate that successful early embryo-dependent and -independent programming fine-tune endometrial functions that are important for maintenance of pregnancy in cattle. PMID:28423001

Evaluation of Lactic Acid Bacteria Isolated from Fermented Plant Products for Antagonistic Activity Against Urinary Tract Pathogen Staphylococcus saprophyticus.

PubMed

Tsai, Cheng-Chih; Lai, Tzu-Min; Lin, Pei-Pei; Hsieh, You-Miin

2018-06-01

Urinary tract infections (UTIs) are the most common infectious diseases in infants and the elderly; they are also the most common among nosocomial infections. The treatment of UTIs usually involves a short-term course of antibiotics. The purpose of this study was to identify the strains of lactic acid bacteria (LAB) that can inhibit the urinary tract pathogen Staphylococcus saprophyticus, as alternatives to antibiotics. In this study, we collected 370 LAB strains from fermented plant products and reference strains from the Bioresources Collection and Research Center (BCRC). Using spent culture supernatants (SCS), we then screened these LAB strains with for antimicrobial effects on urinary tract pathogens by the well-diffusion assay. Seven LAB strains-PM2, PM68, PM78, PM201, PM206, PM229, and RY2-exhibited inhibitory activity and were evaluated for anti-growth activity against urinary tract pathogens by the co-culture inhibition assay. Anti-adhesion and anti-invasion activities against urinary tract pathogens were evaluated using the SV-HUC-1 urothelial cell cultures. The results revealed that the survival rate of S. saprophyticus ranged from 0.9-2.96%, with the pH continuously decreasing after co-culture with LAB strains for 4 h. In the competitive adhesion assay, the exclusion and competition groups performed better than the displacement group. In the SV-HUC-1 cell invasion assay, PM201, PM206, PM229, and RY2 were found to inhibit the invasion of SV-HUC-1 cells by S. saprophyticus BCRC 10786. To conclude, RY2, PM229, and PM68 strains exhibited inhibitory activity against the urinary tract pathogen S. saprophyticus.

Plasmodium falciparum-induced CD36 clustering rapidly strengthens cytoadherence via p130CAS-mediated actin cytoskeletal rearrangement

PubMed Central

Davis, Shevaun P.; Amrein, Matthias; Gillrie, Mark R.; Lee, Kristine; Muruve, Daniel A.; Ho, May

2012-01-01

The adhesion of infected red blood cells (IRBCs) to microvascular endothelium is critical in the pathogenesis of severe malaria. Here we used atomic force and confocal microscopy to examine the adhesive forces between IRBCs and human dermal microvascular endothelial cells. Initial contact of the cells generated a mean ± sd adhesion force of 167 ± 208 pN from the formation of single or multiple bonds with CD36. The strength of adhesion increased by 5- to 6-fold within minutes of contact through a signaling pathway initiated by CD36 ligation by live IRBCs, or polystyrene beads coated with anti-CD36 or PpMC-179, a recombinant peptide representing the minimal binding domain of the parasite ligand PfEMP1 to CD36. Engagement of CD36 led to localized phosphorylation of Src family kinases and the adaptor protein p130CAS, resulting in actin recruitment and CD36 clustering by 50–60% of adherent beads. Uninfected red blood cells or IgG-coated beads had no effect. Inhibition of the increase in adhesive strength by the Src family kinase inhibitor PP1 or gene silencing of p130CAS decreased adhesion by 39 ± 12 and 48 ± 20%, respectively, at 10 dyn/cm2 in a flow chamber assay. Modulation of adhesive strength at PfEMP1-CD36-actin cytoskeleton synapses could be a novel target for antiadhesive therapy.—Davis, S. P., Amrein, M., Gillrie, M. R., Lee, K., Muruve, D. A., Ho, M. Plasmodium falciparum-induced CD36 clustering rapidly strengthens cytoadherence via p130CAS-mediated actin cytoskeletal rearrangement. PMID:22106368

Release of Membrane-Bound Vesicles and Inhibition of Tumor Cell Adhesion by the Peptide Neopetrosiamide A

PubMed Central

Austin, Pamela; Heller, Markus; Williams, David E.; McIntosh, Lawrence P.; Vogl, A. Wayne; Foster, Leonard J.; Andersen, Raymond J.; Roberge, Michel; Roskelley, Calvin D.

2010-01-01

Background Neopetrosiamide A (NeoA) is a 28-amino acid tricyclic peptide originally isolated from a marine sponge as a tumor cell invasion inhibitor whose mechanism of action is unknown. Methodology/Principal Findings We show that NeoA reversibly inhibits tumor cell adhesion, disassembles focal adhesions in pre-attached cells, and decreases the level of β1 integrin subunits on the cell surface. NeoA also induces the formation of dynamic, membrane-bound protrusions on the surface of treated cells and the release of membrane-bound vesicles into the culture medium. Proteomic analysis indicates that the vesicles contain EGF and transferrin receptors as well as a number of proteins involved in adhesion and migration including: β1 integrin and numerous α integrin subunits; actin and actin-binding proteins such as cofilin, moesin and myosin 1C; and membrane modulating eps15 homology domain (EHD) proteins. Surface labeling, trafficking inhibition, and real-time imaging experiments all suggest that β1 integrin-containing vesicles are released directly from NeoA-induced cell surface protrusions rather than from vesicles generated intracellularly. The biological activity of NeoA is dependent on its disulfide bond pattern and NMR spectroscopy indicates that the peptide is globular with a continuous ridge of hydrophobic groups flanked by charged amino acid residues that could facilitate a simultaneous interaction with lipids and proteins in the membrane. Conclusions/Significance NeoA is an anti-adhesive peptide that decreases cell surface integrin levels through a novel, yet to be elucidated, mechanism that involves the release of adhesion molecule-containing vesicles from the cell surface. PMID:20520768

Ameliorating effects of fluorocarbon emulsion on sickle red blood cell-induced obstruction in an ex vivo vasculature.

PubMed

Kaul, D K; Liu, X; Nagel, R L

2001-11-15

In sickle cell (SS) vaso-occlusion, the culminating event is blockage of blood vessels by sickled red blood cells (SS RBCs). As shown in animal models, SS RBC-induced vaso-occlusion is often partial, allowing for a residual flow, hence oxygen delivery to partially occluded vessels could reduce vaso-occlusion. The efficacy of an oxygenated perflubron-based fluorocarbon emulsion (PFE) was tested for its anti-vaso-occlusive effects in the ex vivo mesocecum vasculature of the rat. Microvascular obstruction was induced by the infusion of deoxygenated SS RBCs into ex vivo preparations with or without pretreatment with platelet-activating factor (PAF). PAF induced enhanced SS RBC-endothelium interactions, leading to greater vaso-occlusion. Microvascular blockage resulted in increased peripheral resistance units (PRU). Deoxygenated SS RBCs caused a persistent 1.5-fold PRU increase in untreated preparations and approximately a 2-fold PRU increase in PAF-treated preparations. The greater PRU in PAF-treated preparations was caused by widespread adhesion and postcapillary blockage. Oxygenated PFE, but not deoxygenated PFE, resulted in PRU decreases to baseline values in both groups of experiments (with or without PAF). The PRU decrease caused by oxygenated PFE infusion was caused by unsickling of SS RBCs in partially occluded vessels, with no antiadhesive effect on already adherent SS RBCs as assessed by intravital microscopy. PFE had no effect on vascular tone. The efficacy of PFE appears to result from its greater capacity to dissolve oxygen (10-fold higher than plasma). The dislodgement of trapped SS RBCs and an increase in wall shear rates will help reverse the partial obstruction. Thus, oxygenated PFE is capable of reducing SS RBC-induced vaso-occlusion, and further development of this approach is advisable.

Clinical observation of fallopian tube obstruction recanalization by ozone

PubMed Central

Sun, Niuniu; Wei, Lequn; Chen, Diansen; Gao, Wanqin; Niu, Huanzhang; He, Chao

2017-01-01

Objective: To investigate the clinical effect of fallopian tube obstruction recanalization by ozone. Methods: Total 116 cases of patients undergoing the fallopian tube obstruction were randomly divided into the experimental group and control group, with 58 cases in each group. All patients underwent the interventional fallopian tube recanalization. The patients in the experimental group underwent the fallopian tube perfusion by the ozone water. Meanwhile, the patients in the control group were treated with the conventional anti-inflammatory and anti-adhesion drugs. After the follow-up visit for 6 months, the pregnancy rate and fallopian tube re-occlusion rate were counted and compared between the two groups. Meanwhile, the symptoms were evaluated and compared between the two groups after the operation for two weeks. Results: The success rate of fallopian tube recanalization was 93.1% (54/58), the pregnancy rate was 79.3% (46/58) and the recurrence rate was 5.2% (3/58) in the experimental group. While the success rate of fallopian tube recanalization was 91.4% (53/58), the pregnancy rate was 60.3% (35/58) and the recurrence rate was 17.2% (10/58) in the control group. Analysis showed that there was no significant difference in the recanalization success rate between the two groups (P>0.05). However, the pregnancy rate and re-occlusion rate in the experimental group were significantly lower than those of the control group (P<0.05), and the difference was statistically significant. There was no significant difference in the discomfort symptoms between the experimental group and control group (P>0.05). Conclusion: Fallopian tube recanalization by ozone perfusion can effectively increase the postoperative pregnancy rate and reduce the fallopian tube re-occlusion. PMID:28523024

Evaluation of the effects of hyaluronic acid-carboxymethyl cellulose barrier on ovarian tumor progression

PubMed Central

2014-01-01

Background Hyaluronic acid is a prognostic factor in ovarian cancers. It is also a component of Hyaluronic Acid-Carboxymethyl Cellulose (HA-CMC) barrier, an anti-adhesion membrane widely used during abdominal surgeries in particular for ovarian carcinosis. 70% of patients who undergo ovarian surgery will relapse due to the persistence of cancer cells. This study’s objective was to determine the oncological risk from use of this material, in the presence of residual disease, despite the benefit gained by it decreasing post-surgical adhesions in order to provide an unambiguous assessment of its appropriateness for use in ovarian surgical management. Methods We assessed the effects of HA-CMC barrier on the in vitro proliferation of human ovarian tumor cell lines (OVCAR-3, IGROV-1 and SKOV-3). We next evaluated, in vivo in nude mice, the capacity of this biomaterial to regulate the tumor progression of subcutaneous and intraperitoneal models of ovarian tumor xenografts. Results We showed that HA-CMC barrier does not increase in vitro proliferation of ovarian cancer cell lines compared to control. In vivo, HA-CMC barrier presence with subcutaneous xenografts induced neither an increase in tumor volume nor cell proliferation (Ki67 and mitotic index). With the exception of an increased murine carcinosis score in peritoneum, the presence of HA-CMC barrier with intraperitoneal xenografts modified neither macro nor microscopic tumor growth. Finally, protein analysis of survival (Akt), proliferation (ERK) and adhesion (FAK) pathways highlighted no activation on the xenografts imputable to HA-CMC barrier. Conclusions For the most part, our results support the lack of tumor progression activation due to HA-CMC barrier. We conclude that the benefits gained from using HA-CMC barrier membrane during ovarian cancer surgeries seem to outweigh the potential oncological risks. PMID:24739440

Analysis of postoperative complications associated with the use of anti-adhesion sodium hyaluronate-carboxymethylcellulose (HA-CMC) barrier after cytoreductive surgery for ovarian, fallopian tube and peritoneal cancers.

PubMed

Krill, Lauren S; Ueda, Stefanie M; Gerardi, Melissa; Bristow, Robert E

2011-02-01

To evaluate the risk of postoperative complications related to HA-CMC use in patients undergoing optimal cytoreductive surgery for primary and recurrent ovarian, fallopian tube, and peritoneal cancers. A single institution retrospective review identified all patients undergoing optimal (≤1 cm) cytoreductive surgery for primary or recurrent ovarian, fallopian tube, and peritoneal cancers between 1/95 and 12/08. Operative details and post-operative complications (<30 days) were extracted from the medical record. Fisher's exact test, Mann-Whitney-U, and multiple regression analyses were performed to identify factors, including HA-CMC use, associated with post-operative complications. Three hundred seventy-five cases were analyzed: HA-CMC was utilized in 168 debulking procedures. There was no difference in the incidence of overall morbidity for patients with HA-CMC compared to those without HA-CMC (OR 1.07; 95% CI: 0.68-1.67). On univariate analysis, application of HA-CMC increased the risk of pelvic abscess (OR 2.66; 95% CI: 1.21-5.86), particularly in the primary surgery setting (OR 4.65; 95% CI: 1.67-12.98) and in patients undergoing hysterectomy (OR 3.36; 95% CI: 1.18-9.53). After controlling for confounding factors using multiple linear regression, HA-CMC use approached statistical significance in predicting an increased risk of pelvic abscess but not major postoperative morbidity. HA-CMC adhesion barrier placement at the time of optimal cytoreductive surgery for ovarian, fallopian tube, and peritoneal cancer is not associated with major postoperative complications but may be associated with increased risk of pelvic abscess. Copyright © 2010 Elsevier Inc. All rights reserved.

Cholesteryl butyrate solid lipid nanoparticles inhibit the adhesion and migration of colon cancer cells

PubMed Central

Minelli, R; Serpe, L; Pettazzoni, P; Minero, V; Barrera, G; Gigliotti, CL; Mesturini, R; Rosa, AC; Gasco, P; Vivenza, N; Muntoni, E; Fantozzi, R; Dianzani, U; Zara, GP; Dianzani, C

2012-01-01

BACKGROUND AND PURPOSE Cholesteryl butyrate solid lipid nanoparticles (cholbut SLN) provide a delivery system for the anti-cancer drug butyrate. These SLN inhibit the adhesion of polymorphonuclear cells to the endothelium and may act as anti-inflammatory agents. As cancer cell adhesion to endothelium is crucial for metastasis dissemination, here we have evaluated the effect of cholbut SLN on adhesion and migration of cancer cells. EXPERIMENTAL APPROACH Cholbut SLN was incubated with a number of cancer cell lines or human umbilical vein endothelial cells (HUVEC) and adhesion was quantified by a computerized micro-imaging system. Migration was detected by the scratch ‘wound-healing’ assay and the Boyden chamber invasion assay. Expression of ERK and p38 MAPK was analysed by Western blot. Expression of the mRNA for E-cadherin and claudin-1 was measured by RT-PCR. KEY RESULTS Cholbut SLN inhibited HUVEC adhesiveness to cancer cell lines derived from human colon–rectum, breast, prostate cancers and melanoma. The effect was concentration and time-dependent and exerted on both cancer cells and HUVEC. Moreover, these SLN inhibited migration of cancer cells and substantially down-modulated ERK and p38 phosphorylation. The anti-adhesive effect was additive to that induced by the triggering of B7h, which is another stimulus inhibiting both ERK and p38 phosphorylation, and cell adhesiveness. Furthermore, cholbut SLN induced E-cadherin and inhibited claudin-1 expression in HUVEC. CONCLUSION AND IMPLICATIONS These results suggest that cholbut SLN could act as an anti-metastastic agent and they add a new mechanism to the anti-tumour activity of this multifaceted preparation of butyrate. PMID:22049973

Cranberry extract inhibits in vitro adhesion of F4 and F18+Escherichia coli to pig intestinal epithelium and reduces in vivo excretion of pigs orally challenged with F18+ verotoxigenic E. coli.

PubMed

Coddens, Annelies; Loos, Michaela; Vanrompay, Daisy; Remon, Jean Paul; Cox, Eric

2017-04-01

F4 + E. coli and F18 + E. coli infections are an important threat for pig industry worldwide. Antibiotics are commonly used to treat infected piglets, but the emerging development of resistance against antibiotics raises major concerns. Hence, alternative therapies to prevent pigs from F4 + E. coli and F18 + E. coli infections need to be developed. Since cranberry previously showed anti-adhesive activity against uropathogenic E. coli, we aimed to investigate whether cranberry extract could also inhibit binding of F4 + E. coli and F18 + E. coli to pig intestinal epithelium. Using the in vitro villus adhesion assay, we found that low concentrations of cranberry extract (20μg or 100μg/ml) have strong inhibitory activity on F4 + E. coli (75.3%, S.D.=9.31 or 95.8%, S.D.=2.56, respectively) and F18 + E. coli adherence (100% inhibition). This effect was not due to antimicrobial activity. Moreover, cranberry extract (10mg or 100mg) could also abolish in vivo binding of F4 and F18 fimbriae to the pig intestinal epithelium in ligated loop experiments. Finally, two challenge experiments with F18 + E. coli were performed to address the efficacy of in-feed or water supplemented cranberry extract. No effect could be observed in piglets that received cranberry extract only in feed (1g/kg or 10g/kg). However, supplementation of feed (10g/kg) and drinking water (1g/L) significantly decreased excretion and diarrhea. The decreased infection resulted in a decreased serum antibody response indicating reduced exposure to F18 + E. coli. Copyright © 2017 Elsevier B.V. All rights reserved.

Single-Port Laparoscopic Parastomal Hernia Repair with Modified Sugarbaker Technique

PubMed Central

Turingan, Isidro; Zajkowska, Marta; Tran, Kim

2014-01-01

Introduction: Laparoscopic parastomal hernia repair with modified Sugarbaker technique has become increasingly the operation of choice because of its low recurrence rates. This study aimed to assess feasibility, safety, and efficiency of performing the same operation with single-incision laparoscopic surgery. Materials and Methods: All patients referred from March 2010 to February 2013 were considered for single-port laparoscopic repair with modified Sugarbaker technique. A SILS port (Covidien, Norwalk, Connecticut, USA) was used together with conventional straight dissecting instruments and a 5.5- mm/52-cm/30° laparoscope. Important technical aspects include modified dissection techniques, namely, “inline” and “chopsticks” to overcome loss of triangulation, insertion of a urinary catheter into an ostomy for ostomy limb identification, safe adhesiolysis by avoiding electocautery, saline -jet dissection to demarcate tissue planes, dissection of an entire laparotomy scar to expose incidental incisional hernias, adequate mobilization of an ostomy limb for lateralization, and wide overlapping of defect with antiadhesive mesh. Results: Of 6 patients, 5 underwent single-port laparoscopic repair, and 1 (whose body mass index [BMI] of 39.4 kg/m2 did not permit SILS port placement) underwent multiport repair. Mean defect size was 10 cm, and mean mesh size was 660 cm2 with 4 patients having incidental incisional hernias repaired by the same mesh. Mean operation time was 270 minutes, and mean hospital stay was 4 days. Appliance malfunction ceased immediately, and pain associated with parastomal hernia disappeared. There was no recurrence with a follow-up of 2 to 36 months. Conclusion: Compared with multiport repair, single-port laparoscopic parastomal repair with modified Sugarbaker technique is safe and efficient, and it may eventually become the standard of care. PMID:24680140

Production of Lipopeptide Biosurfactant by a Marine Nesterenkonia sp. and Its Application in Food Industry

PubMed Central

Kiran, George S.; Priyadharsini, Sethu; Sajayan, Arya; Priyadharsini, Gopal B.; Poulose, Navya; Selvin, Joseph

2017-01-01

Biosurfactants are smart biomolecules which have wide spread application in medicines, processed foods, cosmetics as well as in bioremediation. In food industry, biosurfactants are used as emulsion stabilizing agents, antiadhesives, and antimicrobial/antibiofilm agents. Nowadays biosurfactant demands in industries has increased tremendously and therefore new bacterial strains are being explored for large scale production of biosurfactants. In this study, an actinobacterial strain MSA31 was isolated from a marine sponge Fasciospongia cavernosa which showed high activity in biosurfactant screening assays such as drop collapsing, oil displacement, lipase and emulsification. Lipopeptide produced by MSA31 was found to be thermostable which was evident in differential scanning calorimetry analysis. The spectral data obtained in the Fourier transform infrared spectroscopy showed the presence of aliphatic groups combined with peptide moiety which is a characteristic feature of lipopeptides. The stability index of lipopeptide MSA31 revealed “halo-alkali and thermal tolerant biosurfactant” which can be used in the food industry. Microtiter plate assay showed 125 μg/ml of lipopeptide was effective in reducing the biofilm formation activity of pathogenic multidrug resistant Staphylococcus aureus. The confocal laser scanning microscopic images provided further evidences that lipopeptide MSA31 was an effective antibiofilm agent. The antioxidant activity of lipopeptide MSA31 may be due to the presence of unsaturated fatty acid present in the molecule. The brine shrimp cytotoxicity assay showed lipopeptide MSA31 was non-toxic and can be used as food additives. Incorporation of lipopeptide MSA31 in muffin showed improved organoleptic qualities compared to positive and negative control. This study provides a valuable input for this lipopeptide to be used in food industry as an effective emulsifier, with good antioxidant activity and as a protective agent against S. aureus. PMID:28702002

[Prevention and preventive therapy of age-related macular degeneration through the beneficial effect of treatment of endothelial dysfunction].

PubMed

Fischer, Tamás

2006-12-24

The beneficial effect achieved by the treatment of endothelial dysfunction in chronic cardiovascular diseases is already an evidence belonging to the basic treatment of the disease. Given the fact that the vascular system is uniform and consubstantial both physiologically, pathophysiologically and in terms of therapy, and that it plays a key role in age-related macular degeneration (AMD) - a disease leading to tragic loss of vision with its etiology and therapy being unknown -, endothelial dysfunction should be treated. The pleiotropic effects of ACE-inhibitors, AR-blockers and statins help to restitute the balance between vasodilators and vasoconstrictors in endothelial dysfunction caused by oxidative stress, the balance of growth factors and their inhibitors, pro- and anti-inflammatory substances and prothrombotic and fibrinolytic factors, inhibit the formation of oxidative stress and its harmful effects; while aspirin with its pleiotropic effects acting as an antiaggregation substance on platelets helps to set the endothelial layer back to its normal balance regarding its vasodilating, antithrombotic, anti-adhesive and anti-inflammatory functions. For the above reasons it is suggested that, as a part of long term primary and/or secondary prevention, the following groups of patients with AMD receive - taking into consideration all possible side effects - ACE-inhibitor and/or AR-blocker and statin and aspirin treatment: 1) those without maculopathy but being over the age of 50 and having risk factors inducing endothelial dysfunction; 2) those, who already developed AMD in one eye as a prevention in the second, unaffected eye; and 3) those patients who developed AMD in both eyes in order to ameliorate or merely slow the progression of the disease. Besides, it is advisory to inhibit AMD risk factors inducing oxidative stress with consecutive endothelial dysfunction.

CD8+ T Cells Induce Fatal Brainstem Pathology during Cerebral Malaria via Luminal Antigen-Specific Engagement of Brain Vasculature

PubMed Central

Swanson, Phillip A.; Hart, Geoffrey T.; Russo, Matthew V.; Nayak, Debasis; Yazew, Takele; Peña, Mirna; Khan, Shahid M.; Pierce, Susan K.; McGavern, Dorian B.

2016-01-01

Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection that results in thousands of deaths each year, mostly in African children. The in vivo mechanisms underlying this fatal condition are not entirely understood. Using the animal model of experimental cerebral malaria (ECM), we sought mechanistic insights into the pathogenesis of CM. Fatal disease was associated with alterations in tight junction proteins, vascular breakdown in the meninges / parenchyma, edema, and ultimately neuronal cell death in the brainstem, which is consistent with cerebral herniation as a cause of death. At the peak of ECM, we revealed using intravital two-photon microscopy that myelomonocytic cells and parasite-specific CD8+ T cells associated primarily with the luminal surface of CNS blood vessels. Myelomonocytic cells participated in the removal of parasitized red blood cells (pRBCs) from cerebral blood vessels, but were not required for the disease. Interestingly, the majority of disease-inducing parasite-specific CD8+ T cells interacted with the lumen of brain vascular endothelial cells (ECs), where they were observed surveying, dividing, and arresting in a cognate peptide-MHC I dependent manner. These activities were critically dependent on IFN-γ, which was responsible for activating cerebrovascular ECs to upregulate adhesion and antigen-presenting molecules. Importantly, parasite-specific CD8+ T cell interactions with cerebral vessels were impaired in chimeric mice rendered unable to present EC antigens on MHC I, and these mice were in turn resistant to fatal brainstem pathology. Moreover, anti-adhesion molecule (LFA-1 / VLA-4) therapy prevented fatal disease by rapidly displacing luminal CD8+ T cells from cerebrovascular ECs without affecting extravascular T cells. These in vivo data demonstrate that parasite-specific CD8+ T cell-induced fatal vascular breakdown and subsequent neuronal death during ECM is associated with luminal, antigen-dependent interactions with cerebrovasculature. PMID:27907215

Utilization and safety of sodium hyaluronate-carboxymethylcellulose adhesion barrier.

PubMed

Bashir, Shazia; Ananth, Cande V; Lewin, Sharyn N; Burke, William M; Lu, Yu-Shiang; Neugut, Alfred I; Herzog, Thomas J; Hershman, Dawn L; Wright, Jason D

2013-10-01

Little is known about the use and toxicity of antiadhesion substances such as sodium hyaluronate-carboxymethylcellulose. We analyzed the patterns of use and safety of sodium hyaluronate-carboxymethylcellulose in patients undergoing colectomy and gynecologic surgery. This is a retrospective cohort study. This study covered hospitals nationwide. All patients in the Premier Perspective database who underwent colectomy or hysterectomy from 2000 to 2010 were included in the analyses. Hyaluronate-carboxymethylcellulose use was determined by billing codes. For the primary outcome, we used hierarchical mixed-effects logistic regression models to determine the factors associated with the use of hyaluronate-carboxymethylcellulose, whereas a propensity score-matched analysis was used to secondarily assess the association between hyaluronate-carboxymethylcellulose use and toxicity (abscess, bowel and wound complications, peritonitis). We identified 382,355 patients who underwent hysterectomy and 267,368 who underwent colectomy. For hysterectomy, hyaluronate-carboxymethylcellulose use was 5.0% overall, increasing from 1.1% in 2000 to 9.8% in 2010. Hyaluronate-carboxymethylcellulose was used in 8.1% of those who underwent colectomy and increased from 6.2% in 2000 to 12.4% in 2010. The year of diagnosis and procedure volume of the attending surgeon were the strongest predictors of hyaluronate-carboxymethylcellulose use. After matching and risk adjustment, hyaluronate-carboxymethylcellulose use was not associated with abscess formation (1.5% vs 1.5%) (relative risk = 0.97; 95% CI, 0.84-1.12) in those who underwent hysterectomy. A patient receiving hyaluronate-carboxymethylcellulose had a 13% increased risk of abscess (17.4% vs 15.0%) (relative risk = 1.13; 95% CI, 1.08-1.17) after colectomy. This was an observational study. Hyaluronate-carboxymethylcellulose use has increased over the past decade for colectomy and hysterectomy. Although there is no association between hyaluronate-carboxymethylcellulose use and abscess following hysterectomy, hyaluronate-carboxymethylcellulose use was associated with a small increased risk of abscess after colectomy.

Genistein prevents hyperglycemia-induced monocyte adhesion to human aortic endothelial cells through preservation of the cAMP signaling pathway and ameliorates vascular inflammation in obese diabetic mice.

PubMed

Babu, Pon Velayutham Anandh; Si, Hongwei; Fu, Zhuo; Zhen, Wei; Liu, Dongmin

2012-04-01

Hyperglycemia-induced vascular inflammation resulting in the enhanced monocyte-endothelial cell (EC) interaction is the key event in the pathogenesis of atherosclerosis in diabetes. Here, we investigated the effect of isoflavone genistein on hyperglycemia-stimulated vascular inflammation. Human aortic EC (HAEC) were pretreated with genistein before the addition of high glucose (HG; 25 mmol/L) for 48 h. Genistein at a physiological concentration (0.1 μmol/L) significantly inhibited HG-induced adhesion of monocytes to HAEC and suppressed endothelial production of monocyte chemotactic protein-1 (MCP-1) and IL-8. Inhibition of adenylate cyclase or protein kinase A (PKA) significantly attenuated the antiadhesion effect of genistein. Consistently, genistein improved HG-impaired intracellular cAMP production and PKA activity in HAEC. Six-week-old diabetic db/db mice were untreated (db/db) or treated with a diet containing 1 g genistein/kg diet (db/db+G) for 8 wk. Their nondiabetic db/+ mice were used as normal controls. Circulating concentrations of MCP-1/JE and KC were significantly greater, whereas IL-10 concentrations were lower in db/db mice than those in normal mice. Dietary supplementation of genistein did not normalize but significantly suppressed the elevated serum concentrations of MCP-1/JE from 286 ± 30 ng/L to 181 ± 35 ng/L and KC from 321 ± 21 ng/L to 232 ± 20 ng/L while increasing that of IL-10 from 35 ± 4 ng/L to 346 ± 35 ng/L in db/db+G mice. Further, genistein treatment suppressed diabetes-induced adhesion of monocytes to EC by 87% and endothelial secretion of adhesion molecules. We conclude that genistein improves diabetes-caused vascular inflammation, which may be mediated through promoting the cAMP/PKA pathway.

Lingonberry (Vaccinium vitis-idaea) and European cranberry (Vaccinium microcarpon) proanthocyanidins: isolation, identification, and bioactivities.

PubMed

Kylli, Petri; Nohynek, Liisa; Puupponen-Pimiä, Riitta; Westerlund-Wikström, Benita; Leppänen, Tiina; Welling, Jukka; Moilanen, Eeva; Heinonen, Marina

2011-04-13

European, small-fruited cranberries (Vaccinium microcarpon) and lingonberries (Vaccinium vitis-idaea) were characterized for their phenolic compounds and tested for antioxidant, antimicrobial, antiadhesive, and antiinflammatory effects. The main phenolic compounds in both lingonberries and cranberries were proanthocyanidins comprising 63-71% of the total phenolic content, but anthocyanins, hydroxycinnamic acids, hydroxybenzoic acids, and flavonols were also found. Proanthocyanidins are polymeric phenolic compounds consisting mainly of catechin, epicatechin, gallocatechin, and epigallocatechin units. In the present study, proanthocyanidins were divided into three groups: dimers and trimers, oligomers (mDP 4-10), and polymers (mDP > 10). Catechin, epicatechin, A-type dimers and trimers were found to be the terminal units of isolated proanthocyanidin fractions. Inhibitions of lipid oxidation in liposomes were over 70% and in emulsions over 85%, and in most cases the oligomeric or polymeric fraction was the most effective. Polymeric proanthocyanidin extracts of lingonberries and cranberries were strongly antimicrobial against Staphylococcus aureus, whereas they had no effect on other bacterial strains such as Salmonella enterica sv. Typhimurium, Lactobacillus rhamnosus and Escherichia coli. Polymeric fraction of cranberries and oligomeric fractions of both lingonberries and cranberries showed an inhibitory effect on hemagglutination of E. coli, which expresses the M hemagglutin. Cranberry phenolic extract inhibited LPS-induced NO production in a dose-dependent manner, but it had no major effect on iNOS of COX-2 expression. At a concentration of 100 μg/mL cranberry phenolic extract inhibited LPS-induced IL-6, IL-1β and TNF-α production. Lingonberry phenolics had no significant effect on IL-1β production but inhibited IL-6 and TNF-α production at a concentration of 100 μg/mL similarly to cranberry phenolic extract. In conclusion the phenolics, notably proanthocyanidins (oligomers and polymers), in both lingonberries and cranberries exert multiple bioactivities that may be exploited in food development.

Melphalan, prednisone, thalidomide and defibrotide in relapsed/refractory multiple myeloma: results of a multicenter phase I/II trial.

PubMed

Palumbo, Antonio; Larocca, Alessandra; Genuardi, Mariella; Kotwica, Katarzyna; Gay, Francesca; Rossi, Davide; Benevolo, Giulia; Magarotto, Valeria; Cavallo, Federica; Bringhen, Sara; Rus, Cecilia; Masini, Luciano; Iacobelli, Massimo; Gaidano, Gianluca; Mitsiades, Constantine; Anderson, Kenneth; Boccadoro, Mario; Richardson, Paul

2010-07-01

Defibrotide is a novel orally bioavailable polydisperse oligonucleotide with anti-thrombotic and anti-adhesive effects. In SCID/NOD mice, defibrotide showed activity in human myeloma xenografts. This phase I/II study was conducted to identify the most appropriate dose of defibrotide in combination with melphalan, prednisone and thalidomide in patients with relapsed and relapsed/refractory multiple myeloma, and to determine its safety and tolerability as part of this regimen. This was a phase I/II, multicenter, dose-escalating, non-comparative, open label study. Oral melphalan was administered at a dose of 0.25 mg/kg on days 1-4, prednisone at a dose of 1.5 mg/kg also on days 1-4 and thalidomide at a dose of 50-100 mg/day continuously. Defibrotide was administered orally at three dose-levels: 2.4, 4.8 or 7.2 g on days 1-4 and 1.6, 3.2, or 4.8 g on days 5-35. Twenty-four patients with relapsed/refractory multiple myeloma were enrolled. No dose-limiting toxicity was observed. In all patients, the complete response plus very good partial response rate was 9%, and the partial response rate was 43%. The 1-year progression-free survival and 1-year overall survival rates were 34% and 90%, respectively. The most frequent grade 3-4 adverse events included neutropenia, thrombocytopenia, anemia and fatigue. Deep vein thrombosis was reported in only one patient. This combination of melphalan, prednisone and thalidomide together with defibrotide showed anti-tumor activity with a favorable tolerability. The maximum tolerated dose of defibrotide was identified as 7.2 g p.o. on days 1-4 followed by 4.8 g p.o. on days 5-35. Further trials are needed to confirm the role of this regimen and to evaluate the combination of defibrotide with new drugs.

Melphalan, prednisone, thalidomide and defibrotide in relapsed/refractory multiple myeloma: results of a multicenter phase I/II trial

PubMed Central

Palumbo, Antonio; Larocca, Alessandra; Genuardi, Mariella; Kotwica, Katarzyna; Gay, Francesca; Rossi, Davide; Benevolo, Giulia; Magarotto, Valeria; Cavallo, Federica; Bringhen, Sara; Rus, Cecilia; Masini, Luciano; Iacobelli, Massimo; Gaidano, Gianluca; Mitsiades, Constantine; Anderson, Kenneth; Boccadoro, Mario; Richardson, Paul

2010-01-01

Background Defibrotide is a novel orally bioavailable polydisperse oligonucleotide with anti-thrombotic and anti-adhesive effects. In SCID/NOD mice, defibrotide showed activity in human myeloma xenografts. This phase I/II study was conducted to identify the most appropriate dose of defibrotide in combination with melphalan, prednisone and thalidomide in patients with relapsed and relapsed/refractory multiple myeloma, and to determine its safety and tolerability as part of this regimen. Design and Methods This was a phase I/II, multicenter, dose-escalating, non-comparative, open label study. Oral melphalan was administered at a dose of 0.25 mg/kg on days 1–4, prednisone at a dose of 1.5 mg/kg also on days 1–4 and thalidomide at a dose of 50–100 mg/day continuously. Defibrotide was administered orally at three dose-levels: 2.4, 4.8 or 7.2 g on days 1–4 and 1.6, 3.2, or 4.8 g on days 5–35. Results Twenty-four patients with relapsed/refractory multiple myeloma were enrolled. No dose-limiting toxicity was observed. In all patients, the complete response plus very good partial response rate was 9%, and the partial response rate was 43%. The 1-year progression-free survival and 1-year overall survival rates were 34% and 90%, respectively. The most frequent grade 3–4 adverse events included neutropenia, thrombocytopenia, anemia and fatigue. Deep vein thrombosis was reported in only one patient. Conclusions This combination of melphalan, prednisone and thalidomide together with defibrotide showed anti-tumor activity with a favorable tolerability. The maximum tolerated dose of defibrotide was identified as 7.2 g p.o. on days 1–4 followed by 4.8 g p.o. on days 5–35. Further trials are needed to confirm the role of this regimen and to evaluate the combination of defibrotide with new drugs (ClinicalTrials.gov Identifier: NCT00406978). PMID:20053869

Antecedent hydrogen sulfide elicits an anti-inflammatory phenotype in postischemic murine small intestine: role of BK channels

PubMed Central

Zuidema, Mozow Y.; Yang, Yan; Wang, Meifang; Kalogeris, Theodore; Liu, Yajun; Meininger, Cynthia J.; Hill, Michael A.; Davis, Michael J.

2010-01-01

The objectives of this study were to determine the role of calcium-activated, small (SK), intermediate (IK), and large (BK) conductance potassium channels in initiating the development of an anti-inflammatory phenotype elicited by preconditioning with an exogenous hydrogen sulfide (H2S) donor, sodium hydrosulfide (NaHS). Intravital microscopy was used to visualize rolling and firmly adherent leukocytes in vessels of the small intestine of mice preconditioned with NaHS (in the absence and presence of SK, IK, and BK channel inhibitors, apamin, TRAM-34, and paxilline, respectively) or SK/IK (NS-309) or BK channel activators (NS-1619) 24 h before ischemia-reperfusion (I/R). I/R induced marked increases in leukocyte rolling and adhesion, effects that were largely abolished by preconditioning with NaHS, NS-309, or NS-1619. The postischemic anti-inflammatory effects of NaHS-induced preconditioning were mitigated by BKB channel inhibitor treatment coincident with NaHS, but not by apamin or TRAM-34, 24 h before I/R. Confocal imaging and immunohistochemistry were used to demonstrate the presence of BKα subunit staining in both endothelial and vascular smooth muscle cells of isolated, pressurized mesenteric venules. Using patch-clamp techniques, we found that BK channels in cultured endothelial cells were activated after exposure to NaHS. Bath application of the same concentration of NaHS used in preconditioning protocols led to a rapid increase in a whole cell K+ current; specifically, the component of K+ current blocked by the selective BK channel antagonist iberiotoxin. The activation of BK current by NaHS could also be demonstrated in single channel recording mode where it was independent of a change in intracellular Ca+ concentration. Our data are consistent with the concept that H2S induces the development of an anti-adhesive state in I/R in part mediated by a BK channel-dependent mechanism. PMID:20833953

Post-operative adhesions after digestive surgery: their incidence and prevention: review of the literature.

PubMed

Ouaïssi, M; Gaujoux, S; Veyrie, N; Denève, E; Brigand, C; Castel, B; Duron, J J; Rault, A; Slim, K; Nocca, D

2012-04-01

Post-operative adhesions after gastrointestinal surgery are responsible for significant morbidity and constitute an important public health problem. The aim of this study was to review the surgical literature to determine the incidence, consequences and the variety of possible countermeasures to prevent adhesion formation. A systematic review of English and French language surgical literature published between 1995 and 2009 was performed using the keywords "adhesion" and "surgery". Peritoneal adhesions are reported as the cause of 32% of acute intestinal obstruction and 65-75% of all small bowel obstructions. It is estimated that peritoneal adhesions develop after 93-100% of upper abdominal laparotomies and after 67-93% of lower abdominal laparotomies. Nevertheless, only 15-18% of these adhesions require surgical re-intervention. The need for re-intervention for adhesion-related complications varies depending on the initial type of surgery, the postoperative course and the type of incision. The laparoscopic approach appears to decrease the risk of adhesion formation by 45% and the need for adhesion-related re-intervention to 0.8% after appendectomy and to 2.5% after colorectal surgery. At the present time, only one product consisting of hyaluronic acid applied to a layer of carboxymethylcellulose (Seprafilm(®)) has been shown to significantly reduce the incidence of postoperative adhesion formation; but this product is also associated with a significant increase in the incidence of anastomotic leakage when the membrane is applied in direct contact with the anastomosis. The use of this product has not been shown to decrease the risk of re-intervention for bowel obstruction. The prevention of postoperative adhesions is an important public health goal, particularly in light of the frequency of this complication. The routine use of anti-adhesion products is not recommended given the lack of studies with a high level of evidence concerning their efficacy and safety of use. Copyright © 2012. Published by Elsevier Masson SAS.

CAD-based strength analysis of EK-18 excavator bucket construction for mounting of anti-adhesive devices

NASA Astrophysics Data System (ADS)

Zenkov, S. A.; Lobanov, D. V.

2018-03-01

3D rigid-body model of a bucket of power shovel EK-18 was built using modern CAD-software. Tetrahedral grid with 10-node second-order elements was chosen, and the given model was imported to APM WinMachine - model preparation preprocessor for finite element analysis. The finite element model was based on the geometrical model, imported from KOMPAS-3D to APM Studio. Calculation of stressed-strained state of the bucket was carried out under the forces emerging while digging with “back hoe” equipment. Shift, deformation and tension charts were planned and the most and the least strained areas were pointed out. Wet coherent soil excavation deals with soil adhesion to working bodies of power shovels and leads to reduced performance. The performance decrease is caused by a reduction of useful bucket capacity and partial unloading, increased front resistance to cutting (digging) caused by wet soil adhesion to a working body, increased bucket entry resistance, increased idle time caused by necessity to clean working bodies. Also energy losses increase and quality of work drops because friction forces go up. Friction force occurs while digging and levelling account for 30…70 percent of total digging resistance while performance decreases 1.2…2 times and more. Vibrothermal exposure creates new technological effect which involves a wider humidity range of efficient application and a reduction of friction forces. Disintegrating adhesion bonds with heating requires less driving force from the vibrator. Vibration boosts up heating of the contact layer, which reduces thermal energy losses. However, the question of piezoelectric ceramic actuators location on the excavator bucket needs to be dealt with. The most suitable spots for mounting piezoelectric ceramic devices for reducing soil adhesion to the excavator bucket were defined. Their efficiency is derived from combined (vibrothermal) methods of exposure. Such devices eliminates soil adhesion to the bucket and increases efficiency of using power shovels with wet coherent soils.

Mesh fixation in laparoscopic incisional hernia repair: glue fixation provides attachment strength similar to absorbable tacks but differs substantially in different meshes.

PubMed

Rieder, Erwin; Stoiber, Martin; Scheikl, Verena; Poglitsch, Marcus; Dal Borgo, Andrea; Prager, Gerhard; Schima, Heinrich

2011-01-01

Laparoscopic ventral hernia repair has gained popularity among minimally invasive surgeons. However, mesh fixation remains a matter of discussion. This study was designed to compare noninvasive fibrin-glue attachment with tack fixation of meshes developed primarily for intra-abdominal use. It was hypothesized that particular mesh structures would substantially influence detachment force. For initial evaluation, specimens of laminated polypropylene/polydioxanone meshes were anchored to porcine abdominal walls by either helical titanium tacks or absorbable tacks in vitro. A universal tensile-testing machine was used to measure tangential detachment forces (TF). For subsequent experiments of glue fixation, polypropylene/polydioxanone mesh and 4 additional meshes with diverse particular mesh structure, ie, polyvinylidene fluoride/polypropylene mesh, a titanium-coated polypropylene mesh, a polyester mesh bonded with a resorbable collagen, and a macroporous condensed PTFE mesh were evaluated. TF tests revealed that fibrin-glue attachment was not substantially different from that achieved with absorbable tacks (median TF 7.8 Newton [N], range 1.3 to 15.8 N), but only when certain open porous meshes (polyvinylidene fluoride/polypropylene mesh: median 6.2 N, range 3.4 to 10.3 N; titanium-coated polypropylene mesh: median 5.2 N, range 2.1 to 11.7 N) were used. Meshes coated by an anti-adhesive barrier (polypropylene/polydioxanone mesh: median 3.1 N, range 1.7 to 5.8 N; polyester mesh bonded with a resorbable collagen: median 1.3 N, range 0.5 to 1.9 N), or the condensed PTFE mesh (median 3.1 N, range 2.1 to 7.0 N) provided a significantly lower TF (p < 0.01). Fibrin glue appears to be an appealing noninvasive option for mesh fixation in laparoscopic ventral hernia repair, but only if appropriate meshes are used. Glue can also serve as an adjunct to mechanical fixation to reduce the number of invasive tacks. Copyright © 2010 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Spheroid Culture of Head and Neck Cancer Cells Reveals an Important Role of EGFR Signalling in Anchorage Independent Survival.

PubMed

Braunholz, Diana; Saki, Mohammad; Niehr, Franziska; Öztürk, Merve; Borràs Puértolas, Berta; Konschak, Robert; Budach, Volker; Tinhofer, Ingeborg

2016-01-01

In solid tumours millions of cells are shed into the blood circulation each day. Only a subset of these circulating tumour cells (CTCs) survive, many of them presumable because of their potential to form multi-cellular clusters also named spheroids. Tumour cells within these spheroids are protected from anoikis, which allows them to metastasize to distant organs or re-seed at the primary site. We used spheroid cultures of head and neck squamous cell carcinoma (HNSCC) cell lines as a model for such CTC clusters for determining the role of the epidermal growth factor receptor (EGFR) in cluster formation ability and cell survival after detachment from the extra-cellular matrix. The HNSCC cell lines FaDu, SCC-9 and UT-SCC-9 (UT-SCC-9P) as well as its cetuximab (CTX)-resistant sub-clone (UT-SCC-9R) were forced to grow in an anchorage-independent manner by coating culture dishes with the anti-adhesive polymer poly-2-hydroxyethylmethacrylate (poly-HEMA). The extent of apoptosis, clonogenic survival and EGFR signalling under such culture conditions was evaluated. The potential of spheroid formation in suspension culture was found to be positively correlated with the proliferation rate of HNSCC cell lines as well as their basal EGFR expression levels. CTX and gefitinib blocked, whereas the addition of EGFR ligands promoted anchorage-independent cell survival and spheroid formation. Increased spheroid formation and growth were associated with persistent activation of EGFR and its downstream signalling component (MAPK/ERK). Importantly, HNSCC cells derived from spheroid cultures retained their clonogenic potential in the absence of cell-matrix contact. Addition of CTX under these conditions strongly inhibited colony formation in CTX-sensitive cell lines but not their resistant subclones. Altogether, EGFR activation was identified as crucial factor for anchorage-independent survival of HNSCC cells. Targeting EGFR in CTC cluster formation might represent an attractive anti-metastatic treatment approach in HNSCC.

Acute Effects of Nitrate-Rich Beetroot Juice on Blood Pressure, Hemostasis and Vascular Inflammation Markers in Healthy Older Adults: A Randomized, Placebo-Controlled Crossover Study

PubMed Central

Raubenheimer, Kyle; Hickey, Danica; Leveritt, Michael; Fassett, Robert; Ortiz de Zevallos Munoz, Joaquin; Briskey, David; Kerr, Graham; Peake, Jonathan M.; Pecheniuk, Natalie M.

2017-01-01

Aging is associated with a vasoconstrictive, pro-coagulant, and pro-inflammatory profile of arteries and a decline in the bioavailability of the endothelium-derived molecule nitric oxide. Dietary nitrate elicits vasodilatory, anti-coagulant and anti-inflammatory effects in younger individuals, but little is known about whether these benefits are evident in older adults. We investigated the effects of 140 mL of nitrate-rich (HI-NI; containing 12.9 mmol nitrate) versus nitrate-depleted beetroot juice (LO-NI; containing ≤0.04 mmol nitrate) on blood pressure, blood coagulation, vascular inflammation markers, plasma nitrate and nitrite before, and 3 h and 6 h after ingestion in healthy older adults (five males, seven females, mean age: 64 years, age range: 57–71 years) in a randomized, placebo-controlled, crossover study. Plasma nitrate and nitrite increased 3 and 6 h after HI-NI ingestion (p < 0.05). Systolic, diastolic and mean arterial blood pressure decreased 3 h relative to baseline after HI-NI ingestion only (p < 0.05). The number of blood monocyte-platelet aggregates decreased 3 h after HI-NI intake (p < 0.05), indicating reduced platelet activation. The number of blood CD11b-expressing granulocytes decreased 3 h following HI-NI beetroot juice intake (p < 0.05), suggesting a shift toward an anti-adhesive granulocyte phenotype. Numbers of blood CD14++CD16+ intermediate monocyte subtypes slightly increased 6 h after HI-NI beetroot juice ingestion (p < 0.05), but the clinical implications of this response are currently unclear. These findings provide new evidence for the acute effects of nitrate-rich beetroot juice on circulating immune cells and platelets. Further long-term research is warranted to determine if these effects reduce the risk of developing hypertension and vascular inflammation with aging. PMID:29165355

Blockade of αEβ7 integrin suppresses accumulation of CD8+ and Th9 lymphocytes from patients with IBD in the inflamed gut in vivo.

PubMed

Zundler, Sebastian; Schillinger, Daniela; Fischer, Anika; Atreya, Raja; López-Posadas, Rocío; Watson, Alastair; Neufert, Clemens; Atreya, Imke; Neurath, Markus F

2017-11-01

Therapeutically targeting lymphocyte adhesion is of increasing relevance in IBD. Yet, central aspects of the action of antiadhesion compounds are incompletely understood. We investigated the role of αEβ7 and α4β7 integrins and their blockade by vedolizumab and etrolizumab for trafficking of IBD T lymphocytes in an in vivo model of homing to and retention in the inflamed gut. We explored integrin expression in patients with IBD by flow cytometry and immunohistochemistry, while regulation of integrins was studied in T cell cultures. The functional relevance of integrins was assessed by adhesion assays and a recently established humanised mouse model in dextran sodium sulfate-treated immunodeficient mice. High expression of αEβ7 was noted on CD8 + and CD4 + Th9 cells, while α4β7 was expressed on CD8 + , Th2 and Th17 cells. T cell receptor stimulation and transforming growth factor β were key inducers of αEβ7 on human T cells, while butyric acid suppressed αEβ7. In comparison to α4β7 blockade via vedolizumab, blockade of β7 via etrolizumab surrogate antibody superiorly reduced colonic numbers of CD8 + and Th9 cells in vivo after 3 hours, while no difference was noted after 0.5 hours. AEβ7 expression was higher on CD8 + T cells from patients with IBD under vedolizumab therapy. AEβ7 is of key relevance for gut trafficking of IBD CD8 + T cells and CD4 + Th9 cells in vivo and mainly retention might account for this effect. These findings indicate that blockade of αEβ7 in addition to α4β7 may be particularly effective in intestinal disorders with expansion of CD8 + and Th9 cells such as IBD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Optimizing the production of the biosurfactant lichenysin and its application in biofilm control.

PubMed

Coronel-León, J; Marqués, A M; Bastida, J; Manresa, A

2016-01-01

Apply response surface methodology (RSM) to develop and optimize an economical medium for lichenysin production, which is a surfactant produced by Bacillus licheniformis and evaluate the application of lichenysin in the prevention and disruption of pathogenic micro-organism biofilm that creates health problems in the food industry and hospitals. An economical medium containing molasses was optimized to enhance lichenysin production by RSM. A production of 3·2 g l(-1) of lichenysin was achieved with an optimum medium containing 107·82 g l(-1) of molasses, 6·47 g l(-1) of NaNO3 and 9·7 g l(-1) of K2 HPO4 /KH2 PO4 , in which molasses and phosphate salts had a significant effect on biosurfactant production. Lichenysin was effectively applied in a surface pre-treatment to avoid microbial biofilm development of methicillin-resistant Staphylococcus aureus (MRSA) (68·73%) and Candida albicans (74·35%), with ED50 values of 8·3 and 17·2 μg ml(-1) respectively. It was also very efficient in a surface post-treatment to remove biofilms of MRSA (55·74%) and Yersinia enterocolitica (51·51%), with an ED50 of 2·79 and 4·09 μg ml(-1) respectively. Lichenysin was found to have notable anti-adhesion activity, being able to prevent and eliminate the biofilm formation by pathogenic strains associated with foodborne illness. This new medium resulted in a four-fold increase in production compared with the nonoptimized medium. Molasses can be regarded as a useful resource for biotechnological applications, such as the production of lichenysin. The use of agro-industrial substrates has an important role in the sustainable and competitive development of several industrial sectors, as well as in industrial residues management. Additionally, lichenysin is particularly effective in preventing biofilm formation by strains problematic for the food industry and in the hospital environment. Lichenysin also efficiently disrupts biofilm. © 2015 The Society for Applied Microbiology.

Pharmacological effects and potential therapeutic targets of DT-13.

PubMed

Khan, Ghulam Jilany; Rizwan, Mohsin; Abbas, Muhammad; Naveed, Muhammad; Boyang, Yu; Naeem, Muhammad Ahsan; Khan, Sara; Yuan, Shengtao; Baig, Mirza Muhammad Faran Ashraf; Sun, Li

2018-01-01

DT-13 is an isolated compound from Dwarf lillytruf tuber and currently among active research drugs by National Natural Science foundation of China for its several potential effects. The drug has been reported for its multiple pharmacological actions however no thorough review studies are available on it. Our present study is highlighting the pros and cons of DT-13 focusing on its potential pharmacological actions, therapeutic utilization and further exploration for novel targets. The drug possesses very low toxicity profile, quick onset and long duration of action with slow elimination that combinely makes it favorable for the clinical studies. In vivo and in vitro studies show that the drug regulates multiple cellular functions for its several pharmacological effects including, anti-adhesive effects via regulation of tissue factor and transforming growth factor; anti-migratory effects through indirect regulation of NM-IIA in the tumor microenvironment, Tissue factor, down-regulation of CCR5-CCL5 axis and MMP-2/9 inhibition; anti-metastatic effects via regulation of MMPs and tissue factor; pro-apoptotic effects by modulation of endocytosis of EGF receptor; anti-angiogenic effects via regulation of HIF-1α,ERK, Akt signalling and autophagy inducing characteristics by regulating PI3K/Akt/mTOR signalling pathway. In addition to anti-tumor activities, DT-13 has significant anti-inflammatory, cardioprotective, hepatoprotective and immunomodulating effects. Pharmaceutical dosage form and targeted drug delivery system for DT-13 has not been established yet. Moreover, DT-13, has not been studied for its action on brain, colorectal, hepatic, pancreatic, prostate and blood cancers. Similarly the effects of drug on carbohydrate and glucose metabolism is another niche yet to be explored. In some traditional therapies, crude drug from the plant is used against diabetic and neurological disorders that are not reported in scientific literature, however due to profound effects of DT-13 on blood and cerebral ischemic disorders, it is reasonable to hypothesize that there could be an association of DT-13 that require further exploration. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Proteins other than the locus of enterocyte effacement-encoded proteins contribute to Escherichia coli O157:H7 adherence to bovine rectoanal junction stratified squamous epithelial cells

PubMed Central

2012-01-01

Background In this study, we present evidence that proteins encoded by the Locus of Enterocyte Effacement (LEE), considered critical for Escherichia coli O157 (O157) adherence to follicle-associated epithelial (FAE) cells at the bovine recto-anal junction (RAJ), do not appear to contribute to O157 adherence to squamous epithelial (RSE) cells also constituting this primary site of O157 colonization in cattle. Results Antisera targeting intimin-γ, the primary O157 adhesin, and other essential LEE proteins failed to block O157 adherence to RSE cells, when this pathogen was grown in DMEM, a culture medium that enhances expression of LEE proteins. In addition, RSE adherence of a DMEM-grown-O157 mutant lacking the intimin protein was comparable to that seen with its wild-type parent O157 strain grown in the same media. These adherence patterns were in complete contrast to that observed with HEp-2 cells (the adherence to which is mediated by intimin-γ), assayed under same conditions. This suggested that proteins other than intimin-γ that contribute to adherence to RSE cells are expressed by this pathogen during growth in DMEM. To identify such proteins, we defined the proteome of DMEM-grown-O157 (DMEM-proteome). GeLC-MS/MS revealed that the O157 DMEM-proteome comprised 684 proteins including several components of the cattle and human O157 immunome, orthologs of adhesins, hypothetical secreted and outer membrane proteins, in addition to the known virulence and LEE proteins. Bioinformatics-based analysis of the components of the O157 DMEM proteome revealed several new O157-specific proteins with adhesin potential. Conclusion Proteins other than LEE and intimin-γ proteins are involved in O157 adherence to RSE cells at the bovine RAJ. Such proteins, with adhesin potential, are expressed by this human pathogen during growth in DMEM. Ongoing experiments to evaluate their role in RSE adherence should provide both valuable insights into the O157-RSE interactions and new targets for more efficacious anti-adhesion O157 vaccines. PMID:22691138

Towards a Scalable, Biomimetic, Antibacterial Coating

NASA Astrophysics Data System (ADS)

Dickson, Mary Nora

Corneal afflictions are the second leading cause of blindness worldwide. When a corneal transplant is unavailable or contraindicated, an artificial cornea device is the only chance to save sight. Bacterial or fungal biofilm build up on artificial cornea devices can lead to serious complications including the need for systemic antibiotic treatment and even explantation. As a result, much emphasis has been placed on anti-adhesion chemical coatings and antibiotic leeching coatings. These methods are not long-lasting, and microorganisms can eventually circumvent these measures. Thus, I have developed a surface topographical antimicrobial coating. Various surface structures including rough surfaces, superhydrophobic surfaces, and the natural surfaces of insects' wings and sharks' skin are promising anti-biofilm candidates, however none meet the criteria necessary for implementation on the surface of an artificial cornea device. In this thesis I: 1) developed scalable fabrication protocols for a library of biomimetic nanostructure polymer surfaces 2) assessed the potential these for poly(methyl methacrylate) nanopillars to kill or prevent formation of biofilm by E. coli bacteria and species of Pseudomonas and Staphylococcus bacteria and improved upon a proposed mechanism for the rupture of Gram-negative bacterial cell walls 3) developed a scalable, commercially viable method for producing antibacterial nanopillars on a curved, PMMA artificial cornea device and 4) developed scalable fabrication protocols for implantation of antibacterial nanopatterned surfaces on the surfaces of thermoplastic polyurethane materials, commonly used in catheter tubings. This project constitutes a first step towards fabrication of the first entirely PMMA artificial cornea device. The major finding of this work is that by precisely controlling the topography of a polymer surface at the nano-scale, we can kill adherent bacteria and prevent biofilm formation of certain pathogenic bacteria, without the use of any chemical antibiotic agents. Such nanotopographic coatings can be applied to implantable polymer medical devices with scalable, commercializable processes, and may deter or delay biofilm formation, potentially improving patient outcomes. This thesis also opens the door for adaptation of antibacterial, nanopillared surfaces for other applications including other medical devices, marine applications and environmental surfaces.

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.

PubMed

Stommel, Martijn W J; Strik, Chema; ten Broek, Richard P G; van Goor, Harry

2014-09-26

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. 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). 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. ClinicalTrials.gov Identifier NCT01872650, registration date 6 June 2013.

New treatment options for inflammatory bowel diseases.

PubMed

Verstockt, Bram; Ferrante, Marc; Vermeire, Séverine; Van Assche, Gert

2018-05-01

The advent of anti-TNF agents has dramatically changed the treatment algorithms for IBD in the last 15 years, but primarily and more importantly secondary loss of response is often observed. Fortunately , new treatment options have been actively explored and some have already entered our clinical practice. In the class of anti-cytokine agents, the anti-IL12/IL23 monoclonal antibodies (mAbs) have entered clinical practice with the anti-p40 mAb ustekinumab in Crohn's disease (CD). Also, more selective anti-IL23 agents (anti-p19) have shown efficacy and are being further developed, in contrast to agents inhibiting IL-17 downstream which have failed in clinical trials despite their clear efficacy in psoriasis (Verstockt et al. in Expert Opin Biol Ther 17(1):31-47, 2017; Verstockt et al. in Expert Opin Drug Saf 16(7):809-821, 2017). Following up on the efficacy of the anti-adhesion molecule vedolizumab, etrolizumab (anti-beta-7 integrin) and PF-00547659, an anti-MadCam mAb, are being developed (Lobaton et al. in Aliment Pharmacol Ther 39(6):579-594, 2014). Oral anti-trafficking agents, such as ozanimod, targeting the S1P receptor responsible for the efflux of T-cells from the lymph nodes, have also shown efficacy in patients with ulcerative colitis (UC) (Sandborn et al. in N Engl J Med 374(18):1754-1762, 2016). Oral agents inhibiting cell signaling have been explored successfully in IBD. Tofacitinib, a non-selective oral Janus kinase (JAK) inhibitor, is effective in patients with UC and several other more or less selective Jak1, 2 and 3 inhibitors are being developed for the treatment of CD and UC (Sandborn et al. in N Engl J Med 376(18):1723-1736, 2017; Vermeire et al. in Lancet 389(10066):266-275, 2017; De Vries et al. in J Crohns Colitis 11(7):885-93, 2017). Finally, despite initial disappointing results with systemic administration of mesenchymal stem cells, Alofisel, adipose tissue derived, allogeneic mesenchymal stem cells, locally injected in perianal fistula tracts, induce long-lasting beneficial effects and the drug has been approved in Europe (Panes et al. in Gastroenterology, 2017). In summary, the quest for new treatment options in IBD is very active and justified by the high medical need and unresolved problems patients are facing.

[A new possible strategy for prevention and preventive treatment of age-related macular degeneration resting on recent clinical and pathophysiological observations].

PubMed

Fischer, Tamás

2009-03-15

The beneficial effect achieved by the treatment of endothelial dysfunction in chronic cardiovascular diseases is already an evidence belonging to the basic treatment of the disease. Given the fact that the vascular system is uniform and consubstantial both physiologically, pathophysiologically and in terms of therapy, and that it plays a key role in age-related macular degeneration (AMD)--a disease leading to tragic loss of vision with its etiology and therapy being unknown--endothelial dysfunction should be treated. The pleiotropic effects of ACE-inhibitors, AR-blockers and statins and third generation beta blockers help to restitute the balance between vasodilators and vasoconstrictors in endothelial dysfunction caused by oxidative stress, the balance of growth factors and their inhibitors, pro- and anti-inflammatory substances and prothrombotic and fibrinolytic factors, inhibit the formation of oxidative stress and its harmful effects; while aspirin with its pleiotropic effects acting as an antiaggregation substance on platelets helps to set the endothelial layer back to its normal balance regarding its vasodilating, antithrombotic, antiadhesive and anti-inflammatory functions; trimetazidine as an adjuvant agent helps to normalize, to restore the disturbed metabolism of the retinal tissue functioning insufficiently, in the end. The angiotensin II receptor blocker telmisartan with its peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonist effect inhibits the development of choroidal neovascularisation (CNV) and improves it clinically favourably. The third generation beta adrenergic receptor blocker carvedilol and nebivolol as well as the peroxisome proliferator-activated receptor-gamma agonist pioglitazone elicit their antioxidant vascular protective effects mitochondrially. For the above reasons it is suggested that, as a part of long term primary and/or secondary prevention, the following groups of patients with AMD receive--taking into consideration all possible side effects--ACE-inhibitor and/or AR blocker and statin and aspirin treatment, and trimetazidine as adjuvant medicine, and third generation beta adrenergic receptor blockers: 1. those without macular degeneration but being above the age of 50 and having risk factors inducing endothelial dysfunction; 2. those, who already developed AMD in one eye as a prevention in the second, unaffected eye; and 3. those patients who developed AMD in both eyes in order to ameliorate or merely slow the progression of the disease. Besides, it is advisory and important to eliminate AMD risk factors (cardiovascular risk factors also) inducing oxidative stress with consecutive endothelial dysfunction.

Development and Demonstration of a Multiplexed Magnetic Tweezers Assay

NASA Astrophysics Data System (ADS)

Johnson, Keith Charles

This dissertation is concerned with the methods and applications of single molecule force spectroscopy. In the introduction, the traditional single molecule force spectroscopy instruments are introduced and the advantages and drawbacks of each are discussed. The first chapter is a review of methods to ensure that biomolecular bond lifetime parameter estimations are not contaminated by multiple bond data. This review culminates in an examination of the literature on the strength of the bond between biotin and streptavidin and finds that by filtering the numerous publications for those that clearly demonstrate specific single bond behavior, there is a consensus of the bond strength and kinetic parameters. The second chapter of the dissertation discusses the capabilities of a magnetic tweezer assay, which combines massive multiplexing, precision bead tracking, and bi-directional force control into a flexible and stabile platform for examining single molecule behavior. Using a novel method for increasing the precision of force estimations on heterogeneous paramagnetic beads, I demonstrate the instrument by examining the force dependence of uncoiling and recoiling velocity of type 1 fimbriae from Eschericia coli (E. coli) bacteria, and see similar results to previous studies. Chapter 3 is a study of the lifetime of the activated FimH-mannose bond under various force conditions using the previously described magnetic tweezer. The bond is found to be extremely long-lived at forces less than 30 pN, with an average lifetime > 1000 times longer than the biotin-streptavidin bond, making it one of the strongest non-covalent interactions known in nature. Furthermore, the average lifetime of the bond is similar between 9 and 30 pN of force, suggesting a force range at which the lifetime is force-independent, demonstrating ideal bond behavior for the first time in a natural system. It is hypothesized that the long lifetime and ideal behavior is due to a gateway that locks mannose into the binding pocket and opens at a rate independent of force. This study elucidates a mechanism for very strong biological binding, and provides insight into approaches for developing novel antiadhesive therapies. This dissertation is concluded with a review of the body of work in chapters 1-3 and a discussion of the future directions for this research.

Prophylactic antibiotics for preventing Gram positive infections associated with long-term central venous catheters in oncology patients.

PubMed

van de Wetering, Marianne D; van Woensel, Job B M; Lawrie, Theresa A

2013-11-25

This is an updated version of the review which was first published in the Cochrane Database of Systematic Reviews in 2006. Long-term central venous catheters (CVCs), including tunnelled CVCs (TCVCs) and totally implanted devices or ports (TIDs), are increasingly used when treating oncology patients. Despite international guidelines on sterile insertion and appropriate CVC maintenance and use, infection remains a common complication. These infections are mainly caused by Gram positive bacteria. Antimicrobial prevention strategies aimed at these micro-organisms could potentially decrease the majority of CVC infections. The aim of this review was to evaluate the efficacy of antibiotics in the prevention of Gram positive infections in long-term CVCs. To determine the efficacy of administering antibiotics prior to the insertion of long-term CVCs, or flushing or locking long-term CVCs with a combined antibiotic and heparin solution, or both, to prevent Gram positive catheter-related infections in adults and children receiving treatment for cancer. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (to June 2013) and the MEDLINE and EMBASE databases (1966 to 2013). Randomised controlled trials (RCTs) comparing prophylactic antibiotics given prior to long-term CVC insertion with no antibiotics, RCTs comparing a combined antibiotic and heparin solution with a heparin-only solution to flush or lock newly inserted long-term CVCs, and RCTs comparing a combination of these interventions in adults and children receiving treatment for cancer. Two authors independently selected studies, classified them and extracted data on to a pre-designed data collection form. We pooled data using the RevMan software version 5.2 and used random-effects (RE) model methods for meta-analyses. We included 11 trials with a total of 828 oncology patients (adults and children). We assessed most included studies to be at a low or unclear risk of bias. Five trials compared the use of antibiotics (vancomycin, teicoplanin or ceftazidime) given before the insertion of the long-term CVC with no antibiotics, and six trials compared antibiotics (vancomycin, amikacin or taurolidine) and heparin with a heparin-only solution for flushing or locking the long-term CVC after use. Administering an antibiotic prior to insertion of the CVC did not significantly reduce Gram positive catheter-related sepsis (CRS) (five trials, 360 adults; risk ratio (RR) 0.72, 95% confidence interval (CI) 0.33 to 1.58; I² = 5 2%; P = 0.41).Flushing and locking long-term CVCs with a combined antibiotic and heparin solution significantly reduced the risk of Gram positive catheter-related sepsis compared with a heparin-only solution (468 participants, mostly children; RR 0.47, 95% CI 0.28 to 0.80; I² = 0%; P = 0.005). For a baseline infection rate of 15%, this reduction translated into a number needed to treat (NNT) of 12 (95% CI 9 to 33) to prevent one catheter-related infection. We considered this evidence to be of a moderate quality. There was no benefit to administering antibiotics before the insertion of long-term CVCs to prevent Gram positive catheter-related infections. Flushing or locking long-term CVCs with a combined antibiotic and heparin solution appeared to reduce Gram positive catheter-related sepsis experienced in people at risk of neutropenia through chemotherapy or disease. Due to insufficient data it was not clear whether this applied equally to TCVCs and totally implanted devices (TIDs), or equally to adults and children. The use of a combined antibiotic and heparin solution may increase microbial antibiotic resistance, therefore it should be reserved for high risk people or where baseline CVC infection rates are high (> 15%). Further research is needed to identify high risk groups most likely to benefit.

Anti-Adhesion Elastomer Seal Coatings for Ultraviolet and Atomic Oxygen Protection

NASA Technical Reports Server (NTRS)

De Groh, Henry C., III; Puleo, Bernadette J.; Waters, Deborah L.; Miller, Sharon K.

2015-01-01

Radiation blocking sunscreen coatings have been developed for the protection of elastomer seals used in low-Earth-orbit (LEO). The coatings protect the seals from ultraviolet (UV) radiation and atomic oxygen (AO) damage. The coatings were developed for use on NASA docking seals. Docking seal damage from the UV and AO present in LEO can constrain mission time-line, flight mode options, and increases risk. A low level of adhesion is also required for docking seals so undocking push-off forces can be low. The coatings presented also mitigate this unwanted adhesion. Greases with low collected volatile condensable materials (CVCM) and low total mass loss (TML) were mixed with slippery and/or UV blocking powders to create the protective coatings. Coatings were applied at rates up to 2 milligrams per square centimeter. Coated seals were exposed to AO and UV in the NUV (near-UV) and UV-C wavelength ranges (300 to 400 nanometers and 254 nanometers, respectively). Ground based ashers were used to simulate the AO of space. The Sun's UV energy was mimicked assuming a nose forward flight mode, resulting in an exposure rate of 2.5 megajoules per square meter per day. Exposures between 0 and 147 megajoules per square meter (UV-C) and 245 megajoules per square meter (NUV) were accomplished. The protective coatings were durable, providing protection from UV after a simulated docking and undocking cycle. The level of protection begins to decline at coverage rates less than 0.9 milligrams per square centimeter. The leakage of seals coated with Braycote plus 20 percent Z-cote ZnO sunscreen increased by a factor of 40 after moderate AO exposure; indicating that this coating might not be suitable due to AO intolerance. Seals coated with DC-7-16.4 percent Z-cote ZnO sunscreen were not significantly affected by combined doses of 2 x 10 (sup 21) atoms per square AO with 73 megajoules per square meter UV-C. Unprotected seals were significantly damaged at UV-C exposures of 0.3 megajoules per square meter and DC-7-16.4 percent Z-cote coated seals were undamaged at all exposures up to the limits tested thus far which were 147 megajoules per square meter UV-C and 245 megajoules per square meter NUV. The coatings decreased adhesion sufficiently for docking seals at temperatures equal to or greater than -8 degrees Centigrade thus offer a simple and inexpensive way to mitigate adhesion.

41 CFR 102-75.575 - Who notifies non-profit organizations that surplus real property and related personal property to...

Code of Federal Regulations, 2014 CFR

2014-01-01

... organizations that surplus real property and related personal property to be used for self-help housing or... PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Property for Providing Self-Help Housing Or Housing Assistance § 102-75.575 Who notifies non-profit organizations that surplus real property...

41 CFR 102-75.575 - Who notifies non-profit organizations that surplus real property and related personal property to...

Code of Federal Regulations, 2010 CFR

2010-07-01

... organizations that surplus real property and related personal property to be used for self-help housing or... PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Property for Providing Self-Help Housing Or Housing Assistance § 102-75.575 Who notifies non-profit organizations that surplus real property...

41 CFR 102-75.575 - Who notifies non-profit organizations that surplus real property and related personal property to...

Code of Federal Regulations, 2012 CFR

2012-01-01

... organizations that surplus real property and related personal property to be used for self-help housing or... PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Property for Providing Self-Help Housing Or Housing Assistance § 102-75.575 Who notifies non-profit organizations that surplus real property...

41 CFR 102-75.575 - Who notifies non-profit organizations that surplus real property and related personal property to...

Code of Federal Regulations, 2011 CFR

2011-01-01

... organizations that surplus real property and related personal property to be used for self-help housing or... PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Property for Providing Self-Help Housing Or Housing Assistance § 102-75.575 Who notifies non-profit organizations that surplus real property...

41 CFR 102-75.575 - Who notifies non-profit organizations that surplus real property and related personal property to...

Code of Federal Regulations, 2013 CFR

2013-07-01

... organizations that surplus real property and related personal property to be used for self-help housing or... PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Property for Providing Self-Help Housing Or Housing Assistance § 102-75.575 Who notifies non-profit organizations that surplus real property...

41 CFR 105-72.407 - Property trust relationship.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Property trust relationship. 105-72.407 Section 105-72.407 Public Contracts and Property Management Federal Property... § 105-72.407 Property trust relationship. Real property, equipment, intangible property and debt...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

31 CFR 510.307 - Property; property interest.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Property; property interest. 510.307 Section 510.307 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... Definitions § 510.307 Property; property interest. The terms property and property interest include, but are...

31 CFR 510.307 - Property; property interest.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Property; property interest. 510.307 Section 510.307 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... Definitions § 510.307 Property; property interest. The terms property and property interest include, but are...

31 CFR 510.307 - Property; property interest.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Property; property interest. 510.307 Section 510.307 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... Definitions § 510.307 Property; property interest. The terms property and property interest include, but are...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

7 CFR 767.51 - Property abandonment.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AGRICULTURE SPECIAL PROGRAMS INVENTORY PROPERTY MANAGEMENT Property Abandonment and Personal Property Removal..., manage, and operate the abandoned security property, including marketing perishable security property on...

41 CFR 302-3.419 - For what property will my agency pay property management services?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false For what property will my agency pay property management services? 302-3.419 Section 302-3.419 Public Contracts and Property....419 For what property will my agency pay property management services? Your agency will only pay for...

36 CFR 1210.37 - Property trust relationship.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Property trust relationship. 1210.37 Section 1210.37 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS... Standards § 1210.37 Property trust relationship. Real property, equipment, intangible property and debt...

Property Differencing for Incremental Checking

NASA Technical Reports Server (NTRS)

Yang, Guowei; Khurshid, Sarfraz; Person, Suzette; Rungta, Neha

2014-01-01

This paper introduces iProperty, a novel approach that facilitates incremental checking of programs based on a property di erencing technique. Speci cally, iProperty aims to reduce the cost of checking properties as they are initially developed and as they co-evolve with the program. The key novelty of iProperty is to compute the di erences between the new and old versions of expected properties to reduce the number and size of the properties that need to be checked during the initial development of the properties. Furthermore, property di erencing is used in synergy with program behavior di erencing techniques to optimize common regression scenarios, such as detecting regression errors or checking feature additions for conformance to new expected properties. Experimental results in the context of symbolic execution of Java programs annotated with properties written as assertions show the e ectiveness of iProperty in utilizing change information to enable more ecient checking.

41 CFR 102-84.40 - What types of real property must I report for the Annual Real Property Inventory?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What types of real property must I report for the Annual Real Property Inventory? 102-84.40 Section 102-84.40 Public Contracts... REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.40 What types of real property must I...

41 CFR 102-84.40 - What types of real property must I report for the Annual Real Property Inventory?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What types of real property must I report for the Annual Real Property Inventory? 102-84.40 Section 102-84.40 Public Contracts... REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.40 What types of real property must I...

41 CFR 102-84.40 - What types of real property must I report for the Annual Real Property Inventory?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false What types of real property must I report for the Annual Real Property Inventory? 102-84.40 Section 102-84.40 Public Contracts... REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.40 What types of real property must I...

41 CFR 102-84.40 - What types of real property must I report for the Annual Real Property Inventory?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false What types of real property must I report for the Annual Real Property Inventory? 102-84.40 Section 102-84.40 Public Contracts... REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.40 What types of real property must I...

41 CFR 102-84.40 - What types of real property must I report for the Annual Real Property Inventory?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What types of real property must I report for the Annual Real Property Inventory? 102-84.40 Section 102-84.40 Public Contracts... REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.40 What types of real property must I...

41 CFR 102-75.995 - May Federal agencies dispose of dangerous property?

Code of Federal Regulations, 2013 CFR

2013-07-01

... dispose of dangerous property? 102-75.995 Section 102-75.995 Public Contracts and Property Management...-REAL PROPERTY DISPOSAL Abandonment, Destruction, or Donation to Public Bodies Dangerous Property § 102-75.995 May Federal agencies dispose of dangerous property? No, property that is dangerous to public...

41 CFR 102-75.995 - May Federal agencies dispose of dangerous property?

Code of Federal Regulations, 2012 CFR

2012-01-01

... dispose of dangerous property? 102-75.995 Section 102-75.995 Public Contracts and Property Management...-REAL PROPERTY DISPOSAL Abandonment, Destruction, or Donation to Public Bodies Dangerous Property § 102-75.995 May Federal agencies dispose of dangerous property? No, property that is dangerous to public...

41 CFR 102-75.995 - May Federal agencies dispose of dangerous property?

Code of Federal Regulations, 2014 CFR

2014-01-01

... dispose of dangerous property? 102-75.995 Section 102-75.995 Public Contracts and Property Management...-REAL PROPERTY DISPOSAL Abandonment, Destruction, or Donation to Public Bodies Dangerous Property § 102-75.995 May Federal agencies dispose of dangerous property? No, property that is dangerous to public...

41 CFR 102-75.995 - May Federal agencies dispose of dangerous property?

Code of Federal Regulations, 2010 CFR

2010-07-01

... dispose of dangerous property? 102-75.995 Section 102-75.995 Public Contracts and Property Management...-REAL PROPERTY DISPOSAL Abandonment, Destruction, or Donation to Public Bodies Dangerous Property § 102-75.995 May Federal agencies dispose of dangerous property? No, property that is dangerous to public...

41 CFR 102-75.995 - May Federal agencies dispose of dangerous property?

Code of Federal Regulations, 2011 CFR

2011-01-01

... dispose of dangerous property? 102-75.995 Section 102-75.995 Public Contracts and Property Management...-REAL PROPERTY DISPOSAL Abandonment, Destruction, or Donation to Public Bodies Dangerous Property § 102-75.995 May Federal agencies dispose of dangerous property? No, property that is dangerous to public...

41 CFR 102-75.240 - May excess real property be temporarily assigned/reassigned?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Utilization of Excess Real Property Temporary Utilization § 102-75.240... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false May excess real property...

41 CFR 102-38.75 - How may we sell personal property?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false How may we sell personal property? 102-38.75 Section 102-38.75 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

41 CFR 102-38.75 - How may we sell personal property?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false How may we sell personal property? 102-38.75 Section 102-38.75 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

41 CFR 102-38.75 - How may we sell personal property?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false How may we sell personal property? 102-38.75 Section 102-38.75 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

41 CFR 102-38.75 - How may we sell personal property?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false How may we sell personal property? 102-38.75 Section 102-38.75 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

41 CFR 102-38.75 - How may we sell personal property?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false How may we sell personal property? 102-38.75 Section 102-38.75 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

41 CFR 102-73.295 - What property transfer expenses must Federal agencies cover when acquiring real property?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What property transfer... Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 73-REAL ESTATE ACQUISITION Acquisition by Purchase or Condemnation...

7 CFR 277.13 - Property.

Code of Federal Regulations, 2010 CFR

2010-01-01

... the cost of the property to the current fair market value of the property. (3) Disposition. If the... the cost of the property to the current fair market value of the property, plus any shipping or... property to the current fair market value of the property, and for any reasonable shipping and interim...

26 CFR 301.6337-1 - Redemption of property.

Code of Federal Regulations, 2010 CFR

2010-04-01

... of property. (a) Before sale. Any person whose property has been levied upon shall have the right to... after the sale thereof. (2) Price. Such property or tract of property may be redeemed upon payment to... property) are purchased in the aggregate, the redemption price of the real property (or of each of the...

41 CFR 102-41.155 - Is unclaimed personal property available for transfer to another Federal agency?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Is unclaimed personal... and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT... transferred property then loses its identity as unclaimed property and becomes property of the Government, and...

41 CFR 102-75.735 - What happens after the disposal agency receives the transfer request from the Federal agency?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What happens after the... Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Property for...

41 CFR 102-78.15 - What are historic properties?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What are historic properties? 102-78.15 Section 102-78.15 Public Contracts and Property Management Federal Property Management... Preservation § 102-78.15 What are historic properties? Historic properties are those that are included in, or...

41 CFR 102-78.15 - What are historic properties?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What are historic properties? 102-78.15 Section 102-78.15 Public Contracts and Property Management Federal Property Management... Preservation § 102-78.15 What are historic properties? Historic properties are those that are included in, or...

41 CFR 102-75.1230 - How long does an agency have to indicate its interest in the property?

Code of Federal Regulations, 2010 CFR

2010-07-01

... screening of the real property and the time allotted for responding is less than 30 days. The Notice of... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Screening of Federal Real Property § 102-75.1230 How long...

41 CFR 102-75.585 - What action must the disposal agency take after an eligible public agency has submitted a plan of...

Code of Federal Regulations, 2010 CFR

2010-07-01

... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Property for Providing Self... disposal agency take after an eligible public agency has submitted a plan of use for property for a self...

41 CFR 102-37.80 - What happens to surplus property that isn't transferred for donation?

Code of Federal Regulations, 2010 CFR

2010-07-01

... property that isn't transferred for donation? 102-37.80 Section 102-37.80 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.80 What happens to surplus property that isn't transferred for donation? Surplus property not transferred for...

41 CFR 102-37.130 - What are a SASP's responsibilities in the donation of surplus property?

Code of Federal Regulations, 2010 CFR

2010-07-01

... responsibilities in the donation of surplus property? 102-37.130 Section 102-37.130 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY State Agency for Surplus Property (SASP) § 102-37.130 What are a SASP's responsibilities in the donation of surplus property? As a SASP, your...

41 CFR 102-37.130 - What are a SASP's responsibilities in the donation of surplus property?

Code of Federal Regulations, 2012 CFR

2012-01-01

... responsibilities in the donation of surplus property? 102-37.130 Section 102-37.130 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY State Agency for Surplus Property (SASP) § 102-37.130 What are a SASP's responsibilities in the donation of surplus property? As a SASP, your...

41 CFR 102-37.80 - What happens to surplus property that isn't transferred for donation?

Code of Federal Regulations, 2013 CFR

2013-07-01

... property that isn't transferred for donation? 102-37.80 Section 102-37.80 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.80 What happens to surplus property that isn't transferred for donation? Surplus property not transferred for...

41 CFR 102-37.130 - What are a SASP's responsibilities in the donation of surplus property?

Code of Federal Regulations, 2014 CFR

2014-01-01

... responsibilities in the donation of surplus property? 102-37.130 Section 102-37.130 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY State Agency for Surplus Property (SASP) § 102-37.130 What are a SASP's responsibilities in the donation of surplus property? As a SASP, your...

41 CFR 102-37.80 - What happens to surplus property that isn't transferred for donation?

Code of Federal Regulations, 2012 CFR

2012-01-01

... property that isn't transferred for donation? 102-37.80 Section 102-37.80 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.80 What happens to surplus property that isn't transferred for donation? Surplus property not transferred for...

41 CFR 102-37.80 - What happens to surplus property that isn't transferred for donation?

Code of Federal Regulations, 2014 CFR

2014-01-01

... property that isn't transferred for donation? 102-37.80 Section 102-37.80 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.80 What happens to surplus property that isn't transferred for donation? Surplus property not transferred for...

41 CFR 102-37.130 - What are a SASP's responsibilities in the donation of surplus property?

Code of Federal Regulations, 2011 CFR

2011-01-01

... responsibilities in the donation of surplus property? 102-37.130 Section 102-37.130 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY State Agency for Surplus Property (SASP) § 102-37.130 What are a SASP's responsibilities in the donation of surplus property? As a SASP, your...

41 CFR 102-37.80 - What happens to surplus property that isn't transferred for donation?

Code of Federal Regulations, 2011 CFR

2011-01-01

... property that isn't transferred for donation? 102-37.80 Section 102-37.80 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.80 What happens to surplus property that isn't transferred for donation? Surplus property not transferred for...

41 CFR 102-37.130 - What are a SASP's responsibilities in the donation of surplus property?

Code of Federal Regulations, 2013 CFR

2013-07-01

... responsibilities in the donation of surplus property? 102-37.130 Section 102-37.130 Public Contracts and Property... PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY State Agency for Surplus Property (SASP) § 102-37.130 What are a SASP's responsibilities in the donation of surplus property? As a SASP, your...

41 CFR 102-75.1200 - How may representatives of the homeless apply for the use of properties to assist the homeless?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false How may representatives....1200 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Use of Federal Real Property to...

41 CFR 102-75.975 - What happens if the property is not conveyed or disposed of during this time frame?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What happens if the... Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Management of Excess and Surplus Real Property...

15 CFR 744.22 - Restrictions on exports, reexports and transfers to persons whose property and interests in...

Code of Federal Regulations, 2014 CFR

2014-01-01

... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310..., reexports, and transfers to persons whose property and interests in property are blocked pursuant to...

15 CFR 744.22 - Restrictions on exports, reexports and transfers to persons whose property and interests in...

Code of Federal Regulations, 2012 CFR

2012-01-01

... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310..., reexports, and transfers to persons whose property and interests in property are blocked pursuant to...

15 CFR 744.22 - Restrictions on exports, reexports and transfers to persons whose property and interests in...

Code of Federal Regulations, 2013 CFR

2013-01-01

... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310..., reexports, and transfers to persons whose property and interests in property are blocked pursuant to...

15 CFR 744.22 - Restrictions on exports, reexports and transfers to persons whose property and interests in...

Code of Federal Regulations, 2011 CFR

2011-01-01

... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310..., reexports, and transfers to persons whose property and interests in property are blocked pursuant to...

15 CFR 744.22 - Restrictions on exports, reexports and transfers to persons whose property and interests in...

Code of Federal Regulations, 2010 CFR

2010-01-01

... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310... transfers to persons whose property and interests in property are blocked pursuant to Executive Orders 13310..., reexports, and transfers to persons whose property and interests in property are blocked pursuant to...

75 FR 61412 - Information Collection; Federal Excess Personal Property (FEPP) and Firefighter Property (FFP...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-05

... DEPARTMENT OF AGRICULTURE Forest Service Information Collection; Federal Excess Personal Property (FEPP) and Firefighter Property (FFP) Program Cooperative Agreements AGENCY: Forest Service, USDA... information collection, Federal Excess Personal Property (FEPP) and Firefighter Property (FFP) program...

41 CFR 109-45.303 - Reporting property for sale.

Code of Federal Regulations, 2011 CFR

2011-01-01

... sale. 109-45.303 Section 109-45.303 Public Contracts and Property Management Federal Property... AND DISPOSAL 45-SALE, ABANDONMENT, OR DESTRUCTION OF PERSONAL PROPERTY 45.3-Sale of Personal Property § 109-45.303 Reporting property for sale. ...

41 CFR 102-75.1250 - What if the agency is not quite sure it wants the property and needs more time to decide?

Code of Federal Regulations, 2010 CFR

2010-07-01

... not quite sure it wants the property and needs more time to decide? 102-75.1250 Section 102-75.1250 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Screening of Federal Real Property...

Intellectual Property Law as an Internal Limit on Intellectual Property Rights and Autonomous Source of Liability for Intellectual Property Owners

ERIC Educational Resources Information Center

Judge, Elizabeth F.

2007-01-01

This article considers the interplay between intellectual property rights and classic property rights raised by Hoffman v. Monsanto (2005) and advances the idea that intellectual property law can serve as an autonomous source of liability for intellectual property owners. The article develops the conceptual advantages of demarcating physical and…

41 CFR 109-1.5108 - Personal property records requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Personal property records requirements. 109-1.5108 Section 109-1.5108 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT REGULATIONS...

7 CFR 1955.128 - Appraisers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... type of properties (such as large farms and business property) requiring valuation. For Farmer Programs... REGULATIONS (CONTINUED) PROPERTY MANAGEMENT Disposal of Inventory Property Use of Contractors to Dispose of Inventory Property § 1955.128 Appraisers. (a) Real property. The State Director may authorize the County...

Analysis of horse movements from non-commercial horse properties in New Zealand.

PubMed

Rosanowski, S M; Cogger, N; Rogers, C W; Bolwell, C F; Benschop, J; Stevenson, M A

2013-09-01

To investigate property-level factors associated with the movement of horses from non-commercial horse properties, including the size and location of the property, number and reason for keeping horses. Using a cross-sectional survey 2,912 questionnaires were posted to randomly selected non-commercial horse properties listed in a rural property database. The survey collected information about the number of horses, and reasons for keeping horses on the property, and any movement of horses in the previous 12 months. Three property-level outcomes were investigated; the movement status of the property, the frequency of movement events, and the median distance travelled from a property. Associations were examined using logistic regression and Kruskal-Wallis analysis of variance. In total 62.0% (488/791) of respondents reported at least one movement event in the year prior to the survey, for a total of 22,050 movement events. The number of movement events from a property varied significantly by the number of horses on the property (p<0.02), while the median distance travelled per property varied significantly by both region (p<0.03) and property size (p<0.01). Region, property size, the number of horses kept, and keeping horses for competition, recreation, racing or as pets were all significantly associated with movement status in the multivariable analyses (p<0.001). This study showed that there are characteristics of non-commercial horse properties that influence movement behaviour. During an exotic disease outbreak the ability to identify properties with these characteristics for targeted control will enhance the effectiveness of control measures.

34 CFR 74.37 - Property trust relationship.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 34 Education 1 2011-07-01 2011-07-01 false Property trust relationship. 74.37 Section 74.37 Education Office of the Secretary, Department of Education ADMINISTRATION OF GRANTS AND AGREEMENTS WITH... Property Standards § 74.37 Property trust relationship. Real property, equipment, intangible property, and...

41 CFR 109-1.5205 - Personal property management system changes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Personal property management system changes. 109-1.5205 Section 109-1.5205 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT REGULATIONS...

41 CFR 102-84.45 - What types of real property are excluded from reporting for the Annual Real Property Inventory?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false What types of real property are excluded from reporting for the Annual Real Property Inventory? 102-84.45 Section 102-84.45...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.45 What types of...

41 CFR 102-84.45 - What types of real property are excluded from reporting for the Annual Real Property Inventory?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false What types of real property are excluded from reporting for the Annual Real Property Inventory? 102-84.45 Section 102-84.45...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.45 What types of...

41 CFR 102-84.45 - What types of real property are excluded from reporting for the Annual Real Property Inventory?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What types of real property are excluded from reporting for the Annual Real Property Inventory? 102-84.45 Section 102-84.45...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.45 What types of...

41 CFR 102-84.45 - What types of real property are excluded from reporting for the Annual Real Property Inventory?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What types of real property are excluded from reporting for the Annual Real Property Inventory? 102-84.45 Section 102-84.45...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.45 What types of...

41 CFR 102-84.45 - What types of real property are excluded from reporting for the Annual Real Property Inventory?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What types of real property are excluded from reporting for the Annual Real Property Inventory? 102-84.45 Section 102-84.45...) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 84-ANNUAL REAL PROPERTY INVENTORIES § 102-84.45 What types of...

41 CFR 102-75.1255 - What happens when more than one agency has a valid interest in the property?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What happens when more than one agency has a valid interest in the property? 102-75.1255 Section 102-75.1255 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY...

Review of research on the mechanical properties of the human tooth

PubMed Central

Zhang, Ya-Rong; Du, Wen; Zhou, Xue-Dong; Yu, Hai-Yang

2014-01-01

‘Bronze teeth' reflect the mechanical properties of natural teeth to a certain extent. Their mechanical properties resemble those of a tough metal, and the gradient of these properties lies in the direction from outside to inside. These attributes confer human teeth with effective mastication ability. Understanding the various mechanical properties of human teeth and dental materials is the basis for the development of restorative materials. In this study, the elastic properties, dynamic mechanical properties (visco-elasticity) and fracture mechanical properties of enamel and dentin were reviewed to provide a more thorough understanding of the mechanical properties of human teeth. PMID:24743065

41 CFR 101-1.102 - Federal Property Management Regulations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Federal Property Management Regulations. 101-1.102 Section 101-1.102 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS GENERAL 1-INTRODUCTION 1.1-Regulation...

41 CFR 101-1.101 - Federal Property Management Regulations System.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Federal Property Management Regulations System. 101-1.101 Section 101-1.101 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS GENERAL 1-INTRODUCTION 1.1...

48 CFR 245.7310-4 - Dangerous property.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Dangerous property. 245... Dangerous property. The following warning shall be included when it cannot be certified that the property is completely harmless: Dangerous Property Purchasers are warned that the property purchased may contain items...

26 CFR 1.166-10 - Reserve for guaranteed debt obligations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... property in satisfaction of the debt obligations. (3) Real or tangible personal property. Real or tangible... tangible personal property, between the dealer in that property and the customer with respect to that... in property and the customer with respect to the property. Delivery, financing installation...

41 CFR 109-1.5202 - Establishment of a personal property holdings baseline.

Code of Federal Regulations, 2010 CFR

2010-07-01

... personal property holdings baseline. 109-1.5202 Section 109-1.5202 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT...-1.5202 Establishment of a personal property holdings baseline. (a) If the contractor is a new...

41 CFR 102-37.440 - May donees acquire property for exchange?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false May donees acquire property for exchange? 102-37.440 Section 102-37.440 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 37...

41 CFR 102-41.120 - How long must we hold unclaimed personal property before disposition?

Code of Federal Regulations, 2011 CFR

2011-01-01

... unclaimed personal property before disposition? 102-41.120 Section 102-41.120 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 41-DISPOSITION OF SEIZED, FORFEITED, VOLUNTARILY ABANDONED, AND UNCLAIMED PERSONAL PROPERTY...

41 CFR 102-41.120 - How long must we hold unclaimed personal property before disposition?

Code of Federal Regulations, 2010 CFR

2010-07-01

... unclaimed personal property before disposition? 102-41.120 Section 102-41.120 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 41-DISPOSITION OF SEIZED, FORFEITED, VOLUNTARILY ABANDONED, AND UNCLAIMED PERSONAL PROPERTY...

14 CFR 1274.923 - Equipment and other property.

Code of Federal Regulations, 2010 CFR

2010-01-01

... share ratio. Jointly owned property shall be disposed of as agreed to by the parties. (d) Title to... maintain property management standards for Government property and otherwise manage such property as set... Officer, Finance, with three copies sent concurrently to the center Industrial Property Officer. The...

36 CFR 1207.31 - Real property.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Real property. 1207.31... GOVERNMENTS Post-Award Requirements Changes, Property, and Subawards § 1207.31 Real property. (a) Title. Subject to the obligations and conditions set forth in this section, title to real property acquired under...

41 CFR 105-71.131 - Real property.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Real property. 105-71... GOVERNMENTS 71.13-Post-Award Requirements/Changes, Property, and Subawards § 105-71.131 Real property. (a) Title. Subject to the obligations and conditions set forth in this section, title to real property...

36 CFR 1207.31 - Real property.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Real property. 1207.31... GOVERNMENTS Post-Award Requirements Changes, Property, and Subawards § 1207.31 Real property. (a) Title. Subject to the obligations and conditions set forth in this section, title to real property acquired under...

28 CFR 70.32 - Real property.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Real property. 70.32 Section 70.32...-PROFIT ORGANIZATIONS Post-Award Requirements Property Standards § 70.32 Real property. (a) Title to real property will vest in the recipient subject to the condition that the recipient use the real property for...

41 CFR 105-71.131 - Real property.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Real property. 105-71... GOVERNMENTS 71.13-Post-Award Requirements/Changes, Property, and Subawards § 105-71.131 Real property. (a) Title. Subject to the obligations and conditions set forth in this section, title to real property...

28 CFR 70.32 - Real property.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Real property. 70.32 Section 70.32...-PROFIT ORGANIZATIONS Post-Award Requirements Property Standards § 70.32 Real property. (a) Title to real property will vest in the recipient subject to the condition that the recipient use the real property for...

41 CFR 105-71.131 - Real property.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Real property. 105-71... GOVERNMENTS 71.13-Post-Award Requirements/Changes, Property, and Subawards § 105-71.131 Real property. (a) Title. Subject to the obligations and conditions set forth in this section, title to real property...

36 CFR 1207.31 - Real property.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Real property. 1207.31... GOVERNMENTS Post-Award Requirements Changes, Property, and Subawards § 1207.31 Real property. (a) Title. Subject to the obligations and conditions set forth in this section, title to real property acquired under...

28 CFR 70.32 - Real property.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Real property. 70.32 Section 70.32...-PROFIT ORGANIZATIONS Post-Award Requirements Property Standards § 70.32 Real property. (a) Title to real property will vest in the recipient subject to the condition that the recipient use the real property for...

28 CFR 70.32 - Real property.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Real property. 70.32 Section 70.32...-PROFIT ORGANIZATIONS Post-Award Requirements Property Standards § 70.32 Real property. (a) Title to real property will vest in the recipient subject to the condition that the recipient use the real property for...

28 CFR 70.32 - Real property.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Real property. 70.32 Section 70.32...-PROFIT ORGANIZATIONS Post-Award Requirements Property Standards § 70.32 Real property. (a) Title to real property will vest in the recipient subject to the condition that the recipient use the real property for...

41 CFR 105-71.131 - Real property.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Real property. 105-71... GOVERNMENTS 71.13-Post-Award Requirements/Changes, Property, and Subawards § 105-71.131 Real property. (a) Title. Subject to the obligations and conditions set forth in this section, title to real property...

41 CFR 105-71.131 - Real property.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Real property. 105-71... GOVERNMENTS 71.13-Post-Award Requirements/Changes, Property, and Subawards § 105-71.131 Real property. (a) Title. Subject to the obligations and conditions set forth in this section, title to real property...

36 CFR 72.40 - Historic properties.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Historic properties. 72.40 Section 72.40 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR URBAN... and Innovation § 72.40 Historic properties. Properties listed in or determined eligible for listing in...

36 CFR 520.3 - Preservation of property.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Preservation of property. 520.3 Section 520.3 Parks, Forests, and Public Property SMITHSONIAN INSTITUTION RULES AND REGULATIONS... Preservation of property. It is unlawful willfully to destroy, damage, or remove property or any part thereof...

26 CFR 1.737-4 - Anti-abuse rule.

Code of Federal Regulations, 2010 CFR

2010-04-01

... contributed property) for each year of the partnership, the fair market value of partnership property does not.... A contributes Property A1, nondepreciable real property with a fair market value of $10,000 and an... to the partnership Property A2, nondepreciable real property with a fair market value and adjusted...

41 CFR 102-75.550 - What does “self-help housing or housing assistance” mean?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Property for Providing Self-Help Housing Or Housing Assistance § 102-75.550 What does “self-help housing or housing assistance” mean? Property...

41 CFR 102-75.605 - What responsibilities does HUD have after receiving the disposal agency's assignment letter?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 75-REAL PROPERTY DISPOSAL Surplus Real Property Disposal Property for Providing Self-Help Housing Or Housing Assistance § 102-75.605 What responsibilities does HUD...

41 CFR 128-1.5002-8 - Property custodian (PC).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Property custodian (PC... Personal Property Management § 128-1.5002-8 Property custodian (PC). An individual responsible for the... required on all actions affecting the personal property within his jurisdiction. The designation as PC may...

41 CFR 128-1.5002-8 - Property custodian (PC).

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Property custodian (PC... Personal Property Management § 128-1.5002-8 Property custodian (PC). An individual responsible for the... required on all actions affecting the personal property within his jurisdiction. The designation as PC may...

41 CFR 101-30.403-1 - Reports of excess and surplus personal property.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Reports of excess and surplus personal property. 101-30.403-1 Section 101-30.403-1 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND...

41 CFR 109-1.5104 - Borrowing of personal property.

Code of Federal Regulations, 2012 CFR

2012-01-01

...-INTRODUCTION 1.51-Personal Property Management Standards and Practices § 109-1.5104 Borrowing of personal... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Borrowing of personal property. 109-1.5104 Section 109-1.5104 Public Contracts and Property Management Federal Property...

41 CFR 109-1.5104 - Borrowing of personal property.

Code of Federal Regulations, 2013 CFR

2013-07-01

...-INTRODUCTION 1.51-Personal Property Management Standards and Practices § 109-1.5104 Borrowing of personal... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Borrowing of personal property. 109-1.5104 Section 109-1.5104 Public Contracts and Property Management Federal Property...

41 CFR 109-1.5104 - Borrowing of personal property.

Code of Federal Regulations, 2011 CFR

2011-01-01

...-INTRODUCTION 1.51-Personal Property Management Standards and Practices § 109-1.5104 Borrowing of personal... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Borrowing of personal property. 109-1.5104 Section 109-1.5104 Public Contracts and Property Management Federal Property...

41 CFR 109-1.5104 - Borrowing of personal property.

Code of Federal Regulations, 2014 CFR

2014-01-01

...-INTRODUCTION 1.51-Personal Property Management Standards and Practices § 109-1.5104 Borrowing of personal... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Borrowing of personal property. 109-1.5104 Section 109-1.5104 Public Contracts and Property Management Federal Property...

41 CFR 109-42.1102-51 - Suspect personal property.

Code of Federal Regulations, 2013 CFR

2013-07-01

....11-Special Types of Hazardous Material and Certain Categories of Property § 109-42.1102-51 Suspect... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Suspect personal property. 109-42.1102-51 Section 109-42.1102-51 Public Contracts and Property Management Federal Property...