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Sample records for absorbable collagen sponge

  1. Complication rates in patients using absorbable collagen sponges in third molar extraction sockets: a retrospective study.

    PubMed

    Cho, Hoon; Jung, Hwi-Dong; Kim, Bok-Joo; Kim, Chul-Hoon; Jung, Young-Soo

    2015-02-01

    The purpose of this study is to retrospectively evaluate the postoperative complication rates for absorbable type-I collagen sponge (Ateloplug; Bioland) use in third molar extraction. From January to August 2013, 2,697 total patients undergoing third molar extraction and type-I collagen sponge application in the Department of Oral and Maxillofacial Surgery at Yonsei University Dental Hospital (1,163 patients) and Dong-A University Hospital (1,534 patients) were evaluated in a retrospective study using their operation and medical records. A total of 3,869 third molars in 2,697 patients were extracted and the extraction sockets packed with type-I collagen sponges to prevent postoperative complications. As a result, the overall complication rate was 4.52%, with 3.00% experiencing surgical site infection (SSI), 1.14% showing alveolar osteitis, and 0.39% experiencing hematoma. Of the total number of complications, SSI accounted for more than a half at 66.29%. Compared to previous studies, this study showed a relatively low incidence of complications. The use of type-I collagen sponges is recommended for the prevention of complications after third molar extraction.

  2. Comparison between a β-tricalcium phosphate and an absorbable collagen sponge carrier technology for rhGDF-5-stimulated periodontal wound healing/regeneration.

    PubMed

    Kim, Young-Taek; Wikesjö, Ulf M E; Jung, Ui-Won; Lee, Jung-Seok; Kim, Tae-Gyun; Kim, Chong-Kwan

    2013-06-01

    The objective of this study is to compare a candidate β-tricalcium phosphate (β-TCP) carrier technology with the absorbable collagen sponge (ACS) benchmark to support recombinant human growth/differentiation factor-5 (rhGDF-5)-stimulated periodontal wound healing/regeneration. Routine, bilateral, critical-size (5-mm), 1-wall, intrabony periodontal defects were surgically created in the mandibular premolar region in 10 beagle dogs. Five animals received rhGDF-5/β-TCP and five animals received rhGDF-5/ACS, with a total of 20 μg rhGDF-5 per defect. The animals were euthanized for histologic and histometric analyses at 8 weeks postsurgery. Both rhGDF-5/ACS and rhGDF-5/β-TCP stimulated the formation of functionally oriented periodontal ligament, cellular mixed fiber cementum, and woven/lamellar bone. Bone regeneration (height and area) was significantly greater for the rhGDF-5/β-TCP construct than for the rhGDF-5/ACS (3.26 ± 0.30 mm versus 2.22 ± 0.82 mm, P <0.01; and 10.45 ± 2.26 mm(2) versus 5.62 ± 2.39 mm(2), P <0.01, respectively). Cementum formation ranged from 3.83 ± 0.73 mm to 3.03 ± 1.18 mm without significant differences between groups. Root resorption/ankylosis was not observed. The β-TCP carrier technology significantly enhanced rhGDF-5-stimulated bone formation compared with the ACS benchmark in this discriminating periodontal defect model. The structural integrity of the β-TCP carrier, preventing compression while providing a framework for bone ingrowth, may account for the observed results.

  3. Effect of collagen sponge and fibrin glue on bone repair

    PubMed Central

    SANTOS, Thiago de Santana; ABUNA, Rodrigo Paolo Flores; de ALMEIDA, Adriana Luisa Gonçalves; BELOTI, Marcio Mateus; ROSA, Adalberto Luiz

    2015-01-01

    ABSTRACT The ability of hemostatic agents to promote bone repair has been investigated using in vitro and in vivo models but, up to now, the results are inconclusive. Objective In this context, the aim of this study was to compare the potential of bone repair of collagen sponge with fibrin glue in a rat calvarial defect model. Material and Methods Defects of 5 mm in diameter were created in rat calvariae and treated with either collagen sponge or fibrin glue; untreated defects were used as control. At 4 and 8 weeks, histological analysis and micro-CT-based histomorphometry were carried out and data were compared by two-way ANOVA followed by Student-Newman-Keuls test when appropriated (p≤0.05). Results Three-dimensional reconstructions showed increased bone formation in defects treated with either collagen sponge or fibrin glue compared with untreated defects, which was confirmed by the histological analysis. Morphometric parameters indicated the progression of bone formation from 4 to 8 weeks. Additionally, fibrin glue displayed slightly higher bone formation rate when compared with collagen sponge. Conclusion Our results have shown the benefits of using collagen sponge and fibrin glue to promote new bone formation in rat calvarial bone defects, the latter being discreetly more advantageous. PMID:26814464

  4. Local rhBMP-12 on an Absorbable Collagen Sponge as an Adjuvant Therapy for Rotator Cuff Repair - A Phase 1, Randomized, Standard of Care Control, Multicenter Study: Safety and Feasibility.

    PubMed

    Greiner, Stefan; Ide, Junji; Van Noort, Arthur; Mochizuki, Yu; Ochi, Hiroshi; Marraffino, Shannon; Sridharan, Sudhakar; Rudicel, Sally; Itoi, Eiji

    2015-08-01

    Recombinant human bone morphogenetic protein-12 (rhBMP-12) has been shown to induce tendon and ligament formation in rats and to improve tendon healing; however, the safety and feasibility of implanting rhBMP-12/absorbable collagen sponge (ACS) in humans are not known. To investigate the safety and feasibility of rhBMP-12 on an ACS as an adjuvant therapy in open rotator cuff repair. Randomized controlled trial; Level of evidence, 2. This study consisted of 20 patients with full-thickness rotator cuff tears. Patients were randomized either to standard of care (SOC) treatment (open rotator cuff repair) or to receive 0.015 mg/mL rhBMP-12/ACS and SOC treatment during their open rotator cuff repair (rhBMP-12/ACS group) at a rate of 1/4 SOC/rhBMP-12/ACS. The feasibility of implanting the product and the safety of the product were evaluated during the 1-year follow-up period. The evaluation involved up to 10 postoperative visits, which included physical examinations, radiographs, computed tomography (CT) scans, magnetic resonance imaging (MRI) scans with an emphasis on heterotopic ossification (HO), pharmacokinetics, immunogenicity, laboratory evaluations, and local and systemic adverse events at specified time points. Small amounts of HO were seen on follow-up CT scans in 10 of 16 patients in the rhBMP-12/ACS group and in 2 of 3 patients in the SOC group. HO did not increase at 26 weeks and was not associated with any adverse events or unsatisfactory clinical outcomes. Pharmacokinetics demonstrated that circulating levels of rhBMP-12 were not detectable after administration. Five of 16 patients showed a postoperative immunogenic response but did not show any correlating adverse events. Complete healing of the rotator cuff was observed in 14 of 16 patients; 2 of 16 imaging results could not be analyzed because of artifacts in the rhBMP-12 group on MRI scans. In the SOC group, 1 of 4 patients showed a retear at 12 weeks after surgery. The use of rhBMP-12/ACS has been shown

  5. Enhancement of healing in osteochondral defects by collagen sponge implants.

    PubMed

    Speer, D P; Chvapil, M; Volz, R G; Holmes, M D

    1979-10-01

    Implants of porous, highly cross-linked collagen sponge (CS) were tested for their capacity to enhance the healing of osteochondral defects in rabbits. Comparison was made to the healing of similar defects with polyvinyl alcohol sponge (PVAS) implants and with no implants (CONT). Evaluation was carried out up to 44 weeks following implantation and included observation of host cellular response, biodegradability of implant, gross appearance of restored joint surface, collagenous architecture of repair tissue, and properties of the junctions of implants and host articular cartilage, subchondral bone, and medullary bone. Collagen sponge proved most effective in promoting healing of osteochondral defects with fibrous and fibrocartilaginous tissue over restored subchondral bone. Collagen sponge showed many desirable properties as a potential material for biologic resurfacing of damaged joints. These properties included porosity, biodegradability, biocompatability, ability to mechanically protect cells and matrix while directing cell ingrowth, and an available chemical technology for modifying its biomechanical and biological properties. Comparative analysis of results of healing of CS, PVAS, and CONT osteochondral defects suggest rational design criteria for implant materials to improve their effectiveness in restoration of articular surfaces.

  6. The acceptance of the collagen sponge diaphragm as an intravaginal contraceptive in human volunteers.

    PubMed

    Chvapil, M; Heine, M W; Horton, H

    1976-12-01

    Two types of highly resilient and liquid-absorbent collagen sponge contraceptives (CSC) in the shape of cylindrical cups (6 cm wide and 2.5 cm thick) were evaluated for acceptance as an intravaginal contraceptive method for a period of 3 months in 27 volunteers. Parameters such as retention, odor, irritation, itching, discharge, and convenience for the user and her sexual partner were tested. Average retention time was 7 to 9 days (range, 2 to 28 days); still, most sexually active volunteers preferred to remove the CSC every 3 to 4 days, rinse them in tap water, and reinsert them. Odor was noticed by users in 4% of the tested sponges and in 30% of all volunteers by medical personnel at the time of removal of the CSC from the vagina. No irritation, itching, or discharge was reported. The CSC alone did not cause any inconvenience to the user or partner, while the CSC with inserted rubber ring was felt by both partners and was found to be dislocated. This study indicates good acceptance of the CSC in intravaginal use. Studies to evaluate the efficacy of collagen sponges as mechanical contraceptive barriers are in progress.

  7. Collagen-coated cellulose sponge: three dimensional matrix for tissue culture of Walker tumor 256.

    PubMed

    Leighton, J; Justh, G; Esper, M; Kronenthal, R L

    1967-03-10

    Three-dimensional growth of large populations of cells in vitro has been observed in the interstices of a matrix consisting of collagen-coated cellu lose sponge. The growth of Walker tumor 256 in this composite matrix is com pared with that found in a matrix composed of either cellulose sponge alone or collagen sponge alone. The composite matrix is superior to either one. Collagen coated cellulose sponge may provide a simple tool for the study of social interaction of cells in the formation of organized elementary tissue structures.

  8. [Healing of a deep skin wound using a collagen sponge as dressing in the animal experiment].

    PubMed

    Sedlarik, K M; Schoots, C; Oosterbaan, J A; Klopper, J P

    1992-10-01

    The high number of available wound dressing materials as well as the scientific reports about the topic indicates that the problem of an ideal wound dressing is not jet solved. In the last thirty years lot of scientific reports about collagen as wound covering has been published. The positive effect of collagen by his application on a wound ist well known. We investigated the effect of a collagen sponge on healing of full thickness skin wound in guinea pig. The animals were divided in two control groups and two experimental groups. In the control group there were air exposed wounds and another wounds covered with paraffin gauze. In the experimental groups were such wounds covered with natural reconstituted collagen sponge as well as wounds covered with chemically prepared collagen sponge with hexamethyldiisocyanat. The results were compared. The air exposed wounds healed in 50 days, the wounds covered with paraffin gauze healed in 48 days. By covering the wounds with collagen sponge the healing was shortened in 24 or 27 days respectively. Not only the healing time was shortened but also the quality of the wound repair by dressing the wounds with collagen sponge was enhanced.

  9. In vivo comparison of jellyfish and bovine collagen sponges as prototype medical devices.

    PubMed

    Widdowson, Jonathan P; Picton, Alex J; Vince, Valerie; Wright, Chris J; Mearns-Spragg, Andrew

    2018-05-01

    Jellyfish have emerged as a source of next generation collagen that is an attractive alternative to existing sources, such as bovine and porcine, due to a plentiful supply and providing a safer source through lack of bovine spongiform encephalopathy (BSE) transmission risk and potential viral vectors, both of which could be transmitted to humans. Here we compare collagen implantable sponges derived for the first time from the Rhizostoma pulmo jellyfish. A further novelty for the research was that there was a comparison for sponges that were either uncrosslinked or crosslinked using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), and an assessment on how this affected resorption, as well as their biocompatibility compared to bovine type I collagen sponges. The scaffolds were prepared and examined using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) and scanning electron microscopy (SEM). The samples were implanted in adult male Wistar rats for in vivo experimentation. Both crosslinked and uncrosslinked jellyfish collagen sponges showed a significant reduction in histopathology scores over the course of the study, whereas the bovine collagen sponge scores were not significantly reduced. Both jellyfish collagen sponges and the bovine sponge were tolerated well by the hosts, and a recovery was visible in all samples, suggesting that R. pulmo jellyfish-derived collagen could offer compelling biocompatibility with wound healing applications. We also demonstrate that noncrosslinked samples could be safer with better resorption times than crosslinked samples. © 2017 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1524-1533, 2018. © 2017 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc.

  10. In vivo comparison of jellyfish and bovine collagen sponges as prototype medical devices

    PubMed Central

    Picton, Alex J.; Vince, Valerie; Wright, Chris J.; Mearns‐Spragg, Andrew

    2017-01-01

    Abstract Jellyfish have emerged as a source of next generation collagen that is an attractive alternative to existing sources, such as bovine and porcine, due to a plentiful supply and providing a safer source through lack of bovine spongiform encephalopathy (BSE) transmission risk and potential viral vectors, both of which could be transmitted to humans. Here we compare collagen implantable sponges derived for the first time from the Rhizostoma pulmo jellyfish. A further novelty for the research was that there was a comparison for sponges that were either uncrosslinked or crosslinked using 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide hydrochloride (EDC), and an assessment on how this affected resorption, as well as their biocompatibility compared to bovine type I collagen sponges. The scaffolds were prepared and examined using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) and scanning electron microscopy (SEM). The samples were implanted in adult male Wistar rats for in vivo experimentation. Both crosslinked and uncrosslinked jellyfish collagen sponges showed a significant reduction in histopathology scores over the course of the study, whereas the bovine collagen sponge scores were not significantly reduced. Both jellyfish collagen sponges and the bovine sponge were tolerated well by the hosts, and a recovery was visible in all samples, suggesting that R. pulmo jellyfish‐derived collagen could offer compelling biocompatibility with wound healing applications. We also demonstrate that noncrosslinked samples could be safer with better resorption times than crosslinked samples. © 2017 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1524–1533, 2018. PMID:28741862

  11. Cross-linked collagen sponges loaded with plant polyphenols with inhibitory activity towards chronic wound enzymes.

    PubMed

    Antonio, Francesko; Guillem, Rocasalbas; Sonia, Touriño; Clara, Mattu; Piergiorgio, Gentile; Valeria, Chiono; Gianluca, Ciardelli; Tzanov, Tzanko

    2011-10-01

    Collagen sponges loaded with polyphenols from Hamamelis virginiana were investigated as active materials for chronic wound dressings, evaluating in vitro the inhibition of two major enzymes that impair the wound healing process - myeloperoxidase (MPO) and collagenase. Prior to polyphenols loading, collagen was cross-linked with genipin to improve its biostability. The effect of genipin cross-linking and polyphenol concentration in the development of mechanically and enzymatically stable sponges was studied. The tensile strength of the cross-linked collagen increased with the increase of the cross-linking degree, coupled to decrease in the elongation and the swelling capacity of the sponges. The stability of the sponges to collagenase digestion reached maximum when 1 mM genipin was used. However, the biostability decreased more than 10-fold after loading the sponges with polyphenols (0.5 mg/mL), nevertheless, this effect was partially overcome using higher concentration of polyphenols (1 and 2 mg/mL) to inhibit collagenase. Moreover, the polyphenols released from the sponges were sufficient for complete inhibition of MPO activity. No considerable cytotoxicity of the genipin cross-linked collagen loaded with polyphenols was observed evaluating the NIH 3T3 fibroblasts viability. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Development and in vitro evaluation of expandable gastroretentive dosage forms based on compressed collagen sponges.

    PubMed

    Gröning, R; Cloer, C; Müller, R S

    2006-07-01

    The objective of this study was to develop and evaluate new collagen gastroretentive dosage forms (GRDFs) which expand in the stomach after contact with gastric fluids. The GRDFs should remain in the stomach for a prolonged period of time due to their size. The dosage forms were prepared from collagen sponges. The sponges were manufactured by freeze-drying a riboflavin-containing collagen solution. A computer controlled material supply was constructed to transport precompressed collagen into a tablet machine. A second type of tablet was manufactured by combining compressed collagen sponges with hydrophilic matrix layers of hydroxypropylmethylcellulose. Matrix layers containing captopril or aciclovir were developed. In vitro experiments were performed with both types of dosage forms. The collagen tablets expand within a few minutes after contact with artificial gastric juice and form a drug delivery system with a size of 8 mm x 18 mm x 60 mm. Riboflavin is released over 16 h. If two layer tablets are used, the release of aciclovir or captopril can be controlled by the composition of the sustained release layer.

  13. Biochemical and biophysical characterization of collagens of marine sponge, Ircinia fusca (Porifera: Demospongiae: Irciniidae).

    PubMed

    Pallela, Ramjee; Bojja, Sreedhar; Janapala, Venkateswara Rao

    2011-07-01

    Collagens were isolated and partially characterized from the marine demosponge, Ircinia fusca from Gulf of Mannar (GoM), India, with an aim to develop potentially applicable collagens from unused and under-used resources. The yield of insoluble, salt soluble and acid soluble forms of collagens was 31.71 ± 1.59, 20.69 ± 1.03, and 17.38 ± 0.87 mg/g dry weight, respectively. Trichrome staining, Scanning & Transmission Electron microscopic (SEM & TEM) studies confirmed the presence of collagen in the isolated, terminally globular irciniid filaments. The partially purified (gel filtration chromatography), non-fibrillar collagens appeared as basement type collagenous sheets under light microscopy whereas the purified fibrillar collagens appeared as fibrils with a repeated band periodicity of 67 nm under Atomic Force Microscope (AFM). The non-fibrillar and fibrillar collagens were seen to have affinity for anti-collagen type IV and type I antibodies raised against human collagens, respectively. The macromolecules, i.e., total protein, carbohydrate and lipid contents within the tissues were also quantified. The present information on the three characteristic irciniid collagens (filamentous, fibrillar and non-fibrillar) could assist the future attempts to unravel the therapeutically important, safer collagens from marine sponges for their use in pharmaceutical and cosmeceutical industries. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Inflammatory response study of gellan gum impregnated duck's feet derived collagen sponges.

    PubMed

    Song, Jeong Eun; Lee, Seon Eui; Cha, Se Rom; Jang, Na Keum; Tripathy, Nirmalya; Reis, Rui L; Khang, Gilson

    2016-10-01

    Tissue engineered biomaterials have biodegradable and biocompatible properties. In this study, we have fabricated sponges using duck's feet derived collagen (DC) and gellan gum (GG), and further studied its inflammatory responses. The as-prepared duck's feet DC/GG sponges showed the possibility of application as a tissue engineering material through in vitro and in vivo experiments. The physical and chemical properties of sponges were characterized by compression strength, porosity, and scanning electron microscopy, etc. In vitro cell viability were investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay. An inflammatory response was studied after seeding RAW264.7 cells on as-fabricated sponges using reverse transcriptase-polymerase chain reaction. In vivo studies were carried out by implanting in subcutaneous nude mouse followed by extraction, histological staining. Collectively, superior results were showed by DC/GG sponges than GG sponge in terms of physical property and cell proliferation and thus can be considered as a potential candidate for future tissue engineering applications.

  15. Evaluation of Anterior Vertebral Interbody Fusion Using Osteogenic Mesenchymal Stem Cells Transplanted in Collagen Sponge.

    PubMed

    Yang, Wencheng; Dong, Youhai; Hong, Yang; Guang, Qian; Chen, Xujun

    2016-05-01

    The study used a rabbit model to achieve anterior vertebral interbody fusion using osteogenic mesenchymal stem cells (OMSCs) transplanted in collagen sponge. We investigated the effectiveness of graft material for anterior vertebral interbody fusion using a rabbit model by examining the OMSCs transplanted in collagen sponge. Anterior vertebral interbody fusion is commonly performed. Although autogenous bone graft remains the gold-standard fusion material, it requires a separate surgical procedure and is associated with significant short-term and long-term morbidity. Recently, mesenchymal stem cells from bone marrow have been studied in various fields, including posterolateral spinal fusion. Thus, we hypothesized that cultured OMSCs transplanted in porous collagen sponge could be used successfully even in anterior vertebral interbody fusion. Forty mature male White Zealand rabbits (weight, 3.5-4.5 kg) were randomly allocated to receive one of the following graft materials: porous collagen sponge plus cultured OMSCs (group I); porous collagen sponge alone (group II); autogenous bone graft (group III); and nothing (group IV). All animals underwent anterior vertebral interbody fusion at the L4/L5 level. The lumbar spine was harvested en bloc, and the new bone formation and spinal fusion was evaluated using radiographic analysis, microcomputed tomography, manual palpation test, and histologic examination at 8 and 12 weeks after surgery. New bone formation and bony fusion was evident as early as 8 weeks in groups I and III. And there was no statistically significant difference between 8 and 12 weeks. At both time points, by microcomputed tomography and histologic analysis, new bone formation was observed in both groups I and III, fibrous tissue was observed and there was no new bone in both groups II and IV; by manual palpation test, bony fusion was observed in 40% (4/10) of rabbits in group I, 70% (7/10) of rabbits in group III, and 0% (0/10) of rabbits in both groups

  16. Collagen-PVA aligned nanofiber on collagen sponge as bi-layered scaffold for surface cartilage repair.

    PubMed

    Lin, Hsin-Yi; Tsai, Wen-Chi; Chang, Shih-Hsing

    2017-05-01

    Researchers have made bi-layered scaffolds but mostly for osteochondral repairs. The anatomic structure of human cartilage has different zones and that each has varying matrix morphology and mechanical properties is often overlooked. Two bi-layered collagen-based composites were made to replicate the superficial and transitional zones of an articular cartilage. Aligned and random collagen-PVA nanofibers were electrospun onto a freeze-dried collagen sponge to make the aligned and random composites, respectively. The morphology, swelling ratio, degradation and tensile properties of the two composites were examined. Primary porcine chondrocytes were cultured on the composites for three weeks and their proliferation and secretion of glycosaminoglycan (GAG) and type II collagen were measured. The influences of the cell culture on the tensile properties of the composites were studied. The nanofiber layer remained adhered to the sponge after three weeks of cell culture. Both composites lost 30-35% of their total weight in a saline buffer after three weeks. The tensile strength and Young's modulus of both composites increased after three weeks of chondrocyte culture (p < 0.05). The aligned composite with extracellular matrix deposition had a Young's modulus (0.35 MPa) similar to that of articular cartilage reported in literature (0.36-0.8 MPa). The chondrocytes on both aligned and random composites proliferated and secreted similar amounts of GAG and type II collagen. They were seen embedded in lacunae after three weeks. The aligned composite may be more suitable for articular cartilage repair because of the higher tensile strength from the aligned nanofibers on the surface that can better resist wear.

  17. Intra-articular implantation of gentamicin impregnated collagen sponge causes joint inflammation and impaired renal function in dogs.

    PubMed

    Hayes, Galina; Gibson, Tom; Moens, Noel M M; Nykamp, Stephanie; Wood, Darren; Foster, Robert; Lerer, Asaf

    2016-01-01

    Gentamicin impregnated collagen sponge (GICS) can be used to treat intra-articular surgical site infections. High local concentrations of gentamicin can be reached for short periods; however the collagen vehicle may persist for much longer periods. We wished to determine the effect of sponge implantation on joint inflammation and renal function. Eighteen medium sized mixed breed research dogs of hound type were randomized to two groups; arthroscopic implantation of GICS at gentamicin dose = 6 mg/kg (n = 9) or sham operation (n = 9). Endpoints consisted of joint inflammation measured by synovial fluid cell counts and cytokine concentrations; lameness measured by force plate asymmetry indices; and renal function measured by glomerular filtration rate (GFR) study. The prevalence of lesions associated with aminoglycoside nephrotoxicity was assessed by renal biopsy and transmission electron microscopy. Gentamicin impregnated collagen sponge implantation caused joint inflammation (p <0.01), lameness (p = 0.04), and decreased GFR (p = 0.04). No difference was observed in the prevalence of renal lesions on biopsy between the treatment and control groups (p = 0.49). Gentamicin impregnated collagen sponge implantation causes joint inflammation and lameness as well as GFR reductions at the dose assessed. Gentamicin impregnated collagen sponge are not recommended for intra-articular implantation in dogs.

  18. In vitro retinoid binding and release from a collagen sponge material in a simulated intravaginal environment.

    PubMed

    Dorr, R T; Surwit, E A; Droegemueller, W; Alberts, D S; Meyskens, F L; Chvapil, M

    1982-11-01

    Four in vitro preparations were constructed to simulate the intravaginal release of two retinoids, all-trans-retinoic acid (t-RA) and 13-cis-retinoic acid (c-RA), from a 0.7% collagen sponge diaphragm insert. Four t-RA concentrations, 0.019, 0.05, 0.1, and 0.15% in methanol were added to the sponge. The release into an artificial vaginal fluid was monitored serially over 72 h by serial analysis for t-RA and c-RA using high-pressure liquid chromatography. In each preparation, retinoid release was immediate and noncontinuous. At 37 degrees C, the retinoids were stable for at least 48 h. Trans-retinoic acid was the predominant retinoid recovered. Only trace amounts of the cis-isomer were released. Peak t-RA levels were 20 microM after 0.01%, 60-80 microM after 0.05%, 100-200 microM after 0.1%, and 320 microM after 0.15%. When the vaginal fluid bath was changed after 5 h, no further significant retinoid release occurred. There was significant loss of up to 70% of the applied t-RA into the collagen sponge. The retinoid binding was concentration dependent (higher binding with higher concentrations) and was maximal only after 24 h of co-incubation. The discontinuous release of t-RA and the high degree of binding to collagen would seem to preclude use of the diaphragm insert as a vaginal drug delivery system, at least for retinoids.

  19. Effects of cross-linking on mechanical, biological properties and biodegradation behavior of Nile tilapia skin collagen sponge as a biomedical material.

    PubMed

    Sun, Leilei; Li, Bafang; Yao, Di; Song, Wenkui; Hou, Hu

    2018-04-01

    The objective of this study was to explore the effects of dehydrothermal treatment (DHT) and glutaraldehyde (GTA) cross-linking on mechanical, biological properties and biodegradation behavior of Nile tilapia skin collagen sponge fabricated by freeze-drying technology. It was found that the GTA cross-linked collagen sponge exhibited a higher degree of cross-linking in comparison with DHT. The extent of increased tensile strength as well as hygroscopicity indicated that GTA cross-linking was superior to DHT in mechanical properties and liquid absorption, which was attributed to different cross-linking mechanisms. Hygroscopicity assay indicated that cross-linking could improve stability of collagen in solutions. No obvious changes in porosity and blood coagulation time were observed whether cross-linking or not. Results from collagenase biodegradation assay in vitro illustrated that GTA-treated collagen sponge was more resistant to collagenase biodegradation, while DHT exhibited negligible resistance. In addition, photochemical stability of collagen sponge was studied by Fourier transforms infrared spectroscopy (FTIR), which indicated that both cross-linking treatments could not change the backbone structure of collagen. Furthermore, the microstructure of collagen sponge was stable after cross-linking. The highly porous and interconnected structure of collagen sponge was helpful to the absorption of wound exudates, supplement of oxygen and cell proliferation, accompanied with good blood compatibility, which indicated that our fabricated collagen sponge could be applied in biomedical materials field as wound dressings. Copyright © 2018. Published by Elsevier Ltd.

  20. Effect of absorbable gelatin sponge in the middle ear: in vitro and in vivo animal model.

    PubMed

    Goncalves, Stefania; Chiossone-Kerdel, Juan Armando; Bianco, Andrea S; Ercolino, Jose M; Hernandez-Rojas, Jorge

    2015-01-01

    GelitaSpon gelatin sponge (GS) showed faster reabsorption than gelfoam (GF) in vitro, and GS-packed middle ears resulted in a faster hearing recovery and less inflammation than the ears packed with GF soaked in saline. Soaking GF sponges with boric acid (BA) appeared to offset the inflammatory response of saline-soaked GF, making this inflammatory response comparable to that of GS-packed ears. To describe the reabsorption and inflammatory effects of absorbable gelatin sponge in the middle ear. For in vitro evaluation, GF and GS were used as disks immersed in saline solution or 3% BA and placed in gel. Images were captured with a microscope and processed using image processing Toolbox. For in vivo tests, 16 female albino Sprague Dawley rats were divided into four groups: bulla opening; GF + 0.9% saline; GF + BA; and GS + 0.9% saline. An anterior approach to the right bulla was used for surgery. Preoperative and postoperative auditory brainstem response thresholds were measured. In vitro, there was marked degradation of GF by day 14, while GS showed complete degradation by the third day. In vivo, hearing recovery occurred by day 21. GF produced a more severe inflammatory response, which could be reduced by treating the GF with BA.

  1. Preparation and characterization of marine sponge collagen nanoparticles and employment for the transdermal delivery of 17beta-estradiol-hemihydrate.

    PubMed

    Nicklas, Martina; Schatton, Wolfgang; Heinemann, Sascha; Hanke, Thomas; Kreuter, Jörg

    2009-09-01

    Transdermal administration of estradiol offers advantages over oral estrogens for hormone replacement therapy regarding side effects by bypassing the hepatic presystemic metabolism. The objective of this study was to develop nanoparticles of Chondrosia reniformis sponge collagen as penetration enhancers for the transdermal drug delivery of 17beta-estradiol-hemihydrate in hormone replacement therapy. Collagen nanoparticles were prepared by controlled alkaline hydrolysis and characterized using atomic force microscopy and photon correlation spectroscopy. Estradiol-hemihydrate was loaded to the nanoparticles by adsorption to their surface, whereupon a drug loading up to 13.1% of sponge collagen particle mass was found. After incorporation of drug-loaded nanoparticles in a hydrogel, the estradiol transdermal delivery from the gel was compared with that from a commercial gel that did not contain nanoparticles. Saliva samples in postmenopausal patients showed significantly higher estradiol levels after application of the gel with nanoparticles. The area under the curve (AUC) for estradiol time-concentration curves over 24 hours was 2.3- to 3.4-fold higher and estradiol levels 24 hours after administration of estradiol were at least twofold higher with the nanoparticle gel. The hydrogel with estradiol-loaded collagen nanoparticles enabled a prolonged estradiol release compared to a commercial gel and yielded a considerably enhanced estradiol absorption. Consequently, sponge collagen nanoparticles represent promising carriers for transdermal drug delivery.

  2. Local application of an ibandronate/collagen sponge improves femoral fracture healing in ovariectomized rats

    PubMed Central

    Liu, Yansong; Hou, Zhiyong; Chen, Wei; Jin, Lin; Tian, Ye; Ju, Linlin; Liu, Bo; Dong, Tianhua; Zhang, Fei

    2017-01-01

    Non-union is a major clinical problem in the healing of fractures, especially in patients with osteoporosis. The systemic administration of drugs is time consuming and large doses are demanding and act slowly, whereas local release acts rapidly, increases the quality and quantity of the bone tissue. We hypothesize that local delivery demonstrates better therapeutic effects on an osteoporotic fracture. The aim of this paper is to investigate the effect of the local application of ibandronate loaded with a collagen sponge on regulating bone formation and remodeling in an osteoporotic rat model of fracture healing. We found that the local delivery of ibandronate exhibited excellent effects on improving the bone microarchitecture and suppressed effects on bone remodeling. At 4 weeks, more callus formation and improvement of mechanical character and microstructure were observed in a local delivery via μCT, mechanical test, histological research and serum analysis. The suppression of bone remodeling was compared with a systemic treatment at 12 weeks, and the structural mechanical properties and microarchitecture were also improved with local delivery. This research identifies an earlier, safer and integrated approach for local delivery of ibandronate with collagen and provides a better strategy for the treatment of osteoporotic fracture in rats. PMID:29108027

  3. Cost analysis of gentamicin-impregnated collagen sponges in preventing sternal wound infection post cardiac surgery.

    PubMed

    Joshi, V; Vaja, R; Richens, D

    2016-01-01

    The use of antibiotic-impregnated sponges (Collatamp) during cardiac surgery is controversial. We analysed the cost-effectiveness of its selective use in patients at high-risk of sternal wound infection (SWI). Postoperative costs were analysed in two groups of patients undergoing heart surgery between 2011 and 2013: those with SWI (group 1) and in high-risk patients without SWI (group 2). The potential cost of gentamicin-impregnated collagen sponges (GCS) use in high-risk patients was compared with our current practice. We identified 1,251 patients with at least one recognised risk factor for developing SWI in this period. Of these, 18 developed SWI (incidence 1.4%). The median postoperative cost per patient without SWI was £9,617. The additional cost per patient incurred by SWI was £4,860.75. The annual additional cost for treating patients with SWI was £43,749. With a 50% reduction in SWI, the annual additional cost of treating these patients would be reduced to £21,873. The cost of GCS is £80 per patient. Adding this to £21,873 gives a potential total cost of £71,913 in the treated high-risk cohort. In our practice the annual cost of treating SWI in high-risk patients without use of GCS is lower than the annual cost of using GCS in all high-risk patients (£43,749 versus £71,913) if it produces a 50% reduction in SWI. The reduction in the incidence of SWI poses no economic benefit when the cost of the product is factored in.

  4. Fish scale collagen sponge incorporated with Macrotyloma uniflorum plant extract as a possible wound/burn dressing material.

    PubMed

    Muthukumar, Thangavelu; Prabu, P; Ghosh, Kausik; Sastry, Thotapalli Parvathaleswara

    2014-01-01

    Application of plant extracts for the burn/wound treatment is followed over the decades as a common practice and it is an important aspect in clinical management. In this study porous collagen sponges (CS) were prepared using fish scales and were incorporated with mupirocin (CSM) and extracts of Macrotyloma uniflorum (CSPE) separately to impart antimicrobial activity to the sponges. The results showed that the addition of plant extract increased the tensile strength of CSPE and stability against collagenase enzyme. FTIR studies have shown the incorporation of plant extract in CSPE, SEM studies have revealed the porous nature of the sponges and XRD patterns have shown the retention of collagen triple helical structure even after the addition of plant extract. CSPE and CSM have exhibited antimicrobial properties. The sponges prepared were analysed for their in vitro biocompatibility studies using fibroblasts and keratinocyte cell lines and the results have shown their biocompatible nature. Based on the results obtained, CS, CSM and CSPE may be tried as a burn/wound dressing materials, initially, in small animals in vivo. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Biophysicochemical evaluation of chitosan-hydroxyapatite-marine sponge collagen composite for bone tissue engineering.

    PubMed

    Pallela, Ramjee; Venkatesan, Jayachandran; Janapala, Venkateswara Rao; Kim, Se-Kwon

    2012-02-01

    Tricomponent scaffold systems prepared by natural materials especially of marine origin are gaining much attention nowadays for the application in bone tissue engineering. A novel scaffold (Chi-HAp-MSCol) containing chitosan (Chi), hydroxyapatite (HAp) derived from Thunnus obesus bone and marine sponge (Ircinia fusca) collagen (MSCol) was prepared using freeze-drying and lyophilization method. This biomimetic scaffold, along with the Chi and Chi-HAp scaffolds were characterized biophysicochemically for their comparative significance in bone grafting applications. The structural composition of the chitosan, Chi-Hap, and Chi-HAp-MSCol scaffolds were characterized by Fourier Transform Infrared spectroscopy. The porosity, water uptake, and retention abilities of the composite scaffolds decreased, whereas Thermogravimetric and Differential Thermal Analyses results revealed the increase in thermal stability in the scaffold because of the highly stable HAp and MSCol. Homogeneous dispersion of HAp and MSCol in chitosan matrix with interconnected porosity of 60-180 μm (Chi-HAp) and 50-170 μm (Chi-HAp-MSCol) was observed by Scanning Electron Microscopy, X-ray diffraction, and optical microscopy. Cell proliferation in composite scaffolds was relatively higher than pure chitosan when observed by MTT assay and Hoechst staining in vitro using MG-63 cell line. These observations suggest that the novel Chi-HAp-MSCol composite scaffolds are promising biomaterials for matrix-based bone repair and bone augmentation. Copyright © 2011 Wiley Periodicals, Inc.

  6. Collagen Sponge Functionalized with Chimeric Anti-BMP-2 Monoclonal Antibody Mediates Repair of Critical-Size Mandibular Continuity Defects in a Nonhuman Primate Model

    PubMed Central

    Xie, Yilin; Su, Yingying; Tang, Jianxia; Goh, Bee Tin; Saigo, Leonardo; Zhang, Chunmei; Wang, Jinsong; Khojasteh, Arash; Wang, Songlin

    2017-01-01

    Antibody-mediated osseous regeneration (AMOR) has been introduced by our research group as a tissue engineering approach to capture of endogenous growth factors through the application of specific monoclonal antibodies (mAbs) immobilized on a scaffold. Specifically, anti-Bone Morphogenetic Protein- (BMP-) 2 mAbs have been demonstrated to be efficacious in mediating bone repair in a number of bone defects. The present study sought to investigate the application of AMOR for repair of mandibular continuity defect in nonhuman primates. Critical-sized mandibular continuity defects were created in Macaca fascicularis locally implanted with absorbable collagen sponges (ACS) functionalized with chimeric anti-BMP-2 mAb or isotype control mAb. 2D and 3D analysis of cone beam computed tomography (CBCT) imaging demonstrated increased bone density and volume observed within mandibular continuity defects implanted with collagen scaffolds functionalized with anti-BMP-2 mAb, compared with isotype-matched control mAb. Both CBCT imaging and histologic examination demonstrated de novo bone formation that was in direct apposition to the margins of the resected bone. It is hypothesized that bone injury may be necessary for AMOR. This is evidenced by de novo bone formation adjacent to resected bone margins, which may be the source of endogenous BMPs captured by anti-BMP-2 mAb, in turn mediating bone repair. PMID:28401163

  7. Pichia pastoris production of a prolyl 4-hydroxylase derived from Chondrosia reniformis sponge: A new biotechnological tool for the recombinant production of marine collagen.

    PubMed

    Pozzolini, Marina; Scarfì, Sonia; Mussino, Francesca; Salis, Annalisa; Damonte, Gianluca; Benatti, Umberto; Giovine, Marco

    2015-08-20

    Prolyl 4-hydroxylase (P4H) is a α2β2 tetramer catalyzing the post-translational hydroxylation of prolines in collagen. Its recombinant production is mainly pursued to realize biotechnological tools able to generate animal contaminant-free hydroxylated collagen. One promising candidate for biomedical applications is the collagen extracted from the marine sponge Chondrosia reniformis, because of its biocompatibility and because is devoid of the health risks associated with bovine and porcine collagens. Here we report on the production and selection, by enzymatic and biomolecular analyses, of a triple transformed Pichia pastoris strain expressing a stable P4H tetramer derived from C. reniformis sponge and a hydroxylated non fibrillar procollagen polypeptide from the same animal. The percentage of recombinant procollagen hydroxylated prolines inside the transformed yeast was of 36.3% analyzed by mass spectrometry indicating that the recombinant enzyme is active on its natural substrate inside the yeast cell host. Furthermore, the recombinant sponge P4H has the ability to hydroxylate its natural substrate in both X and Y positions in the Xaa-Yaa-Gly collagenous triplets. In conclusion this Pichia system seems ideal for high-level production of hydroxylated sponge- or marine-derived collagen polypeptides as well as of conotoxins or other marine proteins of high pharmacological interest needing this particular post-translational modification. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. The effect of lysophosphatidic acid using a hydrogel or collagen sponge carrier on bone healing in dogs.

    PubMed

    Might, Kelly R; Martinez, Steven A; Karin, Norman; Lin, Genyao; Tarasevich, Barbara; Pool, Roy R

    2016-07-19

    The purposes of this study were to determine: 1) the efficacy of polycaprolactone-g-polyethylene glycol (PCL-g-PEG) and polylactic-co-glycolic acid (PLGA-g-PEG) hydrogels and an absorbable collagen sponge (ACS) as carriers for lysophosphatidic acid (LPA), 2) the effect of LPA on bone healing in dogs, and 3) the ideal dose of LPA to maximally stimulate bone healing. Bilateral ulnar ostectomies were performed on purpose bred dogs. Control defects were filled with a PCL-g-PEG or PLGA-g-PEG hydrogel, or a saline soaked ACS. Contralateral defects were filled with a PCL-g-PEG or PLGA-g-PEG hydrogel, or an ACS with each carrying differing concentrations of an LPA solution. Dual-energy X-ray absorptiometry (DXA) was performed. Total bone area (TBA), mineral density (BMD), and mineral content (BMC) were determined at each time point. Relationships between the effect of treatment over time on TBA, BMC and BMD were determined. Phase 1 - There was no significant difference in DXA-based TBA (p = 0.09), BMC (p = 0.33), or BMD (p = 0.74) over time between LPA treatments, or between the LPA treated and control groups TBA (p = 0.95), BMC (p = 0.99), or BMD (p = 0.46). Phase 2 - There was no significant difference over time between LPA treatments in DXA-based TBA (p = 0.33), BMC (p = 0.45), or BMD (p = 0.43), or between the LPA treated and control groups TBA (p = 0.94), BMC (p = 0.38), or BMD (p = 0.17). Phase 3 - There was no significant difference over time between LPA treatments in DXA-based TBA (p = 0.78), BMC (p = 0.88), or BMD (p = 0.35), or between the LPA treated and control groups TBA (p = 0.07), BMC (p = 0.85), or BMD (p = 0.06). There was a significant increase in TBA (p <0.0001) and BMC (p = 0.0014), but a significant decrease in BMD (p <0.0001) was noted over time when all groups were combined. Although LPA has shown promise as an osteoinductive agent in research, its performance as a bone graft substitute, as utilized in this study, is unsupported. Further studies are

  9. [Absorbable shanching satin rb-bFGF prepreg sheet and expansion hemostatic sponge together to cure epistaxis with blood disease].

    PubMed

    Liu, Hua; Gao, Zhanmei; Song, Yang; Lu, Mancun

    2014-01-01

    This study investigated the effects and Numerical Rating Pain Scale (NRS) of using absorbable shanching satin rb-bFGF prepreg sheet and expansion hemostatic sponge together nasal packing in the control of epistaxis with blood disease, and compared it with traditional vaseline gauze. Ninety-six blood disease patient with epistaxis were enrolled between January 2009 and February 2011, they were divided into two groups at random, and differently treated with absorbable shanching satin rb-bFGF prepreg sheet and the vaseline gauze nasal packing for haemostasis. Then haemostasis efficacy,the hemorrhage rate after nasal packing removed and host response, such as nasal pain and headache, which evaluated pain degrees against NRS, were all observed. There was no significant difference between the two groups of the haemostatic effect. But the hemorrhage rate of treatment group was obviously lower than that of the control group after paching,in addition, host responses, such as nasal pain and headache, remarkably better than the control group, the difference had statistical significance. It is indicate that absorbable shanching satin rb-bFGF prepreg sheet presents reliable hemostasis effect, good biocompatibility and compliance; the pain and headache caused by packing are superior to vaseline gauze. Moreover, this method avoids the direct touch of vaseline gauze with nasal mucosal wound, and reduce hemorrhage after packing. Absorbable shanching satin rb-bFGF prepreg sheet and expansion hemostatic sponge together is better to select the nasal packing material for blood disease patient with epistaxis.

  10. Effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of hydroxyapatite-collagen composites as artificial bone materials.

    PubMed

    Yunoki, Shunji; Sugiura, Hiroaki; Ikoma, Toshiyuki; Kondo, Eiji; Yasuda, Kazunori; Tanaka, Junzo

    2011-02-01

    The aim of this study was to evaluate the effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of porous hydroxyapatite (HAp)-collagen composites as artificial bone materials. Seven types of porous HAp-collagen composites were prepared from HAp nanocrystals and dense collagen fibrils. Their densities and HAp/collagen weight ratios ranged from 122 to 331 mg cm⁻³ and from 20/80 to 80/20, respectively. The flexural modulus and strength increased with an increase in density, reaching 2.46 ± 0.48 and 0.651 ± 0.103 MPa, respectively. The porous composites with a higher collagen-matrix density exhibited much higher mechanical properties at the same densities, suggesting that increasing the collagen-matrix density is an effective way of improving the mechanical properties. It was also suggested that other structural factors in addition to collagen-matrix density are required to achieve bone-like mechanical properties. The in vivo absorbability of the composites was investigated in bone defects of rabbit femurs, demonstrating that the absorption rate decreased with increases in the composite density. An exhaustive increase in density is probably limited by decreases in absorbability as artificial bones.

  11. One-step fabrication of novel superhydrophobic and superoleophilic sponge with outstanding absorbency and flame-retardancy for the selective removal of oily organic solvent from water

    NASA Astrophysics Data System (ADS)

    Xiang, Yuqian; Pang, Youyou; Jiang, Xiaomei; Huang, Jie; Xi, Fengna; Liu, Jiyang

    2018-01-01

    Absorbent materials integrated with superhydrophobicity, superoleophilicity and flame-retardancy are highly desired in the adsorption/removal of flammable oils/organic compounds as well as reducing the risk of fire and explosion. Here, one-step fabrication of novel superhydrophobic and superoleophilic sponge with outstanding absorbency and flame-retardancy was presented. Using raw melamine (ME) sponge as the supporting matrix, the formation of polydopamine (PDA) nanoaggregates via in-situ self-polymerization of high-concentrated dopamine and the covalent grafting of hydrophobic n-dodecylthiol (DT) onto PDA were combined in a feasible alkaline water/ethanol medium. As investigated by scanning electron microscopy (SEM) and X-ray energy-dispersive spectroscopy (EDS), the as-prepared ME/PDA/DT sponge possessed hierarchical structure with submicron PDA nanoaggregates containing DT motif (low surface energy) on 3D interconnected porous network. It exhibited superhydrophobic (water contact angle 157.7°) and superoleophilic (oily/organic solvent contact angle 0° properties. Owing to the highly porous structure, superhydrophobic property, chemical and mechanical stability, the ME/PDA/DT sponge exhibited outstanding absorbency properties of oily organic solvents including fast absorption kinetics, high absorption capacity, and easy reusability. Also, the ME/PDA/DT sponge could be used for one-line continuous organic solvent/water separation. More interestingly, the ME/PDA/DT sponge demonstrated improved flame-retardant property as compared to the intrinsic flame-retardant nature of the raw melamine sponge. Consequently, the risk of fire and explosion was expected to reduce when the fabricated sponge was used as an absorbent for flammable oils and organic compounds. The ease of the one-step superhydrophobic/superoleophilic modification and the promising feature of the obtained materials exhibit great potential for application in oils/organic solvents clean-up.

  12. Promising efficacy of Escherichia coli recombinant human bone morphogenetic protein-2 in collagen sponge for ectopic and orthotopic bone formation and comparison with mammalian cell recombinant human bone morphogenetic protein-2.

    PubMed

    Kim, In Sook; Lee, Eui Nam; Cho, Tae Hyung; Song, Yun Mi; Hwang, Soon Jung; Oh, Ji Hye; Park, Eun Kyung; Koo, Tai Young; Seo, Young-Kwon

    2011-02-01

    Nonglycosylated recombinant human bone morphogenetic protein (rhBMP)-2 prepared in Escherichia coli (E. coli rhBMP-2) has recently been considered as an alternative to mammalian cell rhBMP-2. However, its clinical use is still limited owing to lack of evidence for osteogenic activity comparable with that of mammalian cell rhBMP-2 via microcomputed tomography-based analysis. Therefore, this study aimed to evaluate the ability of E. coli rhBMP-2 in absorbable collagen sponge to form ectopic and orthotopic bone and to compare it to that of mammalian rhBMP-2. In vitro investigation was performed to study osteoblast differentiation of human mesenchymal stromal cells. Both types of rhBMP-2 enhanced proliferation, alkaline phosphatase activity, and matrix mineralization of human mesenchymal stromal cells at similar levels. Similar tendencies were observed in microcomputed tomography analysis, which determined bone volume, fractional bone volume, trabecular thickness, trabecular separation, bone mineral density, and other characteristics. Histology from an in vivo osteoinductivity test and from a rat calvarial defect model demonstrated a dose-dependent increase in local bone formation. The E. coli rhBMP-2 group (5 μg) not only induced complete regeneration of an 8-mm critical-sized defect at 4 weeks, but also led to new bone with the same bone mineral density as normal bone at 8 weeks, with the same efficiency as that of mammalian cell rhBMP-2 (5 μg). These uniformly favorable results provide evidence that the osteogenic activity of E. coli rhBMP-2 is not inferior to that of mammalian cell rhBMP-2 despite its low solubility and lack of gylcosylation. These results suggest that the application of E. coli rhBMP-2 in absorbable collagen sponge may be a promising equivalent to mammalian cell rhBMP-2 in bone tissue engineering.

  13. Clinical and radiographic assessment of transforaminal lumbar interbody fusion using HEALOS collagen-hydroxyapatite sponge with autologous bone marrow aspirate.

    PubMed

    Carter, Jason D; Swearingen, Alan B; Chaput, Christopher D; Rahm, Mark D

    2009-06-01

    Studies have suggested that the use of bone marrow aspirate (BMA) with HEALOS (DePuy Spine, Raynham, MA), a collagen-hydroxyapatite sponge (CHS), is an effective substitute for autologous iliac crest bone graft when used in fusion procedures of the lumbar spine. To assess clinical and radiographic outcomes after implantation of BMA/CHS in patients undergoing transforaminal lumbar interbody fusion (TLIF) with posterolateral fusion (PLF). Case series radiographic outcome study. Twenty patients. Radiographs/computed tomography (CT) scans. From September 2003 to October 2004, 20 patients (22 interbody levels) were implanted with BMA/CHS via TLIF/PLF with interbody cages and posterior pedicle screws. All patients were retrospectively identified and invited for a 2-year prospective follow-up. Plain radiographs with dynamic films and CT scans were taken, and fusion was assessed in a blinded manner. Follow-up averaged 27 months (range: 24-29). Primary diagnosis included spondylolisthesis (17 patients), scoliosis with asymmetric collapse (2 patients), and postdiscectomy foraminal stenosis (1 patient). The overall fusion rate was 95% (21/22 levels, 19/20 patients). Anteriorly bridging bone was observed in 91% of the anteriorly fused levels (20/22), of which 65% (13/20) occurred through and around the cage and 35% (7/20) around the cage only. Unilateral or bilateral bridging of the posterior fusion masses was observed in 91% (20/22), with 55% occurring bilaterally (12/22). In 4 (18%) cases, bridging only occurred either posteriorly (2 cases) or anteriorly (2 cases). Complications included one deep wound infection. At the 2-year follow-up, BMA/CHS showed acceptable fusion rates in patients undergoing TLIF/PLF, and can be considered as an alternative source of graft material.

  14. Prevention of peridural fibrosis using a cyclooxygenase-2 inhibitor (nonsteroidal anti-inflammatory drug) soaked in absorbable gelatin sponge: an experimental comparative animal model.

    PubMed

    Sae-Jung, Surachai; Jirarattanaphochai, Kitti

    2013-07-15

    Experimental study. To evaluate the efficacy and safety of peridural parecoxib-soaked absorbable gelatin sponge, and cellulose membrane on peridural fibrosis prevention in an animal model. Postoperative peridural fibrosis is one of the causes of failed back surgery syndrome. Nonsteroidal anti-inflammatory drugs inhibit the inflammatory response, while an absorbable gelatin sponge or cellulose membrane interposes between the dura and the paraspinal muscle to staunch the surgical bleeding. These mechanisms may prevent peridural fibrosis. Forty L5-L6 laminectomized adult Sprague-Dawley rats were randomly allocated into 4 groups. The high parecoxib group received 6 mg of parecoxib soaked into an absorbable gelatin sponge placed over the dura. The low parecoxib group was given 2 mg of parecoxib soaked into an absorbable gelatin sponge. The dura in the cellulose group was covered with a cellulose membrane, while the control group received normal saline drip before surgical wound closure. All rats were killed at 6 weeks for histopathological assessment. The fibroblast density, inflammatory cell density, fibrous adherence, and adverse events were quantified. The obtained results were analyzed statistically. The respective mean fibroblast density in the high parecoxib, low parecoxib, cellulose, and control groups was 217.77 ± 51.76, 317.51 ± 126.92, 321.80 ± 90.94, and 328.48 ± 73.41 cells/mm², while the respective mean inflammatory cell density was 539.65 ± 236.52, 910.17 ± 242.59, 1011.84 ± 239.30, and 1261.78 ± 319.68 cells/mm². The mean fibroblast and inflammatory cell densities of the high parecoxib group were significantly lower than the control. The high parecoxib group also showed statistically less fibrous adherence than low parecoxib, cellulose, and control groups. The high-dose parecoxib-soaked absorbable gelatin sponge can prevent peridural fibrosis without complications. The low-dose parecoxib and cellulose membrane provided no significant benefit vis

  15. Collagen from the Marine Sponges Axinella cannabina and Suberites carnosus: Isolation and Morphological, Biochemical, and Biophysical Characterization.

    PubMed

    Tziveleka, Leto-Aikaterini; Ioannou, Efstathia; Tsiourvas, Dimitris; Berillis, Panagiotis; Foufa, Evangelia; Roussis, Vassilios

    2017-05-29

    In search of alternative and safer sources of collagen for biomedical applications, the marine demosponges Axinella cannabina and Suberites carnosus , collected from the Aegean and the Ionian Seas, respectively, were comparatively studied for their insoluble collagen, intercellular collagen, and spongin-like collagen content. The isolated collagenous materials were morphologically, physicochemically, and biophysically characterized. Using scanning electron microscopy and transmission electron microscopy the fibrous morphology of the isolated collagens was confirmed, whereas the amino acid analysis, in conjunction with infrared spectroscopy studies, verified the characteristic for the collagen amino acid profile and its secondary structure. Furthermore, the isoelectric point and thermal behavior were determined by titration and differential scanning calorimetry, in combination with circular dichroism spectroscopic studies, respectively.

  16. Efficacy of 50 Hz electromagnetic fields on human epidermal stem cell transplantation seeded in collagen sponge scaffolds for wound healing in a murine model.

    PubMed

    Bai, Wen-Fang; Xu, Wei-Cheng; Zhu, Hong-Xiang; Huang, Hong; Wu, Bo; Zhang, Ming-Sheng

    2017-04-01

    To explore the possible efficacy of electromagnetic fields (EMF) for skin tissue engineering, effects of EMF exposure on epidermal stem cells (ESC) seeded in collagen sponge scaffolds for wound healing in a murine model were investigated. The wound models of a full-thickness defect established with 36 7 ∼ 8-week-old nude mice were randomly divided into three groups: a control group, an ESC-only group, and an ESC with EMF exposure group (frequency of 50 Hz, magnetic induction of 5 mT, 60 min per day for 20 days). ESC were separated from human foreskin and cultured in vitro, and then transplanted with collagen sponge scaffolds as a delivery vehicle to wounds of the ESC-only group, and ESC with EMF exposure group was exposed to EMF after ESC transplantation. Effects of EMF on morphological changes and expression of β1 integrin in regenerated skins were observed. Wound healing rates and healing times were collected to evaluate the efficacy of repairment. Results showed that human ESC were successfully transplanted to nude mice, which facilitated the formation of intact skin on nude mice. In contrast to other groups, the wound healing of ESC with EMF exposure group was the fastest (P < 0.05), the structure of regenerated skins was more mature, and it contained more continuity in the number of viable cell layers and rich hair follicles' structure. These results suggest that the use of 50 Hz EMF as a non-invasive treatment can accelerate wound healing of ESC transplantation, and restore structural integrity of regenerated skin. Bioelectromagnetics. 38:204-212,2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  17. Hypoxia Is a Critical Parameter for Chondrogenic Differentiation of Human Umbilical Cord Blood Mesenchymal Stem Cells in Type I/III Collagen Sponges

    PubMed Central

    Gómez-Leduc, Tangni; Desancé, Mélanie; Hervieu, Magalie; Legendre, Florence; Ollitrault, David; de Vienne, Claire; Herlicoviez, Michel; Galéra, Philippe; Demoor, Magali

    2017-01-01

    Umbilical cord blood (UCB) is an attractive alternative to bone marrow for isolation of mesenchymal stem cells (MSCs) to treat articular cartilage defects. Here, we set out to determine the growth factors (bone morphogenetic protein 2 (BMP-2) and transforming growth factor-β (TGF-β1)) and oxygen tension effects during chondrogenesis of human UCB-MSCs for cartilage engineering. Chondrogenic differentiation was induced using 3D cultures in type I/III collagen sponges with chondrogenic factors in normoxia (21% O2) or hypoxia (<5% O2) for 7, 14 and 21 days. Our results show that UCB-MSCs can be committed to chondrogenesis in the presence of BMP-2+TGF-β1. Normoxia induced the highest levels of chondrocyte-specific markers. However, hypoxia exerted more benefit by decreasing collagen X and matrix metalloproteinase-13 (MMP13) expression, two chondrocyte hypertrophy markers. However, a better chondrogenesis was obtained by switching oxygen conditions, with seven days in normoxia followed by 14 days in hypoxia, since these conditions avoid hypertrophy of hUCB-MSC-derived chondrocytes while maintaining the expression of chondrocyte-specific markers observed in normoxia. Our study demonstrates that oxygen tension is a key factor for chondrogenesis and suggests that UBC-MSCs 3D-culture should begin in normoxia to obtain a more efficient chondrocyte differentiation before placing them in hypoxia for chondrocyte phenotype stabilization. UCB-MSCs are therefore a reliable source for cartilage engineering. PMID:28885597

  18. 21 CFR 886.4790 - Ophthalmic sponge.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ophthalmic sponge. 886.4790 Section 886.4790 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4790 Ophthalmic sponge. (a) Identification. An ophthalmic sponge is a device that is an absorbant sponge, pad, or spear made of folded gauze, cotton...

  19. Efficacy and safety of a porcine collagen sponge for cranial neurosurgery: a prospective case-control study.

    PubMed

    Brandão, Rafael Augusto Castro Santiago; Costa, Bruno Silva; Dellaretti, Marcos Antonio; de Carvalho, Gervásio Teles C; Faria, Marcello Penholate; de Sousa, Atos Alves

    2013-01-01

    The use of dural grafts is very useful when primary dural closure cannot be achieved. Our primary objective was to study the incidence of postoperative cerebrospinal fluid leak, including fistula and pseudomeningocele, and postoperative infection by comparing autologous material and a new collagen graft. A prospective nonrandomized study with a new collagen-based product derived from porcine cells (Peridry) was performed. It was used for dural replacement in 50 patients who underwent a variety of neurosurgical procedures requiring the use of a dural graft. These results were compared with a control group of 50 patients who were treated with autologous duraplasty material. The follow-up period was 3 months. Postoperative overall cerebrospinal fluid fistula occurred in 6% of both groups. No patient in the collagen group developed any sort of infection. One patient in the control developed osteomyelitis in the bone flap. The new collagen-based product derived from porcine cells (Peridry), compared with an autologous tissue, is safe, effective, easy to use, as well as time saving in cranial neurosurgery. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Scoring system to guide decision making for the use of gentamicin-impregnated collagen sponge to prevent deep sternal wound infection.

    PubMed

    Benedetto, Umberto; Raja, Shahzad G

    2014-11-01

    The effectiveness of the routine retrosternal placement of a gentamicin-impregnated collagen sponge (GICS) implant before sternotomy closure is currently a matter of some controversy. We aimed to develop a scoring system to guide decision making for the use of GICS to prevent deep sternal wound infection. Fast backward elimination on predictors, including GICS, was performed using the Lawless and Singhal method. The scoring system was reported as a partial nomogram that can be used to manually obtain predicted individual risk of deep sternal wound infection from the regression model. Bootstrapping validation of the regression models was performed. The final populations consisted of 8750 adult patients undergoing cardiac surgery through full sternotomy during the study period. A total of 329 patients (3.8%) received GICS implant. The overall incidence of deep sternal wound infection was lower among patients who received GICS implant (0.6%) than patients who did not (2.01%) (P=.02). A nomogram to predict the individual risk for deep sternal wound infection was developed that included the use of GICS. Bootstrapping validation confirmed a good discriminative power of the models. The scoring system provides an impartial assessment of the decision-making process for clinicians to establish if GICS implant is effective in reducing the risk for deep sternal wound infection in individual patients undergoing cardiac surgery through full sternotomy. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  1. Phase II Trial of β-All-trans-Retinoic Acid for Cervical Intraepithelial Neoplasia Delivered via a Collagen Sponge and Cervical Cap

    PubMed Central

    Graham, Vivian; Surwit, Earl S.; Weiner, Sheldon; Meyskens, Frank L.

    1986-01-01

    Retinoids are effective suppressors of the phenotypic development of cancer in many animal systems, whether the process is initiated by chemical, physical or viral carcinogens. Cases of cervical intraepithelial neoplasia are excellent for studying the effectiveness of retinoids as chemopreventive agents because the process can be closely followed by serial colposcopic and pathologic (cytology or biopsy) means and changes in the condition safely monitored. We have previously conducted a phase I study of trans-retinoic acid (Tretinoin) given topically by a collagen sponge and cervical cap. A dose of 0.372% was selected for phase II trial. We have treated 20 patients with topical retinoic acid, and a complete response with total regression of disease was obtained in 50%. Systemic and cervical side effects were mild and vaginal side effects moderate but tolerable. These results provide a clinical basis for a randomized, double-blind phase III study to definitely answer the question of whether retinoic acid is an effective chemopreventive agent for cervical cancer. ImagesFigure. 1. PMID:3765597

  2. The Effect of Interferon-γ and Zoledronate Treatment on Alpha-Tricalcium Phosphate/Collagen Sponge-Mediated Bone-Tissue Engineering

    PubMed Central

    Li, Peiqi; Hashimoto, Yoshiya; Honda, Yoshitomo; Arima, Yoshiyuki; Matsumoto, Naoyuki

    2015-01-01

    Inflammatory responses are frequently associated with the expression of inflammatory cytokines and severe osteoclastogenesis, which significantly affect the efficacy of biomaterials. Recent findings have suggested that interferon (IFN)-γ and zoledronate (Zol) are effective inhibitors of osteoclastogenesis. However, little is known regarding the utility of IFN-γ and Zol in bone tissue engineering. In this study, we generated rat models by generating critically sized defects in calvarias implanted with an alpha-tricalcium phosphate/collagen sponge (α-TCP/CS). At four weeks post-implantation, the rats were divided into IFN-γ, Zol, and control (no treatment) groups. Compared with the control group, the IFN-γ and Zol groups showed remarkable attenuation of severe osteoclastogenesis, leading to a significant enhancement in bone mass. Histomorphometric data and mRNA expression patterns in IFN-γ and Zol-injected rats reflected high bone-turnover with increased bone formation, a reduction in osteoclast numbers, and tumor necrosis factor-α expression. Our results demonstrated that the administration of IFN-γ and Zol enhanced bone regeneration of α-TCP/CS implants by enhancing bone formation, while hampering excess bone resorption. PMID:26516841

  3. 21 CFR 880.2740 - Surgical sponge scale.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Surgical sponge scale. 880.2740 Section 880.2740... Devices § 880.2740 Surgical sponge scale. (a) Identification. A surgical sponge scale is a nonelectrically powered device used to weigh surgical sponges that have been used to absorb blood during surgery so that...

  4. [Development of a novel absorbable nanofiber chitosan-collagen membrane by electrospinning and the preliminary study on guided bone regeneration].

    PubMed

    Gao, B; Li, X J; Lin, M; Li, Y Y; Dong, Y

    2018-02-09

    Objective: To evaluate the application effect of nanofiber chitosan-collagen membrane (NCM) on guided bone regeneration (GBR). Methods: The mixture of collagen, chitosan, polyethylene oxide was used to make up the NCM by electrospinning, then the NCM was crosslinked by glutaraldehyde vapor. The physical property of the NCM was measured by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). MC3T3-E1 osteoblasts were cultured on NCM to characterize the biocompatibility. The effectiveness of four groups [contrast group, Bio-gide membrane (BGM), compressed chitosan-collagen menbrane (CCM), NCM/CCM] on bone regeneration were evaluated in critical-sized defects (diameter = 5 mm) in SD rats. Results: When the mixed solution consists of 4.0% collagen, 1.0% chitosan and 3.5% polyethylene oxide, the NCM could be validly fabricated by electrospinning. After cross-linking by glutaraldehyde vapor, the tensile strength and the stability of NCM in damp was enhanced. No cytotoxicity of the NCM was detected on MC3T3-E1 osteoblasts. In vivo study showed that the new bone regeneration ratio of NCM/CCM group was [(43.10±1.49)%], and this was similar to that of the group of BGM [(41.36±2.60)%] ( P> 0.05), but higher than that of the CCM group [(33.10±1.41)%] and the contrast group [(7.22±2.46)%] ( P< 0.05). Conclusions: The NCM can promote new bone regeneration effectively in GBR procedure.

  5. Isolation, Characterization and Evaluation of Collagen from Jellyfish Rhopilema esculentum Kishinouye for Use in Hemostatic Applications.

    PubMed

    Cheng, Xiaochen; Shao, Ziyu; Li, Chengbo; Yu, Lejun; Raja, Mazhar Ali; Liu, Chenguang

    2017-01-01

    Hemostat has been a crucial focus since human body is unable to control massive blood loss, and collagen proves to be an effective hemostat in previous studies. In this study, collagen was isolated from the mesoglea of jellyfish Rhopilema esculentum Kishinouye and its hemostatic property was studied. The yields of acid-soluble collagen (ASC) and pepsin-soluble (PSC) were 0.12% and 0.28% respectively. The SDS-PAGE patterns indicated that the collagen extracted from jellyfish mesoglea was type I collagen. The lyophilized jellyfish collagen sponges were cross-linked with EDC and interconnected networks in the sponges were revealed by scanning electron microscope (SEM). Collagen sponges exhibited higher water absorption rates than medical gauze and EDC/NHS cross-linking method could improve the stability of the collagen sponges. Compared with medical gauze groups, the blood clotting indexes (BCIs) of collagen sponges were significantly decreased (P < 0.05) and the concentration of collagen also had an influence on the hemostatic property (P < 0.05). Collagen sponges had an improved hemostatic ability compared to the gauze control in tail amputation rat models. Hemostatic mechanism studies showed that hemocytes and platelets could adhere and aggregate on the surface of collagen sponge. All properties make jellyfish collagen sponge to be a suitable candidate used as hemostatic material and for wound healing applications.

  6. Isolation, Characterization and Evaluation of Collagen from Jellyfish Rhopilema esculentum Kishinouye for Use in Hemostatic Applications

    PubMed Central

    Cheng, Xiaochen; Liu, Chenguang

    2017-01-01

    Hemostat has been a crucial focus since human body is unable to control massive blood loss, and collagen proves to be an effective hemostat in previous studies. In this study, collagen was isolated from the mesoglea of jellyfish Rhopilema esculentum Kishinouye and its hemostatic property was studied. The yields of acid-soluble collagen (ASC) and pepsin-soluble (PSC) were 0.12% and 0.28% respectively. The SDS-PAGE patterns indicated that the collagen extracted from jellyfish mesoglea was type I collagen. The lyophilized jellyfish collagen sponges were cross-linked with EDC and interconnected networks in the sponges were revealed by scanning electron microscope (SEM). Collagen sponges exhibited higher water absorption rates than medical gauze and EDC/NHS cross-linking method could improve the stability of the collagen sponges. Compared with medical gauze groups, the blood clotting indexes (BCIs) of collagen sponges were significantly decreased (P < 0.05) and the concentration of collagen also had an influence on the hemostatic property (P < 0.05). Collagen sponges had an improved hemostatic ability compared to the gauze control in tail amputation rat models. Hemostatic mechanism studies showed that hemocytes and platelets could adhere and aggregate on the surface of collagen sponge. All properties make jellyfish collagen sponge to be a suitable candidate used as hemostatic material and for wound healing applications. PMID:28103327

  7. Enhanced hyaline cartilage matrix synthesis in collagen sponge scaffolds by using siRNA to stabilize chondrocytes phenotype cultured with bone morphogenetic protein-2 under hypoxia.

    PubMed

    Legendre, Florence; Ollitrault, David; Hervieu, Magalie; Baugé, Catherine; Maneix, Laure; Goux, Didier; Chajra, Hanane; Mallein-Gerin, Frédéric; Boumediene, Karim; Galera, Philippe; Demoor, Magali

    2013-07-01

    Cartilage healing by tissue engineering is an alternative strategy to reconstitute functional tissue after trauma or age-related degeneration. However, chondrocytes, the major player in cartilage homeostasis, do not self-regenerate efficiently and lose their phenotype during osteoarthritis. This process is called dedifferentiation and also occurs during the first expansion step of autologous chondrocyte implantation (ACI). To ensure successful ACI therapy, chondrocytes must be differentiated and capable of synthesizing hyaline cartilage matrix molecules. We therefore developed a safe procedure for redifferentiating human chondrocytes by combining appropriate physicochemical factors: hypoxic conditions, collagen scaffolds, chondrogenic factors (bone morphogenetic protein-2 [BMP-2], and insulin-like growth factor I [IGF-I]) and RNA interference targeting the COL1A1 gene. Redifferentiation of dedifferentiated chondrocytes was evaluated using gene/protein analyses to identify the chondrocyte phenotypic profile. In our conditions, under BMP-2 treatment, redifferentiated and metabolically active chondrocytes synthesized a hyaline-like cartilage matrix characterized by type IIB collagen and aggrecan molecules without any sign of hypertrophy or osteogenesis. In contrast, IGF-I increased both specific and noncharacteristic markers (collagens I and X) of chondrocytes. The specific increase in COL2A1 gene expression observed in the BMP-2 treatment was shown to involve the specific enhancer region of COL2A1 that binds the trans-activators Sox9/L-Sox5/Sox6 and Sp1, which are associated with a decrease in the trans-inhibitors of COL2A1, c-Krox, and p65 subunit of NF-kappaB. Our procedure in which BMP-2 treatment under hypoxia is associated with a COL1A1 siRNA, significantly increased the differentiation index of chondrocytes, and should offer the opportunity to develop new ACI-based therapies in humans.

  8. Hydroxyapatite reinforced collagen scaffolds with improved architecture and mechanical properties.

    PubMed

    Kane, Robert J; Weiss-Bilka, Holly E; Meagher, Matthew J; Liu, Yongxing; Gargac, Joshua A; Niebur, Glen L; Wagner, Diane R; Roeder, Ryan K

    2015-04-01

    Hydroxyapatite (HA) reinforced collagen scaffolds have shown promise for synthetic bone graft substitutes and tissue engineering scaffolds. Freeze-dried HA-collagen scaffolds are readily fabricated and have exhibited osteogenicity in vivo, but are limited by an inherent scaffold architecture that results in a relatively small pore size and weak mechanical properties. In order to overcome these limitations, HA-collagen scaffolds were prepared by compression molding HA reinforcements and paraffin microspheres within a suspension of concentrated collagen fibrils (∼ 180 mg/mL), cross-linking the collagen matrix, and leaching the paraffin porogen. HA-collagen scaffolds exhibited an architecture with high porosity (85-90%), interconnected pores ∼ 300-400 μm in size, and struts ∼ 3-100 μm in thickness containing 0-80 vol% HA whisker or powder reinforcements. HA reinforcement enabled a compressive modulus of up to ∼ 1 MPa, which was an order of magnitude greater than unreinforced collagen scaffolds. The compressive modulus was also at least one order of magnitude greater than comparable freeze-dried HA-collagen scaffolds and two orders of magnitude greater than absorbable collagen sponges used clinically. Moreover, scaffolds reinforced with up to 60 vol% HA exhibited fully recoverable elastic deformation upon loading to 50% compressive strain for at least 100,000 cycles. Thus, the scaffold mechanical properties were well-suited for surgical handling, fixation, and bearing osteogenic loads during bone regeneration. The scaffold architecture, permeability, and composition were shown to be conducive to the infiltration and differentiation of adipose-derive stromal cells in vitro. Acellular scaffolds were demonstrated to induce angiogenesis and osteogenesis after subcutaneous ectopic implantation by recruiting endogenous cell populations, suggesting that the scaffolds were osteoinductive. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights

  9. Vaginal sponge and spermicides

    MedlinePlus

    Birth control - over the counter; Contraceptives - over the counter; Family planning - vaginal sponge; Contraception - vaginal sponge ... preventing pregnancy as some other forms of birth control. However, using a spermicide or sponge is much ...

  10. Evaluation of maxillary alveolar reconstruction using a resorbable collagen sponge with recombinant human bone morphogenetic protein-2 in cleft lip and palate patients.

    PubMed

    Alonso, Nivaldo; Tanikawa, Daniela Yukie Sakai; Freitas, Renato da Silva; Canan, Lady; Ozawa, Terumi Okada; Rocha, Diógenes Laércio

    2010-10-01

    A resorbable collagen matrix with recombinant human bone morphogenetic protein (rhBMP-2) was compared with traditional iliac crest bone graft for the closure of alveolar defects during secondary dental eruption. Sixteen patients with unilateral cleft lip and palate, aged 8 to 12 years, were selected and randomly assigned to group 1 (rhBMP-2) or group 2 (iliac crest bone graft). Computed tomography was performed to assess both groups preoperatively and at months 6 and 12 postoperatively. Bone height and defect volume were calculated through Osirix Dicom Viewer (Pixmeo, Apple Inc.). Overall morbidity was recorded. Preoperative and follow-up examinations revealed progressive alveolar bone union in all patients. For group 1, final completion of the defect with a 65.0% mean bone height was detected 12 months postoperatively. For group 2, final completion of the defect with an 83.8% mean bone height was detected 6 months postoperatively. Dental eruption routinely occurred in both groups. Clinical complications included significant swelling in three group 1 patients (37.5%) and significant donor-site pain in seven group 2 patients (87.5%). For this select group of patients with immature skeleton, rhBMP-2 therapy resulted in satisfactory bone healing and reduced morbidity compared with traditional iliac crest bone grafting.

  11. New composite materials prepared by calcium phosphate precipitation in chitosan/collagen/hyaluronic acid sponge cross-linked by EDC/NHS.

    PubMed

    Kaczmarek, B; Sionkowska, A; Kozlowska, J; Osyczka, A M

    2018-02-01

    Nowadays, fabrication of composite materials based on biopolymers is a rising field due to potential for bone repair and tissue engineering application. Blending of different biopolymers and incorporation of inorganic particles in the blend can lead to new materials with improved physicochemical properties and biocompatibility. In this work 3D porous structures called scaffolds based on chitosan, collagen and hyaluronic acid were obtained through the lyophilization process. Scaffolds were cross-linked by EDC/NHS. Infrared spectra for the materials were made, the percentage of swelling, scaffolds porosity and density, mechanical parameters, thermal stability were studied. Moreover, the scaffolds were used as matrixes for the calcium phosphate in situ precipitation. SEM images were taken and EDX analysis was carried out for calcium and phosphorous content determination in the scaffold. In addition, the adhesion and proliferation of human osteosarcoma SaOS-2 cells was examined on obtained scaffolds. The results showed that the properties of 3D composites cross-linked by EDC/NHS were altered after the addition of 1, 2 and 5% hyaluronic acid. Mechanical parameters, thermal stability and porosity of scaffolds were improved. Moreover, calcium and phosphorous were found in each kind of scaffold. SEM images showed that the precipitation was homogeneously carried in the whole volume of samples. Attachment of SaOS-2 cells to all modified materials was better compared to unmodified control and proliferation of these cells was markedly increased on scaffolds with precipitated calcium phosphate. Obtained materials can provide the support useful in tissue engineering and regenerative medicine. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Cultivation of marine sponges

    NASA Astrophysics Data System (ADS)

    Qu, Yi; Zhang, Wei; Li, Hua; Yu, Xingju; Jin, Meifang

    2005-06-01

    Sponges are the most primitive of multicellular animals, and are major pharmaceutical sources of marine secondary metabolites. A wide variety of new compounds have been isolated from sponges. In order to produce sufficient amounts of the compounds of the needed, it is necessary to obtain large amount of sponges. The production of sponge biomass has become a focus of marine biotechnology.

  13. DYNAPHORE, INC. FORAGER™ SPONGE TECHNOLOGY - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    EPA Science Inventory

    The Forager™ Sponge is an open-celled cellulose sponge incorporating an amine-containing chelating polymer that selectively absorbs dissolved heavy metals from aqueous waste streams. The Developer states that the technology can be utilized to remove and concentrate heavy metals f...

  14. Collagen membranes: a review.

    PubMed

    Bunyaratavej, P; Wang, H L

    2001-02-01

    Collagen materials have been utilized in medicine and dentistry because of their proven biocompatability and capability of promoting wound healing. For guided tissue regeneration (GTR) procedures, collagen membranes have been shown to be comparable to non-absorbable membranes with regard to probing depth reduction, clinical attachment gain, and percent of bone fill. Although these membranes are absorbable, collagen membranes have been demonstrated to prevent epithelial down-growth along the root surfaces during the early phase of wound healing. The use of grafting material in combination with collagen membranes seems to improve clinical outcomes for furcation, but not intrabony, defects when compared to the use of membranes alone. Recently, collagen materials have also been applied in guided bone regeneration (GBR) and root coverage procedures with comparable success rates to non-absorbable expanded polytetrafluoroethylene (ePTFE) membranes and conventional subepithelial connective tissue grafts, respectively. Long-term clinical trials are still needed to further evaluate the benefits of collagen membranes in periodontal and peri-implant defects. This article will review the rationale for each indication and its related literature, both in vitro and in vivo studies. The properties that make collagen membranes attractive for use in regenerative therapy will be addressed. In addition, varieties of cross-linking techniques utilized to retard the degradation rate of collagen membranes will be discussed.

  15. The fibrillar collagen family.

    PubMed

    Exposito, Jean-Yves; Valcourt, Ulrich; Cluzel, Caroline; Lethias, Claire

    2010-01-28

    Collagens, or more precisely collagen-based extracellular matrices, are often considered as a metazoan hallmark. Among the collagens, fibrillar collagens are present from sponges to humans, and are involved in the formation of the well-known striated fibrils. In this review we discuss the different steps in the evolution of this protein family, from the formation of an ancestral fibrillar collagen gene to the formation of different clades. Genomic data from the choanoflagellate (sister group of Metazoa) Monosiga brevicollis, and from diploblast animals, have suggested that the formation of an ancestral alpha chain occurred before the metazoan radiation. Phylogenetic studies have suggested an early emergence of the three clades that were first described in mammals. Hence the duplication events leading to the formation of the A, B and C clades occurred before the eumetazoan radiation. Another important event has been the two rounds of "whole genome duplication" leading to the amplification of fibrillar collagen gene numbers, and the importance of this diversification in developmental processes. We will also discuss some other aspects of fibrillar collagen evolution such as the development of the molecular mechanisms involved in the formation of procollagen molecules and of striated fibrils.

  16. DYNAPHORE, INC., FORAGER SPONGE TECHNOLOGY - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    EPA Science Inventory

    The Forager Sponge is a volume reduction technology in which heavy metal contaminants from an aqueous medium are selectively concentrated into a smaller volume for facilitated disposal. he technology treats contaminated groundwater, surface voters and porous waters by absorbing d...

  17. SITE TECHNOLOGY CAPSULE: DYNAPHORE, INC., FORAGER SPONGE TECHNOLOGY

    EPA Science Inventory

    The Forager Sponge is a volume reduction technology in which heavy metal contaminants from an aqueous medium are selectively concentrated into a smaller volume for facilitated disposal. he technology treats contaminated groundwater, surface waters and porous waters by absorbing d...

  18. Development and testing of a human collagen graft material.

    PubMed

    Quteish, D; Singh, G; Dolby, A E

    1990-06-01

    Human Type I collagen was extracted from placenta using pepsin and salt fractionation. The collagen was characterized by SDS-PAG electrophoresis dispersed in acidic medium, freeze-dried, and cross-linked in an 0.25% glutaraldehyde solution pH 4.5 for 2 days. After washing for 7 days and freeze drying the resultant collagen sponge was tested with regard to mechanical, physical, enzymatic degradation properties and biological responses. The modulus of elasticity was found to be 289 +/- 10 g/mm2 and the sponge was insoluble in water, buffered saline, or tissue culture medium over a period of 6 weeks with swelling occurring at less than 5% of volume. The sponge had a high fluid binding capacity, amounting to 56 +/- 5 mL tissue culture medium per gram of dry weight. Bacterial collagenase produced slow degradation of the sponge with complete disappearance by 24 h only when high concentrations (200 units enzyme per mg of the collagen sponge) were used. Cytotoxicity studies using human gingival and periodontal ligament fibroblasts revealed less than 5% apparent cytotoxicity or proliferation. Subcutaneous implantation was followed by resorption and vascularization over a period of 6-8 weeks. It was concluded that the collagen sponge prepared from human Type I collagen has potential as a graft material in oral surgical procedures.

  19. A polydimethylsiloxane (PDMS) sponge for the selective absorption of oil from water.

    PubMed

    Choi, Sung-Jin; Kwon, Tae-Hong; Im, Hwon; Moon, Dong-Il; Baek, David J; Seol, Myeong-Lok; Duarte, Juan P; Choi, Yang-Kyu

    2011-12-01

    We present a sugar-templated polydimethylsiloxane (PDMS) sponge for the selective absorption of oil from water. The process for fabricating the PDMS sponge does not require any intricate synthesis processes or equipment and it is not environmentally hazardous, thus promoting potential in environmental applications. The proposed PDMS sponge can be elastically deformed into any shape, and it can be compressed repeatedly in air or liquids without collapsing. Therefore, absorbed oils and organic solvents can be readily removed and reused by simply squeezing the PDMS sponge, enabling excellent recyclability. Furthermore, through appropriately combining various sugar particles, the absorption capacity of the PDMS sponge is favorably optimized. © 2011 American Chemical Society

  20. Cultivation of Marine Sponges.

    PubMed

    Osinga; Tramper; Wijffels

    1999-11-01

    There is increasing interest in biotechnological production of marine sponge biomass owing to the discovery of many commercially important secondary metabolites in this group of animals. In this article, different approaches to producing sponge biomass are reviewed, and several factors that possibly influence culture success are evaluated. In situ sponge aquacultures, based on old methods for producing commercial bath sponges, are still the easiest and least expensive way to obtain sponge biomass in bulk. However, success of cultivation with this method strongly depends on the unpredictable and often suboptimal natural environment. Hence, a better-defined production system would be desirable. Some progress has been made with culturing sponges in semicontrolled systems, but these still use unfiltered natural seawater. Cultivation of sponges under completely controlled conditions has remained a problem. When designing an in vitro cultivation method, it is important to determine both qualitatively and quantitatively the nutritional demands of the species that is to be cultured. An adequate supply of food seems to be the key to successful sponge culture. Recently, some progress has been made with sponge cell cultures. The advantage of cell cultures is that they are completely controlled and can easily be manipulated for optimal production of the target metabolites. However, this technique is still in its infancy: a continuous cell line has yet to be established. Axenic cultures of sponge aggregates (primmorphs) may provide an alternative to cell culture. Some sponge metabolites are, in fact, produced by endosymbiotic bacteria or algae that live in the sponge tissue. Only a few of these endosymbionts have been cultivated so far. The biotechnology for the production of sponge metabolites needs further development. Research efforts should be continued to enable commercial exploitation of this valuable natural resource in the near future.

  1. Collagen-Based Biomaterials for Wound Healing

    PubMed Central

    Chattopadhyay, Sayani; Raines, Ronald T.

    2014-01-01

    With its wide distribution in soft and hard connective tissues, collagen is the most abundant of animal proteins. In vitro, natural collagen can be formed into highly organized, three-dimensional scaffolds that are intrinsically biocompatible, biodegradable, non-toxic upon exogenous application, and endowed with high tensile strength. These attributes make collagen the material of choice for wound healing and tissue engineering applications. In this article, we review the structure and molecular interactions of collagen in vivo; the recent use of natural collagen in sponges, injectables, films and membranes, dressings, and skin grafts; and the on-going development of synthetic collagen mimetic peptides as pylons to anchor cytoactive agents in wound beds. PMID:24633807

  2. The role of sponge-bacteria interactions: the sponge Aplysilla rosea challenged by its associated bacterium Streptomyces ACT-52A in a controlled aquarium system.

    PubMed

    Mehbub, Mohammad F; Tanner, Jason E; Barnett, Stephen J; Franco, Christopher M M; Zhang, Wei

    2016-12-01

    Sponge-associated bacteria play a critical role in sponge biology, metabolism and ecology, but how they interact with their host sponges and the role of these interactions are poorly understood. This study investigated the role of the interaction between the sponge Aplysilla rosea and its associated actinobacterium, Streptomyces ACT-52A, in modifying sponge microbial diversity, metabolite profile and bioactivity. A recently developed experimental approach that exposes sponges to bacteria of interest in a controlled aquarium system was improved by including the capture and analysis of secreted metabolites by the addition of an absorbent resin in the seawater. In a series of controlled aquaria, A. rosea was exposed to Streptomyces ACT-52A at 10 6  cfu/ml and monitored for up to 360 h. Shifts in microbial communities associated with the sponges occurred within 24 to 48 h after bacterial exposure and continued until 360 h, as revealed by TRFLP. The metabolite profiles of sponge tissues also changed substantially as the microbial community shifted. Control sponges (without added bacteria) and Streptomyces ACT-52A-exposed sponges released different metabolites into the seawater that was captured by the resin. The antibacterial activity of compounds collected from the seawater increased at 96 and 360 h of exposure for the treated sponges compared to the control group due to new compounds being produced and released. Increased antibacterial activity of metabolites from treated sponge tissue was observed only at 360 h, whereas that of control sponge tissue remained unchanged. The results demonstrate that the interaction between sponges and their associated bacteria plays an important role in regulating secondary metabolite production.

  3. Fabrication and mechanical characterization of a polyvinyl alcohol sponge for tissue engineering applications.

    PubMed

    Karimi, A; Navidbakhsh, M; Faghihi, S

    2014-05-01

    Polyvinyl alcohol (PVA) sponges are widely used for clinical applications, including ophthalmic surgical treatments, wound healing and tissue engineering. There is, however, a lack of sufficient data on the mechanical properties of PVA sponges. In this study, a biomechanical method is used to characterize the elastic modulus, maximum stress and strain as well as the swelling ratio of a fabricated PVA sponge (P-sponge) and it is compared with two commercially available PVA sponges (CENEFOM and EYETEC). The results indicate that the elastic modulus of the P-sponge is 5.32% and 13.45% lower than that of the CENEFOM and EYETEC sponges, while it bears 4.11% more and 10.37% less stress compared to the CENEFOM and EYETEC sponges, respectively. The P-sponge shows a maximum strain of 32% more than the EYETEC sponge as well as a 26.78% higher swelling ratio, which is a significantly higher absorbency compared to the CENEFOM. It is believed that the results of this study would help for a better understanding of the extension, rupture and swelling mechanism of PVA sponges, which could lead to crucial improvement in the design and application of PVA-based materials in ophthalmic and plastic surgeries as well as wound healing and tissue engineering.

  4. The sponge microbiome project.

    PubMed

    Moitinho-Silva, Lucas; Nielsen, Shaun; Amir, Amnon; Gonzalez, Antonio; Ackermann, Gail L; Cerrano, Carlo; Astudillo-Garcia, Carmen; Easson, Cole; Sipkema, Detmer; Liu, Fang; Steinert, Georg; Kotoulas, Giorgos; McCormack, Grace P; Feng, Guofang; Bell, James J; Vicente, Jan; Björk, Johannes R; Montoya, Jose M; Olson, Julie B; Reveillaud, Julie; Steindler, Laura; Pineda, Mari-Carmen; Marra, Maria V; Ilan, Micha; Taylor, Michael W; Polymenakou, Paraskevi; Erwin, Patrick M; Schupp, Peter J; Simister, Rachel L; Knight, Rob; Thacker, Robert W; Costa, Rodrigo; Hill, Russell T; Lopez-Legentil, Susanna; Dailianis, Thanos; Ravasi, Timothy; Hentschel, Ute; Li, Zhiyong; Webster, Nicole S; Thomas, Torsten

    2017-10-01

    Marine sponges (phylum Porifera) are a diverse, phylogenetically deep-branching clade known for forming intimate partnerships with complex communities of microorganisms. To date, 16S rRNA gene sequencing studies have largely utilised different extraction and amplification methodologies to target the microbial communities of a limited number of sponge species, severely limiting comparative analyses of sponge microbial diversity and structure. Here, we provide an extensive and standardised dataset that will facilitate sponge microbiome comparisons across large spatial, temporal, and environmental scales. Samples from marine sponges (n = 3569 specimens), seawater (n = 370), marine sediments (n = 65) and other environments (n = 29) were collected from different locations across the globe. This dataset incorporates at least 268 different sponge species, including several yet unidentified taxa. The V4 region of the 16S rRNA gene was amplified and sequenced from extracted DNA using standardised procedures. Raw sequences (total of 1.1 billion sequences) were processed and clustered with (i) a standard protocol using QIIME closed-reference picking resulting in 39 543 operational taxonomic units (OTU) at 97% sequence identity, (ii) a de novo clustering using Mothur resulting in 518 246 OTUs, and (iii) a new high-resolution Deblur protocol resulting in 83 908 unique bacterial sequences. Abundance tables, representative sequences, taxonomic classifications, and metadata are provided. This dataset represents a comprehensive resource of sponge-associated microbial communities based on 16S rRNA gene sequences that can be used to address overarching hypotheses regarding host-associated prokaryotes, including host specificity, convergent evolution, environmental drivers of microbiome structure, and the sponge-associated rare biosphere. © The Authors 2017. Published by Oxford University Press.

  5. Capillary rise and swelling in cellulose sponges

    NASA Astrophysics Data System (ADS)

    Ha, Jonghyun; Kim, Jungchul; Kim, Ho-Young

    2015-11-01

    A cellulose sponge, which is a mundane example of a porous hydrophilic structure, can absorb and hold a significant amount of liquid. We present the results of experimental and theoretical investigation of the dynamics of the capillary imbibition of various aqueous solutions in the sponge that swells at the same time. We find that the rate of water rise against the resistance caused by gravitational and viscous effects deviates from Washburn's rule beyond a certain threshold height. We rationalize the novel power law of the rise height versus time by combining Darcy's law with hygroscopic swelling equation and also predict the threshold height. The scaling law constructed through this work agrees well with the experimental results, shedding light on the physics of capillary flow in deforming porous media.

  6. Sediment impacts on marine sponges.

    PubMed

    Bell, James J; McGrath, Emily; Biggerstaff, Andrew; Bates, Tracey; Bennett, Holly; Marlow, Joseph; Shaffer, Megan

    2015-05-15

    Changes in sediment input to marine systems can influence benthic environments in many ways. Sponges are important components of benthic ecosystems world-wide and as sessile suspension feeders are likely to be impacted by changes in sediment levels. Despite this, little is known about how sponges respond to changes in settled and suspended sediment. Here we review the known impacts of sedimentation on sponges and their adaptive capabilities, whilst highlighting gaps in our understanding of sediment impacts on sponges. Although the literature clearly shows that sponges are influenced by sediment in a variety of ways, most studies confer that sponges are able to tolerate, and in some cases thrive, in sedimented environments. Critical gaps exist in our understanding of the physiological responses of sponges to sediment, adaptive mechanisms, tolerance limits, and the particularly the effect of sediment on early life history stages. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Investigators unable to substantiate suspected link between sponge, TSS.

    PubMed

    1983-12-01

    contraceptive sponge does not cause TSS: Remarketing trials of the sponge included more than 1000 women years of experience without a reported case of TSS; nonoxynol 9 spermicide and citric, ascorbic, and benzoic acids in the sponge are hostile to S. aureus; unlike tampons, the sponge is not highly absorbant and does not cause microabrasions of the vagina; and during testing, contraceptive sponges were innoculated with the Harrisburg strain of S. aureus known to cause TSS fatality, and after incubation in growth medium for 28 days the S. aureus failed to grow in the innoculated sponges.

  8. The Sponge Hologenome

    PubMed Central

    Thomas, Torsten

    2016-01-01

    ABSTRACT A paradigm shift has recently transformed the field of biological science; molecular advances have revealed how fundamentally important microorganisms are to many aspects of a host’s phenotype and evolution. In the process, an era of “holobiont” research has emerged to investigate the intricate network of interactions between a host and its symbiotic microbial consortia. Marine sponges are early-diverging metazoa known for hosting dense, specific, and often highly diverse microbial communities. Here we synthesize current thoughts about the environmental and evolutionary forces that influence the diversity, specificity, and distribution of microbial symbionts within the sponge holobiont, explore the physiological pathways that contribute to holobiont function, and describe the molecular mechanisms that underpin the establishment and maintenance of these symbiotic partnerships. The collective genomes of the sponge holobiont form the sponge hologenome, and we highlight how the forces that define a sponge’s phenotype in fact act on the genomic interplay between the different components of the holobiont. PMID:27103626

  9. Genetics Home Reference: white sponge nevus

    MedlinePlus

    ... Twitter Home Health Conditions White sponge nevus White sponge nevus Printable PDF Open All Close All Enable ... to view the expand/collapse boxes. Description White sponge nevus is a condition characterized by the formation ...

  10. Freeze-dried, cross-linked bovine type I collagen: analysis of properties.

    PubMed

    Hyder, P R; Dowell, P; Singh, G; Dolby, A E

    1992-03-01

    This study was undertaken to assess the physical and biological properties of freeze-dried cross-linked bovine type I collagen and to assess its potential for use in the guided tissue regeneration method of treatment of periodontal disease in human adult subjects. The modulus of elasticity, swelling ratio, and biodegradation rate were investigated. The collagen sponge was implanted subdermally into Sprague-Dawley rats and a histological study carried out at 2, 7, 21, 35, and 49 days post implantation. Growth of human gingival and periodontal ligament derived fibroblasts on collagen sponge was assessed, as well as the effect of bovine collagen supernatants upon gingival and periodontal fibroblast cultures. The physical properties of the collagen sponge were consistent with good handling qualities and, therefore, it was appropriate for use at a surgical site. The histological study demonstrated a reduction in thickness of the collagen at 21 days; at 35 days there was a hazy appearance of the collagen remnants; and at 49 days the graft material had been completely replaced with fibrous tissues. The in vitro response of human gingival and periodontal fibroblasts to bovine collagen showed that, after 21 days, confluent fibroblast growth was observed around and underneath the sponge. The effect of bovine collagen supernatants upon fibroblasts demonstrated an apparent proliferative effect of the supernatant with both gingival and periodontal ligament fibroblasts. However, the non-parametric Friedman test revealed no significant differences between dilutions or time points. The overall findings provide encouraging evidence of the safety of freeze-dried cross-linked bovine collagen sponge in the surgical treatment of periodontal disease.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. The use of haemostatic gelatin sponges in veterinary surgery.

    PubMed

    Charlesworth, T M; Agthe, P; Moores, A; Anderson, D M

    2012-01-01

    To describe the use of absorbable gelatin sponges as haemostatic implants in clinical veterinary surgical cases and to document any related postoperative complications. Practice databases were searched for the product names "Gelfoam" and "Spongostan". Patient records were retrieved and data regarding patient signalment, surgical procedure, National Resource Council (NRC) wound classification, source of haemorrhage, pre- and postoperative body temperature, postoperative complications, time to discharge and details of any postoperative imaging were recorded and reviewed. Follow-up information was obtained by repeat clinical examination or telephone interview with either the owner or referring veterinary surgeon. Cases with incomplete surgical records or those which were not recovered from anaesthesia were excluded from the analysis. Fifty cases (44 dogs and 6 cats) satisfied the inclusion criteria. Satisfactory haemostasis was achieved in 49 cases with one case requiring reoperation during which a second gelatin sponge was used. There were no detected hypersensitivity responses or confirmed postoperative complications relating to the use of gelatin sponges during the follow-up period (median 13 months). This is the first review of the use of gelatin sponges in clinical veterinary surgery and suggests that gelatin sponges are safe to use in cats and dogs. © 2011 British Small Animal Veterinary Association.

  12. Polymer/reduced graphene oxide functionalized sponges as superabsorbents for oil removal and recovery.

    PubMed

    Periasamy, Arun Prakash; Wu, Wen-Ping; Ravindranath, Rini; Roy, Prathik; Lin, Guan-Lin; Chang, Huan-Tsung

    2017-01-30

    Polyurethane dish-washing (PU-DW) sponges are functionalized sequentially with polyethylenimine (PEI) and graphene oxide (GO) to form PEI/reduced graphene oxide (RGO) PU-DW sponges. The PEI/RGO PU-DW sponge consists of PEI/RGO sheets having numerous pores, with diameters ranging from 236 to 254nm. To further enhance hydrophobicity and absorption capacity of oil, PEI/RGO PU-DW sponge is further coated with 20% phenyltrimethoxysilane (PTMOS). The PTMOS/PEI/RGO PU-DW sponge absorbs various oils within 20s, with maximum absorption capacity values of 880% and 840% for bicycle chain oil and motorcycle engine oil, respectively. The absorbed oils were released completely by squeezing or immersed in hexane. The PTMOS/PEI/RGO PU-DW sponge efficiently separates oil/water mixtures through a flowing system. Having the advantages of faster absorption rate, reusability, and low cost, the PTMOS/PEI/RGO PU-DW sponge holds great potential as a superabsorbent for efficient removal and recovery of oil spills as well as for the separation of oil/water mixtures. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Poro-elasto-capillary wicking of cellulose sponges

    PubMed Central

    Kim, Do-Nyun

    2018-01-01

    We mundanely observe cellulose (kitchen) sponges swell while absorbing water. Fluid flows in deformable porous media, such as soils and hydrogels, are classically described on the basis of the theories of Darcy and poroelasticity, where the expansion of media arises due to increased pore pressure. However, the situation is qualitatively different in cellulosic porous materials like sponges because the pore expansion is driven by wetting of the surrounding cellulose walls rather than by increase of the internal pore pressure. We address a seemingly so simple but hitherto unanswered question of how fast water wicks into the swelling sponge. Our experiments uncover a power law of the wicking height versus time distinct from that for nonswelling materials. The observation using environmental scanning electron microscopy reveals the coalescence of microscale wall pores with wetting, which allows us to build a mathematical model for pore size evolution and the consequent wicking dynamics. Our study sheds light on the physics of water absorption in hygroscopically responsive multiscale porous materials, which have far more implications than everyday activities (for example, cleaning, writing, and painting) carried out with cellulosic materials (paper and sponge), including absorbent hygiene products, biomedical cell cultures, building safety, and cooking. PMID:29682606

  14. Human Recombinant Peptide Sponge Enables Novel, Less Invasive Cell Therapy for Ischemic Stroke

    PubMed Central

    Miyamoto, Michiyuki; Yamauchi, Tomohiro; Kawabori, Masahito; Osanai, Toshiya; Sasaki, Tasuku; Houkin, Kiyohiro; Kuroda, Satoshi

    2018-01-01

    Bone marrow stromal cell (BMSC) transplantation has the therapeutic potential for ischemic stroke. However, it is unclear which delivery routes would yield both safety and maximal therapeutic benefits. We assessed whether a novel recombinant peptide (RCP) sponge, that resembles human collagen, could act as a less invasive and beneficial scaffold in cell therapy for ischemic stroke. BMSCs from green fluorescent protein-transgenic rats were cultured and Sprague–Dawley rats were subjected to permanent middle cerebral artery occlusion (MCAo). A BMSC-RCP sponge construct was transplanted onto the ipsilateral intact neocortex 7 days after MCAo. A BMSC suspension or vehicle was transplanted into the ipsilateral striatum. Rat motor function was serially evaluated and histological analysis was performed 5 weeks after transplantation. The results showed that BMSCs could proliferate well in the RCP sponge and the BMSC-RCP sponge significantly promoted functional recovery, compared with the vehicle group. Histological analysis revealed that the RCP sponge provoked few inflammatory reactions in the host brain. Moreover, some BMSCs migrated to the peri-infarct area and differentiated into neurons in the BMSC-RCP sponge group. These findings suggest that the RCP sponge may be a promising candidate for animal protein-free scaffolds in cell therapy for ischemic stroke in humans. PMID:29765415

  15. Human Recombinant Peptide Sponge Enables Novel, Less Invasive Cell Therapy for Ischemic Stroke.

    PubMed

    Miyamoto, Michiyuki; Nakamura, Kentaro; Shichinohe, Hideo; Yamauchi, Tomohiro; Ito, Masaki; Saito, Hisayasu; Kawabori, Masahito; Osanai, Toshiya; Sasaki, Tasuku; Houkin, Kiyohiro; Kuroda, Satoshi

    2018-01-01

    Bone marrow stromal cell (BMSC) transplantation has the therapeutic potential for ischemic stroke. However, it is unclear which delivery routes would yield both safety and maximal therapeutic benefits. We assessed whether a novel recombinant peptide (RCP) sponge, that resembles human collagen, could act as a less invasive and beneficial scaffold in cell therapy for ischemic stroke. BMSCs from green fluorescent protein-transgenic rats were cultured and Sprague-Dawley rats were subjected to permanent middle cerebral artery occlusion (MCAo). A BMSC-RCP sponge construct was transplanted onto the ipsilateral intact neocortex 7 days after MCAo. A BMSC suspension or vehicle was transplanted into the ipsilateral striatum. Rat motor function was serially evaluated and histological analysis was performed 5 weeks after transplantation. The results showed that BMSCs could proliferate well in the RCP sponge and the BMSC-RCP sponge significantly promoted functional recovery, compared with the vehicle group. Histological analysis revealed that the RCP sponge provoked few inflammatory reactions in the host brain. Moreover, some BMSCs migrated to the peri-infarct area and differentiated into neurons in the BMSC-RCP sponge group. These findings suggest that the RCP sponge may be a promising candidate for animal protein-free scaffolds in cell therapy for ischemic stroke in humans.

  16. Morphological responses of dissociated sponge cells to different organic substrata.

    PubMed

    Gaino, E; Magnino, G; Burlando, B; Sara', M

    1993-06-01

    To study interactions between sponge cells and components of the extracellular matrix (ECM), cells of the calcareous sponge Clathrina cerebrum were investigated in vitro by scanning electron microscopy. Cells were settled on glass coverslips, used as controls, and on coverslips coated with various ECM components (laminin, collagens and fibronectin), and with an adhesive substance (polylysine). Cells tended to conserve a rounded shape, producing thin, stiff processes (scleropodia) and lamellipodia, whose shape and extension varied according to the substrata. Spreading was observed only on polylysine, inducing cells to assume a fibroblast-like aspect. On laminin, cell adhesion was assured only by scleropodia. On fibronectin, scleropodia and lamellipodia were present, but reduced in size and length. On collagens, laminar processes occurred among prevailing scleropodia. Measurements of cell area and perimeter allowed statistical comparison of substrata, on the basis of their induction of cell flattening and protuberance formation. In summary, sponge cells were found to modulate their morphology in response to the external environment, expressing features for dynamic activities most fully in the presence of substances close to their natural ECM constituents. These results are discussed in the context of tissue rearrangement as a basic adaptation occurring throughout the life span of these organisms.

  17. Collagenous gastritis.

    PubMed

    Jin, Xiaoyi; Koike, Tomoyuki; Chiba, Takashi; Kondo, Yutaka; Ara, Nobuyuki; Uno, Kaname; Asano, Naoki; Iijima, Katsunori; Imatani, Akira; Watanabe, Mika; Shirane, Akio; Shimosegawa, Tooru

    2013-09-01

    In the present paper, we report a case of rare collagenous gastritis. The patient was a 25-year-old man who had experienced nausea, abdominal distention and epigastralgia since 2005. Esophagogastroduodenoscopy (EGD) carried out at initial examination by the patient's local doctor revealed an extensively discolored depression from the upper gastric body to the lower gastric body, mainly including the greater curvature, accompanied by residual mucosa with multiple islands and nodularity with a cobblestone appearance. Initial biopsies sampled from the nodules and accompanying atrophic mucosa were diagnosed as chronic gastritis. In August, 2011, the patient was referred to Tohoku University Hospital for observation and treatment. EGD at our hospital showed the same findings as those by the patient's local doctor. Pathological findings included a membranous collagen band in the superficial layer area of the gastric mucosa, which led to a diagnosis of collagenous gastritis. Collagenous gastritis is an extremely rare disease, but it is important to recognize its characteristic endoscopic findings to make a diagnosis. © 2012 The Authors. Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society.

  18. An experimental-finite element analysis on the kinetic energy absorption capacity of polyvinyl alcohol sponge.

    PubMed

    Karimi, Alireza; Navidbakhsh, Mahdi; Razaghi, Reza

    2014-06-01

    Polyvinyl alcohol (PVA) sponge is in widespread use for biomedical and tissue engineering applications owing to its biocompatibility, availability, relative cheapness, and excellent mechanical properties. This study reports a novel concept of design in energy absorbing materials which consist in the use of PVA sponge as an alternative reinforcement material to enhance the energy loss of impact loads. An experimental study is carried out to measure the mechanical properties of the PVA sponge under uniaxial loading. The kinetic energy absorption capacity of the PVA sponge is computed by a hexahedral finite element (FE) model of the steel ball and bullet through the LS-DYNA code under impact load at three different thicknesses (5, 10, 15mm). The results show that a higher sponge thickness invokes a higher energy loss of the steel ball and bullet. The highest energy loss of the steel ball and bullet is observed for the thickest sponge with 160 and 35J, respectively. The most common type of traumatic brain injury in which the head subject to impact load causes the brain to move within the skull and consequently brain hemorrhaging. These results suggest the application of the PVA sponge as a great kinetic energy absorber material compared to commonly used expanded polystyrene foams (EPS) to absorb most of the impact energy and reduces the transmitted load. The results might have implications not only for understanding of the mechanical properties of PVA sponge but also for use as an alternative reinforcement material in helmet and packaging material design. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Fabrication of polysiloxane-modified polyurethane sponge as low-cost organics/water separation and selective absorption material.

    PubMed

    Cui, Zhengshan; He, Wanxia; Liu, Jun; Wei, Wei; Jiang, Liang; Huang, Jun; Lv, Xiaomeng

    2016-10-01

    Through sol-gel and dip-coating processes, commercial polyurethane sponge modified by polysiloxane was fabricated under low temperature (60 °C) and atmosphere. The contact angle of the obtained polysiloxane/polyurethane sponge is 145 ± 5°. Hence, the polysiloxane/polyurethane sponge could float on water and selectively absorb organics from the surface of the water, indicating simultaneous properties of hydrophobicity and oleophilicity. The absorbent maximum value is 50-150 times of its own weight. The polysiloxane/polyurethane sponge exhibited excellent recyclability, which could be reused by squeezing the sponge due to its high mechanical stability and flexibility. Thermogravimetry-differential thermal analysis test indicated that the polysiloxane/polyurethane sponge exhibited good thermal stability and the stable contact angle of samples tested under increasing temperature indicated its good weather resistance. Due to the commercial property of polyurethane sponge and easy-handling of polysiloxane, the polysiloxane/polyurethane sponge can be easily scaled up to recover a large-area oil spill in water and further work based on the designed equipment has been under consideration.

  20. Sponge systematics facing new challenges.

    PubMed

    Cárdenas, P; Pérez, T; Boury-Esnault, N

    2012-01-01

    Systematics is nowadays facing new challenges with the introduction of new concepts and new techniques. Compared to most other phyla, phylogenetic relationships among sponges are still largely unresolved. In the past 10 years, the classical taxonomy has been completely overturned and a review of the state of the art appears necessary. The field of taxonomy remains a prominent discipline of sponge research and studies related to sponge systematics were in greater number in the Eighth World Sponge Conference (Girona, Spain, September 2010) than in any previous world sponge conferences. To understand the state of this rapidly growing field, this chapter proposes to review studies, mainly from the past decade, in sponge taxonomy, nomenclature and phylogeny. In a first part, we analyse the reasons of the current success of this field. In a second part, we establish the current sponge systematics theoretical framework, with the use of (1) cladistics, (2) different codes of nomenclature (PhyloCode vs. Linnaean system) and (3) integrative taxonomy. Sponges are infamous for their lack of characters. However, by listing and discussing in a third part all characters available to taxonomists, we show how diverse characters are and that new ones are being used and tested, while old ones should be revisited. We then review the systematics of the four main classes of sponges (Hexactinellida, Calcispongiae, Homoscleromorpha and Demospongiae), each time focusing on current issues and case studies. We present a review of the taxonomic changes since the publication of the Systema Porifera (2002), and point to problems a sponge taxonomist is still faced with nowadays. To conclude, we make a series of proposals for the future of sponge systematics. In the light of recent studies, we establish a series of taxonomic changes that the sponge community may be ready to accept. We also propose a series of sponge new names and definitions following the PhyloCode. The issue of phantom species

  1. A Sulfilimine Bond Identified in Collagen IV

    PubMed Central

    Vanacore, Roberto; Ham, Amy-Joan L.; Voehler, Markus; Sanders, Charles R.; Conrads, Thomas P.; Veenstra, Timothy D.; Sharpless, K. Barry; Dawson, Philip E.; Hudson, Billy G.

    2010-01-01

    Collagen IV networks are ancient proteins of basement membranes that underlie epithelia in metazoa from sponge to human. The networks provide structural integrity to tissues and serve as ligands for integrin cell-surface receptors. They are assembled by oligomerization of triple-helical protomers and are covalently cross-linked, a key reinforcement that stabilizes networks. We used Fourier-transform ion cyclotron resonance mass spectrometry and nuclear magnetic resonance spectroscopy to show that a sulfilimine bond (-S=N-) crosslinks hydroxylysine-211 and methionine-93 of adjoining protomers, a bond not previously found in biomolecules. This bond, the nitrogen analog of a sulfoxide, appears to have arisen at the divergence of sponge and cnidaria, an adaptation of the extracellular matrix in response to mechanical stress in metazoan evolution. PMID:19729652

  2. Functionalized three-dimensional graphene sponges for highly efficient crude and diesel oil adsorption.

    PubMed

    Bagoole, Oscar; Rahman, Md Mahfuzur; Shah, Sohail; Hong, Haiping; Chen, Hang; Al Ghaferi, Amal; Younes, Hammad

    2018-06-02

    Modified Hummer's method has been used in this study to synthesize graphene oxide (GO) solution that was utilized for the fabrication of three-dimensional (3D) graphene sponges and their subsequent functionalization through a low-cost and facile vapor-based surface enhancement approach. The functionalized 3D-graphene sponge is an excellent absorbent, which can remove more than 3300 wt.% of crude oil (calculated with respect to the original sorbent mass). The functionalization of the obtained graphene sponges with trichloro (1H,1H,2H,2H-perfluorooctyl)silane enhanced their wettability properties due to the super-hydrophobic nature of the resulting materials characterized by the contact angles in water greater than 150°. Furthermore, their elastic compression modulus (estimated by conducting a series of compression tests) was about 22.3 kPa. The equilibrium modeling of the oil removal process, which was performed by plotting Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich isotherms, confirmed the properties of the fabricated 3D graphene sponges as exceptional absorbents for crude and diesel oil, which could be attributed to the oleophilic nature of graphene. Moreover, the obtained 3D graphene sponges could be regenerated via heat treatment, which was conducted to release the adsorbed species. After five adsorption-desorption cycles, the sorption capacity of the produced 3D graphene sponges towards crude oil reached 95% of the initial value.

  3. Insights into early extracellular matrix evolution: spongin short chain collagen-related proteins are homologous to basement membrane type IV collagens and form a novel family widely distributed in invertebrates.

    PubMed

    Aouacheria, Abdel; Geourjon, Christophe; Aghajari, Nushin; Navratil, Vincent; Deléage, Gilbert; Lethias, Claire; Exposito, Jean-Yves

    2006-12-01

    Collagens are thought to represent one of the most important molecular innovations in the metazoan line. Basement membrane type IV collagen is present in all Eumetazoa and was found in Homoscleromorpha, a sponge group with a well-organized epithelium, which may represent the first stage of tissue differentiation during animal evolution. In contrast, spongin seems to be a demosponge-specific collagenous protein, which can totally substitute an inorganic skeleton, such as in the well-known bath sponge. In the freshwater sponge Ephydatia mülleri, we previously characterized a family of short-chain collagens that are likely to be main components of spongins. Using a combination of sequence- and structure-based methods, we present evidence of remote homology between the carboxyl-terminal noncollagenous NC1 domain of spongin short-chain collagens and type IV collagen. Unexpectedly, spongin short-chain collagen-related proteins were retrieved in nonsponge animals, suggesting that a family related to spongin constitutes an evolutionary sister to the type IV collagen family. Formation of the ancestral NC1 domain and divergence of the spongin short-chain collagen-related and type IV collagen families may have occurred before the parazoan-eumetazoan split, the earliest divergence among extant animal phyla. Molecular phylogenetics based on NC1 domain sequences suggest distinct evolutionary histories for spongin short-chain collagen-related and type IV collagen families that include spongin short-chain collagen-related gene loss in the ancestors of Ecdyzosoa and of vertebrates. The fact that a majority of invertebrates encodes spongin short-chain collagen-related proteins raises the important question to the possible function of its members. Considering the importance of collagens for animal structure and substratum attachment, both families may have played crucial roles in animal diversification.

  4. Development of biomimetic tilapia collagen nanofibers for skin regeneration through inducing keratinocytes differentiation and collagen synthesis of dermal fibroblasts.

    PubMed

    Zhou, Tian; Wang, Nanping; Xue, Yang; Ding, Tingting; Liu, Xin; Mo, Xiumei; Sun, Jiao

    2015-02-11

    In this study, tilapia skin collagen sponge and electrospun nanofibers were developed for wound dressing. The collagen sponge was composed of at least two α-peptides, and its denaturation temperature was 44.99 °C. It did not change the number of spleen-derived lymphocytes in BALB/c mice, the ratio of CD4+/CD8+ lymphocytes, and the level of IgG or IgM in Sprague-Dawley rat. The contact angle, tensile strength, and weight loss temperature of collagen nanofibers were 21.2°, 6.72±0.44 MPa, and 300 °C, respectively. The nanofibers could promote the viabilities of human keratinocytes (HaCaTs) and human dermal fibroblasts (HDFs), inducing epidermal differentiation through the gene expression of involucrin, filaggrin, and type I transglutaminase of HaCaTs, and they could also accelerate migration of HaCaTs with the expression of matrix metalloproteinase-9 and transforming growth factor-β1 (TGF-β1). Besides, the nanofibers could upregulate the protien level of Col-I in HDFs both via a direct effect and TGF-β1 secreted from HaCaTs, thus facilitating the formation of collagen fibers. Furthermore, the collagen nanofibers stimulated the skin regeneration rapidly and effectively in vivo. These biological effects could be explained as the contributions from the biomimic extracellular cell matrix structure, hydrophilicity, and the multiple amino acids of the collagen nanofibers.

  5. Is the universe a sponge?

    NASA Astrophysics Data System (ADS)

    Bucher, Martin

    2016-11-01

    Does the large-scale universe look more like meatballs, like Swiss cheese or like a sponge? The differences between these types of universe are described in J Richard Gott's The Cosmic Web: Mysterious Architecture of the Universe.

  6. An analysis of sponge genomes.

    PubMed

    Costantini, Maria

    2004-11-24

    The genome of sponges has only been investigated so far by Bartmann-Lindholm et al. [Progr. Colloid. Polym. Sci. 107 (1997) 122-126] who reported a multimodal CsCl profile which could be resolved into five peaks for Geodia cydonium. This problem was reinvestigated here on both G. cydonium and Suberites domuncula. It was shown that DNAs from both sponges are characterized by unimodal CsCl profiles, additional peaks being due to contaminating prokaryotic and eukaryotic microorganisms.

  7. Sound Absorbers

    NASA Astrophysics Data System (ADS)

    Fuchs, H. V.; Möser, M.

    Sound absorption indicates the transformation of sound energy into heat. It is, for instance, employed to design the acoustics in rooms. The noise emitted by machinery and plants shall be reduced before arriving at a workplace; auditoria such as lecture rooms or concert halls require a certain reverberation time. Such design goals are realised by installing absorbing components at the walls with well-defined absorption characteristics, which are adjusted for corresponding demands. Sound absorbers also play an important role in acoustic capsules, ducts and screens to avoid sound immission from noise intensive environments into the neighbourhood.

  8. Heat Sponge: A Concept for Mass-Efficient Heat Storage

    NASA Technical Reports Server (NTRS)

    Splinter, Scott C.; Blosser, Max L.; Gifford, Andrew R.

    2008-01-01

    The heat sponge is a device for mass-efficient storage of heat. It was developed to be incorporated in the substructure of a re-entry vehicle to reduce thermal- protection-system requirements. The heat sponge consists of a liquid/vapor mixture contained within a number of miniature pressure vessels that can be embedded within a variety of different types of structures. As temperature is increased, pressure in the miniature pressure vessels also increases so that heat absorbed through vaporization of the liquid is spread over a relatively large temperature range. Using water as a working fluid, the heat-storage capacity of the liquid/vapor mixture is many times higher than that of typical structural materials and is well above that of common phase change materials over a temperature range of 200 F to 700 F. The use of pure ammonia as the working fluid provides a range of application between 432 deg R and 730 deg R, or the use of the more practical water-ammonia solution provides a range of application between 432 deg R and 1160 deg R or in between that of water and pure ammonia. Prototype heat sponges were fabricated and characterized. These heat sponges consisted of 1.0-inch-diameter, hollow, stainless-steel spheres with a wall thickness of 0.020 inches which had varying percentages of their interior volumes filled with water and a water-ammonia solution. An apparatus to measure the heat stored in these prototype heat sponges was designed, fabricated, and verified. The heat-storage capacity calculated from measured temperature histories is compared to numerical predictions.

  9. Tear fluid collection in dogs and cats using ophthalmic sponges.

    PubMed

    Sebbag, Lionel; Harrington, Danielle M; Mochel, Jonathan P

    2018-05-01

    To compare the use of two ophthalmic sponges for tear collection in dogs and cats. Ten healthy dogs and 10 healthy cats. A strip (4 × 10 mm) of either cellulose or polyvinyl acetal (PVA) sponge was inserted into the ventral fornix of each eye for either 15, 30, or 60 s. The wetted strip was placed into a 0.2-mL tube that was first punctured at its bottom. Tears were eluted through the drainage hole into a 1.5-mL tube via centrifugation. Tear volume absorbed (VA) and tear volume recovered (VR) were calculated as the difference of the post- and precollection weight of the 0.2-mL tube and 1.5-mL tube, respectively. Recovery ratio (RR) was determined as the ratio between VR and VA. Ophthalmic sponges were well tolerated by all subjects. In dogs and cats, median (95% range) VA, VR, and RR were as follows: 44 μL (11-106 μL) and 16 μL (2-43 μL); 27 μL (1-84 μL) and 6 μL (0-29 μL); 64% (7-91%) and 35% (0-86%), respectively. PVA sponges achieved significantly greater VR in cats and RR in both species. All parameters were significantly greater with a collection time of 60 vs. 30 and 15 s. Body weight was associated with VA and VR in dogs but not cats. Polyvinyl acetal is better than cellulose for tear collection given its superior recovery. Ophthalmic sponges could facilitate routine analysis of tear fluid in dogs and cats, although further studies are needed to evaluate the quality of tears obtained with this method. © 2017 American College of Veterinary Ophthalmologists.

  10. Martian 'Kitchen Sponge'

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This picture is illuminated by sunlight from the upper left. It shows a tiny 1 kilometer by 1 kilometer (0.62 x 0.62 mile) area of the martian north polar residual ice cap as it appears in summertime.

    The surface looks somewhat like that of a kitchen sponge--it is flat on top and has many closely-spaced pits of no more than 2 meters (5.5 ft) depth. The upper, flat surface in this image has a medium-gray tone, while the pit interiors are darker gray. Each pit is generally 10 to 20 meters (33-66 feet) across. The pits probably form as water ice sublimes--going directly from solid to vapor--during the martian northern summer seasons. The pits probably develop over thousands of years. This texture is very different from what is seen in the south polar cap, where considerably larger and more circular depressions are found to resemble slices of swiss cheese rather than a kitchen sponge.

    This picture was taken by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) during northern summer on March 8, 1999. It was one of the very last 'calibration' images taken before the start of the Mapping Phase of the MGS mission, and its goal was to determine whether the MOC was properly focused. The crisp appearance of the edges of the pits confirmed that the instrument was focused and ready for its 1-Mars Year mapping mission. The scene is located near 86.9oN, 207.5oW, and has a resolution of about 1.4 meters (4 ft, 7 in) per pixel.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  11. [Morphology of collagen matrices for tissue engineering (biocompatibility, biodegradation, tissue response)].

    PubMed

    Shekhter, A B; Guller, A E; Istranov, L P; Istranova, E V; Butnaru, D V; Vinarov, A Z; Zakharkina, O L; Kurkov, A V; Kantimerov, D F; Antonov, E N; Marisov, L V; Glybochko, P V

    2015-01-01

    to perform a comparative morphological study of biocompatibility, biodegradation, and tissue response to implantation of collagen matrices (scaffolds) for tissue engineering in urology and other areas of medicine. Nine matrix types, such as porous materials reconstructed from collagen solution; a collagen sponge-vicryl mesh composite; decellularized and freeze-dried bovine, equine, and fish dermis; small intestinal submucosa, decellularized bovine dura mater; and decellularized human femoral artery, were implanted subcutaneously in 225 rats. The tissues at the implantation site were investigated for a period of 5 to 90 days. Classical histology and nonlinear optical microscopy (NLOM) were applied. The investigations showed no rejection of all the collagen materials. The period of matrix bioresorption varied from 10 days for collagen sponges to 2 months for decellularized and freeze-dried vessels and vicryl meshes. Collagen was prone to macrophage resorption and enzymatic lysis, being replaced by granulation tissue and then fibrous tissue, followed by its involution. NLOM allowed the investigators to study the number, density, interposition, and spatial organization of collagen structures in the matrices and adjacent tissues, and their change over time during implantation. The performed investigation could recommend three matrices: hybrid collagen/vicryl composite; decellularized bovine dermis; and decellularized porcine small intestinal submucosa, which are most adequate for tissue engineering in urology. These and other collagen matrices may be used in different areas of regenerative medicine.

  12. DEMONSTRATION BULLETIN: FORAGER™ SPONGE TECHNOLOGY - DYNAPHORE, INC.

    EPA Science Inventory

    The Forager™ Sponge is an open-celled cellulose sponge incorporating an amine-containing chelating polymer that has selective affinity for dissolved heavy metals in both cationic and anionic states. The Forager™ Sponge technology can be utilized to remove and concentrate heavy me...

  13. Hydroxyapatite/collagen bone-like nanocomposite.

    PubMed

    Kikuchi, Masanori

    2013-01-01

    Our group has succeeded to synthesize material with bone-like nanostructure and bone-like inorganic and organic composition via self-organization mechanism between them using simultaneous titration method under controlled pH and temperature. The hydroxyapatite/collagen (HAp/Col) bone-like nanocomposite completely incorporated into bone remodeling process to be substituted by new bone. Cells cultured on the HAp/Col revealed very interesting reactions. Osteoblast-like MG63 cells showed upregulation of alkaline phosphatase >3 times greater than MG63 cells cultured on tissue culture polystyrene (TCPS). MG63 cells 3-dimensionally cultured in a "HAp/Col sponge," a porous HAp/Col having sponge-like viscoelasticity, accumulated calcium phosphate nodules on extracellular matrices they secreted. Bone marrow cells co-cultured with osteoblasts on HAp/Col differentiated to osteoclasts without differentiation supplements. This phenomenon is not found in cells cultured on hydroxyapatite ceramics and TCPS, and rarely in cells cultured on dentin. These results suggest that HAp/Col is a good candidate for tissue engineering of bone as well as bone filler. In a clinical test as a bone filler, the HAp/Col sponge was significantly better than porous β-tricalcium phosphate. The HAp/Col sponge has been approved by the Japanese government and will be used as greatly needed bone filler in patients. In addition to the above, HAp/Col coating on titanium revealed higher osteo-conductivity than HAp-coated titanium and bare titanium and improved direct bonding between titanium and newly formed bone. The HAp/Col coating may be used for metal devices requiring osseointegration.

  14. In vitro and in vivo evaluation of the marine sponge skeleton as a bone mimicking biomaterial.

    PubMed

    Nandi, Samit K; Kundu, Biswanath; Mahato, Arnab; Thakur, Narsinh L; Joardar, Siddhartha N; Mandal, Biman B

    2015-02-01

    This investigation was carried out to identify and characterize marine sponges as potential bioscaffolds in bone tissue engineering. The marine sponge (Biemna fortis) samples were collected from the rocky intertidal region of Anjuna, Goa, India, freeze-dried and converted to pure cristobalite at low temperature. After thorough evaluation of sponge samples by DTA-TGA thermography, XRD, FTIR, SEM and cell cytotoxicity by MTT assay, bare sponge scaffolds were fabricated by firing at 1190 °C. These scaffolds were loaded with growth factors (IGF-1 and BMP-2), checked for quasi-dynamic in vitro release kinetics and finally implanted into femoral bone defects in rabbits for up to 90 days, by keeping an empty defect as a control. The in vivo bone healing process was evaluated and compared using chronological radiology, histology, SEM and fluorochrome labeling studies. SEM revealed that the sponge skeleton possesses a collagenous fibrous network consisting of highly internetworked porosity in the size range of 10-220 μm. XRD and FTIR analysis showed a cristobalite phase with acicular crystals of high aspect ratio, and crystallinity was found to increase from 725 to 1190 °C. MTT assay demonstrated the non-cytotoxicity of the samples. A combination of burst and sustained release profile was noticed for both the growth factors and about 74.3% and 83% total release at day 28. In the radiological, histological, scanning electron microscopy and fluorochrome labeling analysis, the IGF-1 impregnated converted sponge scaffold promoted excellent osseous tissue formation followed by the BMP-2 loaded and bare one. These observations suggest that the marine sponge alone and in combination with growth factors is a promising biomaterial for bone repair and bone augmentation.

  15. Collagen structure of tendon relates to function.

    PubMed

    Franchi, Marco; Trirè, Alessandra; Quaranta, Marilisa; Orsini, Ester; Ottani, Victoria

    2007-03-30

    A tendon is a tough band of fibrous connective tissue that connects muscle to bone, designed to transmit forces and withstand tension during muscle contraction. Tendon may be surrounded by different structures: 1) fibrous sheaths or retinaculae; 2) reflection pulleys; 3) synovial sheaths; 4) peritendon sheaths; 5) tendon bursae. Tendons contain a) few cells, mostly represented by tenoblasts along with endothelial cells and some chondrocytes; b) proteoglycans (PGs), mainly decorin and hyaluronan, and c) collagen, mostly type I. Tendon is a good example of a high ordered extracellular matrix in which collagen molecules assemble into filamentous collagen fibrils (formed by microfibrils) which aggregate to form collagen fibers, the main structural components. It represents a multihierarchical structure as it contains collagen molecules arranged in fibrils then grouped in fibril bundles, fascicles and fiber bundles that are almost parallel to the long axis of the tendon, named as primary, secondary and tertiary bundles. Collagen fibrils in tendons show prevalently large diameter, a D-period of about 67 nm and appear built of collagen molecules lying at a slight angle (< 5 degrees). Under polarized light microscopy the collagen fiber bundles appear crimped with alternative dark and light transverse bands. In recent studies tendon crimps observed via SEM and TEM show that the single collagen fibrils suddenly changing their direction contain knots. These knots of collagen fibrils inside each tendon crimp have been termed "fibrillar crimps", and even if they show different aspects they all may fulfil the same functional role. As integral component of musculoskeletal system, the tendon acts to transmit muscle forces to the skeletal system. There is no complete understanding of the mechanisms in transmitting/absorbing tensional forces within the tendon; however it seems likely that a flattening of tendon crimps may occur at a first stage of tendon stretching. Increasing

  16. Embroidered polymer-collagen hybrid scaffold variants for ligament tissue engineering.

    PubMed

    Hoyer, M; Drechsel, N; Meyer, M; Meier, C; Hinüber, C; Breier, A; Hahner, J; Heinrich, G; Rentsch, C; Garbe, L-A; Ertel, W; Schulze-Tanzil, G; Lohan, A

    2014-10-01

    Embroidery techniques and patterns used for scaffold production allow the adaption of biomechanical scaffold properties. The integration of collagen into embroidered polylactide-co-caprolactone [P(LA-CL)] and polydioxanone (PDS) scaffolds could stimulate neo-tissue formation by anterior cruciate ligament (ACL) cells. Therefore, the aim of this study was to test embroidered P(LA-CL) and PDS scaffolds as hybrid scaffolds in combination with collagen hydrogel, sponge or foam for ligament tissue engineering. ACL cells were cultured on embroidered P(LA-CL) and PDS scaffolds without or with collagen supplementation. Cell adherence, vitality, morphology and ECM synthesis were analyzed. Irrespective of thread size, ACL cells seeded on P(LA-CL) scaffolds without collagen adhered and spread over the threads, whereas the cells formed clusters on PDS and larger areas remained cell-free. Using the collagen hydrogel, the scaffold colonization was limited by the gel instability. The collagen sponge layers integrated into the scaffolds were hardly penetrated by the cells. Collagen foams increased scaffold colonization in P(LA-CL) but did not facilitate direct cell-thread contacts in the PDS scaffolds. The results suggest embroidered P(LA-CL) scaffolds as a more promising basis for tissue engineering an ACL substitute than PDS due to superior cell attachment. Supplementation with a collagen foam presents a promising functionalization strategy. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Study of rheological, viscoelastic and vulcanization behavior of sponge EPDM/NR blended nano- composites

    NASA Astrophysics Data System (ADS)

    Arshad Bashir, M.; Shahid, M.; Ahmed, Riaz; Yahya, A. G.

    2014-06-01

    In this research paper the effect of blending ratio of natural rubber (NR) with Ethylene Propylene Diene Monomer (EPDM) were investigated. Different samples of EPDM/NR ratio were prepared to study the variation of NR in EPDM on rheology, curing characteristics, tangent δ, and viscosity variation during vulcanization of sponge nano composites.The main aim of present research is to develop elastomeric based sponge composites with the blending ratio of base elastomers along with the carbon nano particles for high energy absorbing and damping applications. The curing characteristics, rheology and viscoelastic nature of the composite is remarkably influenced with the progressive blending ratio of the base elastomeric matrix.

  18. Structural studies on Demospongiae sponges from Gökçeada Island in the Northern Aegean Sea

    NASA Astrophysics Data System (ADS)

    Bayari, Sevgi Haman; Şen, Elif Hilal; Ide, Semra; Topaloglu, Bülent

    2018-03-01

    The Demospongiae is the largest Class in the phylum Porifera (sponges). Most sponge species in the Class Demospongiae have a skeleton of siliceous spicules and/or protein spongin or both. The first aim of this study was to perform the morphological and structural characterization of the siliceous spicules of four species belonging to Class Demospongiae (Suberites domuncula, Axinella polypoides, Axinella damicornis and Agelas oroides) collected around Gökçeada Island-Turkey (Northern Aegean Sea). The characterizations were carried out using a combination of Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM/EDX), Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR) and Small Angle X-ray Scattering (SAXS) techniques. The sponge Chondrosia reniformis (Porifera, Demospongiae) lacks a structural skeleton of spicules or the spongin. It consists mainly of a collagenous tissue. The collagen with sponge origin is an important source in biomedical and pharmaceutical applications. The second aim of this study was to provide more information on the molecular structure of collagen of outer (ectosome) and inner (choanosome) regions of the Chondrosia reniformis using ATR-FTIR spectroscopy. Hierarchical clustering analysis (HCA) was also used for the discrimination of ATR-FTIR spectra of species.

  19. Why Do Dolphins Carry Sponges?

    PubMed Central

    Mann, Janet; Sargeant, Brooke L.; Watson-Capps, Jana J.; Gibson, Quincy A.; Heithaus, Michael R.; Connor, Richard C.; Patterson, Eric

    2008-01-01

    Tool use is rare in wild animals, but of widespread interest because of its relationship to animal cognition, social learning and culture. Despite such attention, quantifying the costs and benefits of tool use has been difficult, largely because if tool use occurs, all population members typically exhibit the behavior. In Shark Bay, Australia, only a subset of the bottlenose dolphin population uses marine sponges as tools, providing an opportunity to assess both proximate and ultimate costs and benefits and document patterns of transmission. We compared sponge-carrying (sponger) females to non-sponge-carrying (non-sponger) females and show that spongers were more solitary, spent more time in deep water channel habitats, dived for longer durations, and devoted more time to foraging than non-spongers; and, even with these potential proximate costs, calving success of sponger females was not significantly different from non-spongers. We also show a clear female-bias in the ontogeny of sponging. With a solitary lifestyle, specialization, and high foraging demands, spongers used tools more than any non-human animal. We suggest that the ecological, social, and developmental mechanisms involved likely (1) help explain the high intrapopulation variation in female behaviour, (2) indicate tradeoffs (e.g., time allocation) between ecological and social factors and, (3) constrain the spread of this innovation to primarily vertical transmission. PMID:19066625

  20. Molecular Cloning, Characterization, and Expression Analysis of a Prolyl 4-Hydroxylase from the Marine Sponge Chondrosia reniformis.

    PubMed

    Pozzolini, Marina; Scarfì, Sonia; Mussino, Francesca; Ferrando, Sara; Gallus, Lorenzo; Giovine, Marco

    2015-08-01

    Prolyl 4-hydroxylase (P4H) catalyzes the hydroxylation of proline residues in collagen. P4H has two functional subunits, α and β. Here, we report the cDNA cloning, characterization, and expression analysis of the α and β subunits of the P4H derived from the marine sponge Chondrosia reniformis. The amino acid sequence of the α subunit is 533 residues long with an M r of 59.14 kDa, while the β subunit counts 526 residues with an M r of 58.75 kDa. Phylogenetic analyses showed that αP4H and βP4H are more related to the mammalian sequences than to known invertebrate P4Hs. Western blot analysis of sponge lysate protein cross-linking revealed a band of 240 kDa corresponding to an α2β2 tetramer structure. This result suggests that P4H from marine sponges shares the same quaternary structure with vertebrate homologous enzymes. Gene expression analyses showed that αP4H transcript is higher in the choanosome than in the ectosome, while the study of factors affecting its expression in sponge fragmorphs revealed that soluble silicates had no effect on the αP4H levels, whereas ascorbic acid strongly upregulated the αP4H mRNA. Finally, treatment with two different tumor necrosis factor (TNF)-alpha inhibitors determined a significant downregulation of αP4H gene expression in fragmorphs demonstrating, for the first time in Porifera, a positive involvement of TNF in sponge matrix biosynthesis. The molecular characterization of P4H genes involved in collagen hydroxylation, including the mechanisms that regulate their expression, is a key step for future recombinant sponge collagen production and may be pivotal to understand pathological mechanisms related to extracellular matrix deposition in higher organisms.

  1. Graphene-Montmorillonite Composite Sponge for Safe and Effective Hemostasis.

    PubMed

    Li, Guofeng; Quan, Kecheng; Liang, Yuping; Li, Tianyi; Yuan, Qipeng; Tao, Lei; Xie, Qian; Wang, Xing

    2016-12-28

    Montmorillonite (MMT) is considered to be the most effective hemostat among natural phyllosilicates. However, there is a barrier against using MMT for the commercial hemostatics because the invaded MMT powders might cause thrombosis in vessel. Until now, it is still a challenge to manage the release of MMT and eliminate its side effect. Herein, we present a graphene-MMT composite sponge (GMCS), synthesized under a hydrothermal reaction, fixing MMT powders into the cross-linked graphene sheets. We demonstrate that only a few embedded MMT can evoke remarkable platelet stimulation at the sponge interface, while maintaining fast plasma absorbency of the innate sponge. In the synergy of the above hemostatic mechanisms, the GMCS can rapidly stop bleeding in approximately 85 s in rabbit artery injury test. More importantly, computed tomography angiography certifies that the GMCS does not cause thrombus or blood clot in vessels. Cytotoxicity assay further highlights its biocompatibility. In-depth analysis proposes that two-dimensional graphene overmatches one-dimensional linear polymers in the composite construction, and dimension transformation of blood distribution plays a crucial role for reinforcing the hemostatic performance. This GMCS hemostat not only opens a new perspective for graphene composite, but also makes a new chance of using clays for trauma therapy.

  2. Modified wick method using Weck-Cel sponges for collection of human rectal secretions and analysis of mucosal HIV antibody.

    PubMed

    Kozlowski, P A; Lynch, R M; Patterson, R R; Cu-Uvin, S; Flanigan, T P; Neutra, M R

    2000-08-01

    Weck-Cel sponges were examined for suitability as an absorbent material for nontraumatic collection of rectal secretions in humans. Sponges were tested in vitro and determined by quantitative enzyme-linked immunosorbent assay (ELISA) to be capable of releasing 100% of absorbed albumin and all immunoglobulin subtypes after treatment with detergent-supplemented buffer. Protein composition in rectal secretions collected from normal women with dry sponges (DS) or with sponges previously softened by moistening with saline (MS) was subsequently compared. DS secretions showed evidence of contamination with blood and interstitial fluid-derived albumin, immunoglobulin G (IgG), and monomeric IgA. MS secretions appeared to represent local mucosal secretions more accurately because they contained negligible blood, a greater percentage of secretory IgA within the total IgA, and both lower albumin/IgG ratios and more dramatic alterations in IgG subclass distribution compared with corresponding serum. Anti-HIV IgG, IgM, IgA, and antibodies with secretory component could be demonstrated by ELISA in rectal secretions collected with moist sponges from 8 of 8, 1 of 8, 5 of 8, and 3 of 8 HIV-infected women, respectively. The data show that Weck-Cel sponges, if premoistened, can be used to collect rectal fluids nontraumatically and to obtain quantitative information about concentrations of immunoglobulins and specific antibodies on rectal mucosal surfaces.

  3. The Collagen Family

    PubMed Central

    Ricard-Blum, Sylvie

    2011-01-01

    Collagens are the most abundant proteins in mammals. The collagen family comprises 28 members that contain at least one triple-helical domain. Collagens are deposited in the extracellular matrix where most of them form supramolecular assemblies. Four collagens are type II membrane proteins that also exist in a soluble form released from the cell surface by shedding. Collagens play structural roles and contribute to mechanical properties, organization, and shape of tissues. They interact with cells via several receptor families and regulate their proliferation, migration, and differentiation. Some collagens have a restricted tissue distribution and hence specific biological functions. PMID:21421911

  4. Global Diversity of Sponges (Porifera)

    PubMed Central

    Van Soest, Rob W. M.; Boury-Esnault, Nicole; Vacelet, Jean; Dohrmann, Martin; Erpenbeck, Dirk; De Voogd, Nicole J.; Santodomingo, Nadiezhda; Vanhoorne, Bart; Kelly, Michelle; Hooper, John N. A.

    2012-01-01

    With the completion of a single unified classification, the Systema Porifera (SP) and subsequent development of an online species database, the World Porifera Database (WPD), we are now equipped to provide a first comprehensive picture of the global biodiversity of the Porifera. An introductory overview of the four classes of the Porifera is followed by a description of the structure of our main source of data for this paper, the WPD. From this we extracted numbers of all ‘known’ sponges to date: the number of valid Recent sponges is established at 8,553, with the vast majority, 83%, belonging to the class Demospongiae. We also mapped for the first time the species richness of a comprehensive set of marine ecoregions of the world, data also extracted from the WPD. Perhaps not surprisingly, these distributions appear to show a strong bias towards collection and taxonomy efforts. Only when species richness is accumulated into large marine realms does a pattern emerge that is also recognized in many other marine animal groups: high numbers in tropical regions, lesser numbers in the colder parts of the world oceans. Preliminary similarity analysis of a matrix of species and marine ecoregions extracted from the WPD failed to yield a consistent hierarchical pattern of ecoregions into marine provinces. Global sponge diversity information is mostly generated in regional projects and resources: results obtained demonstrate that regional approaches to analytical biogeography are at present more likely to achieve insights into the biogeographic history of sponges than a global perspective, which appears currently too ambitious. We also review information on invasive sponges that might well have some influence on distribution patterns of the future. PMID:22558119

  5. Collagen vascular disease

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/001223.htm Collagen vascular disease To use the sharing features on ... were previously said to have "connective tissue" or "collagen vascular" disease. We now have names for many ...

  6. Chitosan-aluminum monostearate composite sponge dressing containing asiaticoside for wound healing and angiogenesis promotion in chronic wound.

    PubMed

    Phaechamud, Thawatchai; Yodkhum, Kotchamon; Charoenteeraboon, Juree; Tabata, Yasuhiko

    2015-05-01

    There are many factors that delay healing in chronic wounds including lowering level of growth factors and increasing exudate level comprising high amount of tissue destructive enzymes. Asiaticoside possesses interesting wound healing and angiogenic activities that are employed to stimulate tissue regeneration in wound healing application. This study attempted to develop chitosan-aluminum monostearate (Alst) composite sponge containing asiaticoside for use as an absorbent medical dressing in chronic wound. N-methyl-2-pyrrolidone (NMP) was used to enhance homogeneity of asiaticoside in the polymer composite matrix. The sponge dressings were prepared by lyophilization and dehydrothermal treatment (DHT). Functional group interaction, crystallinity, and morphology of the prepared sponges were investigated using FT-IR, PXRD, and SEM, respectively. Physicochemical properties, porosity, hydrophilic/hydrophobic properties and mechanical property, were evaluated. Wound dressing properties, water vapor transmission rate (WVTR), fluid absorbency, oxygen permeation (OP), and bio-adhesive property, were investigated. In vitro asiaticoside release study was conducted using immersion method. Cytotoxicity was studied in normal human dermal fibroblast (NHDF) and normal human epidermal keratinocyte (NHEK). Angiogenic activity of asiaticoside was evaluated using chick-chorioallantoic membrane (CAM) assay. FT-IR and PXRD results revealed the amidation after DHT to enhance the crystallinity of the prepared sponges. The prepared sponges had high porosity comprising high Alst-loaded amount that exhibited more compact structure. Alst enhanced hydrophobicity therefore it reduced the fluid absorption and WVTR together with bio-adhesion of the prepared sponge dressings. Porosity of all sponges was more than 85% therefore resulting in their high OP. Enhancing hydrophobicity of the material by Alst and more homogeneity caused by NMP eventually retarded the asiaticoside release for 7 days. The

  7. Who Produces Ianthelline? The Arctic Sponge Stryphnus fortis or its Sponge Epibiont Hexadella dedritifera: a Probable Case of Sponge-Sponge Contamination.

    PubMed

    Cárdenas, Paco

    2016-04-01

    The bromotyrosine derivative ianthelline was isolated recently from the Atlantic boreo-arctic deep-sea sponge Stryphnus fortis, and shown to have clear antitumor and antifouling effects. However, chemosystematics, field observations, and targeted metabolic analyses (using UPLC-MS) suggest that ianthelline is not produced by S. fortis but by Hexadella dedritifera, a sponge that commonly grows on S. fortis. This case highlights the importance of combining taxonomic and ecological knowledge to the field of sponge natural products research.

  8. Diaminopropionic Acid Reinforced Graphene Sponge and Its Use for Hemostasis.

    PubMed

    Quan, Kecheng; Li, Guofeng; Tao, Lei; Xie, Qian; Yuan, Qipeng; Wang, Xing

    2016-03-01

    2,3-Diaminopropionic acid (DapA), a medicinal amino acid, is used for the first time to prepare a DapA cross-linked graphene sponge (DCGS) for hemostasis treatment. In a comparison with the reported ethanediamine (EDA) cross-linked graphene sponge (CGS), this carboxyl-functionalized DCGS can not only quickly absorb plasma, but also stimulate erythrocytes and platelets to change their normal form and structure at the interface, which largely affects a cell's metabolism and biofunction, thus further promoting blood coagulation. Whole blood clotting and rat-tail amputation tests indicated that on the basis of the additional interfacial stimulation, the hemostatic efficiency of the DCGS has been significantly improved in comparison with that of the CGS control (P < 0.05). In-depth insight revealed that the increased oxidation degree and the negative charge density play the crucial rule in the enhanced hemostatic performance. The chiral effect contributes mainly to the selective adhesion of erythrocytes and platelets rather than practical hemostasis. Nevertheless, this presentation demonstrated that, on the premise of keeping the fast absorbability, this is an effective method to improve the hemostatic efficiency by enhancing the cell/graphene interface interaction.

  9. UV-responsive nano-sponge for oil absorption and desorption

    PubMed Central

    Kim, Do Hyun; Jung, Min Chan; Cho, So-Hye; Kim, Sang Hoon; Kim, Ho-Young; Lee, Heon Ju; Oh, Kyu Hwan; Moon, Myoung-Woon

    2015-01-01

    Controlled surface wettability for oil has been intensively studied to remove industrial oil waste or oil spill pollution from seas or rivers. In particular, external stimuli-induced special wetting materials, such as photo-responsive TiO2, have attracted considerable attention for oil-water separation. In this study, a novel method is reported to fabricate a nano-sponge which is composed of hydrophobic hydrocarbon and hydrophilic TiO2 nanoparticles for oil absorption or desorption that are responsive to UV irradiation. The hydrocarbon in the nano-sponge could selectively absorb oil from water, whereas the absorbed oil is released into the water by TiO2 in response to UV irradiation. The nano-sponge functionalized porous polydimethylsiloxane released more than 98% of the absorbed crude oil with UV irradiation and air-bubbling. It could be continuously reused while maintaining a high absorption capacity and desorption efficiency without incurring secondary air or water pollution. This smart oil absorption/desorption methodology with excellent selectivity and recyclability with almost perfect removal of absorbed oil can be applied for oil-water separation, oil spill cleanup and reuse of spilled oil. PMID:26260470

  10. Panel Absorber

    NASA Astrophysics Data System (ADS)

    MECHEL, F. P.

    2001-11-01

    A plane wave is incident on a simply supported elastic plate covering a back volume; the arrangement is surrounded by a hard baffle wall. The plate may be porous with a flow friction resistance; the back volume may be filled either with air or with a porous material. The back volume may be bulk reacting (i.e., with sound propagation parallel to the plate) or locally reacting. Since this arrangement is of some importance in room acoustics, Cremer in his book about room acoustics [1] has presented an approximate analysis. However, Cremer's analysis uses a number of assumptions which make his solution, in his own estimate, unsuited for low frequencies, where, on the other hand, the arrangement mainly is applied. This paper presents a sound field description which uses modal analysis. It is applicable not only in the far field, but also near the absorber. Further, approximate solutions are derived, based on simplifying assumptions like Cremer has used. The modal analysis solution is of interest not only as a reference for approximations but also for practical applications, because the aspect of computing time becomes more and more unimportant (the 3D-plots presented below for the sound field were evaluated with modal analysis in about 6 s).

  11. The development of a novel wound healing material, silk-elastin sponge.

    PubMed

    Kawabata, Shingo; Kawai, Katsuya; Somamoto, Satoshi; Noda, Kazuo; Matsuura, Yoshitaka; Nakamura, Yoko; Suzuki, Shigehiko

    2017-12-01

    Silk-elastin is a recombinant protein polymer with repeating units of silk and elastin blocks. This novel wound healing promoting material has the ability to self-assemble from a liquid to a gel. We have already reported that an aqueous solution of silk-elastin has the potential to accelerate wound healing; however, there are several problems in applying silk-elastin in the clinical setting. To solve these problems, we developed a silk-elastin sponge that is easy to use in the clinical setting. In the present study, we examined whether the wound healing effect of the silk-elastin sponge is equal to the aqueous solution of silk-elastin in vivo. The granulation tissue formation promoting effect of the silk-elastin sponge was equal to that of the aqueous solution the silk-elastin, as after application to the wound surface, the sponge was absorbed and dissolved by the exudate. At body temperature the silk-elastin then formed temperature gel. The silk-elastin gel that was obtained contained abundant cytokines from the exudate. We believe that silk-elastin sponge can be applied to various wounds that are difficult to treat with the aqueous solution.

  12. Isolation, Characterization and Biological Evaluation of Jellyfish Collagen for Use in Biomedical Applications

    PubMed Central

    Addad, Sourour; Exposito, Jean-Yves; Faye, Clément; Ricard-Blum, Sylvie; Lethias, Claire

    2011-01-01

    Fibrillar collagens are the more abundant extracellular proteins. They form a metazoan-specific family, and are highly conserved from sponge to human. Their structural and physiological properties have been successfully used in the food, cosmetic, and pharmaceutical industries. On the other hand, the increase of jellyfish has led us to consider this marine animal as a natural product for food and medicine. Here, we have tested different Mediterranean jellyfish species in order to investigate the economic potential of their collagens. We have studied different methods of collagen purification (tissues and experimental procedures). The best collagen yield was obtained using Rhizostoma pulmo oral arms and the pepsin extraction method (2–10 mg collagen/g of wet tissue). Although a significant yield was obtained with Cotylorhiza tuberculata (0.45 mg/g), R. pulmo was used for further experiments, this jellyfish being considered as harmless to humans and being an abundant source of material. Then, we compared the biological properties of R. pulmo collagen with mammalian fibrillar collagens in cell cytotoxicity assays and cell adhesion. There was no statistical difference in cytotoxicity (p > 0.05) between R. pulmo collagen and rat type I collagen. However, since heparin inhibits cell adhesion to jellyfish-native collagen by 55%, the main difference is that heparan sulfate proteoglycans could be preferentially involved in fibroblast and osteoblast adhesion to jellyfish collagens. Our data confirm the broad harmlessness of jellyfish collagens, and their biological effect on human cells that are similar to that of mammalian type I collagen. Given the bioavailability of jellyfish collagen and its biological properties, this marine material is thus a good candidate for replacing bovine or human collagens in selected biomedical applications. PMID:21747742

  13. Isolation, characterization and biological evaluation of jellyfish collagen for use in biomedical applications.

    PubMed

    Addad, Sourour; Exposito, Jean-Yves; Faye, Clément; Ricard-Blum, Sylvie; Lethias, Claire

    2011-01-01

    Fibrillar collagens are the more abundant extracellular proteins. They form a metazoan-specific family, and are highly conserved from sponge to human. Their structural and physiological properties have been successfully used in the food, cosmetic, and pharmaceutical industries. On the other hand, the increase of jellyfish has led us to consider this marine animal as a natural product for food and medicine. Here, we have tested different Mediterranean jellyfish species in order to investigate the economic potential of their collagens. We have studied different methods of collagen purification (tissues and experimental procedures). The best collagen yield was obtained using Rhizostoma pulmo oral arms and the pepsin extraction method (2-10 mg collagen/g of wet tissue). Although a significant yield was obtained with Cotylorhiza tuberculata (0.45 mg/g), R. pulmo was used for further experiments, this jellyfish being considered as harmless to humans and being an abundant source of material. Then, we compared the biological properties of R. pulmo collagen with mammalian fibrillar collagens in cell cytotoxicity assays and cell adhesion. There was no statistical difference in cytotoxicity (p > 0.05) between R. pulmo collagen and rat type I collagen. However, since heparin inhibits cell adhesion to jellyfish-native collagen by 55%, the main difference is that heparan sulfate proteoglycans could be preferentially involved in fibroblast and osteoblast adhesion to jellyfish collagens. Our data confirm the broad harmlessness of jellyfish collagens, and their biological effect on human cells that are similar to that of mammalian type I collagen. Given the bioavailability of jellyfish collagen and its biological properties, this marine material is thus a good candidate for replacing bovine or human collagens in selected biomedical applications.

  14. Surface modification of melamine sponges for pH-responsive oil absorption and desorption

    NASA Astrophysics Data System (ADS)

    Lei, Zhiwen; Zhang, Guangzhao; Deng, Yonghong; Wang, Chaoyang

    2017-09-01

    Inspired by the development of smart oil/water separation materials, a pH responsive melamine sponge has been obtained by grafting poly (4-vinylpyridine) on the skeleton surface through atom transfer radical polymerization. Through scanning electron microscopy and x-ray photoelectron spectroscopy, the successful grafting of poly (4-vinylprridine) onto the melamine sponge has been confirmed. When contacting with different pH water droplets in air, the as-prepared product shows excellent switchable wettability between super-hydrophilicity (0°) and highly hydrophobicity (135°). Meanwhile, this responsive sponge also exhibits super-hydrophilic/oleophobic property underwater at pH = 1.0, and highly hydrophobic/super-oleophilic property in neutral solution at pH = 7.0. Furthermore, the excellent responsiveness is remained after five cycle water contact angle tests between two different pH stages at pH 1.0 and 7.0. The modified melamine sponges could not only absorb the oil from the oily water at pH = 7.0, but also quickly release the absorbed oil underwater at pH = 1.0 without leaving any residues and hurting the environment nearly, showing a good potential in controlled oil/water separation and oil recovery.

  15. Novel fabrication of a robust superhydrophobic PU@ZnO@Fe3O4@SA sponge and its application in oil-water separations.

    PubMed

    Tran, Viet-Ha Thi; Lee, Byeong-Kyu

    2017-12-13

    We report a novel superhydrophobic material based on commercially available polyurethane (PU) sponge with high porosity, low density and good elasticity. The fabrication of a superhydrophobic sponge capable of efficiently separating oil from water was achieved by imitating or mimicking nature's designs. The original PU sponge was coated with zinc oxide (ZnO), stearic acid (SA) and iron oxide particles (Fe 3 O 4 ) via a facile and environmentally friendly method. After each treatment, the properties of the modified sponge were characterized, and the changes in wettability were examined. Water contact angle (WCA) measurements confirmed the excellent superhydrophobicity of the material withhigh static WCA of 161° andlow dynamic WCA (sliding WCA of 7° and shedding WCA of 8°). The fabricated sponge showed high efficiency in separation (over 99%) of different oils from water. Additionally, the fabricated PU@ZnO@Fe 3 O 4 @SA sponge could be magnetically guided to quickly absorb oil floating on the water surface. Moreover, the fabricated sponge showed excellent stability and reusability in terms of superhydrophobicity and oil absorption capacity. The durable, magnetic and superhydrophobic properties of the fabricated sponge render it applicable to the cleanup of marine oil spills and other oil-water separation issues, with eco-friendly recovery of the oil by simple squeezing process.

  16. Ultralight Fe@C Nanocapsules/Sponge Composite with Reversibly Tunable Microwave Absorption Performances.

    PubMed

    Li, Yixing; Mao, Zhe; Liu, Rongge; Zhao, Xiaoning; Zhang, Yanhui; Qin, Gaowu; Zhang, Xuefeng

    2017-08-11

    Microwave absorbers are usually designed to solve electromagnetic interferences at a specific frequency, while the requirements may be dynamic during service life. Therefore, a recoverable tuning for microwave absorption properties in response to an external stimulus would be highly desirable. We herein present a micro/nano-scale hybrid absorber, in which high-performance Fe@C nanocapsule absorbents are integrated with a porous melamine sponge skeleton, exhibiting multiple merits of light weight, strong absorption and high elasticity. By mechanically compressing and decompressing the absorber, microwave absorption performances can be effectively shifted between 18 GHz and 26.5 GHz. The present study thus provides a new strategy for the design of a 'dynamic' microwave absorber.

  17. Ultralight Fe@C Nanocapsules/Sponge Composite with Reversibly Tunable Microwave Absorption Performances

    NASA Astrophysics Data System (ADS)

    Li, Yixing; Mao, Zhe; Liu, Rongge; Zhao, Xiaoning; Zhang, Yanhui; Qin, Gaowu; Zhang, Xuefeng

    2017-08-01

    Microwave absorbers are usually designed to solve electromagnetic interferences at a specific frequency, while the requirements may be dynamic during service life. Therefore, a recoverable tuning for microwave absorption properties in response to an external stimulus would be highly desirable. We herein present a micro/nano-scale hybrid absorber, in which high-performance Fe@C nanocapsule absorbents are integrated with a porous melamine sponge skeleton, exhibiting multiple merits of light weight, strong absorption and high elasticity. By mechanically compressing and decompressing the absorber, microwave absorption performances can be effectively shifted between 18 GHz and 26.5 GHz. The present study thus provides a new strategy for the design of a ‘dynamic’ microwave absorber.

  18. Competitive interactions between sponge-associated bacteria.

    PubMed

    Esteves, Ana I S; Cullen, Alescia; Thomas, Torsten

    2017-03-01

    The diversity of the microbial communities associated with marine sponges has been extensively studied, but their functioning and interactions within the sponge holobiont are only recently being appreciated. Sponge-associated microorganisms are known for the production of a range of inhibitory metabolites with biotechnological application, but the ecological role that these compounds remains elusive. In this work, we explore the competitive interactions between cultivated sponge-associated bacteria to inspect whether bacteria that produce antimicrobial activities are able to inhibit potentially pathogenic bacteria. We isolated a Bacillus sp. bacterium with sponge-degrading activity, which likely has a negative impact on the host. This bacterium, along with other sponge isolates from the same genus, was found to be inhibited by a subpopulation of closely related sponge-derived Pseudovibrio spp. In some Pseudovibrio strains, these inhibitory activities were correlated with the genetic capacity to produce polyketides, such as erythronolide. Our observations suggest that antagonistic activities likely influence the composition of the sponge microbiome, including the abundance of bacteria that can be harmful to the host. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Metal sponge for cryosorption pumping applications

    DOEpatents

    Myneni, G.R.; Kneisel, P.

    1995-12-26

    A system has been developed for adsorbing gases at high vacuum in a closed area. The system utilizes large surface clean anodized metal surfaces at low temperatures to adsorb the gases. The large surface clean anodized metal is referred to as a metal sponge. The metal sponge generates or maintains the high vacuum by increasing the available active cryosorbing surface area. 4 figs.

  20. Metal sponge for cryosorption pumping applications

    DOEpatents

    Myneni, Ganapati R.; Kneisel, Peter

    1995-01-01

    A system has been developed for adsorbing gases at high vacuum in a closed area. The system utilizes large surface clean anodized metal surfaces at low temperatures to adsorb the gases. The large surface clean anodized metal is referred to as a metal sponge. The metal sponge generates or maintains the high vacuum by increasing the available active cryosorbing surface area.

  1. Cutaneous Collagenous Vasculopathy

    PubMed Central

    Ortleb, Melanie; Boyd, Alan S.; Powers, Jennifer

    2015-01-01

    Cutaneous collagenous vasculopathy is a rare microangiopathy of dermal blood vessels. Clinically indistinguishable from generalized essential telangiectasia, this condition is diagnosed by its unique histological appearance. In contrast to other primary telangiectatic processes, cutaneous collagenous vasculopathy has dilated vascular structures that contain deposits of eosinophilic hyaline material within the vessel walls. To date, cutaneous collagenous vasculopathy has been described in a total of 19 cases in the medical literature. The first several cases were described exclusively in middle-aged to elderly men. Though it has now been described in both men and women, cutaneous collagenous vasculopathy is still most often described in middle-aged to older adults. No particular disease or medication has been linked to the development of cutaneous collagenous vasculopathy, and the etiology remains unknown. In this case series, the authors present three additional patients diagnosed with cutaneous collagenous vasculopathy and discuss their clinical and histopathologic features. PMID:26705441

  2. Deamidation of collagen.

    PubMed

    Hurtado, Pilar Perez; O'Connor, Peter B

    2012-03-20

    Collagen is the major component of skin, tendons, ligaments, teeth, and bones, it provides the framework that holds most multicellular animals together, and collagen type I constitutes the major fibrillar collagen of bone. Because of the complexity of collagen's structure, the study of post-translational modifications such as deamidation for this protein is challenging. Although there is no evidence of this protein being used for age assessment, it has been shown that deamidation of collagen is remarkably increased in old bones from mammals. Nonspectrometric methodologies have been used for the determination of the extent of deamidation as a measure of the amount of amide nitrogen released in ammonia as well as constant rates for deamidation of asparagine in collagen. In general, these methodologies required more sample and separation processes. To understand if collagen plays a significant role in the aging process of fossil materials, a simpler and more accurate method is needed to determine the extent of deamidation at the whole protein level. The present work shows a method to determine the extent of deamidation in collagen using Fourier transform ion cyclotron resonance-mass spectrometry (FTICR-MS) along with collisionally activated dissociation (CAD) and electron capture dissociation (ECD). The measured deamidation half-life for three different tryptic peptides from collagen (I) ranged from 2000 to 6000 s under high temperature conditions (∼62 °C) and pH 7.5.

  3. Enigmatic insight into collagen

    PubMed Central

    Deshmukh, Shrutal Narendra; Dive, Alka M; Moharil, Rohit; Munde, Prashant

    2016-01-01

    Collagen is a unique, triple helical molecule which forms the major part of extracellular matrix. It is the most abundant protein in the human body, representing 30% of its dry weight. It is the fibrous structural protein that makes up the white fibers (collagen fibers) of skin, tendons, bones, cartilage and all other connective tissues. Collagens are not only essential for the mechanical resistance and resilience of multicellular organisms, but are also signaling molecules defining cellular shape and behavior. The human body has at least 16 types of collagen, but the most prominent types are I, II and III. Collagens are produced by several cell types and are distinguishable by their molecular compositions, morphologic characteristics, distribution, functions and pathogenesis. This is the major fibrous glycoprotein present in the extracellular matrix and in connective tissue and helps in maintaining the structural integrity of these tissues. It has a triple helical structure. Various studies have proved that mutations that modify folding of the triple helix result in identifiable genetic disorders. Collagen diseases share certain similarities with autoimmune diseases, because autoantibodies specific to each collagen disease are produced. Therefore, this review highlights the role of collagen in normal health and also the disorders associated with structural and functional defects in collagen. PMID:27601823

  4. Gap junction communications influence upon fibroblast synthesis of Type I collagen and fibronectin.

    PubMed

    Ehrlich, H Paul; Sun, Bonnie; Saggers, Gregory C; Kromath, Fatuma

    2006-07-01

    In rats polyvinyl alcohol sponge subcutaneous implants treated with gap junctional intercellular communications (GJIC) uncouplers showed reduced deposition of connective tissue. Do uncouplers inhibit the synthesis and deposition of a new connective tissue by fibroblasts? Confluent human dermal fibroblasts in serum-free medium received either endosulfan or oleamide, GJIC uncouplers. Collected media were subjected to Dot Blot analysis for native Type I collagen and fibronectin. Uncoupler-treated fibroblasts released less Type I collagen, while there was no change in fibronectin release. Collagen synthesis was restored to normal, when the uncouplers were removed, showing that these uncouplers were reversible and not toxic to cells. Northern blot analysis revealed procollagen alpha1 (I) mRNA was minimally affected by endosulfan. Oleamide-treated 17-day chick embryo calvaria explants were incubated with Type I collagen antibody, frozen, cryosectioned, and then subjected to rhodamine (Rh) tagged anti-mouse-IgG antibody, to detect newly deposited Type I collagen. Fluorescent antibody-collagen complexes were localized on the periphery of cells in control calvaria, but absent around cells in oleamide-treated calvaria. GJIC optimize collagen synthesis but not fibronectin synthesis. The lack of connective tissue deposited in granulation tissues treated with uncouplers appears related to the inhibition of collagen synthesis. These findings suggest that altering GJIC might control collagen deposition in scarring. 2006 Wiley-Liss, Inc.

  5. A novel fish collagen scaffold as dural substitute.

    PubMed

    Li, Qing; Mu, Lanlan; Zhang, Fenghua; Sun, Yue; Chen, Quan; Xie, Cuicui; Wang, Hongmei

    2017-11-01

    The novel fish collagen scaffolds were prepared by lyophilization. The collagen sponges and chitosan were chemically cross-linked with the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) as a cross-linking agent by pressing in one special mould. The collagen scaffolds were analyzed by scanning electron microscopy (SEM) and mechanical property, and the in vitro collagenase degradation was tested. The results revealed that the scaffold has a suitable porosity, elasticity and prevent fluid leakage, suggesting potential applications in the tissue-engineered. In vitro collagenase degradation demonstrated that the collagen cross-linking with EDC by pressing played an important role in their resistance to biodegradation. Moreover, the scaffold proved excellent biocompatibility for the activity and proliferation of mouse embryonic fibroblasts cells (MEFs) in vitro. The rabbit dural defect model demonstrated that the scaffolds could prevent brain tissue adhesion, which reduce the opportunity of inflammation, facilitate the growth of fibroblasts and enhance the tissue regeneration and healing. The novel fish collagen scaffold as dural substitute, demonstrate a capability for using in the field of tissue engineering. Copyright © 2017. Published by Elsevier B.V.

  6. Molecular characterization and expression analysis of the first Porifera tumor necrosis factor superfamily member and of its putative receptor in the marine sponge Chondrosia reniformis.

    PubMed

    Pozzolini, Marina; Scarfì, Sonia; Ghignone, Stefano; Mussino, Francesca; Vezzulli, Luigi; Cerrano, Carlo; Giovine, Marco

    2016-04-01

    Here we report the molecular cloning and characterization of the first Tumor Necrosis Factor homologous and of its putative receptor in the marine sponge Chondrosia reniformis: chTNF and chTNFR, respectively. The deduced chTNF amino acid sequence is a type II transmembrane protein containing the typical TNFSF domain. Phylogenetic analysis reveals that chTNF is more related to Chordata TNFs rather than to other invertebrates. chTNF and chTNFR are constitutively expressed both in the ectosome and in the choanosome of the sponge, with higher levels in the ectosome. chTNF and chTNFR mRNAs were monitored in sponge fragmorphs treated with Gram(+) or Gram(-) bacteria. chTNF was significantly upregulated in Gram(+)-treated fragmorphs as compared to controls, while chTNFR was upregulated by both treatments. Finally, the possible chTNF fibrogenic role in sponge fragmorphs was studied by TNF inhibitor treatment measuring fibrillar and non fibrillar collagen gene expression; results indicate that the cytokine is involved in sponge collagen deposition and homeostasis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Haemorrhoids - a collagen disease?

    PubMed

    Willis, S; Junge, K; Ebrahimi, R; Prescher, A; Schumpelick, V

    2010-12-01

    The cause of haemorrhoidal disease is unknown, epidemiological data and histopathological findings support the hypothesis that reduced connective tissue stability is associated with the incidence of haemorrhoids. Therefore the aim of this study was to analyse the quantity and quality of collagen formation in the corpus cavernosum recti in patients with III°/IV° haemorrhoids in comparison with persons without haemorrhoids. Haemorrhoidectomy specimens of 31 patients with III°/IV° haemorrhoids were examined. The specimens of 20 persons who died a natural death and who had no haemorrhoidal disease served as the controls. The amount of collagen was estimated photometrically by calculating the collagen/protein ratio. The collagen I/III ratio served as parameter for the quality of collagen formation and was calculated using cross polarization spectroscopy. Patients with haemorrhoids had a significantly reduced collagen/protein ratio (42.2 ± 16.2μg/mg vs 72.5±31.0μg/mg; P= 0.02) and a significantly reduced collagen I/III ratio (2.0±0.1 vs 4.6±0.3; P<0.001) compared with persons without haemorrhoidal disease. There was no correlation with patients' age or gender.  There is a fundamental disorder of collagen metabolism in patients with haemorrhoidal disease. It remains unclear whether this is due to exogenous or endogenous influences. © 2010 The Authors. Colorectal Disease © 2010 The Association of Coloproctology of Great Britain and Ireland.

  8. Collagen: Biochemistry, biomechanics, biotechnology

    SciTech Connect

    Nimni, M.E.

    1988-01-01

    This book is an up-to-date reference for new ideas, information, and concepts in collagen research. The first volume emphasizes the relationship between the molecular structure and function of collagen, including descriptions of collagen types which exist in tissues as well as how these molecules organize into fibrils and the nature of the chemical crosslinks which stabilize them. In Volume II the biomechanical behavior of various specialized tissues, abnormal accumulation of collagen in the form of scars of fibrous infiltration are examined/and wound healing, tissue regulation and repair are covered in detail. Volume III explores the increasing application of collagen technologymore » to the field of bioprosthesis, including the production of heart valve bioprosthesis, blood vessels, ligament substitutes, and bone substitutes.« less

  9. Preparation and oil absorption properties of magnetic melamine sponge

    NASA Astrophysics Data System (ADS)

    Lei, LUO; Jia-qi, HU; Na, LV

    2017-12-01

    The magnetic melamine sponge (MS-Fe3O4) with magnetic response and high hydrophobicity was fabricated by two-step method. First, the magnetic nano-particles were fixed on the skeleton of melamine sponge (MS) using 3-hydroxytyramine hydrochloride and 1-dodecanethiol, then hydrophobicity modified with octadecyltrichlorosilane (OTS). The structures and chemical compositions of MS and MS-Fe3O4 were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The wettability of the sample was obtained by using contact angle analysis system. MS-Fe3O4 endowed with outstanding selectivity and excellent oil absorption capacities, which can be widely used in absorbing various sorts of oil. The oil absorption capacities for crude oil, diesel oil, lubricating oil, soybean oil and peanut oil were 71g/g, 51g/g, 62g/g, 54g/g, 57g/g. In addition, MS-Fe3O4 showed excellent recyclability which can be forecasted as an ideal candidate for oil-water separation.

  10. Cell Population Kinetics of Collagen Scaffolds in Ex Vivo Oral Wound Repair

    PubMed Central

    Agis, Hermann; Collins, Amy; Taut, Andrei D.; Jin, Qiming; Kruger, Laura; Görlach, Christoph; Giannobile, William V.

    2014-01-01

    Biodegradable collagen scaffolds are used clinically for oral soft tissue augmentation to support wound healing. This study sought to provide a novel ex vivo model for analyzing healing kinetics and gene expression of primary human gingival fibroblasts (hGF) within collagen scaffolds. Sponge type and gel type scaffolds with and without platelet-derived growth factor-BB (PDGF) were assessed in an hGF containing matrix. Morphology was evaluated with scanning electron microscopy, and hGF metabolic activity using MTT. We quantitated the population kinetics within the scaffolds based on cell density and distance from the scaffold border of DiI-labled hGFs over a two-week observation period. Gene expression was evaluated with gene array and qPCR. The sponge type scaffolds showed a porous morphology. Absolute cell number and distance was higher in sponge type scaffolds when compared to gel type scaffolds, in particular during the first week of observation. PDGF incorporated scaffolds increased cell numbers, distance, and formazan formation in the MTT assay. Gene expression dynamics revealed the induction of key genes associated with the generation of oral tissue. DKK1, CYR61, CTGF, TGFBR1 levels were increased and integrin ITGA2 levels were decreased in the sponge type scaffolds compared to the gel type scaffold. The results suggest that this novel model of oral wound healing provides insights into population kinetics and gene expression dynamics of biodegradable scaffolds. PMID:25397671

  11. [Use of "gelatamp" colloidal silver gelatin sponge to prevent dry socket after extracting mandibular impacted teeth].

    PubMed

    Wang, Yao-zhong; Guan, Qun-li; Li, Ya-xin; Guo, Ji-lai; Jiang, Ling; Jia, Mu-yun; Deng, Yue

    2013-02-01

    To study the clinical effect of "gelatamp" colloidal silver gelatin sponge on preventing dry socket after extracting the mandibular impacted teeth. 1350 teeth extracted from 976 patients who needed to extract the mandibular impacted teeth were divided into group A, group B and group C randomly. "Gelatamp" colloidal silver gelatin sponge was implanted into alveolar socket after teeth extraction in group A, with absorbable gelatin sponge was implanted into alveolar socket in group B and nothing was implanted into alveolar socket in group C. The incidence of dry socket was observed, the data was analyzed using SPSS10.0 software package. The incidence of dry socket was 0.44% in group A, 2% in group B and 4.44% in group C. There was significant difference in the incidence of dry socket between group A and group C(P<0.01). There was also significant difference between group B and group C(P<0.05) and between group A and group B(P<0.05). The results demonstrate that "gelatamp" colloidal silver gelatin sponge can prevent the occurrence of dry socket after teeth extraction, which is of wide clinical use.

  12. Magnetic sponge prepared with an alkanedithiol-bridged network of nanomagnets.

    PubMed

    Ito, Yoshikazu; Miyazaki, Akira; Takai, Kazuyuki; Sivamurugan, Vajiravelu; Maeno, Takashi; Kadono, Takeshi; Kitano, Masaaki; Ogawa, Yoshihiro; Nakamura, Naotake; Hara, Michikazu; Valiyaveettil, Suresh; Enoki, Toshiaki

    2011-08-03

    The magnetic dipole-dipole interaction between nanomagnets having huge magnetic moments can have a strength comparable to that of the van der Waals interaction between them, and it can be manipulated by applying an external magnetic field of conventional strength. Therefore, the cooperation between the dipole-dipole interaction and the applied magnetic field allows the magnetic moments of nanomagnets to be aligned and organized in an ordered manner. In this work, a network of magnetic nanoparticles connected with flexible long-alkyl-chain linkers was designed to develop a "magnetic sponge" capable of absorbing and desorbing guest molecules with changes in the applied magnetic field. The magnetization of the sponge with long-alkyl-chain bridges (30 C atoms) exhibited a 500% increase after cooling in the presence of an applied field of 7 T relative to that in the absence of a magnetic field. Cooling in a magnetic field leads to anisotropic stretching in the sponge due to reorganization of the nanomagnets along the applied field, in contrast to the isotropic organization under zero-field conditions. Such magnetic-responsive organization and reorganization of the magnetic particle network significantly influences the gas absorption capacity of the nanopores inside the material. The absorption and desorption of guests in an applied magnetic field at low temperature can be regarded as a fascinating "breathing feature" of our magnetic sponge.

  13. Release of antibiotics from collagen dressing.

    PubMed

    Grzybowski, J; Antos-Bielska, M; Ołdak, E; Trafny, E A

    1997-01-01

    Our new collagen dressing has been developed recently. Three types (A, B, and C) of the dressing were prepared in this study. Each type contained bacitracin, neomycin or colistin. The antibiotic was input into: i. collagen sponge (CS)--type A, ii. layer of limited hydrophobicity (LLH)--type B, and iii. into both CS and LLH layers--type C. The final concentration of the antibiotic that resulted from the loading level was 2 mg/cm2 for the dressings of type A and B and 4 mg/cm2 for the dressing of type C. The antibiotics were then extracted from the pieces of dressings for two days through dialysis membrane. Susceptibility of 54 bacterial strains (S. aureus, P. aeruginosa, and Acinetobacter) isolated from burn wounds were tested to the three antibiotics used for preparation of the dressings. The results of the study evidenced that efficiency of released of antibiotics into the extracts depended on the kind of antibiotic and on the type of dressing. The concentration of the antibiotics proved to be much higher than MIC90 values of the bacterial isolates tested in respect to their susceptibility. The dressing containing mixture of the three antibiotics in two layers--CS and LLH is now considered as potentially effective for care of infected wounds. It may be useful for the treatment of infected wounds or for profilaxis of contaminated wounds, ensuring: i. sufficient antimicrobial activity in wound, and ii. optimal wound environment for the presence of collagenic biomaterial on the damaged tissue.

  14. Evaluation of rhBMP-2/collagen/TCP-HA bone graft with and without bone marrow cells in the canine femoral multi defect model.

    PubMed

    Luangphakdy, V; Shinohara, K; Pan, H; Boehm, C; Samaranska, A; Muschler, G F

    2015-01-12

    Recombinant human bone morphogenetic protein-2, when applied to an absorbable type 1 bovine collagen sponge (rhBMP-2/ACS) is an effective therapy in many bone grafting settings. Bone marrow aspirate (BMA) has also been used as a source of transplantable osteogenic connective tissue progenitors. This study was designed to characterize the performance of a scaffold comprising rhBMP-2/ACS in which the sponge wraps around tri-calcium phosphate hydroxyapatite granules (rhBMP-2/ACS/TCP-HA) and to test the hypothesis that addition of BMA will improve the performance of this construct in the Canine Femoral Multi Defect Model. In each subject, two sites were grafted with rhBMP-2/ACS/TCP-HA scaffold loaded with BMA clot and two other sites with rhBMP-2/ACS/TCP-HA scaffold loaded with wound blood (WB). After correction for unresorbed TCP-HA granules, sites grafted with rhBMP-2/ACS/TCP-HA+BMA and rhBMP-2/ACS/TCP-HA+WB were similar, with mean percent bone volumes of 10.9 %±1.2 and 11.2 %±1.2, respectively. No differences were seen in quantitative histomorphometry. While bone formation using both constructs was robust, this study did not support the hypothesis that the addition of unprocessed bone marrow aspirate clot improved bone regeneration in a site engrafted with rhBMP-2/ACS/TCP-HA+BMA. In contrast to prior studies using this model, new bone formation was greater at the center of the defect where TCP-HA was distributed. This finding suggests a potential synergy between rhBMP-2 and the centrally placed ceramic and cellular components of the graft construct. Further optimization may also require more uniform distribution of TCP-HA, alternative cell delivery strategies, and a more rigorous large animal segmental defect model.

  15. Collagen Quantification in Tissue Specimens.

    PubMed

    Coentro, João Quintas; Capella-Monsonís, Héctor; Graceffa, Valeria; Wu, Zhuning; Mullen, Anne Maria; Raghunath, Michael; Zeugolis, Dimitrios I

    2017-01-01

    Collagen is the major extracellular protein in mammals. Accurate quantification of collagen is essential in the biomaterials (e.g., reproducible collagen scaffold fabrication), drug discovery (e.g., assessment of collagen in pathophysiologies, such as fibrosis), and tissue engineering (e.g., quantification of cell-synthesized collagen) fields. Although measuring hydroxyproline content is the most widely used method to quantify collagen in biological specimens, the process is very laborious. To this end, the Sircol™ Collagen Assay is widely used due to its inherent simplicity and convenience. However, this method leads to overestimation of collagen content due to the interaction of Sirius red with basic amino acids of non-collagenous proteins. Herein, we describe the addition of an ultrafiltration purification step in the process to accurately determine collagen content in tissues.

  16. Formation mechanism and biological activity of novel thiolated human-like collagen iron complex.

    PubMed

    Zhu, Chenhui; Liu, Lingyun; Deng, Jianjun; Ma, Xiaoxuan; Hui, Junfeng; Fan, Daidi

    2016-03-01

    To develop an iron supplement that is effectively absorbed and utilized, thiolated human-like collagen was created to improve the iron binding capacity of human-like collagen. A thiolated human-like collagen-iron complex was prepared in a phosphate buffer, and one mole of thiolated human-like collagen-iron possessed approximately 28.83 moles of iron. The characteristics of thiolated human-like collagen-iron were investigated by ultraviolet-visible absorption spectroscopy, Fourier transform infrared spectroscopy, circular dichroism, and differential scanning calorimetry. The results showed that the thiolated human-like collagen-iron complex retained the secondary structure of human-like collagen and had greater thermodynamic stability than human-like collagen, although interactions between iron ions and human-like collagen occurred during the formation of the complex. In addition, to evaluate the bioavailability of thiolated human-like collagen-iron, an in vitro Caco-2 cell model and an in vivo iron deficiency anemia mouse model were employed. The data demonstrated that the thiolated human-like collagen-iron complex exhibited greater bioavailability and was more easily utilized than FeSO4, ferric ammonium citrate, or ferrous glycinate. These results indicated that the thiolated human-like collagen-iron complex is a potential iron supplement in the biomedical field. © The Author(s) 2016.

  17. Determination of the Absolute Configuration of the Pseudo-Symmetric Natural Product Elatenyne by the Crystalline Sponge Method.

    PubMed

    Urban, Sylvia; Brkljača, Robert; Hoshino, Manabu; Lee, Shoukou; Fujita, Makoto

    2016-02-18

    Elatenyne is a marine natural product that was isolated in 1986. Despite its simple 2,2'-bifuranyl backbone, its relative structure was only recently determined. The absolute configuration of elatenyne has still not been unequivocally confirmed because of its pseudo-meso core structure, which results in a specific rotation, [α]D  , of almost zero. In this work, the structure of natural elatenyne was determined by the crystalline sponge method and the use of a porous coordination network (a crystalline sponge) capable of absorbing organic guests; in the sponge, the absorbed guests are ordered and crystallographically observable. The crystalline sponge could differentiate between the two very similar alkyl side chains, and the absolute structure of elatenyne was thus reliably determined. The total amount required for the experiments was only approximately 100 μg, and the majority (95 μg) could be recovered after the experiments. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Application of thermal model for pan evaporation to the hydrology of a defined medium, the sponge

    NASA Technical Reports Server (NTRS)

    Trenchard, M. H.; Artley, J. A. (Principal Investigator)

    1981-01-01

    A technique is presented which estimates pan evaporation from the commonly observed values of daily maximum and minimum air temperatures. These two variables are transformed to saturation vapor pressure equivalents which are used in a simple linear regression model. The model provides reasonably accurate estimates of pan evaporation rates over a large geographic area. The derived evaporation algorithm is combined with precipitation to obtain a simple moisture variable. A hypothetical medium with a capacity of 8 inches of water is initialized at 4 inches. The medium behaves like a sponge: it absorbs all incident precipitation, with runoff or drainage occurring only after it is saturated. Water is lost from this simple system through evaporation just as from a Class A pan, but at a rate proportional to its degree of saturation. The contents of the sponge is a moisture index calculated from only the maximum and minium temperatures and precipitation.

  19. Environmental Shaping of Sponge Associated Archaeal Communities

    PubMed Central

    Turque, Aline S.; Batista, Daniela; Silveira, Cynthia B.; Cardoso, Alexander M.; Vieira, Ricardo P.; Moraes, Fernando C.; Clementino, Maysa M.; Albano, Rodolpho M.; Paranhos, Rodolfo; Martins, Orlando B.; Muricy, Guilherme

    2010-01-01

    Background Archaea are ubiquitous symbionts of marine sponges but their ecological roles and the influence of environmental factors on these associations are still poorly understood. Methodology/Principal Findings We compared the diversity and composition of archaea associated with seawater and with the sponges Hymeniacidon heliophila, Paraleucilla magna and Petromica citrina in two distinct environments: Guanabara Bay, a highly impacted estuary in Rio de Janeiro, Brazil, and the nearby Cagarras Archipelago. For this we used metagenomic analyses of 16S rRNA and ammonia monooxygenase (amoA) gene libraries. Hymeniacidon heliophila was more abundant inside the bay, while P. magna was more abundant outside and P. citrina was only recorded at the Cagarras Archipelago. Principal Component Analysis plots (PCA) generated using pairwise unweighted UniFrac distances showed that the archaeal community structure of inner bay seawater and sponges was different from that of coastal Cagarras Archipelago. Rarefaction analyses showed that inner bay archaeaoplankton were more diverse than those from the Cagarras Archipelago. Only members of Crenarchaeota were found in sponge libraries, while in seawater both Crenarchaeota and Euryarchaeota were observed. Although most amoA archaeal genes detected in this study seem to be novel, some clones were affiliated to known ammonia oxidizers such as Nitrosopumilus maritimus and Cenarchaeum symbiosum. Conclusion/Significance The composition and diversity of archaeal communities associated with pollution-tolerant sponge species can change in a range of few kilometers, probably influenced by eutrophication. The presence of archaeal amoA genes in Porifera suggests that Archaea are involved in the nitrogen cycle within the sponge holobiont, possibly increasing its resistance to anthropogenic impacts. The higher diversity of Crenarchaeota in the polluted area suggests that some marine sponges are able to change the composition of their associated

  20. Electrospun tilapia collagen nanofibers accelerating wound healing via inducing keratinocytes proliferation and differentiation.

    PubMed

    Zhou, Tian; Wang, Nanping; Xue, Yang; Ding, Tingting; Liu, Xin; Mo, Xiumei; Sun, Jiao

    2016-07-01

    The development of biomaterials with the ability to induce skin wound healing is a great challenge in biomedicine. In this study, tilapia skin collagen sponge and electrospun nanofibers were developed for wound dressing. The collagen sponge was composed of at least two α-peptides. It did not change the number of spleen-derived lymphocytes in BALB/c mice, the ratio of CD4(+)/CD8(+) lymphocytes, and the level of IgG or IgM in Sprague-Dawley rats. The tensile strength and contact angle of collagen nanofibers were 6.72±0.44MPa and 26.71±4.88°, respectively. They also had good thermal stability and swelling property. Furthermore, the nanofibers could significantly promote the proliferation of human keratinocytes (HaCaTs) and stimulate epidermal differentiation through the up-regulated gene expression of involucrin, filaggrin, and type I transglutaminase in HaCaTs. The collagen nanofibers could also facilitate rat skin regeneration. In the present study, electrospun biomimetic tilapia skin collagen nanofibers were succesfully prepared, were proved to have good bioactivity and could accelerate rat wound healing rapidly and effectively. These biological effects might be attributed to the biomimic extracellular matrix structure and the multiple amino acids of the collagen nanofibers. Therefore, the cost-efficient tilapia collagen nanofibers could be used as novel wound dressing, meanwhile effectively avoiding the risk of transmitting animal disease in the future clinical apllication. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Comparison of artificial absorbing boundaries for acoustic wave equation modelling

    NASA Astrophysics Data System (ADS)

    Gao, Yingjie; Song, Hanjie; Zhang, Jinhai; Yao, Zhenxing

    2017-12-01

    Absorbing boundary conditions are necessary in numerical simulation for reducing the artificial reflections from model boundaries. In this paper, we overview the most important and typical absorbing boundary conditions developed throughout history. We first derive the wave equations of similar methods in unified forms; then, we compare their absorbing performance via theoretical analyses and numerical experiments. The Higdon boundary condition is shown to be the best one among the three main absorbing boundary conditions that are based on a one-way wave equation. The Clayton and Engquist boundary is a special case of the Higdon boundary but has difficulty in dealing with the corner points in implementaion. The Reynolds boundary does not have this problem but its absorbing performance is the poorest among these three methods. The sponge boundary has difficulties in determining the optimal parameters in advance and too many layers are required to achieve a good enough absorbing performance. The hybrid absorbing boundary condition (hybrid ABC) has a better absorbing performance than the Higdon boundary does; however, it is still less efficient for absorbing nearly grazing waves since it is based on the one-way wave equation. In contrast, the perfectly matched layer (PML) can perform much better using a few layers. For example, the 10-layer PML would perform well for absorbing most reflected waves except the nearly grazing incident waves. The 20-layer PML is suggested for most practical applications. For nearly grazing incident waves, convolutional PML shows superiority over the PML when the source is close to the boundary for large-scale models. The Higdon boundary and hybrid ABC are preferred when the computational cost is high and high-level absorbing performance is not required, such as migration and migration velocity analyses, since they are not as sensitive to the amplitude errors as the full waveform inversion.

  2. 16 CFR 501.6 - Cellulose sponges, irregular dimensions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Cellulose sponges, irregular dimensions. 501... REQUIREMENTS AND PROHIBITIONS UNDER PART 500 § 501.6 Cellulose sponges, irregular dimensions. Variety packages of cellulose sponges of irregular dimensions, are exempted from the requirements of § 500.25 of this...

  3. 16 CFR 501.6 - Cellulose sponges, irregular dimensions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Cellulose sponges, irregular dimensions. 501... REQUIREMENTS AND PROHIBITIONS UNDER PART 500 § 501.6 Cellulose sponges, irregular dimensions. Variety packages of cellulose sponges of irregular dimensions, are exempted from the requirements of § 500.25 of this...

  4. 16 CFR 501.6 - Cellulose sponges, irregular dimensions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Cellulose sponges, irregular dimensions. 501... REQUIREMENTS AND PROHIBITIONS UNDER PART 500 § 501.6 Cellulose sponges, irregular dimensions. Variety packages of cellulose sponges of irregular dimensions, are exempted from the requirements of § 500.25 of this...

  5. 16 CFR 501.6 - Cellulose sponges, irregular dimensions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Cellulose sponges, irregular dimensions. 501... REQUIREMENTS AND PROHIBITIONS UNDER PART 500 § 501.6 Cellulose sponges, irregular dimensions. Variety packages of cellulose sponges of irregular dimensions, are exempted from the requirements of § 500.25 of this...

  6. 16 CFR 501.6 - Cellulose sponges, irregular dimensions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Cellulose sponges, irregular dimensions. 501... REQUIREMENTS AND PROHIBITIONS UNDER PART 500 § 501.6 Cellulose sponges, irregular dimensions. Variety packages of cellulose sponges of irregular dimensions, are exempted from the requirements of § 500.25 of this...

  7. Composition for absorbing hydrogen

    DOEpatents

    Heung, L.K.; Wicks, G.G.; Enz, G.L.

    1995-05-02

    A hydrogen absorbing composition is described. The composition comprises a porous glass matrix, made by a sol-gel process, having a hydrogen-absorbing material dispersed throughout the matrix. A sol, made from tetraethyl orthosilicate, is mixed with a hydrogen-absorbing material and solidified to form a porous glass matrix with the hydrogen-absorbing material dispersed uniformly throughout the matrix. The glass matrix has pores large enough to allow gases having hydrogen to pass through the matrix, yet small enough to hold the particles dispersed within the matrix so that the hydrogen-absorbing particles are not released during repeated hydrogen absorption/desorption cycles.

  8. Composition for absorbing hydrogen

    DOEpatents

    Heung, Leung K.; Wicks, George G.; Enz, Glenn L.

    1995-01-01

    A hydrogen absorbing composition. The composition comprises a porous glass matrix, made by a sol-gel process, having a hydrogen-absorbing material dispersed throughout the matrix. A sol, made from tetraethyl orthosilicate, is mixed with a hydrogen-absorbing material and solidified to form a porous glass matrix with the hydrogen-absorbing material dispersed uniformly throughout the matrix. The glass matrix has pores large enough to allow gases having hydrogen to pass through the matrix, yet small enough to hold the particles dispersed within the matrix so that the hydrogen-absorbing particles are not released during repeated hydrogen absorption/desorption cycles.

  9. Think like a sponge: The genetic signal of sensory cells in sponges.

    PubMed

    Mah, Jasmine L; Leys, Sally P

    2017-11-01

    A complex genetic repertoire underlies the apparently simple body plan of sponges. Among the genes present in poriferans are those fundamental to the sensory and nervous systems of other animals. Sponges are dynamic and sensitive animals and it is intuitive to link these genes to behaviour. The proposal that ctenophores are the earliest diverging metazoan has led to the question of whether sponges possess a 'pre-nervous' system or have undergone nervous system loss. Both lines of thought generally assume that the last common ancestor of sponges and eumetazoans possessed the genetic modules that underlie sensory abilities. By corollary extant sponges may possess a sensory cell homologous to one present in the last common ancestor, a hypothesis that has been studied by gene expression. We have performed a meta-analysis of all gene expression studies published to date to explore whether gene expression is indicative of a feature's sensory function. In sponges we find that eumetazoan sensory-neural markers are not particularly expressed in structures with known sensory functions. Instead it is common for these genes to be expressed in cells with no known or uncharacterized sensory function. Indeed, many sensory-neural markers so far studied are expressed during development, perhaps because many are transcription factors. This suggests that the genetic signal of a sponge sensory cell is dissimilar enough to be unrecognizable when compared to a bilaterian sensory or neural cell. It is possible that sensory-neural markers have as yet unknown functions in sponge cells, such as assembling an immunological synapse in the larval globular cell. Furthermore, the expression of sensory-neural markers in non-sensory cells, such as adult and larval epithelial cells, suggest that these cells may have uncharacterized sensory functions. While this does not rule out the co-option of ancestral sensory modules in later evolving groups, a distinct genetic foundation may underlie the

  10. Facile synthesis of a two-tier hierarchical structured superhydrophobic-superoleophilic melamine sponge for rapid and efficient oil/water separation.

    PubMed

    Chen, Jiucun; You, Hui; Xu, Liqun; Li, Tianhao; Jiang, Xianquan; Li, Chang Ming

    2017-11-15

    Oil leakages often cause fatal disasters for environmental pollution but an efficient treatment of the oil spills is still very challenging. Sponge-substrates with superhydrophobicity and superoleophilicity have been attracted much attention for oil/water separation. In this study, an inexpensive commercial melamine sponge was chemically modified for the uses of oil spills treatment by oil/water separation. Inspiring from the superhydrophobic property of lotus leaf, pyrrole was polymerized by a simple vapor-phase deposition to encapsulate the raw melamine-formaldehyde (MF) sponge. The as-formed thin polypyrrole walls were utilized as reducing reagent to generate Ag nanoparticles on the capsuled sponge. Accordingly, a superhydrophobic melamine sponge with a two-tier hierarchical structure was achieved after fluorination, and this material was applied to absorb oil from water. The absorption capacity, absorption rate and recyclability were investigated. This superhydrophobic sponge exhibited an efficient and fast oil/water separation performance in complicated environment and could be applied in industrial production because of its low cost and simple fabrication procedure. This study presents a facile strategy for the fabrication of efficient oil sorbents based on a two-tier hierarchical structure, providing a novel means for the upgrading of engineered sorption materials. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Amino acid composition in determination of collagen origin and assessment of physical factors effects.

    PubMed

    Gauza-Włodarczyk, Marlena; Kubisz, Leszek; Włodarczyk, Dariusz

    2017-11-01

    The amino acid composition of collagen is a characteristic feature of this protein. Collagen, irrespective of its origin, contains 19 amino acids, including hydroxyproline which does not occur in other proteins. Its atypical amino acid composition is characterized by high content of proline and glycine, as well as the absence of cysteine. This paper shows the comparison of qualitative composition of amino acids of fish skin (FS) collagen, bovine Achilles tendon (BAT) collagen, and bone collagen. Results demonstrate that FS collagen as well as BAT collagen contains no cysteine and significantly different amount of hydroxyproline. In BAT collagen hydroxyproline content is 30% higher than hydroxyproline content of FS collagen. In bone collagen the amount of hydroxyproline is two times more than in FS collagen. Furthermore, it is shown that sensitivity to radiation of individual amino acids varies and depends on the absorbed dose of ionizing radiation. The changes observed in the amino acid composition become very intense for the doses of 500kGy and 1000kGy. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Collagen in organ development

    NASA Technical Reports Server (NTRS)

    Hardman, P.; Spooner, B. S.

    1992-01-01

    It is important to know whether microgravity will adversely affect developmental processes. Collagens are macromolecular structural components of the extracellular matrix (ECM) which may be altered by perturbations in gravity. Interstitial collagens have been shown to be necessary for normal growth and morphogenesis in some embryonic organs, and in the mouse salivary gland, the biosynthetic pattern of these molecules changes during development. Determination of the effects of microgravity on epithelial organ development must be preceded by crucial ground-based studies. These will define control of normal synthesis, secretion, and deposition of ECM macromolecules and the relationship of these processes to morphogenesis.

  13. Diversity and abundance of photosynthetic sponges in temperate Western Australia

    PubMed Central

    Lemloh, Marie-Louise; Fromont, Jane; Brümmer, Franz; Usher, Kayley M

    2009-01-01

    Background Photosynthetic sponges are important components of reef ecosystems around the world, but are poorly understood. It is often assumed that temperate regions have low diversity and abundance of photosynthetic sponges, but to date no studies have investigated this question. The aim of this study was to compare the percentages of photosynthetic sponges in temperate Western Australia (WA) with previously published data on tropical regions, and to determine the abundance and diversity of these associations in a range of temperate environments. Results We sampled sponges on 5 m belt transects to determine the percentage of photosynthetic sponges and identified at least one representative of each group of symbionts using 16S rDNA sequencing together with microscopy techniques. Our results demonstrate that photosynthetic sponges are abundant in temperate WA, with an average of 63% of sponge individuals hosting high levels of photosynthetic symbionts and 11% with low to medium levels. These percentages of photosynthetic sponges are comparable to those found on tropical reefs and may have important implications for ecosystem function on temperate reefs in other areas of the world. A diverse range of symbionts sometimes occurred within a small geographic area, including the three "big" cyanobacterial clades, Oscillatoria spongeliae, "Candidatus Synechococcus spongiarum" and Synechocystis species, and it appears that these clades all occur in a wide range of sponges. Additionally, spongin-permeating red algae occurred in at least 7 sponge species. This study provides the first investigation of the molecular phylogeny of rhodophyte symbionts in sponges. Conclusion Photosynthetic sponges are abundant and diverse in temperate WA, with comparable percentages of photosynthetic to non-photosynthetic sponges to tropical zones. It appears that there are three common generalist clades of cyanobacterial symbionts of sponges which occur in a wide range of sponges in a wide range

  14. Oxygen dynamics and transport in the Mediterranean sponge Aplysina aerophoba.

    PubMed

    Hoffmann, Friederike; Røy, Hans; Bayer, Kristina; Hentschel, Ute; Pfannkuchen, Martin; Brümmer, Franz; de Beer, Dirk

    2008-01-01

    The Mediterranean sponge Aplysina aerophoba kept in aquaria or cultivation tanks can stop pumping for several hours or even days. To investigate changes in the chemical microenvironments, we measured oxygen profiles over the surface and into the tissue of pumping and non-pumping A. aerophoba specimens with Clark-type oxygen microelectrodes (tip diameters 18-30 μm). Total oxygen consumption rates of whole sponges were measured in closed chambers. These rates were used to back-calculate the oxygen distribution in a finite-element model. Combining direct measurements with calculations of diffusive flux and modeling revealed that the tissue of non-pumping sponges turns anoxic within 15 min, with the exception of a 1 mm surface layer where oxygen intrudes due to molecular diffusion over the sponge surface. Molecular diffusion is the only transport mechanism for oxygen into non-pumping sponges, which allows total oxygen consumption rates of 6-12 μmol cm -3  sponge day -1 . Sponges of different sizes had similar diffusional uptake rates, which is explained by their similar surface/volume ratios. In pumping sponges, oxygen consumption rates were between 22 and 37 μmol cm -3  sponge day -1 , and the entire tissue was oxygenated. Combining different approaches of direct oxygen measurement in living sponges with a dynamic model, we can show that tissue anoxia is a direct function of the pumping behavior. The sponge-microbe system of A. aerophoba thus has the possibility to switch actively between aerobic and anaerobic metabolism by stopping the water flow for more than 15 min. These periods of anoxia will greatly influence physiological variety and activity of the sponge microbes. Detailed knowledge about the varying chemical microenvironments in sponges will help to develop protocols to cultivate sponge-associated microbial lineages and improve our understanding of the sponge-microbe-system.

  15. Sustainable use of marine resources: cultivation of sponges.

    PubMed

    Brümmer, F; Nickel, M

    2003-01-01

    Among all metazoan phyla, sponges are known to produce the largest number of bioactive compounds, some of them metabolites with human therapeutic value. Therefore, an increasing interest in basic cell biology research up to biochemical engineering can be observed aiming at the production of sponge metabolites under completely controlled conditions. One major obstacle is the limited availability of larger quantities of defined sponge material--the so-called supply problem. In this chapter, different approaches used so far for producing sponge biomass by in situ aquaculture as well as some significant progress in the maintenance of sponges in aquaria are reviewed. These approaches are mainly based on old methods for producing commercial bath sponges as well as on experience in maintaining sponges in public aquaria and on the usage of artificial substrates for a natural-like colonization structure. In recent years, great efforts have been made to set up in vitro culture systems for the cultivation of sponge cells. One of the major advantages of cell cultures is the possibility to control and manipulate the cultivation conditions depending on the sponge species and the target metabolite. Up to now, monolayer cultures of dissociated sponge cells have been shown in a few cases to produce the desired product. However, to date, no continuously growing sponge cell line has been established. Organotypic culture systems, which maintain or mimic the natural tissue structure, have been developed in recent years and demonstrate a promising way towards the biotechnology of sponges. Successful attempts to produce sponge metabolites using the three-dimensional growing primmorphs are given. The use of sponge fragments, another three-dimensional approach, has reappeared and has also been successfully used as an in vitro approach as well as for the biotechnological production of boreal sponge tissue.

  16. Fabrication of silver nanoparticle sponge leather with durable antibacterial property.

    PubMed

    Liu, Gongyan; Haiqi, Gao; Li, Kaijun; Xiang, Jun; Lan, Tianxiang; Zhang, Zongcai

    2018-03-15

    Leather product with durable antibacterial property is of great interest both from industry and consumer's point of view. To fabricate such functional leather, gallic acid modified silver nanoparticles (GA@AgNPs) were first in situ synthesized with a core-shell structure and an average size of 15.3nm. Due to its hydrophilic gallic acid surface, the GA@AgNPs possessed excellent stability and dispersibility in wide pH range from 3 to 12 and also showed effective antibacterial activity with a minimum inhibitory concentration (MIC) of around 10μgmL -1 . Then, such GA@AgNPs were used as retanning agent to be successfully filled into leather matrix during the leather manufacturing process. Moreover, taking the advantage of its high surface density of carboxyl groups, these GA@AgNPs could be further chemically cross-linked onto collagen fibers by chrome tanning agent. After retanning, the resultant leather was given a "AgNPs sponge" feature with high payload of silver nanoparticles against laundry, exhibiting high and durable antibacterial activity. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Stabilization and Anomalous Hydration of Collagen Fibril under Heating

    PubMed Central

    Gevorkian, Sasun G.; Allahverdyan, Armen E.; Gevorgyan, David S.; Simonian, Aleksandr L.; Hu, Chin-Kun

    2013-01-01

    Background Type I collagen is the most common protein among higher vertebrates. It forms the basis of fibrous connective tissues (tendon, chord, skin, bones) and ensures mechanical stability and strength of these tissues. It is known, however, that separate triple-helical collagen macromolecules are unstable at physiological temperatures. We want to understand the mechanism of collagen stability at the intermolecular level. To this end, we study the collagen fibril, an intermediate level in the collagen hierarchy between triple-helical macromolecule and tendon. Methodology/Principal Finding When heating a native fibril sample, its Young’s modulus decreases in temperature range 20–58°C due to partial denaturation of triple-helices, but it is approximately constant at 58–75°C, because of stabilization by inter-molecular interactions. The stabilization temperature range 58–75°C has two further important features: here the fibril absorbs water under heating and the internal friction displays a peak. We relate these experimental findings to restructuring of collagen triple-helices in fibril. A theoretical description of the experimental results is provided via a generalization of the standard Zimm-Bragg model for the helix-coil transition. It takes into account intermolecular interactions of collagen triple-helices in fibril and describes water adsorption via the Langmuir mechanism. Conclusion/Significance We uncovered an inter-molecular mechanism that stabilizes the fibril made of unstable collagen macromolecules. This mechanism can be relevant for explaining stability of collagen. PMID:24244320

  18. Preparation and evaluation of squid ink polysaccharide-chitosan as a wound-healing sponge.

    PubMed

    Huang, Na; Lin, Jiali; Li, Sidong; Deng, Yifeng; Kong, Songzhi; Hong, Pengzhi; Yang, Ping; Liao, Mingneng; Hu, Zhang

    2018-01-01

    A new type of wound healing agent was developed using two marine biomaterials (squid ink polysaccharide and chitosan) as carriers and calcium chloride as an initiator for coagulation. Based on central composite design-response surface methodology, comprehensive evaluation of appearance quality for composite sponges and water absorbency were used as evaluation indices to identify the optimized preparation conditions and further evaluate the performance of the squid ink polysaccharide-chitosan sponge (SIP-CS). The optimized formulation of SIP-CS was as follows: chitosan concentration, 2.29%; squid ink polysaccharide concentration, 0.55%; and calcium chloride concentration, 2.82%, at a volume ratio of 15:5:2. SIP-CS was conducive to sticking on the wound, characterized by the spongy property, strong absorptivity, and tackiness. Rabbit ear arterial, hepatic, and femoral artery hemorrhage experiments indicated that, compared with chitosan dressings and absorbable gelatin, the hemostatic times were shorter and the bleeding volume was smaller. Furthermore, SIP-CS absorbed a large amount of hemocytes, leading to rapid hemostasis. The healing areas and wound pathological sections in scalded New Zealand rabbits indicated that SIP-CS promoted wound healing more rapidly than chitosan and better than commercially available burn cream. Thus, SIP-CS is a good wound healing agent for rapid hemostasis, promoting burn/scalded skin healing, and protecting from wound infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. [The genetics of collagen diseases].

    PubMed

    Kaplan, J; Maroteaux, P; Frezal, J

    1986-01-01

    Heritable disorders of collagen include Ehler-Danlos syndromes (11 types are actually known), Larsen syndrome and osteogenesis imperfecta. Their clinical, genetic and biochemical features are reviewed. Marfan syndrome is closely related to heritable disorders of collagen.

  20. Sterilization of rotary NiTi instruments within endodontic sponges.

    PubMed

    Chan, H W A; Tan, K H; Dashper, S G; Reynolds, E C; Parashos, P

    2015-08-17

    To determine whether the following can be sterilized by autoclaving - endodontic sponges, rotary nickel-titanium (NiTi) instruments within endodontic sponges, and rotary NiTi instruments with rubber stoppers. Sixty-four samples of eight different endodontic sponges (n = 512) were placed into brain heart infusion broth (BHI) for 72 h. An aliquot of this was then spread onto horse blood agar and cultured aerobically and anaerobically to test sterility at purchase. Bacterial suspensions of Enterococcus faecalis, Porphyromonas gingivalis and Geobacillus stearothermophilus in BHI were used to contaminate sterile sponges and rotary NiTi instruments (with and without rubber stoppers) inserted into sponges. The various samples were autoclaved and then cultured aerobically and anaerobically. Success of sterilization was measured qualitatively as no growth. The experiment was repeated with clinically used rotary NiTi instruments (n = 512). All experiments were conducted in quadruplicate. No sponges on purchase had microbial growth when anaerobically cultured but some did when aerobically cultured. All autoclaved sponges and instruments (within or without sponges, and with or without rubber stoppers) were associated with no microbial growth. All nonautoclaved positive control samples showed microbial growth. Autoclaving was effective in the sterilization of sponges and endodontic instruments. Endodontic sponges should be autoclaved before clinical use. For clinical efficiency and cost-effectiveness, rotary NiTi instruments can be sterilized in endodontic sponges without removal of rubber stoppers. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  1. Externally tuned vibration absorber

    DOEpatents

    Vincent, Ronald J.

    1987-09-22

    A vibration absorber unit or units are mounted on the exterior housing of a hydraulic drive system of the type that is powered from a pressure wave generated, e.g., by a Stirling engine. The hydraulic drive system employs a piston which is hydraulically driven to oscillate in a direction perpendicular to the axis of the hydraulic drive system. The vibration absorbers each include a spring or other resilient member having one side affixed to the housing and another side to which an absorber mass is affixed. In a preferred embodiment, a pair of vibration absorbers is employed, each absorber being formed of a pair of leaf spring assemblies, between which the absorber mass is suspended.

  2. Methods for absorbing neutrons

    DOEpatents

    Guillen, Donna P [Idaho Falls, ID; Longhurst, Glen R [Idaho Falls, ID; Porter, Douglas L [Idaho Falls, ID; Parry, James R [Idaho Falls, ID

    2012-07-24

    A conduction cooled neutron absorber may include a metal matrix composite that comprises a metal having a thermal neutron cross-section of at least about 50 barns and a metal having a thermal conductivity of at least about 1 W/cmK. Apparatus for providing a neutron flux having a high fast-to-thermal neutron ratio may include a source of neutrons that produces fast neutrons and thermal neutrons. A neutron absorber positioned adjacent the neutron source absorbs at least some of the thermal neutrons so that a region adjacent the neutron absorber has a fast-to-thermal neutron ratio of at least about 15. A coolant in thermal contact with the neutron absorber removes heat from the neutron absorber.

  3. An evaluation of sterilization of endodontic instruments in artificial sponges.

    PubMed

    Vélez, A E; Thomas, D D; del Río, C E

    1998-01-01

    The ability to sterilize endodontic files inserted into synthetic sponges was tested. Sponges were subjected to 5 cycles of either dry heat (Driclave) or steam under pressure (autoclave) sterilization. Sterilization was corroborated by microbiological tests. The sponges and files were pre-sterilized separately using steam under pressure. One hundred eighty files contaminated with Bacillus stearothermophilus spores (experimental and positive control) and 60 noncontaminated files (negative control), were inserted into 60 sponges. After each cycle, each file and a portion of sponge surrounding the file were transferred aseptically to tubes containing trypticase soy broth culture medium for bacteriological analysis. None of the tubes containing files and portions of sponges that were subjected to autoclave grew Bacillus stearothermophilus spores. Two of 60 (3.33%) of the tubes that were subjected to sterilization by Driclave demonstrated bacterial growth. Although the sponges tolerated the dry heat cycles well physically, sterilization was achieved in only 96.67% of the cases.

  4. Sheep antibodies to soluble rat collagen

    PubMed Central

    Chidlow, J. W.; Bourne, F. J.; Bailey, A. J.

    1974-01-01

    Sheep were immunized by multiple injections of acid-extracted rat tail tendon tropocollagen. Antibody activity could be demonstrated by quantitative precipitation and passive haemagglutination against denatured tropocollagen. Immunodiffusion experiments showed strong precipitin lines with denatured tendon tropocollagen, and with peptides obtained by CNBr digestion of whole rat tail tendon. Immunoelectrophoresis showed one line with denatured tropocollagen but four lines with the CNBr digest of whole tendon indicating at least four antigenic determinants. Immunosorbents prepared from antisera raised against tropocollagen readily absorbed labelled peptides from CNBr digests of rat tail tendons reduced with tritiated borohydride. These peptides were recoverable by desorption with 1 M ammonia and had a hydroxyproline and hydroxylysine content typical of collagen but increased tyrosine levels. Presence of the normal reducible components of collagen known to be involved in cross-linking was confirmed by ion-exchange chromatography, and there was an increase in the proportion of fraction C. The majority of the tritium label was found in a cross-linked peptide, or group of peptides, with molecular weight around 60,000. The technique therefore has the potential for further development in the isolation of specific collagen peptides. ImagesFIG. 3FIG. 4 PMID:4140151

  5. Collagen hydrolysate based collagen/hydroxyapatite composite materials

    NASA Astrophysics Data System (ADS)

    Ficai, Anton; Albu, Madalina Georgiana; Birsan, Mihaela; Sonmez, Maria; Ficai, Denisa; Trandafir, Viorica; Andronescu, Ecaterina

    2013-04-01

    The aim of this study was to study the influence of collagen hydrolysate (HAS) on the formation of ternary collagen-hydrolysate/hydroxyapatite composite materials (COLL-HAS/HA). During the precipitation process of HA, a large amount of brushite is resulted at pH = 7 but, practically pure HA is obtained at pH ⩾ 8. The FTIR data reveal the duplication of the most important collagen absorption bands due to the presence of the collagen hydrolysate. The presence of collagen hydrolysate is beneficial for the management of bone and joint disorders such as osteoarthritis and osteoporosis.

  6. Changes in denaturation and rheological properties of collagen-hyaluronic acid scaffolds as a result of temperature dependencies.

    PubMed

    Pietrucha, Krystyna

    2005-09-28

    This report describes the effect of temperature on the mechanical viscoelastic properties such as: storage modulus (E'), loss modulus (E''), and loss tangent (tandelta) of the collagen sponges modified with hyaluronic acid (HA). In order to detect collagen-HA copolymer denaturation and to assess its thermal stability, the differential scanning calorimetry (DSC) supplemented by thermogravimetric (TG) measurements was used. The denaturation temperature (T(d)) of unmodified collagen samples increased from 69 to 86 degrees C for cross-linked samples, respectively. These temperature dependencies show remarkable changes in E' and E'' at selected temperature up to 226 degrees C for all samples due to the release of loosely and strongly bound water. The influence of HA on the viscoelastic behavior of collagen is manifested by a shift of the tandelta peak associated with the process of decomposition towards higher temperatures resulting in a higher thermo-stability of the modified scaffolds.

  7. Benzene derivatives from the marine sponges Cinachyrella

    NASA Astrophysics Data System (ADS)

    Abraham; Syah, Y. M.; Natsir, H.; Hariani Soekamto, Nunuk

    2018-03-01

    The benzene derivatives from the Spermonde Archipelago sponges Cinachyrella was isolated. 4-hydroxy-benzenepropanoic acid (1) from Cinachyrella australiensis, 4-methyl- benzoic acid (2) and 4-hydroxy-benzonitrile (3) from Cinachyrella sp. The structues of 1, 2, and 3 have been determined by 1H-NMR, 13C-NMR, and HR-MS.

  8. Differential expression of type X collagen in a mechanically active 3-D chondrocyte culture system: a quantitative study

    PubMed Central

    Yang, Xu; Vezeridis, Peter S; Nicholas, Brian; Crisco, Joseph J; Moore, Douglas C; Chen, Qian

    2006-01-01

    Objective Mechanical loading of cartilage influences chondrocyte metabolism and gene expression. The gene encoding type X collagen is expressed specifically by hypertrophic chondrocytes and up regulated during osteoarthritis. In this study we tested the hypothesis that the mechanical microenvironment resulting from higher levels of local strain in a three dimensional cell culture construct would lead to an increase in the expression of type X collagen mRNA by chondrocytes in those areas. Methods Hypertrophic chondrocytes were isolated from embryonic chick sterna and seeded onto rectangular Gelfoam sponges. Seeded sponges were subjected to various levels of cyclic uniaxial tensile strains at 1 Hz with the computer-controlled Bio-Stretch system. Strain distribution across the sponge was quantified by digital image analysis. After mechanical loading, sponges were cut and the end and center regions were separated according to construct strain distribution. Total RNA was extracted from the cells harvested from these regions, and real-time quantitative RT-PCR was performed to quantify mRNA levels for type X collagen and a housing-keeping gene 18S RNA. Results Chondrocytes distributed in high (9%) local strain areas produced more than two times type X collagen mRNA compared to the those under no load conditions, while chondrocytes located in low (2.5%) local strain areas had no appreciable difference in type X collagen mRNA production in comparison to non-loaded samples. Increasing local strains above 2.5%, either in the center or end regions of the sponge, resulted in increased expression of Col X mRNA by chondrocytes in that region. Conclusion These findings suggest that the threshold of chondrocyte sensitivity to inducing type X collagen mRNA production is more than 2.5% local strain, and that increased local strains above the threshold results in an increase of Col X mRNA expression. Such quantitative analysis has important implications for our understanding of

  9. Collagen esterification enhances the function and survival of pancreatic β cells in 2D and 3D culture systems

    SciTech Connect

    Ko, Jae Hyung; Kim, Yang Hee; Asan Institute for Life Science, 388-1 Pungnap-2 Dong, Songpa-gu, Seoul

    Collagen, one of the most important components of the extracellular matrix (ECM), may play a role in the survival of pancreatic islet cells. In addition, chemical modifications that change the collagen charge profile to a net positive charge by esterification have been shown to increase the adhesion and proliferation of various cell types. The purpose of this study was to characterize and compare the effects of native collagen (NC) and esterified collagen (EC) on β cell function and survival. After isolation by the collagenase digestion technique, rat islets were cultured with NC and EC in 2 dimensional (2D) and 3more » dimensional (3D) environments for a long-term duration in vitro. The cells were assessed for islet adhesion, morphology, viability, glucose-induced insulin secretion, and mRNA expression of glucose metabolism-related genes, and visualized by scanning electron microscopy (SEM). Islet cells attached tightly in the NC group, but islet cell viability was similar in both the NC and EC groups. Glucose-stimulated insulin secretion was higher in the EC group than in the NC group in both 2D and 3D culture. Furthermore, the mRNA expression levels of glucokinase in the EC group were higher than those in the NC group and were associated with glucose metabolism and insulin secretion. Finally, SEM observation confirmed that islets had more intact component cells on EC sponges than on NC sponges. These results indicate that modification of collagen may offer opportunities to improve function and viability of islet cells. - Highlights: • We changed the collagen charge profile to a net positive charge by esterification. • Islets cultured on esterified collagen improved survival in both 2D and 3D culture. • Islets cultured on esterified collagen enhanced glucose-stimulated insulin release. • High levels of glucokinase mRNA may be associated with increased insulin release.« less

  10. Antiviral lead compounds from marine sponges.

    PubMed

    Sagar, Sunil; Kaur, Mandeep; Minneman, Kenneth P

    2010-10-11

    Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hoped to be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed.

  11. Advanced neutron absorber materials

    DOEpatents

    Branagan, Daniel J.; Smolik, Galen R.

    2000-01-01

    A neutron absorbing material and method utilizing rare earth elements such as gadolinium, europium and samarium to form metallic glasses and/or noble base nano/microcrystalline materials, the neutron absorbing material having a combination of superior neutron capture cross sections coupled with enhanced resistance to corrosion, oxidation and leaching.

  12. Rheology of heterotypic collagen networks.

    PubMed

    Piechocka, Izabela K; van Oosten, Anne S G; Breuls, Roel G M; Koenderink, Gijsje H

    2011-07-11

    Collagen fibrils are the main structural element of connective tissues. In many tissues, these fibrils contain two fibrillar collagens (types I and V) in a ratio that changes during tissue development, regeneration, and various diseases. Here we investigate the influence of collagen composition on the structure and rheology of networks of purified collagen I and V, combining fluorescence and atomic force microscopy, turbidimetry, and rheometry. We demonstrate that the network stiffness strongly decreases with increasing collagen V content, even though the network structure does not substantially change. We compare the rheological data with theoretical models for rigid polymers and find that the elasticity is dominated by nonaffine deformations. There is no analytical theory describing this regime, hampering a quantitative interpretation of the influence of collagen V. Our findings are relevant for understanding molecular origins of tissue biomechanics and for guiding rational design of collagenous biomaterials for biomedical applications.

  13. Characterizing the sponge grounds of Grays Canyon, Washington, USA

    USGS Publications Warehouse

    Powell, Abby N.; Clarke, M. Elizabeth; Fruh, Erica; Chaytor, Jason; Reiswig, Henry M.; Whitmire, Curt E.

    2018-01-01

    Deep-sea sponge grounds are relatively understudied ecosystems that may provide key habitats for a large number of fish and invertebrates including commercial species. Glass sponge grounds have been discovered from the tropics to polar regions but there are only a few places with high densities of dictyonine sponges. Dictyonine glass sponges have a fused skeleton, which stays intact when they die and in some areas the accumulation of successive generations of sponges leads to the formation of reefs. In 2010 and 2016, we surveyed an area near Grays Canyon in Washington, USA, where dense aggregations of glass sponges and potential sponge reefs were discovered in 2007. Our primary aims were to make a preliminary assessment of whether the glass sponges form reefs at this location, characterize the sponge assemblage present at this site and examine associations between the sponges and commercially important species. Multibeam mapping and sub-bottom profiling indicate that the glass sponges at this site do not form reefs and are mostly attached to hard substrates. Analysis of photographs collected by an autonomous underwater vehicle and samples collected by a remotely operated vehicle guided by telepresence revealed the presence of two abundant dictyonine sponge species at this site, Heterochone calyx and Aphrocallistes vastus (mean densities = 1.43 ± 0.057 per 10 m2, max = 24 per 10 m2). We also observed a large number of non-reef-building glass sponges and various demosponges including a potentially new species in the genus Acarnus. A diverse fish assemblage was recorded at this site including eight species of rockfish. Rockfish abundance was positively related to sponge abundance. Spot prawns (Pandalus platyceros) were also abundant and were strongly associated with sponges. Despite not finding sponge reefs, this is an ecologically significant area. Further research is necessary to determine the environmental factors that give rise to the abundance of large

  14. Sponge-Associated Microorganisms: Evolution, Ecology, and Biotechnological Potential†

    PubMed Central

    Taylor, Michael W.; Radax, Regina; Steger, Doris; Wagner, Michael

    2007-01-01

    Summary: Marine sponges often contain diverse and abundant microbial communities, including bacteria, archaea, microalgae, and fungi. In some cases, these microbial associates comprise as much as 40% of the sponge volume and can contribute significantly to host metabolism (e.g., via photosynthesis or nitrogen fixation). We review in detail the diversity of microbes associated with sponges, including extensive 16S rRNA-based phylogenetic analyses which support the previously suggested existence of a sponge-specific microbiota. These analyses provide a suitable vantage point from which to consider the potential evolutionary and ecological ramifications of these widespread, sponge-specific microorganisms. Subsequently, we examine the ecology of sponge-microbe associations, including the establishment and maintenance of these sometimes intimate partnerships, the varied nature of the interactions (ranging from mutualism to host-pathogen relationships), and the broad-scale patterns of symbiont distribution. The ecological and evolutionary importance of sponge-microbe associations is mirrored by their enormous biotechnological potential: marine sponges are among the animal kingdom's most prolific producers of bioactive metabolites, and in at least some cases, the compounds are of microbial rather than sponge origin. We review the status of this important field, outlining the various approaches (e.g., cultivation, cell separation, and metagenomics) which have been employed to access the chemical wealth of sponge-microbe associations. PMID:17554047

  15. Epizoic zoanthids reduce pumping in two Caribbean vase sponges

    NASA Astrophysics Data System (ADS)

    Lewis, T. B.; Finelli, C. M.

    2015-03-01

    Sponges are common sessile benthic suspension feeders that play a critical role in carbon and nitrogen cycling within reef ecosystems via their filtration capabilities. Due to the contribution of sponges in benthic-pelagic coupling, it is critical to assess factors that may affect their role in the healthy function of coral reefs. Several factors can influence the rate at which an individual sponge pumps water, including body size, environmental conditions, mechanical blockage, and reduction of inhalant pores (ostia). Symbiotic zoanthid colonization is a common occurrence on Caribbean sponges, and the presence of zoanthids on the surface of a sponge may occlude or displace the inhalant ostia. We quantified pumping rates of the giant barrel sponge, Xestospongia muta ( N = 22 uncolonized, 37 colonized) and the common vase sponge, Niphates digitalis ( N = 21 uncolonized, 17 colonized), with and without zoanthid symbionts, Parazoanthus catenularis and Parazoanthus parasiticus, respectively. For X. muta, biovolume-normalized pumping rates of individuals colonized by zoanthids were approximately 75 % lower than those of uncolonized sponges. Moreover, colonization with zoanthids was related to a difference in morphology relative to uncolonized individuals: Colonized sponges exhibited an osculum area to biovolume ratio that was nearly 65 % less than uncolonized sponges. In contrast, the presence of zoanthids on N. digitalis resulted in only a marginal decrease in pumping rates and no detectable difference in morphology. The difference in zoanthid effects between X. muta and N. digitalis is likely due to the differences in wall thickness and architecture between the two species. The probable cause of reduced pumping in affected sponges is occupation of the sponge surface that leads to blockage or displacement of inhalant ostia. To partially test this hypothesis, zoanthid colonization on specimens of X. muta was simulated by wrapping sponges with plastic mesh of varying

  16. Internal absorber solar collector

    DOEpatents

    Sletten, Carlyle J.; Herskovitz, Sheldon B.; Holt, F. S.; Sletten, E. J.

    1981-01-01

    Thin solar collecting panels are described made from arrays of small rod collectors consisting of a refracting dielectric rod lens with an absorber imbedded within it and a reflecting mirror coated on the back side of the dielectric rod. Non-tracking collector panels on vertical walls or roof tops receive approximately 90% of solar radiation within an acceptance zone 60.degree. in elevation angle by 120.degree. or more in the azimuth sectors with a collector concentration ratio of approximately 3.0. Miniaturized construction of the circular dielectric rods with internal absorbers reduces the weight per area of glass, plastic and metal used in the collector panels. No external parts or insulation are needed as heat losses are low due to partial vacuum or low conductivity gas surrounding heated portions of the collector. The miniature internal absorbers are generally made of solid copper with black selective surface and the collected solar heat is extracted at the collector ends by thermal conductivity along the absorber rods. Heat is removed from end fittings by use of liquid circulants. Several alternate constructions are provided for simplifying collector panel fabrication and for preventing the thermal expansion and contraction of the heated absorber or circulant tubes from damaging vacuum seals. In a modified version of the internal absorber collector, oil with temperature dependent viscosity is pumped through a segmented absorber which is now composed of closely spaced insulated metal tubes. In this way the circulant is automatically diverted through heated portions of the absorber giving higher collector concentration ratios than theoretically possible for an unsegmented absorber.

  17. Lipid-absorbing Polymers

    NASA Technical Reports Server (NTRS)

    Marsh, H. E., Jr.; Wallace, C. J.

    1973-01-01

    The removal of bile acids and cholesterol by polymeric absorption is discussed in terms of micelle-polymer interaction. The results obtained with a polymer composed of 75 parts PEO and 25 parts PB plus curing ingredients show an absorption of 305 to 309%, based on original polymer weight. Particle size effects on absorption rate are analyzed. It is concluded that crosslinked polyethylene oxide polymers will absorb water, crosslinked polybutadiene polymers will absorb lipids; neither polymer will absorb appreciable amounts of lipids from micellar solutions of lipids in water.

  18. Impact absorption properties of carbon fiber reinforced bucky sponges

    NASA Astrophysics Data System (ADS)

    Thevamaran, Ramathasan; Saini, Deepika; Karakaya, Mehmet; Zhu, Jingyi; Podila, Ramakrishna; Rao, Apparao M.; Daraio, Chiara

    2017-05-01

    We describe the super compressible and highly recoverable response of bucky sponges as they are struck by a heavy flat-punch striker. The bucky sponges studied here are structurally stable, self-assembled mixtures of multiwalled carbon nanotubes (MWCNTs) and carbon fibers (CFs). We engineered the microstructure of the sponges by controlling their porosity using different CF contents. Their mechanical properties and energy dissipation characteristics during impact loading are presented as a function of their composition. The inclusion of CFs improves the impact force damping by up to 50% and the specific damping capacity by up to 7% compared to bucky sponges without CFs. The sponges also exhibit significantly better stress mitigation characteristics compared to vertically aligned CNT foams of similar densities. We show that delamination occurs at the MWCNT-CF interfaces during unloading, and it arises from the heterogeneous fibrous microstructure of the bucky sponges.

  19. Ultraporous, Compressible, Wettable Polylactide/Polycaprolactone Sponges for Tissue Engineering.

    PubMed

    Mader, Michael; Jérôme, Valérie; Freitag, Ruth; Agarwal, Seema; Greiner, Andreas

    2018-05-14

    Ultraporous, degradable sponges made of either polylactide or of blends of polylactide/poly(ε-caprolactone) are prepared by freeze-drying of dispersions of short electrospun fibers and subsequent thermal annealing. The sponges feature ultrahigh porosity (99.6%), a hierarchical cellular structure, and high reversible compressibility with fast recovery from deformation in the dry as well as in the wet state. The sponge properties depend on the fiber dispersion concentration and the annealing temperature. Sponge characteristics like fiber density (2.5-20 mg/cm 3 ), size, shape, crystallinity, mechanical strength, wetability, and structural integrity are user adjustable. Cell culture experiments were successfully performed with Jurkat cells with Confocal Laser Scanning Microscopy and MTT staining showing rapid cell proliferation. Live/Dead staining demonstrated high viability of the seeded cells. The sponge characteristics and modifications investigated and presented here reveal that these sponges are highly promising for tissue engineering applications.

  20. Modeling the Distribution of Geodia Sponges and Sponge Grounds in the Northwest Atlantic

    PubMed Central

    Knudby, Anders; Kenchington, Ellen; Murillo, Francisco Javier

    2013-01-01

    Deep-sea sponge grounds provide structurally complex habitat for fish and invertebrates and enhance local biodiversity. They are also vulnerable to bottom-contact fisheries and prime candidates for Vulnerable Marine Ecosystem designation and related conservation action. This study uses species distribution modeling, based on presence and absence observations of Geodia spp. and sponge grounds derived from research trawl catches, as well as spatially continuous data on the physical and biological ocean environment derived from satellite data and oceanographic models, to model the distribution of Geodia sponges and sponge grounds in the Northwest Atlantic. Most models produce excellent fits with validation data although fits are reduced when models are extrapolated to new areas, especially when oceanographic regimes differ between areas. Depth and minimum bottom salinity were important predictors in most models, and a Geodia spp. minimum bottom salinity tolerance threshold in the 34.3-34.8 psu range was hypothesized on the basis of model structure. The models indicated two currently unsampled regions within the study area, the deeper parts of Baffin Bay and the Newfoundland and Labrador slopes, where future sponge grounds are most likely to be found. PMID:24324768

  1. Deep phylogeny and evolution of sponges (phylum Porifera).

    PubMed

    Wörheide, G; Dohrmann, M; Erpenbeck, D; Larroux, C; Maldonado, M; Voigt, O; Borchiellini, C; Lavrov, D V

    2012-01-01

    Sponges (phylum Porifera) are a diverse taxon of benthic aquatic animals of great ecological, commercial, and biopharmaceutical importance. They are arguably the earliest-branching metazoan taxon, and therefore, they have great significance in the reconstruction of early metazoan evolution. Yet, the phylogeny and systematics of sponges are to some extent still unresolved, and there is an on-going debate about the exact branching pattern of their main clades and their relationships to the other non-bilaterian animals. Here, we review the current state of the deep phylogeny of sponges. Several studies have suggested that sponges are paraphyletic. However, based on recent phylogenomic analyses, we suggest that the phylum Porifera could well be monophyletic, in accordance with cladistic analyses based on morphology. This finding has many implications for the evolutionary interpretation of early animal traits and sponge development. We further review the contribution that mitochondrial genes and genomes have made to sponge phylogenetics and explore the current state of the molecular phylogenies of the four main sponge lineages (Classes), that is, Demospongiae, Hexactinellida, Calcarea, and Homoscleromorpha, in detail. While classical systematic systems are largely congruent with molecular phylogenies in the class Hexactinellida and in certain parts of Demospongiae and Homoscleromorpha, the high degree of incongruence in the class Calcarea still represents a challenge. We highlight future areas of research to fill existing gaps in our knowledge. By reviewing sponge development in an evolutionary and phylogenetic context, we support previous suggestions that sponge larvae share traits and complexity with eumetazoans and that the simple sedentary adult lifestyle of sponges probably reflects some degree of secondary simplification. In summary, while deep sponge phylogenetics has made many advances in the past years, considerable efforts are still required to achieve a

  2. Ridge preservation of extraction sockets with chronic pathology using Bio-Oss® Collagen with or without collagen membrane: an experimental study in dogs.

    PubMed

    Kim, Jung-Ju; Schwarz, Frank; Song, Hyun Young; Choi, YoonMi; Kang, Kyung-Rim; Koo, Ki-Tae

    2017-06-01

    This study aimed to evaluate the dynamics of newly bone formation and dimensional change in diseased extraction sockets using Bio-Oss ® Collagen with or without a collagen membrane. In six beagle dogs, right and left 3rd and 4th mandibular premolars were hemisected and the distal roots were removed. Combined endodontic-periodontic lesions were induced in all sites using black silk, collagen sponge, endodontic files, and application of Porphyromonas gingivalis. After 4 months, among 4 premolars, three teeth were randomly selected per dog and allocated to the following experimental groups: Control group (no treatment but debridement), Test 1 group (only Bio-Oss ® Collagen graft), and Test 2 group (Bio-Oss ® Collagen graft with a collagen membrane). After 7 months from the baseline, the beagle dogs were sacrificed for histomorphometric and Micro-CT analysis. The vertical distance between buccal and lingual crests in the Control group (2.22 ± 0.26 mm) and Test 2 group (1.80 ± 0.16 mm) was significantly different. The socket of the Test 2 group (27.04 ± 5.25%) was occupied by a greater quantity of bone graft compared to the Test 1 group (18.49 ± 2.11%). Ridge preservation in diseased extraction sockets could compensate for buccal bone resorption by contact osteogenesis surrounding the bone graft particles at the bucco-coronal area during socket healing, and the application of a collagen membrane at the entrance of the socket is useful for preserving graft material at the coronal part of the socket. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Re-plumbing in a Mediterranean sponge.

    PubMed

    Mendola, D; van den Boogaart, J G M; van Leeuwen, J L; Wijffels, R H

    2007-12-22

    Observations are reported for Dysidea avara sponges where once functioning oscula (outlets) are converted through internal re-plumbing into functioning oversized ostia (OSO; inlets). Flow tank studies employed high-speed photography and particle tracking of laser-illuminated 0.5-6.0 microm diameter glass beads to trace particles streaming into OSO. A fluorescein dye/glass bead uptake experiment showed that an oversized ostium was connected through internal structures to the lone osculum. Beginning 30 s after uptake and continuing over a 20 min period, dye streamed from the osculum, but no beads emerged. Scanning electron microscopy revealed that beads were deposited only on the inhalant side of particle filtering choanocyte chambers and not on the exhalant side, suggesting that internal re-plumbing had occurred. Functioning OSO were also found on freshly collected specimens in the field, making it highly unlikely that formation of OSO was only an artefact of sponges being held in a laboratory tank.

  4. "Smart" Electromechanical Shock Absorber

    NASA Technical Reports Server (NTRS)

    Stokes, Lebarian; Glenn, Dean C.; Carroll, Monty B.

    1989-01-01

    Shock-absorbing apparatus includes electromechanical actuator and digital feedback control circuitry rather than springs and hydraulic damping as in conventional shock absorbers. Device not subject to leakage and requires little or no maintenance. Attenuator parameters adjusted in response to sensory feedback and predictive algorithms to obtain desired damping characteristic. Device programmed to decelerate slowly approaching vehicle or other large object according to prescribed damping characteristic.

  5. Tactile texture and friction of soft sponge surfaces.

    PubMed

    Takahashi, Akira; Suzuki, Makoto; Imai, Yumi; Nonomura, Yoshimune

    2015-06-01

    We evaluated the tactile texture and frictional properties of five soft sponges with various cell sizes. The frictional forces were measured by a friction meter containing a contact probe with human-finger-like geometry and mechanical properties. When the subjects touched these sponges with their fingers, hard-textured sponges were deemed unpleasant. This tactile feeling changed with friction factors including friction coefficients, their temporal patterns, as well as mechanical and shape factors. These findings provide useful information on how to control the tactile textures of various sponges. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Bacteria From Marine Sponges: A Source of New Drugs.

    PubMed

    Bibi, Fehmida; Faheem, Muhammad; Azhar, Esam I; Yasir, Muhammad; Alvi, Sana A; Kamal, Mohammad A; Ullah, Ikram; Naseer, Muhammad I

    2017-01-01

    Sponges are rich source of bioactive natural products synthesized by the symbiotic bacteria belonging to different phyla. Due to a competition for space and nutrients the marine bacteria associated with sponges could produce more antibiotic substances. To explore the proactive potential of marine microbes extensive research has been done. These bioactive metabolites have some unique properties that are pharmaceutically important. For this review, we have performed a non-systematic search of the available literature though various online search engines. This review provides an insight that how majority of active metabolites have been identified from marine invertebrates of which sponges predominate. Sponges harbor abundant and diverse microorganisms, which are the sources of a range of marine bioactive metabolites. From sponges and their associated microorganisms, approximately 5,300 different natural compounds are known. Current research on sponge-microbe interaction and their active metabolites has become a focal point for many researchers. Various active metabolites derived from sponges are now known to be produced by their symbiotic microflora. In this review, we attempt to report the latest studies regarding capability of bacteria from sponges as producers of bioactive metabolite. Moreover, these sponge associated bacteria are an important source of different enzymes of industrial significance. In present review, we will address some novel approaches for discovering marine metabolites from bacteria that have the greatest potential to be used in clinical treatments. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  7. Deciphering Galactic Hydrogen with 21-SPONGE

    NASA Astrophysics Data System (ADS)

    Murray, Claire; Stanimirovic, Snezana; Goss, Miller; Heiles, Carl E.; Miller Dickey, John; Lindner, Robert; Babler, Brian L.

    2017-01-01

    Neutral hydrogen (HI) in the interstellar medium (ISM) is crucial to the life cycles of galaxies. The balance between disparate phases of HI -- including the cold neutral (CNM) and warm neutral (WNM) medium -- governs the formation of dense, star-forming material, and reflects the nature of feedback in galaxies. To probe the multi-phase structure of HI, we present results from 21-SPONGE: the largest and most sensitive survey for Galactic HI absorption ever at the Karl G. Jansky Very Large Array (VLA). Complemented by HI emission from the Arecibo Observatory, 21-SPONGE is uniquely sensitive to CNM and WNM temperatures from 10-104 K and column densities from 1018-1022 cm-2. Despite our unprecedented sensitivity, the maximum temperature we detect for individual spectral lines is Ts~1500 K, although stacking analysis of 21-SPONGE absorption lines indicates the presence of pervasive, high-Ts WNM population with Ts~7000 K. To understand the physics underlying these results, we developed Autonomous Gaussian Decomposition (AGD), a Python-based tool for efficiently and objectively analyzing spectral lines. By applying AGD to 21-SPONGE and 1000s of synthetic HI spectra from 3D numerical simulations, we correct our measurements for completeness and observational biases. We further prove that we can successfully recover the temperatures and densities of real clouds along simulated lines of sight. In addition, we show that absorption line shapes are sensitive to the strength and topology of the Lyman alpha radiation field and its role in HI excitation, which are poorly-constrained yet important for understanding the energy balance of the ISM. Our results are among the first to statistically quantify the success of observational methods at reproducing true HI properties, and represent crucial steps towards understanding the role of HI in star formation.

  8. Optimization of biodegradable sponges as controlled release drug matrices. I. Effect of moisture level on chitosan sponge mechanical properties.

    PubMed

    Foda, Nagwa H; El-laithy, Hanan M; Tadros, Mina I

    2004-04-01

    Cross-linked chitosan sponges as controlled release drug carrier systems were developed. Tramadol hydrochloride, a centrally acting analgesic, was used as a model drug. The sponges were prepared by freeze-drying 1.25% and 2.5% (w/w) high and low M.wt. chitosan solutions, respectively, using glutaraldehyde as a cross-linking agent. The hardness of the prepared sponges was a function of glutaraldehyde concentration and volume where the optimum concentration that offered accepted sponge consistency was 5%. Below or above 5%, very soft or very hard and brittle sponges were obtained, respectively. The determined drug content in the prepared sponges was uniform and did not deviate markedly from the calculated amount. Scanning electron microscopy (SEM) was used to characterize the internal structures of the sponges. The SEM photos revealed that cross-linked high M.wt. chitosan sponges have larger size surface pores that form connections (channels) with the interior of the sponge than cross-linked low M.wt. ones. Moreover, crystals of the incorporated Tramadol hydrochloride were detected on the lamellae and within pores in both chitosan sponges. Differences in pore size and dissolution medium uptake capacity were crucial factors for the more delayed drug release from cross-linked low M.wt. chitosan sponges over high M.wt. ones at pH 7.4. Kinetic analysis of the release data using linear regression followed the Higuchi diffusion model over 12 hours. Setting storage conditions at room temperature under 80-92% relative humidity resulted in soft, elastic, and compressible sponges.

  9. A tissue engineering approach for prenatal closure of myelomeningocele: comparison of gelatin sponge and microsphere scaffolds and bioactive protein coatings.

    PubMed

    Watanabe, Miho; Li, Hiaying; Roybal, Jessica; Santore, Matthew; Radu, Antonetta; Jo, Jun-Ichiro; Kaneko, Michio; Tabata, Yasuhiko; Flake, Alan

    2011-04-01

    Myelomeningocele (MMC) is a common and devastating malformation. As an alternative to fetal surgical repair, tissue engineering has the potential to provide a less invasive approach for tissue coverage applicable at an earlier stage of gestation. We have previously evaluated the use of gelatin hydrogel composites composed of gelatin sponges and sheets as a platform for tissue coverage of the MMC defect in the retinoic acid induced fetal rat model of MMC. In the current study, we compare our previous composite with gelatin microspheres as a scaffold for tissue ingrowth and cellular adhesion within the amniotic fluid environment. We also examine the relative efficacy of various bioactive protein coatings on the adhesion of amniotic fluid cells to the construct within the amniotic cavity. We conclude from this study that gelatin microspheres are as effective as gelatin sponges as a scaffold for cellular ingrowth and amniotic fluid cell adhesion and that collagen type I and fibronectin coatings enhance amniotic fluid cell adhesion to the gelatin-based scaffolds. These findings support the potential for the development of a tissue-engineered injectable scaffold that could be applied by ultrasound-guided injection, much earlier and less invasively than sponge or sheet-based composites.

  10. Phagocytosis of sperm by follicle cells of the carnivorous sponge Asbestopluma occidentalis (Porifera, Demospongiae).

    PubMed

    Riesgo, Ana

    2010-06-01

    During spermatogenesis of the carnivorous sponge Asbestopluma occidentalis, follicle cells that lined the spermatocysts phagocytosed unreleased mature sperm. Such follicle cells are part of the complex envelope that limits spermatocysts of A. occidentalis, which is also comprised of a collagen layer, a thick layer of intertwined cells, and spicules. Follicle cells showed vesicles containing single phagocytosed spermatozoa within their cytoplasm. Additionally, lipids and other inclusions were observed within the cytoplasm of follicle cells. It is likely that follicle cells recapture nutrients by phagocytosing spermatozoa and use them to form lipids and other inclusions. Such sperm phagocytosis is usually performed in higher invertebrates and vertebrates by Sertoli cells that are located in the testis wall. While Sertoli cells develop a wide range of functions such as creating a blood-testis barrier, providing crucial factors to ensure correct progression of spermatogenesis, and phagocytosis of aberrant, degenerating, and unreleased sperm cells, sponge follicle cells may only display phagocytotic activity on spermatogenic cells. Copyright 2010 Elsevier Ltd. All rights reserved.

  11. The modern calcifying sponge Spheciospongia vesparium (Lamarck, 1815), Great Bahama Bank: Implications for ancient sponge mud-mounds

    NASA Astrophysics Data System (ADS)

    Neuweiler, Fritz; Burdige, David J.

    2005-04-01

    Modern calcified siliceous sponges from the Great Bahama Bank, living at water depth ranges of 2 to 5 m, have been proposed as likely analogues for calcified sponges in Upper Jurassic sponge "reefs" (e.g., southern Germany), or Lower Jurassic bioherms that consist of reddish, spiculiferous limestones (e.g., Broccatello Formation of the Southern Alps). Indeed, sponge-related calcification or siliceous sponge diagenesis, in general, is widely considered a key feature for the mechanisms of accretion and textural maturation in Phanerozoic sponge mounds or spiculiferous carbonate mud-mounds. Based on a revisit of the original sites on the Great Bahama Bank (NW of Andros Island) the biostratonomy of the calcifying sponge Spheciospongia vesparium (Lamarck, 1815) was explored using the patterns of fluorescent dissolved organic matter (FDOM) as revealed by the application of three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy. Geochemical sampling distinguished between FDOM that was extracted from sponge tissue and FDOM that was intimately associated with CaCO 3 (from particles due to sediment agglutination and authigenic CaCO 3), both obtained from the living sponge at the sediment surface and from the calcified sponge at the shallow subsurface (from 5 to 10 cm of depth). As expected, the sponge tissue shows highest intensities for protein-like fluorescence. However, from the surface to the subsurface, there is a loss of such relatively pristine fluorescent material in the range of 70%. Humic-like fluorescence that occurs associated with sponge tissue is relatively mature or aged, thus it most probably represents seawater FDOM taken up through active filter feeding. Relative to the sponge tissue material, the FDOM patterns associated with Ca-carbonates show much lower total fluorescence intensities, by up to two orders of magnitude. The agglutinated sedimentary carbonate particles from the surface (pellets, ooids, grapestones) exclusively show a

  12. The role of burrowing sponges in bioerosion.

    PubMed

    Rützler, Klaus

    1975-09-01

    Among the large number of limestone-eroding organisms, sponges, mainly of the family Clinonidae are of special interest because of their efficient means of substratum penetration by cellular etching and because they release characteristically shaped calcium carbonate chips which can be detected in the mud-size fraction of many sediments. Identifiable trace fossils and sediments are of great ecological and paleoecological significance.As new data on the excavating mechanism have become available, the questions of burrowing rates and sediment production have gained importance. Extrapolation from shortterm experiments (under 6 months) on substrate invasion are inconclusive because of high initial penetration rates resulting from mechanical stimulation and lack of competition. New experiments show that the rate curve flattens after 6 months and that optimum longterm erosion of CaCO 3 does not exceed 700 mg m -2 year -1 (Cliona lampa and C. aprica). Substrate limitations and competition will further reduce this rate.By monitoring the production of CaCO 3 chips by Cliona lampa, it was possible to link activity patterns to certain environmental factors. Mechanical stimuli, high light intensity, strong currents and, possibly, low temperature seem to accelerate the burrowing process. Sponge-generated chips can make up over 40% of coral mud when deposited in the current shadow of the reef framework.Using transect counts and sponge area-biomass conversion factors, the mean abundance of burrowing sponges on the Bermuda platform could be calculated. On suitable hard bottom substrates it averages 16 g dry weight per m 2 . From this value the burrowing potential of sponges can be estimated as 256 g CaCO 3 per m 2 substrate per year. Since 97-98% of the eroded limestone remains in particulate form, the contribution of fine sediments can amount to 250 g m -2 year -1 .Attention is called to the fact that erosion rates by burrowers can not directly be compared with those of borers or

  13. High-Surface-Area CO2 Sponge: High Performance CO2 Scrubbing Based on Hollow Fiber-Supported Designer Ionic Liquid Sponges

    SciTech Connect

    None

    IMPACCT Project: The team from ORNL and Georgia Tech is developing a new technology that will act like a sponge, integrating a new, alcohol-based ionic liquid into hollow fibers (magnified image, right) to capture CO2 from the exhaust produced by coal-fired power plants. Ionic liquids, or salts that exist in liquid form, are promising materials for carbon capture and storage, but their tendency to thicken when combined with CO2 limits their efficiency and poses a challenge for their development as a cost-effective alternative to current-generation solutions. Adding alcohol to the mix limits this tendency to thicken in the presence ofmore » CO2 but can also make the liquid more likely to evaporate, which would add significantly to the cost of CO2 capture. To solve this problem, ORNL is developing new classes of ionic liquids with high capacity for absorbing CO2. ORNL’s sponge would reduce the cost associated with the energy that would need to be diverted from power plants to capture CO2 and release it for storage.« less

  14. Two distinct microbial communities revealed in the sponge Cinachyrella

    PubMed Central

    Cuvelier, Marie L.; Blake, Emily; Mulheron, Rebecca; McCarthy, Peter J.; Blackwelder, Patricia; Thurber, Rebecca L. Vega; Lopez, Jose V.

    2014-01-01

    Marine sponges are vital components of benthic and coral reef ecosystems, providing shelter and nutrition for many organisms. In addition, sponges act as an essential carbon and nutrient link between the pelagic and benthic environment by filtering large quantities of seawater. Many sponge species harbor a diverse microbial community (including Archaea, Bacteria and Eukaryotes), which can constitute up to 50% of the sponge biomass. Sponges of the genus Cinachyrella are common in Caribbean and Floridian reefs and their archaeal and bacterial microbiomes were explored here using 16S rRNA gene tag pyrosequencing. Cinachyrella specimens and seawater samples were collected from the same South Florida reef at two different times of year. In total, 639 OTUs (12 archaeal and 627 bacterial) belonging to 2 archaeal and 21 bacterial phyla were detected in the sponges. Based on their microbiomes, the six sponge samples formed two distinct groups, namely sponge group 1 (SG1) with lower diversity (Shannon-Weiner index: 3.73 ± 0.22) and SG2 with higher diversity (Shannon-Weiner index: 5.95 ± 0.25). Hosts' 28S rRNA gene sequences further confirmed that the sponge specimens were composed of two taxa closely related to Cinachyrella kuekenthalli. Both sponge groups were dominated by Proteobacteria, but Alphaproteobacteria were significantly more abundant in SG1. SG2 harbored many bacterial phyla (>1% of sequences) present in low abundance or below detection limits (<0.07%) in SG1 including: Acidobacteria, Chloroflexi, Gemmatimonadetes, Nitrospirae, PAUC34f, Poribacteria, and Verrucomicrobia. Furthermore, SG1 and SG2 only had 95 OTUs in common, representing 30.5 and 22.4% of SG1 and SG2's total OTUs, respectively. These results suggest that the sponge host may exert a pivotal influence on the nature and structure of the microbial community and may only be marginally affected by external environment parameters. PMID:25408689

  15. Phylogenetically and Spatially Close Marine Sponges Harbour Divergent Bacterial Communities

    PubMed Central

    Hardoim, Cristiane C. P.; Esteves, Ana I. S.; Pires, Francisco R.; Gonçalves, Jorge M. S.; Cox, Cymon J.; Xavier, Joana R.; Costa, Rodrigo

    2012-01-01

    Recent studies have unravelled the diversity of sponge-associated bacteria that may play essential roles in sponge health and metabolism. Nevertheless, our understanding of this microbiota remains limited to a few host species found in restricted geographical localities, and the extent to which the sponge host determines the composition of its own microbiome remains a matter of debate. We address bacterial abundance and diversity of two temperate marine sponges belonging to the Irciniidae family - Sarcotragus spinosulus and Ircinia variabilis – in the Northeast Atlantic. Epifluorescence microscopy revealed that S. spinosulus hosted significantly more prokaryotic cells than I. variabilis and that prokaryotic abundance in both species was about 4 orders of magnitude higher than in seawater. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) profiles of S. spinosulus and I. variabilis differed markedly from each other – with higher number of ribotypes observed in S. spinosulus – and from those of seawater. Four PCR-DGGE bands, two specific to S. spinosulus, one specific to I. variabilis, and one present in both sponge species, affiliated with an uncultured sponge-specific phylogenetic cluster in the order Acidimicrobiales (Actinobacteria). Two PCR-DGGE bands present exclusively in S. spinosulus fingerprints affiliated with one sponge-specific phylogenetic cluster in the phylum Chloroflexi and with sponge-derived sequences in the order Chromatiales (Gammaproteobacteria), respectively. One Alphaproteobacteria band specific to S. spinosulus was placed in an uncultured sponge-specific phylogenetic cluster with a close relationship to the genus Rhodovulum. Our results confirm the hypothesized host-specific composition of bacterial communities between phylogenetically and spatially close sponge species in the Irciniidae family, with S. spinosulus displaying higher bacterial community diversity and distinctiveness than I. variabilis. These

  16. Pyrosequencing reveals highly diverse and species-specific microbial communities in sponges from the Red Sea

    PubMed Central

    Lee, On On; Wang, Yong; Yang, Jiangke; Lafi, Feras F; Al-Suwailem, Abdulaziz; Qian, Pei-Yuan

    2011-01-01

    Marine sponges are associated with a remarkable array of microorganisms. Using a tag pyrosequencing technology, this study was the first to investigate in depth the microbial communities associated with three Red Sea sponges, Hyrtios erectus, Stylissa carteri and Xestospongia testudinaria. We revealed highly diverse sponge-associated bacterial communities with up to 1000 microbial operational taxonomic units (OTUs) and richness estimates of up to 2000 species. Altogether, 26 bacterial phyla were detected from the Red Sea sponges, 11 of which were absent from the surrounding sea water and 4 were recorded in sponges for the first time. Up to 100 OTUs with richness estimates of up to 300 archaeal species were revealed from a single sponge species. This is by far the highest archaeal diversity ever recorded for sponges. A non-negligible proportion of unclassified reads was observed in sponges. Our results demonstrated that the sponge-associated microbial communities remained highly consistent in the same sponge species from different locations, although they varied at different degrees among different sponge species. A significant proportion of the tag sequences from the sponges could be assigned to one of the sponge-specific clusters previously defined. In addition, the sponge-associated microbial communities were consistently divergent from those present in the surrounding sea water. Our results suggest that the Red Sea sponges possess highly sponge-specific or even sponge-species-specific microbial communities that are resistant to environmental disturbance, and much of their microbial diversity remains to be explored. PMID:21085196

  17. Shock absorber servicing tool

    NASA Technical Reports Server (NTRS)

    Koepler, Jack L. (Inventor); Hill, Robert L. (Inventor)

    1981-01-01

    A tool to assist in the servicing of a shock absorber wherein the shock absorber is constructed of a pair of aligned gas and liquid filled chambers. Each of the chambers is separated by a movable separator member. Maximum efficiency of the shock absorber is achieved in the locating of a precise volume of gas within the gas chamber and a precise volume of liquid within the liquid chamber. The servicing tool of this invention employs a rod which is to connect with the separator and by observation of the position of the rod with respect to the gauge body, the location of the separator is ascertained even though it is not directly observable.

  18. Mechanical energy absorber

    NASA Technical Reports Server (NTRS)

    Wesselski, Clarence J. (Inventor)

    1993-01-01

    An energy absorbing system for controlling the force where a moving object engages a stationary stop and where the system utilized telescopic tubular members, energy absorbing diaphragm elements, force regulating disc springs, and a return spring to return the telescoping member to its start position after stroking is presented. The energy absorbing system has frusto-conical diaphragm elements frictionally engaging the shaft and are opposed by a force regulating set of disc springs. In principle, this force feedback mechanism serves to keep the stroking load at a reasonable level even if the friction coefficient increases greatly. This force feedback device also serves to desensitize the singular and combined effects of manufacturing tolerances, sliding surface wear, temperature changes, dynamic effects, and lubricity.

  19. The Sponge Pump: The Role of Current Induced Flow in the Design of the Sponge Body Plan

    PubMed Central

    Leys, Sally P.; Yahel, Gitai; Reidenbach, Matthew A.; Tunnicliffe, Verena; Shavit, Uri; Reiswig, Henry M.

    2011-01-01

    Sponges are suspension feeders that use flagellated collar-cells (choanocytes) to actively filter a volume of water equivalent to many times their body volume each hour. Flow through sponges is thought to be enhanced by ambient current, which induces a pressure gradient across the sponge wall, but the underlying mechanism is still unknown. Studies of sponge filtration have estimated the energetic cost of pumping to be <1% of its total metabolism implying there is little adaptive value to reducing the cost of pumping by using “passive” flow induced by the ambient current. We quantified the pumping activity and respiration of the glass sponge Aphrocallistes vastus at a 150 m deep reef in situ and in a flow flume; we also modeled the glass sponge filtration system from measurements of the aquiferous system. Excurrent flow from the sponge osculum measured in situ and in the flume were positively correlated (r>0.75) with the ambient current velocity. During short bursts of high ambient current the sponges filtered two-thirds of the total volume of water they processed daily. Our model indicates that the head loss across the sponge collar filter is 10 times higher than previously estimated. The difference is due to the resistance created by a fine protein mesh that lines the collar, which demosponges also have, but was so far overlooked. Applying our model to the in situ measurements indicates that even modest pumping rates require an energetic expenditure of at least 28% of the total in situ respiration. We suggest that due to the high cost of pumping, current-induced flow is highly beneficial but may occur only in thin walled sponges living in high flow environments. Our results call for a new look at the mechanisms underlying current-induced flow and for reevaluation of the cost of biological pumping and its evolutionary role, especially in sponges. PMID:22180779

  20. Shock Absorbing System

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A lightweight, inexpensive shock-absorbing system, developed by Langley Research Center 20 years ago, is now in service as safety device for an automated railway at Duke University Medical Center. The transportation system travels at about 25 miles per hour, carrying patients, visitors, staff and cargo. At the end of each guideway of the system are "frangible," (breakable) tube "buffers." If a slowing car fails to make a complete stop at the terminal, it would bump and shatter the tubes, absorbing energy that might otherwise jolt the passengers or damage the vehicle.

  1. The Life of a Sponge in a Sandy Lagoon.

    PubMed

    Ilan, M; Abelson, A

    1995-12-01

    Infaunal soft-bottom invertebrates benefit from the presence of sediment, but sedimentation is potentially harmful for hard-bottom dwellers. Most sponges live on hard bottom, but on coral reefs in the Red Sea, the species Biemna ehrenbergi (Keller, 1889) is found exclusively in soft-bottom lagoons, usually in the shallowest part. This location is a sink environment, which increases the deposition of particulate organic matter. Most of the sponge body is covered by sediment, but the chimney-like siphons protrude from the sediment surface. The sponge is attached to the buried beach-rock, which reduces the risk of dislodgment during storms. Dye injected above and into the sediment revealed, for the first time, a sponge pumping interstitial water (rich with particles and nutrients) into its aquiferous system. Visual examination of plastic replicas of the aquiferous system and electron microscopical analysis of sponge tissue revealed that the transcellular ostia are mostly located on the buried surface of the sponge. The oscula, however, are located on top of the siphons; their elevated position and their ability to close combine to prevent the filtering system outflow from clogging. The transcellular ostia presumably remain open due to cellular mobility. The sponge maintains a large population of bacteriocytes, which contains bacteria of several different species. Some of these bacteria disintegrate, and may be consumed by the sponge.

  2. Prevalence and Mechanisms of Dynamic Chemical Defenses in Tropical Sponges

    PubMed Central

    Rohde, Sven; Nietzer, Samuel; Schupp, Peter J.

    2015-01-01

    Sponges and other sessile invertebrates are lacking behavioural escape or defense mechanisms and rely therefore on morphological or chemical defenses. Studies from terrestrial systems and marine algae demonstrated facultative defenses like induction and activation to be common, suggesting that sessile marine organisms also evolved mechanisms to increase the efficiency of their chemical defense. However, inducible defenses in sponges have not been investigated so far and studies on activated defenses are rare. We investigated whether tropical sponge species induce defenses in response to artificial predation and whether wounding triggers defense activation. Additionally, we tested if these mechanisms are also used to boost antimicrobial activity to avoid bacterial infection. Laboratory experiments with eight pacific sponge species showed that 87% of the tested species were chemically defended. Two species, Stylissa massa and Melophlus sarasinorum, induced defenses in response to simulated predation, which is the first demonstration of induced antipredatory defenses in marine sponges. One species, M. sarasinorum, also showed activated defense in response to wounding. Interestingly, 50% of the tested sponge species demonstrated induced antimicrobial defense. Simulated predation increased the antimicrobial defenses in Aplysinella sp., Cacospongia sp., M. sarasinorum, and S. massa. Our results suggest that wounding selects for induced antimicrobial defenses to protect sponges from pathogens that could otherwise invade the sponge tissue via feeding scars. PMID:26154741

  3. Keratin sponge/hydrogel part 1. fabrication and characterization

    USDA-ARS?s Scientific Manuscript database

    Keratin sponge/hydrogel products formed by either the oxidation or reduction of U.S. domestic fine- or coarse-grade wool exhibited distinctively different topologies and molecular weights of 6- 8 kDa and 40-60 kDa, each with unique macro-porous structure and microstructural behaviors. The sponge/ ...

  4. The Dimension of the Pore Space in Sponges

    ERIC Educational Resources Information Center

    Silva, L. H. F.; Yamashita, M. T.

    2009-01-01

    A simple experiment to reveal the dimension of the pore space in sponges is proposed. This experiment is suitable for the first year of a physics or engineering course. The calculated dimension of the void space in a sponge of density 16 mg cm[superscript -3] was 2.948 [plus or minus] 0.008. (Contains 2 figures.)

  5. Highly deformation-tolerant carbon nanotube sponges as supercapacitor electrodes.

    PubMed

    Li, Peixu; Kong, Chuiyan; Shang, Yuanyuan; Shi, Enzheng; Yu, Yuntao; Qian, Weizhong; Wei, Fei; Wei, Jinquan; Wang, Kunlin; Zhu, Hongwei; Cao, Anyuan; Wu, Dehai

    2013-09-21

    Developing flexible and deformable supercapacitor electrodes based on porous materials is of high interest in energy related fields. Here, we show that carbon nanotube sponges, consisting of highly porous conductive networks, can serve as compressible and deformation-tolerant supercapacitor electrodes in aqueous or organic electrolytes. In aqueous electrolytes, the sponges maintain a similar specific capacitance (>90% of the original value) under a predefined compressive strain of 50% (corresponding to a volume reduction of 50%), and retain more than 70% of the original capacitance under 80% strain while the volume normalized capacitance increases by 3-fold. The sponge electrode maintains a stable performance after 1000 large strain compression cycles. A coin-shaped cell assembled with these sponges shows excellent stability over 15,000 charging cycles with negligible degradation after 500 cycles. Our results indicate that carbon nanotube sponges have the potential to fabricate deformable supercapacitor electrodes with stable performance.

  6. Type I Collagen and Collagen Mimetics as Angiogenesis Promoting Superpolymers

    SciTech Connect

    Twardowski, T.; Fertala, A.; Orgel, J.P.R.O.

    Angiogenesis, the development of blood vessels from the pre-existing vasculature, is a key component of embryogenesis and tissue regeneration. Angiogenesis also drives pathologies such as tumor growth and metastasis, and hemangioma development in newborns. On the other hand, promotion of angiogenesis is needed in tissues with vascular insufficiencies, and in bioengineering, to endow tissue substitutes with appropriate microvasculatures. Therefore, much research has focused on defining mechanisms of angiogenesis, and identifying pro- and anti-angiogenic molecules. Type I collagen, the most abundant protein in humans, potently stimulates angiogenesis in vitro and in vivo. Crucial to its angiogenic activity appears to be ligationmore » and possibly clustering of endothelial cell (EC) surface {alpha}1{beta}1/{alpha}2{beta}1 integrin receptors by the GFPGER502-507 sequence of the collagen fibril. However, additional aspects of collagen structure and function that may modulate its angiogenic properties are discussed. Moreover, type I collagen and fibrin, another angiogenic polymer, share several structural features. These observations suggest strategies for creating 'angiogenic superpolymers', including: modifying type I collagen to influence its biological half-life, immunogenicity, and integrin binding capacity; genetically engineering fibrillar collagens to include additional integrin binding sites or angiogenic determinants, and remove unnecessary or deleterious sequences without compromising fibril integrity; and exploring the suitability of poly(ortho ester), PEG-lysine copolymer, tubulin, and cholesteric cuticle as collagen mimetics, and suggesting means of modifying them to display ideal angiogenic properties. The collagenous and collagen mimetic angiogenic superpolymers described here may someday prove useful for many applications in tissue engineering and human medicine.« less

  7. Compression-induced structural and mechanical changes of fibrin-collagen composites.

    PubMed

    Kim, O V; Litvinov, R I; Chen, J; Chen, D Z; Weisel, J W; Alber, M S

    2017-07-01

    Fibrin and collagen as well as their combinations play an important biological role in tissue regeneration and are widely employed in surgery as fleeces or sealants and in bioengineering as tissue scaffolds. Earlier studies demonstrated that fibrin-collagen composite networks displayed improved tensile mechanical properties compared to the isolated protein matrices. Unlike previous studies, here unconfined compression was applied to a fibrin-collagen filamentous polymer composite matrix to study its structural and mechanical responses to compressive deformation. Combining collagen with fibrin resulted in formation of a composite hydrogel exhibiting synergistic mechanical properties compared to the isolated fibrin and collagen matrices. Specifically, the composite matrix revealed a one order of magnitude increase in the shear storage modulus at compressive strains>0.8 in response to compression compared to the mechanical features of individual components. These material enhancements were attributed to the observed structural alterations, such as network density changes, an increase in connectivity along with criss-crossing, and bundling of fibers. In addition, the compressed composite collagen/fibrin networks revealed a non-linear transformation of their viscoelastic properties with softening and stiffening regimes. These transitions were shown to depend on protein concentrations. Namely, a decrease in protein content drastically affected the mechanical response of the networks to compression by shifting the onset of stiffening to higher degrees of compression. Since both natural and artificially composed extracellular matrices experience compression in various (patho)physiological conditions, our results provide new insights into the structural biomechanics of the polymeric composite matrix that can help to create fibrin-collagen sealants, sponges, and tissue scaffolds with tunable and predictable mechanical properties. Copyright © 2016 Elsevier B.V. All rights

  8. Shock Absorbing Helmets

    NASA Technical Reports Server (NTRS)

    1978-01-01

    This paper presents a description of helmets used by football players that offer three times the shock-absorbing capacity of earlier types. An interior padding for the helmets, composed of Temper Foam, first used by NASA's Ames Research Center in the design of aircraft seats is described.

  9. Neutron Absorbing Alloys

    DOEpatents

    Mizia, Ronald E.; Shaber, Eric L.; DuPont, John N.; Robino, Charles V.; Williams, David B.

    2004-05-04

    The present invention is drawn to new classes of advanced neutron absorbing structural materials for use in spent nuclear fuel applications requiring structural strength, weldability, and long term corrosion resistance. Particularly, an austenitic stainless steel alloy containing gadolinium and less than 5% of a ferrite content is disclosed. Additionally, a nickel-based alloy containing gadolinium and greater than 50% nickel is also disclosed.

  10. Barcoding Sponges: An Overview Based on Comprehensive Sampling

    PubMed Central

    Vargas, Sergio; Schuster, Astrid; Sacher, Katharina; Büttner, Gabrielle; Schätzle, Simone; Läuchli, Benjamin; Hall, Kathryn; Hooper, John N. A.; Erpenbeck, Dirk; Wörheide, Gert

    2012-01-01

    Background Phylum Porifera includes ∼8,500 valid species distributed world-wide in aquatic ecosystems ranging from ephemeral fresh-water bodies to coastal environments and the deep-sea. The taxonomy and systematics of sponges is complicated, and morphological identification can be both time consuming and erroneous due to phenotypic convergence and secondary losses, etc. DNA barcoding can provide sponge biologists with a simple and rapid method for the identification of samples of unknown taxonomic membership. The Sponge Barcoding Project (www.spongebarcoding.org), the first initiative to barcode a non-bilaterian metazoan phylum, aims to provide a comprehensive DNA barcode database for Phylum Porifera. Methodology/Principal Findings ∼7,400 sponge specimens have been extracted, and amplification of the standard COI barcoding fragment has been attempted for approximately 3,300 museum samples with ∼25% mean amplification success. Based on this comprehensive sampling, we present the first report on the workflow and progress of the sponge barcoding project, and discuss some common pitfalls inherent to the barcoding of sponges. Conclusion A DNA-barcoding workflow capable of processing potentially large sponge collections has been developed and is routinely used for the Sponge Barcoding Project with success. Sponge specific problems such as the frequent co-amplification of non-target organisms have been detected and potential solutions are currently under development. The initial success of this innovative project have already demonstrated considerable refinement of sponge systematics, evaluating morphometric character importance, geographic phenotypic variability, and the utility of the standard barcoding fragment for Porifera (despite its conserved evolution within this basal metazoan phylum). PMID:22802937

  11. Lifestyle Evolution in Cyanobacterial Symbionts of Sponges

    PubMed Central

    Burgsdorf, Ilia; Slaby, Beate M.; Handley, Kim M.; Haber, Markus; Blom, Jochen; Marshall, Christopher W.; Gilbert, Jack A.; Hentschel, Ute

    2015-01-01

    ABSTRACT The “Candidatus Synechococcus spongiarum” group includes different clades of cyanobacteria with high 16S rRNA sequence identity (~99%) and is the most abundant and widespread cyanobacterial symbiont of marine sponges. The first draft genome of a “Ca. Synechococcus spongiarum” group member was recently published, providing evidence of genome reduction by loss of genes involved in several nonessential functions. However, “Ca. Synechococcus spongiarum” includes a variety of clades that may differ widely in genomic repertoire and consequently in physiology and symbiotic function. Here, we present three additional draft genomes of “Ca. Synechococcus spongiarum,” each from a different clade. By comparing all four symbiont genomes to those of free-living cyanobacteria, we revealed general adaptations to life inside sponges and specific adaptations of each phylotype. Symbiont genomes shared about half of their total number of coding genes. Common traits of “Ca. Synechococcus spongiarum” members were a high abundance of DNA modification and recombination genes and a reduction in genes involved in inorganic ion transport and metabolism, cell wall biogenesis, and signal transduction mechanisms. Moreover, these symbionts were characterized by a reduced number of antioxidant enzymes and low-weight peptides of photosystem II compared to their free-living relatives. Variability within the “Ca. Synechococcus spongiarum” group was mostly related to immune system features, potential for siderophore-mediated iron transport, and dependency on methionine from external sources. The common absence of genes involved in synthesis of residues, typical of the O antigen of free-living Synechococcus species, suggests a novel mechanism utilized by these symbionts to avoid sponge predation and phage attack. PMID:26037118

  12. Lifestyle Evolution in Cyanobacterial Symbionts of Sponges

    SciTech Connect

    Burgsdorf, Ilia; Slaby, Beate M.; Handley, Kim M.

    The “Candidatus Synechococcus spongiarum” group includes different clades of cyanobacteria with high 16S rRNA sequence identity (~99%) and is the most abundant and widespread cyanobacterial symbiont of marine sponges. The first draft genome of a “Ca. Synechococcus spongiarum” group member was recently published, providing evidence of genome reduction by loss of genes involved in several nonessential functions. However, “Ca. Synechococcus spongiarum” includes a variety of clades that may differ widely in genomic repertoire and consequently in physiology and symbiotic function. Here, we present three additional draft genomes of “Ca. Synechococcus spongiarum,” each from a different clade. By comparing all fourmore » symbiont genomes to those of free-living cyanobacteria, we revealed general adaptations to life inside sponges and specific adaptations of each phylotype. Symbiont genomes shared about half of their total number of coding genes. Common traits of “Ca. Synechococcus spongiarum” members were a high abundance of DNA modification and recombination genes and a reduction in genes involved in inorganic ion transport and metabolism, cell wall biogenesis, and signal transduction mechanisms. Moreover, these symbionts were characterized by a reduced number of antioxidant enzymes and low-weight peptides of photosystem II compared to their free-living relatives. Variability within the “Ca. Synechococcus spongiarum” group was mostly related to immune system features, potential for siderophore-mediated iron transport, and dependency on methionine from external sources. The common absence of genes involved in synthesis of residues, typical of the O antigen of free-living Synechococcus species, suggests a novel mechanism utilized by these symbionts to avoid sponge predation and phage attack.« less

  13. Lifestyle Evolution in Cyanobacterial Symbionts of Sponges

    DOE PAGES

    Burgsdorf, Ilia; Slaby, Beate M.; Handley, Kim M.; ...

    2015-06-02

    The “Candidatus Synechococcus spongiarum” group includes different clades of cyanobacteria with high 16S rRNA sequence identity (~99%) and is the most abundant and widespread cyanobacterial symbiont of marine sponges. The first draft genome of a “Ca. Synechococcus spongiarum” group member was recently published, providing evidence of genome reduction by loss of genes involved in several nonessential functions. However, “Ca. Synechococcus spongiarum” includes a variety of clades that may differ widely in genomic repertoire and consequently in physiology and symbiotic function. Here, we present three additional draft genomes of “Ca. Synechococcus spongiarum,” each from a different clade. By comparing all fourmore » symbiont genomes to those of free-living cyanobacteria, we revealed general adaptations to life inside sponges and specific adaptations of each phylotype. Symbiont genomes shared about half of their total number of coding genes. Common traits of “Ca. Synechococcus spongiarum” members were a high abundance of DNA modification and recombination genes and a reduction in genes involved in inorganic ion transport and metabolism, cell wall biogenesis, and signal transduction mechanisms. Moreover, these symbionts were characterized by a reduced number of antioxidant enzymes and low-weight peptides of photosystem II compared to their free-living relatives. Variability within the “Ca. Synechococcus spongiarum” group was mostly related to immune system features, potential for siderophore-mediated iron transport, and dependency on methionine from external sources. The common absence of genes involved in synthesis of residues, typical of the O antigen of free-living Synechococcus species, suggests a novel mechanism utilized by these symbionts to avoid sponge predation and phage attack.« less

  14. 21 CFR 529.1003 - Flurogestone acetate-impregnated vaginal sponge.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Flurogestone acetate-impregnated vaginal sponge... § 529.1003 Flurogestone acetate-impregnated vaginal sponge. (a) Specifications. Each vaginal sponge... ewes during their normal breeding season. (2) Limitations. Using applicator provided, insert sponge...

  15. 21 CFR 878.4014 - Nonresorbable gauze/sponge for external use.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nonresorbable gauze/sponge for external use. 878... Nonresorbable gauze/sponge for external use. (a) Identification. A nonresorbable gauze/sponge for external use... include a nonresorbable gauze/sponge for external use that contains added drugs such as antimicrobial...

  16. Thermal and infrared-diode laser effects on indocyanine-green-treated corneal collagen

    NASA Astrophysics Data System (ADS)

    Timberlake, George T.; Patmore, Ann; Shallal, Assaad; McHugh, Dominic; Marshall, John

    1993-07-01

    It has been suggested that laser welds of collagenous tissues form by interdigitation and chemical bonding of thermally 'unraveled' collagen fibrils. We investigated this proposal by attempting to weld highly collagenous, avascular corneal tissue with an infrared (IR) diode laser as follows. First, the temperature at which corneal collagen shrinks and collagen fibrils 'split' into subfibrillary components was determined. Second, since use of a near-IR laser wavelength necessitated addition of an absorbing dye (indocyanine green (ICG) to the cornea, we measured absorption spectra of ICG-treated tissue to ensure that peak ICG absorbance did not change markedly when ICG was present in the cornea. Third, using gel electrophoresis of thermally altered corneal collagen, we searched for covalently crosslinked compounds predicted by the proposed welding mechanism. Finally, we attempted to weld partial thickness corneal incisions infused with ICG. Principal experimental findings were as follows: (1) Human corneal (type I) collagen splits into subfibrillary components at approximately 63 degree(s)C, the same temperature that produces collagen shrinkage. (2) Peak ICG absorption does not change significantly in corneal stroma or with laser heating. (3) No evidence was found for the formation of novel compounds or the loss of proteins as a result of tissue heating. All tissue treated with ICG, however, exhibited a novel 244 kD protein band indicating chemical activity between collagen and corneal stromal components. (4) Laser welding corneal incisions was unsuccessful possibly due to shrinkage of the sides of the incision, lack of incision compression during heating, or a less than optimal combination of ICG concentration and radiant exposure. In summary, these experiments demonstrate the biochemical and morphological complexity of ICG-enhanced IR laser-tissue welding and the need for further investigation of laser welding mechanisms.

  17. Socket augmentation using a commercial collagen-based product--an animal study in pigs.

    PubMed

    Kunert-Keil, Christiane; Gredes, Tomasz; Heinemann, Friedhelm; Dominiak, Marzena; Botzenhart, Ute; Gedrange, Tomasz

    2015-01-01

    The aim of the present study was to identify properties of pure collagen for augmentation techniques and compare to a proved xenogenic material and natural bone regeneration. For that the osteogenesis of extraction alveoli after augmentation with a collagen cone covered with an absorbable collagen membrane in a single product (PARASORB Sombrero®, Resorba) was evaluated in a pig model. Extraction alveoli were treated with the collagen cone and the collagen membrane in a single product (test group; n=7) or demineralized bovine bone mineral and a collagen membrane (two separate products; positive control; n=7). Untreated alveoli were used (n=6) as negative controls.(1) Bone specimens were extracted 1 and 3 months after teeth extraction. Serial longitudinal sections were stained with Masson Goldner trichrome. Furthermore, bone specimens were examined using X-ray analyses. Significant differences of bone atrophy were detected 12 weeks after material insertion using X-ray analyses. The bone atrophy was reduced by approximately 32% after insertion of the positive control (P=0.046). Bone atrophy reached 37.6% of those from untreated alveoli (P=0.002) using the test group. After 4 weeks, bone formation was noticeable in most sites, whereas after 12 weeks of healing, specimens of all groups exhibited nearly complete osseous organization of the former defected area. The mandibulary bone texture showed typical spongious bone structures. Histomorphometric analyses revealed after 4 and 12 weeks significant higher levels of bone marrow in test and negative control than in positive control. Quantification of bone tissue and osteoid does not show any significant difference. The present study confirms reduced bone resorption following socket augmentation with an absorbable collagen membrane with collagen cone while the resulting bone structure is similar to natural bone regeneration. Pure collagen can be used for bone augmentation, and shows over other xenogenic materials, a clear

  18. Metasurface Broadband Solar Absorber

    PubMed Central

    Azad, Abul K.; Kort-Kamp, Wilton J. M.; Sykora, Milan; Weisse-Bernstein, Nina R.; Luk, Ting S.; Taylor, Antoinette J.; Dalvit, Diego A. R.; Chen, Hou-Tong

    2016-01-01

    We demonstrate a broadband, polarization independent, wide-angle absorber based on a metallic metasurface architecture, which accomplishes greater than 90% absorptance in the visible and near-infrared range of the solar spectrum, and exhibits low absorptivity (emissivity) at mid- and far-infrared wavelengths. The complex unit cell of the metasurface solar absorber consists of eight pairs of gold nano-resonators that are separated from a gold ground plane by a thin silicon dioxide spacer. Our experimental measurements reveal high-performance absorption over a wide range of incidence angles for both s- and p-polarizations. We also investigate numerically the frequency-dependent field and current distributions to elucidate how the absorption occurs within the metasurface structure. PMID:26828999

  19. Metasurface Broadband Solar Absorber.

    PubMed

    Azad, Abul K; Kort-Kamp, Wilton J M; Sykora, Milan; Weisse-Bernstein, Nina R; Luk, Ting S; Taylor, Antoinette J; Dalvit, Diego A R; Chen, Hou-Tong

    2016-02-01

    We demonstrate a broadband, polarization independent, wide-angle absorber based on a metallic metasurface architecture, which accomplishes greater than 90% absorptance in the visible and near-infrared range of the solar spectrum, and exhibits low absorptivity (emissivity) at mid- and far-infrared wavelengths. The complex unit cell of the metasurface solar absorber consists of eight pairs of gold nano-resonators that are separated from a gold ground plane by a thin silicon dioxide spacer. Our experimental measurements reveal high-performance absorption over a wide range of incidence angles for both s- and p-polarizations. We also investigate numerically the frequency-dependent field and current distributions to elucidate how the absorption occurs within the metasurface structure.

  20. Metasurface Broadband Solar Absorber

    DOE PAGES

    Azad, Abul K.; Kort-Kamp, Wilton J. M.; Sykora, Milan; ...

    2016-02-01

    Here, we demonstrate a broadband, polarization independent, wide-angle absorber based on a metallic metasurface architecture, which accomplishes greater than 90% absorptance in the visible and near-infrared range of the solar spectrum, and exhibits low absorptivity (emissivity) at mid- and far-infrared wavelengths. The complex unit cell of the metasurface solar absorber consists of eight pairs of gold nano-resonators that are separated from a gold ground plane by a thin silicon dioxide spacer. Moreover, our experimental measurements reveal high-performance absorption over a wide range of incidence angles for both s- and p-polarizations. We also investigate numerically the frequency-dependent field and current distributionsmore » to elucidate how the absorption occurs within the metasurface structure.« less

  1. Shape Memory Silk Protein Sponges for Minimally Invasive Tissue Regeneration.

    PubMed

    Brown, Joseph E; Moreau, Jodie E; Berman, Alison M; McSherry, Heather J; Coburn, Jeannine M; Schmidt, Daniel F; Kaplan, David L

    2017-01-01

    Porous silk protein scaffolds are designed to display shape memory characteristics and volumetric recovery following compression. Two strategies are utilized to realize shape recovery: addition of hygroscopic plasticizers like glycerol, and tyrosine modifications with hydrophilic sulfonic acid chemistries. Silk sponges are evaluated for recovery following 80% compressive strain, total porosity, pore size distribution, secondary structure development, in vivo volume retention, cell infiltration, and inflammatory responses. Glycerol-modified sponges recover up to 98.3% of their original dimensions following compression, while sulfonic acid/glycerol modified sponges swell in water up to 71 times their compressed volume, well in excess of their original size. Longer silk extraction times (lower silk molecular weights) and higher glycerol concentrations yielded greater flexibility and shape fidelity, with no loss in modulus following compression. Sponges are over 95% porous, with secondary structure analysis indicating glycerol-induced β-sheet physical crosslinking. Tyrosine modifications with sulfonic acid interfere with β-sheet formation. Glycerol-modified sponges exhibit improved rates of cellular infiltration at subcutaneous implant sites with minimal immune response in mice. They also degrade more rapidly than unmodified sponges, a result posited to be cell-mediated. Overall, this work suggests that silk sponges may be useful for minimally invasive deployment in soft tissue augmentation procedures. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Globally intertwined evolutionary history of giant barrel sponges

    NASA Astrophysics Data System (ADS)

    Swierts, Thomas; Peijnenburg, Katja T. C. A.; de Leeuw, Christiaan A.; Breeuwer, Johannes A. J.; Cleary, Daniel F. R.; de Voogd, Nicole J.

    2017-09-01

    Three species of giant barrel sponge are currently recognized in two distinct geographic regions, the tropical Atlantic and the Indo-Pacific. In this study, we used molecular techniques to study populations of giant barrel sponges across the globe and assessed whether the genetic structure of these populations agreed with current taxonomic consensus or, in contrast, whether there was evidence of cryptic species. Using molecular data, we assessed whether giant barrel sponges in each oceanic realm represented separate monophyletic lineages. Giant barrel sponges from 17 coral reef systems across the globe were sequenced for mitochondrial (partial CO1 and ATP6 genes) and nuclear (ATPsβ intron) DNA markers. In total, we obtained 395 combined sequences of the mitochondrial CO1 and ATP6 markers, which resulted in 17 different haplotypes. We compared a phylogenetic tree constructed from 285 alleles of the nuclear intron ATPsβ to the 17 mitochondrial haplotypes. Congruent patterns between mitochondrial and nuclear gene trees of giant barrel sponges provided evidence for the existence of multiple reproductively isolated species, particularly where they occurred in sympatry. The species complexes in the tropical Atlantic and the Indo-Pacific, however, do not form separate monophyletic lineages. This rules out the scenario that one species of giant barrel sponge developed into separate species complexes following geographic separation and instead suggests that multiple species of giant barrel sponges already existed prior to the physical separation of the Indo-Pacific and tropical Atlantic.

  3. Bioprospecting Sponge-Associated Microbes for Antimicrobial Compounds

    PubMed Central

    Indraningrat, Anak Agung Gede; Smidt, Hauke; Sipkema, Detmer

    2016-01-01

    Sponges are the most prolific marine organisms with respect to their arsenal of bioactive compounds including antimicrobials. However, the majority of these substances are probably not produced by the sponge itself, but rather by bacteria or fungi that are associated with their host. This review for the first time provides a comprehensive overview of antimicrobial compounds that are known to be produced by sponge-associated microbes. We discuss the current state-of-the-art by grouping the bioactive compounds produced by sponge-associated microorganisms in four categories: antiviral, antibacterial, antifungal and antiprotozoal compounds. Based on in vitro activity tests, identified targets of potent antimicrobial substances derived from sponge-associated microbes include: human immunodeficiency virus 1 (HIV-1) (2-undecyl-4-quinolone, sorbicillactone A and chartarutine B); influenza A (H1N1) virus (truncateol M); nosocomial Gram positive bacteria (thiopeptide YM-266183, YM-266184, mayamycin and kocurin); Escherichia coli (sydonic acid), Chlamydia trachomatis (naphthacene glycoside SF2446A2); Plasmodium spp. (manzamine A and quinolone 1); Leishmania donovani (manzamine A and valinomycin); Trypanosoma brucei (valinomycin and staurosporine); Candida albicans and dermatophytic fungi (saadamycin, 5,7-dimethoxy-4-p-methoxylphenylcoumarin and YM-202204). Thirty-five bacterial and 12 fungal genera associated with sponges that produce antimicrobials were identified, with Streptomyces, Pseudovibrio, Bacillus, Aspergillus and Penicillium as the prominent producers of antimicrobial compounds. Furthemore culture-independent approaches to more comprehensively exploit the genetic richness of antimicrobial compound-producing pathways from sponge-associated bacteria are addressed. PMID:27144573

  4. First report on chitinous holdfast in sponges (Porifera).

    PubMed

    Ehrlich, Hermann; Kaluzhnaya, Oksana V; Tsurkan, Mikhail V; Ereskovsky, Alexander; Tabachnick, Konstantin R; Ilan, Micha; Stelling, Allison; Galli, Roberta; Petrova, Olga V; Nekipelov, Serguei V; Sivkov, Victor N; Vyalikh, Denis; Born, René; Behm, Thomas; Ehrlich, Andre; Chernogor, Lubov I; Belikov, Sergei; Janussen, Dorte; Bazhenov, Vasilii V; Wörheide, Gert

    2013-07-07

    A holdfast is a root- or basal plate-like structure of principal importance that anchors aquatic sessile organisms, including sponges, to hard substrates. There is to date little information about the nature and origin of sponges' holdfasts in both marine and freshwater environments. This work, to our knowledge, demonstrates for the first time that chitin is an important structural component within holdfasts of the endemic freshwater demosponge Lubomirskia baicalensis. Using a variety of techniques (near-edge X-ray absorption fine structure, Raman, electrospray ionization mas spectrometry, Morgan-Elson assay and Calcofluor White staining), we show that chitin from the sponge holdfast is much closer to α-chitin than to β-chitin. Most of the three-dimensional fibrous skeleton of this sponge consists of spicule-containing proteinaceous spongin. Intriguingly, the chitinous holdfast is not spongin-based, and is ontogenetically the oldest part of the sponge body. Sequencing revealed the presence of four previously undescribed genes encoding chitin synthases in the L. baicalensis sponge. This discovery of chitin within freshwater sponge holdfasts highlights the novel and specific functions of this biopolymer within these ancient sessile invertebrates.

  5. Bioprospecting Sponge-Associated Microbes for Antimicrobial Compounds.

    PubMed

    Indraningrat, Anak Agung Gede; Smidt, Hauke; Sipkema, Detmer

    2016-05-02

    Sponges are the most prolific marine organisms with respect to their arsenal of bioactive compounds including antimicrobials. However, the majority of these substances are probably not produced by the sponge itself, but rather by bacteria or fungi that are associated with their host. This review for the first time provides a comprehensive overview of antimicrobial compounds that are known to be produced by sponge-associated microbes. We discuss the current state-of-the-art by grouping the bioactive compounds produced by sponge-associated microorganisms in four categories: antiviral, antibacterial, antifungal and antiprotozoal compounds. Based on in vitro activity tests, identified targets of potent antimicrobial substances derived from sponge-associated microbes include: human immunodeficiency virus 1 (HIV-1) (2-undecyl-4-quinolone, sorbicillactone A and chartarutine B); influenza A (H1N1) virus (truncateol M); nosocomial Gram positive bacteria (thiopeptide YM-266183, YM-266184, mayamycin and kocurin); Escherichia coli (sydonic acid), Chlamydia trachomatis (naphthacene glycoside SF2446A2); Plasmodium spp. (manzamine A and quinolone 1); Leishmania donovani (manzamine A and valinomycin); Trypanosoma brucei (valinomycin and staurosporine); Candida albicans and dermatophytic fungi (saadamycin, 5,7-dimethoxy-4-p-methoxylphenylcoumarin and YM-202204). Thirty-five bacterial and 12 fungal genera associated with sponges that produce antimicrobials were identified, with Streptomyces, Pseudovibrio, Bacillus, Aspergillus and Penicillium as the prominent producers of antimicrobial compounds. Furthemore culture-independent approaches to more comprehensively exploit the genetic richness of antimicrobial compound-producing pathways from sponge-associated bacteria are addressed.

  6. Exploring the diversity-stability paradigm using sponge microbial communities.

    PubMed

    Glasl, Bettina; Smith, Caitlin E; Bourne, David G; Webster, Nicole S

    2018-05-30

    A key concept in theoretical ecology is the positive correlation between biodiversity and ecosystem stability. When applying this diversity-stability concept to host-associated microbiomes, the following questions emerge: (1) Does microbial diversity influence the stability of microbiomes upon environmental fluctuations? (2) Do hosts that harbor high versus low microbial diversity differ in their stress response? To test the diversity-stability concept in host-associated microbiomes, we exposed six marine sponge species with varying levels of microbial diversity to non-lethal salinity disturbances and followed their microbial composition over time using 16S rRNA gene amplicon sequencing. No signs of sponge stress were evident following salinity amendment and microbiomes exhibited compositional resistance irrespective of their microbial diversity. Compositional stability of the sponge microbiome manifests itself at distinct host taxonomic and host microbial diversity groups, with (1) stable host genotype-specific microbiomes at oligotype-level; (2) stable host species-specific microbiomes at genus-level; and (3) stable and specific microbiomes at phylum-level for hosts with high versus low microbial diversity. The resistance of sponge microbiomes together with the overall stability of sponge holobionts upon salinity fluctuations suggest that the stability-diversity concept does not appear to hold for sponge microbiomes and provides further evidence for the widely recognized environmental tolerance of sponges.

  7. Preliminary Assessment of Sponge Biodiversity on Saba Bank, Netherlands Antilles

    PubMed Central

    Thacker, Robert W.; Díaz, M. Cristina; de Voogd, Nicole J.; van Soest, Rob W. M.; Freeman, Christopher J.; Mobley, Andrew S.; LaPietra, Jessica; Cope, Kevin; McKenna, Sheila

    2010-01-01

    Background Saba Bank Atoll, Netherlands Antilles, is one of the three largest atolls on Earth and provides habitat for an extensive coral reef community. To improve our knowledge of this vast marine resource, a survey of biodiversity at Saba Bank included a multi-disciplinary team that sampled fishes, mollusks, crustaceans, macroalgae, and sponges. Methodology/Principal Findings A single member of the dive team conducted surveys of sponge biodiversity during eight dives at six locations, at depths ranging from 15 to 30 m. This preliminary assessment documented the presence of 45 species pooled across multiple locations. Rarefaction analysis estimated that only 48 to 84% of species diversity was sampled by this limited effort, clearly indicating a need for additional surveys. An analysis of historical collections from Saba and Saba Bank revealed an additional 36 species, yielding a total of 81 sponge species recorded from this area. Conclusions/Significance This observed species composition is similar to that found on widespread Caribbean reefs, indicating that the sponge fauna of Saba Bank is broadly representative of the Caribbean as a whole. A robust population of the giant barrel sponge, Xestospongia muta, appeared healthy with none of the signs of disease or bleaching reported from other Caribbean reefs; however, more recent reports of anchor chain damage to these sponges suggests that human activities can have dramatic impacts on these communities. Opportunities to protect this extremely large habitat should be pursued, as Saba Bank may serve as a significant reservoir of sponge species diversity. PMID:20502643

  8. Apollo couch energy absorbers

    NASA Technical Reports Server (NTRS)

    Wesselski, C. J.; Drexel, R. E.

    1972-01-01

    Load attenuators for the Apollo spacecraft crew couch and its potential applications are described. Energy absorption is achieved through friction and cyclic deformation of material. In one concept, energy absorption is accomplished by rolling a compressed ring of metal between two surfaces. In another concept, energy is absorbed by forcing a plastically deformed washer along a rod. Among the design problems that had to be solved were material selection, fatigue life, ring slippage, lubrication, and friction loading.

  9. Ionized Absorbers in AGN

    NASA Technical Reports Server (NTRS)

    Mathur, S.

    1999-01-01

    As a part of this program, we observed three AGN:PKS2251 + 113, PG0043 = 039 and PLH909. Two objects show signatures of absorbtion in their UV spectra. Based on our earlier modeling of X-ray warm absorbents, we expected to observe X-ray observation in these objects. The third, PLH909, is known to have soft excess in EINSTEIN data. Attachment: "Exploratory ASCA observation of broad absorption line quasi-stellar objects".

  10. Nonlinear microscopy of collagen fibers

    NASA Astrophysics Data System (ADS)

    Strupler, M.; Pena, A.-M.; Hernest, M.; Tharaux, P.-L.; Fabre, A.; Marchal-Somme, J.; Crestani, B.; Débarre, D.; Martin, J.-L.; Beaurepaire, E.; Schanne-Klein, M.-C.

    2007-02-01

    We used intrinsic Second Harmonic Generation (SHG) by fibrillar collagen to visualize the three-dimensional architecture of collagen fibrosis at the micrometer scale using laser scanning nonlinear microscopy. We showed that SHG signals are highly specific to fibrillar collagen and provide a sensitive probe of the micrometer-scale structural organization of collagen in tissues. Moreover, recording simultaneously other nonlinear optical signals in a multimodal setup, we visualized the tissue morphology using Two-Photon Excited Fluorescence (2PEF) signals from endogenous chromophores such as NADH or elastin. We then compared different methods to determine accurate indexes of collagen fibrosis using nonlinear microscopy, given that most collagen fibrils are smaller than the microscope resolution and that second harmonic generation is a coherent process. In order to define a robust method to process our three-dimensional images, we either calculated the fraction of the images occupied by a significant SHG signal, or averaged SHG signal intensities. We showed that these scores provide an estimation of the extension of renal and pulmonary fibrosis in murine models, and that they clearly sort out the fibrotic mice.

  11. Characterisations of collagen-silver-hydroxyapatite nanocomposites

    NASA Astrophysics Data System (ADS)

    Ciobanu, C. S.; Popa, C. L.; Petre, C. C.; Jiga, G.; Trusca, R.; Predoi, D.

    2016-05-01

    The XRD analysis were performed to confirm the formation of hydroxyapatite structure in collagen-silver-hydroxyapatite nanocomposites. The molecular interaction in collagen-hydroxyapatite nanocomposites was highlighted by Fourier transform infrared spectroscopy (FTIR) analysis. The SEM showed a nanostructure of collagen-silverhydroxyapatite nanocomposites composed of nano needle-like particles in a veil with collagen texture. The presence of vibrational groups characteristics to the hydroxyapatite structure in collagen-silver-hydroxyapatite (AgHApColl) nanocomposites was investigated by FTIR.

  12. Imaging Prostate Cancer Microenvironment by Collagen Hybridization

    DTIC Science & Technology

    2016-10-01

    affinity to denatured collagens and collagens undergoing remodeling which simulate the microenvironment of metastatic tumors. We will focus on previously...specifically target digested collagens with unfolded and partially denatured collagen triple helices. 2. Demonstration of ex vivo and in vivo targeting...invasive prostate cancer due to the absence of non-specific affinity and high propensity to hybridize with denatured collagen strand (Aim 1). We

  13. Absorber for terahertz radiation management

    DOEpatents

    Biallas, George Herman; Apeldoorn, Cornelis; Williams, Gwyn P.; Benson, Stephen V.; Shinn, Michelle D.; Heckman, John D.

    2015-12-08

    A method and apparatus for minimizing the degradation of power in a free electron laser (FEL) generating terahertz (THz) radiation. The method includes inserting an absorber ring in the FEL beam path for absorbing any irregular THz radiation and thus minimizes the degradation of downstream optics and the resulting degradation of the FEL output power. The absorber ring includes an upstream side, a downstream side, and a plurality of wedges spaced radially around the absorber ring. The wedges form a scallop-like feature on the innermost edges of the absorber ring that acts as an apodizer, stopping diffractive focusing of the THz radiation that is not intercepted by the absorber. Spacing between the scallop-like features and the shape of the features approximates the Bartlett apodization function. The absorber ring provides a smooth intensity distribution, rather than one that is peaked on-center, thereby eliminating minor distortion downstream of the absorber.

  14. Long-term follow-up of the experimental replacement of the esophagus with a collagen-silicone composite tube.

    PubMed

    Takimoto, Y; Okumura, N; Nakamura, T; Natsume, T; Shimizu, Y

    1993-01-01

    This study investigated ways of preventing late stenosis after replacing the esophagus with a prosthetic device and increasing survival time in an animal model. In a previous study, the authors induced neoesophageal formation and re-epithelialization at an early stage, although stenosis in the chronic stage remained a problem, and long-term survival was prevented. The authors developed an artificial esophagus made from a collagen-silicone composite tube. The silicone tube (25 mm in diameter, 50 mm long, and 1 mm thick) was covered with collagen sponge (5 mm thick). The collagen sponge was intended to be replaced by host tissue, leading to neoesophageal regeneration. The authors thought stenosis was caused primarily by poor regeneration of submucosal tissue, rather than reepithelialization. Thus, they examined the grade of stenosis relative to the time the stent became dislodged. They concluded that the occurrence of stenosis after anastomosis depends upon the duration of stenting and that stenosis did not develop when the portion replaced by the artificial esophagus was stented for at least 4 weeks.

  15. Corrosion resistant neutron absorbing coatings

    DOEpatents

    Choi, Jor-Shan [El Cerrito, CA; Farmer, Joseph C [Tracy, CA; Lee, Chuck K [Hayward, CA; Walker, Jeffrey [Gaithersburg, MD; Russell, Paige [Las Vegas, NV; Kirkwood, Jon [Saint Leonard, MD; Yang, Nancy [Lafayette, CA; Champagne, Victor [Oxford, PA

    2012-05-29

    A method of forming a corrosion resistant neutron absorbing coating comprising the steps of spray or deposition or sputtering or welding processing to form a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material. Also a corrosion resistant neutron absorbing coating comprising a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material.

  16. Corrosion resistant neutron absorbing coatings

    DOEpatents

    Choi, Jor-Shan; Farmer, Joseph C; Lee, Chuck K; Walker, Jeffrey; Russell, Paige; Kirkwood, Jon; Yang, Nancy; Champagne, Victor

    2013-11-12

    A method of forming a corrosion resistant neutron absorbing coating comprising the steps of spray or deposition or sputtering or welding processing to form a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material. Also a corrosion resistant neutron absorbing coating comprising a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material.

  17. Reevaluation of the role of the polar groups of collagen in the platelet-collagen interaction.

    PubMed Central

    Chesney, C. M.; Pifer, D. D.; Crofford, L. J.; Huch, K. M.

    1983-01-01

    Chemical modification of collagen is a tool for exploring the platelet-collagen interaction. Since collagen must polymerize prior to the initiation of platelet aggregation and secretion, modification must be shown to affect platelet-collagen interaction and not collagen-collagen interaction. To address this point, the authors carried out the following chemical modifications on soluble monomeric collagen and preformed fibrillar collagen in parallel: 1) N-and O-acetylation, 2) esterification of the carboxyl groups, 3) succinylation of the free amino groups, 4) esterification of succinylated collagen. Intrinsic viscosity studies of the modified soluble collagens were consistent with normal triple helix conformation. Electron microscopy revealed all modified fibrillar collagen to maintain a fibrillar structure. Platelet aggregation and secretion of 14C-serotonin and platelet factor 4 by soluble and fibrillar collagen, respectively, were studied in human platelet-rich plasma. Neutralization of polar groups by 1) totally abolished aggregation and secretion by both collagens, while blocking acidic groups 2) resulted in enhanced aggregation and secretion by both soluble and fibrillar collagen. Blockage of amino groups by 3) abolished aggregation and secretion by both collagens. Esterified succinylated collagen 4) caused aggregation and secretion at relatively high collagen concentrations. These data support the theory that positive groups of collagen are important in platelet-collagen interaction. Images Figure 1 PMID:6881287

  18. Solar radiation absorbing material

    DOEpatents

    Googin, John M.; Schmitt, Charles R.; Schreyer, James M.; Whitehead, Harlan D.

    1977-01-01

    Solar energy absorbing means in solar collectors are provided by a solar selective carbon surface. A solar selective carbon surface is a microporous carbon surface having pores within the range of 0.2 to 2 micrometers. Such a surface is provided in a microporous carbon article by controlling the pore size. A thermally conductive substrate is provided with a solar selective surface by adhering an array of carbon particles in a suitable binder to the substrate, a majority of said particles having diameters within the range of about 0.2-10 microns.

  19. Absorber for solar power.

    PubMed

    Powell, W R

    1974-10-01

    A simple, economical absorber utilizing a new principle of operation to achieve very low reradiation losses while generating temperatures limited by material properties of quartz is described. Its performance is analyzed and indicates approximately 90% thermal efficiency and 73% conversion efficiency for an earth based unit with moderately concentrated (~tenfold) sunlight incident. It is consequently compatible with the most economic of concentrator mirrors (stamped) or mirrors deployable in space. Space applications are particularly attractive, as temperatures significantly below 300 K are possible and permit even higher conversion efficiency.

  20. Comparative study of texture of normal and energy reduced sponge cakes.

    PubMed

    Baeva, M R; Panchev, I N; Terzieva, V V

    2000-08-01

    The complete sucrose elimination and its replacement by microencapsulated aspartame (Nutra Sweet) and bulking agents (sorbitol, wheat starch and wheat germ) on the physical and textural sensory characteristics of two diabetic sponge cakes against a control sponge cake was studied. Mathematical and statistical methods were used and regression models worked out, describing the physical and textural characteristics of the three sponge cakes and their values were optimized. The effect on the porosity, springiness, volume and shrinkage of sponge takes was substantial and depended on the amount of the added ingredients. The diabetic sponge cake containing wheat germ showed the least physical and sensory deviations against the control sponge cake. The energy value of the diabetic sponge cakes against the control one was reduced with 25% for the ordinary sponge cake without sucrose and with 29% for sponge cake without sucrose containing wheat germ.

  1. Call to protect deep-sea coral, sponge ecosystems

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2004-03-01

    More than 1100 scientists are signatories to a 15 February consensus statement calling for the protection of deep sea coral and sponge ecosystems. The statement indicates that ``the greatest human threat'' to these ecosystems ``is commercial fishing, especially bottom trawling.''

  2. Diversity, structure and convergent evolution of the global sponge microbiome

    PubMed Central

    Thomas, Torsten; Moitinho-Silva, Lucas; Lurgi, Miguel; Björk, Johannes R.; Easson, Cole; Astudillo-García, Carmen; Olson, Julie B.; Erwin, Patrick M.; López-Legentil, Susanna; Luter, Heidi; Chaves-Fonnegra, Andia; Costa, Rodrigo; Schupp, Peter J.; Steindler, Laura; Erpenbeck, Dirk; Gilbert, Jack; Knight, Rob; Ackermann, Gail; Victor Lopez, Jose; Taylor, Michael W.; Thacker, Robert W.; Montoya, Jose M.; Hentschel, Ute; Webster, Nicole S.

    2016-01-01

    Sponges (phylum Porifera) are early-diverging metazoa renowned for establishing complex microbial symbioses. Here we present a global Porifera microbiome survey, set out to establish the ecological and evolutionary drivers of these host–microbe interactions. We show that sponges are a reservoir of exceptional microbial diversity and major contributors to the total microbial diversity of the world's oceans. Little commonality in species composition or structure is evident across the phylum, although symbiont communities are characterized by specialists and generalists rather than opportunists. Core sponge microbiomes are stable and characterized by generalist symbionts exhibiting amensal and/or commensal interactions. Symbionts that are phylogenetically unique to sponges do not disproportionally contribute to the core microbiome, and host phylogeny impacts complexity rather than composition of the symbiont community. Our findings support a model of independent assembly and evolution in symbiont communities across the entire host phylum, with convergent forces resulting in analogous community organization and interactions. PMID:27306690

  3. Carbon nanotube sponges as tunable materials for electromagnetic applications.

    PubMed

    Shuba, Mikhail; Yuko, Dzmitry; Kuzhir, Polina; Maksimenko, Sergey A; De Crescenzi, Maurizio; Scarselli, Manuela

    2018-06-26

    The microwave conductivity and permittivity of both single-walled and multi-walled carbon nanotube (SWCNT and MWCNT) sponges were measured while compressing the samples. Compression leads to a huge variation of the absorptance, reflectance, and transmittance of the samples. The dependence of the microwave conductivity on the sponge density follows a power-law relation with exponents 1.7±0.1 and 2.0±0.2 for MWCNT and SWCNT sponges, respectively. These exponents can be decreased slightly by the addition of a nonconducting component which partly electrically separates adjacent tubes within the samples. The conductivity of MWCNT sponge was measured in the terahertz range while heating in air from 300 K to 513 K and it increased due to an increase of a number of conducting channels in MWCNTs. © 2018 IOP Publishing Ltd.

  4. Collagenous gastritis and collagenous colitis: a report with sequential histological and ultrastructural findings

    PubMed Central

    Pulimood, A; Ramakrishna, B; Mathan, M

    1999-01-01

    The case is reported of a young adult man with collagenous gastritis, an extremely rare disorder with only three case reports in the English literature, who subsequently presented with collagenous colitis. Sequential gastric biopsies showed a notable increase in thickness of the subepithelial collagen band. Ultrastructural study of gastric and rectal mucosa showed the characteristic subepithelial band composed of haphazardly arranged collagen fibres, prominent degranulating eosinophils, and activated pericryptal fibroblasts.


Keywords: collagenous gastritis; collagenous colitis; stomach; colon PMID:10323893

  5. Combination of Root Surface Modification with BMP-2 and Collagen Hydrogel Scaffold Implantation for Periodontal Healing in Beagle Dogs

    PubMed Central

    Kato, Akihito; Miyaji, Hirofumi; Ishizuka, Ryosuke; Tokunaga, Keisuke; Inoue, Kana; Kosen, Yuta; Yokoyama, Hiroyuki; Sugaya, Tsutomu; Tanaka, Saori; Sakagami, Ryuji; Kawanami, Masamitsu

    2015-01-01

    Objective : Biomodification of the root surface plays a major role in periodontal wound healing. Root surface modification with bone morphogenetic protein (BMP) stimulates bone and cementum-like tissue formation; however, severe ankylosis is simultaneously observed. Bio-safe collagen hydrogel scaffolds may therefore be useful for supplying periodontal ligament cells and preventing ankylosis. We examined the effects of BMP modification in conjunction with collagen hydrogel scaffold implantation on periodontal wound healing in dogs. Material and Methods: The collagen hydrogel scaffold was composed of type I collagen sponge and collagen hydrogel. One-wall infrabony defects (5 mm in depth, 3 mm in width) were surgically created in six beagle dogs. In the BMP/Col group, BMP-2 was applied to the root surface (loading dose; 1 µg/µl), and the defects were filled with collagen hydrogel scaffold. In the BMP or Col group, BMP-2 coating or scaffold implantation was performed. Histometric parameters were evaluated at 4 weeks after surgery. Results: Single use of BMP stimulated formation of alveolar bone and ankylosis. In contrast, the BMP/Col group frequently enhanced reconstruction of periodontal attachment including cementum-like tissue, periodontal ligament and alveolar bone. The amount of new periodontal ligament in the BMP/Col group was significantly greater when compared to all other groups. In addition, ankylosis was rarely observed in the BMP/Col group. Conclusion: The combination method using root surface modification with BMP and collagen hydrogel scaffold implantation facilitated the reestablishment of periodontal attachment. BMP-related ankylosis was suppressed by implantation of collagen hydrogel. PMID:25674172

  6. Identification Sponges-Associated Fungi From Karimunjawa National Park

    NASA Astrophysics Data System (ADS)

    Trianto, Agus; Sabdono, Agus; Rochaddi, Baskoro; Wulan Triningsih, Desy; Seswita Zilda, Dewi

    2018-02-01

    Marine sponges are rich sources of bioactive substances with various pharmacological activities. Previous studies have shown that most bioactive compounds were originally produced by associated-microorganisms. Fungi associated with the marine sponges collected off Karimunjawa National Park were isolated and identified by morphological characteristics and molecular level analyses based on internal transcribed spacer (ITS) regions. A total of 2 isolates which were characterized, the fungi Penicillium spinulosum and Trichoderma virens have been revealed.

  7. Enhanced stabilization of collagen by furfural.

    PubMed

    Lakra, Rachita; Kiran, Manikantan Syamala; Usha, Ramamoorthy; Mohan, Ranganathan; Sundaresan, Raja; Korrapati, Purna Sai

    2014-04-01

    Furfural (2-furancarboxaldehyde), a product derived from plant pentosans, has been investigated for its interaction with collagen. Introduction of furfural during fibril formation enhanced the thermal and mechanical stability of collagen. Collagen films treated with furfural exhibited higher denaturation temperature (Td) (p<0.04) and showed a 3-fold increase in Young's modulus (p<0.04) at higher concentration. Furfural and furfural treated collagen films did not have any cytotoxic effect. Rheological characterization showed an increase in shear stress and shear viscosity with increasing shear rate for treated collagen. Circular dichroism (CD) studies indicated that the furfural did not have any impact on triple helical structure of collagen. Scanning electron microscopy (SEM) of furfural treated collagen exhibited small sized porous structure in comparison with untreated collagen. Thus this study provides an alternate ecologically safe crosslinking agent for improving the stability of collagen for biomedical and industrial applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. High-performance nanostructured supercapacitors on a sponge.

    PubMed

    Chen, Wei; Rakhi, R B; Hu, Liangbing; Xie, Xing; Cui, Yi; Alshareef, H N

    2011-12-14

    A simple and scalable method has been developed to fabricate nanostructured MnO2-carbon nanotube (CNT)-sponge hybrid electrodes. A novel supercapacitor, henceforth referred to as "sponge supercapacitor", has been fabricated using these hybrid electrodes with remarkable performance. A specific capacitance of 1,230 F/g (based on the mass of MnO2) can be reached. Capacitors based on CNT-sponge substrates (without MnO2) can be operated even under a high scan rate of 200 V/s, and they exhibit outstanding cycle performance with only 2% degradation after 100,000 cycles under a scan rate of 10 V/s. The MnO2-CNT-sponge supercapacitors show only 4% of degradation after 10,000 cycles at a charge-discharge specific current of 5 A/g. The specific power and energy of the MnO2-CNT-sponge supercapacitors are high with values of 63 kW/kg and 31 Wh/kg, respectively. The attractive performances exhibited by these sponge supercapacitors make them potentially promising candidates for future energy storage systems.

  9. Osteogenic differentiation of preosteoblasts on a hemostatic gelatin sponge

    PubMed Central

    Kuo, Zong-Keng; Lai, Po-Liang; Toh, Elsie Khai-Woon; Weng, Cheng-Hsi; Tseng, Hsiang-Wen; Chang, Pei-Zen; Chen, Chih-Chen; Cheng, Chao-Min

    2016-01-01

    Bone tissue engineering provides many advantages for repairing skeletal defects. Although many different kinds of biomaterials have been used for bone tissue engineering, safety issues must be considered when using them in a clinical setting. In this study, we examined the effects of using a common clinical item, a hemostatic gelatin sponge, as a scaffold for bone tissue engineering. The use of such a clinically acceptable item may hasten the translational lag from laboratory to clinical studies. We performed both degradation and biocompatibility studies on the hemostatic gelatin sponge, and cultured preosteoblasts within the sponge scaffold to demonstrate its osteogenic differentiation potential. In degradation assays, the gelatin sponge demonstrated good stability after being immersed in PBS for 8 weeks (losing only about 10% of its net weight and about 54% decrease of mechanical strength), but pepsin and collagenases readily biodegraded it. The gelatin sponge demonstrated good biocompatibility to preosteoblasts as demonstrated by MTT assay, confocal microscopy, and scanning electron microscopy. Furthermore, osteogenic differentiation and the migration of preosteoblasts, elevated alkaline phosphatase activity, and in vitro mineralization were observed within the scaffold structure. Each of these results indicates that the hemostatic gelatin sponge is a suitable scaffold for bone tissue engineering. PMID:27616161

  10. Gene Expression Dynamics Accompanying the Sponge Thermal Stress Response.

    PubMed

    Guzman, Christine; Conaco, Cecilia

    2016-01-01

    Marine sponges are important members of coral reef ecosystems. Thus, their responses to changes in ocean chemistry and environmental conditions, particularly to higher seawater temperatures, will have potential impacts on the future of these reefs. To better understand the sponge thermal stress response, we investigated gene expression dynamics in the shallow water sponge, Haliclona tubifera (order Haplosclerida, class Demospongiae), subjected to elevated temperature. Using high-throughput transcriptome sequencing, we show that these conditions result in the activation of various processes that interact to maintain cellular homeostasis. Short-term thermal stress resulted in the induction of heat shock proteins, antioxidants, and genes involved in signal transduction and innate immunity pathways. Prolonged exposure to thermal stress affected the expression of genes involved in cellular damage repair, apoptosis, signaling and transcription. Interestingly, exposure to sublethal temperatures may improve the ability of the sponge to mitigate cellular damage under more extreme stress conditions. These insights into the potential mechanisms of adaptation and resilience of sponges contribute to a better understanding of sponge conservation status and the prediction of ecosystem trajectories under future climate conditions.

  11. Interpreting environmental signals from the coralline sponge Astrosclera willeyana

    SciTech Connect

    Fallon, S J; McCulloch, M T; Guilderson, T P

    2004-06-30

    Coralline sponges (sclerosponges) have been proposed as a new source for paleo subsurface temperature reconstructions by utilizing methods developed for reef-building corals. However unlike corals, coralline sponges do not have density variations making age determination difficult. In this study we examined multiple elemental rations (B, Mg, Sr, Ba, U) in the coralline sponge Astrosclera willeyana. We also measured skeletal density profiles along the outer ''living'' edge of the sponges and this data indicates significant thickening of skeletal material over intervals of 2-3 mm or 2-3 years. This suggests that any skeletal recovered environmental record from Astrosclera willeyana is an integrationmore » of signals over a 2-3 year period. Sponge Sr/Ca seemed to hold the most promise as a recorder of water temperature and we compared Sr/Ca from 2 sponges in the Great Barrier Reef and one from Truk in Micronesia to their respective sea surface temperature record. The correlations were not that strong ({approx} r=-0.5) but they were significant. It appears that the signal smoothing due to thickening or perhaps even some biologic control on Sr skeletal partitioning limits the use of Sr/Ca as an indicator of water temperature in Astrosclera willeyana.« less

  12. Metamaterial electromagnetic wave absorbers.

    PubMed

    Watts, Claire M; Liu, Xianliang; Padilla, Willie J

    2012-06-19

    The advent of negative index materials has spawned extensive research into metamaterials over the past decade. Metamaterials are attractive not only for their exotic electromagnetic properties, but also their promise for applications. A particular branch-the metamaterial perfect absorber (MPA)-has garnered interest due to the fact that it can achieve unity absorptivity of electromagnetic waves. Since its first experimental demonstration in 2008, the MPA has progressed significantly with designs shown across the electromagnetic spectrum, from microwave to optical. In this Progress Report we give an overview of the field and discuss a selection of examples and related applications. The ability of the MPA to exhibit extreme performance flexibility will be discussed and the theory underlying their operation and limitations will be established. Insight is given into what we can expect from this rapidly expanding field and future challenges will be addressed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Deposition of shallow water sponges in response to seasonal changes

    NASA Astrophysics Data System (ADS)

    Ávila, Enrique; Carballo, José Luis; Vega, Cristina; Camacho, Leonardo; Barrón-Álvarez, José J.; Padilla-Verdín, Claudia; Yáñez-Chávez, Benjamín

    2011-08-01

    Removal of organisms from the subtidal zone plays an important role in shaping benthic communities in shallow bays. The main objective of this research was to quantify the biomass of sponges washed up on the beach at Mazatlan Bay (Mexico, eastern Pacific Ocean), and to determine its relationship with local weather and oceanographic conditions. To know whether this process has a significant effect on the sponge populations, changes in abundance of the species washed into the beach were also quantified in adjoining sublittoral areas. The sponges that were washed ashore were mainly branching ( Mycale ramulosa), massive ( Haliclona caerulea) and cushion-shaped ( Callyspongia californica) species. Species with high content of spongin in their structure (e.g. Hyattella intestinalis) were common in the subtidal zone but were rarely found on the beach. Encrusting species were never found. Four-year data of sponge deposition on the beach showed that the total annual sponge biomass ranged from 30 to 60 g DW m - 2 with an inter-annual range from 0.1 to 17.3 g DW m - 2 . The highest deposition of sponges was during the spring-summer transition (from April to July), which was associated with a change in wind direction (from NW to WSW). This change also matched with low tides and a high resuspension of bottom sediments, suggesting a high-energy environment during this transition. The increase in sponge biomass washed on the beach coincided with a decrease in the density of adjacent sponge populations. A multiple regression analysis showed that 68.48% of the variation on sponge biomass on the beach could be statistically explained using a combination of environmental factors (wind speed, sediment resuspension and tides). Thus, seasonal changes in wind direction combined with the effect of low tides and sediment resuspension could serve to predict fragmentation/detachment events of benthic organisms in shallow sublittoral areas worldwide. This study also provides insights to

  14. Repair of orbital floor fractures with absorbable gelatin film.

    PubMed

    Mermer, R W; Orban, R E

    1995-01-01

    Many materials have been utilized for the repair of orbital floor fractures. Absorbable gelatin film is a bioabsorbable sheeting material that is manufactured from denatured collagen. This material is appropriate for the repair of smaller orbital floor defects (5 mm or less) and trapdoor-type fractures; it is used with larger defects as an interpositional graft material between the periorbital tissues and as an orbital floor reconstruction plate or mesh. Sixteen cases consisting of both types of defects were retrospectively examined clinically and radiographically. Satisfactory results were obtained in all of these cases, including no adverse ocular signs or implant rejection, good facial form, good function, and acceptable postoperative radiography results.

  15. Collagen crosslinks in chondromalacia of the patella.

    PubMed

    Väätäinen, U; Kiviranta, I; Jaroma, H; Arokosi, J; Tammi, M; Kovanen, V

    1998-02-01

    The aim of the study was to determine collagen concentration and collagen crosslinks in cartilage samples from chondromalacia of the patella. To study the extracellular matrix alterations associated to chondromalacia, we determined the concentration of collagen (hydroxyproline) and its hydroxylysylpyridinoline and lysylpyridinoline crosslinks from chondromalacia foci of the patellae in 12 patients and 7 controls from apparently normal cadavers. The structure of the collagen network in 8 samples of grades II-IV chondromalacia was examined under polarized light microscopy. The full-thickness cartilage samples taken with a surgical knife from chondromalacia lesions did not show changes in collagen, hydroxylysylpyridinoline and lysylpyridinoline concentration as compared with the controls. Polarized light microscopy showed decreased birefringence in the superficial cartilage of chondromalacia lesions, indicating disorganization or disappearance of collagen fibers in this zone. It is concluded that the collagen network shows gradual disorganization with the severity of chondromalacia lesion of the patella without changes in the concentration or crosslinks of collagen.

  16. Reflection measurements of microwave absorbers

    NASA Astrophysics Data System (ADS)

    Baker, Dirk E.; van der Neut, Cornelis A.

    1988-12-01

    A swept-frequency interferometer is described for making rapid, real-time assessments of localized inhomogeneities in planar microwave absorber panels. An aperture-matched exponential horn is used to reduce residual reflections in the system to about -37 dB. This residual reflection is adequate for making comparative measurements on planar absorber panels whose reflectivities usually fall in the -15 to -25 dB range. Reflectivity measurements on a variety of planar absorber panels show that multilayer Jaumann absorbers have the greatest inhomogeneity, while honeycomb absorbers generally have excellent homogeneity within a sheet and from sheet to sheet. The test setup is also used to measure the center frequencies of resonant absorbers. With directional couplers and aperture-matched exponential horns, the technique can be easily applied in the standard 2 to 40 GHz waveguide bands.

  17. Antibacterial and antibiotic potentiating activities of tropical marine sponge extracts.

    PubMed

    Beesoo, Rima; Bhagooli, Ranjeet; Neergheen-Bhujun, Vidushi S; Li, Wen-Wu; Kagansky, Alexander; Bahorun, Theeshan

    2017-06-01

    Increasing prevalence of antibiotic resistance has led research to focus on discovering new antimicrobial agents derived from the marine biome. Although ample studies have investigated sponges for their bioactive metabolites with promising prospects in drug discovery, the potentiating effects of sponge extracts on antibiotics still remains to be expounded. The present study aimed to investigate the antibacterial capacity of seven tropical sponges collected from Mauritian waters and their modulatory effect in association with three conventional antibiotics namely chloramphenicol, ampicillin and tetracycline. Disc diffusion assay was used to determine the inhibition zone diameter (IZD) of the sponge total crude extracts (CE), hexane (HF), ethyl acetate (EAF) and aqueous (AF) fractions against nine standard bacterial isolates whereas broth microdilution method was used to determine their minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs) and antibiotic potentiating activity of the most active sponge extract. MIC values of the sponge extracts ranged from 0.039 to 1.25mg/mL. Extracts from Neopetrosia exigua rich in beta-sitosterol and cholesterol displayed the widest activity spectrum against the 9 tested bacterial isolates whilst the best antibacterial profile was observed by its EAF particularly against Staphylococcus aureus and Bacillus cereus with MIC and MBC values of 0.039mg/mL and 0.078mg/mL, respectively. The greatest antibiotic potentiating effect was obtained with the EAF of N. exigua (MIC/2) and ampicillin combination against S. aureus. These findings suggest that the antibacterial properties of the tested marine sponge extracts may provide an alternative and complementary strategy to manage bacterial infections. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Sterol and genomic analyses validate the sponge biomarker hypothesis.

    PubMed

    Gold, David A; Grabenstatter, Jonathan; de Mendoza, Alex; Riesgo, Ana; Ruiz-Trillo, Iñaki; Summons, Roger E

    2016-03-08

    Molecular fossils (or biomarkers) are key to unraveling the deep history of eukaryotes, especially in the absence of traditional fossils. In this regard, the sterane 24-isopropylcholestane has been proposed as a molecular fossil for sponges, and could represent the oldest evidence for animal life. The sterane is found in rocks ∼650-540 million y old, and its sterol precursor (24-isopropylcholesterol, or 24-ipc) is synthesized today by certain sea sponges. However, 24-ipc is also produced in trace amounts by distantly related pelagophyte algae, whereas only a few close relatives of sponges have been assayed for sterols. In this study, we analyzed the sterol and gene repertoires of four taxa (Salpingoeca rosetta, Capsaspora owczarzaki, Sphaeroforma arctica, and Creolimax fragrantissima), which collectively represent the major living animal outgroups. We discovered that all four taxa lack C30 sterols, including 24-ipc. By building phylogenetic trees for key enzymes in 24-ipc biosynthesis, we identified a candidate gene (carbon-24/28 sterol methyltransferase, or SMT) responsible for 24-ipc production. Our results suggest that pelagophytes and sponges independently evolved C30 sterol biosynthesis through clade-specific SMT duplications. Using a molecular clock approach, we demonstrate that the relevant sponge SMT duplication event overlapped with the appearance of 24-isopropylcholestanes in the Neoproterozoic, but that the algal SMT duplication event occurred later in the Phanerozoic. Subsequently, pelagophyte algae and their relatives are an unlikely alternative to sponges as a source of Neoproterozoic 24-isopropylcholestanes, consistent with growing evidence that sponges evolved long before the Cambrian explosion ∼542 million y ago.

  19. Sterol and genomic analyses validate the sponge biomarker hypothesis

    PubMed Central

    Gold, David A.; Grabenstatter, Jonathan; de Mendoza, Alex; Riesgo, Ana; Ruiz-Trillo, Iñaki

    2016-01-01

    Molecular fossils (or biomarkers) are key to unraveling the deep history of eukaryotes, especially in the absence of traditional fossils. In this regard, the sterane 24-isopropylcholestane has been proposed as a molecular fossil for sponges, and could represent the oldest evidence for animal life. The sterane is found in rocks ∼650–540 million y old, and its sterol precursor (24-isopropylcholesterol, or 24-ipc) is synthesized today by certain sea sponges. However, 24-ipc is also produced in trace amounts by distantly related pelagophyte algae, whereas only a few close relatives of sponges have been assayed for sterols. In this study, we analyzed the sterol and gene repertoires of four taxa (Salpingoeca rosetta, Capsaspora owczarzaki, Sphaeroforma arctica, and Creolimax fragrantissima), which collectively represent the major living animal outgroups. We discovered that all four taxa lack C30 sterols, including 24-ipc. By building phylogenetic trees for key enzymes in 24-ipc biosynthesis, we identified a candidate gene (carbon-24/28 sterol methyltransferase, or SMT) responsible for 24-ipc production. Our results suggest that pelagophytes and sponges independently evolved C30 sterol biosynthesis through clade-specific SMT duplications. Using a molecular clock approach, we demonstrate that the relevant sponge SMT duplication event overlapped with the appearance of 24-isopropylcholestanes in the Neoproterozoic, but that the algal SMT duplication event occurred later in the Phanerozoic. Subsequently, pelagophyte algae and their relatives are an unlikely alternative to sponges as a source of Neoproterozoic 24-isopropylcholestanes, consistent with growing evidence that sponges evolved long before the Cambrian explosion ∼542 million y ago. PMID:26903629

  20. Imaging Prostate Cancer Microenvironment by Collagen Hybridization

    DTIC Science & Technology

    2015-10-01

    expected to exhibit selective affinity to metastatic PCa tumors known to contain processed and denatured collagens. The motivating hypothesis is that the...CMP’s ability to bind to collagen/ denatured collagen can be used to image PCa in vivo as well as to determine the level of PCa malignancy. 15...targeted by antibodies (monoclonal antibody raised against denatured collagen); however antibodies have poor pharmacokinetics for in vivo imaging2. Recently

  1. Synthesis of reduced collagen crosslinks.

    PubMed

    van den Nieuwendijk, A M; Benningshof, J C; Wegmann, V; Bank, R A; te Koppele, J M; Brussee, J; van der Gen, A

    1999-06-21

    A new synthetic route to reduced collagen crosslinks (LNL and HLNL) is described in this report. It enables an enantioselective synthesis of LNL. HLNL was obtained as a mixture of two diastereoisomers. This method also provides the possibility to introduce radio-labels during the synthesis.

  2. Three-dimensional direct cell patterning in collagen hydrogels with near-infrared femtosecond laser

    PubMed Central

    Hribar, Kolin C.; Meggs, Kyle; Liu, Justin; Zhu, Wei; Qu, Xin; Chen, Shaochen

    2015-01-01

    We report a methodology for three-dimensional (3D) cell patterning in a hydrogel in situ. Gold nanorods within a cell-encapsulating collagen hydrogel absorb a focused near-infrared femtosecond laser beam, locally denaturing the collagen and forming channels, into which cells migrate, proliferate, and align in 3D. Importantly, pattern resolution is tunable based on writing speed and laser power, and high cell viability (>90%) is achieved using higher writing speeds and lower laser intensities. Overall, this patterning technique presents a flexible direct-write method that is applicable in tissue engineering systems where 3D alignment is critical (such as vascular, neural, cardiac, and muscle tissue). PMID:26603915

  3. [Morphological, optical, and structural characteristics of glass sponge spicules and the photoreceptor hypothesis of their survival].

    PubMed

    Voznesenskiĭ, S S; Kul'chin, Iu N; Galkina, A N; Sergeev, A A

    2010-01-01

    The morphology, structure, and optical characteristics of spicules of some sea glass sponges have been studied. The results obtained are interpreted from the point of view of their possible role in the survival of the organism of sponges.

  4. Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap

    MedlinePlus

    ... Education & Events Advocacy For Patients About ACOG Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and ... Cervical Cap FAQ022, March 2018 PDF Format Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and ...

  5. 21 CFR 529.1003 - Flurogestone acetate-impregnated vaginal sponge.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... into ewe's vagina 13 days before desired start of breeding. For intravaginal use in sheep only. Do not... sponges to minimize exposure to drug. Do not leave sponge in the vagina for more than 21 days. Ewes must...

  6. 21 CFR 529.1003 - Flurogestone acetate-impregnated vaginal sponge.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... into ewe's vagina 13 days before desired start of breeding. For intravaginal use in sheep only. Do not... sponges to minimize exposure to drug. Do not leave sponge in the vagina for more than 21 days. Ewes must...

  7. Contact sponge water absorption test implemented for in situ measures

    NASA Astrophysics Data System (ADS)

    Gaggero, Laura; Scrivano, Simona

    2016-04-01

    The contact sponge method is a non-destructive in-situ methodology used to estimate a water uptake coefficient. The procedure, unlike other in-situ measurement was proven to be directly comparable to the water uptake laboratory measurements, and was registered as UNI 11432:2011. The UNI Normal procedure requires to use a sponge with known density, soaked in water, weighed, placed on the material for 1 minute (UNI 11432, 2011; Pardini & Tiano, 2004), then weighed again. Difficulties arise in operating on test samples or on materials with porosity varied for decay. While carrying on the test, fluctuations in the bearing of the environmental parameters were negligible, but not the pressure applied to the surface, that induced the release of different water amounts towards the material. For this reason we designed a metal piece of the same diameter of the plate carrying the sponge, to be screwed at the tip of a pocket penetrometer. With this instrument the sponge was kept in contact with the surface for 1 minute applying two different loads, at first pushed with 0.3 kg/cm2 in order to press the sponge, but not its holder, against the surface. Then, a load of 1.1 kg/ cm2 was applied, still avoiding deviating the load to the sponge holder. We applied both the current and our implemented method to determine the water absorption by contact sponge on 5 fresh rock types (4 limestones: Fine - and Coarse grained Pietra di Vicenza, Rosso Verona, Breccia Aurora, and the silicoclastic Macigno sandstone). The results show that 1) the current methodology imply manual skill and experience to produce a coherent set of data; the variable involved are in fact not only the imposed pressure but also the compression mechanics. 2) The control on the applied pressure allowed reproducible measurements. Moreover, 3) the use of a thicker sponge enabled to apply the method even on rougher surfaces, as the device holding the sponge is not in contact with the tested object. Finally, 4) the

  8. Ultralight, scalable, and high-temperature-resilient ceramic nanofiber sponges.

    PubMed

    Wang, Haolun; Zhang, Xuan; Wang, Ning; Li, Yan; Feng, Xue; Huang, Ya; Zhao, Chunsong; Liu, Zhenglian; Fang, Minghao; Ou, Gang; Gao, Huajian; Li, Xiaoyan; Wu, Hui

    2017-06-01

    Ultralight and resilient porous nanostructures have been fabricated in various material forms, including carbon, polymers, and metals. However, the development of ultralight and high-temperature resilient structures still remains extremely challenging. Ceramics exhibit good mechanical and chemical stability at high temperatures, but their brittleness and sensitivity to flaws significantly complicate the fabrication of resilient porous ceramic nanostructures. We report the manufacturing of large-scale, lightweight, high-temperature resilient, three-dimensional sponges based on a variety of oxide ceramic (for example, TiO 2 , ZrO 2 , yttria-stabilized ZrO 2 , and BaTiO 3 ) nanofibers through an efficient solution blow-spinning process. The ceramic sponges consist of numerous tangled ceramic nanofibers, with densities varying from 8 to 40 mg/cm 3 . In situ uniaxial compression in a scanning electron microscope showed that the TiO 2 nanofiber sponge exhibits high energy absorption (for example, dissipation of up to 29.6 mJ/cm 3 in energy density at 50% strain) and recovers rapidly after compression in excess of 20% strain at both room temperature and 400°C. The sponge exhibits excellent resilience with residual strains of only ~1% at 800°C after 10 cycles of 10% compression strain and maintains good recoverability after compression at ~1300°C. We show that ceramic nanofiber sponges can serve multiple functions, such as elasticity-dependent electrical resistance, photocatalytic activity, and thermal insulation.

  9. Advancement into the Arctic Region for Bioactive Sponge Secondary Metabolites

    PubMed Central

    Abbas, Samuel; Kelly, Michelle; Bowling, John; Sims, James; Waters, Amanda; Hamann, Mark

    2011-01-01

    Porifera have long been a reservoir for the discovery of bioactive compounds and drug discovery. Most research in the area has focused on sponges from tropical and temperate waters, but more recently the focus has shifted to the less accessible colder waters of the Antarctic and, to a lesser extent, the Arctic. The Antarctic region in particular has been a more popular location for natural products discovery and has provided promising candidates for drug development. This article reviews groups of bioactive compounds that have been isolated and reported from the southern reaches of the Arctic Circle, surveys the known sponge diversity present in the Arctic waters, and details a recent sponge collection by our group in the Aleutian Islands, Alaska. The collection has yielded previously undescribed sponge species along with primary activity against opportunistic infectious diseases, malaria, and HCV. The discovery of new sponge species and bioactive crude extracts gives optimism for the isolation of new bioactive compounds from a relatively unexplored source. PMID:22163194

  10. Bleaching and recovery of a phototrophic bioeroding sponge

    NASA Astrophysics Data System (ADS)

    Marlow, Joseph; Davy, Simon K.; Shaffer, Megan; Haris, Abdul; Bell, James J.

    2018-06-01

    In the Wakatobi region of Indonesia, a prolonged period of elevated water temperature in 2016 caused extensive coral bleaching and mortality. Unusually, bleaching was also observed in the bioeroding sponge Cliona aff. viridis, with affected sponges expelling 99% of their Symbiodinium. Bleaching surveys of C. aff. viridis were conducted 6 weeks apart, coinciding with a 0.8 °C drop in water temperature. Over this period, bleaching prevalence dropped from 73.9% (± 9.9 SE) to 25.7% (± 5.8 SE), and bleaching severity dropped from 25.95% (± 4.5 SE) to 11.54% (± 1.9 SE) of sponge tissue. Over the same period, monitored bleached sponges showed an 81% drop in bleaching severity, but also a 13% reduction in overall sponge size. Our results show that while the clionaid- Symbiodinium relationship is susceptible to break down under thermal stress, rapid recovery can occur, although incurring some partial host mortality.

  11. Ultralight, scalable, and high-temperature–resilient ceramic nanofiber sponges

    PubMed Central

    Wang, Haolun; Zhang, Xuan; Wang, Ning; Li, Yan; Feng, Xue; Huang, Ya; Zhao, Chunsong; Liu, Zhenglian; Fang, Minghao; Ou, Gang; Gao, Huajian; Li, Xiaoyan; Wu, Hui

    2017-01-01

    Ultralight and resilient porous nanostructures have been fabricated in various material forms, including carbon, polymers, and metals. However, the development of ultralight and high-temperature resilient structures still remains extremely challenging. Ceramics exhibit good mechanical and chemical stability at high temperatures, but their brittleness and sensitivity to flaws significantly complicate the fabrication of resilient porous ceramic nanostructures. We report the manufacturing of large-scale, lightweight, high-temperature resilient, three-dimensional sponges based on a variety of oxide ceramic (for example, TiO2, ZrO2, yttria-stabilized ZrO2, and BaTiO3) nanofibers through an efficient solution blow-spinning process. The ceramic sponges consist of numerous tangled ceramic nanofibers, with densities varying from 8 to 40 mg/cm3. In situ uniaxial compression in a scanning electron microscope showed that the TiO2 nanofiber sponge exhibits high energy absorption (for example, dissipation of up to 29.6 mJ/cm3 in energy density at 50% strain) and recovers rapidly after compression in excess of 20% strain at both room temperature and 400°C. The sponge exhibits excellent resilience with residual strains of only ~1% at 800°C after 10 cycles of 10% compression strain and maintains good recoverability after compression at ~1300°C. We show that ceramic nanofiber sponges can serve multiple functions, such as elasticity-dependent electrical resistance, photocatalytic activity, and thermal insulation. PMID:28630915

  12. Soaking it up: new lipid sponge phases and their applications

    NASA Astrophysics Data System (ADS)

    Brasnett, Christopher; Seddon, Annela

    Recent work has demonstrated that cubic lipid systems may be doped with charged lipids, with important consequences for their physical properties. Among others, Tyler et al. have reported some of the largest lipid cubic phases seen to date using this technique. The sponge phase is a disordered bicontinuous phase, formed when the membrane curvature of a cubic phase is reduced through the addition of butane diol. Additionally, it is known that sponge phases may be converted back into highly ordered cubic ones. Whilst past work has concentrated on sponge phases formed from monoolein, we have investigated the properties and behaviour of a bipartite sponge phase formed of monoolein and DOPG, and their conversion to cubic phases using shear. Furthermore, as both the sponge and cubic phase are of interest with respect to their applications in protein crystallography, we have explored the interaction of the protein light-harvesting complex with the lipid system. CB is supported by a University of Bristol EPSRC funded studentship.

  13. Microbiological Safety of Kitchen Sponges Used in Food Establishments

    PubMed Central

    Bacha, Ketema

    2016-01-01

    Kitchen sponges are among the possible sources of contaminants in food establishments. The main purpose of the current study was, therefore, to assess the microbiological safety of sponges as it has been used in selected food establishments of Jimma town. Accordingly, the microbiological safety of a total of 201 kitchen sponges randomly collected from food establishments was evaluated against the total counts of aerobic mesophilic bacteria (AMB), Enterobacteriaceae, coliforms, and yeast and molds. The mean counts of aerobic mesophilic bacteria ranged from 7.43 to 12.44 log CFU/mm3. The isolated genera were dominated by Pseudomonas (16.9%), Bacillus (11.1%), Micrococcus (10.6%), Streptococcus (7.8%), and Lactobacillus (6%) excluding the unidentified Gram positive rods (4.9%) and Gram negative rods (9.9%). The high microbial counts (aerobic mesophilic bacteria, coliforms, Enterobacteriaceae, and yeast and molds) reveal the existence of poor kitchen sponge sanitization practice. Awareness creation training on basic hygienic practices to food handlers and periodic change of kitchen sponges are recommended. PMID:27840819

  14. Physicochemical properties of 3D collagen-CS scaffolds for potential use in neural tissue engineering.

    PubMed

    Pietrucha, Krystyna

    2015-09-01

    Collagen-based composite scaffolds have considerable potential due to their well-known ability to regenerate skin, bone and cartilage. However, the precise composition and structure of scaffolds that optimize their interaction with neural cells remains incompletely understood and yet to be explored. In the present study, a new family of bi-component 3D scaffolds consisting of collagen (Col) and chondroitin sulphate (CS) were synthesized using a two-stage process: multiple freeze-drying followed by carbodiimide modification. Col-CS matrices had an average pore diameter of 31 μm and a relatively high surface area to pore volume ratio. Importantly, the FTIR data indicated that the ratio between the intensity of amide III and 1452 cm(-1) for Col-CS scaffold was 0.87, which indicates that the Col triple helix was preserved during the formation of the bond between Col and CS. All experiments also clearly showed that the Col-CS matrices have a lower enzyme sensitivity and higher thermal resistance than Col alone. These differences are likely due to the relatively large amount of CS in the collagen sponges, which hinders access for attack at specific active sites of the Col triple helix. Improved binary composite scaffolds were designed for neural tissue engineering applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Preparation of flexible bone tissue scaffold utilizing sea urchin test and collagen.

    PubMed

    Manchinasetty, Naga Vijaya Lakshmi; Oshima, Sho; Kikuchi, Masanori

    2017-10-13

    Gonads of sea urchin are consumed in Japan and some countries as food and most parts including its tests are discarded as marine wastes. Therefore, utilization of them as functional materials would reduce the waste as well as encourage Japanese fishery. In this study, magnesium containing calcite granules collected from sea urchin tests were hydrothermally phosphatized and the obtained granules were identified as approximately 82% in mass of magnesium containing β-tricalcium phosphate and 18% in mass of nonstoichiometric hydroxyapatite, i.e., a biphasic calcium phosphate, maintaining the original porous network. Shape-controlled scaffolds were fabricated with the obtained biphasic calcium phosphate granules and collagen. The scaffolds showed good open porosity (83.84%) and adequate mechanical properties for handling during cell culture and subsequent operations. The MG-63 cells showed higher proliferation and osteogenic differentiation in comparison to a control material, the collagen sponge with the same size. Furthermore, cell viability assay proved that the scaffolds were not cytotoxic. These results suggest that scaffold prepared using sea urchin test derived calcium phosphate and collagen could be a potential candidate of bone void fillers for non-load bearing defects in bone reconstruction as well as scaffolds for bone tissue engineering.

  16. THE GENERALIZATION OF SIERPINSKI CARPET AND MENGER SPONGE IN n-DIMENSIONAL SPACE

    NASA Astrophysics Data System (ADS)

    Yang, Yun; Feng, Yuting; Yu, Yanhua

    In this paper, we generalize Sierpinski carpet and Menger sponge in n-dimensional space, by using the generations and characterizations of affinely-equivalent Sierpinski carpet and Menger sponge. Exactly, Menger sponge in 4-dimensional space could be drawn out clearly under an affine transformation. Furthermore, the method could be used to a much broader class in fractals.

  17. A novel filtering mutualism between a sponge host and its endosymbiotic bivalves.

    PubMed

    Tsubaki, Remi; Kato, Makoto

    2014-01-01

    Sponges, porous filter-feeding organisms consisting of vast canal systems, provide unique substrates for diverse symbiotic organisms. The Spongia (Spongia) sp. massive sponge is obligately inhabited by the host-specific endosymbiotic bivalve Vulsella vulsella, which benefits from this symbiosis by receiving protection from predators. However, whether the host sponge gains any benefit from this association is unclear. Considering that the bivalves exhale filtered water into the sponge body rather than the ambient environment, the sponge is hypothesized to utilize water exhaled by the bivalves to circulate water around its body more efficiently. We tested this hypothesis by observing the sponge aquiferous structure and comparing the pumping rates of sponges and bivalves. Observations of water currents and the sponge aquiferous structure revealed that the sponge had a unique canal system enabling it to inhale water exhaled from bivalves, indicating that the host sponge adapted morphologically to receive water from the bivalves. In addition, the volume of water circulating in the sponge body was dramatically increased by the water exhaled from bivalves. Therefore, this sponge-bivalve association can be regarded as a novel mutualism in which two filter-feeding symbionts promote mutual filtering rates. This symbiotic association should be called a "filtering mutualism".

  18. The unique skeleton of siliceous sponges (Porifera; Hexactinellida and Demospongiae) that evolved first from the Urmetazoa during the Proterozoic: a review

    NASA Astrophysics Data System (ADS)

    Müller, W. E. G.; Li, J.; Schröder, H. C.; Qiao, L.; Wang, X.

    2007-02-01

    net formed of collagen fibers. The data summarized here substantiate that with the finding of silicatein a new aera in the field of bio/inorganic chemistry started. For the first time strategies could be formulated and experimentally proven that allow the formation/synthesis of inorganic structures by organic molecules. These findings are not only of importance for the further understanding of basic pathways in the body plan formation of sponges but also of eminent importance for applied/commercial processes in a sustainable use of biomolecules for novel bio/inorganic materials.

  19. The unique skeleton of siliceous sponges (Porifera; Hexactinellida and Demospongiae) that evolved first from the Urmetazoa during the Proterozoic: a review

    NASA Astrophysics Data System (ADS)

    Müller, W. E. G.; Li, Jinhe; Schröder, H. C.; Qiao, Li; Wang, Xiaohong

    2007-05-01

    Sponges (phylum Porifera) had been considered as an enigmatic phylum, prior to the analysis of their genetic repertoire/tool kit. Already with the isolation of the first adhesion molecule, galectin, it became clear that the sequences of sponge cell surface receptors and of molecules forming the intracellular signal transduction pathways triggered by them, share high similarity with those identified in other metazoan phyla. These studies demonstrated that all metazoan phyla, including Porifera, originate from one common ancestor, the Urmetazoa. The sponges evolved prior to the Ediacaran-Cambrian boundary (542 million years ago [myr]) during two major "snowball earth events", the Sturtian glaciation (710 to 680 myr) and the Varanger-Marinoan ice ages (605 to 585 myr). During this period the ocean was richer in silica due to the silicate weathering. The oldest sponge fossils (Hexactinellida) have been described from Australia, China and Mongolia and are thought to have existed coeval with the diverse Ediacara fauna. Only little younger are the fossils discovered in the Sansha section in Hunan (Early Cambrian; China). It has been proposed that only the sponges possessed the genetic repertoire to cope with the adverse conditions, e.g. temperature-protection molecules or proteins protecting them against ultraviolet radiation. The skeletal elements of the Hexactinellida (model organisms Monorhaphis chuni and Monorhaphis intermedia or Hyalonema sieboldi) and Demospongiae (models Suberites domuncula and Geodia cydonium), the spicules, are formed enzymatically by the anabolic enzyme silicatein and the catabolic enzyme silicase. Both, the spicules of Hexactinellida and of Demospongiae, comprise a central axial canal and an axial filament which harbors the silicatein. After intracellular formation of the first lamella around the channel and the subsequent extracellular apposition of further lamellae the spicules are completed in a net formed of collagen fibers. The data

  20. Three-dimensional periodic supramolecular organic framework ion sponge in water and microcrystals

    DOE PAGES

    Tian, Jia; Zhou, Tian-You; Zhang, Shao-Chen; ...

    2014-12-02

    Self-assembly has emerged as a powerful approach to generating complex supramolecular architectures. Despite there being many crystalline frameworks reported in the solid state, the construction of highly soluble periodic supramolecular networks in a three-dimensional space is still a challenge. In this paper we demonstrate that the encapsulation motif, which involves the dimerization of two aromatic units within cucurbit[8]uril, can be used to direct the co-assembly of a tetratopic molecular block and cucurbit[8]uril into a periodic three-dimensional supramolecular organic framework in water. The periodicity of the supramolecular organic framework is supported by solution-phase small-angle X-ray-scattering and diffraction experiments. Upon evaporating themore » solvent, the periodicity of the framework is maintained in porous microcrystals. Lastly, as a supramolecular 'ion sponge', the framework can absorb different kinds of anionic guests, including drugs, in both water and microcrystals, and drugs absorbed in microcrystals can be released to water with selectivity.« less

  1. Energy absorber for the CETA

    NASA Technical Reports Server (NTRS)

    Wesselski, Clarence J.

    1994-01-01

    The energy absorber that was developed for the CETA (Crew Equipment and Translation Aid) on Space Station Freedom is a metal on metal frictional type and has a load regulating feature that prevents excessive stroking loads from occurring while in operation. This paper highlights some of the design and operating aspects and the testing of this energy absorber.

  2. Metal-shearing energy absorber

    NASA Technical Reports Server (NTRS)

    Fay, R. J.; Wittrock, E. P.

    1971-01-01

    Device, consisting of tongue of thin aluminum alloy strip, pull tab, slotted steel plate which serves as cutter, and steel buckle, absorbs mechanical energy when its ends are subjected to tensile loading. Device is applicable as auxiliary shock absorbing anchor for automobile and airplane safety belts.

  3. Leaf absorbance and photosynthesis

    NASA Technical Reports Server (NTRS)

    Schurer, Kees

    1994-01-01

    The absorption spectrum of a leaf is often thought to contain some clues to the photosynthetic action spectrum of chlorophyll. Of course, absorption of photons is needed for photosynthesis, but the reverse, photosynthesis when there is absorption, is not necessarily true. As a check on the existence of absorption limits we measured spectra for a few different leaves. Two techniques for measuring absorption have been used, viz. the separate determination of the diffuse reflectance and the diffuse transmittance with the leaf at a port of an integrating sphere and the direct determination of the non-absorbed fraction with the leaf in the sphere. In a cross-check both methods yielded the same results for the absorption spectrum. The spectrum of a Fuchsia leaf, covering the short-wave region from 350 to 2500 nm, shows a high absorption in UV, blue and red, the well known dip in the green and a steep fall-off at 700 nm. Absorption drops to virtually zero in the near infrared, with subsequent absorptions, corresponding to the water absorption bands. In more detailed spectra, taken at 5 nm intervals with a 5 nm bandwidth, differences in chlorophyll content show in the different depths of the dip around 550 nm and in a small shift of the absorption edge at 700 nm. Spectra for Geranium (Pelargonium zonale) and Hibiscus (with a higher chlorophyll content) show that the upper limit for photosynthesis can not be much above 700 nm. No evidence, however, is to be seen of a lower limit for photosynthesis and, in fact, some experiments down to 300 nm still did not show a decrease of the absorption although it is well recognized that no photosynthesis results with 300 nm wavelengths.

  4. Collagens--structure, function, and biosynthesis.

    PubMed

    Gelse, K; Pöschl, E; Aigner, T

    2003-11-28

    The extracellular matrix represents a complex alloy of variable members of diverse protein families defining structural integrity and various physiological functions. The most abundant family is the collagens with more than 20 different collagen types identified so far. Collagens are centrally involved in the formation of fibrillar and microfibrillar networks of the extracellular matrix, basement membranes as well as other structures of the extracellular matrix. This review focuses on the distribution and function of various collagen types in different tissues. It introduces their basic structural subunits and points out major steps in the biosynthesis and supramolecular processing of fibrillar collagens as prototypical members of this protein family. A final outlook indicates the importance of different collagen types not only for the understanding of collagen-related diseases, but also as a basis for the therapeutical use of members of this protein family discussed in other chapters of this issue.

  5. Ferroelectric nanoparticle-embedded sponge structure triboelectric generators

    NASA Astrophysics Data System (ADS)

    Park, Daehoon; Shin, Sung-Ho; Yoon, Ick-Jae; Nah, Junghyo

    2018-05-01

    We report high-performance triboelectric nanogenerators (TENGs) employing ferroelectric nanoparticles (NPs) embedded in a sponge structure. The ferroelectric BaTiO3 NPs inside the sponge structure play an important role in increasing surface charge density by polarized spontaneous dipoles, enabling the packaging of TENGs even with a minimal separation gap. Since the friction surfaces are encapsulated in the packaged device structure, it suffers negligible performance degradation even at a high relative humidity of 80%. The TENGs also demonstrated excellent mechanical durability due to the elasticity and flexibility of the sponge structure. Consequently, the TENGs can reliably harvest energy even under harsh conditions. The approach introduced here is a simple, effective, and reliable way to fabricate compact and packaged TENGs for potential applications in wearable energy-harvesting devices.

  6. Ferroelectric nanoparticle-embedded sponge structure triboelectric generators.

    PubMed

    Park, Daehoon; Shin, Sung-Ho; Yoon, Ick-Jae; Nah, Junghyo

    2018-05-04

    We report high-performance triboelectric nanogenerators (TENGs) employing ferroelectric nanoparticles (NPs) embedded in a sponge structure. The ferroelectric BaTiO 3 NPs inside the sponge structure play an important role in increasing surface charge density by polarized spontaneous dipoles, enabling the packaging of TENGs even with a minimal separation gap. Since the friction surfaces are encapsulated in the packaged device structure, it suffers negligible performance degradation even at a high relative humidity of 80%. The TENGs also demonstrated excellent mechanical durability due to the elasticity and flexibility of the sponge structure. Consequently, the TENGs can reliably harvest energy even under harsh conditions. The approach introduced here is a simple, effective, and reliable way to fabricate compact and packaged TENGs for potential applications in wearable energy-harvesting devices.

  7. Brackish habitat dictates cultivable Actinobacterial diversity from marine sponges

    PubMed Central

    Chanana, Shaurya; Adnani, Navid; Szachowicz, Emily; Braun, Doug R.; Harper, Mary Kay; Wyche, Thomas P.; Bugni, Tim S.

    2017-01-01

    Bacterial communities associated with marine invertebrates such as sponges and ascidians have demonstrated potential as sources of bio-medically relevant small molecules. Metagenomic analysis has shown that many of these invertebrates harbor populations of Actinobacteria, many of which are cultivable. While some populations within invertebrates are transmitted vertically, others are obtained from the environment. We hypothesized that cultivable diversity from sponges living in brackish mangrove habitats have associations with Actinobacterial populations that differ from those found in clear tropical waters. In this study, we analyzed the cultivable Actinobacterial populations from sponges found in these two distinct habitats with the aim of understanding the secondary metabolite potential. Importantly, we wanted to broadly evaluate the potential differences among these groups to guide future Actinobacterial collection strategies for the purposes of drug discovery. PMID:28692665

  8. Controlled iodine release from polyurethane sponges for water decontamination.

    PubMed

    Aviv, Oren; Laout, Natalia; Ratner, Stanislav; Harik, Oshrat; Kunduru, Konda Reddy; Domb, Abraham J

    2013-12-28

    Iodinated polyurethane (IPU) sponges were prepared by immersing sponges in aqueous/organic solutions of iodine or exposing sponges to iodine vapors. Iodine was readily adsorbed into the polymers up to 100% (w/w). The adsorption of iodine on the surface was characterized by XPS and SEM analyses. The iodine loaded IPU sponges were coated with ethylene vinyl acetate (EVA), in order to release iodine in a controlled rate for water decontamination combined with active carbon cartridge, which adsorbs the iodine residues after the microbial inactivation. The EVA coated IPU were incorporated in a water purifier and tested for iodine release to water and for microbial inactivation efficiency according to WQA certification program against P231/EPA for 250l, using 25l a day with flow rate of 6-8min/1l. The antimicrobial activity was also studied against Escherichia coli and MS2 phage. Bacterial results exceeded the minimal requirement for bacterial removal of 6log reduction throughout the entire lifespan. At any testing point, no bacteria was detected in the outlet achieving more than 7.1 to more than 8log reduction as calculated upon the inlet concentration. Virus surrogate, MS2, reduction results varied from 4.11log reduction under tap water, and 5.11log reduction under basic water (pH9) to 1.32 for acidic water (pH5). Controlled and stable iodine release was observed with the EVA coated IPU sponges and was effective in deactivating the bacteria and virus present in the contaminated water and thus, these iodinated PU systems could be used in water purification to provide safe drinking water. These sponges may find applications as disinfectants in medicine. © 2013.

  9. Diversity and Distribution Patterns in High Southern Latitude Sponges

    PubMed Central

    Downey, Rachel V.; Griffiths, Huw J.; Linse, Katrin; Janussen, Dorte

    2012-01-01

    Sponges play a key role in Antarctic marine benthic community structure and dynamics and are often a dominant component of many Southern Ocean benthic communities. Understanding the drivers of sponge distribution in Antarctica enables us to understand many of general benthic biodiversity patterns in the region. The sponges of the Antarctic and neighbouring oceanographic regions were assessed for species richness and biogeographic patterns using over 8,800 distribution records. Species-rich regions include the Antarctic Peninsula, South Shetland Islands, South Georgia, Eastern Weddell Sea, Kerguelen Plateau, Falkland Islands and north New Zealand. Sampling intensity varied greatly within the study area, with sampling hotspots found at the Antarctic Peninsula, South Georgia, north New Zealand and Tierra del Fuego, with limited sampling in the Bellingshausen and Amundsen seas in the Southern Ocean. In contrast to previous studies we found that eurybathy and circumpolar distributions are important but not dominant characteristics in Antarctic sponges. Overall Antarctic sponge species endemism is ∼43%, with a higher level for the class Hexactinellida (68%). Endemism levels are lower than previous estimates, but still indicate the importance of the Polar Front in isolating the Southern Ocean fauna. Nineteen distinct sponge distribution patterns were found, ranging from regional endemics to cosmopolitan species. A single, distinct Antarctic demosponge fauna is found to encompass all areas within the Polar Front, and the sub-Antarctic regions of the Kerguelen Plateau and Macquarie Island. Biogeographical analyses indicate stronger faunal links between Antarctica and South America, with little evidence of links between Antarctica and South Africa, Southern Australia or New Zealand. We conclude that the biogeographic and species distribution patterns observed are largely driven by the Antarctic Circumpolar Current and the timing of past continent connectivity. PMID

  10. Synthesis and viscoelastic characterization of microstructurally aligned Silk fibroin sponges.

    PubMed

    Panda, Debojyoti; Konar, Subhajit; Bajpai, Saumendra K; Arockiarajan, A

    2017-07-01

    Silk fibroin (SF) is a model candidate for use in tissue engineering and regenerative medicine owing to its bio-compatible mechanochemical properties. Despite numerous advances made in the fabrication of various biomimetic substrates using SF, relatively few clinical applications have been designed, primarily due to the lack of complete understanding of its constitutive properties. Here we fabricate microstructurally aligned SF sponge using the unidirectional freezing technique wherein a novel solvent-processing technique involving Acetic acid is employed, which obviates the post-treatment of the sponges to induce their water-stability. Subsequently, we quantify the anisotropic, viscoelastic response of the bulk SF sponge samples by performing a series of mechanical tests under uniaxial compression over a wide range of strain rates. Results for these uniaxial compression tests in the finite strain regime through ramp strain and ramp-relaxation loading histories applied over two orders of strain rate magnitude show that microstructural anisotropy is directly manifested in the bulk viscoelastic solid-like response. Furthermore, the experiments reveal a high degree of volume compressibility of the sponges during deformation, and also evince for their remarkable strain recovery capacity under large compressive strains during strain recovery tests. Finally, in order to predict the bulk viscoelastic material properties of the fabricated and pre-characterized SF sponges, a finite strain kinematics-based, nonlinear, continuum model developed within a thermodynamically-consistent framework in a parallel investigation, was successfully employed to capture the viscoelastic solid-like, transversely isotropic, and compressible response of the sponges macroscopically. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Structural changes in cartilage and collagen studied by high temperature Raman spectroscopy.

    PubMed

    Fields, Mark; Spencer, Nicholas; Dudhia, Jayesh; McMillan, Paul F

    2017-06-01

    Understanding the high temperature behavior of collagen and collagenous tissue is important for surgical procedures and biomaterials processing for the food, pharmaceutical, and cosmetics industries. One primary event for proteins is thermal denaturation that involves unfolding the polypeptide chains while maintaining the primary structure intact. Collagen in the extracellular matrix of cartilage and other connective tissue is a hierarchical material containing bundles of triple-helical fibers associated with water and proteoglycan components. Thermal analysis of dehydrated collagen indicates irreversible denaturation at high temperature between 135°C and 200°C, with another reversible event at ∼60-80°C for hydrated samples. We report high temperature Raman spectra for freeze-dried cartilage samples that show an increase in laser-excited fluorescence interpreted as conformational changes associated with denaturation above 140°C. Spectra for separated collagen and proteoglycan fractions extracted from cartilage indicate the changes are associated with collagen. The Raman data also show appearance of new features indicating peptide bond hydrolysis at high temperature implying that molecular H 2 O is retained within the freeze-dried tissue. This is confirmed by thermogravimetric analysis that show 5-7 wt% H 2 O remaining within freeze-dried cartilage that is released progressively upon heating up to 200°C. Spectra obtained after exposure to high temperature and re-hydration following recovery indicate that the capacity of the denatured collagen to re-absorb water is reduced. Our results are important for revealing the presence of bound H 2 O within the collagen component of connective tissue even after freeze-drying and its role in denaturation that is accompanied by or perhaps preceded by breakdown of the primary polypeptide structure. © 2017 Wiley Periodicals, Inc.

  12. Bioactive Natural Products of Marine Sponges from the Genus Hyrtios.

    PubMed

    Shady, Nourhan Hisham; El-Hossary, Ebaa M; Fouad, Mostafa A; Gulder, Tobias A M; Kamel, Mohamed Salah; Abdelmohsen, Usama Ramadan

    2017-05-11

    Marine sponges are known as a rich source for novel bioactive compounds with valuable pharmacological potential. One of the most predominant sponge genera is Hyrtios , reported to have various species such as Hyrtios erectus , Hyrtios reticulatus , Hyrtios gumminae , Hyrtios communis , and Hyrtios tubulatus and a number of undescribed species. Members of the genus Hyrtios are a rich source of natural products with diverse and valuable biological activities, represented by different chemical classes including alkaloids, sesterterpenes and sesquiterpenes. This review covers the literature until June 2016, providing a complete survey of all compounds isolated from the genus Hyrtios with their corresponding biological activities whenever applicable.

  13. Immunostimulation effect of jellyfish collagen.

    PubMed

    Sugahara, Takuya; Ueno, Masashi; Goto, Yoko; Shiraishi, Ryusuke; Doi, Mikiharu; Akiyama, Koichi; Yamauchi, Satoshi

    2006-09-01

    Certain edible large jellyfishes belonging to the order Rhizostomeae are consumed in large quantities in China and Japan. The exumbrella part of the edible jellyfish Stomolophus nomurai was cut and soaked in dilute hydrochloric acid solution (pH 3.0) for 12 h, and heated at 121 degrees C for 20 min. The immunostimulation effects of the jellyfish extract were examined. The jellyfish extract enhanced IgM production of human hybridoma HB4C5 cells 34-fold. IgM and IgG production of human peripheral blood lymphocytes (PBL) were also accelerated, 2.8- and 1.4-fold respectively. Moreover, production of interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha by human PBL was stimulated 100- and 17-fold respectively. Collagenase treatment inactivated the immunostimulation activity of the jellyfish extract. In addition, purified collagen from bovine Achilles' tendon accelerated IgM production of hybridoma cells. These facts mean that collagen has an immunostimulation effect, and that the active substance in jellyfish extract is collagen.

  14. Absorbent product to absorb fluids. [for collection of human wastes

    NASA Technical Reports Server (NTRS)

    Dawn, F. S.; Correale, J. V. (Inventor)

    1982-01-01

    A multi-layer absorbent product for use in contact with the skin to absorb fluids is discussed. The product utilizes a water pervious facing layer for contacting the skin, overlayed by a first fibrous wicking layer, the wicking layer preferably being of the one-way variety in which fluid or liquid is moved away from the facing layer. The product further includes a first container section defined by inner and outer layer of a water pervious wicking material between which is disposed a first absorbent mass. A second container section defined by inner and outer layers between which is disposed a second absorbent mass and a liquid impermeable/gas permeable layer. Spacesuit applications are discussed.

  15. Collagen telopeptides (cross-linking sites) play a role in collagen gel lattice contraction

    NASA Technical Reports Server (NTRS)

    Woodley, D. T.; Yamauchi, M.; Wynn, K. C.; Mechanic, G.; Briggaman, R. A.

    1991-01-01

    Solubilized interstitial collagens will form a fibrillar, gel-like lattice when brought to physiologic conditions. In the presence of human dermal fibroblasts the collagen lattice will contract. The rate of contraction can be determined by computer-assisted planemetry. The mechanisms involved in contraction are as yet unknown. Using this system it was found that the rate of contraction was markedly decreased when collagen lacking telopeptides was substituted for native collagen. Histidinohydroxylysinonorleucine (HHL) is a major stable trifunctional collagen cross-link in mature skin that involves a carboxyl terminal, telopeptide site 16c, the sixteenth amino acid residue from the carboxy terminal of the telopeptide region of alpha 1 (I) in type I collagen. Little, if any, HHL was present in native, purified, reconstituted, soluble collagen fibrils from 1% acetic acid-extracted 2-year-old bovine skin. In contrast, HHL cross-links were present (0.22 moles of cross-link per mole of collagen) in lattices of the same collagen contracted by fibroblasts. However, rat tail tendon does not contain HHL cross-links, and collagen lattices made of rat tail tendon collagen are capable of contraction. This suggests that telopeptide sites, and not mature HHL cross-links per se, are essential for fibroblasts to contract collagen lattices. Beta-aminopropionitrile fumarate (BAPN), a potent lathyrogen that perturbs collagen cross-linking by inhibition of lysyl oxidase, also inhibited the rate of lattice cell contraction in lattices composed of native collagen. However, the concentrations of BAPN that were necessary to inhibit the contraction of collagen lattices also inhibited fibroblast growth suggestive of cellular toxicity. In accordance with other studies, we found no inhibition of the rate of lattice contraction when fibronectin-depleted serum was used. Electron microscopy of contracted gels revealed typical collagen fibers with a characteristic axial periodicity. The data

  16. Sericin Enhances the Bioperformance of Collagen-Based Matrices Preseeded with Human-Adipose Derived Stem Cells (hADSCs)

    PubMed Central

    Dinescu, Sorina; Galateanu, Bianca; Albu, Madalina; Cimpean, Anisoara; Dinischiotu, Anca; Costache, Marieta

    2013-01-01

    Current clinical strategies for adipose tissue engineering (ATE), including autologous fat implants or the use of synthetic surrogates, not only are failing in the long term, but also can’t face the latest requirements regarding the aesthetic restoration of the resulted imperfections. In this context, modern strategies in current ATE applications are based on the implantation of 3D cell-scaffold bioconstructs, designed for prospective achievement of in situ functional de novo tissue. Thus, in this paper, we reported for the first time the evaluation of a spongious 60% collagen and 40% sericin scaffold preseeded with human adipose-derived stem cells (hADSCs) in terms of biocompatibility and adipogenic potential in vitro. We showed that the addition of the sticky protein sericin in the composition of a classical collagen sponge enhanced the adhesion and also the proliferation rate of the seeded cells, thus improving the biocompatibility of the novel scaffold. In addition, sericin stimulated PPARγ2 overexpression, triggering a subsequent upregulated expression profile of FAS, aP2 and perilipin adipogenic markers. These features, together with the already known sericin stimulatory potential on cellular collagen production, promote collagen-sericin biomatrix as a good candidate for soft tissue reconstruction and wound healing applications. PMID:23325052

  17. Self-Regulating Shock Absorber

    NASA Technical Reports Server (NTRS)

    Wesselski, Clarence J.

    1995-01-01

    Mechanical shock absorber keeps frictional damping force within tolerable limit. Its damping force does not increase with coefficient of friction between energy-absorbing components; rather, frictional damping force varies only slightly. Relatively insensitive to manufacturing variations and environmental conditions altering friction. Does not exhibit high breakaway friction and consequent sharp increase followed by sharp decrease in damping force at beginning of stroking. Damping force in absorber does not vary appreciably with speed of stroking. In addition, not vulnerable to leakage of hydraulic fluid.

  18. Genetic and orthopedic aspects of collagen disorders.

    PubMed

    Carter, Erin M; Raggio, Cathleen L

    2009-02-01

    'Collagens' are a family of structurally related proteins that play a wide variety of roles in the extracellular matrix. To date, there are at least 29 known types of collagen. Accordingly, abnormality in the various collagens produces a large category of diseases with heterogeneous symptoms. This review presents genetic and orthopedic aspects of type II, IX, and XI collagen disorders. Although a diverse group of conditions, mutation of collagens affecting the articular cartilage typically produces an epiphyseal skeletal dysplasia phenotype. Often, the ocular or auditory systems or both are also involved. Treatment of these collagenopathies is symptomatic and individualized. Study of tissue from animal models allows examination of mutation effects on the abnormal protein structure and function. The collagen superfamily comprises an important structural protein in mammalian connective tissue. Mutation of collagens produces a wide variety of genetic disorders, and those mutations affecting types II, IX, and XI collagens produce an overlapping spectrum of skeletal dysplasias. Findings range from lethal to mild, depending on the mutation of the collagen gene and its subsequent effect on the structure and/or metabolism of the resultant procollagen and/or collagen protein and its function in the body.

  19. Formation of Highly Aligned Collagen Nanofibers by Continuous Cyclic Stretch of a Collagen Hydrogel Sheet.

    PubMed

    Nam, Eunryel; Lee, Won Chul; Takeuchi, Shoji

    2016-07-01

    A collagen sheet with highly aligned collagen fibers is fabricated by continuous cyclic stretch. The rearrangement of the collagen fibers depends on the different process parameters of the cyclic stretch, including magnitude, frequency, and period of stretch. The collagen fibers are aligned perpendicularly to the direction of the stretch. Corneal stromal cells and smooth muscle cells cultivated on the highly aligned collagen sheet show alignment along the collagen fibers without the stretch during culture. Thus, the sheet can be a suitable scaffold for use in regenerative medicine. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Implementation of a protocol to reduce occurrence of retained sponges after vaginal delivery.

    PubMed

    Lutgendorf, Monica A; Schindler, Lynnett L; Hill, James B; Magann, Everett F; O'Boyle, John D

    2011-06-01

    Retained sponges (gossypiboma) following vaginal delivery are an uncommon occurrence. Although significant morbidity from such an event is unlikely, there are many reported adverse effects, including symptoms of malodorous discharge, loss of confidence in providers and the medical system, and legal claims. To report a protocol intended to reduce the occurrence of retained sponges following vaginal delivery. After identification of limitations with existing delivery room protocols, we developed a sponge count protocol to reduce occurrence of retained vaginal sponges. We report our experience at Naval Medical Center Portsmouth, a large tertiary care military treatment facility with our efforts to implement a sponge count protocol to reduce retained sponges following vaginal delivery. With appropriate pre-implementation training, protocols which incorporate post-delivery vaginal sweep and sponge counts are well accepted by the health care team and can be incorporated into the delivery room routine.

  1. A Novel Functional Role of Collagen Glycosylation

    PubMed Central

    Jürgensen, Henrik J.; Madsen, Daniel H.; Ingvarsen, Signe; Melander, Maria C.; Gårdsvoll, Henrik; Patthy, Laszlo; Engelholm, Lars H.; Behrendt, Niels

    2011-01-01

    Collagens make up the most abundant component of interstitial extracellular matrices and basement membranes. Collagen remodeling is a crucial process in many normal physiological events and in several pathological conditions. Some collagen subtypes contain specific carbohydrate side chains, the function of which is poorly known. The endocytic collagen receptor urokinase plasminogen activator receptor-associated protein (uPARAP)/Endo180 plays an important role in matrix remodeling through its ability to internalize collagen for lysosomal degradation. uPARAP/Endo180 is a member of the mannose receptor protein family. These proteins all include a fibronectin type II domain and a series of C-type lectin-like domains, of which only a minor part possess carbohydrate recognition activity. At least two of the family members, uPARAP/Endo180 and the mannose receptor, interact with collagens. The molecular basis for this interaction is known to involve the fibronectin type II domain but nothing is known about the function of the lectin domains in this respect. In this study, we have investigated a possible role of the single active lectin domain of uPARAP/Endo180 in the interaction with collagens. By expressing truncated recombinant uPARAP/Endo180 proteins and analyzing their interaction with collagens with high and low levels of glycosylation we demonstrated that this lectin domain interacts directly with glycosylated collagens. This interaction is functionally important because it was found to modulate the endocytic efficiency of the receptor toward highly glycosylated collagens such as basement membrane collagen IV. Surprisingly, this property was not shared by the mannose receptor, which internalized glycosylated collagens independently of its lectin function. This role of modulating its uptake efficiency by a specific receptor is a previously unrecognized function of collagen glycosylation. PMID:21768090

  2. Sponge non-metastatic Group I Nme gene/protein - structure and function is conserved from sponges to humans

    PubMed Central

    2011-01-01

    Background Nucleoside diphosphate kinases NDPK are evolutionarily conserved enzymes present in Bacteria, Archaea and Eukarya, with human Nme1 the most studied representative of the family and the first identified metastasis suppressor. Sponges (Porifera) are simple metazoans without tissues, closest to the common ancestor of all animals. They changed little during evolution and probably provide the best insight into the metazoan ancestor's genomic features. Recent studies show that sponges have a wide repertoire of genes many of which are involved in diseases in more complex metazoans. The original function of those genes and the way it has evolved in the animal lineage is largely unknown. Here we report new results on the metastasis suppressor gene/protein homolog from the marine sponge Suberites domuncula, NmeGp1Sd. The purpose of this study was to investigate the properties of the sponge Group I Nme gene and protein, and compare it to its human homolog in order to elucidate the evolution of the structure and function of Nme. Results We found that sponge genes coding for Group I Nme protein are intron-rich. Furthermore, we discovered that the sponge NmeGp1Sd protein has a similar level of kinase activity as its human homolog Nme1, does not cleave negatively supercoiled DNA and shows nonspecific DNA-binding activity. The sponge NmeGp1Sd forms a hexamer, like human Nme1, and all other eukaryotic Nme proteins. NmeGp1Sd interacts with human Nme1 in human cells and exhibits the same subcellular localization. Stable clones expressing sponge NmeGp1Sd inhibited the migratory potential of CAL 27 cells, as already reported for human Nme1, which suggests that Nme's function in migratory processes was engaged long before the composition of true tissues. Conclusions This study suggests that the ancestor of all animals possessed a NmeGp1 protein with properties and functions similar to evolutionarily recent versions of the protein, even before the appearance of true tissues

  3. Countercurrent flow absorber and desorber

    DOEpatents

    Wilkinson, William H.

    1984-01-01

    Countercurrent flow absorber and desorber devices are provided for use in absorption cycle refrigeration systems and thermal boosting systems. The devices have increased residence time and surface area resulting in improved heat and mass transfer characteristics. The apparatuses may be incorporated into open cycle thermal boosting systems in which steam serves both as the refrigerant vapor which is supplied to the absorber section and as the supply of heat to drive the desorber section of the system.

  4. Countercurrent flow absorber and desorber

    DOEpatents

    Wilkinson, W.H.

    1984-10-16

    Countercurrent flow absorber and desorber devices are provided for use in absorption cycle refrigeration systems and thermal boosting systems. The devices have increased residence time and surface area resulting in improved heat and mass transfer characteristics. The apparatuses may be incorporated into open cycle thermal boosting systems in which steam serves both as the refrigerant vapor which is supplied to the absorber section and as the supply of heat to drive the desorber section of the system. 9 figs.

  5. Tactile device utilizing a single magnetorheological sponge: experimental investigation

    NASA Astrophysics Data System (ADS)

    Kim, Soomin; Kim, Pyunghwa; Choi, Seung-Hyun; Oh, Jong-Seok; Choi, Seung-Bok

    2015-04-01

    In the field of medicine, several new areas have been currently introduced such as robot-assisted surgery. However, the major drawback of these systems is that there is no tactile communication between doctors and surgical sites. When the tactile system is brought up, telemedicine including telerobotic surgery can be enhanced much more than now. In this study, a new tactile device is designed using a single magnetorhological (MR) sponge cell to realize the sensation of human organs. MR fluids and an open celled polyurethane foam are used to propose the MR sponge cell. The viscous and elastic sensational behaviors of human organs are realized by the MR sponge cell. Before developing the tactile device, tactile sensation according to touch of human fingers are quantified in advance. The finger is then treated as a reduced beam bundle model (BBM) in which the fingertip is comprised of an elastic beam virtually. Under the reduced BBM, when people want to sense an object, the fingertip is investigated by pushing and sliding. Accordingly, while several magnitudes of magnetic fields are applied to the tactile device, normal and tangential reaction forces and bending moment are measured by 6-axis force/torque sensor instead of the fingertip. These measured data are used to compare with soft tissues. It is demonstrated that the proposed MR sponge cell can realize any part of the organ based on the obtained data.

  6. Manoalide-related Sesterterpene from the Marine Sponge Luffariella variabilis.

    PubMed

    Hamada, Toshiyuki; Harada, Daisuke; Hirata, Mitsunobu; Yamashita, Keisuke; Palaniveloo, Kishneth; Okamura, Hiroaki; Iwagawa, Tetsuo; Arima, Naomichi; Iriguchi, Toshiyuki; de Voogd, Nicole J; Vairappan, Charles S

    2015-06-01

    A new manoalide-related sesterterpene, (4E,6E)-dehydro-25-O-methylmanoalide (1), was isolated from the organic extracts of the Bornean marine sponge Luffariella variabilis, together with the known compound (4E,6E)-dehydromanoalide (2). The structure of compound 1 was elucidated by interpretation of its spectroscopic data.

  7. Gourds: Bitter, Bottle, Wax, Snake, Sponge and Ridge

    USDA-ARS?s Scientific Manuscript database

    Minor cucurbits include bitter gourd, bottle gourd, wax gourd, snake gourd, and sponge and ridge gourd, which are significant dietary sources of nutrients such as vitamin A and C, iron and calcium. These cucurbits are cultivated and marketed by smallholder farmers and remain important components of ...

  8. Keratin sponge/hydrogel II, active agent delivery

    USDA-ARS?s Scientific Manuscript database

    Keratin sponge/hydrogels from oxidation and reduction hydrolysis of fine and coarse wool fibers were formed to behave as cationic hydrogels to swell and release active agents in the specific region of the gastro-intestinal (GI) tract. Their porous, interpenetrating networks (IPN) were effective for...

  9. Animals of the Sea: Coelenterates, Protozoa, and Sponges.

    ERIC Educational Resources Information Center

    Awkerman, Gary L.

    These three units are designed for use with standard science curricula. These publications, relating to animals of the sea, are: Protozoa, Sponges, and Coelenterates. Included are teacher guides, student activities, and demonstrations designed to impart ocean science understanding to high school students. Objectives to be attained from the unit on…

  10. SITE TECHNOLOGY CAPSULE: DYNAPHORE, INC., FORAGER™ SPONGE TECHNOLOGY

    EPA Science Inventory

    The Forager™ Sponge is a volume reduction technology in which heavy metal contaminants from an aqueous medium are selectively concentrated into a smaller volume for facilitated disposal. The technology treats contaminated groundwater, surface waters, and process waters by absorbi...

  11. Dinoflagellates associated with freshwater sponges from the ancient lake baikal.

    PubMed

    Annenkova, Natalia V; Lavrov, Dennis V; Belikov, Sergey I

    2011-04-01

    Dinoflagellates are a diverse group of protists that are common in both marine and freshwater environments. While the biology of marine dinoflagellates has been the focus of several recent studies, their freshwater relatives remain little-investigated. In the present study we explore the diversity of dinoflagellates in Lake Baikal by identifying and analyzing dinoflagellate sequences for 18S rDNA and ITS-2 from total DNA extracted from three species of endemic Baikalian sponges (Baikalospongia intermedia,Baikalospongia rectaand Lubomirskia incrustans). Phylogenetic analyses of these sequences revealed extensive dinoflagellate diversity in Lake Baikal. We found two groups of sequences clustering within the order Suessiales, known for its symbiotic relationships with various invertebrates. Thus they may be regarded as potential symbionts of Baikalian sponges. In addition,Gyrodinium helveticum, representatives from the genus Gymnodinium, dinoflagellates close to the family Pfiesteriaceae, and a few dinoflagellates without definite affiliation were detected. No pronounced difference in the distribution of dinoflagellates among the studied sponges was found, except for the absence of the Piscinoodinium-like dinoflagellates inL. incrustans. To the best of our knowledge, this is the first study of the diversity of dinoflagellates in freshwater sponges, the first systematic investigation of dinoflagellate molecular diversity in Lake Baikal and the first finding of members of the order Suessiales as symbionts of freshwater invertebrates. Copyright © 2010 Elsevier GmbH. All rights reserved.

  12. Symbiotic Fungus of Marine Sponge Axinella sp. Producing Antibacterial Agent

    NASA Astrophysics Data System (ADS)

    Trianto, A.; Widyaningsih, S.; Radjasa, OK; Pribadi, R.

    2017-02-01

    The emerging of multidrug resistance pathogenic bacteria cause the treatment of the diseaseshave become ineffective. There for, invention of a new drug with novel mode of action is an essential for curing the disease caused by an MDR pathogen. Marine fungi is prolific source of bioactive compound that has not been well explored. This study aim to obtain the marine sponges-associated fungus that producing anti-MDR bacteria substaces. We collected the sponge from Riung water, NTT, Indonesia. The fungus was isolated with affixed method, followed with purification with streak method. The overlay and disk diffusion agar methods were applied for bioactivity test for the isolate and the extract, respectively. Molecular analysis was employed for identification of the isolate. The sponge was identified based on morphological and spicular analysis. The ovelay test showed that the isolate KN15-3 active against the MDR Staphylococcus aureus and Eschericia coli. The extract of the cultured KN15-3 was also inhibited the S. aureus and E. coli with inhibition zone 2.95 mm and 4.13 mm, respectively. Based on the molecular analysis, the fungus was identified as Aspergillus sydowii. While the sponge was identified as Axinella sp.

  13. Growth efficiency and carbon balance for the sponge Haliclona oculata.

    PubMed

    Koopmans, Marieke; Martens, Dirk; Wijffels, Rene H

    2010-06-01

    To obtain more knowledge about carbon requirements for growth by sponges, the growth rate, respiration rate, and clearance rate was measured in situ in Haliclona oculata. We found that only 34% of the particulate carbon pumped through the sponge was used for both respiration and growth. The net growth efficiency, being the ratio of carbon incorporated in biomass and the total carbon used by the sponge for respiration and growth, was found to be 0.099 +/- 0.013. Thus, about 10% of the total used carbon was fixed in biomass, and over 90% was used for generating energy for growth, maintenance, reproduction, and pumping. H. oculata had 2.5 micromol C available for every micromole O2 consumed. A value of 0.75 for respiratory quotient (RQ in micromole CO2 micromole O2(-1) ) was used for H. oculata, which is the average value reported in literature for different marine invertebrates. Thus, carbon was available in excess to meet the respiratory demand. Oxygen was found not to be the limiting factor for growth, since only 3.3% of the oxygen pumped through the sponge body was used. Our results indicate that both oxygen and carbon availability are not limiting. The low growth efficiency agrees with the low growth rates found for the species used in this study.

  14. Significance of starch properties and quantity on sponge cake volume

    USDA-ARS?s Scientific Manuscript database

    We evaluated the qualitative and quantitative effects of wheat starch on sponge cake (SC) baking quality. Twenty wheat flours, including soft white and club wheat of normal, partial waxy and waxy endosperm, and hard wheat, were tested for amylose content, pasting properties, and SC baking quality. S...

  15. Endosymbiotic calcifying bacteria across sponge species and oceans

    NASA Astrophysics Data System (ADS)

    Garate, Leire; Sureda, Jan; Agell, Gemma; Uriz, Maria J.

    2017-03-01

    From an evolutionary point of view, sponges are ideal targets to study marine symbioses as they are the most ancient living metazoans and harbour highly diverse microbial communities. A recently discovered association between the sponge Hemimycale columella and an intracellular bacterium that generates large amounts of calcite spherules has prompted speculation on the possible role of intracellular bacteria in the evolution of the skeleton in early animals. To gain insight into this purportedly ancestral symbiosis, we investigated the presence of symbiotic bacteria in Mediterranean and Caribbean sponges. We found four new calcibacteria OTUs belonging to the SAR116 in two orders (Poecilosclerida and Clionaida) and three families of Demospongiae, two additional OTUs in cnidarians and one more in seawater (at 98.5% similarity). Using a calcibacteria targeted probe and CARD-FISH, we also found calcibacteria in Spirophorida and Suberitida and proved that the calcifying bacteria accumulated at the sponge periphery, forming a skeletal cortex, analogous to that of siliceous microscleres in other demosponges. Bacteria-mediated skeletonization is spread in a range of phylogenetically distant species and thus the purported implication of bacteria in skeleton formation and evolution of early animals gains relevance.

  16. Effect of wheat flour characteristics on sponge cake quality.

    PubMed

    Moiraghi, Malena; de la Hera, Esther; Pérez, Gabriela T; Gómez, Manuel

    2013-02-01

    To select the flour parameters that relate strongly to cake-making performance, in this study the relationship between sponge cake quality, solvent retention capacity (SRC) profile and flour physicochemical characteristics was investigated using 38 soft wheat samples of different origins. Particle size average, protein, damaged starch, water-soluble pentosans, total pentosans, SRC and pasting properties were analysed. Sponge cake volume and crumb texture were measured to evaluate cake quality. Cluster analysis was applied to assess differences in flour quality parameters among wheat lines based on the SRC profile. Cluster 1 showed significantly higher sponge cake volume and crumb softness, finer particle size and lower SRC sucrose, SRC carbonate, SRC water, damaged starch and protein content. Particle size, damaged starch, protein, thickening capacity and SRC parameters correlated negatively with sponge cake volume, while total pentosans and pasting temperature showed the opposite effect. The negative correlations between cake volume and SRC parameters along with the cluster analysis results indicated that flours with smaller particle size, lower absorption capacity and higher pasting temperature had better cake-making performance. Some simple analyses, such as SRC, particle size distribution and pasting properties, may help to choose flours suitable for cake making. Copyright © 2012 Society of Chemical Industry.

  17. Collagen mimetic peptide engineered M13 bacteriophage for collagen targeting and imaging in cancer.

    PubMed

    Jin, Hyo-Eon; Farr, Rebecca; Lee, Seung-Wuk

    2014-11-01

    Collagens are over-expressed in various human cancers and subsequently degraded and denatured by proteolytic enzymes, thus making them a target for diagnostics and therapeutics. Genetically engineered bacteriophage (phage) is a promising candidate for the development of imaging or therapeutic materials for cancer collagen targeting due to its promising structural features. We genetically engineered M13 phages with two functional peptides, collagen mimetic peptide and streptavidin binding peptide, on their minor and major coat proteins, respectively. The resulting engineered phage functions as a therapeutic or imaging material to target degraded and denatured collagens in cancerous tissues. We demonstrated that the engineered phages are able to target and label abnormal collagens expressed on A549 human lung adenocarcinoma cells after the conjugation with streptavidin-linked fluorescent agents. Our engineered collagen binding phage could be a useful platform for abnormal collagen imaging and drug delivery in various collagen-related diseases. Published by Elsevier Ltd.

  18. Sponge bioerosion accelerated by ocean acidification across species and latitudes?

    NASA Astrophysics Data System (ADS)

    Wisshak, M.; Schönberg, C. H. L.; Form, A.; Freiwald, A.

    2014-06-01

    In many marine biogeographic realms, bioeroding sponges dominate the internal bioerosion of calcareous substrates such as mollusc beds and coral reef framework. They biochemically dissolve part of the carbonate and liberate so-called sponge chips, a process that is expected to be facilitated and accelerated in a more acidic environment inherent to the present global change. The bioerosion capacity of the demosponge Cliona celata Grant, 1826 in subfossil oyster shells was assessed via alkalinity anomaly technique based on 4 days of experimental exposure to three different levels of carbon dioxide partial pressure ( pCO2) at ambient temperature in the cold-temperate waters of Helgoland Island, North Sea. The rate of chemical bioerosion at present-day pCO2 was quantified with 0.08-0.1 kg m-2 year-1. Chemical bioerosion was positively correlated with increasing pCO2, with rates more than doubling at carbon dioxide levels predicted for the end of the twenty-first century, clearly confirming that C. celata bioerosion can be expected to be enhanced with progressing ocean acidification (OA). Together with previously published experimental evidence, the present results suggest that OA accelerates sponge bioerosion (1) across latitudes and biogeographic areas, (2) independent of sponge growth form, and (3) for species with or without photosymbionts alike. A general increase in sponge bioerosion with advancing OA can be expected to have a significant impact on global carbonate (re)cycling and may result in widespread negative effects, e.g. on the stability of wild and farmed shellfish populations, as well as calcareous framework builders in tropical and cold-water coral reef ecosystems.

  19. Giving the early fossil record of sponges a squeeze.

    PubMed

    Antcliffe, Jonathan B; Callow, Richard H T; Brasier, Martin D

    2014-11-01

    Twenty candidate fossils with claim to be the oldest representative of the Phylum Porifera have been re-analysed. Three criteria are used to assess each candidate: (i) the diagnostic criteria needed to categorize sponges in the fossil record; (ii) the presence, or absence, of such diagnostic features in the putative poriferan fossils; and (iii) the age constraints for the candidate fossils. All three criteria are critical to the correct interpretation of any fossil and its placement within an evolutionary context. Our analysis shows that no Precambrian fossil candidate yet satisfies all three of these criteria to be a reliable sponge fossil. The oldest widely accepted candidate, Mongolian silica hexacts from c. 545 million years ago (Ma), are here shown to be cruciform arsenopyrite crystals. The oldest reliable sponge remains are siliceous spicules from the basal Cambrian (Protohertzina anabarica Zone) Soltanieh Formation, Iran, which are described and analysed here in detail for the first time. Extensive archaeocyathan sponge reefs emerge and radiate as late as the middle of the Fortunian Stage of the Cambrian and demonstrate a gradual assembly of their skeletal structure through this time coincident with the evolution of other metazoan groups. Since the Porifera are basal in the Metazoa, their presence within the late Proterozoic has been widely anticipated. Molecular clock calibration for the earliest Porifera and Metazoa should now be based on the Iranian hexactinellid material dated to c. 535 Ma. The earliest convincing fossil sponge remains appeared at around the time of the Precambrian-Cambrian boundary, associated with the great radiation events of that interval. © 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical Society.

  20. [Superficial sponge anesthesia in cataract surgery (with scleral tunnel incision)].

    PubMed

    Pham, D T; Scherer, V; Wollensak, J

    1996-12-01

    The successful development of cataract operation and IOL implantation in the last decade has resulted in progressive shortening of the incision length as well as in developing safer and simpler anesthetic techniques. The purpose of the present study was to evaluate whether cataract surgery with scleral incision is possible using only topical sponge anesthesia with oxybuprocaine 0.4%. This method was compared with retrobulbar injection. 150 patients (3 groups each consisting 50 eyes) underwent phaco with scleral incision. 1st group: oxybuprocaine sponge anesthesia. 2nd group: oxybuprocaine sponge anesthesia combined with mild systemic analgesia (tramadol p.o.). 3rd group: retrobulbar injection (prilocaine/etidocaine mixture). All patients received medazolam premedication (Dormicum, 3/10 of 1 cc). Pain and discomfort during and after operation were investigated and statistically analyzed. Neither in group 1, 2 or 3 an additional subconjunctival injection was necessary. Pain or discomfort during operation was felt in 14 percent of the patients anesthetized with the oxybuprocaine sponge but only in 6 percent of the patients additionally premedicated with tramadol (2nd group). Also 6 percent of the patients after retrobulbar injection felt pain during operation. Postoperatively no significant differences between group 1 and 2 were obtained: 6 percent felt pain, 30 percent had a short term foreign body sensation. After retrobulbar injection (group 3) only 10 percent felt postoperative pain or discomfort. Topically applied oxybuprocaine provides sufficient anesthesia during cataract surgery with scleral incision. A combination with mild systemic analgesia (tramadol) helps to minimize pain and discomfort. Retrobulbur injection yielded only in the postoperative period significantly better analgesia. In the operating room full cooperation of the patient is required. Therefore we recommend not to use sponge anesthesia in cases when communication between surgeon and patient is

  1. Jellyfish collagen matrices conserve the chondrogenic phenotype in two- and three-dimensional collagen matrices.

    PubMed

    Sewing, Judith; Klinger, Matthias; Notbohm, Holger

    2017-03-01

    Cartilage is a tissue with a very low capability of self-repair and the search for suitable materials supporting the chondrogenic phenotype and thus avoiding fibrotic dedifferentiation for matrix-associated chondrocyte transplantation (MACI) is ongoing. Jellyfish collagen was thought to be a suitable material mainly because of its good availability and easy handling. Collagen was extracted from jellyfish Rhopilema esculentum and the spreading of porcine chondrocytes on two (2D) and three dimensional (3D) collagen matrices examined in comparison with vertebrate collagens, placenta collagen and a commercially available matrix from porcine collagen type I (Optimaix®). In 2D, most chondrocytes kept their round shape on jellyfish collagen and vertebrate collagen type II compared with vertebrate collagen type I. This was also confirmed in 3D experiments, where chondrocytes preserved their phenotype on jellyfish collagen, as indicated by high collagen II/(II + I) ratios (≥54 % and ~92 % collagen type II in mRNA and protein, respectively) and no proliferation during 28 days of cultivation. These observations were discussed with a view to potential structural differences of jellyfish collagen, which might influence the integrin-mediated adhesion mechanisms of vertebrate cells on jellyfish collagen. This probably results from a lack of integrin-binding sites and the existence of an alternative binding mechanism such that cells kept their round shape on jellyfish collagen, preventing chondrocytes from dedifferentiation. Thus, collagen from R. esculentum is a very suitable and promising material for cartilage tissue engineering. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  2. Effects of sludge concentrations and different sponge configurations on the performance of a sponge-submerged membrane bioreactor.

    PubMed

    Nguyen, Tien Thanh; Ngo, Huu Hao; Guo, Wenshan; Li, Jianxin; Listowski, Andrzej

    2012-07-01

    The performance of a novel sponge-submerged membrane bioreactor (SSMBR) was evaluated to treat primary treated sewage effluent at three different activated sludge concentrations. Polyurethane sponge cubes with size of 1 × 1 × 1 cm were used as attached growth media in the bioreactor. The results indicated the successful removal of organic carbon and phosphorous with the efficiency higher than 98% at all conditions. Acclimatised sponge MBR showed about 5% better ammonia nitrogen removal at 5 and 10 g/L sludge concentration as compared to the new sponge system. The respiration test revealed that the specific oxygen uptake rate was around 1.0-3.5 mgO(2)/gVSS.h and likely more stable at 10 g/L sludge concentration. The sludge volume index of less than 100 mL/g during the operation indicated the good settling property of the sludge. The low mixed liquor suspended solid increase indicated that SSMBR could control the sludge production. This SSMBR was also successful in reducing membrane fouling with significant lower transmembrane pressure (e.g. only 0.5 kPa/day) compared to the conventional MBR system. Further study will be conducted to optimise other operating conditions.

  3. Fluorescence, aggregation properties and FT-IR microspectroscopy of elastin and collagen fibers.

    PubMed

    Vidal, Benedicto de Campos

    2014-10-01

    Histological and histochemical observations support the hypothesis that collagen fibers can link to elastic fibers. However, the resulting organization of elastin and collagen type complexes and differences between these materials in terms of macromolecular orientation and frequencies of their chemical vibrational groups have not yet been solved. This study aimed to investigate the macromolecular organization of pure elastin, collagen type I and elastin-collagen complexes using polarized light DIC-microscopy. Additionally, differences and similarities between pure elastin and collagen bundles (CB) were investigated by Fourier transform-infrared (FT-IR) microspectroscopy. Although elastin exhibited a faint birefringence, the elastin-collagen complex aggregates formed in solution exhibited a deep birefringence and formation of an ordered-supramolecular complex typical of collagen chiral structure. The FT-IR study revealed elastin and CB peptide NH groups involved in different types of H-bonding. More energy is absorbed in the vibrational transitions corresponding to CH, CH2 and CH3 groups (probably associated with the hydrophobicity demonstrated by 8-anilino-1-naphtalene sulfonic acid sodium salt [ANS] fluorescence), and to νCN, δNH and ωCH2 groups of elastin compared to CB. It is assumed that the α-helix contribution to the pure elastin amide I profile is 46.8%, whereas that of the B-sheet is 20% and that unordered structures contribute to the remaining percentage. An FT-IR profile library reveals that the elastin signature within the 1360-1189cm(-1) spectral range resembles that of Conex-Toray aramid fibers. Copyright © 2014 Elsevier GmbH. All rights reserved.

  4. Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems

    PubMed Central

    Rix, Laura; de Goeij, Jasper M.; Mueller, Christina E.; Struck, Ulrich; Middelburg, Jack J.; van Duyl, Fleur C.; Al-Horani, Fuad A.; Wild, Christian; Naumann, Malik S.; van Oevelen, Dick

    2016-01-01

    Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and nutrients in DOM to higher trophic levels on Caribbean reefs via the so-called sponge loop. Coral mucus may be a major DOM source for the sponge loop, but mucus uptake by sponges has not been demonstrated. Here we used laboratory stable isotope tracer experiments to show the transfer of coral mucus into the bulk tissue and phospholipid fatty acids of the warm-water sponge Mycale fistulifera and cold-water sponge Hymedesmia coriacea, demonstrating a direct trophic link between corals and reef sponges. Furthermore, 21–40% of the mucus carbon and 32–39% of the nitrogen assimilated by the sponges was subsequently released as detritus, confirming a sponge loop on Red Sea warm-water and north Atlantic cold-water coral reefs. The presence of a sponge loop in two vastly different reef environments suggests it is a ubiquitous feature of reef ecosystems contributing to the high biogeochemical cycling that may enable coral reefs to thrive in nutrient-limited (warm-water) and energy-limited (cold-water) environments. PMID:26740019

  5. Assessment of the characteristics and biocompatibility of gelatin sponge scaffolds prepared by various crosslinking methods.

    PubMed

    Yang, Gang; Xiao, Zhenghua; Long, Haiyan; Ma, Kunlong; Zhang, Junpeng; Ren, Xiaomei; Zhang, Jiang

    2018-01-25

    This comparative study aims to identify a biocompatible and effective crosslinker for preparing gelatin sponges. Glutaraldehyde (GTA), genipin (GP), 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide (EDC), and microbial transglutaminase (mTG) were used as crosslinking agents. The physical properties of the prepared samples were characterized, and material degradation was studied in vitro with various proteases and in vivo through subcutaneous implantation of the sponges in rats. Adipose-derived stromal stem cells (ADSCs) were cultured and inoculated onto the scaffolds to compare the cellular biocompatibility of the sponges. Cellular seeding efficiency and digestion time of the sponges were also evaluated. Cellular viability and proliferation in scaffolds were analyzed by fluorescence staining and MTT assay. All the samples exhibited high porosity, good swelling ratio, and hydrolysis properties; however, material strength, hydrolysis, and enzymolytic properties varied among the samples. GTA-sponge and GP-sponge possessed high compressive moduli, and EDC-sponge exhibited fast degradation performance. GTA and GP sponge implants exerted strong in vivo rejections, and the former showed poor cell growth. mTG-sponge exhibited the optimal comprehensive performance, with good porosity, compressive modulus, anti-degradation ability, and good biocompatibility. Hence, mTG-sponge can be used as a scaffold material for tissue engineering applications.

  6. Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems.

    PubMed

    Rix, Laura; de Goeij, Jasper M; Mueller, Christina E; Struck, Ulrich; Middelburg, Jack J; van Duyl, Fleur C; Al-Horani, Fuad A; Wild, Christian; Naumann, Malik S; van Oevelen, Dick

    2016-01-07

    Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and nutrients in DOM to higher trophic levels on Caribbean reefs via the so-called sponge loop. Coral mucus may be a major DOM source for the sponge loop, but mucus uptake by sponges has not been demonstrated. Here we used laboratory stable isotope tracer experiments to show the transfer of coral mucus into the bulk tissue and phospholipid fatty acids of the warm-water sponge Mycale fistulifera and cold-water sponge Hymedesmia coriacea, demonstrating a direct trophic link between corals and reef sponges. Furthermore, 21-40% of the mucus carbon and 32-39% of the nitrogen assimilated by the sponges was subsequently released as detritus, confirming a sponge loop on Red Sea warm-water and north Atlantic cold-water coral reefs. The presence of a sponge loop in two vastly different reef environments suggests it is a ubiquitous feature of reef ecosystems contributing to the high biogeochemical cycling that may enable coral reefs to thrive in nutrient-limited (warm-water) and energy-limited (cold-water) environments.

  7. Culturable heterotrophic bacteria from the marine sponge Dendrilla nigra: isolation and phylogenetic diversity of actinobacteria

    NASA Astrophysics Data System (ADS)

    Selvin, Joseph; Gandhimathi, R.; Kiran, G. Seghal; Priya, S. Shanmugha; Ravji, T. Rajeetha; Hema, T. A.

    2009-09-01

    Culturable heterotrophic bacterial composition of marine sponge Dendrilla nigra was analysed using different enrichments. Five media compositions including without enrichment (control), enriched with sponge extract, with growth regulator (antibiotics), with autoinducers, and complete enrichment containing sponge extract, antibiotics, and autoinducers were developed. DNA hybridization assay was performed to explore host specific bacteria and ecotypes of culturable sponge-associated bacteria. Enrichment with selective inducers (AHLs and sponge extract) and regulators (antibiotics) considerably enhanced the cultivation potential of sponge-associated bacteria. It was found that Marinobacter (MSI032), Micromonospora (MSI033), Streptomyces (MSI051), and Pseudomonas (MSI057) were sponge-associated obligate symbionts. The present findings envisaged that “ Micromonospora-Saccharomonospora-Streptomyces” group was the major culturable actinobacteria in the marine sponge D. nigra. The DNA hybridization assay was a reliable method for the analysis of culturable bacterial community in marine sponges. Based on the culturable community structure, the sponge-associated bacteria can be grouped (ecotypes) as general symbionts, specific symbionts, habitat flora, and antagonists.

  8. Sponge epibionts on ecosystem-engineering ascidians: The case of Microcosmus sabatieri

    NASA Astrophysics Data System (ADS)

    Voultsiadou, Eleni; Kyrodimou, Marianthi; Antoniadou, Chryssanthi; Vafidis, Dimitris

    2010-03-01

    The study of epibionts on habitat engineering ascidians is of increasing interest because changes in the population structure of the latter may affect associated communities, especially in the case of commercially exploited species. The solitary ascidian Microcosmus sabatieri lives on rocky cliffs in the Eastern Mediterranean and is harvested in certain Aegean areas. Its hard, wrinkled tunic is usually fouled by various epibionts both sessile and motile. Sponges are an important component of this complex and their biomass may be higher than that of the ascidian itself, strongly affecting diversity and abundance of the motile epifauna. The aim of this study was to examine in detail the structure of the epibiotic sponge assemblage on ascidians collected from their main fishing grounds in the South Aegean Sea. A rich (41 species) and taxonomically diverse sponge assemblage was found, while only eight species contributed 80% of the total sponge cover. Most of the epibiotic sponges commonly grow on the surrounding sublittoral cliffs. The encrusting sponge growth form prevailed in cover of the ascidian tunic, while two massive species dominated in terms of frequency of appearance and abundance. Ascidian dimensions, weight and volume were significantly correlated with sponge diversity, abundance and cover area, thus structuring the epibiotic sponge assemblage. Spatial patterns in sponge cover were not clear, but a general declining NW to SE trend in sponge richness, abundance and cover appeared in accordance with previous records. Sponge distribution on the ascidian tunic presented a clear pattern related with characteristic features of the ascidian: the posterior zone supported the richest and most expansive sponge fauna. The ecosystem-engineering process performed by the ascidian is enhanced by the diverse epibiotic sponge assemblage, thus further increasing habitat complexity in this space-limited, temperate, sublittoral, rocky environment.

  9. Early-term and mid-term histologic events during single-level posterolateral intertransverse process fusion with rhBMP-2/collagen carrier and a ceramic bulking agent in a nonhuman primate model: implications for bone graft preparation.

    PubMed

    Khan, Safdar N; Toth, Jeffrey M; Gupta, Kavita; Glassman, Steven D; Gupta, Munish C

    2014-06-01

    We used a nonhuman primate lumbar intertransverse process arthrodesis model to evaluate biological cascade of bone formation using different carrier preparation methods with a single dose of recombinant human bone morphogenetic protein-2 (rhBMP-2) at early time points. To examine early-term/mid-term descriptive histologic and computerized tomographic events in single-level uninstrumented posterolateral nonhuman primate spinal fusions using rhBMP-2/absorbable collagen sponge (ACS) combined with ceramic bulking agents in 3 different configurations. rhBMP-2 on an ACS carrier alone leads to consistent posterolateral lumbar spine fusions in lower-order animals; however, these results have been difficult to replicate in nonhuman primates. Twelve skeletally mature, rhesus macaque monkeys underwent single-level posterolateral arthrodesis at L4-L5. A hydroxyapatite/β-tricalcium phosphate ceramic bulking agent in 3 formulations was used in the treatment groups (n=3). When used, rhBMP-2/ACS at 1.5 mg/cm (3.0 mg rhBMP-2) was combined with 2.5 cm of ceramic bulking agent per side. Animals were euthanized at 4 and 12 weeks postoperative. Computerized tomography scans were performed immediately postoperatively and every 4 weeks until they were euthanized. Sagittal histologic sections were evaluated for bone histogenesis and location, cellular infiltration of the graft/substitute, and bone remodeling activity. Significant histologic differences in the developing fusion appeared between the 3 rhBMP-2/ACS treatment groups at 4 and 12 weeks. At 4 weeks, bone formation appeared to originate at the transverse process and the intertransverse membrane. Cellular infiltration was greatest in granular ceramic groups compared with matrix ceramic group. Minimal to no residual ACS was identified at the early time point. At 12 weeks, marked ceramic remodeling was observed with continued bone formation noted in all carrier groups. At the early time period, histology showed that bone formation

  10. Bone resorption analysis of platelet-derived growth factor type BB application on collagen for bone grafts secured by titanium mesh over a pig jaw defect model

    PubMed Central

    Herford, Alan Scott; Cicciù, Marco

    2012-01-01

    Purpose: The aim of this investigation was to evaluate whether the addition of the platelet derived growth factor type BB (PDGF-BB) to a collagen matrix applied on a titanium mesh would favor healing and resorption onto the grafted bone. A histologic and radiographic study of two different groups (test and control) was performed. Designs: A surgical procedure was performed on 8 pigs to obtain 16 bilateral mandibular alveolar defects. All the defects were then reconstructed with a mixture of autogenous bovine bone using titanium mesh positioning. Two groups, with a total of 16 defects were created: The first to study collagen sponge and PDGF-BB and the second to control collagen only. The collagen matrix was positioned directly over the mesh and soft tissue was closed without tensions onto both groups without attempting to obtain primary closure. Possible exposure of the titanium mesh as well as the height and volume of the new bone was recorded. Results: New bone formation averaged about 6.68 mm in the test group studied; the control group had less regenerated bone at 4.62 mm. Conclusion: PDGF-BB addition to the collagen matrix induced a strong increase in hard and soft tissue healing and favored bone formation, reducing bone resorption even if the mesh was exposed. PMID:23833493

  11. Carbon Absorber Retrofit Equipment (CARE)

    SciTech Connect

    Klein, Eric

    During Project DE-FE0007528, CARE (Carbon Absorber Retrofit Equipment), Neumann Systems Group (NSG) designed, installed and tested a 0.5MW NeuStream® carbon dioxide (CO 2) capture system using the patented NeuStream® absorber equipment and concentrated (6 molal) piperazine (PZ) as the solvent at Colorado Springs Utilities’ (CSU’s) Martin Drake pulverized coal (PC) power plant. The 36 month project included design, build and test phases. The 0.5MW NeuStream® CO 2 capture system was successfully tested on flue gas from both coal and natural gas combustion sources and was shown to meet project objectives. Ninety percent CO 2 removal was achieved with greater thanmore » 95% CO 2product purity. The absorbers tested support a 90% reduction in absorber volume compared to packed towers and with an absorber parasitic power of less than 1% when configured for operation with a 550MW coal plant. The preliminary techno-economic analysis (TEA) performed by the Energy and Environmental Research Center (EERC) predicted an over-the-fence cost of $25.73/tonne of CO 2 captured from a sub-critical PC plant.« less

  12. Mushroom plasmonic metamaterial infrared absorbers

    SciTech Connect

    Ogawa, Shinpei, E-mail: Ogawa.Shimpei@eb.MitsubishiElectric.co.jp; Fujisawa, Daisuke; Hata, Hisatoshi

    2015-01-26

    There has been a considerable amount of interest in the development of various types of electromagnetic wave absorbers for use in different wavelength ranges. In particular, infrared (IR) absorbers with wavelength selectivity can be applied to advanced uncooled IR sensors, which would be capable of identifying objects through their radiation spectrum. In the present study, mushroom plasmonic metamaterial absorbers (MPMAs) for the IR wavelength region were designed and fabricated. The MPMAs consist of a periodic array of thin metal micropatches connected to a thin metal plate with narrow silicon (Si) posts. A Si post height of 200 nm was achieved bymore » isotropic XeF{sub 2} etching of a thin Si layer sandwiched between metal plates. This fabrication procedure is relatively simple and is consistent with complementary metal oxide semiconductor technology. The absorption spectra of the fabricated MPMAs were experimentally measured. In addition, theoretical calculations of their absorption properties were conducted using rigorous coupled wave analysis. Both the calculated and measured absorbance results demonstrated that these MPMAs can realize strong selective absorption at wavelengths beyond the period of the array by varying the micropatch width. Absorbance values greater than 90% were achieved. Dual- or single-mode absorption can also be selected by varying the width of the Si posts. Pixel structures using such MPMAs could be used as high responsivity, high resolution and fast uncooled IR sensors.« less

  13. Additive manufacturing of RF absorbers

    NASA Astrophysics Data System (ADS)

    Mills, Matthew S.

    The ability of additive manufacturing techniques to fabricate integrated electromagnetic absorbers tuned for specific radio frequency bands within structural composites allows for unique combinations of mechanical and electromagnetic properties. These composites and films can be used for RF shielding of sensitive electromagnetic components through in-plane and out-of-plane RF absorption. Structural composites are a common building block of many commercial platforms. These platforms may be placed in situations in which there is a need for embedded RF absorbing properties along with structural properties. Instead of adding radar absorbing treatments to the external surface of existing structures, which adds increased size, weight and cost; it could prove to be advantageous to integrate the microwave absorbing properties directly into the composite during the fabrication process. In this thesis, a method based on additive manufacturing techniques of composites structures with prescribed electromagnetic loss, within the frequency range 1 to 26GHz, is presented. This method utilizes screen printing and nScrypt micro dispensing to pattern a carbon based ink onto low loss substrates. The materials chosen for this study will be presented, and the fabrication technique that these materials went through to create RF absorbing structures will be described. The calibration methods used, the modeling of the RF structures, and the applications in which this technology can be utilized will also be presented.

  14. Nanolayered Features of Collagen-like Peptides

    NASA Technical Reports Server (NTRS)

    Valluzzi, Regina; Bini, Elisabetta; Haas, Terry; Cebe, Peggy; Kaplan, David L.

    2003-01-01

    We have been investigating collagen-like model oligopeptides as molecular bases for complex ordered biomimetic materials. The collagen-like molecules incorporate aspects of native collagen sequence and secondary structure. Designed modifications to native primary and secondary structure have been incorporated to control the nanostructure and microstructure of the collagen-like materials produced. We find that the collagen-like molecules form a number of lyotropic rod liquid crystalline phases, which because of their strong temperature dependence in the liquid state can also be viewed as solvent intercalated thermotropic liquid crystals. The liquid crystalline phases formed by the molecules can be captured in the solid state by drying off solvent, resulting in solid nanopatterned (chemically and physically) thermally stable (to greater than 100 C) materials. Designed sequences which stabilize smectic phases have allowed a variety of nanoscale multilayered biopolymeric materials to be developed. Preliminary investigations suggest that chemical patterns running perpendicular to the smectic layer plane can be functionalized and used to localize a variety of organic, inorganic, and organometallic moieties in very simple multilayered nanocomposites. The phase behavior of collagen-like oligopeptide materials is described, emphasizing the correlation between mesophase, molecular orientation, and chemical patterning at the microscale and nanoscale. In many cases, the textures observed for smectic and hexatic phase collagens are remarkably similar to the complex (and not fully understood) helicoids observed in biological collagen-based tissues. Comparisons between biological morphologies and collagen model liquid crystalline (and solidified materials) textures may help us understand the molecular features which impart order and function to the extracellular matrix and to collagen-based mineralized tissues. Initial studies have utilized synthetic collagen-like peptides while

  15. Modern collagen wound dressings: function and purpose.

    PubMed

    Fleck, Cynthia Ann; Simman, Richard

    2010-09-01

    Collagen, which is produced by fibroblasts, is the most abundant protein in the human body. A natural structural protein, collagen is involved in all 3 phases of the wound-healing cascade. It stimulates cellular migration and contributes to new tissue development. Because of their chemotactic properties on wound fibroblasts, collagen dressings encourage the deposition and organization of newly formed collagen, creating an environment that fosters healing. Collagen-based biomaterials stimulate and recruit specific cells, such as macrophages and fibroblasts, along the healing cascade to enhance and influence wound healing. These biomaterials can provide moisture or absorption, depending on the delivery system. Collagen dressings are easy to apply and remove and are conformable. Collagen dressings are usually formulated with bovine, avian, or porcine collagen. Oxidized regenerated cellulose, a plant-based material, has been combined with collagen to produce a dressing capable of binding to and protecting growth factors by binding and inactivating matrix metalloproteinases in the wound environment. The increased understanding of the biochemical processes involved in chronic wound healing allows the design of wound care products aimed at correcting imbalances in the wound microenvironment. Traditional advanced wound care products tend to address the wound's macroenvironment, including moist wound environment control, fluid management, and controlled transpiration of wound fluids. The newer class of biomaterials and wound-healing agents, such as collagen and growth factors, targets specific defects in the chronic wound environment. In vitro laboratory data point to the possibility that these agents benefit the wound healing process at a biochemical level. Considerable evidence has indicated that collagen-based dressings may be capable of stimulating healing by manipulating wound biochemistry.

  16. Protection of biomass from snail overgrazing in a trickling filter using sponge media as a biomass carrier: down-flow hanging sponge system.

    PubMed

    Onodera, Takashi; Syutsubo, Kazuaki; Yoochatchaval, Wilasinee; Sumino, Haruhiko; Mizuochi, Motoyuki; Harada, Hideki

    2015-01-01

    This study investigated down-flow hanging sponge (DHS) technology as a promising trickling filter (TF) using sponge media as a biomass carrier with an emphasis on protection of the biomass against macrofauna overgrazing. A pilot-scale DHS reactor fed with low-strength municipal sewage was operated under ambient temperature conditions for 1 year at a sewage treatment plant in Bangkok, Thailand. The results showed that snails (macrofauna) were present on the surface of the sponge media, but could not enter into it, because the sponge media with smaller pores physically protected the biomass from the snails. As a result, the sponge media maintained a dense biomass, with an average value of 22.3 gVSS/L sponge (58.1 gTSS/L sponge) on day 370. The snails could graze biomass on the surface of the sponge media. The DHS reactor process performance was also successful. The DHS reactor requires neither chemical treatments nor specific operations such as flooding for snail control. Overall, the results of this study indicate that the DHS reactor is able to protect biomass from snail overgrazing.

  17. Metabolic profiles of prokaryotic and eukaryotic communities in deep-sea sponge Lamellomorpha sp. indicated by metagenomics

    NASA Astrophysics Data System (ADS)

    Li, Zhi-Yong; Wang, Yue-Zhu; He, Li-Ming; Zheng, Hua-Jun

    2014-01-01

    The whole metabolism of a sponge holobiont and the respective contributions of prokaryotic and eukaryotic symbionts and their associations with the sponge host remain largely unclear. Meanwhile, compared with shallow water sponges, deep-sea sponges are rarely understood. Here we report the metagenomic exploration of deep-sea sponge Lamellomorpha sp. at the whole community level. Metagenomic data showed phylogenetically diverse prokaryotes and eukaryotes in Lamellomorpha sp.. MEGAN and gene enrichment analyses indicated different metabolic potentials of prokaryotic symbionts from eukaryotic symbionts, especially in nitrogen and carbon metabolisms, and their molecular interactions with the sponge host. These results supported the hypothesis that prokaryotic and eukaryotic symbionts have different ecological roles and relationships with sponge host. Moreover, vigorous denitrification, and CO2 fixation by chemoautotrophic prokaryotes were suggested for this deep-sea sponge. The study provided novel insights into the respective potentials of prokaryotic and eukaryotic symbionts and their associations with deep-sea sponge Lamellomorpha sp..

  18. Metabolic profiles of prokaryotic and eukaryotic communities in deep-sea sponge Neamphius huxleyi indicated by metagenomics

    PubMed Central

    Li, Zhi-Yong; Wang, Yue-Zhu; He, Li-Ming; Zheng, Hua-Jun

    2014-01-01

    The whole metabolism of a sponge holobiont and the respective contributions of prokaryotic and eukaryotic symbionts and their associations with the sponge host remain largely unclear. Meanwhile, compared with shallow water sponges, deep-sea sponges are rarely understood. Here we report the metagenomic exploration of deep-sea sponge Neamphius huxleyi at the whole community level. Metagenomic data showed phylogenetically diverse prokaryotes and eukaryotes in Neamphius huxleyi. MEGAN and gene enrichment analyses indicated different metabolic potentials of prokaryotic symbionts from eukaryotic symbionts, especially in nitrogen and carbon metabolisms, and their molecular interactions with the sponge host. These results supported the hypothesis that prokaryotic and eukaryotic symbionts have different ecological roles and relationships with sponge host. Moreover, vigorous denitrification, and CO2 fixation by chemoautotrophic prokaryotes were suggested for this deep-sea sponge. The study provided novel insights into the respective potentials of prokaryotic and eukaryotic symbionts and their associations with deep-sea sponge Neamphius huxleyi. PMID:24463735

  19. Metabolic profiles of prokaryotic and eukaryotic communities in deep-sea sponge Neamphius huxleyi [corrected]. indicated by metagenomics.

    PubMed

    Li, Zhi-Yong; Wang, Yue-Zhu; He, Li-Ming; Zheng, Hua-Jun

    2014-01-27

    The whole metabolism of a sponge holobiont and the respective contributions of prokaryotic and eukaryotic symbionts and their associations with the sponge host remain largely unclear. Meanwhile, compared with shallow water sponges, deep-sea sponges are rarely understood. Here we report the metagenomic exploration of deep-sea sponge Neamphius huxleyi [corrected] . at the whole community level. Metagenomic data showed phylogenetically diverse prokaryotes and eukaryotes in Neamphius huxleyi [corrected]. MEGAN and gene enrichment analyses indicated different metabolic potentials of prokaryotic symbionts from eukaryotic symbionts, especially in nitrogen and carbon metabolisms, and their molecular interactions with the sponge host. These results supported the hypothesis that prokaryotic and eukaryotic symbionts have different ecological roles and relationships with sponge host. Moreover, vigorous denitrification, and CO2 fixation by chemoautotrophic prokaryotes were suggested for this deep-sea sponge. The study provided novel insights into the respective potentials of prokaryotic and eukaryotic symbionts and their associations with deep-sea sponge Neamphius huxleyi [corrected].

  20. Metagenomic Analysis of Genes Encoding Nutrient Cycling Pathways in the Microbiota of Deep-Sea and Shallow-Water Sponges.

    PubMed

    Li, Zhiyong; Wang, Yuezhu; Li, Jinlong; Liu, Fang; He, Liming; He, Ying; Wang, Shenyue

    2016-12-01

    Sponges host complex symbiotic communities, but to date, the whole picture of the metabolic potential of sponge microbiota remains unclear, particularly the difference between the shallow-water and deep-sea sponge holobionts. In this study, two completely different sponges, shallow-water sponge Theonella swinhoei from the South China Sea and deep-sea sponge Neamphius huxleyi from the Indian Ocean, were selected to compare their whole symbiotic communities and metabolic potential, particularly in element transformation. Phylogenetically diverse bacteria, archaea, fungi, and algae were detected in both shallow-water sponge T. swinhoei and deep-sea sponge N. huxleyi, and different microbial community structures were indicated between these two sponges. Metagenome-based gene abundance analysis indicated that, though the two sponge microbiota have similar core functions, they showed different potential strategies in detailed metabolic processes, e.g., in the transformation and utilization of carbon, nitrogen, phosphorus, and sulfur by corresponding microbial symbionts. This study provides insight into the putative metabolic potentials of the microbiota associated with the shallow-water and deep-sea sponges at the whole community level, extending our knowledge of the sponge microbiota's functions, the association of sponge- microbes, as well as the adaption of sponge microbiota to the marine environment.

  1. Relationships between Host Phylogeny, Host Type and Bacterial Community Diversity in Cold-Water Coral Reef Sponges

    PubMed Central

    Schöttner, Sandra; Hoffmann, Friederike; Cárdenas, Paco; Rapp, Hans Tore; Boetius, Antje; Ramette, Alban

    2013-01-01

    Cold-water coral reefs are known to locally enhance the diversity of deep-sea fauna as well as of microbes. Sponges are among the most diverse faunal groups in these ecosystems, and many of them host large abundances of microbes in their tissues. In this study, twelve sponge species from three cold-water coral reefs off Norway were investigated for the relationship between sponge phylogenetic classification (species and family level), as well as sponge type (high versus low microbial abundance), and the diversity of sponge-associated bacterial communities, taking also geographic location and water depth into account. Community analysis by Automated Ribosomal Intergenic Spacer Analysis (ARISA) showed that as many as 345 (79%) of the 437 different bacterial operational taxonomic units (OTUs) detected in the dataset were shared between sponges and sediments, while only 70 (16%) appeared purely sponge-associated. Furthermore, changes in bacterial community structure were significantly related to sponge species (63% of explained community variation), sponge family (52%) or sponge type (30%), whereas mesoscale geographic distances and water depth showed comparatively small effects (<5% each). In addition, a highly significant, positive relationship between bacterial community dissimilarity and sponge phylogenetic distance was observed within the ancient family of the Geodiidae. Overall, the high diversity of sponges in cold-water coral reefs, combined with the observed sponge-related variation in bacterial community structure, support the idea that sponges represent heterogeneous, yet structured microbial habitats that contribute significantly to enhancing bacterial diversity in deep-sea ecosystems. PMID:23393586

  2. Better Absorbents for Ammonia Separation

    SciTech Connect

    Malmali, Mahdi; Le, Giang; Hendrickson, Jennifer

    Making ammonia from renewable wind energy at a competitive price may be possible if the conventional ammonia condenser is replaced with an ammonia absorber. Such a process change requires an ammonia selective absorbent. Supported metal halide sorbents for this separation display outstanding dynamic capacity close to their equilibrium thermodynamic limits. Alkaline earth chlorides and bromides supported on silica and zeolite Y are the most promising. MgCl 2 and CaBr 2 at 40% loading on silica show capacities of 60-70 mg NH3/gsorbent at 150 °C and 4 bar. Overall, cations with smaller atomic numbers show more affinity to ammonia; bromides holdmore » ammonia more strongly than chlorides. Different solvents and metal halide mixtures do not show significant changes in the absorption capacity. Finally, these absorbents can be incorporated into ammonia reaction-absorption syntheses to achieve faster production rates.« less

  3. Better Absorbents for Ammonia Separation

    DOE PAGES

    Malmali, Mahdi; Le, Giang; Hendrickson, Jennifer; ...

    2018-03-30

    Making ammonia from renewable wind energy at a competitive price may be possible if the conventional ammonia condenser is replaced with an ammonia absorber. Such a process change requires an ammonia selective absorbent. Supported metal halide sorbents for this separation display outstanding dynamic capacity close to their equilibrium thermodynamic limits. Alkaline earth chlorides and bromides supported on silica and zeolite Y are the most promising. MgCl 2 and CaBr 2 at 40% loading on silica show capacities of 60-70 mg NH3/gsorbent at 150 °C and 4 bar. Overall, cations with smaller atomic numbers show more affinity to ammonia; bromides holdmore » ammonia more strongly than chlorides. Different solvents and metal halide mixtures do not show significant changes in the absorption capacity. Finally, these absorbents can be incorporated into ammonia reaction-absorption syntheses to achieve faster production rates.« less

  4. Low temperature selective absorber research

    NASA Astrophysics Data System (ADS)

    Herzenberg, S. A.; Silberglitt, R.

    1982-04-01

    Research carried out since 1979 on selective absorbers is surveyed, with particular attention given to the low-temperature coatings seen as promising for flat plate and evacuated tube applications. The most thoroughly investigated absorber is black chrome, which is highly selective and is the most durable low-temperature absorber. It is believed that other materials, because of their low cost and lower content of strategic materials, may eventually supplant black chrome. Among these candidates are chemically converted black nickel; anodically oxidized nickel, zinc, and copper composites; and nickel or other low-cost multilayer coatings. In reviewing medium and high-temperature research, black chrome, multilayer coatings and black cobalt are seen as best medium-temperature candidates. For high temperatures, an Al2O3/Pt-Al203 multilayer composite or the zirconium diboride coating is preferred.

  5. Biomimetic soluble collagen purified from bones.

    PubMed

    Ferreira, Ana Marina; Gentile, Piergiorgio; Sartori, Susanna; Pagliano, Cristina; Cabrele, Chiara; Chiono, Valeria; Ciardelli, Gianluca

    2012-11-01

    Type I collagen has been extensively exploited as a biomaterial for biomedical applications and drug delivery; however, small molecular alterations occurring during the isolation procedure and its interaction with residual bone extracellular matrix molecules or proteins might affect the overall material biocompatibility and performance. The aim of the current work is to study the potential alterations in collagen properties and organization associated with the absence of proteoglycans, which mimic pathological conditions associated with age-related diseases. A new approach for evaluating the effect of proteoglycans on the properties of isolated type I collagen from the bone matrix is described. Additional treatment with guanidine hydrochloride was introduced to remove residual proteoglycans from the collagen matrix. The properties of the isolated collagen with/without guanidine hydrochloride treatment were investigated and compared with a commercial rabbit collagen as control. We demonstrate that the absence of proteoglycans in the isolated type I collagen affects its thermal properties, the extraction into its native structure, and its ability to hydrate and self-assemble into fibers. The fine control and tuning of all these features, linked to the absence of non-collagenous proteins as proteoglycans, offer the possibility of designing new strategies and biomaterials with advanced biomimetic properties aimed at regenerating bone tissue in the case of fragility and/or defects. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Exploiting oleuropein for inhibiting collagen fibril formation.

    PubMed

    Bharathy, H; Fathima, N Nishad

    2017-08-01

    Collagen fibrils accumulate in excessive amounts and impair the normal functioning of the organ; therefore it stimulates the interest for identifying the compounds that could prevent the formation of fibrils. Herein, inhibition of self-assembly of collagen using oleuropein has been studied. The changes in the physico-chemical characteristics of collagen on interaction with increasing concentration of oleuropein has been studied using techniques like viscosity, UV-vis, CD and FT-IR. The inhibitory effect of oleuropein on fibril formation of collagen was proved using SEM. Circular dichroism and FT-IR spectra elucidates the alterations in the secondary structure of collagen suggesting non-covalent interactions between oleuropein and collagen. The decreased rate of collagen fibril formation also confirms the inhibition in the self-assembly of collagen. Hence, our study suggests that inhibition of the self-assembly process using oleuropein may unfold new avenues to treat fibrotic diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Collagen solubility correlates with skin optical clearing.

    PubMed

    Hirshburg, Jason; Choi, Bernard; Nelson, J Stuart; Yeh, Alvin T

    2006-01-01

    Biomedical optics and photomedicine applications are challenged by the turbidity of most biological tissue systems. Nonreactive, biocompatible chemical agents can induce a reversible reduction in optical scattering of collagenous tissues such as human skin. Herein we show that a chemical agent's tissue optical clearing potential is directly related to its collagen solubility, providing a rational design basis for effective, percutaneous formulations.

  8. Adaptive inertial shock-absorber

    NASA Astrophysics Data System (ADS)

    Faraj, Rami; Holnicki-Szulc, Jan; Knap, Lech; Seńko, Jarosław

    2016-03-01

    This paper introduces and discusses a new concept of impact absorption by means of impact energy management and storage in dedicated rotating inertial discs. The effectiveness of the concept is demonstrated in a selected case-study involving spinning management, a recently developed novel impact-absorber. A specific control technique performed on this device is demonstrated to be the main source of significant improvement in the overall efficiency of impact damping process. The influence of various parameters on the performance of the shock-absorber is investigated. Design and manufacturing challenges and directions of further research are formulated.

  9. Damage tolerant light absorbing material

    DOEpatents

    Lauf, Robert J.; Hamby, Jr., Clyde; Akerman, M. Alfred; Seals, Roland D.

    1993-01-01

    A light absorbing article comprised of a composite of carbon-bonded carbon fibers, prepared by: blending carbon fibers with a carbonizable organic powder to form a mixture; dispersing the mixture into an aqueous slurry; vacuum molding the aqueous slurry to form a green article; drying and curing the green article to form a cured article; and, carbonizing the cured article at a temperature of at least about 1000.degree. C. to form a carbon-bonded carbon fiber light absorbing composite article having a bulk density less than 1 g/cm.sup.3.

  10. Damage tolerant light absorbing material

    DOEpatents

    Lauf, R.J.; Hamby, C. Jr.; Akerman, M.A.; Seals, R.D.

    1993-09-07

    A light absorbing article comprised of a composite of carbon-bonded carbon fibers, is prepared by: blending carbon fibers with a carbonizable organic powder to form a mixture; dispersing the mixture into an aqueous slurry; vacuum molding the aqueous slurry to form a green article; drying and curing the green article to form a cured article; and, carbonizing the cured article at a temperature of at least about 1000 C to form a carbon-bonded carbon fiber light absorbing composite article having a bulk density less than 1 g/cm[sup 3]. 9 figures.

  11. Matrix metalloproteinase interactions with collagen and elastin.

    PubMed

    Van Doren, Steven R

    2015-01-01

    Most abundant in the extracellular matrix are collagens, joined by elastin that confers elastic recoil to the lung, aorta, and skin. These fibrils are highly resistant to proteolysis but can succumb to a minority of the matrix metalloproteinases (MMPs). Considerable inroads to understanding how such MMPs move to the susceptible sites in collagen and then unwind the triple helix of collagen monomers have been gained. The essential role in unwinding of the hemopexin-like domain of interstitial collagenases or the collagen binding domain of gelatinases is highlighted. Elastolysis is also facilitated by the collagen binding domain in the cases of MMP-2 and MMP-9, and remote exosites of the catalytic domain in the case of MMP-12. Copyright © 2015. Published by Elsevier B.V.

  12. Proline puckering parameters for collagen structure simulations

    SciTech Connect

    Wu, Di, E-mail: diwu@fudan.edu.cn

    Collagen is made of triple helices rich in proline residues, and hence is influenced by the conformational motions of prolines. Because the backbone motions of prolines are restricted by the helical structures, the only side chain motion—proline puckering—becomes an influential factor that may affect the stability of collagen structures. In molecular simulations, a proper proline puckering population is desired so to yield valid results of the collagen properties. Here we design the proline puckering parameters in order to yield suitable proline puckering populations as demonstrated in the experimental results. We test these parameters in collagen and the proline dipeptide simulations.more » Compared with the results of the PDB and the quantum calculations, we propose the proline puckering parameters for the selected collagen model simulations.« less

  13. Effects of ingestion of collagen peptide on collagen fibrils and glycosaminoglycans in the dermis.

    PubMed

    Matsuda, Naoya; Koyama, Yoh-ichi; Hosaka, Yoshinao; Ueda, Hiromi; Watanabe, Takafumi; Araya, Takayuki; Irie, Shinkichi; Takehana, Kazushige

    2006-06-01

    In order to investigate the effects of collagen peptide ingestion on fibroblasts and the extracellular matrix in the dermis, collagen peptide was administered orally to pigs at 0.2 g/kg body weight/d for 62 d, and its effects were compared with those of lactalbumin and water controls. Fibroblast density, and diameter and density of collagen fibrils were significantly larger in the collagen peptide group than in the lactalbumin and water control groups. The two major components of dermal glycosaminoglycans, hyaluronic acid and dermatan sulfate, which are present in the inter-fibrillar space, did not differ significantly among the three groups. However, the ratio of dermatan sulfate, which is derived from fibril-bound decorin, was largest in the collagen peptide group. These results suggest that ingestion of collagen peptide induces increased fibroblast density and enhances formation of collagen fibrils in the dermis in a protein-specific manner.

  14. Molecular level detection and localization of mechanical damage in collagen enabled by collagen hybridizing peptides.

    PubMed

    Zitnay, Jared L; Li, Yang; Qin, Zhao; San, Boi Hoa; Depalle, Baptiste; Reese, Shawn P; Buehler, Markus J; Yu, S Michael; Weiss, Jeffrey A

    2017-03-22

    Mechanical injury to connective tissue causes changes in collagen structure and material behaviour, but the role and mechanisms of molecular damage have not been established. In the case of mechanical subfailure damage, no apparent macroscale damage can be detected, yet this damage initiates and potentiates in pathological processes. Here, we utilize collagen hybridizing peptide (CHP), which binds unfolded collagen by triple helix formation, to detect molecular level subfailure damage to collagen in mechanically stretched rat tail tendon fascicle. Our results directly reveal that collagen triple helix unfolding occurs during tensile loading of collagenous tissues and thus is an important damage mechanism. Steered molecular dynamics simulations suggest that a likely mechanism for triple helix unfolding is intermolecular shearing of collagen α-chains. Our results elucidate a probable molecular failure mechanism associated with subfailure injuries, and demonstrate the potential of CHP targeting for diagnosis, treatment and monitoring of tissue disease and injury.

  15. Synthesis of highly interconnected 3D scaffold from Arothron stellatus skin collagen for tissue engineering application.

    PubMed

    Ramanathan, Giriprasath; Singaravelu, Sivakumar; Raja, M D; Sivagnanam, Uma Tiruchirapalli

    2015-11-01

    The substrate which is avidly used for tissue engineering applications should have good mechanical and biocompatible properties, and all these parameters are often considered as essential for dermal reformation. Highly interconnected three dimensional (3D) wound dressing material with enhanced structural integrity was synthesized from Arothron stellatus fish skin (AsFS) collagen for tissue engineering applications. The synthesized 3D collagen sponge (COL-SPG) was further characterized by different physicochemical methods. The scanning electron microscopy analysis of the material demonstrated that well interconnected pores with homogeneous microstructure on the surface aids higher swelling index and that the material also possessed good mechanical properties with a Young's modulus of 0.89±0.2 MPa. Biocompatibility of the 3D COL-SPG showed 92% growth for both NIH 3T3 fibroblasts and keratinocytes. Overall, the study revealed that synthesized 3D COL-SPG from fish skin will act as a promising wound dressing in skin tissue engineering. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Study on the development trend and practice of sponge cities with Chinese Characteristics

    NASA Astrophysics Data System (ADS)

    Lu, Baihao; Zhang, Cunkuan; Lin, Hua

    2018-03-01

    The design of sponge city is the innovation and development of theory of rainwater utilization, which provides a new idea for the city to solve the problem of waterlogging and water shortage. The paper expounds the “sponge city” concept of the origins, development and application in engineering construction, and puts forward some suggestions for future research of “sponge city” for our city construction.

  17. Counterflow absorber for an absorption refrigeration system

    DOEpatents

    Reimann, Robert C.

    1984-01-01

    An air-cooled, vertical tube absorber for an absorption refrigeration system is disclosed. Strong absorbent solution is supplied to the top of the absorber and refrigerant vapor is supplied to the bottom of the absorber to create a direct counterflow of refrigerant vapor and absorbent solution in the absorber. The refrigeration system is designed so that the volume flow rate of refrigerant vapor in the tubes of the absorber is sufficient to create a substantially direct counterflow along the entire length of each tube in the absorber. This provides several advantages for the absorber such as higher efficiency and improved heat transfer characteristics, and allows improved purging of non-condensibles from the absorber.

  18. Oil and fat absorbing polymers

    NASA Technical Reports Server (NTRS)

    Marsh, H. E., Jr. (Inventor)

    1977-01-01

    A method is described for forming a solid network polymer having a minimal amount of crosslinking for use in absorbing fats and oils. The polymer remains solid at a swelling ratio in oil or fat of at least ten and provides an oil absorption greater than 900 weight percent.

  19. Immunosuppressive compounds from a deep water marine sponge, Agelas flabelliformis.

    PubMed

    Gunasekera, S P; Cranick, S; Longley, R E

    1989-01-01

    Two immunosuppressive compounds, 4 alpha-methyl-5 alpha-cholest-8-en-3 beta-ol and 4,5-dibromo-2-pyrrolic acid were isolated from a deep water marine sponge, Agelas flabelliformis. Their structures were determined by comparison of their spectral data with those of samples isolated from other organisms. Both compounds were highly active in suppression of the response of murine splenocytes in the two-way mixed lymphocyte reaction (MLR) with little to no demonstrable cytotoxicity at lower doses. In addition, 4,5-dibromo-2-pyrrolic acid suppressed the proliferative response of splenocytes to suboptimal concentrations of the mitogen, concanavalin A (Con A). These results describe for the first time compounds isolated from the marine sponge A. flabelliformis that possess potent in vitro immunosuppressive activity.

  20. A first exploration of genome size diversity in sponges.

    PubMed

    Jeffery, Nicholas W; Jardine, Catherine B; Gregory, T Ryan

    2013-08-01

    The phyla known as early-branching lineages of animals have become the subject of increasing interest from the perspectives of genomics and evolutionary biology. Unfortunately, data on even the most fundamental properties of their genomes, such as genome size, remain very scarce. In this study, genome size estimates are reported for 75 species of sponges (phylum Porifera) representing 33 families and 12 orders, marking the first large survey of genome size diversity for an early-branching phylum. Sponge genome sizes averaged around 0.2 pg but exhibited a 17-fold range overall (0.04-0.63 pg). In addition, the results of comparisons of two methods of genome size quantification (flow cytometry and Feulgen image analysis densitometry) are presented, thereby facilitating future work on these animals. Some particularly promising avenues for future investigation are highlighted.

  1. NOAA to develop strategy to protect coral and sponge habitat

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    The U.S. National Marine Fisheries Service (NMFS) will develop a strategy to address research, conservation, and management issues regarding deep-ocean coral and sponge habitat, the agency indicated in an 11 July Federal Register notice. The Service, which is a unit of the National Oceanic and Atmospheric Administration, indicated that this strategy “eventually may result in rulemaking for some fisheries” but that “emergency rulemaking is not warranted.”The NMFS announcement is in response to a 24 March 2004 petition to the Commerce Department filed by Oceana, a non-governmental organization. That petition urged the department through NMFS to “initiate immediate rulemaking” to protect coral and sponge habitats in the U.S. exclusive economic zone through mapping, monitoring, research, and enforcement measures.

  2. NOAA to develop strategy to protect coral and sponge habitat

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    The U.S. National Marine Fisheries Service (NMFS) will develop a strategy to address research, conservation, and management issues regarding deep-ocean coral and sponge habitat, the agency indicated in an 11 July Federal Register notice. The Service, which is a unit of the National Oceanic and Atmospheric Administration, indicated that this strategy "eventually may result in rulemaking for some fisheries" but that "emergency rulemaking is not warranted."The NMFS announcement is in response to a 24 March 2004 petition to the Commerce Department filed by Oceana, a non-governmental organization. That petition urged the department through NMFS to "initiate immediate rulemaking" to protect coral and sponge habitats in the U.S. exclusive economic zone through mapping, monitoring, research, and enforcement measures.

  3. Antifouling activities of marine bacteria associated with sponge ( Sigmadocia sp.)

    NASA Astrophysics Data System (ADS)

    Satheesh, S.; Soniamby, A. R.; Sunjaiy Shankar, C. V.; Mary Josephine Punitha, S.

    2012-09-01

    The present study aimed at assessing the antifouling activity of bacteria associated with marine sponges. A total of eight bacterial strains were isolated from the surface of sponge Sigmadocia sp., of them, SS02, SS05 and SS06 showed inhibitory activity against biofilm-forming bacteria. The extracts of these 3 strains considerably affected the extracellular polymeric substance producing ability and adhesion of biofilm-forming bacterial strains. In addition to disc diffusion assay, microalgal settlement assay was carried out with the extracts mixed with polyurethane wood polish and coated onto stainless steel coupons. The extract of strain SS05 showed strong microalgal settlement inhibitory activity. Strain SS05 was identified as Bacillus cereus based on its 16S rRNA gene. Metabolites of the bacterial strains associated with marine invertebrates promise to be developed into environment-friendly antifouling agents.

  4. Chitosan-hyaluronic acid/nano silver composite sponges for drug resistant bacteria infected diabetic wounds.

    PubMed

    Anisha, B S; Biswas, Raja; Chennazhi, K P; Jayakumar, R

    2013-11-01

    The aim of this work was to develop an antimicrobial sponge composed of chitosan, hyaluronic acid (HA) and nano silver (nAg) as a wound dressing for diabetic foot ulcers (DFU) infected with drug resistant bacteria. nAg (5-20 nm) was prepared and characterized. The nanocomposite sponges were prepared by homogenous mixing of chitosan, HA and nAg followed by freeze drying to obtain a flexible and porous structure. The prepared sponges were characterized using SEM and FT-IR. The porosity, swelling, biodegradation and haemostatic potential of the sponges were also studied. Antibacterial activity of the prepared sponges was analysed using Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Klebsiella pneumonia. Chitosan-HA/nAg composite sponges showed potent antimicrobial property against the tested organisms. Sponges containing higher nAg (0.005%, 0.01% and 0.02%) concentrations showed antibacterial activity against MRSA. Cytotoxicity and cell attachment studies were done using human dermal fibroblast cells. The nanocomposite sponges showed a nAg concentration dependent toxicity towards fibroblast cells. Our results suggest that this nanocomposite sponges could be used as a potential material for wound dressing for DFU infected with antibiotic resistant bacteria if the optimal concentration of nAg exhibiting antibacterial action with least toxicity towards mammalian cells is identified. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Radiofrequency-Based Identification Medical Device: An Evaluable Solution for Surgical Sponge Retrieval?

    PubMed

    Lazzaro, Alessandra; Corona, Arianna; Iezzi, Luca; Quaresima, Silvia; Armisi, Luca; Piccolo, Ilaria; Medaglia, Carlo Maria; Sbrenni, Sergio; Sileri, Pierpaolo; Rosato, Nicola; Gaspari, Achille Lucio; Di Lorenzo, Nicola

    2017-06-01

    A retained surgical item in patients (gossypiboma) is a persisting problem, despite consistent improvements and existing guidelines in counting instruments and sponges. Previous experiences with radiofrequency identification technology (RFID) tracking sponges show that it could represent an innovation, in order to reduce the criticism and increase the effectiveness during surgical procedures. We present an automated system that allows reduction of errors and improves safety in the operating room. The system consists of 3 antennas, surgical sponges containing RFID tags, and dedicated software applications, with Wi-Fi real-time communication between devices. The first antenna provides the initial count of gauzes; the second a real-time counting during surgery, including the sponges thrown into the kick-bucket; and the third can be used in the event of uneven sponge count. The software allows management at all stages of the process. In vitro and in vivo tests were performed: the system provided excellent results in detecting sponges in patients' body. Hundred percent retained sponges were detected correctly, even when they were overlapped. No false positive or false negative was recorded. The counting procedure turned out to be more streamlined and efficient and it could save time in a standard procedure. The RFID system for sponge tracking was shown to be experimentally a reliable and feasible method to track sponges with a full detection accuracy in the operating room. The results indicate the system to be safe and effective with acceptable cost-effective parameters.

  6. Sponges-Cyanobacteria associations: Global diversity overview and new data from the Eastern Mediterranean

    PubMed Central

    Konstantinou, Despoina; Gerovasileiou, Vasilis; Voultsiadou, Eleni

    2018-01-01

    Sponge-cyanobacteria associations have attracted research interest from an ecological, evolutionary and biotechnological perspective. Current knowledge is, in its majority, “hidden” in metagenomics research studying the entire microbial communities of sponges, while knowledge on these associations is totally missing for certain geographic areas. In this study, we (a) investigated the occurrence of cyanobacteria in 18 sponge species, several of which are studied for the first time for their cyanobionts, from a previously unexplored eastern Mediterranean ecoregion, the Aegean Sea, (b) isolated sponge-associated cyanobacteria, and characterized them based on a polyphasic (morphological-morphometric and molecular phylogenetic analysis) approach, and (c) conducted a meta-analysis on the global diversity of sponge species hosting cyanobacteria, as well as the diversity of cyanobacterial symbionts. Our research provided new records for nine sponge species, previously unknown for this association, while the isolated cyanobacteria were found to form novel clades within Synechococcus, Leptolyngbyaceae, Pseudanabaenaceae, and Schizotrichaceae, whose taxonomic status requires further investigation; this is the first report of a Schizotrichaceae cyanobacterium associated with sponges. The extensive evaluation of the literature along with the new data from the Aegean Sea raised the number of sponge species known for hosting cyanobacteria to 320 and showed that the cyanobacterial diversity reported from sponges is yet underestimated. PMID:29596453

  7. Comparisons of the fungal and protistan communities among different marine sponge holobionts by pyrosequencing.

    PubMed

    He, Liming; Liu, Fang; Karuppiah, Valliappan; Ren, Yi; Li, Zhiyong

    2014-05-01

    To date, the knowledge of eukaryotic communities associated with sponges remains limited compared with prokaryotic communities. In a manner similar to prokaryotes, it could be hypothesized that sponge holobionts have phylogenetically diverse eukaryotic symbionts, and the eukaryotic community structures in different sponge holobionts were probably different. In order to test this hypothesis, the communities of eukaryota associated with 11 species of South China Sea sponges were compared with the V4 region of 18S ribosomal ribonucleic acid gene using 454 pyrosequencing. Consequently, 135 and 721 unique operational taxonomic units (OTUs) of fungi and protists were obtained at 97 % sequence similarity, respectively. These sequences were assigned to 2 phyla of fungi (Ascomycota and Basidiomycota) and 9 phyla of protists including 5 algal phyla (Chlorophyta, Haptophyta, Streptophyta, Rhodophyta, and Stramenopiles) and 4 protozoal phyla (Alveolata, Cercozoa, Haplosporidia, and Radiolaria) including 47 orders (12 fungi, 35 protists). Entorrhizales of fungi and 18 orders of protists were detected in marine sponges for the first time. Particularly, Tilletiales of fungi and Chlorocystidales of protists were detected for the first time in marine habitats. Though Ascomycota, Alveolata, and Radiolaria were detected in all the 11 sponge species, sponge holobionts have different fungi and protistan communities according to OTU comparison and principal component analysis at the order level. This study provided the first insights into the fungal and protistan communities associated with different marine sponge holobionts using pyrosequencing, thus further extending the knowledge on sponge-associated eukaryotic diversity.

  8. Glycosides from Marine Sponges (Porifera, Demospongiae): Structures, Taxonomical Distribution, Biological Activities and Biological Roles

    PubMed Central

    Kalinin, Vladimir I.; Ivanchina, Natalia V.; Krasokhin, Vladimir B.; Makarieva, Tatyana N.; Stonik, Valentin A.

    2012-01-01

    Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed. PMID:23015769

  9. Chemical versus mechanical bioerosion of coral reefs by boring sponges--lessons from Pione cf. vastifica.

    PubMed

    Zundelevich, A; Lazar, B; Ilan, M

    2007-01-01

    Bioerosion by boring sponges is an important mechanism shaping the structure of coral reefs all around the world. To determine the excavation rate by boring sponges, we developed a system in which chemical and mechanical boring rates [calcium carbonate (CaCO(3)) dissolution and chip production, respectively] were measured simultaneously in experimental tanks containing reefal rock inhabited by a boring sponge. Pione cf. vastifica (Hancock 1849) was chosen as a model species to study the erosion rate of boring sponges. It is an abundant species in the coral reefs of the Nature Reserve Reef, Elat, Gulf of Aqaba, northern Red Sea, reaching maximum abundance at 25-30 m. The rate of chemical bioerosion was determined from the increase in tank-seawater alkalinity over time, and the mechanical bioerosion rate was estimated from the total amount of CaCO(3) chips produced over the same time interval. The measured bioerosion rate of P. cf. vastifica was 2.3 g m(-2) sponge day(-1), showing seasonal but not diurnal variations, suggesting that the zooxanthellae harboring the sponge have no effect on its boring rate. The experiments indicated clearly that per each mass of chips that P. cf. vastifica produces during its boring activity, it dissolves three masses of reef CaCO(3) framework. Assuming that some additional boring sponges can use a similar strategy of bioerosion, these findings suggest that chips, the most obvious erosion products of boring sponges, represent only a small fraction of boring sponge bioerosion capacity.

  10. Mediterranean sponges from shallow subtidal rocky reefs: Cystoseira canopy vs barren grounds

    NASA Astrophysics Data System (ADS)

    Costa, Gabriele; Bertolino, Marco; Pinna, Stefania; Bonaviri, Chiara; Padiglia, Andrea; Zinni, Matteo; Pronzato, Roberto; Manconi, Renata

    2018-07-01

    Porifera richness was investigated in Cystoseira canopies vs barren grounds considering different substrates at 6 areas in the Central-Western Mediterranean Sea. In total 31 sponge taxa were recorded at 2-7 m depth and the sponge community structure and composition were characterized by a notably low richness with 25 taxa in the Cystoseira forest and 15 in the barren area. As for the sponge habitus, the massive sponges were dominant in both facies, whereas encrusting, and cavity dwelling sponges were found in higher numbers in the Cystoseira forest. Results revealed that rocky substrata seem to play a key role in driving the sponge community composition and diversity in both facies. In this work we explore the role of Cystoseira canopy as a suitable facies for sponges. Sponge assemblages were persistent, strongly resilient in space occupation and consequently support stability in both facies. Some species seem to be pre-adapted to live under the sub-optimal conditions of the barren grounds, i.e. the absence of the Cystoseira fronds shelter. This focus on sponge successful eco-etological performances in 'submarine deserts' such as barren areas shows features as shown in a few other sessile benthic invertebrates.

  11. Spatial and temporal variation in sponge spicule patches at Station M, northeast Pacific.

    PubMed

    Laguionie-Marchais, C; Kuhnz, L A; Huffard, C L; Ruhl, H A; Smith, K L

    Changes in habitat-forming organisms can have complex consequences for associated species. Sessile epibenthic glass "plate" sponges (Porifera: Hexactinellida) are conspicuous inhabitants of soft-sediment abyssal areas and their siliceous spicules create persistent spicule patches on the seafloor. Sponge spicule patch density, spatial dispersion, and percent cover were examined over a seven-year period (2006-2013) using remotely operated vehicle videos from Station M in the abyssal northeast Pacific (50˚00N, 123˚00W, ~4,000 m depth). There was an apparent large increase in newly dead plate sponges in February 2007 compared with December 2006, with this trend continuing through June 2007 (mean 0.03 % cover increasing to 0.33 %). A second increase in mean percent cover of dead plate sponges occurred from May 2011 (0.24 %) through June 2012 (0.60 %). Among the 28 megafaunal taxa occurring in association with the patches, the distributions of three taxa [two sponge taxa (Porifera) and brittle stars (Ophiuroidea)] suggested selectivity for the sponge spicule patches. The community structure of visible megafauna within sponge spicule patches was different when compared with that outside the patches suggesting that the sponges, after death, provide preferred habitat patches for certain benthic megafauna. These findings indicate that sponge spicule patches contribute to habitat heterogeneity in space and time.

  12. Drivers of epibenthic megafaunal composition in the sponge grounds of the Sackville Spur, northwest Atlantic

    NASA Astrophysics Data System (ADS)

    Beazley, Lindsay; Kenchington, Ellen; Yashayaev, Igor; Murillo, Francisco Javier

    2015-04-01

    Deep-water sponges are considered ecosystem engineers, and the presence of large aggregations of these organisms, commonly referred to as sponge grounds, is associated with enhanced biodiversity and abundance of epibenthic fauna compared to non-sponge habitat. However, the degree and magnitude to which the presence of these sponge grounds elicits large changes in composition of the associated megafaunal community remains unknown. Here we identify the external drivers of epibenthic megafaunal community composition and explore the patterns and magnitude of compositional change in the megafaunal community within the sponge grounds of the Sackville Spur, northwest Atlantic. Epibenthic megafauna were quantified from five image transects collected on the Sackville Spur in 2009 between 1080 and 1723 m depth. Using Gradient Forest Modelling we found that the abundance of structure-forming sponges was the most important variable for predicting compositional patterns in the Sackville Spur megafaunal community, followed by depth, range in bottom current speed, in situ salinity, and longitude. Along the gradient in structure-forming sponge abundance, the largest turnover in megafaunal community composition occurred when the sponges reached 15 individuals m-2. Examination of the regional hydrographic conditions suggests that the dense sponge grounds of the Sackville Spur are associated with a warm, salty water mass that occurs between ~1300 and 1800 m.

  13. Origin and Evolution of the Sponge Aggregation Factor Gene Family.

    PubMed

    Grice, Laura F; Gauthier, Marie E A; Roper, Kathrein E; Fernàndez-Busquets, Xavier; Degnan, Sandie M; Degnan, Bernard M

    2017-05-01

    Although discriminating self from nonself is a cardinal animal trait, metazoan allorecognition genes do not appear to be homologous. Here, we characterize the Aggregation Factor (AF) gene family, which encodes putative allorecognition factors in the demosponge Amphimedon queenslandica, and trace its evolution across 24 sponge (Porifera) species. The AF locus in Amphimedon is comprised of a cluster of five similar genes that encode Calx-beta and Von Willebrand domains and a newly defined Wreath domain, and are highly polymorphic. Further AF variance appears to be generated through individualistic patterns of RNA editing. The AF gene family varies between poriferans, with protein sequences and domains diagnostic of the AF family being present in Amphimedon and other demosponges, but absent from other sponge classes. Within the demosponges, AFs vary widely with no two species having the same AF repertoire or domain organization. The evolution of AFs suggests that their diversification occurs via high allelism, and the continual and rapid gain, loss and shuffling of domains over evolutionary time. Given the marked differences in metazoan allorecognition genes, we propose the rapid evolution of AFs in sponges provides a model for understanding the extensive diversification of self-nonself recognition systems in the animal kingdom. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  14. Origin and Evolution of the Sponge Aggregation Factor Gene Family

    PubMed Central

    Grice, Laura F.; Gauthier, Marie E.A.; Roper, Kathrein E.; Fernàndez-Busquets, Xavier; Degnan, Sandie M.

    2017-01-01

    Although discriminating self from nonself is a cardinal animal trait, metazoan allorecognition genes do not appear to be homologous. Here, we characterize the Aggregation Factor (AF) gene family, which encodes putative allorecognition factors in the demosponge Amphimedon queenslandica, and trace its evolution across 24 sponge (Porifera) species. The AF locus in Amphimedon is comprised of a cluster of five similar genes that encode Calx-beta and Von Willebrand domains and a newly defined Wreath domain, and are highly polymorphic. Further AF variance appears to be generated through individualistic patterns of RNA editing. The AF gene family varies between poriferans, with protein sequences and domains diagnostic of the AF family being present in Amphimedon and other demosponges, but absent from other sponge classes. Within the demosponges, AFs vary widely with no two species having the same AF repertoire or domain organization. The evolution of AFs suggests that their diversification occurs via high allelism, and the continual and rapid gain, loss and shuffling of domains over evolutionary time. Given the marked differences in metazoan allorecognition genes, we propose the rapid evolution of AFs in sponges provides a model for understanding the extensive diversification of self–nonself recognition systems in the animal kingdom. PMID:28104746

  15. The Size of Gelatin Sponge Particles: Differences with Preparation Method

    SciTech Connect

    Katsumori, Tetsuya, E-mail: katsumo@eurus.dti.ne.jp; Kasahara, Toshiyuki

    2006-12-15

    Purpose. To assess whether the size distribution of gelatin sponge particles differed according to the method used to make them and the type of original sheet. Methods. Gelatin sponge particles of approximately 1-1.5 x 1-1.5 x 2 mm were made from either Spongel or Gelfoam sheets by cutting with a scalpel and scissors. Particles were also made of either Spongel or Gelfoam sheets by pumping with two syringes and a three-way stopcock. The size distribution of the particles in saline was compared among the groups. Results. (1) Cutting versus pumping: When Spongel was used, cutting produced lower rates of smallermore » particles {<=}500 {mu}m and larger particles >2000 {mu}m compared with pumping back and forth 30 times (1.1% vs 37.6%, p < 0.0001; 2.2% vs 14.4%, p = 0.008). When Gelfoam was used, cutting produced lower rates of smaller and larger particles compared with pumping (8.5% vs 20.4%, p = 0.1809; 0% vs 48.1%, p < 0.0001). (2) Spongel versus Gelfoam: There was no significant difference in the size distribution of the particles between Spongel and Gelfoam (p = 0.2002) when cutting was used. Conclusion. The size distribution of gelatin sponge particles differed according to the method used to make them. More uniform particle sizes can be achieved by cutting than by pumping.« less

  16. Secondary Metabolites from Three Florida Sponges with Antidepressant Activity

    PubMed Central

    Kochanowska, Anna J.; Rao, Karumanchi V.; Childress, Suzanne; El-Alfy, Abir; Matsumoto, Rae R.; Kelly, Michelle; Stewart, Gina S.; Sufka, Kenneth J.; Hamann, Mark T.

    2016-01-01

    Brominated indole alkaloids are a common class of metabolites reported from sponges of the order Verongida. Herein we report the isolation, structure determination, and activity of metabolites from three Florida sponges, namely, Verongula rigida (order Verongida, family Aplysinidae), Smenospongia aurea, and S. cerebriformis (order Dictyoceratida, family Thorectidae). All three species were investigated chemically, revealing similarities in secondary metabolites. Brominated compounds, as well as sesquiterpene quinones and hydroquinones, were identified from both V. rigida and S. aurea despite their apparent taxonomic differences at the ordinal level. Similar metabolites found in these distinct sponge species of two different genera provide evidence for a microbial origin of the metabolites. Isolated compounds were evaluated in the Porsolt forced swim test (FST) and the chick anxiety–depression continuum model. Among the isolated compounds, 5,6-dibromo-N,N-dimethyltryptamine (1) exhibited significant antidepressant-like action in the rodent FST model, while 5-bromo-N,N-dimethyltryptamine (2) caused significant reduction of locomotor activity indicative of a potential sedative action. The current study provides ample evidence that marine natural products with the diversity of brominated marine alkaloids will provide potential leads for antidepressant and anxiolytic drugs. PMID:18217716

  17. Secondary metabolites from three Florida sponges with antidepressant activity.

    PubMed

    Kochanowska, Anna J; Rao, Karumanchi V; Childress, Suzanne; El-Alfy, Abir; Matsumoto, Rae R; Kelly, Michelle; Stewart, Gina S; Sufka, Kenneth J; Hamann, Mark T

    2008-02-01

    Brominated indole alkaloids are a common class of metabolites reported from sponges of the order Verongida. Herein we report the isolation, structure determination, and activity of metabolites from three Florida sponges, namely, Verongula rigida (order Verongida, family Aplysinidae), Smenospongia aurea, and S. cerebriformis (order Dictyoceratida, family Thorectidae). All three species were investigated chemically, revealing similarities in secondary metabolites. Brominated compounds, as well as sesquiterpene quinones and hydroquinones, were identified from both V. rigida and S. aurea despite their apparent taxonomic differences at the ordinal level. Similar metabolites found in these distinct sponge species of two different genera provide evidence for a microbial origin of the metabolites. Isolated compounds were evaluated in the Porsolt forced swim test (FST) and the chick anxiety-depression continuum model. Among the isolated compounds, 5,6-dibromo- N,N-dimethyltryptamine ( 1) exhibited significant antidepressant-like action in the rodent FST model, while 5-bromo- N,N-dimethyltryptamine ( 2) caused significant reduction of locomotor activity indicative of a potential sedative action. The current study provides ample evidence that marine natural products with the diversity of brominated marine alkaloids will provide potential leads for antidepressant and anxiolytic drugs.

  18. Preparation and characterization of composites based on the blends of collagen, chitosan and hyaluronic acid with nano-hydroxyapatite.

    PubMed

    Sionkowska, Alina; Kaczmarek, Beata

    2017-09-01

    3D porous composites based on the blend of chitosan, collagen and hyaluronic acid with the addition of nano-hydroxyapatite were prepared. SEM images for the composites were made and the structure was assessed. Mechanical properties were studied using a Zwick&Roell Testing Mashine. In addition, the porosity and density of composites were measured. The concentration of calcium ions released from the material was detected by the complexometric titration method. The results showed that in 3D porous sponge based on the blend of chitosan, collagen and hyaluronic acid, inorganic particles of nanohydroxyapatite can be incorporated, as well as that the properties of 3D composites depend on the material composition. Mechanical parameters and thermal stability of ternary biopolymeric blends were improved by the addition of hydroxyapatite. Moreover, the porosity of ternary materials was higher than in materials based on pure chitosan or collagen. All composites were characterized by a porous structure with interconnected pores. Calcium ions can be released from the composite during its degradation in water. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. In vivo evaluation of hybrid patches composed of PLA based copolymers and collagen/chondroitin sulfate for ligament tissue regeneration.

    PubMed

    Pinese, Coline; Gagnieu, Christian; Nottelet, Benjamin; Rondot-Couzin, Capucine; Hunger, Sylvie; Coudane, Jean; Garric, Xavier

    2017-10-01

    Biomaterials for soft tissues regeneration should exhibit sufficient mechanical strength, demonstrating a mechanical behavior similar to natural tissues and should also promote tissues ingrowth. This study was aimed at developing new hybrid patches for ligament tissue regeneration by synergistic incorporation of a knitted structure of degradable polymer fibers to provide mechanical strength and of a biomimetic matrix to help injured tissues regeneration. PLA- Pluronic ® (PLA-P) and PLA-Tetronic ® (PLA-T) new copolymers were shaped as knitted patches and were associated with collagen I (Coll) and collagen I/chondroitine-sulfate (Coll CS) 3-dimensional matrices. In vitro study using ligamentocytes showed the beneficial effects of CS on ligamentocytes proliferation. Hybrid patches were then subcutaneously implanted in rats for 4 and 12 weeks. Despite degradation, patches retained strength to answer the mechanical physiological needs. Tissue integration capacity was assessed with histological studies. We showed that copolymers, associated with collagen and chondroitin sulfate sponge, exhibited very good tissue integration and allowed neotissue synthesis after 12 weeks in vivo. To conclude, PLA-P/CollCS and PLA-T/CollCS hybrid patches in terms of structure and composition give good hopes for tendon and ligament regeneration. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1778-1788, 2017. © 2016 Wiley Periodicals, Inc.

  20. [Study of new blended chemical absorbents to absorb CO2].

    PubMed

    Wang, Jin-Lian; Fang, Meng-Xiang; Yan, Shui-Ping; Luo, Zhong-Yang; Cen, Ke-Fa

    2007-11-01

    Three kinds of blended absorbents were investigated on bench-scale experimental bench according to absorption rate and regeneration grade to select a reasonable additive concentration. The results show that, among methyldiethanolamine (MDEA) and piperazine (PZ) mixtures, comparing MDEA : PZ = 1 : 0.4 (m : m) with MDEA : PZ = 1 : 0.2 (m : m), the absorption rate is increased by about 70% at 0.2 mol x mol(-1). When regeneration lasting for 40 min, regeneration grade of blended absorbents with PZ concentration of 0.2, 0.4, and 0.8 is decreased to 83.06%, 77.77% and 76.67% respectively while 91.04% for PZ concentration of 0. MDEA : PZ = 1 : 0.4(m : m) is a suitable ratio for MDEA/PZ mixtures as absorption and regeneration properties of the blended absorbents are all improved. The aqueous blends with 10% primary amines and 2% tertiary amines could keep high CO2 absorption rate, and lower regeneration energy consumption. Adding 2% 2-Amino-2-methyl-1-propanol (AMP) to 10% diethanolamine (DEA), the blended amine solvents have an advantage in absorption and regeneration properties over other DEA/AMP mixtures. Blended solvents, which consist of a mixture of primary amines with a small amount of tertiary amines, have the highest absorption rate among the three. And mixed absorbents of secondary amines and a small amount of sterically hindered amines have the best regeneration property. To combine absorption and regeneration properties, blends with medium activator addition to tertiary amines are competitive.

  1. Nonlinear optical response of the collagen triple helix and second harmonic microscopy of collagen liquid crystals

    NASA Astrophysics Data System (ADS)

    Deniset-Besseau, A.; De Sa Peixoto, P.; Duboisset, J.; Loison, C.; Hache, F.; Benichou, E.; Brevet, P.-F.; Mosser, G.; Schanne-Klein, M.-C.

    2010-02-01

    Collagen is characterized by triple helical domains and plays a central role in the formation of fibrillar and microfibrillar networks, basement membranes, as well as other structures of the connective tissue. Remarkably, fibrillar collagen exhibits efficient Second Harmonic Generation (SHG) and SHG microscopy proved to be a sensitive tool to score fibrotic pathologies. However, the nonlinear optical response of fibrillar collagen is not fully characterized yet and quantitative data are required to further process SHG images. We therefore performed Hyper-Rayleigh Scattering (HRS) experiments and measured a second order hyperpolarisability of 1.25 10-27 esu for rat-tail type I collagen. This value is surprisingly large considering that collagen presents no strong harmonophore in its amino-acid sequence. In order to get insight into the physical origin of this nonlinear process, we performed HRS measurements after denaturation of the collagen triple helix and for a collagen-like short model peptide [(Pro-Pro-Gly)10]3. It showed that the collagen large nonlinear response originates in the tight alignment of a large number of weakly efficient harmonophores, presumably the peptide bonds, resulting in a coherent amplification of the nonlinear signal along the triple helix. To illustrate this mechanism, we successfully recorded SHG images in collagen liquid solutions by achieving liquid crystalline ordering of the collagen triple helices.

  2. The pathobiology of collagens in glioma

    PubMed Central

    Payne, Leo S.; Huang, Paul H.

    2013-01-01

    Malignant gliomas are characterised by diffuse infiltration into the surrounding brain parenchyma. Infiltrating glioma cells exist in close proximity with components of the tumour microenvironment, including the extracellular matrix (ECM). While levels of collagens in the normal adult brain are low, in glioma, collagen levels are elevated and play an important role in driving the tumor progression. In this review, we provide a comprehensive overview of the nature of collagens found in gliomas and offer insights into the mechanisms by which cancer cells interact with this ECM via receptors including the integrins, discoidin domain receptors and Endo180. We further describe the major remodelling pathways of brain tumour collagen mediated by the matrix metalloproteinases and highlight the reciprocal relationship between these enzymes and the collagen receptors. Finally, we conclude by offering a perspective on how the biophysical properties of the collagen ECM, in particular, mechanical stiffness and compliance may influence malignant outcome. Understanding the complex interactions between glioma cells and the collagen ECM may provide new avenues to combat the rampant tumor progression and chemoresistance in brain cancer patients. PMID:23861322

  3. The Mineral–Collagen Interface in Bone

    PubMed Central

    2015-01-01

    The interface between collagen and the mineral reinforcement phase, carbonated hydroxyapatite (cAp), is essential for bone’s remarkable functionality as a biological composite material. The very small dimensions of the cAp phase and the disparate natures of the reinforcement and matrix are essential to the material’s performance but also complicate study of this interface. This article summarizes what is known about the cAp-collagen interface in bone and begins with descriptions of the matrix and reinforcement roles in composites, of the phases bounding the interface, of growth of cAp growing within the collagen matrix, and of the effect of intra- and extrafibrilar mineral on determinations of interfacial properties. Different observed interfacial interactions with cAp (collagen, water, non-collagenous proteins) are reviewed; experimental results on interface interactions during loading are reported as are their influence on macroscopic mechanical properties; conclusions of numerical modeling of interfacial interactions are also presented. The data suggest interfacial interlocking (bending of collagen molecules around cAp nanoplatelets) and water-mediated bonding between collagen and cAp are essential to load transfer. The review concludes with descriptions of areas where new research is needed to improve understanding of how the interface functions. PMID:25824581

  4. Age Increases Monocyte Adhesion on Collagen

    NASA Astrophysics Data System (ADS)

    Khalaji, Samira; Zondler, Lisa; Kleinjan, Fenneke; Nolte, Ulla; Mulaw, Medhanie A.; Danzer, Karin M.; Weishaupt, Jochen H.; Gottschalk, Kay-E.

    2017-05-01

    Adhesion of monocytes to micro-injuries on arterial walls is an important early step in the occurrence and development of degenerative atherosclerotic lesions. At these injuries, collagen is exposed to the blood stream. We are interested whether age influences monocyte adhesion to collagen under flow, and hence influences the susceptibility to arteriosclerotic lesions. Therefore, we studied adhesion and rolling of human peripheral blood monocytes from old and young individuals on collagen type I coated surface under shear flow. We find that firm adhesion of monocytes to collagen type I is elevated in old individuals. Pre-stimulation by lipopolysaccharide increases the firm adhesion of monocytes homogeneously in older individuals, but heterogeneously in young individuals. Blocking integrin αx showed that adhesion of monocytes to collagen type I is specific to the main collagen binding integrin αxβ2. Surprisingly, we find no significant age-dependent difference in gene expression of integrin αx or integrin β2. However, if all integrins are activated from the outside, no differences exist between the age groups. Altered integrin activation therefore causes the increased adhesion. Our results show that the basal increase in integrin activation in monocytes from old individuals increases monocyte adhesion to collagen and therefore the risk for arteriosclerotic plaques.

  5. Fibrous mini-collagens in hydra nematocysts.

    PubMed

    Holstein, T W; Benoit, M; Herder, G V; David, C N; Wanner, G; Gaub, H E

    1994-07-15

    Nematocysts (cnidocysts) are exocytotic organelles found in all cnidarians. Here, atomic force microscopy and field emission scanning electron microscopy reveal the structure of the nematocyst capsule wall. The outer wall consists of globular proteins of unknown function. The inner wall consists of bundles of collagen-like fibrils having a spacing of 50 to 100 nanometers and cross-striations at intervals of 32 nanometers. The fibrils consist of polymers of "mini-collagens," which are abundant in the nematocysts of Hydra. The distinct pattern of mini-collagen fibers in the inner wall can provide the tensile strength necessary to withstand the high osmotic pressure (15 megapascals) in the capsules.

  6. Chemical defenses and resource trade-offs structure sponge communities on Caribbean coral reefs

    PubMed Central

    Loh, Tse-Lynn; Pawlik, Joseph R.

    2014-01-01

    Ecological studies have rarely been performed at the community level across a large biogeographic region. Sponges are now the primary habitat-forming organisms on Caribbean coral reefs. Recent species-level investigations have demonstrated that predatory fishes (angelfishes and some parrotfishes) differentially graze sponges that lack chemical defenses, while co-occurring, palatable species heal, grow, reproduce, or recruit at faster rates than defended species. Our prediction, based on resource allocation theory, was that predator removal would result in a greater proportion of palatable species in the sponge community on overfished reefs. We tested this prediction by performing surveys of sponge and fish community composition on reefs having different levels of fishing intensity across the Caribbean. A total of 109 sponge species was recorded from 69 sites, with the 10 most common species comprising 51.0% of sponge cover (3.6–7.7% per species). Nonmetric multidimensional scaling indicated that the species composition of sponge communities depended more on the abundance of sponge-eating fishes than geographic location. Across all sites, multiple-regression analyses revealed that spongivore abundance explained 32.8% of the variation in the proportion of palatable sponges, but when data were limited to geographically adjacent locations with strongly contrasting levels of fishing pressure (Cayman Islands and Jamaica; Curaçao, Bonaire, and Martinique), the adjusted R2 values were much higher (76.5% and 94.6%, respectively). Overfishing of Caribbean coral reefs, particularly by fish trapping, removes sponge predators and is likely to result in greater competition for space between faster-growing palatable sponges and endangered reef-building corals. PMID:24567392

  7. Indirect effects of overfishing on Caribbean reefs: sponges overgrow reef-building corals.

    PubMed

    Loh, Tse-Lynn; McMurray, Steven E; Henkel, Timothy P; Vicente, Jan; Pawlik, Joseph R

    2015-01-01

    Consumer-mediated indirect effects at the community level are difficult to demonstrate empirically. Here, we show an explicit indirect effect of overfishing on competition between sponges and reef-building corals from surveys of 69 sites across the Caribbean. Leveraging the large-scale, long-term removal of sponge predators, we selected overfished sites where intensive methods, primarily fish-trapping, have been employed for decades or more, and compared them to sites in remote or marine protected areas (MPAs) with variable levels of enforcement. Sponge-eating fishes (angelfishes and parrotfishes) were counted at each site, and the benthos surveyed, with coral colonies scored for interaction with sponges. Overfished sites had >3 fold more overgrowth of corals by sponges, and mean coral contact with sponges was 25.6%, compared with 12.0% at less-fished sites. Greater contact with corals by sponges at overfished sites was mostly by sponge species palatable to sponge predators. Palatable species have faster rates of growth or reproduction than defended sponge species, which instead make metabolically expensive chemical defenses. These results validate the top-down conceptual model of sponge community ecology for Caribbean reefs, as well as provide an unambiguous justification for MPAs to protect threatened reef-building corals. An unanticipated outcome of the benthic survey component of this study was that overfished sites had lower mean macroalgal cover (23.1% vs. 38.1% for less-fished sites), a result that is contrary to prevailing assumptions about seaweed control by herbivorous fishes. Because we did not quantify herbivores for this study, we interpret this result with caution, but suggest that additional large-scale studies comparing intensively overfished and MPA sites are warranted to examine the relative impacts of herbivorous fishes and urchins on Caribbean reefs.

  8. Chemical defenses and resource trade-offs structure sponge communities on Caribbean coral reefs.

    PubMed

    Loh, Tse-Lynn; Pawlik, Joseph R

    2014-03-18

    Ecological studies have rarely been performed at the community level across a large biogeographic region. Sponges are now the primary habitat-forming organisms on Caribbean coral reefs. Recent species-level investigations have demonstrated that predatory fishes (angelfishes and some parrotfishes) differentially graze sponges that lack chemical defenses, while co-occurring, palatable species heal, grow, reproduce, or recruit at faster rates than defended species. Our prediction, based on resource allocation theory, was that predator removal would result in a greater proportion of palatable species in the sponge community on overfished reefs. We tested this prediction by performing surveys of sponge and fish community composition on reefs having different levels of fishing intensity across the Caribbean. A total of 109 sponge species was recorded from 69 sites, with the 10 most common species comprising 51.0% of sponge cover (3.6-7.7% per species). Nonmetric multidimensional scaling indicated that the species composition of sponge communities depended more on the abundance of sponge-eating fishes than geographic location. Across all sites, multiple-regression analyses revealed that spongivore abundance explained 32.8% of the variation in the proportion of palatable sponges, but when data were limited to geographically adjacent locations with strongly contrasting levels of fishing pressure (Cayman Islands and Jamaica; Curaçao, Bonaire, and Martinique), the adjusted R(2) values were much higher (76.5% and 94.6%, respectively). Overfishing of Caribbean coral reefs, particularly by fish trapping, removes sponge predators and is likely to result in greater competition for space between faster-growing palatable sponges and endangered reef-building corals.

  9. First documentation of tidal-channel sponge biostromes (upper Pleistocene, southeastern Florida)

    USGS Publications Warehouse

    Cunningham, K.J.; Rigby, J.K.; Wacker, M.A.; Curran, H.A.

    2007-01-01

    Sponges are not a common principal component of Cenozoic reefs and are more typically dominant in deep-water and/or cold-water localities. Here we report the discovery of extensive upper Pleistocene shallow-marine, tropical sponge biostromes from the Mami Limestone of southeastern Florida built by a new ceractinomorph demosponge. These upright, barrel- to vase-shaped sponges occur in monospecific aggregations constructed within the tidal channels of an oolitic tidal-bar belt similar to modern examples on the Great Bahama Bank. The biostromes appear to have a ribbon-like geometry, with densely spaced sponges populating a paleochannel along a 3.5 km extent in the most lengthy biostrome. These are very large (as high as 2 m and 1.8 m in diameter), particularly well-preserved calcified sponges with walls as hard as concrete. Quartz grains are the most common particles agglutinated in the structure of the sponge walls. Where exposed, sediment fill between the sponges is commonly a highly burrowed or cross-bedded ooid-bearing grainstone and, locally, quartz sand. It is postulated that the dense, localized distribution of these particular sponges was due to a slight edge over competitors for food or energy supply and space in a stressed environment of tidal-influenced salinity and nutrient changes, strong currents, and frequently shifting submarine sand dunes. To our knowledge, this represents the first documentation of sponge biostromes composed of very large upright sponges within high-energy tidal channels between ooid shoals. The remarkably well-preserved accumulations provide an alternative example of sponge reefs for comparative paleoenvironmental studies. ?? 2007 The Geological Society of America.

  10. Host-specificity among abundant and rare taxa in the sponge microbiome.

    PubMed

    Reveillaud, Julie; Maignien, Loïs; Murat Eren, A; Huber, Julie A; Apprill, Amy; Sogin, Mitchell L; Vanreusel, Ann

    2014-06-01

    Microbial communities have a key role in the physiology of the sponge host, and it is therefore essential to understand the stability and specificity of sponge-symbiont associations. Host-specific bacterial associations spanning large geographic distance are widely acknowledged in sponges. However, the full spectrum of specificity remains unclear. In particular, it is not known whether closely related sponges host similar or very different microbiota over wide bathymetric and geographic gradients, and whether specific associations extend to the rare members of the sponge microbiome. Using the ultra-deep Illumina sequencing technology, we conducted a comparison of sponge bacterial communities in seven closely related Hexadella species with a well-resolved host phylogeny, as well as of a distantly related sponge Mycale. These samples spanned unprecedentedly large bathymetric (15-960 m) gradients and varying European locations. In addition, this study included a bacterial community analysis of the local background seawater for both Mycale and the widespread deep-sea taxa Hexadella cf. dedritifera. We observed a striking diversity of microbes associated with the sponges, spanning 47 bacterial phyla. The data did not reveal any Hexadella microbiota co-speciation pattern, but confirmed sponge-specific and species-specific host-bacteria associations, even within extremely low abundant taxa. Oligotyping analysis also revealed differential enrichment preferences of closely related Nitrospira members in closely related sponges species. Overall, these results demonstrate highly diverse, remarkably specific and stable sponge-bacteria associations that extend to members of the rare biosphere at a very fine phylogenetic scale, over significant geographic and bathymetric gradients.

  11. Indirect effects of overfishing on Caribbean reefs: sponges overgrow reef-building corals

    PubMed Central

    Loh, Tse-Lynn; McMurray, Steven E.; Henkel, Timothy P.; Vicente, Jan

    2015-01-01

    Consumer-mediated indirect effects at the community level are difficult to demonstrate empirically. Here, we show an explicit indirect effect of overfishing on competition between sponges and reef-building corals from surveys of 69 sites across the Caribbean. Leveraging the large-scale, long-term removal of sponge predators, we selected overfished sites where intensive methods, primarily fish-trapping, have been employed for decades or more, and compared them to sites in remote or marine protected areas (MPAs) with variable levels of enforcement. Sponge-eating fishes (angelfishes and parrotfishes) were counted at each site, and the benthos surveyed, with coral colonies scored for interaction with sponges. Overfished sites had >3 fold more overgrowth of corals by sponges, and mean coral contact with sponges was 25.6%, compared with 12.0% at less-fished sites. Greater contact with corals by sponges at overfished sites was mostly by sponge species palatable to sponge predators. Palatable species have faster rates of growth or reproduction than defended sponge species, which instead make metabolically expensive chemical defenses. These results validate the top-down conceptual model of sponge community ecology for Caribbean reefs, as well as provide an unambiguous justification for MPAs to protect threatened reef-building corals. An unanticipated outcome of the benthic survey component of this study was that overfished sites had lower mean macroalgal cover (23.1% vs. 38.1% for less-fished sites), a result that is contrary to prevailing assumptions about seaweed control by herbivorous fishes. Because we did not quantify herbivores for this study, we interpret this result with caution, but suggest that additional large-scale studies comparing intensively overfished and MPA sites are warranted to examine the relative impacts of herbivorous fishes and urchins on Caribbean reefs. PMID:25945305

  12. Acetylation of loofa (Luffa cylindrica) sponge as immobilization carrier for bioprocesses involving cellulase.

    PubMed

    Hideno, Akihiro; Ogbonna, James C; Aoyagi, Hideki; Tanaka, Hideo

    2007-04-01

    The feasibility of using loofa sponge for immobilization of cellulase-producing microorganisms was investigated by acetylating loofa sponge. Acetylation was achieved by autoclaving process of loofa sponge immersed in acetic anhydride at various temperatures for various times. The degree of acetylation, as inferred by the weight percentage gain (WPG), was enhanced by increasing both temperature and the duration of acetylation. The acetylation of a piece of loofa sponge in an autoclave at 120 degrees C for 20 min resulted in a WPG of about 8%, which was sufficient to protect the loofa sponge against cellulose degradation. The acetylated loofa sponge prepared under this condition was not decomposed by commercial cellulase and its structure was maintained for more than 720 h during repeated-batch treatments with commercial cellulase. A flocculating yeast (Saccharomyces cerevisiae IR-2) and a fungus (Trichoderma reesei QM9414) were successfully immobilized in the acetylated loofa sponge. In each case, the percentage of immobilized cells was as high as that obtained using nonacetylated loofa sponge. Acetylation had no adverse effects on cell growth and immobilization of T. reesei QM9414, as well as on cell growth and ethanol production by S. cerevisiae IR-2. T. reesei QM9414 immobilized on an acetylated loofa sponge was successfully used for repeated-batch cellulase production from commercial cellulose powder. Although the acetylated loofa sponge showed a slight weight loss, it was not disintegrated by activated sludge. The results obtained in this study showed that acetylated loofa sponge is suitable as an immobilization carrier for bioprocesses involving cellulase.

  13. Preparation of Chitosan-Based Hemostatic Sponges by Supercritical Fluid Technology

    PubMed Central

    Song, Hu-Fan; Chen, Ai-Zheng; Wang, Shi-Bin; Kang, Yong-Qiang; Ye, Shi-Fu; Liu, Yuan-Gang; Wu, Wen-Guo

    2014-01-01

    Using ammonium bicarbonate (AB) particles as a porogen, chitosan (CS)-based hemostatic porous sponges were prepared in supercritical carbon dioxide due to its low viscosity, small surface tension, and good compatibility with organic solvent. Fourier transform infrared spectroscopy (FTIR) spectra demonstrated that the chemical compositions of CS and poly-(methyl vinyl ether-co-maleic anhydride) (PVM/MA) were not altered during the phase inversion process. The morphology and structure of the sponge after the supercritical fluid (SCF) process were observed by scanning electron microscopy (SEM). The resulting hemostatic sponges showed a relatively high porosity (about 80%) with a controllable pore size ranging from 0.1 to 200 μm. The concentration of PVM/MA had no significant influence on the porosity of the sponges. Comparative experiments on biological assessment and hemostatic effect between the resulting sponges and Avitene® were also carried out. With the incorporation of PVM/MA into the CS-based sponges, the water absorption rate of the sponges increased significantly, and the CS-PVM/MA sponges showed a similar water absorption rate (about 90%) to that of Avitene®. The results of the whole blood clotting experiment and animal experiment also demonstrated that the clotting ability of the CS-PVM/MA sponges was similar to that of Avitene®. All these results elementarily verified that the sponges prepared in this study were suitable for hemostasis and demonstrated the feasibility of using SCF-assisted phase inversion technology to produce hemostatic porous sponges. PMID:28788577

  14. Digital Alloy Absorber for Photodetectors

    NASA Technical Reports Server (NTRS)

    Hill, Cory J. (Inventor); Ting, David Z. (Inventor); Gunapala, Sarath D. (Inventor)

    2016-01-01

    In order to increase the spectral response range and improve the mobility of the photo-generated carriers (e.g. in an nBn photodetector), a digital alloy absorber may be employed by embedding one (or fraction thereof) to several monolayers of a semiconductor material (insert layers) periodically into a different host semiconductor material of the absorber layer. The semiconductor material of the insert layer and the host semiconductor materials may have lattice constants that are substantially mismatched. For example, this may performed by periodically embedding monolayers of InSb into an InAsSb host as the absorption region to extend the cutoff wavelength of InAsSb photodetectors, such as InAsSb based nBn devices. The described technique allows for simultaneous control of alloy composition and net strain, which are both key parameters for the photodetector operation.

  15. Acoustic Properties of Absorbent Asphalts

    NASA Astrophysics Data System (ADS)

    Trematerra, Amelia; Lombardi, Ilaria

    2017-08-01

    Road traffic is one of the greater cause of noise pollution in urban centers; a prolonged exposure to this source of noise disturbs populations subjected to it. In this paper is reported a study on the absorbent coefficients of asphalt. The acoustic measurements are carried out with a impedance tube (tube of Kundt). The sample are measured in three conditions: with dry material (traditional), “wet” asphalt and “dirty” asphalt.

  16. PT-symmetric laser absorber

    SciTech Connect

    Longhi, Stefano

    2010-09-15

    In a recent work, Y. D. Chong et al. [Phys. Rev. Lett. 105, 053901 (2010)] proposed the idea of a coherent perfect absorber (CPA) as the time-reversed counterpart of a laser, in which a purely incoming radiation pattern is completely absorbed by a lossy medium. The optical medium that realizes CPA is obtained by reversing the gain with absorption, and thus it generally differs from the lasing medium. Here it is shown that a laser with an optical medium that satisfies the parity-time (PT) symmetry condition {epsilon}(-r)={epsilon}*(r) for the dielectric constant behaves simultaneously as a laser oscillator (i.e., it canmore » emit outgoing coherent waves) and as a CPA (i.e., it can fully absorb incoming coherent waves with appropriate amplitudes and phases). Such a device can thus be referred to as a PT-symmetric CPA laser. The general amplification or absorption features of the PT CPA laser below lasing threshold driven by two fields are determined.« less

  17. Energy-Absorbing, Lightweight Wheels

    NASA Technical Reports Server (NTRS)

    Waydo, Peter

    2003-01-01

    Improved energy-absorbing wheels are under development for use on special-purpose vehicles that must traverse rough terrain under conditions (e.g., extreme cold) in which rubber pneumatic tires would fail. The designs of these wheels differ from those of prior non-pneumatic energy-absorbing wheels in ways that result in lighter weights and more effective reduction of stresses generated by ground/wheel contact forces. These wheels could be made of metals and/or composite materials to withstand the expected extreme operating conditions. As shown in the figure, a wheel according to this concept would include an isogrid tire connected to a hub via spring rods. The isogrid tire would be a stiff, lightweight structure typically made of aluminum. The isogrid aspect of the structure would both impart stiffness and act as a traction surface. The hub would be a thin-walled body of revolution having a simple or compound conical or other shape chosen for structural efficiency. The spring rods would absorb energy and partially isolate the hub and the supported vehicle from impact loads. The general spring-rod configuration shown in the figure was chosen because it would distribute contact and impact loads nearly evenly around the periphery of the hub, thereby helping to protect the hub against damage that would otherwise be caused by large loads concentrated onto small portions of the hub.

  18. Retention of 125I-labeled recombinant human bone morphogenetic protein-2 by biphasic calcium phosphate or a composite sponge in a rabbit posterolateral spine arthrodesis model.

    PubMed

    Louis-Ugbo, John; Kim, Hak-Sun; Boden, Scott D; Mayr, Matthew T; Li, Ronald C; Seeherman, Howard; D'Augusta, Darren; Blake, Cara; Jiao, Aiping; Peckham, Steve

    2002-09-01

    The purpose of this study was to characterize the retention kinetics of recombinant human bone morphogenetic protein-2 (rhBMP-2) applied to two calcium-based delivery matrices. Biphasic calcium phosphate (BCP) and a composite containing BCP in an absorbable collagen sponge (BCP/ACS) were evaluated using a spinal fusion model in rabbits. rhBMP-2 labeled with radioactive iodine (125I) was used as a tracer to assess in vivo retention of rhBMP-2 in the presence of these materials (nine animals per material studied). Over a 36 day study period, animals were assessed for the following: percent administered dose retained at the implant site as measured by scintigraphic imaging (counting) with a gamma camera (all animals), radiography of the implant site (all animals), radioactivity in blood and plasma (all animals), and radioactivity in the urine and feces (three animals for each material). Radioactivity data were corrected for the decay of 125I and the attenuation between the implant in vivo and the gamma camera. Differences observed between the two materials for the area under the retention vs. time profile (AUC; 988%*day for BCP vs. 1070%*day for BCP/ACS, p = 0.57) and the mean residence time (MRT; 10.2 days for BCP vs. 7.6 days for BCP/ACS, p = 0.06) were not statistically significant. Initial retention/incorporation of rhBMP-2 was slightly higher for rhBMP-2/BCP/ACS than for rhBMP-2/BCP (96.8% vs. 86.0%, p < 0.05). Animals receiving rhBMP-2/BCP showed a longer terminal retention half-life (t1/2) than did those receiving rhBMP-2/BCP/ACS (7.5 vs. 4.5 days, p < 0.05). The urinary radioactivity recovery data supported the data obtained by scintigraphy. Over the 36 day collection period, essentially complete recovery of radioactivity (dose) in urine was observed for rhBMP-2/BCP and rhBMP-2/BCP/ACS and the majority of the radioactivity (approximately 95%) was soluble in trichloroacetic acid, suggesting extensive catabolism of rhBMP-2 before renal excretion. Fecal recovery

  19. Micromechanical testing of individual collagen fibrils.

    PubMed

    van der Rijt, Joost A J; van der Werf, Kees O; Bennink, Martin L; Dijkstra, Pieter J; Feijen, Jan

    2006-09-15

    A novel method based on AFM was used to attach individual collagen fibrils between a glass surface and the AFM tip, to allow force spectroscopy studies of these. The fibrils were deposited on glass substrates that are partly coated with Teflon AF. A modified AFM tip was used to accurately deposit epoxy glue droplets on either end of the collagen fibril that cross the glass-Teflon AF interface, as to such attach it with one end to the glass and the other end to the AFM tip. Single collagen fibrils have been mechanically tested in ambient conditions and were found to behave reversibly up to stresses of 90 MPa. Within this regime a Young's modulus of 2-7 GPa was obtained. In aqueous media, the collagen fibrils could be tested reversibly up to about 15 MPa, revealing Young's moduli ranging from 0.2 to at most 0.8 GPa.

  20. Collagen Accumulation in Osteosarcoma Cells lacking GLT25D1 Collagen Galactosyltransferase.

    PubMed

    Baumann, Stephan; Hennet, Thierry

    2016-08-26

    Collagen is post-translationally modified by prolyl and lysyl hydroxylation and subsequently by glycosylation of hydroxylysine. Despite the widespread occurrence of the glycan structure Glc(α1-2)Gal linked to hydroxylysine in animals, the functional significance of collagen glycosylation remains elusive. To address the role of glycosylation in collagen expression, folding, and secretion, we used the CRISPR/Cas9 system to inactivate the collagen galactosyltransferase GLT25D1 and GLT25D2 genes in osteosarcoma cells. Loss of GLT25D1 led to increased expression and intracellular accumulation of collagen type I, whereas loss of GLT25D2 had no effect on collagen secretion. Inactivation of the GLT25D1 gene resulted in a compensatory induction of GLT25D2 expression. Loss of GLT25D1 decreased collagen glycosylation by up to 60% but did not alter collagen folding and thermal stability. Whereas cells harboring individually inactivated GLT25D1 and GLT25D2 genes could be recovered and maintained in culture, cell clones with simultaneously inactive GLT25D1 and GLT25D2 genes could be not grown and studied, suggesting that a complete loss of collagen glycosylation impairs osteosarcoma cell proliferation and viability. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Collagen extraction from mussel byssus: a new marine collagen source with physicochemical properties of industrial interest.

    PubMed

    Rodríguez, F; Morán, L; González, G; Troncoso, E; Zúñiga, R N

    2017-04-01

    Mussel byssus is a by-product of mussel production and is a potential source of collagen. The goal of this study was to extract collagen from the byssus of Chilean mussel using an enzymatic method and characterize it. A pepsin-aided extraction method was employed where first an enzymatic hydrolysis at two pepsin/substrate ratios (1:50 or 4:50) and times (4 or 24 h) was done. Extraction was conducted at 80 °C for 24 h, in a 0.5 N acetic acid solution. All samples were analyzed for collagen content, amino acid profile, turbidity, viscosity, solubility, denaturation temperature and surface tension. Hydrolysis time had significant effect on collagen content, hydroxyproline content and extraction yield. Hydrolysis with a pepsin/byssus ratio of 4:50 for 24 h gave the better extraction performance with values of 69 mg/g protein, 1.8 mg/g protein and 30%, for collagen content, hydroxyproline content and extraction yield, respectively. No differences were found for the viscosity and surface tension of collagen dispersions, suggesting that the enzymatic hydrolysis did not affect the integrity of the collagen molecule. Denaturation temperature of freeze-dried byssus collagen presented a high value (83-91 °C), making this kind of collagen a very interesting material for encapsulation of bioactive molecules and for biomedical applications.

  2. Harnessing the Versatility of Bacterial Collagen to Improve the Chondrogenic Potential of Porous Collagen Scaffolds

    PubMed Central

    Parmar, Paresh A.; St-Pierre, Jean-Philippe; Chow, Lesley W.; Puetzer, Jennifer L.; Stoichevska, Violet; Peng, Yong Y.; Werkmeister, Jerome A.; Ramshaw, John A. M.; Stevens, Molly M.

    2017-01-01

    Collagen I foams are used in the clinic as scaffolds to promote articular cartilage repair as they provide a bioactive environment for cells with chondrogenic potential. However, collagen I as a base material does not allow for precise control over bioactivity. Alternatively, recombinant bacterial collagens can be used as “blank slate” collagen molecules to offer a versatile platform for incorporation of selected bioactive sequences and fabrication into 3D scaffolds. Here, we show the potential of Streptococcal collagen-like 2 (Scl2) protein foams modified with peptides designed to specifically and noncovalently bind hyaluronic acid and chondroitin sulfate to improve chondrogenesis of human mesenchymal stem cells (hMSCs) compared to collagen I foams. Specific compositions of functionalized Scl2 foams lead to improved chondrogenesis compared to both nonfunctionalized Scl2 and collagen I foams, as indicated by gene expression, extracellular matrix accumulation, and compression moduli. hMSCs cultured in functionalized Scl2 foams exhibit decreased collagens I and X gene and protein expression, suggesting an advantage over collagen I foams in promoting a chondrocytic phenotype. These highly modular foams can be further modified to improve specific aspects chondrogenesis. As such, these scaffolds also have the potential to be tailored for other regenerative medicine applications. PMID:27219220

  3. Collagen Accumulation in Osteosarcoma Cells lacking GLT25D1 Collagen Galactosyltransferase*

    PubMed Central

    Baumann, Stephan

    2016-01-01

    Collagen is post-translationally modified by prolyl and lysyl hydroxylation and subsequently by glycosylation of hydroxylysine. Despite the widespread occurrence of the glycan structure Glc(α1–2)Gal linked to hydroxylysine in animals, the functional significance of collagen glycosylation remains elusive. To address the role of glycosylation in collagen expression, folding, and secretion, we used the CRISPR/Cas9 system to inactivate the collagen galactosyltransferase GLT25D1 and GLT25D2 genes in osteosarcoma cells. Loss of GLT25D1 led to increased expression and intracellular accumulation of collagen type I, whereas loss of GLT25D2 had no effect on collagen secretion. Inactivation of the GLT25D1 gene resulted in a compensatory induction of GLT25D2 expression. Loss of GLT25D1 decreased collagen glycosylation by up to 60% but did not alter collagen folding and thermal stability. Whereas cells harboring individually inactivated GLT25D1 and GLT25D2 genes could be recovered and maintained in culture, cell clones with simultaneously inactive GLT25D1 and GLT25D2 genes could be not grown and studied, suggesting that a complete loss of collagen glycosylation impairs osteosarcoma cell proliferation and viability. PMID:27402836

  4. Techniques for Type I Collagen Organization

    NASA Astrophysics Data System (ADS)

    Anderson-Jackson, LaTecia Diamond

    Tissue Engineering is a process in which cells, engineering, and material methods are used in amalgamation to improve biological functions. The purpose of tissue engineering is to develop alternative solutions to treat or cure tissues and organs that have been severely altered or damaged by diseases, congenital defects, trauma, or cancer. One of the most common and most promising biological materials for tissue engineering to develop scaffolds is Type I collagen. A major challenge in biomedical research is aligning Type I collagen to mimic biological structures, such as ligaments, tendons, bones, and other hierarchal aligned structures within the human body. The intent of this research is to examine possible techniques for organizing Type I collagen and to assess which of the techniques is effective for potential biological applications. The techniques used in this research to organize collagen are soft lithography with solution-assisted sonication embossing, directional freezing, and direct poling. The final concentration used for both soft lithography with solution-assisted sonication embossing and direct poling was 1 mg/ml, whereas for directional freezing the final concentration varied between 4mg/ml, 2mg/ml, and 1 mg/ml. These techniques were characterized using the Atomic Force Microscope (AFM) and Helium Ion Microscope (HIM). In this study, we have found that out of the three techniques, the soft lithography and directional freezing techniques have been successful in organizing collagen in a particular pattern, but not alignment. We concluded alignment may be dependent on the pH of collagen and the amount of acetic acid used in collagen solution. However, experiments are still being conducted to optimize all three techniques to align collagen in a unidirectional arrangement.

  5. A randomized controlled trial on the efficacy and safety of a food ingredient, collagen hydrolysate, for improving joint comfort.

    PubMed

    Benito-Ruiz, P; Camacho-Zambrano, M M; Carrillo-Arcentales, J N; Mestanza-Peralta, M A; Vallejo-Flores, C A; Vargas-López, S V; Villacís-Tamayo, R A; Zurita-Gavilanes, L A

    2009-01-01

    Current options to promote joint comfort are limited to medicines that can reduce pain but can also have adverse effects. Collagen, a major component of joint cartilage, is found in the diet, particularly in meat. Its hydrolysed form, collagen hydrolysate (CH), is well absorbed. CH may stimulate the joint matrix cells to synthesize collagen, so helping to maintain the structure of the joint and potentially to aid joint comfort. In a randomized, double-blind, controlled multicentre trial, 250 subjects with primary osteoarthritis of the knee were given 10 g CH daily for 6 months. There was a significant improvement in knee joint comfort as assessed by visual analogue scales to assess pain and the Womac pain subscale. Subjects with the greatest joint deterioration, and with least intake of meat protein in their habitual diets, benefited most. CH is safe and effective and warrants further consideration as a food ingredient.

  6. On the run: free-living mushroom corals avoiding interaction with sponges

    NASA Astrophysics Data System (ADS)

    Hoeksema, B. W.; de Voogd, N. J.

    2012-06-01

    Individuals of the free-living mushroom coral Heliofungia fralinae moved away when placed in contact with fragments of the toxic haplosclerid sponge Callyspongia (Euplacella) biru. This reaction was not evoked by three other sponge species. The experiment demonstrated that mobility of mushroom corals helps them to flee from organisms that secrete secondary metabolites in competition for space.

  7. Effects of Chitin and Sepia Ink Hybrid Hemostatic Sponge on the Blood Parameters of Mice

    PubMed Central

    Zhang, Wei; Sun, Yu-Lin; Chen, Dao-Hai

    2014-01-01

    Chitin and sepia ink hybrid hemostatic sponge (CTSH sponge), a new biomedical material, was extensively studied for its beneficial biological properties of hemostasis and stimulation of healing. However, studies examining the safety of CTSH sponge in the blood system are lacking. This experiment aimed to examine whether CTSH sponge has negative effect on blood systems of mice, which were treated with a dosage of CTSH sponge (135 mg/kg) through a laparotomy. CTSH sponge was implanted into the abdominal subcutaneous and a laparotomy was used for blood sampling from abdominal aortic. Several kinds of blood parameters were detected at different time points, which were reflected by coagulation parameters including thrombin time (TT), prothrombin time (PT), activated partial thromboplatin time (APTT), fibrinogen (FIB) and platelet factor 4 (PF4); anticoagulation parameter including antithrombin III (AT-III); fibrinolytic parameters including plasminogen (PLG), fibrin degradation product (FDP) and D-dimer; hemorheology parameters including blood viscosity (BV) and plasma viscosity (PV). Results showed that CTSH sponge has no significant effect on the blood parameters of mice. The data suggested that CTSH sponge can be applied in the field of biomedical materials and has potential possibility to be developed into clinical drugs of hemostatic agents. PMID:24727395

  8. Sponge and skin excision sampling for recovery of Salmonella and Campylobacter from defeathered broiler carcasses

    USDA-ARS?s Scientific Manuscript database

    Introduction: Salmonella and Campylobacter contamination of broiler carcass skin increases during feather removal. There are several methods for sampling carcasses including sponging or swabbing of skin surface and skin excision. It is unclear whether sponge sampling is adequate to remove bacteri...

  9. Development of a multilocus-based approach for sponge (phylum Porifera) identification: refinement and limitations.

    PubMed

    Yang, Qi; Franco, Christopher M M; Sorokin, Shirley J; Zhang, Wei

    2017-02-02

    For sponges (phylum Porifera), there is no reliable molecular protocol available for species identification. To address this gap, we developed a multilocus-based Sponge Identification Protocol (SIP) validated by a sample of 37 sponge species belonging to 10 orders from South Australia. The universal barcode COI mtDNA, 28S rRNA gene (D3-D5), and the nuclear ITS1-5.8S-ITS2 region were evaluated for their suitability and capacity for sponge identification. The highest Bit Score was applied to infer the identity. The reliability of SIP was validated by phylogenetic analysis. The 28S rRNA gene and COI mtDNA performed better than the ITS region in classifying sponges at various taxonomic levels. A major limitation is that the databases are not well populated and possess low diversity, making it difficult to conduct the molecular identification protocol. The identification is also impacted by the accuracy of the morphological classification of the sponges whose sequences have been submitted to the database. Re-examination of the morphological identification further demonstrated and improved the reliability of sponge identification by SIP. Integrated with morphological identification, the multilocus-based SIP offers an improved protocol for more reliable and effective sponge identification, by coupling the accuracy of different DNA markers.

  10. Sponge and skin excision sampling for recovery of Salmonella and Campylobacter from defeathered broiler carcasses

    USDA-ARS?s Scientific Manuscript database

    Introduction: Salmonella and Campylobacter contamination of broiler carcass skin increases during feather removal. There are several methods for sampling carcasses including sponging or swabbing of skin surface and skin excision. It is unclear whether sponge sampling is adequate to remove bacteria f...

  11. 50 CFR 17.48 - Special rules-common sponges and other forms. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 2 2010-10-01 2010-10-01 false Special rules-common sponges and other forms. [Reserved] 17.48 Section 17.48 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Threatened Wildlife § 17.48 Special rules—common sponges and other forms. [Reserved] ...

  12. Putative cross-kingdom horizontal gene transfer in sponge (Porifera) mitochondria.

    PubMed

    Rot, Chagai; Goldfarb, Itay; Ilan, Micha; Huchon, Dorothée

    2006-09-14

    The mitochondrial genome of Metazoa is usually a compact molecule without introns. Exceptions to this rule have been reported only in corals and sea anemones (Cnidaria), in which group I introns have been discovered in the cox1 and nad5 genes. Here we show several lines of evidence demonstrating that introns can also be found in the mitochondria of sponges (Porifera). A 2,349 bp fragment of the mitochondrial cox1 gene was sequenced from the sponge Tetilla sp. (Spirophorida). This fragment suggests the presence of a 1143 bp intron. Similar to all the cnidarian mitochondrial introns, the putative intron has group I intron characteristics. The intron is present in the cox1 gene and encodes a putative homing endonuclease. In order to establish the distribution of this intron in sponges, the cox1 gene was sequenced from several representatives of the demosponge diversity. The intron was found only in the sponge order Spirophorida. A phylogenetic analysis of the COI protein sequence and of the intron open reading frame suggests that the intron may have been transmitted horizontally from a fungus donor. Little is known about sponge-associated fungi, although in the last few years the latter have been frequently isolated from sponges. We suggest that the horizontal gene transfer of a mitochondrial intron was facilitated by a symbiotic relationship between fungus and sponge. Ecological relationships are known to have implications at the genomic level. Here, an ecological relationship between sponge and fungus is suggested based on the genomic analysis.

  13. Development of a multilocus-based approach for sponge (phylum Porifera) identification: refinement and limitations

    PubMed Central

    Yang, Qi; Franco, Christopher M. M.; Sorokin, Shirley J.; Zhang, Wei

    2017-01-01

    For sponges (phylum Porifera), there is no reliable molecular protocol available for species identification. To address this gap, we developed a multilocus-based Sponge Identification Protocol (SIP) validated by a sample of 37 sponge species belonging to 10 orders from South Australia. The universal barcode COI mtDNA, 28S rRNA gene (D3–D5), and the nuclear ITS1-5.8S-ITS2 region were evaluated for their suitability and capacity for sponge identification. The highest Bit Score was applied to infer the identity. The reliability of SIP was validated by phylogenetic analysis. The 28S rRNA gene and COI mtDNA performed better than the ITS region in classifying sponges at various taxonomic levels. A major limitation is that the databases are not well populated and possess low diversity, making it difficult to conduct the molecular identification protocol. The identification is also impacted by the accuracy of the morphological classification of the sponges whose sequences have been submitted to the database. Re-examination of the morphological identification further demonstrated and improved the reliability of sponge identification by SIP. Integrated with morphological identification, the multilocus-based SIP offers an improved protocol for more reliable and effective sponge identification, by coupling the accuracy of different DNA markers. PMID:28150727

  14. Marine sponge-associated bacteria as a potential source for polyhydroxyalkanoates.

    PubMed

    Sathiyanarayanan, Ganesan; Saibaba, Ganesan; Kiran, George Seghal; Yang, Yung-Hun; Selvin, Joseph

    2017-05-01

    Marine sponges are filter feeding porous animals and usually harbor a remarkable array of microorganisms in their mesohyl tissues as transient and resident endosymbionts. The marine sponge-microbial interactions are highly complex and, in some cases, the relationships are thought to be truly symbiotic or mutualistic rather than temporary associations resulting from sponge filter-feeding activity. The marine sponge-associated bacteria are fascinating source for various biomolecules that are of potential interest to several biotechnological industries. In recent times, a particular attention has been devoted to bacterial biopolymer (polyesters) such as intracellular polyhydroxyalkanoates (PHAs) produced by sponge-associated bacteria. Bacterial PHAs act as an internal reserve for carbon and energy and also are a tremendous alternative for fossil fuel-based polymers mainly due to their eco-friendliness. In addition, PHAs are produced when the microorganisms are under stressful conditions and this biopolymer synthesis might be exhibited as one of the survival mechanisms of sponge-associated or endosymbiotic bacteria which exist in a highly competitive and stressful sponge-mesohyl microenvironment. In this review, we have emphasized the industrial prospects of marine bacteria for the commercial production of PHAs and special importance has been given to marine sponge-associated bacteria as a potential resource for PHAs.

  15. On the evolution of morphology of zirconium sponge during reduction and distillation

    SciTech Connect

    Kapoor, K.; Padmaprabu, C.; Nandi, D.

    2008-03-15

    High purity zirconium metal is produced by magnesio-thermic reduction of zirconium tetrachloride followed by vacuum distillation. The reduction process is carried out in a batch giving metal sponge and magnesium chloride in the reduced mass. The sponge is purified to using by vacuum distillation. The morphology of the sponge formed during the reduction and its influence on further processing has significant importance. In the present study, a detailed investigation involving evolution of the morphology of sponge particles and its implication during the vacuum distillation was carried out. The study of the microstructure was done using scanning electron microscopy and X-raymore » diffraction. It is observed that the nascent sponge formed is highly unstable which transforms to a needle-like morphology almost immediately, which further transforms to rounded and finally to a bulk shape. Faceting of the surface and needle-shape formation were observed in these particles, this is probably due to anisotropy in the surface energy. The morphology of the sponge formed during the reduction influences the distillation process. The fine needle-like shape sponge morphology leads to particle ejection, which is explained to be due to curvature effect. This is responsible for the formation of unwanted mass during distillation. XRD line broadening analysis indicates that the individual sponge particles are free from structural defects (dislocation) and are nearly single crystalline in nature.« less

  16. Draft Genome Sequence of Marine Sponge Symbiont Pseudoalteromonas luteoviolacea IPB1, Isolated from Hilo, Hawaii.

    PubMed

    Sakai-Kawada, Francis E; Yakym, Christopher J; Helmkampf, Martin; Hagiwara, Kehau; Ip, Courtney G; Antonio, Brandi J; Armstrong, Ellie; Ulloa, Wesley J; Awaya, Jonathan D

    2016-09-22

    We report here the 6.0-Mb draft genome assembly of Pseudoalteromonas luteoviolacea strain IPB1 that was isolated from the Hawaiian marine sponge Iotrochota protea Genome mining complemented with bioassay studies will elucidate secondary metabolite biosynthetic pathways and will help explain the ecological interaction between host sponge and microorganism. Copyright © 2016 Sakai-Kawada et al.

  17. Draft Genome Sequence of Marine Sponge Symbiont Pseudoalteromonas luteoviolacea IPB1, Isolated from Hilo, Hawaii

    PubMed Central

    Yakym, Christopher J.; Helmkampf, Martin; Hagiwara, Kehau; Ip, Courtney G.; Antonio, Brandi J.; Armstrong, Ellie; Ulloa, Wesley J.; Awaya, Jonathan D.

    2016-01-01

    We report here the 6.0-Mb draft genome assembly of Pseudoalteromonas luteoviolacea strain IPB1 that was isolated from the Hawaiian marine sponge Iotrochota protea. Genome mining complemented with bioassay studies will elucidate secondary metabolite biosynthetic pathways and will help explain the ecological interaction between host sponge and microorganism. PMID:27660784

  18. Chitosan-hyaluronan/nano chondroitin sulfate ternary composite sponges for medical use.

    PubMed

    Anisha, B S; Sankar, Deepthi; Mohandas, Annapoorna; Chennazhi, K P; Nair, Shantikumar V; Jayakumar, R

    2013-02-15

    In this work chitosan-hyaluronan composite sponge incorporated with chondroitin sulfate nanoparticle (nCS) was developed. The fabrication of hydrogel was based on simple ionic cross-linking using EDC, followed by lyophilization to obtain the composite sponge. nCS suspension was characterized using DLS and SEM and showed a size range of 100-150 nm. The composite sponges were characterized using SEM, FT-IR and TG-DTA. Porosity, swelling, biodegradation, blood clotting and platelet activation of the prepared sponges were also evaluated. Nanocomposites showed a porosity of 67% and showed enhanced swelling and blood clotting ability. Cytocompatibility and cell adhesion studies of the sponges were done using human dermal fibroblast (HDF) cells and the nanocomposite sponges showed more than 90% viability. Nanocomposite sponges also showed enhanced proliferation of HDF cells within two days of study. These results indicated that this nanocomposite sponges would be a potential candidate for wound dressing. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Jellyfish collagen scaffolds for cartilage tissue engineering.

    PubMed

    Hoyer, Birgit; Bernhardt, Anne; Lode, Anja; Heinemann, Sascha; Sewing, Judith; Klinger, Matthias; Notbohm, Holger; Gelinsky, Michael

    2014-02-01

    Porous scaffolds were engineered from refibrillized collagen of the jellyfish Rhopilema esculentum for potential application in cartilage regeneration. The influence of collagen concentration, salinity and temperature on fibril formation was evaluated by turbidity measurements and quantification of fibrillized collagen. The formation of collagen fibrils with a typical banding pattern was confirmed by atomic force microscopy and transmission electron microscopy analysis. Porous scaffolds from jellyfish collagen, refibrillized under optimized conditions, were fabricated by freeze-drying and subsequent chemical cross-linking. Scaffolds possessed an open porosity of 98.2%. The samples were stable under cyclic compression and displayed an elastic behavior. Cytotoxicity tests with human mesenchymal stem cells (hMSCs) did not reveal any cytotoxic effects of the material. Chondrogenic markers SOX9, collagen II and aggrecan were upregulated in direct cultures of hMSCs upon chondrogenic stimulation. The formation of typical extracellular matrix components was further confirmed by quantification of sulfated glycosaminoglycans. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  20. Marine Origin Collagens and Its Potential Applications

    PubMed Central

    Silva, Tiago H.; Moreira-Silva, Joana; Marques, Ana L. P.; Domingues, Alberta; Bayon, Yves; Reis, Rui L.

    2014-01-01

    Collagens are the most abundant high molecular weight proteins in both invertebrate and vertebrate organisms, including mammals, and possess mainly a structural role, existing different types according with their specific organization in distinct tissues. From this, they have been elected as one of the key biological materials in tissue regeneration approaches. Also, industry is constantly searching for new natural sources of collagen and upgraded methodologies for their production. The most common sources are from bovine and porcine origin, but other ways are making their route, such as recombinant production, but also extraction from marine organisms like fish. Different organisms have been proposed and explored for collagen extraction, allowing the sustainable production of different types of collagens, with properties depending on the kind of organism (and their natural environment) and extraction methodology. Such variety of collagen properties has been further investigated in different ways to render a wide range of applications. The present review aims to shed some light on the contribution of marine collagens for the scientific and technological development of this sector, stressing the opportunities and challenges that they are and most probably will be facing to assume a role as an alternative source for industrial exploitation. PMID:25490254

  1. Acemannan sponges stimulate alveolar bone, cementum and periodontal ligament regeneration in a canine class II furcation defect model.

    PubMed

    Chantarawaratit, P; Sangvanich, P; Banlunara, W; Soontornvipart, K; Thunyakitpisal, P

    2014-04-01

    Periodontal disease is a common infectious disease, found worldwide, causing the destruction of the periodontium. The periodontium is a complex structure composed of both soft and hard tissues, thus an agent applied to regenerate the periodontium must be able to stimulate periodontal ligament, cementum and alveolar bone regeneration. Recent studies demonstrated that acemannan, a polysaccharide extracted from Aloe vera gel, stimulated both soft and hard tissue healing. This study investigated effect of acemannan as a bioactive molecule and scaffold for periodontal tissue regeneration. Primary human periodontal ligament cells were treated with acemannan in vitro. New DNA synthesis, expression of growth/differentiation factor 5 and runt-related transcription factor 2, expression of vascular endothelial growth factor, bone morphogenetic protein-2 and type I collagen, alkaline phosphatase activity, and mineralized nodule formation were determined using [(3)H]-thymidine incorporation, reverse transcription-polymerase chain reaction, enzyme-linked immunoabsorbent assay, biochemical assay and alizarin red staining, respectively. In our in vivo study, premolar class II furcation defects were made in four mongrel dogs. Acemannan sponges were applied into the defects. Untreated defects were used as a negative control group. The amount of new bone, cementum and periodontal ligament formation were evaluated 30 and 60 d after the operation. Acemannan significantly increased periodontal ligament cell proliferation, upregulation of growth/differentiation factor 5, runt-related transcription factor 2, vascular endothelial growth factor, bone morphogenetic protein 2, type I collagen and alkaline phosphatase activity, and mineral deposition as compared with the untreated control group in vitro. Moreover, acemannan significantly accelerated new alveolar bone, cementum and periodontal ligament formation in class II furcation defects. Our data suggest that acemannan could be a candidate

  2. Shock absorber operates over wide range

    NASA Technical Reports Server (NTRS)

    Creasy, W. K.; Jones, J. C.

    1965-01-01

    Piston-type hydraulic shock absorber, with a metered damping system, operates over a wide range of kinetic energy loading rates. It is used for absorbing shock and vibration on mounted machinery and heavy earth-moving equipment.

  3. Collagen as potential cell scaffolds for tissue engineering.

    PubMed

    Annuar, N; Spier, R E

    2004-05-01

    Selections of collagen available commercially were tested for their biocompatibility as scaffold to promote cell growth in vitro via simple collagen fast test and cultivation of mammalian cells on the selected type of collagen. It was found that collagen type C9791 promotes the highest degree of aggregation as well as cells growth. This preliminary study also indicated potential use of collagen as scaffold in engineered tissue.

  4. Histological observation of a gelatin sponge transplant loaded with bone marrow-derived mesenchymal stem cells combined with platelet-rich plasma in repairing an annulus defect

    PubMed Central

    Xu, Xiang; Hu, Jianzhong; Lu, Hongbin

    2017-01-01

    Objective To research the histological characteristics of a gelatin sponge transplant loaded with goat BMSCs (bone marrow-derived mesenchymal stem cells) combined with PRP (platelet-rich plasma) in repairing an annulus defect. Method BMSCs were separated from the iliac crest of goats, sub-cultured and identified after the third generation. Then, PRP was obtained using blood from the jugular vein of goats via two degrees of centrifugation. In the animal experiments, the goats were divided into the following three groups: a sham group, an injury group and a therapeutic group. In the sham group, we decompressed the lamina and exposed the annulus fibrosus. In the injury group, we exposed the annulus fibrosus after decompression of the lamina and created a 1 × 1 cm defect in the annulus using surgical instruments. In the therapeutic group, after decompression of the lamina, we exposed the annulus, created a 1 × 1 cm defect using surgical instruments, and placed a gelatin sponge combined with BMSCs and PRP into the defect for a combined method of repair. Three, six and twelve weeks after the surgery, the previously damaged or undamaged annulus tissue was removed from the three groups. Then, the above tissue was assayed using HE (hematoxylin-eosin) staining, Masson trichrome staining, AB-PAS (Alcian blue-periodic acid Schiff) staining, and type II collagen staining and observed by microscopy. Results From the HE staining, we observed that the number of repair cells gradually increased. Compared to the injury group, the cell density and gross morphology of cells in the therapeutic group were closer to those of the sham group. As observed by Masson trichrome gelatin staining, many of the fibroblast cells or tissues were under repair, and as time progressed, the number of fibroblast cells and amount of tissue gradually increased. The results of the AB-PAS staining suggest that chondrocytes participated in the repair of the annulus. The level of type II collagen gradually

  5. Facile synthesis of flexible macroporous polypropylene sponges for separation of oil and water

    PubMed Central

    Wang, Guowei; Uyama, Hiroshi

    2016-01-01

    Oil spill disasters always occur accidentally, accompanied by the release of plenty of crude oil that could spread quickly over a wide area, creating enormous damage to the fragile marine ecological system. Therefore, the facile large-scale synthesis of hydrophobic three-dimensional (3-D) porous sorbents from low cost raw materials is in urgent demand. In this study, we report the facile template-free synthesis of polypropylene (PP) sponge by using a thermally-induced phase separation (TIPS) technique. The obtained sponge showed macroporous structure, excellent mechanical property, high hydrophobicity, and superoleophilicity. Oil could be separated from an oil/water mixture by simple immersing the sponge into the mixture and subsequent squeezing the sponge. All of these features make this sponge the most promising oil sorbent that will replace commercial non-woven PP fabrics. PMID:26880297

  6. 2'-phosphodiesterase and 2',5'-oligoadenylate synthetase activities in the lowest metazoans, sponge [porifera].

    PubMed

    Saby, Emilie; Poulsen, Jesper Buchhave; Justesen, Just; Kelve, Merike; Uriz, Maria Jesus

    2009-01-01

    Sponges [porifera], the most ancient metazoans, contain modules related to the vertebrate immune system, including the 2',5'-oligoadenylate synthetase (OAS). The components of the antiviral 2',5'-oligoadenylate (2-5A) system (OAS, 2'-Phosphodiesterase (2'-PDE) and RNAse L) of vertebrates have not all been identified in sponges. Here, we demonstrate for the first time that in addition to the OAS activity, sponges possess a 2'-PDE activity, which highlights the probable existence of a premature 2-5A system. Indeed, Suberites domuncula and Crella elegans exhibited this 2-5A degrading activity. Upon this finding, two out of three elements forming the 2-5A system have been found in sponges, only a endoribonuclease, RNAse L or similar, has to be found. We suspect the existence of a complex immune system in sponges, besides the self/non-self recognition system and the use of phagocytosis and secondary metabolites against pathogens.

  7. The effects of coastal development on sponge abundance, diversity, and community composition on Jamaican coral reefs.

    PubMed

    Stubler, Amber D; Duckworth, Alan R; Peterson, Bradley J

    2015-07-15

    Over the past decade, development along the northern coast of Jamaica has accelerated, resulting in elevated levels of sedimentation on adjacent reefs. To understand the effects of this development on sponge community dynamics, we conducted surveys at three locations with varying degrees of adjacent coastal development to quantify species richness, abundance and diversity at two depths (8-10 m and 15-18 m). Sediment accumulation rate, total suspended solids and other water quality parameters were also quantified. The sponge community at the location with the least coastal development and anthropogenic influence was often significantly different from the other two locations, and exhibited higher sponge abundance, richness, and diversity. Sponge community composition and size distribution were statistically different among locations. This study provides correlative evidence that coastal development affects aspects of sponge community ecology, although the precise mechanisms are still unclear. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Molecular evidence for a uniform microbial community in sponges from different oceans.

    PubMed

    Hentschel, Ute; Hopke, Jörn; Horn, Matthias; Friedrich, Anja B; Wagner, Michael; Hacker, Jörg; Moore, Bradley S

    2002-09-01

    Sponges (class Porifera) are evolutionarily ancient metazoans that populate the tropical oceans in great abundances but also occur in temperate regions and even in freshwater. Sponges contain large numbers of bacteria that are embedded within the animal matrix. The phylogeny of these bacteria and the evolutionary age of the interaction are virtually unknown. In order to provide insights into the species richness of the microbial community of sponges, we performed a comprehensive diversity survey based on 190 sponge-derived 16S ribosomal DNA (rDNA) sequences. The sponges Aplysina aerophoba and Theonella swinhoei were chosen for construction of the bacterial 16S rDNA library because they are taxonomically distantly related and they populate nonoverlapping geographic regions. In both sponges, a uniform microbial community was discovered whose phylogenetic signature is distinctly different from that of marine plankton or marine sediments. Altogether 14 monophyletic, sponge-specific sequence clusters were identified that belong to at least seven different bacterial divisions. By definition, the sequences of each cluster are more closely related to each other than to a sequence from nonsponge sources. These monophyletic clusters comprise 70% of all publicly available sponge-derived 16S rDNA sequences, reflecting the generality of the observed phenomenon. This shared microbial fraction represents the smallest common denominator of the sponges investigated in this study. Bacteria that are exclusively found in certain host species or that occur only transiently would have been missed. A picture emerges where sponges can be viewed as highly concentrated reservoirs of so far uncultured and elusive marine microorganisms.

  9. Efforts to develop a cultured sponge cell line: revisiting an intractable problem.

    PubMed

    Grasela, James J; Pomponi, Shirley A; Rinkevich, Buki; Grima, Jennifer

    2012-01-01

    Residents of the marine environment, sponges (Porifera) have the ability to produce organic compounds known as secondary metabolites, which are not directly involved in the normal growth, development, or reproduction of an organism. Because of their sessile nature, the production of these bioactive compounds has been interpreted as a functional adaptation to serve in an important survival role as a means to counter various environmental stress factors such as predation, overgrowth by fouling organisms, or competition for limited space. Regardless of the reasons for this adaptation, a variety of isolated compounds have already proven to demonstrate remarkable anticancer, fungicidal, and antibiotic properties. A major obstacle to the isolation and production of novel compounds from sponges is the lack of a large, reliable source of sponge material. Sponge collection from the sea would be environmentally detrimental to the already stressed and sparse sponge populations. Sponge production in an aquaculture setting might appear to be an ideal alternative but would also be cost-ineffective and sponge growth is extremely slow. A third approach involves the development of a sponge cell culture system capable of producing the necessary cell numbers to harvest for research purposes as well as for the eventual commercial-scale production of promising bioactive compounds. Unfortunately, little progress has been made in this direction other than the establishment of temporary cultures containing aggregates and fragments of cells. One impediment toward successful sponge cell culture might be ascribed to a lack of published knowledge of failed methodologies, and thus, time and effort is wasted on continued reinvention of the same methods and procedures. Consequently, we have undertaken here to chart some of our unsuccessful research efforts, our methodology, and results to provide the sponge research community with knowledge to assist them to better avoid taking the same failed

  10. Effects of submarine power transmission cables on a glass sponge reef and associated megafaunal community.

    PubMed

    Dunham, A; Pegg, J R; Carolsfeld, W; Davies, S; Murfitt, I; Boutillier, J

    2015-06-01

    We examined the effects of submarine power transmission cable installation and operation on glass sponge reef condition and associated megafauna. Video and still imagery were collected using a Remotely Operated Vehicle twice a year for 4 years following cable installation. The effects of cables on glass sponges were assessed by comparing sponge cover along fixed transects and at marked index sites. Megafauna counts along transects were used to explore the effects on associated community. We found no evidence of cable movement across the sponge reef surface. Live sponge cover was found to be consistently lower along cable transects and at cable index sites compared to controls. Live sponge cover was the lowest (55 ± 1.1% decrease) at cable index sites 1.5 years after installation and recovered to 85 ± 30.6% of the original size over the following 2 years. Our data suggest 100% glass sponge mortality along the direct cable footprint and 15% mortality in the surrounding 1.5 m corridor 3.5 years after cable installation. Growth rate of a new glass sponge was 1 and 3 cm/year in first and second year, respectively, and appeared to be seasonal. We observed a diverse megafaunal community with representatives from 7 phyla and 14 classes. Total megafauna, spot prawn, and other Arthropoda abundances were slightly lower along cable transects although the effect of cable presence was not statistically significant. The following measures could be taken to reduce the amount of damage to glass sponge reefs and associated fauna: routing the cable around reefs, whenever possible, minimizing cable movement across the surface of the reef at installation and routine operation, and assessing potential damage to glass sponges prior to decommissioning. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  11. Long-term effects of bottom trawling on large sponges in the Gulf of Alaska

    NASA Astrophysics Data System (ADS)

    Malecha, Patrick; Heifetz, Jonathan

    2017-11-01

    Manipulative studies that characterize short-term effects of bottom trawls on seafloor habitats are numerous, but studies that examine long-term effects are rare. The long-term (13 years) effects of a single bottom trawl on large (>20 cm) erect sponges were investigated by revisiting the site of prior experimental trawling studies. In prior studies, large sponges were assessed immediately after trawling and 1 yr post-trawling. Thirteen years post-trawling, the average density of large sponges was 31.7% lower (range 1.5-53.0%) and the incidence of sponge damage (torn, necrotic, missing tissue, prone) was 58.8% higher within strip transects in trawled versus untrawled reference areas. For all sponge species combined, the mean density of large sponges was 3.19 individuals 100 m-2 in trawled areas and 4.67 individuals 100 m-2 in reference areas. The most abundant sponge species in both trawled and reference areas was Rhabdocalyptus dawsoni. Mean density of this species differed greatly between trawled (1.57 individuals 100 m-2) and reference areas (2.91 individuals 100 m-2). Thirteen years after trawling, the mean percentage of damaged sponges on strip transects was 15.3% in trawled areas and 6.3% in reference areas. The rate of damage in trawled areas was less than that observed both immediately after trawling and 1 year later. The persistence of damage (lower sponge densities and higher rates of injury in trawled areas) and the potential resultant changes to benthic communities where deepwater habitat-forming biota, such as large erect sponges, are present provide rationale for cautious management of the long term effects of bottom trawling.

  12. Porcelain enamel neutron absorbing material

    DOEpatents

    Iverson, D.C.

    1987-11-20

    A porcelain enamel composition as a neutron absorbing material can be prepared of a major proportion by weight of a cadmium compound and a minor proportion of compound of boron, lithium and silicon. These compounds in the form of a porcelain enamel coating or layer on several alloys has been found to be particularly effective in enhancing the nuclear safety of equipment for use in the processing and storage of fissile material. The composition of the porcelain enamel coating can be tailored to match the coefficient of thermal expansion of the equipment to be coated and excellent coating adhesion can be achieved. 2 figs.

  13. Porcelain enamel neutron absorbing material

    DOEpatents

    Iverson, Daniel C.

    1990-01-01

    A porcelain enamel composition as a neutron absorbing material can be prepared of a major proportion by weight of a cadmium compound and a minor proportion of compounds of boron, lithium and silicon. These compounds in the form of a porcelain enamel coating or layer on several alloys has been found to be particularly effective in enhancing the nuclear safety of equipment for use in the processing and storage of fissile material. The composition of the porcelain enamel coating can be tailored to match the coefficient of thermal expansion of the equipment to be coated and excellent coating adhesion can be achieved.

  14. Porcelain enamel neutron absorbing material

    DOEpatents

    Iverson, Daniel C.

    1990-02-06

    A porcelain enamel composition as a neutron absorbing material can be prepared of a major proportion by weight of a cadmium compound and a minor proportion of compounds of boron, lithium and silicon. These compounds in the form of a porcelain enamel coating or layer on several alloys has been found to be particularly effective in enhancing the nuclear safety of equipment for use in the processing and storage of fissile material. The composition of the porcelain enamel coating can be tailored to match the coefficient of thermal expansion of the equipment to be coated and excellent coating adhesion can be achieved.

  15. Potent Cytotoxic Peptides from the Australian Marine Sponge Pipestela candelabra

    PubMed Central

    Tran, Trong D.; Pham, Ngoc B.; Fechner, Gregory A.; Hooper, John N. A.; Quinn, Ronald J.

    2014-01-01

    Two consecutive prefractionated fractions of the Australian marine sponge extract, Pipestela candelabra, were identified to be selectively active on the human prostate cancer cells (PC3) compared to the human neonatal foreskin fibroblast non-cancer cells (NFF). Twelve secondary metabolites were isolated in which four compounds are new small peptides. Their structures were characterized by spectroscopic and chemical analysis. These compounds inhibited selectively the growth of prostate cancer cells with IC50 values in the picomolar to sub-micromolar range. Structure-activity relationship of these compounds is discussed. PMID:24901701

  16. A collagen-binding EGFR antibody fragment targeting tumors with a collagen-rich extracellular matrix

    PubMed Central

    Liang, Hui; Li, Xiaoran; Wang, Bin; Chen, Bing; Zhao, Yannan; Sun, Jie; Zhuang, Yan; Shi, Jiajia; Shen, He; Zhang, Zhijun; Dai, Jianwu

    2016-01-01

    Many tumors over-express collagen, which constitutes the physical scaffold of tumor microenvironment. Collagen has been considered to be a target for cancer therapy. The collagen-binding domain (CBD) is a short peptide, which could bind to collagen and achieve the sustained release of CBD-fused proteins in collagen scaffold. Here, a collagen-binding EGFR antibody fragment was designed and expressed for targeting the collagen-rich extracellular matrix in tumors. The antibody fragment (Fab) of cetuximab was fused with CBD (CBD-Fab) and expressed in Pichia pastoris. CBD-Fab maintained antigen binding and anti-tumor activity of cetuximab and obtained a collagen-binding ability in vitro. The results also showed CBD-Fab was mainly enriched in tumors and had longer retention time in tumors in A431 s.c. xenografts. Furthermore, CBD-Fab showed a similar therapeutic efficacy as cetuximab in A431 xenografts. Although CBD-Fab hasn’t showed better therapeutic effects than cetuximab, its smaller molecular and special target may be applicable as antibody–drug conjugates (ADC) or immunotoxins. PMID:26883295

  17. A collagen-binding EGFR antibody fragment targeting tumors with a collagen-rich extracellular matrix.

    PubMed

    Liang, Hui; Li, Xiaoran; Wang, Bin; Chen, Bing; Zhao, Yannan; Sun, Jie; Zhuang, Yan; Shi, Jiajia; Shen, He; Zhang, Zhijun; Dai, Jianwu

    2016-02-17

    Many tumors over-express collagen, which constitutes the physical scaffold of tumor microenvironment. Collagen has been considered to be a target for cancer therapy. The collagen-binding domain (CBD) is a short peptide, which could bind to collagen and achieve the sustained release of CBD-fused proteins in collagen scaffold. Here, a collagen-binding EGFR antibody fragment was designed and expressed for targeting the collagen-rich extracellular matrix in tumors. The antibody fragment (Fab) of cetuximab was fused with CBD (CBD-Fab) and expressed in Pichia pastoris. CBD-Fab maintained antigen binding and anti-tumor activity of cetuximab and obtained a collagen-binding ability in vitro. The results also showed CBD-Fab was mainly enriched in tumors and had longer retention time in tumors in A431 s.c. xenografts. Furthermore, CBD-Fab showed a similar therapeutic efficacy as cetuximab in A431 xenografts. Although CBD-Fab hasn't showed better therapeutic effects than cetuximab, its smaller molecular and special target may be applicable as antibody-drug conjugates (ADC) or immunotoxins.

  18. Imaging denatured collagen strands in vivo and ex vivo via photo-triggered hybridization of caged collagen mimetic peptides.

    PubMed

    Li, Yang; Foss, Catherine A; Pomper, Martin G; Yu, S Michael

    2014-01-31

    Collagen is a major structural component of the extracellular matrix that supports tissue formation and maintenance. Although collagen remodeling is an integral part of normal tissue renewal, excessive amount of remodeling activity is involved in tumors, arthritis, and many other pathological conditions. During collagen remodeling, the triple helical structure of collagen molecules is disrupted by proteases in the extracellular environment. In addition, collagens present in many histological tissue samples are partially denatured by the fixation and preservation processes. Therefore, these denatured collagen strands can serve as effective targets for biological imaging. We previously developed a caged collagen mimetic peptide (CMP) that can be photo-triggered to hybridize with denatured collagen strands by forming triple helical structure, which is unique to collagens. The overall goals of this procedure are i) to image denatured collagen strands resulting from normal remodeling activities in vivo, and ii) to visualize collagens in ex vivo tissue sections using the photo-triggered caged CMPs. To achieve effective hybridization and successful in vivo and ex vivo imaging, fluorescently labeled caged CMPs are either photo-activated immediately before intravenous injection, or are directly activated on tissue sections. Normal skeletal collagen remolding in nude mice and collagens in prefixed mouse cornea tissue sections are imaged in this procedure. The imaging method based on the CMP-collagen hybridization technology presented here could lead to deeper understanding of the tissue remodeling process, as well as allow development of new diagnostics for diseases associated with high collagen remodeling activity.

  19. Molecular assessment of collagen denaturation in decellularized tissues using a collagen hybridizing peptide.

    PubMed

    Hwang, Jeongmin; San, Boi Hoa; Turner, Neill J; White, Lisa J; Faulk, Denver M; Badylak, Stephen F; Li, Yang; Yu, S Michael

    2017-04-15

    Decellularized extracellular matrix (ECM) derived from tissues and organs are emerging as important scaffold materials for regenerative medicine. Many believe that preservation of the native ECM structure during decellularization is highly desirable. However, because effective techniques to assess the structural damage in ECM are lacking, the disruptive effects of a decellularization method and the impact of the associated structural damage upon the scaffold's regenerative capacity are often debated. Using a novel collagen hybridizing peptide (CHP) that specifically binds to unfolded collagen chains, we investigated the molecular denaturation of collagen in the ECM decellularized by four commonly used cell-removing detergents: sodium dodecyl sulfate (SDS), 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), sodium deoxycholate (SD), and Triton X-100. Staining of the detergent-treated porcine ligament and urinary bladder matrix with carboxyfluorescein-labeled CHP demonstrated that SDS and Triton X-100 denature the triple helical collagen molecule while CHAPS and SD do not, although second harmonic generation imaging and transmission electron microscopy (TEM) revealed that all four detergents disrupt collagen fibrils. Our findings from the CHP staining were further confirmed by the circular dichroism spectra of intact triple helical collagen molecules in CHAPS and SD solutions, and the TEM images of CHP-conjugated gold nanoparticles binding only to the SDS and Triton X-100 treated collagen fibrils. CHP is a powerful new tool for direct and reliable measurement of denatured collagen molecules in decellularized tissues. It is expected to have wide applications in the development and standardization of the tissue/organ decellularization technology. Preservation of the native ECM structure in decellularized tissues is highly desirable, since denaturation of ECM molecules (e.g., collagen) during decellularization can strongly influence the cellular response

  20. Molecular assessment of collagen denaturation in decellularized tissues using a collagen hybridizing peptide

    PubMed Central

    Hwang, Jeongmin; San, Boi Hoa; Turner, Neill J.; White, Lisa J.; Faulk, Denver M.; Badylak, Stephen F.; Li, Yang; Yu, S. Michael

    2017-01-01

    Decellularized extracellular matrix (ECM) derived from tissues and organs are emerging as important scaffold materials for regenerative medicine. Many believe that preservation of the native ECM structure during decellularization is highly desirable. However, because effective techniques to assess the structural damage in ECM are lacking, the disruptive effects of a decellularization method and the impact of the associated structural damage upon the scaffold’s regenerative capacity are often debated. Using a novel collagen hybridizing peptide (CHP) that specifically binds to unfolded collagen chains, we investigated the molecular denaturation of collagen in the ECM decellularized by four commonly used cellremoving detergents: sodium dodecyl sulfate (SDS), 3-[(3-cholamidopropyl)dimethylammonio]-1-propa nesulfonate (CHAPS), sodium deoxycholate (SD), and Triton X-100. Staining of the detergent-treated porcine ligament and urinary bladder matrix with carboxyfluorescein-labeled CHP demonstrated that SDS and Triton X-100 denature the triple helical collagen molecule while CHAPS and SD do not, although second harmonic generation imaging and transmission electron microscopy (TEM) revealed that all four detergents disrupt collagen fibrils. Our findings from the CHP staining were further confirmed by the circular dichroism spectra of intact triple helical collagen molecules in CHAPS and SD solutions, and the TEM images of CHP-conjugated gold nanoparticles binding only to the SDS and Triton X-100 treated collagen fibrils. CHP is a powerful new tool for direct and reliable measurement of denatured collagen molecules in decellularized tissues. It is expected to have wide applications in the development and standardization of the tissue/organ decellularization technology. Statement of Significance Preservation of the native ECM structure in decellularized tissues is highly desirable, since denaturation of ECM molecules (e.g., collagen) during decellularization can strongly

  1. Warfarin affects acute inflammatory response induced by subcutaneous polyvinyl sponge implantation in rats.

    PubMed

    Mirkov, Ivana; Popov Aleksandrov, Aleksandra; Demenesku, Jelena; Ninkov, Marina; Mileusnic, Dina; Kataranovski, Dragan; Kataranovski, Milena

    2017-09-01

    Warfarin (WF) is an anticoagulant which also affects physiological processes other than hemostasis. Our previous investigations showed the effect of WF which gained access to the organism via skin on resting peripheral blood granulocytes. Based on these data, the aim of the present study was to examine whether WF could modulate the inflammatory processes as well. To this aim the effect of WF on the inflammatory response induced by subcutaneous sponge implantation in rats was examined. Warfarin-soaked polyvinyl sponges (WF-sponges) were implanted subcutaneously and cell infiltration into sponges, the levels of nitric oxide (NO) and inflammatory cytokines tumor necrosis factor (TNF) and interleukin-6 (IL-6) production by sponge cells were measured as parameters of inflammation. T cell infiltration and cytokine interferon-γ (IFN-γ), interleukin-17 (IL-17) and interleukin-10 (IL-10) were measured at day 7 post implantation. Warfarin exerted both stimulatory and suppressive effects depending on the parameter examined. Flow cytometry of cells recovered from sponges showed higher numbers of granulocytes (HIS48 + cells) at days 1 and 3 post implantation and CD11b + cells at day 1 compared to control sponges. Cells from WF-sponges had an increased NO production (Griess reaction) at days 1 and 7. In contrast, lower levels of TNF (measured by ELISA) production by cells recovered from WF-soaked sponges were found in the early (day one) phase of reaction with unchanged levels at other time points. While IL-6 production by cells recovered from WF-soaked sponges was decreased at day 1, it was increased at day 7. Higher T cell numbers were noted in WF sponges at day 7 post implantation, and recovered cells produced more IFN-γ and IL-17, while IL-10 production remained unchanged. Warfarin affects some of the parameters of inflammatory reaction induced by subcutaneous polyvinyl sponge implantation. Differential (both stimulatory as well as inhibitory) effects of WF on

  2. Thai Silk Fibroin/Gelatin Sponges for the Dual Controlled Release of Curcumin and Docosahexaenoic Acid for Anticancer Treatment.

    PubMed

    Lerdchai, Kantarat; Kitsongsermthon, Jutarat; Ratanavaraporn, Juthamas; Kanokpanont, Sorada; Damrongsakkul, Siriporn

    2016-01-01

    In this study, curcumin and/or docosahexaenoic acid (DHA) were encapsulated in Thai silk fibroin/gelatin (SF/G) sponges, prepared at different blending ratios, aimed to be applied as a controlled release system for localized cancer therapy. The SF/G sponges were fabricated by freeze-drying and glutaraldehyde cross-linking techniques. Physicochemical properties of the SF/G sponges were characterized. Then, curcumin and/or DHA were loaded in the sponges by physical adsorption. The encapsulation efficiency and the in vitro release of curcumin and/or DHA from the sponges were evaluated. SF/G sponges could encapsulate curcumin and/or DHA at high encapsulation efficiency. The highly cross-linked and slowly degrading SF/G (50/50) sponge released curcumin and/or DHA at the slowest rate. The in vitro cytotoxicity of the sponges against noncancer cells (L929 mouse fibroblast) and anticancer of curcumin and/or DHA released from the sponges against cervical cancer cells (CaSki) were tested. All sponges were not toxic to L929 mouse fibroblast. The mixed curcumin–DHA at the ratio of 1:4 had the highest inhibiting effect on the growth of CaSki, comparing with the release of curcumin or DHA alone. SF/G sponges could be a potential carrier for dual release of curcumin and DHA for anticancer effect.

  3. Immunostimulatory effects of collagen from jellyfish in vivo.

    PubMed

    Morishige, Hitoshi; Sugahara, Takuya; Nishimoto, Sogo; Muranaka, Ayako; Ohno, Fumi; Shiraishi, Ryusuke; Doi, Mikiharu

    2011-10-01

    We focused on the biological activity of the collagen extracts obtained from the giant edible jellyfish, Nemopilema nomurai. Jellyfish collagen extracts stimulates the production of immunoglobulins (Igs) and cytokines by human hybridoma cells and human peripheral blood lymphocytes. Therefore, we examined the immunoregulatory function of jellyfish collagen extracts in mice. Intake of jellyfish collagen extracts facilitated the Ig production activity of lymphocytes from spleen and Peyer's patch. Furthermore, the levels of Igs in the serum clearly increased after the administration of jellyfish collagen extracts. Intake of bovine collagen from Achilles' tendon also activated lymphocytes activity in mice. The activity of total and antigen-specific Ig production in splenocytes from OVA-challenged mice was also enhanced by collagen intake. However, the total and OVA-specific IgE levels in the serum were not affected by the collagen intake. These results suggested that jellyfish collagen extracts stimulates an immune response in vivo, without inducing allergic complications.

  4. Effect of carboxymethylcellulose on fibril formation of collagen in vitro.

    PubMed

    Ding, Cuicui; Shi, Ronghui; Zheng, Zhigong; Zhang, Min

    2018-01-01

    The effect of carboxymethylcellulose (CMC) on the fibril formation of collagen in vitro was studied by turbidity measurements and atomic force microscopy (AFM). The kinetics curves of fibril formation indicated that the rate of collagen fibrillogenesis was decreased with the addition of CMC, meanwhile the final turbidity was obviously increased as the CMC/collagen ratio reached 30%. The AFM images of collagen-CMC solutions showed that the number of nucleation sites of collagen fibrillogenesis was significantly increased with the presence of CMC, while the diameter of immature collagen fibrils was obviously decreased. Moreover, the thermal stability of collagen fibril hydrogels was obviously improved with the presence of CMC. In addition, the morphologies of collagen fibrils observed by AFM revealed that the adjacent fibril segments or fibrils were intertwisted and even tightly merged, probably due to the hydrogen bonding and molecular entanglement interactions between CMC and collagen molecules.

  5. Morphological properties of collagen fibers in porcine lamina propria

    PubMed Central

    Johanes, Iecun; Mihelc, Elaine; Sivasankar, Mahalakshmi; Ivanisevic, Albena

    2009-01-01

    Objectives Collagen influences the biomechanical properties of vocal folds. Altered collagen morphology has been implicated in dysphonia associated with aging and scarring. Documenting the morphological properties of native collagen in healthy vocal folds is essential to understand the structural and functional alterations to collagen with aging and disease. Our primary objective was to quantify the morphological properties of collagen in the vocal fold lamina propria. Our secondary exploratory objective was to investigate the effects of pepsin exposure on the morphological properties of collagen in the lamina propria. Design Experimental, in vitro study with porcine model. Methods Lamina propria was dissected from 26 vocal folds and imaged with Atomic Force Microscopy (AFM). Morphological data on d-periodicity, diameter, and roughness of collagen fibers were obtained. To investigate the effects of pepsin exposure on collagen morphology, vocal fold surface was exposed to pepsin or sham challenge prior to lamina propria dissection and AFM imaging. Results The d-periodicity, diameter, and roughness values for native vocal fold collagen are consistent with literature reports for collagen fibers in other body tissue. Pepsin exposure on vocal fold surface did not appear to change the morphological properties of collagen fibers in the lamina propria. Conclusions Quantitative data on collagen morphology were obtained at nanoscale resolution. Documenting collagen morphology in healthy vocal folds is critical for understanding the physiological changes to collagen with aging and scarring, and for designing biomaterials that match the native topography of lamina propria. PMID:20171830

  6. Super-hydrophobic graphene coated polyurethane (GN@PU) sponge with great oil-water separation performance

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaotan; Liu, Dongyan; Ma, Yuling; Nie, Jing; Sui, Guoxin

    2017-11-01

    The graphene/polyurethane (GN@PU) sponge was prepared via simple dip-coating PU sponges in graphene aqueous suspension containing cellulose nanowhiskers (CNWs), where CNWs played a vital role to facilitate the uniform graphene sheets coated on the skeletons of polyurethane sponge (PU). The super-hydrophobic GN@PU sponge was obtained by optimizing the ratio of GN and CNWs to choose the final coating suspensions of GN/CNWs mixture or pure graphene. The GN@PU sponge showed densely packed graphene sheets, contributing super-hydrophobicity to the sponge with water contact angle of 152° and a large lubricating oil absorption value of 31 g g-1. The elasticity, mechanical durability, thermal and chemical stability were all found to be improved after coating with the thin GN layers. Moreover, the GN@PU sponges possess outstanding recyclability and stability since no decline in absorption efficiency was observed after more than 100 cycles.

  7. Corneal collagen denaturation in laser thermokeratoplasty

    NASA Astrophysics Data System (ADS)

    Brinkmann, Ralf; Kampmeier, Juergen; Grotehusmann, Ulf; Vogel, Alfred; Koop, Norbert; Asiyo-Vogel, Mary; Birngruber, Reginald

    1996-05-01

    In laserthermokeratoplasty (LTK) thermal denaturation and shrinkage of corneal collagen is used to correct hyperopia and astigmatism. In order to optimize dosimetry, the temperature at which maximal shrinkage of collagen fibrils occurs is of major interest. Since the exposure time in clinical LTK-treatment is limited to a few seconds, the kinetics of collagen denaturation as a rate process has to be considered, thus the time of exposure is of critical importance for threshold and shrinkage temperatures. We investigated the time-temperature correlation for corneal collagen denaturation within different time domains by turbidimetry of scattered HeNe laser probe light using a temperature controlled water bath and pulsed IR laser irradiation. In the temperature range of 60 degree(s)C to 95 degree(s)C we found an exponential relation between the denaturation time and temperature. For the typical LTK-treatment time of 2 s, a temperature of 95 degree(s)C is needed to induce thermal damage. Use of pulsed Holmium laser radiation gave significant scattering of HeNe laser probe light at calculated temperatures of around 100 degree(s)DC. Rate parameters according to the formalism of Arrhenius were fitted to these results. Force measurements showed the simultaneous onset of light scattering and collagen shrinkage.

  8. New recommendations for measuring collagen solubility.

    PubMed

    Latorre, María E; Lifschitz, Adrian L; Purslow, Peter P

    2016-08-01

    The heat-solubility of intramuscular collagen is usually conducted in 1/4 Ringer's solution at pH7.4, despite this ionic strength and pH being inappropriate for post-rigor meat. The current work studied the percentage of soluble collagen and hydrothermal isometric tension characteristics of perimysial strips on bovine semitendinosus muscles in either 1/4 Ringer's solution, distilled water, PBS, or a solution of the same salt concentration as 1/4 Ringer's but at pH5.6. Values of % soluble collagen were lower at pH7.4 than 5.6. Increasing ionic strength reduced % soluble collagen. The maximum perimysial isometric tension was independent of the bathing medium, but the percent relaxation was higher at pH7.4 than at pH5.6, and increased with ionic strength of the media. It is recommended that future measurements of collagen solubility and tests on connective tissue components of post-rigor meat should be carried out in a solution of concentrations NaCl and KCl equivalent to those in 1/4 Ringer's, but at pH5.6, a pH relevant to post-rigor meat. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. [Study on hydrothermal stability of the collagen].

    PubMed

    Wang, Yajuan; Chen, Hui; Shan, Zhihua

    2009-02-01

    The low hydrothermal stability of the raw collagen restricts its usage. To improve the hydrothermal stability of collagen, two kinds of materials with weak astringency were used by experts. The research proved that the synergistic effect was formed during the process. In this study, by using UV, FT-IR, 13CNMR spectra and elemental analysis on the salicylic acid and metal-salicylic complexes, we could get the structural formula of every compound. And then, the hide powder was treated with the compounds. At last, the treated hide powder was tested by DSC. It could be presumed that the Rigid Matrix formed between the collagen doses can increase the hydrothermal stability of raw collagen, The result indicated that salicylic-chrome with large stable constant was better than others in improving the heat resistance of raw collagen, and the denaturalization temperature of hide powder treated with salicylic-chrome was 146.7 degrees C. Salicylic-aluminum was in the second place, the relevant temperature being 145.7 degrees C.

  10. Flavonoids inhibit the formation of the cross-linking AGE pentosidine in collagen incubated with glucose, according to their structure.

    PubMed

    Urios, Paul; Grigorova-Borsos, Anne-Marie; Sternberg, Michel

    2007-04-01

    Glycoxidation of collagens contributes to development of vascular complications in diabetes. Since flavonoids are potent antioxidants present in vegetal foods, it was interesting to examine their effect on the formation of a cross-linking advanced glycation endproduct, pentosidine, in collagens. Collagen was incubated with glucose (250 mM), in the presence of different flavonoids. Pentosidine was measured by HPLC, hydroxyproline colorimetrically. Monomeric flavonoids (25 and 250 microM) markedly reduced pentosidine/hydroxyproline values in a concentration- and structure-dependent manner. In decreasing order of their specific inhibitory activity, they rank as follows: myricetin > or = quercetin > rutin > (+)catechin > kaempferol. Thus 3'-OH or 4-oxo + Delta(2-3) increase the inhibitory activity; conjugation by Rha-Glc on 3-OH decreases it. Procyanidin oligomers from grape seed were more active than pine bark procyanidin oligomers: this may be related to the galloyl residues present in grape seed oligomers only. Procyanidin oligomers are known to be cleaved into monomers in the gastric milieu and monomeric flavonoids to be absorbed and recovered at micromolar concentrations (with a long plasmatic half-life) in extracellular fluids, in contact with collagens. Flavonoids are very potent inhibitors of pentosidine formation in collagens. They are active at micromolar concentrations; these might be achieved in plasma of diabetic patients after oral intake of natural flavonoids.

  11. Computational methods for identifying miRNA sponge interactions.

    PubMed

    Le, Thuc Duy; Zhang, Junpeng; Liu, Lin; Li, Jiuyong

    2017-07-01

    Recent findings show that coding genes are not the only targets that miRNAs interact with. In fact, there is a pool of different RNAs competing with each other to attract miRNAs for interactions, thus acting as competing endogenous RNAs (ceRNAs). The ceRNAs indirectly regulate each other via the titration mechanism, i.e. the increasing concentration of a ceRNA will decrease the number of miRNAs that are available for interacting with other targets. The cross-talks between ceRNAs, i.e. their interactions mediated by miRNAs, have been identified as the drivers in many disease conditions, including cancers. In recent years, some computational methods have emerged for identifying ceRNA-ceRNA interactions. However, there remain great challenges and opportunities for developing computational methods to provide new insights into ceRNA regulatory mechanisms.In this paper, we review the publically available databases of ceRNA-ceRNA interactions and the computational methods for identifying ceRNA-ceRNA interactions (also known as miRNA sponge interactions). We also conduct a comparison study of the methods with a breast cancer dataset. Our aim is to provide a current snapshot of the advances of the computational methods in identifying miRNA sponge interactions and to discuss the remaining challenges. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Dendrimersomes Exhibit Lamellar-to-Sponge Phase Transitions.

    PubMed

    Wilner, Samantha E; Xiao, Qi; Graber, Zachary T; Sherman, Samuel E; Percec, Virgil; Baumgart, Tobias

    2018-05-15

    Lamellar to nonlamellar membrane shape transitions play essential roles in key cellular processes, such as membrane fusion and fission, and occur in response to external stimuli, including drug treatment and heat. A subset of these transitions can be modeled by means of thermally inducible amphiphile assemblies. We previously reported on mixtures of hydrogenated, fluorinated, and hybrid Janus dendrimers (JDs) that self-assemble into complex dendrimersomes (DMSs), including dumbbells, and serve as promising models for understanding the complexity of biological membranes. Here we show, by means of a variety of complementary techniques, that DMSs formed by single JDs or by mixtures of JDs undergo a thermally induced lamellar-to-sponge transition. Consistent with the formation of a three-dimensional bilayer network, we show that DMSs become more permeable to water-soluble fluorophores after transitioning to the sponge phase. These DMSs may be useful not only in modeling isotropic membrane rearrangements of biological systems but also in drug delivery since nonlamellar delivery vehicles can promote endosomal disruption and cargo release.

  13. Orbital cellulitis following silicone-sponge scleral buckles

    PubMed Central

    Nemet, Arie Y; Ferencz, Joseph R; Segal, Ori; Meshi, Amit

    2013-01-01

    Background Acute or chronic infection of the scleral explant is rare. We report seven cases of scleral explant infections that caused orbital cellulitis. Materials and methods This was a retrospective chart review of oculoplastics at oculoplastics and vitreo-retinal units in a secondary referral hospital. All subjects had orbital cellulitis secondary to scleral buckle in the range of January 1990 to March 2010. Demographics, imaging studies, and pathology specimens were reviewed. Results A total of 841 silicone-sponge scleral buckle implants for rhegmatogenous retinal detachment were performed. Forty were extracted (4.75%; annual rate of 1.9 cases). Seven (0.83%) had orbital cellulitis. The mean time from implantation to presentation was 5.7 years. There was bacterial growth in all specimens, with Staphylococcus aureus in four. Conclusions Patients who are operated on with silicone-sponge scleral buckling for rhegmatogenous retinal detachment sometimes require removal of the implant because of infection. However, the infection rate is low. Patients should be followed in the long term for possible complications. PMID:24204118

  14. Structure of a tetrameric galectin from Cinachyrella sp. (ball sponge)

    SciTech Connect

    Freymann, Douglas M., E-mail: freymann@northwestern.edu; Nakamura, Yuka; Focia, Pamela J.

    2012-09-01

    The structure of a tetrameric sponge galectin suggests a basis for glutamate receptor potentiation. The galectins are a family of proteins that bind with highest affinity to N-acetyllactosamine disaccharides, which are common constituents of asparagine-linked complex glycans. They play important and diverse physiological roles, particularly in the immune system, and are thought to be critical metastatic agents for many types of cancer cells, including gliomas. A recent bioactivity-based screen of marine sponge (Cinachyrella sp.) extract identified an ancestral member of the galectin family based on its unexpected ability to positively modulate mammalian ionotropic glutamate receptor function. To gain insight intomore » the mechanistic basis of this activity, the 2.1 Å resolution X-ray structure of one member of the family, galectin CchG-1, is reported. While the protomer exhibited structural similarity to mammalian prototype galectin, CchG-1 adopts a novel tetrameric arrangement in which a rigid toroidal-shaped ‘donut’ is stabilized in part by the packing of pairs of vicinal disulfide bonds. Twofold symmetry between binding-site pairs provides a basis for a model for interaction with ionotropic glutamate receptors.« less

  15. Designing a Clean Label Sponge Cake with Reduced Fat Content.

    PubMed

    Eslava-Zomeño, Cristina; Quiles, Amparo; Hernando, Isabel

    2016-10-01

    The fat in a sponge cake formulation was partially replaced (0%, 30%, 50%, and 70%) with OptiSol™5300.This natural functional ingredient derived from flax seeds, rich in fiber and alpha-linoleic acid, provides a natural substitute for guar and xanthan gums, avoiding E-numbers on labels. The structure and some physicochemical properties of the formulations were examined, sensory analysis was conducted and changes in starch digestibility due to adding this ingredient were determined. Increasing quantities of OptiSol™5300 gave harder cakes, with less weight loss during baking, without affecting the final cake height. There were no significant differences (P > 0.05) in texture, flavor and overall acceptance between the control and the 30% substitution cake, nor in the rapidly digestible starch values. Consequently, replacing up to 30% of the fat with OptiSol™5300 gives a new product with health benefits and a clean label that resembles the full-fat sponge cake. © 2016 Institute of Food Technologists®.

  16. Cell-populated collagen lattice contraction model for the investigation of fibroblast collagen interactions.

    PubMed

    Ehrlich, H Paul; Moyer, Kurtis E

    2013-01-01

    The fibroblast-populated collagen lattice (FPCL) was intended to act as the dermal component for "skin-equivalent" or artificial skin developed for skin grafting burn patients. The "skin-equivalent" was clinically unsuccessful as a skin graft, but today it is successfully used as a dressing for the management of chronic wounds. The FPCL has, however, become an instrument for investigating cell-connective tissue interactions within a three-dimensional matrix. Through the capacity of cell compaction of collagen fibrils, the FPCL undergoes a reduction in volume referred to as lattice contraction. Lattice contraction proceeds by cell-generated forces that reduce the water mass between collagen fibers, generating a closer relationship between collagen fibers. The compaction of collagen fibers is responsible for the reduction in the FPCL volume. Cell-generated forces through the linkage of collagen fibers with fibroblast's cytoskeletal actin-rich microfilament structures are responsible for the completion of the collagen matrix compaction. The type of culture dish used to cast FPCL as well as the cell number will dictate the mechanism for compacting collagen matrices. Fibroblasts, at moderate density, cast as an FPCL within a petri dish and released from the surface of the dish soon after casting compact collagen fibers through cell tractional forces. Fibroblasts at moderate density cast as an FPCL within a tissue culture dish and not released for 4 days upon release show rapid lattice contraction through a mechanism of cell contraction forces. Fibroblasts at high density cast in an FPCL within a petri dish, released from the surface of the dish soon after casting, compact a collagen lattice very rapidly through forces related to cell elongation. The advantage of the FPCL contraction model is the study of cells in the three-dimensional environment, which is similar to the environment from which these cells were isolated. In this chapter methods are described for

  17. ECM turnover-stimulated gene delivery through collagen-mimetic peptide-plasmid integration in collagen.

    PubMed

    Urello, Morgan A; Kiick, Kristi L; Sullivan, Millicent O

    2017-10-15

    Gene therapies have great potential in regenerative medicine; however, clinical translation has been inhibited by low stability and limited transfection efficiencies. Herein, we incorporate collagen-mimetic peptide (CMP)-linked polyplexes in collagen scaffolds to increase DNA stability by up to 400% and enable tailorable in vivo transgene expression at 100-fold higher levels and 10-fold longer time periods. These improvements were directly linked to a sustained interaction between collagen and polyplexes that persisted during cellular remodeling, polyplex uptake, and intracellular trafficking. Specifically, incorporation of CMPs into polyethylenimine (PEI) polyplexes preserved serum-exposed polyplex-collagen activity over a period of 14days, with 4 orders-of-magnitude more intact DNA present in CMP-modified polyplex-collagen relative to unmodified polyplex-collagen after a 10day incubation under cell culture conditions. CMP-modification also altered endocytic uptake, as indicated by gene silencing studies showing a nearly 50% decrease in transgene expression in response to caveolin-1 silencing in modified samples versus only 30% in unmodified samples. Furthermore, cellular internalization studies demonstrated that polyplex-collagen association persisted within cells in CMP polyplexes, but not in unmodified polyplexes, suggesting that CMP linkage to collagen regulates intracellular transport. Moreover, experiments in an in vivo repair model showed that CMP modification enabled tailoring of transgene expression from 4 to 25days over a range of concentrations. Overall, these findings demonstrate that CMP decoration provides substantial improvements in gene retention, altered release kinetics, improved serum-stability, and improved gene activity in vivo. This versatile technique has great potential for multiple applications in regenerative medicine. In this work, we demonstrate a novel approach for stably integrating DNA into collagen scaffolds to exploit the natural

  18. Deep sequencing reveals exceptional diversity and modes of transmission for bacterial sponge symbionts.

    PubMed

    Webster, Nicole S; Taylor, Michael W; Behnam, Faris; Lücker, Sebastian; Rattei, Thomas; Whalan, Stephen; Horn, Matthias; Wagner, Michael

    2010-08-01

    Marine sponges contain complex bacterial communities of considerable ecological and biotechnological importance, with many of these organisms postulated to be specific to sponge hosts. Testing this hypothesis in light of the recent discovery of the rare microbial biosphere, we investigated three Australian sponges by massively parallel 16S rRNA gene tag pyrosequencing. Here we show bacterial diversity that is unparalleled in an invertebrate host, with more than 250,000 sponge-derived sequence tags being assigned to 23 bacterial phyla and revealing up to 2996 operational taxonomic units (95% sequence similarity) per sponge species. Of the 33 previously described 'sponge-specific' clusters that were detected in this study, 48% were found exclusively in adults and larvae - implying vertical transmission of these groups. The remaining taxa, including 'Poribacteria', were also found at very low abundance among the 135,000 tags retrieved from surrounding seawater. Thus, members of the rare seawater biosphere may serve as seed organisms for widely occurring symbiont populations in sponges and their host association might have evolved much more recently than previously thought. © 2009 Society for Applied Microbiology and Blackwell Publishing Ltd.

  19. Deep sequencing reveals exceptional diversity and modes of transmission for bacterial sponge symbionts

    PubMed Central

    Webster, Nicole S; Taylor, Michael W; Behnam, Faris; Lücker, Sebastian; Rattei, Thomas; Whalan, Stephen; Horn, Matthias; Wagner, Michael

    2010-01-01

    Marine sponges contain complex bacterial communities of considerable ecological and biotechnological importance, with many of these organisms postulated to be specific to sponge hosts. Testing this hypothesis in light of the recent discovery of the rare microbial biosphere, we investigated three Australian sponges by massively parallel 16S rRNA gene tag pyrosequencing. Here we show bacterial diversity that is unparalleled in an invertebrate host, with more than 250 000 sponge-derived sequence tags being assigned to 23 bacterial phyla and revealing up to 2996 operational taxonomic units (95% sequence similarity) per sponge species. Of the 33 previously described ‘sponge-specific’ clusters that were detected in this study, 48% were found exclusively in adults and larvae – implying vertical transmission of these groups. The remaining taxa, including ‘Poribacteria’, were also found at very low abundance among the 135 000 tags retrieved from surrounding seawater. Thus, members of the rare seawater biosphere may serve as seed organisms for widely occurring symbiont populations in sponges and their host association might have evolved much more recently than previously thought. PMID:21966903

  20. Implementing sponge physiological and genomic information to enhance the diversity of its culturable associated bacteria.

    PubMed

    Lavy, Adi; Keren, Ray; Haber, Markus; Schwartz, Inbar; Ilan, Micha

    2014-02-01

    In recent years new approaches have emerged for culturing marine environmental bacteria. They include the use of novel culture media, sometimes with very low-nutrient content, and a variety of growth conditions such as temperature, oxygen levels, and different atmospheric pressures. These approaches have largely been neglected when it came to the cultivation of sponge-associated bacteria. Here, we used physiological and environmental conditions to reflect the environment of sponge-associated bacteria along with genomic data of the prominent sponge symbiont Candidatus Poribacteria sp. WGA-4E, to cultivate bacteria from the Red Sea sponge Theonella swinhoei. Designing culturing conditions to fit the metabolic needs of major bacterial taxa present in the sponge, through a combined use of diverse culture media compositions with aerobic and microaerophilic states, and addition of antibiotics, yielded higher diversity of the cultured bacteria and led to the isolation of novel sponge-associated and sponge-specific bacteria. In this work, 59 OTUs of six phyla were isolated. Of these, 22 have no close type strains at the species level (< 97% similarity of 16S rRNA gene sequence), representing novel bacteria species, and some are probably new genera and even families. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  1. Preparation of sponge-reinforced silica aerogels from tetraethoxysilane and methyltrimethoxysilane for oil/water separation

    NASA Astrophysics Data System (ADS)

    Li, Ming; Jiang, Hongyi; Xu, Dong

    2018-04-01

    Polyurethane sponge-reinforced silica aerogels based on tetraethoxysilane (TEOS) and methyltrimethoxysilane (MTMS) were fabricated by a facile method through sol-gel reaction followed by ambient pressure drying. In sponge-reinforced silica aerogels, nanoporous aerogel aggregates fill in the pores of polyurethane sponge. The sponge-reinforced aerogels are hydrophobic and oleophilic and show extremely high absorption for machine oil (10.6 g g‑1 for TEOS-based aerogel and 9.2 g g‑1 for MTMS-based aerogel). In addition, the sponge-reinforced aerogel composites exhibit notable improvements with regards to mechanical properties. The compressive strength was enhanced obviously up to about 349 KPa for TEOS-based aerogel and 60 KPa for MTMS-based aerogel. Specially, sponge-reinforced silica aerogels based on MTMS drastically shrank upon loading and then recovered to the original size when unloaded. The property differences of the sponge-reinforced silica aerogels caused by the two precursors were discussed in terms of morphologies, pore size distributions and chemical structure.

  2. Spiculogenesis in the siliceous sponge Lubomirskia baicalensis studied with fluorescent staining.

    PubMed

    Annenkov, Vadim V; Danilovtseva, Elena N

    2016-04-01

    Siliceous sponges are the most primitive multicellular animals whose skeleton consists of spicules - needle-like constructions from silicon dioxide surrounding organic axial filaments. Mechanisms of spicule formation have been intensively studied due to the high ecological importance of sponges and their interest to materials science. Light and electron microscopy are not appropriate enough to display the process from silicon-enriched cells to mature spicules because of composite structure of the sponge tissues. In this article, spiculogenesis in the siliceous sponge has been studied for the first time with the use of fluorescent microscopy. Fluorescent vital dye NBD-N2 was applied to stain growing siliceous structures in the sponge and primmorph cell system. The main stages of spicule growth in the fresh-water sponge Lubomirskia baicalensis (Pallas, 1773) were visualized: silicon accumulation in sclerocytes; formation of an organic filament protruding from the cell; further elongation of the filament and growth of the spicule in a spindle-like form with enlargement in the center; merger with new sclerocytes and formation of the mature spicule. Fluorescent microscopy combined with SEM allows us to overcome the virtual differentiation between intra- and extracellular mechanisms of spicule growth. The growing spicule can capture silicic acid from the extracellular space and merge with new silicon-enriched cells. Visualization of the growing spicules with the fluorescent dye allows us to monitor sponge viability in ecological or toxicological experiments and to apply genomic, proteomic and biochemical techniques. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Spherulization as a process for the exudation of chemical cues by the encrusting sponge C. crambe.

    PubMed

    Ternon, Eva; Zarate, Lina; Chenesseau, Sandrine; Croué, Julie; Dumollard, Rémi; Suzuki, Marcelino T; Thomas, Olivier P

    2016-07-06

    Ecological interactions in the marine environment are now recognized to be partly held by chemical cues produced by marine organisms. In particular, sponges are sessile animals thought to rely on the bioactive substances they synthesize to ensure their development and defense. However, the mechanisms leading the sponges to use their specialized metabolites as chemical cues remain unknown. Here we report the constant release of bioactive polycyclic guanidinic alkaloids by the Mediterranean sponge Crambe crambe into the dissolved and the particulate phases using a targeted metabolomics study. These compounds were proven to be stored into already described specialized (spherulous) sponge cells and dispersed into the water column after release through the sponge exhaling channels (oscula), leading to a chemical shield surrounding the sponge. Low concentrations of these compounds were demonstrated to have teratogenic effects on embryos of a common sea squirt (ascidian). This mechanism of action called spherulization may therefore contribute to the ecological success of encrusting sponges that need to extend their substrate cover to expand.

  4. Spherulization as a process for the exudation of chemical cues by the encrusting sponge C. crambe

    PubMed Central

    Ternon, Eva; Zarate, Lina; Chenesseau, Sandrine; Croué, Julie; Dumollard, Rémi; Suzuki, Marcelino T.; Thomas, Olivier P.

    2016-01-01

    Ecological interactions in the marine environment are now recognized to be partly held by chemical cues produced by marine organisms. In particular, sponges are sessile animals thought to rely on the bioactive substances they synthesize to ensure their development and defense. However, the mechanisms leading the sponges to use their specialized metabolites as chemical cues remain unknown. Here we report the constant release of bioactive polycyclic guanidinic alkaloids by the Mediterranean sponge Crambe crambe into the dissolved and the particulate phases using a targeted metabolomics study. These compounds were proven to be stored into already described specialized (spherulous) sponge cells and dispersed into the water column after release through the sponge exhaling channels (oscula), leading to a chemical shield surrounding the sponge. Low concentrations of these compounds were demonstrated to have teratogenic effects on embryos of a common sea squirt (ascidian). This mechanism of action called spherulization may therefore contribute to the ecological success of encrusting sponges that need to extend their substrate cover to expand. PMID:27381941

  5. Genomic analysis reveals versatile heterotrophic capacity of a potentially symbiotic sulfur-oxidizing bacterium in sponge.

    PubMed

    Tian, Ren-Mao; Wang, Yong; Bougouffa, Salim; Gao, Zhao-Ming; Cai, Lin; Bajic, Vladimir; Qian, Pei-Yuan

    2014-11-01

    Sulfur-reducing bacteria (SRB) and sulfur-oxidizing bacteria (SOB) play essential roles in marine sponges. However, the detailed characteristics and physiology of the bacteria are largely unknown. Here, we present and analyse the first genome of sponge-associated SOB using a recently developed metagenomic binning strategy. The loss of transposase and virulence-associated genes and the maintenance of the ancient polyphosphate glucokinase gene suggested a stabilized SOB genome that might have coevolved with the ancient host during establishment of their association. Exclusive distribution in sponge, bacterial detoxification for the host (sulfide oxidation) and the enrichment for symbiotic characteristics (genes-encoding ankyrin) in the SOB genome supported the bacterial role as an intercellular symbiont. Despite possessing complete autotrophic sulfur oxidation pathways, the bacterium developed a much more versatile capacity for carbohydrate uptake and metabolism, in comparison with its closest relatives (Thioalkalivibrio) and to other representative autotrophs from the same order (Chromatiales). The ability to perform both autotrophic and heterotrophic metabolism likely results from the unstable supply of reduced sulfur in the sponge and is considered critical for the sponge-SOB consortium. Our study provides insights into SOB of sponge-specific clade with thioautotrophic and versatile heterotrophic metabolism relevant to its roles in the micro-environment of the sponge body. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  6. Zooxanthellar symbionts shape host sponge trophic status through translocation of carbon.

    PubMed

    Weisz, Jeremy B; Massaro, Andrew J; Ramsby, Blake D; Hill, Malcolm S

    2010-12-01

    Sponges belonging to the genus Cliona are common inhabitants of many coral reefs, and as bioeroders, they play an important role in the carbonate cycle of the reef. Several Cliona species maintain intracellular populations of dinoflagellate zooxanthellae (i.e., Symbiodinium spp.), which also form symbioses with a variety of other invertebrates and protists (e.g., corals, molluscs, foraminifera). Unlike the case of coral symbioses, however, almost nothing is known of the metabolic interaction between sponges and their zooxanthella symbionts. To assess this interaction, we performed a tracer experiment to follow C and N in the system, performed a reciprocal transplant experiment, and measured the stable carbon isotope ratio of Cliona spp. with and without zooxanthellae to study the influence of environment on the interaction. We found strong evidence of a transfer of C from zooxanthellae to their sponge hosts but no evidence of a transfer of N from sponge to zooxanthellae. We also saw significant influences of the environment on the metabolism of the sponges. Finally, we observed significant differences in carbon metabolism of sponge species with and without symbionts. These data strongly support hypotheses of metabolic integration between zooxanthellae and their sponge host and extend our understanding of basic aspects of benthic-pelagic coupling in shallow-water marine environments.

  7. Sponge divers of the Aegean and medical consequences of risky compressed-air dive profiles.

    PubMed

    Toklu, Akin Savas; Cimsit, Maide

    2009-04-01

    Historically, Turkey once had a substantial number of professional sponge divers, a population known for a relatively high incidence of diving-related conditions such as decompression sickness (DCS) and dysbaric osteonecrosis (DON). Sponge diving ended in the mid-1980s when nearly all of the sponges in the Aegean and Mediterranean Seas contracted a bacterial disease and the occupation became unprofitable. We reviewed the records of Turkish sponge divers for information on their level of knowledge, diving equipment, dive profiles, and occupational health problems. Information was collected by: 1) interviewing former sponge divers near Bodrum, where most of them had settled; 2) reviewing the relevant literature; and 3) examining the medical records of sponge divers who underwent recompression treatment. These divers used three types of surface-supplied equipment, including hard helmets, Fernez apparatus, and hookahs; the latter were preferred because they allowed divers the greatest freedom of movement while harvesting sponges underwater. These divers used profiles that we now know involved a high risk for DCS and DON. We were able to access the records of 58 divers who had received recompression treatment. All of the cases involved severe DCS and delays from dive to recompression that averaged 72 h. Complete resolution of symptoms occurred in only 11 cases (19%). Thus, we were able to document the several factors that contributed to the risks in this occupational group, including unsafe dive profiles, resistance to seeking treatment, long delays before recompression, and the fact that recompression treatment used air rather than oxygen.

  8. Properties of Two-Variety Natural Luffa Sponge Columns as Potential Mattress Filling Materials

    PubMed Central

    Chen, Yuxia; Zhang, Kaiting; Yuan, Fangcheng; Zhang, Tingting; Weng, Beibei; Wu, Shanshan; Huang, Aiyue; Su, Na; Guo, Yong

    2018-01-01

    Luffa sponge (LS) is a resourceful material with fibro-vascular reticulated structure and extremely high porosity, which make it a potential candidate for manufacturing light mattress. In this study, two types of LS columns, namely high-density (HD) and low-density (LD) columns, were investigated as materials for filling the mattress. The results showed that the compressive strength of HD LS columns was significantly greater than that of LD LS columns. However, the densification strains of the two types of LS column were both in the range of 0.6 to 0.7. Besides, HD LS columns separately pressed to the smooth plateau region and the initial densification region exhibited a partial recovery of instant height when they were unloaded, and then both of them showed no more than 4.2% of height recovery after being allowed to rest at a constant temperature and humidity for 24 h. In contrast, when LD LS columns were compressed to the smooth plateau region, the height recovery was less than 1.62% compared to when they were pressed to the initial densification region, and that was more than 15.62%. Similar to other plant fibers used as mattress fillers, the two types of LS columns also showed good water absorption capacity—both of them could absorb water from as much as 2.07 to 3.45 times their own weight. At the same time, the two types of LS columns also showed good water desorption. The water desorption ratio of HD and LD LS columns separately reached 76.86 and 91.44%, respectively, after being let rest at a constant temperature and humidity for 13 h. PMID:29614744

  9. Energy-Absorbing Beam Member

    NASA Technical Reports Server (NTRS)

    Littell, Justin D. (Inventor)

    2017-01-01

    An energy-absorbing (EA) beam member and having a cell core structure is positioned in an aircraft fuselage proximate to the floor of the aircraft. The cell core structure has a length oriented along a width of the fuselage, a width oriented along a length of the fuselage, and a depth extending away from the floor. The cell core structure also includes cell walls that collectively define a repeating conusoidal pattern of alternating respective larger and smaller first and second radii along the length of the cell core structure. The cell walls slope away from a direction of flight of the aircraft at a calibrated lean angle. An EA beam member may include the cell core structure and first and second plates along the length of the cell core structure on opposite edges of the cell material.

  10. Collagen-Proteoglycan Relationships in Epiphyseal Cartilage

    PubMed Central

    Eisenstein, Reuben; Larsson, Sven-Erik; Sorgente, Nino; Kuettner, Klaus E.

    1973-01-01

    Columnar and hypertrophic zones of calf scapular cartilage were studied before and after extraction with 3 M guanidinium chloride (GuCl) and digestion with enzymes which degrade various components of the extracellular matrix. Morphologic and chemical analysis suggests that there are at least two anatomic pools of proteoglycan in this tissue. One, which resides between collagen fibrils, is extractable with GuCl. Another appears attached to collagen by strong bonds and is apparently not extractable with GuCl. This type of collagen-proteoglycan relationship is possibly restricted to epiphyseal cartilage. The morphology of the lacuna is different in the columnar and hypertrophic zones. Proteoglycans in the distal hypertrophic zone are less resistant to GuCl extraction. ImagesFig 9Fig 10Fig 11Fig 1Fig 2Fig 3Fig 4Fig 5Fig 6Fig 7Fig 8 PMID:4357177

  11. Biophysical behavior of Scomberoides commersonianus skin collagen.

    PubMed

    Kolli, Nagamalleswari; Joseph, K Thomas; Ramasami, T

    2002-06-01

    Some biophysical characteristics of the skin collagen from Scomberoides commersonianus were measured and compared to those of rat tail tendon. Stress-strain data indicate that the strain at break as well as the tensile strength of the fish skin without scales increased significantly. The maximum tension in case of rat skin is at least a factor of two higher than that observed in fish skin. The much lower hydrothermal isometric tension measurements observed in fish skin are attributable to a lesser number of heat stable crosslinks. Stress relaxation measurements in the fish skin indicate that more than one relaxation process may be involved in the stabilization of collagenous matrix. The observed differences in the biophysical behavior of fish skin may well arise from combination of changes in extent of hydroxylation of proline in collagen synthesis, hydrogen bond network and fibril orientation as compared to rat tail tendon.

  12. Modeling the Absorbing Aerosol Index

    NASA Technical Reports Server (NTRS)

    Penner, Joyce; Zhang, Sophia

    2003-01-01

    We propose a scheme to model the absorbing aerosol index and improve the biomass carbon inventories by optimizing the difference between TOMS aerosol index (AI) and modeled AI with an inverse model. Two absorbing aerosol types are considered, including biomass carbon and mineral dust. A priori biomass carbon source was generated by Liousse et al [1996]. Mineral dust emission is parameterized according to surface wind and soil moisture using the method developed by Ginoux [2000]. In this initial study, the coupled CCM1 and GRANTOUR model was used to determine the aerosol spatial and temporal distribution. With modeled aerosol concentrations and optical properties, we calculate the radiance at the top of the atmosphere at 340 nm and 380 nm with a radiative transfer model. The contrast of radiance at these two wavelengths will be used to calculate AI. Then we compare the modeled AI with TOMS AI. This paper reports our initial modeling for AI and its comparison with TOMS Nimbus 7 AI. For our follow-on project we will model the global AI with aerosol spatial and temporal distribution recomputed from the IMPACT model and DAO GEOS-1 meteorology fields. Then we will build an inverse model, which applies a Bayesian inverse technique to optimize the agreement of between model and observational data. The inverse model will tune the biomass burning source strength to reduce the difference between modelled AI and TOMS AI. Further simulations with a posteriori biomass carbon sources from the inverse model will be carried out. Results will be compared to available observations such as surface concentration and aerosol optical depth.

  13. Sponge erosion under acidification and warming scenarios: differential impacts on living and dead coral.

    PubMed

    Stubler, Amber D; Furman, Bradley T; Peterson, Bradley J

    2015-11-01

    Ocean acidification will disproportionately impact the growth of calcifying organisms in coral reef ecosystems. Simultaneously, sponge bioerosion rates have been shown to increase as seawater pH decreases. We conducted a 20-week experiment that included a 4-week acclimation period with a high number of replicate tanks and a fully orthogonal design with two levels of temperature (ambient and +1 °C), three levels of pH (8.1, 7.8, and 7.6), and two levels of boring sponge (Cliona varians, present and absent) to account for differences in sponge attachment and carbonate change for both living and dead coral substrate (Porites furcata). Net coral calcification, net dissolution/bioerosion, coral and sponge survival, sponge attachment, and sponge symbiont health were evaluated. Additionally, we used the empirical data from the experiment to develop a stochastic simulation of carbonate change for small coral clusters (i.e., simulated reefs). Our findings suggest differential impacts of temperature, pH and sponge presence for living and dead corals. Net coral calcification (mg CaCO3  cm(-2)  day(-1) ) was significantly reduced in treatments with increased temperature (+1 °C) and when sponges were present; acidification had no significant effect on coral calcification. Net dissolution of dead coral was primarily driven by pH, regardless of sponge presence or seawater temperature. A reevaluation of the current paradigm of coral carbonate change under future acidification and warming scenarios should include ecologically relevant timescales, species interactions, and community organization to more accurately predict ecosystem-level response to future conditions. © 2015 John Wiley & Sons Ltd.

  14. Evolution and function of eukaryotic-like proteins from sponge symbionts.

    PubMed

    Reynolds, David; Thomas, Torsten

    2016-10-01

    Sponges (Porifera) are ancient metazoans that harbour diverse microorganisms, whose symbiotic interactions are essential for the host's health and function. Although symbiosis between bacteria and sponges are ubiquitous, the molecular mechanisms that control these associations are largely unknown. Recent (meta-) genomic analyses discovered an abundance of genes encoding for eukaryotic-like proteins (ELPs) in bacterial symbionts from different sponge species. ELPs belonging to the ankyrin repeat (AR) class from a bacterial symbiont of the sponge Cymbastela concentrica were subsequently found to modulate amoebal phagocytosis. This might be a molecular mechanism, by which symbionts can control their interaction with the sponge. In this study, we investigated the evolution and function of ELPs from other classes and from symbionts found in other sponges to better understand the importance of ELPs for bacteria-eukaryote interactions. Phylogenetic analyses showed that all of the nine ELPs investigated were most closely related to proteins found either in eukaryotes or in bacteria that can live in association with eukaryotes. ELPs were then recombinantly expressed in Escherichia coli and exposed to the amoeba Acanthamoeba castellanii, which is functionally analogous to phagocytic cells in sponges. Phagocytosis assays with E. coli containing three ELP classes (AR, TPR-SEL1 and NHL) showed a significantly higher percentage of amoeba containing bacteria and average number of intracellular bacteria per amoeba when compared to negative controls. The result that various classes of ELPs found in symbionts of different sponges can modulate phagocytosis indicates that they have a broader function in mediating bacteria-sponge interactions. © 2016 John Wiley & Sons Ltd.

  15. Efficient bioremediation of total organic carbon (TOC) in integrated aquaculture system by marine sponge Hymeniacidon perleve.

    PubMed

    Fu, Wantao; Wu, Yichun; Sun, Liming; Zhang, Wei

    2007-08-15

    The aim of this study is to investigate the potential of using marine sponge Hymeniacidon perleve to remove total organic carbon (TOC) in integrated aquaculture ecosystems. In sterilized natural seawater (SNSW) with different concentrations of TOC, H. perleve removed approximately 44-61% TOC during 24 h, with retention rates of ca. 0.19-1.06 mg/h .g-fresh sponge, however no particulate selectivity was observed. The highest initial TOC concentration, in which about 2.7 g fresh sponges could remove TOC effectively in 0.5-L SNSW, is 214.3-256.9 mg/L. The highest capacity of TOC removal and clearance rate (CR) by H. perleve is ca. 25.50 mg-TOC/g-fresh sponge and 7.64 mL/h . g-fresh sponge within 24 h, respectively. Until reaching the highest TOC removal capacity, the TOC removal capacity and clearance rate of H. perleve increased with initial TOC concentration, and dropped dramatically thereafter. After reaching the highest removal capacity, H. perleve could only remove relatively lower TOC concentration in seawater in subsequent run. The TOC removal kinetics in SNSW by H. perleve fitted very well with a S-shaped curve and a Logistic model equation (R(2) = 0.999). In different volumes of SNSW with a fixed initial TOC concentration, the weight/volume ratio of sponge biomass and SFNSW was optimized at 1.46 g-fresh sponge/1-L SNSW to achieve the maximum TOC removal. When co-cultured with marine fish Fugu rubripes for 15 days, H. perleve removed TOC excreted by F. rubripes with similar retention rates of ca. 0.15 mg/h . g-fresh sponge, and the sponge biomass increased by 22.8%. (c) 2007 Wiley Periodicals, Inc.

  16. Tolerance of Sponge Assemblages to Temperature Anomalies: Resilience and Proliferation of Sponges following the 1997–8 El-Niño Southern Oscillation

    PubMed Central

    Kelmo, Francisco; Bell, James J.; Attrill, Martin J.

    2013-01-01

    Coral reefs across the world are under threat from a range of stressors, and while there has been considerable focus on the impacts of these stressors on corals, far less is known about their effect on other reef organisms. The 1997–8 El-Niño Southern Oscillation (ENSO) had notable and severe impacts on coral reefs worldwide, but not all reef organisms were negatively impacted by this large-scale event. Here we describe how the sponge fauna at Bahia, Brazil was influenced by the 1997–8 ENSO event. Sponge assemblages from three contrasting reef habitats (reef tops, walls and shallow banks) at four sites were assessed annually from 1995 to 2011. The within-habitat sponge diversity did not vary significantly across the study period; however, there was a significant increase in density in all habitats. Multivariate analyses revealed no significant difference in sponge assemblage composition (ANOSIM) between pre- and post-ENSO years for any of the habitats, suggesting that neither the 1997–8 nor any subsequent smaller ENSO events have had any measurable impact on the reef sponge assemblage. Importantly, this is in marked contrast to the results previously reported for a suite of other taxa (including corals, echinoderms, bryozoans, and ascidians), which all suffered mass mortalities as a result of the ENSO event. Our results suggest that of all reef taxa, sponges have the potential to be resilient to large-scale thermal stress events and we hypothesize that sponges might be less affected by projected increases in sea surface temperature compared to other major groups of reef organisms. PMID:24116109

  17. Methods to Analyze Bone Regenerative Response to Different rhBMP-2 Doses in Rabbit Craniofacial Defects

    DTIC Science & Technology

    2014-02-28

    sockets.6 The commercially available INFUSE system (Medtronic Spinal and Biologics, Memphis, TN), compris- ing an absorbable collagen sponge plus...a collagen sponge carrier) by Medtronics27 for bone healing in rabbits. Even the 25mg rhBMP-2 dose used showed significantly greater re- generated...visualization No 3D morphological analysis for small-animal modelsCan be repeated over course of healing for temporal trends Potential risk of X-ray

  18. Distinct Characteristics of Mandibular Bone Collagen Relative to Long Bone Collagen: Relevance to Clinical Dentistry

    PubMed Central

    Tokutomi, Kentaro; Sasaki, Michiko; Katafuchi, Michitsuna; Mizumachi, Emiri; Sato, Hironobu

    2014-01-01

    Bone undergoes constant remodeling throughout life. The cellular and biochemical mechanisms of bone remodeling vary in a region-specific manner. There are a number of notable differences between the mandible and long bones, including developmental origin, osteogenic potential of mesenchymal stem cells, and the rate of bone turnover. Collagen, the most abundant matrix protein in bone, is responsible for determining the relative strength of particular bones. Posttranslational modifications of collagen, such as intermolecular crosslinking and lysine hydroxylation, are the most essential determinants of bone strength, although the amount of collagen is also important. In comparison to long bones, the mandible has greater collagen content, a lower amount of mature crosslinks, and a lower extent of lysine hydroxylation. The great abundance of immature crosslinks in mandibular collagen suggests that there is a lower rate of cross-link maturation. This means that mandibular collagen is relatively immature and thus more readily undergoes degradation and turnover. The greater rate of remodeling in mandibular collagen likely renders more flexibility to the bone and leaves it more suited to constant exercise. As reviewed here, it is important in clinical dentistry to understand the distinctive features of the bones of the jaw. PMID:24818151

  19. Distinct characteristics of mandibular bone collagen relative to long bone collagen: relevance to clinical dentistry.

    PubMed

    Matsuura, Takashi; Tokutomi, Kentaro; Sasaki, Michiko; Katafuchi, Michitsuna; Mizumachi, Emiri; Sato, Hironobu

    2014-01-01

    Bone undergoes constant remodeling throughout life. The cellular and biochemical mechanisms of bone remodeling vary in a region-specific manner. There are a number of notable differences between the mandible and long bones, including developmental origin, osteogenic potential of mesenchymal stem cells, and the rate of bone turnover. Collagen, the most abundant matrix protein in bone, is responsible for determining the relative strength of particular bones. Posttranslational modifications of collagen, such as intermolecular crosslinking and lysine hydroxylation, are the most essential determinants of bone strength, although the amount of collagen is also important. In comparison to long bones, the mandible has greater collagen content, a lower amount of mature crosslinks, and a lower extent of lysine hydroxylation. The great abundance of immature crosslinks in mandibular collagen suggests that there is a lower rate of cross-link maturation. This means that mandibular collagen is relatively immature and thus more readily undergoes degradation and turnover. The greater rate of remodeling in mandibular collagen likely renders more flexibility to the bone and leaves it more suited to constant exercise. As reviewed here, it is important in clinical dentistry to understand the distinctive features of the bones of the jaw.

  20. Bioinspired coupled helical coils for soft tissue engineering of tubular structures - Improved mechanical behavior of tubular collagen type I templates.

    PubMed

    Janke, H P; Bohlin, J; Lomme, R M L M; Mihaila, S M; Hilborn, J; Feitz, W F J; Oosterwijk, E

    2017-09-01

    mimic collagen fiber orientation as found in nature - in collagen type I sponges. We show that the mechanical behavior of CHCs is very similar to native tissue and strengths structurally weak tubular constructs. The production procedure is relatively easy, reproducible and mechanical features can be controlled to meet different mechanical demands. This is promising in template manufacture, hence offering new opportunities in tissue engineering of tubular organs and preventing graft failure. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  1. Extracellular post-translational modifications of collagen are major determinants of biomechanical properties of fetal bovine cortical bone.

    PubMed

    Garnero, Patrick; Borel, Olivier; Gineyts, Evelyne; Duboeuf, Francois; Solberg, Helene; Bouxsein, Mary L; Christiansen, Claus; Delmas, Pierre D

    2006-03-01

    Mechanical behavior of bone depends on its mass and architecture, and on the material properties of the matrix, which is composed of a mineral phase and an organic component mainly constituted of type I collagen. Mineral accounts largely for the stiffness of bone, whereas type I collagen provides bone its ductility and toughness, i.e., its ability to undergo deformation and absorb energy after it begins to yield. The molecular mechanisms underlying the effect of alterations in type I collagen on bone mechanical properties are unclear. We used an in vitro model of fetal bovine cortical bone specimens (n = 44), where the extent of type I collagen cross-linking was modified by incubation at 37 degrees C for 0, 60, 90 and 120 days, keeping constant the architecture and the mineral content. At each incubation time, the following parameters were determined: (1) the bone concentration of enzymatic (pyridinoline; PYD and deoxypyridinoline, DPD) and non-enzymatic (pentosidine) crosslinks by HPLC, (2) the extent of aspartic acid isomerization of the type I collagen C-telopeptide (CTX) by ELISA of native (alpha CTX) and isomerized (beta CTX) forms, (3) the mineral density by DXA, (4) the porosity by micro-computed tomography and (5) the bending and compressive mechanical properties. Incubation of bone specimens at 37 degrees C for 60 days increased the level (per molecule of collagen) of PYD (+98%, P = 0.005), DPD (+42%, P = 0.013), pentosidine (+55-fold, P = 0.005), and the degree of type I collagen C-telopeptide isomerization (+4.9-fold, P = 0.005). These biochemical changes of collagen were associated with a 30% decrease in bending and compressive yield stress and a 2.5-fold increase in compressive post-yield energy absorption (P < 0.02 for all), with no significant change of bone stiffness. In multivariate analyses, the level of collagen cross-linking was associated with yield stress and post-yield energy absorption independently of bone mineral density, explaining up to

  2. [Collagens: why such a structural complexity?].

    PubMed

    Borel, J P; Monboisse, J C

    1993-01-01

    The collagens are a family of extracellular fibrillar proteins, characterized by the presence of one or several domains termed "triple helix", that are made of three polypeptide chains folded around each other. They elicit a huge worldwide research activity, marked every year by the publishing of dozens of books and thousands of papers. This family is presently represented by more than 16 individualized types, all differing by their molecular structure and by the way helical and globular domains are arranged. In any case, however, at least one triple helical domain exists. It is formed by the association of three polypeptide chains, each of them containing a glycine every three residues and many proline or hydroxyproline residues, and attests for the belonging of the protein to the collagen group. These multiple molecular forms and their specific architecture raise questions that remain unsolved. Why is this triple helix structure adopted in the case of collagens? Is it because the simple alpha helix of protein cannot extend over more than a few nanometers and is not solid enough? Why not a double helix like that of DNA? It would probably not be rigid enough. Why are there many globular domains interspersed between fibrillar ones? Probably these domains are useful for the association of peptide chains in register prior to their folding, then they participate in the transport of the elementary molecules from the synthesizing cells to their final place in the connective tissue and, finally, they insert the molecules into their specific place inside the growing fibrils. Collagen fibres as they are evidenced by histological methods, for instance in tendons, are of complex structure. Most of their constituting sub-units are type I tropocollagen molecules but they also contain in their center a filament of type V collagen that seems to serve as a guide during their edification. On the surface of the fibres are molecules of type III collagen that limit the growth in

  3. Mining Genomes of Three Marine Sponge-Associated Actinobacterial Isolates for Secondary Metabolism.

    PubMed

    Horn, Hannes; Hentschel, Ute; Abdelmohsen, Usama Ramadan

    2015-10-01

    Here, we report the draft genome sequences of three actinobacterial isolates, Micromonospora sp. RV43, Rubrobacter sp. RV113, and Nocardiopsis sp. RV163 that had previously been isolated from Mediterranean sponges. The draft genomes were analyzed for the presence of gene clusters indicative of secondary metabolism using antiSMASH 3.0 and NapDos pipelines. Our findings demonstrated the chemical richness of sponge-associated actinomycetes and the efficacy of genome mining in exploring the genomic potential of sponge-derived actinomycetes. Copyright © 2015 Horn et al.

  4. Production of indole antibiotics induced by exogenous gene derived from sponge meta