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Sample records for tissue therapieinduzierte effekte

  1. Positiv effekt af omstridt pointsystem på dansk forskningsproduktion

    DEFF Research Database (Denmark)

    Ingwersen, Peter; Larsen, Birger

    2014-01-01

    Et meget omdiskuteret pointsystem, der fordeler basismidler til forskning efter universiteternes produktivitet, har en mærkbar positiv effekt på dansk forskningsproduktion.......Et meget omdiskuteret pointsystem, der fordeler basismidler til forskning efter universiteternes produktivitet, har en mærkbar positiv effekt på dansk forskningsproduktion....

  2. Omfang og effekt af herbicidafdrift til læhegn

    DEFF Research Database (Denmark)

    Bruus, Marianne; Andersen, Helle Vibeke; Løfstrøm, Per

    2008-01-01

    Projektet "Vurdering af omfang og effekt af afdrift af ukrudtsmidler til danske læhegn eksemplificeret ved metsulfuron" har via praksisnære eksperimenter demonstreret, at bærproduktionen i danske læhegn er følsom over for afdrift af ukrudtsmidlet Ally (og dermed sandsynligvis også andre ukrudtsmi...

  3. Repetitive transkranielle Magnetstimulation zur Tinnitusbehandlung: keine Verbesserung der Effekte durch dopaminerge Rezeptorstimulation

    OpenAIRE

    Kleinjung, T; Vielsmeier, V; Frank, E; Burger, JS; Landgrabe, M; Hajak, G; Strutz, J; Langguth, B

    2010-01-01

    Einleitung: Die repetitive transkranielle Magnetstimulation (rTMS) stellt ein Instrument zur fokalen Modulation neuronaler Aktivität dar. Niedrigfrequente rTMS über dem auditorischen Kortex wird erfolgreich zur Reduktion des Tinnitusschweregrades eingesetzt. Allerdings sind die positiven Effekte als moderat zu bezeichnen und weisen eine hohe interindividuelle Streuung auf. Untersuchungen an gesunden Probanden konnten zeigen, dass die Effekte von rTMS im Bereich des Motorcortex durch gleichze...

  4. The knowledge status EFFEKT: Efficiency shortage. Basis for further research

    International Nuclear Information System (INIS)

    Doorman, Gerard; Grande, Ove S.

    2002-02-01

    This report gives a survey of results from the ''Norges forskningsraad'' ( The Norwegian Research Council) program EFFEKT (1996-2000) and some other relevant projects. The report focuses on areas relevant to the efficiency shortage problems and is made as a part of the foundation for the start of the competence project ''Competence Building - Capacity Shortage''. The challenge is to find adequate solutions that satisfies the demands from market participants, systems operators and market actors. This mainly contains problems of both operational and long term strategic character which primarily touches the following main areas: Peak load coverage, operating security and reserves, network capacity and environmental aspects. The results are reported under these headings from several relevant projects. The major challenges in the future will be: 1) Development of mechanisms that bring the right incentives for improved use of the flexibility in the end consumption. 2) Adaptation of the market and organisational conditions in order to improve the consumer flexibility. 3) Further development of the incentive structures for the network owners and systems operators so that the existing transferring capacity is used as well as possible and the macro economic development of the network is encouraged. 4) Profit estimations and financing of larger co-originated connections particularly across the country borders, in deregulated power markets. Particularly the first two challenges are probably a condition for the deregulated power markets as the Nordic one, shall be able to survive in the long run. In an appendix main data studied in the projects as a basis for this report, are referred

  5. Analyse af IPCC delrapport 2 - Effekter, klimatilpasning og sårbarhed

    DEFF Research Database (Denmark)

    Christensen, Jens Hesselbjerg; Arnbjerg-Nielsen, Karsten; Grindsted, Aslak

    . Med afsæt i denne delrapport er der udarbejdet en dansk analyse, der nærmere beskriver effekterne af et ændret klima i Danmark suppleret med den seneste danske forskning udført af det danske Center for Regional Changes in the Earth System (CRES). ”Analyse af IPCC delrapport 2 – Effekter...

  6. Experimental investigations on the mechanisms of the warm prestress effect; Experimentelle Untersuchungen zu den Mechanismen des WPS-Effekts

    Energy Technology Data Exchange (ETDEWEB)

    Roos, E.; Alsmann, U. [Stuttgart Univ. (Germany). Staatliche Materialpruefungsanstalt

    1998-11-01

    The Government-supported, joint project by IWW Freiburg, BAM Berlin, IWW Magdeburg, and MPA Stuttgart is intended to yield insight into the mechanisms underlying the WPS, warm prestress effect, and to derive on this basis a quantitative description of the WPS effect. (orig./CB) [Deutsch] Ziel eines durch das BMBF gefoerderten Gemeinschaftsprojekts von IWW Freiburg, BAM Berlin, IWW Magdeburg und MPA Stuttgart ist es, die Mechanismen des WPS-(warm prestress)-Effekts zu erklaeren und auf dieser Basis eine quantitative Beschreibung des WPS-Effekts zu ermoeglichen. (orig./MM)

  7. Anzeichen einer linearen dosis-effekt beziehung bei sehr kleinen bestrahlungsdosen

    CERN Document Server

    Diehl, I.

    1980-01-01

    Zur Aufstellung einer Strahlungsdosis - Effekt - Kurve bei kleinen Dosen wurde der Mikrokerntest verwendet, da er relativ einfach und gleich- zeitig sehr empfindlich ist. Die Bohne Vicia Faba (Fillbasket) wurde mit 60Co Gammastrahlen und mit hochenergetischen Neutronen bestrahlt. Die Neutronen wurden von 600 MeV Protonen, die auf ein Be—Target auftrafen produziert und unter einem Winkel von 0 Grad extrahiert. Informationen fiber Dosimetrie und Eigenschaften der verwandeten Strahlung wurder bereits an anderer Stelle beschriebenl) des gleichen auch Einzelheiten fiber die Aufzucht der BORE Vicia Fabaz). Nach der Bestrahlung wurden jeweils 5 Bohnen zu bestimmten Zeitpunkten fixiert und danach die Prfiparate herge— stellt. Pro Préparat wurden 1000 Zellen ausgewertet.

  8. Vårddjur och deras effekter på hälsan : En litteraturstudie

    OpenAIRE

    Högberg Kalmering, Camilla

    2014-01-01

    Bakgrund: Ett grundläggande emotionellt behov hos människan är fysisk beröring, som vid vissa sjukdomstillstånd kan vara svåra att tillfredsställa inom vården. Effekten av beröringen gör att människan blir mer avslappnad, samma effekt kan en person få från fysisk beröring av sällskapsdjur. Djurassisterad terapi kan användas som en kompletteringsbehandling inom sjukvården. Syfte: Att beskriva vilka djurarter som används i djurassisterad terapi och på vilket sätt de kan användas i vården för re...

  9. Samtalegrupper for personer med Aspergers syndrom. En kvalitativ studie av hva fagpersoner forteller om planlegging, gjennomføring og effekt av samtalegrupper for personer med Aspergers syndrom

    OpenAIRE

    Jensen, Øyvind

    2014-01-01

    Denne oppgaven er skrevet ut fra problemstillingen: Hvordan beskriver fagpersoner planlegging, gjennomføring og effekt av samtalegrupper for personer med Aspergers syndrom? Den belyser teori om Aspergers syndrom, effekt av samtalegrupper samt andre viktige forhold i tilknytning til samtalegruppe, som kommunikasjon, veiledning og psykoedukasjon. Fire informanter fra nettverket «Nasjonalt fagutviklingsnettverk om psykoedukative grupper for personer med Aspergers syndrom» ble intervjuet, ...

  10. Funktionelle in vitro-Effekte CAMP/CGMP-modulierender Pharmaka am humanen Detrusormuskel

    Directory of Open Access Journals (Sweden)

    Ückert St

    2002-01-01

    Full Text Available Die zyklischen Nukleotidmonophosphate cAMP und cGMP regulieren als intrazelluläre Second Messenger zahlreiche Gewebe- und Organfunktionen. cAMP und cGMP werden von zellulären Adenylat- und Guanylatzyklasen synthetisiert und von Phosphodiesterasen degradiert, die somit Schlüsselenzyme im Prozeß der Tonusregulation glatter Muskulatur sind. Die Markteinführung des PDE5-Inhibitors Sildenafil (Viagra hat dem Konzept der PDE-Inhibition auch in der Urologie breite Akzeptanz verschafft. Eigene Arbeiten der vergangenen Jahre beschreiben die Präsenz der PDE-Isoenzyme 1, 2, 3, 4 und 5 in der Muskulatur des humanen Detrusors und zeigen das klinische Potential des PDE1-Inhibitors Vinpocetin in der Behandlung der motorischen Dranginkontinenz. Mit dem Ziel der Charakterisierung geeigneter Substanzen für die Pharmakotherapie der Detrusorhyperaktivität haben wir die in vitro-Effekte neuer, selektiver Inhibitoren der PDE des Typs 2, 3 und 5 auf isolierte humane Detrusormuskulatur untersucht und mit denen des Diterpens Forskolin (Aktivator der Adenylatzyklase und der Stickoxid (NO-Donatoren Dihydropyridin (DHP und Na+Nitroprussid (NNP verglichen.

  11. Sverige, EU och Brexit – effekter, våndor och vägval

    Directory of Open Access Journals (Sweden)

    Fägersten Björn

    2017-11-01

    Full Text Available Brexit sätter Sverige i svår strategisk situation. Storbritannien har varit en nära partner i EU-samarbetet och har på olika områden skyddat Sverige och dess preferenser. Denna artikel utgår från Sveriges förhållande till EU och analyserar sedan djupet och bredden i det svensk-brittiska samarbetet och vilka effekter Sverige kan räkna med efter Brexit. Vidare diskuteras hur Sverige har debatterat och förberett sig för denna situation och vilka framtida vägval landet står inför. Det konstateras att priset för att ta över Storbritanniens roll som skeptiker inom säkerhetspolitiken och som vakthund gentemot eurozonen är högt och att Sverige lär tvingas hushålla med sitt politiska kapital. Ett mer lojalt Sverige är att vänta, och kanske också en medlem som sent omsider hittar sin egen roll inom den europeiska integrationen.

  12. Pesticiders vekselvirkning med jordbearbejdning og gødskning. Effekter på fauna og mikroflora, og på udvalgte økosystem-funktioner

    DEFF Research Database (Denmark)

    Petersen, S O; Kjærgaard, Charlotte; Elsgaard, Lars

    Dette projekt har undersøgt vekselvirkninger mellem to pesticider og hhv. jordbearbejdning (direkte sået eller pløjet jord) og gødskning (handels- eller husdyrgødning) med hensyn til effekter på regnorme, mikroleddyr og mikrobielle indikatorer og på udvalgte økosystem-tjenester (funktioner)....

  13. Therapeutische Effekte von Iloprost und dem PDE 3/4-Inhibitor Tolafentrin im Modell der Monocrotalin-induzierten chronischen pulmonalen Hypertonie der Ratte

    OpenAIRE

    Kreißelmeier, Klaus-Peter

    2010-01-01

    Die schwere pulmonale Hypertonie ist eine erheblich die Lebensqualität einschränkende Erkrankung mit einer hohen Mortalität. Wir untersuchten die therapeutischen Effekte von Iloprost, einem langwirksamen Prostazyklinanalogon, und dem dual-selektiven Phosphodiesterase 3/4-Inhibitor Tolafentrin während akuter Gabe sowie bei Dauertherapie in einem Tiermodell der Monocrotalin-induzierten pulmonalen Hypertonie der Ratte. Achtundzwanzig Tage nach Gabe des Alkaloids war der rechtsventrikuläre syste...

  14. Giver specifik fodtræning og indlæg en yderligere effekt sammenlignet med et standard knæfokuseret træningsforløb for patienter med patellofemoral smertesyndrom?

    DEFF Research Database (Denmark)

    Mølgaard, Carsten; Andreasen, Jane; Christensen, Marianne

    tilstrækkelig evidens for en overbevisende effekt af fod- og knæortoser i behandlingen af PFPS patienter. Formål: At undersøge om en kombination af specifik fodtræning og indlæg kan forbedre effekten af et standard træningsregime i behandlingen af patellofemorale smerte syndrom (PFPS). Materiale og metode...

  15. Marlene Wind efterlyser selvransagelse: Medierne spåede igen forkert. Denne gang om Brexit og Trumps effekt på Europa

    DEFF Research Database (Denmark)

    Wind, Marlene

    2017-01-01

    Torsdag d. 11 maj, var centerleder og professor ved Center for Europæisk Politik aktuel med en kronik i Politiken med titlen: ”Marlene Wind efterlyser selvransagelse: Medierne spåede igen forkert. Denne gang om Brexit og Trumps effekt på Europa”. Professorens indspark i debatten går på, at medierne...... allerede inden valget havde en ’antielitedagsorden’, og valget af Emmanuel Macron derfor bør henlede til selvransagelse i det danske medielandskab. ”Selvransagelsen burde derfor være lige så stor efter valget af Macron som den, mediefolk opviste efter valget af Trump og Brexit, da de sendte deres bedste...

  16. Teratogene effekter av antiepileptika

    Directory of Open Access Journals (Sweden)

    Bernt A. Engelsen

    2009-10-01

    Full Text Available  SAMMENDRAGCa. 1 av 200 gravide har epilepsi. Gravide med epilepsi har økt risiko for visse obstetriske komplikasjonerog for å føde barn med medfødte misdannelser. Risikoen for misdannelser synes koblet til bruk avantiepileptika under svangerskapet, og ikke til selve epilepsien. Alle typer misdannelser er økt, men leppeganespalteog nevralrørsdefekter utgjør særlig viktige misdannelser. Årsakene til misdannelsene er multifaktorielle.Bruk av antiepileptika i monoterapi kan sies å gi en individuell risiko for større misdannelser påca. 4-6%. Karbamazepin og natriumvalproat gir hhv. 0,5-1% og 2-3% risiko for nevralrørsdefekt. Samletrisiko for større og mindre anomalier inkludert dysmorfe ansiktstrekk synes ikke å overstige 10%. ENGLISH SUMMARYEngelsen BA. Teratogenic effects of antiepileptic drugs. Nor J Epidemiol 1997; 7 (1: 23-28.Approximately 1 in 200 pregnant women have epilepsy, and 1 in 250 births are to children of mothers whouse antiepleptic drugs (AED. Pregnant women with epilepsy have increased risk for certain obstetricalcomplications, and for giving birth to children with congenital malformations. The increased risk forcongenital malformations seems connected to the use of AED, not to the epileptic syndromes. The etiologyof congenital malformations are multifactorial. Use of AED in monotherapy is associated with anindividual risk of giving birth to a child with a major malformation of 4-6%. The specific risk of spinabifida is 0,5 to 1% for carbamazepine and 2-3% for sodium valproate.

  17. Investigation of the warm prestress effect by X-ray and microfractographic measurements; Roentgenografische und mikrofraktografische Untersuchungen zum Warmvorbeanspruchungs (WPS) - Effekt

    Energy Technology Data Exchange (ETDEWEB)

    Blumenauer, H.; Eichler, B.; Krempe, M.; Ude, J. [Magdeburg Univ. (Germany). Inst. fuer Werkstofftechnik und Werkstoffpruefung

    1998-11-01

    The work reported was to investigate the changes caused at the crack tip of a specimen with incipient crack and to assess their effects with regard to component fracture. The steels selected for testing are the pressure vessel steels 10MnMoNi5-5 and 17MoV8-4, and the experiments were made with CT-25 specimens. The conclusion drawn from the results obtained is that the WPS effect is due to a stronger energy dissipation in the prestressed area ahead of the crack tip, assisted by intrinsic stress-induced crack closing. (orig./CB) [Deutsch] Das Ziel dieser Arbeit ist es, die durch eine Vorbeanspruchung angerissener Proben hervorgerufenen Veraenderungen an der Rissspitze und ihre Auswirkungen auf das Bruchverhalten zu untersuchen. Die Untersuchungen wurden an den Druckbehaelterstaehlen 10MnMoNi5-5 und 17MoV8-4 durchgefuehrt. Die Versuche wurden an CT-25-Proben durchgefuehrt. Die Autoren kommen zum Schluss, dass der WPS-Effekt mit einer staerkeren Energiedissipation in der vorgeschaedigten Prozesszone vor der Rissspitze, unterstuetzt durch eigenspannungsbedingtes Rissschliessen, erklaert werden kann. (orig./MM)

  18. Stress og belastning eller effekt

    DEFF Research Database (Denmark)

    Netterstrøm, Bo

    2012-01-01

    on health is dependent on the strength and duration of the stressors, how the situation is perceived, the resources of the individual, and to what extend coping succeeds. An increase in the prevalence of reported stress in the working population in Denmark has occurred from 1987 (8%) to 2005 (12%).......Stress is in medical terms a condition characterized by physiological reactions and symptoms initiated by stressors. The physiological reactions increase the tone in the sympathetic nervous system, change metabolism in a catabolic direction and stimulate immunological reactions. The effect...

  19. Potentielt gunstige effekter af klimaforandringer

    DEFF Research Database (Denmark)

    Hitz, Mette Friberg; Jensen, Jens Erik Beck

    2009-01-01

    Climate changes have many unbeneficial effects on human health, but may also have beneficial effects. An increased mean temperature reduces the incidence of death due to hypothermia and cardiovascular disease and may increase exercise frequency. As the ozone layer decreases, the synthesis...

  20. Visuella Effekter Inom Genrespecifik Musikvideoproduktion

    OpenAIRE

    Adler, Robert; Eriksson, Andreas

    2010-01-01

    Today almost every artist has a music video. With today’s technology it has become a lot easier for smaller companies or amateur filmers to produce and distribute their work. But how important is an artist’s music video and where do people find their music these days? Other questions we wanted to answer were if there is a typical way a music video looks like based on its genre. And is it possible to break these stereotypical ways of producing music videos and thereby create a higher level of ...

  1. Stress og belastning eller effekt

    DEFF Research Database (Denmark)

    Netterstrøm, Bo

    2012-01-01

    Stress is in medical terms a condition characterized by physiological reactions and symptoms initiated by stressors. The physiological reactions increase the tone in the sympathetic nervous system, change metabolism in a catabolic direction and stimulate immunological reactions. The effect on hea...

  2. Leitsymptomvorlesungen im klinischen Studienabschnitt - Effekte evaluationsbasierter Interventionen auf eine Großgruppen-Lehrveranstaltung [Lectures based on cardinal symptoms in undergraduate medicine - effects of evaluation-based interventions on teaching large groups

    Directory of Open Access Journals (Sweden)

    Kuhnigk, Olaf

    2011-02-01

    Studienreform an der Medizinischen Fakultät der Universität Hamburg im Jahr 2004 wurden im reformierten klinischen Curriculum die fachspezifischen Vorlesungen durch Leitsymptomvorlesungen (LSV ersetzt, die sich durch alle sechs Themenblöcke der Studienjahre drei bis fünf ziehen. Da die regelmäßigen Trimesterabschlussevaluationen der Studierenden auf einen Verbesserungsbedarf der LSV hindeuteten, wurde in dieser Studie die LSV mit Terminevaluationen durch anwesende Studierende und durch geschulte Auditoren (PJ-Studierende und wissenschaftliche Mitarbeiter untersucht. Auf der Basis dieser Ergebnisse erfolgte ein schriftliches Feedback der Evaluationsdaten an die Lehrenden in Kombination mit Informationsmaterial über eine optimale Gestaltung der LSV nach modernen didaktischen Gesichtspunkten. In einer zweiten Erhebung wurden die Effekte der Intervention untersucht. Es zeigte sich, dass auf der Ebene von Schulnoten nach der Intervention nur geringe Verbesserungen der Qualität der LSV bemerkbar waren. In der Bewertung der Einzelmerkmale, insbesondere zur didaktischen Qualität, ließen sich hingegen signifikante Verbesserungen aufzeigen. Insgesamt bewerteten Studierende die LSV in der ersten Erhebungsphase bezogen auf die Einzelmerkmale signifikant positiver als die geschulten Auditoren. Dieser Effekt war in der zweiten Erhebungsphase nicht mehr nachweisbar. Unter den Auditoren bestand eine gute Inter-Rater-Reliabilität. Durch diese Untersuchung wurde insbesondere deutlich, dass die Einbettung von Lehrveranstaltungen auf struktureller und personeller Ebene in curriculare Gesamtkonzepte regelmäßig durch Qualitätssicherungsmaßnahmen zu begleiten ist. Wie häufig und in welcher Form strukturierte Rückmeldungen nach Evaluationen erfolgen müssen, um nachhaltige Effekte auf die didaktische Qualität der Lehrveranstaltungen zu haben, müssen zukünftige Studien zeigen.

  3. Tissue engineering

    CERN Document Server

    Fisher, John P; Bronzino, Joseph D

    2007-01-01

    Increasingly viewed as the future of medicine, the field of tissue engineering is still in its infancy. As evidenced in both the scientific and popular press, there exists considerable excitement surrounding the strategy of regenerative medicine. To achieve its highest potential, a series of technological advances must be made. Putting the numerous breakthroughs made in this field into a broad context, Tissue Engineering disseminates current thinking on the development of engineered tissues. Divided into three sections, the book covers the fundamentals of tissue engineering, enabling technologies, and tissue engineering applications. It examines the properties of stem cells, primary cells, growth factors, and extracellular matrix as well as their impact on the development of tissue engineered devices. Contributions focus on those strategies typically incorporated into tissue engineered devices or utilized in their development, including scaffolds, nanocomposites, bioreactors, drug delivery systems, and gene t...

  4. Tissue types (image)

    Science.gov (United States)

    There are 4 basic types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue. Connective tissue ... and binds them together (bone, blood, and lymph tissues). Epithelial tissue provides a covering (skin, the linings of ...

  5. Experimental and numerical investigations on the applicability of local approach methods on the warm prestress effect; Experimentelle und numerische Untersuchungen zur Anwendbarkeit von Local-Approach-Ansaetzen auf WPS-Effekt

    Energy Technology Data Exchange (ETDEWEB)

    Roos, E.; Elsaesser, K. [Stuttgart Univ. (Germany). Staatliche Materialpruefungsanstalt

    1998-11-01

    The three materials 10 MnMoNi 5 5, as a welded specimen, 22 NiMoCr 3 7 mod., and 17 MoV 8 4 mod. have been examined as a part of project work. The major known influencing variables with respect to the WPS effect are materials hardening, crack tip blunting, and the developing residual stress field. The project task was to investigate to what extent the finite element method will be able to describe these influencing variables. Using the damaging model of Rousselier it is possible to simulate the processes during warm prestressing at upper-shelf toughness while taking into account the crack growth. Using the parameter derived with the Beremin model with notched specimens and applying these to pre-cracked specimens will not yield accurate results describing the fracture toughness in the area affected by embrittlement. (orig./CB) [Deutsch] Im Rahmen des Forschungsprojektes wurden die drei Werkstoffe 10 MnMoNi 5 5 formgeschweisst, 22 NiMoCr 3 7 mod. und 17 MoV 8 4 mod. untersucht. Als hauptsaechliche Einflussgroessen fuer den WPS-Effekt gelten die Werkstoffverfestigung, die Abstumpfung der Rissspitze (Blunting), sowie das sich ausbildende Eigenspannungsfeld. Es wurde untersucht, inwieweit es mit Hilfe der Methode der Finiten Elemente moeglich ist, die einzelnen Einflussgroessen zu beschreiben. Mit Hilfe des Schaedigungsmodelles von Rousselier koennen die Vorgaenge beim Warmvorbelasten in der Zaehigkeitshochlage auch unter Beruecksichtigung von Risswachstum simuliert werden. Bei Verwendung der an gekerbten Proben ermittelten Parameter des Beremin-Modelles und deren Uebertragung auf angerissene Proben wird die Bruchzaehigkeit im Sproedbruchgebiet nicht zutreffend berechnet. (orig./MM)

  6. Tissue Classification

    DEFF Research Database (Denmark)

    Van Leemput, Koen; Puonti, Oula

    2015-01-01

    Computational methods for automatically segmenting magnetic resonance images of the brain have seen tremendous advances in recent years. So-called tissue classification techniques, aimed at extracting the three main brain tissue classes (white matter, gray matter, and cerebrospinal fluid), are now...... well established. In their simplest form, these methods classify voxels independently based on their intensity alone, although much more sophisticated models are typically used in practice. This article aims to give an overview of often-used computational techniques for brain tissue classification....... Although other methods exist, we concentrate on Bayesian modeling approaches, in which generative image models are constructed and subsequently ‘inverted’ to obtain automated segmentations. This general framework encompasses a large number of segmentation methods, including those implemented in widely used...

  7. Tissue Classification

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, David Gerald [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    The project began as a e ort to support InLight and Lumidigm. With the sale of the companies to a non-New Mexico entity, the project then focused on supporting a new company Medici Technologies. The Small Business (SB) is attempting to quantify glucose in tissue using a series of short interferometer scans of the nger. Each scan is produced from a novel presentation of the nger to the device. The intent of the project is to identify and, if possible, implement improved methods for classi cation, feature selection, and training to improve the performance of predictive algorithms used for tissue classi cation.

  8. Tissue irradiator

    International Nuclear Information System (INIS)

    Hungate, F.P.; Riemath, W.F.; Bunnell, L.R.

    1975-01-01

    A tissue irradiator is provided for the in-vivo irradiation of body tissue. The irradiator comprises a radiation source material contained and completely encapsulated within vitreous carbon. An embodiment for use as an in-vivo blood irradiator comprises a cylindrical body having an axial bore therethrough. A radioisotope is contained within a first portion of vitreous carbon cylindrically surrounding the axial bore, and a containment portion of vitreous carbon surrounds the radioisotope containing portion, the two portions of vitreous carbon being integrally formed as a single unit. Connecting means are provided at each end of the cylindrical body to permit connections to blood-carrying vessels and to provide for passage of blood through the bore. In a preferred embodiment, the radioisotope is thulium-170 which is present in the irradiator in the form of thulium oxide. A method of producing the preferred blood irradiator is also provided, whereby nonradioactive thulium-169 is dispersed within a polyfurfuryl alcohol resin which is carbonized and fired to form the integral vitreous carbon body and the device is activated by neutron bombardment of the thulium-169 to produce the beta-emitting thulium-170

  9. Photochemical tissue bonding

    Science.gov (United States)

    Redmond, Robert W [Brookline, MA; Kochevar, Irene E [Charlestown, MA

    2012-01-10

    Photochemical tissue bonding methods include the application of a photosensitizer to a tissue and/or tissue graft, followed by irradiation with electromagnetic energy to produce a tissue seal. The methods are useful for tissue adhesion, such as in wound closure, tissue grafting, skin grafting, musculoskeletal tissue repair, ligament or tendon repair and corneal repair.

  10. Tissue Photolithography

    Science.gov (United States)

    Wade, Lawrence A.; Kartalov, Emil; Shibata, Darryl; Taylor, Clive

    2011-01-01

    Tissue lithography will enable physicians and researchers to obtain macromolecules with high purity (greater than 90 percent) from desired cells in conventionally processed, clinical tissues by simply annotating the desired cells on a computer screen. After identifying the desired cells, a suitable lithography mask will be generated to protect the contents of the desired cells while allowing destruction of all undesired cells by irradiation with ultraviolet light. The DNA from the protected cells can be used in a number of downstream applications including DNA sequencing. The purity (i.e., macromolecules isolated form specific cell types) of such specimens will greatly enhance the value and information of downstream applications. In this method, the specific cells are isolated on a microscope slide using photolithography, which will be faster, more specific, and less expensive than current methods. It relies on the fact that many biological molecules such as DNA are photosensitive and can be destroyed by ultraviolet irradiation. Therefore, it is possible to protect the contents of desired cells, yet destroy undesired cells. This approach leverages the technologies of the microelectronics industry, which can make features smaller than 1 micrometer with photolithography. A variety of ways has been created to achieve identification of the desired cell, and also to designate the other cells for destruction. This can be accomplished through chrome masks, direct laser writing, and also active masking using dynamic arrays. Image recognition is envisioned as one method for identifying cell nuclei and cell membranes. The pathologist can identify the cells of interest using a microscopic computerized image of the slide, and appropriate custom software. In one of the approaches described in this work, the software converts the selection into a digital mask that can be fed into a direct laser writer, e.g. the Heidelberg DWL66. Such a machine uses a metalized glass plate (with

  11. In vivo tissue engineering of musculoskeletal tissues.

    Science.gov (United States)

    McCullen, Seth D; Chow, Andre G Y; Stevens, Molly M

    2011-10-01

    Tissue engineering of musculoskeletal tissues often involves the in vitro manipulation and culture of progenitor cells, growth factors and biomaterial scaffolds. Though in vitro tissue engineering has greatly increased our understanding of cellular behavior and cell-material interactions, this methodology is often unable to recreate tissue with the hierarchical organization and vascularization found within native tissues. Accordingly, investigators have focused on alternative in vivo tissue engineering strategies, whereby the traditional triad (cells, growth factors, scaffolds) or a combination thereof are directly implanted at the damaged tissue site or within ectopic sites capable of supporting neo-tissue formation. In vivo tissue engineering may offer a preferential route for regeneration of musculoskeletal and other tissues with distinct advantages over in vitro methods based on the specific location of endogenous cultivation, recruitment of autologous cells, and patient-specific regenerated tissues. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Tissue engineering; strategies, tissues, and biomaterials.

    Science.gov (United States)

    Bakhshandeh, Behnaz; Zarrintaj, Payam; Oftadeh, Mohammad Omid; Keramati, Farid; Fouladiha, Hamideh; Sohrabi-Jahromi, Salma; Ziraksaz, Zarrintaj

    2017-10-01

    Current tissue regenerative strategies rely mainly on tissue repair by transplantation of the synthetic/natural implants. However, limitations of the existing strategies have increased the demand for tissue engineering approaches. Appropriate cell source, effective cell modification, and proper supportive matrices are three bases of tissue engineering. Selection of appropriate methods for cell stimulation, scaffold synthesis, and tissue transplantation play a definitive role in successful tissue engineering. Although the variety of the players are available, but proper combination and functional synergism determine the practical efficacy. Hence, in this review, a comprehensive view of tissue engineering and its different aspects are investigated.

  13. Effekte und Nachhaltigkeit von Trainingsworkshops für den mündlich-praktischen Teil des M2-Examens [Effects and Sustainability of Trainings for the Oral and Practical Part of the German Final Exam in Medicine

    Directory of Open Access Journals (Sweden)

    Öchsner, Wolfgang

    2013-08-01

    zwischen den Teilnehmer-Subgruppen.Methode: Alle 367 Teilnehmer der bisherigen Ulmer Prüfertrainings (2007 – 20012 wurden per e-Mail angeschrieben. 63 Personen beantworteten die Umfrage, die insgesamt 28 Items zu demografischen Daten und zu Effektivität und Nachhaltigkeit der Trainings enthielt. Ergebnisse: Es ließen sich 6 wesentliche Trainingseffekte nachweisen (Trainingseffekte, die von mindestens zwei Dritteln der Befragungsteilnehmer auf einer Skala von 1 = „trifft zu“ bis 6 = „trifft nicht zu“ mit den Skalenstufen 1 oder 2 beantwortet wurden; kumulierte Prozentzahl in Klammern: Die Antworten der Teilnehmer, deren Training länger als 2 Jahre zurücklag, unterschieden sich nicht signifikant von den Antwortmittelwerten der übrigen Teilnehmer, was für die Nachhaltigkeit der Trainingseffekte spricht.Teilnehmer ohne relevante Vorerfahrung als Prüfer profitierten signifikant stärker von den Trainings, insbesondere in den Bereichen Stressreduktion, Sicherheit in der Notenfindung und kritischere Notengebung.Schlussfolgerung: Die Studie liefert Hinweise für nachhaltig positive Effekte der M2-Prüfertrainings, die für die weitere Durchführung der Trainings sprechen, insbesondere als Trainingsangebot für unerfahrene Prüfer. Die Ausweitung der Trainings erscheint daher auch für Prüfer in den M1-Prüfungen sinnvoll.

  14. Præventiv effekt af cykelhjelme

    DEFF Research Database (Denmark)

    Nielsen, C T; Larsen, C F; Nordentoft, E

    1990-01-01

    with bicycle accidents. When a bicycle helmet is purchased, it is important to ensure that the helmet fits the head, that vision is not impeded and that the chinstrap secures the helmet correctly. Legislation is necessary to ensure that bicycle helmets sold in Denmark fulfill the minimum safety requirements....

  15. Effekter af slægtspleje

    DEFF Research Database (Denmark)

    Knudsen, Lajla; Egelund, Tine

    Slægtspleje er en relativt ny anbringelsesform i Danmark, og den anvendes endnu kun i beskedent omfang. Denne rapport sammenligner effekterne af slægtspleje med effekterne af traditionel familiepleje, og den har til formål at danne et vidensgrundlag for den socialpolitiske diskussion om slægtsple...

  16. Effekte von Hyperoxie und Stickstoffmonoxid beim Neugeborenen

    OpenAIRE

    Höhn, Thomas

    2002-01-01

    In der vorliegenden Arbeit sind Untersuchungen vorgestellt, die sich mit Wirkungen und Interaktionen von zwei ubiquitär im menschlichen Körper vorkommenden Gasen befassen, i.e. Sauerstoff und Stickstoffmonoxid. Im Falle beider Substanzen ermöglicht die geringe Größe der Moleküle eine freie Diffusion über Membranen hinweg, eine Eigenschaft, die für die Funktion der Signaltransduktion geradezu prädestiniert. Aus den vorgelegten Untersuchungen lassen sich die folgenden Folgerungen ableiten: * S...

  17. Effekt af brug af tolk i psykoterapi

    DEFF Research Database (Denmark)

    Jensen, Rikke Sander; Hansen, Trine Maria Nørregaard; Carlsson, Jessica Mariana

    2017-01-01

    was used or not. On the other hand, the inclusion of an interpreter affects the therapeutic alliance and the relationships between the parties. The role of the interpreter in psychotherapy is characterized by diversity, and the included studies indicate the need for training to improve the cooperation...

  18. Socialkonstruktionisme i praksis med operativ effekt

    DEFF Research Database (Denmark)

    Barfod, Jakob Rømer

    2011-01-01

    of others and risk their own lives in order to achieve specific goals. An important part of the preparation is a process of creating a common language and shared concepts between team members. The author of this article, Major Jakob Rømer Barfod, shows how this is achieved through a newly developed and very...

  19. Socialkonstruktionisme i praksis med operativ effekt

    DEFF Research Database (Denmark)

    Barfod, Jakob Rømer

    2011-01-01

    Leadership with an operational effect The Danish Defense is undergoing radical changes. Traditionally, learning has sprung from a linear thinking with great emphasis on analysis of cause and effect. Today the Danish Defense needs to function as a deployable armed force conducting operations abroad...... successful program called ’leadership with operative effect’ based on social constructionist ideas. The Major has firsthand experience with the process from his Work in Afghanistan and has also worked with the program in his position as an instructor at the Royal Danish Army Officers’ Academy. The sum...

  20. Patofysiologiske aspekter ved statiners diabetogene effekt

    DEFF Research Database (Denmark)

    Pilemann-Lyberg, Sascha; Solis, Anette Bratt; Gæde, Peter

    2014-01-01

    Statins are potent inhibitors of cholesterol biosynthesis. Statins are beneficial in the primary and secondary prevention of coronary heart disease. Recent studies indicate that there is an association between statin use and the development of new-onset diabetes mellitus. This article reviews the...

  1. Effektive belysningsanlæg i storrumskontorer

    DEFF Research Database (Denmark)

    Traberg-Borup, Steen; Clausen, Vibeke

    Formålet med rapporten er at give den projekterende et indblik i og en forståelse for den lange række af problemer, der kan og vil opstå i forbindelse med projekteringen af et nyt belysningsanlæg eller renovering af et eksisterende. For at relatere teori til praksis har to paneler af sagkyndige p...

  2. Usikker effekt af influenzavaccination af raske voksne

    DEFF Research Database (Denmark)

    Pedersen, Louise Ørnskov; Lund, Katrine Bak; Nielsen, Tine Jepsen

    2012-01-01

    At some Danish workplaces, healthy employees are offered an influenza vaccination, although vaccination has not been proven to have a protective effect on healthy adults. This article gives an overview of the effect of influenza vaccination on healthy adults based on the results from the Cochrane...... review "Vaccines for preventing influenza in healthy adults" and new studies in the field of interest. These studies show a limited effect on influenza, influenza-like illness, lost workdays, physician visits and days of illness....

  3. Der Placebo-Effekt in biosemiotischer Sicht.

    Science.gov (United States)

    Schönbächler

    1998-01-01

    Placebo from a Biosemiotic Point of View The rise and success of modern science, first in physics, later in medicine, was based on a mechanic linear model of causality. Its only category of explanation of natural processes is the mechanical machine. As human beings using and processing signs we cannot recognize ourselves in this reductionistic model. As all living creatures we perceive, interpret and answer the stimuli of the environment. To explain the behaviour of organisms we need a semiotic-circular causality. Semiotics, the study of signs, can be subdivided in semantics, the theory of meaning of signs, in syntax, the theory of the forms and the arrangement of signs, and in pragmatics, the theory of the contextual rules of communication. Semiotics is not exclusively concerned with language, but helps as so-called biosemiotics also to explain the network of communication of a living organism. The 'Denkstil' of established pharmacology is likewise restricted to mechanistic causality. One of the consequences is the fact that theplacebo effect is defined as 'non-specific' or 'non-characteristic'. Such negative definitions exclude concrete questions of investigation. We have to accept a biosemiotic view in pharmacology, to see drugs as signs consisting of a physical vehicle equipped with meaning. The therapy with drugs must be seen in a broader treatment context investigated by pharmacopragmatics. The semiotic expansion of pharmacology does not invalidate the achievements of classic pharmacology, but elucidates in addition a view of the pragmatic components and makes the scientific integration of the placebophenomenon into drug therapy possible. The placebo effect loses its inconsistency.

  4. Effects of the ecological tax reform on the national economy. Vol. II of the final report of the project 'Quantification of the effects of the ecological tax reform on the environment, the labour market, and innovation'; Gesamtwirtschaftliche Effekte der oekologischen Steuerreform. Bd. II des Endberichts fuer das Vorhaben: ''Quantifizierung der Effekte der Oekologischen Steuerreform auf Umwelt, Beschaeftigung und Innovation''

    Energy Technology Data Exchange (ETDEWEB)

    Kohlhaas, Michael

    2005-08-15

    die Rahmenbedingungen jedoch erheblich veraendert. So wurden einige Steuersaetze erhoeht und die Sonderregelungen modifiziert, die Teilen der Wirtschaft gewaehrt werden, um die Belastungen durch die OeSR zu begrenzen. Die Untersuchung erfolgt auf der Basis der im ersten Teil dieses Teilprojekts berechneten Daten zur Be- und Entlastung einzelner Wirtschaftsbereiche und unter Beruecksichtigung einzel- und gesamtwirtschaftlicher Anpassungsreaktionen. Fuer die Berechnung wird LEAN eingesetzt, ein sequentiell-dynamisches berechenbares allgemeines Gleichgewichtsmodell mit 13 Sektoren und (in der fuer dieses Projekt verwendeten Version) zwei Regionen (Deutschland und die uebrige EU15). Fuenf der Sektoren entsprechen den Energietraegern Steinkohle, Braunkohle, Mineraloel, Gas und Elektrizitaet. Der Elektrizitaetssektor unterscheidet sechs verschiedene Erzeugungstechnologien (Steinkohle, Braunkohle, Oel, Gas, Kernenergie und regenerierbare Energien). Die Modellsimulationen bestaetigen im Wesentlichen die Ergebnisse von Bach et al. (2001): Die OeSR in Deutschland ist geeignet, einen substanziellen Beitrag zur Verminderung der CO2-Emissionen herbeizufuehren, ohne die wirtschaftliche Entwicklung zu beeintraechtigen. Gleichzeitig kann ueber die Senkung der Rentenversicherungsbeitraege ein Anreiz gegeben werden, zusaetzliche Arbeitsplaetze zu schaffen. Ob und in welchem Umfang dies gelingt, haengt in dem Modell davon ab, wie stark die Lohnforderungen auf eine Veraenderung der Beschaeftigungssituation reagieren. Darueber hinaus wurde untersucht, wie sich die Neuregelung der Sonderregelungen fuer die Wirtschaft auswirkt, deren Ziel es war, oekologische Anreize zur effizienten Energienutzung zu verstaerken, ohne die internationale Wettbewerbssituation der Unternehmen zu gefaehrden. Nach den Modellrechnungen gehen die Effekte zwar in die richtige Richtung, sind quantitativ aber sehr gering. Dazu traegt vor allem bei, dass fuer einen Teil der Unternehmen durch die Neugestaltung der

  5. Soft Tissue Sarcoma

    Science.gov (United States)

    ... muscles, tendons, fat, and blood vessels. Soft tissue sarcoma is a cancer of these soft tissues. There ... have certain genetic diseases. Doctors diagnose soft tissue sarcomas with a biopsy. Treatments include surgery to remove ...

  6. Sacroiliitis in children with spondyloarthropathy: therapeutic effect of CT-guided intra-articular corticosteroid injection; Sakroiliitis bei Kinder mit Spondylarthropathie: Therapeutischer Effekt der CT-gestuetzten intraartikulaeren Kortikosteroid-Injektionen

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, T.; Hermann, K.G.A.; Diekmann, F.; Hamm, B. [Humboldt-Universitaet, Berlin (Germany). Universitaetsklinikum Charite, Inst. fuer Radiologie; Biedermann, T. [HELIOS Klinikum Berlin (Germany). II. Klinik fuer Kinderheilkunde und Jugendmedizin, Abt. Kinderrheumatologie; Braun, J. [Rheumazentrum Ruhrgebiet, St. Josefs-Krankenhaus (Germany); Bollow, M. [Augusta-Krankenhaus, Bochum (Germany). Inst. fuer Radiologie

    2003-06-01

    . The follow-up dynamic MRI (0.1 mmol/kg body weight) during therapy showed a statistically significant lower contrast-enhancement in both groups (group 1: 117{+-}43% versus 38{+-}24%, p<0.05; group 2: 127{+-}59% versus 38{+-}22%, p<0.05). One third of the patients of group 2 showed progression of joint destruction despite absence of subjective complaints. (orig.) [German] Ziel: Prospektive Pruefung des therapeutischen Effektes der CT-gesteuerten intraartikulaeren Kortikosteroid-Injektion entzuendlicher Sakroiliakalgelenke (SIG) bei Kindern mit juveniler Spondylarthropathie (jSpA) im Vergleich zur konventionellen Therapie mit nichtsteroidalen Antirheumatika (NSAR) sowie Bestimmung der Wertigkeit der Magnetresonanztomographie (MRT) bei der Indikationsstellung und der Therapieverlaufskontrolle. Material und Methode: Bei 89 Kindern mit bekannter jSpA wurden mittels dynamischer MRT uni- oder bilaterale Sakroiliitiden diagnostiziert. Bei allen 89 Patienten wurde daraufhin eine Therapie mit NSAR eingeleitet bzw. bereits bestehende Therapien fortgesetzt. Vier Wochen nach der diagnostischen MRT wurden zwei Gruppen definiert: 33 Patienten mit klinischem Response auf NSAR (Gruppe 1) und 56 Nonresponder (Gruppe 2). Die Patienten der Gruppe 2 wurden unter Belassung der NSAR zusaetzlich einer CT-gestuetzten (Low-Dose-Technik) intraartikulaeren Kortikosteroid-Injektion zugefuehrt, wobei insgesamt 83 SIG punktiert und infiltriert wurden (27 bilateral, 29 unilateral). Die Indikationsstellung zur Intervention beruhte auf der zuvor MR-tomographisch gesicherten Entzuendungsaktivitaet. Klinische Therapieverlaufskontrollen erfolgten in 8- bis 12-woechigen Intervallen ueber einen Zeitraum von 20 Monaten. MRT-Verlaufskontrollen wurden bei allen 56 Kindern der Gruppe 2 und bei 15 von 33 Kindern der Gruppe 1 in einem Zeitraum von 8{+-}4 Monaten nach der Erstuntersuchung durchgefuehrt. Ergebnisse: Ingesamt 87,5% der komplikationslos punktierten Kinder der Gruppe 2 (Standardtherapie

  7. Impact of numerical information on risk knowledge regarding human papillomavirus (HPV vaccination among schoolgirls: a randomised controlled trial [Effekt von Zahlenangaben auf das Risikowissen von Schülerinnen zur Humanen Papillomavirus (HPV-Impfung: eine randomisiert-kontrollierte Studie

    Directory of Open Access Journals (Sweden)

    Steckelberg, Anke

    2013-10-01

    recipients: Mean value of risk knowledge score (0–5 points: 4.6±1.0 vs. 2.6±1.2 (mean difference 2.0 (95% CI 1.6–2.4; (P[german] Einführung: In Deutschland wurde die Implementierung der Humanen Papillomavirus (HPV-Impfung für 12–17-jährige Mädchen von diversen Kampagnen begleitet. Evidenz-basierte Informationen, die Zahlenangaben beinhalten, wurden nicht zur Verfügung gestellt. Stattdessen führten die Standardinformationen zu einer Überschätzung des Krebsrisikos und den Effekten der HPV-Impfung. Das Vertrauen in die Fähigkeit von Kindern mit Risiken umzugehen ist gering, insbesondere wenn es sich um sozial benachteiligte Schüler handelt. Das Ziel dieser Studie ist ein Vergleich der Effekte eines Standard-Flyers mit einem Informationsflyer, der Zahlenangaben beinhaltet, hinsichtlich des Risikowissens über die HPV-Impfung bei Schülerinnen. Methoden: Randomisiert-kontrollierte Kurzzeitstudie. Es wurden alle 108 Schülerinnen aus sieben Schulklassen auf die Teilnahme angesprochen und 105 stimmten zu. Die Teilnehmerinnen waren Berufsfachschülerinnen, die den Abschluss der 10. Klasse anstrebten und zur Zielgruppe für eine HPV-Impfung gehörten. Die Kontrollgruppe wurde gebeten, den Standardflyer des Nationalen Netzwerks Frauen und Gesundheit zu lesen. Die Interventionsgruppe erhielt den gleichen Flyer, der jedoch mit numerischen Informationen zum Krebsrisiko und zu den angenommenen Effekten der HPV-Impfung auf die Krebsprävention ergänzt worden war. Als Basischarakteristika wurden Alter, Impfstatus, Einstellung zur HPV-Impfung und Aspekte bezüglich des Migrationshintergrunds erhoben. Der primäre Endpunkt war Risikowissen. Die Fragebogenerhebungen erfolgten unter experimentellen Bedingungen. Die individuelle Randomisierung, die Teilnehmerinnen und die intention-to-treat Datenanalyse waren verblindet. Die Studie wurde vom Ministerium für Bildung und Kultur des Landes Schleswig-Holstein und der Ethikkommission der Hamburger Ärztekammer genehmigt

  8. Tissue bionics: examples in biomimetic tissue engineering

    International Nuclear Information System (INIS)

    Green, David W

    2008-01-01

    Many important lessons can be learnt from the study of biological form and the functional design of organisms as design criteria for the development of tissue engineering products. This merging of biomimetics and regenerative medicine is termed 'tissue bionics'. Clinically useful analogues can be generated by appropriating, modifying and mimicking structures from a diversity of natural biomatrices ranging from marine plankton shells to sea urchin spines. Methods in biomimetic materials chemistry can also be used to fabricate tissue engineering scaffolds with added functional utility that promise human tissues fit for the clinic

  9. Tissue bionics: examples in biomimetic tissue engineering.

    Science.gov (United States)

    Green, David W

    2008-09-01

    Many important lessons can be learnt from the study of biological form and the functional design of organisms as design criteria for the development of tissue engineering products. This merging of biomimetics and regenerative medicine is termed 'tissue bionics'. Clinically useful analogues can be generated by appropriating, modifying and mimicking structures from a diversity of natural biomatrices ranging from marine plankton shells to sea urchin spines. Methods in biomimetic materials chemistry can also be used to fabricate tissue engineering scaffolds with added functional utility that promise human tissues fit for the clinic.

  10. Tissue bionics: examples in biomimetic tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Green, David W [Bone and Joint Research Group, Developmental Origins of Health and Disease, General Hospital, University of Southampton, SO16 6YD (United Kingdom)], E-mail: Hindoostuart@googlemail.com

    2008-09-01

    Many important lessons can be learnt from the study of biological form and the functional design of organisms as design criteria for the development of tissue engineering products. This merging of biomimetics and regenerative medicine is termed 'tissue bionics'. Clinically useful analogues can be generated by appropriating, modifying and mimicking structures from a diversity of natural biomatrices ranging from marine plankton shells to sea urchin spines. Methods in biomimetic materials chemistry can also be used to fabricate tissue engineering scaffolds with added functional utility that promise human tissues fit for the clinic.

  11. FRD tissue archive

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The fishery genetics tissue collection has over 80,000 tissues stored in 95% ethanol representing fishes and invertebrates collected globally but with a focus on the...

  12. Plant tissue culture techniques

    Directory of Open Access Journals (Sweden)

    Rolf Dieter Illg

    1991-01-01

    Full Text Available Plant cell and tissue culture in a simple fashion refers to techniques which utilize either single plant cells, groups of unorganized cells (callus or organized tissues or organs put in culture, under controlled sterile conditions.

  13. Breast Cancer Tissue Repository

    National Research Council Canada - National Science Library

    Iglehart, J

    1997-01-01

    The Breast Tissue Repository at Duke enters its fourth year of finding. The purpose of the Repository at Duke is to provide substantial quantities of frozen tissue for explorative molecular studies...

  14. Vascularization Tissue Engineering

    NARCIS (Netherlands)

    Rouwkema, Jeroen; Rivron, N.C.; van Blitterswijk, Clemens

    2008-01-01

    Tissue engineering has been an active field of research for several decades now. However, the amount of clinical applications in the field of tissue engineering is still limited. One of the current limitations of tissue engineering is its inability to provide sufficient blood supply in the initial

  15. Plant Tissue Culture

    Indian Academy of Sciences (India)

    Admin

    The success of plant biotechnology relies on the fundamental techniques of plant tissue culture. Understanding basic biol- ogy of plants is a prerequisite for proper utilization of the plant system or parts thereof. Plant tissue culture helps in providing a basic understanding of physical and chemical requirements of cell, tissue, ...

  16. Tissue engineering of reproductive tissues and organs.

    Science.gov (United States)

    Atala, Anthony

    2012-07-01

    Regenerative medicine and tissue engineering technology may soon offer new hope for patients with serious injuries and end-stage reproductive organ failure. Scientists are now applying the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that can restore and maintain normal function in diseased and injured reproductive tissues. In addition, the stem cell field is advancing, and new discoveries in this field will lead to new therapeutic strategies. For example, newly discovered types of stem cells have been retrieved from uterine tissues such as amniotic fluid and placental stem cells. The process of therapeutic cloning and the creation of induced pluripotent cells provide still other potential sources of stem cells for cell-based tissue engineering applications. Although stem cells are still in the research phase, some therapies arising from tissue engineering endeavors that make use of autologous adult cells have already entered the clinic. This article discusses these tissue engineering strategies for various organs in the male and female reproductive tract. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  17. Cell and Tissue Engineering

    CERN Document Server

    2012-01-01

    “Cell and Tissue Engineering” introduces the principles and new approaches in cell and tissue engineering. It includes both the fundamentals and the current trends in cell and tissue engineering, in a way useful both to a novice and an expert in the field. The book is composed of 13 chapters all of which are written by the leading experts. It is organized to gradually assemble an insight in cell and tissue function starting form a molecular nano-level, extending to a cellular micro-level and finishing at the tissue macro-level. In specific, biological, physiological, biophysical, biochemical, medical, and engineering aspects are covered from the standpoint of the development of functional substitutes of biological tissues for potential clinical use. Topics in the area of cell engineering include cell membrane biophysics, structure and function of the cytoskeleton, cell-extracellular matrix interactions, and mechanotransduction. In the area of tissue engineering the focus is on the in vitro cultivation of ...

  18. Engineering functional bladder tissues.

    Science.gov (United States)

    Horst, Maya; Madduri, Srinivas; Gobet, Rita; Sulser, Tullio; Milleret, Vinzent; Hall, Heike; Atala, Anthony; Eberli, Daniel

    2013-07-01

    End stage bladder disease can seriously affect patient quality of life and often requires surgical reconstruction with bowel tissue, which is associated with numerous complications. Bioengineering of functional bladder tissue using tissue-engineering techniques could provide new functional tissues for reconstruction. In this review, we discuss the current state of this field and address different approaches to enable physiologic voiding in engineered bladder tissues in the near future. In a collaborative effort, we gathered researchers from four institutions to discuss the current state of functional bladder engineering. A MEDLINE® and PubMed® search was conducted for articles related to tissue engineering of the bladder, with special focus on the cells and biomaterials employed as well as the microenvironment, vascularisation and innervation strategies used. Over the last decade, advances in tissue engineering technology have laid the groundwork for the development of a biological substitute for bladder tissue that can support storage of urine and restore physiologic voiding. Although many researchers have been able to demonstrate the formation of engineered tissue with a structure similar to that of native bladder tissue, restoration of physiologic voiding using these constructs has never been demonstrated. The main issues hindering the development of larger contractile tissues that allow physiologic voiding include the development of correct muscle alignment, proper innervation and vascularization. Tissue engineering of a construct that will support the contractile properties that allow physiologic voiding is a complex process. The combination of smart scaffolds with controlled topography, the ability to deliver multiple trophic factors and an optimal cell source will allow for the engineering of functional bladder tissues in the near future. Copyright © 2012 John Wiley & Sons, Ltd.

  19. DNA from keratinous tissue

    DEFF Research Database (Denmark)

    Bengtsson, Camilla F.; Olsen, Maja E.; Brandt, Luise Ørsted

    2011-01-01

    Keratinous tissues such as nail, hair, horn, scales and feather have been used as a source of DNA for over 20 years. Particular benefits of such tissues include the ease with which they can be sampled, the relative stability of DNA in such tissues once sampled, and, in the context of ancient...... genetic analyses, the fact that sampling generally causes minimal visual damage to valuable specimens. Even when freshly sampled, however, the DNA quantity and quality in the fully keratinized parts of such tissues is extremely poor in comparison to other tissues such as blood and muscle – although little...... systematic research has been undertaken to characterize how such degradation may relate to sample source. In this review paper we present the current understanding of the quality and limitations of DNA in two key keratinous tissues, nail and hair. The findings indicate that although some fragments of nuclear...

  20. Tissue engineering in dentistry.

    Science.gov (United States)

    Abou Neel, Ensanya Ali; Chrzanowski, Wojciech; Salih, Vehid M; Kim, Hae-Won; Knowles, Jonathan C

    2014-08-01

    of this review is to inform practitioners with the most updated information on tissue engineering and its potential applications in dentistry. The authors used "PUBMED" to find relevant literature written in English and published from the beginning of tissue engineering until today. A combination of keywords was used as the search terms e.g., "tissue engineering", "approaches", "strategies" "dentistry", "dental stem cells", "dentino-pulp complex", "guided tissue regeneration", "whole tooth", "TMJ", "condyle", "salivary glands", and "oral mucosa". Abstracts and full text articles were used to identify causes of craniofacial tissue loss, different approaches for craniofacial reconstructions, how the tissue engineering emerges, different strategies of tissue engineering, biomaterials employed for this purpose, the major attempts to engineer different dental structures, finally challenges and future of tissue engineering in dentistry. Only those articles that dealt with the tissue engineering in dentistry were selected. There have been a recent surge in guided tissue engineering methods to manage periodontal diseases beyond the traditional approaches. However, the predictable reconstruction of the innate organisation and function of whole teeth as well as their periodontal structures remains challenging. Despite some limited progress and minor successes, there remain distinct and important challenges in the development of reproducible and clinically safe approaches for oral tissue repair and regeneration. Clearly, there is a convincing body of evidence which confirms the need for this type of treatment, and public health data worldwide indicates a more than adequate patient resource. The future of these therapies involving more biological approaches and the use of dental tissue stem cells is promising and advancing. Also there may be a significant interest of their application and wider potential to treat disorders beyond the craniofacial region. Considering the

  1. Synovial tissue research

    DEFF Research Database (Denmark)

    Orr, Carl; Sousa, Elsa; Boyle, David L

    2017-01-01

    The synovium is the major target tissue of inflammatory arthritides such as rheumatoid arthritis. The study of synovial tissue has advanced considerably throughout the past few decades from arthroplasty and blind needle biopsy to the use of arthroscopic and ultrasonographic technologies that enab...

  2. Soft Tissue Sarcoma

    Science.gov (United States)

    ... removed Causes In most cases, it's not clear what causes soft tissue sarcoma. In general, cancer occurs when cells develop ... of cell that develops the genetic mutation determines what type of soft tissue sarcoma you have. For example, angiosarcoma begins in ...

  3. Tissue engineered aortic valve

    OpenAIRE

    Dohmen, P M

    2012-01-01

    Several prostheses are available to replace degenerative diseased aortic valves with unique advantages and disadvantages. Bioprotheses show excellent hemodynamic behavior and low risk of thromboembolic complications, but are limited by tissue deterioration. Mechanical heart valves have extended durability, but permanent anticoagulation is mandatory. Tissue engineering created a new generation heart valve, which overcome limitations of biological and mechanical heart valves due to remodelling,...

  4. Nonfreezing Tissue Injuries

    Science.gov (United States)

    ... News) Small Study Uncovers Brain Disease in Former Soccer Players (Video) Anterior Cruciate Ligament (Video) Resisted Finger Abduction and Extension With Putty Additional Content Medical News Nonfreezing Tissue Injuries (Chilblains [Pernio]; Frostnip; Immersion Foot [Trench Foot]) By ...

  5. Skeletal muscle connective tissue

    DEFF Research Database (Denmark)

    Brüggemann, Dagmar Adeline

      The connective tissue content of skeletal muscle is believed to be the major factor responsible for defining the eating quality of different meat cuts, although attempts to correlate quantifications based on traditional histological methods have not as yet been able to prove this relation...... that collagen plays a significant role in determining the tenderness of meat. What are we missing? Therefore, fundamental aspects of connective tissue research have been the centre of attention throughout this thesis. A holistic view has been applied, glancing at this complex tissue which has many facets...... in this thesis that alpha-ketoglutarate, a tricarboxylic acid cycle metabolite, has the potential to control the metabolism of this particular tissue. Finally, a new microscopic method is introduced which allows the study of thermal denaturation of fibrillar collagen and myofibers in real time without any label...

  6. Breast reconstruction - natural tissue

    Science.gov (United States)

    ... After a mastectomy , some women choose to have cosmetic surgery to remake their breast. This type of surgery ... cancer - breast reconstruction with natural tissue Patient Instructions Cosmetic breast surgery - discharge Mastectomy and breast reconstruction - what to ask ...

  7. Skeletal muscle connective tissue

    DEFF Research Database (Denmark)

    Brüggemann, Dagmar Adeline

    that collagen plays a significant role in determining the tenderness of meat. What are we missing? Therefore, fundamental aspects of connective tissue research have been the centre of attention throughout this thesis. A holistic view has been applied, glancing at this complex tissue which has many facets......  The connective tissue content of skeletal muscle is believed to be the major factor responsible for defining the eating quality of different meat cuts, although attempts to correlate quantifications based on traditional histological methods have not as yet been able to prove this relation....... Collagen, being the major protein in connective tissue, has been extensively investigated with regard to its relation to meat tenderness, but the results have been rather conflicting. Meat from older animals is tougher than that from younger animals, and changes in the properties of the collagen due...

  8. [Tissue toxicity of antiseptics].

    Science.gov (United States)

    Kalteis, T; Lüring, C; Schaumburger, J; Perlick, L; Bäthis, H; Grifka, J

    2003-01-01

    Local antiseptics are used for desinfection of skin and for lavage of wounds. The aim of this study was to determine the tissue toxicity of different antiseptics and to measure the irritation score (IS) and the irritation threshold (IT) for each substance. The tissue compatibilities of Dibromol, Kodan, Jodobac, Octenisept, Lavasept 0.2 %, hydrogen peroxide, chlorhexidindigluconate 0.5 % and 2-propanol 60 % were evaluated in the in vivo hens eggs chorion-allantoic membrane test (HET-CAM). We found the most severe tissue toxicity for chlorhexidin digluconate 0.5 % (IS 20) and Kodan (IS 18). Irritating values were found for Dibromol (IS 14), Octenisept (IS 14) and 2-propanol 60 % (IS 13). Moderate vascular injuries were caused by Jodobac (IS 2). In the HET-CAM test Lavasept 0.2 % (IS 0) and hydrogen peroxide (IS 0) showed no tissue toxicity. Our results show that some of the tested antiseptics might cause severe vascular injuries as a sign of tissue toxicity. The tissue compatibility of Lavasept 0.2 % and hydrogen peroxide is much better than the compatibility of the other tested substances. With focus on the literature and our results, Lavasept 0.2 % can be recommended as the local antiseptic of choice.

  9. Autopsy Tissue Program

    International Nuclear Information System (INIS)

    Fox, T.; Tietjen, G.

    1979-01-01

    The Autopsy Tissue Program was begun in 1960. To date, tissues on 900 or more persons in 7 geographic regions have been collected and analyzed for plutonium content. The tissues generally consist of lung, liver, kidney, lymph, bone, and gonadal tissue for each individual. The original objective of the program was to determine the level of plutonium in human tissues due solely to fall-out from weapons testing. The baseline thus established was to be used to evaluate future changes. From the first, this program was beset with chemical and statistical difficulties. Many factors whose effects were not recognized and not planned for were found later to be important. Privacy and ethical considerations hindered the gathering of adequate data. Since the chemists were looking for amounts of plutonium very close to background, possible contamination was a very real problem. Widely used chemical techniques introduced a host of statistical problems. The difficulties encountered touch on areas common to large data sets, unusual outlier detection methods, minimum detection limits, problems with Aliquot sizes, and time-trends in the data. The conclusions point out areas to which the biologists will have to devote much more careful attention than was believed

  10. Morphology of urethral tissues

    Science.gov (United States)

    Müller, Bert; Schulz, Georg; Herzen, Julia; Mushkolaj, Shpend; Bormann, Therese; Beckmann, Felix; Püschel, Klaus

    2010-09-01

    Micro computed tomography has been developed to a powerful technique for the characterization of hard and soft human and animal tissues. Soft tissues including the urethra, however, are difficult to be analyzed, since the microstructures of interest exhibit X-ray absorption values very similar to the surroundings. Selective staining using highly absorbing species is a widely used approach, but associated with significant tissue modification. Alternatively, one can suitably embed the soft tissue, which requires the exchange of water. Therefore, the more recently developed phase contrast modes providing much better contrast of low X-ray absorbing species are especially accommodating in soft tissue characterization. The present communication deals with the morphological characterization of sheep, pig and human urethras on the micrometer scale taking advantage of micro computed tomography in absorption and phase contrast modes. The performance of grating-based tomography is demonstrated for freshly explanted male and female urethras in saline solution. The micro-morphology of the urethra is important to understand how the muscles close the urethra to reach continence. As the number of incontinent patients is steadily increasing, the function under static and, more important, under stress conditions has to be uncovered for the realization of artificial urinary sphincters, which needs sophisticated, biologically inspired concepts to become nature analogue.

  11. Neural tissue-spheres

    DEFF Research Database (Denmark)

    Andersen, Rikke K; Johansen, Mathias; Blaabjerg, Morten

    2007-01-01

    maintained their neurogenic potential throughout 77 days of propagation, while the ability of anterior NTS to generate neurons severely declined from day 40. The present procedure describes isolation and long-term expansion of forebrain SVZ tissue with potential preservation of the endogenous cellular......By combining new and established protocols we have developed a procedure for isolation and propagation of neural precursor cells from the forebrain subventricular zone (SVZ) of newborn rats. Small tissue blocks of the SVZ were dissected and propagated en bloc as free-floating neural tissue...... derived from three rostro-caudal levels of the lateral ventricles (anterior, intermediate and posterior) and propagated separately. Explants from all three levels produced proliferating NTS, but "anterior" NTS in general grew to smaller sizes than "intermediate" and "posterior" NTS. Posterior NTS moreover...

  12. Biomechanics of brain tissue.

    Science.gov (United States)

    Prevost, Thibault P; Balakrishnan, Asha; Suresh, Subra; Socrate, Simona

    2011-01-01

    The dynamic behavior of porcine brain tissue, obtained from a series of in vitro observations and experiments, is analyzed and described here with the aid of a large strain, nonlinear, viscoelastic constitutive model. Mixed gray and white matter samples excised from the superior cortex were tested in unconfined uniaxial compression within 15h post mortem. The test sequence consisted of three successive load-unload segments at strain rates of 1, 0.1 and 0.01 s⁻¹, followed by stress relaxation (n=25). The volumetric compliance of the tissue was assessed for a subset of specimens (n=7) using video extensometry techniques. The tissue response exhibited moderate compressibility, substantial nonlinearity, hysteresis, conditioning and rate dependence. A large strain kinematics nonlinear viscoelastic model was developed to account for the essential features of the tissue response over the entire deformation history. The corresponding material parameters were obtained by fitting the model to the measured conditioned response (axial and volumetric) via a numerical optimization scheme. The model successfully captures the observed complexities of the material response in loading, unloading and relaxation over the entire range of strain rates. The accuracy of the model was further verified by comparing model predictions with the tissue response in unconfined compression at higher strain rate (10 s⁻¹) and with literature data in uniaxial tension. The proposed constitutive framework was also found to be adequate to model the loading response of brain tissue in uniaxial compression over a wider range of strain rates (0.01-3000 s⁻¹), thereby providing a valuable tool for simulations of dynamic transients (impact, blast/shock wave propagation) leading to traumatic brain injury. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  13. Soft Tissue Extramedullary Plasmacytoma

    Directory of Open Access Journals (Sweden)

    Fernando Ruiz Santiago

    2010-01-01

    Full Text Available We present the uncommon case of a subcutaneous fascia-based extramedullary plasmacytoma in the leg, which was confirmed by the pathology report and followed up until its remission. We report the differential diagnosis with other more common soft tissue masses. Imaging findings are nonspecific but are important to determine the tumour extension and to plan the biopsy.

  14. Tissue culture and neurotoxicology

    NARCIS (Netherlands)

    Hooisma, J.

    1982-01-01

    Application of tissue culture in neurotoxicology may serve two purposes. First, they may be used to unravel the mechanism of action of neurotoxic compounds and secondly, they may be used for the screening of neurotoxic agents. Studies belonging to the first group can be subdivided into those aiming

  15. Tissue Engineering Initiative

    Science.gov (United States)

    2002-08-01

    connective tissue, the extracellular matrix of hypertrophic cartilage and the lacunae of osteocytes resembling cortical bone [54]. In the long shaft of...cells. Canadian Journal of Cardiology 12(3): 231-236, 1996. 9. Oakes BW, Batty AC, Handley CJ, Sandberg LB. The synthesis of elastin, collagen, and

  16. Plant Tissue Culture

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 8. Plant Tissue Culture - Historical Developments and Applied Aspects. H R Dagla. General Article Volume 17 Issue 8 August 2012 pp 759-767. Fulltext. Click here to view fulltext PDF. Permanent link:

  17. Soft tissue mixed tumor

    Directory of Open Access Journals (Sweden)

    Eiichi Hiraishi

    2009-12-01

    Full Text Available Mixed tumors are relatively common in the skin and salivary glands, but extremely rare in soft tissues, often resulting in diagnostic problems. The occurrence of these tumors in the hand is especially limited. In this article we report the clinical, radiological, and histological features of a mixed tumor of the hypothenar region of the right hand.

  18. Plant Tissue Culture

    Indian Academy of Sciences (India)

    Admin

    closely linked with the discovery and characterization of plant hormones, and has facilitated our understanding of plant growth and development. Furthermore, the ability to grow plant cells and tissues in culture and to control their development forms the basis of many practical applications in agriculture, horticulture indus-.

  19. Plant Tissue Culture Studies.

    Science.gov (United States)

    Smith, Robert Alan

    Plant tissue culture has developed into a valid botanical discipline and is considered a key area of biotechnology, but it has not been a key component of the science curriculum because of the expensive and technical nature of research in this area. This manual presents a number of activities that are relatively easy to prepare and perform. The…

  20. Mixed Connective Tissue Disease

    Science.gov (United States)

    ... complicated. Early signs and symptoms often involve the hands. Fingers might swell like sausages, and the fingertips become white and numb. In later stages, some organs — such as the lungs, heart and kidneys — may be affected. There's no cure for mixed connective tissue disease. The signs and ...

  1. Joint and Soft Tissue Injections

    Science.gov (United States)

    ... Injections Joint and Soft Tissue Injections Share Print What is a joint and soft tissue injection? Joint and soft tissue injections are shots ... many injections do I need and how often? What restrictions do I have after an ... tissue injection, treatment April 1, 2004 Copyright © American Academy ...

  2. Gram stain of tissue biopsy

    Science.gov (United States)

    ... suspected. Normal Results Whether there are bacteria, and what type there are, depends on the tissue being biopsied. Some tissues in the body are ... about the meaning of your specific test results. What Abnormal Results Mean ... results usually mean there is an infection in the tissue. More tests, such as culturing the tissue that ...

  3. Nicotine and periodontal tissues

    Directory of Open Access Journals (Sweden)

    Malhotra Ranjan

    2010-01-01

    Full Text Available Tobacco use has been recognized to be a significant risk factor for the development and progression of periodontal disease. Its use is associated with increased pocket depths, loss of periodontal attachment, alveolar bone and a higher rate of tooth loss. Nicotine, a major component and most pharmacologically active agent in tobacco is likely to be a significant contributing factor for the exacerbation of periodontal diseases. Available literature suggests that nicotine affects gingival blood flow, cytokine production, neutrophil and other immune cell function; connective tissue turnover, which can be the possible mechanisms responsible for overall effects of tobacco on periodontal tissues. Inclusion of tobacco cessation as a part of periodontal therapy encourages dental professionals to become more active in tobacco cessation counseling. This will have far reaching positive effects on our patients′ oral and general health.

  4. Subcutaneous adipose tissue classification

    Directory of Open Access Journals (Sweden)

    A. Sbarbati

    2010-11-01

    Full Text Available The developments in the technologies based on the use of autologous adipose tissue attracted attention to minor depots as possible sampling areas. Some of those depots have never been studied in detail. The present study was performed on subcutaneous adipose depots sampled in different areas with the aim of explaining their morphology, particularly as far as regards stem niches. The results demonstrated that three different types of white adipose tissue (WAT can be differentiated on the basis of structural and ultrastructural features: deposit WAT (dWAT, structural WAT (sWAT and fibrous WAT (fWAT. dWAT can be found essentially in large fatty depots in the abdominal area (periumbilical. In the dWAT, cells are tightly packed and linked by a weak net of isolated collagen fibers. Collagenic components are very poor, cells are large and few blood vessels are present. The deep portion appears more fibrous then the superficial one. The microcirculation is formed by thin walled capillaries with rare stem niches. Reinforcement pericyte elements are rarely evident. The sWAT is more stromal; it is located in some areas in the limbs and in the hips. The stroma is fairly well represented, with a good vascularity and adequate staminality. Cells are wrapped by a basket of collagen fibers. The fatty depots of the knees and of the trochanteric areas have quite loose meshes. The fWAT has a noteworthy fibrous component and can be found in areas where a severe mechanic stress occurs. Adipocytes have an individual thick fibrous shell. In conclusion, the present study demonstrates evident differences among subcutaneous WAT deposits, thus suggesting that in regenerative procedures based on autologous adipose tissues the sampling area should not be randomly chosen, but it should be oriented by evidence based evaluations. The structural peculiarities of the sWAT, and particularly of its microcirculation, suggest that it could represent a privileged source for

  5. The plant tissue culture

    International Nuclear Information System (INIS)

    Crocomo, O.J.; Sharp, W.R.

    1973-01-01

    Progress in the field of plant tissue culture at the Plant Biochemistry Sector, Centro de Energia na Agricultura (CENA), Piracicaba, S.P., Brazil, pertains to the simplification of development in 'Phaseolus vulgaris' by dividing the organism into its component organs, tissues, and cells and the maintenance of these components on defined culture media 'in vitro'. This achievement has set the stage for probing the basis for the stability of the differentiated states and/or the reentry of mature differentiated cells into the mitotic cell cycle and their subsequent redifferentiation. Data from such studies at the cytological and biochemical level have been invaluable in the elucidation of the control mechanisms responsible for expression of the cellular phenotype. Unlimited possibilities exist for the application of tissue culture in the vegetative propagation of 'Phaseolus' and other important cultivars in providing genocopies or a large scale and/or readily obtaining plantlets from haploid cell lines or from protoplast (wall-less cells) hybridization products following genetic manipulation. These tools are being applied in this laboratory for the development and selection of high protein synthesizing 'Phaseolus' cultivars

  6. Necrotizing Soft Tissue Infection

    Directory of Open Access Journals (Sweden)

    Sahil Aggarwal, BS

    2018-04-01

    Full Text Available History of present illness: A 71-year-old woman with a history of metastatic ovarian cancer presented with sudden onset, rapidly progressing painful rash in the genital region and lower abdominal wall. She was febrile to 103°F, heart rate was 114 beats per minute, and respiratory rate was 24 per minute. Her exam was notable for a toxic-appearing female with extensive areas of erythema, tenderness, and induration to her lower abdomen, intertriginous areas, and perineum with intermittent segments of crepitus without hemorrhagic bullae or skin breakdown. Significant findings: Computed tomography (CT of the abdominal and pelvis with intravenous (IV contrast revealed inflammatory changes, including gas and fluid collections within the ventral abdominal wall extending to the vulva, consistent with a necrotizing soft tissue infection. Discussion: Necrotizing fasciitis is a serious infection of the skin and soft tissues that requires an early diagnosis to reduce morbidity and mortality. Classified into several subtypes based on the type of microbial infection, necrotizing fasciitis can rapidly progress to septic shock or death if left untreated.1 Diagnosing necrotizing fasciitis requires a high index of suspicion based on patient risk factors, presentation, and exam findings. Definitive treatment involves prompt surgical exploration and debridement coupled with IV antibiotics.2,3 Clinical characteristics such as swelling, disproportionate pain, erythema, crepitus, and necrotic tissue should be a guide to further diagnostic tests.4 Unfortunately, lab values such as white blood cell count and lactate imaging studies have high sensitivity but low specificity, making the diagnosis of necrotizing fasciitis still largely a clinical one.4,5 CT is a reliable method to exclude the diagnosis of necrotizing soft tissue infections (sensitivity of 100%, but is only moderately reliable in correctly identifying such infections (specificity of 81%.5 Given the emergent

  7. Tissue bank: Sri Lanka

    International Nuclear Information System (INIS)

    2003-01-01

    Human degenerative diseases and congenital defects are common throughout the world. Many people suffer also from burns, fractures and nerve damage resulting from traumatic accidents and outbreaks of violence which occur all too frequently, especially in poorer countries. Far too many people are impaired for life because they have no access to treatment or simply cannot afford it. The Department of Technical Co-operation is sponsoring a programme, with technical support from the Division of Nuclear Medicine, to improve facilities at the Sri Lanka Tissue Bank. (IAEA)

  8. Microsurgical Composite Tissue Transplantation

    Science.gov (United States)

    Serafin, Donald; Georgiade, Nicholas G.

    1978-01-01

    Since 1974, 69 patients with extensive defects have undergone reconstruction by microsurgical composite tissue transplantation. Using this method, donor composite tissue is isolated on its blood supply, removed to a distant recipient site, and the continuity of blood flow re-established by microvascular anastomoses. In this series, 56 patients (81%) were completely successful. There have been eight (12%) failures, primarily in the extremities. There have been five (7%) partial successes, (i.e., a microvascular flap in which a portion was lost requiring a secondary procedure such as a split thickness graft). In those patients with a severely injured lower extremity, the failure rate was the greatest. Most of these were arterial (six of seven). These failures occurred early in the series and were thought to be related to a severely damaged recipient vasculature. This problem has been circumvented by an autogenous interpositional vein graft, permitting more mobility of flap placement. In the upper extremity, all but one case were successful. Early motion was permitted, preventing joint capsular contractures and loss of function. Twenty-three cases in the head and neck region were successful (one partial success). This included two composite rib grafts to the mandible. Prolonged delays in reconstruction following extirpation of a malignancy were avoided. A rapid return to society following complete reconstruction was ensured. Nine patients presented for reconstruction of the breast and thorax following radical mastectomy. All were successfully reconstructed with this new technique except one patient. Its many advantages include immediate reconstruction without delayed procedures and no secondary deformity of the donor site. Healthy, well vascularized tissue can now be transferred to a previously irradiated area with no tissue loss. This new method offers many advantages to older methods of reconstruction. Length of hospital stay and immobilization are reduced. The

  9. Radiation effects in normal tissues

    International Nuclear Information System (INIS)

    Trott, K.R.; Herrmann, T.; Doerr, W.

    2002-01-01

    Knowledge of radiation effects in normal tissues is fundamental for optimal planning of radiotherapy. Therefore, this book presents a review on the following aspects: General pathogenesis of acute radiation effects in normal tissues; general pathogenesis of chronic radiation effects in normal tissues; quantification of acute and chronic radiation effects in normal tissues; pathogenesis, pathology and radiation biology of various organs and organ systems. (MG) [de

  10. [Tissue engineering and osteoarthritis].

    Science.gov (United States)

    Ibarra, Clemente; Garciadiego, David; Martínez, Valentín; Velasquillo, Cristina

    2007-10-01

    Articular cartilage lesions predispose to the development of early osteoarthritis. Most current surgical techniques give rise to the formation of fibrocartilage with biochemical and biomechanical properties inferior to those or articular cartilage. Tissue engineering could offer a modern alternative to the treatment of these lesions and in this way, prevent the development of early osteoarthritis in young active patients. Different tissue engineering approaches rely on the current use of autologous chondrocytes, or the potential use of mesenchymal stem cells. Other variables rely on the type of scaffold to use such as synthetic biodegradable polymers, fibrin or collagen-derived scaffolds of different sources, bovine, porcine, rat tail, etc, in the form of gels, sponges, mesh, etc, and all of these with or without growth factors. The use of autologous chondrocytes is a reality at the present time, whether injected under a periosteum patch or seeded on collagen. However, most investigators and biotech companies are in search of onestep surgical procedures, for which reason stem cells have to be kept in mind, as well as systems that will allow arthroscopic implantation. Copyright © 2007 Elsevier España S.L Barcelona. Published by Elsevier Espana. All rights reserved.

  11. Fundamentals of bladder tissue engineering

    African Journals Online (AJOL)

    W. Mahfouz

    Stem cells;. Bladder tissue engineering;. Decellularization;. Bladder acellular matrix. Abstract. A wide range of injuries could affect the bladder and lead to eventual loss ... Tissue engineering relies upon three essential pillars; the scaffold, the cells seeded on scaffolds and lastly ..... Clinical trials in bladder tissue engineering.

  12. Banking brain tissue for research

    NARCIS (Netherlands)

    Klioueva, Natasja; Bovenberg, Jasper; Huitinga, I.

    2017-01-01

    Well-characterized human brain tissue is crucial for scientific breakthroughs in research of the human brain and brain diseases. However, the collection, characterization, management, and accessibility of brain human tissue are rather complex. Well-characterized human brain tissue is often provided

  13. Localization of IAA transporting tissue by tissue printing and autoradiography

    International Nuclear Information System (INIS)

    Mee-Rye Cha; Evans, M.L.; Hangarter, R.P.

    1991-01-01

    Tissue printing on nitrocellulose membranes provides a useful technique for visualizing anatomical details of tissue morphology of cut ends of stem segments. Basal ends of Coleus stem and corn coleoptile segments that were transporting 14 C-IAA were gently blotted onto DEAE-nitrocellulose for several minutes to allow 14 C-IAA to efflux from the tissue. Because of the anion exchange properties of DEAE-nitrocellulose the 14 C-IAA remains on the membrane at the point it leaves the transporting tissue. Autoradiography of the DEAE membrane allowed indirect visualization of the tissues preferentially involved in auxin transport. The authors observed that polar transport through the stem segments occurred primarily through or in association with vascular tissues. However, in Coleus stems, substantial amounts of the label appeared to move through the tissue by diffusion as well as by active transport

  14. Effekt og sikkerhed af kosttilskud indeholdende Q10

    DEFF Research Database (Denmark)

    Overvad, O.K; Diamant, B; Holm, L

    1997-01-01

    The literature concerning the importance of Q10 for health and disease has been reviewed. Dietary intake together with normal in vivo synthesisseems to fulfil the body's demands for Q10 in younger, healthy individuals. The importance of Q10 in general well-being has not been investigated incontro...

  15. Klinisk effekt af ranitidin ved psoriasis. Et abent prospektivt studie

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Kristensen, J K; Hansen, Ulla

    1997-01-01

    We report the results of an open, prospective study of 20 patients with moderate to severe psoriasis (median PASI score: 15.7) treated with oral ranitidine 300 mg twice daily for six months. No other medication was allowed during the study period. The median PASI score was reduced to 14.5, 9.......1 and 5.7 after one, three and six months of treatment, respectively (p study, and long-term treatment improved disease status in most patients. Eight...... patients continued therapy with ranitidine 300 mg twice daily after the study was completed. None of these patients relapsed during a follow-up period of 12-18 months. The results of the present study suggest that ranitidine may be beneficial in the treatment of some patients with psoriasis....

  16. Klinisk effekt af ranitidin ved psoriasis. Et abent prospektivt studie

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Kristensen, J K; Hansen, Ulla

    1997-01-01

    We report the results of an open, prospective study of 20 patients with moderate to severe psoriasis (median PASI score: 15.7) treated with oral ranitidine 300 mg twice daily for six months. No other medication was allowed during the study period. The median PASI score was reduced to 14.5, 9...... patients continued therapy with ranitidine 300 mg twice daily after the study was completed. None of these patients relapsed during a follow-up period of 12-18 months. The results of the present study suggest that ranitidine may be beneficial in the treatment of some patients with psoriasis....

  17. Matglede hos barn : effekter av et læringsprogram

    OpenAIRE

    Myhrer, Kristine Svartebekk

    2013-01-01

    SAMMENDRAG Bakgrunnen for denne studien var Nasjonalt råd for ernærings nye kostholdsråd for den norske befolkningen. I rådene er det anbefalt å begrense inntaket av rødt kjøtt, bearbeidet kjøtt, salt, sukker og mettet fett for å forebygge kroniske kostrelaterte sykdommer i befolkningen, slik som diabetes og overvekt. For å påvirke barns valg av mat mot et sunnere kosthold er det behov for å forstå faktorer som kan påvirke barnas valg og aksept av matvarer Formålet med masteroppgaven e...

  18. Effective utilization of fault statistics; Effektive Nutzung der Schadensstatistik

    Energy Technology Data Exchange (ETDEWEB)

    Marx, D.

    1996-09-01

    In order to improve maintenance control, it is shown how, with the help of utility value analysis, the effects of damage to plant using existing statistics can be summarized into a parameter `service value availability` characterizing the effectiveness of maintenance. (orig.) [Deutsch] Zur Verbesserung des Instandhaltungs-Controlling wird gezeigt, wie mit Hilfe der Nutzwertanalyse die Wirkungen von Schaedigungen an Anlagen unter Nutzung vorhandener Statistiken zu einer die Effektivitaet der Instandhaltung kennzeichnenden Kenngroesse der `Gebrauchswertverfuegbarkeit` zusammengefasst werden kann. (orig.)

  19. Effekt af at reducere befolkningens indtag af salt

    DEFF Research Database (Denmark)

    Lassen, Anne Dahl; Høberg Hansen, Hanne; Lykke Jeppesen, Jørgen

    2018-01-01

    Diskussionen om salt raser i medierne. Kan for meget salt – eller måske for lidt salt – være skadeligt? Blandt de fleste forskere er der bred enighed. Et højt saltindtag viser en tydelig sammenhæng med forhøjet blodtryk, som igen er forbundet med hjertekarsygdomme. Derfor vil det på befolkningsni...... befolkningsniveau være gavnligt at nedsætte mængden af salt i kosten. Evidensen for effekten af et meget lavt saltindtag, under fem gram dagligt, er dog meget begrænset....

  20. Manglende effekt af substitutionsbehandling ved alfa 1-antitrypsin-mangel

    DEFF Research Database (Denmark)

    Dahl, Ronald; Hilberg, Ole; Ottesen, Anders Løkke

    2011-01-01

    in the decrease of lung density measured by computed tomographies, but found no clinical nor statistical significant difference in respiratory symptoms, quality of life, lung function, use of medication, exacerbations, respiratory infections or survival. Based on the present evidence A1AT substitution therapy...

  1. Effekt af kompenserende strategier rettet mod kognitive deficits ved skizofreni

    DEFF Research Database (Denmark)

    Hansen, Jens Peter; Hounsgaard, Lise; Jensen, Birte Østergaard

    konkluderes, hvorvidt CAT kan tilbydes som supplement til nuværende tilbud. Formålet med undersøgelsen: At evaluere effekten af CAT behandling sammenlignet konventionel behandling med fokus på sociale funktioner, symptomer, tilbagefald, genindlæggelser og livskvalitet, hos ambulante patienter med skizofreni...

  2. Autenticitetsstrategier i Triers triologier - om at skabe affekt via effekt

    Directory of Open Access Journals (Sweden)

    Heidi Philipsen

    2007-04-01

    Full Text Available I denne artikel anskueliggøres, hvorledes forskellige filmiske strategier kan medvirke til at formidle autenticitetsfølelser til tilskueren. Artiklen diskuterer desuden ud fra eksempler, hvorledes filmisk autenticitet kan indkredses ved hjælp af Jay David Bolter og Richard Grusins begreber ’immediacy og ’hypermediacy’. Der argumenteres for, at der eksempelvis i film af Lars von Trier eksisterer et langt mere komplekst forhold mellem disse to begreber, end det anskues i Bolter og Grusins bog, Remediation. Men at begreberne fra denne bog kan medvirke til at kvalificere diskussionen om og forskning i autenticitet, bl.a. i nye film. Autenticitet, eller immediacy, optræder i Triers værker side om side og synes nærmest at betinge hinanden. Især filmen Idioterne (1999 analyseres i nærværende artikel som en film, der rummer en kompleks og særdeles iscenesat form for autenticitet. I denne film er bl.a. den radikale brug af filmiske virkemidler med til at skabe autenticitet. Artiklen medtænker endvidere, at ’de såkaldte naturlige historier’ ligeledes er strategier, der fremmaner følelsen af virkelighed både i Idioterne og andre nyere danske film.

  3. Hvor effektive og demokratiske er styringsnetværk?

    DEFF Research Database (Denmark)

    Sørensen, Eva; Torfing, Jacob

    2011-01-01

    Den stadigt mere velkonsoliderede governanceforskning har påvist, at styringsnetværk spiller en væsentlig rolle i offentlige styringsprocesser, og at netværk mellem offentlige og private aktører i stigende grad betragtes som et effektivt og legitimt styringsredskab. Der råder til gengæld betydeli...

  4. Positive effekter af diversitet på arbejdsmarkedet

    DEFF Research Database (Denmark)

    Foged, Mette

    2014-01-01

    This article provides a selective review of economic theory and empirical research on the labor market effects of immigration. The conclusion is that there are gains and redistributional consequences of immigration.......This article provides a selective review of economic theory and empirical research on the labor market effects of immigration. The conclusion is that there are gains and redistributional consequences of immigration....

  5. Har samfundstjeneste en præventiv effekt?

    DEFF Research Database (Denmark)

    Clausen, Susanne

    2007-01-01

    in judicial policy in the late 1990s after which the courts more frequently sentenced violent offenders to CS. The evaluation shows that after controlling for criminal history and socio-economic circumstances, some offenders sentenced to CS have lower rates of recidivism than offenders sentenced to prison...

  6. Sammenligning af sertindols og olanzapins effekt på kognition

    DEFF Research Database (Denmark)

    Nielsen, René Ernst

    Der er gennem de senere år kommet tiltagende fokus, både nationalt og internationalt, på de kognitive deficits der ses hos patienter med skizofreni. Det er kendt at den farmakologiske behandling har indflydelse på kognition funktion, men det er endnu ikke fyldestgørende klarlagt hvorledes de enke...... enkelte atypiske antipsykotika påvirker kognitiv funktion. Der vil blive beskrevet studiedesign for SEROLA studiet, som sammenligner sertindol og olanzapin med kognition, målt med CANTAB, som primært outcome....

  7. Nanocomposites for bone tissue regeneration.

    Science.gov (United States)

    Sahoo, Nanda Gopal; Pan, Yong Zheng; Li, Lin; He, Chao Bin

    2013-04-01

    Natural bone tissue possesses a nanocomposite structure that provides appropriate physical and biological properties. For bone tissue regeneration, it is crucial for the biomaterial to mimic living bone tissue. Since no single type of material is able to mimic the composition, structure and properties of native bone, nanocomposites are the best choice for bone tissue regeneration as they can provide the appropriate matrix environment, integrate desirable biological properties, and provide controlled, sequential delivery of multiple growth factors for the different stages of bone tissue regeneration. This article reviews the composition, structure and properties of advanced nanocomposites for bone tissue regeneration. It covers aspects of interest such as the biomimetic synthesis of bone-like nanocomposites, guided bone regeneration from inert biomaterials and bioactive nanocomposites, and nanocomposite scaffolds for bone tissue regeneration. The design, fabrication, and in vitro and in vivo characterization of such nanocomposites are reviewed.

  8. Mixed connective tissue disease.

    Science.gov (United States)

    Gunnarsson, Ragnar; Hetlevik, Siri Opsahl; Lilleby, Vibke; Molberg, Øyvind

    2016-02-01

    The concept of mixed connective tissue disease (MCTD) as a separate connective tissue disease (CTD) has persisted for more than four decades. High titers of antibodies targeting the U1 small nuclear ribonucleoprotein particle (U1 snRNP) in peripheral blood are a sine qua non for the diagnosis of MCTD, in addition to distinct clinical features including Raynaud's phenomenon (RP), "puffy hands," arthritis, myositis, pleuritis, pericarditis, interstitial lung disease (ILD), and pulmonary hypertension (PH). Recently, population-based epidemiology data from Norway estimated the point prevalence of adult-onset MCTD to be 3.8 per 100,000 and the mean annual incidence to be 2.1 per million per year, supporting the notion that MCTD is the least common CTD. Little is known about the etiology of MCTD, but recent genetic studies have confirmed that MCTD is a strongly HLA (​human leukocyte antigen)-linked disease, as the HLA profiles of MCTD differ distinctly from the corresponding profiles of ethnically matched healthy controls and other CTDs. In the first section of this review, we provide an update on the clinical, immunological, and genetic features of MCTD and discuss the relationship between MCTD and the other CTDs. Then we proceed to discuss the recent advances in therapy and our current understanding of prognosis and prognostic factors, especially those that are associated with the more serious pulmonary and cardiovascular complications of the disease. In the final section, we discuss some of the key, unresolved questions related to anti-RNP-associated diseases and indicate how these questions may be approached in future studies. Copyright © 2016. Published by Elsevier Ltd.

  9. Systemische Effekte von inhalierten ultrafeinen Kohlenstoffpartikeln in Hinblick auf entzündliche Effekte und kardiovaskuläre Erkrankungen

    OpenAIRE

    Ettehadieh, Dariusch

    2010-01-01

    Die Exposition mit Umweltstäuben, ultrafeinen Partikeln und Gasen wird als Ursache akuter kardiovaskulärer Morbidität und Mortalität angesehen. Epidemiologische und toxikologische Studien der letzten Jahre weisen auf die Bedeutung von ultrafeinen Partikeln als Auslöser für die lokalen pulmonalen und systemischen Entzündungsreaktionen hin, die durch Veränderungen in der kardiovaskulären Funktion gekennzeichnet sind. Dazu gehören endotheliale Dysfunktion und prothrombotische Prozesse, ...

  10. Integrating soft and hard tissues via interface tissue engineering.

    Science.gov (United States)

    Patel, Sahishnu; Caldwell, Jon-Michael; Doty, Stephen B; Levine, William N; Rodeo, Scott; Soslowsky, Louis J; Thomopoulos, Stavros; Lu, Helen H

    2017-11-17

    The enthesis, or interface between bone and soft tissues such as ligament and tendon, is prone to injury and often does not heal, even post surgical intervention. Interface tissue engineering represents an integrative strategy for regenerating the native enthesis by functionally connecting soft and hard tissues and thereby improving clinical outcome. This review focuses on integrative and cell-instructive scaffold designs that target the healing of the two most commonly injured soft tissue-bone junctions: tendon-bone interface (e.g., rotator cuff) and ligament-bone interface (e.g., anterior cruciate ligament). The inherent connectivity between soft and hard tissues is instrumental for musculoskeletal motion and is therefore a key design criterion for soft tissue regeneration. To this end, scaffold design for soft tissue regeneration have progressed from single tissue systems to the emerging focus on pre-integrated and functional composite tissue units. Specifically, a multifaceted, bioinspired approach has been pursued wherein scaffolds are tailored to stimulate relevant cell responses using spatially patterned structural and chemical cues, growth factors, and/or mechanical stimulation. Moreover, current efforts to elucidate the essential scaffold design criteria via strategic biomimicry are emphasized as these will reduce complexity in composite tissue regeneration and ease the related burden for clinical translation. These innovative studies underscore the clinical relevance of engineering connective tissue integration and have broader impact in the formation of complex tissues and total joint regeneration. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  11. Tritium metabolism in rat tissues

    International Nuclear Information System (INIS)

    Takeda, H.

    1982-01-01

    As part of a series of studies designed to evaluate the relative radiotoxicity of various tritiated compounds, metabolism of tritium in rat tissues was studied after administration of tritiated water, leucine, thymidine, and glucose. The distribution and retention of tritium varied widely, depending on the chemical compound administered. Tritium introduced as tritiated water behaved essentially as body water and became uniformly distributed among the tissues. However, tritium administered as organic compounds resulted in relatively high incorporation into tissue constituents other than water, and its distribution differed among the various tissues. Moreover, the excretion rate of tritium from tissues was slower for tritiated organic compounds than for tritiated water. Administrationof tritiated organic compounds results in higher radiation doses to the tissues than does administration of tritiated water. Among the tritiated compounds examined, for equal radioactivity administered, leucine gave the highest radiation dose, followed in turn by thymidine, glucose, and water. (author)

  12. Bioprinting for Neural Tissue Engineering.

    Science.gov (United States)

    Knowlton, Stephanie; Anand, Shivesh; Shah, Twisha; Tasoglu, Savas

    2018-01-01

    Bioprinting is a method by which a cell-encapsulating bioink is patterned to create complex tissue architectures. Given the potential impact of this technology on neural research, we review the current state-of-the-art approaches for bioprinting neural tissues. While 2D neural cultures are ubiquitous for studying neural cells, 3D cultures can more accurately replicate the microenvironment of neural tissues. By bioprinting neuronal constructs, one can precisely control the microenvironment by specifically formulating the bioink for neural tissues, and by spatially patterning cell types and scaffold properties in three dimensions. We review a range of bioprinted neural tissue models and discuss how they can be used to observe how neurons behave, understand disease processes, develop new therapies and, ultimately, design replacement tissues. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Computational Modeling in Tissue Engineering

    CERN Document Server

    2013-01-01

    One of the major challenges in tissue engineering is the translation of biological knowledge on complex cell and tissue behavior into a predictive and robust engineering process. Mastering this complexity is an essential step towards clinical applications of tissue engineering. This volume discusses computational modeling tools that allow studying the biological complexity in a more quantitative way. More specifically, computational tools can help in:  (i) quantifying and optimizing the tissue engineering product, e.g. by adapting scaffold design to optimize micro-environmental signals or by adapting selection criteria to improve homogeneity of the selected cell population; (ii) quantifying and optimizing the tissue engineering process, e.g. by adapting bioreactor design to improve quality and quantity of the final product; and (iii) assessing the influence of the in vivo environment on the behavior of the tissue engineering product, e.g. by investigating vascular ingrowth. The book presents examples of each...

  14. Soft tissue angiosarcomas

    Energy Technology Data Exchange (ETDEWEB)

    Morales, P.H.; Lindberg, R.D.; Barkley, H.T.

    1981-12-01

    From 1949 to 1979, 12 patients with soft tissue angiosarcoma received radiotherapy (alone or in combination with other modalities of treatment) with curative intent at The University of Texas M.D. Anderson Hospital and Tumor Institute. The primary site was the head and neck in six patients (scalp, four; maxillary antrum, one; and oral tongue, one), the breast in four patients, and the thigh in two patients. All four patients with angiosarcoma of the scalp had advanced multifocal tumors, and two of them had clinically positive neck nodes. None of these tumors were controlled locally, and local recurrences occurred within and/or at a distance from the generous fields of irradiation. The remaining two patients with head and neck lesions had their disease controlled by surgery and postoperative irradiation. Three of the four angiosarcomas of the breast were primary cases which were treated by a combination of surgery (excisional biopsy, simple mastectomy, radical mastectomy) and postoperative irradiation. One patient also received adjuvant chemotherapy. The fourth patient was treated for scar recurrence after radical mastectomy. All four patients had their disease locally controlled, and two of them have survived over 5 years. The two patients with angiosarcoma of the thigh were treated by conservative surgical excision and postoperative irradiation. One patient had her disease controlled; the other had a local recurrence requiring hip disarticulation and subsequent hemipelvectomy for salvage.

  15. Synthetic Phage for Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    So Young Yoo

    2014-01-01

    Full Text Available Controlling structural organization and signaling motif display is of great importance to design the functional tissue regenerating materials. Synthetic phage, genetically engineered M13 bacteriophage has been recently introduced as novel tissue regeneration materials to display a high density of cell-signaling peptides on their major coat proteins for tissue regeneration purposes. Structural advantages of their long-rod shape and monodispersity can be taken together to construct nanofibrous scaffolds which support cell proliferation and differentiation as well as direct orientation of their growth in two or three dimensions. This review demonstrated how functional synthetic phage is designed and subsequently utilized for tissue regeneration that offers potential cell therapy.

  16. Clinical management of soft tissue sarcomas

    International Nuclear Information System (INIS)

    Pinedo, H.M.; Verweij, J.

    1986-01-01

    This book is concerned with the clinical management of soft tissue sarcomas. Topics covered include: Radiotherapy; Pathology of soft tissue sarcomas; Surgical treatment of soft tissue sarcomas; and Chemotherapy in advanced soft tissue sarcomas

  17. Undiagnosed connective tissue diseases

    Science.gov (United States)

    Cavagna, Lorenzo; Codullo, Veronica; Ghio, Stefano; Scirè, Carlo Alberto; Guzzafame, Eleonora; Scelsi, Laura; Rossi, Silvia; Montecucco, Carlomaurizio; Caporali, Roberto

    2016-01-01

    Abstract Among different subgroups of pulmonary arterial hypertension (PAH), those associated with connective tissue diseases (CTDs) have distinct hemodynamic and prognostic features; a correct etiologic diagnosis is thus mandatory. To estimate frequency and prognosis of previously undiagnosed CTDs in a suspect idiopathic (i) PAH cohort. Consecutive patients with PAH confirmed by right heart catheterization referred at the Cardiology Division of our Hospital without a previous rheumatological assessment or the occurrence of other conditions explaining PAH were checked for CTD by a clinical, laboratory, and instrumental evaluation. Survival in each group has also been analyzed. In our study 17 of 49 patients were classified as CTD-PAH, corresponding to a prevalence (95% CI) of 34.7% (21.7–49.6%). ANA positivity had 94% (71.3–99.9%) sensitivity and 78.1% (60–90.7%) specificity for a diagnosis of CTD-PAH; Raynaud phenomenon (RP) showed 83.3% (51.6–97.9%) sensitivity and 100% (90.5–100%) specificity for the diagnosis of Systemic Sclerosis (SSc)-PAH. At diagnosis, SSc patients were older and had a lower creatinine clearance compared with iPAH and other CTD-PAH. After a median follow-up of 44 (2–132) months, 18 of 49 (36.7%) patients died: 31.2% in the iPAH group, 20% in the CTD-, and 58.3% in the SSc-PAH group. Mortality was significantly higher in SSc-PAH (HR 3.32, 1.11–9.95, P <0.05) versus iPAH. We show a high prevalence of undiagnosed CTDs in patients with iPAH without a previous rheumatological assessment. All patients with RP were diagnosed with SSc. Our data stress the importance of a rheumatological assessment in PAH, especially because of the unfavorable prognostic impact of an associated SSc. PMID:27684814

  18. Obesity Decreases Perioperative Tissue Oxygenation

    Science.gov (United States)

    Kabon, Barbara; Nagele, Angelika; Reddy, Dayakar; Eagon, Chris; Fleshman, James W.; Sessler, Daniel I.; Kurz, Andrea

    2005-01-01

    Background: Obesity is an important risk factor for surgical site infections. The incidence of surgical wound infections is directly related to tissue perfusion and oxygenation. Fat tissue mass expands without a concomitant increase in blood flow per cell, which might result in a relative hypoperfusion with decreased tissue oxygenation. Consequently, we tested the hypotheses that perioperative tissue oxygen tension is reduced in obese surgical patients. Furthermore, we compared the effect of supplemental oxygen administration on tissue oxygenation in obese and non-obese patients. Methods: Forty-six patients undergoing major abdominal surgery were assigned to one of two groups according to their body mass index (BMI): BMI < 30 kg/m2 (non-obese) and BMI ≥ 30 kg/m2 (obese). Intraoperative oxygen administration was adjusted to arterial oxygen tensions of ≈150 mmHg and ≈300 mmHg in random order. Anesthesia technique and perioperative fluid management were standardized. Subcutaneous tissue oxygen tension was measured with a polarographic electrode positioned within a subcutaneous tonometer in the lateral upper arm during surgery, in the recovery room, and on the first postoperative day. Postoperative tissue oxygen was also measured adjacent to the wound. Data were compared with unpaired two tailed t-tests and Wilcoxon rank-sum tests; P < 0.05 was considered statistically significant. Results: Intraoperative subcutaneous tissue oxygen tension was significantly less in the obese patients at baseline (36 vs. 57 mmHg, P = 0.002) and with supplemental oxygen administration (47 vs. 76 mmHg, P = 0.014). Immediate postoperative tissue oxygen tension was also significantly less in subcutaneous tissue of the upper arm (43 vs. 54 mmHg, P = 0.011) as well as near the incision (42 vs. 62 mmHg, P = 0.012) in obese patients. In contrast, tissue oxygen tension was comparable in each group on the first postoperative morning. Conclusion: Wound and tissue hypoxia were common in obese

  19. [Cellular subcutaneous tissue. Anatomic observations].

    Science.gov (United States)

    Marquart-Elbaz, C; Varnaison, E; Sick, H; Grosshans, E; Cribier, B

    2001-11-01

    We showed in a companion paper that the definition of the French "subcutaneous cellular tissue" considerably varied from the 18th to the end of the 20th centuries and has not yet reached a consensus. To address the anatomic reality of this "subcutaneous cellular tissue", we investigated the anatomic structures underlying the fat tissue in normal human skin. Sixty specimens were excised from the surface to the deep structures (bone, muscle, cartilage) on different body sites of 3 cadavers from the Institut d'Anatomie Normale de Strasbourg. Samples were paraffin-embedded, stained and analysed with a binocular microscope taking x 1 photographs. Specimens were also excised and fixed after subcutaneous injection of Indian ink, after mechanic tissue splitting and after performing artificial skin folds. The aspects of the deep parts of the skin greatly varied according to their anatomic localisation. Below the adipose tissue, we often found a lamellar fibrous layer which extended from the interlobular septa and contained horizontally distributed fat cells. No specific tissue below the hypodermis was observed. Artificial skin folds concerned either exclusively the dermis, when they were superficial or included the hypodermis, but no specific structure was apparent in the center of the fold. India ink diffused to the adipose tissue, mainly along the septa, but did not localise in a specific subcutaneous compartment. This study shows that the histologic aspects of the deep part of the skin depend mainly on the anatomic localisation. Skin is composed of epidermis, dermis and hypodermis and thus the hypodermis can not be considered as being "subcutaneous". A difficult to individualise, fibrous lamellar structure in continuity with the interlobular septa is often found under the fat lobules. This structure is a cleavage line, as is always the case with loose connective tissues, but belongs to the hypodermis (i.e. fat tissue). No specific tissue nor any virtual space was

  20. Cryobanking of human ovarian tissue

    DEFF Research Database (Denmark)

    Ernst, Erik; Andersen, Anders Nyboe; Andersen, Claus Yding

    2014-01-01

    Cryopreservation of ovarian tissue is one way of preserving fertility in young women with a malignant disease or other disorders that require gonadotoxic treatment. The purpose of the study was to explore how many women remained interested in continued cryostorage of their ovarian tissue beyond a...

  1. Biomimetic heterogenous elastic tissue development.

    Science.gov (United States)

    Tsai, Kai Jen; Dixon, Simon; Hale, Luke Richard; Darbyshire, Arnold; Martin, Daniel; de Mel, Achala

    2017-01-01

    There is an unmet need for artificial tissue to address current limitations with donor organs and problems with donor site morbidity. Despite the success with sophisticated tissue engineering endeavours, which employ cells as building blocks, they are limited to dedicated labs suitable for cell culture, with associated high costs and long tissue maturation times before available for clinical use. Direct 3D printing presents rapid, bespoke, acellular solutions for skull and bone repair or replacement, and can potentially address the need for elastic tissue, which is a major constituent of smooth muscle, cartilage, ligaments and connective tissue that support organs. Thermoplastic polyurethanes are one of the most versatile elastomeric polymers. Their segmented block copolymeric nature, comprising of hard and soft segments allows for an almost limitless potential to control physical properties and mechanical behaviour. Here we show direct 3D printing of biocompatible thermoplastic polyurethanes with Fused Deposition Modelling, with a view to presenting cell independent in-situ tissue substitutes. This method can expeditiously and economically produce heterogenous, biomimetic elastic tissue substitutes with controlled porosity to potentially facilitate vascularisation. The flexibility of this application is shown here with tubular constructs as exemplars. We demonstrate how these 3D printed constructs can be post-processed to incorporate bioactive molecules. This efficacious strategy, when combined with the privileges of digital healthcare, can be used to produce bespoke elastic tissue substitutes in-situ, independent of extensive cell culture and may be developed as a point-of-care therapy approach.

  2. Mechanical device for tissue regeneration

    NARCIS (Netherlands)

    Herder, J.L.; Maij, E.

    2010-01-01

    The invention relates to a mechanical device for tissue- regeneration inside a patient, comprising means (2, 3) to place a scaffold for the tissue under mechanical stress. Said means comprise a first device-part (2) and a second device-part (3) which parts are arranged to be movable with respect to

  3. Biomaterials for tissue engineering: summary

    Science.gov (United States)

    Christenson, L.; Mikos, A. G.; Gibbons, D. F.; Picciolo, G. L.; McIntire, L. V. (Principal Investigator)

    1997-01-01

    This article summarizes presentations and discussion at the workshop "Enabling Biomaterial Technology for Tissue Engineering," which was held during the Fifth World Biomaterials Congress in May 1996. Presentations covered the areas of material substrate architecture, barrier effects, and cellular response, including analysis of biomaterials challenges involved in producing specific tissue-engineered products.

  4. Tissue engineering of the meniscus.

    NARCIS (Netherlands)

    Buma, P.; Ramrattan, N.N.; Tienen, T. van; Veth, R.P.H.

    2004-01-01

    Meniscus lesions are among the most frequent injuries in orthopaedic practice and they will inevitably lead to degeneration of the knee articular cartilage. The fibro-cartilage-like tissue of the meniscus is notorious for its limited regenerative capacity. Tissue engineering could offer new

  5. Transcatheter tissue engineered heart valves.

    Science.gov (United States)

    Emmert, Maximilian Y; Weber, Benedikt; Falk, Volkmar; Hoerstrup, Simon P

    2014-01-01

    Valvular heart disease represents a leading cause of mortality worldwide. Transcatheter heart valve replacement techniques have been recently introduced into the clinical routine expanding the treatment options for affected patients. However, despite this technical progress toward minimally invasive, transcatheter strategies, the available heart valve prostheses for these techniques are bioprosthetic and associated with progressive degeneration. To overcome such limitations, the concept of heart valve tissue engineering has been repeatedly suggested for future therapy concepts. Ideally, a clinically relevant heart valve tissue engineering concept would combine minimally invasive strategies for both, living autologous valve generation as well as valve implantation. Therefore, merging transcatheter techniques with living tissue engineered heart valves into a trascatheter tissue engineered heart valve concept could significantly improve current treatment options for patients suffering from valvular heart disease. This report provides an overview on transcatheter tissue engineered heart valves and summarizes available pre-clinical data.

  6. Commercial considerations in tissue engineering.

    Science.gov (United States)

    Mansbridge, Jonathan

    2006-10-01

    Tissue engineering is a field with immense promise. Using the example of an early tissue-engineered skin implant, Dermagraft, factors involved in the successful commercial development of devices of this type are explored. Tissue engineering has to strike a balance between tissue culture, which is a resource-intensive activity, and business considerations that are concerned with minimizing cost and maximizing customer convenience. Bioreactor design takes place in a highly regulated environment, so factors to be incorporated into the concept include not only tissue culture considerations but also matters related to asepsis, scaleup, automation and ease of use by the final customer. Dermagraft is an allogeneic tissue. Stasis preservation, in this case cryopreservation, is essential in allogeneic tissue engineering, allowing sterility testing, inventory control and, in the case of Dermagraft, a cellular stress that may be important for hormesis following implantation. Although the use of allogeneic cells provides advantages in manufacturing under suitable conditions, it raises the spectre of immunological rejection. Such rejection has not been experienced with Dermagraft. Possible reasons for this and the vision of further application of allogeneic tissues are important considerations in future tissue-engineered cellular devices. This review illustrates approaches that indicate some of the criteria that may provide a basis for further developments. Marketing is a further requirement for success, which entails understanding of the mechanism of action of the procedure, and is illustrated for Dermagraft. The success of a tissue-engineered product is dependent on many interacting operations, some discussed here, each of which must be performed simultaneously and well.

  7. Can the 'Assessment Drives Learning' effect be detected in clinical skills training? - Implications for curriculum design and resource planning [Der “Assessment Drives Learning”-Effekt beim Training klinisch-praktischer Fertigkeiten - Implikationen für die Curriculumsgestaltung und die Planung von Ressourcen

    Directory of Open Access Journals (Sweden)

    Buss, Beate

    2012-11-01

    utilisation of voluntary skills-lab training in order to reach a sufficient concordance between students’ requirements and faculty offers, as well as resource management.[german] Zielsetzung: Die Vermittlung klinisch-praktischer Fertigkeiten ist von entscheidender Bedeutung für die Berufsfähigkeit angehender Ärzte. Prozedurale Fertigkeiten werden dabei häufig zu allererst in sogenannten Skills-Labs trainiert, die eine geschützte Lernumgebung gewährleisten. Die Implementierung und auch Pflege von Skills-Labs stellt allerdings eine nicht geringfügige finanzielle Herausforderung dar. Aus diesem Grund hat sich die vorliegende Arbeit zum Ziel gesetzt, die Besuchsfrequenzen und –muster im Rahmen freiwilliger Skills-Lab-Unterrichtseinheiten zu untersuchen, um folgende Frage zu beantworten: Kann der in der Literatur beschriebene, motivationspsychologische Effekt des “Assessment drives learning” festgestellt werden und spiegelt sich dieser in dem Besuchsverhalten von Studierenden in freiwilligen Skills-Lab-Unterrichtseinheiten wider? Ausgehend von den Studienergebnissen sollen Empfehlungen für die Curriculumsplanung und das Ressourcenmanagement abgeleitet werden.Methode:. Eine retrospektive, deskriptive Analyse studentischen Inanspruchnahmeverhaltens sowohl von freiwilligen „Basic“- als auch „Advanced“ Skills-Lab-Unterrichtseinheiten wurde durchgeführt. Hierzu wurden Teilnahmemuster von 340 Medizinstudierenden des dritten Studienjahres verschiedener Jahrgänge an der Medizinischen Fakultät Heidelberg näher untersucht.Ergebnisse: Die Studierenden zeigten besonders zu Beginn und am Ende des Semesters eine Präferenz für die Teilnahme an freiwilligen “Basic“ Skills-Lab-Unterrichtseinheiten, die für die klinisch-praktische Prüfung relevant sind. Freiwillige “Advanced“ Skills-Lab”-Unterrichtseinheiten ohne Bezug zur klinisch-praktischen Prüfung wurden vor allem zu Beginn des Semesters genutzt, mit einem Rückgang der Besuche gegen Ende des Semesters

  8. Force transmission in epithelial tissues.

    Science.gov (United States)

    Vasquez, Claudia G; Martin, Adam C

    2016-03-01

    In epithelial tissues, cells constantly generate and transmit forces between each other. Forces generated by the actomyosin cytoskeleton regulate tissue shape and structure and also provide signals that influence cells' decisions to divide, die, or differentiate. Forces are transmitted across epithelia because cells are mechanically linked through junctional complexes, and forces can propagate through the cell cytoplasm. Here, we review some of the molecular mechanisms responsible for force generation, with a specific focus on the actomyosin cortex and adherens junctions. We then discuss evidence for how these mechanisms promote cell shape changes and force transmission in tissues. © 2016 Wiley Periodicals, Inc.

  9. Soft tissue tumors - imaging methods

    International Nuclear Information System (INIS)

    Arlart, I.P.

    1985-01-01

    Soft Tissue Tumors - Imaging Methods: Imaging methods play an important diagnostic role in soft tissue tumors concerning a preoperative evaluation of localization, size, topographic relationship, dignity, and metastatic disease. The present paper gives an overview about diagnostic methods available today such as ultrasound, thermography, roentgenographic plain films and xeroradiography, radionuclide methods, computed tomography, lymphography, angiography, and magnetic resonance imaging. Besides sonography particularly computed tomography has the most important diagnostic value in soft tissue tumors. The application of a recently developed method, the magnetic resonance imaging, cannot yet be assessed in its significance. (orig.) [de

  10. Tissue Engineering in Vesical Reconstruction

    African Journals Online (AJOL)

    mn

    Azhar University, Assiut, Egypt. ABSTRACT. Objectives: This review summarizes the basic principles of tissue engineering (TE) and describes the possible future clinical application in bladder reconstruction. Material and Methods: This review ...

  11. Tissue Harmonic Synthetic Aperture Imaging

    DEFF Research Database (Denmark)

    Rasmussen, Joachim

    The main purpose of this PhD project is to develop an ultrasonic method for tissue harmonic synthetic aperture imaging. The motivation is to advance the field of synthetic aperture imaging in ultrasound, which has shown great potentials in the clinic. Suggestions for synthetic aperture tissue...... system complexity compared to conventional synthetic aperture techniques. In this project, SASB is sought combined with a pulse inversion technique for 2nd harmonic tissue harmonic imaging. The advantages in tissue harmonic imaging (THI) are expected to further improve the image quality of SASB....... The first part of the scientific contribution investigates an implementation of pulse inversion for THI on the experimental ultrasound system SARUS. The technique is initially implemented for linear array transducers and then expanded for convex array transducers. The technique is evaluated based on spatial...

  12. Heritable Disorders of Connective Tissue

    Science.gov (United States)

    ... skin. Epidermolysis bullosa affects the skin, causing blisters. Marfan syndrome can affect the heart, blood vessels, lungs, eyes, ... Disorders of Connective Tissue, Questions and Answers about Marfan Syndrome, Questions and Answers about Marfan Syndrome, Easy-to- ...

  13. Microdissection of stained archival tissue.

    Science.gov (United States)

    Gupta, S K; Douglas-Jones, A G; Morgan, J M

    1997-08-01

    In many tissues the preinvasive stage of neoplastic progression can be identified histologically as dysplasia or in situ disease. There is much interest in defining the molecular events associated with the early stages of neoplasia. Retrieval of histologically recognisable preinvasive neoplastic tissue uncontaminated by inflammatory or stromal cells is important for genetic studies using polymerase chain reaction (PCR) assay. A novel method for microdissection is described in which 10 microns sections are dewaxed, stained with haematoxylin and eosin, dried, covered with Sellotape, and the tissue cut out using a scalpel blade under direct visual control. The method is quick, eliminates problems of operator tremor, preserves the architecture of the micro-dissected tissue (for photographic documentation) and requires no special equipment. The presence of Sellotape and adhesive in the reaction mixture has no detrimental effect on the ability to extract DNA or to perform PCR.

  14. Molecular, cellular, and tissue engineering

    CERN Document Server

    Bronzino, Joseph D

    2015-01-01

    Known as the bible of biomedical engineering, The Biomedical Engineering Handbook, Fourth Edition, sets the standard against which all other references of this nature are measured. As such, it has served as a major resource for both skilled professionals and novices to biomedical engineering. Molecular, Cellular, and Tissue Engineering, the fourth volume of the handbook, presents material from respected scientists with diverse backgrounds in molecular biology, transport phenomena, physiological modeling, tissue engineering, stem cells, drug delivery systems, artificial organs, and personalized medicine. More than three dozen specific topics are examined, including DNA vaccines, biomimetic systems, cardiovascular dynamics, biomaterial scaffolds, cell mechanobiology, synthetic biomaterials, pluripotent stem cells, hematopoietic stem cells, mesenchymal stem cells, nanobiomaterials for tissue engineering, biomedical imaging of engineered tissues, gene therapy, noninvasive targeted protein and peptide drug deliver...

  15. Necrotizing soft-tissue infections.

    Science.gov (United States)

    Ahrenholz, D H

    1988-02-01

    A variety of infections are encountered by the practicing surgeon. Uncommonly, a patient presents with minimal external manifestations of a deep surgical soft-tissue infection. Early aggressive intervention is required to minimize the morbidity in these often debilitated patients.

  16. PEPTIDASE DISTRIBUTION IN LYMPHATIC TISSUE

    Science.gov (United States)

    Doyle, William L.

    1955-01-01

    The lymphatic tissue of the rabbit contains a labile peptidase as measured by the hydrolysis of alanylglycine. Some characteristics of the enzyme were determined. This enzyme increases in amount when the numbers of macrophages in the tissue are increased and it is also present in the extracellular fluid in high concentration. The extracellular fluid value for this activity is calculated to be about 8 times the value for serum. Based on a correlation between the types of cells present and the amount of peptidase found in the tissue the following relative activities are assigned to the tissue components per unit volume: lymphocytes 1.0, tissue fluid 11.0, serum 1.4, phagocytes (macrophages) 30.0, reticular cells 12.0. The amount of chloride space varied from 35 to 55 per cent. The relative amounts of acid phosphatase per unit volume in the same elements were calculated to be: lymphocytes 1.0, tissue fluid 0, phagocytes 20.0, and reticular cells 4.0. Analysis of the distribution of peptidase was facilitated by simultaneous determination of acid phosphatase whose primary localization in one cell type was known. The over-all contribution of lymphocytes to the labile peptidase content of lymphatic tissue is relatively minor and was not found to exceed 5 per cent of the average value for the entire nodular tissue. In the absence of large numbers of macrophages the intercellular fluid of the nodule accounts for half or more of the peptidase content of the nodules. PMID:13242588

  17. Magnetic resonance of calcified tissues

    Science.gov (United States)

    Wehrli, Felix W.

    2013-04-01

    MRI of the human body is largely made possible by the favorable relaxation properties of protons of water and triacyl glycerides prevalent in soft tissues. Hard tissues - key among them bone - are generally less amenable to measurement with in vivo MR imaging techniques, not so much as a result of the lower proton density but rather due to the extremely short life-times of the proton signal in water bound to solid-like entities, typically collagen, or being trapped in micro-pores. Either mechanism can enhance T2 relaxation by up to three orders of magnitude relative to their soft-tissue counterparts. Detection of these protons requires solid-state techniques that have emerged in recent years and that promise to add a new dimension to the study of hard tissues. Alternative approaches to probe calcified tissues exploit their characteristic magnetic properties. Bone, teeth and extra-osseous calcium-containing biomaterials are unique in that they are more diamagnetic than all other tissues and thus yield information indirectly by virtue of the induced magnetic fields present in their vicinity. Progress has also been made in methods allowing very high-resolution structural imaging of trabecular and cortical bone relying on detection of the surrounding soft-tissues. This brief review, much of it drawn from work conducted in the author's laboratory, seeks to highlight opportunities with focus on early-stage developments for image-based assessment of structure, function, physiology and mechanics of calcified tissues in humans via liquid and solid-state approaches, including proton, deuteron and phosphorus NMR and MRI.

  18. Microdissection of stained archival tissue.

    OpenAIRE

    Gupta, S K; Douglas-Jones, A G; Morgan, J M

    1997-01-01

    In many tissues the preinvasive stage of neoplastic progression can be identified histologically as dysplasia or in situ disease. There is much interest in defining the molecular events associated with the early stages of neoplasia. Retrieval of histologically recognisable preinvasive neoplastic tissue uncontaminated by inflammatory or stromal cells is important for genetic studies using polymerase chain reaction (PCR) assay. A novel method for microdissection is described in which 10 microns...

  19. [Soft tissue rheumatism in erderly].

    Science.gov (United States)

    Szczepański, Leszek

    2008-01-01

    Disorders of soft, peri-articular tissues are a common cause of musculoskeletal pain in elderly patients. Nevertheless, most physicians underestimate the role of soft tissue rheumatism in the pathomechanism of the pain. The impairments of soft tissue can not be diagnosed by X-rays examinations, whereas degenerative lesions of joints are easy diagnosed using this method even despite of their uncertain role in producing the symptoms. The incidence of pain syndromes originated from soft tissues differ regarding to the age of patients. In young subjects the incidence of all of them is generally low. Syndromes provoked by overloading during work: repetitive strain syndrome, canal tunnel syndrome, tennis elbow, golfers elbow, shoulder tendon coin disorders and myofascial pain syndrome are common in middle-aged patients. The morbidity of fibromialgia syndrome is also lower in old people probably as the result of diminished numbers and degenerative changes in nociceptive fibers. The syndromes prevailing in elderly patients include trochanteric syndrome and the pain syndromes provoked by muscle spasm depended on posture abnormalities. In the soft tissue pain syndrome prevention adapted to old age kinesitherapy and avoiding muscle overloading are recommended. Soft tissue pain syndromes are usually treated with non steroidal anti inflammatory drugs. In local pain syndromes better results can be obtained by local treatment. Local injections of glikocorticosteroids are usually very effective and safe.

  20. Tissue Banking: Current procedures, ethical consideration and ...

    African Journals Online (AJOL)

    Tissue banking provides safe and effective cells and tissues for transplantation in reconstruction surgery. Bone, amnion, skin, cartilage, heart valves and xenograft tissues are the most commonly used biological tissues. Acquisition of tissue is dependent on elaborate donor screening criteria based on medical and social ...

  1. Nanostructured Biomaterials for Tissue Engineered Bone Tissue Reconstruction

    Directory of Open Access Journals (Sweden)

    Bressan Eriberto

    2012-01-01

    Full Text Available Bone tissue engineering strategies are emerging as attractive alternatives to autografts and allografts in bone tissue reconstruction, in particular thanks to their association with nanotechnologies. Nanostructured biomaterials, indeed, mimic the extracellular matrix (ECM of the natural bone, creating an artificial microenvironment that promotes cell adhesion, proliferation and differentiation. At the same time, the possibility to easily isolate mesenchymal stem cells (MSCs from different adult tissues together with their multi-lineage differentiation potential makes them an interesting tool in the field of bone tissue engineering. This review gives an overview of the most promising nanostructured biomaterials, used alone or in combination with MSCs, which could in future be employed as bone substitutes. Recent works indicate that composite scaffolds made of ceramics/metals or ceramics/polymers are undoubtedly more effective than the single counterparts in terms of osteoconductivity, osteogenicity and osteoinductivity. A better understanding of the interactions between MSCs and nanostructured biomaterials will surely contribute to the progress of bone tissue engineering.

  2. Melanin content of hamster tissues, human tissues, and various melanomas

    Energy Technology Data Exchange (ETDEWEB)

    Watts, K.P.; Fairchild, R.G.; Slatkin, D.N.; Greenberg, D.; Packer, S.; Atkins, H.L.; Hannon, S.J.

    1981-02-01

    Melanin content (percentage by weight) was determined in both pigmented and nonpigmented tissues of Syrian golden hamsters bearing Greene melanoma. Melanin content was also measured in various other melanoma models (B-16 in C57 mice, Harding-Passey in BALB/c mice, and KHDD in C3H mice) and in nine human melanomas, as well as in selected normal tissues. The purpose was to evaluate the possible efficacy of chlorpromazine, which is known to bind to melanin, as a vehicle for boron transport in neutron capture therapy. Successful therapy would depend upon selective uptake and absolute concentration of borated compounds in tumors; these parameters will in turn depend upon melanin concentration in melanomas and nonpigmented ''background'' tissues. Hamster whole eyes, hamster melanomas, and other well-pigmented animal melanomas were found to contain 0.3 to 0.8% melanin by weight, whereas human melanomas varied from 0.1 to 0.9% (average, 0.35%). Other tissues, with the exception of skin, were lower in content by a factor of greater than or equal to30. Melanin pigment was extracted from tissues, and the melanin content was determined spectrophotometrically. Measurements were found to be sensitive to the presence of other proteins. Previous procedures for isolating and quantifying melanin often neglected the importance of removing proteins and other interfering nonmelanic substances.

  3. Soft tissue engineering with micronized-gingival connective tissues.

    Science.gov (United States)

    Noda, Sawako; Sumita, Yoshinori; Ohba, Seigo; Yamamoto, Hideyuki; Asahina, Izumi

    2018-01-01

    The free gingival graft (FGG) and connective tissue graft (CTG) are currently considered to be the gold standards for keratinized gingival tissue reconstruction and augmentation. However, these procedures have some disadvantages in harvesting large grafts, such as donor-site morbidity as well as insufficient gingival width and thickness at the recipient site post-treatment. To solve these problems, we focused on an alternative strategy using micronized tissue transplantation (micro-graft). In this study, we first investigated whether transplantation of micronized gingival connective tissues (MGCTs) promotes skin wound healing. MGCTs (≤100 µm) were obtained by mincing a small piece (8 mm 3 ) of porcine keratinized gingiva using the RIGENERA system. The MGCTs were then transplanted to a full skin defect (5 mm in diameter) on the dorsal surface of immunodeficient mice after seeding to an atelocollagen matrix. Transplantations of atelocollagen matrixes with and without micronized dermis were employed as experimental controls. The results indicated that MGCTs markedly promote the vascularization and epithelialization of the defect area 14 days after transplantation compared to the experimental controls. After 21 days, complete wound closure with low contraction was obtained only in the MGCT grafts. Tracking analysis of transplanted MGCTs revealed that some mesenchymal cells derived from MGCTs can survive during healing and may function to assist in wound healing. We propose here that micro-grafting with MGCTs represents an alternative strategy for keratinized tissue reconstruction that is characterized by low morbidity and ready availability. © 2017 Wiley Periodicals, Inc.

  4. Tissue-electronics interfaces: from implantable devices to engineered tissues

    Science.gov (United States)

    Feiner, Ron; Dvir, Tal

    2018-01-01

    Biomedical electronic devices are interfaced with the human body to extract precise medical data and to interfere with tissue function by providing electrical stimuli. In this Review, we outline physiologically and pathologically relevant tissue properties and processes that are important for designing implantable electronic devices. We summarize design principles for flexible and stretchable electronics that adapt to the mechanics of soft tissues, such as those including conducting polymers, liquid metal alloys, metallic buckling and meandering architectures. We further discuss technologies for inserting devices into the body in a minimally invasive manner and for eliminating them without further intervention. Finally, we introduce the concept of integrating electronic devices with biomaterials and cells, and we envision how such technologies may lead to the development of bionic organs for regenerative medicine.

  5. Photochemical Tissue Bonding: Photons for Healing

    National Research Council Canada - National Science Library

    Redmond, Robert W; Kochevar, Irene E; Amann, Christopher; Chan, Barbara P; Farinelli, William A; Anderson, R. R; Azar, Dimitri T; Johnson, T. S; Winograd, J; Randolph, Mark A

    2004-01-01

    ...) formed between protein molecules bind the tissue surfaces together. In our PTB approach the photosensitizer used superficially stains the tissue such that effects are limited to the tissue interface...

  6. Radiosensitivity of soft tissue sarcomas

    International Nuclear Information System (INIS)

    Hirano, Toru; Iwasaki, Katsuro; Suzuki, Ryohei; Monzen, Yoshio; Hombo, Zenichiro

    1989-01-01

    The correlation between the effectiveness of radiation therapy and the histology of soft tissue sarcomas was investigated. Of 31 cases with a soft tissue sarcoma of an extremity treated by conservative surgery and postoperative radiation of 3,000-6,000 cGy, local recurrence occurred in 12; 5 out of 7 synovial sarcomas, 4 of 9 MFH, one of 8 liposarcomas, none of 4 rhabdomyosarcomas and 2 of 3 others. As for the histological subtyping, the 31 soft tissue sarcomas were divided into spindle cell, pleomorphic cell, myxoid and round cell type, and recurrence rates were 75%, 33.3%, 16.7% and 0%, respectively. From the remarkable difference in recurrent rate, it was suggested that round cell and myxoid type of soft tissue sarcomas showed a high radiosensitivity compared to the spindle cell type with low sensitivity. Clarifying the degree of radiosensitivity is helpful in deciding on the management of limb salvage in soft tissue sarcomas of an extremity. (author)

  7. Multiphoton tomography for tissue engineering

    Science.gov (United States)

    König, Karsten

    2008-02-01

    Femtosecond laser multiphoton tomography has been employed in the field of tissue engineering to perform 3D high-resolution imaging of the extracellular matrix proteins elastin and collagen as well as of living cells without any fixation, slicing, and staining. Near infrared 80 MHz picojoule femtosecond laser pulses are able to excite the endogenous fluorophores NAD(P)H, flavoproteins, melanin, and elastin via a non-resonant two-photon excitation process. In addition, collagen can be imaged by second harmonic generation. Using a two-PMT detection system, the ratio of elastin to collagen was determined during optical sectioning. A high submicron spatial resolution and 50 picosecond temporal resolution was achieved using galvoscan mirrors and piezodriven focusing optics as well as a time-correlated single photon counting module with a fast microchannel plate detector and fast photomultipliers. Multiphoton tomography has been used to optimize the tissue engineering of heart valves and vessels in bioincubators as well as to characterize artificial skin. Stem cell characterization and manipulation are of major interest for the field of tissue engineering. Using the novel sub-20 femtosecond multiphoton nanoprocessing laser microscope FemtOgene, the differentiation of human stem cells within spheroids has been in vivo monitored with submicron resolution. In addition, the efficient targeted transfection has been demonstrated. Clinical studies on the interaction of tissue-engineered products with the natural tissue environment can be performed with in vivo multiphoton tomograph DermaInspect.

  8. Bone tissue engineering in osteoporosis.

    Science.gov (United States)

    Jakob, Franz; Ebert, Regina; Ignatius, Anita; Matsushita, Takashi; Watanabe, Yoshinobu; Groll, Juergen; Walles, Heike

    2013-06-01

    Osteoporosis is a polygenetic, environmentally modifiable disease, which precipitates into fragility fractures of vertebrae, hip and radius and also confers a high risk of fractures in accidents and trauma. Aging and the genetic molecular background of osteoporosis cause delayed healing and impair regeneration. The worldwide burden of disease is huge and steadily increasing while the average life expectancy is also on the rise. The clinical need for bone regeneration applications, systemic or in situ guided bone regeneration and bone tissue engineering, will increase and become a challenge for health care systems. Apart from in situ guided tissue regeneration classical ex vivo tissue engineering of bone has not yet reached the level of routine clinical application although a wealth of scaffolds and growth factors has been developed. Engineering of complex bone constructs in vitro requires scaffolds, growth and differentiation factors, precursor cells for angiogenesis and osteogenesis and suitable bioreactors in various combinations. The development of applications for ex vivo tissue engineering of bone faces technical challenges concerning rapid vascularization for the survival of constructs in vivo. Recent new ideas and developments in the fields of bone biology, materials science and bioreactor technology will enable us to develop standard operating procedures for ex vivo tissue engineering of bone in the near future. Once prototyped such applications will rapidly be tailored for compromised conditions like vitamin D and sex hormone deficiencies, cellular deficits and high production of regeneration inhibitors, as they are prevalent in osteoporosis and in higher age. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Adipose tissue oxygenation: Effects on metabolic function

    OpenAIRE

    Hodson, Leanne

    2013-01-01

    With the increasing prevalence of obesity there is a concomitant increase in white adipose tissue dysfunction, with the tissue moving toward a proinflammatory phenotype. Adipose tissue hypoxia has been proposed as a key underlying mechanism triggering tissue dysfunction but data from human, in vivo studies, to support this hypothesis is limited. Human adipose tissue oxygenation has been investigated by direct assessment of tissue oxygen tension (pO2) or by expression of hypoxia-sensitive gene...

  10. Engineered Muscle Actuators: Cells and Tissues

    National Research Council Canada - National Science Library

    Dennis, Robert G; Herr, Hugh; Parker, Kevin K; Larkin, Lisa; Arruda, Ellen; Baar, Keith

    2007-01-01

    .... Our primary objectives were to engineer living skeletal muscle actuators in culture using integrated bioreactors to guide tissue development and to maintain tissue contractility, to achieve 50...

  11. Micro- and nanotechnology in cardiovascular tissue engineering

    International Nuclear Information System (INIS)

    Zhang Boyang; Xiao Yun; Hsieh, Anne; Thavandiran, Nimalan; Radisic, Milica

    2011-01-01

    While in nature the formation of complex tissues is gradually shaped by the long journey of development, in tissue engineering constructing complex tissues relies heavily on our ability to directly manipulate and control the micro-cellular environment in vitro. Not surprisingly, advancements in both microfabrication and nanofabrication have powered the field of tissue engineering in many aspects. Focusing on cardiac tissue engineering, this paper highlights the applications of fabrication techniques in various aspects of tissue engineering research: (1) cell responses to micro- and nanopatterned topographical cues, (2) cell responses to patterned biochemical cues, (3) controlled 3D scaffolds, (4) patterned tissue vascularization and (5) electromechanical regulation of tissue assembly and function.

  12. Tissue transplantation in plastic surgery.

    Science.gov (United States)

    Siemionow, Maria; Agaoglu, Galip

    2007-04-01

    The functional and aesthetic outcome following application of conventional reconstructive procedures or prosthetic materials is not satisfactory, especially in patients who have severe deformities and disabilities. Since the first successful hand transplantation in France in 1998, composite tissue allograft transplantation has gained a great deal of interest in the field of plastic surgery. It is obvious that composite tissue allograft transplantation will improve patients' life quality, but this might be at the expense of decreasing life expectancy. Currently, the main obstacle for composite tissue allograft transplantation is the use of life-long immunosuppression therapy because of their well-known side effects. In addition, the ethical, social, and psychologic issues are raised when discussing face transplantation. The long-term results of the recently performed partial face transplantations will be critical to judge the future applications of partial or total face transplantation.

  13. Tissue Friendly Pendulum: Soft Liner to prevent Tissue Irritation

    Directory of Open Access Journals (Sweden)

    Siddharth Shashidhar Revankar

    2014-01-01

    Full Text Available Palatal mucosal irritation is commonly encountered with the Pendulum appliance. The efficiency of soft liners in reducing tissue irritation has been well documented in the field of prosthodontics. The following article describes an innovative technique where soft liner can be used to reduce palatal mucosal irritation caused by pendulum appliance.

  14. Orbital soft-tissue trauma.

    Science.gov (United States)

    Chazen, J Levi; Lantos, Joshua; Gupta, Ajay; Lelli, Gary J; Phillips, C Douglas

    2014-08-01

    In the clinical assessment of orbital trauma, visual acuity and extraocular muscle motility are critical for rapid evaluation of injury severity. However, assessment of these parameters may be limited by edema and concomitant injuries. Imaging may further delineate the trauma pattern and extent of injury. This review focuses on orbital soft-tissue injuries that can exist with or without orbital fracture. Imaging techniques and soft-tissue injuries, including those involving the anterior chamber, iris and ciliary body, lens, globe, posterior segment, and optic nerve, are reviewed, in addition to intraocular foreign bodies and cavernous-carotid fistulas. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Advances in Meniscal Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Umile Giuseppe Longo

    2012-01-01

    Full Text Available Meniscal tears are the most common knee injuries and have a poor ability of healing. In the last few decades, several techniques have been increasingly used to optimize meniscal healing. Current research efforts of tissue engineering try to combine cell-based therapy, growth factors, gene therapy, and reabsorbable scaffolds to promote healing of meniscal defects. Preliminary studies did not allow to draw definitive conclusions on the use of these techniques for routine management of meniscal lesions. We performed a review of the available literature on current techniques of tissue engineering for the management of meniscal tears.

  16. Injectable gels for tissue engineering.

    Science.gov (United States)

    Gutowska, A; Jeong, B; Jasionowski, M

    2001-08-01

    Recently, tissue engineering approaches using injectable, in situ gel forming systems have been reported. In this review, the gelation processes and several injectable systems that exhibit in situ gel formation at physiological conditions are discussed. Applications of selected injectable systems (alginate, chitosan, hyaluronan, polyethylene oxide/polypropylene oxide) in tissue engineering are also described. Injectable polymer formulation can gel in vivo in response to temperature change (thermal gelation), pH change, ionic cross-linking, or solvent exchange. Kinetics of gelation is directly affected by its mechanism. Injectable formulations offer specific advantages over preformed scaffolds such as: possibility of a minimally invasive implantation, an ability to fill a desired shape, and easy incorporation of various therapeutic agents. Several factors need to be considered before an injectable gel can be selected as a candidate for tissue engineering applications. Apart from tissue-specific cell-matrix interactions, the following gel properties need to be considered: gelation kinetics, matrix resorption rate, possible toxicity of degradation products and their elimination routes, and finally possible interference of the gel matrix with histogenesis. Copyright 2001 Wiley-Liss, Inc.

  17. Frenotomy and keratinized tissue augmentation.

    Science.gov (United States)

    Peacock, M E

    1998-01-01

    Aberrant frenula can be an important etiological factor in progressive gingival recession. When separating or removing frenula, augmentation with keratinized tissue is the treatment of choice in most circumstances. A case is described as a mandibular labial frenotomy in combination with a free gingival graft.

  18. White adipose tissue: Getting nervous

    NARCIS (Netherlands)

    Fliers, E.; Kreier, F.; Voshol, P. J.; Havekes, L. M.; Sauerwein, H. P.; Kalsbeek, A.; Buijs, R. M.; Romijn, J. A.

    2003-01-01

    Neuroendocrine research has altered the traditional perspective of white adipose tissue (WAT) as a passive store of triglycerides. In addition to fatty acids, WAT produces many hormones and can therefore be designated as a traditional endocrine gland actively participating in the integrative

  19. Gradient polymers for tissue engineering

    NARCIS (Netherlands)

    Klein Gunnewiek, Michel

    2015-01-01

    With increasing life expectancy, there is an constant demand for finding solutions to restore damaged or diseased tissues and organs. Regenerative medicine holds the promise to create continuous body-part replacements through the combination of cells, biological factors, and synthetic scaffolds.

  20. Epigenetics in plant tissue culture

    NARCIS (Netherlands)

    Smulders, M.J.M.; Klerk, de G.J.M.

    2011-01-01

    Plants produced vegetatively in tissue culture may differ from the plants from which they have been derived. Two major classes of off-types occur: genetic ones and epigenetic ones. This review is about epigenetic aberrations. We discuss recent studies that have uncovered epigenetic modifications at

  1. Platelets, inflammation and tissue regeneration.

    Science.gov (United States)

    Nurden, Alan T

    2011-05-01

    Blood platelets have long been recognised to bring about primary haemostasis with deficiencies in platelet production and function manifesting in bleeding while upregulated function favourises arterial thrombosis. Yet increasing evidence indicates that platelets fulfil a much wider role in health and disease. First, they store and release a wide range of biologically active substances including the panoply of growth factors, chemokines and cytokines released from a-granules. Membrane budding gives rise to microparticles (MPs), another active participant within the blood stream. Platelets are essential for the innate immune response and combat infection (viruses, bacteria, micro-organisms). They help maintain and modulate inflammation and are a major source of pro-inflammatory molecules (e.g. P-selectin, tissue factor, CD40L, metalloproteinases). As well as promoting coagulation, they are active in fibrinolysis; wound healing, angiogenesis and bone formation as well as in maternal tissue and foetal vascular remodelling. Activated platelets and MPs intervene in the propagation of major diseases. They are major players in atherosclerosis and related diseases, pathologies of the central nervous system (Alzheimers disease, multiple sclerosis), cancer and tumour growth. They participate in other tissue-related acquired pathologies such as skin diseases and allergy, rheumatoid arthritis, liver disease; while, paradoxically, autologous platelet-rich plasma and platelet releasate are being used as an aid to promote tissue repair and cellular growth. The above mentioned roles of platelets are now discussed.

  2. Fundamentals of bladder tissue engineering

    African Journals Online (AJOL)

    W. Mahfouz

    promote angiogenesis and neurogenesis of the regenerated organs. The choice of the scaffold and the type of cells is a crucial and fundamental step in regenerative medicine. In this review article, we demonstrated these three crucial factors of bladder tissue engineering, with the pros and cons of each scaffold type and.

  3. History of plant tissue culture.

    Science.gov (United States)

    Thorpe, Trevor

    2012-01-01

    Plant tissue culture, or the aseptic culture of cells, tissues, organs, and their components under defined physical and chemical conditions in vitro, is an important tool in both basic and applied studies as well as in commercial application. It owes its origin to the ideas of the German scientist, Haberlandt, at the beginning of the twentieth century. The early studies led to root cultures, embryo cultures, and the first true callus/tissue cultures. The period between the 1940s and the 1960s was marked by the development of new techniques and the improvement of those that were already in use. It was the availability of these techniques that led to the application of tissue culture to five broad areas, namely, cell behavior (including cytology, nutrition, metabolism, morphogenesis, embryogenesis, and pathology), plant modification and improvement, pathogen-free plants and germplasm storage, clonal propagation, and product (mainly secondary metabolite) formation, starting in the mid-1960s. The 1990s saw continued expansion in the application of the in vitro technologies to an increasing number of plant species. Cell cultures have remained an important tool in the study of basic areas of plant biology and biochemistry and have assumed major significance in studies in molecular biology and agricultural biotechnology in the twenty-first century. The historical development of these in vitro technologies and their applications is the focus of this chapter.

  4. Biomaterials in myocardial tissue engineering

    Science.gov (United States)

    Reis, Lewis A.; Chiu, Loraine L. Y.; Feric, Nicole; Fu, Lara; Radisic, Milica

    2016-01-01

    Cardiovascular disease is the leading cause of death in the developed world, and as such there is a pressing need for treatment options. Cardiac tissue engineering emerged from the need to develop alternate sources and methods of replacing tissue damaged by cardiovascular diseases, as the ultimate treatment option for many who suffer from end-stage heart failure is a heart transplant. In this review we focus on biomaterial approaches to augment injured or impaired myocardium with specific emphasis on: the design criteria for these biomaterials; the types of scaffolds—composed of natural or synthetic biomaterials, or decellularized extracellular matrix—that have been used to develop cardiac patches and tissue models; methods to vascularize scaffolds and engineered tissue, and finally injectable biomaterials (hydrogels)designed for endogenous repair, exogenous repair or as bulking agents to maintain ventricular geometry post-infarct. The challenges facing the field and obstacles that must be overcome to develop truly clinically viable cardiac therapies are also discussed. PMID:25066525

  5. Histopathology of mucosa-associated lymphoid tissue

    NARCIS (Netherlands)

    Kuper, C.F.

    2006-01-01

    Mucosa-associated lymphoid tissue (MALT) is a generalized term incorporating a disseminated collection of lymphoid tissues in multiple sites throughout the body. MALT sites that have been/are primarily studied include bronchus-associated lymphoid tissue (BALT), gut-associated lymphoid tissue (GALT),

  6. 21 CFR 878.4010 - Tissue adhesive.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tissue adhesive. 878.4010 Section 878.4010 Food... DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4010 Tissue adhesive. (a) Tissue adhesive for the topical approximation of skin—(1) Identification. A tissue adhesive for the topical...

  7. Biomechanics and mechanobiology in functional tissue engineering

    Science.gov (United States)

    Guilak, Farshid; Butler, David L.; Goldstein, Steven A.; Baaijens, Frank P.T.

    2014-01-01

    The field of tissue engineering continues to expand and mature, and several products are now in clinical use, with numerous other preclinical and clinical studies underway. However, specific challenges still remain in the repair or regeneration of tissues that serve a predominantly biomechanical function. Furthermore, it is now clear that mechanobiological interactions between cells and scaffolds can critically influence cell behavior, even in tissues and organs that do not serve an overt biomechanical role. Over the past decade, the field of “functional tissue engineering” has grown as a subfield of tissue engineering to address the challenges and questions on the role of biomechanics and mechanobiology in tissue engineering. Originally posed as a set of principles and guidelines for engineering of load-bearing tissues, functional tissue engineering has grown to encompass several related areas that have proven to have important implications for tissue repair and regeneration. These topics include measurement and modeling of the in vivo biomechanical environment; quantitative analysis of the mechanical properties of native tissues, scaffolds, and repair tissues; development of rationale criteria for the design and assessment of engineered tissues; investigation of the effects biomechanical factors on native and repair tissues, in vivo and in vitro; and development and application of computational models of tissue growth and remodeling. Here we further expand this paradigm and provide examples of the numerous advances in the field over the past decade. Consideration of these principles in the design process will hopefully improve the safety, efficacy, and overall success of engineered tissue replacements. PMID:24818797

  8. Postgraduate programme in tissue banking

    International Nuclear Information System (INIS)

    Yongyudh Vajaradul

    1999-01-01

    In 1992 in the Project Formulation Meeting of IAEA, the masters degree programme was proposed by Dr. Youngyudh Vajaradul, Thailand to upgrade the personnel of tissue bank and the person who had been working and involving in tissue banking. After The Bangkok Biomaterial Center proposed the degree programme and presented to Mahidol University, this programme was accepted by Ministry of University Affairs in 1998 and the masters degree programme under the name of 'Masters of Science in Biomaterial for Implantation' will be started in April 1999. IAEA will support the fellowship candidates from the region to study in masters degree programme. The programme includes 6 months of course work in Bangkok that is 12 credits and 24 is for the dissertation work which would be done in any country. The time of validity is 5 years

  9. Periodontal tissue damage in smokers

    Directory of Open Access Journals (Sweden)

    Hutojo Djajakusuma

    2006-09-01

    Full Text Available Dental plaque is the primary etiological factor in periodontal diseases. However, there are many factors that can modify how an individual periodontal tissue will respond to the accumulation of dental plaque. Among such risk factors, there is increasing evidence that smoking tobacco products alters the expression and rate of progression of periodontal diseases. The aim of this study was to find out the loss of periodontal tissue adhesion in smokers by measuring pocket depth using probe, and by measuring alveolar bone damage using Bone Loss Score (BLS radiographic methods on teeth 12, 11, 21, 22, 32, 31, 41, 42. Based on T Test statistical analysis, there were significant differences in pocket depth damage of alveolar bone in smokers and non smokers. In conclusion there were increasing pocket depth and alveolar bone damage in smokers.

  10. Heterotopic pancreatic tissue in gallbladder

    Directory of Open Access Journals (Sweden)

    Aylhin Joana Lopez Marcano

    2016-12-01

    Full Text Available The heterotopic pancreas (PH is the atypical presence of pancreatic tissue without any anatomic or vascular continuity with the pancreas. PH is a rare condition that can be observed at any level of the gastrointestinal tract and even in other organs. Histopathological characterization of PH allows surgeons to distinguish it from other lesions. Although it is usually a benign and asymptomatic disease, it can occasionally cause complications (obstruction, hemorrhage, inflammation, or malignant transformation. In conclusion, localization in the gallbladder in the few cases of PH is very rare. We present two cases in which, after cholecystectomy indicated by other causes, in the pathological study of the surgical specimen, type 2 pancreatic tissue was found according to the Heinrich classification. [Arch Clin Exp Surg 2016; 5(4.000: 250-253

  11. Fluorescence diagnosis in tissue injury

    Science.gov (United States)

    Maciel, Vitória H.; Ferreira, Juliana; Bagnato, Vanderlei S.

    2009-06-01

    Background and Objectives: The paper aim was to evaluate the efficacy of the fluorescence spectroscopy in the detection of UV-induced skin change of Wistar rats. Study Design/ Materials and Methods: In a group male Wistar rats, the skin damage was produced by an UV-C lamp, periodically monitored using the laser-induced fluorescence, until complete healing process. After determining a characteristic emission band present in the fluorescence spectra of the induced injuries, the amplitude band monitoring allowed the follow up on the injury and the recovery. Results: We observed the appearance of two new emission bands more evident at the injury spectra when compared to the spectrums from normal non-exposed tissue. Following such spectral bands was possible to observe the establishment and recovery. Conclusions: The fluorescence spectroscopy is a promising technique in distinguishing between normal and UV induced skin change helping the evaluation of changes which are irreversible cancer tissue characteristics.

  12. Skin and soft tissue infection.

    Science.gov (United States)

    Sharma, S; Verma, K K

    2001-07-01

    Abstract. Normal skin is heavily colonized by bacterial flora. The most common are the various nonpathogenic gram-positive bacteria such as Staphylococcus epidermidis (coagulase-negative). Skin and soft tissue infections are usually caused by Staphylococcus aureus (S. aureus) and Streptococcus pyogenes. This article discusses common and some not so common bacterial skin infections, including impetigo, folliculitis, furncles and carbuncles, cellulitis and erysipelas, gangrenous cellulitis, staphylococcal scalded skin syndrome and scarlet fever. Impetigo and ecthyma are common bacterial infections of the skin commonly caused by S. aureus and / or Group A streptoccus. In mild and localized impetigo topical antibiotics whereas in widespread or severe one and in ecthyma systemic antibiotics like, cloxacillin, erythromycin, azithromycin or cephalexin should be used. Folliculitis, furunculosis and carbuncle are folliculocentric infections caused by S. aureus involving the variable depth and extent of the follicle(s) and surrounding tissue. These conditions can be treated with topical or systemic antibiotics like cloxacillin, cephalexin, erythromycin, amoxicillin/clavulanic acid or vancomycin. Staphylococcal scalded skin syndrome is a toxin mediated exfoliative dermatosis caused by S. aureus of phase group II. Intravenous penicillinase-resistant anti-staphylococcal antibiotics like methicillin, cloxacillin, cephalosporin or erythromycin are required. Erysipelas and cellulitis are acute infections of dermal and subcutaneous tissues caused most frequently by Group A beta-hemolytic streptococci (erysipelas) or S. aureus requiring systemic antibiotics like oral or intravenous penicillin, erythromycin, cephalexin, cloxacillin, vacomycin, minocycline or ciprofloxacin depending upon the severity, suspected causative organism and culture/sensitivity results. Gangrenous cellulitis is characterized by infection with necrosis of skin and underlying subcutaneous tissue due to various

  13. Quality assurance in tissue banking

    International Nuclear Information System (INIS)

    Von Versen, R.; Mnig, H. J.; Bettin, D.

    1999-01-01

    Today the different kinds of human allografts have the full acceptance for the clinical application for the treatment of a very wide range of indications in many medical disciplines. An essential aspect of this acceptance of these allografts is the complete biological safety, first of all the exclusion of virus contaminations. The German Institute for Cell and Tissue Replacement (DIZG) is functioning as a national tissue bank cooperating with more than 300 hospitals in Germany and Austria. Its profile is determined by the processing of tissue allografts like cortical and cancellous bone, fascia lata, tendon as well as skin, skin substitutes and cultured autologous and allogenic kerytinocytes. DIZG is licensed by the German Federal Institute for Pharmaceuticals and Medical Products and the country health authorities. To ensure that the allografts fulfill the highest quality requirements a controlled and certified quality management system has been established. In accordance with the Good Manufacturing Practice all procedures are perform-ned on the basis of validated methods. All non-vital allografts are sterilized by a chemical sterilisation method with peracetic acid (PAA) that is validated by the Robert Koch Institute, an independent governmental institution, for the inactivation of bacteria, fungi and viruses. The used test viruses are Pseudorabies V, Polio V, Bovine Virusdiarrhoe V, Parvo V, Hepatitis A V, HIV). The DIZG quality management system (QMS) is based on ISO 9001 which is required for institutions that are involved in processing, research and education and is certified by an international auditing body. With this presentation the validation design shall be introduced and the responsibility of regional and national tissue banks for internal and external quality control and quality assurance shall be discussed

  14. Endoscopic tissue diagnosis of cholangiocarcinoma.

    LENUS (Irish Health Repository)

    Harewood, Gavin C

    2008-09-01

    The extremely poor outcome in patients with cholangiocarcinoma, in large part, reflects the late presentation of these tumors and the challenging nature of establishing a tissue diagnosis. Establishing a diagnosis of cholangiocarcinoma requires obtaining evidence of malignancy from sampling of the epithelium of the biliary tract, which has proven to be challenging. Although endoscopic ultrasound-guided fine needle aspiration performs slightly better than endoscopic retrograde cholangiopancreatography in diagnosing cholangiocarcinoma, both endoscopic approaches demonstrate disappointing performance characteristics.

  15. Tissue regeneration the material enablers

    OpenAIRE

    Marsh, George

    2001-01-01

    The potential rewards are well worth the effort. Estimates in the US put the number of patients on transplant waiting lists at over 75,000. Recent figures from the United Network for Organ Sharing indicate that around 5% of these die while waiting for a transplant organ to become available. Interest and investment levels are high—the US National Institute of Standards and Technology's Advanced Technology Program has poured millions of dollars into tissue engineering product development and th...

  16. Aroma production by tissue cultures.

    Science.gov (United States)

    Hrazdina, G

    2006-02-22

    Although plant tissue cultures have been in use for the past hundred years, adapting them for the production of aroma compounds started only in the 1970s. The use of tissue cultures in aroma production has its advantages, because plant cells, unlike whole plants, are not limited to geographic locations or the seasons. Cell mass can be doubled relatively rapidly and can be induced for the production of compounds in a coordinated manner. Compounds can be isolated from cells or the medium with relative ease. Therefore, it would seem to be ideal to use plant cell cultures for the production of aroma compounds. Cell cultures, however, also have some problems. The production of aroma compounds or their precursors is in relatively low amounts, and thus this production method is expensive. Additional expenses are the cost of the medium and the purification of the compounds for food use. Also, cell cultures can only be used effectively in systems for which the biochemical pathway of the aroma compounds is known. In this paper the results of experiments for the use of tissue cultures in the production of vanilla, raspberry, strawberry garlic, and onion aromas is discussed.

  17. Flocking transitions in confluent tissues.

    Science.gov (United States)

    Giavazzi, Fabio; Paoluzzi, Matteo; Macchi, Marta; Bi, Dapeng; Scita, Giorgio; Manning, M Lisa; Cerbino, Roberto; Marchetti, M Cristina

    2018-04-25

    Collective cell migration in dense tissues underlies important biological processes, such as embryonic development, wound healing and cancer invasion. While many aspects of single cell movements are now well established, the mechanisms leading to displacements of cohesive cell groups are still poorly understood. To elucidate the emergence of collective migration in mechanosensitive cells, we examine a self-propelled Voronoi (SPV) model of confluent tissues with an orientational feedback that aligns a cell's polarization with its local migration velocity. While shape and motility are known to regulate a density-independent liquid-solid transition in tissues, we find that aligning interactions facilitate collective motion and promote solidification, with transitions that can be predicted by extending statistical physics tools such as effective temperature to this far-from-equilibrium system. In addition to accounting for recent experimental observations obtained with epithelial monolayers, our model predicts structural and dynamical signatures of flocking, which may serve as gateway to a more quantitative characterization of collective motility.

  18. Adipose Tissue Immunity and Cancer

    Directory of Open Access Journals (Sweden)

    Victoria eCatalan

    2013-10-01

    Full Text Available Inflammation and altered immune response are important components of obesity and contribute greatly to the promotion of obesity-related metabolic complications, especially cancer development. Adipose tissue expansion is associated with increased infiltration of various types of immune cells from both the innate and adaptive immune systems. Thus, adipocytes and infiltrating immune cells secrete proinflammatory adipokines and cytokines providing a microenvironment favourable for tumour growth. Accumulation of B and T cells in adipose tissue precedes macrophage infiltration causing a chronic low-grade inflammation. Phenotypic switching towards M1 macrophages and Th1 T cells constitutes an important mechanism described in the obese state correlating with increased tumour growth risk. Other possible synergic mechanisms causing a dysfunctional adipose tissue include fatty acid-induced inflammation, oxidative stress, endoplasmic reticulum stress, and hypoxia. Recent investigations have started to unravel the intricacy of the cross-talk between tumour cell/immune cell/adipocyte. In this sense, future therapies should take into account the combination of anti-inflammatory approaches that target the tumour microenvironment with more sophisticated and selective anti-tumoural drugs.

  19. Radiation effects on human tissues and their use in tissue banking

    International Nuclear Information System (INIS)

    Edwards, H.E.; Phillips, G.O.

    1983-01-01

    The chemical and physical effects of ionising radiation on animal tissues and tissue components are reviewed. Various aspects of the use of radiation sterilization for human tissues intended for tissue banks are discussed. Reference is made to the IAEA initiative to develop a Human Tissue Bank at the Orthopaedic Hospital, Kemmedine, Burma to train local technical staff. (U.K.)

  20. Tissue/blood partition coefficients for xenon in various adipose tissue depots in man

    DEFF Research Database (Denmark)

    Bülow, J; Jelnes, Rolf; Astrup, A

    1987-01-01

    Tissue/blood partition coefficients (lambda) for xenon were calculated for subcutaneous adipose tissue from the abdominal wall and the thigh, and for the perirenal adipose tissue after chemical analysis of the tissues for lipid, water and protein content. The lambda in the perirenal tissue was fo...

  1. Effect of ionizing radiations on connective tissue

    International Nuclear Information System (INIS)

    Altman, K.I.; Gerber, G.B.

    1980-01-01

    The effects of ionizing radiations on connective tissue in lung, heart, vasculature, kidney, skin, and skeletal tissues are reviewed. Special emphasis is given to the effect of ionizing radiations on vasculo-connective tissue and fibrotic changes following radiation-induced injury to organs and tissues. In order to put the subject matter in proper prospective, the general biochemistry, physiology, and pathology of connective tissue is reviewed briefly together with the participation of connective tissue in disease. The review closes with an assessment of future problems and an enumeration and discussion of important, as yet unanswered questions

  2. Assessment of tissue ingrowth rates in polyurethane scaffolds for tissue engineering

    NARCIS (Netherlands)

    Ramrattan, Navin N.; Heijkants, Ralf G.J.C.; Tienen, Tony G. van; Schouten, Arend Jan; Veth, Rene P.H.; Buma, Pieter; Ramrattan, [No Value

    The continuous development of new biomaterials for tissue engineering and the enhancement of tissue ingrowth into existing scaffolds, using growth factors, create the necessity for developing adequate tools to assess tissue ingrowth rates into porous biomaterials. Current histomorphometric

  3. Tissue culture of ornamental cacti

    Directory of Open Access Journals (Sweden)

    Eugenio Pérez-Molphe-Balch

    2015-12-01

    Full Text Available Cacti species are plants that are well adapted to growing in arid and semiarid regions where the main problem is water availability. Cacti have developed a series of adaptations to cope with water scarcity, such as reduced leaf surface via morphological modifications including spines, cereous cuticles, extended root systems and stem tissue modifications to increase water storage, and crassulacean acid metabolism to reduce transpiration and water loss. Furthermore, seeds of these plants very often exhibit dormancy, a phenomenon that helps to prevent germination when the availability of water is reduced. In general, cactus species exhibit a low growth rate that makes their rapid propagation difficult. Cacti are much appreciated as ornamental plants due to their great variety and diversity of forms and their beautiful short-life flowers; however, due to difficulties in propagating them rapidly to meet market demand, they are very often over-collected in their natural habitats, which leads to numerous species being threatened, endangered or becoming extinct. Therefore, plant tissue culture techniques may facilitate their propagation over a shorter time period than conventional techniques used for commercial purposes; or may help to recover populations of endangered or threatened species for their re-introduction in the wild; or may also be of value to the preservation and conservation of the genetic resources of this important family. Herein we present the state-of-the-art of tissue culture techniques used for ornamental cacti and selected suggestions for solving a number of the problems faced by members of the Cactaceae family.

  4. Tissue Biopsies in Diabetes Research

    DEFF Research Database (Denmark)

    Højlund, Kurt; Gaster, Michael; Beck-Nielsen, Henning

    2007-01-01

    Type 2 diabetes is characterized by insulin resistance in major metabolic tissues such as skeletal muscle, liver and fat cells, and failure of the pancreatic ß-cells to compensate for this abnormality (1,2). Skeletal muscle is the major site of glucose disposal in response to insulin, and insulin....... Together with morphological studies, measurement of energy stores and metabolites, enzyme activity and phosphorylation, gene and protein expression in skeletal muscle biopsies have revealed a variety of cellular abnormalities in patients with type 2 diabetes and prediabetes. The possibility to establish...

  5. Tissue Biopsies in Diabetes Research

    DEFF Research Database (Denmark)

    Højlund, Kurt; Gaster, Michael; Beck-Nielsen, Henning

    2007-01-01

    Type 2 diabetes is characterized by insulin resistance in major metabolic tissues such as skeletal muscle, liver and fat cells, and failure of the pancreatic ß-cells to compensate for this abnormality (1,2). Skeletal muscle is the major site of glucose disposal in response to insulin, and insulin...... description of the technique of percutaneous needle biopsy of skeletal muscle and the establishment of human muscle cell cultures together with a discussion of advantages and limitations of the methods in diabetes research...

  6. Quality control in tissue banking--ensuring the safety of allograft tissues.

    Science.gov (United States)

    Humphries, Linda K; Mansavage, Vicki L

    2006-09-01

    DESPITE FEDERAL REGULATIONS for tissue-banking practices, inadequate quality control led to the largest allograft tissue recall in history in October 2005. THE RECALL INCLUDED all allograft tissues obtained from 761 donors and distributed by five tissue banks. Many of these tissues already had been implanted and were unrecoverable. THIS ARTICLE DESCRIBES the many tissue-banking industry variables, including donor selection and testing and tissue recovery, processing, and preservation. QUESTIONS THAT HEALTH CARE providers can ask to determine which tissue banks' quality control measures best ensure the safety of the allografts they provide also are included.

  7. SE Marine Mammal Histology/Tissue data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Tissue samples are collected from stranded marine mammals in the Southeastern United States. These tissue samples are examined histologically and evaluated to...

  8. Tritium concentration in foods and human tissues

    International Nuclear Information System (INIS)

    Hisamatsu, S.; Takizawa, Y.; Katsumata, T.

    1991-01-01

    Tritium concentrations in diet samples at Akita City, northern Japan, and in human tissue samples from general population in Akita Prefecture were analyzed to study fallout 3 H transfer from diet to human body. The 3 H concentration in free water form as well as that in tissue-bound form were determined separately. The specific activity ratios of tissue bound 3 H to free water 3 H in the diet and human soft tissue samples were found to be close to unity in significant contrast with those reported in Italy and the US during the period of 1970s and early 1980s. The free water 3 H concentrations in human tissues agreed well with those in diet including tap water. Tissue-bound 3 H concentrations in human bone samples were found to be higher than those in the soft tissues, and suggest the longer biological half-life of 3 H in bone than the soft tissues

  9. Method for localizing heating in tumor tissue

    Science.gov (United States)

    Doss, James D.; McCabe, Charles W.

    1977-04-12

    A method for a localized tissue heating of tumors is disclosed. Localized radio frequency current fields are produced with specific electrode configurations. Several electrode configurations are disclosed, enabling variations in electrical and thermal properties of tissues to be exploited.

  10. Stages of Adult Soft Tissue Sarcoma

    Science.gov (United States)

    ... Childhood Vascular Tumors Treatment Research Adult Soft Tissue Sarcoma Treatment (PDQ®)–Patient Version General Information About Adult Soft Tissue Sarcoma Go to Health Professional Version Key Points Adult ...

  11. Treatment Option Overview (Adult Soft Tissue Sarcoma)

    Science.gov (United States)

    ... Childhood Vascular Tumors Treatment Research Adult Soft Tissue Sarcoma Treatment (PDQ®)–Patient Version General Information About Adult Soft Tissue Sarcoma Go to Health Professional Version Key Points Adult ...

  12. General Information about Childhood Soft Tissue Sarcoma

    Science.gov (United States)

    ... Childhood Vascular Tumors Treatment Research Childhood Soft Tissue Sarcoma Treatment (PDQ®)–Patient Version General Information About Childhood Soft Tissue Sarcoma Go to Health Professional Version Key Points Childhood ...

  13. Treatment Options for Adult Soft Tissue Sarcoma

    Science.gov (United States)

    ... Childhood Vascular Tumors Treatment Research Adult Soft Tissue Sarcoma Treatment (PDQ®)–Patient Version General Information About Adult Soft Tissue Sarcoma Go to Health Professional Version Key Points Adult ...

  14. Treatment Option Overview (Childhood Soft Tissue Sarcoma)

    Science.gov (United States)

    ... Childhood Vascular Tumors Treatment Research Childhood Soft Tissue Sarcoma Treatment (PDQ®)–Patient Version General Information About Childhood Soft Tissue Sarcoma Go to Health Professional Version Key Points Childhood ...

  15. General Information about Adult Soft Tissue Sarcoma

    Science.gov (United States)

    ... Childhood Vascular Tumors Treatment Research Adult Soft Tissue Sarcoma Treatment (PDQ®)–Patient Version General Information About Adult Soft Tissue Sarcoma Go to Health Professional Version Key Points Adult ...

  16. Treatment Options for Childhood Soft Tissue Sarcoma

    Science.gov (United States)

    ... Childhood Vascular Tumors Treatment Research Childhood Soft Tissue Sarcoma Treatment (PDQ®)–Patient Version General Information About Childhood Soft Tissue Sarcoma Go to Health Professional Version Key Points Childhood ...

  17. Stages of Childhood Soft Tissue Sarcoma

    Science.gov (United States)

    ... Childhood Vascular Tumors Treatment Research Childhood Soft Tissue Sarcoma Treatment (PDQ®)–Patient Version General Information About Childhood Soft Tissue Sarcoma Go to Health Professional Version Key Points Childhood ...

  18. Drugs Approved for Soft Tissue Sarcoma

    Science.gov (United States)

    ... Your Treatment Research Drugs Approved for Soft Tissue Sarcoma This page lists cancer drugs approved by the ... not listed here. Drugs Approved for Soft Tissue Sarcoma Cosmegen (Dactinomycin) Dactinomycin Doxorubicin Hydrochloride Eribulin Mesylate Gleevec ( ...

  19. Aging changes in organs - tissue - cells

    Science.gov (United States)

    ... the passages inside the body, such as the gastrointestinal system, are made of epithelial tissue. Muscle tissue includes ... including changes in: Hormone production Immunity The skin Sleep Bones, muscles, and joints The breasts The face ...

  20. Biomimetic strategies for engineering composite tissues.

    Science.gov (United States)

    Lee, Nancy; Robinson, Jennifer; Lu, Helen

    2016-08-01

    The formation of multiple tissue types and their integration into composite tissue units presents a frontier challenge in regenerative engineering. Tissue-tissue synchrony is crucial in providing structural support for internal organs and enabling daily activities. This review highlights the state-of-the-art in composite tissue scaffold design, and explores how biomimicry can be strategically applied to avoid over-engineering the scaffold. Given the complexity of biological tissues, determining the most relevant parameters for recapitulating native structure-function relationships through strategic biomimicry will reduce the burden for clinical translation. It is anticipated that these exciting efforts in composite tissue engineering will enable integrative and functional repair of common soft tissue injuries and lay the foundation for total joint or limb regeneration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Modeling oxygen transport in surgical tissue transfer

    OpenAIRE

    Matzavinos, Anastasios; Kao, Chiu-Yen; Green, J. Edward F.; Sutradhar, Alok; Miller, Michael; Friedman, Avner

    2009-01-01

    Reconstructive microsurgery is a clinical technique used to transfer large amounts of a patient's tissue from one location used to another in order to restore physical deformities caused by trauma, tumors, or congenital abnormalities. The trend in this field is to transfer tissue using increasingly smaller blood vessels, which decreases problems associated with tissue harvest but increases the possibility that blood supply to the transferred tissue may not be adequate for healing. It would th...

  2. Photochemical tissue bonding with chitosan adhesive films

    OpenAIRE

    Lauto, Antonio; Mawad, Damia; Barton, Matthew; Gupta, Abhishek; Piller, Sabine C; Hook, James

    2010-01-01

    Abstract Background Photochemical tissue bonding (PTB) is a promising sutureless technique for tissue repair. PTB is often achieved by applying a solution of rose bengal (RB) between two tissue edges, which are irradiated by a green laser to crosslink collagen fibers with minimal heat production. In this study, RB has been incorporated in chitosan films to create a novel tissue adhesive that is laser-activated. Methods Adhesive films, based on chitosan and containing ~0.1 wt% RB were manufact...

  3. Facial sculpting and tissue augmentation.

    Science.gov (United States)

    Carruthers, Jean D A; Carruthers, Alastair

    2005-11-01

    Until recently, deep facial sculpting was exclusively the domain of surgical interventions. Recent advances in the available array of dermal and subdermal fillers combined with an esthetic appreciation by both surgeons and nonsurgeons alike of the positive effect of filling the volume-depleted face have led to an expansion in the indications for the use of soft tissue augmenting agents. Subdermal support of the lateral two-thirds of the brow, the nasojugal fold, the malar and buccal fat pads, the lateral lip commissures, and the perioral region, including the pre-jowl sulcus, all restore youthful facial contour and harmony. An important advance in technique is the subdermal rather than the intradermal injection plane. "Instant" facial sculpting giving a brow-lift, cheek-lift, lip expansion, and perioral augmentation is possible using modern soft tissue augmenting agents. The softer, more relaxed appearance contrasts to the somewhat "pulled" appearance of subjects who have had surgical overcorrections. Treatments can be combined with botulinum toxin and other procedures if required. Newer advances in the use of fillers include the use of fillers injected in the subdermal plane for "lunchtime" facial sculpting. Using the modern esthetic filler compounds, which are biodegradable but longer lasting, subjects can have a "rehearsal" treatment or make it ongoing. Some individuals, such as those with human immunodeficiency virus (HIV)-related lipoatrophy or those who desire to obtain a longer-lasting effect, may elect to use a nonbiodegradable filling agent.

  4. Nanotechnology in bone tissue engineering.

    Science.gov (United States)

    Walmsley, Graham G; McArdle, Adrian; Tevlin, Ruth; Momeni, Arash; Atashroo, David; Hu, Michael S; Feroze, Abdullah H; Wong, Victor W; Lorenz, Peter H; Longaker, Michael T; Wan, Derrick C

    2015-07-01

    Nanotechnology represents a major frontier with potential to significantly advance the field of bone tissue engineering. Current limitations in regenerative strategies include impaired cellular proliferation and differentiation, insufficient mechanical strength of scaffolds, and inadequate production of extrinsic factors necessary for efficient osteogenesis. Here we review several major areas of research in nanotechnology with potential implications in bone regeneration: 1) nanoparticle-based methods for delivery of bioactive molecules, growth factors, and genetic material, 2) nanoparticle-mediated cell labeling and targeting, and 3) nano-based scaffold construction and modification to enhance physicochemical interactions, biocompatibility, mechanical stability, and cellular attachment/survival. As these technologies continue to evolve, ultimate translation to the clinical environment may allow for improved therapeutic outcomes in patients with large bone deficits and osteodegenerative diseases. Traditionally, the reconstruction of bony defects has relied on the use of bone grafts. With advances in nanotechnology, there has been significant development of synthetic biomaterials. In this article, the authors provided a comprehensive review on current research in nanoparticle-based therapies for bone tissue engineering, which should be useful reading for clinicians as well as researchers in this field. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Human tissue in systems medicine.

    Science.gov (United States)

    Caie, Peter D; Schuur, Klaas; Oniscu, Anca; Mullen, Peter; Reynolds, Paul A; Harrison, David J

    2013-12-01

    Histopathology, the examination of an architecturally artefactual, two-dimensional and static image remains a potent tool allowing diagnosis and empirical expectation of prognosis. Considerable optimism exists that the advent of molecular genetic testing and other biomarker strategies will improve or even replace this ancient technology. A number of biomarkers already add considerable value for prediction of whether a treatment will work. In this short review we argue that a systems medicine approach to pathology will not seek to replace traditional pathology, but rather augment it. Systems approaches need to incorporate quantitative morphological, protein, mRNA and DNA data. A significant challenge for clinical implementation of systems pathology is how to optimize information available from tissue, which is frequently sub-optimal in quality and amount, and yet generate useful predictive models that work. The transition of histopathology to systems pathophysiology and the use of multiscale data sets usher in a new era in diagnosis, prognosis and prediction based on the analysis of human tissue. © 2013 The Authors. FEBS Journal published by John Wiley & Sons Ltd on behalf of FEBS.

  6. Leaf hydraulics II: vascularized tissues.

    Science.gov (United States)

    Rockwell, Fulton E; Holbrook, N Michele; Stroock, Abraham D

    2014-01-07

    Current models of leaf hydration employ an Ohm's law analogy of the leaf as an ideal capacitor, neglecting the resistance to flow between cells, or treat the leaf as a plane sheet with a source of water at fixed potential filling the mid-plane, neglecting the discrete placement of veins as well as their resistance. We develop a model of leaf hydration that considers the average conductance of the vascular network to a representative areole (region bounded by the vascular network), and represent the volume of tissue within the areole as a poroelastic composite of cells and air spaces. Solutions to the 3D flow problem are found by numerical simulation, and these results are then compared to 1D models with exact solutions for a range of leaf geometries, based on a survey of temperate woody plants. We then show that the hydration times given by these solutions are well approximated by a sum of the ideal capacitor and plane sheet times, representing the time for transport through the vasculature and tissue respectively. We then develop scaling factors relating this approximate solution to the 3D model, and examine the dependence of these scaling factors on leaf geometry. Finally, we apply a similar strategy to reduce the dimensions of the steady state problem, in the context of peristomatal transpiration, and consider the relation of transpirational gradients to equilibrium leaf water potential measurements. © 2013 Published by Elsevier Ltd. All rights reserved.

  7. Flocking Transition in Confluent Tissues

    Science.gov (United States)

    Paoluzzi, Matteo; Giavazzi, Fabio; Macchi, Marta; Scita, Giorgio; Cerbino, Roberto; Manning, Lisa; Marchetti, Cristina

    The emerging of collective migration in biological tissues plays a pivotal role in embryonic morphogenesis, wound healing and cancer invasion. While many aspects of single cell movements are well established, the mechanisms leading to coherent displacements of cohesive cell groups are still poorly understood. Some of us recently proposed a Self-Propelled Voronoi (SPV) model of dense tissues that combines self-propelled particle models and vertex models of confluent cell layers and exhibits a liquid-solid transition as a function of cell shape and cell motility. We now examine the role of cell polarization on collective cell dynamics by introducing an orientation mechanism that aligns cell polarization with local cell motility. The model predicts a density-independent flocking transition tuned by the strength of the aligning interaction, with both solid and liquid flocking states existing in different regions of parameter space. MP and MCM were supported by the Simons Foundation Targeted Grant in the Mathematical Modeling of Living Systems Number: 342354 and by the Syracuse Soft Matter Program.

  8. Mechanics of needle-tissue interaction

    NARCIS (Netherlands)

    Roesthuis, Roy; van Veen, Youri; Jahya, Alex; Misra, Sarthak

    2011-01-01

    When a needle is inserted into soft tissue, interac- tion forces are developed at the needle tip and along the needle shaft. The needle tip force is due to cutting of the tissue, and the force along the needle shaft is due to friction between needle and tissue. In this study, the friction force is

  9. Scientific and industrial status of tissue engineering ...

    African Journals Online (AJOL)

    Tissue engineering is a newly emerging field targeting many unresolved health problems. So far, the achievements of this technology in the production of different tissue engineered substitutes were promising. This review is intended to describe, briefly and in a simple language, what tissue engineering is, what the ...

  10. Engineering Biology by Controlling Tissue Folding.

    Science.gov (United States)

    Hookway, Tracy A

    2018-04-01

    Achieving complex self-organization in vitro has remained a fundamental challenge in tissue engineering. A recent study in Developmental Cell by Hughes and colleagues uses computational and experimental approaches to understand and control the morphogenic process of tissue folding. These approaches provide an engineering framework to reproducibly control tissue shape. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Advances of radiation sterilisation in tissue banking.

    Science.gov (United States)

    Yusof, Norimah

    2017-10-11

    Under the auspices of the IAEA tissue banking programme on "Radiation Sterilisation of Tissue Graft" conducted from 1985 to 2004, many scientists and surgeons were involved in various regional research and development (R&D) projects mainly in dealing with radiation dose selection, radiation effects on human tissues and quality system in radiation sterilisation. New findings on radiation effects, tissue processing and preservation were shared during the regional and interregional meetings and workshops. Many tissue banks started to use radiation (25 kGy) to sterilize tissue grafts for tissue safety and efficacy and still continue to use it. The IAEA Code of Practice for Radiation Sterilization of Tissues Allografts developed in 2007 offered simpler methods to conduct radiation dose setting and dose validation experiments for tissue grafts. Advances in dose selection and dose mapping are continued under the quality management system when banks need to be certified to continue their operation. The combination of good tissue processing and preservation as well as good radiation practice will ensure the tissue products are properly sterilised thus safe and of high quality. Experience in meeting challenges in using radiation sterilisation and achievements reported by the tissue bankers are shared here.

  12. Scientific and industrial status of tissue engineering

    African Journals Online (AJOL)

    SERVER

    2007-12-28

    Dec 28, 2007 ... Tissue engineering is a newly emerging field targeting many unresolved health problems. So far, the achievements of this technology in the production of different tissue engineered substitutes were promising. This review is intended to describe, briefly and in a simple language, what tissue engineering is ...

  13. Hard-Soft Tissue Interface Engineering.

    Science.gov (United States)

    Armitage, Oliver E; Oyen, Michelle L

    2015-01-01

    The musculoskeletal system is comprised of three distinct tissue categories: structural mineralized tissues, actuating muscular soft tissues, and connective tissues. Where connective tissues - ligament, tendon and cartilage - meet with bones, a graded interface in mechanical properties occurs that allows the transmission of load without creating stress concentrations that would cause tissue damage. This interface typically occurs over less than 1 mm and contains a three order of magnitude difference in elastic stiffness, in addition to changes in cell type and growth factor concentrations among others. Like all engineered tissues, the replication of these interfaces requires the production of scaffolds that will provide chemical and mechanical cues, resulting in biologically accurate cellular differentiation. For interface tissues however, the scaffold must provide spatially graded chemical and mechanical cues over sub millimetre length scales. Naturally, this complicates the manufacture of the scaffolds and every stage of their subsequent cell seeding and growth, as each region has different optimal conditions. Given the higher degree of difficulty associated with replicating interface tissues compared to surrounding homogeneous tissues, it is likely that the development of complex musculoskeletal tissue systems will continue to be limited by the engineering of connective tissues interfaces with bone.

  14. Piezoelectric materials for tissue regeneration: A review.

    Science.gov (United States)

    Rajabi, Amir Hossein; Jaffe, Michael; Arinzeh, Treena Livingston

    2015-09-01

    The discovery of piezoelectricity, endogenous electric fields and transmembrane potentials in biological tissues raised the question whether or not electric fields play an important role in cell function. It has kindled research and the development of technologies in emulating biological electricity for tissue regeneration. Promising effects of electrical stimulation on cell growth and differentiation and tissue growth has led to interest in using piezoelectric scaffolds for tissue repair. Piezoelectric materials can generate electrical activity when deformed. Hence, an external source to apply electrical stimulation or implantation of electrodes is not needed. Various piezoelectric materials have been employed for different tissue repair applications, particularly in bone repair, where charges induced by mechanical stress can enhance bone formation; and in neural tissue engineering, in which electric pulses can stimulate neurite directional outgrowth to fill gaps in nervous tissue injuries. In this review, a summary of piezoelectricity in different biological tissues, mechanisms through which electrical stimulation may affect cellular response, and recent advances in the fabrication and application of piezoelectric scaffolds will be discussed. The discovery of piezoelectricity, endogenous electric fields and transmembrane potentials in biological tissues has kindled research and the development of technologies using electrical stimulation for tissue regeneration. Piezoelectric materials generate electrical activity in response to deformations and allow for the delivery of an electrical stimulus without the need for an external power source. As a scaffold for tissue engineering, growing interest exists due to its potential of providing electrical stimulation to cells to promote tissue formation. In this review, we cover the discovery of piezoelectricity in biological tissues, its connection to streaming potentials, biological response to electrical stimulation and

  15. Biomechanics and mechanobiology in functional tissue engineering.

    Science.gov (United States)

    Guilak, Farshid; Butler, David L; Goldstein, Steven A; Baaijens, Frank P T

    2014-06-27

    The field of tissue engineering continues to expand and mature, and several products are now in clinical use, with numerous other preclinical and clinical studies underway. However, specific challenges still remain in the repair or regeneration of tissues that serve a predominantly biomechanical function. Furthermore, it is now clear that mechanobiological interactions between cells and scaffolds can critically influence cell behavior, even in tissues and organs that do not serve an overt biomechanical role. Over the past decade, the field of "functional tissue engineering" has grown as a subfield of tissue engineering to address the challenges and questions on the role of biomechanics and mechanobiology in tissue engineering. Originally posed as a set of principles and guidelines for engineering of load-bearing tissues, functional tissue engineering has grown to encompass several related areas that have proven to have important implications for tissue repair and regeneration. These topics include measurement and modeling of the in vivo biomechanical environment; quantitative analysis of the mechanical properties of native tissues, scaffolds, and repair tissues; development of rationale criteria for the design and assessment of engineered tissues; investigation of the effects biomechanical factors on native and repair tissues, in vivo and in vitro; and development and application of computational models of tissue growth and remodeling. Here we further expand this paradigm and provide examples of the numerous advances in the field over the past decade. Consideration of these principles in the design process will hopefully improve the safety, efficacy, and overall success of engineered tissue replacements. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Hardwiring Stem Cell Communication through Tissue Structure.

    Science.gov (United States)

    Xin, Tianchi; Greco, Valentina; Myung, Peggy

    2016-03-10

    Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function, but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Hardwiring stem cell communication through tissue structure

    Science.gov (United States)

    Xin, Tianchi; Greco, Valentina; Myung, Peggy

    2016-01-01

    Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. PMID:26967287

  18. Quality system in Malaysian National Tissue Bank

    International Nuclear Information System (INIS)

    Go Boon Thong; Firdaus, M. N.; Abd Rani Shamsudin

    1999-01-01

    Quality System in Malaysian National Tissue Bank is based on the Quality Manual which has been drawn up by the chairman, who is the Dean, School of Medical Sciences. The Quality Manual include general standard for Tissue Banking in University Science of Malaysia which describe and explain a set of general standard similar to the EATB standard. The primary aim of the quality system is to produce a safe and effective tissue graft for successful clinical use and to ensure the safety of tissue bank operators. The Quality Manual also related the role of a Technical Manual, which explain the standard of technical aspect of tissue bank in a Quality Assurance. The safe working environment and Good Laboratory Practice is highlight in Quality System. Documentation of tissue bank activities is the key to the administration to tissue bank. Finally Quality System in tissue banking will never be complete without a Tissue Bank Auditing System which allow the tissue bank coordinator and staff to look into the problem and further enhance the progress of the tissue bank

  19. Mechanics of epithelial tissue homeostasis and morphogenesis.

    Science.gov (United States)

    Guillot, Charlène; Lecuit, Thomas

    2013-06-07

    Epithelia are robust tissues that support the structure of embryos and organs and serve as effective barriers against pathogens. Epithelia also chemically separate different physiological environments. These vital functions require tight association between cells through the assembly of junctions that mechanically stabilize the tissue. Remarkably, epithelia are also dynamic and can display a fluid behavior. Cells continuously die or divide, thereby allowing functional tissue homeostasis. Epithelial cells can change shape or intercalate as tissues deform during morphogenesis. We review the mechanical basis of tissue robustness and fluidity, with an emphasis on the pivotal role of junction dynamics. Tissue fluidity emerges from local active stresses acting at cell interfaces and allows the maintenance of epithelial organization during morphogenesis and tissue renewal.

  20. Depth-resolved fluorescence of biological tissue

    Science.gov (United States)

    Wu, Yicong; Xi, Peng; Cheung, Tak-Hong; Yim, So Fan; Yu, Mei-Yung; Qu, Jianan Y.

    2005-06-01

    The depth-resolved autofluorescence ofrabbit oral tissue, normal and dysplastic human ectocervical tissue within l20μm depth were investigated utilizing a confocal fluorescence spectroscopy with the excitations at 355nm and 457nm. From the topmost keratinizing layer of oral and ectocervical tissue, strong keratin fluorescence with the spectral characteristics similar to collagen was observed. The fluorescence signal from epithelial tissue between the keratinizing layer and stroma can be well resolved. Furthermore, NADH and FADfluorescence measured from the underlying non-keratinizing epithelial layer were strongly correlated to the tissue pathology. This study demonstrates that the depth-resolved fluorescence spectroscopy can reveal fine structural information on epithelial tissue and potentially provide more accurate diagnostic information for determining tissue pathology.

  1. Calculation of neutron kerma in tissues

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H.R.; Manzanares A, E. [Unidades Academicas de Estudios Nucleares, Ing. Electrica y Matematicas, Universidad Autonoma de Zacatecas, A.P. 336, 98000 Zacatecas (Mexico)]. E-mail: rvega@cantera.reduaz.mx

    2004-07-01

    Neutron kerma of normal and tumor tissues has been calculated using the tissues elemental concentration. A program developed in Math cad contains the kerma factors of C, H, O, N, Na, Mg, P, S, Cl, K, etc. that are in normal and tumor human tissues. Having the elemental composition of any human tissue the neutron kerma can be calculated. The program was tested using the elemental composition of tumor tissues such as sarcoma, melanoma, carcinoma and adenoid cystic, also neutron kerma for adipose and muscle tissue for normal adult was calculated. The results are in agreement with those published in literature. The neutron kerma for water was also calculated because in some dosimetric calculations water is used to describe normal and tumor tissues. From this comparison was found that at larger energies kerma factors are approximately the same, but energies less than 100 eV the differences are large. (Author)

  2. Calculation of neutron kerma in tissues

    International Nuclear Information System (INIS)

    Vega C, H.R.; Manzanares A, E.

    2004-01-01

    Neutron kerma of normal and tumor tissues has been calculated using the tissues elemental concentration. A program developed in Math cad contains the kerma factors of C, H, O, N, Na, Mg, P, S, Cl, K, etc. that are in normal and tumor human tissues. Having the elemental composition of any human tissue the neutron kerma can be calculated. The program was tested using the elemental composition of tumor tissues such as sarcoma, melanoma, carcinoma and adenoid cystic, also neutron kerma for adipose and muscle tissue for normal adult was calculated. The results are in agreement with those published in literature. The neutron kerma for water was also calculated because in some dosimetric calculations water is used to describe normal and tumor tissues. From this comparison was found that at larger energies kerma factors are approximately the same, but energies less than 100 eV the differences are large. (Author)

  3. Radiotherapy in patients with connective tissue diseases.

    Science.gov (United States)

    Giaj-Levra, Niccolò; Sciascia, Savino; Fiorentino, Alba; Fersino, Sergio; Mazzola, Rosario; Ricchetti, Francesco; Roccatello, Dario; Alongi, Filippo

    2016-03-01

    The decision to offer radiotherapy in patients with connective tissue diseases continues to be challenging. Radiotherapy might trigger the onset of connective tissue diseases by increasing the expression of self-antigens, diminishing regulatory T-cell activity, and activating effectors of innate immunity (dendritic cells) through Toll-like receptor-dependent mechanisms, all of which could potentially lead to breaks of immune tolerance. This potential risk has raised some debate among radiation oncologists about whether patients with connective tissue diseases can tolerate radiation as well as people without connective tissue diseases. Because the number of patients with cancer and connective tissue diseases needing radiotherapy will probably increase due to improvements in medical treatment and longer life expectancy, the issue of interactions between radiotherapy and connective tissue diseases needs to be clearer. In this Review, we discuss available data and evidence for patients with connective tissue diseases treated with radiotherapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Tissue engineering of cartilages using biomatrices

    DEFF Research Database (Denmark)

    Melrose, J.; Chuang, C.; Whitelock, J.

    2008-01-01

    Tissue engineering is an exciting new cross-disciplinary methodology which applies the principles of engineering and structure-function relationships between normal and pathological tissues to develop biological substitute to restore, maintain or improve tissue function. Tissue engineering...... therefore involves a melange of approaches encompassing developmental biology, tissue mechanics, medicine, cell differentiation and survival biology, mechanostransduction and nano-fabrication technology. The central tissue of interest in this review is cartilage. Traumatic injuries, congenital abnormalities...... engineering approaches and many of these are discussed and their in vitro and in vivo applications covered in this review. Tissue engineering is entering an exciting era; significant advances have been made; however, many technical challenges remain to be solved before this technology becomes widely...

  5. Soft tissue aneurysmal bone cyst

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.L.; Gielen, J.L.; Delrue, F.; De Schepper, A.M.A. [Department of Radiology, Universitair Ziekenhuis Antwerpen (University of Antwerp), Wilrijkstraat 10, 2650, Edegem (Belgium); Salgado, R. [Department of Pathology, Universitair Ziekenhuis Antwerpen (University of Antwerp), Wilrijkstraat 10, 2650, Edegem (Belgium)

    2004-08-01

    A soft tissue aneurysmal bone cyst located in the right gluteus medius of a 21-year-old man is reported. On conventional radiography, the lesion demonstrated a spherically trabeculated mass with a calcific rim. On CT scan, it showed a well-organized peripheral calcification resembling a myositis ossificans. On MRI, it presented as a multilocular, cystic lesion with fluid-fluid levels. The lesion had no solid components except for intralesional septa. Although findings on imaging and histology were identical to those described in classical aneurysmal bone cyst, diagnosis was delayed because of lack of knowledge of this entity and its resemblance to the more familiar post-traumatic heterotopic ossification (myositis ossificans). (orig.)

  6. Industrial tissue: perennialization of suppliers

    International Nuclear Information System (INIS)

    Pin, M.; Hutin, J.P.; Tetreau, F.

    1996-01-01

    The durability of industrial tissue is a necessary condition, and certainly the most important, for the performance of actual park and the successful of its renewal. Reciprocally, the maintenance and the evolution of the actual park, the preparation of its renewal, are sources of activities to insure this durability of industrial and favour their international development. In the period of reduced activity, which began for the nuclear market, the dialogue which has always existed between EDF and its suppliers must be reinforced, in the respect of their respective responsibility, to insure: a right reciprocal understanding of activities and strategies, a right adaptation to these activities, and finally, the maintenance of the competitiveness. (N.C.)

  7. Stem Cells and Tissue Engineering

    CERN Document Server

    Pavlovic, Mirjana

    2013-01-01

    Stem cells are the building blocks for all other cells in an organism. The human body has about 200 different types of cells and any of those cells can be produced by a stem cell. This fact emphasizes the significance of stem cells in transplantational medicine, regenerative therapy and bioengineering. Whether embryonic or adult, these cells can be used for the successful treatment of a wide range of diseases that were not treatable before, such as osteogenesis imperfecta in children, different forms of leukemias, acute myocardial infarction, some neural damages and diseases, etc. Bioengineering, e.g. successful manipulation of these cells with multipotential capacity of differentiation toward appropriate patterns and precise quantity, are the prerequisites for successful outcome and treatment. By combining in vivo and in vitro techniques, it is now possible to manage the wide spectrum of tissue damages and organ diseases. Although the stem-cell therapy is not a response to all the questions, it provides more...

  8. Variation in tissue outcome of ovine and human engineered heart valve constructs: relevance for tissue engineering.

    Science.gov (United States)

    van Geemen, Daphne; Driessen-Mol, Anita; Grootzwagers, Leonie G M; Soekhradj-Soechit, R Sarita; Riem Vis, Paul W; Baaijens, Frank P T; Bouten, Carlijn V C

    2012-01-01

    Clinical application of tissue engineered heart valves requires precise control of the tissue culture process to predict tissue composition and mechanical properties prior to implantation, and to understand the variation in tissue outcome. To this end we investigated cellular phenotype and tissue properties of ovine (n = 8) and human (n = 7) tissue engineered heart valve constructs to quantify variations in tissue outcome within species, study the differences between species and determine possible indicators of tissue outcome. Tissue constructs consisted of polyglycolic acid/poly-4-hydroxybutyrate scaffolds, seeded with myofibroblasts obtained from the jugular vein (sheep) or the saphenous vein (from humans undergoing cardiac surgery) and cultured under static conditions. Prior to seeding, protein expression of α-smooth muscle actin, vimentin, nonmuscle myosin heavy chain and heat shock protein 47 were determined to identify differences at an early stage of the tissue engineering process. After 4 weeks of culture, tissue composition and mechanical properties were quantified as indicators of tissue outcome. After 4 weeks of tissue culture, tissue properties of all ovine constructs were comparable, while there was a larger variation in the properties of the human constructs, especially the elastic modulus and collagen content. In addition, ovine constructs differed in composition from the human constructs. An increased number of α-smooth muscle actin-positive cells before seeding was correlated with the collagen content in the engineered heart valve constructs. Moreover, tissue stiffness increased with increasing collagen content. The results suggest that the culture process of ovine tissues can be controlled, whereas the mechanical properties, and hence functionality, of tissues originating from human material are more difficult to control. On-line evaluation of tissue properties during culture or more early cellular markers to predict the properties of autologous

  9. Ultrasonic Histotripsy for Tissue Therapy

    International Nuclear Information System (INIS)

    Pahk, K J; Saffari, N; Dhar, D K; Malago, M

    2015-01-01

    Hepatocyte transplantation has been considered and investigated as a promising and alternative method to liver transplantation for treating liver-based metabolic disorder in newborns over the past two decades. Although some clinical trials have been conducted and shown clinical benefits and outcomes, it is difficult to deliver and achieve a desired level of integration and transplantation of hepatocytes in the liver parenchyma. To overcome this problem, this work introduces an alternative method to a portal-infused-hepatocyte cell transplantation. To improve the level of engraftment of transplantable hepatocytes, these are injected directly into cavities generated by ultrasonic histotripsy. Histotripsy is an extracorporeal noninvasive technique which has been recently developed using high intensity focused ultrasound (HIFU) for inducing tissue fractionation with no coagulative necrosis. The exact mechanisms for the tissue fractionation are not well understood yet; but the possible mechanisms are thought to be a combination of nonlinear wave propagation effect, explosive bubble growth and ultrasonic atomization. The main objectives of this work are to demonstrate the feasibility of this new cell therapy and evaluate and distinguish between the different types of cavitation activity for either a thermally or a mechanically induced lesion. In the present work, numerical studies on the bubble dynamics (the Gilmore-Akulichev bubble model coupled with the Khokhlov-Zabolotskaya-Kuznetsov equation) and both ex- and in vivo liver experiments are conducted with histological analysis (haematoxylin and eosin stain). The numerical and the experimental results suggest that (a) the acoustic emissions emitted during the thermal ablation and the histotripsy exposure can be distinguished both numerically and experimentally and (b) the proposed cell therapy may potentially form an effective and safe clinical treatment for replacing and correcting disordered hepatocytes, although the

  10. Electromechanical Properties of Bone Tissue.

    Science.gov (United States)

    Regimbal, Raymond L.

    Discrepancies between calculated and empirical properties of bone are thought to be due to a general lack of consideration for the extent and manner(s) with which bone components interact at the molecular level. For a bone component in physiological fluid or whenever two phases are in contact, there is a region between the bulk phases called the electrical double layer which is marked by a separation of electric charges. For the purpose of studying electrical double layer interactions, the method of particle microelectrophoresis was used to characterize bone and its major constituents on the basis of the net charge they bear when suspended in ionic media of physiological relevance. With the data presented as pH versus zeta (zeta ) potential, the figures reveal an isoelectric point (IEP) for bone mineral near pH 8.6, whereas intact and EDTA demineralized bone tissue both exhibit IEPs near pH 5.1. While these data demonstrate the potential for a significant degree of coulombic interaction between the bone mineral and organic constituent double layers, it was also observed that use of inorganic phosphate buffers, as a specific marker for bone mineral, resulted in (1) an immediate reversal, from positive to negative, of the bone mineral zeta potential (2) rendered the zeta potential of intact bone more negative in a manner linearly dependent on both time and temperature and (3) had no affect on demineralized bone (P load for a 3 day period. While it is thus demonstrated that the major inorganic and organic phases of bone are electromechanically coupled, a thermodynamic consideration of the data suggests that the nature of the bond is to preserve mineral and organic phase electroneutralities by participating in electrical double layer interactions. The results are discussed in terms of bone mechanical modeling, electrokinetic properties, aging, tissue-implant compatibility and the etiologies of bone pathologic conditions.

  11. Ultrasonic Histotripsy for Tissue Therapy

    Science.gov (United States)

    Pahk, K. J.; Dhar, D. K.; Malago, M.; Saffari, N.

    2015-01-01

    Hepatocyte transplantation has been considered and investigated as a promising and alternative method to liver transplantation for treating liver-based metabolic disorder in newborns over the past two decades. Although some clinical trials have been conducted and shown clinical benefits and outcomes, it is difficult to deliver and achieve a desired level of integration and transplantation of hepatocytes in the liver parenchyma. To overcome this problem, this work introduces an alternative method to a portal-infused-hepatocyte cell transplantation. To improve the level of engraftment of transplantable hepatocytes, these are injected directly into cavities generated by ultrasonic histotripsy. Histotripsy is an extracorporeal noninvasive technique which has been recently developed using high intensity focused ultrasound (HIFU) for inducing tissue fractionation with no coagulative necrosis. The exact mechanisms for the tissue fractionation are not well understood yet; but the possible mechanisms are thought to be a combination of nonlinear wave propagation effect, explosive bubble growth and ultrasonic atomization. The main objectives of this work are to demonstrate the feasibility of this new cell therapy and evaluate and distinguish between the different types of cavitation activity for either a thermally or a mechanically induced lesion. In the present work, numerical studies on the bubble dynamics (the Gilmore-Akulichev bubble model coupled with the Khokhlov-Zabolotskaya-Kuznetsov equation) and both ex- and in vivo liver experiments are conducted with histological analysis (haematoxylin and eosin stain). The numerical and the experimental results suggest that (a) the acoustic emissions emitted during the thermal ablation and the histotripsy exposure can be distinguished both numerically and experimentally and (b) the proposed cell therapy may potentially form an effective and safe clinical treatment for replacing and correcting disordered hepatocytes, although the

  12. [Tissue engineering of parathyroid gland].

    Science.gov (United States)

    Iovino, F; Armano, G; Auriemma, P P; Sergio, R; De Sena, G; Capuozzo, V; Rosso, F; Marino, G; Papale, F; Grimaldi, A; Barbarisi, A

    2010-01-01

    The postoperative hypoparathyroidism is a not rare complication after total thyroidectomy and/or total parathyroidectomy. Attempts to transplant parathyroid tissue began in 1975 with the work of Wells, but still today results are disappointing. However, with the development of tissue engineering techniques, some experimental approaches to build artificial parathyroid are been made. Bioengineered device, actively secreting PTH, for transplant in patients with iatrogenic hypoparathyroidism is unavailable. Parathyroid cells were obtained from three chronic uremic patients in hemodialysis, operated for secondary hyperparathyroidism. Cell cultures in RPMI medium were subsequently seeded on collagen scaffold (three-dimensional matrix with slow biodegradation). Collagen is the major component of the extracellular matrix and thus is a good substrate for cell adhesion and growth. Culture media, with a low calcium concentration, were optimised to physiologically stimulate parathyroid hormone secretion. Cell cultures were morphologically observed in optical and electron (ESEM) microscopy and metabolically assayed by MTT method until the tenth week. Besides, concentration of parathyroid hormone in the culture medium has been measured for several weeks. After 24 hours of culture in RPMI, cells extracted from human parathyroid glands were nearly all adherent and organised in clusters to resemble the glandular organization. The cellular population consisted predominantly of parathyroid cells (90-95%). On collagen scaffolds, cells maintains an epithelial-like morphology also after 10 weeks, colonizing the scaffold surface and keeping a good proliferative rate with a discrete production of parathyroid hormone. The use of parathyroid cells extracted from patients with secondary hyperparathyroidism was certainly an appropriate choice that enabled us to achieve these results, that albeit partial bode well for the experimental in vivo animal model. The bioengineered scaffolds when

  13. Transcriptome architecture across tissues in the pig

    Directory of Open Access Journals (Sweden)

    Folch Josep M

    2008-04-01

    Full Text Available Abstract Background Artificial selection has resulted in animal breeds with extreme phenotypes. As an organism is made up of many different tissues and organs, each with its own genetic programme, it is pertinent to ask: How relevant is tissue in terms of total transcriptome variability? Which are the genes most distinctly expressed between tissues? Does breed or sex equally affect the transcriptome across tissues? Results In order to gain insight on these issues, we conducted microarray expression profiling of 16 different tissues from four animals of two extreme pig breeds, Large White and Iberian, two males and two females. Mixed model analysis and neighbor – joining trees showed that tissues with similar developmental origin clustered closer than those with different embryonic origins. Often a sound biological interpretation was possible for overrepresented gene ontology categories within differentially expressed genes between groups of tissues. For instance, an excess of nervous system or muscle development genes were found among tissues of ectoderm or mesoderm origins, respectively. Tissue accounted for ~11 times more variability than sex or breed. Nevertheless, we were able to confidently identify genes with differential expression across tissues between breeds (33 genes and between sexes (19 genes. The genes primarily affected by sex were overall different than those affected by breed or tissue. Interaction with tissue can be important for differentially expressed genes between breeds but not so much for genes whose expression differ between sexes. Conclusion Embryonic development leaves an enduring footprint on the transcriptome. The interaction in gene × tissue for differentially expressed genes between breeds suggests that animal breeding has targeted differentially each tissue's transcriptome.

  14. A Novel Albumin-Based Tissue Scaffold for Autogenic Tissue Engineering Applications

    OpenAIRE

    Li, Pei-Shan; -Liang Lee, I.; Yu, Wei-Lin; Sun, Jui-Sheng; Jane, Wann-Neng; Shen, Hsin-Hsin

    2014-01-01

    Tissue scaffolds provide a framework for living tissue regeneration. However, traditional tissue scaffolds are exogenous, composed of metals, ceramics, polymers, and animal tissues, and have a defined biocompatibility and application. This study presents a new method for obtaining a tissue scaffold from blood albumin, the major protein in mammalian blood. Human, bovine, and porcine albumin was polymerised into albumin polymers by microbial transglutaminase and was then cast by freeze-drying-b...

  15. Modeling Tissue Growth Within Nonwoven Scaffolds Pores

    Science.gov (United States)

    Church, Jeffrey S.; Alexander, David L.J.; Russell, Stephen J.; Ingham, Eileen; Ramshaw, John A.M.; Werkmeister, Jerome A.

    2011-01-01

    In this study we present a novel approach for predicting tissue growth within the pores of fibrous tissue engineering scaffolds. Thin nonwoven polyethylene terephthalate scaffolds were prepared to characterize tissue growth within scaffold pores, by mouse NR6 fibroblast cells. On the basis of measurements of tissue lengths at fiber crossovers and along fiber segments, mathematical models were determined during the proliferative phase of cell growth. Tissue growth at fiber crossovers decreased with increasing interfiber angle, with exponential relationships determined on day 6 and 10 of culture. Analysis of tissue growth along fiber segments determined two growth profiles, one with enhanced growth as a result of increased tissue lengths near the fiber crossover, achieved in the latter stage of culture. Derived mathematical models were used in the development of a software program to visualize predicted tissue growth within a pore. This study identifies key pore parameters that contribute toward tissue growth, and suggests models for predicting this growth, based on fibroblast cells. Such models may be used in aiding scaffold design, for optimum pore infiltration during the tissue engineering process. PMID:20687775

  16. Multiscale mechanical modeling of soft biological tissues

    Science.gov (United States)

    Stylianopoulos, Triantafyllos

    2008-10-01

    Soft biological tissues include both native and artificial tissues. In the human body, tissues like the articular cartilage, arterial wall, and heart valve leaflets are examples of structures composed of an underlying network of collagen fibers, cells, proteins and molecules. Artificial tissues are less complex than native tissues and mainly consist of a fiber polymer network with the intent of replacing lost or damaged tissue. Understanding of the mechanical function of these materials is essential for many clinical treatments (e.g. arterial clamping, angioplasty), diseases (e.g. arteriosclerosis) and tissue engineering applications (e.g. engineered blood vessels or heart valves). This thesis presents the derivation and application of a multiscale methodology to describe the macroscopic mechanical function of soft biological tissues incorporating directly their structural architecture. The model, which is based on volume averaging theory, accounts for structural parameters such as the network volume fraction and orientation, the realignment of the fibers in response to strain, the interactions among the fibers and the interactions between the fibers and the interstitial fluid in order to predict the overall tissue behavior. Therefore, instead of using a constitutive equation to relate strain to stress, the tissue microstructure is modeled within a representative volume element (RVE) and the macroscopic response at any point in the tissue is determined by solving a micromechanics problem in the RVE. The model was applied successfully to acellular collagen gels, native blood vessels, and electrospun polyurethane scaffolds and provided accurate predictions for permeability calculations in isotropic and oriented fiber networks. The agreement of model predictions with experimentally determined mechanical properties provided insights into the mechanics of tissues and tissue constructs, while discrepancies revealed limitations of the model framework.

  17. Engineering complex orthopaedic tissues via strategic biomimicry.

    Science.gov (United States)

    Qu, Dovina; Mosher, Christopher Z; Boushell, Margaret K; Lu, Helen H

    2015-03-01

    The primary current challenge in regenerative engineering resides in the simultaneous formation of more than one type of tissue, as well as their functional assembly into complex tissues or organ systems. Tissue-tissue synchrony is especially important in the musculoskeletal system, wherein overall organ function is enabled by the seamless integration of bone with soft tissues such as ligament, tendon, or cartilage, as well as the integration of muscle with tendon. Therefore, in lieu of a traditional single-tissue system (e.g., bone, ligament), composite tissue scaffold designs for the regeneration of functional connective tissue units (e.g., bone-ligament-bone) are being actively investigated. Closely related is the effort to re-establish tissue-tissue interfaces, which is essential for joining these tissue building blocks and facilitating host integration. Much of the research at the forefront of the field has centered on bioinspired stratified or gradient scaffold designs which aim to recapitulate the structural and compositional inhomogeneity inherent across distinct tissue regions. As such, given the complexity of these musculoskeletal tissue units, the key question is how to identify the most relevant parameters for recapitulating the native structure-function relationships in the scaffold design. Therefore, the focus of this review, in addition to presenting the state-of-the-art in complex scaffold design, is to explore how strategic biomimicry can be applied in engineering tissue connectivity. The objective of strategic biomimicry is to avoid over-engineering by establishing what needs to be learned from nature and defining the essential matrix characteristics that must be reproduced in scaffold design. Application of this engineering strategy for the regeneration of the most common musculoskeletal tissue units (e.g., bone-ligament-bone, muscle-tendon-bone, cartilage-bone) will be discussed in this review. It is anticipated that these exciting efforts will

  18. Engineering Complex Orthopaedic Tissues via Strategic Biomimicry

    Science.gov (United States)

    Qu, Dovina; Mosher, Christopher Z.; Boushell, Margaret K.; Lu, Helen H.

    2014-01-01

    The primary current challenge in regenerative engineering resides in the simultaneous formation of more than one type of tissue, as well as their functional assembly into complex tissues or organ systems. Tissue-tissue synchrony is especially important in the musculoskeletal system, whereby overall organ function is enabled by the seamless integration of bone with soft tissues such as ligament, tendon, or cartilage, as well as the integration of muscle with tendon. Therefore, in lieu of a traditional single-tissue system (e.g. bone, ligament), composite tissue scaffold designs for the regeneration of functional connective tissue units (e.g. bone-ligament-bone) are being actively investigated. Closely related is the effort to re-establish tissue-tissue interfaces, which is essential for joining these tissue building blocks and facilitating host integration. Much of the research at the forefront of the field has centered on bioinspired stratified or gradient scaffold designs which aim to recapitulate the structural and compositional inhomogeneity inherent across distinct tissue regions. As such, given the complexity of these musculoskeletal tissue units, the key question is how to identify the most relevant parameters for recapitulating the native structure-function relationships in the scaffold design. Therefore, the focus of this review, in addition to presenting the state-of-the-art in complex scaffold design, is to explore how strategic biomimicry can be applied in engineering tissue connectivity. The objective of strategic biomimicry is to avoid over-engineering by establishing what needs to be learned from nature and defining the essential matrix characteristics that must be reproduced in scaffold design. Application of this engineering strategy for the regeneration of the most common musculoskeletal tissue units (e.g. bone-ligament-bone, muscle-tendon-bone, cartilage-bone) will be discussed in this review. It is anticipated that these exciting efforts will

  19. Imaging of musculoskeletal soft tissue infections

    International Nuclear Information System (INIS)

    Turecki, Marcin B.; Taljanovic, Mihra S.; Holden, Dean A.; Hunter, Tim B.; Rogers, Lee F.; Stubbs, Alana Y.; Graham, Anna R.

    2010-01-01

    Prompt and appropriate imaging work-up of the various musculoskeletal soft tissue infections aids early diagnosis and treatment and decreases the risk of complications resulting from misdiagnosis or delayed diagnosis. The signs and symptoms of musculoskeletal soft tissue infections can be nonspecific, making it clinically difficult to distinguish between disease processes and the extent of disease. Magnetic resonance imaging (MRI) is the imaging modality of choice in the evaluation of soft tissue infections. Computed tomography (CT), ultrasound, radiography and nuclear medicine studies are considered ancillary. This manuscript illustrates representative images of superficial and deep soft tissue infections such as infectious cellulitis, superficial and deep fasciitis, including the necrotizing fasciitis, pyomyositis/soft tissue abscess, septic bursitis and tenosynovitis on different imaging modalities, with emphasis on MRI. Typical histopathologic findings of soft tissue infections are also presented. The imaging approach described in the manuscript is based on relevant literature and authors' personal experience and everyday practice. (orig.)

  20. Tissue refractometry using Hilbert phase microscopy.

    Science.gov (United States)

    Lue, Niyom; Bewersdorf, Joerg; Lessard, Mark D; Badizadegan, Kamran; Dasari, Ramachandra R; Feld, Michael S; Popescu, Gabriel

    2007-12-15

    We present, for the first time to our knowledge, quantitative phase images associated with unstained 5 mum thick tissue slices of mouse brain, spleen, and liver. The refractive properties of the tissue are retrieved in terms of the average refractive index and its spatial variation. We find that the average refractive index varies significantly with tissue type, such that the brain is characterized by the lowest value and the liver by the highest. The spatial power spectra of the phase images reveal power law behavior with different exponents for each tissue type. This approach opens a new possibility for stain-free characterization of tissues, where the diagnostic power is provided by the intrinsic refractive properties of the biological structure. We present results obtained for liver tissue affected by a lysosomal storage disease and show that our technique can quantify structural changes during this disease development.

  1. Tissue engineering scheming by artificial intelligence.

    Science.gov (United States)

    Xu, J; Ge, H; Zhou, X; Yang, D

    2005-01-01

    Tissue engineers are often confused when seeking the most effective, economical and secure scheme for tissue engineering. The aim of this study is to generate tissue engineering schemes with artificial intelligence instead of human intelligence. The experimental data of tissue engineered cartilage were integrated and standardized with a centralized database, and a scheme engine was developed using artificial intelligent methods (artificial neural networks and decision trees). The scheme engine was trained with existing cases in the database, and then was used to generate tissue engineering schemes for new experimental animals. Following the schemes generated by the artificial intelligent system, we cured 18 of the 20 experimental animals. In conclusion, artificial intelligence is a powerful method for decision making in the tissue engineering realm.

  2. Adipose and mammary epithelial tissue engineering.

    Science.gov (United States)

    Zhu, Wenting; Nelson, Celeste M

    2013-01-01

    Breast reconstruction is a type of surgery for women who have had a mastectomy, and involves using autologous tissue or prosthetic material to construct a natural-looking breast. Adipose tissue is the major contributor to the volume of the breast, whereas epithelial cells comprise the functional unit of the mammary gland. Adipose-derived stem cells (ASCs) can differentiate into both adipocytes and epithelial cells and can be acquired from autologous sources. ASCs are therefore an attractive candidate for clinical applications to repair or regenerate the breast. Here we review the current state of adipose tissue engineering methods, including the biomaterials used for adipose tissue engineering and the application of these techniques for mammary epithelial tissue engineering. Adipose tissue engineering combined with microfabrication approaches to engineer the epithelium represents a promising avenue to replicate the native structure of the breast.

  3. Imaging of musculoskeletal soft tissue infections

    Energy Technology Data Exchange (ETDEWEB)

    Turecki, Marcin B.; Taljanovic, Mihra S.; Holden, Dean A.; Hunter, Tim B.; Rogers, Lee F. [University of Arizona HSC, Department of Radiology, Tucson, AZ (United States); Stubbs, Alana Y. [Southern Arizona VA Health Care System, Department of Radiology, Tucson, AZ (United States); Graham, Anna R. [University of Arizona HSC, Department of Pathology, Tucson, AZ (United States)

    2010-10-15

    Prompt and appropriate imaging work-up of the various musculoskeletal soft tissue infections aids early diagnosis and treatment and decreases the risk of complications resulting from misdiagnosis or delayed diagnosis. The signs and symptoms of musculoskeletal soft tissue infections can be nonspecific, making it clinically difficult to distinguish between disease processes and the extent of disease. Magnetic resonance imaging (MRI) is the imaging modality of choice in the evaluation of soft tissue infections. Computed tomography (CT), ultrasound, radiography and nuclear medicine studies are considered ancillary. This manuscript illustrates representative images of superficial and deep soft tissue infections such as infectious cellulitis, superficial and deep fasciitis, including the necrotizing fasciitis, pyomyositis/soft tissue abscess, septic bursitis and tenosynovitis on different imaging modalities, with emphasis on MRI. Typical histopathologic findings of soft tissue infections are also presented. The imaging approach described in the manuscript is based on relevant literature and authors' personal experience and everyday practice. (orig.)

  4. Transmission dose estimation algorithm for tissue deficit

    International Nuclear Information System (INIS)

    Yun, Hyong Geun; Shin, Kyo Chul; Chie, Eui Kyu; Huh, Soon Nyung; Woo, Hong Gyun; Ha, Sung Whan; Lee, Hyoung Koo

    2002-01-01

    Measurement of transmission dose is useful for in vivo dosimetry. In this study, previous algorithm for estimation of transmission dose was modified for use in cases with tissue deficit. The beam data was measured with flat solid phantom in various conditions of tissue deficit. New algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. The algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients using multiple sheets of solid phantoms. The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within ± 1.0% in most situations and within ± 3.0% in experimental settings with irregular contours mimicking breast cancer treatment set-up. Developed algorithm could accurately reflect the effect of tissue deficit and irregularly shaped body contour on transmission dosimetry

  5. Dopaminergic Immunofluorescence Studies in Kidney Tissue.

    Science.gov (United States)

    Gildea, J J; Van Sciver, R E; McGrath, H E; Kemp, B A; Jose, P A; Carey, R M; Felder, R A

    2017-01-01

    The kidney is a highly integrated system of specialized differentiated cells that are responsible for fluid and electrolyte balance in the body. While much of today's research focuses on isolated nephron segments or cells from nephron segments grown in tissue culture, an often overlooked technique that can provide a unique view of many cell types in the kidney is slice culture. Here, we describe techniques that use freshly excised kidney tissue from rats to perform a variety of experiments shortly after isolating the tissue. By slicing the rat kidney in a "bread loaf" format, multiple studies can be performed on slices from the same tissue in parallel. Cryosectioning and staining of the tissue allow for the evaluation of physiological or biochemical responses in a wide variety of specific nephron segments. The procedures described within this chapter can also be extended to human or mouse kidney tissue.

  6. Tissue Factor Structure and Function

    Directory of Open Access Journals (Sweden)

    Saulius Butenas

    2012-01-01

    Full Text Available Tissue factor (TF is an integral membrane protein that is essential to life. It is a component of the factor VIIa-TF complex enzyme and plays a primary role in both normal hemostasis and thrombosis. With a vascular injury, TF becomes exposed to blood and binds plasma factor VIIa, and the resulting complex initiates a series of enzymatic reactions leading to clot formation and vascular sealing. Many cells, both healthy, and tumor cells, produce detectable amounts of TF, especially when they are stimulated by various agents. Despite the relative simplicity and small size of TF, there are numerous contradictory reports about the synthesis and presentation of TF on blood cells and circulation in normal blood either on microparticles or as a soluble protein. Another subject of controversy is related to the structure/function of TF. It has been almost commonly accepted that cell-surface-associated TF has low (if any activity, that is, is “encrypted” and requires specific conditions/reagents to become active, that is, “decrypted.” However there is a lack of agreement related to the mechanism and processes leading to alterations in TF function. In this paper TF structure, presentation, and function, and controversies concerning these features are discussed.

  7. Terahertz sensing in corneal tissues

    Science.gov (United States)

    Bennett, David B.; Taylor, Zachary D.; Tewari, Pria; Singh, Rahul S.; Culjat, Martin O.; Grundfest, Warren S.; Sassoon, Daniel J.; Johnson, R. Duncan; Hubschman, Jean-Pierre; Brown, Elliott R.

    2011-01-01

    This work introduces the potential application of terahertz (THz) sensing to the field of ophthalmology, where it is uniquely suited due to its nonionizing photon energy and high sensitivity to water content. Reflective THz imaging and spectrometry data are reported on ex-vivo porcine corneas prepared with uniform water concentrations using polyethylene glycol (PEG) solutions. At 79% water concentration by mass, the measured reflectivity of the cornea was 20.4%, 14.7%, 11.7%, 9.6%, and 7.4% at 0.2, 0.4, 0.6, 0.8, and 1 THz, respectively. Comparison of nine corneas hydrated from 79.1% to 91.5% concentration by mass demonstrated an approximately linear relationship between THz reflectivity and water concentration, with a monotonically decreasing slope as the frequency increases. The THz-corneal tissue interaction is simulated with a Bruggeman model with excellent agreement. THz applications to corneal dystrophy, graft rejection, and refractive surgery are examined from the context of these measurements. PMID:21639581

  8. Keratoconus: Tissue Engineering and Biomaterials

    Directory of Open Access Journals (Sweden)

    Dimitrios Karamichos

    2014-09-01

    Full Text Available Keratoconus (KC is a bilateral, asymmetric, corneal disorder that is characterized by progressive thinning, steepening, and potential scarring. The prevalence of KC is stated to be 1 in 2000 persons worldwide; however, numbers vary depending on size of the study and regions. KC appears more often in South Asian, Eastern Mediterranean, and North African populations. The cause remains unknown, although a variety of factors have been considered. Genetics, cellular, and mechanical changes have all been reported; however, most of these studies have proven inconclusive. Clearly, the major problem here, like with any other ocular disease, is quality of life and the threat of vision loss. While most KC cases progress until the third or fourth decade, it varies between individuals. Patients may experience periods of several months with significant changes followed by months or years of no change, followed by another period of rapid changes. Despite the major advancements, it is still uncertain how to treat KC at early stages and prevent vision impairment. There are currently limited tissue engineering techniques and/or “smart” biomaterials that can help arrest the progression of KC. This review will focus on current treatments and how biomaterials may hold promise for the future.

  9. Tissue-engineered heart valves.

    Science.gov (United States)

    Filová, E; Straka, F; Mirejovský, T; Masín, J; Bacáková, L

    2009-01-01

    Currently-used mechanical and biological heart valve prostheses have several disadvantages. Mechanical prostheses, based on carbon, metallic and polymeric components, require permanent anticoagulation treatment, and their usage often leads to adverse reactions, e.g. thromboembolic complications and endocarditis. Xenogenous and allogenous biological prostheses are associated with immune reaction, thrombosis and degeneration, and thus they have a high rate of reoperation. Biological prostheses of autologous origin, such as pulmonary autografts, often burden the patient with a complicated surgery and the risk of reoperation. Therefore, efforts are being made to prepare bioartificial heart valves with an autologous biological component by methods of tissue engineering. They should be biocompatible, durable, endowed with appropriate mechanical properties and able to grow with a child. For this purpose, scaffolds composed of synthetic materials, such as poly(lactic acid), poly(caprolactone), poly(4-hydroxybutyrate), hydrogels or natural polymers, e.g. collagen, elastin, fibrin or hyaluronic acid, have been seeded with autologous differentiated, progenitor or stem cells. Promising results have been obtained with nanostructured scaffolds, and also with cultivation in special dynamic bioreactors prior to implantation of the bioartificial grafts into an animal organism.

  10. Cell sheet-based tissue engineering for fabricating 3-dimensional heart tissues.

    Science.gov (United States)

    Shimizu, Tatsuya

    2014-01-01

    In addition to stem cell biology, tissue engineering is an essential research field for regenerative medicine. In contrast to cell injection, bioengineered tissue transplantation minimizes cell loss and has the potential to repair tissue defects. A popular approach is scaffold-based tissue engineering, which utilizes a biodegradable polymer scaffold for seeding cells; however, new techniques of cell sheet-based tissue engineering have been developed. Cell sheets are harvested from temperature-responsive culture dishes by simply lowering the temperature. Monolayer or stacked cell sheets are transplantable directly onto damaged tissues and cell sheet transplantation has already been clinically applied. Cardiac cell sheet stacking produces pulsatile heart tissue; however, lack of vasculature limits the viable tissue thickness to 3 layers. Multistep transplantation of triple-layer cardiac cell sheets cocultured with endothelial cells has been used to form thick vascularized cardiac tissue in vivo. Furthermore, in vitro functional blood vessel formation within 3-dimensional (3D) tissues has been realized by successfully imitating in vivo conditions. Triple-layer cardiac cell sheets containing endothelial cells were layered on vascular beds and the constructs were media-perfused using novel bioreactor systems. Interestingly, cocultured endothelial cells migrate into the vascular beds and form perfusable blood vessels. An in vitro multistep procedure has also enabled the fabrication of thick, vascularized heart tissues. Cell sheet-based tissue engineering has revealed great potential to fabricate 3D cardiac tissues and should contribute to future treatment of severe heart diseases and human tissue model production.

  11. Tissue Engineering in Regenerative Dental Therapy

    OpenAIRE

    Hiral Jhaveri-Desai; Shaleen Khetarpal

    2011-01-01

    Tissue engineering is amongst the latest exciting technologies having impacted the field of dentistry. Initially considered as a futuristic approach, tissue engineering is now being successfully applied in regenerative surgery. This article reviews the important determinants of tissue engineering and how they contribute to the improvement of wound healing and surgical outcomes in the oral region. Furthermore, we shall address the clinical applications of engineering involving oral and maxillo...

  12. [Diagnosis of calcified deposits in soft tissues].

    Science.gov (United States)

    Wybier, M; Laredo, J D; Parlier, C; Champsaur, P

    1997-01-01

    Calcific deposit within soft tissues is frequently a clue for diagnosis. The radiological analysis of a calcific deposit within soft tissues includes the following aspects: the basic structure of the calcification, the grade of differentiation of the calcification, the site of the calcification, the number of calcific deposits, the shape of the calcification, the changes in the adjacent non-calcified soft tissues and in the adjacent bone, the course of the clinical signs, the course of the radiological abnormalities.

  13. Single domain antibodies in tissue engineering

    OpenAIRE

    Rodrigues, E.D.

    2014-01-01

    The aim of this thesis is to demonstrate the potential of VHH in tissue engineering applications, with a focus on bone and cartilage tissue regeneration. After a general introduction to this thesis in chapter 1, the selection of VHH targeting growth factors is described in chapter 2. VHH were selected to target growth factors relevant in skeletal tissue engineering and VHH were found to modulate BMP activity with high affinity. Chapter 3 describes the immobilization of VHH and its potential t...

  14. Soft tissue and esthetic considerations around implants

    OpenAIRE

    Joann Pauline George; Sangeeta Dhir

    2015-01-01

    The health of the peri – implant tissues play an important in the long term outcome of dental implants. The absence of keratinized gingiva (KG) may be a risk factor for developing recession or peri –implantitis. However there is still ambiguity in the need for keratinized gingiva around dental implants. The preservation and reconstruction of soft tissue around dental implants is an integral component of dental Implantology. There is no long-term evidence whether augmented soft tissues can be ...

  15. Soft tissue grafting to improve implant esthetics

    Directory of Open Access Journals (Sweden)

    Moawia M Kassab

    2010-09-01

    Full Text Available Moawia M KassabDivision of Periodontics, Marquette University, School of Dentistry, Milwaukee, WI, USAAbstract: Dental implants are becoming the treatment of choice to replace missing teeth, especially if the adjacent teeth are free of restorations. When minimal bone width is present, implant placement becomes a challenge and often resulting in recession and dehiscence around the implant that leads to subsequent gingival recession. To correct such defect, the author turned to soft tissue autografting and allografting to correct a buccal dehiscence around tooth #24 after a malpositioned implant placed by a different surgeon. A 25-year-old woman presented with the chief complaint of gingival recession and exposure of implant threads around tooth #24. The patient received three soft tissue grafting procedures to augment the gingival tissue. The first surgery included a connective tissue graft to increase the width of the keratinized gingival tissue. The second surgery included the use of autografting (connective tissue graft to coronally position the soft tissue and achieve implant coverage. The third and final surgery included the use of allografting material Alloderm to increase and mask the implant from showing through the gingiva. Healing period was uneventful for the patient. After three surgical procedures, it appears that soft tissue grafting has increased the width and height of the gingiva surrounding the implant. The accomplished thickness of gingival tissue appeared to mask the showing of implant threads through the gingival tissue and allowed for achieving the desired esthetic that the patient desired. The aim of the study is to present a clinical case with soft tissue grafting procedures.Keywords: case report, connective tissue, dental implants, allograft, coronally positioned flap

  16. Medical image of the week: granulation tissue

    Directory of Open Access Journals (Sweden)

    Ganesh A

    2014-03-01

    Full Text Available A 57 year old woman presented with a tickling sensation in the back of throat and intermittent bleeding from the healing stoma one month after decannulation of her tracheostomy tube. On bronchoscopy a granuloma with surrounding granulation tissue was present in the subglottic space (Figure 1. Argon plasma coagulation (APC was performed to cauterize the granulation tissue (Figure 2. Formation of granulation tissue after tracheostomy is a common complication which can result in tracheal stenosis. APC and electrocautery using flexible bronchoscopy has been shown to safely and effectively remove the granulation tissue.

  17. Principles, Techniques, and Applications of Tissue Microfluidics

    Science.gov (United States)

    Wade, Lawrence A.; Kartalov, Emil P.; Shibata, Darryl; Taylor, Clive

    2011-01-01

    The principle of tissue microfluidics and its resultant techniques has been applied to cell analysis. Building microfluidics to suit a particular tissue sample would allow the rapid, reliable, inexpensive, highly parallelized, selective extraction of chosen regions of tissue for purposes of further biochemical analysis. Furthermore, the applicability of the techniques ranges beyond the described pathology application. For example, they would also allow the posing and successful answering of new sets of questions in many areas of fundamental research. The proposed integration of microfluidic techniques and tissue slice samples is called "tissue microfluidics" because it molds the microfluidic architectures in accordance with each particular structure of each specific tissue sample. Thus, microfluidics can be built around the tissues, following the tissue structure, or alternatively, the microfluidics can be adapted to the specific geometry of particular tissues. By contrast, the traditional approach is that microfluidic devices are structured in accordance with engineering considerations, while the biological components in applied devices are forced to comply with these engineering presets.

  18. Segmentation and Quantitative Analysis of Epithelial Tissues.

    Science.gov (United States)

    Aigouy, Benoit; Umetsu, Daiki; Eaton, Suzanne

    2016-01-01

    Epithelia are tissues that regulate exchanges with the environment. They are very dynamic and can acquire virtually any shape; at the cellular level, they are composed of cells tightly connected by junctions. Most often epithelia are amenable to live imaging; however, the large number of cells composing an epithelium and the absence of informatics tools dedicated to epithelial analysis largely prevented tissue scale studies. Here we present Tissue Analyzer, a free tool that can be used to segment and analyze epithelial cells and monitor tissue dynamics.

  19. Scalable robotic biofabrication of tissue spheroids

    Energy Technology Data Exchange (ETDEWEB)

    Mehesz, A Nagy; Hajdu, Z; Visconti, R P; Markwald, R R; Mironov, V [Advanced Tissue Biofabrication Center, Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC (United States); Brown, J [Department of Mechanical Engineering, Clemson University, Clemson, SC (United States); Beaver, W [York Technical College, Rock Hill, SC (United States); Da Silva, J V L, E-mail: mironovv@musc.edu [Renato Archer Information Technology Center-CTI, Campinas (Brazil)

    2011-06-15

    Development of methods for scalable biofabrication of uniformly sized tissue spheroids is essential for tissue spheroid-based bioprinting of large size tissue and organ constructs. The most recent scalable technique for tissue spheroid fabrication employs a micromolded recessed template prepared in a non-adhesive hydrogel, wherein the cells loaded into the template self-assemble into tissue spheroids due to gravitational force. In this study, we present an improved version of this technique. A new mold was designed to enable generation of 61 microrecessions in each well of a 96-well plate. The microrecessions were seeded with cells using an EpMotion 5070 automated pipetting machine. After 48 h of incubation, tissue spheroids formed at the bottom of each microrecession. To assess the quality of constructs generated using this technology, 600 tissue spheroids made by this method were compared with 600 spheroids generated by the conventional hanging drop method. These analyses showed that tissue spheroids fabricated by the micromolded method are more uniform in diameter. Thus, use of micromolded recessions in a non-adhesive hydrogel, combined with automated cell seeding, is a reliable method for scalable robotic fabrication of uniform-sized tissue spheroids.

  20. Tissue polarimetry: concepts, challenges, applications, and outlook.

    Science.gov (United States)

    Ghosh, Nirmalya; Vitkin, I Alex

    2011-11-01

    Polarimetry has a long and successful history in various forms of clear media. Driven by their biomedical potential, the use of the polarimetric approaches for biological tissue assessment has also recently received considerable attention. Specifically, polarization can be used as an effective tool to discriminate against multiply scattered light (acting as a gating mechanism) in order to enhance contrast and to improve tissue imaging resolution. Moreover, the intrinsic tissue polarimetry characteristics contain a wealth of morphological and functional information of potential biomedical importance. However, in a complex random medium-like tissue, numerous complexities due to multiple scattering and simultaneous occurrences of many scattering and polarization events present formidable challenges both in terms of accurate measurements and in terms of analysis of the tissue polarimetry signal. In order to realize the potential of the polarimetric approaches for tissue imaging and characterization/diagnosis, a number of researchers are thus pursuing innovative solutions to these challenges. In this review paper, we summarize these and other issues pertinent to the polarized light methodologies in tissues. Specifically, we discuss polarized light basics, Stokes-Muller formalism, methods of polarization measurements, polarized light modeling in turbid media, applications to tissue imaging, inverse analysis for polarimetric results quantification, applications to quantitative tissue assessment, etc.

  1. Analysis of tooth tissues using Raman spectroscopy

    International Nuclear Information System (INIS)

    Timchenko, E.V.; Timchenko, P.E.; Kulabukhova, A.Yu.; Volova, L.T.; Rosenbaum, A.Yu.

    2016-01-01

    The results of experimental studies of healthy tooth tissue and tooth tissues during caries disease are presented. Features of Raman spectrum of tooth tissues during caries disease are obtained: the main changes are detected at wavenumbers 956 cm -1 .1069 cm -1 . corresponding to phosphates. and 1241 cm -1 . 1660 cm -1 . corresponding to collagen III and collagen I. respectively. Were introduced criteria allowing to detect caries and to identify weakening of tooth tissues. preceding the caries. The reliability of research results is confirmed by scanning electron microscopy. (paper)

  2. Mechanical homeostasis regulating adipose tissue volume

    Directory of Open Access Journals (Sweden)

    Svedman Paul

    2007-09-01

    Full Text Available Abstract Background The total body adipose tissue volume is regulated by hormonal, nutritional, paracrine, neuronal and genetic control signals, as well as components of cell-cell or cell-matrix interactions. There are no known locally acting homeostatic mechanisms by which growing adipose tissue might adapt its volume. Presentation of the hypothesis Mechanosensitivity has been demonstrated by mesenchymal cells in tissue culture. Adipocyte differentiation has been shown to be inhibited by stretching in vitro, and a pathway for the response has been elucidated. In humans, intermittent stretching of skin for reconstructional purposes leads to thinning of adipose tissue and thickening of epidermis – findings matching those observed in vitro in response to mechanical stimuli. Furthermore, protracted suspension of one leg increases the intermuscular adipose tissue volume of the limb. These findings may indicate a local homeostatic adipose tissue volume-regulating mechanism based on movement-induced reduction of adipocyte differentiation. This function might, during evolution, have been of importance in confined spaces, where overgrowth of adipose tissue could lead to functional disturbance, as for instance in the turtle. In humans, adipose tissue near muscle might in particular be affected, for instance intermuscularly, extraperitoneally and epicardially. Mechanical homeostasis might also contribute to protracted maintainment of soft tissue shape in the face and neck region. Testing of the hypothesis Assessment of messenger RNA-expression of human adipocytes following activity in adjacent muscle is planned, and study of biochemical and volumetric adipose tissue changes in man are proposed. Implications of the hypothesis The interpretation of metabolic disturbances by means of adipose tissue might be influenced. Possible applications in the head and neck were discussed.

  3. Effects of tissue mechanical properties on susceptibility to histotripsy-induced tissue damage

    Science.gov (United States)

    Vlaisavljevich, Eli; Kim, Yohan; Owens, Gabe; Roberts, William; Cain, Charles; Xu, Zhen

    2014-01-01

    Histotripsy is a non-invasive tissue ablation method capable of fractionating tissue by controlling acoustic cavitation. To determine the fractionation susceptibility of various tissues, we investigated histotripsy-induced damage on tissue phantoms and ex vivo tissues with different mechanical strengths. A histotripsy bubble cloud was formed at tissue phantom surfaces using 5-cycle long ultrasound pulses with peak negative pressure of 18 MPa and PRFs of 10, 100, and 1000 Hz. Results showed significantly smaller lesions were generated in tissue phantoms of higher mechanical strength. Histotripsy was also applied to 43 different ex vivo porcine tissues with a wide range of mechanical properties. Gross morphology demonstrated stronger tissues with higher ultimate stress, higher density, and lower water content were more resistant to histotripsy damage in comparison to weaker tissues. Based on these results, a self-limiting vessel-sparing treatment strategy was developed in an attempt to preserve major vessels while fractionating the surrounding target tissue. This strategy was tested in porcine liver in vivo. After treatment, major hepatic blood vessels and bile ducts remained intact within a completely fractionated liver volume. These results identify varying susceptibilities of tissues to histotripsy therapy and provide a rational basis to optimize histotripsy parameters for treatment of specific tissues.

  4. Cell Sheet-Based Tissue Engineering for Organizing Anisotropic Tissue Constructs Produced Using Microfabricated Thermoresponsive Substrates.

    Science.gov (United States)

    Takahashi, Hironobu; Okano, Teruo

    2015-11-18

    In some native tissues, appropriate microstructures, including orientation of the cell/extracellular matrix, provide specific mechanical and biological functions. For example, skeletal muscle is made of oriented myofibers that is responsible for the mechanical function. Native artery and myocardial tissues are organized three-dimensionally by stacking sheet-like tissues of aligned cells. Therefore, to construct any kind of complex tissue, the microstructures of cells such as myotubes, smooth muscle cells, and cardiomyocytes also need to be organized three-dimensionally just as in the native tissues of the body. Cell sheet-based tissue engineering allows the production of scaffold-free engineered tissues through a layer-by-layer construction technique. Recently, using microfabricated thermoresponsive substrates, aligned cells are being harvested as single continuous cell sheets. The cell sheets act as anisotropic tissue units to build three-dimensional tissue constructs with the appropriate anisotropy. This cell sheet-based technology is straightforward and has the potential to engineer a wide variety of complex tissues. In addition, due to the scaffold-free cell-dense environment, the physical and biological cell-cell interactions of these cell sheet constructs exhibit unique cell behaviors. These advantages will provide important clues to enable the production of well-organized tissues that closely mimic the structure and function of native tissues, required for the future of tissue engineering. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Low oxygen concentrations impair tissue development in tissue-engineered cardiovascular constructs

    NARCIS (Netherlands)

    Vlimmeren, M.A.A. van; Driessen-Mol, A.; Oomens, C.W.J.; Broek, M. van den; Stoop, R.; Bouten, C.V.C.; Baaijens, F.P.T.

    2012-01-01

    Cardiovascular tissue engineering has shown considerable progress, but in vitro tissue conditioning to stimulate the development of a functional extracellular matrix still needs improvement. We investigated the environmental factor oxygen concentration for its potential to increase the amount of

  6. 2010 Great Lakes Human Health Fish Tissue Study Fish Tissue Data Dictionary

    Science.gov (United States)

    The Office of Science and Technology (OST) is providing the fish tissue results from the 2010 Great Lakes Human Health Fish Tissue Study (GLHHFTS). This document includes the “data dictionary” for Mercury, PFC, PBDE and PCBs.

  7. Intermittent straining accelerates the development of tissue properties in engineered heart valve tissue

    NARCIS (Netherlands)

    Rubbens, M.P.; Mol, A.; Boerboom, R.A.; Bank, R.A.; Baaijens, F.P.T.; Bouten, C.V.C.

    2009-01-01

    Tissue-engineered heart valves lack sufficient amounts of functionally organized structures and consequently do not meet in vivo mechanical demands. To optimize tissue architecture and hence improve mechanical properties, various in vitro mechanical conditioning protocols have been proposed, of

  8. Lung tissue mechanics as an emergent phenomenon.

    Science.gov (United States)

    Suki, Béla; Bates, Jason H T

    2011-04-01

    The mechanical properties of lung parenchymal tissue are both elastic and dissipative, as well as being highly nonlinear. These properties cannot be fully understood, however, in terms of the individual constituents of the tissue. Rather, the mechanical behavior of lung tissue emerges as a macroscopic phenomenon from the interactions of its microscopic components in a way that is neither intuitive nor easily understood. In this review, we first consider the quasi-static mechanical behavior of lung tissue and discuss computational models that show how smooth nonlinear stress-strain behavior can arise through a percolation-like process in which the sequential recruitment of collagen fibers with increasing strain causes them to progressively take over the load-bearing role from elastin. We also show how the concept of percolation can be used to link the pathologic progression of parenchymal disease at the micro scale to physiological symptoms at the macro scale. We then examine the dynamic mechanical behavior of lung tissue, which invokes the notion of tissue resistance. Although usually modeled phenomenologically in terms of collections of springs and dashpots, lung tissue viscoelasticity again can be seen to reflect various types of complex dynamic interactions at the molecular level. Finally, we discuss the inevitability of why lung tissue mechanics need to be complex.

  9. Dynamics of cancerous tissue correlates with invasiveness

    Science.gov (United States)

    West, Ann-Katrine Vransø; Wullkopf, Lena; Christensen, Amalie; Leijnse, Natascha; Tarp, Jens Magelund; Mathiesen, Joachim; Erler, Janine Terra; Oddershede, Lene Broeng

    2017-03-01

    Two of the classical hallmarks of cancer are uncontrolled cell division and tissue invasion, which turn the disease into a systemic, life-threatening condition. Although both processes are studied, a clear correlation between cell division and motility of cancer cells has not been described previously. Here, we experimentally characterize the dynamics of invasive and non-invasive breast cancer tissues using human and murine model systems. The intrinsic tissue velocities, as well as the divergence and vorticity around a dividing cell correlate strongly with the invasive potential of the tissue, thus showing a distinct correlation between tissue dynamics and aggressiveness. We formulate a model which treats the tissue as a visco-elastic continuum. This model provides a valid reproduction of the cancerous tissue dynamics, thus, biological signaling is not needed to explain the observed tissue dynamics. The model returns the characteristic force exerted by an invading cell and reveals a strong correlation between force and invasiveness of breast cancer cells, thus pinpointing the importance of mechanics for cancer invasion.

  10. PATMA: parser of archival tissue microarray

    Directory of Open Access Journals (Sweden)

    Lukasz Roszkowiak

    2016-12-01

    Full Text Available Tissue microarrays are commonly used in modern pathology for cancer tissue evaluation, as it is a very potent technique. Tissue microarray slides are often scanned to perform computer-aided histopathological analysis of the tissue cores. For processing the image, splitting the whole virtual slide into images of individual cores is required. The only way to distinguish cores corresponding to specimens in the tissue microarray is through their arrangement. Unfortunately, distinguishing the correct order of cores is not a trivial task as they are not labelled directly on the slide. The main aim of this study was to create a procedure capable of automatically finding and extracting cores from archival images of the tissue microarrays. This software supports the work of scientists who want to perform further image processing on single cores. The proposed method is an efficient and fast procedure, working in fully automatic or semi-automatic mode. A total of 89% of punches were correctly extracted with automatic selection. With an addition of manual correction, it is possible to fully prepare the whole slide image for extraction in 2 min per tissue microarray. The proposed technique requires minimum skill and time to parse big array of cores from tissue microarray whole slide image into individual core images.

  11. DOPA, norepinephrine, and dopamine in rat tissues

    DEFF Research Database (Denmark)

    Eldrup, E; Richter, Erik; Christensen, N J

    1989-01-01

    in the gastrointestinal tract, kidney, and spleen. No correlations were obtained between the tissue concentration of DOPA and NE. A DA-to-NE ratio approximately 1% was observed in liver, muscle, pancreas, spleen, and heart, whereas we found exponentially increasing DA values with increasing NE concentration in tissues...

  12. Taurine content of tissues of irradiated rats

    International Nuclear Information System (INIS)

    Akhalaya, M.Ya.; Bogatyrev, G.P.; Kudryashov, Yu.B.; Yartsev, E.I.

    1976-01-01

    The taurine content of tissues (liver, stomach, small intestine and spleen) of rats irradiated with doses of 700 and 450 rads has been studied. Phase changes have been found in the taurine content of radiosensitive tissues in the course of radiation injury development

  13. [Metastatic hypernephroma in oral soft tissue].

    Science.gov (United States)

    Martínez Conde, R; López Cedrún, J L; Aguirre Urízar, J M; Rosell Cerro, M; Llarena Ibarguren, R

    1990-05-01

    Oral metastatic tumors are rare. A case of primary affection of oral soft tissues by metastatic hypernefroma, without radiologic evidence of bone involvement, is presented in this paper. Review of the literature reveals that the gingiva is the commonest location of metastatic hypernephroma in the oral soft tissues. The most important clinicopathology and therapeutic features are also reviewed.

  14. Nanomaterials for Craniofacial and Dental Tissue Engineering.

    Science.gov (United States)

    Li, G; Zhou, T; Lin, S; Shi, S; Lin, Y

    2017-07-01

    Tissue engineering shows great potential as a future treatment for the craniofacial and dental defects caused by trauma, tumor, and other diseases. Due to the biomimetic features and excellent physiochemical properties, nanomaterials are of vital importance in promoting cell growth and stimulating tissue regeneration in tissue engineering. For craniofacial and dental tissue engineering, the frequently used nanomaterials include nanoparticles, nanofibers, nanotubes, and nanosheets. Nanofibers are attractive for cell invasion and proliferation because of their resemblance to extracellular matrix and the presence of large pores, and they have been used as scaffolds in bone, cartilage, and tooth regeneration. Nanotubes and nanoparticles improve the mechanical and chemical properties of scaffold, increase cell attachment and migration, and facilitate tissue regeneration. In addition, nanofibers and nanoparticles are also used as a delivery system to carry the bioactive agent in bone and tooth regeneration, have better control of the release speed of agent upon degradation of the matrix, and promote tissue regeneration. Although applications of nanomaterials in tissue engineering remain in their infancy with numerous challenges to face, the current results indicate that nanomaterials have massive potential in craniofacial and dental tissue engineering.

  15. Nonlinear spectral imaging of biological tissues

    NARCIS (Netherlands)

    Palero, J.A.

    2007-01-01

    The work presented in this thesis demonstrates live high resolution 3D imaging of tissue in its native state and environment. The nonlinear interaction between focussed femtosecond light pulses and the biological tissue results in the emission of natural autofluorescence and second-harmonic signal.

  16. Nonlinear spectral imaging of biological tissues

    Science.gov (United States)

    Palero, J. A.

    2007-07-01

    The work presented in this thesis demonstrates live high resolution 3D imaging of tissue in its native state and environment. The nonlinear interaction between focussed femtosecond light pulses and the biological tissue results in the emission of natural autofluorescence and second-harmonic signal. Because biological intrinsic emission is generally very weak and extends from the ultraviolet to the visible spectral range, a broad-spectral range and high sensitivity 3D spectral imaging system is developed. Imaging the spectral characteristics of the biological intrinsic emission reveals the structure and biochemistry of the cells and extra-cellular components. By using different methods in visualizing the spectral images, discrimination between different tissue structures is achieved without the use of any stain or fluorescent label. For instance, RGB real color spectral images of the intrinsic emission of mouse skin tissues show blue cells, green hair follicles, and purple collagen fibers. The color signature of each tissue component is directly related to its characteristic emission spectrum. The results of this study show that skin tissue nonlinear intrinsic emission is mainly due to the autofluorescence of reduced nicotinamide adenine dinucleotide (phosphate), flavins, keratin, melanin, phospholipids, elastin and collagen and nonlinear Raman scattering and second-harmonic generation in Type I collagen. In vivo time-lapse spectral imaging is implemented to study metabolic changes in epidermal cells in tissues. Optical scattering in tissues, a key factor in determining the maximum achievable imaging depth, is also investigated in this work.

  17. DNA from keratinous tissue. Part I

    DEFF Research Database (Denmark)

    Bengtsson, Camilla Friis; Olsen, Maia E.; Brandt, Luise Ørsted

    2012-01-01

    genetic analyses, the fact that sampling generally causes minimal visual damage to valuable specimens. Even when freshly sampled, however, the DNA quantity and quality in the fully keratinized parts of such tissues is extremely poor in comparison to other tissues such as blood and muscle - although little...

  18. Adipose Tissue Biology: An Update Review

    Directory of Open Access Journals (Sweden)

    Anna Meiliana

    2009-12-01

    Full Text Available BACKGROUND: Obesity is a major health problem in most countries in the world today. It increases the risk of diabetes, heart disease, fatty liver and some form of cancer. Adipose tissue biology is currently one of the “hot” areas of biomedical science, as fundamental for the development of novel therapeutics for obesity and its related disorders.CONTENT: Adipose tissue consist predominantly of adipocytes, adipose-derived stromal cells (ASCs, vascular endothelial cells, pericytes, fibroblast, macrophages, and extracellular matrix. Adipose tissue metabolism is extremely dynamic, and the supply of and removal of substrates in the blood is acutely regulated according to the nutritional state. Adipose tissue possesses the ability to a very large extent to modulate its own metabolic activities including differentiation of new adipocytes and production of blood vessels as necessary to accommodate increasing fat stores. At the same time, adipocytes signal to other tissue to regulate their energy metabolism in accordance with the body's nutritional state. Ultimately adipocyte fat stores have to match the body's overall surplus or deficit of energy. Obesity causes adipose tissue dysfunction and results in obesity-related disorders. SUMMARY: It is now clear that adipose tissue is a complex and highly active metabolic and endocrine organ. Undestanding the molecular mechanisms underlying obesity and its associated disease cluster is also of great significance as the need for new and more effective therapeutic strategies is more urgent than ever.  KEYWORDS: obesity, adipocyte, adipose, tissue, adipogenesis, angiogenesis, lipid droplet, lipolysis, plasticity, dysfunction.

  19. PLANT REGENERATION THROUGH TISSUE CULTURE OF PEAR ...

    African Journals Online (AJOL)

    AISA

    culture media, calli embryogenic potential and fertile plants regeneration were conserved for more than 12 months. Characteristics of regenerated plants were similar to control. It appears that dissected shoot apex was a new appropriate tool in tissue culture. Key words: Tissue culture, culture medium, callus induction, shoot ...

  20. Plant Tissue Culture in a Bag.

    Science.gov (United States)

    Beck, Mike

    2000-01-01

    Describes the use of an oven bag as a sterile chamber for culture initiation and tissue transfer. Plant tissue culture is an ideal tool for introducing students to plants, cloning, and experimental design. Includes materials, methods, discussion, and conclusion sections. (SAH)

  1. Injectable silk foams for soft tissue regeneration.

    Science.gov (United States)

    Bellas, Evangelia; Lo, Tim J; Fournier, Eric P; Brown, Joseph E; Abbott, Rosalyn D; Gil, Eun S; Marra, Kacey G; Rubin, J Peter; Leisk, Gary G; Kaplan, David L

    2015-02-18

    Soft tissue fillers are needed for restoration of a defect or augmentation of existing tissues. Autografts and lipotransfer have been under study for soft tissue reconstruction but yield inconsistent results, often with considerable resorption of the grafted tissue. A minimally invasive procedure would reduce scarring and recovery time as well as allow the implant and/or grafted tissue to be placed closer to existing vasculature. Here, the feasibility of an injectable silk foam for soft tissue regeneration is demonstrated. Adipose-derived stem cells survive and migrate through the foam over a 10-d period in vitro. The silk foams are also successfully injected into the subcutaneous space in a rat and over a 3-month period integrating with the surrounding native tissue. The injected foams are palpable and soft to the touch through the skin and returning to their original dimensions after pressure is applied and then released. The foams readily absorb lipoaspirate making the foams useful as a scaffold or template for existing soft tissue filler technologies, useful either as a biomaterial alone or in combination with the lipoaspirate. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Identification, tissue distribution and evaluation of brain ...

    Indian Academy of Sciences (India)

    Prakash

    (Murashita et al. 2009) and, as reported in Atlantic cod, seven days of fasting did not increase NPY gene expression. (Kehoe and Volkoff 2007). NPY expression has also been detected in the intestine, liver, spleen, muscle and adipose tissue of fish (Liang et al. 2007) but little information about its function on these tissues is ...

  3. Walnut tissue culture: research and field applications

    Science.gov (United States)

    2004-01-01

    Vitrotech Biotecnologia Vegetal began researching propagating Juglans regia (English walnut) and various Juglans hybrids by tissue culture in 1993 and has operated on a commercial scale since 1996. Since this time, more than one and a half million walnuts of different species have been propagated and field planted. Tissue cultured...

  4. Single domain antibodies in tissue engineering

    NARCIS (Netherlands)

    Rodrigues, E.D.

    2014-01-01

    The aim of this thesis is to demonstrate the potential of VHH in tissue engineering applications, with a focus on bone and cartilage tissue regeneration. After a general introduction to this thesis in chapter 1, the selection of VHH targeting growth factors is described in chapter 2. VHH were

  5. Design Strategies for Tissue Engineering Scaffolds

    NARCIS (Netherlands)

    Papenburg, B.J.

    2009-01-01

    This thesis focuses on various aspects involved in scaffold design and the cell-scaffold interaction. The ultimate goal is to design a scaffold that supports functional tissue formation, resembling in vivo tissue organization, combined with good nutrient supply to the cells. In our concept 3D

  6. Multispectral tissue characterization for intestinal anastomosis optimization

    Science.gov (United States)

    Cha, Jaepyeong; Shademan, Azad; Le, Hanh N. D.; Decker, Ryan; Kim, Peter C. W.; Kang, Jin U.; Krieger, Axel

    2015-10-01

    Intestinal anastomosis is a surgical procedure that restores bowel continuity after surgical resection to treat intestinal malignancy, inflammation, or obstruction. Despite the routine nature of intestinal anastomosis procedures, the rate of complications is high. Standard visual inspection cannot distinguish the tissue subsurface and small changes in spectral characteristics of the tissue, so existing tissue anastomosis techniques that rely on human vision to guide suturing could lead to problems such as bleeding and leakage from suturing sites. We present a proof-of-concept study using a portable multispectral imaging (MSI) platform for tissue characterization and preoperative surgical planning in intestinal anastomosis. The platform is composed of a fiber ring light-guided MSI system coupled with polarizers and image analysis software. The system is tested on ex vivo porcine intestine tissue, and we demonstrate the feasibility of identifying optimal regions for suture placement.

  7. Aloe Vera for Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Shekh Rahman

    2017-02-01

    Full Text Available Aloe vera, also referred as Aloe barbadensis Miller, is a succulent plant widely used for biomedical, pharmaceutical and cosmetic applications. Aloe vera has been used for thousands of years. However, recent significant advances have been made in the development of aloe vera for tissue engineering applications. Aloe vera has received considerable attention in tissue engineering due to its biodegradability, biocompatibility, and low toxicity properties. Aloe vera has been reported to have many biologically active components. The bioactive components of aloe vera have effective antibacterial, anti-inflammatory, antioxidant, and immune-modulatory effects that promote both tissue regeneration and growth. The aloe vera plant, its bioactive components, extraction and processing, and tissue engineering prospects are reviewed in this article. The use of aloe vera as tissue engineering scaffolds, gels, and films is discussed, with a special focus on electrospun nanofibers.

  8. Aloe Vera for Tissue Engineering Applications.

    Science.gov (United States)

    Rahman, Shekh; Carter, Princeton; Bhattarai, Narayan

    2017-02-14

    Aloe vera, also referred as Aloe barbadensis Miller, is a succulent plant widely used for biomedical, pharmaceutical and cosmetic applications. Aloe vera has been used for thousands of years. However, recent significant advances have been made in the development of aloe vera for tissue engineering applications. Aloe vera has received considerable attention in tissue engineering due to its biodegradability, biocompatibility, and low toxicity properties. Aloe vera has been reported to have many biologically active components. The bioactive components of aloe vera have effective antibacterial, anti-inflammatory, antioxidant, and immune-modulatory effects that promote both tissue regeneration and growth. The aloe vera plant, its bioactive components, extraction and processing, and tissue engineering prospects are reviewed in this article. The use of aloe vera as tissue engineering scaffolds, gels, and films is discussed, with a special focus on electrospun nanofibers.

  9. Bone tissue bioprinting for craniofacial reconstruction.

    Science.gov (United States)

    Datta, Pallab; Ozbolat, Veli; Ayan, Bugra; Dhawan, Aman; Ozbolat, Ibrahim T

    2017-11-01

    Craniofacial (CF) tissue is an architecturally complex tissue consisting of both bone and soft tissues with significant patient specific variations. Conditions of congenital abnormalities, tumor resection surgeries, and traumatic injuries of the CF skeleton can result in major deficits of bone tissue. Despite advances in surgical reconstruction techniques, management of CF osseous deficits remains a challenge. Due its inherent versatility, bioprinting offers a promising solution to address these issues. In this review, we present and analyze the current state of bioprinting of bone tissue and highlight how these techniques may be adapted to serve regenerative therapies for CF applications. Biotechnol. Bioeng. 2017;114: 2424-2431. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  10. Grating-based tomography of human tissues

    Science.gov (United States)

    Müller, Bert; Schulz, Georg; Mehlin, Andrea; Herzen, Julia; Lang, Sabrina; Holme, Margaret; Zanette, Irene; Hieber, Simone; Deyhle, Hans; Beckmann, Felix; Pfeiffer, Franz; Weitkamp, Timm

    2012-07-01

    The development of therapies to improve our health requires a detailed knowledge on the anatomy of soft tissues from the human body down to the cellular level. Grating-based phase contrast micro computed tomography using synchrotron radiation provides a sensitivity, which allows visualizing micrometer size anatomical features in soft tissue without applying any contrast agent. We show phase contrast tomography data of human brain, tumor vessels and constricted arteries from the beamline ID 19 (ESRF) and urethral tissue from the beamline W2 (HASYLAB/DESY) with micrometer resolution. Here, we demonstrate that anatomical features can be identified within brain tissue as well known from histology. Using human urethral tissue, the application of two photon energies is compared. Tumor vessels thicker than 20 μm can be perfectly segmented. The morphology of coronary arteries can be better extracted in formalin than after paraffin embedding.

  11. Studying cytokinesis in Drosophila epithelial tissues.

    Science.gov (United States)

    Pinheiro, D; Bellaïche, Y

    2017-01-01

    Epithelial tissue cohesiveness is ensured through cell-cell junctions that maintain both adhesion and mechanical coupling between neighboring cells. During development, epithelial tissues undergo intensive cell proliferation. Cell division, and particularly cytokinesis, is coupled to the formation of new adhesive contacts, thereby preserving tissue integrity and propagating cell polarity. Remarkably, the geometry of the new interfaces is determined by the combined action of the dividing cell and its neighbors. To further understand the interplay between the dividing cell and its neighbors, as well as the role of cell division for tissue morphogenesis, it is important to analyze cytokinesis in vivo. Here we present methods to perform live imaging of cell division in Drosophila epithelial tissues and discuss some aspects of image processing and analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Aloe Vera for Tissue Engineering Applications

    Science.gov (United States)

    Rahman, Shekh; Carter, Princeton; Bhattarai, Narayan

    2017-01-01

    Aloe vera, also referred as Aloe barbadensis Miller, is a succulent plant widely used for biomedical, pharmaceutical and cosmetic applications. Aloe vera has been used for thousands of years. However, recent significant advances have been made in the development of aloe vera for tissue engineering applications. Aloe vera has received considerable attention in tissue engineering due to its biodegradability, biocompatibility, and low toxicity properties. Aloe vera has been reported to have many biologically active components. The bioactive components of aloe vera have effective antibacterial, anti-inflammatory, antioxidant, and immune-modulatory effects that promote both tissue regeneration and growth. The aloe vera plant, its bioactive components, extraction and processing, and tissue engineering prospects are reviewed in this article. The use of aloe vera as tissue engineering scaffolds, gels, and films is discussed, with a special focus on electrospun nanofibers. PMID:28216559

  13. Microwave processing of gustatory tissues for immunohistochemistry

    Science.gov (United States)

    Bond, Amanda; Kinnamon, John C.

    2013-01-01

    We use immunohistochemistry to study taste cell structure and function as a means to elucidate how taste receptor cells communicate with nerve fibers and adjacent taste cells. This conventional method, however, is time consuming. In the present study we used taste buds from rat circumvallate papillae to compare conventional immunohistochemical tissue processing with microwave processing for the colocalization of several biochemical pathway markers (PLCβ2, syntaxin-1, IP3R3, α-gustducin) and the nuclear stain, Sytox. The results of our study indicate that in microwave versus conventional immunocytochemistry: (1) fixation quality is improved; (2) the amount of time necessary for processing tissue is decreased; (3) antigen retrieval is no longer needed; (4) image quality is superior. In sum, microwave tissue processing of gustatory tissues is faster and superior to conventional immunohistochemical tissue processing for many applications. PMID:23473796

  14. Unit operations of tissue development: epithelial folding.

    Science.gov (United States)

    Zartman, Jeremiah J; Shvartsman, Stanislav Y

    2010-01-01

    The development of multicellular organisms relies on a small set of construction techniques-assembly, sculpting, and folding-that are spatially and temporally regulated in a combinatorial manner to produce the diversity of tissues within the body. These basic processes are well conserved across tissue types and species at the level of both genes and mechanisms. Here we review the signaling, patterning, and biomechanical transformations that occur in two well-studied model systems of epithelial folding to illustrate both the complexity and modularity of tissue development. In particular, we discuss the possibility of a spatial code specifying morphogenesis. To decipher this code, engineers and scientists need to establish quantitative experimental systems and to develop models that address mechanisms at multiple levels of organization, from gene sequence to tissue biomechanics. In turn, quantitative models of embryogenesis can inspire novel methods for creating synthetic organs and treating degenerative tissue diseases.

  15. Tissue modification with feedback: the smart scalpel

    Science.gov (United States)

    Sebern, Elizabeth L.; Brenan, Colin J. H.; Anderson, R. Rox; Hunter, Ian W.

    1998-10-01

    While feedback control is widespread throughout many engineering fields, there are almost no examples of surgical instruments that utilize a real-time detection and intervention strategy. This concept of closed loop feedback can be applied to the development of autonomous or semi- autonomous minimally invasive robotic surgical systems for efficient excision or modification of diseased tissue. Spatially localized regions of the tissue are first probed to distinguish pathological from healthy tissue based on differences in histochemical and morphological properties. Energy is directed to only the diseased tissue, minimizing collateral damage by leaving the adjacent healthy tissue intact. Continuous monitoring determines treatment effectiveness and, if needed, enables real-time treatment modifications to produce optimal therapeutic outcomes. The present embodiment of this general concept is a microsurgical instrument we call the Smart Scalpel, designed to treat skin angiodysplasias such as port wine stains. Other potential Smart Scalpel applications include psoriasis treatment and early skin cancer detection and intervention.

  16. Scaffolds for tissue engineering of cardiac valves.

    Science.gov (United States)

    Jana, S; Tefft, B J; Spoon, D B; Simari, R D

    2014-07-01

    Tissue engineered heart valves offer a promising alternative for the replacement of diseased heart valves avoiding the limitations faced with currently available bioprosthetic and mechanical heart valves. In the paradigm of tissue engineering, a three-dimensional platform - the so-called scaffold - is essential for cell proliferation, growth and differentiation, as well as the ultimate generation of a functional tissue. A foundation for success in heart valve tissue engineering is a recapitulation of the complex design and diverse mechanical properties of a native valve. This article reviews technological details of the scaffolds that have been applied to date in heart valve tissue engineering research. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  17. Sclerites in different tissues of Mediterranean Echinodermata.

    Science.gov (United States)

    Ocaña Martín, Amelia; Tierno de Figueroa, J Manuel; Palomino-Morales, Rogelio J

    2006-06-01

    The presence of sclerites in different mesodermal tissues was studied in thirteen species of Mediterranean echinoderms representing the five living classes. In the species of Asteroidea and Crinoidea examined, sclerites were present only in specific tissues. In the species of Ophiuroidea and, especially, Echinoidea and Holothuroidea examined, sclerites were present in almost every tissue, but with considerable variation among species and tissues. Data on sclerite shape, size, and relative abundance (measured as tissue abundance) are presented. The data support the possible functional role of sclerites as reinforcing structures, as well as their possible use as taxonomic characters. Finally, the need of more studies to elucidate the ontogenetic and phylogenetic implications of sclerites is discussed.

  18. Histological observation for needle-tissue interactions.

    Science.gov (United States)

    Nakagawa, Yoshiyuki; Koseki, Yoshihiko

    2013-01-01

    We histologically investigated tissue fractures and deformations caused by ex vivo needle insertions. The tissue was formalin-fixed while the needle remained in the tissue. Following removal of the needle, the tissue was microtomed, stained, and observed microscopically. This method enabled observations of cellular and tissular conditions where deformations caused by needle insertions were approximately preserved. For this study, our novel method presents preliminary findings related with tissue fractures and the orientation of needle blade relative to muscle fibers. When the needle blade was perpendicular to the muscle fiber, transfiber fractures and relatively large longitudinal deformations occurred. When the needle blade was parallel to the muscle fiber, interfiber fractures and relatively small longitudinal deformations occurred. This made a significant difference in the resistance force of the needle insertions.

  19. The Adipose Tissue in Farm Animals

    DEFF Research Database (Denmark)

    Sauerwein, Helga; Bendixen, Emoke; Restelli, Laura

    2014-01-01

    and metabolic disorders. We herein provide a general overview of adipose tissue functions and its importance in farm animals. This review will summarize recent achievements in farm animal adipose tissue proteomics, mainly in cattle and pigs, but also in poultry, i.e. chicken and in farmed fish. Proteomics...... and immune cells. The scientific interest in adipose tissue is largely based on the worldwide increasing prevalence of obesity in humans; in contrast, obesity is hardly an issue for farmed animals that are fed according to their well-defined needs. Adipose tissue is nevertheless of major importance...... in these animals, as the adipose percentage of the bodyweight is a major determinant for the efficiency of transferring nutrients from feed into food products and thus for the economic value from meat producing animals. In dairy animals, the importance of adipose tissue is based on its function as stromal...

  20. Collecting and Storing Tissue, Blood, and Bone Marrow Samples From Patients With Rhabdomyosarcoma or Other Soft Tissue Sarcoma

    Science.gov (United States)

    2017-12-11

    Adult Rhabdomyosarcoma; Childhood Desmoplastic Small Round Cell Tumor; Chordoma; Desmoid Tumor; Metastatic Childhood Soft Tissue Sarcoma; Nonmetastatic Childhood Soft Tissue Sarcoma; Previously Treated Childhood Rhabdomyosarcoma; Previously Untreated Childhood Rhabdomyosarcoma; Recurrent Adult Soft Tissue Sarcoma; Recurrent Childhood Rhabdomyosarcoma; Recurrent Childhood Soft Tissue Sarcoma; Stage I Adult Soft Tissue Sarcoma; Stage II Adult Soft Tissue Sarcoma; Stage III Adult Soft Tissue Sarcoma; Stage IV Adult Soft Tissue Sarcoma

  1. Assessment of tissue viability by polarization spectroscopy

    Science.gov (United States)

    Nilsson, G.; Anderson, C.; Henricson, J.; Leahy, M.; O'Doherty, J.; Sjöberg, F.

    2008-09-01

    A new and versatile method for tissue viability imaging based on polarization spectroscopy of blood in superficial tissue structures such as the skin is presented in this paper. Linearly polarized light in the visible wavelength region is partly reflected directly by the skin surface and partly diffusely backscattered from the dermal tissue matrix. Most of the directly reflected light preserves its polarization state while the light returning from the deeper tissue layers is depolarized. By the use of a polarization filter positioned in front of a sensitive CCD-array, the light directly reflected from the tissue surface is blocked, while the depolarized light returning from the deeper tissue layers reaches the detector array. By separating the colour planes of the detected image, spectroscopic information about the amount of red blood cells (RBCs) in the microvascular network of the tissue under investigation can be derived. A theory that utilizes the differences in light absorption of RBCs and bloodless tissue in the red and green wavelength region forms the basis of an algorithm for displaying a colour coded map of the RBC distribution in a tissue. Using a fluid model, a linear relationship (cc. = 0.99) between RBC concentration and the output signal was demonstrated within the physiological range 0-4%. In-vivo evaluation using transepidermal application of acetylcholine by the way of iontophoresis displayed the heterogeneity pattern of the vasodilatation produced by the vasoactive agent. Applications of this novel technology are likely to be found in drug and skin care product development as well as in the assessment of skin irritation and tissue repair processes and even ultimately in a clinic case situation.

  2. Difference in volatile composition between the pericarp tissue and inner tissue of tomato (Solanum lycopersicum) fruit

    Science.gov (United States)

    Numerous studies have reported the volatile profiles in the whole fruit or pericarp tissue of tomato (Solanum lycopersicum) fruit; however, information is limited on the volatile composition in the inner tissue and its contribution to tomato aroma. For this, the pericarps and inner tissues of “Money...

  3. The importance of establishing an international network of tissue banks and regional tissue processing centers.

    Science.gov (United States)

    Morales Pedraza, Jorge

    2014-03-01

    During the past four decades, many tissue banks have been established across the world with the aim of supplying sterilized tissues for clinical use and research purposes. Between 1972 and 2005, the International Atomic Energy Agency supported the establishment of more than sixty of these tissue banks in Latin America and the Caribbean, Asia and the Pacific, Africa and Eastern Europe; promoted the use of the ionizing radiation technique for the sterilization of the processed tissues; and encouraged cooperation between the established tissue banks during the implementation of its program on radiation and tissue banking at national, regional and international levels. Taking into account that several of the established tissue banks have gained a rich experience in the procurement, processing, sterilization, storage, and medical use of sterilized tissues, it is time now to strengthen further international and regional cooperation among interested tissue banks located in different countries. The purpose of this cooperation is to share the experience gained by these banks in the procurement, processing, sterilization, storage, and used of different types of tissues in certain medical treatments and research activities. This could be done through the establishment of a network of tissue banks and a limited number of regional tissue processing centers in different regions of the world.

  4. Scaffolding in tissue engineering: general approaches and tissue-specific considerations.

    Science.gov (United States)

    Chan, B P; Leong, K W

    2008-12-01

    Scaffolds represent important components for tissue engineering. However, researchers often encounter an enormous variety of choices when selecting scaffolds for tissue engineering. This paper aims to review the functions of scaffolds and the major scaffolding approaches as important guidelines for selecting scaffolds and discuss the tissue-specific considerations for scaffolding, using intervertebral disc as an example.

  5. Adipose tissue-derived stem cells in oral mucosa tissue engineering ...

    African Journals Online (AJOL)

    Jane

    2011-10-10

    Oct 10, 2011 ... urethral reconstruction. Specifically, tissue-engineered oral mucosa holds great prospect for urethroplasty. Mesenchymal stem cells within the stromal-vascular fraction of subcutaneous adipose tissue, that is, adipose tissue-derived stem cells (ADSCs), have been used in skin repair with satisfactory results.

  6. 21 CFR 876.5885 - Tissue culture media for human ex vivo tissue and cell culture processing applications.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tissue culture media for human ex vivo tissue and... DEVICES Therapeutic Devices § 876.5885 Tissue culture media for human ex vivo tissue and cell culture processing applications. (a) Identification. Tissue culture media for human ex vivo tissue and cell culture...

  7. Tissue/blood partition coefficients for xenon in various adipose tissue depots in man

    DEFF Research Database (Denmark)

    Bülow, J; Jelnes, Rolf; Astrup, A

    1987-01-01

    Tissue/blood partition coefficients (lambda) for xenon were calculated for subcutaneous adipose tissue from the abdominal wall and the thigh, and for the perirenal adipose tissue after chemical analysis of the tissues for lipid, water and protein content. The lambda in the perirenal tissue...... was found to correlate linearly to the relative body weight (RBW) in per cent with the regression equation lambda = 0.045 . RBW + 0.99. The subcutaneous lambda on the abdomen correlated linearly to the local skinfold thickness (SFT) with the equation lambda = 0.22 SFT + 2.99. Similarly lambda on the thigh...

  8. Next Generation Tissue Engineering of Orthopedic Soft Tissue-to-Bone Interfaces

    Science.gov (United States)

    Boys, Alexander J.; McCorry, Mary Clare; Rodeo, Scott; Bonassar, Lawrence J.; Estroff, Lara A.

    2017-01-01

    Soft tissue-to-bone interfaces are complex structures that consist of gradients of extracellular matrix materials, cell phenotypes, and biochemical signals. These interfaces, called entheses for ligaments, tendons, and the meniscus, are crucial to joint function, transferring mechanical loads and stabilizing orthopedic joints. When injuries occur to connected soft tissue, the enthesis must be re-established to restore function, but due to structural complexity, repair has proven challenging. Tissue engineering offers a promising solution for regenerating these tissues. This prospective review discusses methodologies for tissue engineering the enthesis, outlined in three key design inputs: materials processing methods, cellular contributions, and biochemical factors. PMID:29333332

  9. Superior Tissue Evolution in Slow-Degrading Scaffolds for Valvular Tissue Engineering.

    Science.gov (United States)

    Brugmans, Marieke M C P; Soekhradj-Soechit, R Sarita; van Geemen, Daphne; Cox, Martijn; Bouten, Carlijn V C; Baaijens, Frank P T; Driessen-Mol, Anita

    2016-01-01

    Synthetic polymers are widely used to fabricate porous scaffolds for the regeneration of cardiovascular tissues. To ensure mechanical integrity, a balance between the rate of scaffold absorption and tissue formation is of high importance. A higher rate of tissue formation is expected in fast-degrading materials than in slow-degrading materials. This could be a result of synthetic cells, which aim to compensate for the fast loss of mechanical integrity of the scaffold by deposition of collagen fibers. Here, we studied the effect of fast-degrading polyglycolic acid scaffolds coated with poly-4-hydroxybutyrate (PGA-P4HB) and slow-degrading poly-ɛ-caprolactone (PCL) scaffolds on amount of tissue, composition, and mechanical characteristics in time, and compared these engineered values with values for native human heart valves. Electrospun PGA-P4HB and PCL scaffolds were either kept unseeded in culture or were seeded with human vascular-derived cells. Tissue formation, extracellular matrix (ECM) composition, remaining scaffold weight, tissue-to-scaffold weight ratio, and mechanical properties were analyzed every week up to 6 weeks. Mass of unseeded PCL scaffolds remained stable during culture, whereas PGA-P4HB scaffolds degraded rapidly. When seeded with cells, both scaffold types demonstrated increasing amounts of tissue with time, which was more pronounced for PGA-P4HB-based tissues during the first 2 weeks; however, PCL-based tissues resulted in the highest amount of tissue after 6 weeks. This study is the first to provide insight into the tissue-to-scaffold weight ratio, therewith allowing for a fair comparison between engineered tissues cultured on scaffolds as well as between native heart valve tissues. Although the absolute amount of ECM components differed between the engineered tissues, the ratio between ECM components was similar after 6 weeks. PCL-based tissues maintained their shape, whereas the PGA-P4HB-based tissues deformed during culture. After 6 weeks

  10. Tissue elasticity and the ageing elastic fibre.

    Science.gov (United States)

    Sherratt, Michael J

    2009-12-01

    The ability of elastic tissues to deform under physiological forces and to subsequently release stored energy to drive passive recoil is vital to the function of many dynamic tissues. Within vertebrates, elastic fibres allow arteries and lungs to expand and contract, thus controlling variations in blood pressure and returning the pulmonary system to a resting state. Elastic fibres are composite structures composed of a cross-linked elastin core and an outer layer of fibrillin microfibrils. These two components perform distinct roles; elastin stores energy and drives passive recoil, whilst fibrillin microfibrils direct elastogenesis, mediate cell signalling, maintain tissue homeostasis via TGFβ sequestration and potentially act to reinforce the elastic fibre. In many tissues reduced elasticity, as a result of compromised elastic fibre function, becomes increasingly prevalent with age and contributes significantly to the burden of human morbidity and mortality. This review considers how the unique molecular structure, tissue distribution and longevity of elastic fibres pre-disposes these abundant extracellular matrix structures to the accumulation of damage in ageing dermal, pulmonary and vascular tissues. As compromised elasticity is a common feature of ageing dynamic tissues, the development of strategies to prevent, limit or reverse this loss of function will play a key role in reducing age-related morbidity and mortality.

  11. Cellular basis of tissue regeneration by omentum.

    Directory of Open Access Journals (Sweden)

    Shivanee Shah

    Full Text Available The omentum is a sheet-like tissue attached to the greater curvature of the stomach and contains secondary lymphoid organs called milky spots. The omentum has been used for its healing potential for over 100 years by transposing the omental pedicle to injured organs (omental transposition, but the mechanism by which omentum helps the healing process of damaged tissues is not well understood. Omental transposition promotes expansion of pancreatic islets, hepatocytes, embryonic kidney, and neurons. Omental cells (OCs can be activated by foreign bodies in vivo. Once activated, they become a rich source for growth factors and express pluripotent stem cell markers. Moreover, OCs become engrafted in injured tissues suggesting that they might function as stem cells.Omentum consists of a variety of phenotypically and functionally distinctive cells. To understand the mechanism of tissue repair support by the omentum in more detail, we analyzed the cell subsets derived from the omentum on immune and inflammatory responses. Our data demonstrate that the omentum contains at least two groups of cells that support tissue repair, immunomodulatory myeloid derived suppressor cells and omnipotent stem cells that are indistinguishable from mesenchymal stem cells. Based on these data, we propose that the omentum is a designated organ for tissue repair and healing in response to foreign invasion and tissue damage.

  12. Force generation within tissues during development

    Science.gov (United States)

    Kasza, Karen

    During embryonic development, multicellular tissues physically change shape, move, and grow. Changes in epithelial tissue organization are often accomplished by local movements of cells that are driven largely by forces generated by the motor protein myosin II. These forces are patterned to orient cell movements, resulting in changes in tissue shape and organization to build functional tissues and organs. To investigate the mechanisms of force generation in vivo, we use the fruit fly embryo as a model system. Spatial patterns of forces orient cell movements to drive rapid tissue elongation along the head-to-tail axis of the embryo. I will describe how studying embryos generated with engineered myosin variants provides insight into where, when, and how forces are generated to efficiently reorganize tissues. We found that a myosin variant that is locked-in to the active or ``on'' state accelerates cell movements, while two mutant myosin variants associated with human disease produce slowed cell movement. These myosin variants all disrupt tissue elongation, but live imaging and biophysical measurements reveal distinct effects on myosin organization and dynamics within cells and uncover mechanisms that control the spatial and temporal patterns of force generation. These studies shed light not only on how defects in force generation contribute to disease but also on physical principles at work in active, living materials.

  13. Nonspecificity of Chronic Soft Tissue Pain Syndromes

    Directory of Open Access Journals (Sweden)

    Eldon Tunks

    1997-01-01

    Full Text Available Persistent (or chronic pain occurs with a prevalence of about 10% in the adult population, and chronic soft tissue pain is especially problematic. Criteria for diagnosis of these soft tissue pain disorders appear to suffer from specificity problems, even though they appear to be sensitive in distinguishing normal from soft tissue pain sufferers. A few decades ago the term 'neuraesthenia' was used as a diagnosis in individuals who now would probably be diagnosed as suffering from fibromyalgia, chronic fatigue and anxiety disorders with fatigue. Soft tissue pain provokes skepticism, especially among third-party payers, and controversy among clinicians. Recent epidemiological studies have demonstrated sex differences in the prevalence of widespread pain and multiple tender points, which are distributed variably throughout the adult population and tend to be correlated with subjective symptoms. Although there is a tendency for these syndromes to persist, follow-up studies show that they tend to vary in extent and sometimes show remissions over longer follow-up, casting doubt about the distinctions between chronic diffuse pains and localized chronic soft tissue pains. Because both accidents and soft tissue pains are relatively prevalent problems, the possibility of chance coincidence of accident and chronic soft tissue pain in an individual creates the need to be cautious in attributing these syndromes to specific accidents in medicolegal situations. At the same time, the available evidence does not support a generally dismissive attitude towards these patients.

  14. Adipose Tissue Remodeling as Homeostatic Inflammation

    Directory of Open Access Journals (Sweden)

    Michiko Itoh

    2011-01-01

    Full Text Available Evidence has accumulated indicating that obesity is associated with a state of chronic, low-grade inflammation. Obese adipose tissue is characterized by dynamic changes in cellular composition and function, which may be referred to as “adipose tissue remodeling”. Among stromal cells in the adipose tissue, infiltrated macrophages play an important role in adipose tissue inflammation and systemic insulin resistance. We have demonstrated that a paracrine loop involving saturated fatty acids and tumor necrosis factor-α derived from adipocytes and macrophages, respectively, aggravates obesity-induced adipose tissue inflammation. Notably, saturated fatty acids, which are released from hypertrophied adipocytes via the macrophage-induced lipolysis, serve as a naturally occurring ligand for Toll-like receptor 4 complex, thereby activating macrophages. Such a sustained interaction between endogenous ligands derived from parenchymal cells and pathogen sensors expressed in stromal immune cells should lead to chronic inflammatory responses ranging from the basal homeostatic state to diseased tissue remodeling, which may be referred to as “homeostatic inflammation”. We, therefore, postulate that adipose tissue remodeling may represent a prototypic example of homeostatic inflammation. Understanding the molecular mechanism underlying homeostatic inflammation may lead to the identification of novel therapeutic strategies to prevent or treat obesity-related complications.

  15. Glutathione turnover in 14 rat tissues

    International Nuclear Information System (INIS)

    Potter, D.W.; Tran, T.

    1990-01-01

    GSH is a tripeptide found in all tissues and is important in maintaining cellular redox status. First-order rate constants for GSH turnover were determined for various tissues of Fischer male rats. Animals were administered [ 35 S]Cys by tail vein injection and GSH turnover was estimated by the decrease in GSH specific activity following incorporation of Cys, 1-102 hr after administration. Tissue nonprotein sulfhydryls (NPSH) were detected by Ellman's assay and compared with GSH and Cys concentrations determined by HPLC with electrochemical detection. [ 35 S]GSH was analyzed by HPLC equipped with a flow-through radioactivity detector. Although total GSH and Cys were usually slightly lower than NPSH concentrations for the tissues examined, both assay systems gave comparable results. An exception was the glandular stomach which had approximately 2-fold higher NPSH. Liver and kidney had rapid turnover rates with GSH half-lives between 2-5 hr, while heart and skeletal muscle tissue had half-lives of 80-90 hr. Turnover in the blood was slowest, with a half-life of 170 hr. Gastrointestinal tract tissues were shown to have intermediate turnover rates of the following order: glandular stomach > duodenum = small intestine = caecum = large intestine = colon > forestomach. GSH half-life in lung and skin was approximately 45 hr. These studies indicate that tissues utilize GSH at markedly different rates

  16. Myocardial Tissue Engineering for Regenerative Applications.

    Science.gov (United States)

    Fujita, Buntaro; Zimmermann, Wolfram-Hubertus

    2017-09-01

    This review provides an overview of the current state of tissue-engineered heart repair with a special focus on the anticipated modes of action of tissue-engineered therapy candidates and particular implications as to transplant immunology. Myocardial tissue engineering technologies have made tremendous advances in recent years. Numerous different strategies are under investigation and have reached different stages on their way to clinical translation. Studies in animal models demonstrated that heart repair requires either remuscularization by delivery of bona fide cardiomyocytes or paracrine support for the activation of endogenous repair mechanisms. Tissue engineering approaches result in enhanced cardiomyocyte retention and sustained remuscularization, but may also be explored for targeted paracrine or mechanical support. Some of the more advanced tissue engineering approaches are already tested clinically; others are at late stages of pre-clinical development. Process optimization towards cGMP compatibility and clinical scalability of contractile engineered human myocardium is an essential step towards clinical translation. Long-term allograft retention can be achieved under immune suppression. HLA matching may be an option to enhance graft retention and reduce the need for comprehensive immune suppression. Tissue-engineered heart repair is entering the clinical stage of the translational pipeline. Like in any effective therapy, side effects must be anticipated and carefully controlled. Allograft implantation under immune suppression is the most likely clinical scenario. Strategies to overcome transplant rejection are evolving and may further boost the clinical acceptance of tissue-engineered heart repair.

  17. Multiscale Characterization of Engineered Cardiac Tissue Architecture.

    Science.gov (United States)

    Drew, Nancy K; Johnsen, Nicholas E; Core, Jason Q; Grosberg, Anna

    2016-11-01

    In a properly contracting cardiac muscle, many different subcellular structures are organized into an intricate architecture. While it has been observed that this organization is altered in pathological conditions, the relationship between length-scales and architecture has not been properly explored. In this work, we utilize a variety of architecture metrics to quantify organization and consistency of single structures over multiple scales, from subcellular to tissue scale as well as correlation of organization of multiple structures. Specifically, as the best way to characterize cardiac tissues, we chose the orientational and co-orientational order parameters (COOPs). Similarly, neonatal rat ventricular myocytes were selected for their consistent architectural behavior. The engineered cells and tissues were stained for four architectural structures: actin, tubulin, sarcomeric z-lines, and nuclei. We applied the orientational metrics to cardiac cells of various shapes, isotropic cardiac tissues, and anisotropic globally aligned tissues. With these novel tools, we discovered: (1) the relationship between cellular shape and consistency of self-assembly; (2) the length-scales at which unguided tissues self-organize; and (3) the correlation or lack thereof between organization of actin fibrils, sarcomeric z-lines, tubulin fibrils, and nuclei. All of these together elucidate some of the current mysteries in the relationship between force production and architecture, while raising more questions about the effect of guidance cues on self-assembly function. These types of metrics are the future of quantitative tissue engineering in cardiovascular biomechanics.

  18. Tubular heart valves from decellularized engineered tissue.

    Science.gov (United States)

    Syedain, Zeeshan H; Meier, Lee A; Reimer, Jay M; Tranquillo, Robert T

    2013-12-01

    A novel tissue-engineered heart valve (TEHV) was fabricated from a decellularized tissue tube mounted on a frame with three struts, which upon back-pressure cause the tube to collapse into three coapting "leaflets." The tissue was completely biological, fabricated from ovine fibroblasts dispersed within a fibrin gel, compacted into a circumferentially aligned tube on a mandrel, and matured using a bioreactor system that applied cyclic distension. Following decellularization, the resulting tissue possessed tensile mechanical properties, mechanical anisotropy, and collagen content that were comparable to native pulmonary valve leaflets. When mounted on a custom frame and tested within a pulse duplicator system, the tubular TEHV displayed excellent function under both aortic and pulmonary conditions, with minimal regurgitant fractions and transvalvular pressure gradients at peak systole, as well as well as effective orifice areas exceeding those of current commercially available valve replacements. Short-term fatigue testing of one million cycles with pulmonary pressure gradients was conducted without significant change in mechanical properties and no observable macroscopic tissue deterioration. This study presents an attractive potential alternative to current tissue valve replacements due to its avoidance of chemical fixation and utilization of a tissue conducive to recellularization by host cell infiltration.

  19. Tissue banking, biovigilance and the notify library.

    Science.gov (United States)

    Strong, D Michael

    2017-06-30

    This issue is dedicated to the contributions of Professor Glyn O. Phillips to the field of tissue banking and the advancement of science in general. The use of ionizing radiation to sterilize medical products drew the interest of the International Atomic Energy Agency (IAEA). A meeting in 1976 in Athens Greece to present work on the effects of sterilizing radiation doses upon the antigenic properties of proteins and biologic tissues was my first introduction of Professor Phillips and the role that he was to play in Tissue Banking (Friedlaender, in Phillips GO, Tallentine AN (eds) Radiation sterilization. Irradiated tissues and their potential clinical use. The North E. Wales Institute, Clwyd, p 128, 1978). The IAEA sponsored subsequent meetings in the Republic of Korea, Czechoslovakia and Rangoon, the later including a visit to the tissue bank by Professor Phillips. His advocacy resulted in multiple workshops and teaching opportunities in a variety of countries, one of which led to the establishment of the Asia Pacific Surgical Tissue Banking Association in 1989 (Phillips and Strong, in Phillips GO, Strong DM, von Versen R, Nather A (eds) Advances in tissue banking, vol 3. World Scientific, Singapore, pp 403-417, 1999).

  20. Trends in Tissue Engineering for Blood Vessels

    Science.gov (United States)

    Nemeno-Guanzon, Judee Grace; Lee, Soojung; Berg, Johan Robert; Jo, Yong Hwa; Yeo, Jee Eun; Nam, Bo Mi; Koh, Yong-Gon; Lee, Jeong Ik

    2012-01-01

    Over the years, cardiovascular diseases continue to increase and affect not only human health but also the economic stability worldwide. The advancement in tissue engineering is contributing a lot in dealing with this immediate need of alleviating human health. Blood vessel diseases are considered as major cardiovascular health problems. Although blood vessel transplantation is the most convenient treatment, it has been delimited due to scarcity of donors and the patient's conditions. However, tissue-engineered blood vessels are promising alternatives as mode of treatment for blood vessel defects. The purpose of this paper is to show the importance of the advancement on biofabrication technology for treatment of soft tissue defects particularly for vascular tissues. This will also provide an overview and update on the current status of tissue reconstruction especially from autologous stem cells, scaffolds, and scaffold-free cellular transplantable constructs. The discussion of this paper will be focused on the historical view of cardiovascular tissue engineering and stem cell biology. The representative studies featured in this paper are limited within the last decade in order to trace the trend and evolution of techniques for blood vessel tissue engineering. PMID:23251085

  1. Soft tissue and esthetic considerations around implants

    Directory of Open Access Journals (Sweden)

    Joann Pauline George

    2015-01-01

    Full Text Available The health of the peri – implant tissues play an important in the long term outcome of dental implants. The absence of keratinized gingiva (KG may be a risk factor for developing recession or peri –implantitis. However there is still ambiguity in the need for keratinized gingiva around dental implants. The preservation and reconstruction of soft tissue around dental implants is an integral component of dental Implantology. There is no long-term evidence whether augmented soft tissues can be maintained over time and are able to influence the peri-implant bone levels. Among the various soft tissue augmentation techniques Apically positioned flap with vestibuloplasty , Free gingival grafts and Connective tissue grafts are documented as the most predictable methods to increase the width of KG. Autogenous grafts increase the soft tissue thickness and improve aesthetics compared to non-grafted sites. The aim of this review is to critically discuss the need for KG around implants and the techniques to preserve and augment KG. It is difficult to arrive at a definitive conclusion due to scarcity of well designed studies in literature. Reliable evidence is lacking to suggest the ideal soft tissue augmentation/preservation techniques. Long term randomized controlled clinical trials are needed to provide a clearer image.

  2. Hypertrophic Obesity and Subcutaneous Adipose Tissue Dysfunction

    Directory of Open Access Journals (Sweden)

    Anna Meiliana

    2014-08-01

    Full Text Available BACKGROUND: Over the past 50 years, scientists have recognized that not all adipose tissue is alike, and that health risk is associated with the location as well as the amount of body fat. Different depots are sufficiently distinct with respect to fatty-acid storage and release as to probably play unique roles in human physiology. Whether fat redistribution causes metabolic disease or whether it is a marker of underlying processes that are primarily responsible is an open question. CONTENT: The limited expandability of the subcutaneous adipose tissue leads to inappropriate adipose cell expansion (hypertrophic obesity with local inflammation and a dysregulated and insulin-resistant adipose tissue. The inability to store excess fat in the subcutaneous adipose tissue is a likely key mechanism for promoting ectopic fat accumulation in tissues and areas where fat can be stored, including the intra-abdominal and visceral areas, in the liver, epi/pericardial area, around vessels, in the myocardium, and in the skeletal muscles. Many studies have implicated ectopic fat accumulation and the associated lipotoxicity as the major determinant of the metabolic complications of obesity driving systemic insulin resistance, inflammation, hepatic glucose production, and dyslipidemia. SUMMARY: In summary, hypertrophic obesity is due to an impaired ability to recruit and differentiate available adipose precursor cells in the subcutaneous adipose tissue. Thus, the subcutaneous adipose tissue may be particular in its limited ability in certain individuals to undergo adipogenesis during weight increase. Inability to promote subcutaneous adipogenesis under periods of affluence would favor lipid overlow and ectopic fat accumulation with negative metabolic consequences. KEYWORDS: obesity, adipogenesis, subcutaneous adipose tissue, visceral adipose tissue, adipocyte dysfunction.

  3. Tissue banking: public awareness in Indonesia

    International Nuclear Information System (INIS)

    Nazly Hilmy

    1999-01-01

    Public awareness and acceptance on the benefit of Tissue Bank (TB) and its products in Indonesia are still very low, however four productive TBs are in operation by using mostly tissues from living donors. Except for medical doctors, nurses and experts who are involved in the establishment of the TB as well as who applied the products, almost nobody else understand what kind of bank this tissue bank is. Ethical in collecting tissues from non- living donors and using of this human tissues for safe medical application has several considerations that should be overcome, such as religious, legal and medical considerations. Legal and medical considerations are not very difficult to be faced. People are reluctant to give up by cutting off the needed tissue of a dead relative to help someone else who is suffering from a life threatening disease. Our duty is to enlighten the public about this bank by means of seminars, exposition, writings and discussions. We can use the electronic mass- media or printed one to explain the necessity of this tissue bank. We also need to involve leaders of religions, government high ranking officials as well as related Government institutions. Otherwise the tissues that are needed can only be obtained from the poor, the homeless whose health condition we do not know and no relatives who can give their permission for the taking of parts of the body. This is a very unethical way. Since January 1998, Batan Research Tissue Bank together with several hospitals in Indonesia have done four seminars, two discussions, two expositions, producing leaflets and carried out training in this matter. But it is not enough. More efforts should be done

  4. Tissue identification during Pneumoperitoneum in laparoscopy

    Science.gov (United States)

    Chang, Yin; Tseng, Chi-Yang

    2015-03-01

    Pneumoperitoneum is the beginning procedure of laparoscopy to enlarge the abdominal cavity in order to allow the surgical instruments to insert for surgical purpose. However, the insertion of Veress needle is a blind fashion that could cause blood vessels or visceral injury without attention and results in undetectable internal bleeding. Seriously it may cause a life-threatened complication. We have developed a method that can monitor the tissue reflective spectrum, which can be used for tissue discrimination, in real time during the puncture of the Veress needle. The system includes a modified Veress needle which containes an optical bundle, a light spectrum analyzing and control unit. Therefore, the tissue reflective spectrum can be vivid observed and analyzed through the fiber optical technology during the procedure of the Veress needle insertion. In this study, we have measured the reflective spectra of various porcine abdominal tissues. The features of their spectra were analyzed and characterized to build up the data base and create an algorithm for tissue discrimination in laparoscopy. The results showed that the correlation coefficient (r) of the reflective spectrum can be 0.79-0.95 for the wavelength range of 350-1000 nm and 0.85-0.98 for the wavelength range of 350-650 nm in the same tissue of various samples which were obtained from different days. An alternative way for tissue discrimination is achieved through a decision making tree according to the characteristics of tissue spectrum. For single blind test the success rate is nearly 100%. It seems that both the algorithms mentioned above for tissue discrimination are all very promising. Therefore, these algorithms will be applied to in vivo study in animal in the near future.

  5. Mesenchymal Stromal Cells and Tissue-Specific Progenitor Cells: Their Role in Tissue Homeostasis

    Directory of Open Access Journals (Sweden)

    Aleksandra Klimczak

    2016-01-01

    Full Text Available Multipotent mesenchymal stromal/stem cells (MSCs reside in many human organs and comprise heterogeneous population of cells with self-renewal ability. These cells can be isolated from different tissues, and their morphology, immunophenotype, and differentiation potential are dependent on their tissue of origin. Each organ contains specific population of stromal cells which maintain regeneration process of the tissue where they reside, but some of them have much more wide plasticity and differentiate into multiple cells lineage. MSCs isolated from adult human tissues are ideal candidates for tissue regeneration and tissue engineering. However, MSCs do not only contribute to structurally tissue repair but also MSC possess strong immunomodulatory and anti-inflammatory properties and may influence in tissue repair by modulation of local environment. This paper is presenting an overview of the current knowledge of biology of tissue-resident mesenchymal stromal and progenitor cells (originated from bone marrow, liver, skeletal muscle, skin, heart, and lung associated with tissue regeneration and tissue homeostasis.

  6. Tissue Harmonic Synthetic Aperture Ultrasound Imaging

    DEFF Research Database (Denmark)

    Hemmsen, Martin Christian; Rasmussen, Joachim; Jensen, Jørgen Arendt

    2014-01-01

    Synthetic aperture sequential beamforming (SASB) and tissue har- monic imaging (THI) are combined to improve the image quality of medical ultrasound imaging. The technique is evaluated in a compar- ative study against dynamic receive focusing (DRF). The objective is to investigate if SASB combined......, and data were recorded with and without pulse inversion for tissue harmonic imaging. Data were acquired using a Sound Technol- ogy 192 element convex array transducer from both a wire phantom and a tissue mimicking phantom to investigate spatial resolution and pen- etration. In-vivo scans were also...

  7. Effects of microwave radiation on living tissues

    Energy Technology Data Exchange (ETDEWEB)

    Surrell, J.A.; Alexander, R.C.; Cohle, S.D.; Lovell, F.R. Jr.; Wehrenberg, R.A.

    1987-08-01

    Prompted by an alleged case of child abuse resulting from microwave oven burns and the discovery of one other case, an animal model was chosen to explore microwave burn characteristics upon living, perfusing tissue. Anesthetized piglets were exposed to radiation from a standard household microwave oven for varying lengths of time, sufficient to result in full-thickness skin and visceral burns. Characteristic burn patterns were grossly identified. Biopsies studied with both light and electron microscopy demonstrated a pattern of relative layered tissue sparing. Layered tissue sparing is characterized by burned skin and muscle, with relatively unburned subcutaneous fat between these two layers. These findings have important forensic and patient care implications.

  8. HIV Persistence in Adipose Tissue Reservoirs.

    Science.gov (United States)

    Couturier, Jacob; Lewis, Dorothy E

    2018-02-01

    The purpose of this review is to examine the evidence describing adipose tissue as a reservoir for HIV-1 and how this often expansive anatomic compartment contributes to HIV persistence. Memory CD4 T cells and macrophages, the major host cells for HIV, accumulate in adipose tissue during HIV/SIV infection of humans and rhesus macaques. Whereas HIV and SIV proviral DNA is detectable in CD4 T cells of multiple fat depots in virtually all infected humans and monkeys examined, viral RNA is less frequently detected, and infected macrophages may be less prevalent in adipose tissue. However, based on viral outgrowth assays, adipose-resident CD4 T cells are latently infected with virus that is replication-competent and infectious. Additionally, adipocytes interact with CD4 T cells and macrophages to promote immune cell activation and inflammation which may be supportive for HIV persistence. Antiviral effector cells, such as CD8 T cells and NK/NKT cells, are abundant in adipose tissue during HIV/SIV infection and typically exceed CD4 T cells, whereas B cells are largely absent from adipose tissue of humans and monkeys. Additionally, CD8 T cells in adipose tissue of HIV patients are activated and have a late differentiated phenotype, with unique TCR clonotypes of less diversity relative to blood CD8 T cells. With respect to the distribution of antiretroviral drugs in adipose tissue, data is limited, but there may be class-specific penetration of fat depots. The trafficking of infected immune cells within adipose tissues is a common event during HIV/SIV infection of humans and monkeys, but the virus may be mostly transcriptionally dormant. Viral replication may occur less in adipose tissue compared to other major reservoirs, such as lymphoid tissue, but replication competence and infectiousness of adipose latent virus are comparable to other tissues. Due to the ubiquitous nature of adipose tissue, inflammatory interactions among adipocytes and CD4 T cells and macrophages, and

  9. Progress in planta transformation without tissue culture

    International Nuclear Information System (INIS)

    Gu Yunhong; Chinese Academy of Sciences, Hefei; Qin Guangyong; Huo Yuping; Yu Zengliang

    2004-01-01

    With the development of planta genetic engineering, more emphases have been laid on convenient and high efficient genetic transformation methods. And transformation without tissue culture is a prospective direction of it. In this paper, traditional transformation methods and the methods of non-tissue culture were summarized. With the exploration and application of Arabidopsis transformation mechanism, with the use of ion beam-mediated transformation invented by Chinese scientists and the development of other transformation methods, transformation methods without tissue culture and planta genetic engineering could be improved rapidly. (authors)

  10. Vascularization of soft tissue engineering constructs

    DEFF Research Database (Denmark)

    Pimentel Carletto, Rodrigo

    with mechanical properties in the range of soft tissues has not been fully achieved. My project focused on the fabrication and the active perfusion of hydrogel constructs with multi-dimensional vasculature and controlled mechanical properties targeting soft tissues. Specifically, the initial part of the research...... nanotechnology-based paradigm for engineering vascularised liver tissue for transplantation”) and the Danish National Research Foundation and Villum Foundation’s Center for Intelligent Drug delivery and sensing Using microcontainers and Nanomechanics (Danish National Research Foundation (DNRF122)....

  11. Bioreactor Technology in Cardiovascular Tissue Engineering

    Science.gov (United States)

    Mertsching, H.; Hansmann, J.

    Cardiovascular tissue engineering is a fast evolving field of biomedical science and technology to manufacture viable blood vessels, heart valves, myocar-dial substitutes and vascularised complex tissues. In consideration of the specific role of the haemodynamics of human circulation, bioreactors are a fundamental of this field. The development of perfusion bioreactor technology is a consequence of successes in extracorporeal circulation techniques, to provide an in vitro environment mimicking in vivo conditions. The bioreactor system should enable an automatic hydrodynamic regime control. Furthermore, the systematic studies regarding the cellular responses to various mechanical and biochemical cues guarantee the viability, bio-monitoring, testing, storage and transportation of the growing tissue.

  12. Tracing molecular dephasing in biological tissue

    Science.gov (United States)

    Mokim, M.; Carruba, C.; Ganikhanov, F.

    2017-10-01

    We demonstrate the quantitative spectroscopic characterization and imaging of biological tissue using coherent time-domain microscopy with a femtosecond resolution. We identify tissue constituents and perform dephasing time (T2) measurements of characteristic Raman active vibrations. This was shown in subcutaneous mouse fat embedded within collagen rich areas of the dermis and the muscle connective tissue. The demonstrated equivalent spectral resolution (methods for characterization of biological media. This provides with the important dimensions and parameters in biological media characterization and can become an effective tool in detecting minute changes in the bio-molecular composition and environment that is critical for molecular level diagnosis.

  13. Chronic Wasting Disease Positive Tissue Bank

    Science.gov (United States)

    Wright, Scott D.

    2007-01-01

    In 2005, the USGS National Wildlife Health Center entered into an agreement with the Wyoming Game and Fish Department and the Department of Veterinary Sciences at the University of Wyoming to produce a collection of positive tissues from cervids intentionally infected with chronic wasting disease. This agreement was facilitated through the University of Wyoming Cooperative Fish and Wildlife Unit. Also, the investigators on this project sampled the animals incrementally over 2 years to show changes over time, and examined tissues from the animals by immunohistochemistry. CWD positive tissues are catalogued by species, sample site and time of infection. These data and more will soon be published.

  14. Synthetic aperture tissue and flow ultrasound imaging

    DEFF Research Database (Denmark)

    Nikolov, Svetoslav

    imaging applied to medical ultrasound. It is divided into two major parts: tissue and blood flow imaging. Tissue imaging using synthetic aperture algorithms has been investigated for about two decades, but has not been implemented in medical scanners yet. Among the other reasons, the conventional scanning...... and beamformation methods are adequate for the imaging modalities in clinical use - the B-mode imaging of tissue structures, and the color mapping of blood flow. The acquisition time, however, is too long, and these methods fail to perform real-time three-dimensional scans. The synthetic transmit aperture......, on the other hand, can create a Bmode image with as little as 2 emissions, thus significantly speeding-up the scan procedure. The first part of the dissertation describes the synthetic aperture tissue imaging. It starts with an overview of the efforts previously made by other research groups. A classification...

  15. NCI’s Cooperative Human Tissue Network

    Science.gov (United States)

    Quality biospecimens are a foundational resource for cancer research. One of NCI’s longest running biospecimen programs is the Cooperative Human Tissue Network, a resource mainly for basic discovery and early translational research.

  16. Morphological changes in tissues of unerupted teeth

    Directory of Open Access Journals (Sweden)

    Yu. V. Bisyarin

    2012-08-01

    Full Text Available Morphological composition of unerupted teeth tissues was studied. The heterogeneous degree of mineralization of dentine and hypoplastic and atrophic changes of odontoblasts were determined in the result of the research.

  17. Tissue polypeptide antigen activity in cerebrospinal fluid

    DEFF Research Database (Denmark)

    Bach, F; Söletormos, Georg; Dombernowsky, P

    1991-01-01

    Tissue polypeptide antigen (TPpA) in the cerebrospinal fluid (CSF) was measured in 59 consecutive breast cancer patients with suspected central nervous system (CNS) metastases. Subsequently, we determined that 13 patients had parenchymal brain metastases, 10 had leptomeningeal carcinomatosis...

  18. Fossilization of soft tissue in the laboratory.

    Science.gov (United States)

    Briggs, D E; Kear, A J

    1993-03-05

    Some of the most remarkable fossils preserve cellular details of soft tissues. In many of these, the tissues have been replaced by calcium phosphate. This process has been assumed to require elevated concentrations of phosphate in sediment pore waters. In decay experiments modern shrimps became partially mineralized in amorphous calcium phosphate, preserving cellular details of muscle tissue, particularly in a system closed to oxygen. The source for the formation of calcium phosphate was the shrimp itself. Mineralization, which was accompanied by a drop in pH, commenced within 2 weeks and increased in extent for at least 4 to 8 weeks. This mechanism halts the normal loss of detail of soft-tissue morphology before fossilization. Similar closed conditions would prevail where organisms are rapidly overgrown by microbial mats.

  19. Vascularization regenerative medicine and tissue engineering

    CERN Document Server

    Brey, Eric M

    2014-01-01

    A Complex and Growing Field The study of vascularization in tissue engineering and regenerative medicine (TERM) and its applications is an emerging field that could revolutionize medical approaches for organ and tissue replacement, reconstruction, and regeneration. Designed specifically for researchers in TERM fields, Vascularization: Regenerative Medicine and Tissue Engineering provides a broad overview of vascularization in TERM applications. This text summarizes research in several areas, and includes contributions from leading experts in the field. It defines the difficulties associated with multicellular processes in vascularization and cell-source issues. It presents advanced biomaterial design strategies for control of vascular network formation and in silico models designed to provide insight not possible in experimental systems. It also examines imaging methods that are critical to understanding vascularization in engineered tissues, and addresses vascularization issues within the context of specific...

  20. SEM investigation of heart tissue samples

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, R; Amoroso, M [Physics Department, University of the West Indies, St. Augustine, Trinidad and Tobago, West Indies (Trinidad and Tobago)

    2010-07-01

    We used the scanning electron microscope to examine the cardiac tissue of a cow (Bos taurus), a pig (Sus scrofa), and a human (Homo sapiens). 1mm{sup 3} blocks of left ventricular tissue were prepared for SEM scanning by fixing in 96% ethanol followed by critical point drying (cryofixation), then sputter-coating with gold. The typical ridged structure of the myofibrils was observed for all the species. In addition crystal like structures were found in one of the samples of the heart tissue of the pig. These structures were investigated further using an EDVAC x-ray analysis attachment to the SEM. Elemental x-ray analysis showed highest peaks occurred for gold, followed by carbon, oxygen, magnesium and potassium. As the samples were coated with gold for conductivity, this highest peak is expected. Much lower peaks at carbon, oxygen, magnesium and potassium suggest that a cystallized salt such as a carbonate was present in the tissue before sacrifice.

  1. Tissue disposition of bifenthrin in the rat

    Data.gov (United States)

    U.S. Environmental Protection Agency — Tissue disposition of bifenthrin in the rat and oral and intravenous administration. This dataset is associated with the following publication: Hughes , M., D. Ross...

  2. Cells for tissue engineering of cardiac valves.

    Science.gov (United States)

    Jana, Soumen; Tranquillo, Robert T; Lerman, Amir

    2016-10-01

    Heart valve tissue engineering is a promising alternative to prostheses for the replacement of diseased or damaged heart valves, because tissue-engineered valves have the ability to remodel, regenerate and grow. To engineer heart valves, cells are harvested, seeded onto or into a three-dimensional (3D) matrix platform to generate a tissue-engineered construct in vitro, and then implanted into a patient's body. Successful engineering of heart valves requires a thorough understanding of the different types of cells that can be used to obtain the essential phenotypes that are expressed in native heart valves. This article reviews different cell types that have been used in heart valve engineering, cell sources for harvesting, phenotypic expression in constructs and suitability in heart valve tissue engineering. Natural and synthetic biomaterials that have been applied as scaffold systems or cell-delivery platforms are discussed with each cell type. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  3. SEM investigation of heart tissue samples

    Science.gov (United States)

    Saunders, R.; Amoroso, M.

    2010-07-01

    We used the scanning electron microscope to examine the cardiac tissue of a cow (Bos taurus), a pig (Sus scrofa), and a human (Homo sapiens). 1mm3 blocks of left ventricular tissue were prepared for SEM scanning by fixing in 96% ethanol followed by critical point drying (cryofixation), then sputter-coating with gold. The typical ridged structure of the myofibrils was observed for all the species. In addition crystal like structures were found in one of the samples of the heart tissue of the pig. These structures were investigated further using an EDVAC x-ray analysis attachment to the SEM. Elemental x-ray analysis showed highest peaks occurred for gold, followed by carbon, oxygen, magnesium and potassium. As the samples were coated with gold for conductivity, this highest peak is expected. Much lower peaks at carbon, oxygen, magnesium and potassium suggest that a cystallized salt such as a carbonate was present in the tissue before sacrifice.

  4. Automated spectroscopic tissue classification in colorectal surgery

    NARCIS (Netherlands)

    Schols, R.M.; Alic, L.; Beets, G.L.; Breukink, S.O.; Wieringa, F.P.; Stassen, L.P.S.

    2015-01-01

    In colorectal surgery, detecting ureters and mesenteric arteries is of utmost importance to prevent iatrogenic injury and to facilitate intraoperative decision making. A tool enabling ureter- and artery-specific image enhancement within (and possibly through) surrounding adipose tissue would

  5. Incision for pleural tissue biopsy (image)

    Science.gov (United States)

    ... open pleural biopsy, a small piece of the pleural tissue is removed through a surgical incision in the chest. After the sample is obtained, a chest tube is placed and the incision is closed with ...

  6. Regenerating articular tissue by converging technologies

    NARCIS (Netherlands)

    Moroni, Lorenzo; Hamann, D.; Paoluzzi, Luca; Pieper, Jeroen; de Wijn, J.R.; van Blitterswijk, Clemens

    2008-01-01

    Scaffolds for osteochondral tissue engineering should provide mechanical stability, while offering specific signals for chondral and bone regeneration with a completely interconnected porous network for cell migration, attachment, and proliferation. Composites of polymers and ceramics are often

  7. Aetiological factors behind adipose tissue inflammation

    DEFF Research Database (Denmark)

    von Scholten, Bernt J; Andresen, Erik N; Sørensen, Thorkild I A

    2013-01-01

    Despite extensive research into the biological mechanisms behind obesity-related inflammation, knowledge of environmental and genetic factors triggering such mechanisms is limited. In the present narrative review we present potential determinants of adipose tissue inflammation and suggest ways...

  8. Processing laboratory of radio sterilized biological tissues

    International Nuclear Information System (INIS)

    Aguirre H, Paulina; Zarate S, Herman; Silva R, Samy; Hitschfeld, Mario

    2005-01-01

    The nuclear development applications have also reached those areas related to health. The risk of getting contagious illnesses through applying biological tissues has been one of the paramount worries to be solved since infectious illnesses might be provoked by virus, fungis or bacterias coming from donors or whether they have been introduced by means of intermediate stages before the use of these tissues. Therefore it has been concluded that the tissue allografts must be sterilized. The sterilization of medical products has been one of the main applications of the ionizing radiations and that it is why the International Organization of Atomic Energy began in the 70s promoting works related to the biological tissue sterilization and pharmaceutical products. The development of different tissue preservation methods has made possible the creation of tissue banks in different countries, to deal with long-term preservation. In our country, a project was launched in 1998, 'Establishment of a Tissue Bank in Latino america', this project was supported by the OIEA through the project INT/ 6/ 049, and was the starting of the actual Processing Laboratory of Radioesterilized Biological Tissues (LPTR), leaded by the Chilean Nuclear Energy Commission (CCHEN). This first organization is part of a number of entities compounding the Tissue Bank in Chile, organizations such as the Transplantation Promotion Corporation hospitals and the LPTR. The working system is carried out by means of the interaction between the hospitals and the laboratory. The medical professionals perform the procuring of tissues in the hospitals, then send them to the LPTR where they are processed and sterilized with ionizing radiation. The cycle ends up with the tissues return released to the hospitals, where they are used, and then the result information is sent to the LPTR as a form of feedback. Up to now, human skin has been processed (64 donors), amniotic membranes (35 donors) and pig skin (175 portions

  9. Tissue elasticity and the ageing elastic fibre

    OpenAIRE

    Sherratt, Michael J.

    2009-01-01

    The ability of elastic tissues to deform under physiological forces and to subsequently release stored energy to drive passive recoil is vital to the function of many dynamic tissues. Within vertebrates, elastic fibres allow arteries and lungs to expand and contract, thus controlling variations in blood pressure and returning the pulmonary system to a resting state. Elastic fibres are composite structures composed of a cross-linked elastin core and an outer layer of fibrillin microfibrils. Th...

  10. Glycogen storage in tissue-engineered cartilage.

    Science.gov (United States)

    Suits, Jocelyne M T; Khan, Aasma A; Waldman, Stephen D

    2008-08-01

    Recent focus in cartilage tissue engineering has been to develop functional tissue that can survive after implantation. One such determinant is the ability of the engineered tissue to be able to sustain its metabolic activity post-implantation. In vivo, chondrocytes contain stores of intracellular glycogen to support metabolism and it is unknown whether these cells can store glycogen during tissue growth in vitro. Thus, the purpose of this study was to determine the appropriate nutrient conditions to elicit glycogen storage in tissue-engineered cartilage. Isolated bovine articular chondrocytes were seeded in scaffold-free, 3D culture and grown under different nutrient conditions (glucose concentrations and media volumes) for 4 weeks. Intracellular glycogen storage, glucose utilization and extracellular matrix (ECM) accumulation of the engineered tissues were then evaluated. Glucose concentration (5-10 mM) and media volume (1-4 ml) had no apparent effect on cartilaginous tissue formation. However, glucose consumption by the cells increased in proportion to the volume of medium provided. Lactate production was similarly affected but in direct proportion to the glucose consumed, indicating a change in glucose utilization. Similarly, under elevated medium volume, engineered tissues stained positive for intracellular glycogen, which was also confirmed biochemically (1 ml, 1 +/- 2; 2 ml, 13 +/- 4; 4 ml, 13 +/- 3 microg/construct). The storage of intracellular glycogen in engineered cartilage can be elicited by culturing the constructs in elevated volumes of medium (>or=1 ml medium/million cells), which might help to ensure appropriate metabolic function after implantation. (c) 2008 John Wiley & Sons, Ltd.

  11. Introduction to tissue engineering applications and challenges

    CERN Document Server

    Birla, Ravi

    2014-01-01

    Covering a progressive medical field, Tissue Engineering describes the innovative process of regenerating human cells to restore or establish normal function in defective organs. As pioneering individuals look ahead to the possibility of generating entire organ systems, students may turn to this textbook for a comprehensive understanding and preparation for the future of regenerative medicine. This book explains chemical stimulations, the bioengineering of specific organs, and treatment plans for chronic diseases. It is a must-read for tissue engineering students and practitioners.

  12. Direct plasma interaction with living tissue

    Science.gov (United States)

    Fridman, Gregory

    For some time, plasma has been used in medicine to cauterize or cut tissue using heat and mechanical energy. In the recent decade, some researchers around the world have started to investigate how gas jets that pass through thermal plasma can be employed in medicine. This thesis presents the first investigation of biomedical uses of non-thermal plasma discharge which comes in direct contact with living tissue. It is demonstrated that the direct application of non-thermal plasma in air can cause rapid deactivation of bacteria on surfaces of tissues without causing any visible tissue damage. Medical need for such a device is discussed. Construction and operation of various types of non-thermal plasma power supplies and many types of treatment electrodes are presented as well. Application of this plasma to living organisms is shown to be safe from both the electrical perspective and from the biological perspective. Biological safety is revealed through a series of differential skin toxicity trials on human cadaver tissue, live hairless mouse skin tissue, live pig skin tissue, and finally in an open wound model on pigs. Direct non-thermal plasma in air is shown to deactivate bacteria about 100 times faster than indirect application using jets. A series of experiments reveal that this effectiveness is due to the ability of direct discharge to bring charges to tissue surfaces. It is demonstrated that neither ultraviolet (UV) radiation nor neutral active species such as hydroxyl radicals or ozone produced in plasma are responsible for the main effect on bacteria. Although much additional work remains on establishing detailed mechanism by which charges from plasma achieve this effect, the work carried out in this thesis clearly demonstrates that direct application of non-thermal plasma in air can be a very useful tool in medicine.

  13. Fetal tissue research and the misread compromise.

    Science.gov (United States)

    Kearney, W; Vawter, D E; Gervais, K G

    1991-01-01

    The bill to restore federal funding for human fetal tissue research has been passed by the House and awaits Senate approval. But it requires women who are willing to donate fetal tissue to certify that they did not have an abortion with the intent to donate. It further requires researchers to keep the certifications on file and available for government audit. Both requirements spell trouble.

  14. European quality system for tissue banking.

    Science.gov (United States)

    Manyalich, M; Navarro, A; Koller, J; Loty, B; de Guerra, A; Cornu, O; Vabels, G; Fornasari, P M; Costa, A N; Siska, I; Hirn, M; Franz, N; Miranda, B; Kaminski, A; Uhrynowska, I; Van Baare, J; Trias, E; Fernández, C; de By, T; Poniatowski, S; Carbonell, R

    2009-01-01

    The aims of this project were to analyze the factors that influence quality and safety of tissues for transplantation and to develop the method to ensure standards of quality and safety in relation to tissue banking as demanded by European Directive 2004/23/EC and its technical annexes. It is organized in 4 Working Groups, the objectives of each one being focused in a specific area. The Guide of Recommendations for Tissue Banking is structured into 4 parts: (1) quality systems that apply to tissue banking and general quality system requirements, (2) regulatory framework in Europe, (3) standards available, and (4) recommendations of the fundamental quality and safety keypoints. This Working Group handled design of a multinational musculoskeletal tissue registry prototype. This Working Group handled design and validation of a specialized training model structured into online and face-to-face courses. The model was improved with suggestions from students, and 100% certification was obtained. The Guide for Auditing Tissue Establishments provides guidance for auditors, a self-assessment questionnaire, and an audit report form. The effectiveness and sustainability of the outputs were assessed. Both guides are useful for experienced tissue establishments and auditors and also for professionals that are starting in the field. The registry prototype proves it is possible to exchange tissues between establishments throughout Europe. The training model has been effective in educating staff and means having professionals with excellent expertise. Member states could adapt/adopt it. The guides should be updated periodically and perhaps a European organization should take responsibility for this and even create a body of auditors.

  15. CO2 laser milling of hard tissue

    Science.gov (United States)

    Werner, Martin; Ivanenko, Mikhail; Harbecke, Daniela; Klasing, Manfred; Steigerwald, Hendrik; Hering, Peter

    2007-02-01

    Drilling of bone and tooth tissue belongs to recurrent medical procedures (screw- and pin-bores, bores for implant inserting, trepanation etc.). Small round bores can be in general quickly produced with mechanical drills. Problems arise however by angled drilling, by the necessity to fulfill the drilling without damaging of sensitive soft tissue beneath the bone, or by the attempt to mill precisely noncircular small cavities. We present investigations on laser hard tissue "milling", which can be advantageous for solving these problems. The "milling" is done with a CO2 laser (10.6 μm) with pulse duration of 50 - 100 μs, combined with a PC-controlled galvanic beam scanner and with a fine water-spray, which helps to avoid thermal side-effects. The damaging of underlying soft tissue can be prevented through control of the optical or acoustical ablation signal. The ablation of hard tissue is accompanied with a strong glowing, which is absent during the laser beam action on soft tissue. The acoustic signals from the diverse tissue types exhibit distinct differences in the spectral composition. Also computer image analysis could be a useful tool to control the operation. Laser "milling" of noncircular cavities with 1 - 4 mm width and about 10 mm depth is particularly interesting for dental implantology. In ex-vivo investigations we found conditions for fast laser "milling" of the cavities without thermal damage and with minimal tapering. It included exploration of different filling patterns (concentric rings, crosshatch, parallel lines and their combinations), definition of maximal pulse duration, repetition rate and laser power, optimal position of the spray. The optimized results give evidences for the applicability of the CO2 laser for biologically tolerable "milling" of deep cavities in the hard tissue.

  16. Vitamine E et physiologie du tissu adipeux

    Directory of Open Access Journals (Sweden)

    Landrier Jean-François

    2011-03-01

    Full Text Available Vitamin E constitutes a family of eight molecules well-known for its antioxidant properties and its essentiality in fertility. Its ability to regulate gene expression is more and more described and could be a major actor of its biological activity. Adipose tissue which is the main store site of vitamin E within the body is also subjected to the regulatory effect of vitamin E. These regulations could strongly impact adipose tissue physiology.

  17. Pediatric rhabdomyosarcomas and nonrhabdomyosarcoma soft tissue sarcoma

    OpenAIRE

    Agarwala Sandeep

    2006-01-01

    Tumors arising from the soft tissues are uncommon in children, accounting for about 6% of all childhood malignancies. More than half (53%) of these originate from the striated muscles and are called rhabdomyosarcomas (RMS) the remaining are nonrhabdomyosarcoma soft tissue sarcomas (NRSTS). Almost two-thirds of RMS cases are diagnosed in children < 6 years of age. They can arise at varied locations like the head and neck region, genitourinary tract, extremities, trunk and retrope...

  18. Tissue culture in forestry and agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Henke, R.R.; Hughes, K.W.; Constantin, M.J.; Hollaender, A. (eds.)

    1985-01-01

    This symposium aims to examine the current state-of-the-art in tissue culture technology and to relate this state of technology to practical, applied, and commercial interests. Thus the focus is on embryogenesis in culture: how to recognize it, factors which affect embryogenesis, use of embryogenic systems, etc.; and variability from culture. A special session on woody species again emphasized somatic embryogenesis as a means of rapid propagation. This volume emphasizes tissue culture of forest trees.

  19. Beta adrenergic receptors in human cavernous tissue

    Energy Technology Data Exchange (ETDEWEB)

    Dhabuwala, C.B.; Ramakrishna, C.V.; Anderson, G.F.

    1985-04-01

    Beta adrenergic receptor binding was performed with /sup 125/I iodocyanopindolol on human cavernous tissue membrane fractions from normal tissue and transsexual procedures obtained postoperatively, as well as from postmortem sources. Isotherm binding studies on normal fresh tissues indicated that the receptor density was 9.1 fmoles/mg. with a KD of 23 pM. Tissue stored at room temperature for 4 to 6 hours, then at 4C in saline solution for 19 to 20 hours before freezing showed no significant changes in receptor density or affinity, and provided evidence for the stability of postmortem tissue obtained within the same time period. Beta receptor density of 2 cavernous preparations from transsexual procedures was not significantly different from normal control tissues, and showed that high concentrations of estrogen received by these patients had no effect on beta adrenergic receptor density. Displacement of /sup 125/iodocyanopindolol by 5 beta adrenergic agents demonstrated that 1-propranolol had the greatest affinity followed by ICI 118,551, zinterol, metoprolol and practolol. When the results of these displacement studies were subjected to Scatfit, non- linear regression line analysis, a single binding site was described. Based on the relative potency of the selective beta adrenergic agents it appears that these receptors were of the beta 2 subtype.

  20. Space Radiation Program Element Tissue Sharing Forum

    Science.gov (United States)

    Wu, H.; Mayeaux, B M.; Huff, J. L.; Simonsen, L. C.

    2016-01-01

    Over the years, a large number of animal experiments have been conducted at the NASA Space Radiation Laboratory and other facilities under the support of the NASA Space Radiation Program Element (SRPE). Studies using rodents and other animal species to address the space radiation risks will remain a significant portion of the research portfolio of the Element. In order to maximize scientific return of the animal studies, the SRPE has recently released the Space Radiation Tissue Sharing Forum. The Forum provides access to an inventory of investigator-stored tissue samples and enables both NASA SRPE members and NASA-funded investigators to exchange information regarding stored and future radiobiological tissues available for sharing. Registered users may review online data of available tissues, inquire about tissues posted, or request tissues for an upcoming study using an online form. Investigators who have upcoming sacrifices are also encouraged to post the availability of samples using the discussion forum. A brief demo of the forum will be given during the presentation

  1. Sterilization of biological tissues with ionizing radiation

    International Nuclear Information System (INIS)

    Reyes F, M.L.; Martinez P, M.E.; Luna Z, D.

    1997-01-01

    On June 1994, the National Institute of Nuclear Research (ININ) and the South Central Hospital for High Specialty of PEMEX (HCSAE) began a joint work with the finality to obtain radio sterilized amniotic membranes for to be used as cover (biological bandage) in burnt patients. Subsequently the Chemistry Faculty of UNAM and the National Institute of Cardiology began to collaborate this last with interest on cardiac valves for graft. Starting from 1997, the International Atomic Energy Agency (IAEA) supports this project (MEX/7/008) whose main objective is to set up the basis to establish in Mexico a Radio sterilized Tissue Bank (amniotic membranes, skin, bones, tendons, cardiac valves, etc.) to be used with therapeutic purposes (grafts). The IAEA support has consisted in the equipment acquisition which is fundamental for the Tissue Bank performance such as an experimental irradiator, laminar flow bell, lyophilizer, vacuum sealer and special knives for tissues. Also visits to Mexico of experts have been authorized with the aim of advising to the personnel which participate in the project and scientific visits of this personnel to another tissue banks (Sri Lanka and Argentine). The establishment in Mexico of a Tissue bank will be a great benefit because it will have availability of distinct tissues for grafts and it will reduce the synthetic materials importation which is very expensive. (Author)

  2. Analysis of lung tissue using ion beams

    International Nuclear Information System (INIS)

    Alvarez, J.L.; Barrera, R.; Miranda, J.

    2002-01-01

    In this work a comparative study is presented of the contents of metals in lung tissue from healthy patients and with lung cancer, by means of two analytical techniques: Particle Induced X-ray Emission (PIXE) and Rutherford Backscattering Spectrometry (RBS). The samples of cancerous tissue were taken from 26 autopsies made to individuals died in the National Institute of Respiratory Disease (INER), 22 of cancer and 4 of other non-cancer biopsies. When analyzing the entirety of the samples, in the cancerous tissues, there were increments in the concentrations of S (4%), K (635%), Co (85%) and Cu (13%). Likewise, there were deficiencies in the concentrations of Cl (59%), Ca (6%), Fe (26%) and Zn (7%). Only in the cancerous tissues there were appearances of P, Ca, Ti, V, Cr, Mn, Ni, Br and Sr. The tissue samples were classified according to cancer types (adenocarcinomas, epidermoides and of small cell carcinoma), personal habits (smokers and alcoholic), genetic predisposition and residence place. There was a remarkable decrease in the concentration of Ca and a marked increment in the Cu in the epidermoide tissue samples with regard to those of adenocarcinoma or of small cells cancer. Also, decrements were detected in K and increments of Fe, Co and Cu in the sample belonging to people that resided in Mexico City with regard to those that resided in the State of Mexico

  3. Chitosan adhesive for laser tissue repair

    Science.gov (United States)

    Lauto, A.; Stoodley, M.; Avolio, A.; Foster, L. J. R.

    2006-02-01

    Background. Laser tissue repair usually relies on haemoderivate solders, based on serum albumin. These solders have intrinsic limitations that impair their widespread use, such as limited repair strength, high solubility, brittleness and viral transmission. Furthermore, the solder activation temperature (65-70 °C) can induce significant damage to tissue. In this study, a new laser-activated biomaterial for tissue repair was developed and tested in vitro and in vivo to overcome some of the shortcomings of traditional solders. Materials and Methods. Flexible and insoluble strips of chitosan adhesive (surface area ~34 mm2, thickness ~20 μm) were developed and bonded on sheep intestine with a laser fluence and irradiance of 52 +/- 2 J/cm2 and ~15 W/cm2 respectively. The temperature between tissue and adhesive was measured using small thermocouples. The strength of repaired tissue was tested by a calibrated tensiometer. The adhesive was also bonded in vivo to the sciatic nerve of rats to assess the thermal damage induced by the laser (fluence = 65 +/- 11 J/cm2, irradiance = 15 W/cm2) four days post-operatively. Results. Chitosan adhesives successfully repaired intestine tissue, achieving a repair strength of 0.50 +/- 0.15 N (shear stress = 14.7 +/- 4.7 KPa, n=30) at a temperature of 60-65 °C. The laser caused demyelination of axons at the operated site; nevertheless, the myelinated axons retained their normal morphology proximally and distally.

  4. Dynamic compressive response of bovine liver tissues.

    Science.gov (United States)

    Pervin, Farhana; Chen, Weinong W; Weerasooriya, Tusit

    2011-01-01

    This study aims to experimentally determine the strain rate effects on the compressive stress-strain behavior of bovine liver tissues. Fresh liver tissues were used to make specimens for mechanical loading. Experiments at quasi-static strain rates were conducted at 0.01 and 0.1 s(-1). Intermediate-rate experiments were performed at 1, 10, and 100 s(-1). High strain rate (1000, 2000, and 3000 s(-1)) experiments were conducted using a Kolsky bar modified for soft material characterization. A hollow transmission bar with semi-conductor strain gages was used to sense the weak forces from the soft specimens. Quartz-crystal force transducers were used to monitor valid testing conditions on the tissue specimens. The experiment results show that the compressive stress-strain response of the liver tissue is non-linear and highly rate-sensitive, especially when the strain rate is in the Kolsky bar range. The tissue stiffens significantly with increasing strain rate. The responses from liver tissues along and perpendicular to the liver surface were consistent, indicating isotropic behavior. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Designing Smart Biomaterials for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Ferdous Khan

    2017-12-01

    Full Text Available The engineering of human tissues to cure diseases is an interdisciplinary and a very attractive field of research both in academia and the biotechnology industrial sector. Three-dimensional (3D biomaterial scaffolds can play a critical role in the development of new tissue morphogenesis via interacting with human cells. Although simple polymeric biomaterials can provide mechanical and physical properties required for tissue development, insufficient biomimetic property and lack of interactions with human progenitor cells remain problematic for the promotion of functional tissue formation. Therefore, the developments of advanced functional biomaterials that respond to stimulus could be the next choice to generate smart 3D biomimetic scaffolds, actively interacting with human stem cells and progenitors along with structural integrity to form functional tissue within a short period. To date, smart biomaterials are designed to interact with biological systems for a wide range of biomedical applications, from the delivery of bioactive molecules and cell adhesion mediators to cellular functioning for the engineering of functional tissues to treat diseases.

  6. Photochemical tissue bonding with chitosan adhesive films

    Directory of Open Access Journals (Sweden)

    Piller Sabine C

    2010-09-01

    Full Text Available Abstract Background Photochemical tissue bonding (PTB is a promising sutureless technique for tissue repair. PTB is often achieved by applying a solution of rose bengal (RB between two tissue edges, which are irradiated by a green laser to crosslink collagen fibers with minimal heat production. In this study, RB has been incorporated in chitosan films to create a novel tissue adhesive that is laser-activated. Methods Adhesive films, based on chitosan and containing ~0.1 wt% RB were manufactured and bonded to calf intestine by a solid state laser (λ = 532 nm, Fluence~110 J/cm2, spot size~0.5 cm. A single-column tensiometer, interfaced with a personal computer, tested the bonding strength. K-type thermocouples recorded the temperature (T at the adhesive-tissue interface during laser irradiation. Human fibroblasts were also seeded on the adhesive and cultured for 48 hours to assess cell growth. Results The RB-chitosan adhesive bonded firmly to the intestine with adhesion strength of 15 ± 2 kPa, (n = 31. The adhesion strength dropped to 0.5 ± 0.1 (n = 8 kPa when the laser was not applied to the adhesive. The average temperature of the adhesive increased from 26°C to 32°C during laser exposure. Fibroblasts grew confluent on the adhesive without morphological changes. Conclusion A new biocompatible chitosan adhesive has been developed that bonds photochemically to tissue with minimal temperature increase.

  7. Influencing Factors of Thermogenic Adipose Tissue Activity.

    Science.gov (United States)

    Zhang, Guoqing; Sun, Qinghua; Liu, Cuiqing

    2016-01-01

    Obesity is an escalating public health challenge and contributes tremendously to the disease burden globally. New therapeutic strategies are required to alleviate the health impact of obesity-related metabolic dysfunction. Brown adipose tissue (BAT) is specialized for dissipating chemical energy for thermogenesis as a defense against cold environment. Intriguingly, the brown-fat like adipocytes that dispersed throughout white adipose tissue (WAT) in rodents and humans, called "brite" or "beige" adipocytes, share similar thermogenic characteristics to brown adipocytes. Recently, researchers have focused on cognition of these thermogenic adipose tissues. Some factors have been identified to regulate the development and function of thermogenic adipose tissues. Cold exposure, pharmacological conditions, and lifestyle can enhance non-shivering thermogenesis and metabolism via some mechanisms. However, environmental pollutants, such as ambient fine particulates and ozone, may impair the function of these thermogenic adipose tissues and thereby induce metabolic dysfunction. In this review, the origin, function and influencing factors of thermogenic adipose tissues were summarized and it will provide insights into identifying new therapeutic strategies for the treatment of obesity and obesity-related diseases.

  8. The Facial Adipose Tissue: A Revision.

    Science.gov (United States)

    Kruglikov, Ilja; Trujillo, Oscar; Kristen, Quick; Isac, Kerelos; Zorko, Julia; Fam, Maria; Okonkwo, Kasie; Mian, Asima; Thanh, Hyunh; Koban, Konstantin; Sclafani, Anthony P; Steinke, Hanno; Cotofana, Sebastian

    2016-12-01

    Recent advantages in the anatomical understanding of the face have turned the focus toward the subcutaneous and deep facial fat compartments. During facial aging, these fat-filled compartments undergo substantial changes along with other structures in the face. Soft tissue filler and fat grafting are valid methods to fight the signs of facial aging, but little is known about their precise effect on the facial fat. This narrative review summarizes the current knowledge about the facial fat compartments in terms of anatomical location, histologic appearance, immune-histochemical characteristics, cellular interactions, and therapeutic options. Three different types of facial adipose tissue can be identified, which are located either superficially (dermal white adipose tissue) or deep (subcutaneous white adipose tissue): fibrous (perioral locations), structural (major parts of the midface), and deposit (buccal fat pad and deep temporal fat pad). These various fat types differ in the size of the adipocytes and the collagenous composition of their extracellular matrix and thus in their mechanical properties. Minimal invasive (e.g., soft tissue fillers or fat grafting) and surgical interventions aiming to restore the youthful face have to account for the different fat properties in various facial areas. However, little is known about the macro- and microscopic characteristics of the facial fat tissue in different compartments and future studies are needed to reveal new insights to better understand the process of aging and how to fight its signs best. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  9. Monitoring soft tissue coagulation by optical spectroscopy

    Science.gov (United States)

    Lihachev, A.; Lihacova, I.; Heinrichs, H.; Spigulis, J.; Trebst, T.; Wehner, M.

    2017-12-01

    Laser tissue welding (LTW) or laser tissue soldering (LTS) is investigated since many years for treatment of incisions, wound closure and anastomosis of vessels [1, 2]. Depending on the process, a certain temperature in the range between 65 °C to 85 °C must be reached and held for a few seconds. Care has to be taken not to overheat the tissue, otherwise necrosis or tissue carbonization may occur and will impair wound healing. Usually the temperature is monitored during the process to control the laser power [3]. This requires either bulky equipment or expensive and fragile infrared fibers to feed the temperature signal to an infrared detector. Alternatively, changes in tissue morphology can be directly observed by analysis of spectral reflectance. We investigate spectral changes in the range between 400 nm to 900 nm wavelength. Characteristic spectral changes occur when the temperature of tissue samples increase above 70 °C which is a typical setpoint value for temperature control of coagulation. We conclude that simple spectroscopy in the visible range can provide valuable information during LTS and LTW and probably replace the delicate measurement of temperature. A major advantage is that optical measurements can be performed using standard optical fibers and can be easily integrated into a surgical tool.

  10. Clinical relevance of fascial tissue and dysfunctions.

    Science.gov (United States)

    Klingler, W; Velders, M; Hoppe, K; Pedro, M; Schleip, R

    2014-01-01

    Fascia is composed of collagenous connective tissue surrounding and interpenetrating skeletal muscle, joints, organs, nerves, and vascular beds. Fascial tissue forms a whole-body, continuous three-dimensional viscoelastic matrix of structural support. The classical concept of its mere passive role in force transmission has recently been disproven. Fascial tissue contains contractile elements enabling a modulating role in force generation and also mechanosensory fine-tuning. This hypothesis is supported by in vitro studies demonstrating an autonomous contraction of human lumbar fascia and a pharmacological induction of temporary contraction in rat fascial tissue. The ability of spontaneous regulation of fascial stiffness over a time period ranging from minutes to hours contributes more actively to musculoskeletal dynamics. Imbalance of this regulatory mechanism results in increased or decreased myofascial tonus, or diminished neuromuscular coordination, which are key contributors to the pathomechanisms of several musculoskeletal pathologies and pain syndromes. Here, we summarize anatomical and biomechanical properties of fascial tissue with a special focus on fascial dysfunctions and resulting clinical manifestations. Finally, we discuss current and future potential treatment options that can influence clinical manifestations of pain syndromes associated with fascial tissues.

  11. 3D bioprinting of tissues and organs.

    Science.gov (United States)

    Murphy, Sean V; Atala, Anthony

    2014-08-01

    Additive manufacturing, otherwise known as three-dimensional (3D) printing, is driving major innovations in many areas, such as engineering, manufacturing, art, education and medicine. Recent advances have enabled 3D printing of biocompatible materials, cells and supporting components into complex 3D functional living tissues. 3D bioprinting is being applied to regenerative medicine to address the need for tissues and organs suitable for transplantation. Compared with non-biological printing, 3D bioprinting involves additional complexities, such as the choice of materials, cell types, growth and differentiation factors, and technical challenges related to the sensitivities of living cells and the construction of tissues. Addressing these complexities requires the integration of technologies from the fields of engineering, biomaterials science, cell biology, physics and medicine. 3D bioprinting has already been used for the generation and transplantation of several tissues, including multilayered skin, bone, vascular grafts, tracheal splints, heart tissue and cartilaginous structures. Other applications include developing high-throughput 3D-bioprinted tissue models for research, drug discovery and toxicology.

  12. Analysis of Lung Tissue Using Ion Beams

    Science.gov (United States)

    Alvarez, J. L.; Barrera, R.; Miranda, J.

    2002-08-01

    In this work a comparative study is presented of the contents of metals in lung tissue from healthy patients and with lung cancer, by means of two analytical techniques: Particle Induced X-ray Emission (PIXE) and Rutherford Backscattering Spectrometry (RBS). The samples of cancerous tissue were taken from 26 autopsies made to individuals died in the National Institute of Respiratory Disease (INER), 22 of cancer and 4 of other non-cancer biopsies. When analyzing the entirety of the samples, in the cancerous tissues, there were increments in the concentrations of S (4%), K (635%), Co (85%) and Cu (13%). Likewise, there were deficiencies in the concentrations of Cl (59%), Ca (6%), Fe (26%) and Zn (7%). Only in the cancerous tissues there were appearances of P, Ca, Ti, V, Cr, Mn, Ni, Br and Sr. The tissue samples were classified according to cancer types (adenocarcinomas, epidermoides and of small cell carcinoma), personal habits (smokers and alcoholic), genetic predisposition and residence place. There was a remarkable decrease in the concentration of Ca and a marked increment in the Cu in the epidermoide tissue samples with regard to those of adenocarcinoma or of small cells cancer. Also, decrements were detected in K and increments of Fe, Co and Cu in the sample belonging to people that resided in Mexico City with regard to those that resided in the State of Mexico.

  13. Stem cells in bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Jeong Min [Department of Preventive and Social Dentistry and Institute of Oral Biology, College of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Kim, Byung-Chul; Park, Jae-Hong; Kwon, Il Keun; Hwang, Yu-Shik [Department of Maxillofacial Biomedical Engineering and Institute of Oral Biology, College of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Mantalaris, Anathathios, E-mail: yshwang@khu.ac.k [Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom)

    2010-12-15

    Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have received extensive attention in the field of bone tissue engineering due to their distinct biological capability to differentiate into osteogenic lineages. The application of these stem cells to bone tissue engineering requires inducing in vitro differentiation of these cells into bone forming cells, osteoblasts. For this purpose, efficient in vitro differentiation towards osteogenic lineage requires the development of well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source for application to bone tissue engineering therapies. This review provides a critical examination of the various experimental strategies that could be used to direct the differentiation of ESC, BM-MSC, UCB-MSC, ADSC, MDSC and DPSC towards osteogenic lineages and their potential applications in tissue engineering, particularly in the regeneration of bone. (topical review)

  14. Bioactive polymeric scaffolds for tissue engineering

    Science.gov (United States)

    Stratton, Scott; Shelke, Namdev B.; Hoshino, Kazunori; Rudraiah, Swetha; Kumbar, Sangamesh G.

    2016-01-01

    A variety of engineered scaffolds have been created for tissue engineering using polymers, ceramics and their composites. Biomimicry has been adopted for majority of the three-dimensional (3D) scaffold design both in terms of physicochemical properties, as well as bioactivity for superior tissue regeneration. Scaffolds fabricated via salt leaching, particle sintering, hydrogels and lithography have been successful in promoting cell growth in vitro and tissue regeneration in vivo. Scaffold systems derived from decellularization of whole organs or tissues has been popular due to their assured biocompatibility and bioactivity. Traditional scaffold fabrication techniques often failed to create intricate structures with greater resolution, not reproducible and involved multiple steps. The 3D printing technology overcome several limitations of the traditional techniques and made it easier to adopt several thermoplastics and hydrogels to create micro-nanostructured scaffolds and devices for tissue engineering and drug delivery. This review highlights scaffold fabrication methodologies with a focus on optimizing scaffold performance through the matrix pores, bioactivity and degradation rate to enable tissue regeneration. Review highlights few examples of bioactive scaffold mediated nerve, muscle, tendon/ligament and bone regeneration. Regardless of the efforts required for optimization, a shift in 3D scaffold uses from the laboratory into everyday life is expected in the near future as some of the methods discussed in this review become more streamlined. PMID:28653043

  15. A Hybrid Tissue-Engineered Heart Valve.

    Science.gov (United States)

    Alavi, S Hamed; Kheradvar, Arash

    2015-06-01

    This study describes the efforts to develop and test the first hybrid tissue-engineered heart valve whose leaflets are composed of an extra-thin superelastic Nitinol mesh tightly enclosed by uniform tissue layers composed of multiple cell types. The trileaflet Nitinol mesh scaffolds underwent three-dimensional cell culture with smooth muscle and fibroblast/myofibroblast cells enclosing the mesh, which were finally covered by an endothelial cell layer. Quantitative and qualitative assays were performed to analyze the microstructure of the tissues. A tissue composition almost similar to that of natural heart valve leaflets was observed. The function of the valves and their Nitinol scaffolds were tested in a heart flow simulator that confirmed the trileaflet valves open and close robustly under physiologic flow conditions with an effective orifice area of 75%. The tissue-metal attachment of the leaflets once exposed to physiologic flow rates was tested and approved. Our preliminary results indicate that the novel hybrid approach with nondegradable scaffold for engineering heart valves is viable and may address the issues associated with current tissue-engineered valves developed with degradable scaffolds. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Progress in the processing of radioesterilized tissue

    International Nuclear Information System (INIS)

    Zarate S, H; Espinoza B, J; Ribbeck N, J; Vargas Q, M; Gutierrez D, K

    2003-01-01

    Since 1996, the Chilean Nuclear Energy Commission has been carrying out work to implement the first Radiosterilized Tissue Processing Laboratory (RTPL) in Chile, in order to introduce the use of sterilized biological tissue for clinical application. The International Atomic Energy Agency (IAEA) has provided collaboration and technical assistance for this work. The processing of biological tissues has been done in conjunction with physicians from different state hospital centers, mostly in the Metropolitan Region. Among the tissues primarily processed are allografts such as frozen human skin at - 80 o C, freeze-dried human bone and amniotic membrane. We have also been working with xenograft developments such as freeze-dried pig skin and demineralized ground cow bone. All these tissues are sterilized by means of gamma radiation, in order to obtain a sterility assurance level (SAL) of 10 -6 . This laboratory has already completed various stages, from the beginning when it was only just an idea up to the production stage where a large quantity of processed tissues have been delivered to physicians of different specialties, resulting in a contribution to medical science as well as to the treatment quality of a great many patients. The preliminary results and the opinions of those physicians who have used the processed products from our laboratory have encouraged us to continue developing new products, thus enlarging the scope of application (author)

  17. The materials used in bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Tereshchenko, V. P., E-mail: tervp@ngs.ru; Kirilova, I. A.; Sadovoy, M. A.; Larionov, P. M. [Novosibirsk Research Institute of Traumatology and Orthopedics n.a. Ya.L. Tsivyan, Novosibirsk (Russian Federation)

    2015-11-17

    Bone tissue engineering looking for an alternative solution to the problem of skeletal injuries. The method is based on the creation of tissue engineered bone tissue equivalent with stem cells, osteogenic factors, and scaffolds - the carriers of these cells. For production of tissue engineered bone equivalent is advisable to create scaffolds similar in composition to natural extracellular matrix of the bone. This will provide optimal conditions for the cells, and produce favorable physico-mechanical properties of the final construction. This review article gives an analysis of the most promising materials for the manufacture of cell scaffolds. Biodegradable synthetic polymers are the basis for the scaffold, but it alone cannot provide adequate physical and mechanical properties of the construction, and favorable conditions for the cells. Addition of natural polymers improves the strength characteristics and bioactivity of constructions. Of the inorganic compounds, to create cell scaffolds the most widely used calcium phosphates, which give the structure adequate stiffness and significantly increase its osteoinductive capacity. Signaling molecules do not affect the physico-mechanical properties of the scaffold, but beneficial effect is on the processes of adhesion, proliferation and differentiation of cells. Biodegradation of the materials will help to fulfill the main task of bone tissue engineering - the ability to replace synthetic construct by natural tissues that will restore the original anatomical integrity of the bone.

  18. Bone Tissue Engineering: Recent Advances and Challenges

    Science.gov (United States)

    Amini, Ami R.; Laurencin, Cato T.; Nukavarapu, Syam P.

    2013-01-01

    The worldwide incidence of bone disorders and conditions has trended steeply upward and is expected to double by 2020, especially in populations where aging is coupled with increased obesity and poor physical activity. Engineered bone tissue has been viewed as a potential alternative to the conventional use of bone grafts, due to their limitless supply and no disease transmission. However, bone tissue engineering practices have not proceeded to clinical practice due to several limitations or challenges. Bone tissue engineering aims to induce new functional bone regeneration via the synergistic combination of biomaterials, cells, and factor therapy. In this review, we discuss the fundamentals of bone tissue engineering, highlighting the current state of this field. Further, we review the recent advances of biomaterial and cell-based research, as well as approaches used to enhance bone regeneration. Specifically, we discuss widely investigated biomaterial scaffolds, micro- and nano-structural properties of these scaffolds, and the incorporation of biomimetic properties and/or growth factors. In addition, we examine various cellular approaches, including the use of mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), adult stem cells, induced pluripotent stem cells (iPSCs), and platelet-rich plasma (PRP), and their clinical application strengths and limitations. We conclude by overviewing the challenges that face the bone tissue engineering field, such as the lack of sufficient vascularization at the defect site, and the research aimed at functional bone tissue engineering. These challenges will drive future research in the field. PMID:23339648

  19. The materials used in bone tissue engineering

    Science.gov (United States)

    Tereshchenko, V. P.; Kirilova, I. A.; Sadovoy, M. A.; Larionov, P. M.

    2015-11-01

    Bone tissue engineering looking for an alternative solution to the problem of skeletal injuries. The method is based on the creation of tissue engineered bone tissue equivalent with stem cells, osteogenic factors, and scaffolds - the carriers of these cells. For production of tissue engineered bone equivalent is advisable to create scaffolds similar in composition to natural extracellular matrix of the bone. This will provide optimal conditions for the cells, and produce favorable physico-mechanical properties of the final construction. This review article gives an analysis of the most promising materials for the manufacture of cell scaffolds. Biodegradable synthetic polymers are the basis for the scaffold, but it alone cannot provide adequate physical and mechanical properties of the construction, and favorable conditions for the cells. Addition of natural polymers improves the strength characteristics and bioactivity of constructions. Of the inorganic compounds, to create cell scaffolds the most widely used calcium phosphates, which give the structure adequate stiffness and significantly increase its osteoinductive capacity. Signaling molecules do not affect the physico-mechanical properties of the scaffold, but beneficial effect is on the processes of adhesion, proliferation and differentiation of cells. Biodegradation of the materials will help to fulfill the main task of bone tissue engineering - the ability to replace synthetic construct by natural tissues that will restore the original anatomical integrity of the bone.

  20. Bioactive polymeric scaffolds for tissue engineering

    Directory of Open Access Journals (Sweden)

    Scott Stratton

    2016-12-01

    Full Text Available A variety of engineered scaffolds have been created for tissue engineering using polymers, ceramics and their composites. Biomimicry has been adopted for majority of the three-dimensional (3D scaffold design both in terms of physicochemical properties, as well as bioactivity for superior tissue regeneration. Scaffolds fabricated via salt leaching, particle sintering, hydrogels and lithography have been successful in promoting cell growth in vitro and tissue regeneration in vivo. Scaffold systems derived from decellularization of whole organs or tissues has been popular due to their assured biocompatibility and bioactivity. Traditional scaffold fabrication techniques often failed to create intricate structures with greater resolution, not reproducible and involved multiple steps. The 3D printing technology overcome several limitations of the traditional techniques and made it easier to adopt several thermoplastics and hydrogels to create micro-nanostructured scaffolds and devices for tissue engineering and drug delivery. This review highlights scaffold fabrication methodologies with a focus on optimizing scaffold performance through the matrix pores, bioactivity and degradation rate to enable tissue regeneration. Review highlights few examples of bioactive scaffold mediated nerve, muscle, tendon/ligament and bone regeneration. Regardless of the efforts required for optimization, a shift in 3D scaffold uses from the laboratory into everyday life is expected in the near future as some of the methods discussed in this review become more streamlined.

  1. Stem cells in bone tissue engineering

    International Nuclear Information System (INIS)

    Seong, Jeong Min; Kim, Byung-Chul; Park, Jae-Hong; Kwon, Il Keun; Hwang, Yu-Shik; Mantalaris, Anathathios

    2010-01-01

    Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have received extensive attention in the field of bone tissue engineering due to their distinct biological capability to differentiate into osteogenic lineages. The application of these stem cells to bone tissue engineering requires inducing in vitro differentiation of these cells into bone forming cells, osteoblasts. For this purpose, efficient in vitro differentiation towards osteogenic lineage requires the development of well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source for application to bone tissue engineering therapies. This review provides a critical examination of the various experimental strategies that could be used to direct the differentiation of ESC, BM-MSC, UCB-MSC, ADSC, MDSC and DPSC towards osteogenic lineages and their potential applications in tissue engineering, particularly in the regeneration of bone. (topical review)

  2. Pulp and periodontal tissue repair - regeneration or tissue metaplasia after dental trauma. A review

    DEFF Research Database (Denmark)

    Andreasen, Jens O

    2012-01-01

    Healing subsequent to dental trauma is known to be very complex, a result explained by the variability of the types of dental trauma (six luxations, nine fracture types, and their combinations). On top of that, at least 16 different cellular systems get involved in more severe trauma types each...... of them with a different potential for healing with repair, i.e. (re-establishment of tissue continuity without functional restitution) and regeneration (where the injured or lost tissue is replaced with new tissue with identical tissue anatomy and function) and finally metaplasia (where a new type...... of tissue replaces the injured). In this study, a review is given of the impact of trauma to various dental tissues such as alveolar bone, periodontal ligament, cementum, Hertvigs epithelial root sheath, and the pulp....

  3. Bioengineered silk scaffolds in 3D tissue modeling with focus on mammary tissues.

    Science.gov (United States)

    Maghdouri-White, Yas; Bowlin, Gary L; Lemmon, Christopher A; Dréau, Didier

    2016-02-01

    In vitro generation of three-dimensional (3D) biological tissues and organ-like structures is a promising strategy to study and closely model complex aspects of the molecular, cellular, and physiological interactions of tissue. In particular, in vitro 3D tissue modeling holds promises to further our understanding of breast development. Indeed, biologically relevant 3D structures that combine mammary cells and engineered matrices have improved our knowledge of mammary tissue growth, organization, and differentiation. Several polymeric biomaterials have been used as scaffolds to engineer 3D mammary tissues. Among those, silk fibroin-based biomaterials have many biologically relevant properties and have been successfully used in multiple medical applications. Here, we review the recent advances in engineered scaffolds with an emphasis on breast-like tissue generation and the benefits of modified silk-based scaffolds. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Management of peri-implant soft tissue defect with connective tissue graft - A case report

    Directory of Open Access Journals (Sweden)

    Mohinder Panwar

    2017-01-01

    Full Text Available The use of dental implants to replace missing and nonrestorable teeth has increased significantly in the past two decades. The health of peri-implant tissues plays an important role in the long-term success of dental implants. Soft tissue dehiscence around dental implants has frequently been reported which may lead to poor oral hygiene, plaque accumulation, inflamed gingiva, compromised esthetics, and further progression to peri-implantitis. The coverage of exposed implants is aimed to provide adequate keratinized tissue around dental implant. Complete coverage of mucosal defect around the dental implants is still a challenging prospect. This case report describes correction of soft tissue defect and building up of keratinized tissue in relation to implant in the maxillary right first premolar region with subepithelial connective tissue graft along with coronally advanced flap.

  5. [New Croatian legislation on tissue banking].

    Science.gov (United States)

    Busić, Mirela

    2007-12-01

    Human tissues and cells are increasingly used in transplantation, and have also a very promising potential as starting material for tissue engineering and cell therapy. Due to their biological origin, tissues and cells also carry the risks of disease transmission, which need to be reduced as far as possible. Safety and quality standards for tissues and cells have to be concurrent with EU standards in all member states. EU standards in this area have been regulated by the Directive 2004/23/EC, which determines safety and quality standards for human tissues and cells. Two other directives support its implementation regulating technical requirements regarding different process phases of handling tissues and cells. Directive 2006/17/EC regulate technical requirements for donation, procurement and testing of human tissues and cells, whereas technical requirements concerning coding, processing, preservation, storage and distribution of human tissues and cells are regulated by Directive 2006/86/EC. Legal implementations of these directives throughout the European Union take places at different dynamic levels. Countries like Spain, Ireland, Denmark and Bulgaria have successfully completed this process. However, some countries have not met this challenge yet (e.g., Italy, The Netherlands, Latvia, Belgium, Luxembourg, Austria, Slovenia and Sweden), and others are only half-way through (e.g. Slovakia, Rumania, Portugal, Norway, Great Britain, et aI.). Some Member States indicated problems in the implementation of the Directive due to the limited number of experts in the field. In Croatia, the field of tissue and cell transplants is regulated by the Act of Conditions for Removal and Transplantation of Human Body Parts for Therapeutic Purposes (Official Gazette 177/04) and other decrees, which help regulating quality and safety for human tissues and cells, defining authorization systems for tissue and cell banks as well as supervising their work and determining the compliance

  6. Nanoreinforced Hydrogels for Tissue Engineering: Biomaterials that are Compatible with Load-Bearing and Electroactive Tissues

    DEFF Research Database (Denmark)

    Mehrali, Mehdi; Thakur, Ashish; Pennisi, Christian Pablo

    2017-01-01

    , mechanical, and electrical properties. Here, recent advances in the fabrication and application of nanocomposite hydrogels in tissue engineering applications are described, with specific attention toward skeletal and electroactive tissues, such as cardiac, nerve, bone, cartilage, and skeletal muscle......Given their highly porous nature and excellent water retention, hydrogel-based biomaterials can mimic critical properties of the native cellular environment. However, their potential to emulate the electromechanical milieu of native tissues or conform well with the curved topology of human organs...

  7. Tissue damage thresholds during therapeutic electrical stimulation

    Science.gov (United States)

    Cogan, Stuart F.; Ludwig, Kip A.; Welle, Cristin G.; Takmakov, Pavel

    2016-04-01

    Objective. Recent initiatives in bioelectronic modulation of the nervous system by the NIH (SPARC), DARPA (ElectRx, SUBNETS) and the GlaxoSmithKline Bioelectronic Medicines effort are ushering in a new era of therapeutic electrical stimulation. These novel therapies are prompting a re-evaluation of established electrical thresholds for stimulation-induced tissue damage. Approach. In this review, we explore what is known and unknown in published literature regarding tissue damage from electrical stimulation. Main results. For macroelectrodes, the potential for tissue damage is often assessed by comparing the intensity of stimulation, characterized by the charge density and charge per phase of a stimulus pulse, with a damage threshold identified through histological evidence from in vivo experiments as described by the Shannon equation. While the Shannon equation has proved useful in assessing the likely occurrence of tissue damage, the analysis is limited by the experimental parameters of the original studies. Tissue damage is influenced by factors not explicitly incorporated into the Shannon equation, including pulse frequency, duty cycle, current density, and electrode size. Microelectrodes in particular do not follow the charge per phase and charge density co-dependence reflected in the Shannon equation. The relevance of these factors to tissue damage is framed in the context of available reports from modeling and in vivo studies. Significance. It is apparent that emerging applications, especially with microelectrodes, will require clinical charge densities that exceed traditional damage thresholds. Experimental data show that stimulation at higher charge densities can be achieved without causing tissue damage, suggesting that safety parameters for microelectrodes might be distinct from those defined for macroelectrodes. However, these increased charge densities may need to be justified by bench, non-clinical or clinical testing to provide evidence of device

  8. Tissue-resident memory T cells.

    Science.gov (United States)

    Shin, Haina; Iwasaki, Akiko

    2013-09-01

    Tissues such as the genital tract, skin, and lung act as barriers against invading pathogens. To protect the host, incoming microbes must be quickly and efficiently controlled by the immune system at the portal of entry. Memory is a hallmark of the adaptive immune system, which confers long-term protection and is the basis for efficacious vaccines. While the majority of existing vaccines rely on circulating antibody for protection, struggles to develop antibody-based vaccines against infections such as herpes simplex virus (HSV) and human immunodeficiency virus (HIV) have underscored the need to generate memory T cells for robust antiviral control. The circulating memory T-cell population is generally divided into two subsets: effector memory (TEM ) and central memory (TCM ). These two subsets can be distinguished by their localization, as TCM home to secondary lymphoid organs and TEM circulate through non-lymphoid tissues. More recently, studies have identified a third subset, called tissue-resident memory (TRM ) cells, based on its migratory properties. This subset is found in peripheral tissues that require expression of specific chemoattractants and homing receptors for T-cell recruitment and retention, including barrier sites such as the skin and genital tract. In this review, we categorize different tissues in the body based on patterns of memory T-cell migration and tissue residency. This review also describes the rules for TRM generation and the properties that distinguish them from circulating TEM and TCM cells. Finally, based on the failure of recent T-cell-based vaccines to provide optimal protection, we also discuss the potential role of TRM cells in vaccine design against microbes that invade through the peripheral tissues and highlight new vaccination strategies that take advantage of this newly described memory T-cell subset. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Stratified scaffold design for engineering composite tissues.

    Science.gov (United States)

    Mosher, Christopher Z; Spalazzi, Jeffrey P; Lu, Helen H

    2015-08-01

    A significant challenge to orthopaedic soft tissue repair is the biological fixation of autologous or allogeneic grafts with bone, whereby the lack of functional integration between such grafts and host bone has limited the clinical success of anterior cruciate ligament (ACL) and other common soft tissue-based reconstructive grafts. The inability of current surgical reconstruction to restore the native fibrocartilaginous insertion between the ACL and the femur or tibia, which minimizes stress concentration and facilitates load transfer between the soft and hard tissues, compromises the long-term clinical functionality of these grafts. To enable integration, a stratified scaffold design that mimics the multiple tissue regions of the ACL interface (ligament-fibrocartilage-bone) represents a promising strategy for composite tissue formation. Moreover, distinct cellular organization and phase-specific matrix heterogeneity achieved through co- or tri-culture within the scaffold system can promote biomimetic multi-tissue regeneration. Here, we describe the methods for fabricating a tri-phasic scaffold intended for ligament-bone integration, as well as the tri-culture of fibroblasts, chondrocytes, and osteoblasts on the stratified scaffold for the formation of structurally contiguous and compositionally distinct regions of ligament, fibrocartilage and bone. The primary advantage of the tri-phasic scaffold is the recapitulation of the multi-tissue organization across the native interface through the layered design. Moreover, in addition to ease of fabrication, each scaffold phase is similar in polymer composition and therefore can be joined together by sintering, enabling the seamless integration of each region and avoiding delamination between scaffold layers. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Characterization of regulatory features of housekeeping and tissue-specific regulators within tissue regulatory networks.

    Science.gov (United States)

    Li, Pengping; Hua, Xu; Zhang, Zhen; Li, Jie; Wang, Jin

    2013-10-31

    Transcription factors (TFs) and miRNAs are essential for the regulation of gene expression; however, the global view of human gene regulatory networks remains poorly understood. For example, how is the expression of so many genes regulated by limited cohorts of regulators and how are genes differentially expressed in different tissues despite the genetic code being the same in all tissues? We analyzed the network properties of housekeeping and tissue-specific genes in gene regulatory networks from seven human tissues. Our results show that different classes of genes behave quite differently in these networks. Tissue-specific miRNAs show a higher average target number compared with non-tissue specific miRNAs, which indicates that tissue-specific miRNAs tend to regulate different sets of targets. Tissue-specific TFs exhibit higher in-degree, out-degree, cluster coefficient and betweenness values, indicating that they occupy central positions in the regulatory network and that they transfer genetic information from upstream genes to downstream genes more quickly than other TFs. Housekeeping TFs tend to have higher cluster coefficients compared with other genes that are neither housekeeping nor tissue specific, indicating that housekeeping TFs tend to regulate their targets synergistically. Several topological properties of disease-associated miRNAs and genes were found to be significantly different from those of non-disease-associated miRNAs and genes. Tissue-specific miRNAs, TFs and disease genes have particular topological properties within the transcriptional regulatory networks of the seven human tissues examined. The tendency of tissue-specific miRNAs to regulate different sets of genes shows that a particular tissue-specific miRNA and its target gene set may form a regulatory module to execute particular functions in the process of tissue differentiation. The regulatory patterns of tissue-specific TFs reflect their vital role in regulatory networks and their

  11. Mesenchymal cells for skeletal tissue engineering.

    Science.gov (United States)

    Panetta, N J; Gupta, D M; Quarto, N; Longaker, M T

    2009-03-01

    Today, surgical intervention remains the mainstay of treatment to intervene upon a multitude of skeletal deficits and defects attributable to congenital malformations, oncologic resection, pathologic degenerative bone destruction, and post-traumatic loss. Despite this significant demand, the tools with which surgeons remain equipped are plagued with a surfeit of inadequacies, often resulting in less than ideal patient outcomes. The failings of current techniques largely arise secondary to their inability to produce a regenerate which closely resembles lost tissue. As such, focus has shifted to the potential of mesenchymal stem cell (MSC)-based skeletal tissue engineering. The successful development of such techniques would represent a paradigm shift from current approaches, carrying with it the potential to regenerate tissues which mimic the form and function of endogenous bone. Lessons learned from investigations probing the endogenous regenerative capacity of skeletal tissues have provided direction to early studies investigating the osteogenic potential of MSC. Additionally, increasing attention is being turned to the role of targeted molecular manipulations in augmenting MSC osteogenesis, as well as the development of an ideal scaffold ''vehicle'' with which to deliver progenitor cells. The following discussion presents the authors' current working knowledge regarding these critical aspects of MSC application in cell-based skeletal tissue engineering strategies, as well as provides insight towards what future steps must be taken to make their clinical translation a reality.

  12. Isolation of microbodies from plant tissues.

    Science.gov (United States)

    Huang, A H; Beevers, H

    1971-11-01

    Specialized microbodies have previously been isolated and characterized from fatty seedling tissues (glyoxysomes) and leaves (leaf peroxisomes). We have now examined 11 other plant tissues, including tubers, fruits, roots, shoots, and petals, and find that all contain particulate catalase, a distinctive common enzyme component of microbodies. On linear sucrose gradients the catalase activity peaks sharply at a higher equilibrium density (1.20 to 1.25 gram per cm(3) in the various tissues) than the mitochondria (1.17 to 1.20). Only small amounts of protein are recovered in the fractions containing catalase, although a definite band is visible in preparations from some tissues, e.g., potato. As in the preparations from castor bean endosperm and spinach leaves for which comparable data are provided, the distribution of glycolate oxidase and uricase follows closely that of catalase on the gradients. The preparations from potato lack glyoxylate reductase and the transaminases, typical enzymes of leaf peroxisomes, and the distinctive enzymes of glyoxysomes are missing. Nonspecialized microbodies with limited enzyme composition can thus be isolated from a variety of plant tissues.

  13. Connective tissue: Vascular and hematological (blood) support.

    Science.gov (United States)

    Calvino, Nick

    2003-01-01

    Connective Tissue (CT) is a ubiquitous component of all major tissues and structures of the body (50% of all body protein is CT), including that of the blood, vascular, muscle, tendon, ligament, fascia, bone, joint, IVD's (intervertebral discs) and skin. Because of its ubiquitous nature, CT is an often overlooked component of any essential nutritional program that may address the structure, and/or function of these tissues. The central role of CT in the health of a virtually all cells, tissues, organs, and organ systems, is discussed. General nutritional CT support strategies, as well as specific CT support strategies that focus on blood, vascular, structural system (eg, muscles, tendons, ligaments, fascia, bone, and joints), integument (skin) and inflammatory and immune mediation will be discussed here and will deal with connective tissue dynamics and dysfunction. An overview of the current scientific understanding and possible options for naturally enhancing the structure and function of CT through the application of these concepts will be discussed in this article, with specific attention on the vascular and hematological systems.

  14. Recombinant protein scaffolds for tissue engineering

    International Nuclear Information System (INIS)

    Werkmeister, Jerome A; Ramshaw, John A M

    2012-01-01

    New biological materials for tissue engineering are now being developed using common genetic engineering capabilities to clone and express a variety of genetic elements that allow cost-effective purification and scaffold fabrication from these recombinant proteins, peptides or from chimeric combinations of these. The field is limitless as long as the gene sequences are known. The utility is dependent on the ease, product yield and adaptability of these protein products to the biomedical field. The development of recombinant proteins as scaffolds, while still an emerging technology with respect to commercial products, is scientifically superior to current use of natural materials or synthetic polymer scaffolds, in terms of designing specific structures with desired degrees of biological complexities and motifs. In the field of tissue engineering, next generation scaffolds will be the key to directing appropriate tissue regeneration. The initial period of biodegradable synthetic scaffolds that provided shape and mechanical integrity, but no biological information, is phasing out. The era of protein scaffolds offers distinct advantages, particularly with the combination of powerful tools of molecular biology. These include, for example, the production of human proteins of uniform quality that are free of infectious agents and the ability to make suitable quantities of proteins that are found in low quantity or are hard to isolate from tissue. For the particular needs of tissue engineering scaffolds, fibrous proteins like collagens, elastin, silks and combinations of these offer further advantages of natural well-defined structural scaffolds as well as endless possibilities of controlling functionality by genetic manipulation. (topical review)

  15. 3D bioprinting for engineering complex tissues.

    Science.gov (United States)

    Mandrycky, Christian; Wang, Zongjie; Kim, Keekyoung; Kim, Deok-Ho

    2016-01-01

    Bioprinting is a 3D fabrication technology used to precisely dispense cell-laden biomaterials for the construction of complex 3D functional living tissues or artificial organs. While still in its early stages, bioprinting strategies have demonstrated their potential use in regenerative medicine to generate a variety of transplantable tissues, including skin, cartilage, and bone. However, current bioprinting approaches still have technical challenges in terms of high-resolution cell deposition, controlled cell distributions, vascularization, and innervation within complex 3D tissues. While no one-size-fits-all approach to bioprinting has emerged, it remains an on-demand, versatile fabrication technique that may address the growing organ shortage as well as provide a high-throughput method for cell patterning at the micrometer scale for broad biomedical engineering applications. In this review, we introduce the basic principles, materials, integration strategies and applications of bioprinting. We also discuss the recent developments, current challenges and future prospects of 3D bioprinting for engineering complex tissues. Combined with recent advances in human pluripotent stem cell technologies, 3D-bioprinted tissue models could serve as an enabling platform for high-throughput predictive drug screening and more effective regenerative therapies. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Tissue adhesives for simple traumatic lacerations.

    Science.gov (United States)

    Beam, Joel W

    2008-01-01

    Farion K, Osmond MH, Hartling L, et al. Tissue adhesives for traumatic lacerations in children and adults. Cochrane Database Syst Rev. 2001(4);CD003326. What is the clinical evidence base for tissue adhesives in the management of simple traumatic lacerations? Studies were identified by searches of the following databases: Cochrane Wounds Group Specialized Trials Register (September 2003), Cochrane Central Register of Controlled Trials (CENTRAL) (CDROM 2003, issue 3), MEDLINE (1966 to September 2003, week 1), EMBASE (1988 to 2003, week 36), Web of Science Science Citation Index (1975 to September 13, 2003) and various clinical trials registers (September 2003). Investigators and product manufacturers were contacted to identify additional eligible studies. The search terms included wounds and injuries, laceration, face injury, nose injury, tissue adhesives, and acrylates. Each study fulfilled the following criteria: (1) The study was a randomized controlled trial that compared tissue adhesives with standard wound closure (SWC) (sutures, staples, adhesive strips) or tissue adhesive with tissue adhesive. (2) The wounds were acute, linear lacerations less than 12 hours old, resulting from blunt or sharp trauma. (3) The wound length, width, and depth allowed for approximation of the edges with minimal tension after deep sutures were placed, if required. Studies were included with no language or publication status restriction, with participants of any age recruited in an emergency department, outpatient clinic, walk-in clinic, or other primary care setting. Studies were excluded if the wounds were stellate lacerations, puncture wounds, mammalian bites, infected, heavily contaminated or devitalized, crossing joints or mucocutaneous junctions, in hair-bearing areas, or in patients with keloid formation or chronic illness. The characteristics of the study and participants, interventions, outcome measures, and findings were extracted by one author and verified by a second

  17. Automated 3D bioassembly of micro-tissues for biofabrication of hybrid tissue engineered constructs.

    Science.gov (United States)

    Mekhileri, N V; Lim, K S; Brown, G C J; Mutreja, I; Schon, B S; Hooper, G J; Woodfield, T B F

    2018-01-12

    Bottom-up biofabrication approaches combining micro-tissue fabrication techniques with extrusion-based 3D printing of thermoplastic polymer scaffolds are emerging strategies in tissue engineering. These biofabrication strategies support native self-assembly mechanisms observed in developmental stages of tissue or organoid growth as well as promoting cell-cell interactions and cell differentiation capacity. Few technologies have been developed to automate the precise assembly of micro-tissues or tissue modules into structural scaffolds. We describe an automated 3D bioassembly platform capable of fabricating simple hybrid constructs via a two-step bottom-up bioassembly strategy, as well as complex hybrid hierarchical constructs via a multistep bottom-up bioassembly strategy. The bioassembly system consisted of a fluidic-based singularisation and injection module incorporated into a commercial 3D bioprinter. The singularisation module delivers individual micro-tissues to an injection module, for insertion into precise locations within a 3D plotted scaffold. To demonstrate applicability for cartilage tissue engineering, human chondrocytes were isolated and micro-tissues of 1 mm diameter were generated utilising a high throughput 96-well plate format. Micro-tissues were singularised with an efficiency of 96.0 ± 5.1%. There was no significant difference in size, shape or viability of micro-tissues before and after automated singularisation and injection. A layer-by-layer approach or aforementioned bottom-up bioassembly strategy was employed to fabricate a bilayered construct by alternatively 3D plotting a thermoplastic (PEGT/PBT) polymer scaffold and inserting pre-differentiated chondrogenic micro-tissues or cell-laden gelatin-based (GelMA) hydrogel micro-spheres, both formed via high-throughput fabrication techniques. No significant difference in viability between the construct assembled utilising the automated bioassembly system and manually assembled construct was

  18. Tissue banking and clinical research on radiation and ethylene oxide sterilization of tissue grafts

    International Nuclear Information System (INIS)

    Pe Khin

    1987-06-01

    The research works carried out in Rangoon, Burma under the Agency supported project RC4420/RB have dealt with an elucidation of the radiation interaction(s) with the species of biomolecules such as proteins, lipids, collagens, connective tissues present in the cleaned and freeze-dried non-viable tissue grafts. Radiation as a cool process furthermore effectively helps to destroy the microbial bioburden as the undesirable contaminants which may associate the tissue grafts. Radiation also concomitantly helps to suppress the tissue-specific immunogenicity. All these attributes of radiation induced effects have proved successful towards the development of a sterilization process. A series of non-viable tissue grafts, such as bone, nerve, fascia, dura, cartilage, chorion-amnion (as dressings in burn wounds) and tympanic membrane have been successfully attempted in Burma and many more possibilities seem to still remain unexplored. Radiation sterilization modality has proved as a blessing for the promotion of clinical surgical applications of tissue allografts in the corrective/reconstructive surgery on the disability cases due to diseases which accompany tissue losses. The investigator in Burma has reported on the case histories where freeze dried radiation sterilized tissue allografts have been successfully used in the osteogenic inductions (bone grafts); midear tympanoplasty; partial recovery of nerve sensation throught nerve allografts; rapid healing of high degree burn wounds through the use of amnion dressings. Besides, there have been a widespread surgical use of radiation sterilized dura and fascia as allografts. A national tissue banking facility has been established in Burma surrounding the processing and clinical utilization of tissue allografts which has involved over ten hospital centres throughout the country. Radiation induced effects on the biomolecules of clinical significance in the tissue grafts have been researched to help gain insight into a better

  19. Biomimetic electrospun nanofibers for tissue regeneration

    International Nuclear Information System (INIS)

    Liao, Susan; Li Bojun; Ma Zuwei; Wei He; Chan Casey; Ramakrishna, Seeram

    2006-01-01

    Nanofibers exist widely in human tissue with different patterns. Electrospinning nanotechnology has recently gained a new impetus due to the introduction of the concept of biomimetic nanofibers for tissue regeneration. The advanced electrospinning technique is a promising method to fabricate a controllable continuous nanofiber scaffold similar to the natural extracellular matrix. Thus, the biomedical field has become a significant possible application field of electrospun fibers. Although electrospinning has developed rapidly over the past few years, electrospun nanofibers are still at a premature research stage. Further comprehensive and deep studies on electrospun nanofibers are essential for promoting their biomedical applications. Current electrospun fiber materials include natural polymers, synthetic polymers and inorganic substances. This review briefly describes several typically electrospun nanofiber materials or composites that have great potential for tissue regeneration, and describes their fabrication, advantages, drawbacks and future prospects. (topical review)

  20. Soft-tissue mineralization in Werner syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Leone, Antonio; Costantini, Alessandro Maria; Brigida, Raffaela; Antoniol, Onorina Monica; Bonomo, Lorenzo [Universita Cattolica School of Medicine, Department of Radiology, Rome (Italy); Antonelli-Incalzi, Raffaele [Universita Cattolica School of Medicine, Department of Geriatrics, Rome (Italy)

    2005-01-01

    Werner syndrome is a rare autosomal recessive disorder characterized by clinical signs of premature aging, short stature, scleroderma-like skin changes, endocrine abnormalities, cataracts, and an increased incidence of malignancies. We report on a 48-year-old woman with Werner syndrome associated with intracranial meningiomas who had extensive musculoskeletal manifestations including osteoporosis of the extremities, extensive tendinopathy about the ankles, osteomyelitis of the phalanges of the first left toe, abundant soft-tissue calcification, and two dense ossified soft-tissue masses, with cortical bone and trabeculae arising from the posterosuperior aspect of the calcanei and extending into Kager fat pads. A review of previous descriptions of the radiological abnormalities of Werner syndrome indicates that the presence of soft-tissue calcifications has either not been noted or been mentioned only briefly. Moreover, there is no mention of bony masses associated with Werner syndrome in the world literature, and this would appear to be the first report of this kind. (orig.)

  1. Subcutaneous tissue flaps for hallux covering.

    Science.gov (United States)

    Vaienti, Luca; Urzola, Victor; Scotti, Andrea; Masetto, L

    2010-03-01

    With the understanding of the extensive vascular supply of the subcutaneous tissue, of its efficacy in the protection of the anatomical structures and of its capability of promoting the adequate functioning of very stressed regions of the human body, the use of subcutaneous adipose flaps has become a valid and sometimes the only reasonable therapeutic weapon in the treatment of small and medium-sized tissue loss. Such a defect represents a common complication of great toe injuries and surgery. Here subcutaneous flap reconstruction is proposed for the treatment of dorsal and medial soft tissue losses of the hallux complicated with infection. Two case are reported. To the best of the authors' knowledge, this application has not been reported in this anatomical site so far. The technique might be worth knowing both for orthopedic and plastic surgeons, as it may represent a safe, less invasive solution for most tegumentary problems of the dorso-medial side of the first ray.

  2. Damage Models for Soft Tissues: A Survey.

    Science.gov (United States)

    Li, Wenguang

    Damage to soft tissues in the human body has been investigated for applications in healthcare, sports, and biomedical engineering. This paper reviews and classifies damage models for soft tissues to summarize achievements, identify new directions, and facilitate finite element analysis. The main ideas of damage modeling methods are illustrated and interpreted. A few key issues related to damage models, such as experimental data curve-fitting, computational effort, connection between damage and fractures/cracks, damage model applications, and fracture/crack extension simulation, are discussed. Several new challenges in the field are identified and outlined. This review can be useful for developing more advanced damage models and extending damage modeling methods to a variety of soft tissues.

  3. Models of defibrillation of cardiac tissue

    Science.gov (United States)

    Krinsky, V.; Pumir, A.

    1998-03-01

    Heterogeneities, such as gap junctions, defects in periodical cellular lattices, intercellular clefts and fiber curvature allow one to understand the effect of an electric field in cardiac tissue. They induce membrane potential variations even in the bulk of the myocardium, with a characteristic sawtooth shape. The sawtooth potential, induced by heterogeneities at large scales (tissue strands) can be more easily observed, and lead to stronger effects than the one induced at the cellular level. In the generic model of propagation in cardiac tissue (FitzHugh), 4 mechanisms of defibrillation were found, two mechanisms based on excitation (EA,EM), and two—on de-excitation (DA,DM). The lowest electric field is required by an EM mechanism. In the Beeler-Reuter ionic model, mechanism DM is impossible. We critically review the experimental basis of the theory and propose new experiments.

  4. Developing 3D microstructures for tissue engineering

    DEFF Research Database (Denmark)

    Mohanty, Soumyaranjan

    casting process to generate various large scale tissue engineering constructs with single pore geometry with the desired mechanical stiffness and porosity. In addition, a new technique was developed to fa bricate dual-pore scaffolds for various tissue-engineering applications where 3D printing...... of a hydrogel to create an additional interpenetrating network (IPN) of hydrogel nanodeposits. Biocompatible IPNs of silicone elastomer with poly(2-hydroxyethyl methacrylate) (pHEMA) and Poly(ethylene glycol) methylether acrylate (PEGMEA) hydrogel 3D scaffolds were produced in this way. The model drug...... of hiPSC-derived DE cells cultured for 25 days in a 3D perfusion bioreactor system with an array of 16 small-scale tissue-bioreactors with integrated dual-pore pore scaffolds and flow rates. Hepatic differentiation and functionality of hiPSC-derived hepatocytes were successfully assessed and compared...

  5. Tissue Engineering in Regenerative Dental Therapy

    Directory of Open Access Journals (Sweden)

    Hiral Jhaveri-Desai

    2011-01-01

    Full Text Available Tissue engineering is amongst the latest exciting technologies having impacted the field of dentistry. Initially considered as a futuristic approach, tissue engineering is now being successfully applied in regenerative surgery. This article reviews the important determinants of tissue engineering and how they contribute to the improvement of wound healing and surgical outcomes in the oral region. Furthermore, we shall address the clinical applications of engineering involving oral and maxillofacial surgical and periodontal procedures along with other concepts that are still in experimental phase of development. This knowledge will aid the surgical and engineering researchers to comprehend the collaboration between these fields leading to extounding dental applications and to ever-continuing man-made miracles in the field of human science.

  6. Controlled drug release for tissue engineering.

    Science.gov (United States)

    Rambhia, Kunal J; Ma, Peter X

    2015-12-10

    Tissue engineering is often referred to as a three-pronged discipline, with each prong corresponding to 1) a 3D material matrix (scaffold), 2) drugs that act on molecular signaling, and 3) regenerative living cells. Herein we focus on reviewing advances in controlled release of drugs from tissue engineering platforms. This review addresses advances in hydrogels and porous scaffolds that are synthesized from natural materials and synthetic polymers for the purposes of controlled release in tissue engineering. We pay special attention to efforts to reduce the burst release effect and to provide sustained and long-term release. Finally, novel approaches to controlled release are described, including devices that allow for pulsatile and sequential delivery. In addition to recent advances, limitations of current approaches and areas of further research are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Primary Kaposi sarcoma of the subcutaneous tissue

    Directory of Open Access Journals (Sweden)

    Dezube Bruce J

    2008-09-01

    Full Text Available Abstract Background Involvement of the subcutis by Kaposi sarcoma (KS occurs primarily when cutaneous KS lesions evolve into deep penetrating nodular tumors. Primary KS of the subcutaneous tissue is an exceptional manifestation of this low-grade vascular neoplasm. Case presentation We present a unique case of acquired immune deficiency syndrome (AIDS-associated KS manifesting primarily in the subcutaneous tissue of the anterior thigh in a 43-year-old male, which occurred without overlying visible skin changes or concomitant KS disease elsewhere. Radiological imaging and tissue biopsy confirmed the diagnosis of KS. Conclusion This is the first documented case of primary subcutaneous KS occurring in the setting of AIDS. The differential diagnosis of an isolated subcutaneous lesion in an human immunodeficiency virus (HIV-infected individual is broad, and requires both imaging and a histopathological diagnosis to guide appropriate therapy.

  8. Multimodal imaging of cutaneous wound tissue

    Science.gov (United States)

    Zhang, Shiwu; Gnyawali, Surya; Huang, Jiwei; Ren, Wenqi; Gordillo, Gayle; Sen, Chandan K.; Xu, Ronald

    2015-01-01

    Quantitative assessment of wound tissue ischemia, perfusion, and inflammation provides critical information for appropriate detection, staging, and treatment of chronic wounds. However, few methods are available for simultaneous assessment of these tissue parameters in a noninvasive and quantitative fashion. We integrated hyperspectral, laser speckle, and thermographic imaging modalities in a single-experimental setup for multimodal assessment of tissue oxygenation, perfusion, and inflammation characteristics. Algorithms were developed for appropriate coregistration between wound images acquired by different imaging modalities at different times. The multimodal wound imaging system was validated in an occlusion experiment, where oxygenation and perfusion maps of a healthy subject's upper extremity were continuously monitored during a postocclusive reactive hyperemia procedure and compared with standard measurements. The system was also tested in a clinical trial where a wound of three millimeters in diameter was introduced on a healthy subject's lower extremity and the healing process was continuously monitored. Our in vivo experiments demonstrated the clinical feasibility of multimodal cutaneous wound imaging.

  9. Transplantation of frozen-thawed ovarian tissue

    DEFF Research Database (Denmark)

    Gellert, S E; Pors, S E; Kristensen, Stine Gry

    2018-01-01

    . CONCLUSION: This study found no indications of sufficient numbers of malignant cells present in the ovarian tissue to cause recurrence of cancer after OTT. Further, it is unlikely that OTC affects the well-being of children born. OTC is now an established method of fertility preservation in Denmark......PURPOSE: The purpose of the study is to review all peer-reviewed published reports of women receiving ovarian tissue transplantation (OTT) with frozen/thawed tissue (OTC) with respect to age, diagnosis, transplantation site, fertility outcome, and potential side effects, including data from all...... women in the Danish program. METHODS: A systematic review of the literature was performed in PubMed combined with results from all patients who had received OTT in Denmark up to December 2017. RESULTS: OTT has been reported from 21 different countries comprising a total of 360 OTT procedures in 318...

  10. Necrotising soft tissue infection following mastectomy

    Directory of Open Access Journals (Sweden)

    Jackson P

    2010-03-01

    Full Text Available Necrotising fasciitis is a rare but rapidly progressive soft tissue disease which can lead to extensive necrosis, systemic sepsis and death. Including this case, only 7 other cases have been reported in the world literature with only 2 others affecting the patient post mastectomy.This 59 year old Caucasian lady presented with severe soft tissue infection soon after mastectomy, which was successfully treated with a combination of debridement, triangulation, VAC© dressing and skin grafting.Necrotising soft tissue infections following mastectomy are rapidly progressive and potentially extremely serious. It is essential that a high index of clinical suspicion is maintained together with prompt aggressive treatment in a multidisciplinary environment to prevent worsening physical and psychological sequelae.

  11. Mechanisms of lymphatic regeneration after tissue transfer.

    Directory of Open Access Journals (Sweden)

    Alan Yan

    2011-02-01

    Full Text Available Lymphedema is the chronic swelling of an extremity that occurs commonly after lymph node resection for cancer treatment. Recent studies have demonstrated that transfer of healthy tissues can be used as a means of bypassing damaged lymphatics and ameliorating lymphedema. The purpose of these studies was to investigate the mechanisms that regulate lymphatic regeneration after tissue transfer.Nude mice (recipients underwent 2-mm tail skin excisions that were either left open or repaired with full-thickness skin grafts harvested from donor transgenic mice that expressed green fluorescent protein in all tissues or from LYVE-1 knockout mice. Lymphatic regeneration, expression of VEGF-C, macrophage infiltration, and potential for skin grafting to bypass damaged lymphatics were assessed.Skin grafts healed rapidly and restored lymphatic flow. Lymphatic regeneration occurred beginning at the peripheral edges of the graft, primarily from ingrowth of new lymphatic vessels originating from the recipient mouse. In addition, donor lymphatic vessels appeared to spontaneously re-anastomose with recipient vessels. Patterns of VEGF-C expression and macrophage infiltration were temporally and spatially associated with lymphatic regeneration. When compared to mice treated with excision only, there was a 4-fold decrease in tail volumes, 2.5-fold increase in lymphatic transport by lymphoscintigraphy, 40% decrease in dermal thickness, and 54% decrease in scar index in skin-grafted animals, indicating that tissue transfer could bypass damaged lymphatics and promote rapid lymphatic regeneration.Our studies suggest that lymphatic regeneration after tissue transfer occurs by ingrowth of lymphatic vessels and spontaneous re-connection of existing lymphatics. This process is temporally and spatially associated with VEGF-C expression and macrophage infiltration. Finally, tissue transfer can be used to bypass damaged lymphatics and promote rapid lymphatic regeneration.

  12. Accumulation of ethoxyquin in the tissue

    International Nuclear Information System (INIS)

    Kim, H.L.

    1991-01-01

    Ethoxyquin (EQ) residue levels in the mouse tissue were determined by the HPLC-fluorometric detection method. Mice were given powdered feed containing 0, 0.125, and 0.5% EQ HCl and the EQ residue levels in liver, kidney, lung, and brain tissues were determined after 2, 4, 6, 10, and 14 wk (4 mice/group). The tissue samples were homogenized in 10 volumes (w/v) of acetonitrile-water (7:3, v/v), centrifuged, and the supernatants were stored in a freezer for 2-3 h or until the two layers separated; then the clear upper layers were analyzed. The mean EQ residue levels in the tissue ranged 0.84-4.58 micrograms EQ/g liver and 0.11-0.92 micrograms EQ/g brain. The relative weight of the liver (5.21-7.07% body weight) and the hepatic glutathione level (5.99-7.83 microM GSH/g tissue) of mice that received EQ were significantly higher than those of the controls (4.67-5.05% body weight and 4.30-5.78 microM GSH/g tissue, respectively). The mean hepatic mitochondrial glutathione level of the higher EQ feeding group, following dietary administration of EQ for 14 wk, was approximately twofold (1.68 nM GSH/mg protein) of both the control and the lower EQ feeding groups (0.83 and 0.74 nM GSH/mg protein, respectively)

  13. Chemical sterilization of allograft dermal tissues.

    Science.gov (United States)

    Phipps, Abigail; Vaynshteyn, Edward; Kowalski, John B; Ngo, Manh-Dan; Merritt, Karen; Osborne, Joel; Chnari, Evangelia

    2017-12-01

    Common terminal sterilization methods are known to alter the natural structure and properties of soft tissues. One approach to providing safe grafts with preserved biological properties is the combination of a validated chemical sterilization process followed by an aseptic packaging process. This combination of processes is an accepted method for production of sterile healthcare products as described in ANSI/AAMI ST67:2011. This article describes the validation of the peracetic acid and ethanol-based (PAAE) chemical sterilization process for allograft dermal tissues at the Musculoskeletal Transplant Foundation (MTF, Edison, NJ). The sterilization capability of the PAAE solution used during routine production of aseptically processed dermal tissue forms was determined based on requirements of relevant ISO standards, ISO 14161:2009 and ISO 14937:2009. The resistance of spores of Bacillus subtilis, Clostridium sporogenes, Mycobacterium terrae, Pseudomonas aeruginosa, Enterococcus faecium, and Staphylococcus aureus to the chemical sterilization process employed by MTF was determined. Using a worst-case scenario testing strategy, the D value was calculated for the most resistant microorganism, Bacillus. The 12D time parameter determined the minimum time required to achieve a SAL of 10 -6 . Microbiological performance qualification demonstrated a complete kill of 10 6 spores at just a quarter of the full cycle time. The validation demonstrated that the PAAE sterilization process is robust, achieves sterilization of allograft dermal tissue to a SAL 10 -6 , and that in combination with aseptic processing secures the microbiological safety of allograft dermal tissue while avoiding structural and biochemical tissue damage previously observed with other sterilization methods such as ionizing irradiation.

  14. Live tissue versus simulation training for emergency procedures: Is simulation ready to replace live tissue?

    Science.gov (United States)

    Barnes, Stephen L; Bukoski, Alex; Kerby, Jeffrey D; Llerena, Luis; Armstrong, John H; Strayhorn, Catherine

    2016-10-01

    Training of emergency procedures is challenging and application is not routine in all health care settings. The debate over simulation as an alternative to live tissue training continues with legislation before Congress to banish live tissue training in the Department of Defense. Little evidence exists to objectify best practice. We sought to evaluate live tissue and simulation-based training practices in 12 life-saving emergency procedures. In the study, 742 subjects were randomized to live tissue or simulation-training. Assessments of self-efficacy, cognitive knowledge, and psychomotor performance were completed pre- and post-training. Affective response to training was assessed through electrodermal activity. Subject matter experts gap analysis of live tissue versus simulation completed the data set. Subjects demonstrated pre- to post-training gains in self-efficacy, cognitive knowledge, psychomotor performance, and affective response regardless of training modality (P Affective response was greatest in live tissue training (P abandonment of live tissue training is not warranted. We maintain that combined live tissue and simulation-based training add value and should be continued. Congressional mandates may accelerate simulation development and improve performance. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. The use of animal tissues alongside human tissue: Cultural and ethical considerations.

    Science.gov (United States)

    Kaw, Anu; Jones, D Gareth; Zhang, Ming

    2016-01-01

    Teaching and research facilities often use cadaveric material alongside animal tissues, although there appear to be differences in the way we handle, treat, and dispose of human cadaveric material compared to animal tissue. This study sought to analyze cultural and ethical considerations and provides policy recommendations on the use of animal tissues alongside human tissue. The status of human and animal remains and the respect because of human and animal tissues were compared and analyzed from ethical, legal, and cultural perspectives. The use of animal organs and tissues is carried out within the context of understanding human anatomy and function. Consequently, the interests of human donors are to be pre-eminent in any policies that are enunciated, so that if any donors find the presence of animal remains unacceptable, the latter should not be employed. The major differences appear to lie in differences in our perceptions of their respective intrinsic and instrumental values. Animals are considered to have lesser intrinsic value and greater instrumental value than humans. These differences stem from the role played by culture and ethical considerations, and are manifested in the resulting legal frameworks. In light of this discussion, six policy recommendations are proposed, encompassing the nature of consent, respect for animal tissues as well as human remains, and appropriate separation of both sets of tissues in preparation and display. © 2015 Wiley Periodicals, Inc.

  16. Ontology-based, Tissue MicroArray oriented, image centered tissue bank

    Directory of Open Access Journals (Sweden)

    Viti Federica

    2008-04-01

    Full Text Available Abstract Background Tissue MicroArray technique is becoming increasingly important in pathology for the validation of experimental data from transcriptomic analysis. This approach produces many images which need to be properly managed, if possible with an infrastructure able to support tissue sharing between institutes. Moreover, the available frameworks oriented to Tissue MicroArray provide good storage for clinical patient, sample treatment and block construction information, but their utility is limited by the lack of data integration with biomolecular information. Results In this work we propose a Tissue MicroArray web oriented system to support researchers in managing bio-samples and, through the use of ontologies, enables tissue sharing aimed at the design of Tissue MicroArray experiments and results evaluation. Indeed, our system provides ontological description both for pre-analysis tissue images and for post-process analysis image results, which is crucial for information exchange. Moreover, working on well-defined terms it is then possible to query web resources for literature articles to integrate both pathology and bioinformatics data. Conclusions Using this system, users associate an ontology-based description to each image uploaded into the database and also integrate results with the ontological description of biosequences identified in every tissue. Moreover, it is possible to integrate the ontological description provided by the user with a full compliant gene ontology definition, enabling statistical studies about correlation between the analyzed pathology and the most commonly related biological processes.

  17. Tissue type plasminogen activator regulates myeloid-cell dependent neoangiogenesis during tissue regeneration

    DEFF Research Database (Denmark)

    Ohki, Makiko; Ohki, Yuichi; Ishihara, Makoto

    2010-01-01

    tissue regeneration is not well understood. Bone marrow (BM)-derived myeloid cells facilitate angiogenesis during tissue regeneration. Here, we report that a serpin-resistant form of tPA by activating the extracellular proteases matrix metalloproteinase-9 and plasmin expands the myeloid cell pool...

  18. The Expanding World of Tissue Engineering: The Building Blocks and New Applications of Tissue Engineered Constructs

    Science.gov (United States)

    Zorlutuna, Pinar; Vrana, Nihal Engin; Khademhosseini, Ali

    2013-01-01

    The field of tissue engineering has been growing in the recent years as more products have made it to the market and as new uses for the engineered tissues have emerged, motivating many researchers to engage in this multidisciplinary field of research. Engineered tissues are now not only considered as end products for regenerative medicine, but also have emerged as enabling technologies for other fields of research ranging from drug discovery to biorobotics. This widespread use necessitates a variety of methodologies for production of tissue engineered constructs. In this review, these methods together with their non-clinical applications will be described. First, we will focus on novel materials used in tissue engineering scaffolds; such as recombinant proteins and synthetic, self assembling polypeptides. The recent advances in the modular tissue engineering area will be discussed. Then scaffold-free production methods, based on either cell sheets or cell aggregates will be described. Cell sources used in tissue engineering and new methods that provide improved control over cell behavior such as pathway engineering and biomimetic microenvironments for directing cell differentiation will be discussed. Finally, we will summarize the emerging uses of engineered constructs such as model tissues for drug discovery, cancer research and biorobotics applications. PMID:23268388

  19. NONSPECIFIC INFECTIONS OF THE BONE TISSUE

    Directory of Open Access Journals (Sweden)

    Zoran Golubovic

    2002-11-01

    Full Text Available Osteomyelitis represents an inflammation of the bone tissue caused by microorganisms. The cause of the inflammation can be bacteria, viruses and parasites. The bone infections are divided into specific and nonspecific. Regarding the course they take, they can be of acute or chronic form. Nonspecific bone infections are analyzed, namely, hematogenic and exogenous osteomyelitis. The most frequent complications of osteomyelitis are bone infection recidivism, pathological fractures, infection penetration into the joint, malign tissue alteration and amyloidosis as a consequence of the chronic infection.

  20. Tissue engineering applications in periodontics: Alternate god

    Directory of Open Access Journals (Sweden)

    Samir Chugh

    2014-01-01

    Full Text Available "Tissue engineering" also referred as regenerative medicine indicates a new interdisciplinary initiative, which has the goal of growing tissues or organs directly from a single cell taken from an individual. Originally coined to denote the construction in the laboratory of a device containing viable cells and biologic mediators in a synthetic or biologic matrix that could be implanted in patients to facilitate regeneration. However, the term has crept into clinical armory of periodontists and has attained certain halo and glamour even when used in mundane and prosaic situations. Thus, this paper critically evaluates its role and application in clinical scenario.

  1. Tissue proteomics of the human mammary gland

    DEFF Research Database (Denmark)

    Moreira, José Manuel Alfonso; Cabezón, Teresa; Gromova, Irina

    2010-01-01

    Our limited understanding of the biological impact of the whole spectrum of early breast lesions together with a lack of accurate molecular-based risk criteria for the diagnosis and assignment of prognostic significance to biopsy findings presents an important problem in the clinical management...... of these limitations and here we present our efforts to search for biomarkers using normal fresh tissue from non-neoplastic breast samples. From the data generated by the 2D gel-based proteomic profiling we were able to compile a protein database of normal human breast epithelial tissue that was used to support...

  2. Oriented Collagen Scaffolds for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Shohta Kodama

    2012-03-01

    Full Text Available Oriented collagen scaffolds were developed in the form of sheet, mesh and tube by arraying flow-oriented collagen string gels and dehydrating the arrayed gels. The developed collagen scaffolds can be any practical size with any direction of orientation for tissue engineering applications. The birefringence of the collagen scaffolds was quantitatively analyzed by parallel Nicols method. Since native collagen in the human body has orientations such as bone, cartilage, tendon and cornea, and the orientation has a special role for the function of human organs, the developed various types of three-dimensional oriented collagen scaffolds are expected to be useful biomaterials for tissue engineering and regenerative medicines.

  3. Radiogenomics: predicting clinical normal tissue radiosensitivity

    DEFF Research Database (Denmark)

    Alsner, Jan

    2006-01-01

    Studies on the genetic basis of normal tissue radiosensitivity, or  'radiogenomics', aims at predicting clinical radiosensitivity and optimize treatment from individual genetic profiles. Several studies have now reported links between variations in certain genes related to the biological response...... to radiation injury and risk of normal tissue morbidity in cancer patients treated with radiotherapy. However, after these initial association studies including few genes, we are still far from being able to predict clinical radiosensitivity on an individual level. Recent data from our own studies on risk...

  4. The autologus graft of epithelial tissue culture

    Directory of Open Access Journals (Sweden)

    Minaee B

    1999-08-01

    Full Text Available With the intention of research about culture and autologus graft of epithelial tissue we used 4 french Albino Rabbits with an average age of 2 months. After reproduction on the support in EMEM (Eagle's Minimum Essential Medium we used this for graft after 4 weeks. This region which grafted total replaced. After fixation of this sample and passing them through various process, histological sections were prepared. These sections were stained with H & E and masson's trichrome and studied by light microscope. We succeeded in graft. We hope in the near future by using the method of epithelium tissue culture improving to treat burned patients.

  5. Lung tissue classification using wavelet frames.

    Science.gov (United States)

    Depeursinge, Adrien; Sage, Daniel; Hidki, Asmâa; Platon, Alexandra; Poletti, Pierre-Alexandre; Unser, Michael; Müller, Henning

    2007-01-01

    We describe a texture classification system that identifies lung tissue patterns from high-resolution computed tomography (HRCT) images of patients affected with interstitial lung diseases (ILD). This pattern recognition task is part of an image-based diagnostic aid system for ILDs. Five lung tissue patterns (healthy, emphysema, ground glass, fibrosis and microdules) selected from a multimedia database are classified using the overcomplete discrete wavelet frame decompostion combined with grey-level histogram features. The overall multiclass accuracy reaches 92.5% of correct matches while combining the two types of features, which are found to be complementary.

  6. Cellular immunotherapy for soft tissue sarcomas

    Science.gov (United States)

    Finkelstein, Steven Eric; Fishman, Mayer; Conley, Anthony P.; Gabrilovich, Dmitry; Antonia, Scott; Chiappori, Alberto

    2015-01-01

    SUMMARY Soft tissue sarcomas are rare neoplasms, with approximately 9,000 new cases in the United States every year. Unfortunately, there is little progress in the treatment of metastatic soft tissue sarcomas in the past two decades beyond the standard approaches of surgery, chemotherapy, and radiation. Immunotherapy is a modality complementary to conventional therapy,. It is appealing because functional anti-tumor activity could affect both local-regional and systemic disease and act over a prolonged period of time. In this report, we review immunotherapeutic investigative strategies being developed, including several tumor vaccine, antigen vaccine, and dendritic cell vaccine strategies. PMID:22401634

  7. Alteration of tissue vanadium content in diabetes.

    Science.gov (United States)

    Hamel, F G; Solomon, S S; Jespersen, A S; Blotcky, A; Rack, E; Duckworth, W C

    1993-12-01

    A great deal of interest in the element vanadium has been generated recently because of its potential as a therapeutic agent for diabetes mellitus. Vanadium's insulin-mimetic properties and its requirement for proper growth and development suggest that it may be involved in insulin's mechanism of action. We have therefore examined vanadium levels in kidney, muscle, and liver tissues from normal and diabetic BB Wistar rats. Our results indicate that diabetes mellitus can decrease the tissue vanadium content of liver, suggesting that the trace element vanadium may be important in insulin action.

  8. Emergent material properties of developing epithelial tissues.

    Science.gov (United States)

    Machado, Pedro F; Duque, Julia; Étienne, Jocelyn; Martinez-Arias, Alfonso; Blanchard, Guy B; Gorfinkiel, Nicole

    2015-11-23

    Force generation and the material properties of cells and tissues are central to morphogenesis but remain difficult to measure in vivo. Insight is often limited to the ratios of mechanical properties obtained through disruptive manipulation, and the appropriate models relating stress and strain are unknown. The Drosophila amnioserosa epithelium progressively contracts over 3 hours of dorsal closure, during which cell apices exhibit area fluctuations driven by medial myosin pulses with periods of 1.5-6 min. Linking these two timescales and understanding how pulsatile contractions drive morphogenetic movements is an urgent challenge. We present a novel framework to measure in a continuous manner the mechanical properties of epithelial cells in the natural context of a tissue undergoing morphogenesis. We show that the relationship between apicomedial myosin fluorescence intensity and strain during fluctuations is consistent with a linear behaviour, although with a lag. We thus used myosin fluorescence intensity as a proxy for active force generation and treated cells as natural experiments of mechanical response under cyclic loading, revealing unambiguous mechanical properties from the hysteresis loop relating stress to strain. Amnioserosa cells can be described as a contractile viscoelastic fluid. We show that their emergent mechanical behaviour can be described by a linear viscoelastic rheology at timescales relevant for tissue morphogenesis. For the first time, we establish relative changes in separate effective mechanical properties in vivo. Over the course of dorsal closure, the tissue solidifies and effective stiffness doubles as net contraction of the tissue commences. Combining our findings with those from previous laser ablation experiments, we show that both apicomedial and junctional stress also increase over time, with the relative increase in apicomedial stress approximately twice that of other obtained measures. Our results show that in an epithelial

  9. Infrared spectra of thyroid tumor tissues

    Science.gov (United States)

    Tolstorozhev, G. B.; Skornyakov, I. V.; Butra, V. A.

    2010-07-01

    We used infrared spectroscopy methods to study thyroid tumor tissues removed during surgery. The IR spectra of the surgical material are compared with data from histological examination. We show that in malignant neoplasms, the spectra of proteins in the region of C=O vibrations are different from the spectra of these substances in benign tumors and in tissues outside the pathological focus at a distance >1 cm from the margin of the tumor. The differences in the spectra are due to changes in the supermolecular structure of the proteins, resulting from rearrangement of the system of hydrogen bonds. We identify the spectral signs of malignant pathologies.

  10. Soft tissue sarcoma of the extremity.

    LENUS (Irish Health Repository)

    Cooper, T M

    2012-02-03

    A retrospective review of 33 cases of soft tissue sarcoma of the extremity presenting over a 10 year period was undertaken. The history, patterns of referral, diagnostic investigations, procedures undertaken and outcomes were studied. We found there was a frequent delay in diagnosis and sometimes misinterpretation of biopsy specimens. Patients were seen by a variety of specialists from disciplines such as general surgery, plastic surgery, orthopaedic surgery and rheumatology. Considerable progress has been made in the treatment of soft tissue sarcomas, often allowing local control of the tumour without amputation. We believe there should be early referral of patients having these tumours to a centre where a combined multidisciplinary approach can be undertaken.

  11. Linezolid penetration into osteo-articular tissues.

    Science.gov (United States)

    Rana, B; Butcher, I; Grigoris, P; Murnaghan, C; Seaton, R A; Tobin, C M

    2002-11-01

    Penetration of linezolid into osteo-articular tissue and fluid was studied in 10 patients undergoing primary total knee replacement. Linezolid 600 mg 12 hourly was given orally over the 48 h before operation and intravenously 1 h before induction of anaesthesia. Mean concentrations of linezolid at 90 min after the final dose, in serum, synovial fluid, synovium, muscle and cancellous bone, assayed by HPLC, were at least twice the MIC(90) for staphylococci and streptococci. The concentrations obtained indicate good penetration of this antibiotic and support its use in the management of multidrug-resistant Gram-positive bone, joint and deep-seated soft-tissue infections.

  12. Practical experience in post-mortem tissue donation in consideration of the European tissue law.

    Science.gov (United States)

    Karbe, Thomas; Braun, Christian; Wulff, Birgit; Schröder, Ann Sophie; Püschel, Klaus; Bratzke, Hansjürgen; Parzeller, Markus

    2010-03-01

    In consequence of the European guidelines of safety and quality standards for the donation, retrieval, storing and distribution of human tissues and cells the purpose of tissue transplantation was implemented into German legislation in May 2007. The law came into effect on August 1st 2007 considering of the European rules. The Institutes for Legal Medicine of the University of Frankfurt/Main and the University Medical Center Hamburg-Eppendorf developed a model for tissue retrieval. The Institute of Legal Medicine (I.f.R.) at the University Medical Center Hamburg cooperates with the German Institute of Cell and Tissue Replacement (Deutsches Institut für Zell--und Gewebeersatz DIZG). Potential post-mortem tissue donors (PMTD) among the deceased are selected by standardized sets of defined criteria. The procedure is guided by the intended exclusion criteria of the tissue regulation draft (German Transplant Law TPG GewV) in accordance with the European Guideline (2006/17/EC). Following the identification of the donor and subsequent removal of tissue, the retrieved samples were sent to the DIZG, a non-profit tissue bank according to the tissue regulation. Here the final processing into transplantable tissue grafts takes place, which then results in the allocation of tissue to hospitals in Germany and other European countries. The Center of Legal Medicine at the Johann Wolfgang Goethe-University Medical Center Frankfurt/Main cooperates since 2000 with Tutogen, a pharmaceutical company. Harvesting of musculoskeletal tissues follows corresponding regulations. To verify the outcome of PMTD at the I.f.R. Hamburg, two-statistic analysis over 12 and 4 months have been implemented. Our results have shown an increasing number of potential appropriate PMTD within the second inquiry interval but a relatively small and unvaryingly rate of successful post-mortem tissue retrievals similar to the first examination period. Thus, the aim of the model developed by the I.f.R. is to

  13. Functional attachment of soft tissues to bone: development, healing, and tissue engineering.

    Science.gov (United States)

    Lu, Helen H; Thomopoulos, Stavros

    2013-01-01

    Connective tissues such as tendons or ligaments attach to bone across a multitissue interface with spatial gradients in composition, structure, and mechanical properties. These gradients minimize stress concentrations and mediate load transfer between the soft and hard tissues. Given the high incidence of tendon and ligament injuries and the lack of integrative solutions for their repair, interface regeneration remains a significant clinical challenge. This review begins with a description of the developmental processes and the resultant structure-function relationships that translate into the functional grading necessary for stress transfer between soft tissue and bone. It then discusses the interface healing response, with a focus on the influence of mechanical loading and the role of cell-cell interactions. The review continues with a description of current efforts in interface tissue engineering, highlighting key strategies for the regeneration of the soft tissue-to-bone interface, and concludes with a summary of challenges and future directions.

  14. Growth versus metabolic tissue replacement in mouse tissues determined by stable carbon and nitrogen isotope analysis

    Science.gov (United States)

    Macavoy, S. E.; Jamil, T.; Macko, S. A.; Arneson, L. S.

    2003-12-01

    Stable isotope analysis is becoming an extensively used tool in animal ecology. The isotopes most commonly used for analysis in terrestrial systems are those of carbon and nitrogen, due to differential carbon fractionation in C3 and C4 plants, and the approximately 3‰ enrichment in 15N per trophic level. Although isotope signatures in animal tissues presumably reflect the local food web, analysis is often complicated by differential nutrient routing and fractionation by tissues, and by the possibility that large organisms are not in isotopic equilibrium with the foods available in their immediate environment. Additionally, the rate at which organisms incorporate the isotope signature of a food through both growth and metabolic tissue replacement is largely unknown. In this study we have assessed the rate of carbon and nitrogen isotopic turnover in liver, muscle and blood in mice following a diet change. By determining growth rates, we were able to determine the proportion of tissue turnover caused by growth versus that caused by metabolic tissue replacement. Growth was found to account for approximately 10% of observed tissue turnover in sexually mature mice (Mus musculus). Blood carbon was found to have the shortest half-life (16.9 days), followed by muscle (24.7 days). Liver carbon turnover was not as well described by the exponential decay equations as other tissues. However, substantial liver carbon turnover was observed by the 28th day after diet switch. Surprisingly, these tissues primarily reflect the carbon signature of the protein, rather than carbohydrate, source in their diet. The nitrogen signature in all tissues was enriched by 3 - 5‰ over their dietary protein source, depending on tissue type, and the isotopic turnover rates were comparable to those observed in carbon.

  15. The interplay between tissue growth and scaffold degradation in engineered tissue constructs

    KAUST Repository

    O’Dea, R. D.

    2012-09-18

    In vitro tissue engineering is emerging as a potential tool to meet the high demand for replacement tissue, caused by the increased incidence of tissue degeneration and damage. A key challenge in this field is ensuring that the mechanical properties of the engineered tissue are appropriate for the in vivo environment. Achieving this goal will require detailed understanding of the interplay between cell proliferation, extracellular matrix (ECM) deposition and scaffold degradation. In this paper, we use a mathematical model (based upon a multiphase continuum framework) to investigate the interplay between tissue growth and scaffold degradation during tissue construct evolution in vitro. Our model accommodates a cell population and culture medium, modelled as viscous fluids, together with a porous scaffold and ECM deposited by the cells, represented as rigid porous materials. We focus on tissue growth within a perfusion bioreactor system, and investigate how the predicted tissue composition is altered under the influence of (1) differential interactions between cells and the supporting scaffold and their associated ECM, (2) scaffold degradation, and (3) mechanotransduction-regulated cell proliferation and ECM deposition. Numerical simulation of the model equations reveals that scaffold heterogeneity typical of that obtained from μCT scans of tissue engineering scaffolds can lead to significant variation in the flow-induced mechanical stimuli experienced by cells seeded in the scaffold. This leads to strong heterogeneity in the deposition of ECM. Furthermore, preferential adherence of cells to the ECM in favour of the artificial scaffold appears to have no significant influence on the eventual construct composition; adherence of cells to these supporting structures does, however, lead to cell and ECM distributions which mimic and exaggerate the heterogeneity of the underlying scaffold. Such phenomena have important ramifications for the mechanical integrity of

  16. Multiphasic Scaffolds for Periodontal Tissue Engineering

    Science.gov (United States)

    Ivanovski, S.; Vaquette, C.; Gronthos, S.; Hutmacher, D.W.; Bartold, P.M.

    2014-01-01

    For a successful clinical outcome, periodontal regeneration requires the coordinated response of multiple soft and hard tissues (periodontal ligament, gingiva, cementum, and bone) during the wound-healing process. Tissue-engineered constructs for regeneration of the periodontium must be of a complex 3-dimensional shape and adequate size and demonstrate biomechanical stability over time. A critical requirement is the ability to promote the formation of functional periodontal attachment between regenerated alveolar bone, and newly formed cementum on the root surface. This review outlines the current advances in multiphasic scaffold fabrication and how these scaffolds can be combined with cell- and growth factor–based approaches to form tissue-engineered constructs capable of recapitulating the complex temporal and spatial wound-healing events that will lead to predictable periodontal regeneration. This can be achieved through a variety of approaches, with promising strategies characterized by the use of scaffolds that can deliver and stabilize cells capable of cementogenesis onto the root surface, provide biomechanical cues that encourage perpendicular alignment of periodontal fibers to the root surface, and provide osteogenic cues and appropriate space to facilitate bone regeneration. Progress on the development of multiphasic constructs for periodontal tissue engineering is in the early stages of development, and these constructs need to be tested in large animal models and, ultimately, human clinical trials. PMID:25139362

  17. Tracheostomy Decannulation: Suprastomal Granulation Tissue in ...

    African Journals Online (AJOL)

    Background: Suprastomal granulation tissue is a complication of tracheostomy which may make decannulation difficult and presents a therapeutic challenge to the Otorhinolaryngologists. The aims of this study therefore were to evaluate tracheostomy in black African population, determine the prevalence of suprastomal ...

  18. Fundamentals of bladder tissue engineering | Mahfouz | African ...

    African Journals Online (AJOL)

    Tissue engineering relies upon three essential pillars; the scaffold, the cells seeded on scaffolds and lastly the environmental conditions, including growth factors, cytokines and extracellular matrix (ECM) which promote angiogenesis and neurogenesis of the regenerated organs. The choice of the scaffold and the type of ...

  19. Adipose Tissue Dysfunction in Nascent Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Andrew A. Bremer

    2013-01-01

    Full Text Available The metabolic syndrome (MetS confers an increased risk for both type 2 diabetes mellitus (T2DM and cardiovascular disease (CVD. Moreover, studies on adipose tissue biology in nascent MetS uncomplicated by T2DM and/or CVD are scanty. Recently, we demonstrated that adipose tissue dysregulation and aberrant adipokine secretion contribute towards the syndrome’s low-grade chronic proinflammatory state and insulin resistance. Specifically, we have made the novel observation that subcutaneous adipose tissue (SAT in subjects with nascent MetS has increased macrophage recruitment with cardinal crown-like structures. We have also shown that subjects with nascent MetS have increased the levels of SAT-secreted adipokines (IL-1, IL-6, IL-8, leptin, RBP-4, CRP, SAA, PAI-1, MCP-1, and chemerin and plasma adipokines (IL-1, IL-6, leptin, RBP-4, CRP, SAA, and chemerin, as well as decreased levels of plasma adiponectin and both plasma and SAT omentin-1. The majority of these abnormalities persisted following correction for increased adiposity. Our data, as well as data from other investigators, thus, highlight the importance of subcutaneous adipose tissue dysfunction in subjects with MetS and its contribution to the proinflammatory state and insulin resistance. This adipokine profile may contribute to increased insulin resistance and low-grade inflammation, promoting the increased risk of T2DM and CVD.

  20. Insulin resistance causes inflammation in adipose tissue.

    Science.gov (United States)

    Shimobayashi, Mitsugu; Albert, Verena; Woelnerhanssen, Bettina; Frei, Irina C; Weissenberger, Diana; Meyer-Gerspach, Anne Christin; Clement, Nicolas; Moes, Suzette; Colombi, Marco; Meier, Jerome A; Swierczynska, Marta M; Jenö, Paul; Beglinger, Christoph; Peterli, Ralph; Hall, Michael N

    2018-03-12

    Obesity is a major risk factor for insulin resistance and type 2 diabetes. In adipose tissue, obesity-mediated insulin resistance correlates with the accumulation of proinflammatory macrophages and inflammation. However, the causal relationship of these events is unclear. Here, we report that obesity-induced insulin resistance in mice precedes macrophage accumulation and inflammation in adipose tissue. Using a mouse model that combines genetically induced, adipose-specific insulin resistance (mTORC2-knockout) and diet-induced obesity, we found that insulin resistance causes local accumulation of proinflammatory macrophages. Mechanistically, insulin resistance in adipocytes results in production of the chemokine monocyte chemoattractant protein 1 (MCP1), which recruits monocytes and activates proinflammatory macrophages. Finally, insulin resistance (high homeostatic model assessment of insulin resistance [HOMA-IR]) correlated with reduced insulin/mTORC2 signaling and elevated MCP1 production in visceral adipose tissue from obese human subjects. Our findings suggest that insulin resistance in adipose tissue leads to inflammation rather than vice versa.

  1. Cardio-adipose tissue cross-talk

    DEFF Research Database (Denmark)

    Lindberg, Søren; Jensen, Jan Skov; Bjerre, Mette

    2014-01-01

    increases adiponectin secretion, indicating that NPs may improve adipose tissue function and in this way function as a cardio-protective agent in HF. Accordingly we investigated the interplay between plasma adiponectin, plasma proBNP, and development of HF. METHODS AND RESULTS: We prospectively followed...

  2. The sensitivity of biological tissue to ultrasound.

    Science.gov (United States)

    Barnett, S B; Rott, H D; ter Haar, G R; Ziskin, M C; Maeda, K

    1997-01-01

    Mammalian tissues have differing sensitivities to damage by physical agents such as ultrasound. This article evaluates the scientific data in terms of known physical mechanisms of interaction and the impact on pre- and postnatal tissues. Actively dividing cells of the embryonic and fetal central nervous system are most readily disturbed. As a diagnostic ultrasound beam envelopes a small volume of tissue, it is possible that the effects of mild disturbance may not be detected unless major neural pathways are involved. There is evidence that ultrasound can be detected by the central nervous system; however, this does not necessarily imply that the bioeffect is hazardous to the fetus. Biologically significant temperature increases can occur at or near to bone in the fetus from the second trimester, if the beam is held stationary for more than 30 s in some pulsed Doppler applications. In this way, sensory organs that are encased in bone may be susceptible to heating by conduction. Reports in animals and humans of retarded growth and development following frequent exposures to diagnostic ultrasound, in the absence of significant heating, are difficult to explain from the current knowledge of ultrasound mechanisms. There is no evidence of cavitation effects occurring in the soft tissues of the fetus when exposed to diagnostic ultrasound; however, the possibility exists that such effects may be enhanced by the introduction of echo-contrast agents.

  3. Reparative inflammation takes charge of tissue regeneration

    NARCIS (Netherlands)

    Karin, Michael; Clevers, Hans

    2016-01-01

    Inflammation underlies many chronic and degenerative diseases, but it also mitigates infections, clears damaged cells and initiates tissue repair. Many of the mechanisms that link inflammation to damage repair and regeneration in mammals are conserved in lower organisms, indicating that it is an

  4. Immunoglobulin for necrotising soft tissue infections (INSTINCT)

    DEFF Research Database (Denmark)

    Madsen, Martin Bruun; Lange, Theis; Hjortrup, Peter Buhl

    2016-01-01

    INTRODUCTION: Necrotising soft tissue infections (NSTI) are aggressive infections that can result in severe disability or death. Intravenous polyspecific immunoglobulin G (IVIG) is used as supplementary treatment for patients with NSTIs. The level of evidence is very low, but suggests that IVIG may...

  5. Tissue expansion in burn sequelae repair.

    Science.gov (United States)

    Tavares Filho, João Medeiros; Belerique, Manoel; Franco, Diogo; Porchat, Carlos Alberto; Franco, Talita

    2007-03-01

    Burns may cause emotional, aesthetic and functional sequelae. Extended or hypertrophic scars are usually difficult to repair using local tissues, and the use of skin grafts may cause further injuries to the donor sites. The use of tissue expanders may offer a better option in the treatment of burn sequelae. This is a report on our experience using tissue expanders in 54 cases (23 patients) of burn sequelae located in different anatomical areas. Fourteen of the patients were female and nine male ranging in age between 5 and 48. The expanders were placed in the subgaleal, submuscular, subfascial or subcutaneous planes. Skin expansion was completed in 50 cases (92.5%). The injured area was removed by advancement flaps in 44 cases and by transposition flaps in 6 of them. Primary expansion was performed in 42 cases and reexpansion in 12. The rate of complications was 24.07%, of which 30.8% were considered to be absolute and 69.2% relative. Tissue expansion is an excellent option for burn sequelae treatment because it provides skin of similar local characteristics and does not damage the donor site. The procedure can be repeated in the event of major sequelae (reexpansion).

  6. Tissue Engineering Strategies in Ligament Regeneration

    Directory of Open Access Journals (Sweden)

    Caglar Yilgor

    2012-01-01

    Full Text Available Ligaments are dense fibrous connective tissues that connect bones to other bones and their injuries are frequently encountered in the clinic. The current clinical approaches in ligament repair and regeneration are limited to autografts, as the gold standard, and allografts. Both of these techniques have their own drawbacks that limit the success in clinical setting; therefore, new strategies are being developed in order to be able to solve the current problems of ligament grafting. Tissue engineering is a novel promising technique that aims to solve these problems, by producing viable artificial ligament substitutes in the laboratory conditions with the potential of transplantation to the patients with a high success rate. Direct cell and/or growth factor injection to the defect site is another current approach aiming to enhance the repair process of the native tissue. This review summarizes the current approaches in ligament tissue engineering strategies including the use of scaffolds, their modification techniques, as well as the use of bioreactors to achieve enhanced regeneration rates, while also discussing the advances in growth factor and cell therapy applications towards obtaining enhanced ligament regeneration.

  7. Mycobacterium canettii Infection of Adipose Tissues.

    Science.gov (United States)

    Bouzid, Fériel; Brégeon, Fabienne; Poncin, Isabelle; Weber, Pascal; Drancourt, Michel; Canaan, Stéphane

    2017-01-01

    Adipose tissues were shown to host Mycobacterium tuberculosis which is persisting inside mature adipocytes. It remains unknown whether this holds true for Mycobacterium canettii , a rare representative of the M. tuberculosis complex responsible for lymphatic and pulmonary tuberculosis. Here, we infected primary murine white and brown pre-adipocytes and murine 3T3-L1 pre-adipocytes and mature adipocytes with M. canettii and M. tuberculosis as a positive control. Both mycobacteria were able to infect 18-22% of challenged primary murine pre-adipocytes; and to replicate within these cells during a 7-day experiment with the intracellular inoculums being significantly higher in brown than in white pre-adipocytes for M. canettii ( p = 0.02) and M. tuberculosis ( p = 0.03). Further in-vitro infection of 3T3-L1 mature adipocytes yielded 9% of infected cells by M. canettii and 17% of infected cells by M. tuberculosis ( p = 0.001). Interestingly, M. canettii replicated and accumulated intra-cytosolic lipid inclusions within mature adipocytes over a 12-day experiment; while M. tuberculosis stopped replicating at day 3 post-infection. These results indicate that brown pre-adipocytes could be one of the potential targets for M. tuberculosis complex mycobacteria; and illustrate differential outcome of M. tuberculosis complex mycobacteria into adipose tissues. While white adipose tissue is an unlikely sanctuary for M. canettii , it is still an open question whether M. canettii and M. tuberculosis could persist in brown adipose tissues.

  8. Cell Source for Tissue and Organ Printing

    Science.gov (United States)

    Xu, Tao; Yuan, Yuyu; Yoo, James J.

    Organ printing, a novel approach in tissue engineering, applies computer-driven deposition of cells, growth factors, biomaterials layer-by-layer to create complex 3D tissue or organ constructs. This emerging technology shows great promise in regenerative medicine, because it may help to address current crisis of tissue and organ shortage for transplantation. Organ printing is developing fast, and there are exciting new possibilities in this area. Successful cell and organ printing requires many key elements. Among these, the choice of appropriate cells for printing is vital. This chapter surveys available cell sources for cell and organ printing application and discusses factors that affect cell choice. Special emphasis is put on several important factors, including the proposed printing system and bioprinters, the assembling method, and the target tissues or organs, which need to be considered to select proper cell sources and cell types. In this chapter, characterizations of the selected cells to justify and/or refine the cell selection will also be discussed. Finally, future prospects in this field will be envisioned.

  9. Hype and expectations in tissue engineering

    NARCIS (Netherlands)

    Oerlemans, A.J.M.; Hoek, M.E. van; Leeuwen, E. van; Dekkers, W.J.M.

    2014-01-01

    Scientific progress and the development of new technologies often incite enthusiasm, both in scientists and the public at large, and this is especially apparent in discussions of emerging medical technologies, such as tissue engineering (TE). Future-oriented narratives typically discuss potential

  10. Substituted Indoleacetic Acids Tested in Tissue Cultures

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1978-01-01

    Monochloro substituted IAA inhibited shoot induction in tobacco tissue cultures about as much as IAA. Dichloro substituted IAA inhibited shoot formation less. Other substituted IAA except 5-fluoro- and 5-bromoindole-3-acetic acid were less active than IAA. Callus growth was quite variable...

  11. Substituted Indoleacetic Acids Tested in Tissue Cultures

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1978-01-01

    Monochloro substituted IAA inhibited shoot induction in tobacco tissue cultures about as much as IAA. Dichloro substituted IAA inhibited shoot formation less. Other substituted IAA except 5-fluoro- and 5-bromoindole-3-acetic acid were less active than IAA. Callus growth was quite variable and not...... and not correlated with auxin strength measured in the Avena coleoptile test....

  12. Does bariatric surgery improve adipose tissue function?

    Science.gov (United States)

    Frikke-Schmidt, H.; O’Rourke, R. W.; Lumeng, C. N.; Sandoval, D. A.; Seeley, R. J.

    2017-01-01

    Summary Bariatric surgery is currently the most effective treatment for obesity. Not only do these types of surgeries produce significant weight loss but also they improve insulin sensitivity and whole body metabolic function. The aim of this review is to explore how altered physiology of adipose tissue may contribute to the potent metabolic effects of some of these procedures. This includes specific effects on various fat depots, the function of individual adipocytes and the interaction between adipose tissue and other key metabolic tissues. Besides a dramatic loss of fat mass, bariatric surgery shifts the distribution of fat from visceral to the subcutaneous compartment favoring metabolic improvement. The sensitivity towards lipolysis controlled by insulin and catecholamines is improved, adipokine secretion is altered and local adipose inflammation as well as systemic inflammatory markers decreases. Some of these changes have been shown to be weight loss independent, and novel hypothesis for these effects includes include changes in bile acid metabolism, gut microbiota and central regulation of metabolism. In conclusion bariatric surgery is capable of improving aspects of adipose tissue function and do so in some cases in ways that are not entirely explained by the potent effect of surgery. PMID:27272117

  13. Metabolic regulation of macrophages in tissues

    NARCIS (Netherlands)

    van den Bossche, Jan; Saraber, Doina L.

    2018-01-01

    Macrophages are innate immune cells that provide host defense and have tissue-specific roles in the maintenance of organ homeostasis and integrity. In most cases macrophages keep us healthy but when their balanced response to damage or homeostatic signals is perturbed, they can drive chronic

  14. Autonomous informational stability in connective tissues.

    Science.gov (United States)

    Brand, R A

    1992-02-01

    No coherent theories currently explain connective tissue stability (i.e. 'memory') as well as spatial and temporal adaptability in the face of continual flux of its constituents. Furthermore, explanations of stability based exclusively upon DNA raise certain inherent problems, particularly with the spatial concordance of somatic tissues. As an alternative explanation, it is hypothesized that while connective tissue cells produce extracellular protein precursors through DNA-dependent processes, the assembly, location, orientation and configuration of the extracellular macromolecules as well as their degree of cell attachment depend primarily upon local micro-environmental conditions and/or self-organization rather than strictly cellular processes. The resulting extracellular matrix (ECM) serves as a time- and spatially-variable filter about each cell to afford a relatively consistent micro-environment for all similar cells, regardless of the more variable macro-environment. By insuring a consistent set of signals to the cell, the filter provides a non-genetic memory complementary to genetic memory. The half-lives of constituent molecules define the duration of the filter, allowing the filter to adapt to new environmental demands, yet to maintain a consistent milieu for the cell. The cell/matrix construct permits local, self-optimizing, non-deterministic tissue autonomy obviating the need to postulate certain intricate mechanisms coordinating spatial morphology and temporal behavior.

  15. ALTERED MORPHOLOGY OF LIVER AND PANCREAS TISSUES ...

    African Journals Online (AJOL)

    Summary: The effects of food processing and or cooking practices in the variations in morphological changes in tissues were investigated. ... on a wire gauze without treatment with spices or cured. It was then roasted with charcoal fire on .... processes and functional additives on the. Nitrosamine Level in Meat. Linus Pauling.

  16. Biomaterials and tissue engineering in reconstructive surgery

    Indian Academy of Sciences (India)

    In spite of some good successes and excellent materials, there are still serious limitations to the performance of implants today, and the paper explains these limitations and develops this theme in order to describe the recent innovations in tissue engineering, which involves a different approach to reconstruction of the body.

  17. New trends in spinal cord tissue engineering

    Czech Academy of Sciences Publication Activity Database

    Kubinová, Šárka

    2015-01-01

    Roč. 10, č. 2 (2015), s. 129-145 ISSN 1479-6708 R&D Projects: GA MŠk(CZ) LO1309 Institutional support: RVO:68378041 Keywords : biomaterial * cell therapy * regenerative medicine * spinal cord injury * stem cells scaffold * tissue engineering Subject RIV: FH - Neurology

  18. Browning and thermogenic programing of adipose tissue.

    Science.gov (United States)

    Kiefer, Florian W

    2016-08-01

    The view of adipose tissue as solely a fat storing organ has changed significantly over the past two decades with the discoveries of numerous adipocyte-secreted factors, so called adipokines, and their endocrine functions throughout the body. The newest chapter added to this story is the finding that adipose tissue is also a thermogenic organ contributing to energy expenditure through actions of specialized, heat-producing brown or beige adipocytes. In contrast to bone fide brown adipocytes, beige cells develop within white fat depots in response to various stimuli such as prolonged cold exposure, underscoring the great thermogenic plasticity of adipose tissue. The energy dissipating properties of beige and/or brown adipocytes hold great promise as a novel therapeutic concept against obesity and related complications. Hence, identifying the specific thermogenic adipocyte populations in humans and their pathways of activation are key milestones of current metabolism research. Here we will discuss the recent advances in the understanding of the molecular and physiological mechanisms of adipose tissue browning. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Fat tissue, aging, and cellular senescence.

    NARCIS (Netherlands)

    Tchkonia, T.; Morbeck, D.E.; Zglinicki, T. von; Deursen, J.M.A. van; Lustgarten, J.; Scrable, H.; Khosla, S.; Jensen, M.D.; Kirkland, J.L.

    2010-01-01

    Fat tissue, frequently the largest organ in humans, is at the nexus of mechanisms involved in longevity and age-related metabolic dysfunction. Fat distribution and function change dramatically throughout life. Obesity is associated with accelerated onset of diseases common in old age, while fat

  20. Guanase in reticulocytes and other rat tissues

    Energy Technology Data Exchange (ETDEWEB)

    Hindman, H.B.; Knox, W.E.

    1978-01-01

    A sensitive and precise assay of guanase was based on the conversion of /sup 14/C-guanine to uric acid in the presence of excess xanthine oxidase. The enzyme was entirely soluble in rat tissues and no inhibitors of it were detected. The most active tissues were red blood cells, lung and lactating mammary gland, with more than twice the activity of liver. The contained blood could account for the low activity in adult skeletal muscle and some other tissues. All fetal tissues examined were without activity. Activity in mammary gland rose fourfold during lactation and dropped precipitously during involution, with a secondary rise associated in time with the loss of cells from the gland. Reticulocytes present normally and after hemorrhagic anemia appeared to account for substantially all of the high guanase activity in red blood cells. The guanase level could be used to predict the degree of reticulocytosis in rats within confidence limits of +- 0.2%. The virtual absence of guanase in human red cells was confirmed, even in bloods containing elevated reticulocyte numbers.

  1. Olaratumab for advanced soft tissue sarcoma.

    Science.gov (United States)

    Tobias, Alexander; O'brien, Michael P; Agulnik, Mark

    2017-07-01

    Olaratumab is a humanized IgG1 monoclonal antibody that blocks the platelet-derived growth factor receptor alpha (PDGFRα). Its antagonistic behavior inhibits the receptor's tyrosine kinase activity, thereby, turning off the downstream signaling cascades responsible for soft tissue sarcoma tumorigenesis. In October 2016, olaratumab received Food and Drug Administration (FDA) approval for its use in combination with doxorubicin for treatment of advanced soft tissue sarcoma. Areas covered: This drug profile takes a comprehensive look at the clinical studies leading to FDA approval of olaratumab as well as its safety and efficacy as a front-line treatment option for sarcoma patients. The literature search was primarily conducted using PubMed. Expert commentary: The combination of olaratumab plus doxorubicin has provided a new front-line therapeutic option for soft tissue sarcoma patients. An open-label phase Ib and randomized phase II trial in patients with advanced soft tissue sarcoma demonstrated that the addition of olaratumab to doxorubicin prolonged progression-free survival by 2.5 months and overall survival by 11.8 months when compared to doxorubicin alone. Of importance, this clinically meaningful increase in overall survival did not come at the expense of a significantly greater number of toxicities. A phase III confirmatory trial (ClinicalTrials.gov Identifier NCT02451943) will be completed in 2020.

  2. Facial soft tissue changes after orthodontic treatment

    African Journals Online (AJOL)

    2013-09-09

    Sep 9, 2013 ... Conclusion: There were significant changes in facial soft tissue esthetics after orthodontic treatment for class II and. III cases. ... Departments of Orthodontics, Faculty of Dentistry, Bezmialem Vakif University, Istanbul, 1Mevlana University, Konya ,Turkey. Access this ..... after functional appliance treatment.

  3. MRI evaluation of soft tissue hydatid disease

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Diez, A.I.; Ros Mendoza, L.H.; Villacampa, V.M.; Cozar, M.; Fuertes, M.I. [Dept. of Radiology, Hospital Miguel Servet, Zaragoza (Spain)

    2000-03-01

    Infestation in soft tissue by Echinococcus granulosus is not a common disease, and its diagnosis is based on clinical, laboratory data and radiological findings. The aim of our retrospective study is to give an overview of the different signs and patterns shown by MRI that can be useful in characterizing soft tissue hydatid disease. The MRI images obtained in seven patients with soft tissue and subcutaneous hydatidosis were reviewed. Typical signs of hydatidosis were multivesicular lesions with or without hypointense peripheral ring (''rim sign''). Related to the presence and absence, respectively, of viable scolices in the microscopic exam, daughter cysts were presented either as high signal intensity or low signal intensity on T2-weighted images. Low-intensity detached layers within the cyst and peripheral enhancement with gadolinium-DTPA were also presented. Atypical signs were presented in an infected muscular cyst, a subcutaneous unilocular cyst and several unilocular cysts. Knowledge of the different patterns in MRI of soft tissue hydatid disease can be useful in diagnosing this entity. We observed that the ''rim sign'' is not as common as in other locations, and in addition, MRI seems to be of assistance when evaluating the vitality of the cysts. (orig.)

  4. Histopathology of Tilapia tissues harbouring Clinostomum tilapiae ...

    African Journals Online (AJOL)

    Tissues obtained from infected Oreochromis niloticus were processed sectioned and stained with haemotoxylin and eosin. Good sections were selected, studied and photographed. The histopathology revealed a proliferation of eosinophiles at the secondary lamellar of the gills. The site of attachment on the fish skin ...

  5. Localization of inorganic ions in plant tissues

    International Nuclear Information System (INIS)

    Iren, F. van.

    1980-01-01

    The author has been unable to devise a generally applicable technique of ion localization in cells and tissues. He concludes that ion localization in living organisms remains difficult. From this study, a rough outline of how ions are transported into, through, and out of plant roots is drawn. (Auth.)

  6. Principles of Tissue Engineering for Food

    NARCIS (Netherlands)

    Post, M.; Weele, van der Cor

    2014-01-01

    The technology required for tissue-engineering food is the same as for medical applications, and in fact is derived from it. There are major differences in the implementation of those technologies, primarily related to the enormous scale required for food production and the different economical

  7. Biomarkers of necrotising soft tissue infections

    DEFF Research Database (Denmark)

    Hansen, Marco Bo; Simonsen, Ulf; Garred, Peter

    2015-01-01

    INTRODUCTION: The mortality and amputation rates are still high in patients with necrotising soft tissue infections (NSTIs). It would be ideal to have a set of biomarkers that enables the clinician to identify high-risk patients with NSTI on admission. The objectives of this study are to evaluate...

  8. Soft Tissue Wounds and Principles of Healing

    Science.gov (United States)

    2007-01-01

    povidine-iodine should be discontinued because it is tissue toxic. Better alternatives include nonionic detergents or chlorinated tap water [34]. The goal is...Dermatol Clin 1998;16(1):25–47. [65] SmackDP,HarringtonAC,DunnC, et al. Infection and allergy incidence in ambulatory sur- gery patients using white

  9. Connective Tissue Disease in a Malawian Man

    African Journals Online (AJOL)

    31Ward Round 2. Introduction. We describe a case of systemic connective tissue disease (CTD) in a Malawian man in whom an autoimmune etiology was likely. Autoimmune CTDs ... Case Presentantion. A 17 year-old student was referred to Queen Elizabeth ... X rays of the hands are shown in Figure 2. The most striking.

  10. Tissue thyroid hormone levels in critical illness

    NARCIS (Netherlands)

    R.P. Peeters (Robin); S.D. van Geyten (Serge Der); P.J. Wouters (Pieter); V.M. Darras (Veerle); H. van Toor (Hans); E. Kaptein (Ellen); T.J. Visser (Theo); G. van den Berghe (Greet)

    2005-01-01

    textabstractContext: Pronounced alterations in serum thyroid hormone levels occur during critical illness. T3 decreases and rT3 increases, the magnitudes of which are related to the severity of disease. It is unclear whether these changes are associated with decreased tissue T3 concentrations and,

  11. Cell–scaffold interaction within engineered tissue

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Haiping; Liu, Yuanyuan, E-mail: Yuanyuan_liu@shu.edu.cn; Jiang, Zhenglong; Chen, Weihua; Yu, Yongzhe; Hu, Qingxi

    2014-05-01

    The structure of a tissue engineering scaffold plays an important role in modulating tissue growth. A novel gelatin–chitosan (Gel–Cs) scaffold with a unique structure produced by three-dimensional printing (3DP) technology combining with vacuum freeze-drying has been developed for tissue-engineering applications. The scaffold composed of overall construction, micro-pore, surface morphology, and effective mechanical property. Such a structure meets the essential design criteria of an ideal engineered scaffold. The favorable cell–matrix interaction supports the active biocompatibility of the structure. The structure is capable of supporting cell attachment and proliferation. Cells seeded into this structure tend to maintain phenotypic shape and secreted large amounts of extracellular matrix (ECM) and the cell growth decreased the mechanical properties of scaffold. This novel biodegradable scaffold has potential applications for tissue engineering based upon its unique structure, which acts to support cell growth. - Highlights: • The scaffold is not only for providing a surface for cell residence but also for determining cell phenotype and retaining structural integrity. • The mechanical property of scaffold can be affected by activities of cell. • The scaffold provides a microenvironment for cell attachment, growth, and migration.

  12. The endocrine function of adipose tissue

    Directory of Open Access Journals (Sweden)

    Wagner de Jesus Pinto

    2014-09-01

    Full Text Available Currently it is considered the adipose tissue as a dynamic structure involved in many physiological and metabolic processes, produces and releases a variety of active peptides known by the generic name of adipokines that act performing endocrine, paracrine and autocrine. Furthermore, numbers expressed receptors that respond allows the afferent signals from endocrine organs, and also central nervous system. In 1987, the adipose tissue has been identified as the major site of metabolism of steroid hormones, thereafter, in 1994, it was recognized as an endocrine organ and the leptin being an early secretory products identified. In addition other biologically active substances were being isolated, such as adiponectin, resistin, TNF-a, interleukin-6 and others. The adipokines derived from adipose tissue modulate many metabolic parameters such as control of food intake, energy balance and peripheral insulin sensitivity, for example. Thus, the altered secretion of adipokines by adipose tissue may have metabolic effects may present complex relations with the pathophysiological process of obesity, endothelial dysfunction, inflammation, atherosclerosis and Diabetes mellitus. The understanding of the molecular processes occurring in the adipocytes may provide new tools for the treatment of pathophysiological conditions such as, for example, metabolic syndrome, obesity and diabetes mellitus.

  13. Effects of pions on normal tissues

    International Nuclear Information System (INIS)

    Tokita, N.

    1981-01-01

    Verification of the uniform biological effectiveness of pion beams of various dimensions produced at LAMPF has been made using cultured mammalian cells and mouse jejunum. Normal tissue radiobiology studies at LAMPF are reviewed with regard to biological beam characterization for the therapy program and the current status of acute and late effect studies on rodents

  14. Plasma acylcarnitines inadequately reflect tissue acylcarnitine metabolism

    NARCIS (Netherlands)

    Schooneman, Marieke G.; Achterkamp, Niki; Argmann, Carmen A.; Soeters, Maarten R.; Houten, Sander M.

    2014-01-01

    Acylcarnitines have been linked to obesity-induced insulin resistance. However the majority of these studies have focused on acylcarnitines in plasma. It is currently unclear to what extent plasma levels of acylcarnitines reflect tissue acylcarnitine metabolism. We investigated the correlation of

  15. Rapid development of tissue bank achieved by International Atomic Energy Agency (IAEA) Tissue Banking Programme in China.

    Science.gov (United States)

    Zhang, Yu-Min; Wang, Jian-Ru; Zhang, Nai-Li; Liu, Xiao-Ming; Zhou, Mo; Ma, Shao-Ying; Yang, Ting; Li, Bao-Xing

    2014-09-01

    Before 1986, the development of tissue banking in China has been slow and relatively uncoordinated. Under the support of International Atomic Energy Agency (IAEA), Tissue Banking in China experienced rapid development. In this period, China Institute for Radiation Protection tissue bank mastered systematic and modern tissue banking technique by IAEA training course and gradually developed the first regional tissue bank (Shanxi Provincial Tissue Bank, SPTB) to provide tissue allograft. Benefit from training course, SPTB promoted the development of tissue transplantation by ways of training, brochure, advertisement and meeting. Tissue allograft transplantation acquired recognition from clinic and supervision and administration from government. Quality system gradually is developing and perfecting. Tissue allograft transplantation and tissue bank are developing rapidly and healthy.

  16. Evaluation of thyroid tissue by Raman spectroscopy

    Science.gov (United States)

    Teixeira, C. S. B.; Bitar, R. A.; Santos, A. B. O.; Kulcsar, M. A. V.; Friguglietti, C. U. M.; Martinho, H. S.; da Costa, R. B.; Martin, A. A.

    2010-02-01

    Thyroid gland is a small gland in the neck consisting of two lobes connected by an isthmus. Thyroid's main function is to produce the hormones thyroxine (T4), triiodothyronine (T3) and calcitonin. Thyroid disorders can disturb the production of these hormones, which will affect numerous processes within the body such as: regulating metabolism and increasing utilization of cholesterol, fats, proteins, and carbohydrates. The gland itself can also be injured; for example, neoplasias, which have been considered the most important, causing damage of to the gland and are difficult to diagnose. There are several types of thyroid cancer: Papillary, Follicular, Medullary, and Anaplastic. The occurrence rate, in general is between 4 and 7%; which is on the increase (30%), probably due to new technology that is able to find small thyroid cancers that may not have been found previously. The most common method used for thyroid diagnoses are: anamnesis, ultrasonography, and laboratory exams (Fine Needle Aspiration Biopsy- FNAB). However, the sensitivity of those test are rather poor, with a high rate of false-negative results, therefore there is an urgent need to develop new diagnostic techniques. Raman spectroscopy has been presented as a valuable tool for cancer diagnosis in many different tissues. In this work, 27 fragments of the thyroid were collected from 18 patients, comprising the following histologic groups: goitre adjacent tissue, goitre nodular tissue, follicular adenoma, follicular carcinoma, and papillary carcinoma. Spectral collection was done with a commercial FTRaman Spectrometer (Bruker RFS100/S) using a 1064 nm laser excitation and Ge detector. Principal Component Analysis, Cluster Analysis, and Linear Discriminant Analysis with cross-validation were applied as spectral classification algorithm. Comparing the goitre adjacent tissue with the goitre nodular region, an index of 58.3% of correct classification was obtained. Between goitre (nodular region and

  17. Brown adipose tissue in cetacean blubber.

    Directory of Open Access Journals (Sweden)

    Osamu Hashimoto

    Full Text Available Brown adipose tissue (BAT plays an important role in thermoregulation in species living in cold environments, given heat can be generated from its chemical energy reserves. Here we investigate the existence of BAT in blubber in four species of delphinoid cetacean, the Pacific white-sided and bottlenose dolphins, Lagenorhynchus obliquidens and Tursiops truncates, and Dall's and harbour porpoises, Phocoenoides dalli and Phocoena phocoena. Histology revealed adipocytes with small unilocular fat droplets and a large eosinophilic cytoplasm intermingled with connective tissue in the innermost layers of blubber. Chemistry revealed a brown adipocyte-specific mitochondrial protein, uncoupling protein 1 (UCP1, within these same adipocytes, but not those distributed elsewhere throughout the blubber. Western blot analysis of extracts from the inner blubber layer confirmed that the immunohistochemical positive reaction was specific to UCP1 and that this adipose tissue was BAT. To better understand the distribution of BAT throughout the entire cetacean body, cadavers were subjected to computed tomography (CT scanning. Resulting imagery, coupled with histological corroboration of fine tissue structure, revealed adipocytes intermingled with connective tissue in the lowest layer of blubber were distributed within a thin, highly dense layer that extended the length of the body, with the exception of the rostrum, fin and fluke regions. As such, we describe BAT effectively enveloping the cetacean body. Our results suggest that delphinoid blubber could serve a role additional to those frequently attributed to it: simple insulation blanket, energy storage, hydrodynamic streamlining or contributor to positive buoyancy. We believe delphinoid BAT might also function like an electric blanket, enabling animals to frequent waters cooler than blubber as an insulator alone might otherwise allow an animal to withstand, or allow animals to maintain body temperature in cool

  18. Brown adipose tissue in cetacean blubber.

    Science.gov (United States)

    Hashimoto, Osamu; Ohtsuki, Hirofumi; Kakizaki, Takehiko; Amou, Kento; Sato, Ryo; Doi, Satoru; Kobayashi, Sara; Matsuda, Ayaka; Sugiyama, Makoto; Funaba, Masayuki; Matsuishi, Takashi; Terasawa, Fumio; Shindo, Junji; Endo, Hideki

    2015-01-01

    Brown adipose tissue (BAT) plays an important role in thermoregulation in species living in cold environments, given heat can be generated from its chemical energy reserves. Here we investigate the existence of BAT in blubber in four species of delphinoid cetacean, the Pacific white-sided and bottlenose dolphins, Lagenorhynchus obliquidens and Tursiops truncates, and Dall's and harbour porpoises, Phocoenoides dalli and Phocoena phocoena. Histology revealed adipocytes with small unilocular fat droplets and a large eosinophilic cytoplasm intermingled with connective tissue in the innermost layers of blubber. Chemistry revealed a brown adipocyte-specific mitochondrial protein, uncoupling protein 1 (UCP1), within these same adipocytes, but not those distributed elsewhere throughout the blubber. Western blot analysis of extracts from the inner blubber layer confirmed that the immunohistochemical positive reaction was specific to UCP1 and that this adipose tissue was BAT. To better understand the distribution of BAT throughout the entire cetacean body, cadavers were subjected to computed tomography (CT) scanning. Resulting imagery, coupled with histological corroboration of fine tissue structure, revealed adipocytes intermingled with connective tissue in the lowest layer of blubber were distributed within a thin, highly dense layer that extended the length of the body, with the exception of the rostrum, fin and fluke regions. As such, we describe BAT effectively enveloping the cetacean body. Our results suggest that delphinoid blubber could serve a role additional to those frequently attributed to it: simple insulation blanket, energy storage, hydrodynamic streamlining or contributor to positive buoyancy. We believe delphinoid BAT might also function like an electric blanket, enabling animals to frequent waters cooler than blubber as an insulator alone might otherwise allow an animal to withstand, or allow animals to maintain body temperature in cool waters during

  19. Biomimetic material strategies for cardiac tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Prabhakaran, Molamma P., E-mail: nnimpp@nus.edu.sg [Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore); Venugopal, J. [Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore); Kai, Dan [NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore (Singapore); Ramakrishna, Seeram [Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore)

    2011-04-08

    Cardiovascular disease precedes many serious complications including myocardial infarction (MI) and it remains a major problem for the global community. Adult mammalian heart has limited ability to regenerate and compensate for the loss of cardiomyocytes. Restoration of cardiac function by replacement of diseased myocardium with functional cardiomyocytes is an intriguing strategy because it offers a potential cure for MI. Biomaterials are fabricated in nanometer scale dimensions by combining the chemical, biological, mechanical and electrical aspects of material for potential tissue engineering (TE) applications. Synthetic polymers offer advantageous in their ability to tailor the mechanical properties, and natural polymers offer cell recognition sites necessary for cell, adhesion and proliferation. Cardiac tissue engineering (TE) aim for the development of a bioengineered construct that can provide physical support to the damaged cardiac tissue by replacing certain functions of the damaged extracellular matrix and prevent adverse cardiac remodeling and dysfunction after MI. Electrospun nanofibers are applied as heart muscle patches, while hydrogels serve as a platform for controlled delivery of growth factors, prevent mechanical complications and assist in cell recruitment. This article reviews the applications of different natural and synthetic polymeric materials utilized as cardiac patches, injectables or 3D constructs for cardiac TE. Smart organization of nanoscale assemblies with synergistic approaches of utilizing nanofibers and hydrogels could further advance the field of cardiac tissue engineering. Rapid innovations in biomedical engineering and cell biology will bring about new insights in the development of optimal scaffolds and methods to create tissue constructs with relevant contractile properties and electrical integration to replace or substitute the diseased myocardium.

  20. Effect of tenoxicam on rat liver tissue.

    Science.gov (United States)

    Karatopuk, D Ulusoy; Gökçımen, Alpaslan

    2010-06-01

    Tenoxicam is a non-steroidal antiinflammatory drug, which has antipyretic and antiinflammatory effects. Though it is known that the major side effect of non-steroidal antiinflammatory drugs is on the gastrointestinal tract and liver, there have been few studies regarding the effects of tenoxicam. In this study, we aimed to investigate whether tenoxicam has a deleterious effect on liver tissue using immunohistochemical staining and biochemical analysis. A total of 30 male Wistar albino rats were included in this study. Animals were equally and randomly divided into three groups as follows: Group I (Controls), Group II (Injection with 10 mg/kg/day of tenoxicam) and Group III (Injection with 20 mg/kg/day of tenoxicam). At the end of the study, some liver tissue samples were taken and kept in neutral formalin for histological and immunohistochemical evaluation. Liver tissue samples were embedded in paraffin blocks after routine tissue preparation procedures, and were stained with hematoxylin-eosin and immunohistochemical stain. Liver samples taken for biochemical analysis were washed with physiological saline. Thiobarbituric acid reactive substances and superoxide dismutase activity were measured in the obtained supernatants. There were significant structural changes in liver tissues of the tenoxicam-administered groups when compared with the controls. We observed that hepatic (inducible nitric oxide synthase) receptors were increased in the study groups. Furthermore, hepatic superoxide dismutase and malondialdehyde levels were prominently higher in the tenoxicam-administered groups when compared to levels of the control group. Nitric oxide may exert an antioxidative effect against lipid peroxidation to one point at low levels; however, it may also have the opposite effect at higher levels in tenoxicam induced liver injury.

  1. Quality assurance and auditing for tissue banking

    International Nuclear Information System (INIS)

    Strong, M.; Tayo, E.

    1999-01-01

    Implementation of quality systems can provide many benefits and have a direct impact on the cost of tissue banking. These benefits are achieved by reducing redundancies, streamlining work processes, reducing and waste, and implementing of a process of continuous monitoring and quality improvement, There have been various models written for the use of quality systems in tissue banking but most can be indexed and correlated with the universal ISO 9000 Quality Management System used world-wide in all types of businesses and services since 1986. These standards contain 20 system elements that define the broad-based quality system. Within these elements are included audited systems. The auditing system includes internal assessment and external assessment. An audit is a planned, independent and documented assessment to determine whether agreed upon requirements are being met. Audits are performed by qualified individuals with knowledge of procedures, regulations and associated standards with the primary intention of improving processes. Internal and external assessments are the primary types of audits performed at the tissue center. Internal assessment is performed by the employees of the organization to determine whether activities and -the results of the activities comply with requirements and procedures. External assessment is carried out by independent examinations performed by an external agency. This presentation will describe procedures for internal quality auditing and results of external assessment of tissue banking in North America, as performed by the American Association of Tissue Banks (AATB). The AATB system for external auditing will be described. Examples will be given of the most common errors found by such auditing assessments and procedures for establishing internal quality auditing

  2. Bone Tissue Engineering: Past-Present-Future.

    Science.gov (United States)

    Quarto, Rodolfo; Giannoni, Paolo

    2016-01-01

    Bone is one of the few tissues to display a true potential for regeneration. Fracture healing is an obvious example where regeneration occurs through tightly regulated sequences of molecular and cellular events which recapitulate tissue formation seen during embryogenesis. Still in some instances, bone regeneration does not occur properly (i.e. critical size lesions) and an appropriate therapeutic intervention is necessary. Successful replacement of bone by tissue engineering will likely depend on the recapitulation of this flow of events. In fact, bone regeneration requires cross-talk between microenvironmental factors and cells; for example, resident mesenchymal progenitors are recruited and properly guided by soluble and insoluble signaling molecules. Tissue engineering attempts to reproduce and to mimic this natural milieu by delivering cells capable of differentiating into osteoblasts, inducing growth factors and biomaterials to support cellular attachment, proliferation, migration, and matrix deposition. In the last two decades, a significant effort has been made by the scientific community in the development of methods and protocols to repair and regenerate tissues such as bone, cartilage, tendons, and ligaments. In this same period, great advancements have been achieved in the biology of stem cells and on the mechanisms governing "stemness". Unfortunately, after two decades, effective clinical translation does not exist, besides a few limited examples. Many years have passed since cell-based regenerative therapies were first described as "promising approaches", but this definition still engulfs the present literature. Failure to envisage translational cell therapy applications in routine medical practice evidences the existence of unresolved scientific and technical struggles, some of which still puzzle researchers in the field and are presented in this chapter.

  3. Cardiovascular Tissue Engineering: Preclinical Validation to Bedside Application

    Science.gov (United States)

    Best, Cameron; Onwuka, Ekene; Pepper, Victoria; Sams, Malik; Breuer, Jake

    2015-01-01

    Advancements in biomaterial science and available cell sources have spurred the translation of tissue-engineering technology to the bedside, addressing the pressing clinical demands for replacement cardiovascular tissues. Here, the in vivo status of tissue-engineered blood vessels, heart valves, and myocardium is briefly reviewed, illustrating progress toward a tissue-engineered heart for clinical use. PMID:26661524

  4. Effect of substrate choice and tissue type on tissue preparation for spectral histopathology by Raman microspectroscopy.

    Science.gov (United States)

    Fullwood, Leanne M; Griffiths, Dave; Ashton, Katherine; Dawson, Timothy; Lea, Robert W; Davis, Charles; Bonnier, Franck; Byrne, Hugh J; Baker, Matthew J

    2014-01-21

    Raman spectroscopy is a non-destructive, non-invasive, rapid and economical technique which has the potential to be an excellent method for the diagnosis of cancer and understanding disease progression through retrospective studies of archived tissue samples. Historically, biobanks are generally comprised of formalin fixed paraffin preserved tissue and as a result these specimens are often used in spectroscopic research. Tissue in this state has to be dewaxed prior to Raman analysis to reduce paraffin contributions in the spectra. However, although the procedures are derived from histopathological clinical practice, the efficacy of the dewaxing procedures that are currently employed is questionable. Ineffective removal of paraffin results in corruption of the spectra and previous experiments have shown that the efficacy can depend on the dewaxing medium and processing time. The aim of this study was to investigate the influence of commonly used spectroscopic substrates (CaF2, Spectrosil quartz and low-E slides) and the influence of different histological tissue types (normal, cancerous and metastatic) on tissue preparation and to assess their use for spectral histopathology. Results show that CaF2 followed by Spectrosil contribute the least to the spectral background. However, both substrates retain paraffin after dewaxing. Low-E substrates, which exhibit the most intense spectral background, do not retain wax and resulting spectra are not affected by paraffin peaks. We also show a disparity in paraffin retention depending upon the histological identity of the tissue with abnormal tissue retaining more paraffin than normal.

  5. Autofluorescence of healthy and inflamed pulpal tissues: photodynamic diagnosis of pulpal tissue

    Science.gov (United States)

    Ebihara, Arata; Kawashima, Nobuyuki; Saegusa, Hidetoshi; Anjo, Tomoo; Suda, Hideaki

    2005-03-01

    Autofluorescence of healthy and inflamed human pulpal tissues was observed by confocal laser microscopy. In this preliminary study, photodynamic diagnosis (PDD) was applied to diagnose pulpal disease. The ability to accurately diagnose pulpal pathology prior to pulpectomy would be very beneficial. Clinically, however, we are unable to perform biopsy to detect pathological changes. Therefore, this study was performed using healthy, acutely and chronically inflamed human pulpal tissues to detect pathological changes in pulpal tissues. Following excision, pulpal tissues were rapidly frozen and standard cryosections were prepared. Autofluorescence of pulpal tissues was observed using a confocal laser microscope to examine whether there were any differences in autofluorescence intensities between healthy and inflamed pulpal tissues. Several combinations of excitation and detection wavelengths were tested to observe autofluorescence from pulpal tissues; the excitation wavelengths ranged from 488nm to 633nm, and the detection wavelengths were longer than 505 nm. Autofluorescence was detected in both healthy and inflamed groups. With this technique, it may be possible to diagnose pulpal pathology without biopsy, and might be applicable to photodynamic diagnosis (PDD) and photodynamic therapy (PDT) in root canal treatment.

  6. Fabrication and characterization of scaffold from cadaver goat-lung tissue for skin tissue engineering applications.

    Science.gov (United States)

    Gupta, Sweta K; Dinda, Amit K; Potdar, Pravin D; Mishra, Narayan C

    2013-10-01

    The present study aims to fabricate scaffold from cadaver goat-lung tissue and evaluate it for skin tissue engineering applications. Decellularized goat-lung scaffold was fabricated by removing cells from cadaver goat-lung tissue enzymatically, to have cell-free 3D-architecture of natural extracellular matrix. DNA quantification assay and Hematoxylin and eosin staining confirmed the absence of cellular material in the decellularized lung-tissue. SEM analysis of decellularized scaffold shows the intrinsic porous structure of lung tissue with well-preserved pore-to-pore interconnectivity. FTIR analysis confirmed non-denaturation and well maintainance of collagenous protein structure of decellularized scaffold. MTT assay, SEM analysis and H&E staining of human skin-derived Mesenchymal Stem cell, seeded over the decellularized scaffold, confirms stem cell attachment, viability, biocompatibility and proliferation over the decellularized scaffold. Expression of Keratin18 gene, along with CD105, CD73 and CD44, by human skin-derived Mesenchymal Stem cells over decellularized scaffold signifies that the cells are viable, proliferating and migrating, and have maintained their critical cellular functions in the presence of scaffold. Thus, overall study proves the applicability of the goat-lung tissue derived decellularized scaffold for skin tissue engineering applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Decellularized Tissue and Cell-Derived Extracellular Matrices as Scaffolds for Orthopaedic Tissue Engineering

    Science.gov (United States)

    Cheng, Christina W.; Solorio, Loran D.; Alsberg, Eben

    2014-01-01

    The reconstruction of musculoskeletal defects is a constant challenge for orthopaedic surgeons. Musculoskeletal injuries such as fractures, chondral lesions, infections and tumor debulking can often lead to large tissue voids requiring reconstruction with tissue grafts. Autografts are currently the gold standard in orthopaedic tissue reconstruction; however, there is a limit to the amount of tissue that can be harvested before compromising the donor site. Tissue engineering strategies using allogeneic or xenogeneic decellularized bone, cartilage, skeletal muscle, tendon and ligament have emerged as promising potential alternative treatment. The extracellular matrix provides a natural scaffold for cell attachment, proliferation and differentiation. Decellularization of in vitro cell-derived matrices can also enable the generation of autologous constructs from tissue specific cells or progenitor cells. Although decellularized bone tissue is widely used clinically in orthopaedic applications, the exciting potential of decellularized cartilage, skeletal muscle, tendon and ligament cell-derived matrices has only recently begun to be explored for ultimate translation to the orthopaedic clinic. PMID:24417915

  8. Detection of neuronal tissue in meat using tissue specific DNA modifications

    Directory of Open Access Journals (Sweden)

    Harris N.

    2004-01-01

    Full Text Available A method has been developed to differentiate between non-muscle tissues such as liver, kidney and heart and that of muscle in meat samples using tissue specific DNA detection. Only muscle tissue is considered meat from the point of view of labelling (Food Labelling [Amendment] (England Regulations 2003 and Quantitative Ingredient Declaration (QUID, and also certain parts of the carcass are prohibited to be used in raw meat products (Meat Products [England] Regulations 2003. Included in the prohibited offal are brain and spinal cord. The described methodology has therefore been developed primarily to enforce labelling rules but also to contribute to the enforcement of BSE legislation on the detection of Central Nervous System (CNS tissue. The latter requires the removal of Specified Risk Material (SRM, such as bovine and ovine brain and spinal cord, from the food chain. Current methodologies for detection of CNS tissue include histological examination, analysis of cholesterol content and immunodetection. These can potentially be time consuming, less applicable to processed samples and may not be readily adapted to high throughput sample analysis. The objective of this work was therefore to develop a DNAbased detection assay that exploits the sensitivity and specificity of PCR and is potentially applicable to more highly processed food samples. For neuronal tissue, the DNA target selected was the promoter for Glial Fibrillary Acidic Protein (GFAP, a gene whose expression is restricted to astroglial cells within CNS tissue. The promoter fragments from both cattle and sheep have been isolated and key differences in the methylation patterns of certain CpG dinucleotides in the sequences from bovine and sheep brain and spinal cord and the corresponding skeletal muscle identified. These have been used to design a PCR assay exploiting Methylation Specific PCR (MSP to specifically amplify the neuronal tissue derived sequence and therefore identify the

  9. Growing tissues in real and simulated microgravity: new methods for tissue engineering.

    Science.gov (United States)

    Grimm, Daniela; Wehland, Markus; Pietsch, Jessica; Aleshcheva, Ganna; Wise, Petra; van Loon, Jack; Ulbrich, Claudia; Magnusson, Nils E; Infanger, Manfred; Bauer, Johann

    2014-12-01

    Tissue engineering in simulated (s-) and real microgravity (r-μg) is currently a topic in Space medicine contributing to biomedical sciences and their applications on Earth. The principal aim of this review is to highlight the advances and accomplishments in the field of tissue engineering that could be achieved by culturing cells in Space or by devices created to simulate microgravity on Earth. Understanding the biology of three-dimensional (3D) multicellular structures is very important for a more complete appreciation of in vivo tissue function and advancing in vitro tissue engineering efforts. Various cells exposed to r-μg in Space or to s-μg created by a random positioning machine, a 2D-clinostat, or a rotating wall vessel bioreactor grew in the form of 3D tissues. Hence, these methods represent a new strategy for tissue engineering of a variety of tissues, such as regenerated cartilage, artificial vessel constructs, and other organ tissues as well as multicellular cancer spheroids. These aggregates are used to study molecular mechanisms involved in angiogenesis, cancer development, and biology and for pharmacological testing of, for example, chemotherapeutic drugs or inhibitors of neoangiogenesis. Moreover, they are useful for studying multicellular responses in toxicology and radiation biology, or for performing coculture experiments. The future will show whether these tissue-engineered constructs can be used for medical transplantations. Unveiling the mechanisms of microgravity-dependent molecular and cellular changes is an up-to-date requirement for improving Space medicine and developing new treatment strategies that can be translated to in vivo models while reducing the use of laboratory animals.

  10. Fabrication and characterization of scaffold from cadaver goat-lung tissue for skin tissue engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Sweta K. [Department of Polymer and Process Engineering, Indian Institute of Technology, Roorkee (India); Dinda, Amit K. [Department of Pathology, All India Institute of Medical Sciences, New Delhi (India); Potdar, Pravin D. [Department of Molecular Medicine, Jaslok Hospital and Research Centre, Mumbai (India); Mishra, Narayan C., E-mail: mishrawise@gmail.com [Department of Polymer and Process Engineering, Indian Institute of Technology, Roorkee (India)

    2013-10-15

    The present study aims to fabricate scaffold from cadaver goat-lung tissue and evaluate it for skin tissue engineering applications. Decellularized goat-lung scaffold was fabricated by removing cells from cadaver goat-lung tissue enzymatically, to have cell-free 3D-architecture of natural extracellular matrix. DNA quantification assay and Hematoxylin and eosin staining confirmed the absence of cellular material in the decellularized lung-tissue. SEM analysis of decellularized scaffold shows the intrinsic porous structure of lung tissue with well-preserved pore-to-pore interconnectivity. FTIR analysis confirmed non-denaturation and well maintainance of collagenous protein structure of decellularized scaffold. MTT assay, SEM analysis and H and E staining of human skin-derived Mesenchymal Stem cell, seeded over the decellularized scaffold, confirms stem cell attachment, viability, biocompatibility and proliferation over the decellularized scaffold. Expression of Keratin18 gene, along with CD105, CD73 and CD44, by human skin-derived Mesenchymal Stem cells over decellularized scaffold signifies that the cells are viable, proliferating and migrating, and have maintained their critical cellular functions in the presence of scaffold. Thus, overall study proves the applicability of the goat-lung tissue derived decellularized scaffold for skin tissue engineering applications. - Highlights: • We successfully fabricated decellularized scaffold from cadaver goat-lung tissue. • Decellularized goat-lung scaffolds were found to be highly porous. • Skin derived MSC shows high cell viability and proliferation over the scaffold. • Phenotype of MSCs was well maintained over the scaffold. • The scaffold shows potential for applications in skin tissue engineering.

  11. Fabrication and characterization of scaffold from cadaver goat-lung tissue for skin tissue engineering applications

    International Nuclear Information System (INIS)

    Gupta, Sweta K.; Dinda, Amit K.; Potdar, Pravin D.; Mishra, Narayan C.

    2013-01-01

    The present study aims to fabricate scaffold from cadaver goat-lung tissue and evaluate it for skin tissue engineering applications. Decellularized goat-lung scaffold was fabricated by removing cells from cadaver goat-lung tissue enzymatically, to have cell-free 3D-architecture of natural extracellular matrix. DNA quantification assay and Hematoxylin and eosin staining confirmed the absence of cellular material in the decellularized lung-tissue. SEM analysis of decellularized scaffold shows the intrinsic porous structure of lung tissue with well-preserved pore-to-pore interconnectivity. FTIR analysis confirmed non-denaturation and well maintainance of collagenous protein structure of decellularized scaffold. MTT assay, SEM analysis and H and E staining of human skin-derived Mesenchymal Stem cell, seeded over the decellularized scaffold, confirms stem cell attachment, viability, biocompatibility and proliferation over the decellularized scaffold. Expression of Keratin18 gene, along with CD105, CD73 and CD44, by human skin-derived Mesenchymal Stem cells over decellularized scaffold signifies that the cells are viable, proliferating and migrating, and have maintained their critical cellular functions in the presence of scaffold. Thus, overall study proves the applicability of the goat-lung tissue derived decellularized scaffold for skin tissue engineering applications. - Highlights: • We successfully fabricated decellularized scaffold from cadaver goat-lung tissue. • Decellularized goat-lung scaffolds were found to be highly porous. • Skin derived MSC shows high cell viability and proliferation over the scaffold. • Phenotype of MSCs was well maintained over the scaffold. • The scaffold shows potential for applications in skin tissue engineering

  12. Negating Tissue Contracture Improves Volume Maintenance and Longevity of In Vivo Engineered Tissues.

    Science.gov (United States)

    Lytle, Ian F; Kozlow, Jeffrey H; Zhang, Wen X; Buffington, Deborah A; Humes, H David; Brown, David L

    2015-10-01

    Engineering large, complex tissues in vivo requires robust vascularization to optimize survival, growth, and function. Previously, the authors used a "chamber" model that promotes intense angiogenesis in vivo as a platform for functional three-dimensional muscle and renal engineering. A silicone membrane used to define the structure and to contain the constructs is successful in the short term. However, over time, generated tissues contract and decrease in size in a manner similar to capsular contracture seen around many commonly used surgical implants. The authors hypothesized that modification of the chamber structure or internal surface would promote tissue adherence and maintain construct volume. Three chamber configurations were tested against volume maintenance. Previously studied, smooth silicone surfaces were compared to chambers modified for improved tissue adherence, with multiple transmembrane perforations or lined with a commercially available textured surface. Tissues were allowed to mature long term in a rat model, before analysis. On explantation, average tissue masses were 49, 102, and 122 mg; average volumes were 74, 158 and 176 μl; and average cross-sectional areas were 1.6, 6.7, and 8.7 mm for the smooth, perforated, and textured groups, respectively. Both perforated and textured designs demonstrated significantly greater measures than the smooth-surfaced constructs in all respects. By modifying the design of chambers supporting vascularized, three-dimensional, in vivo tissue engineering constructs, generated tissue mass, volume, and area can be maintained over a long time course. Successful progress in the scale-up of construct size should follow, leading to improved potential for development of increasingly complex engineered tissues.

  13. [Differentiation of mesenchymal stem cells of adipose tissue].

    Science.gov (United States)

    Salyutin, R V; Zapohlska, K M; Palyanytsya, S S; Sirman, V M; Sokolov, M F

    2015-03-01

    Experimental investigation were conducted with the objective to determine a stem cells, capacity to differentiate in adipogenic direction, if they were obtained from adipose tissue. The investigation results have witnessed, that the cells, obtained from adipose tissue, are capable for a tissue-speciphic differentiation in osteogenic, chondrogenic, and, principally--in adipogenic direction, what confirms a multypotent nature of mesenchymal stem cells of adipose tissue. Adipose tissue constitutes an alternative to the bone marrow, as a source of multipotent mesenchymal stem cells, which may be applied in further investigations, concerning determination of their defense possibility for the transplanted autologous adipose tissue from the tissue resorption, made in a lipophiling way.

  14. 3D Printing and Biofabrication for Load Bearing Tissue Engineering.

    Science.gov (United States)

    Jeong, Claire G; Atala, Anthony

    2015-01-01

    Cell-based direct biofabrication and 3D bioprinting is becoming a dominant technological platform and is suggested as a new paradigm for twenty-first century tissue engineering. These techniques may be our next step in surpassing the hurdles and limitations of conventional scaffold-based tissue engineering, and may offer the industrial potential of tissue engineered products especially for load bearing tissues. Here we present a topically focused review regarding the fundamental concepts, state of the art, and perspectives of this new technology and field of biofabrication and 3D bioprinting, specifically focused on tissue engineering of load bearing tissues such as bone, cartilage, osteochondral and dental tissue engineering.

  15. Collagenous Extracellular Matrix Biomaterials for Tissue Engineering: Lessons from the Common Sea Urchin Tissue

    Directory of Open Access Journals (Sweden)

    Kheng Lim Goh

    2017-04-01

    Full Text Available Scaffolds for tissue engineering application may be made from a collagenous extracellular matrix (ECM of connective tissues because the ECM can mimic the functions of the target tissue. The primary sources of collagenous ECM material are calf skin and bone. However, these sources are associated with the risk of having bovine spongiform encephalopathy or transmissible spongiform encephalopathy. Alternative sources for collagenous ECM materials may be derived from livestock, e.g., pigs, and from marine animals, e.g., sea urchins. Collagenous ECM of the sea urchin possesses structural features and mechanical properties that are similar to those of mammalian ones. However, even more intriguing is that some tissues such as the ligamentous catch apparatus can exhibit mutability, namely rapid reversible changes in the tissue mechanical properties. These tissues are known as mutable collagenous tissues (MCTs. The mutability of these tissues has been the subject of on-going investigations, covering the biochemistry, structural biology and mechanical properties of the collagenous components. Recent studies point to a nerve-control system for regulating the ECM macromolecules that are involved in the sliding action of collagen fibrils in the MCT. This review discusses the key attributes of the structure and function of the ECM of the sea urchin ligaments that are related to the fibril-fibril sliding action—the focus is on the respective components within the hierarchical architecture of the tissue. In this context, structure refers to size, shape and separation distance of the ECM components while function is associated with mechanical properties e.g., strength and stiffness. For simplicity, the components that address the different length scale from the largest to the smallest are as follows: collagen fibres, collagen fibrils, interfibrillar matrix and collagen molecules. Application of recent theories of stress transfer and fracture mechanisms in fibre

  16. Collagenous Extracellular Matrix Biomaterials for Tissue Engineering: Lessons from the Common Sea Urchin Tissue.

    Science.gov (United States)

    Goh, Kheng Lim; Holmes, David F

    2017-04-25

    Scaffolds for tissue engineering application may be made from a collagenous extracellular matrix (ECM) of connective tissues because the ECM can mimic the functions of the target tissue. The primary sources of collagenous ECM material are calf skin and bone. However, these sources are associated with the risk of having bovine spongiform encephalopathy or transmissible spongiform encephalopathy. Alternative sources for collagenous ECM materials may be derived from livestock, e.g., pigs, and from marine animals, e.g., sea urchins. Collagenous ECM of the sea urchin possesses structural features and mechanical properties that are similar to those of mammalian ones. However, even more intriguing is that some tissues such as the ligamentous catch apparatus can exhibit mutability, namely rapid reversible changes in the tissue mechanical properties. These tissues are known as mutable collagenous tissues (MCTs). The mutability of these tissues has been the subject of on-going investigations, covering the biochemistry, structural biology and mechanical properties of the collagenous components. Recent studies point to a nerve-control system for regulating the ECM macromolecules that are involved in the sliding action of collagen fibrils in the MCT. This review discusses the key attributes of the structure and function of the ECM of the sea urchin ligaments that are related to the fibril-fibril sliding action-the focus is on the respective components within the hierarchical architecture of the tissue. In this context, structure refers to size, shape and separation distance of the ECM components while function is associated with mechanical properties e.g., strength and stiffness. For simplicity, the components that address the different length scale from the largest to the smallest are as follows: collagen fibres, collagen fibrils, interfibrillar matrix and collagen molecules. Application of recent theories of stress transfer and fracture mechanisms in fibre reinforced

  17. Monitoring of tissue optical properties during thermal coagulation of ex vivo tissues.

    Science.gov (United States)

    Nagarajan, Vivek Krishna; Yu, Bing

    2016-09-01

    Real-time monitoring of tissue status during thermal ablation of tumors is critical to ensure complete destruction of tumor mass, while avoiding tissue charring and excessive damage to normal tissues. Currently, magnetic resonance thermometry (MRT), along with magnetic resonance imaging (MRI), is the most commonly used technique for monitoring and assessing thermal ablation process in soft tissues. MRT/MRI is very expensive, bulky, and often subject to motion artifacts. On the other hand, light propagation within tissue is sensitive to changes in tissue microstructure and physiology which could be used to directly quantify the extent of tissue damage. Furthermore, optical monitoring can be a portable, and cost-effective alternative for monitoring a thermal ablation process. The main objective of this study, is to establish a correlation between changes in tissue optical properties and the status of tissue coagulation/damage during heating of ex vivo tissues. A portable diffuse reflectance spectroscopy system and a side-firing fiber-optic probe were developed to study the absorption (μa (λ)), and reduced scattering coefficients (μ's (λ)) of native and coagulated ex vivo porcine, and chicken breast tissues. In the first experiment, both porcine and chicken breast tissues were heated at discrete temperature points between 24 and 140°C for 2 minutes. Diffuse reflectance spectra (430-630 nm) of native and coagulated tissues were recorded prior to, and post heating. In a second experiment, porcine tissue samples were heated at 70°C and diffuse reflectance spectra were recorded continuously during heating. The μa (λ) and μ's (λ) of the tissues were extracted from the measured diffuse reflectance spectra using an inverse Monte-Carlo model of diffuse reflectance. Tissue heating was stopped when the wavelength-averaged scattering plateaued. The wavelength-averaged optical properties, and , for native porcine tissues (n = 66) at room temperature, were 5.4

  18. Signalement af den gode og effektive lærer- eleverne har ordet

    DEFF Research Database (Denmark)

    Bjerresgaard, Helle

    The title of this master’s thesis – ”Description of the skilled and efficient educator – the pupils have the floor”, is closely connected to a recently published book by Per Fibæk Laursen called, ”The Authentic Teacher. Become a skilled and efficient educator – if you want to”, a book which has...... contributed to the present educational debate. The book is based on qualitative interviews with 30 teachers about their jobs and their personal development. This is no coincidence. The current pedagogical debate does not only focus on professional and practical pedagogical skills. It also focuses...... on the significance of the educator’s personality. The book implicates the teacher’s personality and personal skills and uses these to explain why teaching sometimes are successful and sometimes not. Is it possible to expose those shared and fundamental qualities of teaching which result in successful teaching – “the...

  19. Effekt evaluering af Svangre-Føde Journal i Region Nordjylland

    DEFF Research Database (Denmark)

    Barlach, Anders

    specifikationer og prototyper der også tager stilling til en organiseringen af målinger med henblik på evaluering. Den teoretiske gennemgang efterfølges af den konkrete fremstilling af måle- og evalueringsdesign af Svangre-føde journalen i Region Nordjylland. Resultaterne er genstand for en statistisk...

  20. Multifunctional facades - design optimisation with CAD; Multifunktionale Fassaden - Effektive Auslegung durch CAD-Einsatz

    Energy Technology Data Exchange (ETDEWEB)

    Viotto, M. [Institut fuer Solare Energieversorgungstechnik (ISET), Kassel (Germany). Abt. fuer Anlagen- und Messtechnik

    1998-02-01

    The energetically optimal design of PV facades requires the consideration of many technical conditions (different elevations/orientations of modules; shading possibility; high and different module temperatures). It also requires the interface with architecture, civil and electrical engineering. To support this planning process, the software program PV-CAD was developed which rapidly calculates energy yield under conditions of inhomogeneous irradiance, shading, thermal behaviour of modules and electrical layout. PV-CAD is compatible with other civil and electrical engineering CAD programs and incorporates extensive databases (weather data; modules and inverter types). (orig.) [Deutsch] Fuer optimalen Energieertrag sind zahlreiche technische Randbedingungen bei der Auslegung einer Photovoltaik (PV)-Fassade zu beruecksichtigen (unterschiedliche Ausrichtungen/Neigungen der Module; moegliche Teilabschattung; hoehere und unterschiedliche Betriebstemperaturen). Installation und Betrieb einer PV-Fassade erfordern die Abstimmung zwischen Architektur, Bauwesen und Elektrotechnik. Zur Unterstuetzung der Planer wurde das Programm PV-CAD entwickelt, das den Energieertrag unter Beruecksichtigung von inhomogener Einstrahlung und Abschattung, Temperaturverhalten der Fassadenmodule sowie unterschiedlichen elektrischen Anlagenkonzepten schnell ermittelt; es fuegt sich nahtlos in CAD-Arbeitsumgebungen ein. (orig.)