ATE290351T1 - BIOAKTIVER ABBAUBARER VERBUNDSTOFF FÜR ßTISSUE ENGINEERINGß - Google Patents

BIOAKTIVER ABBAUBARER VERBUNDSTOFF FÜR ßTISSUE ENGINEERINGß

Info

Publication number
ATE290351T1
ATE290351T1 AT00991390T AT00991390T ATE290351T1 AT E290351 T1 ATE290351 T1 AT E290351T1 AT 00991390 T AT00991390 T AT 00991390T AT 00991390 T AT00991390 T AT 00991390T AT E290351 T1 ATE290351 T1 AT E290351T1
Authority
AT
Austria
Prior art keywords
ßtissue
engineeringß
degradable composite
bioactive
bioactive degradable
Prior art date
Application number
AT00991390T
Other languages
German (de)
English (en)
Inventor
Paul Ducheyne
Portonovo S Ayyaswamy
Qing-Qing Qui
Original Assignee
Univ Pennsylvania
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Univ Pennsylvania filed Critical Univ Pennsylvania
Application granted granted Critical
Publication of ATE290351T1 publication Critical patent/ATE290351T1/de

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C4/00—Compositions for glass with special properties
    • C03C4/0007—Compositions for glass with special properties for biologically-compatible glass
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
    • A61L27/28—Materials for coating prostheses
    • A61L27/30—Inorganic materials
    • A61L27/32—Phosphorus-containing materials, e.g. apatite
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
    • A61L27/40—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material
    • A61L27/44—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material having a macromolecular matrix
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
    • A61L27/40—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material
    • A61L27/44—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material having a macromolecular matrix
    • A61L27/446—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material having a macromolecular matrix with other specific inorganic fillers other than those covered by A61L27/443 or A61L27/46
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C12/00—Powdered glass; Bead compositions
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/28—Bones
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2002/30001—Additional features of subject-matter classified in A61F2/28, A61F2/30 and subgroups thereof
    • A61F2002/30003—Material related properties of the prosthesis or of a coating on the prosthesis
    • A61F2002/3006—Properties of materials and coating materials
    • A61F2002/30062—(bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2002/30001—Additional features of subject-matter classified in A61F2/28, A61F2/30 and subgroups thereof
    • A61F2002/30667—Features concerning an interaction with the environment or a particular use of the prosthesis
    • A61F2002/30677—Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2210/00—Particular material properties of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
    • A61F2210/0004—Particular material properties of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof bioabsorbable
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2310/00—Prostheses classified in A61F2/28 or A61F2/30 - A61F2/44 being constructed from or coated with a particular material
    • A61F2310/00005—The prosthesis being constructed from a particular material
    • A61F2310/00179—Ceramics or ceramic-like structures
    • A61F2310/00293—Ceramics or ceramic-like structures containing a phosphorus-containing compound, e.g. apatite

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Materials Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Epidemiology (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • General Health & Medical Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • Transplantation (AREA)
  • Dermatology (AREA)
  • Medicinal Chemistry (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Composite Materials (AREA)
  • Inorganic Chemistry (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Organic Chemistry (AREA)
  • Molecular Biology (AREA)
  • Materials For Medical Uses (AREA)
  • Medicinal Preparation (AREA)
AT00991390T 1999-11-12 2000-11-10 BIOAKTIVER ABBAUBARER VERBUNDSTOFF FÜR ßTISSUE ENGINEERINGß ATE290351T1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US09/439,183 US6328990B1 (en) 1999-11-12 1999-11-12 Bioactive, degradable composite for tissue engineering
PCT/US2000/030947 WO2001034060A1 (en) 1999-11-12 2000-11-10 Bioactive, degradable composite for tissue engineering

Publications (1)

Publication Number Publication Date
ATE290351T1 true ATE290351T1 (de) 2005-03-15

Family

ID=23743660

Family Applications (1)

Application Number Title Priority Date Filing Date
AT00991390T ATE290351T1 (de) 1999-11-12 2000-11-10 BIOAKTIVER ABBAUBARER VERBUNDSTOFF FÜR ßTISSUE ENGINEERINGß

Country Status (8)

Country Link
US (1) US6328990B1 (enExample)
EP (1) EP1233721B1 (enExample)
JP (1) JP2003513701A (enExample)
AT (1) ATE290351T1 (enExample)
AU (1) AU774288B2 (enExample)
CA (1) CA2391232A1 (enExample)
DE (1) DE60018600T2 (enExample)
WO (1) WO2001034060A1 (enExample)

Families Citing this family (48)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020155559A1 (en) * 2001-01-17 2002-10-24 Laurencin Cato T. Biocompatible, biodegradable polymer-based, lighter than or light as water scaffolds for tissue engineering and methods for preparation and use thereof
AU2002258637A1 (en) 2001-03-27 2002-10-08 Board Of Regents The University Of Texas System Biodegradable, electrically conductiong polymer for tissue engineering applications
CN1294885C (zh) * 2001-06-05 2007-01-17 江苏阳生生物工程有限公司 人体骨组织生物工程支架制品及其制备方法和用途
WO2003000156A1 (en) 2001-06-22 2003-01-03 Southern Biosystems, Inc. Zero-order prolonged release coaxial implants
US20030220692A1 (en) * 2002-02-09 2003-11-27 Shapiro Irving M. Preparations of nucleus pulposus cells and methods for their generation, identification, and use
AU2003304348A1 (en) * 2002-03-15 2005-02-04 The Trustees Of The University Of Pennsylvania Fibrous composite for tissue engineering
AU2003251899A1 (en) * 2002-07-10 2004-01-23 University Of Florida Sol-gel derived bioactive glass polymer composite
US7066962B2 (en) * 2002-07-23 2006-06-27 Porex Surgical, Inc. Composite surgical implant made from macroporous synthetic resin and bioglass particles
WO2004039248A2 (en) * 2002-10-31 2004-05-13 The General Hospital Corporation Repairing or replacing tissues or organs
US20060140904A1 (en) * 2003-02-12 2006-06-29 Tadeusz Wellisz Random alkylene oxide copolymers for medical and surgical utilities
JP2007509716A (ja) * 2003-10-29 2007-04-19 ジェンティス インコーポレイテッド 組織工学用の重合可能なエマルション
US8012210B2 (en) 2004-01-16 2011-09-06 Warsaw Orthopedic, Inc. Implant frames for use with settable materials and related methods of use
EP1729675A4 (en) * 2004-03-05 2011-05-18 Univ Columbia MULTI-PHASE BIODEGRADABLE AND EAST-INTEGRATIVE COMPOSITE SCULPTURE FOR THE BIOLOGICAL FIXATION OF SKELETAL MOLECULAR WEAVE ON BONE
US7189409B2 (en) * 2004-03-09 2007-03-13 Inion Ltd. Bone grafting material, method and implant
JP2006101986A (ja) * 2004-10-01 2006-04-20 Olympus Corp 球状セラミックス粒子の製造方法、細胞の播種方法および生体組織補填体の製造方法
WO2006137787A1 (en) * 2005-06-21 2006-12-28 Ge Healthcare Bio-Sciences Ab Method for cell culture
US20070148251A1 (en) 2005-12-22 2007-06-28 Hossainy Syed F A Nanoparticle releasing medical devices
AU2007207495A1 (en) 2006-01-19 2007-07-26 Warsaw Orthopedic, Inc. Porous osteoimplant
WO2007084725A2 (en) 2006-01-19 2007-07-26 Osteotech, Inc. Injectable and moldable bone substitute materials
US20070249044A1 (en) * 2006-01-30 2007-10-25 University Of Illinois At Chicago Microstructures in three dimensional gel suspensions for growth of cells
AU2007232187A1 (en) * 2006-03-31 2007-10-11 Csir Bulking of soft tissue
US20080081362A1 (en) * 2006-09-29 2008-04-03 Daniel Keeley Multilayered Composite for Organ Augmentation and Repair
US20080119927A1 (en) * 2006-11-17 2008-05-22 Medtronic Vascular, Inc. Stent Coating Including Therapeutic Biodegradable Glass, and Method of Making
CN101200532B (zh) * 2006-12-12 2011-04-27 上海杰事杰新材料股份有限公司 高分子量聚己内酯等可生物降解材料中空球的制备方法
US8753391B2 (en) 2007-02-12 2014-06-17 The Trustees Of Columbia University In The City Of New York Fully synthetic implantable multi-phased scaffold
US20100143439A1 (en) * 2007-04-16 2010-06-10 University Of Toledo Hybrid Biomimetic Particles, Methods of Making Same and Uses Therefor
US20100317112A1 (en) * 2007-04-27 2010-12-16 Hyunjin Yang Scaffolds increased specific gravity for cell culture and method for manufacturing thereof
WO2008142129A2 (en) * 2007-05-22 2008-11-27 Cinvention Ag Partially degradable scaffolds for biomedical applications
DE102007031945A1 (de) * 2007-07-06 2009-01-08 Resoimplant Gmbh Bioresorbierbares Implantat
US8227246B2 (en) 2007-07-12 2012-07-24 Discgenics Compositions of adult disc stem cells for the treatment of degenerative disc disease
US8591933B2 (en) * 2007-07-18 2013-11-26 The Board Of Trustees Of The University Of Illinois Temporal release of growth factors from 3D micro rod scaffolds for tissue regeneration
US9144629B2 (en) 2010-03-03 2015-09-29 Novabone Products, Llc Ionically crosslinked materials and methods for production
WO2015147923A1 (en) 2010-03-03 2015-10-01 Novabone Products, Llc Kit for delivering bone grafting materials
WO2011109581A1 (en) 2010-03-03 2011-09-09 Novabone Products, Llc Devices and methods for the regeneration of bony defects
US10646514B2 (en) 2013-03-14 2020-05-12 Novabone Products, Llc Processing methods of solgel-derived bioactive glass-ceramic compositions and methods of using the same
EP2983643A4 (en) 2013-04-12 2016-12-28 Univ Columbia PROCESS FOR HOST CELL HOMING AND TOOTH MARK GENERATION
US20170342383A1 (en) 2016-05-27 2017-11-30 Corning Incorporated Lithium disilicate glass-ceramic compositions and methods thereof
US10676713B2 (en) 2016-05-27 2020-06-09 Corning Incorporated Bioactive borophosphate glasses
US10751367B2 (en) 2016-05-27 2020-08-25 Corning Incorporated Bioactive glass microspheres
US10647962B2 (en) 2016-05-27 2020-05-12 Corning Incorporated Bioactive aluminoborate glasses
KR20190073349A (ko) * 2016-10-05 2019-06-26 본어라이브 바이오메터리얼스 오와이 골 이식재
EP3717427A1 (en) 2017-11-28 2020-10-07 Corning Incorporated High liquidus viscosity bioactive glass
EP3717428A1 (en) 2017-11-28 2020-10-07 Corning Incorporated Bioactive borate glass and methods thereof
EP3717030A1 (en) 2017-11-28 2020-10-07 Corning Incorporated Bioactive glass compositions and dentin hypersensitivity remediation
CN111417601A (zh) 2017-11-28 2020-07-14 康宁股份有限公司 化学强化的生物活性玻璃陶瓷
CN108283729B (zh) * 2018-01-31 2020-06-26 北京化工大学 具有可控镁离子释放行为的可注射骨修复材料及其制备方法
CN109265942B (zh) * 2018-08-16 2021-10-19 张海军 一种聚乳酸微球及其制备方法与应用
CN109331223B (zh) * 2018-09-25 2021-07-30 广州润虹医药科技股份有限公司 一种载药生物活性玻璃复合磷酸钙骨水泥及其应用

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2651320B2 (ja) * 1992-07-16 1997-09-10 田辺製薬株式会社 徐放性マイクロスフェア製剤の製造方法
US5626861A (en) * 1994-04-01 1997-05-06 Massachusetts Institute Of Technology Polymeric-hydroxyapatite bone composite
EP0795336B1 (en) * 1995-09-14 2003-06-11 Takiron Co. Ltd. Osteosynthetic material, composited implant material, and process for preparing the same
US6224913B1 (en) * 1996-05-09 2001-05-01 The Trustees Of The University Of Pennsylvania Conditioning of bioactive glass surfaces in protein containing solutions
US5964807A (en) * 1996-08-08 1999-10-12 Trustees Of The University Of Pennsylvania Compositions and methods for intervertebral disc reformation
JP3451417B2 (ja) * 1996-08-12 2003-09-29 タキロン株式会社 バイオセラミックス含有セル構造体とその製造方法
US5977204A (en) * 1997-04-11 1999-11-02 Osteobiologics, Inc. Biodegradable implant material comprising bioactive ceramic
US5972384A (en) * 1997-10-01 1999-10-26 University Of Maryland, Baltimore Use of biologically active glass as a drug delivery system

Also Published As

Publication number Publication date
JP2003513701A (ja) 2003-04-15
DE60018600T2 (de) 2005-07-28
US6328990B1 (en) 2001-12-11
DE60018600D1 (de) 2005-04-14
WO2001034060A1 (en) 2001-05-17
EP1233721A1 (en) 2002-08-28
CA2391232A1 (en) 2001-05-17
AU3262301A (en) 2001-06-06
AU774288B2 (en) 2004-06-24
EP1233721B1 (en) 2005-03-09
EP1233721A4 (en) 2003-07-23

Similar Documents

Publication Publication Date Title
ATE290351T1 (de) BIOAKTIVER ABBAUBARER VERBUNDSTOFF FÜR ßTISSUE ENGINEERINGß
ATE361977T1 (de) In vitro verfahren zur induzierung der regulierten pankreatische-hormon produktion in nicht-pankreatischen inselngeweben, damit verbundene pharmazeutische zusammenseztzungen
MXPA03005553A (es) Protesis vascular mejorada y metodo para produccion de la misma.
ES2118251T3 (es) Preparaciones de microparticulas a base de copolimeros biologicamente degradables.
FI970218L (fi) Koostumuksia ja menetelmiä biologisesti keinotekoista, solun ulkopuolista matriisia varten
ATE268353T1 (de) Verfahren zur herstellung von mit antioxidant gedoptem uhmwpe und daraus hergestelltes implantat
NO20002785L (no) Adamantanderivater
NO20002786L (no) Adamantanderivater
AU1287895A (en) Differentially biodegradable biomedical implants
ATE357193T1 (de) Bioaktive lasttragende zusammensetzungen zum knochenverbund
BR0107942A (pt) Polìmeros de proteìna de liberação lenta
ATE409023T1 (de) Wirkstoffverabreichungssysteme mit verzögerter freisetzung, verwendung und verfahren zur herstellung derselben
WO2003007787A3 (en) Cartilage repair and regeneration device and method
ATE209918T1 (de) Transdermales estradiol/progestogen-pflaster und dessen herstellung
EP1072273A4 (en) VASKULARISIERUNGSINHIBITOREN
GB9410533D0 (en) In situ hybridisation and immuno-Chemical localisation of a growth factor
SE9704546D0 (sv) Novel compounds
TNSN05046A1 (en) Method of preparing dry powder inhalation compositions
ATE285754T1 (de) Pharmazeutische zusammensetzung mit lyophilisierten lyposomen welche einen unlöslichen aktiven wirkstoff einschliessen, verfahren zu dessen herstellung
BR0005413B1 (pt) processo para preparar uma plataforma polimÉrica porosa, biodegradÁvel e biocompatÍvel para engenharia de tecidos.
PT975334E (pt) Microparticulas biodegradaveis para a libertacao sustentada de farmacos terapeuticos
MY129001A (en) Treatment of emphysema using rar selective retinoid antagonists
DE50101479D1 (de) Fluoresceinisothiocyanat-(fitc)-sinistrin, seine herstellung und verwendung
IL135316A0 (en) Oxyranyle-triazoline thiones and their use as microbicides
ATA156590A (de) Mono-(2-ammonium-2-hydroxymethyl-1,3-propandiol (2r,cis)-1,2-epoxypropylphosphonat und verfahren zu dessen herstellung sowie pharmazeutische zusammensetzungen

Legal Events

Date Code Title Description
RER Ceased as to paragraph 5 lit. 3 law introducing patent treaties