Long-term renal transplant function in recipient of simultaneous kidney and pancreas transplant maintained with two prednisone-free maintenance immunosuppressive combinations: Tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus

It is not known how different steroid-free immunosuppressive combinations affect long-term kidney transplant function in recipients of simultaneous kidney and pancreas transplant (SPK). Here, we sought to evaluate, in SPK recipients, the impact on long-term renal allograft function of two Tac-based...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Transplantation 2007-05, Vol.83 (10), p.1324-1329
Hauptverfasser: GALLON, Lorenzo G, WINOTO, Johan, CHHABRA, Darshika, PARKER, Michele A, LEVENTHAL, Joseph R, KAUFMAN, Dixon B
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
container_end_page 1329
container_issue 10
container_start_page 1324
container_title Transplantation
container_volume 83
creator GALLON, Lorenzo G
WINOTO, Johan
CHHABRA, Darshika
PARKER, Michele A
LEVENTHAL, Joseph R
KAUFMAN, Dixon B
description It is not known how different steroid-free immunosuppressive combinations affect long-term kidney transplant function in recipients of simultaneous kidney and pancreas transplant (SPK). Here, we sought to evaluate, in SPK recipients, the impact on long-term renal allograft function of two Tac-based prednisone-free maintenance immunosuppressive protocols: tacrolimus (Tac)/mycophonelate mofetil (MMF) versus Tac/ sirolimus (SRL). In this single-center, retrospective, sequential study, we analyzed 59 SPK transplant patients with at median follow up of 5 years. All patients received induction therapy with thymoglobulin and maintenance immunosuppression with Tac/MMF (n=22) or Tac/SRL (n=37). There were no differences between the two groups in regards to age, gender, race, panel reactive antibodies, degree of mismatch, donor age, incidence of delay graft function, and Tac trough levels at different time points after transplantation. Kaplan-Meier patient survival at 6 years after transplantation was not statistically different between the two groups. Rate of ACR was similar. Kidney survival, even if not statistically significant, was better in the Tac/MMF group than in the Tac/SRL (90.7% vs. 70.7%, P=0.09). The slope of glomerular filtration rate decline per month at 5 years after transplantation was not statistically different between the two groups. Both groups had the same decline over time in glomerular filtration rate of 0.40+/-0.06 mL/min/1.73/month. Pancreas survival at 6 years after transplantation was 100% in both treatment groups. Our data suggest that, in SPK recipients, long-term kidney allograft survival and function are not statistically different. A trend toward an increased rate of renal allograft loss was found in the Tac/SRL-treated group.
doi_str_mv 10.1097/01.tp.0000264189.58324.91
format Article
fullrecord <record><control><sourceid>proquest_cross</sourceid><recordid>TN_cdi_proquest_miscellaneous_70524801</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>70524801</sourcerecordid><originalsourceid>FETCH-LOGICAL-c458t-7e16be6f536b24999a4fd32c2a1be8561840756d8df3334ab45658ece62e635a3</originalsourceid><addsrcrecordid>eNqFks-O1SAYxRujce6MvoLBhe7agfLfnZnoaHITN-O6ofSrg7ZQgc7kvrMPIdfb5LobEgKBH-c7wKmqtwQ3BGt5jUmTlwaX1gpGlG64oi1rNHlW7QinrBZY4efVDmNGakKpvKguU_pZeE6lfFldEMmJlorsqj_74H_UGeKMIngzoRyNT8tkfEbj6m12wSPny6Z1i4OyGkaU3LxO2XgIa0K_3ODhgIwf0GK8jWDS_yKzcT6XDgN6dPke5ceAlgiDdyl4qMcIcGJKdW8BuXlefUjrUqCU3AMgG-beeXN0kj6gO2NjmIqBdD0fbFjuwYfJ5CISRshuQg8QU7GVz1xy2-xV9WI0U4LX23hVff_86e7mS73_dvv15uO-toyrXEsgogcxcir6lmmtDRsH2trWkB4UF0QxLLkY1DBSSpnpGRdcgQXRgqDc0Kvq_Ul3ieH3Cil3s0sWpun0ZJ3EvGUKkyfBFgshJdNPgkQLTSVrC6hPYLl9ShHGboluNvHQEdwdw9Nh0uWlO4en-xeeTh_dvNmKrP0Mw_nklpYCvNsAk6yZxvLL1qUzp6RWuFX0L3KE12s</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>19693742</pqid></control><display><type>article</type><title>Long-term renal transplant function in recipient of simultaneous kidney and pancreas transplant maintained with two prednisone-free maintenance immunosuppressive combinations: Tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus</title><source>MEDLINE</source><source>Journals@Ovid Complete</source><creator>GALLON, Lorenzo G ; WINOTO, Johan ; CHHABRA, Darshika ; PARKER, Michele A ; LEVENTHAL, Joseph R ; KAUFMAN, Dixon B</creator><creatorcontrib>GALLON, Lorenzo G ; WINOTO, Johan ; CHHABRA, Darshika ; PARKER, Michele A ; LEVENTHAL, Joseph R ; KAUFMAN, Dixon B</creatorcontrib><description>It is not known how different steroid-free immunosuppressive combinations affect long-term kidney transplant function in recipients of simultaneous kidney and pancreas transplant (SPK). Here, we sought to evaluate, in SPK recipients, the impact on long-term renal allograft function of two Tac-based prednisone-free maintenance immunosuppressive protocols: tacrolimus (Tac)/mycophonelate mofetil (MMF) versus Tac/ sirolimus (SRL). In this single-center, retrospective, sequential study, we analyzed 59 SPK transplant patients with at median follow up of 5 years. All patients received induction therapy with thymoglobulin and maintenance immunosuppression with Tac/MMF (n=22) or Tac/SRL (n=37). There were no differences between the two groups in regards to age, gender, race, panel reactive antibodies, degree of mismatch, donor age, incidence of delay graft function, and Tac trough levels at different time points after transplantation. Kaplan-Meier patient survival at 6 years after transplantation was not statistically different between the two groups. Rate of ACR was similar. Kidney survival, even if not statistically significant, was better in the Tac/MMF group than in the Tac/SRL (90.7% vs. 70.7%, P=0.09). The slope of glomerular filtration rate decline per month at 5 years after transplantation was not statistically different between the two groups. Both groups had the same decline over time in glomerular filtration rate of 0.40+/-0.06 mL/min/1.73/month. Pancreas survival at 6 years after transplantation was 100% in both treatment groups. Our data suggest that, in SPK recipients, long-term kidney allograft survival and function are not statistically different. A trend toward an increased rate of renal allograft loss was found in the Tac/SRL-treated group.</description><identifier>ISSN: 0041-1337</identifier><identifier>EISSN: 1534-6080</identifier><identifier>DOI: 10.1097/01.tp.0000264189.58324.91</identifier><identifier>PMID: 17519781</identifier><identifier>CODEN: TRPLAU</identifier><language>eng</language><publisher>Hagerstown, MD: Lippincott</publisher><subject>Adult ; Antibiotics. Antiinfectious agents. Antiparasitic agents ; Antiviral agents ; Biological and medical sciences ; Cohort Studies ; Drug Therapy, Combination ; Female ; Follow-Up Studies ; Fundamental and applied biological sciences. Psychology ; Fundamental immunology ; Graft Rejection - epidemiology ; Graft Survival ; Humans ; Immunosuppressive Agents - therapeutic use ; Kidney Transplantation - immunology ; Kidney Transplantation - mortality ; Kidney Transplantation - physiology ; Male ; Medical sciences ; Middle Aged ; Mycophenolic Acid - analogs &amp; derivatives ; Mycophenolic Acid - therapeutic use ; Pancreas Transplantation - immunology ; Pancreas Transplantation - mortality ; Pancreas Transplantation - physiology ; Pharmacology. Drug treatments ; Retrospective Studies ; Sirolimus - therapeutic use ; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases ; Survival Analysis ; Tacrolimus - therapeutic use ; Time Factors ; Tissue, organ and graft immunology ; Treatment Outcome</subject><ispartof>Transplantation, 2007-05, Vol.83 (10), p.1324-1329</ispartof><rights>2007 INIST-CNRS</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c458t-7e16be6f536b24999a4fd32c2a1be8561840756d8df3334ab45658ece62e635a3</citedby><cites>FETCH-LOGICAL-c458t-7e16be6f536b24999a4fd32c2a1be8561840756d8df3334ab45658ece62e635a3</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>314,776,780,27901,27902</link.rule.ids><backlink>$$Uhttp://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&amp;idt=18798028$$DView record in Pascal Francis$$Hfree_for_read</backlink><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/17519781$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>GALLON, Lorenzo G</creatorcontrib><creatorcontrib>WINOTO, Johan</creatorcontrib><creatorcontrib>CHHABRA, Darshika</creatorcontrib><creatorcontrib>PARKER, Michele A</creatorcontrib><creatorcontrib>LEVENTHAL, Joseph R</creatorcontrib><creatorcontrib>KAUFMAN, Dixon B</creatorcontrib><title>Long-term renal transplant function in recipient of simultaneous kidney and pancreas transplant maintained with two prednisone-free maintenance immunosuppressive combinations: Tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus</title><title>Transplantation</title><addtitle>Transplantation</addtitle><description>It is not known how different steroid-free immunosuppressive combinations affect long-term kidney transplant function in recipients of simultaneous kidney and pancreas transplant (SPK). Here, we sought to evaluate, in SPK recipients, the impact on long-term renal allograft function of two Tac-based prednisone-free maintenance immunosuppressive protocols: tacrolimus (Tac)/mycophonelate mofetil (MMF) versus Tac/ sirolimus (SRL). In this single-center, retrospective, sequential study, we analyzed 59 SPK transplant patients with at median follow up of 5 years. All patients received induction therapy with thymoglobulin and maintenance immunosuppression with Tac/MMF (n=22) or Tac/SRL (n=37). There were no differences between the two groups in regards to age, gender, race, panel reactive antibodies, degree of mismatch, donor age, incidence of delay graft function, and Tac trough levels at different time points after transplantation. Kaplan-Meier patient survival at 6 years after transplantation was not statistically different between the two groups. Rate of ACR was similar. Kidney survival, even if not statistically significant, was better in the Tac/MMF group than in the Tac/SRL (90.7% vs. 70.7%, P=0.09). The slope of glomerular filtration rate decline per month at 5 years after transplantation was not statistically different between the two groups. Both groups had the same decline over time in glomerular filtration rate of 0.40+/-0.06 mL/min/1.73/month. Pancreas survival at 6 years after transplantation was 100% in both treatment groups. Our data suggest that, in SPK recipients, long-term kidney allograft survival and function are not statistically different. A trend toward an increased rate of renal allograft loss was found in the Tac/SRL-treated group.</description><subject>Adult</subject><subject>Antibiotics. Antiinfectious agents. Antiparasitic agents</subject><subject>Antiviral agents</subject><subject>Biological and medical sciences</subject><subject>Cohort Studies</subject><subject>Drug Therapy, Combination</subject><subject>Female</subject><subject>Follow-Up Studies</subject><subject>Fundamental and applied biological sciences. Psychology</subject><subject>Fundamental immunology</subject><subject>Graft Rejection - epidemiology</subject><subject>Graft Survival</subject><subject>Humans</subject><subject>Immunosuppressive Agents - therapeutic use</subject><subject>Kidney Transplantation - immunology</subject><subject>Kidney Transplantation - mortality</subject><subject>Kidney Transplantation - physiology</subject><subject>Male</subject><subject>Medical sciences</subject><subject>Middle Aged</subject><subject>Mycophenolic Acid - analogs &amp; derivatives</subject><subject>Mycophenolic Acid - therapeutic use</subject><subject>Pancreas Transplantation - immunology</subject><subject>Pancreas Transplantation - mortality</subject><subject>Pancreas Transplantation - physiology</subject><subject>Pharmacology. Drug treatments</subject><subject>Retrospective Studies</subject><subject>Sirolimus - therapeutic use</subject><subject>Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases</subject><subject>Survival Analysis</subject><subject>Tacrolimus - therapeutic use</subject><subject>Time Factors</subject><subject>Tissue, organ and graft immunology</subject><subject>Treatment Outcome</subject><issn>0041-1337</issn><issn>1534-6080</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2007</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNqFks-O1SAYxRujce6MvoLBhe7agfLfnZnoaHITN-O6ofSrg7ZQgc7kvrMPIdfb5LobEgKBH-c7wKmqtwQ3BGt5jUmTlwaX1gpGlG64oi1rNHlW7QinrBZY4efVDmNGakKpvKguU_pZeE6lfFldEMmJlorsqj_74H_UGeKMIngzoRyNT8tkfEbj6m12wSPny6Z1i4OyGkaU3LxO2XgIa0K_3ODhgIwf0GK8jWDS_yKzcT6XDgN6dPke5ceAlgiDdyl4qMcIcGJKdW8BuXlefUjrUqCU3AMgG-beeXN0kj6gO2NjmIqBdD0fbFjuwYfJ5CISRshuQg8QU7GVz1xy2-xV9WI0U4LX23hVff_86e7mS73_dvv15uO-toyrXEsgogcxcir6lmmtDRsH2trWkB4UF0QxLLkY1DBSSpnpGRdcgQXRgqDc0Kvq_Ul3ieH3Cil3s0sWpun0ZJ3EvGUKkyfBFgshJdNPgkQLTSVrC6hPYLl9ShHGboluNvHQEdwdw9Nh0uWlO4en-xeeTh_dvNmKrP0Mw_nklpYCvNsAk6yZxvLL1qUzp6RWuFX0L3KE12s</recordid><startdate>20070527</startdate><enddate>20070527</enddate><creator>GALLON, Lorenzo G</creator><creator>WINOTO, Johan</creator><creator>CHHABRA, Darshika</creator><creator>PARKER, Michele A</creator><creator>LEVENTHAL, Joseph R</creator><creator>KAUFMAN, Dixon B</creator><general>Lippincott</general><scope>IQODW</scope><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7T5</scope><scope>H94</scope><scope>7X8</scope></search><sort><creationdate>20070527</creationdate><title>Long-term renal transplant function in recipient of simultaneous kidney and pancreas transplant maintained with two prednisone-free maintenance immunosuppressive combinations: Tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus</title><author>GALLON, Lorenzo G ; WINOTO, Johan ; CHHABRA, Darshika ; PARKER, Michele A ; LEVENTHAL, Joseph R ; KAUFMAN, Dixon B</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c458t-7e16be6f536b24999a4fd32c2a1be8561840756d8df3334ab45658ece62e635a3</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2007</creationdate><topic>Adult</topic><topic>Antibiotics. Antiinfectious agents. Antiparasitic agents</topic><topic>Antiviral agents</topic><topic>Biological and medical sciences</topic><topic>Cohort Studies</topic><topic>Drug Therapy, Combination</topic><topic>Female</topic><topic>Follow-Up Studies</topic><topic>Fundamental and applied biological sciences. Psychology</topic><topic>Fundamental immunology</topic><topic>Graft Rejection - epidemiology</topic><topic>Graft Survival</topic><topic>Humans</topic><topic>Immunosuppressive Agents - therapeutic use</topic><topic>Kidney Transplantation - immunology</topic><topic>Kidney Transplantation - mortality</topic><topic>Kidney Transplantation - physiology</topic><topic>Male</topic><topic>Medical sciences</topic><topic>Middle Aged</topic><topic>Mycophenolic Acid - analogs &amp; derivatives</topic><topic>Mycophenolic Acid - therapeutic use</topic><topic>Pancreas Transplantation - immunology</topic><topic>Pancreas Transplantation - mortality</topic><topic>Pancreas Transplantation - physiology</topic><topic>Pharmacology. Drug treatments</topic><topic>Retrospective Studies</topic><topic>Sirolimus - therapeutic use</topic><topic>Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases</topic><topic>Survival Analysis</topic><topic>Tacrolimus - therapeutic use</topic><topic>Time Factors</topic><topic>Tissue, organ and graft immunology</topic><topic>Treatment Outcome</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>GALLON, Lorenzo G</creatorcontrib><creatorcontrib>WINOTO, Johan</creatorcontrib><creatorcontrib>CHHABRA, Darshika</creatorcontrib><creatorcontrib>PARKER, Michele A</creatorcontrib><creatorcontrib>LEVENTHAL, Joseph R</creatorcontrib><creatorcontrib>KAUFMAN, Dixon B</creatorcontrib><collection>Pascal-Francis</collection><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>Immunology Abstracts</collection><collection>AIDS and Cancer Research Abstracts</collection><collection>MEDLINE - Academic</collection><jtitle>Transplantation</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>GALLON, Lorenzo G</au><au>WINOTO, Johan</au><au>CHHABRA, Darshika</au><au>PARKER, Michele A</au><au>LEVENTHAL, Joseph R</au><au>KAUFMAN, Dixon B</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Long-term renal transplant function in recipient of simultaneous kidney and pancreas transplant maintained with two prednisone-free maintenance immunosuppressive combinations: Tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus</atitle><jtitle>Transplantation</jtitle><addtitle>Transplantation</addtitle><date>2007-05-27</date><risdate>2007</risdate><volume>83</volume><issue>10</issue><spage>1324</spage><epage>1329</epage><pages>1324-1329</pages><issn>0041-1337</issn><eissn>1534-6080</eissn><coden>TRPLAU</coden><abstract>It is not known how different steroid-free immunosuppressive combinations affect long-term kidney transplant function in recipients of simultaneous kidney and pancreas transplant (SPK). Here, we sought to evaluate, in SPK recipients, the impact on long-term renal allograft function of two Tac-based prednisone-free maintenance immunosuppressive protocols: tacrolimus (Tac)/mycophonelate mofetil (MMF) versus Tac/ sirolimus (SRL). In this single-center, retrospective, sequential study, we analyzed 59 SPK transplant patients with at median follow up of 5 years. All patients received induction therapy with thymoglobulin and maintenance immunosuppression with Tac/MMF (n=22) or Tac/SRL (n=37). There were no differences between the two groups in regards to age, gender, race, panel reactive antibodies, degree of mismatch, donor age, incidence of delay graft function, and Tac trough levels at different time points after transplantation. Kaplan-Meier patient survival at 6 years after transplantation was not statistically different between the two groups. Rate of ACR was similar. Kidney survival, even if not statistically significant, was better in the Tac/MMF group than in the Tac/SRL (90.7% vs. 70.7%, P=0.09). The slope of glomerular filtration rate decline per month at 5 years after transplantation was not statistically different between the two groups. Both groups had the same decline over time in glomerular filtration rate of 0.40+/-0.06 mL/min/1.73/month. Pancreas survival at 6 years after transplantation was 100% in both treatment groups. Our data suggest that, in SPK recipients, long-term kidney allograft survival and function are not statistically different. A trend toward an increased rate of renal allograft loss was found in the Tac/SRL-treated group.</abstract><cop>Hagerstown, MD</cop><pub>Lippincott</pub><pmid>17519781</pmid><doi>10.1097/01.tp.0000264189.58324.91</doi><tpages>6</tpages><oa>free_for_read</oa></addata></record>
fulltext fulltext
identifier ISSN: 0041-1337
ispartof Transplantation, 2007-05, Vol.83 (10), p.1324-1329
issn 0041-1337
1534-6080
language eng
recordid cdi_proquest_miscellaneous_70524801
source MEDLINE; Journals@Ovid Complete
subjects Adult
Antibiotics. Antiinfectious agents. Antiparasitic agents
Antiviral agents
Biological and medical sciences
Cohort Studies
Drug Therapy, Combination
Female
Follow-Up Studies
Fundamental and applied biological sciences. Psychology
Fundamental immunology
Graft Rejection - epidemiology
Graft Survival
Humans
Immunosuppressive Agents - therapeutic use
Kidney Transplantation - immunology
Kidney Transplantation - mortality
Kidney Transplantation - physiology
Male
Medical sciences
Middle Aged
Mycophenolic Acid - analogs & derivatives
Mycophenolic Acid - therapeutic use
Pancreas Transplantation - immunology
Pancreas Transplantation - mortality
Pancreas Transplantation - physiology
Pharmacology. Drug treatments
Retrospective Studies
Sirolimus - therapeutic use
Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases
Survival Analysis
Tacrolimus - therapeutic use
Time Factors
Tissue, organ and graft immunology
Treatment Outcome
title Long-term renal transplant function in recipient of simultaneous kidney and pancreas transplant maintained with two prednisone-free maintenance immunosuppressive combinations: Tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus
url https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-04T12%3A19%3A29IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Long-term%20renal%20transplant%20function%20in%20recipient%20of%20simultaneous%20kidney%20and%20pancreas%20transplant%20maintained%20with%20two%20prednisone-free%20maintenance%20immunosuppressive%20combinations:%20Tacrolimus/mycophenolate%20mofetil%20versus%20tacrolimus/sirolimus&rft.jtitle=Transplantation&rft.au=GALLON,%20Lorenzo%20G&rft.date=2007-05-27&rft.volume=83&rft.issue=10&rft.spage=1324&rft.epage=1329&rft.pages=1324-1329&rft.issn=0041-1337&rft.eissn=1534-6080&rft.coden=TRPLAU&rft_id=info:doi/10.1097/01.tp.0000264189.58324.91&rft_dat=%3Cproquest_cross%3E70524801%3C/proquest_cross%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=19693742&rft_id=info:pmid/17519781&rfr_iscdi=true