subject:(MMP inhibition)

University of Lund

1. Rehn, Martin. Experimental Colonic Obstruction and Anastomotic Healing.

Degree: 2012, University of Lund

URL: https://lup.lub.lu.se/record/2299871 ; https://portal.research.lu.se/ws/files/3661064/2299872.pdf

Colorectal cancer is one of the most common malignant diseases world-wide. Most patients can be diagnosed, staged and treated by surgery in an elective setting. However, about one fifth of the patients will have an emergency presentation and in most cases due to malignant obstruction of the left colon. Immediate resection and anastomosis is feasible but carries a 3-fold higher risk of developing anastomotic leakage compared to elective surgery. Anastomotic healing in patients can be evaluated as clinical outcome and related to preoperative or peroperative patient factors. Experimental research renders it possible to study biochemical factors and cellular events during the course of healing. Previous research in the field of anastomotic healing has suggested a potential role for tissue-degrading enzymes on the loss of collagen in the proximity of an anastomosis leaving it vulnerable to dehiscence. The work presented in this thesis is mainly based on an established model of colonic obstruction in rat. It was found that already 24 hours after initiation of obstruction the collagen levels, analyzed as hydroxyproline, were substantially depressed proximal to the stenosis. On the other hand, the intestine had the capability to recover after relief of the obstruction since hydroxyproline levels were found to return to normal levels. The parallel in the clinical situation would be stenting of an obstruction as a bridge-to-surgery. The activity of matrix metalloproteinases is upregulated in obstructed rat colon and an anastomosis in this condition carries a high risk of leakage. The effect of a MMP inhibitor was investigated but was, contrary to expected, found to deteriorate the anastomoses. On the other hand, if an inhibitor could be delivered locally, improved healing could possibly be expected without unwanted effects, since breaking strength was increased with coated sutures in normal colon.

Subjects/Keywords: Surgery; Obstruction; anastomosis; colon; wound healing; matrix metalloproteinases; collagen; MMP inhibition

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APA (6^th Edition):

Rehn, M. (2012). Experimental Colonic Obstruction and Anastomotic Healing. (Doctoral Dissertation). University of Lund. Retrieved from https://lup.lub.lu.se/record/2299871 ; https://portal.research.lu.se/ws/files/3661064/2299872.pdf

Chicago Manual of Style (16^th Edition):

Rehn, Martin. “Experimental Colonic Obstruction and Anastomotic Healing.” 2012. Doctoral Dissertation, University of Lund. Accessed March 06, 2021. https://lup.lub.lu.se/record/2299871 ; https://portal.research.lu.se/ws/files/3661064/2299872.pdf.

MLA Handbook (7^th Edition):

Rehn, Martin. “Experimental Colonic Obstruction and Anastomotic Healing.” 2012. Web. 06 Mar 2021.

Vancouver:

Rehn M. Experimental Colonic Obstruction and Anastomotic Healing. [Internet] [Doctoral dissertation]. University of Lund; 2012. [cited 2021 Mar 06]. Available from: https://lup.lub.lu.se/record/2299871 ; https://portal.research.lu.se/ws/files/3661064/2299872.pdf.

Council of Science Editors:

Rehn M. Experimental Colonic Obstruction and Anastomotic Healing. [Doctoral Dissertation]. University of Lund; 2012. Available from: https://lup.lub.lu.se/record/2299871 ; https://portal.research.lu.se/ws/files/3661064/2299872.pdf

2. Boräng, Jennifer. Green tea inhibits proteolytic enzymes in GCF from patients with chronic periodontitis.

Degree: 2012, , Faculty of Odontology (OD)

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19944

Kronisk parodontit orsakar vävnadsdestruktion till följd av matrixmetalloproteinasaktivitet. Dessa enzym härrör från värdcellerna och är en del av det immunologiska svaret på bakteriella virulensfaktorer. Grönt te har studerats för sina hälsofrämjande egenskaper, som omfattar bland annat anti-inflammatoriska effekter. Effekten beror delvis på enzyminhibering av tepolyfenoler. Syftet med denna studie var att ytterligare undersöka den inhiberande effekten av grönt te, med fokus på enzymatisk aktivitet i gingivalvätska från patienter med parodontal sjukdom. Patienter med kronisk parodontit valdes ut för att delta i studien. Gingivalvätska extraherades med mikropipetter från patienternas gingivala sulci. Proverna behandlades med grönt te och jämfördes med obehandlade prover från samma försöksperson. Fluorescens proteasanalys med kasein som substrat utfördes på fjorton prover för att detektera skillnader i kaseinolytisk aktivitet. Zymogramanalys med användning av gelatin som substrat utfördes på fyra prover, för att undersöka skillnader i gelatinolytisk aktivitet och analysera molekylvikter för de olika enzymerna. Den fluorometriska analysen visade en signifikant lägre enzymaktivitet i prover med tillsatt grönt te jämfört med obehandlade prover (p<0.001). Zymogramanalysen visade en skillnad i enzymaktivitet som var mest uttalad i banden för molekylär vikt runt 255 kDa, analogt med komplex av matrixmetalloproteinas-9. Sammanfattningsvis har det i denna studie påvisats att grönt te har en hämmande effekt på kaseinolytisk aktivitet och en mindre, mer specifik, hämmande effekt på gelatinasaktivitet.

Chronic periodontitis involves tissue destruction by matrix metalloproteinase, derived from the host cells, as part of the immunological response to bacterial virulence factors. Green tea has been studied for its health promoting properties, which includes anti-inflammatory effects. The effect is in part due to enzyme inhibition by tea polyphenols. The aim of this study was to further investigate the inhibitory effect of green tea, focusing on enzymatic activity in gingival crevicular fluid from patients with periodontal disease. Patients with chronic periodontitis were selected for participation in the study. Gingival crevicular fluid was extracted with micropipettes from the gingival sulci of the patients. Samples were treated with green tea and compared with untreated samples from the same subject. Fluorescence protease assay with casein as substrate was made using fourteen samples for detecting differences in caseinolytic activity. Zymogram assay using gelatin as substrate was done using four samples to test gelatinolytic activity and analyse molecular weights of the different enzymes. The fluorometric assay showed a significantly lower enzyme activity in samples mixed with green tea than untreated samples (p<0.001). The zymogram assay showed a difference in band strength which was most pronounced in the bands of molecular weight around 255 kDA, analogous to complexes of matrix metalloproteinase-9. In conclusion,…

Subjects/Keywords: green tea; polyphenols; EGCg; GCF; gingival crevicular fluid; periodontitis; MMP; inhibition; enzyme; fluorescence assay; zymography; Medical and Health Sciences; Medicin och hälsovetenskap

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APA (6^th Edition):

Boräng, J. (2012). Green tea inhibits proteolytic enzymes in GCF from patients with chronic periodontitis. (Thesis). , Faculty of Odontology (OD). Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19944

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Boräng, Jennifer. “Green tea inhibits proteolytic enzymes in GCF from patients with chronic periodontitis.” 2012. Thesis, , Faculty of Odontology (OD). Accessed March 06, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19944.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Boräng, Jennifer. “Green tea inhibits proteolytic enzymes in GCF from patients with chronic periodontitis.” 2012. Web. 06 Mar 2021.

Vancouver:

Boräng J. Green tea inhibits proteolytic enzymes in GCF from patients with chronic periodontitis. [Internet] [Thesis]. , Faculty of Odontology (OD); 2012. [cited 2021 Mar 06]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19944.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Boräng J. Green tea inhibits proteolytic enzymes in GCF from patients with chronic periodontitis. [Thesis]. , Faculty of Odontology (OD); 2012. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19944

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Talungchit, Supitcha. Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems.

Degree: PhD, Oral Science, 2012, University of Iowa

URL: https://ir.uiowa.edu/etd/2996

Current hydrophilic resin adhesives undergo hydrolytic degradation and show a decrease in bond strength over time. Nanoleakage and ultrastructure studies suggest that inadequately infiltrated collagen leads to enzymatic degradation and resin-dentin bond failure. Adequate degree of conversion (DC) of resin adhesives is also critical to resin-dentin bond strength and durability. The long-term goal of this dissertation is the realization of durable resin-dentin bond. It is hypothesized that ethanol-wet bonding technique (EW) may effectively facilitate the infiltration of hydrophobic monomers into hydrophilic acid-etched dentin by maintaining interfibrillar spacing, stiffening collagen matrix, and improving adhesive resin-demineralized dentin matrix miscibility. Chlorhexidine (CHX), Matrix Metalloproteinase-inhibitor (MMP-inhibitor), should further preserve collagen integrity and resin-dentin bond strength. Moreover, efficient photoinitiator systems that broaden light absorptivity and provide more reactive radicals may enhance polymerization. In this dissertation, a clinically-relevant EW protocol, 3×15s absolute ethanol rinsing, provided significantly higher microtensile bond strength (πTBS) of a hydrophobic resin (70%BisGMA/30%TEGDMA) to dentin as compared to water-wet bonding (WW). All groups showed no significant drop of πTBS after 1-year storage except EW without CHX application, showing marginally significant reduction in πTBS (p=0.0558) suggesting MMP-inhibition by CHX in EW. These results were consistent with subsequent experiments. EW maintained interfibrillar width and hybrid layer thickness for resin infiltration and retention. Monomer molar concentration across the hybrid layer was significantly higher in EW than WW. An application of 2% CHX diacetate further preserved collagen banding in EW. WW showed more generalized spotted nanoleakage, while EW presented localized reticular nanoleakage. The use of Irgacure 819 (BAPO) alone and in combination with benzoyl peroxide (BPO) or camphorquinone (CQ) increased DC of hydrophobic and hydrophilic resins over resins containing the CQ/amine (4E) control. Only BAPO and BAPO/BPO demonstrated significantly higher immediate shear bond strength than CQ/4E. Within the limitations of these studies, EW improved resin-dentin bond durability by maintaining collagen interfibrillar spaces for efficient infiltration of a hydrophobic BisGMA/TEGDMA resin resulting in significantly higher πTBS and monomer molar concentrations with less nanoleakage distribution within the hybrid layer than WW. CHX further maintained collagen integrity and πTBS in EW. BAPO is a potential… Advisors/Committee Members: Armstrong, Steven R. (supervisor).

Subjects/Keywords: Chlorhexidine; Dentin adhesion; Ethanol-wet bonding; MMP-inhibition; Photoinitiator; Resin adhesives; Oral Biology and Oral Pathology

…significant reduction in μTBS (p=0.0558) suggesting MMP-inhibition by CHX in EW. These… …inhibitor (MMP-inhibitor), should further preserve collagen integrity and resin-dentin… …105 Table 2-4 Weibull parameters by the type of combination of bonding substrate and MMP… …inhibition at same day… …108 Table 2-5 Weibull parameters by the type of combination of bonding substrate and MMP…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Talungchit, S. (2012). Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems. (Doctoral Dissertation). University of Iowa. Retrieved from https://ir.uiowa.edu/etd/2996

Chicago Manual of Style (16^th Edition):

Talungchit, Supitcha. “Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems.” 2012. Doctoral Dissertation, University of Iowa. Accessed March 06, 2021. https://ir.uiowa.edu/etd/2996.

MLA Handbook (7^th Edition):

Talungchit, Supitcha. “Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems.” 2012. Web. 06 Mar 2021.

Vancouver:

Talungchit S. Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems. [Internet] [Doctoral dissertation]. University of Iowa; 2012. [cited 2021 Mar 06]. Available from: https://ir.uiowa.edu/etd/2996.

Council of Science Editors:

Talungchit S. Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems. [Doctoral Dissertation]. University of Iowa; 2012. Available from: https://ir.uiowa.edu/etd/2996

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