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Thioguanine is effective as maintenance therapy for inflammatory bowel disease: a prospective multicentre registry study. J Crohns Colitis 2023:7005319. [PMID: 36702552 DOI: 10.1093/ecco-jcc/jjad013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Indexed: 01/28/2023]
Abstract
BACKGROUND AND AIMS Thioguanine is a well-tolerated and effective therapy for inflammatory bowel disease (IBD) patients. Prospective, effectiveness data are needed to substantiate the role of thioguanine as a maintenance therapy for IBD. METHODS IBD patients, who previously failed azathioprine or mercaptopurine, and initiated thioguanine were prospectively followed for 12 months starting when corticosteroid-free clinical remission was achieved (HBI ≤ 4 or SCCAI ≤ 2). Primary endpoint was corticosteroid-free clinical remission throughout 12 months. Loss of clinical remission was defined as SCCAI > 2 or HBI > 4, need of surgery, escalation of therapy, initiation of corticosteroids or study discontinuation. Additional endpoints were adverse events, drug survival, physician global assessment (PGA) and quality of life (QoL). RESULTS Sustained corticosteroid-free clinical remission at month 3, 6 or 12 months was observed in 75 (69%), 66 (61%) and 49 (45%) of 108 patients, respectively. Thioguanine was continued in 86 patients (80%) for at least 12 months. Loss of response (55%) included escalation to biologicals in 15%, corticosteroids in 10% and surgery in 3%. According to PGA scores, 82% of patients were still in remission after 12 months and QoL scores remained stable. Adverse events leading to discontinuation were reported in 11%, infections in 10%, myelo- and hepatotoxicity each in 6% and portal hypertension in 1% of patients. CONCLUSION Sustained corticosteroid-free clinical remission over 12 months was achieved in 45% of IBD patients on monotherapy with thioguanine. A drug continuation rate of 80%, together with favourable PGA and QoL scores, underlines the tolerability and effectiveness of thioguanine for IBD.
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Superior Effectiveness of Tofacitinib Compared to Vedolizumab in Anti-TNF-experienced Ulcerative Colitis Patients: A Nationwide Dutch Registry Study. Clin Gastroenterol Hepatol 2023; 21:182-191.e2. [PMID: 35644343 DOI: 10.1016/j.cgh.2022.04.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/21/2022] [Accepted: 04/29/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Clinicians face difficulty in when and in what order to position biologics and Janus kinase inhibitors in patients with anti-tumor necrosis factor-alpha (TNF) refractory ulcerative colitis (UC). We aimed to compare the effectiveness and safety of vedolizumab and tofacitinib in anti-TNF-exposed patients with UC in our prospective nationwide Initiative on Crohn and Colitis Registry. METHODS Patients with UC who failed anti-TNF treatment and initiated vedolizumab or tofacitinib treatment were identified in the Initiative on Crohn and Colitis Registry in the Netherlands. We selected patients with both clinical as well as biochemical or endoscopic disease activity at initiation of therapy. Patients previously treated with vedolizumab or tofacitinib were excluded. Corticosteroid-free clinical remission (Simple Clinical Colitis Activity Index ≤2), biochemical remission (C-reactive protein ≤5 mg/L or fecal calprotectin ≤250 μg/g), and safety outcomes were compared after 52 weeks of treatment. Inverse propensity score-weighted comparison was used to adjust for confounding and selection bias. RESULTS Overall, 83 vedolizumab- and 65 tofacitinib-treated patients were included. Propensity score-weighted analysis showed that tofacitinib-treated patients were more likely to achieve corticosteroid-free clinical remission and biochemical remission at weeks 12, 24, and 52 compared with vedolizumab-treated patients (odds ratio [OR], 6.33; 95% confidence interval [CI], 3.81-10.50; P < .01; OR, 3.02; 95% CI, 1.89-4.84; P < .01; and OR, 1.86; 95% CI, 1.15-2.99; P = .01; and OR, 3.27; 95% CI, 1.96-5.45; P < .01; OR, 1.87; 95% CI, 1.14-3.07; P = .01; and OR, 1.81; 95% CI, 1.06-3.09; P = .03, respectively). There was no difference in infection rate or severe adverse events. CONCLUSIONS Tofacitinib was associated with superior effectiveness outcomes compared with vedolizumab in anti-TNF-experienced patients with UC along with comparable safety outcomes.
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Immunomodulator Withdrawal From Anti-TNF Therapy Is Not Associated With Loss of Response in Inflammatory Bowel Disease. Clin Gastroenterol Hepatol 2022; 20:2577-2587.e6. [PMID: 35101632 DOI: 10.1016/j.cgh.2022.01.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 01/11/2022] [Accepted: 01/17/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS The benefit of concomitant immunomodulators (thiopurines or methotrexate) in patients with inflammatory bowel disease (IBD) on anti-tumor necrosis factor α (anti-TNF) (infliximab or adalimumab) maintenance therapy is debated. We compared outcomes after immunomodulator withdrawal vs continuation of combination therapy. METHODS This was a retrospective cohort study in a general hospital and a tertiary referral center. We included adult IBD patients, receiving anti-TNF therapy for ≥4 months, plus an immunomodulator at baseline, between January 1, 2011, and January 1, 2019. The primary endpoints were loss of response (LOR) (ie, anti-TNF discontinuation because of disease activity) and anti-drug antibodies. Adjusted hazard ratios (aHRs) were calculated by mixed-effects Cox regression analysis. RESULTS We included 614 treatment episodes of combination therapy in 543 individuals, yielding 1664 patient-years of follow-up. The immunomodulator was withdrawn in 296 (48.2%) episodes after 0.9 (interquartile range, 0.6-2.1) years, which was not associated with a higher risk of LOR (aHR, 1.08; 95% confidence interval [CI], 0.72-1.61), although anti-drug antibodies were detected more frequently (aHR, 2.14; 95% CI, 1.17-3.94), compared with continuation. Clinical remission at the time of withdrawal reduced the risk of LOR (aHR, 0.48; 95% CI, 0.25-0.93), while longer duration of combination therapy before withdrawal decreased the risk of anti-drug antibodies (HR per year, 0.56; 95% CI, 0.32-0.91). Higher prewithdrawal infliximab trough levels reduced the subsequent risks of anti-drug antibodies and LOR. Infliximab trough levels were lower after immunomodulator withdrawal (P = .01). CONCLUSIONS Patients who withdrew the immunomodulator in this retrospective cohort were not at increased risk of LOR within the following 1-2 years, but an increase in anti-drug antibodies was observed. Our findings require prospective validation, preferably in adequately powered randomized controlled trials.
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Response of Ti microstructure in mechanical and laser forming processes. JOURNAL OF MATERIALS SCIENCE 2018; 53:14713-14728. [PMID: 30956349 PMCID: PMC6428275 DOI: 10.1007/s10853-018-2650-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 06/27/2018] [Indexed: 06/09/2023]
Abstract
Microstructural deformation mechanisms present during three different forming processes in commercially pure Ti were analysed. Room temperature mechanical forming, laser beam forming and a combination of these two processes were applied to thick metal plates in order to achieve the same final shape. An electron backscatter diffraction technique was used to study the plate microstructure before and after applying the forming processes. Substantial differences among the main deformation mechanisms were clearly detected. In pure mechanical forming at room temperature, mechanical twinning predominates in both compression and tensile areas. A dislocation slip mechanism inside the compression and tensile area is characteristic of the pure laser forming process. Forming processes which subsequently combine the laser and mechanical approaches result in a combination of twinning and dislocation mechanisms. The Schmid factor at an individual grain level, the local temperature and the strain rate are factors that determine which deformation mechanism will prevail at the microscopic level. The final microstructures obtained after the different forming processes were applied are discussed from the point of view of their influence on the performance of the resulting formed product. The observations suggest that phase transformation in Ti is an additional microstructural factor that has to be considered during laser forming.
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Acute and Long-Term Effects of Full-Power Electroporation Ablation Directly on the Porcine Esophagus. Circ Arrhythm Electrophysiol 2017; 10:CIRCEP.116.004672. [DOI: 10.1161/circep.116.004672] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 04/17/2017] [Indexed: 12/18/2022]
Abstract
Background—
Esophageal ulceration and fistula are complications of pulmonary vein isolation using thermal energy sources. Irreversible electroporation is a novel, nonthermal ablation modality for pulmonary vein isolation. A single 200 J application can create deep myocardial lesions. Acute and chronic effects of this new energy source on the esophagus are unknown.
Methods and Results—
In 8 pigs (±70 kg), the suprasternal esophagus was surgically exposed. A linear suction device with a single 35-mm long and 6-mm wide protruding linear electrode inside a plastic suction cup was used for ablation. Single, nonarcing, nonbarotraumatic, cathodal 100 and 200 J applications were delivered at 2 different sites on the anterior esophageal adventitia. No proton-pump inhibitors were administered during follow-up. Esophagoscopy was performed at days 2 and 7. After euthanasia at day 60, the esophagus was evaluated visually and histologically. All ablations were uneventful. Esophagoscopy at day 2 showed small white densities in the ablated areas, which appeared to be small intraepithelial vesicles. No epithelial erythema, erosions, or ulcerations were seen. At day 7, all densities had disappeared, and all esophaguses appeared completely normalized. After euthanasia, there were no macroscopically visible lesions on the adventitia or epithelium. Histologically, a small scar was observed at the outer part of the muscular layer, whereas the mucosa and submucosa were normal.
Conclusions—
Esophageal architecture remains unaffected 2 months after irreversible electroporation, purposely targeting the adventitia. Irreversible electroporation seems to be a safe modality for catheter ablation near the esophagus.
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Cerebral magnetic resonance imaging in quiescent Crohn’s disease patients with fatigue. World J Gastroenterol 2017; 23:1018-1029. [PMID: 28246475 PMCID: PMC5311090 DOI: 10.3748/wjg.v23.i6.1018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/14/2016] [Accepted: 12/08/2016] [Indexed: 02/06/2023] Open
Abstract
AIM
To evaluate brain involvement in quiescent Crohn’s disease (CD) patients with fatigue using quantitative magnetic resonance imaging (MRI).
METHODS
Multiple MRI techniques were used to assess cerebral changes in 20 quiescent CD patients with fatigue (defined with at least 6 points out of an 11-point numeric rating scale compared with 17 healthy age and gender matched controls without fatigue. Furthermore, mental status was assessed by cognitive functioning, based on the neuropsychological inventory including the different domains global cognitive functioning, memory and executive functioning and in addition mood and quality of life scores. Cognitive functioning and mood status were correlated with MRI findings in the both study groups.
RESULTS
Reduced glutamate + glutamine (Glx = Glu + Gln) concentrations (P = 0.02) and ratios to total creatine (P = 0.02) were found in CD patients compared with controls. Significant increased Cerebral Blood Flow (P = 0.05) was found in CD patients (53.08 ± 6.14 mL/100 g/min) compared with controls (47.60 ± 8.62 mL/100 g/min). CD patients encountered significantly more depressive symptoms (P < 0.001). Cognitive functioning scores related to memory (P = 0.007) and executive functioning (P = 0.02) were lower in CD patients and both scores showed correlation with depression and anxiety. No correlation was found subcortical volumes between CD patients and controls in the T1-weighted analysis. In addition, no correlation was found between mental status and MRI findings.
CONCLUSION
This work shows evidence for perfusion, neurochemical and mental differences in the brain of CD patients with fatigue compared with healthy controls.
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AB0545 Magnetic resonance imaging of the hands and knees in patients with inflammatory bowel disease and arthralgia – a pilot study. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.2867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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FRI0466 Back pain and peripheral joint complaints in inflammatory bowel disease patients. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.1593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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FRI0465 Quality of life in inflammatory bowel disease patients with and without arthropathies: a prospective longitudinal study with 12-months follow-up. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.1592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Pretravel preparation and travel-related morbidity in patients with inflammatory bowel disease. Inflamm Bowel Dis 2012; 18:2079-85. [PMID: 22294313 DOI: 10.1002/ibd.22903] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Accepted: 01/09/2012] [Indexed: 01/16/2023]
Abstract
BACKGROUND There are no published data on health preparation and travel-related morbidity in patients with inflammatory bowel disease (IBD). METHODS A retrospective web-based questionnaire study on past travel experiences with more detailed questions concerning the most recent journey. Participants were recruited from the IBD outpatient clinic and via the website of the Dutch patient organization. RESULTS In all, 277 patients who had traveled abroad during the past 5 years (172 Crohn's disease, 105 ulcerative colitis) filled out the questionnaire. The majority (62%) answered that IBD limited their choice of travel destinations. Forty-three percent traveled to resource-limited destinations and 76% thereof obtained pretravel advice. Only 48% were prescribed an antibiotic for self-treatment in case of infectious diarrhea, and 23% were not protected against hepatitis A. Fecal urgency and incontinence were the main IBD-related inconveniences. Thirty-two percent reported a new episode of diarrhea and 28% thereof attributed it to an enteric infection. In total, 15/277 (5%) consulted a foreign physician, of whom five were admitted to hospital. Fifty-four (19%) had a self-reported exacerbation of IBD within 2 months following travel and 24% thereof attributed it to the recent travel. The Mantel-Haenszel odds ratio for an exacerbation within a 2-month period after travel was 1.1 (95% confidence interval [CI] 0.7-1.8) when the number of self-reported exacerbations in a 5-year period was used as reference and 1.5 (95% CI 0.9-2.6) when the year 2008 was used as reference. CONCLUSIONS Pretravel advice for IBD patients was often deficient. There was a considerable amount of travel-related morbidity and inconvenience.
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Results from the 2nd Scientific Workshop of the ECCO. I: Impact of mucosal healing on the course of inflammatory bowel disease. J Crohns Colitis 2011; 5:477-83. [PMID: 21939925 DOI: 10.1016/j.crohns.2011.06.009] [Citation(s) in RCA: 233] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 06/21/2011] [Indexed: 12/12/2022]
Abstract
Over the past years, mucosal healing has emerged as a major therapeutic goal in clinical trials in inflammatory bowel diseases. Accumulating evidence indicates that mucosal healing may change the natural course of the disease by decreasing the need for surgery and reducing hospitalization rates in both ulcerative colitis and Crohn's disease. Mucosal healing may also prevent the development of long-term disease complications, such as bowel damage in Crohn's disease and colorectal cancer in ulcerative colitis. Histologic healing may be the ultimate therapeutic goal in ulcerative colitis, whereas its impact on the course of Crohn's disease is unknown. Complete mucosal healing may be required before considering drug withdrawal. Targeting early Crohn's disease is more effective than approaches aimed at healing mucosa in longstanding disease. Several questions remain to be answered: should mucosal healing be systematically used in clinical practice? Should we optimize therapies to achieve mucosal healing? What is the degree of intestinal healing that is required to change the disease course? Large prospective studies addressing these issues are needed.
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Outcome of pregnancy in women with inflammatory bowel disease treated with antitumor necrosis factor therapy. Inflamm Bowel Dis 2011; 17:1846-54. [PMID: 21830263 DOI: 10.1002/ibd.21583] [Citation(s) in RCA: 121] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2010] [Accepted: 10/22/2010] [Indexed: 12/16/2022]
Abstract
BACKGROUND Infliximab (IFX) and adalimumab (ADA) are attractive treatment options in patients with inflammatory bowel disease (IBD) also during pregnancy but there is still limited data on the benefit/risk profile of IFX and ADA during pregnancy. METHODS This observational study assessed pregnancy outcomes in 212 women with IBD under antitumor necrosis factor alpha (TNF) treatment at our IBD unit. Pregnancy outcomes in 42 pregnancies with direct exposure to anti-TNF treatment (35 IFX, 7 ADA) were compared with that in 23 pregnancies prior to IBD diagnosis, 78 pregnancies before start of IFX, 53 pregnancies with indirect exposure to IFX, and 56 matched pregnancies in healthy women. RESULTS Thirty-two of the 42 pregnancies ended in live births with a median gestational age of 38 weeks (interquartile range [IQR] 37-39). There were seven premature deliveries, six children had low birth weight, and there was one stillbirth. One boy weighed 1640 g delivered at week 33, died at age of 13 days because of necrotizing enterocolitis. A total of eight abortions (one patient wish) occurred in seven women. Trisomy 18 was diagnosed in one fetus of a mother with CD at age 37 under ADA treatment (40 mg weekly) and pregnancy was terminated. Pregnancy outcomes after direct exposure to anti-TNF treatment were not different from those in pregnancies before anti-TNF treatment or with indirect exposure to anti-TNF treatment but outcomes were worse than in pregnancies before IBD diagnosis. CONCLUSIONS Direct exposure to anti-TNF treatment during pregnancy was not related to a higher incidence of adverse pregnancy outcomes than IBD overall.
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Levels of C-reactive protein are associated with response to infliximab therapy in patients with Crohn's disease. Clin Gastroenterol Hepatol 2011; 9:421-7.e1. [PMID: 21334460 DOI: 10.1016/j.cgh.2011.02.008] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Revised: 12/30/2010] [Accepted: 02/07/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Infliximab is an antibody against tumor necrosis factor-α that is used to treat patients with moderate to severe Crohn's disease (CD). C-reactive protein (CRP) is a marker used to identify and follow individuals with CD. We analyzed changes in levels of CRP in a large cohort of patients with CD undergoing treatment with infliximab. METHODS Serial levels of CRP were analyzed in 718 CD patients. Blood was collected before each infusion; a total of 8845 CRP levels were available for analysis. The correlations between CRP levels and need for dose adjustment, outcomes, and mucosal healing (based on endoscopic analysis of 253 patients) were evaluated. Therapy adjustment was considered successful if therapy continued without need for change. Subgroup analysis was performed by using data from 268 patients who received 8 weeks of maintenance therapy. RESULTS More patients with high baseline levels of CRP responded to infliximab than patients with normal levels (90.8% vs 82.6%; P = .014). Early normalization of CRP levels correlated with sustained long-term response (P < .001). CRP levels remained significantly higher among patients who lost their response to infliximab, compared with those with a sustained response (P = .001). At time of loss of response, CRP levels were significantly increased (median, 11.2 mg/L) and did not return to baseline levels (median, 18.2 mg/L; P = .039). CRP correlated with mucosal healing (P = .033). CONCLUSIONS CRP is a good marker of disease activity in patients treated with infliximab. Increased levels of CRP indicate mucosal inflammation and a likelihood of clinical relapse.
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Contrast-enhanced CT colonography with 64-slice MDCT compared to endoscopic colonoscopy in the follow-up of patients after colorectal cancer resection. Clin Imaging 2010; 33:433-8. [PMID: 19857803 DOI: 10.1016/j.clinimag.2009.01.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Accepted: 01/08/2009] [Indexed: 02/01/2023]
Abstract
BACKGROUND Seventy percent of newly diagnosed colorectal cancer cases are potential candidates for curative surgery, but after resection, in 30%, the tumor will recur. Postoperative follow-up includes endoscopic colonoscopy (EC) and computed tomography (CT). There have been only a few publications on the use of contrast-enhanced CT colonography (CECTC) in the follow-up of these patients. METHODS Twenty-nine consecutive patients after resection of colorectal cancer underwent CECTC and EC on the same day. CECTC studies were reviewed for identification of strictures, recurrence, polyps and metastases. RESULTS The anastomosis was identified in 96% of patients on CECTC and in 82% on endoscopic colonoscopy. One stricture was identified by both techniques. One extraluminal recurrence was depicted only on CECTC. Sensitivity in detecting polyps was per polyp 93% and per patient 100%. CONCLUSION CECTC performed on a 64-slice multidetector CT is reliable in imaging the postoperative colon for the follow-up of patients after resection of colorectal cancer.
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Mucosal healing predicts long-term outcome of maintenance therapy with infliximab in Crohn's disease. Inflamm Bowel Dis 2009; 15:1295-301. [PMID: 19340881 DOI: 10.1002/ibd.20927] [Citation(s) in RCA: 505] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Infliximab (IFX) treatment induces mucosal healing (MH) in patients with Crohn's disease (CD) but the impact of MH on the long-term outcome of IFX treatment in CD is still debated. METHODS We studied MH during long-term treatment with IFX in 214 CD patients. A total of 183 patients (85.5%) responded to induction therapy and 31 patients (14.5%) were primary nonresponders. They underwent lower gastrointestinal (GI) endoscopy within a median of 0.7 months (interquartile range [IQR] 0.1-6.8) prior to first IFX and after a median of 6.7 months (IQR 1.4-24.6) after start of IFX and were further analyzed. The relationship between the outcome of IFX treatment long-term and MH was studied. RESULTS MH was observed in 67.8% of the 183 initial responders (n = 124), with 83 patients having complete healing (45.4%) and 41 having partial healing (22.4%). Scheduled IFX treatment from the start resulted in MH more frequently (76.9% MH rate) than episodic treatment (61.0% MH rate; P = 0.0222, odds ratio [OR] 2.14, 95% confidence interval [CI] 1.11-4.12). Concomitant treatment with corticosteroids (CS) had a negative impact on MH (37.9% in patients with CS versus 63.2% in patients without CS; P = 0.021, OR 0.36, 95% CI 0.16-0.80). MH was associated with a significantly lower need for major abdominal surgery (MAS) during long-term follow-up (14.1% of patients with MH needed MAS versus 38.4% of patients without MH; P < 0.0001). CONCLUSIONS MH induced by long-term maintenance IFX treatment is associated with an improved long-term outcome of the disease especially with a lower need for major abdominal surgeries.
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Long-term outcome of treatment with infliximab in 614 patients with Crohn's disease: results from a single-centre cohort. Gut 2009; 58:492-500. [PMID: 18832518 DOI: 10.1136/gut.2008.155812] [Citation(s) in RCA: 419] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS This observational study assessed the long-term clinical benefit of infliximab (IFX) in 614 consecutive patients with Crohn's disease (CD) from a single centre during a median follow-up of 55 months (interquartile range (IQR) 27-83). METHODS The primary analysis looked at the proportion of patients with initial response to IFX who had sustained clinical benefit at the end of follow-up. The long-term effects of IFX on the course of CD as reflected by the rate of surgery and hospitalisations and need for corticosteroids were also analysed. RESULTS 10.9% of patients were primary non-responders to IFX. Sustained benefit was observed in 347 of the 547 patients (63.4%) receiving long-term treatment. In 68.3% of these, treatment with IFX was ongoing and in 31.7% IFX was stopped, with the patient being in remission. Seventy patients (12.8%) had to stop IFX due to side effects and 118 (21.6%) due to loss of response. Although the yearly drop-out rates of IFX in patients with episodic (10.7%) and scheduled treatment (7.1%) were similar, the need for hospitalisations and surgery decreased less in the episodic than in the scheduled group. Steroid discontinuation also occurred in a higher proportion of patients in the scheduled group than in the episodic group. CONCLUSIONS In this large real-life cohort of patients with CD, long-term treatment with IFX was very efficacious to maintain improvement during a median follow-up of almost 5 years and changed disease outcome by decreasing the rate of hospitalisations and surgery.
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Abstract
BACKGROUND AND AIMS This study evaluates the long-term safety of infliximab in patients with inflammatory bowel disease (IBD) treated with the drug over a 14-year period. METHODS The medical records of 734 patients with IBD treated with infliximab and 666 control patients not treated with infliximab were reviewed for adverse events. The time of onset and outcome, severity and concomitant medication were recorded. RESULTS Patients and controls were followed up for serious adverse events for a median time of 58 months (IQR 33-88) and 144 months (IQR 83-163), respectively. 112 severe adverse events occurred in 93 patients (13%) treated with infliximab and 157 occurred in 126 (19%) control patients (OR 1.33 (95% CI 0.56 to 3.00, p = 0.45). There was no difference between the two groups in mortality, malignancies and infection rate. Tuberculosis was diagnosed in two patients receiving infliximab who had negative skin tests at baseline whereas none of 16 patients with positive skin tests who received prophylaxis developed tuberculosis. Concomitant treatment with steroids was the only independent risk factor for infections in patients treated with infliximab (OR 2.69 (95% CI 1.18 to 6.12), p = 0.018). The most commonly observed systemic side effects were skin eruptions including psoriasiform eruptions in 150 patients (20%). CONCLUSIONS Long-term infliximab treatment had a good overall safety profile in the patient cohort studied.
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Long-term outcome after infliximab for refractory ulcerative colitis. J Crohns Colitis 2008; 2:219-25. [PMID: 21172214 DOI: 10.1016/j.crohns.2008.03.004] [Citation(s) in RCA: 167] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Accepted: 03/18/2008] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS Infliximab (IFX) has been shown efficacious for moderate-to-severe ulcerative colitis (UC), but data on long-term efficacy are lacking. We investigated long-term outcome including colectomy rates in outpatients treated with IFX for refractory UC in a single referral centre, and evaluated if predictors could be identified. METHODS The first 121 outpatients (median age 38.0 years) with refractory UC treated with IFX were included. The primary outcome was colectomy-free survival. Secondary measures were sustained clinical response and serious adverse events. RESULTS From the 81 patients (67%) with an initial clinical response to IFX, 68% had a sustained clinical response. No independent predictors of sustained clinical response could be identified. Over a median (IQR) follow-up period of 33.0 (17.0-49.8) months, 21 patients (17%) came to colectomy. Independent predictors of colectomy were absence of short-term clinical response [Hazard ratio 10.8 (95% CI 3.5-32.8), p<0.001], a baseline CRP level ≥5 mg/L [Hazard ratio 14.5 (95% CI 2.0-108.6), p=0.006] and previous IV treatment with corticosteroids and/or cyclosporine [Hazard ratio 2.4 (95% CI 1.1-5.9), p=0.033]. Six patients developed a serious infection, three a malignancy, two a post-operative complication and one patient died (suicide). CONCLUSIONS With a median follow-up of 33.0 months after start of IFX, 17% of patients with refractory UC needed colectomy, while sustained clinical response was present in 68% of initial responders.
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P016 FLEXIBILITY IN INTERVAL AND DOSING OF INFLIXIMAB ENABLES MAINTAINED RESPONSE OF PATIENTS WITH CROHN'S DISEASE. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s1873-9954(08)70027-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
OBJECTIVES Perianal disease (PD) is a frequent complication of Crohn's disease (CD). The lack of association between PD and development of intestinal penetrating disease may suggest that PD is a distinct phenotype with specific genetic or clinical risk factors. This study was undertaken to evaluate the role of genotype, clinical, and demographic characteristics with PD. METHODS Phenotypic data on 121 CD patients with PD and 179 patients without PD were carefully characterized. The patients were genotyped for disease-associated OCTN1/2 and NOD2/CARD15 variants and the TNF-alpha promoter polymorphisms. Analysis was performed to evaluate the differences in phenotype and genotype frequencies between the PD group and the non-PD group. RESULTS PD was associated with rectal involvement (odds ratio [OR] 2.27, 95% CI 1.32-3.91) and with Sephardic (non-Ashkenazi) Jewish ethnicity (OR 1.71, 95% CI 1.02-2.9). No association was found among the studied OCTN, NOD2, TNF-alpha variants and the risk for PD. CONCLUSIONS The strongest factor associated with PD is rectal inflammation. OCTN1/2, NOD2/CARD15, and TNF-alpha promoter variants do not play a role in the risk to PD in the Jewish Israeli population. The association of ethnicity with PD may suggest that there are as yet unknown genetic variants that are associated with PD.
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LONG-TERM OUTCOME OF TREATMENT WITH INFLIXIMAB IN 440 CROHN'S DISEASE PATIENTS: RESULTS FROM A SINGLE CENTER COHORT. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s1873-9954(07)70002-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
BACKGROUND Endoscopic ultrasound (EUS) has been shown to be a reliable tool for staging rectal cancer. Nevertheless, the accuracy of EUS after chemoradiation remains unclear; therefore the purpose of the present paper was to compare the accuracy of EUS staging for rectal cancer before and following chemoradiation. METHODS Patients with rectal cancer undergoing EUS staging were stratified into two groups. Group I consisted of 66 patients who underwent surgery following EUS staging without preoperative chemoradiation. Group II consisted of 25 patients who had EUS evaluation following chemoradiation. The EUS staging was compared to surgical/pathological staging. RESULTS The accuracy of the T staging for group I was 86% (57/66). Inaccurate staging was mainly associated with overstaging EUS T2 tumors. The accuracy of the N staging for group I was 71% (47/66). The accuracy of EUS for a composite T and N staging relevant to treatment decisions in group I was 91%. In group II, the accuracy of T and N staging was 72% (18/25) and 80% (20/25), respectively. Overstaging EUS T3 tumors accounted for most inaccurate staging. The EUS staging predicted post-chemoradiation T0N0 stage correctly in only 50% of cases. CONCLUSIONS Preoperative staging of rectal cancer by EUS is a useful modality in determining the need for preoperative chemoradiation. The EUS T staging following chemoradiation appears to be less accurate. Detection of complete response may be insufficient for selecting patients for limited surgical intervention.
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Increasing the infliximab dose is beneficial in Crohn's disease patients who responded to a lower dose and relapsed. Digestion 2006; 72:124-8. [PMID: 16172549 DOI: 10.1159/000088367] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2005] [Accepted: 05/04/2005] [Indexed: 02/04/2023]
Abstract
BACKGROUND Relapse after an initial response to infliximab therapy poses a problem for maintenance treatment. AIM To assess the effects of increasing the infliximab dosage in Crohn's disease (CD) patients who initially responded but flared during maintenance therapy. METHODS This was an observational study. Twelve CD patients with both inflammatory and fistulizing manifestations were included. All patients initially responded to 5 mg/kg of infliximab, relapsed during maintenance therapy, and were treated with 10 mg/kg. The Harvey-Bradshaw index, the fistula activity, and steroid use were assessed before and after treatment with the increased dose of infliximab. RESULTS The mean Harvey-Bradshaw index score after flare-up during treatment with 5 mg/kg of infliximab was 13.5+/-3.7. Treatment with 10 mg/kg, in a mean of 3.3 infusions, decreased the activity score to a mean of 8.8+/-2.5. Two patients were weaned off prednisone, and a reduced dose was possible in the other steroid-treated patients. CONCLUSIONS Increasing the infliximab dose may be beneficial in CD patients who initially responded to therapy, but relapsed during maintenance with the lower dosage.
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Abstract
OBJECTIVES Crohn's disease (CD) has been reported to be more frequent among non-Ashkenazi Jewish patients suffering from familial Mediterranean fever (FMF). Interestingly, functional similarities between the CD susceptibility gene (NOD2/CARD15) and the FMF gene (MEFV) have been described: both belong to the death domain containing protein family, important in the regulation of apoptosis, cytokine processing and inflammation. AIMS To investigate the prevalence of MEFV mutations in Jewish non-Ashkenazi CD patients and its putative effect on CD presentation. METHODS Germline DNA of 105 Israeli CD patients of non-Ashkenazi and mixed Ashkenazi-non-Ashkenazi ethnic background was analyzed for three most common MEFV mutations: M694V, V726A, and E148Q. Five patients (4.7%) with a clinical diagnosis of FMF were included. Data obtained from each patient included: age of onset, disease location, and behavior, the presence of extraintestinal manifestations of CD and therapeutic regimens. RESULTS The overall prevalence of mutation carriers among non-FMF-CD patients was 13% (13/100). A stricturing disease pattern was observed in 56% (10/18) of all carriers, FMF-CD, and non-FMF-CD patients, and in 25% (22/87) of noncarriers (OR: 3.7, 95% CI: 1.3-10.5, p= 0.015). The prevalence of fistulas was comparable in both groups. Extraintestinal manifestations were significantly more frequent among carriers than noncarriers (65%vs 32%, OR 3.9, 95% CI = 1.3-11.5, p= 0.015). No differences were observed in disease location and disease severity. CONCLUSIONS MEFV mutations are not associated with CD susceptibility, yet the presence of these mutations appears to be associated with a stricturing disease pattern and extraintestinal disease manifestations of CD.
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TOWARDS A QUANTUM MOLECULAR MEASUREMENT THEORY: STERN-GERLACH THOUGHT EXPERIMENTS AT THE INTERFACE OF HILBERT AND REAL SPACES. JOURNAL OF THE CHILEAN CHEMICAL SOCIETY 2004. [DOI: 10.4067/s0717-97072004000200002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Abstract
BACKGROUND AND STUDY AIMS Chronic abdominal pain is a common complaint and in many patients even an extensive work-up does not reveal the cause for the pain. Given Imaging wireless capsule endoscopy is a new method for visualization of the entire small bowel. The aim of our study was to determine the role of capsule endoscopy in the evaluation of patients with unexplained chronic abdominal pain. PATIENTS AND METHODS 20 patients with chronic abdominal pain of 6 - 96 months' duration were enrolled in the study. They had had an extensive diagnostic work-up which was negative. Capsule endoscopy was performed in all patients. RESULTS Imaging of the small intestine was excellent and the colon was reached in 16 patients. In 14 patients the study was completely normal; in six patients the procedure revealed findings which were considered to be clinically insignificant. All patients tolerated the capsule well and had no adverse effects. CONCLUSION Capsule endoscopy did not seem to have any significant clinical value in the evaluation of our patients with obscure chronic abdominal pain.
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Lidocaine inhibits secretion of IL-8 and IL-1beta and stimulates secretion of IL-1 receptor antagonist by epithelial cells. Clin Exp Immunol 2002; 127:226-33. [PMID: 11876744 PMCID: PMC1906346 DOI: 10.1046/j.1365-2249.2002.01747.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Lidocaine and related local anaesthetics have been shown to be effective in the treatment of ulcerative colitis (UC). However, the mechanisms underlying their therapeutic effect are poorly defined. Intestinal epithelial cells play an important role in the mucosal inflammatory response that leads to tissue damage in UC via the secretion of pro-inflammatory cytokines and chemokines. The aim of this study was to evaluate the direct immunoregulatory effect of lidocaine on pro-inflammatory cytokine and chemokine secretion from intestinal epithelial cells. HT-29 and Caco-2 cell lines were used as a model system and treated with lidocaine and related drugs. The expression of IL-8, IL-1beta and the IL-1 receptor antagonist (RA) were assessed by ELISA and quantification of mRNA. In further experiments, the effect of lidocaine on the secretion of IL-8 from freshly isolated epithelial cells stimulated with TNFalpha was tested. Lidocaine, in therapeutic concentrations, inhibited the spontaneous and TNFalpha-stimulated secretion of IL-8 and IL-1beta from HT-29 and Caco-2 cell lines in a dose-dependent manner. Similarly, suppression of IL-8 secretion was noted in the freshly isolated epithelial cells. Other local anaesthetics, bupivacaine and amethocaine, had comparable effects. Lidocaine stimulated the secretion of the anti-inflammatory molecule IL-1 RA. Both the inhibitory and the stimulatory effects of lidocaine involved regulation of transcription. The results imply that the therapeutic effect of lidocaine may be mediated, at least in part, by its direct effects on epithelial cells to inhibit the secretion of proinflammatory molecules on one hand while triggering the secretion of anti-inflammatory mediators on the other.
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Abstract
OBJECTIVES The risk for thrombotic events is increased in inflammatory bowel disease. The factors responsible for such a risk are poorly defined. Recently, an elevated homocysteine level is emerging as a risk factor for thrombosis. The aim of this study was to determine the levels of homocysteine in a well-characterized population of patients with Crohn's disease and to compare it to controls. METHODS The levels of homocysteine were determined in 105 well-characterized patients with Crohn's disease and 106 controls. The levels of folate and B12, which are involved in the metabolism of homocysteine were determined as well. Patients were treated with steroid preparations only. RESULTS Homocysteine levels were significantly elevated in the patient population. Elevated levels were correlated with both low B12 and folate levels, but folate deficiency turned out to be a more important factor. Low B12 levels were in correlation with the involvement of the terminal ileum. No correlation was found between homocysteine levels and either disease activity or involvement of the terminal ileum. CONCLUSIONS Homocysteine levels are increased in patients with Crohn's disease and this finding is inversely correlated with folate levels. Supplementation of folate to patients with Crohn's disease may be warranted.
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The natural course of upper gastrointestinal submucosal tumors: an endoscopic ultrasound survey. THE ISRAEL MEDICAL ASSOCIATION JOURNAL : IMAJ 2000; 2:430-2. [PMID: 10897232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
BACKGROUND Differentiating between benign and malignant submucosal tumors is difficult. Moreover, the natural course of benign-appearing SMTs is not clearly elucidated. OBJECTIVES To evaluate the natural course of upper gastrointestinal SMTs by endoscopic endosonography. METHODS We followed 25 consecutive patients with small (< 40 mm) SMTs for a mean period of 19 months. Evaluation included maximal tumor diameter, internal echo pattern, and outer margin of lesions. RESULTS Follow-up revealed no change in echo features in 24 of 25 patients (96%). In only one patient a homogenous hypoechoic smooth margin lesion converted to a non-homogenous tumor with an irregular outer margin. This lesion also increased in size from 30 to 38 mm. On surgical removal this tumor was found to be a stromal tumor with high malignant potential. CONCLUSIONS Most small SMTs do not change during a period of 19 months and a conservative policy of surveillance is warranted.
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Inhibition of vascular endothelial growth factor (VEGF)-induced endothelial cell proliferation by a peptide corresponding to the exon 7-encoded domain of VEGF165. J Biol Chem 1997; 272:31582-8. [PMID: 9395496 DOI: 10.1074/jbc.272.50.31582] [Citation(s) in RCA: 148] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Vascular endothelial growth factor (VEGF) is a potent mitogen for endothelial cells (EC) in vitro and a major regulator of angiogenesis in vivo. VEGF121 and VEGF165 are the most abundant of the five known VEGF isoforms. The structural difference between these two is the presence in VEGF165 of 44 amino acids encoded by exon 7 lacking in VEGF121. It was previously shown that VEGF165 and VEGF121 both bind to KDR/Flk-1 and Flt-1 but that VEGF165 binds in addition to a novel receptor (Soker, S., Fidder, H., Neufeld, G., and Klagsbrun, M. (1996) J. Biol. Chem. 271, 5761-5767). The binding of VEGF165 to this VEGF165-specific receptor (VEGF165R) is mediated by the exon 7-encoded domain. To investigate the biological role of this domain further, a glutathione S-transferase fusion protein corresponding to the VEGF165 exon 7-encoded domain was prepared. The fusion protein inhibited binding of 125I-VEGF165 to VEGF165R on human umbilical vein-derived EC (HUVEC) and MDA-MB-231 tumor cells. The fusion protein also inhibited significantly 125I-VEGF165 binding to KDR/Flk-1 on HUVEC but not on porcine EC which express KDR/Flk-1 alone. VEGF165 had a 2-fold higher mitogenic activity for HUVEC than did VEGF121. The exon 7 fusion protein inhibited VEGF165-induced HUVEC proliferation by 60% to about the level stimulated by VEGF121. Unexpectedly, the fusion protein also inhibited HUVEC proliferation in response to VEGF121. Deletion analysis revealed that a core inhibitory domain exists within the C-terminal 23-amino acid portion of the exon 7-encoded domain and that a cysteine residue at position 22 in exon 7 is critical for inhibition. It was concluded that the exon 7-encoded domain of VEGF165 enhances its mitogenic activity for HUVEC by interacting with VEGF165R and modulating KDR/Flk-1-mediated mitogenicity indirectly and that exon 7-derived peptides may be useful VEGF antagonists in angiogenesis-associated diseases.
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Characterization of novel vascular endothelial growth factor (VEGF) receptors on tumor cells that bind VEGF165 via its exon 7-encoded domain. J Biol Chem 1996; 271:5761-7. [PMID: 8621443 DOI: 10.1074/jbc.271.10.5761] [Citation(s) in RCA: 256] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Vascular endothelial growth factor (VEGF), a potent angiogenic factor, uses two receptor tyrosine kinases, FLK/KDR and FLT, to mediate its activities. We have cross-linked 125I-VEGF165 to the cell surface of various tumor cell lines and of human umbilical vein endothelial cells. High molecular mass (220 and 240 kDa) and/or lower molecular mass (165 and 175 kDa) labeled complexes were detected depending on the cell type. The 220- and 240-kDa labeled complexes were shown to contain FLT and FLK/KDR receptors, respectively. On the other hand, the 165- and 175-kDa complexes did not seem to contain FLK/KDR or FLT but instead appeared to contain novel VEGF receptors with relatively low molecular masses of approximately 120 and 130 kDa. These receptors were further characterized in breast cancer MDA MB 231 cells (231), which did not form the high molecular mass complexes and which did not express detectable amounts of flk/kdr or flt mRNA. The 231 cells displayed one VEGF165 binding site, with a Kd of 2.8 x 10(-10) M and 0.95 1.1 x 10(5) binding sites per cell. By comparison, human umbilical vein endothelial cells had two binding sites, one with a Kd of 7.5 x 10(-12) M, presumably FLK/KDR, and the other with a Kd of 2 x 10(-10) M, a value similar to the VEGF binding sites on 231 cells. These lower affinity/molecular mass receptors on 231 cells cross-linked 125I-VEGF165 but not 125I-VEGF121. Accordingly, exon 7 of VEGF, which encodes the 44 amino acids present in VEGF165 that are absent in VEGF121, was fused to glutathione S-transferase (GST). The GST-VEGF-exon 7 fusion protein bound to heparin-Sepharose with a similar affinity as VEGF165 and inhibited the binding of 125I-VEGF165 to 231 cells. Cross-linking of 125I-GST-VEGF-exon 7 to 231 cells resulted in the formation of 150- and 160-kDa labeled complexes that presumably contained the 120- and 130-kDa lower affinity/molecular mass VEGF165 receptors. It was concluded that certain tumor-derived cell lines express novel surface-associated receptors that selectively bind VEGF165 via the exon 7-encoded domain, which is absent in VEGF121.
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The Effect of Diagonal and Off-Diagonal Disorder on Optical Properties of Molecular Aggregates. ACTA ACUST UNITED AC 1992. [DOI: 10.1007/978-3-642-84771-4_74] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Resonance-light-scattering study and line-shape simulation of the J band. PHYSICAL REVIEW LETTERS 1991; 66:1501-1504. [PMID: 10043225 DOI: 10.1103/physrevlett.66.1501] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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