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1.
Usha Patel Manish Pandey Sadhana Kannan Tanuja A. Samant Poonam Gera Neha Mittal Swapnil Rane Asawari Patil Vanita Noronha Amit Joshi Vijay M. Patil Kumar Prabhash Manoj B. Mahimkar 《British journal of cancer》2020,123(12):1757
Background Anti-EGFR-based therapies have limited success in HNSCC patients. Predictive biomarkers are greatly needed to identify the patients likely to be benefited from these targeted therapies. Here, we present the prognostic and predictive association of biomarkers in HPV-negative locally advanced (LA) HNSCC patients.Methods Treatment-naive tumour tissue samples of 404 patients, a subset of randomised Phase 3 trial comparing cisplatin radiation (CRT) versus nimotuzumab plus cisplatin radiation (NCRT) were analysed to evaluate the expression of HIF1α, EGFR and pEGFR by immunohistochemistry and EGFR gene copy change by FISH. Progression-free survival (PFS), locoregional control (LRC) and overall survival (OS) were estimated by Kaplan–Meier method. Hazard ratios were estimated by Cox proportional hazard models.Results Baseline characteristics of the patients were balanced between two treatment groups (CRT vs NCRT) and were representative of the trial cohort. The median follow-up was of 39.13 months. Low HIF1α was associated with better PFS [HR (95% CI) = 0.62 (0.42–0.93)], LRC [HR (95% CI) = 0.56 (0.37–0.86)] and OS [HR (95% CI) = 0.63 (0.43–0.93)] in the CRT group. Multivariable analysis revealed HIF1α as an independent negative prognostic biomarker. For patients with high HIF1α, NCRT significantly improved the outcomes [PFS:HR (95% CI) = 0.55 (0.37–0.82), LRC:HR (95% CI) = 0.55 (0.36–0.85) and OS:HR (95% CI) = 0.54 (0.36–0.81)] compared to CRT. While in patients with low HIF1α, no difference in the clinical outcomes was observed between treatments. Interaction test suggested a predictive value of HIF1α for OS (P = 0.008).Conclusions High HIF1α expression is a predictor of poor clinical response to CRT in HPV-negative LA-HNSCC patients. These patients with high HIF1α significantly benefited with the addition of nimotuzumab to CRT.Clinical trial registration Registered with the Clinical Trial Registry of India (Trial registration identifier—CTRI/2014/09/004980).Subject terms: Tumour biomarkers, Head and neck cancer, Tumour biomarkers, Head and neck cancer, Predictive markers 相似文献
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Dr. Menon Raj Gopal M.Ch. AlDelamie Taha FRCS Valliathu John FRCS Zacharias Sunny FRCS Lawati Al Adil FRCS Venkatraman M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(3):173-177
Background Despite improving surgical techniques, treatment of heart valve disease in children remains controversial. Somatic growth
and adequate anticoagulation are of concern when children undergo valve replacement. We conducted this study to evaluate the
performance of valves in this age group.
Methods 42 children under the age of 13 years who underwent valve replacement were included in this study. Totally, 50 valves were
implanted in 42 patients: 48 were mechanical prostheses, two were bioprosthetic both in pulmonary position. 37 (74%) valves
were implanted in mitral position, 10 (20%) in aortic position, 1 (2%) in tricuspid position and 2 (4%) in pulmonary position.
Preoperatively, 14 (33,3%) patients were in New York Heart Association (NYHA) class IV, while 27 (64.2%) were in NYHA class
III.
Results There were 2 (4.7%) hospital deaths and 2 (4.7%) late deaths while 2 (4.7%) patients were lost to follow up. The mean follow
up period was 9.4 yrs. 35 (83.3%) patients are in NYHA Class I and free of all medications except warfarin. 3 (7.1%) patients
have undergone 5 successful pregnancies. The median INR was 2.23. Major thrombo-embolic episode occurred in 1 (2.3%) patient.
Conclusions In view of the problems of sizing, anticoagulation and need for re-operation at an early age, there is a reluctance to replace
valves in children. This study shows that despite these problems, valve replacement can be undertaken safely and successfully
in children, when repair has failed or not technically feasible. 相似文献
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In-vitro/in-vivo correlation of pulsatile drug release from press-coated tablet formulations: a pharmacoscintigraphic study in the beagle dog. 总被引:1,自引:0,他引:1
Manish Ghimire Fiona J McInnes David G Watson Alexander B Mullen Howard N E Stevens 《European journal of pharmaceutics and biopharmaceutics》2007,67(2):515-523
The aim of the current study was to investigate the in-vitro and in-vivo performance of a press-coated tablet (PCT) intended for time delayed drug release, consisting of a rapidly disintegrating theophylline core tablet, press-coated with barrier granules containing glyceryl behenate (GB) and low-substituted hydroxypropylcellulose (L-HPC). The PCTs showed pulsatile release with a lag time dependent upon the GB and L-HPC composition of the barrier layer. In-vivo gamma-scintigraphic studies were carried out for PCTs containing GB:L-HPC at 65:35 w/w and 75:25 w/w in the barrier layer in four beagle dogs, in either the fed or fasted state. The in-vivo lag time in both the fed and fasted states did not differ significantly (p>0.05) from the in-vitro lag time. Additionally, no significant difference (p<0.05) between in-vivo fed and fasted disintegration times was observed, demonstrating that in-vivo performance of the PCT was not influenced by the presence or absence of food in the gastrointestinal tract. A distinct lag time was obtained prior to the appearance of drug in plasma and correlated (R2=0.98) with disintegration time observed from scintigraphic images. However, following disintegration, no difference in pharmacokinetic parameters (AUC(0-6 dis), K(el), Cmax) was observed. The current study highlighted the potential use of these formulations for chronopharmaceutical drug delivery. 相似文献
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Joseph G Rajendran Darrell R Fisher Ajay K Gopal Lawrence D Durack Oliver W Press Janet F Eary 《Journal of nuclear medicine》2004,45(6):1059-1064
Radioimmunotherapy (RIT) using (131)I-tositumomab has been used successfully to treat relapsed or refractory B-cell non-Hodgkin's lymphoma (NHL). Our approach to treatment planning has been to determine limits on radiation absorbed dose to critical nonhematopoietic organs. This study demonstrates the feasibility of using CT to adjust for actual organ volumes in calculating organ-specific absorbed dose estimates. METHODS: Records of 84 patients who underwent biodistribution studies after a trace-labeled infusion of (131)I-tositumomab for RIT (January 1990 and April 2003) were reviewed. Serial planar gamma-camera images and whole-body NaI probe counts were obtained to estimate (131)I-antibody source-organ residence times as recommended by the MIRD Committee. The source-organ residence times for standard man or woman were adjusted by the ratio of the MIRD phantom organ mass to the CT-derived organ mass. RESULTS: The mean radiation absorbed doses (in mGy/MBq) for our data using the MIRD model were lungs = 1.67; liver = 1.03; kidneys = 1.08; spleen = 2.67; and whole body = 0.3; and for CT volume-adjusted organ volumes (in mGy/MBq) were lungs = 1.30; liver = 0.92; kidneys = 0.76; spleen = 1.40; and whole body = 0.22. We determined the following correlation coefficients between the 2 methods for the various organs: lungs, 0.49 (P = 0.0001); liver, 0.64 (P = 0.004); kidneys, 0.45 (P = 0.0004); spleen, 0.22 (P = 0.0001); and whole body, 0.78 (P = 0.0001), for the residence times. For therapy, patients received mean (131)I administered activities of 19.2 GBq (520 mCi) after adjustment for CT-derived organ mass compared with 16.0 GBq (433 mCi) that would otherwise have been given had therapy been based only using standard MIRD organ volumes-a statistically significant difference (P = 0.0001). CONCLUSION: We observed large variations in organ masses among our patients. Our treatments were planned to deliver the maximally tolerated radiation dose to the dose-limiting normal organ. This work provides a simplified method for calculating patient-specific radiation doses by adjusting for the actual organ mass and shows the value of this approach in treatment planning for RIT. 相似文献
10.
Joseph G Rajendran Ajay K Gopal Darrel R Fisher Larry D Durack Ted A Gooley Oliver W Press 《Journal of nuclear medicine》2008,49(5):837-844
Myeloablative radioimmunotherapy using (131)I-tositumomab (anti-CD20) monoclonal antibodies is an effective therapy for B-cell non-Hodgkin's lymphoma. The amount of radioactivity for radioimmunotherapy may be determined by several methods, including those based on whole-body retention and on dose to a limiting normal organ. The goal of each approach is to deliver maximal myeloablative amounts of radioactivity within the tolerance of critical normal organs. METHODS: Records of 100 consecutive patients who underwent biodistribution and dosimetry evaluation after tracer infusion of (131)I-tositumomab before radioimmunotherapy were reviewed. We assessed organ and tissue activities over time by serial gamma-camera imaging to calculate radiation-absorbed doses. Organ volumes were determined from CT scans for organ-specific dosimetry. These dose estimates helped us to determine therapy on the basis of projected dose to the critical normal organ receiving a maximum tolerable radiation dose. We compared organ-specific dosimetry for treatment planning with the whole-body dose-assessment method by retrospectively analyzing the differences in projected organ-absorbed doses and their ratios. RESULTS: Mean organ doses per unit of administered activity (mGy/MBq) estimated by both methods were 0.33 for liver and 0.33 for lungs by the whole-body method and 1.52 for liver and 1.74 for lungs by the organ-specific method (P=0.0001). The median differences between methods were 0.92 mGy/MBq (range, 0.36-2.2 mGy/MBq) for lungs, 0.82 mGy/MBq (range, 0.28-1.67 mGy/MBq) for liver, and -0.01 mGy/MBq (range, -0.18-0.16 mGy/MBq) for whole body. The median ratios of the treatment activities based on limiting normal-organ dose were 5.12 (range, 2.33-10.01) for lungs, 4.14 (range, 2.16-6.67) for liver, and 0.94 (range, 0.79-1.22) for whole body. We found substantial differences between the dose estimated by the 2 methods for liver and lungs (P=0.0001). CONCLUSION: Dosimetry based on whole-body retention will underestimate the organ doses, and a preferable approach is to evaluate organ-specific doses by accounting for actual radionuclide biodistribution. Myeloablative treatments based on the latter approach allow administration of the maximum amount of radioactivity while minimizing toxicity. 相似文献