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Catharina M. L. Zegers Wouter van Elmpt Katrin Szardenings Hartmuth Kolb Alan Waxman Rathan M. Subramaniam Dae Hyuk Moon Jacqueline C. Brunetti Shyam M. Srinivas Philippe Lambin David Chien 《European journal of nuclear medicine and molecular imaging》2015,42(12):1840-1849
Purpose
Hypoxia is an important factor influencing tumor progression and treatment efficacy. The aim of this study was to investigate the repeatability of hypoxia PET imaging with [18F]HX4 in patients with head and neck and lung cancer.Methods
Nine patients with lung cancer and ten with head and neck cancer were included in the analysis (NCT01075399). Two sequential pretreatment [18F]HX4 PET/CT scans were acquired within 1 week. The maximal and mean standardized uptake values (SUVmax and SUVmean) were defined and the tumor-to-background ratios (TBR) were calculated. In addition, hypoxic volumes were determined as the volume of the tumor with a TBR >1.2 (HV1.2). Bland Altman analysis of the uptake parameters was performed and coefficients of repeatability were calculated. To evaluate the spatial repeatability of the uptake, the PET/CT images were registered and a voxel-wise comparison of the uptake was performed, providing a correlation coefficient.Results
All parameters of [18F]HX4 uptake were significantly correlated between scans: SUVmax (r?=?0.958, p?<?0.001), SUVmean (r?=?0.946, p?<?0.001), TBRmax (r?=?0.962, p?<?0.001) and HV1.2 (r?=?0.995, p?<?0.001). The relative coefficients of repeatability were 15 % (SUVmean), 17 % (SUVmax) and 17 % (TBRmax). Voxel-wise analysis of the spatial uptake pattern within the tumors provided an average correlation of 0.65?±?0.14.Conclusion
Repeated hypoxia PET scans with [18F]HX4 provide reproducible and spatially stable results in patients with head and neck cancer and patients with lung cancer. [18F]HX4 PET imaging can be used to assess the hypoxic status of tumors and has the potential to aid hypoxia-targeted treatments.63.
64.
Diagnostic value of biparametric magnetic resonance imaging (MRI) as an adjunct to prostate‐specific antigen (PSA)‐based detection of prostate cancer in men without prior biopsies 下载免费PDF全文
Soroush Rais‐Bahrami M. Minhaj Siddiqui Srinivas Vourganti Baris Turkbey Ardeshir R. Rastinehad Lambros Stamatakis Hong Truong Annerleim Walton‐Diaz Anthony N. Hoang Jeffrey W. Nix Maria J. Merino Bradford J. Wood Richard M. Simon Peter L. Choyke Peter A. Pinto 《BJU international》2015,115(3):381-388
65.
Ethnic variation in certain hematological and biochemical reference intervals in a south Indian healthy adult population 总被引:1,自引:0,他引:1
Sundaram M Mohanakrishnan J Murugavel KG Shankar EM Solomon S Srinivas CN Solomon SS Pulimi S Piwowar-Manning E Dawson S Livant E Kumarasamy N Balakrishnan P 《European Journal of Internal Medicine》2008,19(1):46-50
BACKGROUND: We established the biochemical and hematological reference intervals among a south Indian healthy adult population attending an HIV referral centre in Chennai, southern India. METHODS: In a cross sectional study, 213 study subjects (129 male and 84 female) were studied between March and August 2005. All of the parameters were analyzed using standard hematological and biochemical techniques. RESULTS: Certain biochemical (viz. total bilirubin, alanine transaminase, albumin, creatinine, total protein, lipid profile, creatine phosphokinase, uric acid and lactate) and hematological (mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration and lymphocyte levels) parameters presented higher upper limits. In addition, the upper limits of white blood cell count, platelet count, hematocrit, red blood cell count and hemoglobin level were low in comparison to the currently reported ranges. CONCLUSION: Ethnic variation in reference intervals was observed in certain biochemical and hematological analytes in a south Indian adult population. 相似文献
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Durga Praveen Meka Anne Kathrin Müller-Rischart Prakash Nidadavolu Behnam Mohammadi Elisa Motori Srinivas Kumar Ponna Helia Aboutalebi Mahmoud Bassal Anil Annamneedi Barbara Finckh Margit Miesbauer Natalie Rotermund Christian Lohr J?rg Tatzelt Konstanze F. Winklhofer Edgar R. Kramer 《The Journal of clinical investigation》2015,125(5):1873-1885
Parkin and the glial cell line–derived neurotrophic factor (GDNF) receptor RET have both been independently linked to the dopaminergic neuron degeneration that underlies Parkinson’s disease (PD). In the present study, we demonstrate that there is genetic crosstalk between parkin and the receptor tyrosine kinase RET in two different mouse models of PD. Mice lacking both parkin and RET exhibited accelerated dopaminergic cell and axonal loss compared with parkin-deficient animals, which showed none, and RET-deficient mice, in which we found moderate degeneration. Transgenic expression of parkin protected the dopaminergic systems of aged RET-deficient mice. Downregulation of either parkin or RET in neuronal cells impaired mitochondrial function and morphology. Parkin expression restored mitochondrial function in GDNF/RET-deficient cells, while GDNF stimulation rescued mitochondrial defects in parkin-deficient cells. In both cases, improved mitochondrial function was the result of activation of the prosurvival NF-κB pathway, which was mediated by RET through the phosphoinositide-3-kinase (PI3K) pathway. Taken together, these observations indicate that parkin and the RET signaling cascade converge to control mitochondrial integrity and thereby properly maintain substantia nigra pars compacta dopaminergic neurons and their innervation in the striatum. The demonstration of crosstalk between parkin and RET highlights the interplay in the protein network that is altered in PD and suggests potential therapeutic targets and strategies to treat PD. 相似文献
68.
Introduction
Every general dental practitioner and oral and maxillofacial surgeon needs a thorough knowledge of the diagnosis and management of medical emergencies. Cardiopulmonary arrest is the most urgent of emergencies and diagnosis must be done as soon as possible.Purpose
This paper discusses the importance of the International Liaison Committee on Resuscitation which forms the guidelines for cardiopulmonary resuscitation (CPR), highlighting the important changes in the guidelines of CPR from the year 2000 to 2010, the basic sequence of performing CPR and also the role of defibrillation and the use of automated external defibrillators. Finally the five part chain of survival which is of utmost importance to dental health care professionals and oral and maxillofacial surgeons.Conclusion
All dental health care personnel and oral & maxillofacial surgeons should recognize the importance of the changes in the guidelines of CPR, be trained and allowed to use a properly maintained defibrillator, to respond to cardiac arrest victims. 相似文献69.
70.
Alisha Gupta Sandeep Agarwala Nikhil Tandon M. Srinivas Minu Bajpai Devendra Kumar Gupta Arun Kumar Gupta Chandersekhar Bal Rakesh Kumar Veereshwar Bhatnagar 《Indian journal of pediatrics》2014,81(8):780-784