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1

The Human Aerodigestive Tract and Gastroesophageal Reflux  

Microsoft Academic Search

In order to appreciate fully the nature of supraesophageal complications of gastroesophageal reflux in humans, it is essential to view the problem within an evolutionary framework. Examination of the aerodigestive tract anatomy of our mammalian relatives shows that this region in humans is highly derived as compared to other mammals. Among the specializations that adult humans exhibit is a caudal

Jeffrey T Laitman; Joy S Reidenberg

1997-01-01

2

Toxicology of upper aerodigestive tract pollutants  

SciTech Connect

The field of environmental toxicology has become quite important to the study of environmental health in human beings. The stability of the ecosystem in which we live is threatened by the nearly 5 million chemical compounds that have been synthesized worldwide, many of which have real or potentially toxic effects on the environment and on life forms. Four major groups of chemicals--metallic elements, nonmetallic elements, organic compounds and inorganic compounds--have certain agents within them that are known toxins to human beings. Some of these agents have an as yet unknown effect, whereas others have been well characterized. They can be found in the workplace, home, and outdoors, and many are unseen and odorless. In the past, most agents have been described in terms of their carcinogenic potential or major toxic effects on organ systems. It is now likely that the important characterization of some of these agents referrable to the upper aerodigestive tract should be at their receptor sites and identify the very discrete and small effects on these sites and their cumulative effects. The concept of threshold is probably an arbitrary one because to date these discrete effects have not been studied. Susceptibility on an individual basis probably varies from low to high, depending on the patient's immunologic and defense mechanisms and the existence of congenital or acquired risk factors. New attention must be given to more subtle effects on the upper aerodigestive tract (i.e., sinusitis and laryngitis) in view of the potential effects of certain toxic agents on these tissues.

Holt, G.R. (Department of Otolaryngology--Head and Neck Surgery, University of Texas Health Science Center, San Antonio (United States))

1992-06-01

3

[Recurrence of upper aerodigestive tract tumors].  

PubMed

Recurrences of tumours of the upper aerodigestive tract are frequent despite the improvement of the primary treatment and they limit the rate of survival long-term. They occur in patients with multiple co-morbidities, often associated with sequelae or side effects of earlier treatments. The salvage treatment will add a cumulative toxicity and therapeutic options are limited. The choice will go from curator to palliative treatment. The report benefit-risk must be assessed in each case depending on the terrain and prognostic factors that have been identified, such as performance status, the time between initial disease and the recurrence, the site and the stratification of the recurrence. In operable non-metastatic recurrence surgery remains the treatment of choice. Multimodal treatment involving surgery, radiation therapy and chemotherapy in this context is being evaluated. Non-operable tumors have long been considered only in a palliative context. The evaluation of detailed irradiation as bifractionnated radiotherapy combined with chemotherapy helped establish protocols allowing long-term survivals and consider these treatments as potentially curators. However, the toxicity of these treatments is important. That is why the technical innovations of the radiation and the development of new chemotherapeutic agents today offer opportunities remaining to assess. The use of irradiation targeted by intensity-modulated radiation therapy (IMRT), and stereotactic radiotherapy by decreasing the irradiated volume should decrease the toxicity. Generally better tolerated than conventional chemotherapy agents, targeted therapies also took their places associated with radiotherapy in the treatment of these patients already treated. Cetuximab was the first agent obtaining an indication. Other agents are being evaluated in metastatic recurrent tumors, including exploring the possibilities of radiopotentialisation nanoparticles and the inhibitors of apoptosis proteins. PMID:24886903

Martin, Laurent; Zoubir, Mustapha; Le Tourneau, Christophe

2014-05-01

4

Foreign bodies in the aerodigestive tract in pediatric patients  

Microsoft Academic Search

Objective: To investigate pediatric foreign body cases in the aerodigestive tract, and to elucidate the characteristic problems in Japan. Methods: A total of 310 pediatric patients (age 15 or below), gathered from two medical university hospitals (University of Tokyo and Jichi Medical School), were included in this study. Data were collected by retrospective chart review and were statistically analyzed. Results:

Ryuzaburo Higo; Yu Matsumoto; Keiichi Ichimura; Kimitaka Kaga

2003-01-01

5

Concordance of Two Endoscopic Procedures for Diagnosis of Carcinoma of the Upper Aerodigestive Tract  

ClinicalTrials.gov

Upper Aerodigestive Tract Lesions; Neoplasms, Oropharyngeal; Oropharyngeal Cancer; Neoplasms, Hypopharyngeal; Hypopharyngeal Cancer; Head and Neck Neoplasms; UADT Neoplasms; Carcinoma, Squamous Cell; Papilloma

2013-09-23

6

Feasibility of volume-of-interest (VOI) scanning technique in cone beam breast CT - a preliminary study  

SciTech Connect

This work is to demonstrate that high quality cone beam CT images can be generated for a volume of interest (VOI) and to investigate the exposure reduction effect, dose saving, and scatter reduction with the VOI scanning technique. The VOI scanning technique involves inserting a filtering mask between the x-ray source and the breast during image acquisition. The mask has an opening to allow full x-ray exposure to be delivered to a preselected VOI and a lower, filtered exposure to the region outside the VOI. To investigate the effects of increased noise due to reduced exposure outside the VOI on the reconstructed VOI image, we directly extracted the projection data inside the VOI from the full-field projection data and added additional data to the projection outside the VOI to simulate the relative noise increase due to reduced exposure. The nonuniform reference images were simulated in an identical manner to normalize the projection images and measure the x-ray attenuation factor for the object. Regular Feldkamp-Davis-Kress filtered backprojection algorithm was used to reconstruct the 3D images. The noise level inside the VOI was evaluated and compared with that of the full-field higher exposure image. Calcifications phantom and low contrast phantom were imaged. Dose reduction was investigated by estimating the dose distribution in a cylindrical water phantom using Monte Carlo simulation based Geant4 package. Scatter reduction at the detector input was also studied. Our results show that with the exposure level reduced by the VOI mask, the dose levels were significantly reduced both inside and outside the VOI without compromising the accuracy of image reconstruction, allowing for the VOI to be imaged with more clarity and helping to reduce the breast dose. The contrast-to-noise ratio inside the VOI was improved. The VOI images were not adversely affected by noisier projection data outside the VOI. Scatter intensities at the detector input were also shown to decrease significantly both inside and outside the VOI in the projection images, indicating potential improvement of image quality inside the VOI and contribution to dose reduction both inside and outside the VOI.

Chen Lingyun; Shaw, Chris C.; Altunbas, Mustafa C.; Lai, C.-J.; Liu Xinming; Han Tao; Wang Tianpeng; Yang, Wei T.; Whitman, Gary J. [Department of Imaging Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030-4009 (United States); Department of Diagnostic Radiology, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030-4009 (United States)

2008-08-15

7

Alcohol and tobacco misuse: Reducing aerodigestive cancer risk  

PubMed Central

Significant concerns over the health, social and economic burdens of the two most common, and frequently co-misused drugs of abuse, alcohol and tobacco, has encouraged focused but separate health promotion and disease prevention policies. However, this separation of focus means that while individuals who present with alcohol-related problems are increasingly supported to attain and maintain abstinence from alcohol they are not routinely assisted to refrain from smoking. This is tragically inopportune as alcohol and tobacco have an established “synergistic” effect on aerodigestive cancer risk. Moreover, even when patients successfully tackle their alcohol problems they remain at increased risk for developing these cancers, especially if they continue to smoke. A case series is presented together with a discussion on how service provision for co-misuse could be improved to obviate aerodigestive cancer risk. Given the prevalence of alcohol and tobacco use in the United Kingdom, these observations may have far reaching implications for the individual, health provider(s) and wider society.

Wright, Gavin; Morgan, Marsha Y

2013-01-01

8

Pediatric upper aero-digestive and respiratory tract burns  

PubMed Central

Upper aero-digestive and respiratory tract burns may occur in isolation or in association with cutaneous burn injury. Major respiratory burns have been linked with a high mortality and morbidity. Despite the importance of these injuries there have been few studies in children. A retrospective case note review between December 2000 and March 2011 of all pediatric upper aero-digestive and respiratory tract burns referred to the New South Wales Statewide Burn Injury Service was performed. Data were collected on patient characteristics, injury details, requirement for intubation, length of stay (LOS), morbidity and mortality. There were 33 patients diagnosed, with a median age of 5.4 years and a male to female ratio of 1.2:1. Mechanism of injury was ingestion of a caustic material (n=15), flame (n=11) or scald (n=7). Overall 14 (42%) patients were intubated; the majority associated with burns to the face (79%) and oropharynx (64%). Median LOS was 6 days (range 3 to 23). Of those patients admitted to intensive care, 50% had a positive bacterial culture. The most common sites of infection were tracheal/endotracheal (80%) and burn sites (44%). There were 2 (6%) deaths in the series. Whilst the majority of children with upper airway and respiratory tract burns required intubation, the overall morbidity and mortality was low compared to adult series. This may reflect that a number of children suffered an upper aero digestive tract burn following ingestion of a caustic material or hot liquids, rather than a lower tract, inhalational flame burn.

Ofri, Adam; Harvey, John G; Holland, Andrew J A

2013-01-01

9

Low dose, low noise, and high resolution volume of interest (VOI) imaging in C-arm flat-detector CT  

NASA Astrophysics Data System (ADS)

The high flexibility of C-arm flat-detector computed tomography (FDCT) is used in a volume of interest (VOI) imaging method to handle the challenges of increasing spatial resolution, reducing noise and saving dose. A low-dose overview scan of the object and a high-dose scan of an arbitrary VOI are combined. The first scan is adequate for orientation to select the VOI and the second scan assures high image quality in the VOI. The combination is based on a forward projection of the reconstructed overview volume and the measured VOI data in the raw data domain. Differences in the projection values are matched before a standard Feldkamp-type reconstruction is performed. In simulations, spatial resolution, noise and contrast detectability were evaluated. Measurements of an anthropomorphic phantom were used to validate the proposed method for realistic application. In Monte Carlo dose simulations the dose reduction potential was investigated. By combination of the two scans an image is generated which covers the whole object and provides the actual VOI at high image quality. Spatial resolution was increased whereas noise was decreased from outside to inside the VOI, e.g. for the simulations from 0.8 lp/mm to 3.0 lp/mm and from 39 HU to 18 HU, respectively. Simultaneously, the cumulative dose for this two-scan procedure was significantly reduced in comparison to a conventional high dose scan, e.g. for the performed simulations and measurements by about 95 %. The proposed VOI approach offers significant benefits with respect to high-resolution and low-contrast imaging of a VOI at reduced dose.

Kolditz, Daniel; Kyriakou, Yiannis; Kalender, Willi A.

2010-03-01

10

Feldkamp-type VOI reconstruction from super-short-scan cone-beam data.  

PubMed

Based on the fan-beam reconstruction formula recently developed by Noo et al. [Phys. Med. Biol. 47, 2525-2546 (2002)] we develop a Feldkamp-type algorithm for the reconstruction of a volume of interest (VOI) from super-short-scan data. With either a circular or spiral scanning locus in our VOI reconstruction scheme, we first estimate fan-beam data from cone-beam data using the popular "cosine correction" scheme, and perform reconstruction based on Noo's FBP-type fan-beam reconstruction. Our proposed algorithm is tested using the three-dimensional (3-D) Shepp-Logan phantom. The experimental results show that the new algorithm can be applied to multi-source 4-D CT with significantly superior temporal resolution and temporal consistency relative to the Katsevich algorithm, which is the state of the art for exact helical cone-beam reconstruction. PMID:15259639

Yu, Hengyong; Wang, Ge

2004-06-01

11

Palliation of malignant aerodigestive fistulae with self-expanding metallic stents.  

PubMed

Malignant aerodigestive fistulae are rare but devastating sequelae of thoracic cancers, most commonly associated with esophageal cancer. Survival following development of a malignant aerodigestive fistula is measured in weeks. Palliation is the primary goal of therapy and to this end, we report the use of self-expanding metallic stents (SEMS) as treatment. Between May 1999 and January 2004, 12 patients were treated for malignant aerodigestive fistulae. The underlying diagnosis was esophageal cancer for 10 patients, and non-small cell lung cancer for two others. All patients were symptomatic and fistulae were diagnosed by esophagoscopy in seven, bronchoscopy in two, and esophagram in three. Seven covered Wallstents (seven esophageal) and eight covered Ultraflex (five tracheal and three esophageal) were used. A single stent was placed in eight patients (seven esophageal and one tracheal). Three patients required esophageal and tracheal stents and one patient needed two tracheal stents. General anesthesia was required in 50% of the patients. There were no procedure-related complications. Symptoms were palliated in 100% of patients and oral intake was reinstituted in 42% (5/12). All the patients were discharged from hospital after SEMS placement and one patient returned for an uneventful tracheal stent replacement secondary to mucus impaction 2 months later. SEMS placement is an effective strategy to palliate malignant aerodigestive fistulae. Complications are rare and symptoms are alleviated in most patients. PMID:17760651

Murthy, S; Gonzalez-Stawinski, G V; Rozas, M S; Gildea, T R; Dumot, J A

2007-01-01

12

Chromosome Sensitivity to Bleomycin-induced Mutagenesis, an Independent Risk Factor for Upper Aerodigestive Tract Cancers  

Microsoft Academic Search

Defective DNA repair capability, measured by enumerating mutagen- induced chromosomal lesions, might explain variable host susceptibility to the action of environmental carcinogens. We compared sensitivity to bleomycin-induced chromosome damage in 75 patients (53 men and 22 women)with previously untreated upper aerodigestive tract malignancies with that in 62 healthy control subjects. Data on tobacco and alcohol use were derived from a

Margaret R. Spitz; John J. Fueger; Nancy A. Beddingfield; John F. Annegers; T. C. Hsu; Guy R. Newell; Stimson P. Schantz

13

Les kystes hydatiques du foie rompus dans les voies biliaires: ? propos de 120 cas  

PubMed Central

Etude rétrospective rapportant une série de kystes hydatiques rompus dans les voies biliaires colligés dans le service de chirurgie de l'hôpital militaire Avicenne à Marrakech. Entre 1990 à 2008, sur 536 kystes hydatiques du foie opérés dans le service, 120 étaient compliqués de rupture dans les voies biliaires soit 22,38%. Il y avait 82hommes et 38 femmes. L’âge moyen était de 35 ans avec des extrêmes allant de 10 à 60 ans. La clinique était dominée par la crise d'angiocholite ou une douleur du flanc droit. L'ictère était isolé dans huit cas. La fistule biliokystique était latente dans plus de 50% des cas. Le traitement a consisté en une résection du dôme saillant dans103cas (85,84%), une périkystectomie chez 11 malades (9,16%) et une lobectomie gauche dans six cas (5%). Le traitement de la fistule bilio kystique a consisté en une suture chez 36malades et un drainage bipolaire dans 25 cas, La déconnexion kysto-biliaire ou cholédocotomie trans hépatico kystique selon Perdomo était pratiquée dans 49cas et une anastomose bilio-digestive cholédoco-duodénale dans 10 cas. La durée moyenne d'hospitalisation était de 20jours. Nous déplorons deux décès par choc septique et un troisième par encéphalopathie secondaire à une cirrhose biliaire. La morbidité était représentée par huit abcès sous phrénique, douze fistules biliaires prolongées et deux occlusions intestinales. Les kystes hydatiques rompus dans les voies biliaires représentent la complication la plus grave de cette pathologie bénigne. Le traitement repose sur des méthodes radicales qui sont d'une efficacité reconnue, mais de réalisation dangereuse et les méthodes conservatrices, en particulier la déconnexion kysto-biliaire qui est une méthode simple et qui donne de bons résultats à court et à long terme.

Moujahid, Mountassir; Tajdine, Mohamed Tarik

2011-01-01

14

Life course social mobility and risk of upper aerodigestive tract cancer in men  

Microsoft Academic Search

The aim of this study was to explore associations between social mobility and tumours of the upper aero-digestive tract (UADT),\\u000a focussing on life-course transitions in social prestige (SP) based on occupational history. 1,796 cases diagnosed between\\u000a 1993 and 2005 in ten European countries were compared with 1585 controls. SP was classified by the Standard International\\u000a Occupational Prestige Scale (SIOPS) based

N. Schmeisser; D. I. Conway; P. A. McKinney; A. D. McMahon; H. Pohlabeln; M. Marron; S. Benhamou; C. Bouchardy; G. J. Macfarlane; T. V. Macfarlane; P. Lagiou; A. Lagiou; V. Bencko; I. Holcátová; F. Merletti; L. Richiardi; K. Kjaerheim; A. Agudo; R. Talamini; J. Polesel; C. Canova; L. Simonato; R. Lowry; A. Znaor; C. Healy; B. E. McCarten; M. Hashibe; P. Brennan; W. Ahrens

2010-01-01

15

Penicillamine as a Potent Protector against Injurious Effects of Cigarette Smoke in Aerodigestive Tract Cancer  

Microsoft Academic Search

Background: Cigarette smoke (CS) is the major risk factor for aerodigestive tract cancers such as lung and oral cancers. Methods: In in vitro models of lung and oral cancers, we found D-penicillamine (PenA) to be a most potent protector against CS, both in the absence and presence of saliva (a highly pro-oxidative condition). Results: The survival rate of lung cancer

Rafael Nagler; Shiri Cohen; Dana Savulescu; Svetlana Leschiner; Irina Otradnov; Moshe Gavish

2010-01-01

16

Metastatic melanoma to the upper aerodigestive tract: a systematic review of the literature.  

PubMed

This study is a systematic review of the literature that was performed to clarify the natural history and treatment outcomes of upper aerodigestive tract metastases from cutaneous melanoma. A search of the MEDLINE database was undertaken from 1950 to 2013 to identify relevant manuscripts for this review. Article inclusion required cases with documentation of previous cutaneous melanoma primary lesions, adequate survival data, and description of metastatic treatment. Individual patient data were extracted from source articles for analysis of survival outcomes. A systematic search revealed 34 relevant articles with 37 cases for inclusion. Metastases were identified throughout the upper aerodigestive tract with a predilection for the oropharynx, larynx, and oral cavity. Treatment outcomes were estimated with the Kaplan-Meier method, with survival of 37% and 16% at 1 and 5 years, respectively. As expected from previous reports, 73% presented with disseminated disease burden with almost universally poor prognosis despite locoregional or systemic therapy. Conversely, a group of patients with limited metastatic burden had improved treatment response with a 1-year survival of 90%, denoting a hazard ratio of 9.7332 (95% confidence interval, 4.5-21.1) for disseminated disease in comparison. Upper aerodigestive tract metastases of melanoma thus are rare clinical entities that in general present in the setting of disseminated disease and evidently necessitate a focus on palliation. In contrast, for those with a limited metastatic burden, aggressive multimodality therapy including complete metastectomy can produce a significant survival advantage. PMID:24115042

Mifsud, Matthew; Padhya, Tapan A

2014-05-01

17

Unique Features of Obstructive Sleep Apnea in World Trade Center Responders With Aerodigestive Disorders  

PubMed Central

Objectives To compare obstructive sleep apnea (OSA) in World Trade Center (WTC) responders with aerodigestive disorders and snoring with non-WTC habitual snorers, and to distinguish features of OSA in a subset of responders with worsening of snoring after 9/11 from responders with previous habitual snoring. Methods Cross-sectional comparative study of 50 WTC Medical Monitoring and Treatment Program responders with aerodigestive disorders and snoring and 50 nonresponders with snoring. Responders with worsening of snoring after 9/11 were compared with previous habitual snorers. Results While there was a strong correlation between body mass index (BMI), weight, and Apnea + Hypopnea Index (r = 0.36, P = 0.001; r = 0.29, P = 0.044) in the nonresponders, no correlation between either BMI or weight and Apnea + Hypopnea Index was found in the responders. Responders with worsening of snoring after 9/11 had a significantly lower BMI than previous habitual snorers. Conclusion Mechanisms other than obesity are important in the pathogenesis of OSA in WTC responders with aerodigestive disorders.

Sunderram, Jag; Udasin, Iris; Kelly-McNeil, Kathie; Ko, Susan; Cepeda, Clarimel; Marroccoli, Barbara; Perret, Carol; Ohman-Strickland, Pamela; Scardella, Anthony; Kipen, Howard

2014-01-01

18

Investigation on PI-line selecting method base on GPU accelerated back-projection filtered VOI reconstruction  

NASA Astrophysics Data System (ADS)

Reconstruction algorithms based on PI-line or Chord are active subject in CBCT. Among them back-projection filtered (BPF) reconstruction algorithm has obvious influence for its exact reconstruction results and less computations especially in selected volume of interesting (VOI) regions. However, the selecting and sampling method of PI-line segment can directly affect the quality of reconstructed images. In this paper, we proposed a general PI-line selecting scheme to reconstruct VOI regions by using BPF algorithm, which mainly based on the relationship between reconstructed coordinate and PI-line coordinate. The proposed scheme is applicable for GPU accelerated back-projection filtered reconstruction.

Zheng, Han; Yu, Yanyan; Kang, Yan; Liu, Jiren

2010-03-01

19

Aerodigestive Foreign Bodies in Adult Ethiopian Patients: A Prospective Study at Tikur Anbessa Hospital, Ethiopia  

PubMed Central

Introduction. Foreign bodies (FBs) in the aerodigestive tract are important causes of morbidity and mortality and pose diagnostic and therapeutic challenges. The best method of removal of an esophageal and tracheobronchial FB is endoscopic guided extraction. Objective. To present our experience of the removal of aerodigestive FBs in adult Ethiopian patients using rigid endoscopes. Methods. A hospital-based prospective study, at Tikur Anbessa Referral and Teaching Hospital, from January 2011 to December 2012 (over two years). Results. A total of 32 patients (18 males and 14 females) with a mean age of 28.0 ± 12.74 years were treated for FB ingestion and aspiration at Tikur Anbessa Hospital. The FBs were impacted at the esophagus in 18 (56.2%) patients, at the pharynx in 7 (21.8%), and at the air way in 7 (21.8%) patients. Pieces of bones were the commonest objects found in the esophagus (17/18 of the cases) and the pharynx (4/7), while fractured tracheostomy tubes and needles were frequently seen in the air way (3/7 cases each). The foreign bodies were visible in plain radiographs of 26 (81.2%) patients. Successful extraction of FBs was achieved by using Mc gill forceps in 11 cases, rigid esophagoscopes in 9 patients, and bronchoscopes in 4 cases. Four cases required open surgery to remove the foreign bodies. Two complications (one pneumothorax and one esophageal perforation) occurred. All patients were discharged cured. Discussion and Recommendations. Aerodigestive FBs are not so rare in the hospital and timely diagnosis and removal of accidentally ingested and aspirated foreign body should be performed so as to avoid the potentially lethal complications associated. Rigid esophagoscopy requires general anesthesia and is associated with its own complications, but our experience and outcome of its use are encouraging.

Bekele, Abebe

2014-01-01

20

Esophageal sensation in premature human neonates: temporal relationships and implications of aerodigestive reflexes and electrocortical arousals  

PubMed Central

Electrocortical arousal (ECA) as an effect of visceral provocation or of its temporal relationships with aerodigestive reflexes in premature neonates is not known. We tested the hypothesis that esophageal provocation results in both esophageal reflex responses and ECAs during sleep and that ECAs are dependent on the frequency characteristics of esophageal neuromotor responses. We defined the spatiotemporal relationship of ECAs in relation to 1) spontaneous pharyngoesophageal swallow sequences and gastroesophageal reflux (GER) events and 2) sensory-motor characteristics of esophageal reflexes. Sixteen healthy premature neonates born at 27.9 ± 3.4 wk were tested at 36.8 ± 1.9 wk postmenstrual age. Ninety-five midesophageal and 31 sham stimuli were given in sleep during concurrent manometry and videopolysomnography. With stimulus onset as reference point, we scored the response latency, frequency occurrence and duration of arousals, peristaltic reflex, and upper esophageal sphincter contractile reflex (UESCR). Changes in polysomnography-respiratory patterns and esophageal sensory-motor parameters were scored by blinded observers. Significantly (for each characteristic listed, P < 0.05), swallow sequences were associated with arousals and sleep state changes, and arousals were associated with incomplete peristalsis, response delays to lower esophageal sphincter relaxation, and prolonged esophageal clearance. GER events (73.5%) provoked arousals, and arousals were associated with response delays to peristaltic reflexes or clearance, sleep state modification, and prolonged respiratory arousal. Midesophageal stimuli (54%) provoked arousals and were associated with increased frequency, prolonged latency, prolonged response duration of peristaltic reflexes and UESCR, and increased frequency of sleep state changes and respiratory arousals. In human neonates, ECAs are provoked upon esophageal stimulation; the sensory-motor characteristics of esophageal reflexes are distinct when accompanied by arousals. Aerodigestive homeostasis is defended by multiple tiers of aerodigestive safety mechanisms, and when esophageal reflexes are delayed, cortical hypervigilance (ECAs) occurs.

Parks, Vanessa N.; Peng, Juan; Dzodzomenyo, Samuel; Fernandez, Soledad; Shaker, Reza; Splaingard, Mark

2012-01-01

21

Esophageal sensation in premature human neonates: temporal relationships and implications of aerodigestive reflexes and electrocortical arousals.  

PubMed

Electrocortical arousal (ECA) as an effect of visceral provocation or of its temporal relationships with aerodigestive reflexes in premature neonates is not known. We tested the hypothesis that esophageal provocation results in both esophageal reflex responses and ECAs during sleep and that ECAs are dependent on the frequency characteristics of esophageal neuromotor responses. We defined the spatiotemporal relationship of ECAs in relation to 1) spontaneous pharyngoesophageal swallow sequences and gastroesophageal reflux (GER) events and 2) sensory-motor characteristics of esophageal reflexes. Sixteen healthy premature neonates born at 27.9 ± 3.4 wk were tested at 36.8 ± 1.9 wk postmenstrual age. Ninety-five midesophageal and 31 sham stimuli were given in sleep during concurrent manometry and videopolysomnography. With stimulus onset as reference point, we scored the response latency, frequency occurrence and duration of arousals, peristaltic reflex, and upper esophageal sphincter contractile reflex (UESCR). Changes in polysomnography-respiratory patterns and esophageal sensory-motor parameters were scored by blinded observers. Significantly (for each characteristic listed, P < 0.05), swallow sequences were associated with arousals and sleep state changes, and arousals were associated with incomplete peristalsis, response delays to lower esophageal sphincter relaxation, and prolonged esophageal clearance. GER events (73.5%) provoked arousals, and arousals were associated with response delays to peristaltic reflexes or clearance, sleep state modification, and prolonged respiratory arousal. Midesophageal stimuli (54%) provoked arousals and were associated with increased frequency, prolonged latency, prolonged response duration of peristaltic reflexes and UESCR, and increased frequency of sleep state changes and respiratory arousals. In human neonates, ECAs are provoked upon esophageal stimulation; the sensory-motor characteristics of esophageal reflexes are distinct when accompanied by arousals. Aerodigestive homeostasis is defended by multiple tiers of aerodigestive safety mechanisms, and when esophageal reflexes are delayed, cortical hypervigilance (ECAs) occurs. PMID:21852361

Jadcherla, Sudarshan R; Parks, Vanessa N; Peng, Juan; Dzodzomenyo, Samuel; Fernandez, Soledad; Shaker, Reza; Splaingard, Mark

2012-01-01

22

Incidence of foreign bodies in aerodigestive tract in vindhya region: our experience.  

PubMed

Foreign bodies in aerodigestive tract are frequent occurrence and may lead to life threatening situation due to obstruction caused in respiratory passages. To present foreign body ingestion cases observed in a 5-year period at the S.S. Medical College and G.M. Hospital, Rewa (MP). The present study is a retrospective analysis including 108 patients of foreign bodies of aerodigestive tract of Vindhya region who presented to the S.S. Medical College and G.M. Hospital, Rewa from January 2008 to August 2012. About 92 patients of total 108 patients had evidence of foreign body in food passage with age ranging from 9 month to 85 years. Most patients 65 (70.65 %) belong to <10 year age group. Radiological evidence was found in 76 (82.6 %) patients. Most common foreign body was found to be coin 75 (81.52 %). The commonest site of lodgement was cricopharynx. About 16 patients of total 108 patients had evidence of foreign body in airway with age ranging from 9 months to 72 years. Most cases 8 (50 %) belong to <10 year age. Maximum cases showed vegetative foreign body with right bronchus (58.33 %) as commonest site of lodgement. Early detection by meticulous history, imaging modality and prompt management remains basis for favourable outcome and prevents future complications. PMID:24822150

Gupta, Richa; Poorey, V K

2014-06-01

23

Investigation on PI-line selecting method base on GPU accelerated back-projection filtered VOI reconstruction  

Microsoft Academic Search

Reconstruction algorithms based on PI-line or Chord are active subject in CBCT. Among them back-projection filtered (BPF) reconstruction algorithm has obvious influence for its exact reconstruction results and less computations especially in selected volume of interesting (VOI) regions. However, the selecting and sampling method of PI-line segment can directly affect the quality of reconstructed images. In this paper, we proposed

Han Zheng; Yanyan Yu; Yan Kang; Jiren Liu

2010-01-01

24

Protective Role of Aerodigestive Reflexes Against Aspiration: Study on Subjects With Impaired and Preserved Reflexes  

PubMed Central

BACKGROUND & AIMS Direct evidence to support the airway protective function of aerodigestive reflexes triggered by pharyngeal stimulation was previously demonstrated by abolishing these reflexes by topical pharyngeal anesthesia in normal subjects. Studies have also shown that these reflexes deteriorate in cigarette smokers. Aim of this study was to determine the influence of defective pharyngeal aerodigestive reflexes on airway protection in cigarette smokers. METHODS Pharyngoglottal Closure reflex; PGCR, Pharyngo-UES Contractile reflex; PUCR, and Reflexive Pharyngeal Swallow; RPS were studied in 15 healthy non-smokers (24.2 ± 3.3 SD y, 7 males) and 15 healthy chronic smokers (27.3 ± 8.1, 7 males). To elicit these reflexes and to evaluate aspiration, colored water was perfused into the hypopharynx at the rate of 1 mL/min. Maximum volume of water that can safely dwell in the hypopharynx before spilling into the larynx (Hypopharyngeal Safe Volume; HPSV) and the threshold volume to elicit PGCR, PUCR, and RPS were determined in smokers and results compared with non-smokers. RESULTS At baseline, RPS was elicited in all non-smokers (100%) and in only 3 of 15 smokers (20%; P < .001). None of the non-smokers showed evidence of laryngeal spillage of water, whereas 12 of 15 smokers with absent RPS had laryngeal spillage. Pharyngeal anesthesia abolished RPS reflex in all non-smokers resulting in laryngeal spillage. The HPSV was 0.61 ± 0.06 mL and 0.76 ± 0.06 mL in non-smokers and smokers respectively (P = .1). CONCLUSIONS Deteriorated reflexive pharyngeal swallow in chronic cigarette smokers predispose them to risks of aspiration and similarly, abolishing this reflex in non-smokers also results in laryngeal spillage. These observations directly demonstrate the airway protective function of RPS.

DUA, KULWINDER; SURAPANENI, SRI NAVEEN; KURIBAYASHI, SHIKO; HAFEEZULLAH, MOHAMMED; SHAKER, REZA

2012-01-01

25

40Ar/39Ar laserprobe study of the Day Nui Con Voi Metamorphic Complex, Vietnam  

NASA Astrophysics Data System (ADS)

The garnet bearing gneiss within the Day Nui Con Voi (DNCV) Metamorphic Complex along the Red River Shear Zone (RRSZ) in North Vietnam, recorded a long tectonothermal history since the Indosinian orogeny. In-situ 40Ar/39Ar laserprobe study of biotite inclusions within garnet porphyroblasts and matrix biotites, combining with microstructural and scanning electron microscopy (SEM) studies, deciphered the timing and duration of thermal events. Biotites from two matrix fabrics from different deformation events show approximately similar 40Ar/39Ar age ranges in 19-24Ma, depending grain size. These matrix biotite ages are best interpreted to record a rapid cooling event associating with the left-lateral shearing event of the RRSZ. Whereas, all biotite inclusions exhibit age zoning patterns with 40Ar/39Ar ages gradually increase from 17 Ma to more than 28 Ma according to their diffusion pathways. These age variations may have resultant from a combination effect of argon retention by garnet shielding, which provides a best recorder to the metamorphic event, and argon diffusion loss along the deformed cracks during the shearing event of the RRSZ. Diffusion modeling of these age zoning indicated that the total duration of argon diffusion loss may have lasted for nearly 9 Myr and argon diffusion may have occurred sometime around 24.5Ma. These results are generally in good agreement with previous interpretation, but provide better resolution of 40Ar/39Ar age data for deciphering the history of thermal event in the DNCV Metamorphic Complex and the left-lateral shearing event of the RRSZ in Vietnam, as well.

Wu, C.; Lo, C.; Yeh, M.; Chung, S.; Lee, T.

2009-12-01

26

Deformation sequences of the Day Nui Con Voi metamorphic belt, northern Vietnam  

NASA Astrophysics Data System (ADS)

The correlation of structure, microstructure and metamorphic assemblages is of fundamental importance to the understanding of the complex tectonic history and kinematics of the Day Nui Con Voi (DNCV) metamorphic belt in Vietnam along the Ailao Shan-Red River (ASRR) shear zone as it provides constraints on the relative timing of the deformation, kinematics and metamorphism. High-grade metamorphic rocks of amphibolite faces showed consistent deformation sequences of three folding events followed by one brittle deformation through all four cross sections from Lao Cai to Viet Tri indicated the DNCV belt experienced similar deformation condition throughout its length. The first deformation event, D1, produced up-right folds (locally preserved) with sub-vertical, NE-SW striking axial planes with dextral sense of shear probably formed during the early phase of the lowermost Triassic Indosinian orogeny. Followed by this compressional event is a gravitational collapsing event, D2, which is the major deformation and metamorphic event characterized by kyanite grade metamorphism and large scale horizontal folds with NW-SE (320) striking sub-horizontal axial pane showing sinsistral sense of shear most likely formed during the Oligocene-Miocene SE extrusion of Indochina peninsula. The 3rd folding event, D3, is a post-metamorphism doming event with NW-SE (310) striking sub-vertical axial plane that folded/tilted the once sub-horizontal D2 axial planes into shallowly (<30 degrees) NE dipping on the NE limb, and SW dipping on the SW limb possibly due to left-lateral movement of the N-S trending Xian Shui He fault system in Mid-Miocene. The outward decreasing of the metamorphic grade from kyanite to garnet then biotite indicated the D3 occurred post metamorphism. Reactivation of the sub-horizontal D2 fold axial planes showed dextral sense of shear possibly due to Late Miocene-Pliocene right-lateral movement of the ASRR shear zone. This right lateral movement continuously deformed the DNCV with brittle fractures such as joints and normal faults (D4) striking NE-SW to E-W and NW-SE.

Yeh, M. W.; Lee, T. Y.; Lo, C. H.; Chung, S. L.; Lan, C. Y.; Lee, J. C.; Lin, T. S.; Lin, Y. J.

2003-04-01

27

P- T- t paths and post-metamorphic exhumation of the Day Nui Con Voi shear zone in Vietnam  

NASA Astrophysics Data System (ADS)

The Day Nui Con Voi belt in Vietnam is the southeasternmost part of the Red River shear zone in Asia. It is a narrow high-grade metamorphic core complex consisting of garnet-sillimanite-biotite gneisses, mylonite bands, amphibolite layers and migmatites. Geothermobarometric study of the complex revealed that the peak metamorphism took place under amphibolite-facies conditions of 690 -60 +30°C and 0.65±0.15 GPa and the subsequent mylonitization occurred under greenschist-facies conditions of ˜480°C and under 0.3 GPa. Fifteen synkinematic hornblende and biotite separates from gneisses, amphibolites and mylonites were dated with the K/Ar method. Hornblende separates from the Day Nui Con Voi give K-Ar ages of 26.4-28.5 Ma, and the biotite separates do give 24.5-24.7 Ma. Combination of thermobarometric and geochronological data yields the cooling history of 500°C at 28 Ma and 300°C at 24 Ma with a cooling rate of 70-110°C Ma -1, and 23 km post-metamorphic exhumation of the core complex. The first 16 km exhumation from the peak of metamorphism (at probably 31 Ma) to 28 Ma was triggered by the left-lateral strike-slip displacement of the Red River shear zone.

Nam, Tran Ngoc; Toriumi, Mitsuhiro; Itaya, Tetsumaru

1998-05-01

28

Life course social mobility and risk of upper aerodigestive tract cancer in men.  

PubMed

The aim of this study was to explore associations between social mobility and tumours of the upper aero-digestive tract (UADT), focussing on life-course transitions in social prestige (SP) based on occupational history. 1,796 cases diagnosed between 1993 and 2005 in ten European countries were compared with 1585 controls. SP was classified by the Standard International Occupational Prestige Scale (SIOPS) based on job histories. SIOPS was categorised in high (H), medium (M) and low (L). Time weighted average achieved and transitions between SP with nine trajectories: H --> H, H --> M, H --> L, M --> H, M --> M, M --> L, L --> H, L --> M and L --> L were analysed. Odds ratios (ORs) and 95%-confidence intervals [95%-CIs] were estimated with logistic regression models including age, consumption of fruits/vegetables, study centre, smoking and alcohol consumption. The adjusted OR for the lowest versus the highest of three categories (time weighted average of SP) was 1.28 [1.04-1.56]. The distance of SP widened between cases and controls during working life. The downward trajectory H --> L gave an OR of 1.71 [0.75-3.87] as compared to H --> H. Subjects with M --> M and L --> L trajectories ORs were also elevated relative to subjects with H --> H trajectories. The association between SP and UADT is not fully explained by confounding factors. Downward social trajectory during the life course may be an independent risk factor for UADT cancers. PMID:20143252

Schmeisser, N; Conway, D I; McKinney, P A; McMahon, A D; Pohlabeln, H; Marron, M; Benhamou, S; Bouchardy, C; Macfarlane, G J; Macfarlane, T V; Lagiou, P; Lagiou, A; Bencko, V; Holcátová, I; Merletti, F; Richiardi, L; Kjaerheim, K; Agudo, A; Talamini, R; Polesel, J; Canova, C; Simonato, L; Lowry, R; Znaor, A; Healy, C; McCarten, B E; Hashibe, M; Brennan, P; Ahrens, W

2010-03-01

29

Minor salivary gland tumours of upper aerodigestive tract: a clinicopathological study.  

PubMed

The aim of this retrospective study of 56 patients with minor salivary gland tumours (MSGTs) of the upper aerodigestive tract is to present demographic features, distribution of tumours as well as methods and results of treatment performed in our institution over a 10-year period. Of 221 patients with salivary gland tumours, 56 patients with MSGT were selected. There were 36 female and 20 male patients aged from 8 to 81 years. Male-to-female ratio was 1?:?2 in the group of benign MSGT and 1?:?1.7 in the group of malignant tumours. The palate was the most frequent site of MSGT (45.6%), followed by buccal mucosa (19.3%). Of all MSGTs 63.2% were malignant, and 36.8% were benign. Adenoid cystic carcinoma was the most common neoplasm (31.6%), followed by pleomorphic adenoma (29.8%). Surgery was the method of choice in the treatment of patients with MSGT. Postoperative defects were reconstructed by prosthetic obturators, local flaps, and free radial forearm flap. Relative survival for patients with malignant MSGT was 88% at three years and 71.5% at five years. MSGTs are more frequent in females and predominantly affect the palate. Malignant MSGTs are more common than benign. PMID:22675346

Wyszy?ska-Pawelec, Gra?yna; Gontarz, Micha?; Zapa?a, Jan; Szuta, Mariusz

2012-01-01

30

Optimal tracking and testing of U.S. and Canadian herds for BSE: a value-of-information (VOI) approach.  

PubMed

The U.S. Department of Agriculture (USDA) tests a subset of cattle slaughtered in the United States for bovine spongiform encephalitis (BSE). Knowing the origin of cattle (U.S. vs. Canadian) at testing could enable new testing or surveillance policies based on the origin of cattle testing positive. For example, if a Canadian cow tests positive for BSE, while no U.S. origin cattle do, the United States could subject Canadian cattle to more stringent testing. This article illustrates the application of a value-of-information (VOI) framework to quantify and compare potential economic costs to the United States of implementing tracking cattle origins to the costs of not doing so. The potential economic value of information from a tracking program is estimated to exceed its costs by more than five-fold if such information can reduce future losses in export and domestic markets and reduce future testing costs required to reassure or win back customers. Sensitivity analyses indicate that this conclusion is somewhat robust to many technical, scientific, and market uncertainties, including the current prevalence of BSE in the United States and/or Canada and the likely reactions of consumers to possible future discoveries of BSE in the United States and/or Canada. Indeed, the potential value of tracking information is great enough to justify locating and tracking Canadian cattle already in the United States when this can be done for a reasonable cost. If aggressive tracking and testing can win back lost exports, then the VOI of a tracking program may increase to over half a billion dollars per year. PMID:16268932

Cox, Louis Anthony; Popken, Douglas A; VanSickle, John J; Sahu, Ranajit

2005-08-01

31

A sex-specific association between a 15q25 variant and upper aerodigestive tract cancers  

PubMed Central

Background Sequence variants located at 15q25 have been associated with lung cancer and propensity to smoke. We recently reported an association between rs16969968 and risk of upper aerodigestive tract (UADT) cancers (oral cavity, oropharynx, hypopharynx, larynx and esophagus) in women (odds ratio (OR) =1.24, P=0.003) with little effect in men (OR=1.04, P=0.35). Methods In a coordinated genotyping study within the International Head and Neck Cancer Epidemiology (INHANCE) consortium, we have sought to replicate these findings in an additional 4,604 cases and 6,239 controls from 10 independent UADT cancer case-control studies. Results rs16969968 was again associated with UADT cancers in women (OR=1.21, 95% confidence interval(CI)=1.08–1.36, P=0.001) and a similar lack of observed effect in men (OR=1.02, 95%CI=0.95–1.09, P=0.66) (P-heterogeneity=0.01). In a pooled analysis of the original and current studies, totaling 8,572 UADT cancer cases and 11,558 controls, the association was observed among females (OR=1.22, 95%CI=1.12–1.34, P=7×10?6) but not males (OR=1.02, 95%CI=0.97–1.08, P=0.35) (P-heterogeneity=6×10?4). There was little evidence for a sex difference in the association between this variant and cigarettes smoked per day, with male and female rs16969968 variant carriers smoking approximately the same amount more in the 11,991 ever smokers in the pooled analysis of the 14 studies (P-heterogeneity=0.86). Conclusions This study has confirmed a sex difference in the association between the 15q25 variant rs16969968 and UADT cancers. Impact Further research is warranted to elucidate the mechanisms underlying these observations.

Chen, Dan; Truong, Therese; Gaborieau, Valerie; Byrnes, Graham; Chabrier, Amelie; Chuang, Shu-chun; Olshan, Andrew F.; Weissler, Mark C.; Luo, Jingchun; Romkes, Marjorie; Buch, Shama; Nukui, Tomoko; Franceschi, Silvia; Herrero, Rolando; Talamini, Renato; Kelsey, Karl T; Christensen, Brock; McClean, Mike; Lacko, Martin; Manni, Johannes J; Peters, Wilbert H. M.; Lubinski, Jan; Trubicka, Joanna; Lener, Marcin; Muscat, Joshua E.; Lazarus, Philip; Wei, Qingyi; Sturgis, Erich M.; Zhang, Zuo-Feng; Chang, Shen-Chih; Wang, Renyi; Schwartz, Stephen M.; Chen, Chu; Benhamou, Simone; Lagiou, Pagona; Holcatova, Ivana; Richiardi, Lorenzo; Kjaerheim, Kristina; Agudo, Antonio; Castellsague, Xavier; Macfarlane, Tatiana V.; Barzan, Luigi; Canova, Cristina; Thakker, Nalin S; Conway, David I; Znaor, Ariana; Healy, Claire M.; Ahrens, Wolfgang; Zaridze, David; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Fabianova, Eleonora; Bucur, Alexandru; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Curado, Maria Paula; Koifman, Sergio; Menezes, Ana; Wunsch-Filho, Victor; Neto, Jose Eluf; Fernandez, Leticia; Boccia, Stefania; Hashibe, Mia; Hayes, Richard B.; Boffetta, Paolo; Brennan, Paul; McKay, James D.

2011-01-01

32

A Genome-Wide Association Study of Upper Aerodigestive Tract Cancers Conducted within the INHANCE Consortium  

PubMed Central

Genome-wide association studies (GWAS) have been successful in identifying common genetic variation involved in susceptibility to etiologically complex disease. We conducted a GWAS to identify common genetic variation involved in susceptibility to upper aero-digestive tract (UADT) cancers. Genome-wide genotyping was carried out using the Illumina HumanHap300 beadchips in 2,091 UADT cancer cases and 3,513 controls from two large European multi-centre UADT cancer studies, as well as 4,821 generic controls. The 19 top-ranked variants were investigated further in an additional 6,514 UADT cancer cases and 7,892 controls of European descent from an additional 13 UADT cancer studies participating in the INHANCE consortium. Five common variants presented evidence for significant association in the combined analysis (p?5×10?7). Two novel variants were identified, a 4q21 variant (rs1494961, p?=?1×10?8) located near DNA repair related genes HEL308 and FAM175A (or Abraxas) and a 12q24 variant (rs4767364, p?=?2×10?8) located in an extended linkage disequilibrium region that contains multiple genes including the aldehyde dehydrogenase 2 (ALDH2) gene. Three remaining variants are located in the ADH gene cluster and were identified previously in a candidate gene study involving some of these samples. The association between these three variants and UADT cancers was independently replicated in 5,092 UADT cancer cases and 6,794 controls non-overlapping samples presented here (rs1573496-ADH7, p?=?5×10?8; rs1229984-ADH1B, p?=?7×10?9; and rs698-ADH1C, p?=?0.02). These results implicate two variants at 4q21 and 12q24 and further highlight three ADH variants in UADT cancer susceptibility.

McKay, James D.; Truong, Therese; Gaborieau, Valerie; Chabrier, Amelie; Chuang, Shu-Chun; Byrnes, Graham; Zaridze, David; Shangina, Oxana; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Rudnai, Peter; Fabianova, Eleonora; Bucur, Alexandru; Bencko, Vladimir; Holcatova, Ivana; Janout, Vladimir; Foretova, Lenka; Lagiou, Pagona; Trichopoulos, Dimitrios; Benhamou, Simone; Bouchardy, Christine; Ahrens, Wolfgang; Merletti, Franco; Richiardi, Lorenzo; Talamini, Renato; Barzan, Luigi; Kjaerheim, Kristina; Macfarlane, Gary J.; Macfarlane, Tatiana V.; Simonato, Lorenzo; Canova, Cristina; Agudo, Antonio; Castellsague, Xavier; Lowry, Ray; Conway, David I.; McKinney, Patricia A.; Healy, Claire M.; Toner, Mary E.; Znaor, Ariana; Curado, Maria Paula; Koifman, Sergio; Menezes, Ana; Wunsch-Filho, Victor; Neto, Jose Eluf; Garrote, Leticia Fernandez; Boccia, Stefania; Cadoni, Gabriella; Arzani, Dario; Olshan, Andrew F.; Weissler, Mark C.; Funkhouser, William K.; Luo, Jingchun; Lubinski, Jan; Trubicka, Joanna; Lener, Marcin; Oszutowska, Dorota; Schwartz, Stephen M.; Chen, Chu; Fish, Sherianne; Doody, David R.; Muscat, Joshua E.; Lazarus, Philip; Gallagher, Carla J.; Chang, Shen-Chih; Zhang, Zuo-Feng; Wei, Qingyi; Sturgis, Erich M.; Wang, Li-E; Franceschi, Silvia; Herrero, Rolando; Kelsey, Karl T.; McClean, Michael D.; Marsit, Carmen J.; Nelson, Heather H.; Romkes, Marjorie; Buch, Shama; Nukui, Tomoko; Zhong, Shilong; Lacko, Martin; Manni, Johannes J.; Peters, Wilbert H. M.; Hung, Rayjean J.; McLaughlin, John; Vatten, Lars; Nj?lstad, Inger; Goodman, Gary E.; Field, John K.; Liloglou, Triantafillos; Vineis, Paolo; Clavel-Chapelon, Francoise; Palli, Domenico; Tumino, Rosario; Krogh, Vittorio; Panico, Salvatore; Gonzalez, Carlos A.; Quiros, J. Ramon; Martinez, Carmen; Navarro, Carmen; Ardanaz, Eva; Larranaga, Nerea; Khaw, Kay-Tee; Key, Timothy; Bueno-de-Mesquita, H. Bas; Peeters, Petra H. M.; Trichopoulou, Antonia; Linseisen, Jakob; Boeing, Heiner; Hallmans, Goran; Overvad, Kim; Tj?nneland, Anne; Kumle, Merethe; Riboli, Elio; Valk, Kristjan; Voodern, Tonu; Metspalu, Andres; Zelenika, Diana; Boland, Anne; Delepine, Marc; Foglio, Mario; Lechner, Doris; Blanche, Helene; Gut, Ivo G.; Galan, Pilar; Heath, Simon; Hashibe, Mia; Hayes, Richard B.; Boffetta, Paolo; Lathrop, Mark; Brennan, Paul

2011-01-01

33

A genome-wide association study of upper aerodigestive tract cancers conducted within the INHANCE consortium.  

PubMed

Genome-wide association studies (GWAS) have been successful in identifying common genetic variation involved in susceptibility to etiologically complex disease. We conducted a GWAS to identify common genetic variation involved in susceptibility to upper aero-digestive tract (UADT) cancers. Genome-wide genotyping was carried out using the Illumina HumanHap300 beadchips in 2,091 UADT cancer cases and 3,513 controls from two large European multi-centre UADT cancer studies, as well as 4,821 generic controls. The 19 top-ranked variants were investigated further in an additional 6,514 UADT cancer cases and 7,892 controls of European descent from an additional 13 UADT cancer studies participating in the INHANCE consortium. Five common variants presented evidence for significant association in the combined analysis (p ? 5 × 10??). Two novel variants were identified, a 4q21 variant (rs1494961, p?=?1×10??) located near DNA repair related genes HEL308 and FAM175A (or Abraxas) and a 12q24 variant (rs4767364, p =2 × 10??) located in an extended linkage disequilibrium region that contains multiple genes including the aldehyde dehydrogenase 2 (ALDH2) gene. Three remaining variants are located in the ADH gene cluster and were identified previously in a candidate gene study involving some of these samples. The association between these three variants and UADT cancers was independently replicated in 5,092 UADT cancer cases and 6,794 controls non-overlapping samples presented here (rs1573496-ADH7, p = 5 × 10??); rs1229984-ADH1B, p = 7 × 10??; and rs698-ADH1C, p = 0.02). These results implicate two variants at 4q21 and 12q24 and further highlight three ADH variants in UADT cancer susceptibility. PMID:21437268

McKay, James D; Truong, Therese; Gaborieau, Valerie; Chabrier, Amelie; Chuang, Shu-Chun; Byrnes, Graham; Zaridze, David; Shangina, Oxana; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Rudnai, Peter; Fabianova, Eleonora; Bucur, Alexandru; Bencko, Vladimir; Holcatova, Ivana; Janout, Vladimir; Foretova, Lenka; Lagiou, Pagona; Trichopoulos, Dimitrios; Benhamou, Simone; Bouchardy, Christine; Ahrens, Wolfgang; Merletti, Franco; Richiardi, Lorenzo; Talamini, Renato; Barzan, Luigi; Kjaerheim, Kristina; Macfarlane, Gary J; Macfarlane, Tatiana V; Simonato, Lorenzo; Canova, Cristina; Agudo, Antonio; Castellsagué, Xavier; Lowry, Ray; Conway, David I; McKinney, Patricia A; Healy, Claire M; Toner, Mary E; Znaor, Ariana; Curado, Maria Paula; Koifman, Sergio; Menezes, Ana; Wünsch-Filho, Victor; Neto, José Eluf; Garrote, Leticia Fernández; Boccia, Stefania; Cadoni, Gabriella; Arzani, Dario; Olshan, Andrew F; Weissler, Mark C; Funkhouser, William K; Luo, Jingchun; Lubi?ski, Jan; Trubicka, Joanna; Lener, Marcin; Oszutowska, Dorota; Schwartz, Stephen M; Chen, Chu; Fish, Sherianne; Doody, David R; Muscat, Joshua E; Lazarus, Philip; Gallagher, Carla J; Chang, Shen-Chih; Zhang, Zuo-Feng; Wei, Qingyi; Sturgis, Erich M; Wang, Li-E; Franceschi, Silvia; Herrero, Rolando; Kelsey, Karl T; McClean, Michael D; Marsit, Carmen J; Nelson, Heather H; Romkes, Marjorie; Buch, Shama; Nukui, Tomoko; Zhong, Shilong; Lacko, Martin; Manni, Johannes J; Peters, Wilbert H M; Hung, Rayjean J; McLaughlin, John; Vatten, Lars; Njølstad, Inger; Goodman, Gary E; Field, John K; Liloglou, Triantafillos; Vineis, Paolo; Clavel-Chapelon, Francoise; Palli, Domenico; Tumino, Rosario; Krogh, Vittorio; Panico, Salvatore; González, Carlos A; Quirós, J Ramón; Martínez, Carmen; Navarro, Carmen; Ardanaz, Eva; Larrañaga, Nerea; Khaw, Kay-Tee; Key, Timothy; Bueno-de-Mesquita, H Bas; Peeters, Petra H M; Trichopoulou, Antonia; Linseisen, Jakob; Boeing, Heiner; Hallmans, Göran; Overvad, Kim; Tjønneland, Anne; Kumle, Merethe; Riboli, Elio; Välk, Kristjan; Vooder, Tõnu; Voodern, Tõnu; Metspalu, Andres; Zelenika, Diana; Boland, Anne; Delepine, Marc; Foglio, Mario; Lechner, Doris; Blanché, Hélène; Gut, Ivo G; Galan, Pilar; Heath, Simon; Hashibe, Mia; Hayes, Richard B; Boffetta, Paolo; Lathrop, Mark; Brennan, Paul

2011-03-01

34

Two BRM promoter insertion polymorphisms increase the risk of early-stage upper aerodigestive tract cancers.  

PubMed

Brahma (BRM) has a key function in chromatin remodeling. Two germline BRM promoter insertion-deletion polymorphisms, BRM-741 and BRM-1321, have been previously associated with an increased risk of lung cancer in smokers and head and neck cancer. To further evaluate their role in cancer susceptibility particularly in early disease, we conducted a preplanned case-control study to investigate the association between the BRM promoter variants and stage I/II upper aerodigestive tract (UADT) cancers (i.e., lung, esophageal, head and neck), a group of early-stage malignancies in which molecular and genetic etiologic factors are poorly understood. The effects of various clinical factors on this association were also studied. We analyzed 562 cases of early-stage UADT cancers and 993 matched healthy controls. The double homozygous BRM promoter variants were associated with a significantly increased risk of early stage UADT cancers (adjusted odds ratio [aOR], 2.46; 95% confidence interval [CI], 1.7-3.8). This association was observed in lung (aOR, 2.61; 95% CI, 1.5-4.9) and head and neck (aOR, 2.75; 95% CI, 1.4-5.6) cancers, but not significantly in esophageal cancer (aOR, 1.66; 95% CI, 0.7-5.8). There was a nonsignificant trend for increased risk in the heterozygotes or single homozygotes. The relationship between the BRM polymorphisms and early-stage UADT cancers was independent of age, sex, smoking status, histology, and clinical stage. These findings suggest that the BRM promoter double insertion homozygotes may be associated with an increased risk of early-stage UADT cancers independent of smoking status and histology, which must be further validated in other populations. PMID:24519853

Wong, Kit Man; Qiu, Xiaoping; Cheng, Dangxiao; Azad, Abul Kalam; Habbous, Steven; Palepu, Prakruthi; Mirshams, Maryam; Patel, Devalben; Chen, Zhuo; Roberts, Heidi; Knox, Jennifer; Marquez, Stephanie; Wong, Rebecca; Darling, Gail; Waldron, John; Goldstein, David; Leighl, Natasha; Shepherd, Frances A; Tsao, Ming; Der, Sandy; Reisman, David; Liu, Geoffrey

2014-04-01

35

Lifetime risk of distinct upper aerodigestive tract cancers and consumption of alcohol, betel and cigarette.  

PubMed

The cancer of upper aerodigestive tract (UADT) is a common cancers in the world. However, its lifetime risk by consumption of alcohol, betel and cigarettes remain to be elucidated. This study aimed to estimate lifetime risk of distinct UADT cancers and assess their associations with alcohol, betel and cigarette consumption. Three cohorts of 25,611 men were enrolled in 1982-1992 in Taiwan. The history of alcohol, betel and cigarette consumption was enquired through questionnaire interview. Newly developed UADT cancers were ascertained through computerized linkage with national cancer registry profile. Lifetime (30-80 years old) risk and multivariate-adjusted hazard ratio (HRadj ) of distinct UADT cancers by alcohol, betel and cigarette consumption were estimated. A total of 269 pathologically confirmed cases of UADT cancers were newly-diagnosed during 472,096 person-years of follow-up. The lifetime risk of UADT cancer was 9.42 and 1.65% for betel chewers and nonchewers, 3.22 and 1.21% for cigarette smokers and nonsmokers and 4.77 and 1.85% for alcohol drinkers and nondrinkers. The HRadj (95% confidence interval) of developing UADT cancer was 3.36 (2.51-4.49), 2.02 (1.43-2.84), 1.90 (1.46-2.49), respectively, for the consumption of betel, cigarette and alcohol. Alcohol, betel and cigarette had different effect on cancers at various anatomical sites of UADT. The cancer risk from the mouth, pharynx, esophagus to larynx increased for alcohol and cigarette consumption, but decreased for betel consumption. Alcohol, betel and cigarette consumption are independent risk predictors for distinct UADT cancers. PMID:24535776

Hsu, Wan-Lun; Chien, Yin-Chu; Chiang, Chun-Ju; Yang, Hwai-I; Lou, Pei-Jen; Wang, Cheng-Ping; Yu, Kelly J; You, San-Lin; Wang, Li-Yu; Chen, Shu-Yuan; Yang, Czau-Siung; Chen, Chien-Jen

2014-09-15

36

Coffee and green tea consumption is associated with upper aerodigestive tract cancer in Japan.  

PubMed

The impact of coffee and green tea consumption on upper aerodigestive tract (UADT) cancer risk has not been established. Evaluation of the possible anticarcinogenic properties of their ingredients is confounded by the potential increase in risk owing to the high temperatures at which these beverages are generally consumed. We conducted a case-control study to evaluate the association between coffee and tea consumption and the risk of UADT cancer. The study enrolled 961 patients with UADT cancer and 2,883 noncancer outpatients who visited Aichi Cancer Center between 2001 and 2005. Information on coffee and green tea consumption and other lifestyle factors was collected via a self-administered questionnaire. Consumption of three or more cups of coffee per day had a significant inverse association with UADT cancer [odds ratio (OR) 0.73, 95% confidence interval (CI) 0.55-0.96]. In contrast, consumption of three or more cups of green tea per day had a significant positive association with UADT cancer (OR 1.39, 95% CI 1.13-1.70). These associations were evident for head and neck cancer but not for esophageal cancer. The association of coffee consumption with head and neck cancer was observed only among never smokers and alcohol drinkers. Similarly, the association of green tea consumption was observed among never smokers and never alcohol drinkers. No change in these associations was seen on stratification by each confounding factors. These findings suggest that consumption of coffee might be associated with a decreased risk of UADT cancer, whereas that of green tea might be associated with an increased risk. PMID:24310779

Oze, Isao; Matsuo, Keitaro; Kawakita, Daisuke; Hosono, Satoyo; Ito, Hidemi; Watanabe, Miki; Hatooka, Shunzo; Hasegawa, Yasuhisa; Shinoda, Masayuki; Tajima, Kazuo; Tanaka, Hideo

2014-07-15

37

A functional trinucleotide repeat polymorphism in the 5'-untranslated region of the glutathione biosynthetic gene GCLC is associated with increased risk for lung and aerodigestive tract cancers.  

PubMed

Glutathione (GSH), the major intracellular antioxidant, protects against cancer development by detoxifying carcinogens and free radicals and strengthening the immune system. Recently, a GAG-trinucleotide repeat polymorphism in the 5'-untranslated region of the gene for the rate-limiting enzyme for GSH biosynthesis, ?-glutamine cysteine ligase (GCL), was shown to be associated with lowered GCL activity and GSH levels in vitro and in vivo. We tested the hypothesis that this functional polymorphism in GCL is associated with the risk for lung and aerodigestive tract cancers. To this end, we conducted a case-control study that included 375 lung cancer cases, 200 aerodigestive tract cancer cases, and 537 controls. GAG repeat genotype (4, 7, 8, 9, and 10 repeat alleles) was determined by capillary electrophoresis of PCR products from the repeat region of the GCL catalytic subunit (GCLC). Odds ratios (OR) were calculated by logistic regression and adjusted for risk factors, including age, sex, body mass index, and smoking history. The GAG-7/7 genotype was associated with a 1.9-fold increased risk of lung cancer and 2.6-fold increased risk of aerodigestive tract cancer compared to the wild-type GAG-9/9 (P?aerodigestive tract cancer (OR?=?2.3, P?aerodigestive tract cancers, and further implicates a role for oxidative stress in the development of these cancers. PMID:22610501

Nichenametla, Sailendra N; Muscat, Joshua E; Liao, Jason G; Lazarus, Philip; Richie, John P

2013-10-01

38

Shah Gail (2009) HPC covers large number neoplasms arising one anatomic region included tumors mucosa upper aerodigestive tract including oral cavity Bronx larynx minuses. included tumors silvery glands thyroid soft tissue bone tumors skin cancers  

EPA Pesticide Factsheets

Did you mean: Shah Gail (2009) HPC covers large number neoplasms arising one anatomic region included tumors mucosa upper aerodigestive tract including oral cavity Bronx larynx minuses. included tumors silvery glands thyroid soft tissue bone tumors skin cancers ?

39

Marijuana Use and the Risk of Lung and Upper Aerodigestive Tract Cancers: Results of a Population-Based Case-Control Study  

Microsoft Academic Search

Background: Despite several lines of evidence suggesting the biological plausibility of marijuana being carcinogenic, epidemiologic findings are inconsistent. We conducted a population-based case-control study of the association between marijuana use and the risk of lung and upper aerodigestive tract cancers in Los Angeles. Methods: Our study included 1,212 incident cancer cases and 1,040 cancer-free controls matched to cases on age,

Mia Hashibe; Hal Morgenstern; Yan Cui; Donald P. Tashkin; Zuo-Feng Zhang; Wendy Cozen; Thomas M. Mack; Sander Greenland

2006-01-01

40

Squamous cell carcinoma variants of the upper aerodigestive tract: a comprehensive review with a focus on genetic alterations.  

PubMed

Context.- Squamous cell carcinoma of the upper aerodigestive tract is a heterogenous entity. Although conventional squamous cell carcinomas are easily recognized, the morphologic variants of squamous cell carcinoma can present a diagnostic challenge. Familiarity with these variants is necessary because many are associated with unique risk factors and are characterized by specific molecular alterations (eg, nuclear protein in testis midline carcinomas). Perhaps the most important distinction is in identifying viral-related from nonviral-related carcinomas. The accurate diagnosis of these variants is necessary for prognostic and therapeutic reasons. Objectives.- To provide a clinicopathologic overview and summary of the molecular alterations of the common squamous cell carcinoma variants, including verrucous, spindle cell, acantholytic, adenosquamous, basaloid, and papillary squamous cell carcinoma, as well as nuclear protein in testis midline carcinoma, and to discuss the distinguishing features of human papillomavirus- and Epstein-Barr virus-related squamous cell carcinomas. Data Sources.- Published peer-reviewed literature. Conclusions.- Familiarity with squamous cell carcinoma variants is essential for proper diagnosis and to guide appropriate clinical management. Further insight into the molecular alterations underlying those variants may lead to alterations in existing treatment approaches and to evolution of novel treatment modalities. PMID:24878013

Shah, Akeesha A; Jeffus, Susanne K; Stelow, Edward B

2014-06-01

41

Toys in the upper aerodigestive tract: new evidence on their risk as emerging from the Susy Safe Study.  

PubMed

Foreign body (FB) inhalation, aspiration or ingestion are relatively common events in children. Despite many efforts made in several countries to achieve acceptable safety levels for consumer products devoted to children, small toys or toy parts are still frequently mentioned among risky foreign bodies. The aim of the present study is to characterize the risk of complications and prolonged hospitalization due to toys inhalation, aspiration or ingestion according to age and gender of patients, FB characteristics, circumstances of the accident, as emerging from the Susy Safe Registry. The Susy Safe Registry started in the 2005 to collect data to serve as a basis for a knowledge-based consumer protection activity. It is actually one of the wider databases collecting foreign body injuries in the upper aero-digestive tract in pediatric patients. It is distinguished by a deep characterization of objects which caused the injuries and a multi-step quality control procedure which assures its reliability. Preventive strategies imposing a regulation of industrial production, even if fundamental, are not sufficient and need to be integrated along with other intervention addressed to make aware caregivers toward a proper surveillance of children. PMID:22361527

Foltran, Francesca; Passali, Francesco Maria; Berchialla, Paola; Gregori, Dario; Pitkäranta, Anne; Slapak, Ivo; Jakubíková, Janka; Franchin, Laura; Ballali, Simonetta; Passali, Giulio Cesare; Bellussi, Luisa; Passali, Desiderio

2012-05-14

42

Active and involuntary tobacco smoking and upper-aerodigestive-tract cancer risks in a multicenter case-control study  

PubMed Central

Introduction Several important issues for the established association between tobacco smoking and upper-aerodigestive tract (UADT) cancer risks include the associations with smoking by cancer subsite, by type of tobacco, and among never alcohol drinkers, and the associations with involuntary smoking among nonsmokers. Our aim was to examine these specific issues in a large scale case-control study in Europe. Methods Analysis was performed on 2,103 UADT squamous cell carcinoma cases and 2,221 controls in the Alcohol-Related Cancers and Genetic Susceptibility in Europe (ARCAGE) project, a multicenter case-control study in 10 European countries. Unconditional logistic regression was performed to obtain odds ratios (OR) and 95% confidence intervals (CI). Results Compared to never tobacco smoking, current smoking was associated with UADT cancer risks (OR=6.72, 95% CI 5.45–8.30 for overall; 5.83, 4.50–7.54 for oral cavity and oropharynx; 12.19, 8.29–17.92 for hypopharynx and larynx; 4.17, 2.45–7.10 for esophagus). Among never drinkers, dose-response relationships with tobacco smoking packyears were observed for hypopharyngeal and laryngeal cancers (ptrend = 0.01), but not for oral cavity and oropharyngeal cancers (ptrend = 0.282). Among never smokers, ever exposure to involuntary smoking was associated with an increased risk of UADT cancers (OR=1.60, 95% CI 1.04–2.46). Conclusion Our results corroborate that tobacco smoking may play a stronger role in the development of hypopharyngeal and laryngeal cancers than that of oral cavity and oropharyngeal cancers among never drinkers and that involuntary smoking is an important risk factor for UADT cancers. Public health interventions to reduce involuntary smoking exposure could help reduce UADT cancer incidence.

Lee, Yuan-Chin Amy; Marron, Manuela; Benhamou, Simone; Bouchardy, Christine; Ahrens, Wolfgang; Pohlabeln, Hermann; Lagiou, Pagona; Trichopoulos, Dimitrios; Agudo, Antonio; Castellsague, Xavier; Bencko, Vladimir; Holcatova, Ivana; Kjaerheim, Kristina; Merletti, Franco; Richiardi, Lorenzo; Macfarlane, Gary J.; Macfarlane, Tatiana V.; Talamini, Renato; Barzan, Luigi; Canova, Cristina; Simonato, Lorenzo; Conway, David I.; McKinney, Patricia A.; Lowry, Raymond J.; Sneddon, Linda; Znaor, Ariana; Healy, Claire M.; McCartan, Bernard E.; Brennan, Paul; Hashibe, Mia

2012-01-01

43

Smoking addiction and the risk of upper-aerodigestive-tract cancer in a multicenter case-control study.  

PubMed

Although previous studies on tobacco and alcohol and the risk of upper-aerodigestive-tract (UADT) cancers have clearly shown dose-response relations with the frequency and duration of tobacco and alcohol, studies on addiction to tobacco smoking itself as a risk factor for UADT cancer have not been published, to our knowledge. The aim of this report is to assess whether smoking addiction is an independent risk factor or a refinement to smoking variables (intensity and duration) for UADT squamous cell carcinoma (SCC) risk in the multicenter case-control study (ARCAGE) in Western Europe. The analyses included 1,586 ever smoking UADT SCC cases and 1,260 ever smoking controls. Addiction was measured by a modified Fagerström score (first cigarette after waking up, difficulty refraining from smoking in places where it is forbidden and cigarettes per day). Adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for UADT cancers with addiction variables were estimated with unconditional logistic regression. Among current smokers, the participants who smoked their first cigarette within 5 min of waking up were two times more likely to develop UADT SCC than those who smoked 60 min after waking up. Greater tobacco smoking addiction was associated with an increased risk of UADT SCC among current smokers (OR = 3.83, 95% CI: 2.56-5.73 for score of 3-7 vs. 0) but not among former smokers. These results may be consistent with a residual effect of smoking that was not captured by the questionnaire responses (smoking intensity and smoking duration) alone, suggesting addiction a refinement to smoking variables. PMID:23719996

Lee, Yuan-Chin Amy; Zugna, Daniela; Richiardi, Lorenzo; Merletti, Franco; Marron, Manuela; Ahrens, Wolfgang; Pohlabeln, Hermann; Lagiou, Pagona; Trichopoulos, Dimitrios; Agudo, Antonio; Castellsague, Xavier; Betka, Jaroslav; Holcatova, Ivana; Kjaerheim, Kristina; Macfarlane, Gary J; Macfarlane, Tatiana V; Talamini, Renato; Barzan, Luigi; Canova, Cristina; Simonato, Lorenzo; Conway, David I; McKinney, Patricia A; Thomson, Peter; Znaor, Ariana; Healy, Claire M; McCartan, Bernard E; Boffetta, Paolo; Brennan, Paul; Hashibe, Mia

2013-12-01

44

Glutathione S-transferase M1 or T1 null genotype as a risk factor for developing multiple primary neoplasms in the upper aero-digestive tract, in Indian males using tobacco  

Microsoft Academic Search

In this study conducted amongst Indian male tobacco users with upper aero-digestive tract (UADT) squamous carcinoma, 30 patients with multiple primary neoplasms (MPN) were compared with 28 age and sex matched patients with a single primary neoplasm (SPN) for various environmental factors (form of tobacco use, alcohol, radiotherapy for index cancer) and genetic parameters (family history of UADT cancers and

Sameer Jhavar; Rajiv Sarin; Rita Mulherkar; Axel Benner; Jai Prakash Agarwal; Ketayun Dinshaw

2004-01-01

45

Human papillomavirus-positive basaloid squamous cell carcinomas of the upper aerodigestive tract: a distinct clinicopathologic and molecular subtype of basaloid squamous cell carcinoma?  

PubMed Central

Summary Basaloid squamous cell carcinoma of the upper aerodigestive tract is a rare, morphologically distinct variant of squamous cell carcinoma that is thought to be clinically aggressive. The histologic features are distinct from, but often confused with, those of human papillomavirus–related oropharyngeal nonkeratinizing squamous cell carcinoma. The role of human papillomavirus as an etiologic agent in true basaloid squamous cell carcinoma is controversial. The purpose of this study was to determine human papillomavirus prevalence and its clinicopathologic significance in upper aerodigestive tract tumors with true basaloid squamous cell carcinoma histology. Twenty-eight cases were identified, 12 in the oropharynx and 16 in the larynx and/or hypopharynx. High-risk human papillomavirus in situ hybridization and immunohistochemistry for p16 and p53 were performed. Nine (75%) of the oropharyngeal and none of the larynx/hypopharynx tumors were human papillomavirus positive. Human papillomavirus–positive tumors affected younger patients. No significant statistical differences in patients’ sex, tumor stage, treatment modality, or length of follow-up were observed between the 2 groups. Viral status showed a strong, positive correlation with p16 (P < .001) and a strong, negative correlation with p53 (P < .0001) immunoreactivity. Overall survival was better for human papillomavirus–positive basaloid squamous cell carcinomas (P < .05), with 86% of patients alive at 3 years compared with 35.3% of patients with human papillomavirus–negative tumors. These findings suggest that a subset of basaloid squamous cell carcinomas is virally driven. These tumors occur almost exclusively in the oropharynx, are molecularly distinct from their human papillomavirus–negative counterparts, and have a more favorable clinical outcome.

Chernock, Rebecca D.; Lewis, James S.; Zhang, Qin; El-Mofty, Samir K.

2013-01-01

46

Early or Up-Front Radiotherapy Improved Survival of Localized Extranodal NK/T-Cell Lymphoma, Nasal-Type in the Upper Aerodigestive Tract  

SciTech Connect

Purpose: To investigate the role of early or up-front radiotherapy (RT), the optimal RT dose required to achieve appropriate treatment outcome and prognostic factors for patients with localized extranodal NK/T-cell lymphoma, nasal-type, in the upper aerodigestive tract. Methods and Materials: Eighty-two patients were reviewed. Eight patients were treated with chemotherapy (CT) alone, 9 patients received RT alone, and 65 patients were given combined modality treatment of CT and RT (CMT). Of those 74 patients receiving RT, 31 patients were given up-front RT, whereas CT was the initial therapy for 43 patients and 41 of those 43 patients received early RT. Results: Five-year overall survival (OS) and disease-free survival (DFS) were 52.3% and 39.2%, respectively. RT was the only independent prognostic factor for both OS and DFS at both the univariate and multivariate level. The 5-year OS and DFS were better in patients receiving {>=}54 Gy of RT as compared with that of <54 Gy (5-year OS 75.5% vs. 46.1%, p = 0.019; 5-year DFS 60.3% vs. 33.4%, p = 0.004). Up-front RT presented better survival in Stage I patients when compared with that of initial CT followed by early RT (5-year OS 90.0% vs. 48.9%, p = 0.012; 5-year DFS 78.7% vs. 39.9%, p = 0.021). Conclusion: Early or up-front RT had an essential role in improved OS and DFS in patients with localized extranodal NK/T-cell lymphoma, nasal-type, in the upper aerodigestive tract. The recommended tumor dose was at least 54 Gy. Up-front RT may yield more benefits on survival in patients with Stage I disease.

Huang Meijuan; Jiang Yu [Department of Biotherapy for Cancer, West China Hospital, Medical School, Sichuan University, Chengdu (China); State Key Laboratory of Biotherapy, West China Hospital, Medical School, Sichuan University, Chengdu (China); Liu Weiping [Department of Pathology, West China Hospital, Medical School, Sichuan University, Chengdu (China); Li Zhiping [Department of Radiotherapy for Cancer, West China Hospital, Medical School, Sichuan University, Chengdu (China); Li Mei; Zhou Lin [Department of Biotherapy for Cancer, West China Hospital, Medical School, Sichuan University, Chengdu (China); Xu Yong [Department of Radiotherapy for Cancer, West China Hospital, Medical School, Sichuan University, Chengdu (China); Yu Chunhua [Department of Biotherapy for Cancer, West China Hospital, Medical School, Sichuan University, Chengdu (China); Li Qiu; Peng Feng; Liu Jiyan; Luo Feng [Department of Biotherapy for Cancer, West China Hospital, Medical School, Sichuan University, Chengdu (China); State Key Laboratory of Biotherapy, West China Hospital, Medical School, Sichuan University, Chengdu (China); Lu You [Department of Biotherapy for Cancer, West China Hospital, Medical School, Sichuan University, Chengdu (China); State Key Laboratory of Biotherapy, West China Hospital, Medical School, Sichuan University, Chengdu (China)], E-mail: radyoulu@hotmail.com

2008-01-01

47

Structural evolution of the Day Nui Con Voi metamorphic complex: Implications on the development of the Red River Shear Zone, Northern Vietnam  

NASA Astrophysics Data System (ADS)

The Day Nui Con Voi (DNCV) metamorphic complex in North Vietnam is the southernmost high-grade metamorphic zone along the NW-SE trending Red River Shear Zone (RRSZ) in Indochina. The RRSZ was considered as a classical large-scale continental strike-slip fault that had played a significant role in the continental extrusion of Southeast Asia since the collision of India and Eurasia. Earlier ideas determined the RRSZ as a steep shear zone that penetrated the entire lithosphere. Both metamorphism and structures within rocks along the DNCV metamorphic complex have been previously thought to be formed syn-tectonically by left-lateral shearing of the RRSZ during the Oligocene-Miocene continental escape tectonics. However, our meso- and microstructural re-examination of this region shows that these metamorphic rocks were formed during earlier tectonic episodes unrelated to strike-slip shearing. High angle to near orthogonal overprinting fabrics indicated that this region recorded three episodes of ductile deformation followed by brittle faulting events with different intensity spanning from the Triassic to the Tertiary. D 1 is preserved as NW-SE striking upright folds under garnet grade regional metamorphism during the Triassic Indosinian orogeny as South China block amalgamated with the Indochina block. The large-scale horizontal D 2 folds with a dominant top to N-NW bottom to S-SW sense of shear, and sub-horizontal fold axial planes suggest that the DNCV metamorphic complex remained at midcrustal depths since the Indosinian orogeny. The youngest ductile deformation event, D 3, refolded D 2 recumbent folds into a dome, and uplifted the DNCV as lower-temperature fabrics, S 3, indicated. Steep mylonite zones with left-lateral kinematic indicators and brittle faulting were developed on both limbs of the dome along the steep Song Hong and Song Chay faults during left-lateral movement of the RRSZ. Our new spatial, temporal and kinematic correlations of metamorphic fabrics within the DNCV metamorphic complex support the suggestion that the RRSZ developed after regional metamorphism and remained purely a crustal fault. The complicated deformation history recorded within the DNCV metamorphic complex provides an alternative interpretation and suggests that crustal scale strike-slip faults (such as the RRSZ) need not root from the mantle.

Yeh, Meng-Wan; Lee, Tung-Yi; Lo, Ching-Hua; Chung, Sun-Lin; Lan, Ching-Ying; Anh, Tran Tuan

2008-12-01

48

NAT2, XRCC1 and hOGG1 Polymorphisms, Cigarette Smoking, Alcohol Consumption and Risk of Upper Aerodigestive Tract Cancer.  

PubMed

Aim: To evaluate associations between polymorphisms of the N-acetyltransferase 2 (NAT2), human 8-oxoguanine glycosylase 1 (hOGG1) and X-ray repair cross-complementing protein 1 (XRCC1) genes and risk of upper aerodigestive tract (UADT) cancer. Patients and Methods: A case-control study involving 117 cases and 224 controls was undertaken. The NAT2 gene polymorphisms were genotyped by automated sequencing and XRCC1 Arg399Gln and hOGG1 Ser326Cys polymorphisms were determined by Polymerase Chain Reaction followed by Restriction Fragment Length Polymorphism (PCR-RFLP) methods. Results: Slow metabolization phenotype was significantly associated as a risk factor for the development of UADT cancer (p=0.038). Furthermore, haplotype of slow metabolization was also associated with UADT cancer (p=0.014). The hOGG1 Ser326Cys polymorphism (CG or GG vs. CC genotypes) was shown as a protective factor against UADT cancer in moderate smokers (p=0.031). The XRCC1 Arg399Gln polymorphism (GA or AA vs. GG genotypes), in turn, was a protective factor against UADT cancer only among never-drinkers (p=0.048). Conclusion: Interactions involving NAT2, XRCC1 Arg399Gln and hOGG1 Ser326Cys polymorphisms may modulate the risk of UADT cancer in this population. PMID:24922697

Marques, Cintia Rodrigues; DA Silva, Thiago Magalhães; DE Albuquerque, Dulcineia Martins; Chaves, Meiryane Santos; Filho, Marcilio Ferreira Marques; Oliveira, Jamille Silva; DI Pietro, Giuliano; Sousa, Sandra Mara Bispo; Simões, Aguinaldo Luiz; Rios-Santos, Fabrício

2014-06-01

49

Tag single nucleotide polymorphisms of alcohol-metabolizing enzymes modify the risk of upper aerodigestive tract cancers: HapMap database analysis.  

PubMed

Although alcohol is associated with higher upper aerodigestive tract (UADT) cancer risk, only a small fraction of alcoholics develop cancers. There is a lack of evidence proving the association of tag single nucleotide polymorphisms of alcohol-metabolizing enzymes with cancer risk. The aim of this study was to determine the association of these genetic polymorphisms with UADT cancer risk in a Chinese population. It was a hospital-based case-control candidate gene study. The databases of the International HapMap Project were searched for haplotype tag single nucleotide polymorphisms of the genes alcohol dehydrogenase (ADH)1B, ADH1C, and aldehyde dehydrogenase (ALDH)2. The genotyping was performed by the Sequenom MassARRAY system. Totally, 120 head and neck squamous cell carcinoma, 138 esophageal squamous cell carcinoma patients, and 276 age- and gender-matched subjects were enrolled between June 2008 and June 2010.Minor alleles of ADH1B (rs1229984) and ALDH2(rs671) were not only associated with the risk of UADT cancers (odds ratio [OR] [95% confidence interval, CI]: 3.53 [2.14-5.80] and 2.59 [1.79-3.75], respectively) but also potentiated the carcinogenic effects of alcohol (OR [95% CI]: 53.44 [25.21-113.29] and 70.08 [33.65-145.95], respectively). Similar effects were observed for head/neck and esophageal cancer subgroups. Multivariate logistic regression analysis identified four significant risk factors, including habitual use of cigarettes, alcohol, betel quid, and lower body mass index (P < 0.001). The haplotypes GAGC (OR 1.61, 95% CI 1.08-2.40, P = 0.018) and CCAATG (OR 1.69, 95% CI 1.24-2.30, P < 0.001) on chromosomes 4 and 12, respectively, were associated with higher cancer risk. These findings suggested that risk allele or haplotype carriers who consume alcohol and other carcinogens should be advised to undergo endoscopy screening. The information can be used to determine the degree of susceptibility of each subject and can be combined with other environmental factors, like carcinogen consumption, in the screening analysis. PMID:23088731

Chung, C-S; Lee, Y-C; Liou, J-M; Wang, C-P; Ko, J-Y; Lee, J-M; Wu, M-S; Wang, H-P

2014-07-01

50

Movement Disorder Emergencies of the Upper Aerodigestive Tract  

Microsoft Academic Search

A 52-year-old man was transferred to the emergency room of a major hospital from a referral facility because of recent slurred\\u000a speech. He had been admitted to the facility the week before for treatment of alcohol abuse. Upon his arrival in the emergency\\u000a room, the neurology resident was called to evaluate the patient after a normal computed tomography scan was

Boris Bentsianov; Ajay Chitkara; Anthony Cultrara; Andrew Blitzer

51

Le francais fonde sur la competence, Superieur (Competency Based French, Superior).  

ERIC Educational Resources Information Center

This instructional guide in French is intended for training Peace Corps volunteers serving in the Central African Republic. It includes 35 topical units at the superior level, each consisting of briefly stated competency objectives and a number of brief, related situational texts. Unit topics include: explaining how to do something; explaining…

Dimanche, Maurice

52

L'enseignement superieur tunisien: Enjeux et avenir (Higher Education in Tunisia: Challenges and Opportunities).  

ERIC Educational Resources Information Center

This report presents findings of a study of higher education in Tunisia. It finds that higher education in Tunisia is a largely effective and well-performing system. However, it notes an expected doubling of enrollment over the next 10 years which will create obstacles that prevent it from playing the role expected of it by a society and economy…

World Bank, Washington, DC.

53

From "Ecoles Superieures de Commerce" to "Management Schools": Transformations and Continuity in French Business Schools  

ERIC Educational Resources Information Center

Part of the national system of grandes Ecoles, French Business schools have known radical changes since the 1980s, notably in size, and have become more attractive to students both at a national and an international level. As a consequence, the French elitist system has been questioned by the competition of foreign--especially Anglo-Saxon--models.…

Blanchard, Marianne

2009-01-01

54

L'Enseignement Superieur en Union Sovietique. Analyse Structurelle et Statistique.  

ERIC Educational Resources Information Center

In order to measure the educational achievements of the Soviet Union, it is essential to analyze the educational system in the light of the original intentions and ambitions. The system has three main features, which are a new conception of the relationship between investment and education, an ideological basis and the fact that it is a planned…

Revenko, Tamara

55

Prise en charge des mucites après radiothérapie des cancers des voies aérodigestives supérieures  

Microsoft Academic Search

Acute mucositis is common after radiotherapy for head and neck cancers. Duringthepast3 decades, there was a gradual evolution in the treatment modalities for locally advanced carcinomas (concomitant radio-chemotherapy, accelerated radiotherapy). These new strategies are accompanied by an increase in early mucosal reactions. Atthe present time, there is no widely accepted prophylaxis or effective treatment. Many traditional remedies or new agents

M. Lapeyre; C. Charra-Brunaud; M. C. Kaminsky; L. Geoffrois; G. Dolivet; B. Toussaint; F. Maire; N. Pourel; M. Simon; C. Marchal; P. Bey

2001-01-01

56

La croissance des PME par le biais des ressources et compétences : quelles voies ?  

Microsoft Academic Search

Les PME sont des organisations particulières, bien différentes par rapport à la grande entreprise. Les PME en croissance sont vues comme des vrais leviers pour la création d'emploi et de richesse dans une économie. La croissance des PME est alimentée soit par les nouvelles ressources générées dans l'entreprise pendant le processus de croissance, soit par l'apport externe des ressources (par

A. E Popa Postariu

2010-01-01

57

MRI-PET Correlation in Three Dimensions Using a Volume-of-Interest (VOI) Atlas  

Microsoft Academic Search

Summary: Quantitative interpretation of functional images (PET or SPECT) is hampered by poor spatial resolution, low counting statistics, and, for many tracers, low contrast between different brain structures of interest. Furthermore, normal tracer distributions can be severely disrupted by such gross pathologies as stroke, tumor, and dementia. Hence, the complementary anatomical information provided by CT or MRI is essential for

A. C. Evans; S. Marrett; J. Torrescorzo; S. Ku; L. Collins

1991-01-01

58

Voies inelastiques dans les experiences nucleon-nucleon. (Inelastic events in nucleon-nucleon scattering experiments).  

National Technical Information Service (NTIS)

The phenomenological aspects of the inelastic event occurring in the nucleon-nucleon scattering, are analyzed. The Saturne experiment specific possibilities. (NN(yields)NN(pi), NN(yields)NN(eta), NN(yields)NN(pi) (pi)), are underlined. (ERA citation 15:03...

F. Wellers

1989-01-01

59

Unusual causes of fatal upper aerodigestive tract obstruction in wild Bottlenose Dolphins (Tursiops aduncus).  

PubMed

Necropsy examination of dolphins living in Gulf St Vincent, Australia is routinely undertaken to enable the evaluation of disease processes and to provide rapid medicolegal assessment of any inflicted and/or accidental injuries. Two Indo-Pacific Bottlenose Dolphins (Tursiops aduncus) are reported to demonstrate conditions that may result in unexpected death involving upper airway compromise by quite unusual mechanisms. In the first case an adult male was found with extensive soft tissue trauma suggesting human interaction. At necropsy, death was due instead to upper airway obstruction from an impacted Slender-spined Porcupine Fish (Diodon nichthemerus) in the posterior pharynx and upper esophagus. In the second case, an adult male dolphin was found to have died, following several weeks' illness, from upper airway obstruction due to extensive respiratory tract papillomatosis within the blowhole. Given the infectious etiology of this condition the local population will be monitored for similar lesions. These cases demonstrate rare causes of upper airway obstruction in wild dolphins that were identifiable only after detailed necropsy examination. The possibility of human involvement in the deaths could be excluded. PMID:20165933

Byard, Roger W; Tomo, Ikuko; Kemper, Catherine M; Gibbs, Susan E; Bossley, Mike; Machado, Aaron; Hill, Mark

2010-09-01

60

Effects of alcohol and tobacco on aerodigestive cancer risks: a meta-regression analysis  

Microsoft Academic Search

Objective: Meta-analysis was used to summarize the published evidence on the associations between alcohol and tobacco consumption and cancers of the oropharynx, pharynx, larynx, and esophagus. The objective was to produce summary risk estimates with uniform methods and on uniform exposure scales so that the magnitudes of the risks could be compared across tumor sites. Methods: Epidemiologic studies that estimated

Ariana Zeka; Rebecca Gore; David Kriebel

2003-01-01

61

Migrating Ingested Foreign Body of the Upper Aerodigestive Tract with Resultant Septic Shock  

PubMed Central

Complications due to foreign body ingestion are rare; however, if present, these can cause significant morbidity to the patient. An overlooked ingested foreign body could present as an emergency and may prove fatal. We present a case of an accidentally ingested foreign body with delayed presentation, which migrated to the neck and produced a cervical abscess presenting as septic shock. The patient required prompt stabilisation followed by surgical intervention. The patient’s vital signs returned to normal on the second post-operative day, and he was discharged the following day.

Pai, Keshav; Pillai, Suresh; Bhandarkar, Ajay; Anand, Aishwarya; Sabhahit, Harshita

2013-01-01

62

Genotoxic effects of myosmine in human lymphocytes and upper aerodigestive tract epithelial cells  

Microsoft Academic Search

Myosmine, 3-(1-pyrroline-2-yl)pyridine, is an alkaloid found in tobacco plants. Recently, it was also detected in various edibles and staple foods. Whereas other tobacco alkaloids such as nicotine and nornicotine and their nitrosation products, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N?-nitrosonornicotine (NNN), have been widely discussed, the mutagenic impact of myosmine has not been investigated in detail. In the present study, possible genotoxic effects

Norbert H. Kleinsasser; Barbara C. Wallner; Ulrich A. Harréus; Wolfgang Zwickenpflug; Elmar Richter

2003-01-01

63

Alcohol Dehydrogenase 3 Genotype as a Risk Factor for Upper Aerodigestive Tract Cancers  

Microsoft Academic Search

Setting: Primary care or referral center. Patients: The study group consisted of 141 consecu- tive patients with newly diagnosed squamous cell carci- noma of the oral cavity, oropharynx, hypopharynx, or larynx admitted for surgical treatment. The comparison group consisted of 94 inpatients without cancer from the A. C. Camargo or other Sao Paulo (Brazil) hospital and 40 healthy individuals. Intervention:

Ines Nobuko Nishimoto; Nidia A. Pinheiro; Silvia R. Rogatto; AndreLopes Carvalho; Ricardo Pereira de Moura; Otavia L. Caballero; Andrew Simpson; Luiz Paulo Kowalski

2004-01-01

64

High incidence of non-upper aerodigestive primary tumors in patients with esophageal cancer  

Cancer.gov

Table 4 Retrospective studies on the incidence of other primary tumors in patients with esophageal cancer Current study Noguchi et al.11 Poon et al.10 Matsubara et al.12 Fogel et al.7 Das et al.16 No.

65

Inventory of Research into Higher Education in Canada, 1985=Inventaire des recherches sur l'enseignement superieur au Canada, 1985.  

ERIC Educational Resources Information Center

The 1985 inventory of research into higher education in Canada provides descriptions of 328 research, innovative, and experimental projects on postsecondary education in Canada. The projects, which are entered in the language in which they were reported (English or French), are grouped under six categories: general; administration, finance and…

Houwing, J. F., Ed.; Kristjanson, A. M., Ed.

66

Inventory of Research into Higher Education in Canada = Inventaire des recherches sur l'enseignement superieur au Canada.  

ERIC Educational Resources Information Center

Information is provided in English and French on research projects concerned with postsecondary education in Canada. Approximately 250 current or recently completed projects reported by researchers in universities, community colleges, educational organizations, and government departments and agencies are described. The projects, which are entered…

Houwing, J. F., Ed.; Kristjanson, A. M., Ed.

67

Inventory of Research into Higher Education in Canada, 1983 = Inventaire des Recherches sur L'Enseignement Superieur au Canada.  

ERIC Educational Resources Information Center

Information is provided in English and French on postsecondary education research projects in Canada. About 270 current or recently completed projects reported by researchers in colleges, educational associations, and government departments are described. Information is provided on completion date, name and address of researchers, source of…

Houwing, J. F., Ed.; Kristjanson, A. M., Ed.

68

Inventory of Research into Higher Education in Canada, 1984 = Inventaire des recherches sur l'enseignement superieur au Canada, 1984.  

ERIC Educational Resources Information Center

The 1984 inventory of research into higher education in Canada is presented. Descriptions are provided of about 260 projects that deal with research and practical developments in postsecondary education, its activities and characteristics. The projects, which are entered in the language in which they were reported (English or French), are grouped…

Houwing, J. F., Ed.; Kristjanson, A. M., Ed.

69

Mass Higher Education: Some Perspectives From Experience in the United States. L'Enseignement Superieur de Masse: Quelques Perspective Ouvertes par L'Experience des Etats-Unis.  

ERIC Educational Resources Information Center

Policies for higher education are under active consideration in most countries. A major issue in such policies in the seventies will be the setting up of structures adapted to a stage of development that has either been or is at the point of being reached in most countries, that of transition to mass higher education. To discuss a number of major…

Organisation for Economic Cooperation and Development, Paris (France).

70

Local network interconnection through a satellite point-to-multipoint link. Ph.D. Thesis - Ecole Nationale Superieure des Telecommunications, 6 Jul. 1985  

NASA Technical Reports Server (NTRS)

Four architectures to implement a point to multipoint satellite link protocol for communication services offered by the Telecom 1 satellite network are presented. A safe communication service with error correction and flow control facilities is described. It is shown that a time transparent communication system combines simplicity and cost advantages.

Duarte, O. Muniz Bandeira

1986-01-01

71

Higher Education and Social Origin in France: A Statistical Study of Inequalities Since 1965 = Enseignement Superieur Et Origine Sociale En France: Etude Statistique Des Inegalites Depuis 1965  

ERIC Educational Resources Information Center

Mass education has the goal of guaranteeing the same education to all in order to moderate differences between individuals and promote a kind of "equality of opportunity." Nonetheless, it seems clear that lower-class youths do not benefit as much from their degree or university experience as do those who come from more privileged backgrounds. The…

Jaoul, Magali

2004-01-01

72

WindVOiCe, a Self-Reporting Survey: Adverse Health Effects, Industrial Wind Turbines, and the Need for Vigilance Monitoring  

ERIC Educational Resources Information Center

Industrial wind turbines have been operating in many parts of the globe. Anecdotal reports of perceived adverse health effects relating to industrial wind turbines have been published in the media and on the Internet. Based on these reports, indications were that some residents perceived they were experiencing adverse health effects. The purpose…

Krogh, Carmen M. E.; Gillis, Lorrie; Kouwen, Nicholas; Aramini, Jeff

2011-01-01

73

Rôle potentiel de la TEP-FDG pour la définition du volume tumoral macroscopique (GTV) des cancers des voies aérodigestives supérieures et du poumon  

Microsoft Academic Search

The recent progresses performed in imaging, computational and technological fields bring new opportunities to achieve high precision radiation dose delivery. However, IMRT requires a particular attention at the target delineation step to avoid inadequate dosage to TVs\\/OARs. In this context, the biological information provided by PET might advantageously complete CT-Scan to refine the target delineation in HNSCC and lung cancer.

X. Geets; J. A. Lee; P. Castadot; A. Bol; V. Grégoire

2009-01-01

74

Programs and Projects  

Cancer.gov

Programs and Projects Lung and Upper Aerodigestive Cancers Research Group Research Portfolio Search the NCI-Funded Research Portfolio for projects supported by the Lung and Upper Aerodigestive Cancer Research Group. Use the Advanced Search to choose Division

75

EDUCAFRICA, December 1986. Special Issue: Case Studies on Higher Education in Africa. Special Volume 1=EDUCAFRICA, Decembre 1986. Etudes de cas sur L'Enseignement Superieur en Afrique, Tome 1.  

ERIC Educational Resources Information Center

Case studies of the development of higher education in 17 African countries are presented. Eleven of the case studies are written in French, and six are in English. The country reports that are in English are as follows: Cameroon, Ethiopia, Lesotho, Malawi, Sierra Leone, and Tanzania. The country reports in French are: Benin, Burkina Faso,…

EDUCAFRICA, 1986

1986-01-01

76

From Higher Education To Employment. Volume II: Canada, Denmark, Spain, United States = De l'enseignement superieur a l'emploi. Volume II: Canada, Danemark, Expagne, Etats-Unis.  

ERIC Educational Resources Information Center

This volume presents reports on the flows of graduates from higher education and on their entry into working life in Canada, Denmark, Spain and the United States. Each paper is written according to detailed guidelines designed to assemble information from many sources, to reflect the state of the art, and to illustrate a variety of approaches,…

Organisation for Economic Cooperation and Development, Paris (France).

77

Les programmes revises: Amenagement forestier, interpretation theatrale. Avis a la ministre de l'Enseignement superieur et de la Science (Revised Programs: Forest Management, Theater Arts. Advisory to the Minister of Higher Education and Science).  

ERIC Educational Resources Information Center

This two-part report contains an analyses conducted by the Council of Colleges, in Quebec, of proposed revisions to programs in Forestry Management and Theater Arts offered by the province's public colleges. First, the report considers existing and proposed forestry programs in terms of their relationship to the current practices in the forestry…

Conseil des Colleges, Quebec (Quebec).

78

From Higher Education to Employment. Volume III: Finland, France, Italy, Japan, Netherlands, Norway = De l'enseignement superieur a l'emploi. Volume III: Finlande, France, Italie, Japan, Norrege, Pays-Bas.  

ERIC Educational Resources Information Center

This document presents statistical data from the countries of France, Finland, the Netherlands, Japan, Italy, and Norway regarding the flows of graduates from higher education and their entry into the workforce. Among the statistical data presented are the trends and current situation in each country for such areas as college enrollments and…

Organisation for Economic Cooperation and Development, Paris (France).

79

From Higher Education to Employment. Volume IV: Portugal, United Kingdom, Sweden, Switzerland = De l'enseignement superieur a l'emploi. Volume IV: Portugal, Royaume-Uni, Suede, Suisse.  

ERIC Educational Resources Information Center

This volume reports on the flow of graduates from higher education into working life in Portugal, the United Kingdom, Sweden and Switzerland. Chapters for each nation were contributed by national experts in that field. The first section of the report, on Portugal, contains two papers. The first, written in English, discusses recent changes in the…

Organisation for Economic Cooperation and Development, Paris (France).

80

L'E.A.P. ou l'anglais enseigne dans les etudes superieures. Un guide pour le debutant (E.A.P. or English for Academic Purposes: A Guide for the Beginner).  

ERIC Educational Resources Information Center

Addresses those readers who are not familiar with EAP, offering an introductory discussion of its objectives and methods, in two parts. Devotes the first part to the needs that justify an EAP approach, and the second to its methodology, with particular attention to interdisciplinary, task-oriented instruction. Societe Nouvelle Didier Erudition, 40…

Roe, Peter J.

1981-01-01

81

Higher Education and Economic Development in Europe, 1975-1980 (A Statistical and Economic Study) = L'enseignement superieur et le development economique en Europe, 1975-1980 (etude statistique et economique). Volume I.  

ERIC Educational Resources Information Center

Information on higher education in 33 European countries, the United States, and Canada is provided in narrative and statistical form, in both English and French. In addition to covering the 1970-1975 period, comparative information for 1960-1980 is presented. For each country, areas of consideration include: population trends; the level of…

Burloiu, Petre

82

Higher Education and Economic Development in Europe, 1975-1980: (A Statistical and Economic Study) = L'Enseignement Superieur et le Developpement Economique en Europe, 1975-1980: (Etude Statistique et Economique). Vol. II.  

ERIC Educational Resources Information Center

Statistical tables on higher education and economic development in Europe, Israel, Canada, and the United States, for 1975-1980 are presented in the second of a two-volume report. This volume of statistical tables, presented in both English and French, covers the following areas: population estimates for 33 countries for 1960, 1965, 1970, and…

Burloiu, Petre

83

Intérêt de la tomographie par émission de positons (TEP) au 18FDG dans le suivi des patients traités pour carcinome épidermoïde des voies aérodigestives supérieures (VADS) en rémission clinique  

Microsoft Academic Search

IntroductionPosttreatment follow-up of head and neck squamous cell carcinoma (HNSCC) recurrence is a diagnostic challenge. Tissue distortions from radiation and surgery can obscure early detection of recurrence by conventional follow-up approaches such as physical examination (PE), computed tomography, and magnetic resonance imaging. A number of studies have shown that 18Fluoro-fluorodeoxyglucose (18FDG) Positron emission tomography (PET) may be an effective technique

R. Abgral; S. Querellou; G. Potard; P.-Y. Le Roux; A. Le Duc-Pennec; R. Marianowski; O. Pradier; Y. Bizais; F. Kraeber-Bodéré; P.-Y. Salaün

2009-01-01

84

La Transmission de l'information dans une ecole (Information Transmission in a School Situation)  

ERIC Educational Resources Information Center

Selected portions of a longer paper entitled "Incidence relationnelle et institutionelle de la transmission de l'information dans une ecole," presented at the Institut Superieur de Pedagogie, 1973. (HW)

Versel, Simone

1973-01-01

85

Contrast-to-noise ratio improvement in volume-of-interest cone beam breast CT  

NASA Astrophysics Data System (ADS)

In this study, we demonstrated the contrast-to-noise ratio (CNR) improvement in breast cone beam CT (CBCT) using the volume-of-interest (VOI) scanning technique. In VOI breast CBCT, the breast is first scanned at a low exposure level. A pre-selected VOI is then scanned at a higher exposure level with collimated x-rays. The two image sets are combined together to reconstruct high quality 3-D images of the VOI. A flat panel detector based system was built to demonstrate and investigate the CNR improvement in VOI breast CBCT. The CNRs of the 8 plastic cones (Teflon, Delrin, polycarbonate, Lucite, solid water, high density polystyrene, nylon and polystyrene) in a breast phantom were measured in images obtained with the VOI CBCT technique and compared to those measured in standard full field CBCT images. CNRs in VOI CBCT images were found to be higher than those in regular CBCT images in all plastic cones. The mean glandular doses (MGDs) from the combination of a high exposure VOI scan and a low exposure full-field scan was estimated to be similar to that from regular full-field scan at standard exposure level. The VOI CBCT technique allows a VOI to be imaged with enhanced image quality with an MGD similar to that from regular CBCT technique.

Shen, Youtao; Liu, Xinming; Lai, Chao-Jen; Zhong, Yuncheng; Yi, Ying; You, Zhicheng; Wang, Tianpeng; Shaw, Chris C.

2012-02-01

86

Value of information literature analysis: a review of applications in health risk management.  

PubMed

This article provides the first comprehensive review of value of information (VOI) analyses related to health risk management published in English in peer-reviewed journals by the end of 2001. VOI analysis represents a decision analytic technique that explicitly evaluates the benefit of collecting additional information to reduce or eliminate uncertainty. Through a content analysis of VOI applications, this article characterizes various attributes of VOI applications, shows the evolution of the methodology and advances in computing tools that allow analysis of increasingly complex problems, and suggests the need for some standardization of reporting methods and results. The authors' analysis shows a lack of cross-fertilization across topic areas and the tendency of articles to focus on demonstrating the usefulness of the VOI approach rather than applications to actual management decisions. This article provides important insights for VOI applications in medical decision making. PMID:15155018

Yokota, Fumie; Thompson, Kimberly M

2004-01-01

87

Value of information in virtual patient performance evaluations.  

PubMed

The American Board of Family Medicine (ABFM) uses virtual patients (VP) in Maintenance of Certification. User queries might be evaluated by calculating diagnostic value of information (VOI). Typical primary care queries address concerns far beyond efficient diagnosis. We identify practical constraints on VOI scoring in simulations of primary care practice. We imagine a Bayesian physician as the ideal candidate for VOI scoring. Bayesian physicians require an explicit decision making perspective and many local data. PMID:18998811

Sumner, Walton; Hagen, Michael D

2008-01-01

88

Value of information analysis in environmental health risk management decisions: past, present, and future.  

PubMed

Experts agree that value of information (VOI) analyses provide useful insights in risk management decisions. However, applications in environmental health risk management (EHRM) remain largely demonstrative thus far because of the complexity in modeling and solving VOI problems. Based on this comprehensive review of all VOI applications published in the peer-reviewed literature of such applications, the complexity of solving VOI problems with continuous probability distributions as inputs in models emerges as the main barrier to greater use of VOI although simulation allows analysts to solve more complex and realistic problems. Several analytical challenges that inhibit greater use of VOI techniques include issues related to modeling decisions, valuing outcomes, and characterizing uncertain and variable model inputs appropriately. This comprehensive review of methods for modeling and solving VOI problems for applications related to EHRM provides the first synthesis of important methodological advances in the field. The insights provide risk analysts and decision scientists with some guidance on how to structure and solve VOI problems focused on evaluating opportunities to collect better information to improve EHRM decisions. They further suggest the need for some efforts to standardize approaches and develop some prescriptive guidance for VOI analysts similar to existing guidelines for conducting cost-effectiveness analyses. PMID:15209935

Yokota, Fumie; Thompson, Kimberly M

2004-06-01

89

High resolution dual detector volume-of-interest cone beam breast CT - Demonstration with a bench top system  

SciTech Connect

Purpose: In this study, we used a small field high resolution detector in conjunction with a full field flat panel detector to implement and investigate the dual detector volume-of-interest (VOI) cone beam breast computed tomography (CBCT) technique on a bench-top system. The potential of using this technique to image small calcifications without increasing the overall dose to the breast was demonstrated. Significant reduction of scatter components in the high resolution projection image data of the VOI was also shown. Methods: With the regular flat panel based CBCT technique, exposures were made at 80 kVp to generate an air kerma of 6 mGys at the isocenter. With the dual detector VOI CBCT technique, a high resolution small field CMOS detector was used to scan a cylindrical VOI (2.5 cm in diameter and height, 4.5 cm off-center) with collimated x-rays at four times of regular exposure level. A flat panel detector was used for full field scan with low x-ray exposures at half of the regular exposure level. The low exposure full field image data were used to fill in the truncated space in the VOI scan data and generate a complete projection image set. The Feldkamp-Davis-Kress (FDK) filtered backprojection algorithm was used to reconstruct high resolution images for the VOI. Two scanning techniques, one breast centered and the other VOI centered, were implemented and investigated. Paraffin cylinders with embedded thin aluminum (Al) wires were imaged and used in conjunction with optically stimulated luminescence (OSL) dose measurements to demonstrate the ability of this technique to image small calcifications without increasing the mean glandular dose (MGD). Results: Using exposures that produce an air kerma of 6 mGys at the isocenter, the regular CBCT technique was able to resolve the cross-sections of Al wires as thin as 254 {mu}m in diameter in the phantom. For the specific VOI studied, by increasing the exposure level by a factor of 4 for the VOI scan and reducing the exposure level by a factor of 2 for the full filed scan, the dual-detector CBCT technique was able to resolve the cross-sections of Al wires as thin as 152 {mu}m in diameter. The CNR evaluated for the entire Al wire cross-section was found to be improved from 5.5 in regular CBCT to 14.4 and 16.8 with the breast centered and VOI centered scanning techniques, respectively. Even inside VOI center, the VOI scan resulted in significant dose saving with the dose reduced by a factor of 1.6 at the VOI center. Dose saving outside the VOI was substantial with the dose reduced by a factor of 7.3 and 7.8 at the breast center for the breast centered and VOI centered scans, respectively, when compared to full field scan at the same exposure level. The differences between the two dual detector techniques in terms of dose saving and scatter reduction were small with VOI scan at 4x exposure level and full field scan at 0.5x exposure level. The MGDs were only 94% of that from the regular CBCT scan. Conclusions: For the specific VOI studied, the dual detector VOI CBCT technique has the potential to provide high quality images inside the VOI with MGD similar to or even lower than that of full field breast CBCT. It was also found that our results were compromised by the use of inadequate detectors for the VOI scan. An appropriately selected detector would better optimize the image quality improvement that can be achieved with the VOI CBCT technique.

Shen Youtao; Yi Ying; Zhong Yuncheng; Lai Chaojen; Liu Xinming; You Zhicheng; Ge Shuaiping; Wang Tianpeng; Shaw, Chris C. [Department of Imaging Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030 (United States)

2011-12-15

90

High resolution dual detector volume-of-interest cone beam breast CT--Demonstration with a bench top system  

PubMed Central

Purpose: In this study, we used a small field high resolution detector in conjunction with a full field flat panel detector to implement and investigate the dual detector volume-of-interest (VOI) cone beam breast computed tomography (CBCT) technique on a bench-top system. The potential of using this technique to image small calcifications without increasing the overall dose to the breast was demonstrated. Significant reduction of scatter components in the high resolution projection image data of the VOI was also shown. Methods: With the regular flat panel based CBCT technique, exposures were made at 80 kVp to generate an air kerma of 6 mGys at the isocenter. With the dual detector VOI CBCT technique, a high resolution small field CMOS detector was used to scan a cylindrical VOI (2.5 cm in diameter and height, 4.5 cm off-center) with collimated x-rays at four times of regular exposure level. A flat panel detector was used for full field scan with low x-ray exposures at half of the regular exposure level. The low exposure full field image data were used to fill in the truncated space in the VOI scan data and generate a complete projection image set. The Feldkamp-Davis-Kress (FDK) filtered backprojection algorithm was used to reconstruct high resolution images for the VOI. Two scanning techniques, one breast centered and the other VOI centered, were implemented and investigated. Paraffin cylinders with embedded thin aluminum (Al) wires were imaged and used in conjunction with optically stimulated luminescence (OSL) dose measurements to demonstrate the ability of this technique to image small calcifications without increasing the mean glandular dose (MGD). Results: Using exposures that produce an air kerma of 6 mGys at the isocenter, the regular CBCT technique was able to resolve the cross-sections of Al wires as thin as 254 ?m in diameter in the phantom. For the specific VOI studied, by increasing the exposure level by a factor of 4 for the VOI scan and reducing the exposure level by a factor of 2 for the full filed scan, the dual-detector CBCT technique was able to resolve the cross-sections of Al wires as thin as 152 ?m in diameter. The CNR evaluated for the entire Al wire cross-section was found to be improved from 5.5 in regular CBCT to 14.4 and 16.8 with the breast centered and VOI centered scanning techniques, respectively. Even inside VOI center, the VOI scan resulted in significant dose saving with the dose reduced by a factor of 1.6 at the VOI center. Dose saving outside the VOI was substantial with the dose reduced by a factor of 7.3 and 7.8 at the breast center for the breast centered and VOI centered scans, respectively, when compared to full field scan at the same exposure level. The differences between the two dual detector techniques in terms of dose saving and scatter reduction were small with VOI scan at 4×?exposure level and full field scan at 0.5×?exposure level. The MGDs were only 94% of that from the regular CBCT scan. Conclusions: For the specific VOI studied, the dual detector VOI CBCT technique has the potential to provide high quality images inside the VOI with MGD similar to or even lower than that of full field breast CBCT. It was also found that our results were compromised by the use of inadequate detectors for the VOI scan. An appropriately selected detector would better optimize the image quality improvement that can be achieved with the VOI CBCT technique.

Shen, Youtao; Yi, Ying; Zhong, Yuncheng; Lai, Chao-Jen; Liu, Xinming; You, Zhicheng; Ge, Shuaiping; Wang, Tianpeng; Shaw, Chris C.

2011-01-01

91

Value of information analysis in healthcare: a review of principles and applications.  

PubMed

Abstract Background: Economic evaluations are increasingly utilized to inform decisions in healthcare; however, decisions remain uncertain when they are not based on adequate evidence. Value of information (VOI) analysis has been proposed as a systematic approach to measure decision uncertainty and assess whether there is sufficient evidence to support new technologies. Scope: The objective of this paper is to review the principles and applications of VOI analysis in healthcare. Relevant databases were systematically searched to identify VOI articles. The findings from the selected articles were summarized and narratively presented. Findings: Various VOI methods have been developed and applied to inform decision-making, optimally designing research studies and setting research priorities. However, the application of this approach in healthcare remains limited due to technical and policy challenges. Conclusion: There is a need to create more awareness about VOI analysis, simplify its current methods, and align them with the needs of decision-making organizations. PMID:24650041

Tuffaha, Haitham W; Gordon, Louisa G; Scuffham, Paul A

2014-06-01

92

Dual resolution cone beam breast CT: A feasibility study  

SciTech Connect

Purpose: In this study, the authors investigated the feasibility of a dual resolution volume-of-interest (VOI) cone beam breast CT technique and compared two implementation approaches in terms of dose saving and scatter reduction. Methods: With this technique, a lead VOI mask with an opening is inserted between the x-ray source and the breast to deliver x-ray exposure to the VOI while blocking x rays outside the VOI. A CCD detector is used to collect the high resolution projection data of the VOI. Low resolution cone beam CT (CBCT) images of the entire breast, acquired with a flat panel (FP) detector, were used to calculate the projection data outside the VOI with the ray-tracing reprojection method. The Feldkamp-Davis-Kress filtered backprojection algorithm was used to reconstruct the dual resolution 3D images. Breast phantoms with 180 {mu}m and smaller microcalcifications (MCs) were imaged with both FP and FP-CCD dual resolution CBCT systems, respectively. Two approaches of implementing the dual resolution technique, breast-centered approach and VOI-centered approach, were investigated and evaluated for dose saving and scatter reduction with Monte Carlo simulation using a GEANT4 package. Results: The results showed that the breast-centered approach saved more breast absorbed dose than did VOI-centered approach with similar scatter reduction. The MCs in fatty breast phantom, which were invisible with FP CBCT scan, became visible with the FP-CCD dual resolution CBCT scan. Conclusions: These results indicate potential improvement of the image quality inside the VOI with reduced breast dose both inside and outside the VOI.

Chen Lingyun; Shen Youtao; Lai, Chao-Jen; Han Tao; Zhong Yuncheng; Ge Shuaiping; Liu Xinming; Wang Tianpeng; Yang, Wei T.; Whitman, Gary J.; Shaw, Chris C. [Department of Imaging Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030-4009 (United States); Department of Diagnostic Radiology, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030-4009 (United States); Department of Imaging Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030-4009 (United States)

2009-09-15

93

A template-based procedure for determining white matter integrity in the internal capsule early after stroke  

PubMed Central

The integrity of descending white matter pathways, measured by fractional anisotropy from DW-MRI, is a key prognostic indicator of motor recovery after stroke. Barriers to translation of fractional anisotropy measures into routine clinical practice include the time required for manually delineating volumes of interest (VOIs), and inter-examiner variability in this process. This study investigated whether registering and then editing template volumes of interest ‘as required’ would improve inter-examiner reliability compared with manual delineation, without compromising validity. MRI was performed with 30 sub-acute stroke patients with motor deficits (mean NIHSS = 11, range 0–17). Four independent examiners manually delineated VOIs for the posterior limbs of the internal capsules on T1 images, or edited template VOIs that had been registered to the T1 images if they encroached on ventricles or basal ganglia. Fractional anisotropy within each VOI and interhemispheric asymmetry were then calculated. We found that 13/30 registered template VOIs required editing. Edited template VOIs were more spatially similar between examiners than the manually delineated VOIs (p = 0.005). Both methods produced similar asymmetry values that correlated with clinical scores with near perfect levels of agreement between examiners. Contralesional fractional anisotropy correlated with age when edited template VOIs were used but not when VOIs were manually delineated. Editing template VOIs as required is reliable, increases the validity of fractional anisotropy measurements in the posterior limb of the internal capsule, and is less time-consuming compared to manual delineation. This approach could support the use of FA asymmetry measures in routine clinical practice.

Petoe, Matthew A.; Byblow, Winston D.; de Vries, Esther J.M.; Krishnamurthy, Venkatesh; Zhong, Cathy S.; Barber, P. Alan; Stinear, Cathy M.

2013-01-01

94

Enhancing accuracy of magnetic resonance image fusion by defining a volume of interest.  

PubMed

We compared the registration accuracy for corresponding anatomical landmarks in two MR images after fusing the complete volume (CV) and a defined volume of interest (VOI) of both MRI data sets. We carried out contrast-enhanced T1-weighted gradient-echo and T2-weighted fast spin-echo MRI (matrix 256 x 256) in 39 cases. The CV and a defined VOI data set were each fused using prototype software. We measured and analysed the distance between 25 anatomical landmarks in predefined areas identified at levels L(1)-L(5) corresponding to defined axial sections. Fusion technique, landmark areas and level of fusion were further processed using a feed-forward neural network to calculate the difference which can be expected based on the measurements. We identified 975 landmarks for both T1- and T2-weighted images and found a significant difference in registration accuracy ( P<0.01) for all landmarks between CV (1.6+/-1.2 mm) and VOI (0.7+/-1.0 mm). From cranial (L(1)) to caudal (L(5)), mean deviations were: L(1) CV 1.5 mm, VOI 0.5 mm; L(2) CV 1.8 mm, VOI 0.4 mm; L(3) CV 1.7 mm, VOI 0.4 mm; L(4) CV 1.6 mm, VOI 0.6 mm; and L(5) CV 1.6 mm, VOI 1.6 mm. Neural network analysis predicted a higher accuracy for VOI (0.05-0.15 mm) than for CV fusion (0.9-1.6 mm). Deviations due to magnetic susceptibility changes between air and tissue seen on gradient-echo images can decrease fusion accuracy. Our VOI fusion technique improves image fusion accuracy to <0.5 mm by excluding areas with marked susceptibility changes. PMID:12955369

Hoelper, B M; Soldner, F; Lachner, R; Behr, R

2003-11-01

95

The Acquisition of Stereochemical Knowledge by Algerian Students Intending to Teach Physical Sciences  

ERIC Educational Resources Information Center

In this work we evaluated the level of difficulty found in learning stereochemistry concepts, by students intending to teach physical sciences at the Ecole Normale Superieure (ENS) Kouba (Algeria). A paper and pencil questionnaire was administered to 170 students to evaluate: their familiarity with Newman representations; their ability of linking…

Boukhechem, Mohamed-Salah; Dumon, Alain; Zouikri, Mohamed

2011-01-01

96

The Normative Effects of Higher Education Policy in France  

ERIC Educational Resources Information Center

This student survey was a response to the French youth unrest in 2005 and 2006. It considers the degree to which French higher and secondary education institutions create social cohesion. Focusing on three distinct higher-education institutions: "L'institut d'etudes politiques de Paris" (Sciences Po), "Ecole Normale Superieure," Paris 8, and a…

Langan, Elise

2012-01-01

97

Decrire et enseigner une competence de communication: remarques sur quelques solutions de continuite. L'Enseignement de la competence de communication en langues secondes. (Describing and Teaching Communicative Competence: Some Remarks on Solutions of Continuity. The Teaching of Communicative Competence in Second Languages.) Acts of the Colloquium of the Swiss Interuniversity Commission for Applied Linguistics. CILA Bulletin.  

ERIC Educational Resources Information Center

Two projects of the Ecole Normale Superieure de Saint-Cloud (CREDIF) are described and critically analyzed in this paper: the definition of a threshold level, "Niveau-seuil," in French and a learning module, "Looking for Work," intended to teach necessary written French to migrant workers. The threshold level section is a reference document for…

Coste, Daniel

98

A Prestigious Image: Advantage or Obstacle in Attracting Candidates to French Elite Higher Education?  

ERIC Educational Resources Information Center

One hundred and twenty students successful at entering four of the most famous French "grandes ecoles" ("Ecole Normale Superieure" Ulm, Polytechnique, HEC, Sciences Po) were questioned about their institution's image. We focus on how the prestige of these institutions in the French society played a role in students' attraction and contributed to…

Draelants, Hugues

2012-01-01

99

Fluorescence Optic Fiber Stereotactic Needle Ratiometer for Breast Tumor Diagnosis.  

National Technical Information Service (NTIS)

Activities during the second year were still restricted to gaining head start knowledge of the intended instrument from the development of a similar instrument for another project. an aerodigestive cancer diagnosis clinical study at Memorial Sloan-Ketteri...

G. C. Tang

1996-01-01

100

A tricky tracheotomy: airway management dilemma following unusual stab injury to the mouth.  

PubMed

Traumatic wounding to the upper aerodigestive tract can cause acute airway compromise. In these circumstances establishment of a safe airway is vital. We present a case report illustrating the decision making pathway in such a difficult case. PMID:22524920

Mepani, V N; Antscherl, J

2012-01-01

101

A tricky tracheotomy: airway management dilemma following unusual stab injury to the mouth  

PubMed Central

Traumatic wounding to the upper aerodigestive tract can cause acute airway compromise. In these circumstances establishment of a safe airway is vital. We present a case report illustrating the decision making pathway in such a difficult case.

Mepani, VN; Antscherl, J

2012-01-01

102

Heterotopic Brain in the Pterygopalatine Fossa  

Microsoft Academic Search

Summary: Heterotopic brain outside the cranial vault is uncom- mon. It occurs most frequently in the nasal region, although rests elsewhere in the aerodigestive tract have been reported. We describe a case of heterotopic brain in the pterygopalatine fossa.

James E. Kallman; Laurie A. Loevner; David M. Yousem; Ara A. Chalian; Donald C. Lanza; Li Jin; Richard E. Hayden

103

Funding Opportunities  

Cancer.gov

Funding Opportunities Funding Related Resources DCP Funding Resources NCI Grant Application and Review Process Lung and Upper Aerodigestive Cancer Research Portfolio Search the NCI-Funded Research Portfolio for projects supported by the Division of

104

Interactive annotation of textures in thoracic CT scans  

NASA Astrophysics Data System (ADS)

This study describes a system for interactive annotation of thoracic CT scans. Lung volumes in these scans are segmented and subdivided into roughly spherical volumes of interest (VOIs) with homogeneous texture using a clustering procedure. For each 3D VOI, 72 features are calculated. The observer inspects the scan to determine which textures are present and annotates, with mouse clicks, several VOIs of each texture. Based on these annotations, a k-nearest-neighbor classifier is trained, which classifies all remaining VOIs in the scan. The algorithm then presents a slice with suggested annotations to the user, in which the user can correct mistakes. The classifier is retrained, taking into account these new annotations, and the user is presented another slice for correction. This process continues until at least 50% of all lung voxels in the scan have been classified. The remaining VOIs are classified automatically. In this way, the entire lung volume is annotated. The system has been applied to scans of patients with usual and non-specific interstitial pneumonia. The results of interactive annotation are compared to a setup in which the user annotates all predefined VOIs manually. The interactive system is 3.7 times as fast as complete manual annotation of VOIs and differences between the methods are similar to interobserver variability. This is a first step towards precise volumetric quantitation of texture patterns in thoracic CT in clinical research and in clinical practice.

Kockelkorn, Thessa T. J. P.; de Jong, Pim A.; Gietema, Hester A.; Grutters, Jan C.; Prokop, Mathias; van Ginneken, Bram

2010-03-01

105

Minimal modeling approaches to value of information analysis for health research.  

PubMed

Value of information (VOI) techniques can provide estimates of the expected benefits from clinical research studies that can inform decisions about the design and priority of those studies. Most VOI studies use decision-analytic models to characterize the uncertainty of the effects of interventions on health outcomes, but the complexity of constructing such models can pose barriers to some practical applications of VOI. However, because some clinical studies can directly characterize uncertainty in health outcomes, it may sometimes be possible to perform VOI analysis with only minimal modeling. This article 1) develops a framework to define and classify minimal modeling approaches to VOI, 2) reviews existing VOI studies that apply minimal modeling approaches, and 3) illustrates and discusses the application of the minimal modeling to 2 new clinical applications to which the approach appears well suited because clinical trials with comprehensive outcomes provide preliminary estimates of the uncertainty in outcomes. The authors conclude that minimal modeling approaches to VOI can be readily applied in some instances to estimate the expected benefits of clinical research. PMID:21712493

Meltzer, David O; Hoomans, Ties; Chung, Jeanette W; Basu, Anirban

2011-01-01

106

Scoring performance on computer-based patient simulations: beyond value of information.  

PubMed Central

As computer based clinical case simulations become increasingly popular for training and evaluating clinicians, approaches are needed to evaluate a trainee's or examinee's solution of the simulated cases. In 1997 we developed a decision analytic approach to scoring performance on computerized patient case simulations, using expected value of information (VOI) to generate a score each time the user requested clinical information from the simulation. Although this measure has many desirable characteristics, we found that the VOI was zero for the majority of information requests. We enhanced our original algorithm to measure potential decrements in expected utility that could result from using results of information requests that have zero VOI. Like the original algorithm, the new approach uses decision models, represented as influence diagrams, to represent the diagnostic problem. The process of solving computer based patient simulations involves repeated cycles of requesting and receiving these data from the simulations. Each time the user requests clinical data from the simulation, the influence diagram is evaluated to determine the expected VOI of the requested clinical datum. The VOI is non-zero only it the requested datum has the potential to change the leading diagnosis. The VOI is zero when the data item requested does not map to any node in the influence diagram or when the item maps to a node but does not change the leading diagnosis regardless of it's value. Our new algorithm generates a score for each of these situations by modeling what would happen to the expected utility of the model if the user changes the leading diagnosis based on the results. The resulting algorithm produces a non-zero score for all information requests. The score is the VOI when the VOI is non-zero It is a negative number when the VOI is zero.

Downs, S. M.; Marasigan, F.; Abraham, V.; Wildemuth, B.; Friedman, C. P.

1999-01-01

107

Scoring performance on computer-based patient simulations: beyond value of information.  

PubMed

As computer based clinical case simulations become increasingly popular for training and evaluating clinicians, approaches are needed to evaluate a trainee's or examinee's solution of the simulated cases. In 1997 we developed a decision analytic approach to scoring performance on computerized patient case simulations, using expected value of information (VOI) to generate a score each time the user requested clinical information from the simulation. Although this measure has many desirable characteristics, we found that the VOI was zero for the majority of information requests. We enhanced our original algorithm to measure potential decrements in expected utility that could result from using results of information requests that have zero VOI. Like the original algorithm, the new approach uses decision models, represented as influence diagrams, to represent the diagnostic problem. The process of solving computer based patient simulations involves repeated cycles of requesting and receiving these data from the simulations. Each time the user requests clinical data from the simulation, the influence diagram is evaluated to determine the expected VOI of the requested clinical datum. The VOI is non-zero only it the requested datum has the potential to change the leading diagnosis. The VOI is zero when the data item requested does not map to any node in the influence diagram or when the item maps to a node but does not change the leading diagnosis regardless of it's value. Our new algorithm generates a score for each of these situations by modeling what would happen to the expected utility of the model if the user changes the leading diagnosis based on the results. The resulting algorithm produces a non-zero score for all information requests. The score is the VOI when the VOI is non-zero It is a negative number when the VOI is zero. PMID:10566413

Downs, S M; Marasigan, F; Abraham, V; Wildemuth, B; Friedman, C P

1999-01-01

108

28 CFR 91.63 - Preparing an Environmental Impact Statement  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Preparing an Environmental Impact Statement 91.63 Section...GRANTS FOR CORRECTIONAL FACILITIES Environmental Impact Review Procedures for VOI/TIS Grant Program Environmental Review Procedures § 91.63...

2013-07-01

109

28 CFR 91.62 - Preparing an Environmental Assessment.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Preparing an Environmental Assessment. 91.62 Section...GRANTS FOR CORRECTIONAL FACILITIES Environmental Impact Review Procedures for VOI/TIS Grant Program Environmental Review Procedures § 91.62...

2013-07-01

110

28 CFR 91.56 - Actions that normally require the preparation of an environmental assessment.  

Code of Federal Regulations, 2013 CFR

...normally require the preparation of an environmental assessment. 91.56 Section 91...GRANTS FOR CORRECTIONAL FACILITIES Environmental Impact Review Procedures for VOI...normally require the preparation of an environmental assessment. (a) Renovation...

2013-07-01

111

Planning the efficient allocation of research funds: an adapted application of a non-parametric Bayesian value of information analysis.  

PubMed

The issue of the efficient allocation of research funds has been addressed using various quantitative methods. Bayesian value of information (VoI) analysis provides an explicit and comprehensive analytic process for the comparison of alternative sources of research. This paper presents an adapted non-parametric application of a VoI analysis of prospective trials comparing alternative adjuvant therapies for postmenopausal women with node positive early breast cancer. The results show that such trials would produce substantial net benefits, though the extent of the net benefits is clearly influenced by the assumed length of usefulness of the research. The application of the VoI methodology shows that such analyses are practical and the recent increase in the use of stochastic decision models in the economic evaluation of health care technologies facilitates further applications of VoI analyses to inform the allocation of research funds. PMID:12098524

Karnon, Jonathan

2002-09-01

112

Effects of rigid and non-rigid image registration on test-retest variability of quantitative [18F]FDG PET/CT studies  

PubMed Central

Background [18F]fluoro-2-deoxy-D-glucose ([18F]FDG) positron emission tomography (PET) is a valuable tool for monitoring response to therapy in oncology. In longitudinal studies, however, patients are not scanned in exactly the same position. Rigid and non-rigid image registration can be applied in order to reuse baseline volumes of interest (VOI) on consecutive studies of the same patient. The purpose of this study was to investigate the impact of various image registration strategies on standardized uptake value (SUV) and metabolic volume test-retest variability (TRT). Methods Test-retest whole-body [18F]FDG PET/CT scans were collected retrospectively for 11 subjects with advanced gastrointestinal malignancies (colorectal carcinoma). Rigid and non-rigid image registration techniques with various degrees of locality were applied to PET, CT, and non-attenuation corrected PET (NAC) data. VOI were drawn independently on both test and retest scans. VOI drawn on test scans were projected onto retest scans and the overlap between projected VOI and manually drawn retest VOI was quantified using the Dice similarity coefficient (DSC). In addition, absolute (unsigned) differences in TRT of SUVmax, SUVmean, metabolic volume and total lesion glycolysis (TLG) were calculated in on one hand the test VOI and on the other hand the retest VOI and projected VOI. Reference values were obtained by delineating VOIs on both scans separately. Results Non-rigid PET registration showed the best performance (median DSC: 0.82, other methods: 0.71-0.81). Compared with the reference, none of the registration types showed significant absolute differences in TRT of SUVmax, SUVmean and TLG (p > 0.05). Only for absolute TRT of metabolic volume, significant lower values (p < 0.05) were observed for all registration strategies when compared to delineating VOIs separately, except for non-rigid PET registrations (p = 0.1). Non-rigid PET registration provided good volume TRT (7.7%) that was smaller than the reference (16%). Conclusion In particular, non-rigid PET image registration showed good performance similar to delineating VOI on both scans separately, and with smaller TRT in metabolic volume estimates.

2012-01-01

113

The value of value of information: best informing research design and prioritization using current methods.  

PubMed

Value of information (VOI) methods have been proposed as a systematic approach to inform optimal research design and prioritization. Four related questions arise that VOI methods could address. (i) Is further research for a health technology assessment (HTA) potentially worthwhile? (ii) Is the cost of a given research design less than its expected value? (iii) What is the optimal research design for an HTA? (iv) How can research funding be best prioritized across alternative HTAs? Following Occam's razor, we consider the usefulness of VOI methods in informing questions 1-4 relative to their simplicity of use. Expected value of perfect information (EVPI) with current information, while simple to calculate, is shown to provide neither a necessary nor a sufficient condition to address question 1, given that what EVPI needs to exceed varies with the cost of research design, which can vary from very large down to negligible. Hence, for any given HTA, EVPI does not discriminate, as it can be large and further research not worthwhile or small and further research worthwhile. In contrast, each of questions 1-4 are shown to be fully addressed (necessary and sufficient) where VOI methods are applied to maximize expected value of sample information (EVSI) minus expected costs across designs. In comparing complexity in use of VOI methods, applying the central limit theorem (CLT) simplifies analysis to enable easy estimation of EVSI and optimal overall research design, and has been shown to outperform bootstrapping, particularly with small samples. Consequently, VOI methods applying the CLT to inform optimal overall research design satisfy Occam's razor in both improving decision making and reducing complexity. Furthermore, they enable consideration of relevant decision contexts, including option value and opportunity cost of delay, time, imperfect implementation and optimal design across jurisdictions. More complex VOI methods such as bootstrapping of the expected value of partial EVPI may have potential value in refining overall research design. However, Occam's razor must be seriously considered in application of these VOI methods, given their increased complexity and current limitations in informing decision making, with restriction to EVPI rather than EVSI and not allowing for important decision-making contexts. Initial use of CLT methods to focus these more complex partial VOI methods towards where they may be useful in refining optimal overall trial design is suggested. Integrating CLT methods with such partial VOI methods to allow estimation of partial EVSI is suggested in future research to add value to the current VOI toolkit. PMID:20629473

Eckermann, Simon; Karnon, Jon; Willan, Andrew R

2010-01-01

114

Exact Interior Reconstruction with Cone-Beam CT  

Microsoft Academic Search

Using the backprojection filtration (BPF) and filtered backprojection (FBP) approaches respectively, we prove that with cone-beam CT the interior problem can be exactly solved by analytic continuation. The prior knowledge we assume is that a volume of interest (VOI) in an object to be reconstructed is known in a sub-region of the VOI. Our derivations are based on the so-called

Yangbo Ye; Hengyong Yu; Ge Wang

2007-01-01

115

Computer-aided detection of lung nodules based on decision fusion techniques  

Microsoft Academic Search

We adopted decision fusion techniques to develop a computer-aided detection (CAD) system for automatic detection of pulmonary\\u000a nodules in low-dose CT images. Two distinct phases, aimed, respectively, at detecting volumes of interests (VOIs) within the\\u000a CT scan, and at classifying VOIs into nodules and non-nodules, were considered. Three algorithms, namely thresholding, region\\u000a growing and robust fuzzy clustering, were used as

Michela Antonelli; Marco Cococcioni; Beatrice Lazzerini; Francesco Marcelloni

2011-01-01

116

Value of information in virtual patients portraying pharyngitis.  

PubMed

The American Board of Family Medicine (ABFM) uses virtual patients (VP) in Maintenance of Certification. Theoretically, the ABFM could score users on the value of information (VOI) in their queries. Pharyngitis, a prototypical primary care topic, appears practically intractable to VOI scoring. Problems include conflicting goals of various stakeholders and strong regional and temporal variability in disease characteristics. Nevertheless, the analysis yielded insights that may shift, or validate, the ABFM's selection of scoring criteria. PMID:18998813

Sumner, Walton; Hagen, Michael D

2008-01-01

117

Standardized three-dimensional volumes of interest with adapted surfaces for more precise subchondral bone analyses by micro-computed tomography.  

PubMed

Micro-computed tomography can be used to analyze subchondral bone features below treated cartilage defects in animal models. However, standardized methods for generating precise three-dimensional (3D) volumes of interest (VOI) below curved articular surfaces are lacking. The aims of this study were to develop standardized 3D VOI models adapted to the curved articular surface, and to characterize the subchondral bone specifically below a cartilage defect zone in intact and defect femoral trochlea. Skeletally mature rabbit distal femurs (N?=?8 intact; N?=?6 with acute debrided and microdrilled trochlear defects) were scanned by micro-computed tomography. Bone below the defect zone (3.5 mm width, 3.6 mm length, 1 mm deep) was quantified using simple geometric rectangular VOIs, and an optimized 3D VOI model with an adapted surface curvature, the Rectangle with Adapted Surface (RAS) model. In addition, a 250-?m-thick Curved-RAS model analyzed bone at three discrete subchondral levels. Simple geometric VOIs failed to analyze ~17% of the tissue volume, mainly near the top of the curved trochlear ridges. The RAS models revealed that after debridement and drilling, only 31% of the original bone remained within the VOI and bone loss was mainly accounted for by surgical debridement. Adapted surface VOIs are better than simple geometric VOI shapes for quantifying structural features of subchondral bone below a curved articular surface. Structural differences between the bone plate and cancellous bone were best captured using the smaller, depth-dependent Curved-RAS model. PMID:21142419

Marchand, Catherine; Chen, Hongmei; Buschmann, Michael D; Hoemann, Caroline D

2011-04-01

118

Enhancing accuracy of magnetic resonance image fusion by defining a volume of interest  

Microsoft Academic Search

We compared the registration accuracy for corresponding anatomical landmarks in two MR images after fusing the complete volume (CV) and a defined volume of interest (VOI) of both MRI data sets. We carried out contrast-enhanced T1-weighted gradient-echo and T2-weighted fast spin-echo MRI (matrix 256×256) in 39 cases. The CV and a defined VOI data set were each fused using prototype software.

B. M. Hoelper; F. Soldner; R. Lachner; R. Behr

2003-01-01

119

Gaussian process models of dynamic PET for functional volume definition in radiation oncology.  

PubMed

In routine oncologic positron emission tomography (PET), dynamic information is discarded by time-averaging the signal to produce static images of the "standardised uptake value" (SUV). Defining functional volumes of interest (VOIs) in terms of SUV is flawed, as values are affected by confounding factors and the chosen time window, and SUV images are not sensitive to functional heterogeneity of pathological tissues. Also, SUV iso-contours are highly affected by the choice of threshold and no threshold, or other SUV-based segmentation method, is universally accepted for a given VOI type. Gaussian Process (GP) time series models describe macro-scale dynamic behavior arising from countless interacting micro-scale processes, as is the case for PET signals from heterogeneous tissue. We use GPs to model time-activity curves (TACs) from dynamic PET and to define functional volumes for PET oncology. Probabilistic methods of tissue discrimination are presented along with novel contouring methods for functional VOI segmentation. We demonstrate the value of GP models for voxel classification and VOI contouring of diseased and metastatic tissues with functional heterogeneity in prostate PET. Classification experiments reveal superior sensitivity and specificity over SUV calculation and a TAC-based method proposed in recent literature. Contouring experiments reveal differences in shape between gold-standard and GP VOIs and correlation with kinetic models shows that the novel VOIs contain extra clinically relevant information compared to SUVs alone. We conclude that the proposed models offer a principled data analysis technique that improves on SUVs for oncologic VOI definition. Continuing research will generalize GP models for different oncology tracers and imaging protocols with the ultimate goal of clinical use including treatment planning. PMID:22498690

Shepherd, Tony; Owenius, Rikard

2012-08-01

120

Completeness map evaluation demonstrated with candidate next-generation cardiac CT architectures  

PubMed Central

Purpose: In this report, the authors introduce the general concept of the completeness map, as a means to evaluate the completeness of data acquired by a given CT system design (architecture and scan mode). They illustrate the utility of completeness map by applying the completeness map concept to a number of candidate CT system designs, as part of a study to advance the state-of-the-art in cardiac CT. Methods: In order to optimally reconstruct a point within a volume of interest (VOI), the Radon transform on all possible planes through that point should be measured. The authors quantified the extent to which this ideal condition is satisfied for the entire image volume. They first determined a Radon completeness number for each point in the VOI, as the percentage of possible planes that is actually measured. A completeness map is then defined as a 3D matrix of the completeness numbers for the entire VOI. The authors proposed algorithms to analyze the projection datasets in Radon space and compute the completeness number for a fixed point and apply these algorithms to various architectures and scan modes that they are evaluating. In this report, the authors consider four selected candidate architectures, operating with different scan modes, for a total of five system design alternatives. Each of these alternatives is evaluated using completeness map. Results: If the detector size and cone angle are large enough to cover the entire cardiac VOI, a single-source circular scan can have ?99% completeness over the entire VOI. However, only the central z-slice can be exactly reconstructed, which corresponds to 100% completeness. For a typical single-source architecture, if the detector is limited to an axial dimension of 40 mm, a helical scan needs about five rotations to form an exact reconstruction region covering the cardiac VOI, while a triple-source helical scan only requires two rotations, leading to a 2.5x improvement in temporal resolution. If the source and detector of an inverse-geometry (IGCT) system have the same axial extent, and the spacing of source points in the axial and transaxial directions is sufficiently small, the IGCT can also form an exact reconstruction region for the cardiac VOI. If the VOI can be covered by the x-ray beam in any view, a composite-circling scan can generate an exact reconstruction region covering the VOI. Conclusions: The completeness map evaluation provides useful information for selecting the next-generation cardiac CT system design. The proposed completeness map method provides a practical tool for analyzing complex scanning trajectories, where the theoretical image quality for some complex system designs is impossible to predict, without yet-undeveloped reconstruction algorithms.

Liu, Baodong; Bennett, James; Wang, Ge; De Man, Bruno; Zeng, Kai; Yin, Zhye; Fitzgerald, Paul; Yu, Hengyong

2012-01-01

121

A comparison of spatially resolved spectroscopy and stimulated echo acquisition mode sequences for volume-localized spectroscopy  

NASA Astrophysics Data System (ADS)

Studies have been performed to compare the spatially resolved spectroscopy (SPARS) sequence and the stimulated echo acquisition mode (STEAM) sequence. Slice profile and imaging studies were performed using phantoms to compare the quality of localization with the two sequences when the volume of interest (VOI) was moved away from the magnet isocenter. Experiments were also performed to compare the spectral quality obtained with the two sequences, especially when the VOI was moved away from the magnet isocenter. These studies indicate that the definition of the VOI, signal-to-noise ratio, and spectral resolution obtained with STEAM were comparable at different spatial locations within the sample. This, however, was not true when using SPARS due to the phase shifts induced by the spatially dependent gradient settling times. Furthermore, these studies indicate that the spectral quality obtained with SPARS was compromised due to off resonance effects when the pulse lengths of the hard pulses were long.

Jackson, E. F.; Narayana, P. A.; Kudrle, W. A.

122

Volume-of-interest imaging of the inner ear in a human temporal bone specimen using a robot- driven C-arm flat panel detector CT system.  

PubMed

VOI imaging can provide higher image quality at a reduced dose for a subregion. In this study with a robot-driven C-arm FDCT system, the goals were proof of feasibility for inner ear imaging, higher flexibility during data acquisition, and easier processing during reconstruction. First a low-dose OV scan was acquired allowing an orientation and enabling the selection of the VOI. The C-arm was then moved by the robotic system without a need for patient movement and the VOI was scanned with adapted parameters. Uncompromised artifact-free image quality was achieved by the 2-scan approach and the dose was reduced by 80%-90% in comparison with conventional MSCT and FPCT scans. PMID:21835947

Kolditz, D; Struffert, T; Kyriakou, Y; Bozzato, A; Dörfler, A; Kalender, W A

2012-11-01

123

Organ Site-Specific SPOREs | Translational Research Program (TRP)  

Cancer.gov

Skip to Content Search this site Organ Site-Specific SPOREs By State By Organ Location Last Updated: 11/28/13 Thyroid SPOREs SPOREs in Head and Neck (H&N) cancer support translational research on cancers of the upper aero-digestive tract and on thyroid

124

Dietary Zinc Modulation of COX2 Expression and Lingual and Esophageal Carcinogenesis in Rats  

Microsoft Academic Search

Background: Cancer of the upper aerodigestive tract, includ- ing esophageal and tongue carcinomas, is a major cause of cancer deaths worldwide. Esophageal and tongue cancers have both been associated with dietary zinc deficiency (ZD), and cyclooxygenase (COX-2) is often overexpressed in these cancers. Using rat models, we examined whether zinc regu- lates COX-2 expression in these cancers. Method: Expression of

Louise Y. Y. Fong; Liang Zhang; Yubao Jiang; John L. Farber

2005-01-01

125

Epidemiology of head and neck cancer: Magnitude of the problem  

Microsoft Academic Search

Head and neck cancer comprises squamous cell carcinomas of the upper aerodigestive tract. There are similarities in their natural history, epidemiology and control. For these cancers premalignant changes can be identified. Smoking and drinking are the major risk factors. The geographical variations in incidence and mortality are indicative of differences in the prevalence of risk factors between countries. The dramatic

Lajos Döbróssy

2005-01-01

126

Genomic Alterations in Blastic Natural Killer\\/Extranodal Natural Killer-Like T Cell Lymphoma with Cutaneous Involvement  

Microsoft Academic Search

Natural killer and natural killer-like T cell lymphomas represent a rare type of non-Hodgkin's lymphoma originally described to involve the upper aerodigestive tract. This malignancy has been increasingly observed in other extranodal sites, particularly in the skin. Patients with cutaneous natural killer cell lymphoma generally have a poor prognosis; however, the etiology and the underlying molecular pathogenesis remain unclear. This

Xin Mao; Zerrin Onadim; Elizabeth A Price; Fiona Child; Debra M Lillington; Robin Russell-Jones; Bryan D Young; Sean Whittaker

2003-01-01

127

Effect of occlusion of a tracheotomy tube on aspiration  

Microsoft Academic Search

The purpose of the present study was to investigate the effect of occlusion of a tracheotomy tube on aspiration utilizing fluoroscopy. Twenty consecutive tracheotomized patients referred for a modified barium swallow were included. Selection criteria were ability to tolerate tracheotomy tube occlusion during the modified barium swallow procedure, no surgery of the upper aerodigestive tract except tracheotomy, and no history

Steven B. Leder; John M. Tarro; Morton I. Burrell

1996-01-01

128

Postcricoid Hemangioma: An Overlooked Cause of Dysphagia in Infants?–A Case Report  

Microsoft Academic Search

Feeding and swallowing disorders in children remain a major challenge owing to a wide differential diagnosis. Hemangioma of the upper aerodigestive tract represents one of the numerous non-neoplastic causes of dysphagia. We report two cases of postcricoid hemangioma causing inhalation and recurrent respiratory infections, treated successfully with systemic corticotherapy alone. To our knowledge, these are the second and third cases

Gauthier R. R. Desuter; Kamal El Makhloufi; Geneviève J. François; Veronique M. Godding; Christine Saint-Martin; Jean-Paul Buts; M. F. A. Hamoir

2004-01-01

129

Feeding & Motor Functioning: Start at the Hips to Get to the Lips  

ERIC Educational Resources Information Center

Swallowing is one of the most complex movement patterns that people must use accurately throughout the day and night from the time they are born. These movement patterns are very closely integrated with breathing and movement of food through the aerodigestive tract. Malalignment or dysfunction in any part of these integrated patterns and systems…

Donato, Jessica; Fox, Cathy; Mormon, Johnnie; Mormon, Mike

2008-01-01

130

Bazex Syndrome*  

PubMed Central

Acrokeratosis Paraneoplastica or Bazex syndrome is a dermatologic manifestation usually associated with the diagnosis of squamous cell carcinoma of the upper aerodigestive tract. We report a case with exuberant clinical manifestations, exemplifying the typical cutaneous lesions in this rare syndrome, in a patient with squamous cell carcinoma of the esophagus.

Rodrigues Junior, Ismael Alves; Gresta, Leticia Trivellato; Cruz, Rafaela Carolina; Carvalho, Giselly Gomes; Moreira, Melissa Heringer Chamon Barros Quintao

2013-01-01

131

Bazex syndrome.  

PubMed

Acrokeratosis Paraneoplastica or Bazex syndrome is a dermatologic manifestation usually associated with the diagnosis of squamous cell carcinoma of the upper aerodigestive tract. We report a case with exuberant clinical manifestations, exemplifying the typical cutaneous lesions in this rare syndrome, in a patient with squamous cell carcinoma of the esophagus. PMID:24346922

Rodrigues, Ismael Alves; Gresta, Letícia Trivellato; Cruz, Rafaela Carolina; Carvalho, Giselly Gomes; Moreira, Melissa Heringer Chamon Barros Quintão

2013-01-01

132

Caustic ingestion in adults: The role of endoscopic classification in predicting outcome  

Microsoft Academic Search

BACKGROUND: The ingestion of caustic substances induces an extensive spectrum of injuries to the aerodigestive tract which include extensive necrosis and perforation of the esophagus and stomach. The gold standard of safely assessing depth, extent of injury, and appropriate therapeutic regimen is esophagogastroduodenoscopy (EGD). The objective of this study was to report our clinical experience and to evaluate the role

Hao-Tsai Cheng; Chi-Liang Cheng; Cheng-Hui Lin; Jui-Hsiang Tang; Yin-Yi Chu; Nai-Jen Liu; Pang-Chi Chen

2008-01-01

133

Teleconsultation in otolaryngology: Live versus store and forward consultations  

Microsoft Academic Search

Objective: To evaluate the relative strengths and weaknesses of interactive and delayed teleconsultations in otolaryngology. Setting: Ambulatory clinic at an urban tertiary care facility. Subjects: Forty-five adult patients with known or suspected upper aerodigestive tract pathology. Intervention: Patients were interviewed by an otolaryngology chief resident (CR) using a standardized protocol; the results were presented to a board-certified otolaryngologist present locally

ANTHONY P. SCLAFANI; CONOR HENEGHAN; JEFFREY GINSBURG; PAUL SABINI; JORDAN STERN; JAY N. DOLITSKY

1999-01-01

134

Bone marrow transplantation for infantile ceramidase deficiency (Farber disease)  

Microsoft Academic Search

Infantile ceramidase deficiency (Farber disease) is an uncommon, progressive lysosomal storage disease characterized by multiple ceramide-containing nodules (lipogranulomata) in the subcutaneous tissue and upper aerodigestive tract, painful periarticular swelling, psychomotor retardation, and varying degrees of ocular, pulmonary or hepatic involvement. Management of Farber disease has been limited to symptomatic supportive care, and few affected infants survive beyond 5 years of

AM Yeager; K Armfield Uhas; CD Coles; PC Davis; WL Krause; HW Moser

2000-01-01

135

AZ ALKOHOLIZMUS BELGYÓGYÁSZATI VONATKOZÁSAI  

Microsoft Academic Search

It has long been known that alcohol consump- tion is responsible for increased illness and death. The majority of the literature suggests that alcohol in moderation is beneficial on the cardiovascular system, and excess is detri- mental to overall health. The deleterious ef- fects of heavy alcohol consumption on health are numerous: aerodigestive and breast cancers, haemorrhagic stroke, cardio-myopathy, hyper-

Morvai Veronika

136

Recurrent Respiratory Papillomatosis: A Rare Chronic Disease, Difficult to Treat, with Potential to Lung Cancer Transformation: Apropos of Two Cases and a Brief Literature Review  

Microsoft Academic Search

Recurrent respiratory papillomatosis (RRP), which is caused exclusively by human papilloma virus (HPV), is a rare condition characterized by recurrent growth of benign papillomata in the respiratory tract. The papillomata can occur anywhere in the aerodigestive tract but most frequently in the larynx, affecting both children and adults. The management of this entity remains still challenging since no specific definitive

Stamatis Katsenos; Heinrich D. Becker

2011-01-01

137

Molecular Biologic Characteristics of Seven New Cell Lines of Squamous Cell Carcinomas of the Head and Neck and Comparison to Fresh Tumor Tissue  

Microsoft Academic Search

Background: Squamous cell carcinoma (SCC) is the most frequent malignant tumor of the upper aerodigestive tract. Cell lines of these tumors facilitate the investigation of various tumor biological parameters. This study was conducted to compare molecular biologic characteristics between cell lines and fresh tumor tissue. Methods: In seven SCC-derived cell lines, cytokeratin 5\\/6 and cytokeratin 19 expression, DNA content, chromosome

Hans-J. Welkoborsky; Roland Jacob; Seyed H. Riazimand; Hubert S. Bernauer; Wolf J. Mann

2003-01-01

138

Effects of topical oral antiseptic rinses on bacterial counts of saliva in healthy human subjects  

Microsoft Academic Search

Wound infections remain a significant source of morbidity in patients undergoing major head and neck operations that invade the aerodigestive tract. Infection rates have been significantly reduced by the administration of perioperative intravenous antibiotics; however, the incidence of infection remains unacceptably high. This study was undertaken to help identify an oral antiseptic that could significantly reduce the bacterial colony count

LUIS BALBUENA; KWEON I. STAMBAUGH; SYLVESTER G. RAMIREZ; CURTIS YEAGER

1998-01-01

139

Diet and cancers of the larynx and hypopharynx: the IARC multi-center study in southwestern Europe  

Microsoft Academic Search

The main causes of cancer of the larynx and hypopharynx are smoking cigarettes and drinking alcohol. However, for these as well as for other cancers of the upper aerodigestive tract, some dietary components, mainly low consumption of fruit and vegetables, have been observed to be associated with increased cancer risk. We report results from a multicenter case-control study carried out

Jacques Estève; Elio Riboli; Georges Péquignot; Benedetto Terracini; Franco Merletti; Paolo Crosignani; Nieyes Ascunce; Lourdes Zubiri; Francois Blanchet; Luc Raymond; Francesca Repetto; Albert J. Tuyns

1996-01-01

140

Improved Regional Activity Quantitation in Nuclear Medicine using a New Approach to Correct for Tissue Partial Volume and Spillover Effects  

PubMed Central

We have developed a new method of compensating for effects of partial volume and spillover in dual-modality imaging. The approach requires segmentation of just a few tissue types within a small VOI surrounding a lesion; the algorithm estimates simultaneously, from projection data, the activity concentration within each segmented tissue inside the VOI. Measured emission projections were fitted to the sum of resolution-blurred projections of each such tissue, scaled by its unknown activity concentration, plus a global background contribution obtained by reprojection through the reconstructed image volume outside the VOI. The method was evaluated using multiple-pinhole ?SPECT data simulated for the MOBY mouse phantom containing two spherical lung tumors and one liver tumor, as well as using multiple-bead phantom data acquired on ?SPECT and ?CT scanners. Each VOI in the simulation study was 4.8 mm (12 voxels) cubed and, depending on location, contained up to four tissues (tumor, liver, heart, lung) with different values of relative 99mTc concentration. All tumor activity estimates achieved <3% bias after ~15 OSEM iterations (× 10 subsets), with better than 8% precision (?25% greater than the Cramer-Rao lower bound). The projection-based fitting approach also outperformed three SUV-like metrics, one of which was corrected for count spillover. In the bead phantom experiment, the mean ± standard deviation of the bias of VOI estimates of bead concentration were 0.9 ± 9.5%, comparable to those of a perturbation geometric transfer matrix (pGTM) approach (-5.4 ± 8.6%); however, VOI estimates were more stable with increasing iteration number than pGTM estimates, even in the presence of substantial axial misalignment between ?CT and ?SPECT image volumes.

Moore, Stephen C.; Southekal, Sudeepti; Park, Mi-Ae; McQuaid, Sarah J.; Kijewski, Marie Foley; Muller, Stefan P.

2013-01-01

141

The power of neuroimaging biomarkers for screening frontotemporal dementia.  

PubMed

Frontotemporal dementia (FTD) is a clinically and pathologically heterogeneous neurodegenerative disease that can result from either frontotemporal lobar degeneration (FTLD) or Alzheimer's disease (AD) pathology. It is critical to establish statistically powerful biomarkers that can achieve substantial cost-savings and increase the feasibility of clinical trials. We assessed three broad categories of neuroimaging methods to screen underlying FTLD and AD pathology in a clinical FTD series: global measures (e.g., ventricular volume), anatomical volumes of interest (VOIs) (e.g., hippocampus) using a standard atlas, and data-driven VOIs using Eigenanatomy. We evaluated clinical FTD patients (N?=?93) with cerebrospinal fluid, gray matter (GM) magnetic resonance imaging (MRI), and diffusion tensor imaging (DTI) to assess whether they had underlying FTLD or AD pathology. Linear regression was performed to identify the optimal VOIs for each method in a training dataset and then we evaluated classification sensitivity and specificity in an independent test cohort. Power was evaluated by calculating minimum sample sizes required in the test classification analyses for each model. The data-driven VOI analysis using a multimodal combination of GM MRI and DTI achieved the greatest classification accuracy (89% sensitive and 89% specific) and required a lower minimum sample size (N?=?26) relative to anatomical VOI and global measures. We conclude that a data-driven VOI approach using Eigenanatomy provides more accurate classification, benefits from increased statistical power in unseen datasets, and therefore provides a robust method for screening underlying pathology in FTD patients for entry into clinical trials. Hum Brain Mapp 35:4827-4840, 2014. © 2014 Wiley Periodicals, Inc. PMID:24687814

McMillan, Corey T; Avants, Brian B; Cook, Philip; Ungar, Lyle; Trojanowski, John Q; Grossman, Murray

2014-09-01

142

Pulmonary airways tree segmentation from CT examinations using adaptive volume of interest  

NASA Astrophysics Data System (ADS)

Airways tree segmentation is an important step in quantitatively assessing the severity of and changes in several lung diseases such as chronic obstructive pulmonary disease (COPD), asthma, and cystic fibrosis. It can also be used in guiding bronchoscopy. The purpose of this study is to develop an automated scheme for segmenting the airways tree structure depicted on chest CT examinations. After lung volume segmentation, the scheme defines the first cylinder-like volume of interest (VOI) using a series of images depicting the trachea. The scheme then iteratively defines and adds subsequent VOIs using a region growing algorithm combined with adaptively determined thresholds in order to trace possible sections of airways located inside the combined VOI in question. The airway tree segmentation process is automatically terminated after the scheme assesses all defined VOIs in the iteratively assembled VOI list. In this preliminary study, ten CT examinations with 1.25mm section thickness and two different CT image reconstruction kernels ("bone" and "standard") were selected and used to test the proposed airways tree segmentation scheme. The experiment results showed that (1) adopting this approach affectively prevented the scheme from infiltrating into the parenchyma, (2) the proposed method reasonably accurately segmented the airways trees with lower false positive identification rate as compared with other previously reported schemes that are based on 2-D image segmentation and data analyses, and (3) the proposed adaptive, iterative threshold selection method for the region growing step in each identified VOI enables the scheme to segment the airways trees reliably to the 4th generation in this limited dataset with successful segmentation up to the 5th generation in a fraction of the airways tree branches.

Park, Sang Cheol; Kim, Won Pil; Zheng, Bin; Leader, Joseph K.; Pu, Jiantao; Tan, Jun; Gur, David

2009-02-01

143

The value of animal test information in environmental control decisions  

Microsoft Academic Search

Value of information (VOI) analytic techniques are used to evaluate the benefit of performing animal bioassays to provide information about the cancer potency of specific chemical compounds. These tools allow the identification of the conditions in which the cost of reducing uncertainty about potency, by performing a subchronic or chronic bioassay, is justified by the benefit of having improved information

Alison C. Taylor; John S. Evans; Thomas E. McKone

1993-01-01

144

Yliopistot sattuman lähteinä ja tarttumapintoina Universiteten som källa och kontaktyta för slumpen  

Microsoft Academic Search

Kaupunkiseutujen taloudellisen menestyksen merkkejä etsitään usein tutkimus- ja kehittä- mistoiminnan määrästä, proaktiivisesta inno- vaatiopolitiikasta, riskisijoittajista, yrittäjyy- destä, luovasta luokasta ja niin edelleen. Ta- vaksi on tullut korostaa myös yliopistojen mer- kitystä. Yliopistojen rooli ei läheskään aina ole niin suora kuin toivotaan. Ne eivät välttämättä aina ole uuden yrittäjyyden ja keksintöjen kehtoja. Tästä huolimatta yliopistoilla voi olla merkittävä vaikutus taloudellises- sa

Markku Sotarauta; Richard Lester

145

DE SECUNDA VIA VAN S. THOMAS (I, q. 2, a. 3)  

Microsoft Academic Search

Nous avons essayé d'apporter quelques éclaircissements à la seconde voie des fameuses quinqué viae de la Somme Théologique de S. Thomas. La simple lecture de cette preuve de l'existence de Dieu -comme celle des autres voies d'ailleurs - nous place devant plusieurs problèmes. En premier lieu, nous nous posons inévitablement la question : quel est cet ordre de causes efficientes

G. SCHELTENS

1963-01-01

146

A Wrench fault system and nappe emplacement in Southern Kenya and Northern Tanzania.- A key area for Pan-African continental collision in East Africa?  

Microsoft Academic Search

In the Voi Area of Southern Kenya, the granulite facies rocks of the Taita Hills and the Tsavo East National Park (Galana River) can be divided into three structural domains: The Galana-East unit consists of an intercalation of flat lying metapelites and marbles of continental margin origin. These metasediments can be traced further east to the Umba Steppe (Between Mombasa

A. Bauernhofer; E. Wallbrecher; C. Hauzenberger; H. Fritz; J. Loizenbauer; G. Hoinkes; S. Muhongo; E. Mathu

2003-01-01

147

Effective 3D object detection and regression using probabilistic segmentation features in CT images  

Microsoft Academic Search

D object detection and importance regression\\/ranking are at the core for semantically interpreting 3D medical im- ages of computer aided diagnosis (CAD). In this paper, we propose effective image segmentation features and a novel multiple instance regression method for solving the above challenges. We perform supervised learning based seg- mentation algorithm on numerous lesion candidates (as 3D VOIs: Volumes Of

Le Lu; Jinbo Bi; Matthias Wolf; Marcos Salganicoff

2011-01-01

148

Rariteettikomitean hyväksymät vuoden 2004 harvinaisuushavainnot Rare birds in Finland in 2004  

Microsoft Academic Search

saan. Silti katsaukset ovat olleet varsin kat- tavia, josta kiitos kuuluu ennen muuta ha- vainnoijille ja alueellisille komiteoille. Yksittäisten lomakkeiden käsittelyaika voi kuitenkin olla nopearytmiseen toimin- taan tottuneelle nykyihmiselle pitkän tun- tuinen. RK tekee päätöksiä vain kokouk- sissaan. Maaliskuisen kevätkokouksen jäl- keen seuraava on viime vuosina pidetty elo-syyskuussa, mistä seuraa väistämättä noin puolen vuoden käsittelyaika maalis- kuussa jätettyyn ilmoitukseen. Rutiinilo-

Heikki Luoto; Tapio Aalto; Antero Lindholm; Jyrki Normaja; Visa Rauste

149

A Framework for Automated Tumor Detection in Thoracic FDG PET Images Using Texture-Based Features  

Microsoft Academic Search

This paper proposes a novel framework for tumor detection in Positron Emission Tomography (PET) images. A set of 8 second-order texture features obtained from the gray level co-occurrence matrix (GLCM) across 26 offsets, together with uptake value was used to construct a feature vector at each voxel in the data. Volume of Interest (VOI) samples from 42 images (7 patients

Vijaya Saradhi Gannavaram; Girish Gopalakrishnan; Arunabha Roy; Rakesh Mullick; Ravi Manjeshwar; Kris Thielemans; Uday Patil

2009-01-01

150

ENERGETICS OF COCKROACH LOCOMOTION  

Microsoft Academic Search

SUMMARY Cockroaches, Gromphadorhina portentosa, were run at different speeds for 20 min on a miniature treadmill enclosed in a lucite respirometer while oxygen consumption (J£),) was continuously monitored. The data collected on these 5 g insects are remarkably similar to those obtained on vertebrates. VOi rises rapidly with the onset of exercise; the ti on-response was about 1 min with

CLYDE F. HERREID; ROBERT J. FULL; DAVID A. PRAWEL

1981-01-01

151

Assessing the Value of Information of Geophysical Data For Groundwater Management  

NASA Astrophysics Data System (ADS)

Effective groundwater management requires hydrogeologic models informed by various data sources. The long-term goal of our research is to develop methodologies that quantify the value of information (VOI) of geophysical data for water managers. We present an initial sensitivity study on assessing the reliability of airborne electro-magnetic (EM) data for detecting channel orientation. The reliability results are used to calculate VOI regarding decisions of artificial recharge to mitigate seawater intrusion. To demonstrate how a hydrogeologic problem can be framed in decision analysis terms, a hypothetical example is built, where water managers are considering artificial recharge to remediate seawater intrusion. Is the cost of recharge justified given the large uncertainty of subsurface heterogeneity that may interfere in a successful recharge? Thus, the decision is should recharge be performed, and if yes, where should recharge wells be located? This decision is difficult because of the large uncertainty of the aquifer heterogeneity that influences flow. The expected value of all possible outcomes to the decision without gathering additional EM information is the prior value VPRIOR. The value of information (VOI) is calculated as the expected gain in value after including the relevant new information, or the difference between the value after a free experiment (VFE) and the value prior (VPRIOR): VOI = VFE - VPRIOR Airborne EM has been used to detect confining clay layers and flow barriers. However, geophysical information rarely identifies the subsurface perfectly. Many challenges impact data quality and the resulting models (interpretation uncertainty). To evaluate how well airborne EM data detect the orientation of subsurface channel systems, 125 alternative binary, fluvial lithology models are generated, each categorized into one of three subsurface scenarios: northwest, southwest and mixed channel orientation. Using rock property relations, the lithology models are converted into electrical resistivity models for EM forward modeling, to generate time-domain EM data. Noise is added to the late times of the EM data to better represent typical airborne acquisition. Inversions are performed to obtain 125 inverted resistivity images. From the images, we calculate the angle of maximum spatial correlation at every cell, and compare it with the truth - the original lithology model. These synthetic models serve as a proxy to estimate misclassification probabilities of channel orientation from actual EM data. The misclassification probabilities are then used in the VOI calculations. Results are presented demonstrating how the reliability measure and the pumping schedule can impact VOI. Lastly, reliability and VOI are calculated and compared for land-based EM data, which has different spatial sampling and resolution than air-borne data.

Trainor, W. J.; Caers, J. K.; Mukerji, T.; Auken, E.; Knight, R. J.

2008-12-01

152

Improving initial polyp candidate extraction for CT colonography  

NASA Astrophysics Data System (ADS)

Reducing the number of false positives (FPs) as much as possible is a challenging task for computer-aided detection (CAD) of colonic polyps. As part of a typical CAD pipeline, an accurate and robust process for segmenting initial polyp candidates (IPCs) will significantly benefit the successive FP reduction procedures, such as feature-based classification of false and true positives (TPs). In this study, we introduce an improved scheme for segmenting IPCs. It consists of two main components. One is geodesic distance-based merging, which merges suspicious patches (SPs) for IPCs. Based on the merged SPs, another component, called convex dilation, grows each SP beyond the inner surface of the colon wall to form a volume of interest (VOI) for that IPC, so that the inner border of the VOI beyond the colon inner surface could be segmented as convex, as expected. The IPC segmentation strategy was evaluated using a database of 50 patient studies, which include 100 scans at supine and prone positions with 84 polyps and masses sized from 6 to 35 mm. The presented IPC segmentation strategy (or VOI extraction method) demonstrated improvements, in terms of having no undesirably merged true polyp and providing more helpful mean and variance of the image intensities rooted from the extracted VOI for classification of the TPs and FPs, over two other VOI extraction methods (i.e. the conventional method of Nappi and Yoshida (2003 Med. Phys. 30 1592-601) and our previous method (Zhu et al 2009 Cancer Manag. Res. 1 1-13). At a by-polyp sensitivity of 0.90, these three methods generated the FP rate (number of FPs per scan) of 4.78 (new method), 6.37 (Nappi) and 7.01 (Zhu) respectively.

Zhu, Hongbin; Fan, Yi; Lu, Hongbing; Liang, Zhengrong

2010-04-01

153

Physiology and pathophysiology of glottic reflexes and pulmonary aspiration: from neonates to adults.  

PubMed

Pulmonary aspiration is the consequence of abnormal entry of fluid, particulate material, or endogenous secretions into the airway. The two main types of aspiration scenarios include anterograde aspiration, which occurs during swallowing, and retrograde aspiration, which can occur during gastroesophageal reflux (GER) events. The important structures that protect against aspiration include the aerodigestive apparatus: pharynx, upper esophageal sphincter, esophageal body, glottis and vocal cords, and airway. In this article we review the neuroanatomy, physiology, and pathophysiology pertinent to glottic reflexes and airway aspiration across the age spectrum from neonates to adults. We also discuss recent advances in our understanding of glottal reflexes and the relationship of these reflexes to developmental anatomy and physiology, the pathophysiology of aspiration, and aerodigestive interactions. PMID:20941656

Jadcherla, Sudarshan R; Hogan, Walter J; Shaker, Reza

2010-10-01

154

Physiology and Pathophysiology of Glottic Reflexes and Pulmonary Aspiration: From Neonates to Adults  

PubMed Central

Pulmonary aspiration is the consequence of abnormal entry of fluid, particulate material, or endogenous secretions into the airway. The two main types of aspiration scenarios include anterograde aspiration, which occurs during swallowing, and retrograde aspiration, which can occur during gastroesophageal reflux (GER) events. The important structures that protect against aspiration include the aerodigestive apparatus: pharynx, upper esophageal sphincter, esophageal body, glottis and vocal cords, and airway. In this article we review the neuroanatomy, physiology, and pathophysiology pertinent to glottic reflexes and airway aspiration across the age spectrum from neonates to adults. We also discuss recent advances in our understanding of glottal reflexes and the relationship of these reflexes to developmental anatomy and physiology, the pathophysiology of aspiration, and aerodigestive interactions.

Jadcherla, Sudarshan R.; Hogan, Walter J.; Shaker, Reza

2013-01-01

155

January 29-31, 2003: 7th EDRN Steering Committee Meeting  

Cancer.gov

The Early Detection Research Network Steering Committee meeting is devoted to discuss and conduct reviews of the network's research, collaborations, data sharing and dissemination, the network infrastructure, management, enrolment of associate members. Specific discussions will be conducted by the network collaborative group meetings (Breast and Gynecologic Cancers; G.I. and Other Associated Cancers; Lung and Upper Aerodigestive Cancers; Prostate and Urologic Cancers) and the data management and coordination center. This meeting has a special emphasis on validation and discovery studies.

156

September 3-6, 2002: EDRN Steering Committee Meeting  

Cancer.gov

The Early Detection Research Network Steering Committee meeting is devoted to discuss and conduct reviews of the network's research, collaborations, data sharing and dissemination, the network infrastructure, management, enrolment of associate members. Specific discussions will be conducted by the network collaborative group meetings (Breast and Gynecologic Cancers; G.I. and Other Associated Cancers; Lung and Upper Aerodigestive Cancers; Prostate and Urologic Cancers) and the data management and coordination center.

157

Neonatal linear immunoglobulin a bullous dermatosis: a rare presentation.  

PubMed

Linear immunoglobulin A bullous dermatosis (LABD) is an autoimmune blistering disease that most commonly presents in preschool-aged children. There have been few neonatal reports, all of which had life-threatening aerodigestive complications requiring mechanical intervention and systemic therapy. We present a case of LABD in a neonate who had an uncomplicated course and was treated conservatively with only low-potency topical corticosteroids and wound care before resolution of his skin lesions. PMID:21906150

Julapalli, Meena R; Brandon, Kirra L; Rosales, Cecilia M; Grover, Raminder K; Plunkett, Richard W; Metry, Denise W

2012-01-01

158

Alcohol Metabolism and Its Implications for Cancer  

Microsoft Academic Search

\\u000a As described in Chap. 1, alcohol has been classified as carcinogenic to humans at several sites in the body by the International\\u000a Agency for Research on Cancer (Secretan et al. 2009). These include the upper aero-digestive tract (UADT), liver, colon\\/rectum,\\u000a and female breast. Numerous mechanisms have been proposed for these multiple carcinogenic effects (Zakhari 2006). In this\\u000a chapter, we discuss

Gary J. Murray; Philip J. Brooks; Samir Zakhari

159

Lung cancer: From single-gene methylation to methylome profiling  

Microsoft Academic Search

DNA methylation as part of the epigenetic gene-silencing complex is a universal occurring change in lung cancer. Numerous\\u000a studies investigated methylation of specific genes in primary tumors, in serum or plasma samples, and in specimens from the\\u000a aerodigestive tract epithelium of lung cancer patients. In most studies, single genes or small numbers of genes were analyzed.\\u000a Moreover, it has been

Gerwin Heller; Christoph C. Zielinski; Sabine Zöchbauer-Müller

2010-01-01

160

DCTD Program Accomplishments 2010  

Cancer.gov

Barbara A. Conley, M.D., is the newly appointed Associate Director of the Cancer Diagnosis Program (CDP). She is an NCI veteran who has held previous positions at the Institute. From 1997 to 2004, she participated in several key programs within the NCI, including Senior Investigator in the Clinical Investigations Branch of CTEP and Chief of the CDP Diagnostics Research Branch, as well as Head, Aerodigestive Diseases, in the intramural medicine branch.

161

Controlling sialorrhoea: a review of available treatment options.  

PubMed

Sialorrhoea (drooling or excessive salivation) is a common symptom of many neurological diseases (e.g., amyotropic lateral sclerosis, cerebral palsy and Parkinson's disease) and otolaryngologic diseases (tumours of upper aerodigestive tract). It is mostly caused by poor oral and facial muscle control in patients with swallowing dysfunction (secondary sialorrhoea). However, some cases of sialorrhoea are due to hypersecretion of saliva. These cases represent so-called primary sialorrhoea. PMID:16086642

Potulska, Anna; Friedman, Andrzej

2005-08-01

162

Colon interposition in a patient with total postcricoid stenosis after caustic ingestion and preservation of full laryngeal function  

Microsoft Academic Search

Caustic burns of the upper aerodigestive tract continue to be a significant clinical problem. However, the available literature\\u000a uncommonly mentions changes affecting the larynx. We could find only one publication in which four cases of high hypopharyngeal\\u000a stenosis were described in detail and where the functional outcome of the laryngeal function was stated as partially saved.\\u000a We describe here a

Mieke B. J. Moerman; Kathy G. W. Bouche; Xavier Branquaer; Hubert F. E. Vermeersch

2000-01-01

163

Basaloid squamous cell carcinoma of retromolar trigone: A case report with review of literature  

PubMed Central

Basaloid squamous cell carcinoma (BSCC) is a rare distinct histologic variant of squamous - cell carcinoma of the head and neck region. BSCC is more aggressive and has a poorer prognosis, although histologically, it is associated with squamous cell carcinoma and squamous atypia. The usual site of occurrence for BSCC is the upper aerodigestive tract, floor of the mouth and base of the tongue. This is a case report of an unusual case of BSCC of retromolar trigone, which is quite rare.

Rachel, JR; Kumar, NS; Jain, NK

2011-01-01

164

Expectoration of a bullet after gunshot wound to the chest  

PubMed Central

Over the last century, only four cases have been published of patients sustaining gunshot wounds to the chest, managed nonoperatively, who eventually expectorated the bullet. We report the case of a hemodynamically stable 24-year-old male whose bullet was found in the left pulmonary hilum on admission computed tomography (CT) scan. Further workup revealed no obvious aerodigestive injury. Shortly after extubation, he expectorated the bullet onto the floor. Little is known about how to manage these stable, yet challenging patients.

Rhodes, Stancie C.; Gupta, Surupa S.

2013-01-01

165

Iatrogenic Migration of an Impacted Pharyngeal Foreign Body of the Hypopharynx to the Prevertebral Space  

PubMed Central

Impaction of foreign bodies in the upper aerodigestive tract is commonly encountered in ENT practice. The present paper describes an iatrogenic complication with migration of an impacted foreign body (chicken bone) of the hypopharynx into the prevertebral space, after unsuccessful attempt of endoscopic removal. The foreign body was visualized with cervical CT scan lying extraluminally between the major vessels of the neck. An open surgical procedure with neck exploration was necessary for the definite treatment.

Hajiioannou, Jiannis; Kousoulis, Panagiotis; Florou, Vassiliki; Stavrianou, Eleni

2011-01-01

166

Iatrogenic migration of an impacted pharyngeal foreign body of the hypopharynx to the prevertebral space.  

PubMed

Impaction of foreign bodies in the upper aerodigestive tract is commonly encountered in ENT practice. The present paper describes an iatrogenic complication with migration of an impacted foreign body (chicken bone) of the hypopharynx into the prevertebral space, after unsuccessful attempt of endoscopic removal. The foreign body was visualized with cervical CT scan lying extraluminally between the major vessels of the neck. An open surgical procedure with neck exploration was necessary for the definite treatment. PMID:22187562

Hajiioannou, Jiannis; Kousoulis, Panagiotis; Florou, Vassiliki; Stavrianou, Eleni

2011-01-01

167

Head and Neck Tumors: Surgery Perspective  

Microsoft Academic Search

\\u000a The extracranial head and neck region is complex and varied with respect to anatomy, physiology, and pathology. Squamous cell\\u000a carcinoma represents a large proportion of upper aerodigestive tract (sinonasal cavity, oral cavity, nasopharynx, oropharynx,\\u000a hypopharynx, and larynx) malignancies. However, the salivary glands have pathology ranging from mucoepidermoid to adenoid\\u000a cystic and adenocarcinoma. Likewise, common malignancies of the thyroid gland include

Gregory Y. Chin; Uttam K. Sinha

168

Squamous papilloma in the external auditory canal: A common lesion in an uncommon site  

PubMed Central

Squamous papillomas (SPs) are common benign neoplastic lesions, usually affecting the skin, oral mucosa, upper aerodigestive tract and genital organs. However, SPs of the external auditory canal (EAC) are rarely reported in the English literature. In this report, we present a 19-year-old female with left EAC SP. The etiology, natural course, diagnosis and management of this disease are discussed, with a brief review of the literature.

Chang, Ning-Chia; Chien, Chen-Yu; Wu, Chun-Chieh; Chai, Chee-Yin

2013-01-01

169

Optimal Excitation Wavelengths for In Vivo Detection of Oral Neoplasia Using Fluorescence Spectroscopy¶  

Microsoft Academic Search

There is no satisfactory mechanism to detect premalig- nant lesions in the upper aero-digestive tract. Fluores- cence spectroscopy has potential to bridge the gap be- tween clinical examination and invasive biopsy; however, optimal excitation wavelengths have not yet been deter- mined. The goals of this study were to determine optimal excitation-emission wavelength combinations to discrim- inate normal and precancerous\\/cancerous tissue,

Douglas L. Heintzelman; Urs Utzinger; Holger Fuchs; Andres Zuluaga; Kirk Gossage; Ann M. Gillenwater; Rhonda Jacob; Bonnie Kemp; Rebecca R. Richards-Kortum

2000-01-01

170

CRCHD - CRCHD Research - Principal Investigator: Joseph Califano, M.D.  

Cancer.gov

Dr. Joseph Califano is a Professor in the Department of Otolaryngology-Head and Neck Surgery and Oncology, Johns Hopkins Medical Institutions in Baltimore, Maryland. He is an active head and neck surgeon who treats tumors of the oral cavity, larynx, pharynx, neck, skull base, salivary glands, thyroid cancer, premalignant conditions of the upper aerodigestive tract, unknown primary head and neck squamous cell carcinoma, advance skin cancer, and melanoma.

171

The impact of 3D volume of interest definition on accuracy and precision of activity estimation in quantitative SPECT and planar processing methods  

NASA Astrophysics Data System (ADS)

Accurate and precise estimation of organ activities is essential for treatment planning in targeted radionuclide therapy. We have previously evaluated the impact of processing methodology, statistical noise and variability in activity distribution and anatomy on the accuracy and precision of organ activity estimates obtained with quantitative SPECT (QSPECT) and planar (QPlanar) processing. Another important factor impacting the accuracy and precision of organ activity estimates is accuracy of and variability in the definition of organ regions of interest (ROI) or volumes of interest (VOI). The goal of this work was thus to systematically study the effects of VOI definition on the reliability of activity estimates. To this end, we performed Monte Carlo simulation studies using randomly perturbed and shifted VOIs to assess the impact on organ activity estimates. The 3D NCAT phantom was used with activities that modeled clinically observed 111In ibritumomab tiuxetan distributions. In order to study the errors resulting from misdefinitions due to manual segmentation errors, VOIs of the liver and left kidney were first manually defined. Each control point was then randomly perturbed to one of the nearest or next-nearest voxels in three ways: with no, inward or outward directional bias, resulting in random perturbation, erosion or dilation, respectively, of the VOIs. In order to study the errors resulting from the misregistration of VOIs, as would happen, e.g. in the case where the VOIs were defined using a misregistered anatomical image, the reconstructed SPECT images or projections were shifted by amounts ranging from -1 to 1 voxels in increments of with 0.1 voxels in both the transaxial and axial directions. The activity estimates from the shifted reconstructions or projections were compared to those from the originals, and average errors were computed for the QSPECT and QPlanar methods, respectively. For misregistration, errors in organ activity estimations were linear in the shift for both the QSPECT and QPlanar methods. QPlanar was less sensitive to object definition perturbations than QSPECT, especially for dilation and erosion cases. Up to 1 voxel misregistration or misdefinition resulted in up to 8% error in organ activity estimates, with the largest errors for small or low uptake organs. Both types of VOI definition errors produced larger errors in activity estimates for a small and low uptake organs (i.e. -7.5% to 5.3% for the left kidney) than for a large and high uptake organ (i.e. -2.9% to 2.1% for the liver). We observed that misregistration generally had larger effects than misdefinition, with errors ranging from -7.2% to 8.4%. The different imaging methods evaluated responded differently to the errors from misregistration and misdefinition. We found that QSPECT was more sensitive to misdefinition errors, but less sensitive to misregistration errors, as compared to the QPlanar method. Thus, sensitivity to VOI definition errors should be an important criterion in evaluating quantitative imaging methods.

He, Bin; Frey, Eric C.

2010-06-01

172

Optical biopsy fiber-based fluorescence spectroscopy instrumentation  

NASA Astrophysics Data System (ADS)

Native fluorescence spectroscopy of biomolecules has emerged as a new modality to the medical community in characterizing the various physiological conditions of tissues. In the past several years, many groups have been working to introduce the spectroscopic methods to diagnose cancer. Researchers have successfully used native fluorescence to distinguish cancerous from normal tissue samples in rat and human tissue. We have developed three generations of instruments, called the CD-scan, CD-ratiometer and CD-map, to allow the medical community to use optics for diagnosing tissue. Using ultraviolet excitation and emission spectral measurements on both normal and cancerous tissue of the breast, gynecology, colon, and aerodigestive tract can be separated. For example, from emission intensities at 340 nm to 440 nm (300 nm excitation), a statistically consistent difference between malignant tissue and normal or benign tissue is observed. In order to utilize optical biopsy techniques in a clinical setting, the CD-scan instrument was developed, which allows for rapid and reliable in-vitro and in-vivo florescence measurements of the aerodigestive tract with high accuracy. The instrumentation employs high sensitivity detection techniques which allows for lamp excitation, small diameter optical fiber probes; the higher spatial resolution afforded by the small diameter probes can increase the ability to detect smaller tumors. The fiber optic probes allow for usage in the aerodigestive tract, cervix and colon. Needle based fiber probes have been developed for in-vivo detection of breast cancer.

Katz, Al; Ganesan, S.; Yang, Yuan-Long; Tang, Gui C.; Budansky, Y.; Celmer, Edward J.; Savage, Howard E.; Schantz, Stimson P.; Alfano, Robert R.

1996-04-01

173

Computerized detection of diffuse lung disease in MDCT: the usefulness of statistical texture features  

NASA Astrophysics Data System (ADS)

Accurate detection of diffuse lung disease is an important step for computerized diagnosis and quantification of this disease. It is also a difficult clinical task for radiologists. We developed a computerized scheme to assist radiologists in the detection of diffuse lung disease in multi-detector computed tomography (CT). Two radiologists selected 31 normal and 37 abnormal CT scans with ground glass opacity, reticular, honeycombing and nodular disease patterns based on clinical reports. The abnormal cases in our database must contain at least an abnormal area with a severity of moderate or severe level that was subjectively rated by the radiologists. Because statistical texture features may lack the power to distinguish a nodular pattern from a normal pattern, the abnormal cases that contain only a nodular pattern were excluded. The areas that included specific abnormal patterns in the selected CT images were then delineated as reference standards by an expert chest radiologist. The lungs were first segmented in each slice by use of a thresholding technique, and then divided into contiguous volumes of interest (VOIs) with a 64 × 64 × 64 matrix size. For each VOI, we determined and employed statistical texture features, such as run-length and co-occurrence matrix features, to distinguish abnormal from normal lung parenchyma. In particular, we developed new run-length texture features with clear physical meanings to considerably improve the accuracy of our detection scheme. A quadratic classifier was employed for distinguishing between normal and abnormal VOIs by the use of a leave-one-case-out validation scheme. A rule-based criterion was employed to further determine whether a case was normal or abnormal. We investigated the impact of new and conventional texture features, VOI size and the dimensionality for regions of interest on detecting diffuse lung disease. When we employed new texture features for 3D VOIs of 64 × 64 × 64 voxels, our system achieved the highest performance level: a sensitivity of 86% and a specificity of 90% for the detection of abnormal VOIs, and a sensitivity of 89% and a specificity of 90% for the detection of abnormal cases. Our computerized scheme would be useful for assisting radiologists in the diagnosis of diffuse lung disease.

Wang, Jiahui; Li, Feng; Doi, Kunio; Li, Qiang

2009-11-01

174

Computerized detection of diffuse lung disease in MDCT: the usefulness of statistical texture features.  

PubMed

Accurate detection of diffuse lung disease is an important step for computerized diagnosis and quantification of this disease. It is also a difficult clinical task for radiologists. We developed a computerized scheme to assist radiologists in the detection of diffuse lung disease in multi-detector computed tomography (CT). Two radiologists selected 31 normal and 37 abnormal CT scans with ground glass opacity, reticular, honeycombing and nodular disease patterns based on clinical reports. The abnormal cases in our database must contain at least an abnormal area with a severity of moderate or severe level that was subjectively rated by the radiologists. Because statistical texture features may lack the power to distinguish a nodular pattern from a normal pattern, the abnormal cases that contain only a nodular pattern were excluded. The areas that included specific abnormal patterns in the selected CT images were then delineated as reference standards by an expert chest radiologist. The lungs were first segmented in each slice by use of a thresholding technique, and then divided into contiguous volumes of interest (VOIs) with a 64 x 64 x 64 matrix size. For each VOI, we determined and employed statistical texture features, such as run-length and co-occurrence matrix features, to distinguish abnormal from normal lung parenchyma. In particular, we developed new run-length texture features with clear physical meanings to considerably improve the accuracy of our detection scheme. A quadratic classifier was employed for distinguishing between normal and abnormal VOIs by the use of a leave-one-case-out validation scheme. A rule-based criterion was employed to further determine whether a case was normal or abnormal. We investigated the impact of new and conventional texture features, VOI size and the dimensionality for regions of interest on detecting diffuse lung disease. When we employed new texture features for 3D VOIs of 64 x 64 x 64 voxels, our system achieved the highest performance level: a sensitivity of 86% and a specificity of 90% for the detection of abnormal VOIs, and a sensitivity of 89% and a specificity of 90% for the detection of abnormal cases. Our computerized scheme would be useful for assisting radiologists in the diagnosis of diffuse lung disease. PMID:19864701

Wang, Jiahui; Li, Feng; Doi, Kunio; Li, Qiang

2009-11-21

175

A General Local Reconstruction Approach Based on a Truncated Hilbert Transform  

PubMed Central

Exact image reconstruction from limited projection data has been a central topic in the computed tomography (CT) field. In this paper, we present a general region-of-interest/volume-of-interest (ROI/VOI) reconstruction approach using a truly truncated Hilbert transform on a line-segment inside a compactly supported object aided by partial knowledge on one or both neighboring intervals of that segment. Our approach and associated new data sufficient condition allows the most flexible ROI/VOI image reconstruction from the minimum account of data in both the fan-beam and cone-beam geometry. We also report primary numerical simulation results to demonstrate the correctness and merits of our finding. Our work has major theoretical potentials and innovative practical applications.

Ye, Yangbo; Yu, Hengyong; Wei, Yuchuan; Wang, Ge

2007-01-01

176

Exact Interior Reconstruction with Cone-Beam CT  

PubMed Central

Using the backprojection filtration (BPF) and filtered backprojection (FBP) approaches, respectively, we prove that with cone-beam CT the interior problem can be exactly solved by analytic continuation. The prior knowledge we assume is that a volume of interest (VOI) in an object to be reconstructed is known in a subregion of the VOI. Our derivations are based on the so-called generalized PI-segment (chord). The available projection onto convex set (POCS) algorithm and singular value decomposition (SVD) method can be applied to perform the exact interior reconstruction. These results have many implications in the CT field and can be extended to other tomographic modalities, such as SPECT/PET, MRI.

Ye, Yangbo; Yu, Hengyong; Wang, Ge

2007-01-01

177

Exact Interior Reconstruction from Truncated Limited-Angle Projection Data  

PubMed Central

Using filtered backprojection (FBP) and an analytic continuation approach, we prove that exact interior reconstruction is possible and unique from truncated limited-angle projection data, if we assume a prior knowledge on a subregion or subvolume within an object to be reconstructed. Our results show that (i) the interior region-of-interest (ROI) problem and interior volume-of-interest (VOI) problem can be exactly reconstructed from a limited-angle scan of the ROI/VOI and a 180 degree PI-scan of the subregion or subvolume and (ii) the whole object function can be exactly reconstructed from nontruncated projections from a limited-angle scan. These results improve the classical theory of Hamaker et al. (1980).

Ye, Yangbo; Yu, Hengyong; Wang, Ge

2008-01-01

178

Unsupervised tumour segmentation in PET using local and global intensity-fitting active surface and alpha matting.  

PubMed

This paper proposes an unsupervised tumour segmentation approach for PET data. The method computes the volumes of interest (VOIs) with sub-voxel precision by considering the limited image resolution and partial volume effects. First, an improved anisotropic diffusion filter is used to remove image noise. A hierarchical local and global intensity active surface modelling scheme is then applied to segment VOIs, followed by an alpha matting step to further refine the segmentation boundary. The proposed method is validated on real PET images of head-and-neck cancer patients with ground truth provided by human experts, as well as custom-designed phantom PET images with objective ground truth. Experimental results show that our method outperforms previous automatic approaches in terms of segmentation accuracy. PMID:24034745

Zeng, Ziming; Wang, Jue; Tiddeman, Bernie; Zwiggelaar, Reyer

2013-10-01

179

Audio-signal watermarking in 3-D space based on virtual-optics  

NASA Astrophysics Data System (ADS)

This paper presents a new approach for audio-signal watermarking in three-dimensional (3-D) space. The method proposed in this paper offers an efficient way of copyright protection of audio signal through a virtual-optical-imaging scheme (VOIS). The watermarking method presented here does not require the use of original signal for watermark detection. Besides, this scheme is of a high-strength security system with multiple locks and multiple keys. The embedding strategy of a watermark with a methodology of the VOIS is analyzed in detail under the framework of Fourier optics. The embedded watermark is robust to normal signal manipulations. Numerical simulation results show a good agreement with theoretical prediction.

Peng, Xiang; Zhang, Peng; Niu, Hanben

180

The annealing of interstitial carbon atoms in high-resistivity n-type silicon after proton irradiation  

Microsoft Academic Search

The annealing of interstitial carbon Ci after 7–10MeV and 23GeV proton irradiations at room temperature in high-resistivity n-type silicon is investigated. Deep level transient spectroscopy is used to determine the defect parameters. The annealing characteristics of the impurity defects Ci, CiCs, CiOi and VOi suggest that the mobile Ci atoms are also captured at divacancy VV sites at the cluster

M. Kuhnke; E. Fretwurst; G. Lindstroem

2002-01-01

181

Corrections of arterial input function for dynamic H215O PET to assess perfusion of pelvic tumours: arterial blood sampling versus image extraction  

NASA Astrophysics Data System (ADS)

Assessment of perfusion with 15O-labelled water (H215O) requires measurement of the arterial input function (AIF). The arterial time activity curve (TAC) measured using the peripheral sampling scheme requires corrections for delay and dispersion. In this study, parametrizations with and without arterial spillover correction for fitting of the tissue curve are evaluated. Additionally, a completely noninvasive method for generation of the AIF from a dynamic positron emission tomography (PET) acquisition is applied to assess perfusion of pelvic tumours. This method uses a volume of interest (VOI) to extract the TAC from the femoral artery. The VOI TAC is corrected for spillover using a separate tissue TAC and for recovery by determining the recovery coefficient on a coregistered CT data set. The techniques were applied in five patients with pelvic tumours who underwent a total of 11 examinations. Delay and dispersion correction of the blood TAC without arterial spillover correction yielded in seven examinations solutions inconsistent with physiology. Correction of arterial spillover increased the fitting accuracy and yielded consistent results in all patients. Generation of an AIF from PET image data was investigated as an alternative to arterial blood sampling and was shown to have an intrinsic potential to determine the AIF noninvasively and reproducibly. The AIF extracted from a VOI in a dynamic PET scan was similar in shape to the blood AIF but yielded significantly higher tissue perfusion values (mean of 104.0 ± 52.0%) and lower partition coefficients (-31.6 ± 24.2%). The perfusion values and partition coefficients determined with the VOI technique have to be corrected in order to compare the results with those of studies using a blood AIF.

Lüdemann, L.; Sreenivasa, G.; Michel, R.; Rosner, C.; Plotkin, M.; Felix, R.; Wust, P.; Amthauer, H.

2006-06-01

182

Partial volume effect estimation and correction in the aortic vascular wall in PET imaging.  

PubMed

We evaluated the impact of partial volume effect (PVE) in the assessment of arterial diseases with (18)FDG PET. An anthropomorphic digital phantom enabling the modeling of aorta related diseases like atherosclerosis and arteritis was used. Based on this phantom, we performed GATE Monte Carlo simulations to produce realistic PET images with a known organ segmentation and ground truth activity values. Images corresponding to 15 different activity-concentration ratios between the aortic wall and the blood and to 7 different wall thicknesses were generated. Using the PET images, we compared the theoretical wall-to-blood activity-concentration ratios (WBRs) with the measured WBRs obtained with five measurement methods: (1) measurement made by a physician (Expert), (2) automated measurement supposed to mimic the physician measurements (Max), (3) simple correction based on a recovery coefficient (Max-RC), (4) measurement based on an ideal VOI segmentation (Mean-VOI) and (5) measurement corrected for PVE using an ideal geometric transfer matrix (GTM) method. We found that Mean-VOI WBRs values were strongly affected by PVE. WBRs obtained by the physician measurement, by the Max method and by the Max-RC method were more accurate than WBRs obtained with the Mean-VOI approach. However Expert, Max and Max-RC WBRs strongly depended on the wall thickness. Only the GTM corrected WBRs did not depend on the wall thickness. Using the GTM method, we obtained more reproducible ratio values that could be compared across wall thickness. Yet, the feasibility of the implementation of a GTM-like method on real data remains to be studied. PMID:24099932

Burg, S; Dupas, A; Stute, S; Dieudonné, A; Huet, P; Le Guludec, D; Buvat, I

2013-11-01

183

Comprendre le dialogue: l’interaction entre les micro-organismes et l’hôte  

Microsoft Academic Search

RésuméLe tube digestif des mammifères est beaucoup plus complexe qu’on ne le pensait précédemment. Une couche unique de cellules épithéliales recouvre la totalité des voies digestives, représentant ainsi l’interface la plus étendue avec l’environnement. L’épithélium digestif est un capteur de l’environnement intraluminal et contrôle non seulement les fonctions digestives, absorptives et sécrétoires, mais de plus transmet des informations aux systèmes

Alessio Fasano

2009-01-01

184

Le Hericium erinaceus: des propriétés essentiellement dépendantes du neuronal growth factor  

Microsoft Academic Search

Résumé  Le Hericium erinaceus (HE) induit la synthèse de neuronal growth factor (NGF), impliqué dans les maladies neurodégénératives comme la maladie d’Alzheimer ou plus généralement dans les troubles\\u000a trophiques (estomac, intestin, foie) ou les cicatrisations (peau, cartilage, os). Le HE stimule aussi les voies TH1 et TH2\\u000a (antiparasitaire puissant), ce qui le positionne parmi les aliments potentiellement utiles contre les maladies

B. Donatini

2011-01-01

185

Security of virtual-optics-based cryptosystem  

Microsoft Academic Search

We present a security analysis to the virtual optics (VO)-based cryptosystems, in which several aspects affecting security strength of the algorithm involved in such systems are considered. We start with the evaluation of the computational complexities of virtual-optical-imaging (VOI)-based and virtual-optical-holography (VOH)-based cryptosystems as the security strength of a cryptosystem is relevant to its computational complexity. Furthermore, we assess the

Xiang Peng; Peng Zhang

2006-01-01

186

Etude expérimentale IN VITRO du comportement rhéologique du sang en régime transitoire à faible vitesse de cisaillement  

Microsoft Academic Search

Résumé Des écoulements de type Couette en régime transitoire sont produits au moyen d'un microviscosimètre semi-automatique à cylindres coaxiaux muni d'un asservissement de la vitesse de rotation et d'un enregistreur à deux voies, et qui peut être associé à un générateur de fonction basse fréquence permettant de programmer la vitesse de rotation du cylindre extérieur du viscosimètre. Diverses sortes de

M. Bureau; J. C. Healy; D. Bourgoin; M. Joly

1978-01-01

187

Comparison of anatomic coordinate systems with rigid multi-resolution 3D registration for the reproducible positioning of analysis volumes of interest in QCT.  

PubMed

In this study we compared two approaches that have recently been used to minimize precision errors in 3D quantitative computed tomography (QCT) images of the hip and the spine in order to optimize the detection of longitudinal changes in bone mineral density (BMD). In 30 subjects we obtained baseline and 1 year follow-up 3D CT scans of the proximal femur and the spine. QCT analysis was applied to a variety of volumes of interest (VOIs) automatically positioned relative to anatomic coordinate systems (ACS). In the first approach (A1) baseline and follow-up scans were analyzed independently. In the second approach (A2) a 3D versor-based rigid intensity registration method was applied to match baseline and follow-up images, and the baseline ACS was mapped on the follow-up image using the registration transformation. Afterwards, the analysis VOIs were again independently calculated for baseline and follow-up images. There were no significant differences of percent BMD changes between baseline and follow-up images between A1 and A2 for any of the VOIs investigated. With advanced image processing methods a time-consuming 3D registration between baseline and follow-up images before the analysis does not improve analysis precision compared to the use of anatomical coordinate systems. PMID:20150681

Eisa, Fabian; Museyko, Oleg; Hess, Andreas; Kalender, Willi A; Engelke, Klaus

2010-03-01

188

Applied Use Value of Scientific Information for Management of Ecosystem Services  

NASA Astrophysics Data System (ADS)

The U.S. Geological Survey has developed and applied methods for quantifying the value of scientific information (VOI) that are based on the applied use value of the information. In particular the applied use value of U.S. Geological Survey information often includes efficient management of ecosystem services. The economic nature of U.S. Geological Survey scientific information is largely equivalent to that of any information, but we focus application of our VOI quantification methods on the information products provided freely to the public by the U.S. Geological Survey. We describe VOI economics in general and illustrate by referring to previous studies that use the evolving applied use value methods, which includes examples of the siting of landfills in Louden County, the mineral exploration efficiencies of finer resolution geologic maps in Canada, and improved agricultural production and groundwater protection in Eastern Iowa possible with Landsat moderate resolution satellite imagery. Finally, we describe the adaptation of the applied use value method to the case of streamgage information used to improve the efficiency of water markets in New Mexico.

Raunikar, R. P.; Forney, W.; Bernknopf, R.; Mishra, S.

2012-12-01

189

Are head-to-head trials of biologics needed? The role of value of information methods in arthritis research.  

PubMed

Reimbursement decisions are typically based on cost-effectiveness analyses. While a cost-effectiveness analysis can identify the optimum strategy, there is usually some degree of uncertainty around this decision. Sources of uncertainty include statistical sampling error in treatment efficacy measures, underlying baseline risk, utility measures and costs, as well as uncertainty in the structure of the model. The optimal strategy is therefore only optimal on average, and a decision to adopt this strategy might still be the wrong decision if all uncertainty could be eliminated. This means that there is a quantifiable expected (average) loss attaching to decisions made under uncertainty, and hence a value in collecting information to reduce that uncertainty. Value of information (VOI) analyses can be used to provide guidance on whether more research would be cost-effective, which particular model inputs (parameters) have the most bearing on decision uncertainty, and can also help with the design and sample size of further research. Here, we introduce the key concepts in VOI analyses, and highlight the inputs required to calculate it. The adoption of the new biologic treatments for RA and PsA tends to be based on placebo-controlled trials. We discuss the possible role of VOI analyses in deciding whether head-to-head comparisons of the biologic therapies should be carried out, illustrating with examples from other fields. We emphasize the need for a model of the natural history of RA and PsA, which reflects a consensus view. PMID:21859701

Welton, Nicky J; Madan, Jason; Ades, Anthony E

2011-09-01

190

Comparison of anatomic coordinate systems with rigid multi-resolution 3D registration for the reproducible positioning of analysis volumes of interest in QCT  

NASA Astrophysics Data System (ADS)

In this study we compared two approaches that have recently been used to minimize precision errors in 3D quantitative computed tomography (QCT) images of the hip and the spine in order to optimize the detection of longitudinal changes in bone mineral density (BMD). In 30 subjects we obtained baseline and 1 year follow-up 3D CT scans of the proximal femur and the spine. QCT analysis was applied to a variety of volumes of interest (VOIs) automatically positioned relative to anatomic coordinate systems (ACS). In the first approach (A1) baseline and follow-up scans were analyzed independently. In the second approach (A2) a 3D versor-based rigid intensity registration method was applied to match baseline and follow-up images, and the baseline ACS was mapped on the follow-up image using the registration transformation. Afterwards, the analysis VOIs were again independently calculated for baseline and follow-up images. There were no significant differences of percent BMD changes between baseline and follow-up images between A1 and A2 for any of the VOIs investigated. With advanced image processing methods a time-consuming 3D registration between baseline and follow-up images before the analysis does not improve analysis precision compared to the use of anatomical coordinate systems.

Eisa, Fabian; Museyko, Oleg; Hess, Andreas; Kalender, Willi A.; Engelke, Klaus

2010-03-01

191

Interpretable whole-brain prediction analysis with GraphNet.  

PubMed

Multivariate machine learning methods are increasingly used to analyze neuroimaging data, often replacing more traditional "mass univariate" techniques that fit data one voxel at a time. In the functional magnetic resonance imaging (fMRI) literature, this has led to broad application of "off-the-shelf" classification and regression methods. These generic approaches allow investigators to use ready-made algorithms to accurately decode perceptual, cognitive, or behavioral states from distributed patterns of neural activity. However, when applied to correlated whole-brain fMRI data these methods suffer from coefficient instability, are sensitive to outliers, and yield dense solutions that are hard to interpret without arbitrary thresholding. Here, we develop variants of the Graph-constrained Elastic-Net (GraphNet), a fast, whole-brain regression and classification method developed for spatially and temporally correlated data that automatically yields interpretable coefficient maps (Grosenick et al., 2009b). GraphNet methods yield sparse but structured solutions by combining structured graph constraints (based on knowledge about coefficient smoothness or connectivity) with a global sparsity-inducing prior that automatically selects important variables. Because GraphNet methods can efficiently fit regression or classification models to whole-brain, multiple time-point data sets and enhance classification accuracy relative to volume-of-interest (VOI) approaches, they eliminate the need for inherently biased VOI analyses and allow whole-brain fitting without the multiple comparison problems that plague mass univariate and roaming VOI ("searchlight") methods. As fMRI data are unlikely to be normally distributed, we (1) extend GraphNet to include robust loss functions that confer insensitivity to outliers, (2) equip them with "adaptive" penalties that asymptotically guarantee correct variable selection, and (3) develop a novel sparse structured Support Vector GraphNet classifier (SVGN). When applied to previously published data (Knutson et al., 2007), these efficient whole-brain methods significantly improved classification accuracy over previously reported VOI-based analyses on the same data (Grosenick et al., 2008; Knutson et al., 2007) while discovering task-related regions not documented in the original VOI approach. Critically, GraphNet estimates fit to the Knutson et al. (2007) data generalize well to out-of-sample data collected more than three years later on the same task but with different subjects and stimuli (Karmarkar et al., submitted for publication). By enabling robust and efficient selection of important voxels from whole-brain data taken over multiple time points (>100,000 "features"), these methods enable data-driven selection of brain areas that accurately predict single-trial behavior within and across individuals. PMID:23298747

Grosenick, Logan; Klingenberg, Brad; Katovich, Kiefer; Knutson, Brian; Taylor, Jonathan E

2013-05-15

192

Impact of partial volume effect correction on cerebral ?-amyloid imaging in APP-Swe mice using [(18)F]-florbetaben PET.  

PubMed

We previously investigated the progression of ?-amyloid deposition in brain of mice over-expressing amyloid-precursor protein (APP-Swe), a model of Alzheimer's disease (AD), in a longitudinal PET study with the novel ?-amyloid tracer [(18)F]-florbetaben. There were certain discrepancies between PET and autoradiographic findings, which seemed to arise from partial volume effects (PVE). Since this phenomenon can lead to bias, most especially in the quantitation of brain microPET studies of mice, we aimed in the present study to investigate the magnitude of PVE on [(18)F]-florbetaben quantitation in murine brain, and to establish and validate a useful correction method (PVEC). Phantom studies with solutions of known radioactivity concentration were performed to measure the full-width-at-half-maximum (FWHM) resolution of the Siemens Inveon DPET and to validate a volume-of-interest (VOI)-based PVEC algorithm. Several VOI-brain-masks were applied to perform in vivo PVEC on [(18)F]-florbetaben data from C57BL/6(N=6) mice, while uncorrected and PVE-corrected data were cross-validated with gamma counting and autoradiography. Next, PVEC was performed on longitudinal PET data set consisting of 43 PET scans in APP-Swe (13-20months) and age-matched wild-type (WT) mice using the previously defined masks. VOI-based cortex-to-cerebellum ratios (SUVR) were compared for uncorrected and PVE-corrected results. Brains from a subset of transgenic mice were ultimately examined by autoradiography ex vivo and histochemistry in vitro as gold standard assessments, and compared to VOI-based PET results. The phantom study indicated a FWHM of 1.72mm. Applying a VOI-brain-mask including extracerebral regions gave robust PVEC, with increased precision of the SUVR results. Cortical SUVR increased with age in APP-Swe mice compared to baseline measurements (16months: +5.5%, p<0.005; 20months: +15.5%, p<0.05) with uncorrected data, and to a substantially greater extent with PVEC (16months: +12.2% p<0.005; 20months: +36.4% p<0.05). WT animals showed no binding changes, irrespective of PVEC. Relative to autoradiographic results, the error [%] for uncorrected cortical SUVR was 18.9% for native PET data, and declined to 4.8% upon PVEC, in high correlation with histochemistry results. We calculate that PVEC increases by 10% statistical power for detecting altered [(18)F]-florbetaben uptake in aging APP-Swe mice in planned studies of disease modifying treatments on amyloidogenesis. PMID:24055703

Brendel, Matthias; Delker, Andreas; Rötzer, Christina; Böning, Guido; Carlsen, Janette; Cyran, Clemens; Mille, Erik; Gildehaus, Franz Josef; Cumming, Paul; Baumann, Karlheinz; Steiner, Harald; Haass, Christian; Herms, Jochen; Bartenstein, Peter; Rominger, Axel

2014-01-01

193

 

PubMed Central

SUMMARY Narrow band imaging and high definition television are recent innovations in upper aero-digestive tract endoscopy. Aim of this prospective, non-randomized, unblinded study was to establish the diagnostic advantage of these procedures in the evaluation of squamous cell cancer arising from various upper aero-digestive tract sites. Between April 2007 and January 2010, 444 patients affected by upper aero-digestive tract squamous cell cancer, or previously treated for it, were evaluated by white light and narrow band imaging ± high definition television endoscopy, both in the pre-/intra-operative setting and during follow-up. Tumour resection was performed taking into account narrow band imaging and high definition television information to obtain histopathologic confirmation of their validity. Endoscopic and pathologic data were subsequently matched to obtain sensitivity, specificity, positive, negative predictive values, and accuracy. Overall, 110 (25%) patients showed adjunctive findings by narrow band imaging ± high definition television when compared to standard white light endoscopy. Of these patients, 98 (89%) received histopatological confirmation. The sensitivity, specificity, positive, negative predictive values, and accuracy for white light-high definition television were 41%, 92%, 87%, 82%, and 67%, for narrow band imaging alone 75%, 87%, 87%, 74%, and 80%, and for narrow band imaging-high definition television 97%, 84%, 88%, 96%, and 92%. The highest diagnostic gain was observed in the oral cavity and oropharynx (25%). Narrow band imaging and high definition television were of value in the definition of superficial tumour extension, and in the detection of synchronous lesions in the pre-/intra-operative settings. These technologies also played an important role during post-treatment surveillance for early detection of persistences, recurrences, and metachronous tumours.

PIAZZA, C.; COCCO, D.; DEL BON, F.; MANGILI, S.; NICOLAI, P.; PERETTI, G.

2011-01-01

194

Incidence and localization of abnormal mucosa findings in patients consulting ENT outpatient clinics and data analysis of a cancer registry.  

PubMed

For patients without symptoms and at risk, there is no established early detection program to discover carcinomas of the upper aerodigestive tract in the sense of secondary prevention. Such type of prevention seems even more desirable because the chances for a cure and the quality of life are strongly dependent on the stage of the tumor and the time of the initial diagnosis. Six hundred and eight patients without symptoms but at least one of the self-reported risk factors "smoking", "alcohol consumption" or "reflux" were examined with an endoscope or an optical microscope for pathological findings in the upper aerodigestive tract once a year. In addition, the incidence of malignancies of the upper aerodigestive tract between 2001 and 2010 was determined through the Cancer Registry of Schleswig-Holstein. Tissue samples were taken from 18 of the 608 patients. Eleven patients (1.8 %) had a squamous cell carcinoma. Another patient suffered from non-Hodgkin's lymphoma and one from larynx tuberculosis. The ratio of detected malignancies in the oral cavity and the oropharynx on the one hand and the hypopharynx and larynx, which can only be examined by endoscopes, on the other hand were in our cohorts and in our survey according to the cancer registry was 5/6. The above-described methods allow examining risk patients easily and safely. According to current publications, the ratio of the found malignancies exceeds the expected ratio significantly, which presumably was caused by the examination targeting patients at risk. Due to the expanded examination area using optical instruments more than doubles the rate of discoverable malignancies compared to the limitations posed by the examination of directly visible areas of the oral cavity of the oropharynx. PMID:24114062

Löhler, J; Gerstner, A O H; Bootz, F; Walther, L E

2014-05-01

195

Delayed presentation of an undiscovered nasopharyngeal foreign body.  

PubMed

Suspected paediatric aerodigestive tract foreign body (FB) ingestion or aspiration is a commonly encountered emergency. Management may require a general anaesthetic for retrieval with bronchoscopy, laryngoscopy and oesophagoscopy, each dependent on the history and investigations of the case in question. We describe the case of a foreign body, which was missed in the nasopharynx for more than 3 years and also discuss how pressures on National Health Service (NHS) referral and follow-up patterns may have altered the time course of the eventual discovery. PMID:24925536

Ramdoo, Krishan; Manjaly, Joseph G; Tatla, Taran

2014-01-01

196

Primary myxoid liposarcoma of the supraglottic larynx  

PubMed Central

Sarcomas are a rare occurrence accounting for roughly 1% of all cancer cases reported. Of these, 9–18% will be identified as liposarcoma. Overall, only 4–9% of all liposarcomas occur in the head and neck region. As such, it is a rare event to see a primary liposarcoma of the aerodigestive tract. These tumors are typically misdiagnosed secondary to their indolent, asymptomatic course and similarities in appearance to other benign lesions. An understanding of these lesions will help clinicians appropriately manage their patients. We present a case of a 60-year male with a primary supraglottic myxoid liposarcoma, and provide relevant information about liposarcomas.

Gleinser, David M; Font, Jean Paul; Clement, Cecilia G; Mohammed, Basim S; Underbrink, Michael P

2010-01-01

197

Nuclear medicine and molecular imaging of the pediatric chest: current practical imaging assessment.  

PubMed

In the chest, the indications for nuclear medicine studies are broader and more varied in children than in adults. In children, nuclear medicine studies are used to evaluate congenital and developmental disorders of the chest, as well as diseases more typical of adults. In the chest, pediatric nuclear medicine uses the same radiopharmaceuticals and imaging techniques as used in adults to evaluate cardiac and pulmonary disease, aerodigestive disorders, and pediatric malignancies. The introduction of PET (mostly using (18)F-FDG) has transformed pediatric nuclear oncology, particular for imaging malignancies in the chest. PMID:21889020

Grant, Frederick D; Treves, S Ted

2011-09-01

198

Incidence of cranial nerve dysfunction following carotid endarterectomy.  

PubMed

An analysis of postoperative injuries to the recurrent laryngeal, hypoglossal, marginal mandibular, and superior laryngeal nerves was undertaken in 517 patients who underwent 535 carotid endarterectomies between April 1978 and March 1981 at The Cleveland Clinic Foundation. A review of the literature is presented followed by the results of this analysis and a discussion of the findings. Suggestions for decreasing or avoiding such injuries are made. Conclusions are drawn to help the otolaryngologist identify the endarterectomized patient with an impaired upper aerodigestive tract. PMID:6643076

Astor, F C; Santilli, P; Tucker, H M

1983-01-01

199

Acrokeratosis paraneoplastica (Bazex syndrome): report of a case associated with small cell lung carcinoma and review of the literature.  

PubMed

Acrokeratosis paraneoplastic (Bazex syndrome) is a rare, but distinctive paraneoplastic dermatosis characterized by erythematosquamous lesions located at the acral sites and is most commonly associated with carcinomas of the upper aerodigestive tract. We report a 58-year-old female with a history of a pigmented rash on her extremities, thick keratotic plaques on her hands, and brittle nails. Chest imaging revealed a right upper lobe mass that was proven to be small cell lung carcinoma. While Bazex syndrome has been described in the dermatology literature, it is also important for the radiologist to be aware of this entity and its common presentations. PMID:22470801

Zarzour, Jessica G; Singh, Satinder; Andea, Aleodor; Cafardi, Jennifer A

2011-01-01

200

Acrokeratosis paraneoplastica (Bazex syndrome): Report of a case associated with small cell lung carcinoma and review of the literature  

PubMed Central

Acrokeratosis paraneoplastic (Bazex syndrome) is a rare, but distinctive paraneoplastic dermatosis characterized by erythematosquamous lesions located at the acral sites and is most commonly associated with carcinomas of the upper aerodigestive tract. We report a 58-year-old female with a history of a pigmented rash on her extremities, thick keratotic plaques on her hands, and brittle nails. Chest imaging revealed a right upper lobe mass that was proven to be small cell lung carcinoma. While Bazex syndrome has been described in the dermatology literature, it is also important for the radiologist to be aware of this entity and its common presentations.

Zarzour, Jessica G.; Singh, Satinder; Andea, Aleodor; Cafardi, Jennifer A.

2011-01-01

201

Extramedullary plasmacytoma of the trachea.  

PubMed

Extramedullary plasmacytomas are plasma cell tumors that occur outside the bone marrow. They constitute around 4 % of all plasma cell neoplasms. The most common site of extramedullary plasmacytoma is the upper aerodigestive tract-nasal cavity, paranasal sinuses and oronasopharynx. We are presenting a case of extramedullary plasmacytoma of the trachea. Trachea is an extremely rare site of plasmacytoma. When extraosseous plasmacytoma occur in uncommon sites, the distinction from B cell lymphomas showing extensive plasmacytic differentiation can be difficult and diagnostically challenging. PMID:24046059

Sukumaran, Renu; Nair, Rekha A; Jacob, Priya Mary; Koshy, Sumod Mathew; Mathew, Arun Peter

2014-06-01

202

Treatment response assessment of breast masses on dynamic contrast-enhanced magnetic resonance scans using fuzzy c-means clustering and level set segmentation.  

PubMed

The goal of this study was to develop an automated method to segment breast masses on dynamic contrast-enhanced (DCE) magnetic resonance (MR) scans and to evaluate its potential for estimating tumor volume on pre- and postchemotherapy images and tumor change in response to treatment. A radiologist experienced in interpreting breast MR scans defined a cuboid volume of interest (VOI) enclosing the mass in the MR volume at one time point within the sequence of DCE-MR scans. The corresponding VOIs over the entire time sequence were then automatically extracted. A new 3D VOI representing the local pharmacokinetic activities in the VOI was generated from the 4D VOI sequence by summarizing the temporal intensity enhancement curve of each voxel with its standard deviation. The method then used the fuzzy c-means (FCM) clustering algorithm followed by morphological filtering for initial mass segmentation. The initial segmentation was refined by the 3D level set (LS) method. The velocity field of the LS method was formulated in terms of the mean curvature which guaranteed the smoothness of the surface, the Sobel edge information which attracted the zero LS to the desired mass margin, and the FCM membership function which improved segmentation accuracy. The method was evaluated on 50 DCE-MR scans of 25 patients who underwent neoadjuvant chemotherapy. Each patient had pre- and postchemotherapy DCE-MR scans on a 1.5 T magnet. The in-plane pixel size ranged from 0.546 to 0.703 mm and the slice thickness ranged from 2.5 to 4.5 mm. The flip angle was 15 degrees, repetition time ranged from 5.98 to 6.7 ms, and echo time ranged from 1.2 to 1.3 ms. Computer segmentation was applied to the coronal T1-weighted images. For comparison, the same radiologist who marked the VOI also manually segmented the mass on each slice. The performance of the automated method was quantified using an overlap measure, defined as the ratio of the intersection of the computer and the manual segmentation volumes to the manual segmentation volume. Pre- and postchemotherapy masses had overlap measures of 0.81 +/- 0.13 (mean +/- s.d.) and 0.71 +/- 0.22, respectively. The percentage volume reduction (PVR) estimated by computer and the radiologist were 55.5 +/- 43.0% (mean +/- s.d.) and 57.8 +/- 51.3%, respectively. Paired Student's t test indicated that the difference between the mean PVRs estimated by computer and the radiologist did not reach statistical significance (p = 0.641). The automated mass segmentation method may have the potential to assist physicians in monitoring volume change in breast masses in response to treatment. PMID:19994516

Shi, Jiazheng; Sahiner, Berkman; Chan, Heang-Ping; Paramagul, Chintana; Hadjiiski, Lubomir M; Helvie, Mark; Chenevert, Thomas

2009-11-01

203

Treatment response assessment of breast masses on dynamic contrast-enhanced magnetic resonance scans using fuzzy c-means clustering and level set segmentation  

PubMed Central

The goal of this study was to develop an automated method to segment breast masses on dynamic contrast-enhanced (DCE) magnetic resonance (MR) scans and to evaluate its potential for estimating tumor volume on pre- and postchemotherapy images and tumor change in response to treatment. A radiologist experienced in interpreting breast MR scans defined a cuboid volume of interest (VOI) enclosing the mass in the MR volume at one time point within the sequence of DCE-MR scans. The corresponding VOIs over the entire time sequence were then automatically extracted. A new 3D VOI representing the local pharmacokinetic activities in the VOI was generated from the 4D VOI sequence by summarizing the temporal intensity enhancement curve of each voxel with its standard deviation. The method then used the fuzzy c-means (FCM) clustering algorithm followed by morphological filtering for initial mass segmentation. The initial segmentation was refined by the 3D level set (LS) method. The velocity field of the LS method was formulated in terms of the mean curvature which guaranteed the smoothness of the surface, the Sobel edge information which attracted the zero LS to the desired mass margin, and the FCM membership function which improved segmentation accuracy. The method was evaluated on 50 DCE-MR scans of 25 patients who underwent neoadjuvant chemotherapy. Each patient had pre- and postchemotherapy DCE-MR scans on a 1.5 T magnet. The in-plane pixel size ranged from 0.546 to 0.703 mm and the slice thickness ranged from 2.5 to 4.5 mm. The flip angle was 15°, repetition time ranged from 5.98 to 6.7 ms, and echo time ranged from 1.2 to 1.3 ms. Computer segmentation was applied to the coronal T1-weighted images. For comparison, the same radiologist who marked the VOI also manually segmented the mass on each slice. The performance of the automated method was quantified using an overlap measure, defined as the ratio of the intersection of the computer and the manual segmentation volumes to the manual segmentation volume. Pre- and postchemotherapy masses had overlap measures of 0.81±0.13 (mean±s.d.) and 0.71±0.22, respectively. The percentage volume reduction (PVR) estimated by computer and the radiologist were 55.5±43.0% (mean±s.d.) and 57.8±51.3%, respectively. Paired Student’s t test indicated that the difference between the mean PVRs estimated by computer and the radiologist did not reach statistical significance (p=0.641). The automated mass segmentation method may have the potential to assist physicians in monitoring volume change in breast masses in response to treatment.

Shi, Jiazheng; Sahiner, Berkman; Chan, Heang-Ping; Paramagul, Chintana; Hadjiiski, Lubomir M.; Helvie, Mark; Chenevert, Thomas

2009-01-01

204

The Economic Value of Climate Science  

NASA Astrophysics Data System (ADS)

While demonstrating the economic value of science is challenging, it can be more direct for some Earth observations. For example, suppose a climate science mission can yield decisive information on climate change within a shortened time frame. How much should society be willing to pay for this knowledge today? The US interagency memo on the social cost of carbon (SCC) provides a standard for valuing damages from carbon emissions. We illustrate how value of information (VOI) calculations can be used to monetize the relative value of different climate observations. We follow the SCC, stipulating uncertainty in climate sensitivity, using discount rates of 2.5%, 3% and 5%, and using one of the Integrated Assessment Models sanctioned in SCC (DICE, Nordhaus 2008). We consider three mitigation scenarios: Business as Usual (BAU), a moderate response (DICE Optimal), and a strong response (Stern). To illustrate results, suppose that we would switch from BAU to the Stern emissions path if we learn with 90% confidence that the decadal rate of temperature change reaches or exceeds 0.2 C/decade. Under the SCC assumptions, the year in which this happens, if it happens, depends on uncertain climate sensitivity and on the emissions path. The year in which we become 90% certain also depends on our Earth observations, their accuracy, and their completeness. The resolving power of a climate observing system cannot exceed climate system natural variability. All climate observations add noise to natural variability caused by observing limitations, including calibration errors and space/time sampling uncertainty. The basic concept is that more accurate observations can advance the time for societal decisions. The economic value of the resulting averted damages depends on the discount rate, and the years in which the damages occur. A new climate observation would be economically justified if the net present value (NPV) of the difference in averted damages, relative to the existing systems, exceeds the NPV of the system costs. We present illustrative results comparing the proposed CLARREO advance in satellite absolute calibration for climate change records to an existing system for detecting decadal temperature change and cloud feedback (i.e. climate sensitivity uncertainty). While CLARREO is used as an example, the value should be considered as relevant to an improved climate observing system, since societal decisions are unlikely to be based on one or a few observations. The VOI is found to depend on the required confidence level, the trigger value at which we would abandon the BAU emissions path, the path to which we switch, and the date at which the new system is launched. The VOI of CLARREO in this decision context is the surfeit of NPV of averted damages, relative to the existing system. Over all it is in the order of tens of trillions of US dollars. Among the noteworthy conclusions are (1) switching to either the DICE optimal or Stern emissions paths makes only a modest difference in the VOI of CLARREO, (2) raising the trigger value from 0.2C to 0.3C/decade, increases the VOI of CLARREO, while increasing the total NPV of climate damages, and (3) the choice of discount rate affects the VOI by a factor ~ 5. The results conclude that the economic value of advanced climate observing systems is dramatically larger than their cost, and argues for the continual enhancement of the SCC assessment process.

Wielicki, B. A.; Cooke, R.; Young, D. F.; Mlynczak, M. G.

2012-12-01

205

Strawberry gingivitis: A diagnostic feature of gingival Wegener's granulomatosis!  

PubMed Central

Wegener's granulomatosis (WG) is an immunologically mediated inflammatory disease characterized by granulomatous vasculitis of the upper and lower aerodigestive tracts together with glomerulonephritis. We are reporting a rare case of gingival WG that presented with erythematous and painful generalized gingival enlargement. Correlation of histopathology with routine hematoxylin and eosin and special stains [Grocott-Gomori methenamine-silver nitrate and Periodic Acid Schiff (PAS)], Mantoux test, peripheral blood smear and clinical presentation were established in diagnosing this rare entity. By the above-mentioned procedures and methodology, we have arrived at the diagnosis of Wegner's granulomatosis limited to the upper aerodigestive tract. Therefore, the aim of reporting this case was to emphasize that, the dental surgeon often being the first person to examine the oral cavity, should be familiar with the typical appearance of gingival WG as “strawberry gingivitis,” its clinical course as well as diagnostic parameters and adequate management. To the best of our knowledge, this is the first reported case of WG manifesting as “strawberry gingivitis” in the Indian population.

Heera, R.; Choudhary, Kanaram; Beena, V. T.; Simon, Rency

2012-01-01

206

Strawberry gingivitis: A diagnostic feature of gingival Wegener's granulomatosis!  

PubMed

Wegener's granulomatosis (WG) is an immunologically mediated inflammatory disease characterized by granulomatous vasculitis of the upper and lower aerodigestive tracts together with glomerulonephritis. We are reporting a rare case of gingival WG that presented with erythematous and painful generalized gingival enlargement. Correlation of histopathology with routine hematoxylin and eosin and special stains [Grocott-Gomori methenamine-silver nitrate and Periodic Acid Schiff (PAS)], Mantoux test, peripheral blood smear and clinical presentation were established in diagnosing this rare entity. By the above-mentioned procedures and methodology, we have arrived at the diagnosis of Wegner's granulomatosis limited to the upper aerodigestive tract. Therefore, the aim of reporting this case was to emphasize that, the dental surgeon often being the first person to examine the oral cavity, should be familiar with the typical appearance of gingival WG as "strawberry gingivitis," its clinical course as well as diagnostic parameters and adequate management. To the best of our knowledge, this is the first reported case of WG manifesting as "strawberry gingivitis" in the Indian population. PMID:23814553

Heera, R; Choudhary, Kanaram; Beena, V T; Simon, Rency

2012-12-01

207

Upstream Effect of Esophageal Distention: Effect on Airway  

PubMed Central

The pharyngoesophageal segment of the foregut has an important function in steering clear of luminal contents from the airway, across the age spectrum from a premature neonate to an aging adult. This complex neuromuscular interaction between the esophagus and the airway is maintained by a variety of mechanisms mediated by the parasympathetic and sympathetic afferent and efferent outflows involving the myenteric plexus, glossopharyngeal and vagus cranial nerves, phrenic nerve, and brainstem nuclei. The esophageal provocation during gastroesophageal reflux events results in esophageal distention, followed by responses in the esophagus, the airway, or both. Studies involving esophageal provocation in human adults and animal models are beginning to illuminate the pathogenetic mechanisms associated with aerodigestive tract disease. However, studies pertinent to this topic in infants or children have been lacking. In this paper, we review recent advances concerning the motor responses of the esophagus and the airway ensuing upon esophageal distention. Recent advances in methods to evaluate aerodigestive responses in infants that have been validated are discussed.

Jadcherla, Sudarshan R.

2014-01-01

208

Pharyngo-laryngeal examination with the narrow band imaging technology: early experience.  

PubMed

The prognosis of cancer patients is highly dependent on the time of diagnosis. Early, stage 1 disease is often curable whereas late stage diseases are usually beyond curable treatments. Therefore, new diagnostic tools for malignancies of the upper aerodigestive tract are developed all the time and narrow band imaging (NBI) is one of these new options for early diagnostics. In this paper, we describe the implementation of NBI technique in our institution. During the first 6 weeks we used NBI to examine 73 patients with different types of pharyngeal or laryngeal problems. Most of the patients (77%) were on follow-up visits after earlier malignant disease. In our series we had 11 NBI-positive patients and the histological diagnosis was carcinoma or dysplasia among 10 of these. Among the NBI negative patients we found four carcinomas. It is notable that NBI affected the decision of a biopsy procedure in three patients, with final diagnosis of dysplasia or carcinoma. In conclusion, we find NBI useful in the diagnostics of malignancies of the upper aerodigestive tract. This is a useful tool in improving the accuracy of the diagnostics. However, it still takes an experienced clinician and a learning curve can be expected. PMID:21327999

Irjala, Heikki; Matar, Nayla; Remacle, Marc; Georges, Lawson

2011-06-01

209

7, 12 dimethylbenz(a)anthracene(DMBA)-induced "early" Squamous Cell carcinoma in the Golden Syrian hamster: evaluation of an animal model and comparison with "early" forms of human Squamous Cell car  

NASA Astrophysics Data System (ADS)

To improve our knowledge on PDT of human early squamous cell carcinomas of the upper aero-digestive tract and to evaluate new photosensitizers, we have set up the Syrian hamster as an animal model. A 0.5% oily solution of DMBA was applied topically to the left buccal pouch mucosa 3 times weekly. The contralateral buccal pouch served as control. Groups of 5 animals were sacrificed at 6, 8, 10 and 12 weeks from the first applications. Tissue samples of the buccal mucosa were analyzed by histopathologic and immunohistochemical techniques and compared with preneoplastic and neoplastic changes which are seen in the human carcinogenesis of the upper aero-digestive tract. After 6 to 9 weeks from the beginning of the application, we observed different degrees of epithelial dysplasia and after 10 weeks microinvasive carcinomas. The sequence of dysplastic changes to early carcinoma was reproducible in different groups of animals, and they were closely comparable with the human forms of `early' squamous cell cancer. Hyper- and dyskeratosis were present at all stages of tumor development. We are particularly interested in (mu) -invasive tumor forms appearing 10 weeks after the first application because they are potentially amenable to photodynamic therapy.

Andrejevic-Blant, Snezana; Savary, Jean-Francois; Fontolliet, Charlotte; Monnier, Philippe

1994-10-01

210

7, 12 dimethylbenz(a)anthracene(DMBA)-induced "early" Squamous Cell carcinoma in the Golden Syrian hamster: evaluation of an animal model and comparison with "early" forms of human Squamous Cell car  

NASA Astrophysics Data System (ADS)

To improve our knowledge on PDT of human early squamous cell carcinomas of the upper aero-digestive tract and to evaluate new photosensitizers, we have set up the Syrian hamster as an animal model. A 0.5% oily solution of DMBA was applied topically to the left buccal pouch mucosa 3 times weekly. The contralateral buccal pouch served as control. Groups of 5 animals were sacrificed at 6, 8, 10 and 12 weeks from the first applications. Tissue samples of the buccal mucosa were analyzed by histopathologic and immunohistochemical techniques and compared with preneoplastic and neoplastic changes which are seen in the human carcinogenesis of the upper aero-digestive tract. After 6 to 9 weeks from the beginning of the application, we observed different degrees of epithelial dysplasia and after 10 weeks microinvasive carcinomas. The sequence of dysplastic changes to early carcinoma was reproducible in different groups of animals, and they were closely comparable with the human forms of `early' squamous cell cancer. Hyper- and dyskeratosis were present at all stages of tumor development. We are particularly interested in (mu) -invasive tumor forms appearing 10 weeks after the first application because they are potentially amenable to photodynamic therapy.

Andrejevic, Snezana; Savary, Jean-Francois; Fontolliet, Charlotte; Monnier, Philippe

1995-03-01

211

Fuzzy hidden Markov chains segmentation for volume determination and quantitation in PET  

NASA Astrophysics Data System (ADS)

Accurate volume of interest (VOI) estimation in PET is crucial in different oncology applications such as response to therapy evaluation and radiotherapy treatment planning. The objective of our study was to evaluate the performance of the proposed algorithm for automatic lesion volume delineation; namely the fuzzy hidden Markov chains (FHMC), with that of current state of the art in clinical practice threshold based techniques. As the classical hidden Markov chain (HMC) algorithm, FHMC takes into account noise, voxel intensity and spatial correlation, in order to classify a voxel as background or functional VOI. However the novelty of the fuzzy model consists of the inclusion of an estimation of imprecision, which should subsequently lead to a better modelling of the 'fuzzy' nature of the object of interest boundaries in emission tomography data. The performance of the algorithms has been assessed on both simulated and acquired datasets of the IEC phantom, covering a large range of spherical lesion sizes (from 10 to 37 mm), contrast ratios (4:1 and 8:1) and image noise levels. Both lesion activity recovery and VOI determination tasks were assessed in reconstructed images using two different voxel sizes (8 mm3 and 64 mm3). In order to account for both the functional volume location and its size, the concept of % classification errors was introduced in the evaluation of volume segmentation using the simulated datasets. Results reveal that FHMC performs substantially better than the threshold based methodology for functional volume determination or activity concentration recovery considering a contrast ratio of 4:1 and lesion sizes of <28 mm. Furthermore differences between classification and volume estimation errors evaluated were smaller for the segmented volumes provided by the FHMC algorithm. Finally, the performance of the automatic algorithms was less susceptible to image noise levels in comparison to the threshold based techniques. The analysis of both simulated and acquired datasets led to similar results and conclusions as far as the performance of segmentation algorithms under evaluation is concerned.

Hatt, M.; Lamare, F.; Boussion, N.; Turzo, A.; Collet, C.; Salzenstein, F.; Roux, C.; Jarritt, P.; Carson, K.; Cheze-LeRest, C.; Visvikis, D.

2007-07-01

212

Differences in Brainstem Fiber Tract Response to Radiation: A Longitudinal Diffusion Tensor Imaging Study  

SciTech Connect

Purpose: To determine whether radiation-induced changes in white matter tracts are uniform across the brainstem. Methods and Materials: We analyzed serial diffusion tensor imaging data, acquired before radiation therapy and over 48 to 72 months of follow-up, from 42 pediatric patients (age 6-20 years) with medulloblastoma. FSL software (FMRIB, Oxford, UK) was used to calculate fractional anisotropy (FA) and axial, radial, and mean diffusivities. For a consistent identification of volumes of interest (VOIs), the parametric maps of each patient were transformed to a standard brain space (MNI152), on which we identified VOIs including corticospinal tract (CST), medial lemniscus (ML), transverse pontine fiber (TPF), and middle cerebellar peduncle (MCP) at the level of pons. Temporal changes of DTI parameters in VOIs were compared using a linear mixed effect model. Results: Radiation-induced white matter injury was marked by a decline in FA after treatment. The decline was often accompanied by decreased axial diffusivity, increased radial diffusivity, or both. This implied axonal damage and demyelination. We observed that the magnitude of the changes was not always uniform across substructures of the brainstem. Specifically, the changes in DTI parameters for TPF were more pronounced than in other regions (P<.001 for FA) despite similarities in the distribution of dose. We did not find a significant difference among CST, ML, and MCP in these patients (P>.093 for all parameters). Conclusions: Changes in the structural integrity of white matter tracts, assessed by DTI, were not uniform across the brainstem after radiation therapy. These results support a role for tract-based assessment in radiation treatment planning and determination of brainstem tolerance.

Uh, Jinsoo, E-mail: jinsoo.uh@stjude.org [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Merchant, Thomas E. [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Li, Yimei; Feng, Tianshu [Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Gajjar, Amar [Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Ogg, Robert J.; Hua, Chiaho [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)

2013-06-01

213

Fuzzy hidden Markov chains segmentation for volume determination and quantitation in PET  

PubMed Central

Accurate volume of interest (VOI) estimation in PET is crucial in different oncology applications such as response to therapy evaluation and radiotherapy treatment planning. The objective of our study was to evaluate the performance of the proposed algorithm for automatic lesion volume delineation; namely the Fuzzy Hidden Markov Chains (FHMC), with that of current state of the art in clinical practice threshold based techniques. As the classical Hidden Markov Chain (HMC) algorithm, FHMC takes into account noise, voxel’s intensity and spatial correlation, in order to classify a voxel as background or functional VOI. However the novelty of the fuzzy model consists of the inclusion of an estimation of imprecision, which should subsequently lead to a better modelling of the “fuzzy” nature of the object on interest boundaries in emission tomography data. The performance of the algorithms has been assessed on both simulated and acquired datasets of the IEC phantom, covering a large range of spherical lesion sizes (from 10 to 37mm), contrast ratios (4:1 and 8:1) and image noise levels. Both lesion activity recovery and VOI determination tasks were assessed in reconstructed images using two different voxel sizes (8mm3 and 64mm3). In order to account for both the functional volume location and its size, the concept of % classification errors was introduced in the evaluation of volume segmentation using the simulated datasets. Results reveal that FHMC performs substantially better than the threshold based methodology for functional volume determination or activity concentration recovery considering a contrast ratio of 4:1 and lesion sizes of <28mm. Furthermore differences between classification and volume estimation errors evaluated were smaller for the segmented volumes provided by the FHMC algorithm. Finally, the performance of the automatic algorithms was less susceptible to image noise levels in comparison to the threshold based techniques. The analysis of both simulated and acquired datasets led to similar results and conclusions as far as the performance of segmentation algorithms under evaluation is concerned.

Hatt, Mathieu; Lamare, Frederic; Boussion, Nicolas; Roux, Christian; Turzo, Alexandre; Cheze-Lerest, Catherine; Jarritt, Peter; Carson, Kathryn; Salzenstein, Fabien; Collet, Christophe; Visvikis, Dimitris

2007-01-01

214

Correlations between indentation modulus and mineral density in bone-fracture calluses  

PubMed Central

The mechanical properties of a healing bone fracture depend not only on the geometry of the fracture callus but also on the material properties of the callus tissues. Despite the biomechanical importance of callus tissues in restoring mechanical integrity to the injured bone, little is known about the material properties of these tissues and whether these properties can be estimated non-invasively. This study used nanoindentation to quantify the spatial variations in indentation modulus throughout the fracture callus and correlated the measurements of modulus with measurements of tissue mineral density (TMD) obtained from images from micro-computed tomography (µCT). Fracture calluses were harvested from rats 24 days following creation of a full-thickness, transverse osteotomy in the femoral mid-diaphysis. Calluses were imaged using µCT, and the average TMD and the median grayvalue (X-ray attenuation) of five, pre-defined volumes of interest (VOIs) in each callus were computed. Nanoindentation was then performed at multiple, regularly spaced locations across 150 µm-thick, sagittal sections of the calluses. The indentation modulus ranged from 0.51 to 1680 MPa throughout the callus, with the highest moduli in the center of the fracture gap and the lowest in the periphery of the gap (P < 0.05). TMD was also highest in the center of the gap (P < 0.05). An increasing trend in both modulus and TMD was observed in the regions of the callus adjacent to the periosteal surfaces of the cortex. While no correlation was found between the average indentation modulus in a given VOI and the median grayvalue of that VOI, the average indentation modulus and the average TMD were positively correlated (R = 0.70, P < 0.05). Together, these findings establish the spatial heterogeneity in the mechanical behavior of tissues in fracture calluses and indicate that the indentation modulus of these tissues can be estimated by non-invasive measurements of tissue mineralization.

Leong, Pui L.; Morgan, Elise F.

2009-01-01

215

Experimental realization of fluence field modulated CT using digital beam attenuation.  

PubMed

Tailoring CT scan acquisition parameters to individual patients is a topic of much research in the CT imaging community. It is now common place to find automatically adjusted tube current options for modern CT scanners. In addition, the use of beam shaping filters, commonly called bowtie filters, is available on most CT systems and allows for different body regions to receive different incident x-ray fluence distributions. However, no method currently exists which allows for the form of the incident x-ray fluence distribution to change as a function of the view angle. This study represents the first experimental realization of fluence field modulated CT (FFMCT) for a c-arm geometry CT scan. X-ray fluence modulation is accomplished using a digital beam attenuator (DBA). The device is composed of ten iron wedge pairs that modulate the thickness of iron, the x-rays must traverse before reaching a patient. Using this device, experimental data was taken using a Siemens Zeego c-arm scanner. Scans were performed on a cylindrical polyethylene phantom and on two different sections of an anthropomorphic phantom. The DBA was used to equalize the x-ray fluence striking the detector for each scan. Non DBA, or 'flat field' scans were also acquired of the same phantom objects for comparison. In addition, a scan was performed in which the DBA was used to enable volume of interest (VOI) imaging. In VOI, only a small sub-volume within a patient receives full dose and the rest of the patient receives a much lower dose. Data corrections unique to using a piece-wise constant modulator were also developed. The feasibility of FFMCT implemented using a DBA device has been demonstrated. Initial results suggest dose reductions of up to 3.6 times relative to 'flat field' CT. In addition to dose reduction, the DBA enables a large improvement in image noise uniformity and the ability to provide regionally enhanced signal to noise using VOI imaging techniques. The results presented in this paper take the field of FFMCT from the theoretical stage to that of possible clinical implementation. FFMCT, as shown in this paper, can reduce the patient dose while maintaining or improving image quality. In addition, the DBA has been experimentally shown to be well suited to implement entirely new imaging methods like photon counting and VOI imaging. PMID:24556823

Szczykutowicz, T P; Mistretta, C A

2014-03-01

216

Pulmonary nodule registration in serial CT scans based on rib anatomy and nodule template matching  

SciTech Connect

An automated method is being developed in order to identify corresponding nodules in serial thoracic CT scans for interval change analysis. The method uses the rib centerlines as the reference for initial nodule registration. A spatially adaptive rib segmentation method first locates the regions where the ribs join the spine, which define the starting locations for rib tracking. Each rib is tracked and locally segmented by expectation-maximization. The ribs are automatically labeled, and the centerlines are estimated using skeletonization. For a given nodule in the source scan, the closest three ribs are identified. A three-dimensional (3D) rigid affine transformation guided by simplex optimization aligns the centerlines of each of the three rib pairs in the source and target CT volumes. Automatically defined control points along the centerlines of the three ribs in the source scan and the registered ribs in the target scan are used to guide an initial registration using a second 3D rigid affine transformation. A search volume of interest (VOI) is then located in the target scan. Nodule candidate locations within the search VOI are identified as regions with high Hessian responses. The initial registration is refined by searching for the maximum cross-correlation between the nodule template from the source scan and the candidate locations. The method was evaluated on 48 CT scans from 20 patients. Experienced radiologists identified 101 pairs of corresponding nodules. Three metrics were used for performance evaluation. The first metric was the Euclidean distance between the nodule centers identified by the radiologist and the computer registration, the second metric was a volume overlap measure between the nodule VOIs identified by the radiologist and the computer registration, and the third metric was the hit rate, which measures the fraction of nodules whose centroid computed by the computer registration in the target scan falls within the VOI identified by the radiologist. The average Euclidean distance error was 2.7{+-}3.3 mm. Only two pairs had an error larger than 10 mm. The average volume overlap measure was 0.71{+-}0.24. Eighty-three of the 101 pairs had ratios larger than 0.5, and only two pairs had no overlap. The final hit rate was 93/101.

Shi Jiazheng; Sahiner, Berkman; Chan, H.-P.; Hadjiiski, Lubomir; Zhou, C.; Cascade, Philip N.; Bogot, Naama; Kazerooni, Ella A.; Wu, Y.-T.; Wei, J. [Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2007-04-15

217

Correction of segmented lung boundary for inclusion of pleural nodules and pulmonary vessels in chest CT images.  

PubMed

We propose a new curvature-based method for correcting the segmented lung boundary. Our method consists of the following steps. First, the lungs are extracted from chest CT images by the automatic segmentation method. Second, the segmented lung contours are corrected by lung smoothing in each axial slice. Our scan line search provides an efficient contour tracing and curvature calculation. Finally, the smoothed lung contours are corrected by 3D VOI refinement. This increases the smoothness in the z-axis without distortion of the lung boundary. Experimental results show that our method effectively incorporates the pleural nodules and pulmonary vessels into the segmentation results. PMID:18589408

Yim, Yeny; Hong, Helen

2008-08-01

218

The effect of volume-of-interest misregistration on quantitative planar activity and dose estimation  

NASA Astrophysics Data System (ADS)

In targeted radionuclide therapy (TRT), dose estimation is essential for treatment planning and tumor dose response studies. Dose estimates are typically based on a time series of whole-body conjugate view planar or SPECT scans of the patient acquired after administration of a planning dose. Quantifying the activity in the organs from these studies is an essential part of dose estimation. The quantitative planar (QPlanar) processing method involves accurate compensation for image degrading factors and correction for organ and background overlap via the combination of computational models of the image formation process and 3D volumes of interest defining the organs to be quantified. When the organ VOIs are accurately defined, the method intrinsically compensates for attenuation, scatter and partial volume effects, as well as overlap with other organs and the background. However, alignment between the 3D organ volume of interest (VOIs) used in QPlanar processing and the true organ projections in the planar images is required. The aim of this research was to study the effects of VOI misregistration on the accuracy and precision of organ activity estimates obtained using the QPlanar method. In this work, we modeled the degree of residual misregistration that would be expected after an automated registration procedure by randomly misaligning 3D SPECT/CT images, from which the VOI information was derived, and planar images. Mutual information-based image registration was used to align the realistic simulated 3D SPECT images with the 2D planar images. The residual image misregistration was used to simulate realistic levels of misregistration and allow investigation of the effects of misregistration on the accuracy and precision of the QPlanar method. We observed that accurate registration is especially important for small organs or ones with low activity concentrations compared to neighboring organs. In addition, residual misregistration gave rise to a loss of precision in the activity estimates that was on the order of the loss of precision due to Poisson noise in the projection data. These results serve as a lower bound on the effects of misregistration on the accuracy and precision of QPlanar activity estimate and demonstrate that misregistration errors must be taken into account when assessing the overall precision of organ dose estimates.

Song, N.; He, B.; Frey, E. C.

2010-09-01

219

Digital tomosynthesis mammography: intra- and interplane artifact reduction for high-contrast objects on reconstructed slices using a priori 3D geometrical information  

NASA Astrophysics Data System (ADS)

We are developing a computerized technique to reduce intra- and interplane ghosting artifacts caused by high-contrast objects such as dense microcalcifications (MCs) or metal markers on the reconstructed slices of digital tomosynthesis mammography (DTM). In this study, we designed a constrained iterative artifact reduction method based on a priori 3D information of individual MCs. We first segmented individual MCs on projection views (PVs) using an automated MC detection system. The centroid and the contrast profile of the individual MCs in the 3D breast volume were estimated from the backprojection of the segmented individual MCs on high-resolution (0.1 mm isotropic voxel size) reconstructed DTM slices. An isolated volume of interest (VOI) containing one or a few MCs is then modeled as a high-contrast object embedded in a local homogeneous background. A shift-variant 3D impulse response matrix (IRM) of the projection-reconstruction (PR) system for the extracted VOI was calculated using the DTM geometry and the reconstruction algorithm. The PR system for this VOI is characterized by a system of linear equations. A constrained iterative method was used to solve these equations for the effective linear attenuation coefficients (eLACs) within the isolated VOI. Spatial constraint and positivity constraint were used in this method. Finally, the intra- and interplane artifacts on the whole breast volume resulting from the MC were calculated using the corresponding impulse responses and subsequently subtracted from the original reconstructed slices. The performance of our artifact-reduction method was evaluated using a computer-simulated MC phantom, as well as phantom images and patient DTMs obtained with IRB approval. A GE prototype DTM system that acquires 21 PVs in 3º increments over a +/-30º range was used for image acquisition in this study. For the computer-simulated MC phantom, the eLACs can be estimated accurately, thus the interplane artifacts were effectively removed. For MCs in phantom and patient DTMs, our method reduced the artifacts but also created small over-corrected areas in some cases. Potential reasons for this may include: the simplified mathematical modeling of the forward projection process, and the amplified noise in the solution of the system of linear equations.

Ge, Jun; Chan, Heang-Ping; Sahiner, Berkman; Zhang, Yiheng; Wei, Jun; Hadjiiski, Lubomir M.; Zhou, Chuan

2007-03-01

220

Risk estimation and value-of-information analysis for three proposed genetic screening programs for chronic beryllium disease prevention.  

PubMed

Genetic differences (polymorphisms) among members of a population are thought to influence susceptibility to various environmental exposures. In practice, however, this information is rarely incorporated into quantitative risk assessment and risk management. We describe an analytic framework for predicting the risk reduction and value-of-information (VOI) resulting from specific risk management applications of genetic biomarkers, and we apply the framework to the example of occupational chronic beryllium disease (CBD), an immune-mediated pulmonary granulomatous disease. One described Human Leukocyte Antigen gene variant, HLA-DP beta 1*0201, contains a substitution of glutamate for lysine at position 69 that appears to have high sensitivity (approximately 94%) but low specificity (approximately 70%) with respect to CBD among individuals occupationally exposed to respirable beryllium. The expected postintervention CBD prevalence rates for using the genetic variant (1) as a required job placement screen, (2) as a medical screen for semiannual in place of annual lymphocyte proliferation testing, or (3) as a voluntary job placement screen are 0.08%, 0.8%, and 0.6%, respectively, in a hypothetical cohort with 1% baseline CBD prevalence. VOI analysis is used to examine the reduction in total social cost, calculated as the net value of disease reduction and financial expenditures, expected for proposed CBD intervention programs based on the genetic susceptibility test. For the example cohort, the expected net VOI per beryllium worker for genetically based testing and intervention is $13,000, $1,800, and $5,100, respectively, based on a health valuation of $1.45 million per CBD case avoided. VOI results for alternative CBD evaluations are also presented. Despite large parameter uncertainty, probabilistic analysis predicts generally positive utility for each of the three evaluated programs when avoidance of a CBD case is valued at $1 million or higher. Although the utility of a proposed risk management program may be evaluated solely in terms of risk reduction and financial costs, decisions about genetic testing and program implementation must also consider serious social, legal, and ethical factors. PMID:10795342

Bartell, S M; Ponce, R A; Takaro, T K; Zerbe, R O; Omenn, G S; Faustman, E M

2000-02-01

221

When is enough evidence enough? - Using systematic decision analysis and value-of-information analysis to determine the need for further evidence.  

PubMed

Decision analysis (DA) and value-of-information (VOI) analysis provide a systematic, quantitative methodological framework that explicitly considers the uncertainty surrounding the currently available evidence to guide healthcare decisions. In medical decision making under uncertainty, there are two fundamental questions: 1) What decision should be made now given the best available evidence (and its uncertainty)?; 2) Subsequent to the current decision and given the magnitude of the remaining uncertainty, should we gather further evidence (i.e., perform additional studies), and if yes, which studies should be undertaken (e.g., efficacy, side effects, quality of life, costs), and what sample sizes are needed? Using the currently best available evidence, VoI analysis focuses on the likelihood of making a wrong decision if the new intervention is adopted. The value of performing further studies and gathering additional evidence is based on the extent to which the additional information will reduce this uncertainty. A quantitative framework allows for the valuation of the additional information that is generated by further research, and considers the decision maker's objectives and resource constraints. Claxton et al. summarise: "Value of information analysis can be used to inform a range of policy questions including whether a new technology should be approved based on existing evidence, whether it should be approved but additional research conducted or whether approval should be withheld until the additional evidence becomes available." [Claxton K. Value of information entry in Encyclopaedia of Health Economics, Elsevier, forthcoming 2014.] The purpose of this tutorial is to introduce the framework of systematic VoI analysis to guide further research. In our tutorial article, we explain the theoretical foundations and practical methods of decision analysis and value-of-information analysis. To illustrate, we use a simple case example of a foot ulcer (e.g., with diabetes) as well as key references from the literature, including examples for the use of the decision-analytic VoI framework by health technology assessment agencies to guide further research. These concepts may guide stakeholders involved or interested in how to determine whether or not and, if so, which additional evidence is needed to make decisions. PMID:24315327

Siebert, Uwe; Rochau, Ursula; Claxton, Karl

2013-01-01

222

ESA's Venus Express to reach final destination  

NASA Astrophysics Data System (ADS)

First step: catching Venus To begin to explore our Earth’s hot and hazy sister planet, Venus Express must complete a critical first step, the most challenging one following launch. This involves a set of complex operations and manoeuvres that will inject the spacecraft into orbit. The Venus Orbit Insertion (VOI) manoeuvre allows the spacecraft to reduce its speed relative to Venus, so that it can be captured by the planet’s gravitation. The manoeuvre is a critical one which must proceed at precisely the right place and time. The VOI phase officially started on 4 April and will not be completed until 13 April. It is split into three main sub-phases. The first consists in preparing or initialising the spacecraft for the actual capture manoeuvre so as to avoid the risk of the spacecraft going into safe mode, should parameters unrelated to VOI go off-range. The capture manoeuvre itself consists of a main-engine burn lasting about 50 minutes on the morning of 11 April starting at 09:17 (Central European Summer Time). This is the second main VOI sub-phase. The final sub-phase will be restoring all spacecraft functions, notably resuming communications with Earth and uplinking the commands to be executed during the preliminary ‘capture’ orbit. Orbital capture is controlled by an automatic sequence of predefined commands, uploaded to the spacecraft four days prior to VOI. This sequence is the minimum set needed to perform the main-engine burn. All spacecraft operations are controlled and commanded by the ground control team located at ESA’s European Spacecraft Operations Centre (ESOC) in Darmstadt, Germany. Timeeline of major VOI events (some times subject to change) 4 Aprilacecraft transmitter connected to low gain antenna is switched on. During its interplanetary cruise and during the scientific part of the mission to come, Venus Express communicates with Earth by means of its two high gain antennas. However, during the orbit capture phase (11 April), these two antennas become unusable because of the spacecraft’s required orientation at that time. The low gain antenna, carrying a feeble but instantly recognisable signal, will be transmitting throughout all VOI manoeuvres. This will allow ground controllers to monitor the velocity change during the burn, using NASA’s Deep Space Network’s 70-metre antenna near Madrid, Spain. No other means of communication with the Earth is possible during the capture burn. 5 and 9 April, targeting control manoeuvres. Two time slots are available to adjust course if needed. Given the high accuracy of the course correction performed end of March, Venus Express is currently on the right trajectory for a successful capture into orbit and it is therefore unlikely that either of these two extra slots will be required. 10 to 11 April, final preparations for VOI manoeuvre. 24 to 12 hours before VOI, spacecraft controllers will command Venus Express into its final configuration for the burn. Over the final 12 hours, they will monitor its status, ready to deal with any contingencies requiring last-minute trajectory correction or any revising of the main-engine burn duration. 11 April, 08:03 (CEST), ‘slew’ manoeuvre. This manoeuvre lasts about half an hour and rotates Venus Express so that the main engine faces the direction of motion. Thanks to this, the burn will slow down (rather than accelerate) the spacecraft. 11 April, 09:17 (CEST), main-engine burn starts. A few minutes after firing of the spacecraft thrusters to make sure the propellant settles in the feed lines to the main engine, the latter will begin its 50-minute long burn, ending at 10:07. This thrust will reduce the initial velocity of 29 000 kilometres per hour (in relation to Venus) by 15 percent, allowing capture. Venus Express will settle into its preliminary, elongated nine-day orbit. On capture, it will be at about 120 million kilometres from the Earth and, at its nearest point, within 400 km of the surface of Venus. During the burn, at 09:45 (CEST), Venus Express will disappear behind the planet and will not be visi

2006-04-01

223

Automated volume of interest delineation and rendering of cone beam CT images in interventional cardiology  

NASA Astrophysics Data System (ADS)

Interventional C-arm systems allow the efficient acquisition of 3D cone beam CT images. They can be used for intervention planning, navigation, and outcome assessment. We present a fast and completely automated volume of interest (VOI) delineation for cardiac interventions, covering the whole visceral cavity including mediastinum and lungs but leaving out rib-cage and spine. The problem is addressed in a model based approach. The procedure has been evaluated on 22 patient cases and achieves an average surface error below 2mm. The method is able to cope with varying image intensities, varying truncations due to the limited reconstruction volume, and partially with heavy metal and motion artifacts.

Lorenz, Cristian; Schäfer, Dirk; Eshuis, Peter; Carroll, John; Grass, Michael

2012-02-01

224

Structure crustale et anomalies du champ de gravite dans l'est du Canada  

NASA Astrophysics Data System (ADS)

Cette these presente les resultats d'etudes gravimetriques menees dans le Bouclier canadien. Les mesures du champ de gravite recoltees le long et a proximite de divers transects Lithoprobe y sont interpretees. Chacun des chapitres de cette these est un article publie ou soumis. Le premier article presente l'interpretation gravimetrique le long de la ligne sismique 52 de Lithoprobe, dans la province de Grenville. A l'echelle regionale, la modelisation de l'anomalie de Bouguer invoque un amincissement crustal au sud du front de Grenville sous le terrane allochtone du reservoir Cabonga. Cet amincissement, localise au niveau de la croute inferieure, peut etre associe a une extension post-orogenique. Le modele gravimetrique a aussi permis de mettre en evidence des caracteristiques majeures non revelees par les donnees sismiques, telle que la zone de contact subverticale entre les terranes du reservoir de Cabonga et du reservoir Dozois. La rampe de Baskatong representerait une discontinuite majeure le long de laquelle, les terranes proterozoiques furent accretes. Par ailleurs, un modele de l'anomalie residuelle, dans la partie nord du profil, met en evidence trois corps gabbroiques peu profonds. Le second article presente des modeles crustaux du nord de la province du Superieur a la lumiere de nouvelles donnees de gravite recoltees le long d'un transect traversant les sous-provinces de Nemiscau et La Grande. L'interpretation de l'anomalie de Bouguer pour le nord de l'Abitibi et l'Opatica, invoque un epaississement crustal. Pour les sous-provinces de Nemiscau et La Grande, l'interpretation gravimetrique invoque une densite de la croute superieure plus elevee qu'en Abitibi et en Opatica. Un leger epaississement crustal est observe dans la sous-province de La Grande. Des sequences supracrustales mafiques sont aussi mises en evidence a l'extremite nord du profil dans la sous-province de La Grande. La signature gravimetrique associee a la variation laterale de densite et les evidences de terrain indiquent un pendage vers le nord des principales frontieres tectoniques. Le troisieme chapitre fait l'objet d'une etude du champ de pesanteur au dessus de la region de la baie d'Ungava a partir de donnees satellite et de nouvelles donnees recoltees le long de la cote sud de la baie. Un leve gravimetrique partant de la baie aux Feuilles, dans la province du Superieur, traversant l'Orogene du Nouveau Quebec (ONQ), et finissant pres de la riviere George dans le craton de Rae, a ete realise. L'interpretation des donnees acquises a permis de fournir des modeles de densite. Ces modeles mettent en evidence un epaississement crustal sous l'ONQ et un amincissement sous le terrane de Kuujjuaq, a l'est de l'orogene. Alors que plus a l'est, dans le craton de Rae, une anomalie negative de quelques dix milligals est correlee avec les extensions vers le nord de la zone de cisaillement de la riviere George (ZCRG) et du batholite de De Pas. L'orientation des structures sur les modeles de gravite suggere un chevauchement du craton de Rae au dessus de l'ONQ. (Abstract shortened by UMI.)

Telmat, Hamid

225

Conception d'un circuit d'etouffement pour photodiodes a avalanche en mode geiger pour integration heterogene 3d  

NASA Astrophysics Data System (ADS)

Le Groupe de Recherche en Appareillage Medical de Sherbrooke (GRAMS) travaille actuellement sur un programme de recherche portant sur des photodiodes a avalanche mono-photoniques (PAMP) operees en mode Geiger en vue d'une application a la tomographie d'emission par positrons (TEP). Pour operer dans ce mode; la PAMP, ou SPAD selon l'acronyme anglais (Single Photon Avalanche Diode), requiert un circuit d'etouffement (CE) pour, d'une part, arreter l'avalanche pouvant causer sa destruction et, d'autre part. la reinitialiser en mode d'attente d'un nouveau photon. Le role de ce CE comprend egalement une electronique de communication vers les etages de traitement avance de signaux. La performance temporelle optimale du CE est realisee lorsqu'il est juxtapose a la PAMP. Cependant, cela entraine une reduction de la surface photosensible ; un element crucial en imagerie. L'integration 3D, a base d'interconnexions verticales, offre une solution elegante et performante a cette problematique par l'empilement de circuits integres possedant differentes fonctions (PAMP, CE et traitement avance de signaux). Dans l'approche proposee, des circuits d'etouffement de 50 pm x 50 pm realises sur une technologie CMOS 130 mn 3D Tezzaron, contenant chacun 112 transistors, sont matrices afin de correspondre a une matrice de PAMP localisee sur une couche electronique superieure. Chaque circuit d'etouffement possede une gigue temporelle de 7,47 ps RMS selon des simulations faites avec le logiciel Cadence. Le CE a la flexibilite d'ajuster les temps d'etouffement et de recharge pour la PAMP tout en presentant une faible consommation de puissance (~ 0,33 mW a 33 Mcps). La conception du PAMP necessite de supporter des tensions superieures aux 3,3 V de la technologie. Pour repondre a ce probleme, des transistors a drain etendu (DEMOS) ont ete realises. En raison de retards de production par Ies fabricants, les circuits n'ont pu etre testes physiquement par des mesures. Les resultats de ce memoire sont par consequent bases sur des resultats de simulations avec le logiciel Cadence. Mots-cles : Circuit d'etouffement, Photodiodes a avalanche monophotoniques (PAMP), Single Photon Avalanche Diode (SPAD), Integration 3D heterogene, Drain-Extended MOS (DEMOS), CMOS 130 nm 3D Tezzaron/Chartered, Tomographie d'emission par positrons (TEP)

Boisvert, Alexandre

226

Elaboration d'un dosimetre a fibres scintillantes  

NASA Astrophysics Data System (ADS)

Le but de ce travail est de developper un dosimetre constitue d'une matrice de petits scintillateurs plastiques. Ce dosimetre doit presenter une bonne precision et reproductibilite pour satisfaire aux exigences imposees par des techniques de radiotherapie de pointe comme la radiotherapie d'intensite modulee, la radiochirurgie et la tomotherapie. Le desavantage majeur de cette forme de dosimetrie est la presence de bruit produit par l'effet de la radiation sur la fibre optique transportant la lumiere de scintillation jusqu'au photodetecteur. Pour en reduire l'impact, une etude approfondie des dosimetres a scintillation a ete effectuee. Commencant par une modelisation theorique de la collecte et du guidage lumineux, ce travail a ete suivi d'une comparaison experimentale de plusieurs scintillateurs plastiques, de methodes de couplage, de photodetecteurs et de techniques de filtrage. Ces etudes ont permis de choisir les fibres scintillantes pour leur gain de signal de 50% relativement aux autres scintillateurs plastiques. La camera CCD est le photodetecteur le plus adapte pour ce projet etant donne une sensibilite et une stabilite suffisantes, une capacite d'evaluer 3000 signaux dosimetriques simultanement et un systeme de separation chromatique. Apres la selection des meilleures composantes, un dosimetre a ete developpe pour etudier la performance des techniques de filtrage. Il a ete demontre que, apres utilisation du meilleur filtrage, une precision superieure a 1% pouvait etre atteinte. Un dosimetre a trois detecteurs de volumes differents (0,0014, 0,0034 et 0,0083 cm 3) a demontre une linearite face a des taux de doses allant de 10 a 600 cGy/min et pour des temps d'integration entre 0,05 et 50 s. Une reproductibilite superieure a 1% a ete observee pour des doses minimales de 45, 35 et 20 cGy respectivement pour le petit, le moyen et le grand detecteur. Une matrice de 10 detecteurs espaces de 5 mm sur une ligne a ensuite ete realisee. Ce dosimetre s'est montre adapte pour l'evaluation precise et rapide de patrons de doses. Meme si un modele abordable de camera CCD a ete utilise, il a ete possible de developper un dosimetre precis, reproductible et de haute resolution spatiale possedant les excellentes proprietes des scintillateurs plastiques.

Archambault, Louis

227

Le changement comme tradition dans la recherche et la formation a la recherche en biotechnologie et en peripherie Etude de cas en sciences de la sante, sciences naturelles et genie  

NASA Astrophysics Data System (ADS)

Le champ de la recherche scientifique et de la formation a la recherche est traverse depuis quelques dizaines d'annees par plusieurs courants et discours associes au changement, mais peu de travaux empiriques permettent de comprendre ce qui change concretement. C'est la contribution originale de cette these au champ de l'education, plus specifiquement a l'etude sociologique de l'enseignement superieur ou sont concentrees les activites liees a la triade thematique du programme doctoral dans lequel elle a ete produite : recherche, formation et pratique. L'enquete-terrain a ete realisee en 2009 et 2010 aupres de 808 repondants affilies a 60 etablissements au Quebec et a produit un vaste materiau de nature mixte (donnees quantitatives et qualitatives). Un portrait de la nebuleuse biotechnologique qui touche les secteurs des sciences de la sante, des sciences naturelles et du genie a ete realise. Ce domaine concerne des dizaines de disciplines et se revele de nature transdisciplinaire, mais les pratiques n'y sont pas davantage marquees par le changement que celles d'autres domaines connexes. Les dynamiques sociales ont fait l'objet d'analyses comparatives dans quatre contextes: le choix des programmes, des objets et des methodes, le financement, la diffusion et la planification de la carriere. Les resultats indiquent que les echanges entre les agents traditionnellement situes au coeur des activites de recherche dominent ces dynamiques dans tous les contextes etudies. L'etude des representations au fondement des pratiques a revele l'existence de trois ecoles de pensee qui coexistent dans le champ scientifique: academique, pragmatique et economiste. Ces ecoles permettent de categoriser les agents en fonction des zones de fractures qui marquent leurs oppositions tout en identifiant ce qu'ils ont en commun. Les representations et les pratiques liees a la formation temoignent d'un habitus plutot homogene, alors que les contradictions semblent plus souvent ancrees dans des luttes universitaires que scientifiques, concentrees sur la negociation du capital scientifique, symbolique et economique en jeu dans la formation doctorale, dans les carrieres auxquelles elle mene, et dans les qualites du titre de Ph.D. Au final, la confusion entre des logiques opposees peut etre reduite en reinterpretant le changement comme tradition du champ scientifique. Mots-cles Sociologie, education, enseignement superieur, science et technologie, biotechnologie, formation doctorale, champ scientifique, reseaux sociaux

Bourque, Claude Julie

228

Effects of Metformin on the Cerebral Metabolic Changes in Type 2 Diabetic Patients  

PubMed Central

Metformin, a widely used antidiabetic drug, has numerous effects on human metabolism. Based on emerging cellular, animal, and epidemiological studies, we hypothesized that metformin leads to cerebral metabolic changes in diabetic patients. To explore metabolism-influenced foci of brain, we used 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography for type 2 diabetic patients taking metformin (MET, n = 18), withdrawing from metformin (wdMET, n = 13), and not taking metformin (noMET, n = 9). Compared with the noMET group, statistical parametric mapping showed that the MET group had clusters with significantly higher metabolism in right temporal, right frontal, and left occipital lobe white matter and lower metabolism in the left parahippocampal gyrus, left fusiform gyrus, and ventromedial prefrontal cortex. In volume of interest (VOI-) based group comparisons, the normalized FDG uptake values of both hypermetabolic and hypometabolic clusters were significantly different between groups. The VOI-based correlation analysis across the MET and wdMET groups showed a significant negative correlation between normalized FDG uptake values of hypermetabolic clusters and metformin withdrawal durations and a positive but nonsignificant correlation in the turn of hypometabolic clusters. Conclusively, metformin affects cerebral metabolism in some white matter and semantic memory related sites in patients with type 2 diabetes.

Huang, Yung-Cheng; Hsu, Chien-Chin; Lin, Wei-Che; Yin, Tang-Kai; Huang, Chi-Wei; Wang, Pei-Wen; Chang, Han-Hsuan

2014-01-01

229

Assessing the value of information for long-term structural health monitoring  

NASA Astrophysics Data System (ADS)

In the field of Structural Health Monitoring, tests and sensing systems are intended as tools providing diagnoses, which allow the operator of the facility to develop an efficient maintenance plan or to require extraordinary measures on a structure. The effectiveness of these systems depends directly on their capability to guide towards the most optimal decision for the prevailing circumstances, avoiding mistakes and wastes of resources. Though this is well known, most studies only address the accuracy of the information gained from sensors without discussing economic criteria. Other studies evaluate these criteria separately, with only marginal or heuristic connection with the outcomes of the monitoring system. The concept of "Value of Information" (VoI) provides a rational basis to rank measuring systems according to a utility-based metric, which fully includes the decision-making process affected by the monitoring campaign. This framework allows, for example, an explicit assessment of the economical justifiability of adopting a sensor depending on its precision. In this paper we outline the framework for assessing the VoI, as applicable to the ranking of competitive measuring systems. We present the basic concepts involved, highlight issues related to monitoring of civil structures, address the problem of non-linearity of the cost-to-utility mapping, and introduce an approximate Monte Carlo approach suitable for the implementation of time-consuming predictive models.

Pozzi, Matteo; der Kiureghian, Armen

2011-03-01

230

Optimising the reward of appraisal drilling  

SciTech Connect

Management of the uncertainties associated with the development of a hydrocarbon resource is essential to minimize economic risk. In many instances these uncertainties can only be reduced by appraisal drilling. This presentation illustrates the efforts being made to manage uncertainty by determining its impact on overall project profitability. The Value of Information (VOI) approach is described. VOI aims at quantifying the benefits of appraisal by determining its economic reward in terms of its contribution to a development plan which is economically robust over the uncertainty range. Appraisal drilling costs can be reduced by combining appraisal and development objectives in one well. The growing use of horizontal drilling technology has resulted in novel approaches to appraisal. As examples, in the Osprey and Brent Fields (UK North Sea) wells were designed to satisfy both appraisal and development objectives. In Osprey, a well was drilled from a central production platform to provide water injection support in a satellite structure while at the same time appraising the saddle area between the two structures. In Brent, horizontal wells are used to appraise and develop the so called slump blocks, characterized by being highly faulted and compartmentalized. Another increasingly common application of horizontal wells is for the flank appraisal of hydrocarbon bearing structure. Examples from the Rabi Field (Gabon) and Batan Field (Nigeria) show how appraisal was achieved by extending the reach of horizontal development wells from the central core of the structures.

Gdula, J.

1996-01-01

231

Correlation between serotonin synthesis and 5-HT1A receptor binding in the living human brain: a combined alpha-[11C]MT and [18F]MPPF positron emission tomography study.  

PubMed

Serotonin (5-HT) is one of the major neurotransmitters and has been implicated in a wide variety of cerebral functions. Several lines of evidence indicate that 5HT(1A) receptors exert a negative feedback in the synthesis and release of serotonin. While most of what is known about serotonin comes from studies in animals, much less empirical evidence exists about the serotonergic system in the living human brain. This study aims to assess the correlation between serotonin synthesis and 5-HT(1A) receptor binding using positron emission tomography (PET) in humans. Six healthy male volunteers underwent 2 PET scans in the same day: one measuring alpha-[(11)C]MT K [ml/g/min] trapping constant (a measure of serotonin synthesis) and one measuring 5-HT(1A) receptor binding potential BP(ND) with [(18)F]MPPF. Volumes of interest (VOIs) selected a priori included: anterior cingulate cortex (ACC), anterior insula, hippocampus, amygdala, thalamus, hypothalamus and midbrain raphe nuclei. Correlation analyses were conducted voxel-by-voxel and with manually traced VOIs. A significant negative correlation between serotonin synthesis and 5-HT(1A) binding potential was found bilaterally in hippocampus and anterior insula and in the left ACC. The combination of [(18)F]MPPF and alpha-[(11)C]MT PET offers a means to investigate key determinants of 5-HT neurotransmission under physiological and psychopathological conditions in the human brain in vivo. PMID:18583156

Frey, Benicio N; Rosa-Neto, Pedro; Lubarsky, Stuart; Diksic, Mirko

2008-08-15

232

The Value of Information from a GRACE-Enhanced Drought Severity Index  

NASA Astrophysics Data System (ADS)

Water storage anomalies derived from the Gravity Recovery and Climate Experiment Data Assimilation System (GRACE-DAS) have been used to enhance the information contained in drought indicators. The potential value of this information is to inform local and regional decisions to improve economic welfare in the face of drought. Based on a characterization of current drought evaluations, a modeling framework has been structured to analyze the contributed value of the Earth observations in the assessment of the onset and duration of droughts and their regional impacts. The analysis focuses on (1) characterizing how GRACE-DAS provides Earth observation information for a drought warning, (2) assessing how a GRACE-DAS-enhanced U.S. Drought Monitor would improve economic outcomes in a region, and (3) applying this enhancement process in a decision framework to illustrate the potential role of GRACE data products in a recent drought and response scenario for a value-of-information (VOI) analysis. The VOI analysis quantifies the relative contribution of enhanced understanding and communication of the societal benefits associated with GRACE Earth observation science. Our emphasis is to illustrate the role of an enhanced National Integrated Drought Information System outlook on three key societal outcomes: effects on particular economic sectors, changes in land management decisions, and reductions in damages to ecosystem services.

Kuwayama, Y.; Bernknopf, R.; Macauley, M.; Brookshire, D.; Zaitchik, B. F.; Rodell, M.

2013-12-01

233

Predicting the biomechanical strength of proximal femur specimens with Minkowski functionals and support vector regression  

NASA Astrophysics Data System (ADS)

Regional trabecular bone quality estimation for purposes of femoral bone strength prediction is important for improving the clinical assessment of osteoporotic fracture risk. In this study, we explore the ability of 3D Minkowski Functionals derived from multi-detector computed tomography (MDCT) images of proximal femur specimens in predicting their corresponding biomechanical strength. MDCT scans were acquired for 50 proximal femur specimens harvested from human cadavers. An automated volume of interest (VOI)-fitting algorithm was used to define a consistent volume in the femoral head of each specimen. In these VOIs, the trabecular bone micro-architecture was characterized by statistical moments of its BMD distribution and by topological features derived from Minkowski Functionals. A linear multiregression analysis and a support vector regression (SVR) algorithm with a linear kernel were used to predict the failure load (FL) from the feature sets; the predicted FL was compared to the true FL determined through biomechanical testing. The prediction performance was measured by the root mean square error (RMSE) for each feature set. The best prediction result was obtained from the Minkowski Functional surface used in combination with SVR, which had the lowest prediction error (RMSE = 0.939 ± 0.345) and which was significantly lower than mean BMD (RMSE = 1.075 ± 0.279, p<0.005). Our results indicate that the biomechanical strength prediction can be significantly improved in proximal femur specimens with Minkowski Functionals extracted from on MDCT images used in conjunction with support vector regression.

Yang, Chien-Chun; Nagarajan, Mahesh B.; Huber, Markus B.; Carballido-Gamio, Julio; Bauer, Jan S.; Baum, Thomas; Eckstein, Felix; Lochmüller, Eva-Maria; Link, Thomas M.; Wismüller, Axel

2014-03-01

234

Estimating the benefits of land imagery in environmental applications: a case study in nonpoint source pollution of groundwater  

USGS Publications Warehouse

Moderate-resolution land imagery (MRLI) is crucial to a more complete assessment of the cumulative, landscape-level effect of agricultural land use and land cover on environmental quality. If this improved assessment yields a net social benefit, then that benefit reflects the value of information (VOI) from MRLI. Environmental quality and the capacity to provide ecosystem services evolve because of human actions, changing natural conditions, and their interaction with natural physical processes. The human actions, in turn, are constrained and redirected by many institutions and regulations such as agricultural, energy, and environmental policies. We present a general framework for bringing together sociologic, biologic, physical, hydrologic, and geologic processes at meaningful scales to interpret environmental implications of MRLI applications. We set out a specific application using MRLI observations to identify crop planting patterns and thus estimate surface management activities that influence groundwater resources over a regional landscape. We tailor the application to the characteristics of nonpoint source groundwater pollution hazards in Iowa to illustrate a general framework in a land use-hydrologic-economic system. In the example, MRLI VOI derives from reducing the risk of both losses to agricultural production and damage to human health and other consequences of contaminated groundwater.

Bernknopf, Richard L.; Forney, William M.; Raunikar, Ronald P.; Mishra, Shruti K.

2012-01-01

235

Using anisotropic 3D Minkowski functionals for trabecular bone characterization and biomechanical strength prediction in proximal femur specimens  

NASA Astrophysics Data System (ADS)

The ability of Anisotropic Minkowski Functionals (AMFs) to capture local anisotropy while evaluating topological properties of the underlying gray-level structures has been previously demonstrated. We evaluate the ability of this approach to characterize local structure properties of trabecular bone micro-architecture in ex vivo proximal femur specimens, as visualized on multi-detector CT, for purposes of biomechanical bone strength prediction. To this end, volumetric AMFs were computed locally for each voxel of volumes of interest (VOI) extracted from the femoral head of 146 specimens. The local anisotropy captured by such AMFs was quantified using a fractional anisotropy measure; the magnitude and direction of anisotropy at every pixel was stored in histograms that served as a feature vectors that characterized the VOIs. A linear multi-regression analysis algorithm was used to predict the failure load (FL) from the feature sets; the predicted FL was compared to the true FL determined through biomechanical testing. The prediction performance was measured by the root mean square error (RMSE) for each feature set. The best prediction performance was obtained from the fractional anisotropy histogram of AMF Euler Characteristic (RMSE = 1.01 ± 0.13), which was significantly better than MDCT-derived mean BMD (RMSE = 1.12 ± 0.16, p<0.05). We conclude that such anisotropic Minkowski Functionals can capture valuable information regarding regional trabecular bone quality and contribute to improved bone strength prediction, which is important for improving the clinical assessment of osteoporotic fracture risk.

Nagarajan, Mahesh B.; De, Titas; Lochmüller, Eva-Maria; Eckstein, Felix; Wismüller, Axel

2014-04-01

236

Narrow-band imaging: a new tool for evaluation of head and neck squamous cell carcinomas. Review of the literature  

PubMed Central

Summary Head and neck squamous cell carcinoma of the upper aerodigestive tract is well known for its frequently late presentation and diagnosis at an advanced stage. In addition, it is well recognized that it may arise in multiple sites, either synchronously or metachronously. Thus it should be imperative to endoscopically screen the upper aerodigestive tract of patients at risk for head and neck squamous cell carcinoma with a new diagnostic tool, especially due to the fact that early lesions are very difficult to detect even by multiple passes with a standard endoscopy, if they are ? 1 cm in diameter. Lugol chromoendoscopy, which is mainly used in the oesophagus, is not suitable for the head and neck region due to severe mucosal irritation. Herein, narrow-band imaging is described, a diagnostic tool already proved as a useful screening method in other endoscopic fields, and its application in the early detection of head and neck squamous cell carcinoma is reviewed, as reported by previous studies in the otolaryngologic literature. Narrow-band imaging relies on the principle of depth of penetration of light, with the narrow-band blue light having a short wavelength (415 nm) penetrating into the mucosa and highlighting the superficial vasculature. Furthermore, the blue filter is designed to correspond to the peak absorption spectrum of haemoglobin to enhance the image of capillary vessels on surface mucosa. Thus, superficial mucosal lesions that would be missed by regular white light endoscopy, are identified, in view of their neoangiogenetic pattern of vasculature, using the blue light of the narrow-band imaging. Narrow-band imaging has been used extensively in the lower aerodigestive system, yet there are only 2 reports of applications in the region of the head and neck, specifically the oropharynx and the hypopharynx. However, these are not the only sites that can benefit from narrow-band imaging. Herewith, the uses and importance are highlighted of narrow-band imaging as a future diagnostic tool in otolaryngology, in the pre-, intra- and post-operative settings.

Piazza, C; Dessouky, O; Peretti, G; Cocco, D; De Benedetto, L; Nicolai, P

2008-01-01

237

Probability distribution of financial returns in a model of multiplicative Brownian motion with stochastic diffusion coefficient  

NASA Astrophysics Data System (ADS)

It is well-known that the mathematical theory of Brownian motion was first developed in the Ph. D. thesis of Louis Bachelier for the French stock market before Einstein [1]. In Ref. [2] we studied the so-called Heston model, where the stock-price dynamics is governed by multiplicative Brownian motion with stochastic diffusion coefficient. We solved the corresponding Fokker-Planck equation exactly and found an analytic formula for the time-dependent probability distribution of stock price changes (returns). The formula interpolates between the exponential (tent-shaped) distribution for short time lags and the Gaussian (parabolic) distribution for long time lags. The theoretical formula agrees very well with the actual stock-market data ranging from the Dow-Jones index [2] to individual companies [3], such as Microsoft, Intel, etc. [] [1] Louis Bachelier, ``Th'eorie de la sp'eculation,'' Annales Scientifiques de l''Ecole Normale Sup'erieure, III-17:21-86 (1900).[] [2] A. A. Dragulescu and V. M. Yakovenko, ``Probability distribution of returns in the Heston model with stochastic volatility,'' Quantitative Finance 2, 443--453 (2002); Erratum 3, C15 (2003). [cond-mat/0203046] [] [3] A. C. Silva, R. E. Prange, and V. M. Yakovenko, ``Exponential distribution of financial returns at mesoscopic time lags: a new stylized fact,'' Physica A 344, 227--235 (2004). [cond-mat/0401225

Silva, Antonio

2005-03-01

238

Melange a Quatre Ondes Degenere dans les Absorbants Saturables EN Milieu Mince  

NASA Astrophysics Data System (ADS)

Le melange a quatre ondes est utilise notamment pour determiner la duree des temps de reorientation moleculaire et mesurer la grandeur des susceptibilites nonlineaires du troisieme ordre. Nous avons mis en evidence les particularites du melange a quatre ondes degenere en milieu absorbant mince a l'aide du formalisme de l'optique nonlineaire et de l'approche holographique. Des experiences realisees avec des impulsions de 33 ps ont permis de caracteriser la cinetique de la nonlinearite en regime transitoire des molecules de rhodamine 6G incorporees dans des matrices d'alcool polyvinylique; un milieu aussi compose d'absorbants anisotropes, les molecules de rhodamine 6G en solution aqueuse et un autre forme d'absorbants isotropes, les films minces de cristaux de semiconducteur CdS_ {x}Se_{1-x} ont ete etudies. Nous avons observe pour ces trois milieux les signaux generes aux ordres superieurs par melange a quatre ondes degenere en milieu mince pour differentes conditions de polarisation.

O'Neill, Claire

1995-01-01

239

Proprietes de Transport Electronique DU Rutile Stoechiometrique  

NASA Astrophysics Data System (ADS)

Le rutile est un oxyde metallique qui presente beaucoup de similitudes avec certains perovskites notamment le titanate de barium ou de strontium. Il est comme ces derniers, compose d'un agencement d'octaedres d'oxygene centres sur l'atome de titane. Ces octaedres sont responsables de la forte polarisabilite de ces cristaux et de leur grande constante dielectrique. Leurs proprietes optiques, seuil d'absorption et spectre de phonons, sont par exemple forts semblables. La presente etude vise a determiner la nature du transport electronique dans le rutile stoechiometrique pur et d'en comparer les resultats avec les proprietes de certains perovskites. Nous determinerons par differentes mesures optoelectroniques les parametres caracteristiques des pieges et leur influence sur le transport des electrons et des trous. Les resultats de conductivite et de capacitance de meme que les spectres de photoconductivite dans nos echantillons ont mis en evidence la presence d'au moins cinq niveaux energetiques dans la bande interdite du rutile agissant comme pieges pour les electrons ou pour les trous et qui jouent un role de premiere importance dans le comportement electrique du rutile. Par la technique de charge transitoire, nous determinerons pour la premiere fois dans le rutile stoechiometrique la grandeur de la mobilite de derive des trous a la temperature ambiante soit 3,4 cm^2/V cdots et nous etablierons une borne superieure a la mobilite des electrons soit 0,1 cm^2 /Vcdots.

Keroack, Danielle

240

Laryngeal cancer: diagnosis and preoperative work-up.  

PubMed

Laryngeal carcinoma is the eleventh-most common form of cancer among men worldwide and is the second-most common malignancy of the head and neck. The primary functions of the larynx involve phonation, respiration, and deglutition but it also contributes to taste and smell by allowing the movement of air over the special sense organs. Thus, loss of laryngeal function affects speech and swallowing and some of the senses that allow us to enjoy the world. Moreover, total laryngectomy bypasses the critical humidification function of the upper aerodigestive tract that renders pulmonary toiletry problematic for these patients. With relatively little change in mortality since the 1970s, recent research has focused not only on improving survival but on laryngeal preservation modalities. PMID:18570953

Chu, Eugene A; Kim, Young J

2008-08-01

241

Alcohol consumption and prostate cancer: a mini review.  

PubMed

Prostate cancer has become a major public health problem worldwide although the etiology of prostate cancer remains largely unknown. Dietary factors, dietary supplements, and physical activity might be important in the prevention of the disease. In the majority of studies published, it was observed that high consumption of meat, alcohol and dairy products has been linked to a greater risk. Specifically, alcohol use, and particularly heavy use, may cause cancers of liver, esophagus, larynx, pharynx and oral cavity, with risks for the aero-digestive cancers. Moderate use among women has been related with increases in breast cancer. Alcohol consumption is a modifiable lifestyle factor that may affect prostate cancer risk. Alcohol alters the hormonal environment and in parallel, containing chemical substances such as flavonoids (red wine), may alter tumor cell growth. In this mini review, the relation between alcohol consumption and prostate cancer risk is analyzed. PMID:20693964

Rizos, Ch; Papassava, M; Golias, Ch; Charalabopoulos, K

2010-07-01

242

Pathogenesis and therapeutic intervention of oral submucous fibrosis  

PubMed Central

Oral submucous fibrosis (OSF) is a chronic, progressive, potentially malignant condition affecting the oral cavity and frequently involving the upper part of the aerodigestive tract including the oropharynx and the upper part of the esophagus. It is characterized by juxtaepithelial inflammatory reaction and progressive fibrosis of lamina propria, leading to stiffening of the oral mucosa eventually causing trismus. This condition is associated with significant morbidity and high risk of malignancy. Over the years, several drugs and combinations have been tried for the treatment of submucous fibrosis, but with limited success, because of its unclear molecular pathogenesis. Till date, there are no known effective treatments for OSF. The aim of this article is to emphasize on the molecular changes taking place in OSF and possible therapeutic interventions.

Yoithapprabhunath, Thukanaykanpalayam Ragunathan; Maheswaran, Thangadurai; Dineshshankar, Janardhanam; Anusushanth, Abraham; Sindhuja, Pandian; Sitra, Govindasamy

2013-01-01

243

Quality of life in relation to upper and lower respiratory conditions among retired 9\\/11-exposed firefighters with pulmonary disability  

Microsoft Academic Search

Purpose  To examine health-related quality of life (HRQoL) and World Trade Center (WTC) cough syndrome conditions in male firefighters\\u000a who retired due to a 9\\/11-related pulmonary disability.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  From 3\\/1\\/2008 to 1\\/31\\/2009, we contacted 275 disability-retired firefighters and compared their HRQoL and current aerodigestive\\u000a conditions to those from WTC-exposed non-disabled retired and active firefighters. Relationships between HRQoL and explanatory\\u000a variable(s) were examined

Amy Berninger; Mayris P. Webber; Jessica Weakley; Jackson Gustave; Rachel Zeig-Owens; Roy Lee; Fairouz Al-Othman; Hillel W. Cohen; Kerry Kelly; David J. Prezant

2010-01-01

244

[Pathologists and the French network of expertise on rare cancers ENT: The REFCORpath].  

PubMed

Aerodigestive tract tumors are very diverse, either in terms of location, or histologically. Also, this heterogeneity poses particular problems for the histological diagnosis but also for the establishment of the most appropriate treatment. Thus, the network REFCOR (réseau d'expertise français sur les cancers ORL rares/French expert network on rare ENT cancers) was created to better understand these issues, by proposing an epidemiological and diagnostic approach with research collaborations. This network is dedicated to all primary malignant tumors of the salivary glands, ear, nasal cavity and sinuses and all head and neck malignancies other than conventional squamous cell carcinoma. The REFCORpath network consists of expert pathologists and offers, through a network of scanned images, a second opinion or even a third. PMID:24630638

Badoual, Cécile; Baglin, Anne-Catherine; Wassef, Michel; Thariat, Juliette; Reyt, Emile; Janot, François; Baujat, Bertrand

2014-02-01

245

Head and neck cancer screening among 4611 tobacco users older than forty years.  

PubMed

We implemented screening for squamous cell carcinomas of the oral cavity, pharynx, and larynx with symptom assessment and systematic inspection of the oral mucosa by primary care practitioners at health care sites serving inner-city residents of Boston; 4611 tobacco users older than 40 years were screened, and 313 with specific criteria were referred to otolaryngology for diagnostic evaluations. In these screened patients, the prevalence of oral mucosal lesions was almost 13% and prevalence of persistent hoarseness was more than 11%. Although the identification of these cancers was rare (nearly 3%), abnormal findings were seen in more than 70% of referred patients. These clinical and histologic diagnoses are described. We have documented the range of pathologic conditions in high-risk patients screened for upper aerodigestive tract malignancy. PMID:9051065

Prout, M N; Sidari, J N; Witzburg, R A; Grillone, G A; Vaughan, C W

1997-02-01

246

Molecular Pathology of Head and Neck Cancer: Implications for Diagnosis, Prognosis, and Treatment  

PubMed Central

The prototypic head and neck squamous cell carcinoma (HNSCC) arises from the mucosal lining of the upper aerodigestive tract, demonstrates squamous differentiation microscopically, involves older men with a long history of cigarette smoking and alcohol consumption, and is treated by multimodality therapy. HNSCC has long been regarded as a uniform disease process requiring a methodical and unwavering therapeutic approach. Divergence in epidemiologic trends among HNSCCs arising from different anatomic sites has introduced a view that, morphologic repetition aside, head and neck cancers form a heterogeneous group. This view has been supported at the molecular genetic level. A more complete understanding of the molecular genetics of head and neck cancer is providing new insights into long-held but poorly comprehended concepts such as field cancerization and is introducing various biomarkers with potential application for diagnosing, staging, monitoring, and prognosticating HNSCC.

Pai, Sara I.; Westra, William H.

2012-01-01

247

Hypoxia Imaging Endoscopy Equipped with Laser Light Source from Preclinical Live Animal Study to First-In-Human Subject Research  

PubMed Central

A goal in next-generation endoscopy is to develop functional imaging techniques to open up new opportunities for cancer diagnosis. Although spatial and temporal information on hypoxia is crucial for understanding cancer physiology and expected to be useful for cancer diagnosis, existing techniques using fluorescent indicators have limitations due to low spatial resolution and invasive administration. To overcome these problems, we developed an imaging technology based on hemoglobin oxygen saturation in both the tumor and surrounding mucosa using a laser endoscope system, and conducted the first human subject research for patients with aero-digestive tract cancer. The oxygen saturation map overlapped the images of cancerous lesions and indicated highly heterogeneous features of oxygen supply in the tumor. The hypoxic region of the tumor surface was found in both early cancer and cancer precursors. This technology illustrates a novel aspect of cancer biology as a potential biomarker and can be widely utilized in cancer diagnosis.

Kaneko, Kazuhiro; Yamaguchi, Hiroshi; Saito, Takaaki; Yano, Tomonori; Oono, Yasuhiro; Ikematsu, Hiroaki; Nomura, Shogo; Sato, Akihiro; Kojima, Motohiro; Esumi, Hiroyasu; Ochiai, Atsushi

2014-01-01

248

Pediatric radiation oncology  

SciTech Connect

This text covers all aspects of radiation therapy for treatment of pediatric cancer. The book describes the proper use of irradiation in each of the malignancies of childhood, including tumors that are rarely encountered in adult practice. These include acute leukemia; supratentorial brain tumors; tumors of the posterior fossa of the brain and spinal canal; retinoblastoma and optic nerve glioma; neuroblastoma; Hodgkin's disease; malignant lymphoma; Ewing's sarcoma; osteosarcoma; rhabdomyosarcoma; Desmoid tumor; Wilms' tumor; liver and biliary tumors; germ cell and stromal cell tumors of the gonads; endocrine, aerodigestive tract, and breast tumors; Langerhans' cell histiocytosis; and skin cancer and hemangiomas. For each type of malignancy, the authors describe the epidemiology, common presenting signs and symptoms, staging, and proper diagnostic workup. Particular attention is given to the indications for radiation therapy and the planning of a course of radiotherapy, including the optimal radiation dose, field size, and technique.

Halperin, E.C.; Kun, L.E.; Constine, L.S.; Tarbell, N.J.

1989-01-01

249

Oncologic imaging  

SciTech Connect

This text is devoted to the goal of integrating medical imaging into the field of oncology. This book serves as a guide to the appropriate selection and sequencing of the vast array of imaging techniques currently available. Contents: Staging and classification of cancers; Imaging strategies for oncologic diagnosis and staging; Brain and spinal cord neoplasms; The upper aerodigestive tract: cervical lymph node metastases; Thoracic neoplasms; Esophageal cancer; Malignant neoplasms of the pancreas, the liver, and biliary tract; Prostate cancer; Gynecological neoplasms; Hodgkin's disease and the non-Hodgkin's lymphomas; Tumors of the skeletal system; Pediatric oncology; Computed tomography and radiation therapy treatment planning; Contributions of interventional radiology to diagnosis and management of the cancer patient; The impact of future technology on oncologic diagnosis.

Bragg, D.G.; Rubin, P.; Youker, J.E.

1985-01-01

250

Young adults with head and neck cancer express increased susceptibility to mutagen-induced chromosome damage  

SciTech Connect

Factors that contribute to an increased prevalence of squamous cell carcinoma of the upper aerodigestive tract among young adults in the United States remain unknown. A potential etiologic factor may relate to a genetically controlled sensitivity to environmental carcinogens. This study, therefore, examined 20 young adult patients who had squamous cell carcinoma for mutagen-induced chromosome sensitivity. Lymphocytes from respective patients were cultured, exposed to the clastogen bleomycin, arrested during metaphase, and examined quantitatively for chromosome breakage. The young adult population with squamous cell carcinoma expressed a significantly increased number of bleomycin-induced chromosome breaks per cell. Furthermore, among the study patients, chromosome sensitivity was most apparent in the non-tobacco users and in patients less than 30 years of age. The expression of such chromosome fragility following mutagen exposure should be considered in epidemiologic studies that intend to define risk factors for development of head and neck cancer.

Schantz, S.P.; Hsu, T.C.; Ainslie, N.; Moser, R.P. (Univ. of Texas M.D. Anderson Cancer Center, Houston (USA))

1989-12-15

251

Basaloid squamous cell carcinoma in the nasal cavity treated with proton beam therapy concurrent with cisplatin: a case report  

PubMed Central

Introduction Basaloid squamous cell carcinoma is a rare and aggressive variant of squamous cell carcinoma. Basaloid squamous cell carcinoma is mostly seen in the upper aerodigestive tract and has a propensity for lymph node spread and systemic metastases. Various treatment modalities have been reported, including surgical excision supplemented with radiotherapy/adjuvant chemotherapy. To the best of our knowledge, treatment of nasal basaloid squamous cell carcinoma with proton beam therapy and cisplatin has not been described in the literature. Case presentation We report the case of a 56-year-old Japanese man with locally invasive basaloid squamous cell carcinoma in his right nasal cavity with invasion of the orbit, paranasal sinus, and buccal subcutaneous tissue. He underwent proton beam therapy concurrent with cisplatin. Acute and late side effects did not exceed grade 3. At 24-month follow up, he remains in complete remission. Conclusion Proton beam therapy concurrent with cisplatin may be one choice for locally invasive basaloid squamous cell carcinoma.

2014-01-01

252

Acute dysphagia after carp fish meal: a case report.  

PubMed

An 80-year-old man was admitted to the emergency department with acute dysphagia symptoms of 8 hours' duration. The problem began after a carp fish meal. Prominent symptoms included inability to swallow, mild dyspnea, and cough. Laboratory evaluation and fiber-optic examination of the upper aerodigestive tract was normal except for accumulation of saliva in the hypopharynx. Examination with a flexible esophagoscope revealed a total blockage of the lumen of the lower esophagus due to impaction of carp fish roe (column-like formation). With careful maneuvers and water pressure we were able to relieve the obstruction. No other lesion was detectable and no further interventions were needed. Patient follow-up was uneventful. PMID:16369319

Protopappas, Andreas N; Chatziavramidis, Angelos M

2005-01-01

253

Plasma cell mucositis with gingival enlargement and severe periodontitis  

PubMed Central

Plasma cell mucositis (PCM) is a very rare, chronic, multifocal, idiopathic, non-neoplastic plasma cell proliferative disorder of the upper aerodigestive tract. The classic clinical presentation is an intensely erythematous mucosa with surface changes described variously as papillomatous, cobblestone, nodular or velvety. It is a very rare condition <50 cases reported in literature. A 72-year-old male patient complained of sore throat, stomatodynia, dysphagia, multiple oral ulcers, enlarged swollen bleeding gums and mobile teeth. There was chronic inflammatory enlargement of the gingiva and palate with severe periodontitis. Histopathological examination revealed a hyperplastic epithelium with a dense infiltrate of mature polyclonal plasma cells in the superficial layer of the lamina propria. PCM is a diagnosis of exclusion, to be differentiated from other infective, reactive, autoimmune, allergic and neoplastic disorders with plasma cell infiltrates. Management with surgical and immunosuppressive therapy is mostly ineffective with short remissions and frequent relapses.

Gupta, Shalini R.; Gupta, Rajiva; Saran, Ravindra K.; Krishnan, Sriram

2014-01-01

254

Pathogenesis and therapeutic intervention of oral submucous fibrosis.  

PubMed

Oral submucous fibrosis (OSF) is a chronic, progressive, potentially malignant condition affecting the oral cavity and frequently involving the upper part of the aerodigestive tract including the oropharynx and the upper part of the esophagus. It is characterized by juxtaepithelial inflammatory reaction and progressive fibrosis of lamina propria, leading to stiffening of the oral mucosa eventually causing trismus. This condition is associated with significant morbidity and high risk of malignancy. Over the years, several drugs and combinations have been tried for the treatment of submucous fibrosis, but with limited success, because of its unclear molecular pathogenesis. Till date, there are no known effective treatments for OSF. The aim of this article is to emphasize on the molecular changes taking place in OSF and possible therapeutic interventions. PMID:23946584

Yoithapprabhunath, Thukanaykanpalayam Ragunathan; Maheswaran, Thangadurai; Dineshshankar, Janardhanam; Anusushanth, Abraham; Sindhuja, Pandian; Sitra, Govindasamy

2013-06-01

255

[Specific aspects of anesthesiological management of laser surgery in otorhinolaryngology].  

PubMed

Transoral laser surgery has become a standard procedure in the treatment of benign and malignant neoplasms of the upper aerodigestive tract. As the laser cuts and coagulates simultaneously, intraoperative bleeding is reduced, thus improving visualization of the operative field. However, the specific risks for patients and personnel that are associated with this technique necessitate strict compliance with safety regulations and precautions. The safe anesthesiological and surgical management of such procedures requires explicit knowledge of the risks inherent to laser use, as well as close communication between surgeon and anesthesiologist throughout all operative and perioperative procedures. Although potentially fatal complications are rare, surgeon and anesthesiologist need to be aware of the dangers at all times and have exact knowledge of emergency measures. The use of suitable laser-resistant endotracheal tubes, total intravenous anesthesia and an optimized breathing gas mixture can contribute to minimize the occurrence of complications in otorhinolaryngology laser surgery. PMID:25056494

Wetsch, W A; Beutner, D; Stuermer, K J; Padosch, S A

2014-06-01

256

Molecular changes in the multistage pathogenesis of head and neck cancer  

PubMed Central

Head and neck squamous cell carcinomas (SCCHN) arise in the mucosa of the upper aerodigestive tract at multiple anatomic sites. While tobacco and alcohol exposure remain the primary risk factors for this malignancy, infection with the human papilloma virus is emerging as a major contributing factor to cancers that arise primarily in the oropharynx. Despite therapeutic advances, survival has remained relatively unchanged over the past few decades. Increased understand of the cellular and molecular biology of these cancers will improve our understanding of this malignancy and facilitate the development of more effective therapeutic strategies. Alterations that have been studied to date include genetic and epigenetic changes. While the epidermal growth factor receptor (EGFR) is the only established molecular therapeutic target, other proteins and pathways are under active investigation to determine their contribution to SCCHN carcinogenesis and progression.

Park, Brian J.; Chiosea, Simion I.; Grandis, Jennifer R.

2012-01-01

257

Pictorial essay: Salivary gland imaging  

PubMed Central

Salivary glands are the first organs of digestion secreting their digestive juices into the oral cavity. Parotid, submandibular, and sublingual glands are the major paired salivary glands in the decreasing order of their size. In addition, multiple small minor salivary glands are noted randomly distributed in the upper aerodigestive tract, including paranasal sinuses and parapharyngeal spaces. The imaging is directed to the major salivary glands. Commonly used imaging methods include plain radiography and conventional sialography. Recently, high-resolution ultrasonography (HRUS) is being increasingly used for targeted salivary gland imaging. However, the advent of cross-sectional imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) have revolutionized the imaging of salivary glands. This article illustrates the role of imaging in evaluating the variegated disease pattern of the major salivary glands.

Rastogi, Rajul; Bhargava, Sumeet; Mallarajapatna, Govindarajan Janardan; Singh, Sudhir Kumar

2012-01-01

258

[Radiation therapy of sinonasal natural killer/T-cell lymphoma].  

PubMed

Natural killer (NK)/T-cell lymphoma are part of lymphoproliferative diseases, they are rare in Europe and the United States but relatively common in Asia and South America. Natural killer (NK)/T-cell lymphoma present clinically as destructive lesions of the upper aerodigestive tract with perforation of deep structures of the face, destruction of the palate or an invasion of orbits. Treatment modalities of these lymphomas are still discussed because of the lack of available studies and the rarity of this disease. Radiotherapy provides a rapid control of the disease and is positioned as a major treatment of localized stages of NK/T-cell lymphoma of the nasal cavity. We therefore studied the different forms of radiation therapy in the early stages of nasal NK/T-cell lymphoma. PMID:24462054

Riet, F-G; Canova, C-H; Gabarre, J; Ben Hassine, S; Kamsu Kom, L; Mazeron, J-J; Feuvret, L

2014-03-01

259

Marble impaction in the nasopharynx following oral ingestion.  

PubMed

Foreign body ingestion is an important emergency occurring in childhood. In this article, we report the case of a 5-year-old girl with marble impaction in the nasopharynx, which had not been discovered by routine X-rays of the chest and abdomen at the time of ingestion. The patient presented 4 months after the event with typical symptoms of adenoid hypertrophy and sinusitis, and the diagnosis was established on the basis of a plain film of the nasopharynx. This rare situation is potentially dangerous, since the foreign body may descend and cause sudden airway obstruction. Therefore, in all cases with vanishing foreign bodies in the aerodigestive system, nasopharyngeal impaction and its fatal consequences should be kept in mind and endoscopic examination of the region should be considered. PMID:12856130

Oysu, Cagatay; Yilmaz, H Baki; Sahin, A Asli; Külekçi, Mehmet

2003-10-01

260

Hypoxia imaging endoscopy equipped with laser light source from preclinical live animal study to first-in-human subject research.  

PubMed

A goal in next-generation endoscopy is to develop functional imaging techniques to open up new opportunities for cancer diagnosis. Although spatial and temporal information on hypoxia is crucial for understanding cancer physiology and expected to be useful for cancer diagnosis, existing techniques using fluorescent indicators have limitations due to low spatial resolution and invasive administration. To overcome these problems, we developed an imaging technology based on hemoglobin oxygen saturation in both the tumor and surrounding mucosa using a laser endoscope system, and conducted the first human subject research for patients with aero-digestive tract cancer. The oxygen saturation map overlapped the images of cancerous lesions and indicated highly heterogeneous features of oxygen supply in the tumor. The hypoxic region of the tumor surface was found in both early cancer and cancer precursors. This technology illustrates a novel aspect of cancer biology as a potential biomarker and can be widely utilized in cancer diagnosis. PMID:24915532

Kaneko, Kazuhiro; Yamaguchi, Hiroshi; Saito, Takaaki; Yano, Tomonori; Oono, Yasuhiro; Ikematsu, Hiroaki; Nomura, Shogo; Sato, Akihiro; Kojima, Motohiro; Esumi, Hiroyasu; Ochiai, Atsushi

2014-01-01

261

Basaloid squamous cell carcinoma of the tonsil: report of a case and review of the literature  

PubMed Central

The most common type of malignancy affecting the upper aerodigestive tract is squamous cell carcinoma. Basaloid squamous cell carcinoma (BSCC) is a rarely seen, high-grade, bimorphic variant of squamous cell carcinoma, which displays distinct histological features. This entity was first described by Wain et al. in 1986. Since then, approximately 170 cases of head and neck basaloid squamous cell carcinoma have been reported. Tonsils are an uncommon site of occurrence of basaloid cell carcinoma. Only 10 cases of basaloid squamous cell carcinoma arising in the tonsils have been described in current English literature. Histopathologically, these carcinomas are characterised by the presence of a basaloid component in close association with squamous cell carcinoma. In this article, a case of BSCC of the tonsil is reported. The clinical and histopathological features of this tumour are discussed. Relevant literature has been reviewed and differential diagnosis of this tumour is discussed.

Shetty, Deviprasad; Herale, Adarsha; Saldanha, Prema; Jain, Mahaveer

2012-01-01

262

 

PubMed Central

SUMMARY Perivascular epithelioid cell neoplasms are a group of rare tumours reported in various organs under a variety of designations. Such tumours are of interest primarily because of the distinctive morphology of their cell population and their immunoreactivity with melanocytic and myoid markers. There is a strong association between perivascular epithelioid cell neoplasms and tuberous sclerosis complex. Perivascular epithelioid cell neoplasms very rarely occur in the upper aero-digestive tract. To date only three cases of nasal perivascular epithelioid cell neoplasms have been reported in the literature. The present report refers to a 22-year old woman, without any stigmata of tuberous sclerosis complex, with early onset of a polypoid nasal mass with pathological and immunohistochemical features entirely compatible with those of a perivascular epithelioid cell neoplasm.

GANA, S.; MORBINI, P.; GIOURGOS, G.; MATTI, E.; CHU, F.; DANESINO, C.; PAGELLA, F.

2012-01-01

263

Multiple Cancers of the Head and Neck  

PubMed Central

ABSTRACT Multiple head and neck cancers are not rare entities and according to studies in the literature, their incidence is increasing. The emergence of multiple cancers is explained by the phenomenon of "field cancerization". Patients with cancer of the upper digestive and respiratory tract develop most often a second malignancy, usually in the upper aero-digestive tract and among them, those with larynx cancer ranks first among patients with multiple cancers. In the literature and in practice, we met rare combination of multiple cancers, associations that appear to be "random", cannot be explained by any of the hypotheses developed: exposure to carcinogens, genetic susceptibility, and immunodeficiency or cancer treatments after index tumor. Follow-up of patients who have had a head and neck cancer and periodic control are important for early detection of multiple cancers.

HEROIU (CATALOIU), Adriana-Daniela; DANCIU, Cezara Elisabeta; POPESCU, Cristian Radu

2013-01-01

264

Plasma cell mucositis with gingival enlargement and severe periodontitis.  

PubMed

Plasma cell mucositis (PCM) is a very rare, chronic, multifocal, idiopathic, non-neoplastic plasma cell proliferative disorder of the upper aerodigestive tract. The classic clinical presentation is an intensely erythematous mucosa with surface changes described variously as papillomatous, cobblestone, nodular or velvety. It is a very rare condition <50 cases reported in literature. A 72-year-old male patient complained of sore throat, stomatodynia, dysphagia, multiple oral ulcers, enlarged swollen bleeding gums and mobile teeth. There was chronic inflammatory enlargement of the gingiva and palate with severe periodontitis. Histopathological examination revealed a hyperplastic epithelium with a dense infiltrate of mature polyclonal plasma cells in the superficial layer of the lamina propria. PCM is a diagnosis of exclusion, to be differentiated from other infective, reactive, autoimmune, allergic and neoplastic disorders with plasma cell infiltrates. Management with surgical and immunosuppressive therapy is mostly ineffective with short remissions and frequent relapses. PMID:25024555

Gupta, Shalini R; Gupta, Rajiva; Saran, Ravindra K; Krishnan, Sriram

2014-05-01

265

Acetaldehyde as an underestimated risk factor for cancer development: role of genetics in ethanol metabolism.  

PubMed

Chronic ethanol consumption is a strong risk factor for the development of certain types of cancer including those of the upper aerodigestive tract, the liver, the large intestine and the female breast. Multiple mechanisms are involved in alcohol-mediated carcinogenesis. Among those the action of acetaldehyde (AA), the first metabolite of ethanol oxidation is of particular interest. AA is toxic, mutagenic and carcinogenic in animal experiments. AA binds to DNA and forms carcinogenic adducts. Direct evidence of the role of AA in alcohol-associated carcinogenesis derived from genetic linkage studies in alcoholics. Polymorphisms or mutations of genes coding for AA generation or detoxifying enzymes resulting in elevated AA concentrations are associated with increased cancer risk. Approximately 40% of Japanese, Koreans or Chinese carry the AA dehydrogenase 2*2 (ALDH2*2) allele in its heterozygous form. This allele codes for an ALDH2 enzyme with little activity leading to high AA concentrations after the consumption of even small amounts of alcohol. When individuals with this allele consume ethanol chronically, a significant increased risk for upper alimentary tract and colorectal cancer is noted. In Caucasians, alcohol dehydrogenase 1C*1 (ADH1C*1) allele encodes for an ADH isoenzyme which produces 2.5 times more AA than the corresponding allele ADH1C*2. In studies with moderate to high alcohol intake, ADH1C*1 allele frequency and rate of homozygosity was found to be significantly associated with an increased risk for cancer of the upper aerodigestive tract, the liver, the colon and the female breast. These studies underline the important role of acetaldehyde in ethanol-mediated carcinogenesis. PMID:19847467

Seitz, Helmut K; Stickel, Felix

2010-06-01

266

Pharyngeal airway protective reflexes are triggered before the maximum volume of fluid that the hypopharynx can safely hold is exceeded.  

PubMed

Aerodigestive reflexes triggered by pharyngeal stimulation can protect the airways by clearing fluid from the pharynx. The objective of this study was to determine the relationship between the maximum capacity of fluid that can safely dwell in the hypopharynx [hypopharyngeal safe volume (HPSV)] before spilling into the larynx and the threshold volumes required to trigger pharyngoglottal closure reflex (PGCR), pharyngo-upper esophageal sphincter contractile reflex (PUCR), and reflexive pharyngeal swallow (RPS). Twenty-five healthy volunteers (mean age 24 yr, 8 males) were studied in the semi-inclined supine position. PGCR, PUCR, and RPS were elicited using techniques of concurrent upper esophageal sphincter manometry and pharyngo-laryngoscopy. The hypopharynx was then anesthetized to abolish RPS. HPSV was determined by infusing water in the pharynx, and perfusion was stopped when the infusate reached the superior margin of the interarytenoid fold. The threshold volumes for triggering PGCR, PUCR, and RPS by slow and rapid injections before pharyngeal anesthesia were 0.18 ± 0.02 and 0.09 ± 0.02 ml; 0.20 ± 0.020 and 0.13 ± 0.04 ml; and 0.61 ± 0.04 and 0.4 ± 0.06 ml, respectively. All of the above volumes were significantly smaller than the HPSV (0.70 ± 0.06 ml, P < 0.01) except for the threshold volume to elicit RPS during slow perfusion, which was not significantly different (P = 0.23). We conclude that pharyngeal aerodigestive reflexes are triggered by both slow and rapid pharyngeal perfusion of water at significantly smaller volumes than the maximum capacity of the hypopharynx to safely hold contents without spilling into the airway. These reflexes thereby aid in prevention of aspiration. PMID:21566013

Dua, Kulwinder; Surapaneni, Sri Naveen; Kuribayashi, Shiko; Hafeezullah, Muhammad; Shaker, Reza

2011-08-01

267

Pharyngeal airway protective reflexes are triggered before the maximum volume of fluid that the hypopharynx can safely hold is exceeded  

PubMed Central

Aerodigestive reflexes triggered by pharyngeal stimulation can protect the airways by clearing fluid from the pharynx. The objective of this study was to determine the relationship between the maximum capacity of fluid that can safely dwell in the hypopharynx [hypopharyngeal safe volume (HPSV)] before spilling into the larynx and the threshold volumes required to trigger pharyngoglottal closure reflex (PGCR), pharyngo-upper esophageal sphincter contractile reflex (PUCR), and reflexive pharyngeal swallow (RPS). Twenty-five healthy volunteers (mean age 24 yr, 8 males) were studied in the semi-inclined supine position. PGCR, PUCR, and RPS were elicited using techniques of concurrent upper esophageal sphincter manometry and pharyngo-laryngoscopy. The hypopharynx was then anesthetized to abolish RPS. HPSV was determined by infusing water in the pharynx, and perfusion was stopped when the infusate reached the superior margin of the interarytenoid fold. The threshold volumes for triggering PGCR, PUCR, and RPS by slow and rapid injections before pharyngeal anesthesia were 0.18 ± 0.02 and 0.09 ± 0.02 ml; 0.20 ± 0.020 and 0.13 ± 0.04 ml; and 0.61 ± 0.04 and 0.4 ± 0.06 ml, respectively. All of the above volumes were significantly smaller than the HPSV (0.70 ± 0.06 ml, P < 0.01) except for the threshold volume to elicit RPS during slow perfusion, which was not significantly different (P = 0.23). We conclude that pharyngeal aerodigestive reflexes are triggered by both slow and rapid pharyngeal perfusion of water at significantly smaller volumes than the maximum capacity of the hypopharynx to safely hold contents without spilling into the airway. These reflexes thereby aid in prevention of aspiration.

Dua, Kulwinder; Surapaneni, Sri Naveen; Kuribayashi, Shiko; Hafeezullah, Muhammad

2011-01-01

268

Ferret Thoracic Anatomy by 2-Deoxy-2-(18F)Fluoro-D-Glucose (18F-FDG) Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) Imaging  

PubMed Central

The domestic ferret (Mustela putorius furo) has been a long-standing animal model used in the evaluation and treatment of human diseases. Molecular imaging techniques such as 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG) positron emission tomography (PET) would be an invaluable method of tracking disease in vivo, but this technique has not been reported in the literature. Thus, the aim of this study was to establish baseline imaging characteristics of PET/computed tomography (CT) with 18F-FDG in the ferret model. Twelve healthy female ferrets were anesthetized and underwent combined PET/CT scanning. After the images were fused, volumes of interest (VOIs) were generated in the liver, heart, thymus, and bilateral lung fields. For each VOI, standardized uptake values (SUVs) were calculated. Additional comparisons were made between radiotracer uptake periods (60, 90, and >90 minutes), intravenous and intraperitoneal injections of 18F-FDG, and respiratory gated and ungated acquisitions. Pulmonary structures and the surrounding thoracic and upper abdominal anatomy were readily identified on the CT scans of all ferrets and were successfully fused with PET. VOIs were created in various tissues with the following SUV calculations: heart (maximum standardized uptake value [SUVMax] 8.60, mean standardized uptake value [SUVMean] 5.42), thymus (SUVMax 3.86, SUVMean 2.59), liver (SUVMax 1.37, SUVMean 0.99), right lung (SUVMax 0.92, SUVMean 0.56), and left lung (SUVMax 0.88, SUVMean 0.51). Sixty- to 90-minute uptake periods were sufficient to separate tissues based on background SUV activity. No gross differences in image quality were seen between intraperitoneal and intravenous injections of 18F-FDG. Respiratory gating also did not have a significant impact on image quality of lung parenchyma. The authors concluded that 18F-FDG PET and CT imaging can be performed successfully in normal healthy ferrets with the parameters identified in this study. They obtained similar imaging features and uptake measurements with and without respiratory gating as well as with intraperitoneal and intravenous 18F-FDG injections. 18F-FDG PET and CT can be a valuable resource for the in vivo tracking of disease progression in future studies that employ the ferret model.

Wu, Albert; Zheng, Huaiyu; Kraenzle, Jennifer; Biller, Ashley; Vanover, Carol D.; Proctor, Mary; Sherwood, Leslie; Steffen, Marlene; Ng, Chin; Mollura, Daniel J.; Jonsson, Colleen B.

2013-01-01

269

Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.  

SciTech Connect

The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging survivability issues. Our findings indicate that packaging represents the most significant technical challenge associated with application of sensors in the downhole environment for long periods (5+ years) of time. These issues are described in detail within the report. The impact of successful reservoir monitoring programs and coincident improved reservoir management is measured by the production of additional oil and gas volumes from existing reservoirs, revitalization of nearly depleted reservoirs, possible re-establishment of already abandoned reservoirs, and improved economics for all cases. Smart Well monitoring provides the means to understand how a reservoir process is developing and to provide active reservoir management. At the same time it also provides data for developing high-fidelity simulation models. This work has been a joint effort with Sandia National Laboratories and UT-Austin's Bureau of Economic Geology, Department of Petroleum and Geosystems Engineering, and the Institute of Computational and Engineering Mathematics.

Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim (University of Texas at Austin, Austin, TX); Gilbert, Bob (University of Texas at Austin, Austin, TX); Lake, Larry W. (University of Texas at Austin, Austin, TX); Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX); Thomas, Sunil G. (University of Texas at Austin, Austin, TX); Rightley, Michael J.; Rodriguez, Adolfo (University of Texas at Austin, Austin, TX); Klie, Hector (University of Texas at Austin, Austin, TX); Banchs, Rafael (University of Texas at Austin, Austin, TX); Nunez, Emilio J. (University of Texas at Austin, Austin, TX); Jablonowski, Chris (University of Texas at Austin, Austin, TX)

2006-11-01

270

Errors in MR-based attenuation correction for brain imaging with PET/MR scanners  

NASA Astrophysics Data System (ADS)

AimAttenuation correction of PET data acquired by hybrid MR/PET scanners remains a challenge, even if several methods for brain and whole-body measurements have been developed recently. A template-based attenuation correction for brain imaging proposed by our group is easy to handle and delivers reliable attenuation maps in a short time. However, some potential error sources are analyzed in this study. We investigated the choice of template reference head among all the available data (error A), and possible skull anomalies of the specific patient, such as discontinuities due to surgery (error B). Materials and methodsAn anatomical MR measurement and a 2-bed-position transmission scan covering the whole head and neck region were performed in eight normal subjects (4 females, 4 males). Error A: Taking alternatively one of the eight heads as reference, eight different templates were created by nonlinearly registering the images to the reference and calculating the average. Eight patients (4 females, 4 males; 4 with brain lesions, 4 w/o brain lesions) were measured in the Siemens BrainPET/MR scanner. The eight templates were used to generate the patients' attenuation maps required for reconstruction. ROI and VOI atlas-based comparisons were performed employing all the reconstructed images. Error B: CT-based attenuation maps of two volunteers were manipulated by manually inserting several skull lesions and filling a nasal cavity. The corresponding attenuation coefficients were substituted with the water's coefficient (0.096/cm). ResultsError A: The mean SUVs over the eight templates pairs for all eight patients and all VOIs did not differ significantly one from each other. Standard deviations up to 1.24% were found. Error B: After reconstruction of the volunteers' BrainPET data with the CT-based attenuation maps without and with skull anomalies, a VOI-atlas analysis was performed revealing very little influence of the skull lesions (less than 3%), while the filled nasal cavity yielded an overestimation in cerebellum up to 5%. ConclusionsThe present error analysis confirms that our template-based attenuation method provides reliable attenuation corrections of PET brain imaging measured in PET/MR scanners.

Rota Kops, Elena; Herzog, Hans

2013-02-01

271

EQPlanar: a maximum-likelihood method for accurate organ activity estimation from whole body planar projections  

NASA Astrophysics Data System (ADS)

Optimizing targeted radionuclide therapy requires patient-specific estimation of organ doses. The organ doses are estimated from quantitative nuclear medicine imaging studies, many of which involve planar whole body scans. We have previously developed the quantitative planar (QPlanar) processing method and demonstrated its ability to provide more accurate activity estimates than conventional geometric-mean-based planar (CPlanar) processing methods using physical phantom and simulation studies. The QPlanar method uses the maximum likelihood-expectation maximization algorithm, 3D organ volume of interests (VOIs), and rigorous models of physical image degrading factors to estimate organ activities. However, the QPlanar method requires alignment between the 3D organ VOIs and the 2D planar projections and assumes uniform activity distribution in each VOI. This makes application to patients challenging. As a result, in this paper we propose an extended QPlanar (EQPlanar) method that provides independent-organ rigid registration and includes multiple background regions. We have validated this method using both Monte Carlo simulation and patient data. In the simulation study, we evaluated the precision and accuracy of the method in comparison to the original QPlanar method. For the patient studies, we compared organ activity estimates at 24 h after injection with those from conventional geometric mean-based planar quantification using a 24 h post-injection quantitative SPECT reconstruction as the gold standard. We also compared the goodness of fit of the measured and estimated projections obtained from the EQPlanar method to those from the original method at four other time points where gold standard data were not available. In the simulation study, more accurate activity estimates were provided by the EQPlanar method for all the organs at all the time points compared with the QPlanar method. Based on the patient data, we concluded that the EQPlanar method provided a substantial increase in accuracy of organ activity estimates from 24 h planar images compared to the CPlanar using 24 h SPECT as the golden standard. For other time points, where no golden standard is available, better agreement between estimated and measured projections was observed by using the EQPlanar method compared to the QPlanar method. This phenomenon is consistent with the improvement in goodness of fit seen in both simulation data and 24 h patient data. Therefore, this indicates the improved reliability of organ activity estimates obtained though the EQPlanar method.

Song, N.; He, B.; Wahl, R. L.; Frey, E. C.

2011-09-01

272

Construction and Evaluation of Quantitative Small-Animal PET Probabilistic Atlases for [18F]FDG and [18F]FECT Functional Mapping of the Mouse Brain  

PubMed Central

Automated voxel-based or pre-defined volume-of-interest (VOI) analysis of small-animal PET data in mice is necessary for optimal information usage as the number of available resolution elements is limited. We have mapped metabolic ([18F]FDG) and dopamine transporter ([18F]FECT) small-animal PET data onto a 3D Magnetic Resonance Microscopy (MRM) mouse brain template and aligned them in space to the Paxinos co-ordinate system. In this way, ligand-specific templates for sensitive analysis and accurate anatomical localization were created. Next, using a pre-defined VOI approach, test-retest and intersubject variability of various quantification methods were evaluated. Also, the feasibility of mouse brain statistical parametric mapping (SPM) was explored for [18F]FDG and [18F]FECT imaging of 6-hydroxydopamine-lesioned (6-OHDA) mice. Methods Twenty-three adult C57BL6 mice were scanned with [18F]FDG and [18F]FECT. Registrations and affine spatial normalizations were performed using SPM8. [18F]FDG data were quantified using (1) an image-derived-input function obtained from the liver (cMRglc), using (2) standardized uptake values (SUVglc) corrected for blood glucose levels and by (3) normalizing counts to the whole-brain uptake. Parametric [18F]FECT binding images were constructed by reference to the cerebellum. Registration accuracy was determined using random simulated misalignments and vectorial mismatch determination. Results Registration accuracy was between 0.21–1.11 mm. Regional intersubject variabilities of cMRglc ranged from 15.4% to 19.2%, while test-retest values were between 5.0% and 13.0%. For [18F]FECT uptake in the caudate-putamen, these values were 13.0% and 10.3%, respectively. Regional values of cMRglc positively correlated to SUVglc measured within the 45–60 min time frame (spearman r?=?0.71). Next, SPM analysis of 6-OHDA-lesioned mice showed hypometabolism in the bilateral caudate-putamen and cerebellum, and an unilateral striatal decrease in DAT availability. Conclusion MRM-based small-animal PET templates facilitate accurate assessment and spatial localization of mouse brain function using VOI or voxel-based analysis. Regional intersubject- and test-retest variations indicate that for these targets accuracy comparable to humans can be achieved.

Casteels, Cindy; Vunckx, Kathleen; Aelvoet, Sarah-Ann; Baekelandt, Veerle; Bormans, Guy; Van Laere, Koen; Koole, Michel

2013-01-01

273

Could 18 F-DPA-714 PET imaging be interesting to use in the early post-stroke period?  

PubMed Central

Background Cerebral stroke is a severe and frequent condition that requires rapid and reliable diagnosis. If administered shortly after the first symptoms manifest themselves, IV thrombolysis has been shown to increase the functional prognosis by restoring brain reperfusion. However, a better understanding of the pathophysiology of stroke should help to identify potential new therapeutic targets. Stroke is known to induce an inflammatory brain reaction that involves overexpression of the 18-kDa translocator protein (TSPO) in glial cells and infiltrated leukocytes, which can be visualised by positron emission tomography (PET). We aimed to evaluate post-stroke neuroinflammation using the PET TSPO radioligand 18?F-DPA-714. Methods Nine patients underwent 18?F-DPA-714 PET and magnetic resonance imaging (MRI) between 8 and 18 days after the ictus. Co-registration of MRI and PET images was used to define three volumes of interest (VOIs): core infarction, contralateral region, and cerebellum ipsilateral to the stroke lesion. Time activity curves were obtained from each VOI, and ratios of mean and maximum activities between the VOIs were calculated. Results We observed an increased uptake of 18?F-DPA-714 co-localised with the infarct tissue and extension beyond the region corresponding to the damage in the blood brain barrier. No correlation was identified between 18?F-DPA-714 uptake and infarct volume. 18?F-DPA-714 uptake in ischemic lesion (mainly associated with TSPO expression in the infarct area and in the surrounding neighbourhood) slowly decreased from 10 min pi to the end of the PET acquisition, remaining higher than that in both contralateral region and ipsilateral cerebellum. Conclusion Our results show that 18?F-DPA-714 uptake after acute ischemia is mainly associated with TSPO expression in the infarct area and in the surrounding neighbourhood. We also demonstrated that the kinetics of 18?F-DPA-714 differs in injured tissue compared to normal tissue. Therefore, 18?F-DPA-714 may be useful in assessing the extent of neuroinflammation associated with acute stroke and could also help to predict clinical outcomes and functional recovery, as well as to assess therapeutic strategies, such as the use of neuroprotective/anti-inflammatory drugs.

2014-01-01

274

Transfer of normal 99mTc-ECD brain SPET databases between different gamma cameras.  

PubMed

A stereotactic, normal perfusion database is imperative for optimal clinical brain single-photon emission tomography (SPET). However, interdepartmental use of normal data necessitates accurate transferability of these data sets. The aim of this study was to investigate transfer of three normal perfusion databases obtained in the same large population of healthy volunteers who underwent sequential scanning using multihead gamma cameras with different resolution. Eighty-nine healthy adults (46 females, 43 males; aged 20-81 years) were thoroughly screened by history, biochemistry, physical and full neurological examination, neuropsychological testing and magnetic resonance imaging. After injection of 925 MBq technetium-99m labelled ethyl cysteinate dimer (ECD) under standard conditions, 101 scans were acquired from all subjects (12 repeat studies) on a triple-head Toshiba GCA-9300A (measured average FWHM 8.1 mm). Ninety-one sequential scans were performed on a dual-head Elscint Helix camera (FWHM 9.6 mm) and 22 subjects also underwent imaging on a triple-head Prism 3000 (FWHM 9.6 mm). Images were transferred to the same processing platform and reconstructed by filtered back-projection with the same Butterworth filter (order 8, cut-off 0.9 cycles/cm) and uniform Sorensen attenuation correction (mu = 0.09). After automated rigid intrasubject registration, all subjects were automatically reoriented to a stereotactic template by a nine-parameter affine transformation. The databases were analysed using 35 predefined volumes of interest (VOIs) with normalisation on total VOI counts. For comparison, the high-resolution data were smoothed with a 3D Gaussian kernel to achieve more similar spatial resolution. Hoffman phantom measurements were conducted on all cameras. Partial volume effects after smoothing varied between -6.5% and 10%, depending on VOI size. Between-camera reproducibility was 2.5% and 2.7% for the Toshiba camera versus the Helix and the Prism database, respectively. The highest reduction in between-camera variability was achieved by resolution adjustment in combination with linear washout correction and a Hoffman phantom-based correction. In conclusion, transfer of normal perfusion data between multihead gamma cameras can be accurately achieved, thereby enabling widespread interdepartmental use, which is likely to have a positive impact on the diagnostic capabilities of clinical brain perfusion SPET. PMID:11357493

Van Laere, K; Koole, M; Versijpt, J; Vandenberghe, S; Brans, B; D'Asseler, Y; De Winter, O; Kalmar, A; Dierckx, R

2001-04-01

275

An economic value of remote-sensing information—Application to agricultural production and maintaining groundwater quality  

USGS Publications Warehouse

Does remote-sensing information provide economic benefits to society, and can a value be assigned to those benefits? Can resource management and policy decisions be better informed by coupling past and present Earth observations with groundwater nitrate measurements? Using an integrated assessment approach, the U.S. Geological Survey (USGS) applied an established conceptual framework to answer these questions, as well as to estimate the value of information (VOI) for remote-sensing imagery. The approach uses moderate-resolution land-imagery (MRLI) data from the Landsat and Advanced Wide Field Sensor satellites that has been classified by the National Agricultural Statistics Service into the Cropland Data Layer (CDL). Within the constraint of the U.S. Environmental Protection Agency's public health threshold for potable groundwater resources, the USGS modeled the relation between a population of the CDL's land uses and dynamic nitrate (NO3-) contamination of aquifers in a case study region in northeastern Iowa. Employing various multiscaled, multitemporal geospatial datasets with MRLI to maximize the value of agricultural production, the approach develops and uses multiple environmental science models to address dynamic nitrogen loading and transport at specified distances from specific sites (wells) and at landscape scales (for example, across 35 counties and two aquifers). In addition to the ecosystem service of potable groundwater, this effort focuses on the use of MRLI for the management of the major land uses in the study region-the production of corn and soybeans, which can impact groundwater quality. Derived methods and results include (1) economic and dynamic nitrate-pollution models, (2) probabilities of the survival of groundwater, and (3) a VOI for remote sensing. For the northeastern Iowa study region, the marginal benefit of the MRLI VOI (in 2010 dollars) is $858 million ±$197 million annualized, which corresponds to a net present value of $38.1 billion ±$8.8 billion for that flow of benefits in perpetuity. Given that these economic estimates are derived from one case study in a part of only one State, the estimates provide a lower estimate related to the potential value of the Landsat Data Continuity Mission.

Forney, William M.; Raunikar, Ronald P.; Bernknopf, Richard L.; Mishra, Shruti K.

2012-01-01

276

Averaging of diffusion tensor imaging direction-encoded color maps for localizing substantia nigra.  

PubMed

Diffusion tensor imaging (DTI) is a form of MRI that has been used extensively to map in vivo the white matter architecture of the human brain. It is also used for mapping subcortical nuclei because of its general sensitivity to tissue orientation differences and effects of iron accumulation on the diffusion signal. While DTI provides excellent spatial resolution in individual subjects, a challenge is visualizing consistent patterns of diffusion orientation across subjects. Here we present a simple method for averaging direction-encoded color anisotropy maps in standard space, explore this technique for visualizing the substantia nigra (SN) in relation to other midbrain structures, and show with signal-to-noise analysis that averaging improves the direction-encoded color signature. SN is distinguished on averaged maps from neighboring structures, including red nucleus (RN) and cerebral crus, and is proximal to SN location from existing brain atlases and volume of interest (VOI) delineation on individual scans using two blinded raters. PMID:24905890

Ellmore, Timothy M; Murphy, Sara M; Cruz, Katarina; Castriotta, Richard J; Schiess, Mya C

2014-08-01

277

Les Troubles Respiratoires Chez Le Brule  

PubMed Central

Summary A travers une revue de la littérature, cet article se propose d'exposer les particularités des troubles respiratoires chez le brûlé. Ces troubles sont liés à un mécanisme direct, lorsque l'arbre respiratoire est lésé par le transfert d'énergie thermique du à la brûlure et/ou par un mécanisme indirect, lorsque la fonction respiratoire et ventilatoire du poumon est perturbée par les phénomènes loco-régionaux ou généraux du brûlé. Ces troubles respiratoires sont aggravés par l'inhalation des gaz contenus dans la fumée d'incendie. Le diagnostic de ces troubles est clinique et paraclinique. Il doit être précoce et continu. Les patients nécessitent de différents moyens thérapeutiques tels que l'oxygénothérapie, la libération des voies respiratoires, l'amélioration de la mécanique ventilatoire et de la fonction respiratoire, l'antibiothérapie ou la chirurgie des séquelles. Cette prise en charge doit nécessairement être multidisciplinaire.

Fassi Fihri, J.; Ezzoubi, M.; Boukind, E.H.

2010-01-01

278

Le contr?le des infections au cabinet du p?diatre  

PubMed Central

RÉSUMÉ La transmission des infections au cabinet du pédiatre est de plus en plus préoccupante. Le présent document expose les voies de transmission des infections et les principes sous-jacents aux mesures actuelles pour contrôler les infections. Pour prévenir les infections, il faut bien concevoir le cabinet et adopter des politiques administratives et de triage convenables, de même que des pratiques de base pour les soins de tous les patients (p. ex., hygiène des mains, port de gants, de masques, de lunettes de protection et d’une blouse d’hôpital pour des interventions précises; nettoyage, désinfection et stérilisation convenables des surfaces et du matériel, y compris les jouets, et techniques d’asepsie en cas d’interventions effractives) et des précautions additionnelles en cas d’infections précises. Le personnel doit avoir reçu les vaccins pertinents, et les personnes infectées doivent respecter les politiques de restriction au travail.

2008-01-01

279

In vivo FID-based 3D Multivoxel Longitudinal Hadamard Spectroscopic Imaging In the Human Brain at 3 T  

PubMed Central

We propose and demonstrate a full 3D longitudinal Hadamard Spectroscopic Imaging (L-HSI) scheme for obtaining chemical shift maps, by employing adiabatic inversion pulses to encode the spins’ positions. The approach offers several advantages over conventional Fourier-based encoding methods, including a localized point spread function; no aliasing, allowing for VOIs smaller than the object being imaged; an option for acquiring non-contiguous voxels; and inherent outer volume rejection. The latter allows for doing away with conventional outer volume suppression schemes, such as PRESS or STEAM, and acquiring non spin-echo spectra with short acquisition delay times, limited only by the excitation pulse’s duration. This, in turn, minimizes T2 decay, maximizes the signal to noise ratio, and reduces J-coupling induced signal decay. Results are presented for both a phantom and an in-vivo healthy volunteer at 3T.

Tal, Assaf; Goelman, Gadi; Gonen, Oded

2012-01-01

280

La pr?vention de l'infection par le virus respiratoire syncytial  

PubMed Central

L’infection par le virus respiratoire syncytial (VRS) est la principale cause d’infection des voies respiratoires inférieures chez les jeunes enfants et pour cette raison, bon nombre des prématurés et des enfants présentant d’autres facteurs de risque doivent être hospitalisés chaque année au Canada. Le palivizumab, un anticorps monoclonal anti-VRS, peut réduire le taux d’hospitalisation et la gravité de la maladie d’un petit groupe de prématurés ou de nourrissons à haut risque pendant leur première saison de VRS. Le présent document de principes contient une analyse des publications ainsi que des recommandations à l’intention des médecins canadiens au sujet de son utilisation chez les prématurés et les autres nourrissons à risque.

Samson, L

2009-01-01

281

High-resolution micro-SPECT to evaluate the regional brain perfusion in the adult Beagle dog.  

PubMed

Conventional Single Photon Emission Computed Tomography (SPECT) precludes a detailed evaluation of the subcortical region. Micro-SPECT (?-SPECT) has a higher resolution, but has not been used to evaluate the dog's brain until now. In this study, ?-SPECT of the brain was evaluated in 10 Beagle dogs. Magnetic Resonance Imaging (MRI) of the brain was used to draw a new region map containing 19 volumes of interest (VOIs). Semi-quantitative analysis of the ?-SPECT data was performed and the regional cerebral perfusion was represented by the perfusion indices (PIs). The highest perfusion was found in the parietal cortex and the lowest in the piriform cortex. An asymmetry toward the left hemisphere in general and a regional asymmetry in the frontal, temporal and parietal cortex were found. This study shows that functional imaging of the canine brain is possible using ?-SPECT and it describes the normal regional brain perfusion in the adult Beagle dog. PMID:23261153

Martlé, V; Peremans, K; Van Ham, L; Vermeire, S; Waelbers, T; Dobbeleir, A; Gielen, I; Boon, P; Claes, K; Bhatti, S

2013-06-01

282

A 13C-NMR study of exopolysaccharide synthesis in Rhizobium meliloti Su47 strain  

NASA Astrophysics Data System (ADS)

Metabolic pathways implied in the synthesis of succinoglycan produced by the Su47 strain of R. meliloti were evaluated by 13C-NMR spectroscopy after incubation with [1{-}13C] or [2{-}13C] glucose. The biosynthesis of this polymer by R. meliloti from glucose occurred by a direct polymerisation of the introduced glucose and by the pentose phosphate pathway. Les voies métaboliques impliquées dans la synthèse du succinoglycane produit par la souche Su47 de R. meliloti ont été évaluées par la spectroscopie de RMN du carbone 13 après incubation des cellules avec du [1{-}13C] ou [2{-}13C] glucose. La biosynthèse de ce polymère à partir du glucose se produit par polymérisation directe du glucose et par la voie des pentoses phosphate.

Tavernier, P.; Portais, J.-C.; Besson, I.; Courtois, J.; Courtois, B.; Barbotin, J.-N.

1998-02-01

283

A near-infrared stellar spectral library: I. H-band spectra.  

NASA Astrophysics Data System (ADS)

This paper presents the H band near-infrared (NIR) spectral library of 135 solar type stars covering spectral types O5-M3 and luminosity classes I-V as per MK classification. The observations were carried out with 1.2 meter Gurushikhar Infrared Telescope (GIRT), at Mt. Abu, India using a NICMOS3 HgCdTe 256 x 256 NIR array based spectrometer. The spectra have a moderate resolution of 1000 (about 16 A) at the H band and have been continuum shape corrected to their respective effective temperatures. This library and the remaining ones in J and K bands once released will serve as an important database for stellar population synthesis and other applications in conjunction with the newly formed large optical coude feed stellar spectral library of Valdes et al. (2004). The complete H-Band library is available online at: http://vo.iucaa.ernet.in/~voi/NIR_Header.html

Ranade, Arvind; Gupta, Ranjan; Ashok, N. M.; Singh, Harinder P.

2004-12-01

284

Simulation modeling to derive the value-of-information for risky animal disease-import decisions.  

PubMed

Simulation modeling can be used in aiding decision-makers in deciding when to invest in additional research and when the risky animal disease-import decision should go forward. Simulation modeling to evaluate value-of-information (VOI) techniques provides a robust, objective and transparent framework for assisting decision-makers in making risky animal and animal product decisions. In this analysis, the hypothetical risk from poultry disease in chicken-meat imports was modeled. Economic criteria were used to quantify alternative confidence-increasing decisions regarding potential import testing and additional research requirements. In our hypothetical example, additional information about poultry disease in the exporting country (either by requiring additional export-flock surveillance that results in no sign of disease, or by conducting additional research into lack of disease transmittal through chicken-meat ingestion) captured >75% of the value-of-information attainable regarding the chicken-meat-import decision. PMID:14554141

Disney, W Terry; Peters, Mark A

2003-11-12

285

MOND : la nouvelle théorie de l'Univers  

NASA Astrophysics Data System (ADS)

La théorie du Big Bang est face à un dilemme. Ses équations semblent parfaites mais les "ingrédients" auxquels celles-ci font appel demeurent pour l'instant totalement hypothétiques... Ils ont pour nom "matière noire" et "énergie noire" et ne représenteraient pas moins de 95% de l'Univers. Dans cette situation de "crise", une théorie élaborée en 1983, revient sur le devant de la scène. Il s'agit de MOND, une modification de la gravitation imaginée par l'israëlien Mordeghai Milgrom, qui élimine au moins une partie de ces ingrédients de nature inconnue. Même si elle doit être encore validée par des observations, sa résurrection symbolise le besoin, pour les cosmologistes, de trouver de nouvelles voies pour décrire l'Univers.

Bonnet-Bidaud, J. M.

2006-12-01

286

Probabilistic graphical models and their application in data fusion  

NASA Astrophysics Data System (ADS)

Probabilistic graphical models, in particular Bayesian networks, provide a consistent framework in which to address problems containing uncertainty and complexity. Probabilistic inference in high-dimensional problems only becomes tractable when the system can be made modular by imposing meaningful conditional independence assumptions. Bayesian networks provide a natural way to accomplish this. As a combination of probability theory and graph theory, the probabilistic aspects of a graphical model provide a consistent way of connecting data to models, while graph theory provides an intuitively appealing interface to express independence assumptions as well as efficient computation algorithms. A detailed example demonstrating various aspects of Bayesian networks for an electronic intelligence (ELINT) sensor data fusion decision system is presented, including a Value of Information (VOI) analysis.

Bottone, Steven; Stanek, Clay

2007-04-01

287

The Prognostic Value of 18F-FDG PET/CT for Hepatocellular Carcinoma Treated with Transarterial Chemoembolization (TACE)  

PubMed Central

18F-Fluoro-deoxyglucose (FDG) PET/CT can be used to monitor the biological behavior of hepatocellular carcinoma (HCC). Baseline PET/CT has prognostic value in HCC patients, but there is litter knowledge of the PET/CT changes after treatment. We evaluated 27 HCC patients treated with transarterial chemoembolization (TACE) from June 2011 to July 2012, and we investigated the prognostic value of PET/CT. Patients were followed up with regular clinical and laboratory examinations and contrast-enhanced spiral computed tomography (CT). Furthermore, PET/CT assessments were collected and analyzed before (range 1~15 d) and after the first month of TACE (range, 27~45d). We tested the prognostic value of the tumor standardized uptake value (TSUV) and normal liver SUV(LSUV) according to the VOI (volume of interest). The SUVs were used to assess the relationship between the treatment response and survival. To assess their prognostic value, we evaluated the areas under the receiver operating characteristic (ROC) curves of different SUVs for predicting survival. Finally, the median overall survival (OS) and time to progression (TTP) for 27 patients were 15.4 months (95%CI, 3.3-27.5 months) and 11.4 months (95%CI, 6.7-16.1 months), respectively. The ?TSUVmax%, based on the VOI, had the highest discriminative prognostic value and the cutoff PET/CT response was 0.1 with a sensitivity of 100% and a specificity of 95.2%. The OS was significantly better in the PET/CT response group than in the PET/CT non-response group (p=0.025). In conclusion, an early interim PET/CT after TACE may have prognostic value for HCC patients treated with TACE, and the ?TSUVmax% may help in determining the HCCs viability in patients with high baseline and follow-up18F-FDG uptake.

Ma, Wenhui; Jia, Jia; Wang, Shengjun; Bai, Wei; Yi, Jingwei; Bai, Ming; Quan, Zhiyong; Yin, Zhanxin; Fan, Daiming; Wang, Jing; Han, Guohong

2014-01-01

288

Fiducial-less 2D-3D spine image registration using spine region segmented in CT image  

NASA Astrophysics Data System (ADS)

The target pose (position and orientation) of a spinal lesion can be determined using image registration of a pair of two-dimensional (2D) x-ray projection images and a pre-treatment three-dimensional (3D) CT image. This is useful for detecting, tracking and correcting for patient movement during image-guided spinal radiotherapy and radiosurgery. We recently developed a fiducial-less 2D-3D spine image registration that localizes spinal targets by directly tracking adjacent skeletal structures and thereby eliminates the need for implanted fiducials. Experience has shown this method to be robust under a wide range of clinical circumstances. However, image artifacts in digitally reconstructed radiographs (DRRs) that can be introduced by breathing during CT scanning or by other surrounding structures such as ribs have the negative effects on image registration performance. Therefore, we present an approach to eliminate the image artifacts in DRRs for a more robust registration. The spinal structures in the CT volume are approximately segmented in a semi-automatic way and saved as a volume of interest (VOI). The DRRs are then generated within the spine VOI for two orthogonal projections. During radiation treatment delivery, two X-ray images are acquired simultaneously in near real time. Then each X-ray image is registered with the DRR image to obtain 2D local displacements of skeletal structures. The 3D tumor position is calculated from the 2D displacements by 2D-to-3D back-projection and geometric transformation. Experiments on clinical data were conducted to evaluate the performance of the improved registration. The results showed that spine segmentation substantially improves image registration performance.

Fu, Dongshan; Wang, Hongwu; Maurer, Calvin R., Jr.; Kuduvalli, Gopinath

2007-03-01

289

Progressive White Matter Microstructure Damage in Male Chronic Heroin Dependent Individuals: A DTI and TBSS Study  

PubMed Central

Background To investigate the WM microstructure deficits in heroin dependent individuals (HDIs) with different length of heroin dependence, and to investigate whether these WM deficits can be related to the duration of heroin use and to decision-making deficits in HDIs. Methodology/Principal Findings Thirty-six HDIs [including eighteen sHDIs (duration of heroin dependent is less than 10 years) and eighteen lHDIs (duration of dependent is between 10?20 years)] and sixteen healthy controls participated in this study. Whole brain voxel-wise analysis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (Da) and radial diffusivity (Dr) were performed by tract-based spatial statistics (TBSS) to localize abnormal WM regions among groups. TBSS demonstrated that sHDIs had significantly lower FA than controls in right orbito-frontal WM, bilateral temporal WM and right parietal WM. The lHDIs had significantly lower FA throughout the brain compared with the controls and sHDIs. The lHDIs had significantly lower Da than controls in bilateral inferior frontaloccipital fasciculus, bilateral splenium of corpus callosum, left inferior longitudinal fasciculus, and had significantly higher Dr than controls in bilateral uncinatus fasciculus, bilateral inferior frontaloccipital fasciculus and bilateral cortical spinal fasciculus. Volume-of-interest (VOI) analyses detect the changes of diffusivity indices in the regions with FA abnormalities revealed by control vs sHDIs. In most VOIs, FA reductions were caused by the increase in Dr as well as the decrease in Da. Correlation analysis was used to assess the relationship between FA and behavioral measures in HDIs and controls available. Significantly positively correlations were found between the FA values in the right orbital-frontal WM, right parietal WM and IGT performance. Conclusions The extent and severity of WM integrity deficits in HDIs was associated with the length of heroin dependent. Furthermore, abnormal WM microstructure may correlate with decision-making impairments in HDIs.

Su, Huanhuan; Lv, Xiaofei; Zhang, Xuelin; Tian, Junzhang; Zhuo, Fuzhen

2013-01-01

290

A minimally interactive method to segment enlarged lymph nodes in 3D thoracic CT images using a rotatable spiral-scanning technique  

NASA Astrophysics Data System (ADS)

Precise size measurement of enlarged lymph nodes is a significant indicator for diagnosing malignancy, follow-up and therapy monitoring of cancer diseases. The presence of diverse sizes and shapes, inhomogeneous enhancement and the adjacency to neighboring structures with similar intensities, make the segmentation task challenging. We present a semi-automatic approach requiring minimal user interactions to fast and robustly segment the enlarged lymph nodes. First, a stroke approximating the largest diameter of a specific lymph node is drawn manually from which a volume of interest (VOI) is determined. Second, Based on the statistical analysis of the intensities on the dilated stroke area, a region growing procedure is utilized within the VOI to create an initial segmentation of the target lymph node. Third, a rotatable spiral-scanning technique is proposed to resample the 3D boundary surface of the lymph node to a 2D boundary contour in a transformed polar image. The boundary contour is found by seeking the optimal path in 2D polar image with dynamic programming algorithm and eventually transformed back to 3D. Ultimately, the boundary surface of the lymph node is determined using an interpolation scheme followed by post-processing steps. To test the robustness and efficiency of our method, a quantitative evaluation was conducted with a dataset of 315 lymph nodes acquired from 79 patients with lymphoma and melanoma. Compared to the reference segmentations, an average Dice coefficient of 0.88 with a standard deviation of 0.08, and an average absolute surface distance of 0.54mm with a standard deviation of 0.48mm, were achieved.

Wang, Lei; Moltz, Jan H.; Bornemann, Lars; Hahn, Horst K.

2012-02-01

291

Breast mass segmentation on dynamic contrast-enhanced magnetic resonance scans using the level set method  

NASA Astrophysics Data System (ADS)

The goal of this study was to develop an automated method to segment breast masses on dynamic contrast-enhanced (DCE) magnetic resonance (MR) scans that were performed to monitor breast cancer response to neoadjuvant chemotherapy. A radiologist experienced in interpreting breast MR scans defined the mass using a cuboid volume of interest (VOI). Our method then used the K-means clustering algorithm followed by morphological operations for initial mass segmentation on the VOI. The initial segmentation was then refined by a three-dimensional level set (LS) method. The velocity field of the LS method was formulated in terms of the mean curvature which guaranteed the smoothness of the surface and the Sobel edge information which attracted the zero LS to the desired mass margin. We also designed a method to reduce segmentation leak by adapting a region growing technique. Our method was evaluated on twenty DCE-MR scans of ten patients who underwent neoadjuvant chemotherapy. Each patient had pre- and post-chemotherapy DCE-MR scans on a 1.5 Tesla magnet. Computer segmentation was applied to coronal T1-weighted images. The in-plane pixel size ranged from 0.546 to 0.703 mm and the slice thickness ranged from 2.5 to 4.0 mm. The flip angle was 15 degrees, repetition time ranged from 5.98 to 6.7 ms, and echo time ranged from 1.2 to 1.3 ms. The computer segmentation results were compared to the radiologist's manual segmentation in terms of the overlap measure defined as the ratio of the intersection of the computer and the radiologist's segmentations to the radiologist's segmentation. Pre- and post-chemotherapy masses had overlap measures of 0.81+/-0.11 (mean+/-s.d.) and 0.70+/-0.21, respectively.

Shi, Jiazheng; Sahiner, Berkman; Chan, Heang-Ping; Paramagul, Chintana; Hadjiiski, Lubomir M.; Helvie, Mark; Wu, Yi-Ta; Ge, Jun; Zhang, Yiheng; Zhou, Chuan; Wei, Jun

2008-04-01

292

Corticostriatal covariance patterns of 6-[18F]fluoro-L-dopa and [18F]fluorodeoxyglucose PET in Parkinson's disease.  

PubMed

6-[18F]fluoro-L-dopa (FDOPA) is a common presynaptic dopaminergic tracer used in examinations by positron emission tomography (PET) for patients with Parkinson's disease (PD). The distinct metabolic covariance pattern in the uptake of [18F]fluorodeoxyglucose (FDG) can also be used to investigate PD pathology. Although the two tracers are widely used in PD research and clinical assessment, no thorough comparative studies of the tracers have been made. In this study, 25 PD patients were examined with FDOPA and FDG to investigate relationships and clinical correlates of metabolic and monoaminergic function in the Parkinsonian brain. A VOI (volume-of-interest) analysis was achieved by 3D spatial normalisation and fixed VOI-sets. The hemisphere ipsi- and contralateral to the predominant symptoms of PD was identified in each data set, and data across subjects were related using that laterality, rather than body side. Regional covariance patterns for FDOPA and FDG were derived from principal component analysis (PCA). The results demonstrated hemispheric asymmetries and sex-differences in the striatal FDOPA uptake, which were not seen with FDG. In addition, the PCA analysis identified a positive relationship between a major component in FDOPA uptake (associated with the striatal uptake) and an FDG component, which had positive loadings in the thalamus and the cerebellum. The subject scores for these components correlated positively, and both had a negative association with the clinical severity of the disease. The specific extrastriatal FDG covariance pattern contained the thalamus and the cerebellum, components of the previously reported PD related pattern, but not the striatum. The network correlated with both the severity of clinical symptoms of PD and the severity of nigrostriatal dopaminergic hypofunction. The results indicate that FDG PET, when combined with multivariate network analysis at group-level, can be used as an indicator of PD severity. PMID:16222426

Kaasinen, V; Maguire, R P; Hundemer, H-P; Leenders, K L

2006-03-01

293

In Vivo Measurement of Brain GABA Concentrations by Magnetic Resonance Spectroscopy in Smelters Occupationally Exposed to Manganese  

PubMed Central

Background Exposure to excessive levels of manganese (Mn) is known to induce psychiatric and motor disorders, including parkinsonian symptoms. Therefore, finding a reliable means for early detection of Mn neurotoxicity is desirable. Objectives Our goal was to determine whether in vivo brain levels of ?-aminobutyric acid (GABA), N-acetylaspartate (NAA), and other brain metabolites in male smelters were altered as a consequence of Mn exposure. Methods We used T1-weighted magnetic resonance imaging (MRI) to visualize Mn deposition in the brain. Magnetic resonance spectroscopy (MRS) was used to quantify concentrations of NAA, glutamate, and other brain metabolites in globus pallidus, putamen, thalamus, and frontal cortex from a well-established cohort of 10 male Mn-exposed smelters and 10 male age-matched control subjects. We used the MEGA-PRESS MRS sequence to determine GABA levels in a region encompassing the thalamus and adjacent parts of the basal ganglia [GABA-VOI (volume of interest)]. Results Seven of 10 exposed subjects showed clear T1-hyperintense signals in the globus pallidus indicating Mn accumulation. We found a significant increase (82%; p = 0.014) in the ratio of GABA to total creatine (GABA/tCr) in the GABA-VOI of Mn-exposed subjects, as well as a distinct decrease (9%; p = 0.04) of NAA/tCr in frontal cortex that strongly correlated with cumulative Mn exposure (R = ?0.93; p < 0.001). Conclusions We demonstrated elevated GABA levels in the thalamus and adjacent basal ganglia and decreased NAA levels in the frontal cortex, indicating neuronal dysfunction in a brain area not primarily targeted by Mn. Therefore, the noninvasive in vivo MRS measurement of GABA and NAA may prove to be a powerful tool for detecting presymptomatic effects of Mn neurotoxicity.

Dydak, Ulrike; Jiang, Yue-Ming; Long, Li-Ling; Zhu, He; Chen, Jian; Li, Wen-Mei; Edden, Richard A.E.; Hu, Shuguang; Fu, Xue; Long, Zaiyang; Mo, Xue-An; Meier, Dieter; Harezlak, Jaroslaw; Aschner, Michael; Murdoch, James B.; Zheng, Wei

2011-01-01

294

MR-based hypoxia measures in human glioma.  

PubMed

Hypoxia plays a central role in tumor stem cell genesis and is related to a more malignant tumor phenotype, therapy resistance (e.g. in anti-angiogenic therapies) and radio-insensitivity. Reliable hypoxia imaging would provide crucial metabolic information in the diagnostic work-up of brain tumors. In this study, we applied a novel BOLD-based MRI method for the measurement of relative oxygen extraction fraction (rOEF) in glioma patients and investigated potential benefits and drawbacks. Forty-five glioma patients were examined preoperatively in a pilot study on a 3T MR scanner. rOEF was calculated from quantitative transverse relaxation rates (T2, T2*) and cerebral blood volume (CBV) using a quantitative BOLD approach. rOEF maps were assessed visually and by means of a volume of interest (VOI) analysis. In six cases, MRI-targeted biopsy samples were analyzed using HIF-1?-immunohistochemistry. rOEF maps could be obtained with a diagnostic quality. Focal spots with high rOEF values were observed in the majority of high-grade tumors but in none of the low-grade tumors. VOI analysis revealed potentially hypoxic tumor regions with high rOEF in contrast-enhancing tumor regions as well as in the non-enhancing infiltration zone. Systematic bias was found as a result of non-BOLD susceptibility effects (T2*) and contrast agent leakage affecting CBV. Histological samples demonstrated reasonable correspondence between MRI characteristics and HIF-1?-staining. The presented method of rOEF imaging is a promising tool for the metabolic characterization of human glioma. For the interpretation of rOEF maps, confounding factors must be considered, with a special focus on CBV measurements in the presence of contrast agent leakage. Further validation involving a bigger cohort and extended immuno-histochemical correlation is required. PMID:23918147

Tóth, Vivien; Förschler, Annette; Hirsch, Nuria M; den Hollander, Jürgen; Kooijman, Hendrik; Gempt, Jens; Ringel, Florian; Schlegel, Jürgen; Zimmer, Claus; Preibisch, Christine

2013-11-01

295

PET imaging of brain inflammation during early epileptogenesis in a rat model of temporal lobe epilepsy  

PubMed Central

Background Recently, inflammatory cascades have been suggested as a target for epilepsy therapy. Positron emission tomography (PET) imaging offers the unique possibility to evaluate brain inflammation longitudinally in a non-invasive translational manner. This study investigated brain inflammation during early epileptogenesis in the post-kainic acid-induced status epilepticus (KASE) model with post-mortem histology and in vivo with [18F]-PBR111 PET. Methods Status epilepticus (SE) was induced (N = 13) by low-dose injections of KA, while controls (N = 9) received saline. Translocator protein (TSPO) expression and microglia activation were assessed with [125I]-CLINDE autoradiography and OX-42 immunohistochemistry, respectively, 7 days post-SE. In a subgroup of rats, [18F]-PBR111 PET imaging with metabolite-corrected input function was performed before post-mortem evaluation. [18F]-PBR111 volume of distribution (Vt) in volume of interests (VOIs) was quantified by means of kinetic modelling and a VOI/metabolite-corrected plasma activity ratio. Results Animals with substantial SE showed huge overexpression of TSPO in vitro in relevant brain regions such as the hippocampus and amygdala (P < 0.001), while animals with mild symptoms displayed a smaller increase in TSPO in amygdala only (P < 0.001). TSPO expression was associated with OX-42 signal but without obvious cell loss. Similar in vivo [18F]-PBR111 increases in Vt and the simplified ratio were found in key regions such as the hippocampus (P < 0.05) and amygdala (P < 0.01). Conclusion Both post-mortem and in vivo methods substantiate that the brain regions important in seizure generation display significant brain inflammation during epileptogenesis in the KASE model. This work enables future longitudinal investigation of the role of brain inflammation during epileptogenesis and evaluation of anti-inflammatory treatments.

2012-01-01

296

Abnormal White Matter Integrity in Adolescents with Internet Addiction Disorder: A Tract-Based Spatial Statistics Study  

PubMed Central

Background Internet addiction disorder (IAD) is currently becoming a serious mental health issue around the globe. Previous studies regarding IAD were mainly focused on associated psychological examinations. However, there are few studies on brain structure and function about IAD. In this study, we used diffusion tensor imaging (DTI) to investigate white matter integrity in adolescents with IAD. Methodology/Principal Findings Seventeen IAD subjects and sixteen healthy controls without IAD participated in this study. Whole brain voxel-wise analysis of fractional anisotropy (FA) was performed by tract-based spatial statistics (TBSS) to localize abnormal white matter regions between groups. TBSS demonstrated that IAD had significantly lower FA than controls throughout the brain, including the orbito-frontal white matter, corpus callosum, cingulum, inferior fronto-occipital fasciculus, and corona radiation, internal and external capsules, while exhibiting no areas of higher FA. Volume-of-interest (VOI) analysis was used to detect changes of diffusivity indices in the regions showing FA abnormalities. In most VOIs, FA reductions were caused by an increase in radial diffusivity while no changes in axial diffusivity. Correlation analysis was performed to assess the relationship between FA and behavioral measures within the IAD group. Significantly negative correlations were found between FA values in the left genu of the corpus callosum and the Screen for Child Anxiety Related Emotional Disorders, and between FA values in the left external capsule and the Young's Internet addiction scale. Conclusions Our findings suggest that IAD demonstrated widespread reductions of FA in major white matter pathways and such abnormal white matter structure may be linked to some behavioral impairments. In addition, white matter integrity may serve as a potential new treatment target and FA may be as a qualified biomarker to understand the underlying neural mechanisms of injury or to assess the effectiveness of specific early interventions in IAD.

Qin, Lindi; Zhao, Zhimin; Xu, Jianrong; Lei, Hao

2012-01-01

297

Statin therapy in rheumatoid arthritis: a cost-effectiveness and value-of-information analysis.  

PubMed

HMG-CoA reductase inhibitors (statins) are potentially excellent candidate agents for patients with rheumatoid arthritis (RA). They reduce both cardiovascular risks and RA disease activity. To evaluate the potential long-term effects of statin therapy among patients with RA, and to determine their associated cost effectiveness by incorporating both the cardiovascular and the anti-rheumatic benefits. A Markov decision-analytic model was developed to simulate cardiovascular and RA disease profiles over time. The impact of statin therapy was estimated by adjusting the risk of coronary heart disease (CHD) events and changes in the RA Disease Activity Score (DAS28), based on the results of a randomized trial. The benefits (QALYs) and costs (in year 2005 values) were evaluated from a US payer perspective. A full uncertainty analysis, including a value-of-information (VOI) analysis, was undertaken to evaluate the importance of individual parameters. Using a 10-year time horizon, the additional cost and QALYs of statin therapy were estimated to be USD4690 and 0.44 QALYs, respectively, resulting in an incremental cost-effectiveness ratio (ICER) of USD10 650 per QALY (95% CI 1525, 156 565). The QALY gain associated with statin therapy depended more on the anti-rheumatic effects of statin therapy than on its cardiovascular prevention effect. The VOI analysis found the long-term benefit of statin therapy (i.e. >or=12 months) and the consequent impact on quality of life to be the most uncertain and, therefore, influential parameters. Our analysis indicates that the dual anti-inflammatory/cardiovascular benefits of statins could make this therapy highly cost effective in RA. However, uncertainties remain in the available data, warranting further research on refining the precise RA disease-activity benefits and health-utility changes associated with statin therapy, at least over a 12-month period. PMID:19178122

Bansback, Nick; Ara, Roberta; Ward, Sue; Anis, Aslam; Choi, Hyon K

2009-01-01

298

Return to Venus of Japanese Venus Orbiter AKATSUKI  

NASA Astrophysics Data System (ADS)

Japanese Venus Climate Orbiter 'AKATSUKI' (PLANET-C) was successfully launched at 06:58:22JST on May 21, by H-IIA F17. The malfunction, which happened during the Venus Orbit Insertion (VOI) on 7 Dec, 2010 is as follows. Orbital maneuver engine (OME) was fired 08:49 JST on Dec. 7. 1min. after firing the spacecraft went into the occultation region and we had no telemetry, but we expected to continuous firing for 12min. Recording on the spacecraft told us later that, unfortunately the firing continued just 152sec. and stopped. The reason of the malfunction of the OME was the blocking of check valve on the gas pressure line to push the fuel to the engine. We failed to make the spacecraft the Venus orbiter, and it is rotating the sun with the orbital period of 203 days. Most of the fuel still remains, but the OME was found to be broken. We decided to use only RCS for orbit maneuver and 3 minor maneuvers in November 2012 were successfully done so that AKATSUKI will meet Venus in late 2015. We are considering several scenarios only using RCS for VOI. In the presentation we will show the possible orbits and how we put the spacecraft into those orbits. They have higher apoapsis than we expected in the initial design, but they are still westward and equatorial that is ideal to reveal the mechanism of the super-rotation of the atmosphere, and we think we will be able to achieve the scientific goals which we have been proposing.

Nakamura, M.; Ishii, N.; Abe, T.; Imamura, T.; Yamazaki, A.; Satoh, T.; Suzuki, M.; Ueno, M.; Ohtsuki, S.; Yamada, M.; Ogohara, K.; Uemizu, K.; Hirose, C.; Kawakatsu, Y.; Watanabe, S.; Takahashi, Y.; Iwagami, N.; Taguchi, M.

2012-12-01

299

Role of pharmacoeconomic analysis in R&D decision making: when, where, how?  

PubMed

Pharmacoeconomics is vitally important to drug manufacturers in terms of communicating to external decision-makers (payers, prescribers, patients) the value of their products, achieving regulatory and reimbursement approval and contributing to commercial success. Since development of new drugs is long, costly and risky, and decisions must be made how to allocate considerable research and development (R&D) resources, pharmacoeconomics also has an essential role informing internal decision-making (within a company) during drug development. The use of pharmacoeconomics in early development phases is likely to enhance the efficiency of R&D resource use and also provide a solid foundation for communicating product value to external decision-makers further downstream, increasing the likelihood of regulatory (reimbursement) approval and commercial success. This paper puts the case for use of pharmacoeconomic analyses earlier in the development process and outlines five techniques (clinical trial simulation [CTS], option pricing [OP], investment appraisal [IA], threshold analysis [TA] and value of information [VOI] analysis) that can provide useful input into the design of clinical development programmes, portfolio management and optimal pricing strategy. CTS can estimate efficacy and tolerability profiles before clinical data are available. OP can show the value of different clinical programme designs, sequencing of studies and stop decisions. IA can compare expected net present value (NPV) of different product profiles or study designs. TA can be used to understand development drug profile requirements given partial data. VOI can assist risk management by quantifying uncertainty and assessing the economic viability of gathering further information on the development drug. No amount of pharmacoeconomic data can make a bad drug good; what it can do is enhance the drug developers understanding of the characteristics of that drug. Decision-making, in light of this information, is likely to be better than that without it, whether it leads to faster termination of uneconomic projects or the allocation of more appropriate resources to attractive projects. PMID:15693724

Miller, Paul

2005-01-01

300

Noninvasive image derived heart input function for CMRglc measurements in small animal slow infusion FDG PET studies.  

PubMed

Absolute quantitation of the cerebral metabolic rate for glucose (CMRglc) can be obtained in positron emission tomography (PET) studies when serial measurements of the arterial [(18)F]-fluoro-deoxyglucose (FDG) input are available. Since this is not always practical in PET studies of rodents, there has been considerable interest in defining an image-derived input function (IDIF) by placing a volume of interest (VOI) within the left ventricle of the heart. However, spill-in arising from trapping of FDG in the myocardium often leads to progressive contamination of the IDIF, which propagates to underestimation of the magnitude of CMRglc. We therefore developed a novel, non-invasive method for correcting the IDIF without scaling to a blood sample. To this end, we first obtained serial arterial samples and dynamic FDG-PET data of the head and heart in a group of eight anaesthetized rats. We fitted a bi-exponential function to the serial measurements of the IDIF, and then used the linear graphical Gjedde-Patlak method to describe the accumulation in myocardium. We next estimated the magnitude of myocardial spill-in reaching the left ventricle VOI by assuming a Gaussian point-spread function, and corrected the measured IDIF for this estimated spill-in. Finally, we calculated parametric maps of CMRglc using the corrected IDIF, and for the sake of comparison, relative to serial blood sampling from the femoral artery. The uncorrected IDIF resulted in 20% underestimation of the magnitude of CMRglc relative to the gold standard arterial input method. However, there was no bias with the corrected IDIF, which was robust to the variable extent of myocardial tracer uptake, such that there was a very high correlation between individual CMRglc measurements using the corrected IDIF with gold-standard arterial input results. Based on simulation, we furthermore find that electrocardiogram-gating, i.e. ECG-gating is not necessary for IDIF quantitation using our approach. PMID:23160517

Xiong, Guoming; Paul, Cumming; Todica, Andrei; Hacker, Marcus; Bartenstein, Peter; Böning, Guido

2012-12-01

301

Noninvasive image derived heart input function for CMRglc measurements in small animal slow infusion FDG PET studies  

NASA Astrophysics Data System (ADS)

Absolute quantitation of the cerebral metabolic rate for glucose (CMRglc) can be obtained in positron emission tomography (PET) studies when serial measurements of the arterial [18F]-fluoro-deoxyglucose (FDG) input are available. Since this is not always practical in PET studies of rodents, there has been considerable interest in defining an image-derived input function (IDIF) by placing a volume of interest (VOI) within the left ventricle of the heart. However, spill-in arising from trapping of FDG in the myocardium often leads to progressive contamination of the IDIF, which propagates to underestimation of the magnitude of CMRglc. We therefore developed a novel, non-invasive method for correcting the IDIF without scaling to a blood sample. To this end, we first obtained serial arterial samples and dynamic FDG-PET data of the head and heart in a group of eight anaesthetized rats. We fitted a bi-exponential function to the serial measurements of the IDIF, and then used the linear graphical Gjedde-Patlak method to describe the accumulation in myocardium. We next estimated the magnitude of myocardial spill-in reaching the left ventricle VOI by assuming a Gaussian point-spread function, and corrected the measured IDIF for this estimated spill-in. Finally, we calculated parametric maps of CMRglc using the corrected IDIF, and for the sake of comparison, relative to serial blood sampling from the femoral artery. The uncorrected IDIF resulted in 20% underestimation of the magnitude of CMRglc relative to the gold standard arterial input method. However, there was no bias with the corrected IDIF, which was robust to the variable extent of myocardial tracer uptake, such that there was a very high correlation between individual CMRglc measurements using the corrected IDIF with gold-standard arterial input results. Based on simulation, we furthermore find that electrocardiogram-gating, i.e. ECG-gating is not necessary for IDIF quantitation using our approach.

Xiong, Guoming; Cumming, Paul; Todica, Andrei; Hacker, Marcus; Bartenstein, Peter; Böning, Guido

2012-12-01

302

Assessment of tumour response with 18F-fluorodeoxyglucose positron emission tomography using three-dimensional measures compared to SUVmax—a phantom study  

NASA Astrophysics Data System (ADS)

SUVmax is currently the most common semi-quantitative method of response assessment on FDG PET. By defining the tumour volume of interest (VOI), a measure of total glycolytic volume (TGV) may be obtained. We aimed to comprehensively examine, in a phantom setting, the accuracy of TGV in reflecting actual lesion activity and to compare TGV with SUVmax for response assessment. The algorithms for VOI generation from which TGV was derived included fixed threshold techniques at 50% of maximum (MAX50), 70% of maximum (MAX70), an adaptive threshold of 50% of (maximum + background)/2 (BM50) and a semi-automated iterative region-growing algorithm, GRAB. Comparison with both actual lesion activity and response scenarios was performed. SUVmax correlated poorly with actual lesion activity (r = 0.651) and change in lesion activity (r = 0.605). In a response matrix scenario SUVmax performed poorly when all scenarios were considered, but performed well when only clinically likely scenarios were included. The TGV derived using MAX50 and MAX70 algorithms performed poorly in evaluation of lesion change. The TGV derived from BM50 and GRAB algorithms however performed extremely well in correlation with actual lesion activity (r = 0.993 and r = 0.982, respectively), change in lesion activity (r = 0.972 and r = 0.963, respectively) and in the response scenario matrix. TGVGRAB demonstrated narrow confidence bands when modelled with actual lesion activity. Measures of TGV generated by iterative algorithms such as GRAB show potential for increased sensitivity of metabolic response monitoring compared to SUVmax, which may have important implications for improved patient care.

Boucek, J. A.; Francis, R. J.; Jones, C. G.; Khan, N.; Turlach, B. A.; Green, A. J.

2008-08-01

303

Interactive Dose Shaping - efficient strategies for CPU-based real-time treatment planning  

NASA Astrophysics Data System (ADS)

Conventional intensity modulated radiation therapy (IMRT) treatment planning is based on the traditional concept of iterative optimization using an objective function specified by dose volume histogram constraints for pre-segmented VOIs. This indirect approach suffers from unavoidable shortcomings: i) The control of local dose features is limited to segmented VOIs. ii) Any objective function is a mathematical measure of the plan quality, i.e., is not able to define the clinically optimal treatment plan. iii) Adapting an existing plan to changed patient anatomy as detected by IGRT procedures is difficult. To overcome these shortcomings, we introduce the method of Interactive Dose Shaping (IDS) as a new paradigm for IMRT treatment planning. IDS allows for a direct and interactive manipulation of local dose features in real-time. The key element driving the IDS process is a two-step Dose Modification and Recovery (DMR) strategy: A local dose modification is initiated by the user which translates into modified fluence patterns. This also affects existing desired dose features elsewhere which is compensated by a heuristic recovery process. The IDS paradigm was implemented together with a CPU-based ultra-fast dose calculation and a 3D GUI for dose manipulation and visualization. A local dose feature can be implemented via the DMR strategy within 1-2 seconds. By imposing a series of local dose features, equal plan qualities could be achieved compared to conventional planning for prostate and head and neck cases within 1-2 minutes. The idea of Interactive Dose Shaping for treatment planning has been introduced and first applications of this concept have been realized.

Ziegenhein, P.; Kamerling, C. P.; Oelfke, U.

2014-03-01

304

Quantitative analysis of template-based attenuation compensation in 3D brain PET.  

PubMed

An atlas-guided attenuation correction method was recently proposed for 3D brain positron emission tomography (PET) imaging eliminating the need for acquisition of a patient-specific measured transmission scan. The algorithm was validated through comparison to transmission-based attenuation correction (gold standard) using voxelwise statistical parametric mapping (SPM) analysis of clinical data. In contrast to brain 'activation' studies for which SPM is primarily developed, brain PET research studies often involve absolute quantification. In the preliminary validation study published earlier, there is no validation as to how such quantification can be affected by the two methods as the assessment was carried out by an SPM group analysis alone. It is quite important to demonstrate how the proposed method performs individually, particularly for diagnostic applications or individual quantification. In this study, we assess the quantitative accuracy of this method in clinical setting using automated volume of interest (VOI)-based analysis by means of the commercially available BRASS software. There is a very good correlation (R(2)=0.91) between the atlas-guided and measured transmission-guided attenuation correction techniques and the regression line agreed well with the line of identity (slope=0.96) for the grouped analysis of patient data. The mean relative difference between the two methods for all VOIs across the whole population is 2.3% whereas the maximum difference is less than 7%. No proof of statistically significant differences could be verified for all regions. These encouraging results provide further confidence in the adequacy of the proposed approach demonstrating its performance particularly for research studies or diagnostic applications involving quantification. PMID:17113750

Montandon, Marie-Louise; Zaidi, Habib

2007-01-01

305

Radiation dosimetry of florbetapir F 18  

PubMed Central

Background Florbetapir is one of several 18F-labeled amyloid plaque imaging tracers for positron emission tomography (PET). As the bio-distribution and radiation dose of PET tracers in human research are important for estimating the relative risks and benefits, a study was conducted to obtain this information on florbetapir. Methods Nine cognitively normal subjects (six females and three males, age 58?±?10 years, weight 81?±?17 kg) received an intravenous bolus injection of 395?±?27.9 MBq of florbetapir, and whole-body emission scans were performed over approximately 6 h. Computed tomography scans were acquired for attenuation correction. Volumes of interest (VOIs) for source organs including the brain, liver, lung, heart wall, and vertebrae were defined on the PET images. The VOIs of the gallbladder, urinary bladder, and large and small intestines were also defined. Using reference man organ volumes (ICRP 30), total activity was calculated per organ for each time point. The resultant time-activity curves (TACs) were fitted with constrained exponentials. Kinetic data were entered into OLINDA/EXM software to calculate dose estimates; the dynamic urinary bladder and ICRP 30 GI tract models were employed. The effective dose (ED) for each subject was estimated from the acquired data using the adult model. Results The mean ED determined for nine healthy volunteers was 18.60?±?4.26 ?Sv/MBq or 6.88 mSv for a 370-MBq dose. The organs that received the highest radiation absorbed doses were the gallbladder, upper large intestine, small intestine, liver, and urinary bladder at 143.0?±?80.20, 74.50?±?34.20, 65.50?±?29.60, 64.40?±?22.10, and 27.10?±?11.70 ?Sv/MBq, respectively. Conclusions The ED for florbetapir has been calculated for nine healthy volunteers. At a dose of 370 MBq florbetapir, the total average ED is approximately 6.88 mSv.

2014-01-01

306

Computer-aided detection of breast masses in digital breast tomosynthesis (DBT): improvement of false positive reduction by optimization of object segmentation  

NASA Astrophysics Data System (ADS)

DBT is a promising new imaging modality that may improve the sensitivity and specificity for breast cancer detection. However, DBT could only provide quasi-3D information with limited resolution along the depth (Z) direction because tomosynthesis only has limited angular information for reconstruction. Our purpose of this study is to develop a mass segmentation method for a computer-aided detection system in DBT. A data set of 50 two-view DBTs was collected with a GE prototype system. We reconstructed the DBTs using a simultaneous algebraic reconstruction technique (SART). Mass candidates including true and false masses were identified by 3D gradient field analysis. Two-stage 3D clustering followed by active contour segmentation was applied to a volume of interest (VOI) at each candidate location. We compared a fixed-Z approach, in which the Z dimension of the VOI was pre-determined, to an adaptive-Z approach, in which Z was determined by the object diameter (D) on the X-Y plane obtained from the first-stage clustering. We studied the effect of Z ranging from D to D+8 slices, centered at the central slice, in the second stage. Features were extracted on the individual slices of the segmented 3D object and averaged over all slices for both approaches. Linear discriminant analysis with stepwise feature selection was trained with a leave-one-case-out method to differentiate true from false masses in each feature space. With proper optimization of the adaptive-Z approach, the classification accuracy was significantly improved (p<0.0001) in comparison with the fixed-Z approach. The improved differentiation of true from false masses will be useful for false positive reduction in an automated mass detection system.

Wei, Jun; Chan, Heang-Ping; Sahiner, Berkman; Hadjiiski, Lubomir M.; Helvie, Mark A.; Zhou, Chuan; Lu, Yao

2011-03-01

307

Croissance epitaxiale de GaAs sur substrats de Ge par epitaxie par faisceaux chimiques  

NASA Astrophysics Data System (ADS)

La situation energetique et les enjeux environnementaux auxquels la societe est confrontee entrainent un interet grandissant pour la production d'electricite a partir de l'energie solaire. Parmi les technologies actuellement disponibles, la filiere du photovoltaique a concentrateur solaire (CPV pour concentrator photovoltaics) possede un rendement superieur et mi potentiel interessant a condition que ses couts de production soient competitifs. La methode d'epitaxie par faisceaux chimiques (CBE pour chemical beam epitaxy) possede plusieurs caracteristiques qui la rendent interessante pour la production a grande echelle de cellules photovoltaiques a jonctions multiples a base de semi-conducteurs III-V. Ce type de cellule possede la meilleure efficacite atteinte a ce jour et est utilise sur les satellites et les systemes photovoltaiques a concentrateur solaire (CPV) les plus efficaces. Une des principales forces de la technique CBE se trouve dans son potentiel d'efficacite d'utilisation des materiaux source qui est superieur a celui de la technique d'epitaxie qui est couramment utilisee pour la production a grande echelle de ces cellules. Ce memoire de maitrise presente les travaux effectues dans le but d'evaluer le potentiel de la technique CBE pour realiser la croissance de couches de GaAs sur des substrats de Ge. Cette croissance constitue la premiere etape de fabrication de nombreux modeles de cellules solaires a haute performance decrites plus haut. La realisation de ce projet a necessite le developpement d'un procede de preparation de surface pour les substrats de germanium, la realisation de nombreuses sceances de croissance epitaxiale et la caracterisation des materiaux obtenus par microscopie optique, microscopie a force atomique (AFM), diffraction des rayons-X a haute resolution (HRXRD), microscopie electronique a transmission (TEM), photoluminescence a basse temperature (LTPL) et spectrometrie de masse des ions secondaires (SIMS). Les experiences ont permis de confirmer l'efficacite du procede de preparation de surface et d'identifier les conditions de croissance optimales. Les resultats de caracterisation indiquent que les materiaux obtenus presentent une tres faible rugosite de surface, une bonne qualite cristalline et un dopage residuel relativement important. De plus, l'interface GaAs/Ge possede une faible densite de defauts. Finalement, la diffusion d'arsenic dans le substrat de germanium est comparable aux valeurs trouvees dans la litterature pour la croissance a basse temperature avec les autres procedes d'epitaxie courants. Ces resultats confirment que la technique d'epitaxie par faisceaux chimiques (CBE) permet de produire des couches de GaAs sur Ge de qualite adequate pour la fabrication de cellules solaires a haute performance. L'apport a la communaute scientifique a ete maximise par le biais de la redaction d'un article soumis a la revue Journal of Crystal Growth et la presentation des travaux a la conference Photovoltaics Canada 2010 . Mots-cles : Epitaxie par jets chimiques, Chemical beam epitaxy, CBE, MOMBE, Germanium, GaAs, Ge

Belanger, Simon

308

List of Participants  

NASA Astrophysics Data System (ADS)

Mohab Abou ZeidVrije Universiteit, Brussel Joke AdamKatholieke Universiteit Leuven Nikolas AkerblomMax-Planck-Institut für Physik, München Luis Fernando Alday Utrecht University Stelios Alexandris University of Patras Antonio Amariti Università di Milano-Bicocca Nicola Ambrosetti Université de Neuchâtel Pascal Anastasopoulos Università di Roma Tor Vergata Laura Andrianopoli Enrico Fermi Center Carlo Angelantonj Università di Torino Lilia Anguelova Queen Mary, University of London Daniel AreanUniversidade de Santiago de Compostela Gleb ArutyunovUtrecht University Spyros Avramis NTU Athens—University of Patras Ioannis Bakas University of Patras Subrata Bal Dublin Institute for Advanced Studies Igor Bandos Valencia University Jessica Barrett University of Iceland Marco Baumgartl Eidgenössische Technische Hochschule, Zürich Jacopo Bechi Università di Firenze James Bedford Queen Mary, University of London Jorge Bellorin Universidad Autonoma de Madrid Francesco Benini SISSA, Trieste Eric Bergshoeff Centre for Theoretical Physics, University of Groningen Gaetano BertoldiUniversity of Wales, Swansea Adel Bilal Laboratoire de Physique Théorique, École Normale Superieure, Paris Matthias Blau Université de Neuchâtel Johannes BroedelUniversität Hannover Felix Brümmer Universität Heidelberg Julio Cesar Bueno de Andrade São Paulo State University—UNESP Cliff Burgess McMaster University Agostino Butti Laboratoire de Physique Théorique, École Normale Superieure, Paris Marco Caldarelli Universitat de Barcelona Pablo G Camara Centre de Physique Théorique, École Polytechnique, Palaiseau Joan Camps Universitat de Barcelona Felipe Canoura FernandezUniversidade de Santiago de Compostela Luigi Cappiello Università di Napoli Federico II Luca Carlevaro École Polytechnique, Palaiseau Roberto Casero Centre de Physique Théorique, École Polytechnique, Palaiseau Claudio Caviezel Max-Planck-Institut für Physik, München Alessio Celi Universitat de Barcelona Anna Ceresole Istituto Nazionale di Fisica Nucleare and Università di Torino Kang Sin Choi University of Bonn Michele Cirafici University of Patras Andres Collinucci Katholieke Universiteit Leuven Aldo Cotrone Universitat de Barcelona Ben Craps Vrije Universiteit, Brussel Stefano Cremonesi SISSA, Trieste Gianguido Dall'Agata Padova University Sanjit Das Indian Institute of Technology, Kharagpur Forcella Davide SISSA, Trieste Jose A de Azcarraga Valencia University and Instituto de Fìsica Corpuscular (CSIC-UVEG), Valencia Sophie de BuylInstitut des Hautes Études Scientifiques, Bures-sur-Yvette Jean-Pierre Derendinger Université de Neuchâtel Stephane Detournay Università Degli Studi di Milano Paolo Di Vecchia NORDITA, København Oscar Dias Universitat de Barcelona Vladimir Dobrev Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia Joel Ekstrand Department of Theoretical Physics, Uppsala University Federico Elmetti Università di Milano I Diaconu Eugen University of Craiova Oleg Evnin Vrije Universiteit, Brussel Bo Feng Imperial College, London Livia Ferro Università di Torino Pau Figueras Universitat de Barcelona Raphael Flauger University of Texas at Austin Valentina Forini Università di Perugia Angelos Fotopoulos Università di Torino Denis Frank Université de Neuchâtel Lisa Freyhult Albert-Einstein-Institut, Golm Carlos Fuertes Instituto de Física Teórica, Madrid Matthias Gaberdiel Eidgenössische Technische Hochschule, Zürich Maria Pilar Garcia del Moral Università di Torino Daniel Gerber Instituto de Física Teórica, Madrid Valentina Giangreco Marotta Puletti Uppsala University Joaquim Gomis Universitat de Barcelona Gianluca Grignani Università di Perugia Luca Griguolo Università di Parma Umut Gursoy École Polytechnique, Palaiseau and École Normale Supérieure, Paris Michael Haack Ludwig-Maximilians-Universität, München Troels Harmark Niels Bohr Institute, København Alexander Haupt Imperial College, London Michal Heller Jagiellonian University, Krakow Samuli Hemming University of Iceland Yasuaki Hikida DESY,

2007-11-01

309

Elaboration du Ge mesoporeux et etude de ses proprietes physico-chimiques en vue d'applications photovoltaiques  

NASA Astrophysics Data System (ADS)

Le sujet de cette these porte sur l'elaboration du nouveau nanomateriau par la gravure electrochimique bipolaire (BEE) --- le Ge mesoporeux et sur l'analyse de ses proprietes physico-chimiques en vue de son utilisation dans des applications photovoltaiques. La formation du Ge mesoporeux par gravure electrochimique a ete precedemment rapportee dans la litterature. Cependant, le verrou technologique important des procedes de fabrication existants consistait a obtenir des couches epaisses (superieure a 500 nm) du Ge mesoporeux a la morphologie parfaitement controlee. En effet, la caracterisation physico-chimique des couches minces est beaucoup plus compliquee et le nombre de leurs applications possibles est fortement limite. Nous avons developpe un modele electrochimique qui decrit les mecanismes principaux de formation des pores ce qui nous a permis de realiser des structures epaisses du Ge mesoporeux (jusqu'au 10 mum) ayant la porosite ajustable dans une large gamme de 15% a 60%. En plus, la formation des nanostructures poreuses aux morphologies variables et bien controlees est desormais devenue possible. Enfin, la maitrise de tous ces parametres a ouvert la voie extremement prometteuse vers la realisation des structures poreuses a multi-couches a base de Ge pour des nombreuses applications innovantes et multidisciplinaires grace a la flexibilite technologique actuelle atteinte. En particulier, dans le cadre de cette these, les couches du Ge mesoporeux ont ete optimisees dans le but de realiser le procede de transfert de couches minces d'une cellule solaire a triple jonctions via une couche sacrificielle en Ge poreux. Mots-cles : Germanium meso-poreux, Gravure electrochimique bipolaire, Electrochimie des semi-conducteurs, Report des couches minces, Cellule photovoltaique

Tutashkonko, Sergii

310

Long-term autonomous spectrophotometry applied to the measurement of CO2 at the sea surface on board a drifting buoy  

NASA Astrophysics Data System (ADS)

It is now well accepted that the increase of atmospheric greenhouse effect gases, particularly carbon dioxide, has an important impact on our climatic system, even if the true effect of the development of human industrial activities is not totally assessed. It is then necessary to have a good overall knowledge of the carbon dioxide cycle, and more particularly the fluxes exchanged the three CO2 tanks: atmosphere, ocean, and continental biosphere. Since the ocean is the biggest carbon tank (60 times the atmosphere tank), it constitutes an important potenetial well for the atmospheric CO2. However, the data available show an uncertainty of ca. 30% on the estimated flux. It is then important to assess the quantity of CO2 at the surface of the ocean, and the corresponding atmosphere/ocean flux. The possible future atmospheric CO2 concentration corresponding to different industrial emission scenarii can then be assessed. The method measurement of the CO2 at the sea surface use spectro- photometry of a sensitive dye, housed in a tank which has walls immersed in the sea water. The spectro-photometer especially designed, patented, and build-up by IFP has been developed with special emphasis on high accuracy, rugged construction, ease of operation without maintenance, and calibration over a period of time of over one year. The leading idea was to have as few internal moving parts as possible by the use of fiber optics, and internal calibration by the use of internal reference channels. Ancillary data are also measured. Data is transmitted to the processing center via ARGOS. The equipment described is part of the EUREKA CARIOCA project (EU 819), supported by the French Ministere de l'Enseignement Superieur et de la Recherche (93 W 0011) and UK's DTI. The partners are: LODYC, LGE, INSU, SERPE-IESM (France), and Chelsea Instruments (UK).

Wadsworth, Alain; Delignieres, R.; Durand, Ch.

1995-09-01

311

Simulation d'ecoulements internes compressibles laminaires et turbulents par une methode d'elements finis  

NASA Astrophysics Data System (ADS)

Ce travail consiste en la simulation numerique des ecoulements internes compressibles bidimensionnels laminaires et turbulents. On s'interesse, particulierement, aux ecoulements dans les ejecteurs supersoniques. Les equations de Navier-Stokes sont formulees sous forme conservative et utilisent, comme variables independantes, les variables dites enthalpiques a savoir: la pression statique, la quantite de mouvement et l'enthalpie totale specifique. Une formulation variationnelle stable des equations de Navier-Stokes est utilisee. Elle est base sur la methode SUPG (Streamline Upwinding Petrov Galerkin) et utilise un operateur de capture des forts gradients. Un modele de turbulence, pour la simulation des ecoulements dans les ejecteurs, est mis au point. Il consiste a separer deux regions distinctes: une region proche de la paroi solide, ou le modele de Baldwin et Lomax est utilise et l'autre, loin de la paroi, ou une formulation nouvelle, basee sur le modele de Schlichting pour les jets, est proposee. Une technique de calcul de la viscosite turbulente, sur un maillage non structure, est implementee. La discretisation dans l'espace de la forme variationnelle est faite a l'aide de la methode des elements finis en utilisant une approximation mixte: quadratique pour les composantes de la quantite de mouvement et de la vitesse et lineaire pour le reste des variables. La discretisation temporelle est effectuee par une methode de differences finies en utilisant le schema d'Euler implicite. Le systeme matriciel, resultant de la discretisation spatio-temporelle, est resolu a l'aide de l'algorithme GMRES en utilisant un preconditionneur diagonal. Les validations numeriques ont ete menees sur plusieurs types de tuyeres et ejecteurs. La principale validation consiste en la simulation de l'ecoulement dans l'ejecteur teste au centre de recherche NASA Lewis. Les resultats obtenus sont tres comparables avec ceux des travaux anterieurs et sont nettement superieurs concernant les ecoulements turbulents dans les ejecteurs.

Rebaine, Ali

1997-08-01

312

Extranodal NK/T-cell lymphoma, nasal type, includes cases of natural killer cell and ??, ??, and ??/?? T-cell origin: a comprehensive clinicopathologic and phenotypic study.  

PubMed

Extranodal NK/T-cell lymphoma (ENKTL), nasal type, may be of NK or T-cell origin; however, the proportion of T-ENKTLs and whether they are of ?? or ?? type remains uncertain. To elucidate the cell of origin and detailed phenotype of ENKTL and assess any clinicopathologic associations, 67 cases of ENKTL from Thailand were investigated, together with 5 ?? enteropathy-associated T-cell lymphomas (EATLs) for comparison. In all, 70% of the ENKTL were T-cell receptor (TCR) ?,? and, in cases tested, ? negative (presumptive NK origin); 5% were TCR ??, 3% were TCR ??, 1% were TCR ??/??, and 21% were indeterminate. Out of 17 presumptive NK-ENKTLs tested, 3 had clonal TCR rearrangements. All cases were EBV and TIA-1; >85% were positive for CD3, CD2, granzyme B, pSTAT3, and Lsk/MATK; and all were CD16. Presumptive NK-ENKTLs had significantly more frequent CD56 (83% vs. 33%) and CXCL13 (59% vs. 0%) but less frequent PD-1 (0% vs. 40%) compared with T-ENKTLs. Of the NK-ENKTLs, 38% were Oct-2 compared with 0% of T-ENKTLs, and 54% were IRF4/MUM1 compared with 20% of T-ENKTLs. Only ?? T-ENKTLs were CD5. Intestinal ENKTLs were EBV and had significantly more frequent CD30, pSTAT3, and IRF4/MUM1 expression but less frequent CD16 compared with ?? EATL. Significant adverse prognostic indicators included a primary non-upper aerodigestive tract site, high stage, bone marrow involvement, International Prognostic Index ?2, lack of radiotherapy, Ki67 >40%, and CD25 expression. The upper aerodigestive tract ENKTLs of T-cell origin compared with those of presumptive NK origin showed a trend for better survival. Thus, at least 11% of evaluable ENKTLs are of T-cell origin. Although T-ENKTLs have phenotypic and some possible clinical differences, they share many similarities with ENKTLs that lack TCR expression and are distinct from intestinal ?? EATL. PMID:22314189

Pongpruttipan, Tawatchai; Sukpanichnant, Sanya; Assanasen, Thamathorn; Wannakrairot, Pongsak; Boonsakan, Paisarn; Kanoksil, Wasana; Kayasut, Kanita; Mitarnun, Winyou; Khuhapinant, Archrob; Bunworasate, Udomsak; Puavilai, Teeraya; Bedavanija, Anan; Garcia-Herrera, Adriana; Campo, Elias; Cook, James R; Choi, John; Swerdlow, Steven H

2012-04-01

313

The Value of Information: Assessing the Ability of Electrical Resistivity to Detect CO2 Leakage in a Shallow Aquifer  

NASA Astrophysics Data System (ADS)

This study demonstrates a methodology for evaluating the value of electrical resistivity data to detect CO2 leakage in a shallow groundwater aquifer. This methodology adopts the value of information (VOI) metric from the field of decision analysis. We consider a stakeholder's decision of whether or not to remediate the aquifer, given that they are uncertain whether or not a CO2 leak has occurred from a deep storage source through a well-bore into the shallow aquifer and what the impact of that leak would be. Two themes of uncertainty are needed for VOI studies. The first is related to the uncertain state of the subsurface, which is directly related to the outcome of the decision. In our example, it is uncertain whether or not the shallow groundwater has been impacted by CO2 leakage. The impact may be determined by the existence of depressed pH or elevated TDS (total dissolved solids) plume. We utilize results from a previous work that investigated uncertainty quantification of spatial heterogeneity and leakage rates (Mansoor et al, 2011). Therefore, we have a comprehensive suite of 713 simulations that represent our uncertainty regarding the existence and extent of a CO2 plume. Given certain TDS and pH thresholds, the simulations are categorized into two groups: impacted (a plume exists) or not impacted (no plume) at time=50 years. The second theme is related to the information's accuracy to inform us about the existence of a plume (e.g. the state of the subsurface directly relevant to the decision). The uncertainty of the information is measured by the data likelihood and is used to determine the value of imperfect information. For this demonstration, we consider how electrical resistivity data can detect the existence of pH plumes (due to the dissolution of CO2) and TDS (due to the accompanying brine leakage). The pH and TDS output from the 713 simulations are used to determine the electrical resistivity at time = 0 and time=50 years. An empirical method is used to compare the time=0 and time=50 resistivities: the geometric log mean ratio (GLMR) of the 2 data sets is calculated (Daily et al, 2004). This requires only the forward response be calculated at the 2 different times. The GLMR is used as a sensitivity measure, representing how much the electrical resistivity would change given the conditions of the aquifer. The likelihood of electrical resistivity to detect the presence of a plume is estimated by comparing the GLMR and the category (plume or no plume) for all the 713 simulations. Electrical resistivity forward models were calculated for two acquisition configurations: surface electrodes only and surface-to-borehole. For the surface acquisition, a GLMR >0.05 exclusively identifies impacted simulations. Whereas GLMR <0.05 give a more ambiguous message: both simulations that are impacted and not have GMLR<0.05. The degree of this ambiguity changes with different definitions of the plume (i.e. pH and TDS thresholds). Surface-to-borehole forward models were performed for a borehole located 200m from the leaky well. Results show that surface-to-borehole resistivity data is more reliable at distinguishing between impacted and non-impacted simulations, and therefore the VOI is higher than for surface electrodes alone. Prepared by LLNL under Contract No. DE-AC52-07NA27344.

Trainor Guitton, W. J.; Yang, X.; Mansoor, K.; Ramirez, A. L.; Sun, Y.; Carroll, S.

2012-12-01

314

A decision tree model to estimate the value of information provided by a groundwater quality monitoring network  

NASA Astrophysics Data System (ADS)

Groundwater contaminated with nitrate poses a serious health risk to infants when this contaminated water is used for culinary purposes. To avoid this health risk, people need to know whether their culinary water is contaminated or not. Therefore, there is a need to design an effective groundwater monitoring network, acquire information on groundwater conditions, and use acquired information to inform management options. These actions require time, money, and effort. This paper presents a method to estimate the value of information (VOI) provided by a groundwater quality monitoring network located in an aquifer whose water poses a spatially heterogeneous and uncertain health risk. A decision tree model describes the structure of the decision alternatives facing the decision-maker and the expected outcomes from these alternatives. The alternatives include (i) ignore the health risk of nitrate-contaminated water, (ii) switch to alternative water sources such as bottled water, or (iii) implement a previously designed groundwater quality monitoring network that takes into account uncertainties in aquifer properties, contaminant transport processes, and climate (Khader, 2012). The VOI is estimated as the difference between the expected costs of implementing the monitoring network and the lowest-cost uninformed alternative. We illustrate the method for the Eocene Aquifer, West Bank, Palestine, where methemoglobinemia (blue baby syndrome) is the main health problem associated with the principal contaminant nitrate. The expected cost of each alternative is estimated as the weighted sum of the costs and probabilities (likelihoods) associated with the uncertain outcomes resulting from the alternative. Uncertain outcomes include actual nitrate concentrations in the aquifer, concentrations reported by the monitoring system, whether people abide by manager recommendations to use/not use aquifer water, and whether people get sick from drinking contaminated water. Outcome costs include healthcare for methemoglobinemia, purchase of bottled water, and installation and maintenance of the groundwater monitoring system. At current methemoglobinemia and bottled water costs of 150/person and 0.6/baby/day, the decision tree results show that the expected cost of establishing the proposed groundwater quality monitoring network exceeds the expected costs of the uninformed alternatives and there is no value to the information the monitoring system provides. However, the monitoring system will be preferred to ignoring the health risk or using alternative sources if the methemoglobinemia cost rises to 300/person or the bottled water cost increases to 2.3/baby/day. Similarly, the monitoring system has value if the system can more accurately report actual aquifer concentrations and the public more fully abides by manager recommendations to use/not use the aquifer. The system also has value if it will serve a larger population or if its installation costs can be reduced, for example using a smaller number of monitoring wells. The VOI analysis shows how monitoring system design, accuracy, installation and operating costs, public awareness of health risks, costs of alternatives, and demographics together affect the value of implementing a system to monitor groundwater quality.

Khader, A. I.; Rosenberg, D. E.; McKee, M.

2013-05-01

315

The pathology of head and neck tumors: mucosal melanomas, part 13.  

PubMed

Pigmented lesions, including melanomas, of the mucous membranes of the head and neck are far outnumbered by their counterparts in the skin. This relative dearth is partially responsible for the fact that scientific inquiry into mucosal melanomas has not kept pace with the advances in knowledge of the pathogenesis of cutaneous melanomas and their diagnosis and treatment. Integral to these latter advances have been the refinements in clinical and histologic classification and clinicopathologic correlations with quantitative evaluation of melanomas of skin-enhancements that up to now have been singularly lacking for mucosal melanomas. This report acknowledges this slowness in progress, present recommendations for purifying the nomenclature of pigmented lesions of the mucosae, and at the same time, also notes the poorer prognosis for melanomas of the upper aerodigestive tracts, as a group, when compared with cutaneous melanomas. Only prospective studies will answer the question of whether the poor prognosis is intrinsic to these mucosal melanomas or whether delay in detection and removal are responsible. PMID:7096100

Batsakis, J G; Regezi, J A; Solomon, A R; Rice, D H

1982-01-01

316

Aspects of nitrogen dioxide toxicity in environmental urban concentrations in human nasal epithelium  

SciTech Connect

Cytotoxicity and genotoxicity of nitrogen dioxide (NO{sub 2}) as part of urban exhaust pollution are widely discussed as potential hazards to human health. This study focuses on toxic effects of NO{sub 2} in realistic environmental concentrations with respect to the current limit values in a human target tissue of volatile xenobiotics, the epithelium of the upper aerodigestive tract. Nasal epithelial cells of 10 patients were cultured as an air-liquid interface and exposed to 0.01 ppm NO{sub 2}, 0.1 ppm NO{sub 2}, 1 ppm NO{sub 2}, 10 ppm NO{sub 2} and synthetic air for half an hour. After exposure, genotoxicity was evaluated by the alkaline single-cell microgel electophoresis (Comet) assay and by induction of micronuclei in the micronucleus test. Depression of proliferation and cytotoxic effects were determined using the micronucleus assay and trypan blue exclusion assay, respectively. The experiments revealed genotoxic effects by DNA fragmentation starting at 0.01 ppm NO{sub 2} in the Comet assay, but no micronucleus inductions, no changes in proliferation, no signs of necrosis or apoptosis in the micronucleus assay, nor did the trypan blue exclusion assay show any changes in viability. The present data reveal a possible genotoxicity of NO{sub 2} in urban concentrations in a screening test. However, permanent DNA damage as indicated by the induction of micronuclei was not observed. Further research should elucidate the effects of prolonged exposure.

Koehler, C.; Ginzkey, C.; Friehs, G.; Hackenberg, S.; Froelich, K.; Scherzed, A.; Burghartz, M.; Kessler, M. [Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg (Germany); Kleinsasser, N., E-mail: Kleinsasser_N@klinik.uni-wuerzburg.d [Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Wuerzburg (Germany)

2010-06-01

317

Curcumin and Other Polyphenolic Compounds in Head and Neck Cancer Chemoprevention  

PubMed Central

Despite clear results of observational studies linking a diet rich in fruits and vegetables to a decreased cancer risk, large interventional trials evaluating the impact of dietary micronutrient supplementation, mostly vitamins, could not show any beneficial effects. Today it has become clear that a single micronutrient, given in supernutritional doses, cannot match cancer preventive effects of whole fruits and vegetables. In this regard polyphenols came into focus, not only because of their antioxidant potential but also because of their ability to interact with molecular targets within the cells. Because polyphenols occur in many foods and beverages in high concentration and evidence for their anticancer activity is best for tissues they can come into direct contact with, field cancerization predestines upper aerodigestive tract epithelium for cancer chemoprevention by polyphenols. In this paper, we summarize cancer chemopreventive attempts with emphasis on head and neck carcinogenesis and discuss some methodological issues. We present data regarding antimutagenic effects of curcumin and epigallocatechin-3-gallate in human oropharyngeal mucosa cultures exposed to cigarette smoke condensate.

Baumeister, Philipp; Reiter, Maximilian; Harreus, Ulrich

2012-01-01

318

Probe-based confocal laser endomicroscopy in head and neck malignancies: early preclinical experience  

NASA Astrophysics Data System (ADS)

Background: Malignancies of the upper aerodigestive tract (UADT) are conventionally diagnosed by white light endoscopy, biopsy and histopathology. Probe-based Confocal Laser Endomicroscopy (pCLE) is a novel non-invasive technique which offers in vivo surface and sub-surface imaging of tissue. It produces pictures of cellular architecture comparable to histology without the need for biopsy. It has already been successfully used in different clinical subspecialties to help in the diagnosis and treatment planning of inflammatory and neoplastic diseases. PCLE needs to be used in combination with specific or non-specific contrast agents. In this study we evaluated the potential use of pCLE in combination with non-specific and specific contrast agents to distinguish between healthy mucosa and invasive carcinoma. Methods: Tissue samples from healthy mucosa and squamous cell carcinoma of the head and neck were taken during surgery. After topical application of three different contrast agents, samples were examined using different pCLE-probes and a Confocal Laser Scanning Microscope (CLSM). Images were then compared to the corresponding histological slides and cryosections. Results: Initial results show that pCLE in combination with fluorophores allows visualization of cellular and structural components. Imaging of different layers was possible using three distinct pCLEprobes. Conclusion: pCLE is a promising non-invasive technique that may be a useful adjunct in the evaluation, diagnosis and treatment planning of head and neck malignancies.

Englhard, Anna; Girschick, Susanne; Mack, Brigitte; Volgger, Veronika; Gires, Oliver; Conderman, Christian; Stepp, Herbert; Betz, Christian Stephan

2013-06-01

319

Alcohol, DNA Methylation, and Cancer  

PubMed Central

Cancer is one of the most significant diseases associated with chronic alcohol consumption, and chronic drinking is a strong risk factor for cancer, particularly of the upper aerodigestive tract, liver, colorectum, and breast. Several factors contribute to alcohol-induced cancer development (i.e., carcinogenesis), including the actions of acetaldehyde, the first and primary metabolite of ethanol, and oxidative stress. However, increasing evidence suggests that aberrant patterns of DNA methylation, an important epigenetic mechanism of transcriptional control, also could be part of the pathogenetic mechanisms that lead to alcohol-induced cancer development. The effects of alcohol on global and local DNA methylation patterns likely are mediated by its ability to interfere with the availability of the principal biological methyl donor, S-adenosylmethionine (SAMe), as well as pathways related to it. Several mechanisms may mediate the effects of alcohol on DNA methylation, including reduced folate levels and inhibition of key enzymes in one-carbon metabolism that ultimately lead to lower SAMe levels, as well as inhibition of activity and expression of enzymes involved in DNA methylation (i.e., DNA methyltransferases). Finally, variations (i.e., polymorphisms) of several genes involved in one-carbon metabolism also modulate the risk of alcohol-associated carcinogenesis.

Varela-Rey, Marta; Woodhoo, Ashwin; Martinez-Chantar, Maria-Luz; Mato, Jose M.; Lu, Shelly C.

2013-01-01

320

Aggressive mature natural killer cell neoplasms: from epidemiology to diagnosis.  

PubMed

Mature natural killer (NK) cell neoplasms are classified by the World Health Organization into NK/T cell lymphoma, nasal type (NKTCL), aggressive NK-cell leukemia (ANKCL) and chronic lymphoproliferative disorders of NK-cells, the latter being considered provisionally. NKTCL and ANKCL are rare diseases, with higher prevalence in Asia, Central and South America. Most NKTCL present extranodal, as a destructive tumor affecting the nose and upper aerodigestive tract (nasal NKTCL) or any organ or tissue (extranasal NKTCL) whereas ANKCL manifests as a systemic disease with multiorgan involvement and naturally evolutes to death in a few weeks. The histopathological hallmark of these aggressive NK-cell tumors is a polymorphic neoplastic infiltrate with angiocentricity, angiodestruction and tissue necrosis. The tumor cells have cytoplasmatic azurophilic granules and usually show a CD45(+bright), CD2(+), sCD3(-), cytCD3epsilon(+), CD56(+bright), CD16(?/+), cytotoxic granules molecules(+) phenotype. T-cell receptor genes are in germ-line configuration. Epstein-Barr virus (EBV) -encoded membrane proteins and early region EBV RNA are usually detected on lymphoma cells, with a pattern suggestive of a latent viral infection type II. Complex chromosomal abnormalities are frequent and loss of chromosomes 6q, 11q, 13q, and 17p are recurrent aberrations. The rarity of the NK-cell tumors limits our ability to standardize the procedures for the diagnosis and clinical management and efforts should be made to encourage multi-institutional registries. PMID:23816348

Lima, Margarida

2013-01-01

321

Swallowing and voice effects of Lee Silverman Voice Treatment (LSVT(R)): a pilot study  

PubMed Central

Objective: To define the effects of Lee Silverman Voice Treatment (LSVT® on swallowing and voice in eight patients with idiopathic Parkinson's disease. Methods: Each patient received a modified barium swallow (MBS) in addition to voice recording before and after 1 month of LSVT®. Swallowing motility disorders were defined and temporal measures of the swallow were completed from the MBS. Voice evaluation included measures of vocal intensity, fundamental frequency, and the patient's perception of speech change. Results: before LSVT®, the most prevalent swallowing motility disorders were oral phase problems including reduced tongue control and strength. Reduced tongue base retraction resulting in residue in the vallecula was the most common disorder in the pharyngeal stage of the swallow. Oral transit time (OTT) and pharyngeal transit time (PTT) were prolonged. After LSVT®, there was an overall 51% reduction in the number of swallowing motility disorders. Some temporal measures of swallowing were also significantly reduced as was the approximate amount of oral residue after 3 ml and 5 ml liquid swallows. Voice changes after LSVT® included a significant increase in vocal intensity during sustained vowel phonation as well as during reading. Conclusions: LSVT® seemingly improved neuromuscular control of the entire upper aerodigestive tract, improving oral tongue and tongue base function during the oral and pharyngeal phases of swallowing as well as improving vocal intensity.

El Sharkawi, A; Ramig, L; Logemann, J; Pauloski, B; Rademaker, A; Smith, C; Pawlas, A; Baum, S; Werner, C

2002-01-01

322

Changing Trends in Oesophageal Endoscopy: A Systematic Review of Transnasal Oesophagoscopy  

PubMed Central

The safety, efficacy, and economic implications of using transnasal oesophagoscopy (TNE) are compared with conventional rigid or flexible oesophagoscopy for oesophageal disorders in otorhinolaryngology (ORL) clinics in this systematic review. Eleven electronic databases were searched for articles on transnasal oesophagoscopy. A total of 67 relevant titles were identified and 39 abstracts were screened of which 17 full- text articles were included in this report. There was fair level of evidence to suggest that TNE was effective for screening examination in patients with dysphagia, globus pharyngeus, and reflux symptoms and for detection of metachronous oesophageal carcinoma. TNE can also be used to biopsy suspicious lesions in the upper aerodigestive tract, placement of wireless pH capsule, transnasal balloon dilation of the oesophagus, secondary tracheoesophageal puncture, and management of foreign bodies. TNE was well tolerated and can be safely performed in an office setting with topical anaesthesia. Complications associated with TNE were mild and uncommon. There was evidence to suggest potential cost savings by performing TNE in the office setting compared with conventional investigation and examination for dysphagia. TNE may lead to a change in practice from investigation and treatment in the operating theatre or day care center to an office-based practice.

Sabirin, Junainah; Abd Rahman, Maharita; Rajan, Philip

2013-01-01

323

Obesity and cancer: Mendelian randomization approach utilizing the FTO genotype  

PubMed Central

Background Obesity is a risk factor for several cancers although appears to have an inverse association with cancers strongly related to tobacco. Studying obesity is difficult due to numerous biases and confounding. Methods To avoid these biases we used a Mendelian randomization approach incorporating an analysis of variants in the FTO gene that are strongly associated with BMI levels among 7000 subjects from a study of lung, kidney and upper-aerodigestive cancer. Results The FTO A allele which is linked with increased BMI was associated with a decreased risk of lung cancer (allelic odds ratio (OR) = 0.92, 95% confidence interval (CI) 0.84–1.00). It was also associated with a weak increased risk of kidney cancer, which was more apparent before the age of 50 (OR = 1.44, CI 1.09–1.90). Conclusion Our results highlight the potential for genetic variation to act as an unconfounded marker of environmentally modifiable factors, and offer the potential to obtain estimates of the causal effect of obesity. However, far larger sample sizes than studied here will be required to undertake this with precision.

Brennan, Paul; McKay, James; Moore, Lee; Zaridze, David; Mukeria, Anush; Szeszenia-Dabrowska, Neonilia; Lissowska, Jolanta; Rudnai, Peter; Fabianova, Eleonora; Mates, Dana; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Chow, Wong-Ho; Rothman, Nathaniel; Chabrier, Amelie; Gaborieau, Valerie; Timpson, Nic; Hung, Rayjean J; Smith, George Davey

2009-01-01

324

Diagnosis of second primary tumor and long-term survival after single initial triple endoscopy in patients with head and neck cancer.  

PubMed

Patients with squamous cell carcinoma of the upper aerodigestive tract (UADT) have a high risk of developing second primary tumors (SPTs). Most of the studies concerning triple endoscopy (laryngoscopy, digestive tract endoscopy and bronchoscopy) describe the frequency and stage of the SPT, but not its impact on survival. This study is a matched pair analysis that included patients with squamous cell carcinoma of the UADT who were subjected to a triple endoscopy before the first treatment, matched with patients who did not undergo triple endoscopy. One hundred and thirty-five patients were included in each group. The diagnosis of an SPT was more frequent in the initial triple endoscopy group than in the control group (34 and 20 cases, respectively). In the initial triple endoscopy group, 50.0 % of these tumors were diagnosed simultaneously, whereas in the control, only 5.0 %. No significant differences in the survival rates or in clinical stage of the SPTs were found in the two groups. There was no difference in the clinical stage of the SPT and the survival rates of the patient groups who underwent triple endoscopy at the initial evaluation and those subjected to only a routine evaluation and follow-up. PMID:24136478

Priante, Antonio Vitor Martins; Gross, Jefferson Luiz; Sztokfisz, Claudia Zitron; Nishimoto, Inês Nobuko; Kowalski, Luiz Paulo

2014-08-01

325

 

PubMed Central

SUMMARY At present, it is difficult to identify a gold standard for endoscopic staging of laryngeal cancer, especially considering the large number of endoscopic instruments available. We have coined the term multistep endoscopy to describe a method for staging laryngeal precancerous and neoplastic lesions that sequentially uses several endoscopic tools including high definition white light endoscopy (HDTV), stroboscopy and autofluorescence endoscopy. During the period from November 2007 to November 2009, 140 patients with a suspect laryngeal lesion underwent multistep endoscopy at the Department of Otorhinolaryngology at Martini Hospital in Turin. All patients were subjected to a series of endoscopic examinations in indirect laryngoscopy (white light endoscopy coupled to a HDTV camera, laryngostroboscopy, indirect autofluorescence) followed by white light endoscopy coupled to a HDTV camera and autofluorescence in direct microlaryngoscopy. The aim of the present prospective study was to evaluate the utility of multistep endoscopy in the diagnostic work-up of laryngeal lesions. Multistep endoscopy showed a higher sensitivity and "biological" predictive value in early cancer and precancerous lesions of the larynx (sensitivity, 97.9%; specificity, 90.5%) compared to individual endoscopic tools. It allows for better therapeutic planning of superficial lesions and more accurate orientation when performing mapping biopsies on diffuse lesions. In our opinion, more widespread use of indirect autofluorescence endoscopy during follow-up may be warranted to search for synchronous/metachronous second tumours of the upper aerodigestive tract.

CROSETTI, E.; PILOLLI, F.; SUCCO, G.

2012-01-01

326

Nicotine-derived N-nitrosamines (TSNA) and their relevance in tobacco carcinogenesis.  

PubMed

Biochemical studies and bioassays support the concept that the increased risk for cancer of the oral cavity in snuff dippers and cancer of the lung, upper aerodigestive tract, and pancreas in smokers is most likely associated with the exposure to tobacco-specific N-nitrosamines. The doses of TSNA required to induce tumors in the oral cavity in rats and tumors in the lungs of rats and hamsters are comparable to the total doses of TSNA to which a long-term snuff dipper, respectively a cigarette smoker, are exposed over 4 decades. The carcinogenic NNN and NNK are metabolized to highly reactive electrophiles which react with nucleophilic centers of DNA and with proteins. The DNA-adducts are known to cause miscoding which can activate K-ras proto-oncogenes. K-ras oncogenes have been detected in adenocarcinomas of the lung of smokers. TSNA also form globin adducts in the blood of laboratory animals as well as of snuff dippers and smokers. Such adducts are currently being evaluated for their significance as biochemical markers of exposure to TSNA. These biomarkers may also serve as indicators for the possible endogenous formation of TSNA in tobacco chewers and smokers. Additional research needs in TSNA carcinogenesis include the development of modified methods for the reduction of TSNA in tobacco and smoke, inhibition of TSNA carcinogenesis by nutrients and micro-nutrients and the testing of chemopreventive agents. PMID:2069715

Hoffmann, D; Rivenson, A; Chung, F L; Hecht, S S

1991-01-01

327

Current management of nasal NK/T-cell lymphoma.  

PubMed

Nasal natural killer (NK)/T-cell lymphoma--classified as extranodal NK/T-cell lymphoma (ENKTL), nasal type, by the World Health Organization--is a non-Hodgkin lymphoma that is almost always associated with Epstein-Barr virus. Up to 75% of ENKTL cases occur in the upper aerodigestive tract, primarily the nasal cavity. It is the most common type of peripheral T-cell lymphoma in many Asian countries. Histologic diagnosis is essential, and staging consists of bilateral bone marrow biopsy and imaging of the neck, thorax, abdomen, and pelvis. There is a marked dichotomy in treatment and survival between localized and disseminated disease. Since disease incidence is rare even in prevalent areas, experience is limited and most treatment protocols are consensus-guided. ENKTL is both chemosensitive and radiosensitive. Early-stage, localized nasal disease is highly curable with combination therapy, but the optimal dose, combination, and sequence of radiotherapy and chemotherapy are still undefined. For patients with disseminated and extranasal disease, either at initial presentation or at relapse, the prognosis is poor. For disseminated and refractory cases, the 5-year survival rate is below 10%, and better methods of treatment are needed. PMID:20464847

Au, Wing Y

2010-04-15

328

Estimating the optimal threshold for a diagnostic biomarker in case of complex biomarker distributions  

PubMed Central

Background Estimating the optimal threshold (and especially the confidence interval) of a quantitative biomarker to be used as a diagnostic test is essential for medical decision-making. This is often done with simple methods that are not always reliable. More advanced methods work well but only for biomarkers with very simple distributions. In fact, biomarker distributions are often complex because of a natural heterogeneity in marker expression and other heterogeneities due to various disease stages, laboratory equipments, etc. Methods are required to estimate a biomarker optimal threshold in case of heterogeneity and complex distributions. Methods A previously described Bayesian method developed for normally distributed biomarkers is applied to two flexible distributions; namely, a Student-t and a mixture of Dirichlet processes. Here, numerical studies assess the adequacy of the previous method with both distributions. Two applications are presented: the diagnosis of treatment failure after prostate cancer treated by ultrasound and the early diagnosis of cancers of the upper aerodigestive tract. Results Bayesian inference provided reliable credible intervals in terms of bias and coverage probability. The two distributions analysed gave meaningful clinical interpretations in both applications. Conclusions Reliable methods can be used to estimate a biomarker optimal threshold, even in case of complex distributions.

2014-01-01

329

When and where does rheumatoid arthritis begin?  

PubMed

The major strides accomplished in elucidating the pathophysiology of rheumatoid arthritis (RA) have translated into therapeutic breakthroughs in clinical practice. However, currently available treatments work only for as long as they are taken. The development of curative treatments will probably require a better understanding of the earliest phases of RA and perhaps the identification of the etiological factors, which are probably numerous. These objectives are being pursued in studies of preclinical RA. The literature review presented herein indicates that the immunological conflict probably originates outside the joints, at mucous membrane sites and, more specifically, in the upper aerodigestive tract. The preclinical phase of RA can last for many years, and some patients probably never progress to arthritis. An immunological conflict develops then spins out of control, causing increases in autoantibody titers and subsequently in levels of serum markers for inflammation, before the development of the first joint symptoms. Improved knowledge of the preclinical phase, together with information from genetic markers, will allow the identification of profiles associated with susceptibility to RA and perhaps, in the future, the development of preventive strategies. PMID:23177913

Schaeverbeke, Thierry; Truchetet, Marie-Élise; Richez, Christophe

2012-12-01

330

Insights from Studies with Oral Cleft Genes Suggest Associations between WNT-pathway Genes and Risk of Oral Cancer  

PubMed Central

Oral squamous cell carcinoma (OSCC) accounts for more than 90% of the malignant neoplasms that arise in the mucosa of the upper aerodigestive tract. Recent studies of cleft lip/palate have shown the association of genes involved in cancer. WNT pathway genes have been associated with several types of cancer and recently with cleft lip/palate. To investigate if genes associated with cleft lip/palate were also associated with oral cancer, we genotyped 188 individuals with OSCC and 225 control individuals for markers in AXIN2, AXIN1, GSK3?, WNT3A, WNT5A, WNT8A, WNT11, WNT3, and WNT9B. Statistical analysis was performed with PLINK 1.06 software to test for differences in allele frequencies of each polymorphism between cases and controls. We found association of SNPs in GSK3B (p = 0.0008) and WNT11 (p = 0.03) with OSCC. We also found overtransmission of GSK3B haplotypes in OSCC cases. Expression analyses showed up-regulation of WNT3A, GSK3B, and AXIN1 and down-regulation of WNT11 in OSCC in comparison with control tissues (P < 0.001). Additional studies should focus on the identification of potentially functional variants in these genes as contributors to human clefting and oral cancer.

Andrade Filho, P.A.; Letra, A.; Cramer, A.; Prasad, J.L.; Garlet, G.P.; Vieira, A.R.; Ferris, R.L.; Menezes, R.

2011-01-01

331

Traditional and modern uses of natural honey in human diseases: a review.  

PubMed

Honey is a by-product of flower nectar and the upper aero-digestive tract of the honey bee, which is concentrated through a dehydration process inside the bee hive. Honey has a very complex chemical composition that varies depending on the botanical source. It has been used both as food and medicine since ancient times. Human use of honey is traced to some 8000 years ago as depicted by Stone Age paintings. In addition to important role of natural honey in the traditional medicine, during the past few decades, it was subjected to laboratory and clinical investigations by several research groups and it has found a place in modern medicine. Honey has been reported to have an inhibitory effect on around 60 species of bacteria, some species of fungi and viruses. Antioxidant capacity of honey is important in many disease conditions and is due to a wide range of compounds including phenolics, peptides, organic acids, enzymes, and Maillard reaction products. Honey has also been used in some gastrointestinal, cardiovascular, inflammatory and neoplastic states. This review covers the composition, physico-chemical properties and the most important uses of natural honey in human diseases. PMID:23997898

Eteraf-Oskouei, Tahereh; Najafi, Moslem

2013-06-01

332

Coordinated Activation of Candidate Proto-Oncogenes and Cancer Testes Antigens via Promoter Demethylation in Head and Neck Cancer and Lung Cancer  

PubMed Central

Background Epigenetic alterations have been implicated in the pathogenesis of solid tumors, however, proto-oncogenes activated by promoter demethylation have been sporadically reported. We used an integrative method to analyze expression in primary head and neck squamous cell carcinoma (HNSCC) and pharmacologically demethylated cell lines to identify aberrantly demethylated and expressed candidate proto-oncogenes and cancer testes antigens in HNSCC. Methodology/Principal Findings We noted coordinated promoter demethylation and simultaneous transcriptional upregulation of proto-oncogene candidates with promoter homology, and phylogenetic footprinting of these promoters demonstrated potential recognition sites for the transcription factor BORIS. Aberrant BORIS expression correlated with upregulation of candidate proto-oncogenes in multiple human malignancies including primary non-small cell lung cancers and HNSCC, induced coordinated proto-oncogene specific promoter demethylation and expression in non-tumorigenic cells, and transformed NIH3T3 cells. Conclusions/Significance Coordinated, epigenetic unmasking of multiple genes with growth promoting activity occurs in aerodigestive cancers, and BORIS is implicated in the coordinated promoter demethylation and reactivation of epigenetically silenced genes in human cancers.

Smith, Ian M.; Glazer, Chad A.; Mithani, Suhail K.; Ochs, Michael F.; Sun, Wenyue; Bhan, Sheetal; Vostrov, Alexander; Abdullaev, Ziedulla; Lobanenkov, Victor; Gray, Andrew; Liu, Chunyan; Chang, Steven S.; Ostrow, Kimberly L.; Westra, William H.; Begum, Shahnaz; Dhara, Mousumi; Califano, Joseph

2009-01-01

333

Experience with the resection of parapharyngeal cancers via the infratemporal fossa approach.  

PubMed

Between 1982 and 1984, a modified infratemporal fossa approach was used to resect cancers with extensive primary or secondary involvement of the infratemporal fossa and parapharynx in 10 patients. Nine patients exhibited persistent or recurrent disease of the upper aerodigestive tract and posterior cranial fossa following planned, curative-intent therapy; the remaining patient had a carcinoma ex-pleomorphic adenoma of the deep lobe of the parotid gland with a significant infratemporal fossa extension. Considered to have "unresectable" tumors, by traditional methods, 7 of the 10 patients underwent an en-bloc resection of their lesions with tumor-free margins. Tumor was present at the margins of the specimens in the other 3 patients. Two of the 10 patients died early in the postoperative period of medical complications. Another died 5 months postoperatively of a tumor-induced internal carotid artery rupture at the level of the foramen lacerum. A fourth patient died of his disease 6 months following his resection. One patient is alive, but has metastatic meningioma 2 years after surgery. The 5 remaining patients are without evidence of disease, with a mean follow up of 2 years. Indications for and refinements of the operative technique, particularly those related to the repair of such extensive ablative defects, are outlined on the basis of this early experience. PMID:3083356

Smith, P G; Sharkey, D E

1986-03-01

334

Radiotherapy Alone With Curative Intent in Patients With Stage I Extranodal Nasal-Type NK/T-Cell Lymphoma  

SciTech Connect

Purpose: This study aims to evaluate the outcome and pattern of failure in a large cohort of patients with Stage I NK/T-cell lymphoma of the upper aerodigestive tract treated with radiotherapy alone. Methods and Materials: The pathological diagnosis was confirmed using standard criteria. All patients were treated with high-dose extended-field radiotherapy alone. The median dose was 50 Gy. The primary tumor was located in the nasal cavity (n = 80), Waldeyer ring (n = 5), or oral cavity (n = 2). Results: The overall response to radiotherapy was achieved in 85 of 87 (97.7%) patients, with a complete response rate of 95.4% and a partial response rate of 2.3%. The 5-year overall survival, progression-free survival, and local control rates for all patients were 80%, 69%, and 93%, respectively. Twenty patients (23%) had disease progression or relapse. Of these, 15 patients (17%) developed systemic extranodal disseminations, whereas only 4 (5%) patients had local relapse and 4 (5%) patients had lymph node relapse. Conclusions: Our study suggests that high-dose extended-field radiotherapy alone is a curative therapy and shows favorable clinical outcome in patients with Stage I disease. With the high possibility of local control and primary failure of systemic dissemination, the integration of optimal radiotherapy with more effective systematic therapy is warranted to bring additional improvement to the outcome for these patients.

Li Yexiong, E-mail: yexiong@yahoo.com [Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC), Beijing (China); Wang Hua; Jin Jing; Wang Weihu; Liu Qingfeng; Song Yongwen; Wang Zhaoyang; Qi Shunan; Wang Shulian; Liu Yueping; Liu Xinfan; Yu Zihao [Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC), Beijing (China)

2012-04-01

335

Risk of hepatocellular carcinoma and cancers at other sites among patients diagnosed with chronic hepatitis B virus infection in Sweden.  

PubMed

Hepatitis B virus (HBV) infection is one of most common viral infections worldwide. While chronic HBV infection has been shown consistently to be associated with hepatocellular carcinoma, data on associations with cancers at other sites are limited. In this study a total of 10,197 patients were diagnosed with chronic HBV infection in Sweden, and they were retrieved from the nationwide Swedish Hospital Discharge Register and Outpatient Register and linked to Cancer Registry data. Standardized incidence ratios (SIRs) for cancers were calculated for these patients in comparison with the population without HBV infection. Five hundred sixty-seven of whom developed cancer (SIR 1.82 (95% confidence interval (CI) 1.67-1.97)) during the study period. The SIR for hepatocellular carcinoma in patients with HBV infection was 40.58 (95% CI 30.50-50.07). In addition, a total of seven other cancer sites/types showed increased SIRs: cancers of the upper aerodigestive tract, lung, kidney, skin (squamous cell carcinoma), and thyroid gland, and lymphoma and leukemia. The risks of non-Hodgkin lymphoma and acute myeloid leukemia were increased in both Swedish- and foreign-born patients with HBV infection. In summary, chronic HBV infection is a strong risk factor for hepatocellular carcinoma and also increases the risk of seven other cancers. These findings illustrate the need for surveillance for cancers other than hepatocellular carcinoma in patients with HBV infection. PMID:24038002

Sundquist, Kristina; Sundquist, Jan; Ji, Jianguang

2014-01-01

336

Successful imatinib therapy of neuroendocrine carcinoma with activating KIT mutation: a case study  

PubMed Central

Neuroendocrine (NET) and gastro-intestinal stromal tumors (GIST) are believed to originate from the cells of Cajal [1-3] that are randomly dispersed along the aero-digestive tract. Despite distinct morphological appearance, NET and GIST may share oncogenic mechanisms. Presenting often in the metastatic setting, treatment options for patients with NET are limited. We are reporting a case of a patient with refractory metastatic NET who did not respond conventional chemotherapy. The patient was treated with a KIF11 inhibitor in a Phase I clinical trial and had a prolonged and clinically meaningful partial response. Upon progression at 20 months, the patient’s tumor was sequenced to reveal a KIT exon 11 mutation. Institution of imatinib therapy achieved a rapid and sustained anti-tumor effect with profound clinical benefit. Despite previously reported KIT expression in NET, this is the first documented case of an activating KIT mutation in NET and of successful treatment with both a KIF11 inhibitor and imatinib, each of which was elucidated through molecular profiling of the patient's tumor. Imatinib may be a valuable therapy in NET harboring activating KIT mutations.

Perkins, James; Boland, Patrick; Cohen, Steven J.; Olszanski, Anthony; Zhou, Yan; Engstrom, Paul; Astsaturov, Igor

2014-01-01

337

Assessment of Margins in Transoral Laser and Robotic Surgery  

PubMed Central

The growing practice of endoscopic surgery has changed the therapeutic management of selected head and neck cancers. Although a negative surgical margin in resection of neoplasm is the most important surgical principle in oncologic surgery, controversies exist regarding assessment and interpretation of the status of margin resection. The aim of this review was to summarize the literature considering the assessment and feasibility of negative margins in transoral laser microsurgery (TLM) and transoral robotic surgery (TORS). Free margin status is being approached differently in vocal cord cancer (1–2 mm) compared with other sites in the upper aerodigestive tract (2–5 mm). Exposure, orientation of the pathological specimen, and co-operation with the pathologist are crucial principles needed to be followed in transoral surgery. Piecemeal resection to better expose deep tumor involvement and biopsies taken from surgical margins surrounding site of resection can improve margin assessment. High rates of negative surgical margins can be achieved with TLM and TORS. Adjuvant treatment decision should take into consideration also the surgeon’s judgment with regard to the completeness of tumor resection.

Hamzany, Yaniv; Brasnu, Daniel; Shpitzer, Thomas; Shvero, Jacob

2014-01-01

338

Locally advanced thyroid cancer: therapeutic options.  

PubMed

The authors report on their experience in the management of thyroid cancer, with specific regard to advanced disease. Thyroid carcinomas behave differently according to: pathology, sex, age, grading and size. Differentiated lesions have a favourable outlook, while for less-differentiated tumours the prognosis is dismal. Extent of resection, lymphectomy technique and management of advanced disease remain matters of debate. Of particular interest are those neoplasms invading the upper aerodigestive tract, characterised by a worse prognosis in the case of differentiated tumours (1-6%), indicating an exceedingly aggressive behaviour in what is usually a slowly evolving disease. Surgery, with a curative intent or for palliation, is mandatory. The tumour progressively invades the tracheal lumen and is seldom manageable by alternative, non-surgical methods, and in any case only for short periods of time. Total thyroidectomy with tracheal resection and anastomosis is the surgical technique of choice and, when combined with radiometabolic therapy and/or external radiotherapy, yields survival data comparable with those relating to less advanced differentiated lesions. Tracheal stents and tracheotomy improve the quality of life. Laser therapy is indicated in cases of asphyxia, and as a preliminary step with a view to subsequent radical or palliative treatments. PMID:15452988

Avenia, Nicola; Ragusa, Mark; Monacelli, Massimo; Calzolari, Filippo; Daddi, Niccolò; Di Carlo, Luciana; Semeraro, Antonia; Puma, Francesco

2004-01-01

339

Aggregatibacter actinomycetemcomitans leukotoxin cytotoxicity occurs through bilayer destabilization  

PubMed Central

Summary The Gram-negative bacterium, Aggregatibacter actinomycetemcomitans, is a common inhabitant of the human upper aerodigestive tract. The organism produces an RTX (Repeats in ToXin) toxin (LtxA) that kills human white blood cells. LtxA is believed to be a membrane-damaging toxin, but details of the cell surface interaction for this and several other RTX toxins have yet to be elucidated. Initial morphological studies suggested that LtxA was bending the target cell membrane. Because the ability of a membrane to bend is a function of its lipid composition, we assessed the proficiency of LtxA to release of a fluorescent dye from a panel of liposomes composed of various lipids. Liposomes composed of lipids that form nonlamellar phases were susceptible to LtxA-induced damage while liposomes composed of lipids that do not form non-bilayer structures were not. Differential scanning calorimetry demonstrated that the toxin decreased the temperature at which the lipid transitions from a bilayer to a nonlamellar phase, while 31P nuclear magnetic resonance studies showed that the LtxA-induced transition from a bilayer to an inverted hexagonal phase occurs through the formation of an isotropic intermediate phase. These results indicate that LtxA cytotoxicity occurs through a process of membrane destabilization.

Brown, Angela C.; Boesze-Battaglia, Kathleen; Du, Yurong; Stefano, Frank P.; Kieba, Irene R.; Epand, Raquel F.; Kakalis, Lazaros; Yeagle, Philip L.; Epand, Richard M.; Lally, Edward T.

2012-01-01

340

Effect of a one-way tracheotomy speaking valve on the incidence of aspiration in previously aspirating patients with tracheotomy.  

PubMed

The purpose of the present study was to investigate the incidence of aspiration in previously aspirating patients with tracheotomy after use of a one-way tracheotomy tube speaking valve. Twenty consecutive inpatients from the acute care setting of a large urban tertiary care teaching hospital were included. All subjects had objective documentation of aspiration by a fiberoptic endoscopic evaluation of swallowing prior to placement of a one-way tracheotomy speaking valve, from 2 to 7 days of valve use with intelligible speech production, and no surgery to the upper aerodigestive tract except tracheotomy. Results indicated that incidence of aspiration was not affected by use of a one-way tracheotomy speaking valve. These results are in agreement with previous observations that subjects either aspirated or swallowed successfully regardless of tracheotomy tube occlusion status. Also, no significant differences were found between aspiration status and time since tracheotomy, time off ventilator, or duration of valve use. It was concluded that use of a one-way speaking valve provided mostly nondeglutitive benefits and should not be considered to promote successful swallowing for patients with tracheotomy in the acute care setting. PMID:10028036

Leder, S B

1999-01-01

341

Lipoma of the larynx: a case report  

PubMed Central

Summary Lipoma is a benign tumour of mesenchymal origin with a very rare occurrence in the upper aero-digestive tract. To date, approximately 100 cases have been described in the literature. This lesion has a slow growth and, therefore, can present with various symptoms due to the mass effect with obstruction and compression on neighbouring structures, including dysphagia for liquid and solid food, dyspnoea and hoarseness. For a precise pre-operative diagnosis, indirect or direct laryngoscopy (flexible fibre-optic laryngoscopy) can be employed or, if necessary, also imaging techniques such as computed tomography scan and magnetic resonance imaging scan. These offer more useful information for better treatment planning. Surgery is the treatment of choice and includes endoscopic techniques and an external surgical approach (cervicotomy). It is very important to completely remove these benign neoplasms in order to avoid local recurrence. The present report refering to a case of laryngeal lipoma removed through an external surgical approach, aims to demonstrate that the choice of an external surgical approach is required for complete surgical removal of a large lipoma in order to prevent any possible recurrence. Furthermore, it is useful to keep in mind the possibility of recurrence of lipomas after long free intervals; therefore, it is mandatory to observe these patients at long-term follow-up.

De Vincentiis, M; Greco, A; Mascelli, A; Soldo, P; Zambetti, G

2010-01-01

342

Molecular predictors of clinical outcome in patients with head and neck squamous cell carcinoma  

PubMed Central

Head and neck squamous cell carcinoma (HNSCC) involves the upper aerodigestive tract and can destroy the structure and function of organs involved in voice, speech, taste, smell and hearing, as well as vital structures necessary for survival. HNSCC has long been a treatment challenge because of the high rate of recurrences and of advanced disease at the time of diagnosis. Molecular identification of tissue biomarkers in diagnostic biopsy specimens may not only identify patients at risk for developing HNSCC but may also select patients that may benefit from more aggressive treatment modalities. Several biomarkers studied to date such as the proteins p53, cyclin D1, p16, Cox-2 enzyme, epidermal growth factor and vascular endothelial growth factor receptors, matrix metalloproteinases and the Fhit marker for genomic instability could be manipulated for the therapeutic benefit of these patients. This review presents the most updated information on molecular biomarkers with the greatest prognostic potential in HNSCC and discusses some factors that contribute to the controversy concerning their prognostic importance.

Thomas, Giovana R; Nadiminti, Hari; Regalado, Jacinto

2005-01-01

343

Aspartame, low-calorie sweeteners and disease: regulatory safety and epidemiological issues.  

PubMed

Aspartame is a synthetic sweetener that has been used safely in food for more than 30 years. Its safety has been evaluated by various regulatory agencies in accordance with procedures internationally recognized, and decisions have been revised and updated regularly. The present review summarizes the most relevant conclusions of epidemiological studies concerning the use of low-calorie sweeteners (mainly aspartame), published between January 1990 and November 2012. In the Nurses' Health study and the Health Professionals Followup study some excess risk of Hodgkin lymphoma and multiple myeloma was found in men but not in women; no association was found with leukemia. In the NIH-AARP Diet and Health Study, there was no association between aspartame and haematopoietic neoplasms. US case-control studies of brain and haematopoietic neoplasms also showed no association. The NIH-AARP Diet and Health Study and case-control studies from California showed no association with pancreatic cancer, and a case-control study from Denmark found no relation with breast cancer risk. Italian case-control studies conducted in 1991-2008 reported no consistent association for cancers of the upper aerodigestive tract, digestive tract, breast, endometrium, ovary, prostate, and kidney. Low calorie sweeteners were not consistently related to vascular events and preterm deliveries. PMID:23891579

Marinovich, Marina; Galli, Corrado L; Bosetti, Cristina; Gallus, Silvano; La Vecchia, Carlo

2013-10-01

344

Alcohol as a cause of cancer.  

PubMed Central

This is a review of the epidemiologic literature on alcohol and risks of various cancers. Alcohol has consistently been related to risks of squamous cell carcinomas of the mouth, oral pharynx, larynx, and esophagus in multiple studies of varying design. The joint effects of alcohol and smoking are greater than additive, and are probably multiplicative, suggesting biological synergism. All major types of alcoholic beverages have been casually implicated in the genesis of these diseases. The influence of alcohol on risks of upper aerodigestive tract cancers may be greater in persons with marginal nutritional status than in better-nourished individuals. Alcohol also has been associated with an increased risk of adenocarcinomas of the esophagus, gastro-esophageal junction, and gastric cardia, but the relationship is not as strong as for squamous cell esophageal carcinomas. Alcohol and tobacco account for over 80% of the squamous carcinomas of the mouth, pharynx, larynx, and esophagus in the United States. Risks of cancers of the distal stomach, pancreas, colon, and rectum have not been consistently related to alcohol, although possible relationships between beer drinking and rectal cancer and between heavy use of alcohol and pancreatic cancer warrant further study. Studies of alcohol and liver cancer, in which the confounding influence of hepatitis B was considered, have yielded inconsistent results and should be replicated. An association between heavy alcohol use and breast cancer has been observed in most studies, even after controlling for known risk factors for breast cancer, and additional investigations of this issue are warranted.

Thomas, D B

1995-01-01

345

Long-term survival after liver transplantation for alcoholic liver disease  

PubMed Central

Currently, alcoholic cirrhosis is the second leading indication for liver transplantation in the United States and Europe. The quality of life and survival after a liver transplantation (LT) in patients with alcoholic liver disease (ALD) are similar to those in patients with other cirrhosis etiologies. The alcoholic relapse rate after a LT varies from 10%-50%, and these relapse patients are the ones who present a reduced long-term survival, mainly due to cardiovascular diseases and the onset of de novo neoplasms, including lung and upper aerodigestive tract. Nearly 40% of ALD recipients resume smoking and resume it early post-LT. Therefore, our pre-and post-LT follow-up efforts regarding ALD should be focused not only on alcoholic relapse but also on treating and avoiding other modifiable risk factors such as tobacco. The psychiatric and psychosocial pre-LT evaluation and the post-LT follow-up with physicians, psychiatrists and addiction specialists are important for reversing these problems because these professionals help to identify patients at risk for relapse as well as those patients who have relapsed, thus enabling responsive actions.

Iruzubieta, Paula; Crespo, Javier; Fabrega, Emilio

2013-01-01

346

Cancer of the head and neck.  

PubMed Central

Cancers of the upper aerodigestive tract, collectively known as head and neck cancers, arise from a multiplicity of sites. In the West, excess tobacco and alcohol consumption are the most important of the known predisposing factors; elsewhere in the world, notably in India and China, the aetiology, pattern of primary sites, and clinical behaviour are different. Clinically these tumours pose exceptional problems in management, and skilled multidisciplinary teams are necessary in order to achieve the highest level of service and research. Historically, surgery and radiotherapy have been the most important treatment modalities; chemotherapy is now increasingly employed but not yet fully established. Successful rehabilitation of patients with head and neck cancers requires access to high quality speech therapists and other support staff with training in functional pharyngeal disorders. Current research efforts are largely directed towards defining the proper role of chemotherapy and assessing the possible advantage of unconventional radiation approaches. In recent years the roles of primary, reconstructive, and salvage surgery have also become better defined. Many patients are suitable for randomisation into ongoing prospective clinical trials which have been specifically designed to address these issues. Images FIG 3 FIG 4 FIG 5

Tobias, J. S.

1994-01-01

347

Laryngeal dysplasia and the human papillomavirus.  

PubMed

The relationship between the human papillomavirus (HPV) and cancer of the upper aerodigestive trace is controversial. There is no doubt that at least some nasal, oral, pharyngeal and laryngeal carcinomas contain HPV DNA. However, the diversity in the reported incidence of HPV in these tumours represents a major problem. In the present study we have examined 30 laryngeal dysplastic lesions for HPV by the polymerase chain reaction, using three different pairs of consensus primers (GP5+/GP6+, MY09/MY11 and CPI/CPII). The single HPV-positive specimen was from a recurrent laryngeal papilloma. The HPV type present could not be determined, but it was not type 6, 11, 16, 18, 30, 31, 33 or 45. Restriction fragment length polymorphy analysis suggested a yet unknown HPV-type in this lesion. This investigation does not support the idea of HPV as an oncogenic cofactor in most laryngeal carcinomas as HPV was present in only 1/30 precancerous laryngeal lesions. PMID:9298618

Lindeberg, H; Krogdahl, A

1997-08-01

348

New insights into the dual recruitment of IgA+ B cells in the developing mammary gland.  

PubMed

In monogastric mammals, transfer of passive immunity via milk and colostrum plays an important role in protecting the neonate against mucosal infections. Here we analyzed the hypothesis that during gestation/lactation IgA+ plasmablasts leave the intestinal and respiratory surfaces towards the mammary gland (MG). We compared the recruitment of lymphocytes expressing homing receptors alpha4beta1 and alpha4beta7 to expression of their vascular counter-receptors, VCAM-1 and MAdCAM-1. Furthermore, the expression of the chemokines responsible for the recruitment of IgA+ plasmablasts was analyzed. Data confirmed that expressions of CCL28 and MAdCAM-1 in the MG increased during pregnancy and alpha4beta1+ and alpha4beta7+/IgA+ cell recruitment in lactation correlated with increase of CCL28 expression. Interestingly, VCAM-1 expression was found in small blood vessels of the lactating porcine MG, while in mice VCAM-1 was expressed in large blood vessels within the MG. Thus, our results indicate that the recruitment of IgA+ plasmablasts to MG is mediated by VCAM-1/alpha4beta1 and MAdCAM-1/alpha4beta7 in conjunction with CCL28/CCR10. They support the existence of a functional link between entero- and upper respiratory surfaces and MG, thereby, conferring protection against aero-digestive pathogens in the newborn. PMID:18533264

Bourges, Dorothée; Meurens, François; Berri, Mustapha; Chevaleyre, Claire; Zanello, Galliano; Levast, Benoît; Melo, Sandrine; Gerdts, Volker; Salmon, Henri

2008-07-01

349

A Case-Control Study of the Role of Human Papillomavirus in Oesophageal Squamous Cell Carcinoma in Australia  

PubMed Central

Objective. We investigate the prevalence of human papillomavirus (HPV) in oesophageal squamous cell carcinoma (OSCC) tissues compared to oesophageal tissue from healthy controls, in an Australian cohort. Methods. We conducted a hospital-based case-control study of 99 patients with OSCC and 100 healthy controls to examine the presence of HPV DNA. Paraffin tissues were tested using the PapType high-risk HPV detection and genotyping kit and with INNO-LiPA HPV Genotyping Extra. The biopsy samples were tested for HPV using a PCR-ELISA method based on the L1 consensus primer set PGMY09-PGMY11. Results. HPV DNA of the oncogenic genotype 16 was detected in 1/99 case specimens, a rate of 1010 per 100,000 (95% CI: 30–5500). All control specimens were negative for HPV. Significantly higher rates of smoking, other aerodigestive cancers, and mortality were seen among cases than controls. A pooled analysis of this study and the only other Australian case-control study found that 9/321 cases and 0/155 controls were positive for HPV. The pooled odds ratio for HPV being a risk factor for OSCC was 9.35 (95% CI: 0.47–190.33). Conclusion. Our results suggest that in this multifactorial cancer HPV may be an additional risk factor; although a larger, better powered study is needed.

Liyanage, Surabhi S.; Malik, Aisha; Garland, Suzanne M.; Tabrizi, Sepehr N.; Rahman, Bayzidur; Barbour, Andrew P.; Crowe, Philip J.; MacIntyre, C. Raina

2014-01-01

350

Optical coherence tomography and confocal endomicroscopy for rhinologic pathologies: a pilot study  

NASA Astrophysics Data System (ADS)

Optical coherence tomography (OCT) and confocal endomicroscopy (CEM) have a well-established potential for early diagnosis of pre-malignant and early malignant lesions of the upper aerodigestive tract mucosa. Additional applications in ENT-diagnostics might facilitate a more widespread use by making the investment into the devices more economic. Both imaging techniques might also provide valuable information in nasal pathologies. OCT images were generated with a surgical microscope (Möller-Wedel Hi-R 1000) with an integrated high-speed-OCT camera (Optomedical GmbH). For the CEM a Heidelberg Retina tomograph II scanner (Heidelberg Engineering GmbH) was used. Both during sinus surgery in vivo and from removed material ex vivo OCT and CEM images were taken and correlated with histopathological analysis after hematoxylin and eosin staining. Patients with inverted papillomas and chronic rhinosinusitis (CRS) were evaluated. Inverted papillomas show a variably thick epithelial layer on OCT and densely packed epithelial cells on CEM. They can be clearly distinguished from nasal polyps that show a very thin epithelial layer upon loose subepithelial tissue. In CRS CEM can distinguish areas with intact from areas with destroyed ciliated epithelium by directly visualizing ciliary movement. OCT sometimes showed thin superficial dense structures that might correspond to biofilms. OCT and CEM might provide valuable information in the follow-up care of patients with inverted papillomas and in diagnostics of CRS.

Olzowy, B.; Starke, N.; Schuldt, T.; Hüttmann, G.; Lankenau, E.; Just, T.

2013-06-01

351

Imaging of penetrating injuries of the head and neck:current practice at a level I trauma center in the United States.  

PubMed

Penetrating neck injuries are commonly related to stab wounds and gunshot wounds in the United States. The injuries are classified by penetration site in terms of the three anatomical zones of the neck. Based on this zonal classification system, penetrating injuries to the head and neck have traditionally been evaluated by conventional angiography and/or surgical exploration. In recent years, multidetector-row computed tomography (CT) angiography has significantly improved detectability of vascular injuries and extravascular injuries in the setting of penetrating injuries. CT angiography is a fast and minimally invasive imaging modality to evaluate penetrating injuries of the head and neck for stable patients. The spectrum of penetrating neck injuries includes vascular injury (extravasation, pseudoaneurysm, dissection, occlusion, and arteriovenous fistula), aerodigestive injury (esophageal and tracheal injuries), salivary gland injury, neurologic injury (spinal canal and cerebral injuries), and osseous injury, all of which can be evaluated using CT angiography. Familiarity with the complications and imaging characteristics of penetrating injuries of the head and neck is essential for accurate diagnosis and optimal treatment. PMID:24965876

Saito, Naoko; Hito, Rania; Burke, Peter A; Sakai, Osamu

2014-06-25

352

Traditional and Modern Uses of Natural Honey in Human Diseases: A Review  

PubMed Central

Honey is a by-product of flower nectar and the upper aero-digestive tract of the honey bee, which is concentrated through a dehydration process inside the bee hive. Honey has a very complex chemical composition that varies depending on the botanical source. It has been used both as food and medicine since ancient times. Human use of honey is traced to some 8000 years ago as depicted by Stone Age paintings. In addition to important role of natural honey in the traditional medicine, during the past few decades, it was subjected to laboratory and clinical investigations by several research groups and it has found a place in modern medicine. Honey has been reported to have an inhibitory effect on around 60 species of bacteria, some species of fungi and viruses. Antioxidant capacity of honey is important in many disease conditions and is due to a wide range of compounds including phenolics, peptides, organic acids, enzymes, and Maillard reaction products. Honey has also been used in some gastrointestinal, cardiovascular, inflammatory and neoplastic states. This review covers the composition, physico-chemical properties and the most important uses of natural honey in human diseases.

Eteraf-Oskouei, Tahereh; Najafi, Moslem

2013-01-01

353

Gene-Environment Interactions of Novel Variants Associated with Head and Neck Cancer  

PubMed Central

Background A genome-wide association study for upper aerodigestive tract cancers identified 19 candidate single-nucleotide polymorphisms (SNPs). We used these SNPs to investigate the potential gene-gene and gene-environment interactions in head and neck squamous cell carcinoma (HNSCC) risk. Methods The 19 variants were genotyped using Taqman (Applied Biosystems) assays among 575 cases and 676 controls in our population-based case-control study. Results A restricted cubic spline model suggested both ADH1B and HEL308 modified the association between smoking pack-years and HNSCC. Classification and regression tree analysis demonstrated a higher order interaction between smoking status, ADH1B, FLJ13089 and FLJ35784 in HNSCC risk. Compared with ever smokers carrying ADH1B T/C+T/T genotypes, smokers carrying ADH1B C/C genotype and FLJ13089 A/G+A/A genotypes had a highest risk of HNSCC (OR=1.84). Conclusions Our results suggest that the risk associated with these variants may be specifically important amongst specific exposure groups.

Liang, Caihua; Marsit, Carmen J.; Houseman, E. Andres; Butler, Rondi; Nelson, Heather H.; McClean, Michael D.; Kelsey, Karl T.

2013-01-01

354

Otolaryngologic manifestations of diffuse idiopathic skeletal hyperostosis.  

PubMed

Diffuse idiopathic skeletal hyperostosis (DISH) is characterized by formation of large cervical osteophytes that may compress the posterior wall of the aerodigestive tract. It is a rare cause of dysphagia in the elderly. The aim of this study was to investigate the various otolaryngologic manifestations of DISH. Eleven elderly patients with DISH were included in the study. All patients presented with dysphagia that was graded on the swallowing screening tool (EAT-10), and the diagnosis of DISH was based on computed tomographic criteria. The patients were subjected to otolaryngologic examination and flexible laryngoscopy. Polysomnography was used for patients with excessive daytime sleepiness for detection of obstructive sleep apnea (OSA). In addition to dysphagia of varying severity, OSA was found in nine patients, change of voice in six, globus sensation in seven, aspiration in three, and cervical pain in seven. Flexible laryngoscopy showed bulging of the posterior pharyngeal wall in all patients. DISH may be an unrecognized contributory factor to both dysphagia and OSA in the elderly. Change of voice, aspiration, globus sensation, and cervical pain are other otolaryngologic manifestations that may be encountered symptoms of the disease. An otolaryngologist should be aware of the disease that may be overlooked, and computed tomography is a confirmatory diagnostic method. PMID:24264765

Abdel-Aziz, Mosaad; Azab, Noha A; Rashed, Mohammed; Talaat, Ahmed

2014-06-01

355

[Recent advances in the treatment of laryngeal and hypopharyngeal carcinoma].  

PubMed

The prognosis of squamous epithelial cell carcinoma of the upper aerodigestive tract has improved considerably in the last 30 years. Patients presenting with stage I or II disease are treated with surgery or radiation therapy with curative intent. Although the efficacy is comparable between the two methods, surgery is usually preferred so that the side effects and late toxic effects of radiation can be avoided. For the treatment of advanced stages of disease, surgery, radiotherapy, chemotherapy and immunotherapy are usually combined. The introduction of concurrent administration of chemotherapy and radiotherapy (chemoradiotherapy) has been a major advancement. This has resulted in local control and survival rates comparable to those seen following radical surgery and postoperative radiotherapy, but with preservation of the larynx in most patients. However, recent epidemiological observations have shown declining survival rates in laryngeal cancer patients, raising concern about uncritical and too frequent use of this approach. The rationale for choosing treatment options for patients with laryngeal and hypopharyngeal carcinoma is discussed. PMID:22282006

Eckel, H E

2012-01-01

356

Successful Imatinib Therapy for Neuroendocrine Carcinoma With Activating KIT Mutation: A Case Study.  

PubMed

Neuroendocrine tumors (NET) and gastrointestinal stromal tumors (GIST) are believed to originate from the cells of Cajal that are randomly dispersed along the aerodigestive tract. Despite their distinct morphologic appearance, NET and GIST may share oncogenic mechanisms. Often presenting in the metastatic setting, treatment options for patients with NET are limited. This case report presents a patient with refractory metastatic NET that did not respond conventional chemotherapy. The patient was treated with a KIF11 inhibitor in a phase I clinical trial and experienced a prolonged and clinically meaningful partial response. On progression at 20 months, the patient's tumor was sequenced to reveal a KIT exon 11 mutation. Institution of imatinib therapy achieved a rapid and sustained antitumor effect with profound clinical benefit. Despite previously reported KIT expression in NET, this is the first documented case of an activating KIT mutation in NET and of successful treatment with both a KIF11 inhibitor and imatinib, each of which was elucidated through molecular profiling of the patient's tumor. Imatinib may be a valuable therapy in NET harboring activating KIT mutations. PMID:24925195

Perkins, James; Boland, Patrick; Cohen, Steven J; Olszanski, Anthony J; Zhou, Yan; Engstrom, Paul; Astsaturov, Igor

2014-06-01

357

Laser resistance and clinical application of a new endotracheal tube  

NASA Astrophysics Data System (ADS)

The protection of endotracheal tubes against laser induced ignition is necessary to enable a safe laser surgery of the upper aerodigestive tract. It was found, that tubes of polymers, like PVC, have a low ignition threshold and even worse evaporate toxic gases when accidentally irradiated by the laser beam. So far, a pure metal tube was described as the safest endotracheal tube. A new compound endotracheal tube build up by a rubber tube surrounded by an ondulated silver foil and a layer of white MerocelTM-foam, was tested to it's laser stability against the CO2-laser. The damage threshold of this tube was 3 X 106 W/cm2 and is significantly higher than the damage threshold of the metal tube and far above the power density used for coagulation or ablation of tissue. Beside these experimental results, the contribution contains experiences and preliminary results obtained from a randomized clinical study, in which the new compound tube so far has proven to be ideal in handling and till now has not caused any problems concerning the laser resistance.

Baker-Schreyer, Antonio; Bergler, Wolfgang; Foth, Hans-Jochen; Hoermann, Karl; Ungemach, Josef

1995-05-01

358

Diagnostic Biopsy of Lymph Nodes of the Neck, Axilla and Groin: Rhyme, Reason or Chance?  

PubMed Central

INTRODUCTION Improving patient pathways of care is becoming increasingly important in the delivery of timely, appropriate surgical care. With this aim, we analysed the referral and management pathway of patients undergoing diagnostic superficial lymph node biopsy. PATIENTS AND METHODS A retrospective review of case notes of patients undergoing diagnostic superficial lymph node biopsy over 3 years, 1998–2000 at the Bradford Hospitals NHS Trust. Indication for surgical biopsy was based on clinical suspicion following assessment in the out-patient clinic for the majority, and arrangement of investigations as deemed appropriate. There were no clinical algorithms in use during the study period. RESULTS There was no evidence for the use of explicit protocols for referral or management. Biopsy was often delayed. Of 268 patients referred from primary care, referral was made to any of 14 hospital departments with 39% (105 of 268) attending more than one outpatient appointment, and 155 (41 of 268) attending more than one department. Eighteen percent (47 of 268) of patients were informed of their diagnosis within 6 weeks of referral and 42% (113 of 268) within 3 months of referral. Nine percent (24 of 268) underwent pre-operative fine needle aspiration cytology. Of patients with enlarged neck nodes, 29% (52/180) had examination of the upper aero-digestive tract. CONCLUSIONS The study supports the introduction of co-ordinated problem-based referral and management pathways for the management of patients with enlarged superficial lymph nodes supported by regular audits of practice.

Moor, James W; Murray, Patrick; Inwood, Jane; Gouldesbrough, David; Bem, Chris

2008-01-01

359

[Neurological diseases and SPECT--analysis using easy Z-score imaging system (eZIS)].  

PubMed

We developed a method for automated diagnosis of brain perfusion SPECT and designated this method as an easy Z-score imaging system (eZIS). In this software program, voxel-by-voxel Z-score analysis after voxel normalization to global mean or cerebellar values; Z-score = ( [control mean] - [individual value] )/ (control SD) is performed. These Z-score maps are displayed by overlay on tomographic sections and by projection with averaged Z-score of 14mm thickness to surface rendering of the anatomically standardized MRI template. Anatomical standardization of SPECT images into a stereotactic space is performed using statistical parametric mapping (SPM) 2. This program has an advantage of capability of incorporation of SPM results into automated analysis of Z-score values as a volume of interest (VOI). A specific VOI can be determined by group comparison of SPECT images for patients with a neuropsychiatric disease with those for healthy volunteers using SPM. Even if a center can construct a normal database with good quality comprising a large number of healthy volunteers, other centers have not been able to use this normal database because of differences between the used gamma cameras, collimators and physical correction algorithms. Since SPECT exhibits greater variations in image quality among different centers than PET, conversion of SPECT images may be necessary for sharing a normal database. In this eZIS software, we incorporated a newly developed program for making it possible to share a normal database in SPECT studies. A Hoffman 3-dimensional brain phantom experiment was conducted to determine systematic differences between SPECT scanners. SPECT images for the brain phantom were obtained using two different scanners. Dividing these two phantom images after anatomical standardization by SPM created a 3-dimensional conversion map. The use of a conversion map obtained from SPECT images of the same phantom provided very similar SPECT data despite extreme differences between scanners. The present method may be useful for combining normal databases from different centers and greatly enhance the diagnostic value of brain SPECT imaging by standardization of data analysis using a common normal database. PMID:17533974

Matsuda, Hiroshi

2007-05-01

360

Functional imaging of neoadjuvant chemotherapy response in women with locally advanced breast cancer using diffuse optical spectroscopy.  

PubMed

Functional imaging with tomographic near infrared diffuse optical spectroscopy (DOS) can quantitatively measure tissue parameters such as the concentration of deoxy-hemoglobin (Hb), oxy-hemoglobin (HbO2), percent water (%water), and scattering power (SP). The purpose of this study was to evaluate the correlation between DOS functional parameters with pathologic outcomes. Patients with locally advanced breast cancer undergoing neoadjuvant chemotherapy or chemoradiotherapy were recruited to this study (n = 10). Five scans were conducted per patient: a baseline scan was taken up to 3 days prior to treatment and at 1 week, 4 weeks, 8 weeks, and after neoadjuvant treatment prior to surgery. At each scan the patient lay prone with the breast suspended between immobilization plates in optical coupling medium. Pulsed near-infrared laser light was used to scan the breast at four different wavelengths and data was used for tomographic reconstruction. Volume-of-interest (VOI) weighted tissue Hb, HbO2, %water, and SP corresponding to the tumour was calculated and compared to clinical and pathological response as determined from full mount mastectomy pathology. For all 10 patients the tumour-based VOI was significantly different than background tissue for all functional parameters (p<0.001). Five patients had a good clinical and pathologic response. Four patients were considered non-responders. One patient initially had a poor clinical response to chemotherapy but after a change in chemotherapy had a good clinical and radiographic response. Responders and non-responders were significantly different for all of the functional parameters (p<0.05) at the 4-week scan. In the 5 patients with a good response the mean drop in Hb, HbO2, %water, and SP from baseline to the 4-week scan was 70.4% (SD = 18.6), 66.5% (SD = 24.5), 59.6% (SD = 30.9), and 60.7% (SD = 29.2), respectively. In contrast, the 4 non-responders had a mean drop of 17.7% (SD = 9.8), 18.0% (SD = 20.8), 15.4% (SD = 11.7), and 12.6% (SD = 10.2), for Hb, HbO2, %water and SP, respectively. Functional imaging using tomographic diffuse optical spectroscopy parameters of Hb, HbO2, %water and SP could be used as an early detector of final clinical and pathologic tumor response. This could be evaluated in the future to assess responses and potentially adjust chemotherapy regimins. PMID:19964289

Soliman, Hany; Yaffe, Martin J; Czarnota, Gregory J

2009-01-01

361

Changes in Functional Integration with the Non-Epileptic Temporal Lobe of Patients with Unilateral Mesiotemporal Epilepsy  

PubMed Central

Purpose To investigate epilepsy-induced changes in effective connectivity between the non-epileptic amygdalo-hippocampal complex (AHC) and the rest of the brain in patients with unilateral mesiotemporal lobe epilepsy (MTLE) associated with hippocampal sclerosis (HS). Methods Thirty-three patients with unilateral MTLE associated with HS (20 females, mean age: 36 years, 19 left HS) and 33 adult controls matched for age and gender underwent 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET). Right-HS patients' FDG-PET data were flipped to obtain a left–epileptic–focus–lateralized group of patients. Voxels of interest (VOI) were selected within the cytoarchitectonic probabilistic maps of the non-epileptic AHC (probability level ?=?100%, SPM8 Anatomy toolbox v1.7). Patients and controls were compared using VOI metabolic activity as covariate of interest to search for epilepsy-induced changes in the contribution of the non-epileptic AHC to the level of metabolic activity in other brain areas. Age, gender, duration of epilepsy, seizure type and frequency were used as covariates of no-interest for connectivity analyses. Key findings Significant decrease in effective connectivity was found between the non-epileptic AHC and ventral prefrontal cortical areas bilaterally, as well as with the temporal pole and the posterior cingulate cortex contralateral to HS. Significant increase in connectivity was found between the non-epileptic AHC and midline structures, such as the anterior cingulate and dorsal medial prefrontal cortices, as well as the temporo-parietal junction bilaterally. Connectivity analyses also revealed a preserved positive connectivity between the non-epileptic and the epileptic AHC in the patients' group. Significance This study evidences epilepsy-induced changes in connectivity between the non-epileptic AHC and some limbic and default mode network areas. These changes in connectivity probably account for emotional, cognitive and decision-making impairments frequently observed in MTLE patients. The preserved neurometabolic connectivity between the non-epileptic and the epileptic AHC in MTLE patients is pivotal to explain the epilepsy-induced changes found in this study.

Trotta, Nicola; Goldman, Serge; Legros, Benjamin; Baete, Kristof; Van Laere, Koen; Van Bogaert, Patrick; De Tiege, Xavier

2013-01-01

362

The economic value of remote sensing information: a case study of agricultural production and groundwater vulnerability using applied environmental science and hydrogeospatial methods  

NASA Astrophysics Data System (ADS)

William M. Forney1*, Richard L. Bernknopf1, Shruti K. Mishra2, Ronald P. Raunikar1. 1=Western Geographic Science Center, US Geological Survey, Menlo Park, California. 2=Contractor, Western Geographic Science Center, US Geological Survey, Menlo Park, California *=Contact author, wforney@usgs.gov, 650-329-4237. Does remote sensing information provide economic benefits to society and can those benefits be valued? Can resource management and policy be better informed by coupling past and present earth observations with groundwater nitrate measurements? Using an integrated assessment approach, the USGS's research applies an established conceptual framework to answer these questions as well as estimate the value of information (VOI) for remote sensing imagery. The approach uses moderate resolution land imagery (MRLI) data from the Landsat and Advanced Wide Field Sensor satellites that has been classified by the National Agricultural Statistics Service into the Cropland Data Layer (CDL). Within the constraint of the US Environmental Protection Agency's public health threshold for potable groundwater resources, we model the relationship between a population of the CDL's land uses and the evolution of nitrate (NO3-) contamination of aquifers in a case study region in northeastern Iowa. Using source data from the Iowa Department of Natural Resources and the USGS's National Water Quality Assessment Program, the approach uses multi-scaled, environmental science models to address dynamic, biophysical process models of nitrogen fate and transport at specific sites (wells) and at landscape scale (35 counties) in order to assess groundwater vulnerability. In addition to the ecosystem service of potable groundwater, this effort focuses on particular agricultural goods and land uses: corn, soybeans and livestock manure management. Results of this four-year study will be presented, including: 1) the integrated models of the assessment approach, 2) mapping the range of vulnerabilities across the region, and 3) considerations of improved nitrogen and crop management. Finally, utilizing both a situation where society does not have access to MRLI, and an enhanced land use scenario based on plausible, future regulatory and policy frameworks and continued availability of MRLI, estimates of the incremental increase in the MRLI's VOI are presented.

Forney, W.; Bernknopf, R. L.; Mishra, S.; Raunikar, R. P.

2011-12-01

363

Effect of surrounding vasculature on intravoxel BOLD signal  

PubMed Central

Purpose: The nonlocal influence from distant magnetization will affect the magnetic field at a voxel in question. Existing reports on BOLD simulation only consider vasculature inside a single voxel, thus omitting the contribution from the surrounding regions. In this article, the authors study the effect of the surrounding vasculature on the magnetic field and the BOLD signal at a cortical voxel by numerical simulation. Methods: A cortical voxel is generated as a cubic bin filled with randomly networked capillary vessels. First, the authors generate a cortical voxel with a random vessel network and embed it in a greater voxel by filling its surrounding region with vasculatures by different strategies. Next, they calculate the blood-susceptibility-induced magnetic field (BOLD field) at the voxel of interest (VOI) by a Fourier transform technique for different surrounding scenarios and varying surrounding extent. The BOLD field inhomogeneity is described by a radial distribution with a collection of cubic shell masks. The surrounding extent is defined by a collection of concentric cubes, which encase the VOI. Given a BOLD field in the presence of surrounding vasculature, they calculate BOLD signals by intravoxel dephasing. Results: The influence from the surroundings on the BOLD field at a voxel in question mainly happens at the boundary. The most influence to the BOLD signal is from the inner surroundings. For a 160×160×160 ?m3 voxel embedded in a 480×480×480 ?m3 greater region, the surroundings could disturb the magnetic field by an amount in the range of [?0.002, 0.010] ppmT and could change the BOLD signal ratio in the range of [2.5%, 10%]. (These results were generated from the setting of ??bB0=3 ppmT, capillary={2.5,6,9} ?m, and relaxation time=60 ms). Conclusions: The surrounding vasculature will impose a magnetic field disturbance at the voxel in question due to the nonlocal influence of magnetization. Simulation results show that the surrounding vasculature significantly alters the magnetic field (up to 0.01 ppmT) and BOLD signal (typically no more than 10%) at the central voxel and thus should be considered in accurate BOLD modeling.

Chen, Zikuan; Caprihan, Arvind; Calhoun, Vince

2010-01-01

364

Pulmonary vessel segmentation utilizing curved planar reformation and optimal path finding (CROP) in computed tomographic pulmonary angiography (CTPA) for CAD applications  

NASA Astrophysics Data System (ADS)

Vessel segmentation is a fundamental step in an automated pulmonary embolism (PE) detection system. The purpose of this study is to improve the segmentation scheme for pulmonary vessels affected by PE and other lung diseases. We have developed a multiscale hierarchical vessel enhancement and segmentation (MHES) method for pulmonary vessel tree extraction based on the analysis of eigenvalues of Hessian matrices. However, it is difficult to segment the pulmonary vessels accurately under suboptimal conditions, such as vessels occluded by PEs, surrounded by lymphoid tissues or lung diseases, and crossing with other vessels. In this study, we developed a new vessel refinement method utilizing curved planar reformation (CPR) technique combined with optimal path finding method (MHES-CROP). The MHES segmented vessels straightened in the CPR volume was refined using adaptive gray level thresholding where the local threshold was obtained from least-square estimation of a spline curve fitted to the gray levels of the vessel along the straightened volume. An optimal path finding method based on Dijkstra's algorithm was finally used to trace the correct path for the vessel of interest. Two and eight CTPA scans were randomly selected as training and test data sets, respectively. Forty volumes of interest (VOIs) containing "representative" vessels were manually segmented by a radiologist experienced in CTPA interpretation and used as reference standard. The results show that, for the 32 test VOIs, the average percentage volume error relative to the reference standard was improved from 32.9+/-10.2% using the MHES method to 9.9+/-7.9% using the MHES-CROP method. The accuracy of vessel segmentation was improved significantly (p<0.05). The intraclass correlation coefficient (ICC) of the segmented vessel volume between the automated segmentation and the reference standard was improved from 0.919 to 0.988. Quantitative comparison of the MHES method and the MHES-CROP method with the reference standard was also evaluated by the Bland-Altman plot. This preliminary study indicates that the MHES-CROP method has the potential to improve PE detection.

Zhou, Chuan; Chan, Heang-Ping; Kuriakose, Jean W.; Chughtai, Aamer; Wei, Jun; Hadjiiski, Lubomir M.; Guo, Yanhui; Patel, Smita; Kazerooni, Ella A.

2012-02-01

365

Processus mis en jeu dans l'evolution morpho-dynamique de Roberts Bank (Delta du Fraser): Observation et modelisation hydrodynamiques et sedimentaires  

NASA Astrophysics Data System (ADS)

Roberts Bank couvre le delta intertidal entre le bras principal du fleuve Fraser et la pointe du Cap Roberts en Colombie Britannique, Canada. Sous la pression du developpement urbain et la modification du regime sedimentaire, cette plage de sable fin est soumise a une erosion significative. L'identification des forces hydrodynamiques, leur importance et leur interaction permettent de determiner les zones de transport, et donc la stabilite de Roberts Bank. Deux periodes de mesures associees a des phases de modelisation de la houle et des courants ont ete effectuees lors de ce travail. La premiere periode de mesure, entre le 29 juin et le 8 juillet 2001, a permis l'identification de processus hydrodynamiques et sedimentaires associes aux forts courants de maree presents le long de Roberts Bank. La seconde phase de mesure, entre le 1er mars et le 26 mars 2002, a permis d'etudier les processus de remise en suspension associes a la houle. Des phases de modelisation ont ete menees a partir des connaissances acquises sur le terrain, afin d'affiner la comprehension des processus sedimentaires et notamment les interactions houle - courant - sediment. Les mecanismes, mis en evidence dans cette etude, participent au faconnage de Roberts Bank, contribuent a son erosion et a la mise en place de nouvelles structures sedimentaires. Les courants de flot de maree vont initier la creation de nuages de resuspension de sediment depuis le fond. En eau peu profonde, la composante " onshore" du courant de maree induit un transport a la cote, tandis qu'en eau plus profonde une faible composante " offshore" du courant peut favoriser un transport au large le long de la pente. Les chenaux, les dunes subaquatiques et les surfaces d'erosion affleurantes fournissent une rugosite de fond suffisante a la generation de turbulence et donc de nuages de sediment en suspension. Lors de la maree de jusant, les sediments resuspendus en eau peu profonde, sont transportes vers le large a partir d'un panache de surface et par les chenaux deltaiques. Une forte turbulence favorisera un processus dit de "sedimentation convective induite par un melange turbulent" ("mixing-induced convective sedimentation "). Le comportement des vagues de tempete qui se propagent sur la partie superieure de la pente du Delta du Fraser depend du marnage, de l'incidence de propagation et de la morphologie sous-marine. Ces facteurs controlent une divergence dans le transport sedimentaire au niveau de la rupture de pente deltaique. A maree haute, le transport sedimentaire sera essentiellement "onshore".

Meule, Samuel

366

Interaction de Frohlich dans les structures de semiconducteurs a dimension reduite  

NASA Astrophysics Data System (ADS)

Dans les cristaux ioniques et les semi-conducteurs polaires, un electron supplementaire deforme le reseau avoisinant et se couple au champ de polarisation induit par ces deformations, c'est a dire avec les modes de phonons optiques du reseau. La quasi-particule ainsi formee est appelee polaron. L'interaction electron-phonons modifie les proprietes physiques (transport, diffusion electronique inelastique) des materiaux cristallins, et les proprietes optiques, lineaires et non-lineaires, des semi-conducteurs, selon la force du couplage. Notre objectif premier est l'analyse de l'effet d'un confinement anisotrope sur l'energie propre de l'etat fondamental et du premier etat excite du polaron, quand il existe dans la limite de confinement selon une direction, nous parlons de l'effet de la largeur du puits, du confinement dans deux et trois directions de l'effet du rayon du fil et du point quantiques respectivement. Il convient d'etudier de facon adequate les effets du potentiel de confinement, du couplage electron-phonons, du potentiel coulombien dans le cas du polaron lie, et du champ magnetique dans le cas du magnetopolaron. Nous appliquons la methode de Fock de Matz et Burkey, utilisee precedemment pour etudier les proprietes du polaron et du magnetopolaron de volume pour tout couplage polaire, a l'etude de l'effet de l'anisotropie du confinement sur l'etat fondamental et le premier etat excite du polaron. Cette approche utilise des hamiltoniens modeles et les spectres complets correspondants pour simuler de facon variationnelle la dynamique du polaron, dans toute la gamme de couplage electron-phonons. Avec un modele de l'impurete fixee au centre, nous estimons la correction polaronique maximale a l'energie de liaison du polaron lie. La correction polaronique a l'energie de liaison est une fonction decroissante de la taille du point. Le spectre d'energie du magnetopolaron dans le meme type de potentiel de confinement est beaucoup plus complexe. Nous obtenons une borne superieure pour les energies de l'etat fondamental et du premier etat excite pour tout couplage polaire et tout champ magnetique. De ce point de vue variationnel, nous retrouvons les theories anterieures comme cas limites. Dans l'etat fondamental, sous champ magnetique eleve, un polaron 3D prend un caractere 1D, tandis que le caractere 1D d'un polaron 1D est accru. Par contre, un champ magnetique faible n'entraine pas une modification de comportement dimensionnel. (Abstract shortened by UMI.)

Bruneau, Gwendoline

2001-07-01

367

Conception de lois de pilotage robustes et sequencement de gains par l'approche de systemes lineaires a parametres variants  

NASA Astrophysics Data System (ADS)

Cette recherche s'inscrit dans le cadre du projet de recherche Active Control Technology entre l'Ecole de Technologie Superieure et le constructeur Bombardier Aeronautique . Le but est de concevoir des strategies de commandes multivariables et robustes pour des modeles dynamiques d'avions. Ces strategies de commandes devraient assurer a l'avion une haute performance et satisfaire des qualites de vol desirees en l'occurrence, une bonne manoeuvrabilite, de bonnes marges de stabilite et un amortissement des mouvements phugoides et rapides de l'avion. Dans un premier temps, nous nous sommes principalement interesses aux methodes de synthese LTI et plus exactement a l'approche Hinfinity et la mu-synthese. Par la suite, nous avons accorde un interet particulier aux techniques de commande LPV. Pour mener a bien ce travail, nous avons envisage une approche frequentielle, typiquement Hinfinity. Cette approche est particulierement interessante, dans la mesure ou le modele de synthese est construit directement a partir des differentes specifications du cahier des charges. En effet, ces specifications sont traduites sous forme de gabarits frequentiels, correspondant a des ponderations en entree et en sortie que l'on retrouve dans la synthese Hinfinity classique. Par ailleurs, nous avons utilise une representation de type lineaire fractionnelle (LFT), jugee mieux adaptee pour la prise en compte des differents types d'incertitudes, qui peuvent intervenir sur le systeme. De plus, cette representation s'avere tres appropriee pour l'analyse de la robustesse via les outils de la mu-analyse. D'autre part, afin d'optimiser le compromis entre les specifications de robustesse et de performance, nous avons opte pour une structure de commande a 2 degres de liberte avec modele de reference. Enfin, ces techniques sont illustrees sur des applications realistes, demontrant ainsi la pertinence et l'applicabilite de chacune d'elle. Mots cles. Commande de vol, qualites de vol et manoeuvrabilite, commande robuste, approche Hinfinity , mu-synthese, systemes lineaires a parametres variants, sequencement de gains, transformation lineaire fractionnelle, inegalite matricielle lineaire.

Hentabli, Kamel

368

Mechanical behavior of low porosity carbonate rock: from brittle creep to ductile creep  

NASA Astrophysics Data System (ADS)

Mechanical compaction and associated porosity reduction play an important role in the diagenesis of porous rocks. They may also affect reservoir rocks during hydrocarbon production, as the pore pressure field is modified. This inelastic compaction can lead to subsidence, cause casing failure, trigger earthquake, or change the fluid transport properties. In addition, inelastic deformation can be time - dependent. In particular, brittle creep phenomena have been deeply investigated since the 90s, especially in sandstones. However knowledge of carbonates behavior is still insufficient. In this experimental study, we focus on the mechanical behavior of a low porosity (9%) white Tavel (France) carbonate rock (>98% calcite) at P-Q conditions beyond the elastic domain. It has been shown that in sandstones composed of quartz, cracks are developing under these conditions. However, in carbonates, calcite minerals can meanwhile also exhibit microplasticity. The samples were deformed in the triaxial cell of the Ecole Normale Superieure de Paris at effective confining pressures ranging from 35 MPa to 85 MPa and room temperature. Experiments were carried on dry and water saturated samples to explore the role played by the pore fluids. Time dependency was investigated by a creep steps methodology: at each step, differential stress was increased rapidly and kept constant for at least 24h. During these steps elastic wave velocities (P and S) and permeability were measured continuously. Our results show two different creep behaviors: (1) brittle creep is observed at low confining pressures, whereas (2) ductile creep is observed at higher confining pressures. These two creep behaviors have a different signature in term of elastic wave velocities and permeability changes. Indeed, in the brittle domain, the primary creep is associated with a decrease of elastic wave velocities and an increase of permeability, and no secondary creep is observed. In the ductile domain, the primary creep is also associated with a decreased in elastic wave velocity and an increase of the permeability. However, the secondary creep is associated with an increase of velocities and a decrease of permeability (pointing to recovery). This behavior observed in the ductile regime can be explained by two mechanisms: cracks propagation and plasticity. Indeed, the increase of stress induces fractures. When long term plastic phenomena take place at the tips of the cracks, these fractures close partially.

Nicolas, A.; Fortin, J.; Gueguen, Y.

2013-12-01

369

Synthese, caracterisation et applications de polyesters derives d'oligothiophenes  

NASA Astrophysics Data System (ADS)

Le travail presente ici a pour but de synthetiser des polyesters derives d'oligothiophenes utilisables dans des diodes electroluminescentes et des dispositifs optiques non-lineaires. Differents polyesters derives d'oligothiophenes (de une a six unites) ont ete synthetises par polycondensation en masse. Trois groupes espaceurs ont ete utilises: le 1, 10-decanediol, le 1,6-hexanediol et l'hexaethyleneglycol. La structure chimique des polyesters a ete etudiee entre autres, par spectroscopie RMN. Cette technique a montre que les polyesters avaient une structure parfaitement alternee. Les proprietes optiques de ces polyesters ont montre que cette famille de polyesters pouvait emettre sur une large gamme du spectre du visible, ce qui en fait de bons candidats pour les diodes electroluminescentes. En outre, a partir de quatre unites thiophene les polyesters ont montre une certaine electroactivite. Les polyesters avec cinq et six unites thiophene ont, de plus, la capacite d'etre reduits et les mesures de conductivite in-situ ont montre que les electrons et les trous sont transportes avec une efficacite comparable au sein du polymere. Enfin, les polyesters possedant un groupe espaceur hydrophile forment facilement des films par la technique de Langmuir-Blodgett. L'ensemble de ces proprietes a fait de ces polymeres de bons candidats pour la fabrication de diodes electroluminescentes a base de films Langmuir-Blodgett. Des resultats interessants ont ete obtenus avec les polyesters a base de derives du pentathiophene et du sexithiophene. Cependant, l'electroluminescence reste assez faible et une amelioration pourrait etre obtenue en utilisant des materiaux plus luminescents. Les proprietes non-lineaires de ces polyesters ont ete etudiees en solution par la technique du z-scan. Les valeurs de chi(3) extrapolees a un film mince sont tres superieures a celles obtenues avec des poly(3-alkylthiophenes) (10-9 esu vs 10 -12 esu, respectivement). Cette augmentation a ete attribuee au fait que la longueur de conjugaison est constante dans les polyesters et a l'etroitesse de la bande d'absorption. L'orientation des polyesters pourrait etre une voie prometteuse pour l'amelioration des proprietes non-lineaires.

Donat-Bouillud, Anne

370

Exhumation history of the Red River shear zone in northern Vietnam: New insights from zircon and apatite fission-track analysis  

NASA Astrophysics Data System (ADS)

A new set of zircon and apatite fission-track ages from the Ailao Shan and Day Nui Con Voi (DNCV) metamorphic massifs of the Red River shear zone (RRSZ) and neighboring rocks in northern Vietnam is presented. A complex, along-strike diachronous, denudation history is revealed. The southern sector of the DNCV cooled to about 100 °C by the Late Oligocene, whereas its central compartment was affected by the later thermotectonic evolution of the Song Chay dome to the E of the RRSZ, whose final exhumation occurred during the Early Miocene. The northern sector of the RRSZ is characterized by the 35 Ma Phan Si Pang pre- to synkinematic intrusion. Fission-track ages from a vertical section within the Phan Si Pang granite indicate rapid exhumation and cooling. The Paleozoic tectonic block to the west of the RRSZ (fission-track ages between 40 and 30 Ma) was exhumed and cooled earlier than the fault mylonite belt (fission track ages of 30 Ma and younger) and also than the eastern block. Its structural level is consistent with field observations that suggest the RRSZ in northern Vietnam to be a transtensional system, with a regional NE-SW oriented extension component.

Viola, G.; Anczkiewicz, R.

2008-06-01

371

Road map to a patient-centered research agenda at the intersection of hospital medicine and geriatric medicine.  

PubMed

As the United States ages, the patient population in acute care hospitals is increasingly older and more medically complex. Despite evidence of a high burden of disease, high costs, and often poor outcomes of care, there is limited understanding of the presentation, diagnostic strategies, and management of acute illness in older adults. In this paper, we present a strategy for the development of a research agenda at the intersection of hospital and geriatric medicine. This approach is informed by the Patient-Centered Outcomes Research Institute (PCORI) framework for identification and prioritization of research areas, emphasizing input from patients and caregivers. The framework's four components are: 1) Topic generation, 2) Gap Analysis in Systematic Review, 3) Value of information (VOI) analysis, and 4) Peer Review. An inclusive process for topic generation requiring the systematic engagement of multiple stakeholders, especially patients, is emphasized. In subsequent steps, researchers and stakeholders prioritize research topics in order to identify areas that optimize patient-centeredness, population impact, impact on clinical decision making, ease of implementation, and durability. Finally, next steps for dissemination of the research agenda and evaluation of the impact of the patient-centered research prioritization process are described. PMID:24557516

Wald, Heidi L; Leykum, Luci K; Mattison, Melissa L P; Vasilevskis, Eduard E; Meltzer, David O

2014-06-01

372

La prise en charge ? long terme de l'asthme chez les enfants inuits et des Premi?res nations : un outil de transfert du savoir fond? sur les lignes directrices canadiennes pour l'asthme p?diatrique, con?u pour ?tre utilis? par les professionnels de la sant? de premi?re ligne qui travaillent dans des communaut?s isol?es  

PubMed Central

L’asthme est un grave problème de santé pour les enfants inuits et des Premières nations. Chez les enfants de moins d’un an, il faut distinguer l’asthme de la bronchiolite virale, anormalement fréquente chez les enfants autochtones du Canada. Chez les enfants de moins de six ans, le diagnostic dépend de la présence de symptômes classiques, de l’absence de caractéristiques atypiques et de la consignation de la réponse au traitement, notamment la réponse rapide et transitoire aux bronchodilatateurs. Chez les enfants plus âgés, il faut, dans la mesure du possible, déterminer la présence d’une obstruction réversible des voies aériennes par spirométrie afin de confirmer le diagnostic, ainsi qu’évaluer et corriger les déclencheurs environnementaux. L’utilisation régulière de corticoïdes en aérosol est la principale mesure à prendre pour maintenir un bon contrôle de l’asthme chez les enfants asthmatiques. Les clients et leur famille devraient recevoir une formation sur l’asthme. Il faut réévaluer régulièrement le contrôle aux visites de suivi dans des centres de santé et rajuster le traitement à la dose la plus basse possible pour le maintien de ce contrôle.

Kovesi, Tom; Giles, Brenda Louise; Pasterkamp, Hans

373

PIRATE: pediatric imaging response assessment and targeting environment  

NASA Astrophysics Data System (ADS)

By combining the strengths of various imaging modalities, the multimodality imaging approach has potential to improve tumor staging, delineation of tumor boundaries, chemo-radiotherapy regime design, and treatment response assessment in cancer management. To address the urgent needs for efficient tools to analyze large-scale clinical trial data, we have developed an integrated multimodality, functional and anatomical imaging analysis software package for target definition and therapy response assessment in pediatric radiotherapy (RT) patients. Our software provides quantitative tools for automated image segmentation, region-of-interest (ROI) histogram analysis, spatial volume-of-interest (VOI) analysis, and voxel-wise correlation across modalities. To demonstrate the clinical applicability of this software, histogram analyses were performed on baseline and follow-up 18F-fluorodeoxyglucose (18F-FDG) PET images of nine patients with rhabdomyosarcoma enrolled in an institutional clinical trial at St. Jude Children's Research Hospital. In addition, we combined 18F-FDG PET, dynamic-contrast-enhanced (DCE) MR, and anatomical MR data to visualize the heterogeneity in tumor pathophysiology with the ultimate goal of adaptive targeting of regions with high tumor burden. Our software is able to simultaneously analyze multimodality images across multiple time points, which could greatly speed up the analysis of large-scale clinical trial data and validation of potential imaging biomarkers.

Glenn, Russell; Zhang, Yong; Krasin, Matthew; Hua, Chiaho

2010-03-01

374

Estimation of the breast skin-line in mammograms using multidirectional Gabor filters.  

PubMed

Segmentation of the breast region is a fundamental step in any system for computerized analysis of mammograms. In this work, we propose a novel procedure for the estimation of the breast skin-line based upon multidirectional Gabor filtering. The method includes an adaptive values-of-interest (VOI) transformation, extraction of the skin-air ribbon by Otsu's thresholding method and the Euclidean distance transform, Gabor filtering with 18 real kernels, and a step for suppression of false edge points using the magnitude and phase responses of the filters. On a test set of 361 images from different acquisition modalities (screen-film and full-field digital mammograms), the average Hausdorff and polyline distances obtained were 2.85 mm and 0.84 mm, respectively, with reference to the ground-truth boundaries provided by an expert radiologist. When compared with the results obtained by other state-of-the-art methods on the same set of images and with respect to the same ground-truth boundaries, our method mostly outperformed the other approaches. The results demonstrate the effectiveness and robustness of the proposed algorithm. PMID:24209932

Casti, P; Mencattini, A; Salmeri, M; Ancona, A; Mangeri, F; Pepe, M L; Rangayyan, R M

2013-11-01

375

Tracer kinetic model-driven registration for dynamic contrast-enhanced MRI time-series data.  

PubMed

Dynamic contrast-enhanced MRI (DCE-MRI) time series data are subject to unavoidable physiological motion during acquisition (e.g., due to breathing) and this motion causes significant errors when fitting tracer kinetic models to the data, particularly with voxel-by-voxel fitting approaches. Motion correction is problematic, as contrast enhancement introduces new features into postcontrast images and conventional registration similarity measures cannot fully account for the increased image information content. A methodology is presented for tracer kinetic model-driven registration that addresses these problems by explicitly including a model of contrast enhancement in the registration process. The iterative registration procedure is focused on a tumor volume of interest (VOI), employing a three-dimensional (3D) translational transformation that follows only tumor motion. The implementation accurately removes motion corruption in a DCE-MRI software phantom and it is able to reduce model fitting errors and improve localization in 3D parameter maps in patient data sets that were selected for significant motion problems. Sufficient improvement was observed in the modeling results to salvage clinical trial DCE-MRI data sets that would otherwise have to be rejected due to motion corruption. PMID:17969122

Buonaccorsi, Giovanni A; O'Connor, James P B; Caunce, Angela; Roberts, Caleb; Cheung, Sue; Watson, Yvonne; Davies, Karen; Hope, Lynn; Jackson, Alan; Jayson, Gordon C; Parker, Geoffrey J M

2007-11-01

376

Can Na18F PET/CT Be Used to Study Bone Remodeling in the Tibia When Patients Are Being Treated with a Taylor Spatial Frame?  

PubMed Central

Monitoring and quantifying bone remodeling are of interest, for example, in correction osteotomies, delayed fracture healing pseudarthrosis, bone lengthening, and other instances. Seven patients who had operations to attach an Ilizarov-derived Taylor Spatial Frame to the tibia gave informed consent. Each patient was examined by Na18F PET/CT twice, at approximately six weeks and three months after the operation. A validated software tool was used for the following processing steps. The first and second CT volumes were aligned in 3D and the respective PET volumes were aligned accordingly. In the first PET volume spherical volumes of interest (VOIs) were delineated for the crural fracture and normal bone and transferred to the second PET volume for SUVmax evaluation. This method potentially provides clinical insight into questions such as, when has the bone remodeling progressed well enough to safely remove the TSF? and when is intervention required, in a timelier manner than current methods? For example, in two patients who completed treatment, the SUVmax between the first and second PET/CT examination decreased by 42% and 13%, respectively. Further studies in a larger patient population are needed to verify these preliminary results by correlating regional Na18F PET measurements to clinical and radiological findings.

Lundblad, Henrik; Maguire, Gerald Q.; Olivecrona, Henrik; Jonsson, Cathrine; Jacobsson, Hans; Noz, Marilyn E.; Zeleznik, Michael P.; Weidenhielm, Lars; Sundin, Anders

2014-01-01

377

Matériaux pour la dépollution des gaz d'échappement automobile  

NASA Astrophysics Data System (ADS)

Les premières législations antipollution ont été mises en place suite à la détection, aux Etats Unis plus particulièrement en Californie, du smog photochimique et des pluies acides, néfastes pour la faune et la flore. Les estimations de la contribution de l'automobile aux émissions de composés, considérés comme précurseurs de ces phénomènes, ont été suffisantes pour provoquer la mise en place de normes draconiennes en matière d'émissions automobiles. Les matériaux catalytiques ont été évalués en tant que solution possible pour réduire les émissions à l'échappement. En Europe, l'utilisation des catalyseurs trois voies a été généralisée sur les véhicules essence fonctionnant à richesse stoechiométrique à partir de 1993. Une nouvelle génération de catalyseurs appelée piège à oxydes d'azote (NOx) est maintenant nécessaire pour le post-traitement des gaz d'échappement des motorisations à essence fonctionnant en mélange pauvre (combustion en présence d'un excès d'oxygène) pour diminuer la consommation et par conséquent réduire les émissions du CO2 connu pour son impact sur l'effet de serre. La dépollution des moteurs diesel via un catalyseur d'oxydation a été généralisée en Europe depuis 1996. La sévérisation des normes européennes impose pour les moteurs diesel le recours à des matériaux spécifiques pour le traitement des oxydes d'azotes et des particules par l'intermédiaire de filtres à particules dont l'efficacité de filtration est supérieure à 95%, mais doivent subir des régénérations périodiques.

Mouaddib-Moral, N.; Gauthier, C.

2002-04-01

378

Sensitivity and specificity of 3-D texture analysis of lung parenchyma is better than 2-D for discrimination of lung pathology in stage 0 COPD  

NASA Astrophysics Data System (ADS)

Lung parenchyma evaluation via multidetector-row CT (MDCT), has significantly altered clinical practice in the early detection of lung disease. Our goal is to enhance our texture-based tissue classification ability to differentiate early pathologic processes by extending our 2-D Adaptive Multiple Feature Method (AMFM) to 3-D AMFM. We performed MDCT on 34 human volunteers in five categories: emphysema in severe Chronic Obstructive Pulmonary Disease (COPD) as EC, emphysema in mild COPD (MC), normal appearing lung in COPD (NC), non-smokers with normal lung function (NN), smokers with normal function (NS). We volumetrically excluded the airway and vessel regions, calculated 24 volumetric texture features for each Volume of Interest (VOI); and used Bayesian rules for discrimination. Leave-one-out and half-half methods were used for testing. Sensitivity, specificity and accuracy were calculated. The accuracy of the leave-one-out method for the four-class classification in the form of 3-D/2-D is: EC: 84.9%/70.7%, MC: 89.8%/82.7%; NC: 87.5.0%/49.6%; NN: 100.0%/60.0%. The accuracy of the leave-one-out method for the two-class classification in the form of 3-D/2-D is: NN: 99.3%/71.6%; NS: 99.7%/74.5%. We conclude that 3-D AMFM analysis of the lung parenchyma improves discrimination compared to 2-D analysis of the same images.

Xu, Ye; Sonka, Milan; McLennan, Geoffrey; Guo, Junfeng; Hoffman, Eric

2005-04-01

379

Shimming with permanent magnets for the x-ray detector in a hybrid x-ray/MR system  

SciTech Connect

In this x-ray/MR hybrid system an x-ray flat panel detector is placed under the patient cradle, close to the MR volume of interest (VOI), where the magnetic field strength is {approx}0.5 T. Immersed in this strong field, several electronic components inside the detector become magnetized and create an additional magnetic field that is superimposed on the original field of the MR scanner. Even after linear shimming, the field homogeneity of the MR scanner remains disrupted by the detector. The authors characterize the field due to the detector with the field of two magnetic dipoles and further show that two sets of permanent magnets (NdFeB) can withstand the main magnetic field and compensate for the nonlinear components of the additional field. The ideal number of magnets and their locations are calculated based on a field map measured with the detector in place. Experimental results demonstrate great promise for this technique, which may be useful in many settings where devices with magnetic components need to be placed inside or close to an MR scanner.

Wen Zhifei; Fahrig, Rebecca; Williams, Scott T.; Pelc, Norbert J. [Departments of Radiology and Physics, Stanford University, Stanford, California 94305 (United States); Department of Radiology, Stanford University, Stanford, California 94305 (United States); Departments of Radiology and Bioengineering, Stanford University, Stanford, California 94305 (United States)

2008-09-15

380

High-Resolution 3D Arteriography of Chronic Total Peripheral Occlusions Using a T1-W Turbo Spin-Echo Sequence With Inner-Volume Imaging  

PubMed Central

Percutaneous revascularization of peripheral artery chronic total occlusion (CTO) is challenging under X-ray guidance without direct image feedback, due to poor visualization of the obstructed segment and underappreciation of vessel tortuosity. Operators are required to steer interventional devices relatively “blindly,” and therefore procedural failure or perforation may occur. Alternatively, MRI may allow complete visualization of both patent and occluded arterial segments. We designed and implemented a 3D high-resolution, T1-weighted (T1-W) turbo spin-echo (TSE) MRI sequence with inner-volume (IV) imaging to enable detailed peripheral artery CTO imaging. Using this sequence, high-resolution volumes of interest (VOIs) around the vessel were achieved within 5-10 min. This imaging approach may be used for rapid pre- and postprocedural evaluations, and as a 3D roadmap that can be overlaid during real-time X-, MR-, or XMR-guided catheterization. Experiments were successfully performed on a carotid CTO model in swine ex vivo, and in peripheral arteries in normal volunteers and patients in vivo. Delineation of the vascular architecture, including contrast differences between the patent and occluded artery segments, and lesion morphology heterogeneity were visualized.

Sampath, Smita; Raval, Amish N.; Lederman, Robert J.; McVeigh, Elliot R.

2007-01-01

381

Coupling hydrodynamic models and value of information for designing stage monitoring networks  

NASA Astrophysics Data System (ADS)

Because the collection of data in water systems is important for making informed decisions, monitoring networks are designed and installed in such systems. Traditionally, the design of hydrometric monitoring networks has been concentrated on measuring streamflow/precipitation at particular key (gauged) sites so that streamflow/precipitation can be estimated accurately at ungauged sites. Although many methods take into account a set of final users of the information, there appears to be no method that explicitly considers them in the mathematical formulation of the decision-making process. This paper presents a novel approach for designing monitoring networks in a water system using the concept of value of information (VOI). This concept takes into account three main factors: (1) the belief that the decision maker has about the state of the water system before having any information; (2) the consequences associated with the decision of having to choose among several possible management actions given the state of the water system; and (3) the evaluation and update of new information when it becomes available. The methodology uses a water level time series generated by a hydrodynamic model at every computational point, each one being a potential monitor site. The method is tested in a polder system in the Netherlands, where monitoring is required to make informed decisions about the operation of a set of hydraulic structures to reduce flood impacts.

Alfonso, Leonardo; Price, Roland

2012-08-01

382

Ressources en ligne en p?diatrie  

PubMed Central

RÉSUMÉ Question Depuis les dernières années, les parents d’enfants que je vois en clinique font souvent des recherches en ligne concernant des questions médicales. Dans quelle mesure les ressources en ligne sontelles fiables dans le domaine de la pédiatrie et quels conseils puis-je donner aux parents qui s’informent en ligne concernant la santé de leurs enfants? Réponse Le recours à Internet pour trouver des renseignements médicaux a connu une hausse dramatique au cours de la dernière décennie, y compris dans le domaine de la pédiatrie. Les quantités énormes d’information sont sources de confusion autant pour les parents que pour les professionnels de la santé et les moteurs généraux de recherche n’ont pas ce qu’il faut pour permettre de discerner les renseignements fiables de ceux qui sont biaisés. Les médecins peuvent élaborer des sites web présentant des renseignements fiables, conseiller les parents sur les façons de cerner les sources d’information dignes de confiance et donner des exemples de sites web à consulter sur des sujets reliés à la santé des enfants.

Goldman, Ran D.

2014-01-01

383

Magellan Prelaunch Mission Operations Report  

NASA Technical Reports Server (NTRS)

The Magellan spacecraft will be launched from Kennedy Space Center (KSC) within a 31-day overall launch period extending from April 28 to May 28, 1989. The launch will use the Shuttle Orbiter Atlantis to lift an Inertial Upper Stage (IUS) and the Magellan Spacecraft into low Earth orbit. After the Shuttle achieves its parking orbit, the IUS and attached Magellan spacecraft are deployed from the payload bay. After a short coast time, the two-stage IUS is fired to inject the Magellan spacecraft into an Earth-Venus transfer trajectory. The Magellan spacecraft is powered by single degree of freedom, sun-tracking, solar panels charging a set of nickel-cadmium batteries. The spacecraft is three-axis stabilized by reaction wheels using gyros and a star sensor for attitude reference. The spacecraft carries a solid rocket motor for Venus Orbit Insertion (VOI). A hydrazine propulsion system allows trajectory correction and prevents saturation of the reaction wheels. Communication with Earth through the Deep Space Network (DSN) is provided by S- and X-band telemetry channels, through alternatively a low, medium, or 3.7 m high-gain parabolic antenna rigidly attached to the spacecraft. The high-gain antenna also serves as the radar and radiometer antenna during orbit around Venus.

1989-01-01

384

Quantitative Accuracy of Low-Count SPECT Imaging in Phantom and In Vivo Mouse Studies  

PubMed Central

We investigated the accuracy of a single photon emission computed tomography (SPECT) system in quantifying a wide range of radioactivity concentrations using different scan times in both phantom and animal models. A phantom containing various amounts of In-111 or Tc-99m was imaged until the activity had decayed close to background levels. Scans were acquired for different durations, employing different collimator pinhole sizes. VOI analysis was performed to quantify uptake in the images and the values compared to the true activity. The phantom results were then validated in tumour-bearing mice. The use of an appropriate calibration phantom and disabling of a background subtraction feature meant that absolute errors were within 12% of the true activity. Furthermore, a comparison of in vivo imaging and biodistribution studies in mice showed a correlation of 0.99 for activities over the 200?kBq to 5?MBq range. We conclude that the quantitative information provided by the NanoSPECT camera is accurate and allows replacement of dissection studies for assessment of radiotracer biodistribution in mouse models.